| /* |
| * Block driver for the QCOW version 2 format |
| * |
| * Copyright (c) 2004-2006 Fabrice Bellard |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to deal |
| * in the Software without restriction, including without limitation the rights |
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| * copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| * THE SOFTWARE. |
| */ |
| |
| #include "qemu/osdep.h" |
| |
| #include "block/qdict.h" |
| #include "sysemu/block-backend.h" |
| #include "qemu/main-loop.h" |
| #include "qemu/module.h" |
| #include "qcow2.h" |
| #include "qemu/error-report.h" |
| #include "qapi/error.h" |
| #include "qapi/qapi-events-block-core.h" |
| #include "qapi/qmp/qdict.h" |
| #include "qapi/qmp/qstring.h" |
| #include "trace.h" |
| #include "qemu/option_int.h" |
| #include "qemu/cutils.h" |
| #include "qemu/bswap.h" |
| #include "qapi/qobject-input-visitor.h" |
| #include "qapi/qapi-visit-block-core.h" |
| #include "crypto.h" |
| #include "block/aio_task.h" |
| |
| /* |
| Differences with QCOW: |
| |
| - Support for multiple incremental snapshots. |
| - Memory management by reference counts. |
| - Clusters which have a reference count of one have the bit |
| QCOW_OFLAG_COPIED to optimize write performance. |
| - Size of compressed clusters is stored in sectors to reduce bit usage |
| in the cluster offsets. |
| - Support for storing additional data (such as the VM state) in the |
| snapshots. |
| - If a backing store is used, the cluster size is not constrained |
| (could be backported to QCOW). |
| - L2 tables have always a size of one cluster. |
| */ |
| |
| |
| typedef struct { |
| uint32_t magic; |
| uint32_t len; |
| } QEMU_PACKED QCowExtension; |
| |
| #define QCOW2_EXT_MAGIC_END 0 |
| #define QCOW2_EXT_MAGIC_BACKING_FORMAT 0xe2792aca |
| #define QCOW2_EXT_MAGIC_FEATURE_TABLE 0x6803f857 |
| #define QCOW2_EXT_MAGIC_CRYPTO_HEADER 0x0537be77 |
| #define QCOW2_EXT_MAGIC_BITMAPS 0x23852875 |
| #define QCOW2_EXT_MAGIC_DATA_FILE 0x44415441 |
| |
| static int coroutine_fn |
| qcow2_co_preadv_compressed(BlockDriverState *bs, |
| uint64_t cluster_descriptor, |
| uint64_t offset, |
| uint64_t bytes, |
| QEMUIOVector *qiov, |
| size_t qiov_offset); |
| |
| static int qcow2_probe(const uint8_t *buf, int buf_size, const char *filename) |
| { |
| const QCowHeader *cow_header = (const void *)buf; |
| |
| if (buf_size >= sizeof(QCowHeader) && |
| be32_to_cpu(cow_header->magic) == QCOW_MAGIC && |
| be32_to_cpu(cow_header->version) >= 2) |
| return 100; |
| else |
| return 0; |
| } |
| |
| |
| static ssize_t qcow2_crypto_hdr_read_func(QCryptoBlock *block, size_t offset, |
| uint8_t *buf, size_t buflen, |
| void *opaque, Error **errp) |
| { |
| BlockDriverState *bs = opaque; |
| BDRVQcow2State *s = bs->opaque; |
| ssize_t ret; |
| |
| if ((offset + buflen) > s->crypto_header.length) { |
| error_setg(errp, "Request for data outside of extension header"); |
| return -1; |
| } |
| |
| ret = bdrv_pread(bs->file, |
| s->crypto_header.offset + offset, buf, buflen); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not read encryption header"); |
| return -1; |
| } |
| return ret; |
| } |
| |
| |
| static ssize_t qcow2_crypto_hdr_init_func(QCryptoBlock *block, size_t headerlen, |
| void *opaque, Error **errp) |
| { |
| BlockDriverState *bs = opaque; |
| BDRVQcow2State *s = bs->opaque; |
| int64_t ret; |
| int64_t clusterlen; |
| |
| ret = qcow2_alloc_clusters(bs, headerlen); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, |
| "Cannot allocate cluster for LUKS header size %zu", |
| headerlen); |
| return -1; |
| } |
| |
| s->crypto_header.length = headerlen; |
| s->crypto_header.offset = ret; |
| |
| /* |
| * Zero fill all space in cluster so it has predictable |
| * content, as we may not initialize some regions of the |
| * header (eg only 1 out of 8 key slots will be initialized) |
| */ |
| clusterlen = size_to_clusters(s, headerlen) * s->cluster_size; |
| assert(qcow2_pre_write_overlap_check(bs, 0, ret, clusterlen, false) == 0); |
| ret = bdrv_pwrite_zeroes(bs->file, |
| ret, |
| clusterlen, 0); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not zero fill encryption header"); |
| return -1; |
| } |
| |
| return ret; |
| } |
| |
| |
| static ssize_t qcow2_crypto_hdr_write_func(QCryptoBlock *block, size_t offset, |
| const uint8_t *buf, size_t buflen, |
| void *opaque, Error **errp) |
| { |
| BlockDriverState *bs = opaque; |
| BDRVQcow2State *s = bs->opaque; |
| ssize_t ret; |
| |
| if ((offset + buflen) > s->crypto_header.length) { |
| error_setg(errp, "Request for data outside of extension header"); |
| return -1; |
| } |
| |
| ret = bdrv_pwrite(bs->file, |
| s->crypto_header.offset + offset, buf, buflen); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not read encryption header"); |
| return -1; |
| } |
| return ret; |
| } |
| |
| static QDict* |
| qcow2_extract_crypto_opts(QemuOpts *opts, const char *fmt, Error **errp) |
| { |
| QDict *cryptoopts_qdict; |
| QDict *opts_qdict; |
| |
| /* Extract "encrypt." options into a qdict */ |
| opts_qdict = qemu_opts_to_qdict(opts, NULL); |
| qdict_extract_subqdict(opts_qdict, &cryptoopts_qdict, "encrypt."); |
| qobject_unref(opts_qdict); |
| qdict_put_str(cryptoopts_qdict, "format", fmt); |
| return cryptoopts_qdict; |
| } |
| |
| /* |
| * read qcow2 extension and fill bs |
| * start reading from start_offset |
| * finish reading upon magic of value 0 or when end_offset reached |
| * unknown magic is skipped (future extension this version knows nothing about) |
| * return 0 upon success, non-0 otherwise |
| */ |
| static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset, |
| uint64_t end_offset, void **p_feature_table, |
| int flags, bool *need_update_header, |
| Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| QCowExtension ext; |
| uint64_t offset; |
| int ret; |
| Qcow2BitmapHeaderExt bitmaps_ext; |
| |
| if (need_update_header != NULL) { |
| *need_update_header = false; |
| } |
| |
| #ifdef DEBUG_EXT |
| printf("qcow2_read_extensions: start=%ld end=%ld\n", start_offset, end_offset); |
| #endif |
| offset = start_offset; |
| while (offset < end_offset) { |
| |
| #ifdef DEBUG_EXT |
| /* Sanity check */ |
| if (offset > s->cluster_size) |
| printf("qcow2_read_extension: suspicious offset %lu\n", offset); |
| |
| printf("attempting to read extended header in offset %lu\n", offset); |
| #endif |
| |
| ret = bdrv_pread(bs->file, offset, &ext, sizeof(ext)); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "qcow2_read_extension: ERROR: " |
| "pread fail from offset %" PRIu64, offset); |
| return 1; |
| } |
| ext.magic = be32_to_cpu(ext.magic); |
| ext.len = be32_to_cpu(ext.len); |
| offset += sizeof(ext); |
| #ifdef DEBUG_EXT |
| printf("ext.magic = 0x%x\n", ext.magic); |
| #endif |
| if (offset > end_offset || ext.len > end_offset - offset) { |
| error_setg(errp, "Header extension too large"); |
| return -EINVAL; |
| } |
| |
| switch (ext.magic) { |
| case QCOW2_EXT_MAGIC_END: |
| return 0; |
| |
| case QCOW2_EXT_MAGIC_BACKING_FORMAT: |
| if (ext.len >= sizeof(bs->backing_format)) { |
| error_setg(errp, "ERROR: ext_backing_format: len=%" PRIu32 |
| " too large (>=%zu)", ext.len, |
| sizeof(bs->backing_format)); |
| return 2; |
| } |
| ret = bdrv_pread(bs->file, offset, bs->backing_format, ext.len); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "ERROR: ext_backing_format: " |
| "Could not read format name"); |
| return 3; |
| } |
| bs->backing_format[ext.len] = '\0'; |
| s->image_backing_format = g_strdup(bs->backing_format); |
| #ifdef DEBUG_EXT |
| printf("Qcow2: Got format extension %s\n", bs->backing_format); |
| #endif |
| break; |
| |
| case QCOW2_EXT_MAGIC_FEATURE_TABLE: |
| if (p_feature_table != NULL) { |
| void *feature_table = g_malloc0(ext.len + 2 * sizeof(Qcow2Feature)); |
| ret = bdrv_pread(bs->file, offset , feature_table, ext.len); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "ERROR: ext_feature_table: " |
| "Could not read table"); |
| return ret; |
| } |
| |
| *p_feature_table = feature_table; |
| } |
| break; |
| |
| case QCOW2_EXT_MAGIC_CRYPTO_HEADER: { |
| unsigned int cflags = 0; |
| if (s->crypt_method_header != QCOW_CRYPT_LUKS) { |
| error_setg(errp, "CRYPTO header extension only " |
| "expected with LUKS encryption method"); |
| return -EINVAL; |
| } |
| if (ext.len != sizeof(Qcow2CryptoHeaderExtension)) { |
| error_setg(errp, "CRYPTO header extension size %u, " |
| "but expected size %zu", ext.len, |
| sizeof(Qcow2CryptoHeaderExtension)); |
| return -EINVAL; |
| } |
| |
| ret = bdrv_pread(bs->file, offset, &s->crypto_header, ext.len); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, |
| "Unable to read CRYPTO header extension"); |
| return ret; |
| } |
| s->crypto_header.offset = be64_to_cpu(s->crypto_header.offset); |
| s->crypto_header.length = be64_to_cpu(s->crypto_header.length); |
| |
| if ((s->crypto_header.offset % s->cluster_size) != 0) { |
| error_setg(errp, "Encryption header offset '%" PRIu64 "' is " |
| "not a multiple of cluster size '%u'", |
| s->crypto_header.offset, s->cluster_size); |
| return -EINVAL; |
| } |
| |
| if (flags & BDRV_O_NO_IO) { |
| cflags |= QCRYPTO_BLOCK_OPEN_NO_IO; |
| } |
| s->crypto = qcrypto_block_open(s->crypto_opts, "encrypt.", |
| qcow2_crypto_hdr_read_func, |
| bs, cflags, QCOW2_MAX_THREADS, errp); |
| if (!s->crypto) { |
| return -EINVAL; |
| } |
| } break; |
| |
| case QCOW2_EXT_MAGIC_BITMAPS: |
| if (ext.len != sizeof(bitmaps_ext)) { |
| error_setg_errno(errp, -ret, "bitmaps_ext: " |
| "Invalid extension length"); |
| return -EINVAL; |
| } |
| |
| if (!(s->autoclear_features & QCOW2_AUTOCLEAR_BITMAPS)) { |
| if (s->qcow_version < 3) { |
| /* Let's be a bit more specific */ |
| warn_report("This qcow2 v2 image contains bitmaps, but " |
| "they may have been modified by a program " |
| "without persistent bitmap support; so now " |
| "they must all be considered inconsistent"); |
| } else { |
| warn_report("a program lacking bitmap support " |
| "modified this file, so all bitmaps are now " |
| "considered inconsistent"); |
| } |
| error_printf("Some clusters may be leaked, " |
| "run 'qemu-img check -r' on the image " |
| "file to fix."); |
| if (need_update_header != NULL) { |
| /* Updating is needed to drop invalid bitmap extension. */ |
| *need_update_header = true; |
| } |
| break; |
| } |
| |
| ret = bdrv_pread(bs->file, offset, &bitmaps_ext, ext.len); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "bitmaps_ext: " |
| "Could not read ext header"); |
| return ret; |
| } |
| |
| if (bitmaps_ext.reserved32 != 0) { |
| error_setg_errno(errp, -ret, "bitmaps_ext: " |
| "Reserved field is not zero"); |
| return -EINVAL; |
| } |
| |
| bitmaps_ext.nb_bitmaps = be32_to_cpu(bitmaps_ext.nb_bitmaps); |
| bitmaps_ext.bitmap_directory_size = |
| be64_to_cpu(bitmaps_ext.bitmap_directory_size); |
| bitmaps_ext.bitmap_directory_offset = |
| be64_to_cpu(bitmaps_ext.bitmap_directory_offset); |
| |
| if (bitmaps_ext.nb_bitmaps > QCOW2_MAX_BITMAPS) { |
| error_setg(errp, |
| "bitmaps_ext: Image has %" PRIu32 " bitmaps, " |
| "exceeding the QEMU supported maximum of %d", |
| bitmaps_ext.nb_bitmaps, QCOW2_MAX_BITMAPS); |
| return -EINVAL; |
| } |
| |
| if (bitmaps_ext.nb_bitmaps == 0) { |
| error_setg(errp, "found bitmaps extension with zero bitmaps"); |
| return -EINVAL; |
| } |
| |
| if (offset_into_cluster(s, bitmaps_ext.bitmap_directory_offset)) { |
| error_setg(errp, "bitmaps_ext: " |
| "invalid bitmap directory offset"); |
| return -EINVAL; |
| } |
| |
| if (bitmaps_ext.bitmap_directory_size > |
| QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { |
| error_setg(errp, "bitmaps_ext: " |
| "bitmap directory size (%" PRIu64 ") exceeds " |
| "the maximum supported size (%d)", |
| bitmaps_ext.bitmap_directory_size, |
| QCOW2_MAX_BITMAP_DIRECTORY_SIZE); |
| return -EINVAL; |
| } |
| |
| s->nb_bitmaps = bitmaps_ext.nb_bitmaps; |
| s->bitmap_directory_offset = |
| bitmaps_ext.bitmap_directory_offset; |
| s->bitmap_directory_size = |
| bitmaps_ext.bitmap_directory_size; |
| |
| #ifdef DEBUG_EXT |
| printf("Qcow2: Got bitmaps extension: " |
| "offset=%" PRIu64 " nb_bitmaps=%" PRIu32 "\n", |
| s->bitmap_directory_offset, s->nb_bitmaps); |
| #endif |
| break; |
| |
| case QCOW2_EXT_MAGIC_DATA_FILE: |
| { |
| s->image_data_file = g_malloc0(ext.len + 1); |
| ret = bdrv_pread(bs->file, offset, s->image_data_file, ext.len); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, |
| "ERROR: Could not read data file name"); |
| return ret; |
| } |
| #ifdef DEBUG_EXT |
| printf("Qcow2: Got external data file %s\n", s->image_data_file); |
| #endif |
| break; |
| } |
| |
| default: |
| /* unknown magic - save it in case we need to rewrite the header */ |
| /* If you add a new feature, make sure to also update the fast |
| * path of qcow2_make_empty() to deal with it. */ |
| { |
| Qcow2UnknownHeaderExtension *uext; |
| |
| uext = g_malloc0(sizeof(*uext) + ext.len); |
| uext->magic = ext.magic; |
| uext->len = ext.len; |
| QLIST_INSERT_HEAD(&s->unknown_header_ext, uext, next); |
| |
| ret = bdrv_pread(bs->file, offset , uext->data, uext->len); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "ERROR: unknown extension: " |
| "Could not read data"); |
| return ret; |
| } |
| } |
| break; |
| } |
| |
| offset += ((ext.len + 7) & ~7); |
| } |
| |
| return 0; |
| } |
| |
| static void cleanup_unknown_header_ext(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| Qcow2UnknownHeaderExtension *uext, *next; |
| |
| QLIST_FOREACH_SAFE(uext, &s->unknown_header_ext, next, next) { |
| QLIST_REMOVE(uext, next); |
| g_free(uext); |
| } |
| } |
| |
| static void report_unsupported_feature(Error **errp, Qcow2Feature *table, |
| uint64_t mask) |
| { |
| g_autoptr(GString) features = g_string_sized_new(60); |
| |
| while (table && table->name[0] != '\0') { |
| if (table->type == QCOW2_FEAT_TYPE_INCOMPATIBLE) { |
| if (mask & (1ULL << table->bit)) { |
| if (features->len > 0) { |
| g_string_append(features, ", "); |
| } |
| g_string_append_printf(features, "%.46s", table->name); |
| mask &= ~(1ULL << table->bit); |
| } |
| } |
| table++; |
| } |
| |
| if (mask) { |
| if (features->len > 0) { |
| g_string_append(features, ", "); |
| } |
| g_string_append_printf(features, |
| "Unknown incompatible feature: %" PRIx64, mask); |
| } |
| |
| error_setg(errp, "Unsupported qcow2 feature(s): %s", features->str); |
| } |
| |
| /* |
| * Sets the dirty bit and flushes afterwards if necessary. |
| * |
| * The incompatible_features bit is only set if the image file header was |
| * updated successfully. Therefore it is not required to check the return |
| * value of this function. |
| */ |
| int qcow2_mark_dirty(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| uint64_t val; |
| int ret; |
| |
| assert(s->qcow_version >= 3); |
| |
| if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) { |
| return 0; /* already dirty */ |
| } |
| |
| val = cpu_to_be64(s->incompatible_features | QCOW2_INCOMPAT_DIRTY); |
| ret = bdrv_pwrite(bs->file, offsetof(QCowHeader, incompatible_features), |
| &val, sizeof(val)); |
| if (ret < 0) { |
| return ret; |
| } |
| ret = bdrv_flush(bs->file->bs); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| /* Only treat image as dirty if the header was updated successfully */ |
| s->incompatible_features |= QCOW2_INCOMPAT_DIRTY; |
| return 0; |
| } |
| |
| /* |
| * Clears the dirty bit and flushes before if necessary. Only call this |
| * function when there are no pending requests, it does not guard against |
| * concurrent requests dirtying the image. |
| */ |
| static int qcow2_mark_clean(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| |
| if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) { |
| int ret; |
| |
| s->incompatible_features &= ~QCOW2_INCOMPAT_DIRTY; |
| |
| ret = qcow2_flush_caches(bs); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| return qcow2_update_header(bs); |
| } |
| return 0; |
| } |
| |
| /* |
| * Marks the image as corrupt. |
| */ |
| int qcow2_mark_corrupt(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| |
| s->incompatible_features |= QCOW2_INCOMPAT_CORRUPT; |
| return qcow2_update_header(bs); |
| } |
| |
| /* |
| * Marks the image as consistent, i.e., unsets the corrupt bit, and flushes |
| * before if necessary. |
| */ |
| int qcow2_mark_consistent(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| |
| if (s->incompatible_features & QCOW2_INCOMPAT_CORRUPT) { |
| int ret = qcow2_flush_caches(bs); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| s->incompatible_features &= ~QCOW2_INCOMPAT_CORRUPT; |
| return qcow2_update_header(bs); |
| } |
| return 0; |
| } |
| |
| static void qcow2_add_check_result(BdrvCheckResult *out, |
| const BdrvCheckResult *src, |
| bool set_allocation_info) |
| { |
| out->corruptions += src->corruptions; |
| out->leaks += src->leaks; |
| out->check_errors += src->check_errors; |
| out->corruptions_fixed += src->corruptions_fixed; |
| out->leaks_fixed += src->leaks_fixed; |
| |
| if (set_allocation_info) { |
| out->image_end_offset = src->image_end_offset; |
| out->bfi = src->bfi; |
| } |
| } |
| |
| static int coroutine_fn qcow2_co_check_locked(BlockDriverState *bs, |
| BdrvCheckResult *result, |
| BdrvCheckMode fix) |
| { |
| BdrvCheckResult snapshot_res = {}; |
| BdrvCheckResult refcount_res = {}; |
| int ret; |
| |
| memset(result, 0, sizeof(*result)); |
| |
| ret = qcow2_check_read_snapshot_table(bs, &snapshot_res, fix); |
| if (ret < 0) { |
| qcow2_add_check_result(result, &snapshot_res, false); |
| return ret; |
| } |
| |
| ret = qcow2_check_refcounts(bs, &refcount_res, fix); |
| qcow2_add_check_result(result, &refcount_res, true); |
| if (ret < 0) { |
| qcow2_add_check_result(result, &snapshot_res, false); |
| return ret; |
| } |
| |
| ret = qcow2_check_fix_snapshot_table(bs, &snapshot_res, fix); |
| qcow2_add_check_result(result, &snapshot_res, false); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| if (fix && result->check_errors == 0 && result->corruptions == 0) { |
| ret = qcow2_mark_clean(bs); |
| if (ret < 0) { |
| return ret; |
| } |
| return qcow2_mark_consistent(bs); |
| } |
| return ret; |
| } |
| |
| static int coroutine_fn qcow2_co_check(BlockDriverState *bs, |
| BdrvCheckResult *result, |
| BdrvCheckMode fix) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int ret; |
| |
| qemu_co_mutex_lock(&s->lock); |
| ret = qcow2_co_check_locked(bs, result, fix); |
| qemu_co_mutex_unlock(&s->lock); |
| return ret; |
| } |
| |
| int qcow2_validate_table(BlockDriverState *bs, uint64_t offset, |
| uint64_t entries, size_t entry_len, |
| int64_t max_size_bytes, const char *table_name, |
| Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| |
| if (entries > max_size_bytes / entry_len) { |
| error_setg(errp, "%s too large", table_name); |
| return -EFBIG; |
| } |
| |
| /* Use signed INT64_MAX as the maximum even for uint64_t header fields, |
| * because values will be passed to qemu functions taking int64_t. */ |
| if ((INT64_MAX - entries * entry_len < offset) || |
| (offset_into_cluster(s, offset) != 0)) { |
| error_setg(errp, "%s offset invalid", table_name); |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static const char *const mutable_opts[] = { |
| QCOW2_OPT_LAZY_REFCOUNTS, |
| QCOW2_OPT_DISCARD_REQUEST, |
| QCOW2_OPT_DISCARD_SNAPSHOT, |
| QCOW2_OPT_DISCARD_OTHER, |
| QCOW2_OPT_OVERLAP, |
| QCOW2_OPT_OVERLAP_TEMPLATE, |
| QCOW2_OPT_OVERLAP_MAIN_HEADER, |
| QCOW2_OPT_OVERLAP_ACTIVE_L1, |
| QCOW2_OPT_OVERLAP_ACTIVE_L2, |
| QCOW2_OPT_OVERLAP_REFCOUNT_TABLE, |
| QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK, |
| QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE, |
| QCOW2_OPT_OVERLAP_INACTIVE_L1, |
| QCOW2_OPT_OVERLAP_INACTIVE_L2, |
| QCOW2_OPT_OVERLAP_BITMAP_DIRECTORY, |
| QCOW2_OPT_CACHE_SIZE, |
| QCOW2_OPT_L2_CACHE_SIZE, |
| QCOW2_OPT_L2_CACHE_ENTRY_SIZE, |
| QCOW2_OPT_REFCOUNT_CACHE_SIZE, |
| QCOW2_OPT_CACHE_CLEAN_INTERVAL, |
| NULL |
| }; |
| |
| static QemuOptsList qcow2_runtime_opts = { |
| .name = "qcow2", |
| .head = QTAILQ_HEAD_INITIALIZER(qcow2_runtime_opts.head), |
| .desc = { |
| { |
| .name = QCOW2_OPT_LAZY_REFCOUNTS, |
| .type = QEMU_OPT_BOOL, |
| .help = "Postpone refcount updates", |
| }, |
| { |
| .name = QCOW2_OPT_DISCARD_REQUEST, |
| .type = QEMU_OPT_BOOL, |
| .help = "Pass guest discard requests to the layer below", |
| }, |
| { |
| .name = QCOW2_OPT_DISCARD_SNAPSHOT, |
| .type = QEMU_OPT_BOOL, |
| .help = "Generate discard requests when snapshot related space " |
| "is freed", |
| }, |
| { |
| .name = QCOW2_OPT_DISCARD_OTHER, |
| .type = QEMU_OPT_BOOL, |
| .help = "Generate discard requests when other clusters are freed", |
| }, |
| { |
| .name = QCOW2_OPT_OVERLAP, |
| .type = QEMU_OPT_STRING, |
| .help = "Selects which overlap checks to perform from a range of " |
| "templates (none, constant, cached, all)", |
| }, |
| { |
| .name = QCOW2_OPT_OVERLAP_TEMPLATE, |
| .type = QEMU_OPT_STRING, |
| .help = "Selects which overlap checks to perform from a range of " |
| "templates (none, constant, cached, all)", |
| }, |
| { |
| .name = QCOW2_OPT_OVERLAP_MAIN_HEADER, |
| .type = QEMU_OPT_BOOL, |
| .help = "Check for unintended writes into the main qcow2 header", |
| }, |
| { |
| .name = QCOW2_OPT_OVERLAP_ACTIVE_L1, |
| .type = QEMU_OPT_BOOL, |
| .help = "Check for unintended writes into the active L1 table", |
| }, |
| { |
| .name = QCOW2_OPT_OVERLAP_ACTIVE_L2, |
| .type = QEMU_OPT_BOOL, |
| .help = "Check for unintended writes into an active L2 table", |
| }, |
| { |
| .name = QCOW2_OPT_OVERLAP_REFCOUNT_TABLE, |
| .type = QEMU_OPT_BOOL, |
| .help = "Check for unintended writes into the refcount table", |
| }, |
| { |
| .name = QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK, |
| .type = QEMU_OPT_BOOL, |
| .help = "Check for unintended writes into a refcount block", |
| }, |
| { |
| .name = QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE, |
| .type = QEMU_OPT_BOOL, |
| .help = "Check for unintended writes into the snapshot table", |
| }, |
| { |
| .name = QCOW2_OPT_OVERLAP_INACTIVE_L1, |
| .type = QEMU_OPT_BOOL, |
| .help = "Check for unintended writes into an inactive L1 table", |
| }, |
| { |
| .name = QCOW2_OPT_OVERLAP_INACTIVE_L2, |
| .type = QEMU_OPT_BOOL, |
| .help = "Check for unintended writes into an inactive L2 table", |
| }, |
| { |
| .name = QCOW2_OPT_OVERLAP_BITMAP_DIRECTORY, |
| .type = QEMU_OPT_BOOL, |
| .help = "Check for unintended writes into the bitmap directory", |
| }, |
| { |
| .name = QCOW2_OPT_CACHE_SIZE, |
| .type = QEMU_OPT_SIZE, |
| .help = "Maximum combined metadata (L2 tables and refcount blocks) " |
| "cache size", |
| }, |
| { |
| .name = QCOW2_OPT_L2_CACHE_SIZE, |
| .type = QEMU_OPT_SIZE, |
| .help = "Maximum L2 table cache size", |
| }, |
| { |
| .name = QCOW2_OPT_L2_CACHE_ENTRY_SIZE, |
| .type = QEMU_OPT_SIZE, |
| .help = "Size of each entry in the L2 cache", |
| }, |
| { |
| .name = QCOW2_OPT_REFCOUNT_CACHE_SIZE, |
| .type = QEMU_OPT_SIZE, |
| .help = "Maximum refcount block cache size", |
| }, |
| { |
| .name = QCOW2_OPT_CACHE_CLEAN_INTERVAL, |
| .type = QEMU_OPT_NUMBER, |
| .help = "Clean unused cache entries after this time (in seconds)", |
| }, |
| BLOCK_CRYPTO_OPT_DEF_KEY_SECRET("encrypt.", |
| "ID of secret providing qcow2 AES key or LUKS passphrase"), |
| { /* end of list */ } |
| }, |
| }; |
| |
| static const char *overlap_bool_option_names[QCOW2_OL_MAX_BITNR] = { |
| [QCOW2_OL_MAIN_HEADER_BITNR] = QCOW2_OPT_OVERLAP_MAIN_HEADER, |
| [QCOW2_OL_ACTIVE_L1_BITNR] = QCOW2_OPT_OVERLAP_ACTIVE_L1, |
| [QCOW2_OL_ACTIVE_L2_BITNR] = QCOW2_OPT_OVERLAP_ACTIVE_L2, |
| [QCOW2_OL_REFCOUNT_TABLE_BITNR] = QCOW2_OPT_OVERLAP_REFCOUNT_TABLE, |
| [QCOW2_OL_REFCOUNT_BLOCK_BITNR] = QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK, |
| [QCOW2_OL_SNAPSHOT_TABLE_BITNR] = QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE, |
| [QCOW2_OL_INACTIVE_L1_BITNR] = QCOW2_OPT_OVERLAP_INACTIVE_L1, |
| [QCOW2_OL_INACTIVE_L2_BITNR] = QCOW2_OPT_OVERLAP_INACTIVE_L2, |
| [QCOW2_OL_BITMAP_DIRECTORY_BITNR] = QCOW2_OPT_OVERLAP_BITMAP_DIRECTORY, |
| }; |
| |
| static void cache_clean_timer_cb(void *opaque) |
| { |
| BlockDriverState *bs = opaque; |
| BDRVQcow2State *s = bs->opaque; |
| qcow2_cache_clean_unused(s->l2_table_cache); |
| qcow2_cache_clean_unused(s->refcount_block_cache); |
| timer_mod(s->cache_clean_timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + |
| (int64_t) s->cache_clean_interval * 1000); |
| } |
| |
| static void cache_clean_timer_init(BlockDriverState *bs, AioContext *context) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| if (s->cache_clean_interval > 0) { |
| s->cache_clean_timer = |
| aio_timer_new_with_attrs(context, QEMU_CLOCK_VIRTUAL, |
| SCALE_MS, QEMU_TIMER_ATTR_EXTERNAL, |
| cache_clean_timer_cb, bs); |
| timer_mod(s->cache_clean_timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + |
| (int64_t) s->cache_clean_interval * 1000); |
| } |
| } |
| |
| static void cache_clean_timer_del(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| if (s->cache_clean_timer) { |
| timer_free(s->cache_clean_timer); |
| s->cache_clean_timer = NULL; |
| } |
| } |
| |
| static void qcow2_detach_aio_context(BlockDriverState *bs) |
| { |
| cache_clean_timer_del(bs); |
| } |
| |
| static void qcow2_attach_aio_context(BlockDriverState *bs, |
| AioContext *new_context) |
| { |
| cache_clean_timer_init(bs, new_context); |
| } |
| |
| static bool read_cache_sizes(BlockDriverState *bs, QemuOpts *opts, |
| uint64_t *l2_cache_size, |
| uint64_t *l2_cache_entry_size, |
| uint64_t *refcount_cache_size, Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| uint64_t combined_cache_size, l2_cache_max_setting; |
| bool l2_cache_size_set, refcount_cache_size_set, combined_cache_size_set; |
| bool l2_cache_entry_size_set; |
| int min_refcount_cache = MIN_REFCOUNT_CACHE_SIZE * s->cluster_size; |
| uint64_t virtual_disk_size = bs->total_sectors * BDRV_SECTOR_SIZE; |
| uint64_t max_l2_entries = DIV_ROUND_UP(virtual_disk_size, s->cluster_size); |
| /* An L2 table is always one cluster in size so the max cache size |
| * should be a multiple of the cluster size. */ |
| uint64_t max_l2_cache = ROUND_UP(max_l2_entries * l2_entry_size(s), |
| s->cluster_size); |
| |
| combined_cache_size_set = qemu_opt_get(opts, QCOW2_OPT_CACHE_SIZE); |
| l2_cache_size_set = qemu_opt_get(opts, QCOW2_OPT_L2_CACHE_SIZE); |
| refcount_cache_size_set = qemu_opt_get(opts, QCOW2_OPT_REFCOUNT_CACHE_SIZE); |
| l2_cache_entry_size_set = qemu_opt_get(opts, QCOW2_OPT_L2_CACHE_ENTRY_SIZE); |
| |
| combined_cache_size = qemu_opt_get_size(opts, QCOW2_OPT_CACHE_SIZE, 0); |
| l2_cache_max_setting = qemu_opt_get_size(opts, QCOW2_OPT_L2_CACHE_SIZE, |
| DEFAULT_L2_CACHE_MAX_SIZE); |
| *refcount_cache_size = qemu_opt_get_size(opts, |
| QCOW2_OPT_REFCOUNT_CACHE_SIZE, 0); |
| |
| *l2_cache_entry_size = qemu_opt_get_size( |
| opts, QCOW2_OPT_L2_CACHE_ENTRY_SIZE, s->cluster_size); |
| |
| *l2_cache_size = MIN(max_l2_cache, l2_cache_max_setting); |
| |
| if (combined_cache_size_set) { |
| if (l2_cache_size_set && refcount_cache_size_set) { |
| error_setg(errp, QCOW2_OPT_CACHE_SIZE ", " QCOW2_OPT_L2_CACHE_SIZE |
| " and " QCOW2_OPT_REFCOUNT_CACHE_SIZE " may not be set " |
| "at the same time"); |
| return false; |
| } else if (l2_cache_size_set && |
| (l2_cache_max_setting > combined_cache_size)) { |
| error_setg(errp, QCOW2_OPT_L2_CACHE_SIZE " may not exceed " |
| QCOW2_OPT_CACHE_SIZE); |
| return false; |
| } else if (*refcount_cache_size > combined_cache_size) { |
| error_setg(errp, QCOW2_OPT_REFCOUNT_CACHE_SIZE " may not exceed " |
| QCOW2_OPT_CACHE_SIZE); |
| return false; |
| } |
| |
| if (l2_cache_size_set) { |
| *refcount_cache_size = combined_cache_size - *l2_cache_size; |
| } else if (refcount_cache_size_set) { |
| *l2_cache_size = combined_cache_size - *refcount_cache_size; |
| } else { |
| /* Assign as much memory as possible to the L2 cache, and |
| * use the remainder for the refcount cache */ |
| if (combined_cache_size >= max_l2_cache + min_refcount_cache) { |
| *l2_cache_size = max_l2_cache; |
| *refcount_cache_size = combined_cache_size - *l2_cache_size; |
| } else { |
| *refcount_cache_size = |
| MIN(combined_cache_size, min_refcount_cache); |
| *l2_cache_size = combined_cache_size - *refcount_cache_size; |
| } |
| } |
| } |
| |
| /* |
| * If the L2 cache is not enough to cover the whole disk then |
| * default to 4KB entries. Smaller entries reduce the cost of |
| * loads and evictions and increase I/O performance. |
| */ |
| if (*l2_cache_size < max_l2_cache && !l2_cache_entry_size_set) { |
| *l2_cache_entry_size = MIN(s->cluster_size, 4096); |
| } |
| |
| /* l2_cache_size and refcount_cache_size are ensured to have at least |
| * their minimum values in qcow2_update_options_prepare() */ |
| |
| if (*l2_cache_entry_size < (1 << MIN_CLUSTER_BITS) || |
| *l2_cache_entry_size > s->cluster_size || |
| !is_power_of_2(*l2_cache_entry_size)) { |
| error_setg(errp, "L2 cache entry size must be a power of two " |
| "between %d and the cluster size (%d)", |
| 1 << MIN_CLUSTER_BITS, s->cluster_size); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| typedef struct Qcow2ReopenState { |
| Qcow2Cache *l2_table_cache; |
| Qcow2Cache *refcount_block_cache; |
| int l2_slice_size; /* Number of entries in a slice of the L2 table */ |
| bool use_lazy_refcounts; |
| int overlap_check; |
| bool discard_passthrough[QCOW2_DISCARD_MAX]; |
| uint64_t cache_clean_interval; |
| QCryptoBlockOpenOptions *crypto_opts; /* Disk encryption runtime options */ |
| } Qcow2ReopenState; |
| |
| static int qcow2_update_options_prepare(BlockDriverState *bs, |
| Qcow2ReopenState *r, |
| QDict *options, int flags, |
| Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| QemuOpts *opts = NULL; |
| const char *opt_overlap_check, *opt_overlap_check_template; |
| int overlap_check_template = 0; |
| uint64_t l2_cache_size, l2_cache_entry_size, refcount_cache_size; |
| int i; |
| const char *encryptfmt; |
| QDict *encryptopts = NULL; |
| int ret; |
| |
| qdict_extract_subqdict(options, &encryptopts, "encrypt."); |
| encryptfmt = qdict_get_try_str(encryptopts, "format"); |
| |
| opts = qemu_opts_create(&qcow2_runtime_opts, NULL, 0, &error_abort); |
| if (!qemu_opts_absorb_qdict(opts, options, errp)) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* get L2 table/refcount block cache size from command line options */ |
| if (!read_cache_sizes(bs, opts, &l2_cache_size, &l2_cache_entry_size, |
| &refcount_cache_size, errp)) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| l2_cache_size /= l2_cache_entry_size; |
| if (l2_cache_size < MIN_L2_CACHE_SIZE) { |
| l2_cache_size = MIN_L2_CACHE_SIZE; |
| } |
| if (l2_cache_size > INT_MAX) { |
| error_setg(errp, "L2 cache size too big"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| refcount_cache_size /= s->cluster_size; |
| if (refcount_cache_size < MIN_REFCOUNT_CACHE_SIZE) { |
| refcount_cache_size = MIN_REFCOUNT_CACHE_SIZE; |
| } |
| if (refcount_cache_size > INT_MAX) { |
| error_setg(errp, "Refcount cache size too big"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* alloc new L2 table/refcount block cache, flush old one */ |
| if (s->l2_table_cache) { |
| ret = qcow2_cache_flush(bs, s->l2_table_cache); |
| if (ret) { |
| error_setg_errno(errp, -ret, "Failed to flush the L2 table cache"); |
| goto fail; |
| } |
| } |
| |
| if (s->refcount_block_cache) { |
| ret = qcow2_cache_flush(bs, s->refcount_block_cache); |
| if (ret) { |
| error_setg_errno(errp, -ret, |
| "Failed to flush the refcount block cache"); |
| goto fail; |
| } |
| } |
| |
| r->l2_slice_size = l2_cache_entry_size / l2_entry_size(s); |
| r->l2_table_cache = qcow2_cache_create(bs, l2_cache_size, |
| l2_cache_entry_size); |
| r->refcount_block_cache = qcow2_cache_create(bs, refcount_cache_size, |
| s->cluster_size); |
| if (r->l2_table_cache == NULL || r->refcount_block_cache == NULL) { |
| error_setg(errp, "Could not allocate metadata caches"); |
| ret = -ENOMEM; |
| goto fail; |
| } |
| |
| /* New interval for cache cleanup timer */ |
| r->cache_clean_interval = |
| qemu_opt_get_number(opts, QCOW2_OPT_CACHE_CLEAN_INTERVAL, |
| DEFAULT_CACHE_CLEAN_INTERVAL); |
| #ifndef CONFIG_LINUX |
| if (r->cache_clean_interval != 0) { |
| error_setg(errp, QCOW2_OPT_CACHE_CLEAN_INTERVAL |
| " not supported on this host"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| #endif |
| if (r->cache_clean_interval > UINT_MAX) { |
| error_setg(errp, "Cache clean interval too big"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* lazy-refcounts; flush if going from enabled to disabled */ |
| r->use_lazy_refcounts = qemu_opt_get_bool(opts, QCOW2_OPT_LAZY_REFCOUNTS, |
| (s->compatible_features & QCOW2_COMPAT_LAZY_REFCOUNTS)); |
| if (r->use_lazy_refcounts && s->qcow_version < 3) { |
| error_setg(errp, "Lazy refcounts require a qcow2 image with at least " |
| "qemu 1.1 compatibility level"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| if (s->use_lazy_refcounts && !r->use_lazy_refcounts) { |
| ret = qcow2_mark_clean(bs); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to disable lazy refcounts"); |
| goto fail; |
| } |
| } |
| |
| /* Overlap check options */ |
| opt_overlap_check = qemu_opt_get(opts, QCOW2_OPT_OVERLAP); |
| opt_overlap_check_template = qemu_opt_get(opts, QCOW2_OPT_OVERLAP_TEMPLATE); |
| if (opt_overlap_check_template && opt_overlap_check && |
| strcmp(opt_overlap_check_template, opt_overlap_check)) |
| { |
| error_setg(errp, "Conflicting values for qcow2 options '" |
| QCOW2_OPT_OVERLAP "' ('%s') and '" QCOW2_OPT_OVERLAP_TEMPLATE |
| "' ('%s')", opt_overlap_check, opt_overlap_check_template); |
| ret = -EINVAL; |
| goto fail; |
| } |
| if (!opt_overlap_check) { |
| opt_overlap_check = opt_overlap_check_template ?: "cached"; |
| } |
| |
| if (!strcmp(opt_overlap_check, "none")) { |
| overlap_check_template = 0; |
| } else if (!strcmp(opt_overlap_check, "constant")) { |
| overlap_check_template = QCOW2_OL_CONSTANT; |
| } else if (!strcmp(opt_overlap_check, "cached")) { |
| overlap_check_template = QCOW2_OL_CACHED; |
| } else if (!strcmp(opt_overlap_check, "all")) { |
| overlap_check_template = QCOW2_OL_ALL; |
| } else { |
| error_setg(errp, "Unsupported value '%s' for qcow2 option " |
| "'overlap-check'. Allowed are any of the following: " |
| "none, constant, cached, all", opt_overlap_check); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| r->overlap_check = 0; |
| for (i = 0; i < QCOW2_OL_MAX_BITNR; i++) { |
| /* overlap-check defines a template bitmask, but every flag may be |
| * overwritten through the associated boolean option */ |
| r->overlap_check |= |
| qemu_opt_get_bool(opts, overlap_bool_option_names[i], |
| overlap_check_template & (1 << i)) << i; |
| } |
| |
| r->discard_passthrough[QCOW2_DISCARD_NEVER] = false; |
| r->discard_passthrough[QCOW2_DISCARD_ALWAYS] = true; |
| r->discard_passthrough[QCOW2_DISCARD_REQUEST] = |
| qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_REQUEST, |
| flags & BDRV_O_UNMAP); |
| r->discard_passthrough[QCOW2_DISCARD_SNAPSHOT] = |
| qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_SNAPSHOT, true); |
| r->discard_passthrough[QCOW2_DISCARD_OTHER] = |
| qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_OTHER, false); |
| |
| switch (s->crypt_method_header) { |
| case QCOW_CRYPT_NONE: |
| if (encryptfmt) { |
| error_setg(errp, "No encryption in image header, but options " |
| "specified format '%s'", encryptfmt); |
| ret = -EINVAL; |
| goto fail; |
| } |
| break; |
| |
| case QCOW_CRYPT_AES: |
| if (encryptfmt && !g_str_equal(encryptfmt, "aes")) { |
| error_setg(errp, |
| "Header reported 'aes' encryption format but " |
| "options specify '%s'", encryptfmt); |
| ret = -EINVAL; |
| goto fail; |
| } |
| qdict_put_str(encryptopts, "format", "qcow"); |
| r->crypto_opts = block_crypto_open_opts_init(encryptopts, errp); |
| if (!r->crypto_opts) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| break; |
| |
| case QCOW_CRYPT_LUKS: |
| if (encryptfmt && !g_str_equal(encryptfmt, "luks")) { |
| error_setg(errp, |
| "Header reported 'luks' encryption format but " |
| "options specify '%s'", encryptfmt); |
| ret = -EINVAL; |
| goto fail; |
| } |
| qdict_put_str(encryptopts, "format", "luks"); |
| r->crypto_opts = block_crypto_open_opts_init(encryptopts, errp); |
| if (!r->crypto_opts) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| break; |
| |
| default: |
| error_setg(errp, "Unsupported encryption method %d", |
| s->crypt_method_header); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| ret = 0; |
| fail: |
| qobject_unref(encryptopts); |
| qemu_opts_del(opts); |
| opts = NULL; |
| return ret; |
| } |
| |
| static void qcow2_update_options_commit(BlockDriverState *bs, |
| Qcow2ReopenState *r) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int i; |
| |
| if (s->l2_table_cache) { |
| qcow2_cache_destroy(s->l2_table_cache); |
| } |
| if (s->refcount_block_cache) { |
| qcow2_cache_destroy(s->refcount_block_cache); |
| } |
| s->l2_table_cache = r->l2_table_cache; |
| s->refcount_block_cache = r->refcount_block_cache; |
| s->l2_slice_size = r->l2_slice_size; |
| |
| s->overlap_check = r->overlap_check; |
| s->use_lazy_refcounts = r->use_lazy_refcounts; |
| |
| for (i = 0; i < QCOW2_DISCARD_MAX; i++) { |
| s->discard_passthrough[i] = r->discard_passthrough[i]; |
| } |
| |
| if (s->cache_clean_interval != r->cache_clean_interval) { |
| cache_clean_timer_del(bs); |
| s->cache_clean_interval = r->cache_clean_interval; |
| cache_clean_timer_init(bs, bdrv_get_aio_context(bs)); |
| } |
| |
| qapi_free_QCryptoBlockOpenOptions(s->crypto_opts); |
| s->crypto_opts = r->crypto_opts; |
| } |
| |
| static void qcow2_update_options_abort(BlockDriverState *bs, |
| Qcow2ReopenState *r) |
| { |
| if (r->l2_table_cache) { |
| qcow2_cache_destroy(r->l2_table_cache); |
| } |
| if (r->refcount_block_cache) { |
| qcow2_cache_destroy(r->refcount_block_cache); |
| } |
| qapi_free_QCryptoBlockOpenOptions(r->crypto_opts); |
| } |
| |
| static int qcow2_update_options(BlockDriverState *bs, QDict *options, |
| int flags, Error **errp) |
| { |
| Qcow2ReopenState r = {}; |
| int ret; |
| |
| ret = qcow2_update_options_prepare(bs, &r, options, flags, errp); |
| if (ret >= 0) { |
| qcow2_update_options_commit(bs, &r); |
| } else { |
| qcow2_update_options_abort(bs, &r); |
| } |
| |
| return ret; |
| } |
| |
| static int validate_compression_type(BDRVQcow2State *s, Error **errp) |
| { |
| switch (s->compression_type) { |
| case QCOW2_COMPRESSION_TYPE_ZLIB: |
| #ifdef CONFIG_ZSTD |
| case QCOW2_COMPRESSION_TYPE_ZSTD: |
| #endif |
| break; |
| |
| default: |
| error_setg(errp, "qcow2: unknown compression type: %u", |
| s->compression_type); |
| return -ENOTSUP; |
| } |
| |
| /* |
| * if the compression type differs from QCOW2_COMPRESSION_TYPE_ZLIB |
| * the incompatible feature flag must be set |
| */ |
| if (s->compression_type == QCOW2_COMPRESSION_TYPE_ZLIB) { |
| if (s->incompatible_features & QCOW2_INCOMPAT_COMPRESSION) { |
| error_setg(errp, "qcow2: Compression type incompatible feature " |
| "bit must not be set"); |
| return -EINVAL; |
| } |
| } else { |
| if (!(s->incompatible_features & QCOW2_INCOMPAT_COMPRESSION)) { |
| error_setg(errp, "qcow2: Compression type incompatible feature " |
| "bit must be set"); |
| return -EINVAL; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /* Called with s->lock held. */ |
| static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options, |
| int flags, Error **errp) |
| { |
| ERRP_GUARD(); |
| BDRVQcow2State *s = bs->opaque; |
| unsigned int len, i; |
| int ret = 0; |
| QCowHeader header; |
| uint64_t ext_end; |
| uint64_t l1_vm_state_index; |
| bool update_header = false; |
| |
| ret = bdrv_pread(bs->file, 0, &header, sizeof(header)); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not read qcow2 header"); |
| goto fail; |
| } |
| header.magic = be32_to_cpu(header.magic); |
| header.version = be32_to_cpu(header.version); |
| header.backing_file_offset = be64_to_cpu(header.backing_file_offset); |
| header.backing_file_size = be32_to_cpu(header.backing_file_size); |
| header.size = be64_to_cpu(header.size); |
| header.cluster_bits = be32_to_cpu(header.cluster_bits); |
| header.crypt_method = be32_to_cpu(header.crypt_method); |
| header.l1_table_offset = be64_to_cpu(header.l1_table_offset); |
| header.l1_size = be32_to_cpu(header.l1_size); |
| header.refcount_table_offset = be64_to_cpu(header.refcount_table_offset); |
| header.refcount_table_clusters = |
| be32_to_cpu(header.refcount_table_clusters); |
| header.snapshots_offset = be64_to_cpu(header.snapshots_offset); |
| header.nb_snapshots = be32_to_cpu(header.nb_snapshots); |
| |
| if (header.magic != QCOW_MAGIC) { |
| error_setg(errp, "Image is not in qcow2 format"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| if (header.version < 2 || header.version > 3) { |
| error_setg(errp, "Unsupported qcow2 version %" PRIu32, header.version); |
| ret = -ENOTSUP; |
| goto fail; |
| } |
| |
| s->qcow_version = header.version; |
| |
| /* Initialise cluster size */ |
| if (header.cluster_bits < MIN_CLUSTER_BITS || |
| header.cluster_bits > MAX_CLUSTER_BITS) { |
| error_setg(errp, "Unsupported cluster size: 2^%" PRIu32, |
| header.cluster_bits); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| s->cluster_bits = header.cluster_bits; |
| s->cluster_size = 1 << s->cluster_bits; |
| |
| /* Initialise version 3 header fields */ |
| if (header.version == 2) { |
| header.incompatible_features = 0; |
| header.compatible_features = 0; |
| header.autoclear_features = 0; |
| header.refcount_order = 4; |
| header.header_length = 72; |
| } else { |
| header.incompatible_features = |
| be64_to_cpu(header.incompatible_features); |
| header.compatible_features = be64_to_cpu(header.compatible_features); |
| header.autoclear_features = be64_to_cpu(header.autoclear_features); |
| header.refcount_order = be32_to_cpu(header.refcount_order); |
| header.header_length = be32_to_cpu(header.header_length); |
| |
| if (header.header_length < 104) { |
| error_setg(errp, "qcow2 header too short"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| } |
| |
| if (header.header_length > s->cluster_size) { |
| error_setg(errp, "qcow2 header exceeds cluster size"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| if (header.header_length > sizeof(header)) { |
| s->unknown_header_fields_size = header.header_length - sizeof(header); |
| s->unknown_header_fields = g_malloc(s->unknown_header_fields_size); |
| ret = bdrv_pread(bs->file, sizeof(header), s->unknown_header_fields, |
| s->unknown_header_fields_size); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not read unknown qcow2 header " |
| "fields"); |
| goto fail; |
| } |
| } |
| |
| if (header.backing_file_offset > s->cluster_size) { |
| error_setg(errp, "Invalid backing file offset"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| if (header.backing_file_offset) { |
| ext_end = header.backing_file_offset; |
| } else { |
| ext_end = 1 << header.cluster_bits; |
| } |
| |
| /* Handle feature bits */ |
| s->incompatible_features = header.incompatible_features; |
| s->compatible_features = header.compatible_features; |
| s->autoclear_features = header.autoclear_features; |
| |
| /* |
| * Handle compression type |
| * Older qcow2 images don't contain the compression type header. |
| * Distinguish them by the header length and use |
| * the only valid (default) compression type in that case |
| */ |
| if (header.header_length > offsetof(QCowHeader, compression_type)) { |
| s->compression_type = header.compression_type; |
| } else { |
| s->compression_type = QCOW2_COMPRESSION_TYPE_ZLIB; |
| } |
| |
| ret = validate_compression_type(s, errp); |
| if (ret) { |
| goto fail; |
| } |
| |
| if (s->incompatible_features & ~QCOW2_INCOMPAT_MASK) { |
| void *feature_table = NULL; |
| qcow2_read_extensions(bs, header.header_length, ext_end, |
| &feature_table, flags, NULL, NULL); |
| report_unsupported_feature(errp, feature_table, |
| s->incompatible_features & |
| ~QCOW2_INCOMPAT_MASK); |
| ret = -ENOTSUP; |
| g_free(feature_table); |
| goto fail; |
| } |
| |
| if (s->incompatible_features & QCOW2_INCOMPAT_CORRUPT) { |
| /* Corrupt images may not be written to unless they are being repaired |
| */ |
| if ((flags & BDRV_O_RDWR) && !(flags & BDRV_O_CHECK)) { |
| error_setg(errp, "qcow2: Image is corrupt; cannot be opened " |
| "read/write"); |
| ret = -EACCES; |
| goto fail; |
| } |
| } |
| |
| s->subclusters_per_cluster = |
| has_subclusters(s) ? QCOW_EXTL2_SUBCLUSTERS_PER_CLUSTER : 1; |
| s->subcluster_size = s->cluster_size / s->subclusters_per_cluster; |
| s->subcluster_bits = ctz32(s->subcluster_size); |
| |
| if (s->subcluster_size < (1 << MIN_CLUSTER_BITS)) { |
| error_setg(errp, "Unsupported subcluster size: %d", s->subcluster_size); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* Check support for various header values */ |
| if (header.refcount_order > 6) { |
| error_setg(errp, "Reference count entry width too large; may not " |
| "exceed 64 bits"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| s->refcount_order = header.refcount_order; |
| s->refcount_bits = 1 << s->refcount_order; |
| s->refcount_max = UINT64_C(1) << (s->refcount_bits - 1); |
| s->refcount_max += s->refcount_max - 1; |
| |
| s->crypt_method_header = header.crypt_method; |
| if (s->crypt_method_header) { |
| if (bdrv_uses_whitelist() && |
| s->crypt_method_header == QCOW_CRYPT_AES) { |
| error_setg(errp, |
| "Use of AES-CBC encrypted qcow2 images is no longer " |
| "supported in system emulators"); |
| error_append_hint(errp, |
| "You can use 'qemu-img convert' to convert your " |
| "image to an alternative supported format, such " |
| "as unencrypted qcow2, or raw with the LUKS " |
| "format instead.\n"); |
| ret = -ENOSYS; |
| goto fail; |
| } |
| |
| if (s->crypt_method_header == QCOW_CRYPT_AES) { |
| s->crypt_physical_offset = false; |
| } else { |
| /* Assuming LUKS and any future crypt methods we |
| * add will all use physical offsets, due to the |
| * fact that the alternative is insecure... */ |
| s->crypt_physical_offset = true; |
| } |
| |
| bs->encrypted = true; |
| } |
| |
| s->l2_bits = s->cluster_bits - ctz32(l2_entry_size(s)); |
| s->l2_size = 1 << s->l2_bits; |
| /* 2^(s->refcount_order - 3) is the refcount width in bytes */ |
| s->refcount_block_bits = s->cluster_bits - (s->refcount_order - 3); |
| s->refcount_block_size = 1 << s->refcount_block_bits; |
| bs->total_sectors = header.size / BDRV_SECTOR_SIZE; |
| s->csize_shift = (62 - (s->cluster_bits - 8)); |
| s->csize_mask = (1 << (s->cluster_bits - 8)) - 1; |
| s->cluster_offset_mask = (1LL << s->csize_shift) - 1; |
| |
| s->refcount_table_offset = header.refcount_table_offset; |
| s->refcount_table_size = |
| header.refcount_table_clusters << (s->cluster_bits - 3); |
| |
| if (header.refcount_table_clusters == 0 && !(flags & BDRV_O_CHECK)) { |
| error_setg(errp, "Image does not contain a reference count table"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| ret = qcow2_validate_table(bs, s->refcount_table_offset, |
| header.refcount_table_clusters, |
| s->cluster_size, QCOW_MAX_REFTABLE_SIZE, |
| "Reference count table", errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| if (!(flags & BDRV_O_CHECK)) { |
| /* |
| * The total size in bytes of the snapshot table is checked in |
| * qcow2_read_snapshots() because the size of each snapshot is |
| * variable and we don't know it yet. |
| * Here we only check the offset and number of snapshots. |
| */ |
| ret = qcow2_validate_table(bs, header.snapshots_offset, |
| header.nb_snapshots, |
| sizeof(QCowSnapshotHeader), |
| sizeof(QCowSnapshotHeader) * |
| QCOW_MAX_SNAPSHOTS, |
| "Snapshot table", errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| } |
| |
| /* read the level 1 table */ |
| ret = qcow2_validate_table(bs, header.l1_table_offset, |
| header.l1_size, L1E_SIZE, |
| QCOW_MAX_L1_SIZE, "Active L1 table", errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| s->l1_size = header.l1_size; |
| s->l1_table_offset = header.l1_table_offset; |
| |
| l1_vm_state_index = size_to_l1(s, header.size); |
| if (l1_vm_state_index > INT_MAX) { |
| error_setg(errp, "Image is too big"); |
| ret = -EFBIG; |
| goto fail; |
| } |
| s->l1_vm_state_index = l1_vm_state_index; |
| |
| /* the L1 table must contain at least enough entries to put |
| header.size bytes */ |
| if (s->l1_size < s->l1_vm_state_index) { |
| error_setg(errp, "L1 table is too small"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| if (s->l1_size > 0) { |
| s->l1_table = qemu_try_blockalign(bs->file->bs, s->l1_size * L1E_SIZE); |
| if (s->l1_table == NULL) { |
| error_setg(errp, "Could not allocate L1 table"); |
| ret = -ENOMEM; |
| goto fail; |
| } |
| ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table, |
| s->l1_size * L1E_SIZE); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not read L1 table"); |
| goto fail; |
| } |
| for(i = 0;i < s->l1_size; i++) { |
| s->l1_table[i] = be64_to_cpu(s->l1_table[i]); |
| } |
| } |
| |
| /* Parse driver-specific options */ |
| ret = qcow2_update_options(bs, options, flags, errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| s->flags = flags; |
| |
| ret = qcow2_refcount_init(bs); |
| if (ret != 0) { |
| error_setg_errno(errp, -ret, "Could not initialize refcount handling"); |
| goto fail; |
| } |
| |
| QLIST_INIT(&s->cluster_allocs); |
| QTAILQ_INIT(&s->discards); |
| |
| /* read qcow2 extensions */ |
| if (qcow2_read_extensions(bs, header.header_length, ext_end, NULL, |
| flags, &update_header, errp)) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* Open external data file */ |
| s->data_file = bdrv_open_child(NULL, options, "data-file", bs, |
| &child_of_bds, BDRV_CHILD_DATA, |
| true, errp); |
| if (*errp) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| if (s->incompatible_features & QCOW2_INCOMPAT_DATA_FILE) { |
| if (!s->data_file && s->image_data_file) { |
| s->data_file = bdrv_open_child(s->image_data_file, options, |
| "data-file", bs, &child_of_bds, |
| BDRV_CHILD_DATA, false, errp); |
| if (!s->data_file) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| } |
| if (!s->data_file) { |
| error_setg(errp, "'data-file' is required for this image"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* No data here */ |
| bs->file->role &= ~BDRV_CHILD_DATA; |
| |
| /* Must succeed because we have given up permissions if anything */ |
| bdrv_child_refresh_perms(bs, bs->file, &error_abort); |
| } else { |
| if (s->data_file) { |
| error_setg(errp, "'data-file' can only be set for images with an " |
| "external data file"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| s->data_file = bs->file; |
| |
| if (data_file_is_raw(bs)) { |
| error_setg(errp, "data-file-raw requires a data file"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| } |
| |
| /* qcow2_read_extension may have set up the crypto context |
| * if the crypt method needs a header region, some methods |
| * don't need header extensions, so must check here |
| */ |
| if (s->crypt_method_header && !s->crypto) { |
| if (s->crypt_method_header == QCOW_CRYPT_AES) { |
| unsigned int cflags = 0; |
| if (flags & BDRV_O_NO_IO) { |
| cflags |= QCRYPTO_BLOCK_OPEN_NO_IO; |
| } |
| s->crypto = qcrypto_block_open(s->crypto_opts, "encrypt.", |
| NULL, NULL, cflags, |
| QCOW2_MAX_THREADS, errp); |
| if (!s->crypto) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| } else if (!(flags & BDRV_O_NO_IO)) { |
| error_setg(errp, "Missing CRYPTO header for crypt method %d", |
| s->crypt_method_header); |
| ret = -EINVAL; |
| goto fail; |
| } |
| } |
| |
| /* read the backing file name */ |
| if (header.backing_file_offset != 0) { |
| len = header.backing_file_size; |
| if (len > MIN(1023, s->cluster_size - header.backing_file_offset) || |
| len >= sizeof(bs->backing_file)) { |
| error_setg(errp, "Backing file name too long"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| ret = bdrv_pread(bs->file, header.backing_file_offset, |
| bs->auto_backing_file, len); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not read backing file name"); |
| goto fail; |
| } |
| bs->auto_backing_file[len] = '\0'; |
| pstrcpy(bs->backing_file, sizeof(bs->backing_file), |
| bs->auto_backing_file); |
| s->image_backing_file = g_strdup(bs->auto_backing_file); |
| } |
| |
| /* |
| * Internal snapshots; skip reading them in check mode, because |
| * we do not need them then, and we do not want to abort because |
| * of a broken table. |
| */ |
| if (!(flags & BDRV_O_CHECK)) { |
| s->snapshots_offset = header.snapshots_offset; |
| s->nb_snapshots = header.nb_snapshots; |
| |
| ret = qcow2_read_snapshots(bs, errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| } |
| |
| /* Clear unknown autoclear feature bits */ |
| update_header |= s->autoclear_features & ~QCOW2_AUTOCLEAR_MASK; |
| update_header = |
| update_header && !bs->read_only && !(flags & BDRV_O_INACTIVE); |
| if (update_header) { |
| s->autoclear_features &= QCOW2_AUTOCLEAR_MASK; |
| } |
| |
| /* == Handle persistent dirty bitmaps == |
| * |
| * We want load dirty bitmaps in three cases: |
| * |
| * 1. Normal open of the disk in active mode, not related to invalidation |
| * after migration. |
| * |
| * 2. Invalidation of the target vm after pre-copy phase of migration, if |
| * bitmaps are _not_ migrating through migration channel, i.e. |
| * 'dirty-bitmaps' capability is disabled. |
| * |
| * 3. Invalidation of source vm after failed or canceled migration. |
| * This is a very interesting case. There are two possible types of |
| * bitmaps: |
| * |
| * A. Stored on inactivation and removed. They should be loaded from the |
| * image. |
| * |
| * B. Not stored: not-persistent bitmaps and bitmaps, migrated through |
| * the migration channel (with dirty-bitmaps capability). |
| * |
| * On the other hand, there are two possible sub-cases: |
| * |
| * 3.1 disk was changed by somebody else while were inactive. In this |
| * case all in-RAM dirty bitmaps (both persistent and not) are |
| * definitely invalid. And we don't have any method to determine |
| * this. |
| * |
| * Simple and safe thing is to just drop all the bitmaps of type B on |
| * inactivation. But in this case we lose bitmaps in valid 4.2 case. |
| * |
| * On the other hand, resuming source vm, if disk was already changed |
| * is a bad thing anyway: not only bitmaps, the whole vm state is |
| * out of sync with disk. |
| * |
| * This means, that user or management tool, who for some reason |
| * decided to resume source vm, after disk was already changed by |
| * target vm, should at least drop all dirty bitmaps by hand. |
| * |
| * So, we can ignore this case for now, but TODO: "generation" |
| * extension for qcow2, to determine, that image was changed after |
| * last inactivation. And if it is changed, we will drop (or at least |
| * mark as 'invalid' all the bitmaps of type B, both persistent |
| * and not). |
| * |
| * 3.2 disk was _not_ changed while were inactive. Bitmaps may be saved |
| * to disk ('dirty-bitmaps' capability disabled), or not saved |
| * ('dirty-bitmaps' capability enabled), but we don't need to care |
| * of: let's load bitmaps as always: stored bitmaps will be loaded, |
| * and not stored has flag IN_USE=1 in the image and will be skipped |
| * on loading. |
| * |
| * One remaining possible case when we don't want load bitmaps: |
| * |
| * 4. Open disk in inactive mode in target vm (bitmaps are migrating or |
| * will be loaded on invalidation, no needs try loading them before) |
| */ |
| |
| if (!(bdrv_get_flags(bs) & BDRV_O_INACTIVE)) { |
| /* It's case 1, 2 or 3.2. Or 3.1 which is BUG in management layer. */ |
| bool header_updated; |
| if (!qcow2_load_dirty_bitmaps(bs, &header_updated, errp)) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| update_header = update_header && !header_updated; |
| } |
| |
| if (update_header) { |
| ret = qcow2_update_header(bs); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not update qcow2 header"); |
| goto fail; |
| } |
| } |
| |
| bs->supported_zero_flags = header.version >= 3 ? |
| BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK : 0; |
| bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE; |
| |
| /* Repair image if dirty */ |
| if (!(flags & (BDRV_O_CHECK | BDRV_O_INACTIVE)) && !bs->read_only && |
| (s->incompatible_features & QCOW2_INCOMPAT_DIRTY)) { |
| BdrvCheckResult result = {0}; |
| |
| ret = qcow2_co_check_locked(bs, &result, |
| BDRV_FIX_ERRORS | BDRV_FIX_LEAKS); |
| if (ret < 0 || result.check_errors) { |
| if (ret >= 0) { |
| ret = -EIO; |
| } |
| error_setg_errno(errp, -ret, "Could not repair dirty image"); |
| goto fail; |
| } |
| } |
| |
| #ifdef DEBUG_ALLOC |
| { |
| BdrvCheckResult result = {0}; |
| qcow2_check_refcounts(bs, &result, 0); |
| } |
| #endif |
| |
| qemu_co_queue_init(&s->thread_task_queue); |
| |
| return ret; |
| |
| fail: |
| g_free(s->image_data_file); |
| if (has_data_file(bs)) { |
| bdrv_unref_child(bs, s->data_file); |
| s->data_file = NULL; |
| } |
| g_free(s->unknown_header_fields); |
| cleanup_unknown_header_ext(bs); |
| qcow2_free_snapshots(bs); |
| qcow2_refcount_close(bs); |
| qemu_vfree(s->l1_table); |
| /* else pre-write overlap checks in cache_destroy may crash */ |
| s->l1_table = NULL; |
| cache_clean_timer_del(bs); |
| if (s->l2_table_cache) { |
| qcow2_cache_destroy(s->l2_table_cache); |
| } |
| if (s->refcount_block_cache) { |
| qcow2_cache_destroy(s->refcount_block_cache); |
| } |
| qcrypto_block_free(s->crypto); |
| qapi_free_QCryptoBlockOpenOptions(s->crypto_opts); |
| return ret; |
| } |
| |
| typedef struct QCow2OpenCo { |
| BlockDriverState *bs; |
| QDict *options; |
| int flags; |
| Error **errp; |
| int ret; |
| } QCow2OpenCo; |
| |
| static void coroutine_fn qcow2_open_entry(void *opaque) |
| { |
| QCow2OpenCo *qoc = opaque; |
| BDRVQcow2State *s = qoc->bs->opaque; |
| |
| qemu_co_mutex_lock(&s->lock); |
| qoc->ret = qcow2_do_open(qoc->bs, qoc->options, qoc->flags, qoc->errp); |
| qemu_co_mutex_unlock(&s->lock); |
| } |
| |
| static int qcow2_open(BlockDriverState *bs, QDict *options, int flags, |
| Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| QCow2OpenCo qoc = { |
| .bs = bs, |
| .options = options, |
| .flags = flags, |
| .errp = errp, |
| .ret = -EINPROGRESS |
| }; |
| |
| bs->file = bdrv_open_child(NULL, options, "file", bs, &child_of_bds, |
| BDRV_CHILD_IMAGE, false, errp); |
| if (!bs->file) { |
| return -EINVAL; |
| } |
| |
| /* Initialise locks */ |
| qemu_co_mutex_init(&s->lock); |
| |
| if (qemu_in_coroutine()) { |
| /* From bdrv_co_create. */ |
| qcow2_open_entry(&qoc); |
| } else { |
| assert(qemu_get_current_aio_context() == qemu_get_aio_context()); |
| qemu_coroutine_enter(qemu_coroutine_create(qcow2_open_entry, &qoc)); |
| BDRV_POLL_WHILE(bs, qoc.ret == -EINPROGRESS); |
| } |
| return qoc.ret; |
| } |
| |
| static void qcow2_refresh_limits(BlockDriverState *bs, Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| |
| if (bs->encrypted) { |
| /* Encryption works on a sector granularity */ |
| bs->bl.request_alignment = qcrypto_block_get_sector_size(s->crypto); |
| } |
| bs->bl.pwrite_zeroes_alignment = s->subcluster_size; |
| bs->bl.pdiscard_alignment = s->cluster_size; |
| } |
| |
| static int qcow2_reopen_prepare(BDRVReopenState *state, |
| BlockReopenQueue *queue, Error **errp) |
| { |
| Qcow2ReopenState *r; |
| int ret; |
| |
| r = g_new0(Qcow2ReopenState, 1); |
| state->opaque = r; |
| |
| ret = qcow2_update_options_prepare(state->bs, r, state->options, |
| state->flags, errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| /* We need to write out any unwritten data if we reopen read-only. */ |
| if ((state->flags & BDRV_O_RDWR) == 0) { |
| ret = qcow2_reopen_bitmaps_ro(state->bs, errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = bdrv_flush(state->bs); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = qcow2_mark_clean(state->bs); |
| if (ret < 0) { |
| goto fail; |
| } |
| } |
| |
| return 0; |
| |
| fail: |
| qcow2_update_options_abort(state->bs, r); |
| g_free(r); |
| return ret; |
| } |
| |
| static void qcow2_reopen_commit(BDRVReopenState *state) |
| { |
| qcow2_update_options_commit(state->bs, state->opaque); |
| g_free(state->opaque); |
| } |
| |
| static void qcow2_reopen_commit_post(BDRVReopenState *state) |
| { |
| if (state->flags & BDRV_O_RDWR) { |
| Error *local_err = NULL; |
| |
| if (qcow2_reopen_bitmaps_rw(state->bs, &local_err) < 0) { |
| /* |
| * This is not fatal, bitmaps just left read-only, so all following |
| * writes will fail. User can remove read-only bitmaps to unblock |
| * writes or retry reopen. |
| */ |
| error_reportf_err(local_err, |
| "%s: Failed to make dirty bitmaps writable: ", |
| bdrv_get_node_name(state->bs)); |
| } |
| } |
| } |
| |
| static void qcow2_reopen_abort(BDRVReopenState *state) |
| { |
| qcow2_update_options_abort(state->bs, state->opaque); |
| g_free(state->opaque); |
| } |
| |
| static void qcow2_join_options(QDict *options, QDict *old_options) |
| { |
| bool has_new_overlap_template = |
| qdict_haskey(options, QCOW2_OPT_OVERLAP) || |
| qdict_haskey(options, QCOW2_OPT_OVERLAP_TEMPLATE); |
| bool has_new_total_cache_size = |
| qdict_haskey(options, QCOW2_OPT_CACHE_SIZE); |
| bool has_all_cache_options; |
| |
| /* New overlap template overrides all old overlap options */ |
| if (has_new_overlap_template) { |
| qdict_del(old_options, QCOW2_OPT_OVERLAP); |
| qdict_del(old_options, QCOW2_OPT_OVERLAP_TEMPLATE); |
| qdict_del(old_options, QCOW2_OPT_OVERLAP_MAIN_HEADER); |
| qdict_del(old_options, QCOW2_OPT_OVERLAP_ACTIVE_L1); |
| qdict_del(old_options, QCOW2_OPT_OVERLAP_ACTIVE_L2); |
| qdict_del(old_options, QCOW2_OPT_OVERLAP_REFCOUNT_TABLE); |
| qdict_del(old_options, QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK); |
| qdict_del(old_options, QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE); |
| qdict_del(old_options, QCOW2_OPT_OVERLAP_INACTIVE_L1); |
| qdict_del(old_options, QCOW2_OPT_OVERLAP_INACTIVE_L2); |
| } |
| |
| /* New total cache size overrides all old options */ |
| if (qdict_haskey(options, QCOW2_OPT_CACHE_SIZE)) { |
| qdict_del(old_options, QCOW2_OPT_L2_CACHE_SIZE); |
| qdict_del(old_options, QCOW2_OPT_REFCOUNT_CACHE_SIZE); |
| } |
| |
| qdict_join(options, old_options, false); |
| |
| /* |
| * If after merging all cache size options are set, an old total size is |
| * overwritten. Do keep all options, however, if all three are new. The |
| * resulting error message is what we want to happen. |
| */ |
| has_all_cache_options = |
| qdict_haskey(options, QCOW2_OPT_CACHE_SIZE) || |
| qdict_haskey(options, QCOW2_OPT_L2_CACHE_SIZE) || |
| qdict_haskey(options, QCOW2_OPT_REFCOUNT_CACHE_SIZE); |
| |
| if (has_all_cache_options && !has_new_total_cache_size) { |
| qdict_del(options, QCOW2_OPT_CACHE_SIZE); |
| } |
| } |
| |
| static int coroutine_fn qcow2_co_block_status(BlockDriverState *bs, |
| bool want_zero, |
| int64_t offset, int64_t count, |
| int64_t *pnum, int64_t *map, |
| BlockDriverState **file) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| uint64_t host_offset; |
| unsigned int bytes; |
| QCow2SubclusterType type; |
| int ret, status = 0; |
| |
| qemu_co_mutex_lock(&s->lock); |
| |
| if (!s->metadata_preallocation_checked) { |
| ret = qcow2_detect_metadata_preallocation(bs); |
| s->metadata_preallocation = (ret == 1); |
| s->metadata_preallocation_checked = true; |
| } |
| |
| bytes = MIN(INT_MAX, count); |
| ret = qcow2_get_host_offset(bs, offset, &bytes, &host_offset, &type); |
| qemu_co_mutex_unlock(&s->lock); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| *pnum = bytes; |
| |
| if ((type == QCOW2_SUBCLUSTER_NORMAL || |
| type == QCOW2_SUBCLUSTER_ZERO_ALLOC || |
| type == QCOW2_SUBCLUSTER_UNALLOCATED_ALLOC) && !s->crypto) { |
| *map = host_offset; |
| *file = s->data_file->bs; |
| status |= BDRV_BLOCK_OFFSET_VALID; |
| } |
| if (type == QCOW2_SUBCLUSTER_ZERO_PLAIN || |
| type == QCOW2_SUBCLUSTER_ZERO_ALLOC) { |
| status |= BDRV_BLOCK_ZERO; |
| } else if (type != QCOW2_SUBCLUSTER_UNALLOCATED_PLAIN && |
| type != QCOW2_SUBCLUSTER_UNALLOCATED_ALLOC) { |
| status |= BDRV_BLOCK_DATA; |
| } |
| if (s->metadata_preallocation && (status & BDRV_BLOCK_DATA) && |
| (status & BDRV_BLOCK_OFFSET_VALID)) |
| { |
| status |= BDRV_BLOCK_RECURSE; |
| } |
| return status; |
| } |
| |
| static coroutine_fn int qcow2_handle_l2meta(BlockDriverState *bs, |
| QCowL2Meta **pl2meta, |
| bool link_l2) |
| { |
| int ret = 0; |
| QCowL2Meta *l2meta = *pl2meta; |
| |
| while (l2meta != NULL) { |
| QCowL2Meta *next; |
| |
| if (link_l2) { |
| ret = qcow2_alloc_cluster_link_l2(bs, l2meta); |
| if (ret) { |
| goto out; |
| } |
| } else { |
| qcow2_alloc_cluster_abort(bs, l2meta); |
| } |
| |
| /* Take the request off the list of running requests */ |
| QLIST_REMOVE(l2meta, next_in_flight); |
| |
| qemu_co_queue_restart_all(&l2meta->dependent_requests); |
| |
| next = l2meta->next; |
| g_free(l2meta); |
| l2meta = next; |
| } |
| out: |
| *pl2meta = l2meta; |
| return ret; |
| } |
| |
| static coroutine_fn int |
| qcow2_co_preadv_encrypted(BlockDriverState *bs, |
| uint64_t host_offset, |
| uint64_t offset, |
| uint64_t bytes, |
| QEMUIOVector *qiov, |
| uint64_t qiov_offset) |
| { |
| int ret; |
| BDRVQcow2State *s = bs->opaque; |
| uint8_t *buf; |
| |
| assert(bs->encrypted && s->crypto); |
| assert(bytes <= QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); |
| |
| /* |
| * For encrypted images, read everything into a temporary |
| * contiguous buffer on which the AES functions can work. |
| * Also, decryption in a separate buffer is better as it |
| * prevents the guest from learning information about the |
| * encrypted nature of the virtual disk. |
| */ |
| |
| buf = qemu_try_blockalign(s->data_file->bs, bytes); |
| if (buf == NULL) { |
| return -ENOMEM; |
| } |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); |
| ret = bdrv_co_pread(s->data_file, host_offset, bytes, buf, 0); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| if (qcow2_co_decrypt(bs, host_offset, offset, buf, bytes) < 0) |
| { |
| ret = -EIO; |
| goto fail; |
| } |
| qemu_iovec_from_buf(qiov, qiov_offset, buf, bytes); |
| |
| fail: |
| qemu_vfree(buf); |
| |
| return ret; |
| } |
| |
| typedef struct Qcow2AioTask { |
| AioTask task; |
| |
| BlockDriverState *bs; |
| QCow2SubclusterType subcluster_type; /* only for read */ |
| uint64_t host_offset; /* or full descriptor in compressed clusters */ |
| uint64_t offset; |
| uint64_t bytes; |
| QEMUIOVector *qiov; |
| uint64_t qiov_offset; |
| QCowL2Meta *l2meta; /* only for write */ |
| } Qcow2AioTask; |
| |
| static coroutine_fn int qcow2_co_preadv_task_entry(AioTask *task); |
| static coroutine_fn int qcow2_add_task(BlockDriverState *bs, |
| AioTaskPool *pool, |
| AioTaskFunc func, |
| QCow2SubclusterType subcluster_type, |
| uint64_t host_offset, |
| uint64_t offset, |
| uint64_t bytes, |
| QEMUIOVector *qiov, |
| size_t qiov_offset, |
| QCowL2Meta *l2meta) |
| { |
| Qcow2AioTask local_task; |
| Qcow2AioTask *task = pool ? g_new(Qcow2AioTask, 1) : &local_task; |
| |
| *task = (Qcow2AioTask) { |
| .task.func = func, |
| .bs = bs, |
| .subcluster_type = subcluster_type, |
| .qiov = qiov, |
| .host_offset = host_offset, |
| .offset = offset, |
| .bytes = bytes, |
| .qiov_offset = qiov_offset, |
| .l2meta = l2meta, |
| }; |
| |
| trace_qcow2_add_task(qemu_coroutine_self(), bs, pool, |
| func == qcow2_co_preadv_task_entry ? "read" : "write", |
| subcluster_type, host_offset, offset, bytes, |
| qiov, qiov_offset); |
| |
| if (!pool) { |
| return func(&task->task); |
| } |
| |
| aio_task_pool_start_task(pool, &task->task); |
| |
| return 0; |
| } |
| |
| static coroutine_fn int qcow2_co_preadv_task(BlockDriverState *bs, |
| QCow2SubclusterType subc_type, |
| uint64_t host_offset, |
| uint64_t offset, uint64_t bytes, |
| QEMUIOVector *qiov, |
| size_t qiov_offset) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| |
| switch (subc_type) { |
| case QCOW2_SUBCLUSTER_ZERO_PLAIN: |
| case QCOW2_SUBCLUSTER_ZERO_ALLOC: |
| /* Both zero types are handled in qcow2_co_preadv_part */ |
| g_assert_not_reached(); |
| |
| case QCOW2_SUBCLUSTER_UNALLOCATED_PLAIN: |
| case QCOW2_SUBCLUSTER_UNALLOCATED_ALLOC: |
| assert(bs->backing); /* otherwise handled in qcow2_co_preadv_part */ |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO); |
| return bdrv_co_preadv_part(bs->backing, offset, bytes, |
| qiov, qiov_offset, 0); |
| |
| case QCOW2_SUBCLUSTER_COMPRESSED: |
| return qcow2_co_preadv_compressed(bs, host_offset, |
| offset, bytes, qiov, qiov_offset); |
| |
| case QCOW2_SUBCLUSTER_NORMAL: |
| if (bs->encrypted) { |
| return qcow2_co_preadv_encrypted(bs, host_offset, |
| offset, bytes, qiov, qiov_offset); |
| } |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); |
| return bdrv_co_preadv_part(s->data_file, host_offset, |
| bytes, qiov, qiov_offset, 0); |
| |
| default: |
| g_assert_not_reached(); |
| } |
| |
| g_assert_not_reached(); |
| } |
| |
| static coroutine_fn int qcow2_co_preadv_task_entry(AioTask *task) |
| { |
| Qcow2AioTask *t = container_of(task, Qcow2AioTask, task); |
| |
| assert(!t->l2meta); |
| |
| return qcow2_co_preadv_task(t->bs, t->subcluster_type, |
| t->host_offset, t->offset, t->bytes, |
| t->qiov, t->qiov_offset); |
| } |
| |
| static coroutine_fn int qcow2_co_preadv_part(BlockDriverState *bs, |
| uint64_t offset, uint64_t bytes, |
| QEMUIOVector *qiov, |
| size_t qiov_offset, int flags) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int ret = 0; |
| unsigned int cur_bytes; /* number of bytes in current iteration */ |
| uint64_t host_offset = 0; |
| QCow2SubclusterType type; |
| AioTaskPool *aio = NULL; |
| |
| while (bytes != 0 && aio_task_pool_status(aio) == 0) { |
| /* prepare next request */ |
| cur_bytes = MIN(bytes, INT_MAX); |
| if (s->crypto) { |
| cur_bytes = MIN(cur_bytes, |
| QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); |
| } |
| |
| qemu_co_mutex_lock(&s->lock); |
| ret = qcow2_get_host_offset(bs, offset, &cur_bytes, |
| &host_offset, &type); |
| qemu_co_mutex_unlock(&s->lock); |
| if (ret < 0) { |
| goto out; |
| } |
| |
| if (type == QCOW2_SUBCLUSTER_ZERO_PLAIN || |
| type == QCOW2_SUBCLUSTER_ZERO_ALLOC || |
| (type == QCOW2_SUBCLUSTER_UNALLOCATED_PLAIN && !bs->backing) || |
| (type == QCOW2_SUBCLUSTER_UNALLOCATED_ALLOC && !bs->backing)) |
| { |
| qemu_iovec_memset(qiov, qiov_offset, 0, cur_bytes); |
| } else { |
| if (!aio && cur_bytes != bytes) { |
| aio = aio_task_pool_new(QCOW2_MAX_WORKERS); |
| } |
| ret = qcow2_add_task(bs, aio, qcow2_co_preadv_task_entry, type, |
| host_offset, offset, cur_bytes, |
| qiov, qiov_offset, NULL); |
| if (ret < 0) { |
| goto out; |
| } |
| } |
| |
| bytes -= cur_bytes; |
| offset += cur_bytes; |
| qiov_offset += cur_bytes; |
| } |
| |
| out: |
| if (aio) { |
| aio_task_pool_wait_all(aio); |
| if (ret == 0) { |
| ret = aio_task_pool_status(aio); |
| } |
| g_free(aio); |
| } |
| |
| return ret; |
| } |
| |
| /* Check if it's possible to merge a write request with the writing of |
| * the data from the COW regions */ |
| static bool merge_cow(uint64_t offset, unsigned bytes, |
| QEMUIOVector *qiov, size_t qiov_offset, |
| QCowL2Meta *l2meta) |
| { |
| QCowL2Meta *m; |
| |
| for (m = l2meta; m != NULL; m = m->next) { |
| /* If both COW regions are empty then there's nothing to merge */ |
| if (m->cow_start.nb_bytes == 0 && m->cow_end.nb_bytes == 0) { |
| continue; |
| } |
| |
| /* If COW regions are handled already, skip this too */ |
| if (m->skip_cow) { |
| continue; |
| } |
| |
| /* |
| * The write request should start immediately after the first |
| * COW region. This does not always happen because the area |
| * touched by the request can be larger than the one defined |
| * by @m (a single request can span an area consisting of a |
| * mix of previously unallocated and allocated clusters, that |
| * is why @l2meta is a list). |
| */ |
| if (l2meta_cow_start(m) + m->cow_start.nb_bytes != offset) { |
| /* In this case the request starts before this region */ |
| assert(offset < l2meta_cow_start(m)); |
| assert(m->cow_start.nb_bytes == 0); |
| continue; |
| } |
| |
| /* The write request should end immediately before the second |
| * COW region (see above for why it does not always happen) */ |
| if (m->offset + m->cow_end.offset != offset + bytes) { |
| assert(offset + bytes > m->offset + m->cow_end.offset); |
| assert(m->cow_end.nb_bytes == 0); |
| continue; |
| } |
| |
| /* Make sure that adding both COW regions to the QEMUIOVector |
| * does not exceed IOV_MAX */ |
| if (qemu_iovec_subvec_niov(qiov, qiov_offset, bytes) > IOV_MAX - 2) { |
| continue; |
| } |
| |
| m->data_qiov = qiov; |
| m->data_qiov_offset = qiov_offset; |
| return true; |
| } |
| |
| return false; |
| } |
| |
| /* |
| * Return 1 if the COW regions read as zeroes, 0 if not, < 0 on error. |
| * Note that returning 0 does not guarantee non-zero data. |
| */ |
| static int is_zero_cow(BlockDriverState *bs, QCowL2Meta *m) |
| { |
| /* |
| * This check is designed for optimization shortcut so it must be |
| * efficient. |
| * Instead of is_zero(), use bdrv_co_is_zero_fast() as it is |
| * faster (but not as accurate and can result in false negatives). |
| */ |
| int ret = bdrv_co_is_zero_fast(bs, m->offset + m->cow_start.offset, |
| m->cow_start.nb_bytes); |
| if (ret <= 0) { |
| return ret; |
| } |
| |
| return bdrv_co_is_zero_fast(bs, m->offset + m->cow_end.offset, |
| m->cow_end.nb_bytes); |
| } |
| |
| static int handle_alloc_space(BlockDriverState *bs, QCowL2Meta *l2meta) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| QCowL2Meta *m; |
| |
| if (!(s->data_file->bs->supported_zero_flags & BDRV_REQ_NO_FALLBACK)) { |
| return 0; |
| } |
| |
| if (bs->encrypted) { |
| return 0; |
| } |
| |
| for (m = l2meta; m != NULL; m = m->next) { |
| int ret; |
| uint64_t start_offset = m->alloc_offset + m->cow_start.offset; |
| unsigned nb_bytes = m->cow_end.offset + m->cow_end.nb_bytes - |
| m->cow_start.offset; |
| |
| if (!m->cow_start.nb_bytes && !m->cow_end.nb_bytes) { |
| continue; |
| } |
| |
| ret = is_zero_cow(bs, m); |
| if (ret < 0) { |
| return ret; |
| } else if (ret == 0) { |
| continue; |
| } |
| |
| /* |
| * instead of writing zero COW buffers, |
| * efficiently zero out the whole clusters |
| */ |
| |
| ret = qcow2_pre_write_overlap_check(bs, 0, start_offset, nb_bytes, |
| true); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC_SPACE); |
| ret = bdrv_co_pwrite_zeroes(s->data_file, start_offset, nb_bytes, |
| BDRV_REQ_NO_FALLBACK); |
| if (ret < 0) { |
| if (ret != -ENOTSUP && ret != -EAGAIN) { |
| return ret; |
| } |
| continue; |
| } |
| |
| trace_qcow2_skip_cow(qemu_coroutine_self(), m->offset, m->nb_clusters); |
| m->skip_cow = true; |
| } |
| return 0; |
| } |
| |
| /* |
| * qcow2_co_pwritev_task |
| * Called with s->lock unlocked |
| * l2meta - if not NULL, qcow2_co_pwritev_task() will consume it. Caller must |
| * not use it somehow after qcow2_co_pwritev_task() call |
| */ |
| static coroutine_fn int qcow2_co_pwritev_task(BlockDriverState *bs, |
| uint64_t host_offset, |
| uint64_t offset, uint64_t bytes, |
| QEMUIOVector *qiov, |
| uint64_t qiov_offset, |
| QCowL2Meta *l2meta) |
| { |
| int ret; |
| BDRVQcow2State *s = bs->opaque; |
| void *crypt_buf = NULL; |
| QEMUIOVector encrypted_qiov; |
| |
| if (bs->encrypted) { |
| assert(s->crypto); |
| assert(bytes <= QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); |
| crypt_buf = qemu_try_blockalign(bs->file->bs, bytes); |
| if (crypt_buf == NULL) { |
| ret = -ENOMEM; |
| goto out_unlocked; |
| } |
| qemu_iovec_to_buf(qiov, qiov_offset, crypt_buf, bytes); |
| |
| if (qcow2_co_encrypt(bs, host_offset, offset, crypt_buf, bytes) < 0) { |
| ret = -EIO; |
| goto out_unlocked; |
| } |
| |
| qemu_iovec_init_buf(&encrypted_qiov, crypt_buf, bytes); |
| qiov = &encrypted_qiov; |
| qiov_offset = 0; |
| } |
| |
| /* Try to efficiently initialize the physical space with zeroes */ |
| ret = handle_alloc_space(bs, l2meta); |
| if (ret < 0) { |
| goto out_unlocked; |
| } |
| |
| /* |
| * If we need to do COW, check if it's possible to merge the |
| * writing of the guest data together with that of the COW regions. |
| * If it's not possible (or not necessary) then write the |
| * guest data now. |
| */ |
| if (!merge_cow(offset, bytes, qiov, qiov_offset, l2meta)) { |
| BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO); |
| trace_qcow2_writev_data(qemu_coroutine_self(), host_offset); |
| ret = bdrv_co_pwritev_part(s->data_file, host_offset, |
| bytes, qiov, qiov_offset, 0); |
| if (ret < 0) { |
| goto out_unlocked; |
| } |
| } |
| |
| qemu_co_mutex_lock(&s->lock); |
| |
| ret = qcow2_handle_l2meta(bs, &l2meta, true); |
| goto out_locked; |
| |
| out_unlocked: |
| qemu_co_mutex_lock(&s->lock); |
| |
| out_locked: |
| qcow2_handle_l2meta(bs, &l2meta, false); |
| qemu_co_mutex_unlock(&s->lock); |
| |
| qemu_vfree(crypt_buf); |
| |
| return ret; |
| } |
| |
| static coroutine_fn int qcow2_co_pwritev_task_entry(AioTask *task) |
| { |
| Qcow2AioTask *t = container_of(task, Qcow2AioTask, task); |
| |
| assert(!t->subcluster_type); |
| |
| return qcow2_co_pwritev_task(t->bs, t->host_offset, |
| t->offset, t->bytes, t->qiov, t->qiov_offset, |
| t->l2meta); |
| } |
| |
| static coroutine_fn int qcow2_co_pwritev_part( |
| BlockDriverState *bs, uint64_t offset, uint64_t bytes, |
| QEMUIOVector *qiov, size_t qiov_offset, int flags) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int offset_in_cluster; |
| int ret; |
| unsigned int cur_bytes; /* number of sectors in current iteration */ |
| uint64_t host_offset; |
| QCowL2Meta *l2meta = NULL; |
| AioTaskPool *aio = NULL; |
| |
| trace_qcow2_writev_start_req(qemu_coroutine_self(), offset, bytes); |
| |
| while (bytes != 0 && aio_task_pool_status(aio) == 0) { |
| |
| l2meta = NULL; |
| |
| trace_qcow2_writev_start_part(qemu_coroutine_self()); |
| offset_in_cluster = offset_into_cluster(s, offset); |
| cur_bytes = MIN(bytes, INT_MAX); |
| if (bs->encrypted) { |
| cur_bytes = MIN(cur_bytes, |
| QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size |
| - offset_in_cluster); |
| } |
| |
| qemu_co_mutex_lock(&s->lock); |
| |
| ret = qcow2_alloc_host_offset(bs, offset, &cur_bytes, |
| &host_offset, &l2meta); |
| if (ret < 0) { |
| goto out_locked; |
| } |
| |
| ret = qcow2_pre_write_overlap_check(bs, 0, host_offset, |
| cur_bytes, true); |
| if (ret < 0) { |
| goto out_locked; |
| } |
| |
| qemu_co_mutex_unlock(&s->lock); |
| |
| if (!aio && cur_bytes != bytes) { |
| aio = aio_task_pool_new(QCOW2_MAX_WORKERS); |
| } |
| ret = qcow2_add_task(bs, aio, qcow2_co_pwritev_task_entry, 0, |
| host_offset, offset, |
| cur_bytes, qiov, qiov_offset, l2meta); |
| l2meta = NULL; /* l2meta is consumed by qcow2_co_pwritev_task() */ |
| if (ret < 0) { |
| goto fail_nometa; |
| } |
| |
| bytes -= cur_bytes; |
| offset += cur_bytes; |
| qiov_offset += cur_bytes; |
| trace_qcow2_writev_done_part(qemu_coroutine_self(), cur_bytes); |
| } |
| ret = 0; |
| |
| qemu_co_mutex_lock(&s->lock); |
| |
| out_locked: |
| qcow2_handle_l2meta(bs, &l2meta, false); |
| |
| qemu_co_mutex_unlock(&s->lock); |
| |
| fail_nometa: |
| if (aio) { |
| aio_task_pool_wait_all(aio); |
| if (ret == 0) { |
| ret = aio_task_pool_status(aio); |
| } |
| g_free(aio); |
| } |
| |
| trace_qcow2_writev_done_req(qemu_coroutine_self(), ret); |
| |
| return ret; |
| } |
| |
| static int qcow2_inactivate(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int ret, result = 0; |
| Error *local_err = NULL; |
| |
| qcow2_store_persistent_dirty_bitmaps(bs, true, &local_err); |
| if (local_err != NULL) { |
| result = -EINVAL; |
| error_reportf_err(local_err, "Lost persistent bitmaps during " |
| "inactivation of node '%s': ", |
| bdrv_get_device_or_node_name(bs)); |
| } |
| |
| ret = qcow2_cache_flush(bs, s->l2_table_cache); |
| if (ret) { |
| result = ret; |
| error_report("Failed to flush the L2 table cache: %s", |
| strerror(-ret)); |
| } |
| |
| ret = qcow2_cache_flush(bs, s->refcount_block_cache); |
| if (ret) { |
| result = ret; |
| error_report("Failed to flush the refcount block cache: %s", |
| strerror(-ret)); |
| } |
| |
| if (result == 0) { |
| qcow2_mark_clean(bs); |
| } |
| |
| return result; |
| } |
| |
| static void qcow2_close(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| qemu_vfree(s->l1_table); |
| /* else pre-write overlap checks in cache_destroy may crash */ |
| s->l1_table = NULL; |
| |
| if (!(s->flags & BDRV_O_INACTIVE)) { |
| qcow2_inactivate(bs); |
| } |
| |
| cache_clean_timer_del(bs); |
| qcow2_cache_destroy(s->l2_table_cache); |
| qcow2_cache_destroy(s->refcount_block_cache); |
| |
| qcrypto_block_free(s->crypto); |
| s->crypto = NULL; |
| qapi_free_QCryptoBlockOpenOptions(s->crypto_opts); |
| |
| g_free(s->unknown_header_fields); |
| cleanup_unknown_header_ext(bs); |
| |
| g_free(s->image_data_file); |
| g_free(s->image_backing_file); |
| g_free(s->image_backing_format); |
| |
| if (has_data_file(bs)) { |
| bdrv_unref_child(bs, s->data_file); |
| s->data_file = NULL; |
| } |
| |
| qcow2_refcount_close(bs); |
| qcow2_free_snapshots(bs); |
| } |
| |
| static void coroutine_fn qcow2_co_invalidate_cache(BlockDriverState *bs, |
| Error **errp) |
| { |
| ERRP_GUARD(); |
| BDRVQcow2State *s = bs->opaque; |
| int flags = s->flags; |
| QCryptoBlock *crypto = NULL; |
| QDict *options; |
| int ret; |
| |
| /* |
| * Backing files are read-only which makes all of their metadata immutable, |
| * that means we don't have to worry about reopening them here. |
| */ |
| |
| crypto = s->crypto; |
| s->crypto = NULL; |
| |
| qcow2_close(bs); |
| |
| memset(s, 0, sizeof(BDRVQcow2State)); |
| options = qdict_clone_shallow(bs->options); |
| |
| flags &= ~BDRV_O_INACTIVE; |
| qemu_co_mutex_lock(&s->lock); |
| ret = qcow2_do_open(bs, options, flags, errp); |
| qemu_co_mutex_unlock(&s->lock); |
| qobject_unref(options); |
| if (ret < 0) { |
| error_prepend(errp, "Could not reopen qcow2 layer: "); |
| bs->drv = NULL; |
| return; |
| } |
| |
| s->crypto = crypto; |
| } |
| |
| static size_t header_ext_add(char *buf, uint32_t magic, const void *s, |
| size_t len, size_t buflen) |
| { |
| QCowExtension *ext_backing_fmt = (QCowExtension*) buf; |
| size_t ext_len = sizeof(QCowExtension) + ((len + 7) & ~7); |
| |
| if (buflen < ext_len) { |
| return -ENOSPC; |
| } |
| |
| *ext_backing_fmt = (QCowExtension) { |
| .magic = cpu_to_be32(magic), |
| .len = cpu_to_be32(len), |
| }; |
| |
| if (len) { |
| memcpy(buf + sizeof(QCowExtension), s, len); |
| } |
| |
| return ext_len; |
| } |
| |
| /* |
| * Updates the qcow2 header, including the variable length parts of it, i.e. |
| * the backing file name and all extensions. qcow2 was not designed to allow |
| * such changes, so if we run out of space (we can only use the first cluster) |
| * this function may fail. |
| * |
| * Returns 0 on success, -errno in error cases. |
| */ |
| int qcow2_update_header(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| QCowHeader *header; |
| char *buf; |
| size_t buflen = s->cluster_size; |
| int ret; |
| uint64_t total_size; |
| uint32_t refcount_table_clusters; |
| size_t header_length; |
| Qcow2UnknownHeaderExtension *uext; |
| |
| buf = qemu_blockalign(bs, buflen); |
| |
| /* Header structure */ |
| header = (QCowHeader*) buf; |
| |
| if (buflen < sizeof(*header)) { |
| ret = -ENOSPC; |
| goto fail; |
| } |
| |
| header_length = sizeof(*header) + s->unknown_header_fields_size; |
| total_size = bs->total_sectors * BDRV_SECTOR_SIZE; |
| refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3); |
| |
| ret = validate_compression_type(s, NULL); |
| if (ret) { |
| goto fail; |
| } |
| |
| *header = (QCowHeader) { |
| /* Version 2 fields */ |
| .magic = cpu_to_be32(QCOW_MAGIC), |
| .version = cpu_to_be32(s->qcow_version), |
| .backing_file_offset = 0, |
| .backing_file_size = 0, |
| .cluster_bits = cpu_to_be32(s->cluster_bits), |
| .size = cpu_to_be64(total_size), |
| .crypt_method = cpu_to_be32(s->crypt_method_header), |
| .l1_size = cpu_to_be32(s->l1_size), |
| .l1_table_offset = cpu_to_be64(s->l1_table_offset), |
| .refcount_table_offset = cpu_to_be64(s->refcount_table_offset), |
| .refcount_table_clusters = cpu_to_be32(refcount_table_clusters), |
| .nb_snapshots = cpu_to_be32(s->nb_snapshots), |
| .snapshots_offset = cpu_to_be64(s->snapshots_offset), |
| |
| /* Version 3 fields */ |
| .incompatible_features = cpu_to_be64(s->incompatible_features), |
| .compatible_features = cpu_to_be64(s->compatible_features), |
| .autoclear_features = cpu_to_be64(s->autoclear_features), |
| .refcount_order = cpu_to_be32(s->refcount_order), |
| .header_length = cpu_to_be32(header_length), |
| .compression_type = s->compression_type, |
| }; |
| |
| /* For older versions, write a shorter header */ |
| switch (s->qcow_version) { |
| case 2: |
| ret = offsetof(QCowHeader, incompatible_features); |
| break; |
| case 3: |
| ret = sizeof(*header); |
| break; |
| default: |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| buf += ret; |
| buflen -= ret; |
| memset(buf, 0, buflen); |
| |
| /* Preserve any unknown field in the header */ |
| if (s->unknown_header_fields_size) { |
| if (buflen < s->unknown_header_fields_size) { |
| ret = -ENOSPC; |
| goto fail; |
| } |
| |
| memcpy(buf, s->unknown_header_fields, s->unknown_header_fields_size); |
| buf += s->unknown_header_fields_size; |
| buflen -= s->unknown_header_fields_size; |
| } |
| |
| /* Backing file format header extension */ |
| if (s->image_backing_format) { |
| ret = header_ext_add(buf, QCOW2_EXT_MAGIC_BACKING_FORMAT, |
| s->image_backing_format, |
| strlen(s->image_backing_format), |
| buflen); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| buf += ret; |
| buflen -= ret; |
| } |
| |
| /* External data file header extension */ |
| if (has_data_file(bs) && s->image_data_file) { |
| ret = header_ext_add(buf, QCOW2_EXT_MAGIC_DATA_FILE, |
| s->image_data_file, strlen(s->image_data_file), |
| buflen); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| buf += ret; |
| buflen -= ret; |
| } |
| |
| /* Full disk encryption header pointer extension */ |
| if (s->crypto_header.offset != 0) { |
| s->crypto_header.offset = cpu_to_be64(s->crypto_header.offset); |
| s->crypto_header.length = cpu_to_be64(s->crypto_header.length); |
| ret = header_ext_add(buf, QCOW2_EXT_MAGIC_CRYPTO_HEADER, |
| &s->crypto_header, sizeof(s->crypto_header), |
| buflen); |
| s->crypto_header.offset = be64_to_cpu(s->crypto_header.offset); |
| s->crypto_header.length = be64_to_cpu(s->crypto_header.length); |
| if (ret < 0) { |
| goto fail; |
| } |
| buf += ret; |
| buflen -= ret; |
| } |
| |
| /* |
| * Feature table. A mere 8 feature names occupies 392 bytes, and |
| * when coupled with the v3 minimum header of 104 bytes plus the |
| * 8-byte end-of-extension marker, that would leave only 8 bytes |
| * for a backing file name in an image with 512-byte clusters. |
| * Thus, we choose to omit this header for cluster sizes 4k and |
| * smaller. |
| */ |
| if (s->qcow_version >= 3 && s->cluster_size > 4096) { |
| static const Qcow2Feature features[] = { |
| { |
| .type = QCOW2_FEAT_TYPE_INCOMPATIBLE, |
| .bit = QCOW2_INCOMPAT_DIRTY_BITNR, |
| .name = "dirty bit", |
| }, |
| { |
| .type = QCOW2_FEAT_TYPE_INCOMPATIBLE, |
| .bit = QCOW2_INCOMPAT_CORRUPT_BITNR, |
| .name = "corrupt bit", |
| }, |
| { |
| .type = QCOW2_FEAT_TYPE_INCOMPATIBLE, |
| .bit = QCOW2_INCOMPAT_DATA_FILE_BITNR, |
| .name = "external data file", |
| }, |
| { |
| .type = QCOW2_FEAT_TYPE_INCOMPATIBLE, |
| .bit = QCOW2_INCOMPAT_COMPRESSION_BITNR, |
| .name = "compression type", |
| }, |
| { |
| .type = QCOW2_FEAT_TYPE_INCOMPATIBLE, |
| .bit = QCOW2_INCOMPAT_EXTL2_BITNR, |
| .name = "extended L2 entries", |
| }, |
| { |
| .type = QCOW2_FEAT_TYPE_COMPATIBLE, |
| .bit = QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR, |
| .name = "lazy refcounts", |
| }, |
| { |
| .type = QCOW2_FEAT_TYPE_AUTOCLEAR, |
| .bit = QCOW2_AUTOCLEAR_BITMAPS_BITNR, |
| .name = "bitmaps", |
| }, |
| { |
| .type = QCOW2_FEAT_TYPE_AUTOCLEAR, |
| .bit = QCOW2_AUTOCLEAR_DATA_FILE_RAW_BITNR, |
| .name = "raw external data", |
| }, |
| }; |
| |
| ret = header_ext_add(buf, QCOW2_EXT_MAGIC_FEATURE_TABLE, |
| features, sizeof(features), buflen); |
| if (ret < 0) { |
| goto fail; |
| } |
| buf += ret; |
| buflen -= ret; |
| } |
| |
| /* Bitmap extension */ |
| if (s->nb_bitmaps > 0) { |
| Qcow2BitmapHeaderExt bitmaps_header = { |
| .nb_bitmaps = cpu_to_be32(s->nb_bitmaps), |
| .bitmap_directory_size = |
| cpu_to_be64(s->bitmap_directory_size), |
| .bitmap_directory_offset = |
| cpu_to_be64(s->bitmap_directory_offset) |
| }; |
| ret = header_ext_add(buf, QCOW2_EXT_MAGIC_BITMAPS, |
| &bitmaps_header, sizeof(bitmaps_header), |
| buflen); |
| if (ret < 0) { |
| goto fail; |
| } |
| buf += ret; |
| buflen -= ret; |
| } |
| |
| /* Keep unknown header extensions */ |
| QLIST_FOREACH(uext, &s->unknown_header_ext, next) { |
| ret = header_ext_add(buf, uext->magic, uext->data, uext->len, buflen); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| buf += ret; |
| buflen -= ret; |
| } |
| |
| /* End of header extensions */ |
| ret = header_ext_add(buf, QCOW2_EXT_MAGIC_END, NULL, 0, buflen); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| buf += ret; |
| buflen -= ret; |
| |
| /* Backing file name */ |
| if (s->image_backing_file) { |
| size_t backing_file_len = strlen(s->image_backing_file); |
| |
| if (buflen < backing_file_len) { |
| ret = -ENOSPC; |
| goto fail; |
| } |
| |
| /* Using strncpy is ok here, since buf is not NUL-terminated. */ |
| strncpy(buf, s->image_backing_file, buflen); |
| |
| header->backing_file_offset = cpu_to_be64(buf - ((char*) header)); |
| header->backing_file_size = cpu_to_be32(backing_file_len); |
| } |
| |
| /* Write the new header */ |
| ret = bdrv_pwrite(bs->file, 0, header, s->cluster_size); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = 0; |
| fail: |
| qemu_vfree(header); |
| return ret; |
| } |
| |
| static int qcow2_change_backing_file(BlockDriverState *bs, |
| const char *backing_file, const char *backing_fmt) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| |
| /* Adding a backing file means that the external data file alone won't be |
| * enough to make sense of the content */ |
| if (backing_file && data_file_is_raw(bs)) { |
| return -EINVAL; |
| } |
| |
| if (backing_file && strlen(backing_file) > 1023) { |
| return -EINVAL; |
| } |
| |
| pstrcpy(bs->auto_backing_file, sizeof(bs->auto_backing_file), |
| backing_file ?: ""); |
| pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: ""); |
| pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: ""); |
| |
| g_free(s->image_backing_file); |
| g_free(s->image_backing_format); |
| |
| s->image_backing_file = backing_file ? g_strdup(bs->backing_file) : NULL; |
| s->image_backing_format = backing_fmt ? g_strdup(bs->backing_format) : NULL; |
| |
| return qcow2_update_header(bs); |
| } |
| |
| static int qcow2_set_up_encryption(BlockDriverState *bs, |
| QCryptoBlockCreateOptions *cryptoopts, |
| Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| QCryptoBlock *crypto = NULL; |
| int fmt, ret; |
| |
| switch (cryptoopts->format) { |
| case Q_CRYPTO_BLOCK_FORMAT_LUKS: |
| fmt = QCOW_CRYPT_LUKS; |
| break; |
| case Q_CRYPTO_BLOCK_FORMAT_QCOW: |
| fmt = QCOW_CRYPT_AES; |
| break; |
| default: |
| error_setg(errp, "Crypto format not supported in qcow2"); |
| return -EINVAL; |
| } |
| |
| s->crypt_method_header = fmt; |
| |
| crypto = qcrypto_block_create(cryptoopts, "encrypt.", |
| qcow2_crypto_hdr_init_func, |
| qcow2_crypto_hdr_write_func, |
| bs, errp); |
| if (!crypto) { |
| return -EINVAL; |
| } |
| |
| ret = qcow2_update_header(bs); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not write encryption header"); |
| goto out; |
| } |
| |
| ret = 0; |
| out: |
| qcrypto_block_free(crypto); |
| return ret; |
| } |
| |
| /** |
| * Preallocates metadata structures for data clusters between @offset (in the |
| * guest disk) and @new_length (which is thus generally the new guest disk |
| * size). |
| * |
| * Returns: 0 on success, -errno on failure. |
| */ |
| static int coroutine_fn preallocate_co(BlockDriverState *bs, uint64_t offset, |
| uint64_t new_length, PreallocMode mode, |
| Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| uint64_t bytes; |
| uint64_t host_offset = 0; |
| int64_t file_length; |
| unsigned int cur_bytes; |
| int ret; |
| QCowL2Meta *meta = NULL, *m; |
| |
| assert(offset <= new_length); |
| bytes = new_length - offset; |
| |
| while (bytes) { |
| cur_bytes = MIN(bytes, QEMU_ALIGN_DOWN(INT_MAX, s->cluster_size)); |
| ret = qcow2_alloc_host_offset(bs, offset, &cur_bytes, |
| &host_offset, &meta); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Allocating clusters failed"); |
| goto out; |
| } |
| |
| for (m = meta; m != NULL; m = m->next) { |
| m->prealloc = true; |
| } |
| |
| ret = qcow2_handle_l2meta(bs, &meta, true); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Mapping clusters failed"); |
| goto out; |
| } |
| |
| /* TODO Preallocate data if requested */ |
| |
| bytes -= cur_bytes; |
| offset += cur_bytes; |
| } |
| |
| /* |
| * It is expected that the image file is large enough to actually contain |
| * all of the allocated clusters (otherwise we get failing reads after |
| * EOF). Extend the image to the last allocated sector. |
| */ |
| file_length = bdrv_getlength(s->data_file->bs); |
| if (file_length < 0) { |
| error_setg_errno(errp, -file_length, "Could not get file size"); |
| ret = file_length; |
| goto out; |
| } |
| |
| if (host_offset + cur_bytes > file_length) { |
| if (mode == PREALLOC_MODE_METADATA) { |
| mode = PREALLOC_MODE_OFF; |
| } |
| ret = bdrv_co_truncate(s->data_file, host_offset + cur_bytes, false, |
| mode, 0, errp); |
| if (ret < 0) { |
| goto out; |
| } |
| } |
| |
| ret = 0; |
| |
| out: |
| qcow2_handle_l2meta(bs, &meta, false); |
| return ret; |
| } |
| |
| /* qcow2_refcount_metadata_size: |
| * @clusters: number of clusters to refcount (including data and L1/L2 tables) |
| * @cluster_size: size of a cluster, in bytes |
| * @refcount_order: refcount bits power-of-2 exponent |
| * @generous_increase: allow for the refcount table to be 1.5x as large as it |
| * needs to be |
| * |
| * Returns: Number of bytes required for refcount blocks and table metadata. |
| */ |
| int64_t qcow2_refcount_metadata_size(int64_t clusters, size_t cluster_size, |
| int refcount_order, bool generous_increase, |
| uint64_t *refblock_count) |
| { |
| /* |
| * Every host cluster is reference-counted, including metadata (even |
| * refcount metadata is recursively included). |
| * |
| * An accurate formula for the size of refcount metadata size is difficult |
| * to derive. An easier method of calculation is finding the fixed point |
| * where no further refcount blocks or table clusters are required to |
| * reference count every cluster. |
| */ |
| int64_t blocks_per_table_cluster = cluster_size / REFTABLE_ENTRY_SIZE; |
| int64_t refcounts_per_block = cluster_size * 8 / (1 << refcount_order); |
| int64_t table = 0; /* number of refcount table clusters */ |
| int64_t blocks = 0; /* number of refcount block clusters */ |
| int64_t last; |
| int64_t n = 0; |
| |
| do { |
| last = n; |
| blocks = DIV_ROUND_UP(clusters + table + blocks, refcounts_per_block); |
| table = DIV_ROUND_UP(blocks, blocks_per_table_cluster); |
| n = clusters + blocks + table; |
| |
| if (n == last && generous_increase) { |
| clusters += DIV_ROUND_UP(table, 2); |
| n = 0; /* force another loop */ |
| generous_increase = false; |
| } |
| } while (n != last); |
| |
| if (refblock_count) { |
| *refblock_count = blocks; |
| } |
| |
| return (blocks + table) * cluster_size; |
| } |
| |
| /** |
| * qcow2_calc_prealloc_size: |
| * @total_size: virtual disk size in bytes |
| * @cluster_size: cluster size in bytes |
| * @refcount_order: refcount bits power-of-2 exponent |
| * @extended_l2: true if the image has extended L2 entries |
| * |
| * Returns: Total number of bytes required for the fully allocated image |
| * (including metadata). |
| */ |
| static int64_t qcow2_calc_prealloc_size(int64_t total_size, |
| size_t cluster_size, |
| int refcount_order, |
| bool extended_l2) |
| { |
| int64_t meta_size = 0; |
| uint64_t nl1e, nl2e; |
| int64_t aligned_total_size = ROUND_UP(total_size, cluster_size); |
| size_t l2e_size = extended_l2 ? L2E_SIZE_EXTENDED : L2E_SIZE_NORMAL; |
| |
| /* header: 1 cluster */ |
| meta_size += cluster_size; |
| |
| /* total size of L2 tables */ |
| nl2e = aligned_total_size / cluster_size; |
| nl2e = ROUND_UP(nl2e, cluster_size / l2e_size); |
| meta_size += nl2e * l2e_size; |
| |
| /* total size of L1 tables */ |
| nl1e = nl2e * l2e_size / cluster_size; |
| nl1e = ROUND_UP(nl1e, cluster_size / L1E_SIZE); |
| meta_size += nl1e * L1E_SIZE; |
| |
| /* total size of refcount table and blocks */ |
| meta_size += qcow2_refcount_metadata_size( |
| (meta_size + aligned_total_size) / cluster_size, |
| cluster_size, refcount_order, false, NULL); |
| |
| return meta_size + aligned_total_size; |
| } |
| |
| static bool validate_cluster_size(size_t cluster_size, bool extended_l2, |
| Error **errp) |
| { |
| int cluster_bits = ctz32(cluster_size); |
| if (cluster_bits < MIN_CLUSTER_BITS || cluster_bits > MAX_CLUSTER_BITS || |
| (1 << cluster_bits) != cluster_size) |
| { |
| error_setg(errp, "Cluster size must be a power of two between %d and " |
| "%dk", 1 << MIN_CLUSTER_BITS, 1 << (MAX_CLUSTER_BITS - 10)); |
| return false; |
| } |
| |
| if (extended_l2) { |
| unsigned min_cluster_size = |
| (1 << MIN_CLUSTER_BITS) * QCOW_EXTL2_SUBCLUSTERS_PER_CLUSTER; |
| if (cluster_size < min_cluster_size) { |
| error_setg(errp, "Extended L2 entries are only supported with " |
| "cluster sizes of at least %u bytes", min_cluster_size); |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| static size_t qcow2_opt_get_cluster_size_del(QemuOpts *opts, bool extended_l2, |
| Error **errp) |
| { |
| size_t cluster_size; |
| |
| cluster_size = qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE, |
| DEFAULT_CLUSTER_SIZE); |
| if (!validate_cluster_size(cluster_size, extended_l2, errp)) { |
| return 0; |
| } |
| return cluster_size; |
| } |
| |
| static int qcow2_opt_get_version_del(QemuOpts *opts, Error **errp) |
| { |
| char *buf; |
| int ret; |
| |
| buf = qemu_opt_get_del(opts, BLOCK_OPT_COMPAT_LEVEL); |
| if (!buf) { |
| ret = 3; /* default */ |
| } else if (!strcmp(buf, "0.10")) { |
| ret = 2; |
| } else if (!strcmp(buf, "1.1")) { |
| ret = 3; |
| } else { |
| error_setg(errp, "Invalid compatibility level: '%s'", buf); |
| ret = -EINVAL; |
| } |
| g_free(buf); |
| return ret; |
| } |
| |
| static uint64_t qcow2_opt_get_refcount_bits_del(QemuOpts *opts, int version, |
| Error **errp) |
| { |
| uint64_t refcount_bits; |
| |
| refcount_bits = qemu_opt_get_number_del(opts, BLOCK_OPT_REFCOUNT_BITS, 16); |
| if (refcount_bits > 64 || !is_power_of_2(refcount_bits)) { |
| error_setg(errp, "Refcount width must be a power of two and may not " |
| "exceed 64 bits"); |
| return 0; |
| } |
| |
| if (version < 3 && refcount_bits != 16) { |
| error_setg(errp, "Different refcount widths than 16 bits require " |
| "compatibility level 1.1 or above (use compat=1.1 or " |
| "greater)"); |
| return 0; |
| } |
| |
| return refcount_bits; |
| } |
| |
| static int coroutine_fn |
| qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp) |
| { |
| BlockdevCreateOptionsQcow2 *qcow2_opts; |
| QDict *options; |
| |
| /* |
| * Open the image file and write a minimal qcow2 header. |
| * |
| * We keep things simple and start with a zero-sized image. We also |
| * do without refcount blocks or a L1 table for now. We'll fix the |
| * inconsistency later. |
| * |
| * We do need a refcount table because growing the refcount table means |
| * allocating two new refcount blocks - the second of which would be at |
| * 2 GB for 64k clusters, and we don't want to have a 2 GB initial file |
| * size for any qcow2 image. |
| */ |
| BlockBackend *blk = NULL; |
| BlockDriverState *bs = NULL; |
| BlockDriverState *data_bs = NULL; |
| QCowHeader *header; |
| size_t cluster_size; |
| int version; |
| int refcount_order; |
| uint64_t *refcount_table; |
| int ret; |
| uint8_t compression_type = QCOW2_COMPRESSION_TYPE_ZLIB; |
| |
| assert(create_options->driver == BLOCKDEV_DRIVER_QCOW2); |
| qcow2_opts = &create_options->u.qcow2; |
| |
| bs = bdrv_open_blockdev_ref(qcow2_opts->file, errp); |
| if (bs == NULL) { |
| return -EIO; |
| } |
| |
| /* Validate options and set default values */ |
| if (!QEMU_IS_ALIGNED(qcow2_opts->size, BDRV_SECTOR_SIZE)) { |
| error_setg(errp, "Image size must be a multiple of %u bytes", |
| (unsigned) BDRV_SECTOR_SIZE); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| if (qcow2_opts->has_version) { |
| switch (qcow2_opts->version) { |
| case BLOCKDEV_QCOW2_VERSION_V2: |
| version = 2; |
| break; |
| case BLOCKDEV_QCOW2_VERSION_V3: |
| version = 3; |
| break; |
| default: |
| g_assert_not_reached(); |
| } |
| } else { |
| version = 3; |
| } |
| |
| if (qcow2_opts->has_cluster_size) { |
| cluster_size = qcow2_opts->cluster_size; |
| } else { |
| cluster_size = DEFAULT_CLUSTER_SIZE; |
| } |
| |
| if (!qcow2_opts->has_extended_l2) { |
| qcow2_opts->extended_l2 = false; |
| } |
| if (qcow2_opts->extended_l2) { |
| if (version < 3) { |
| error_setg(errp, "Extended L2 entries are only supported with " |
| "compatibility level 1.1 and above (use version=v3 or " |
| "greater)"); |
| ret = -EINVAL; |
| goto out; |
| } |
| } |
| |
| if (!validate_cluster_size(cluster_size, qcow2_opts->extended_l2, errp)) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| if (!qcow2_opts->has_preallocation) { |
| qcow2_opts->preallocation = PREALLOC_MODE_OFF; |
| } |
| if (qcow2_opts->has_backing_file && |
| qcow2_opts->preallocation != PREALLOC_MODE_OFF && |
| !qcow2_opts->extended_l2) |
| { |
| error_setg(errp, "Backing file and preallocation can only be used at " |
| "the same time if extended_l2 is on"); |
| ret = -EINVAL; |
| goto out; |
| } |
| if (qcow2_opts->has_backing_fmt && !qcow2_opts->has_backing_file) { |
| error_setg(errp, "Backing format cannot be used without backing file"); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| if (!qcow2_opts->has_lazy_refcounts) { |
| qcow2_opts->lazy_refcounts = false; |
| } |
| if (version < 3 && qcow2_opts->lazy_refcounts) { |
| error_setg(errp, "Lazy refcounts only supported with compatibility " |
| "level 1.1 and above (use version=v3 or greater)"); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| if (!qcow2_opts->has_refcount_bits) { |
| qcow2_opts->refcount_bits = 16; |
| } |
| if (qcow2_opts->refcount_bits > 64 || |
| !is_power_of_2(qcow2_opts->refcount_bits)) |
| { |
| error_setg(errp, "Refcount width must be a power of two and may not " |
| "exceed 64 bits"); |
| ret = -EINVAL; |
| goto out; |
| } |
| if (version < 3 && qcow2_opts->refcount_bits != 16) { |
| error_setg(errp, "Different refcount widths than 16 bits require " |
| "compatibility level 1.1 or above (use version=v3 or " |
| "greater)"); |
| ret = -EINVAL; |
| goto out; |
| } |
| refcount_order = ctz32(qcow2_opts->refcount_bits); |
| |
| if (qcow2_opts->data_file_raw && !qcow2_opts->data_file) { |
| error_setg(errp, "data-file-raw requires data-file"); |
| ret = -EINVAL; |
| goto out; |
| } |
| if (qcow2_opts->data_file_raw && qcow2_opts->has_backing_file) { |
| error_setg(errp, "Backing file and data-file-raw cannot be used at " |
| "the same time"); |
| ret = -EINVAL; |
| goto out; |
| } |
| if (qcow2_opts->data_file_raw && |
| qcow2_opts->preallocation == PREALLOC_MODE_OFF) |
| { |
| /* |
| * data-file-raw means that "the external data file can be |
| * read as a consistent standalone raw image without looking |
| * at the qcow2 metadata." It does not say that the metadata |
| * must be ignored, though (and the qcow2 driver in fact does |
| * not ignore it), so the L1/L2 tables must be present and |
| * give a 1:1 mapping, so you get the same result regardless |
| * of whether you look at the metadata or whether you ignore |
| * it. |
| */ |
| qcow2_opts->preallocation = PREALLOC_MODE_METADATA; |
| |
| /* |
| * Cannot use preallocation with backing files, but giving a |
| * backing file when specifying data_file_raw is an error |
| * anyway. |
| */ |
| assert(!qcow2_opts->has_backing_file); |
| } |
| |
| if (qcow2_opts->data_file) { |
| if (version < 3) { |
| error_setg(errp, "External data files are only supported with " |
| "compatibility level 1.1 and above (use version=v3 or " |
| "greater)"); |
| ret = -EINVAL; |
| goto out; |
| } |
| data_bs = bdrv_open_blockdev_ref(qcow2_opts->data_file, errp); |
| if (data_bs == NULL) { |
| ret = -EIO; |
| goto out; |
| } |
| } |
| |
| if (qcow2_opts->has_compression_type && |
| qcow2_opts->compression_type != QCOW2_COMPRESSION_TYPE_ZLIB) { |
| |
| ret = -EINVAL; |
| |
| if (version < 3) { |
| error_setg(errp, "Non-zlib compression type is only supported with " |
| "compatibility level 1.1 and above (use version=v3 or " |
| "greater)"); |
| goto out; |
| } |
| |
| switch (qcow2_opts->compression_type) { |
| #ifdef CONFIG_ZSTD |
| case QCOW2_COMPRESSION_TYPE_ZSTD: |
| break; |
| #endif |
| default: |
| error_setg(errp, "Unknown compression type"); |
| goto out; |
| } |
| |
| compression_type = qcow2_opts->compression_type; |
| } |
| |
| /* Create BlockBackend to write to the image */ |
| blk = blk_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL, |
| errp); |
| if (!blk) { |
| ret = -EPERM; |
| goto out; |
| } |
| blk_set_allow_write_beyond_eof(blk, true); |
| |
| /* Write the header */ |
| QEMU_BUILD_BUG_ON((1 << MIN_CLUSTER_BITS) < sizeof(*header)); |
| header = g_malloc0(cluster_size); |
| *header = (QCowHeader) { |
| .magic = cpu_to_be32(QCOW_MAGIC), |
| .version = cpu_to_be32(version), |
| .cluster_bits = cpu_to_be32(ctz32(cluster_size)), |
| .size = cpu_to_be64(0), |
| .l1_table_offset = cpu_to_be64(0), |
| .l1_size = cpu_to_be32(0), |
| .refcount_table_offset = cpu_to_be64(cluster_size), |
| .refcount_table_clusters = cpu_to_be32(1), |
| .refcount_order = cpu_to_be32(refcount_order), |
| /* don't deal with endianness since compression_type is 1 byte long */ |
| .compression_type = compression_type, |
| .header_length = cpu_to_be32(sizeof(*header)), |
| }; |
| |
| /* We'll update this to correct value later */ |
| header->crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); |
| |
| if (qcow2_opts->lazy_refcounts) { |
| header->compatible_features |= |
| cpu_to_be64(QCOW2_COMPAT_LAZY_REFCOUNTS); |
| } |
| if (data_bs) { |
| header->incompatible_features |= |
| cpu_to_be64(QCOW2_INCOMPAT_DATA_FILE); |
| } |
| if (qcow2_opts->data_file_raw) { |
| header->autoclear_features |= |
| cpu_to_be64(QCOW2_AUTOCLEAR_DATA_FILE_RAW); |
| } |
| if (compression_type != QCOW2_COMPRESSION_TYPE_ZLIB) { |
| header->incompatible_features |= |
| cpu_to_be64(QCOW2_INCOMPAT_COMPRESSION); |
| } |
| |
| if (qcow2_opts->extended_l2) { |
| header->incompatible_features |= |
| cpu_to_be64(QCOW2_INCOMPAT_EXTL2); |
| } |
| |
| ret = blk_pwrite(blk, 0, header, cluster_size, 0); |
| g_free(header); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not write qcow2 header"); |
| goto out; |
| } |
| |
| /* Write a refcount table with one refcount block */ |
| refcount_table = g_malloc0(2 * cluster_size); |
| refcount_table[0] = cpu_to_be64(2 * cluster_size); |
| ret = blk_pwrite(blk, cluster_size, refcount_table, 2 * cluster_size, 0); |
| g_free(refcount_table); |
| |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not write refcount table"); |
| goto out; |
| } |
| |
| blk_unref(blk); |
| blk = NULL; |
| |
| /* |
| * And now open the image and make it consistent first (i.e. increase the |
| * refcount of the cluster that is occupied by the header and the refcount |
| * table) |
| */ |
| options = qdict_new(); |
| qdict_put_str(options, "driver", "qcow2"); |
| qdict_put_str(options, "file", bs->node_name); |
| if (data_bs) { |
| qdict_put_str(options, "data-file", data_bs->node_name); |
| } |
| blk = blk_new_open(NULL, NULL, options, |
| BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_NO_FLUSH, |
| errp); |
| if (blk == NULL) { |
| ret = -EIO; |
| goto out; |
| } |
| |
| ret = qcow2_alloc_clusters(blk_bs(blk), 3 * cluster_size); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not allocate clusters for qcow2 " |
| "header and refcount table"); |
| goto out; |
| |
| } else if (ret != 0) { |
| error_report("Huh, first cluster in empty image is already in use?"); |
| abort(); |
| } |
| |
| /* Set the external data file if necessary */ |
| if (data_bs) { |
| BDRVQcow2State *s = blk_bs(blk)->opaque; |
| s->image_data_file = g_strdup(data_bs->filename); |
| } |
| |
| /* Create a full header (including things like feature table) */ |
| ret = qcow2_update_header(blk_bs(blk)); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not update qcow2 header"); |
| goto out; |
| } |
| |
| /* Okay, now that we have a valid image, let's give it the right size */ |
| ret = blk_truncate(blk, qcow2_opts->size, false, qcow2_opts->preallocation, |
| 0, errp); |
| if (ret < 0) { |
| error_prepend(errp, "Could not resize image: "); |
| goto out; |
| } |
| |
| /* Want a backing file? There you go. */ |
| if (qcow2_opts->has_backing_file) { |
| const char *backing_format = NULL; |
| |
| if (qcow2_opts->has_backing_fmt) { |
| backing_format = BlockdevDriver_str(qcow2_opts->backing_fmt); |
| } |
| |
| ret = bdrv_change_backing_file(blk_bs(blk), qcow2_opts->backing_file, |
| backing_format, false); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Could not assign backing file '%s' " |
| "with format '%s'", qcow2_opts->backing_file, |
| backing_format); |
| goto out; |
| } |
| } |
| |
| /* Want encryption? There you go. */ |
| if (qcow2_opts->has_encrypt) { |
| ret = qcow2_set_up_encryption(blk_bs(blk), qcow2_opts->encrypt, errp); |
| if (ret < 0) { |
| goto out; |
| } |
| } |
| |
| blk_unref(blk); |
| blk = NULL; |
| |
| /* Reopen the image without BDRV_O_NO_FLUSH to flush it before returning. |
| * Using BDRV_O_NO_IO, since encryption is now setup we don't want to |
| * have to setup decryption context. We're not doing any I/O on the top |
| * level BlockDriverState, only lower layers, where BDRV_O_NO_IO does |
| * not have effect. |
| */ |
| options = qdict_new(); |
| qdict_put_str(options, "driver", "qcow2"); |
| qdict_put_str(options, "file", bs->node_name); |
| if (data_bs) { |
| qdict_put_str(options, "data-file", data_bs->node_name); |
| } |
| blk = blk_new_open(NULL, NULL, options, |
| BDRV_O_RDWR | BDRV_O_NO_BACKING | BDRV_O_NO_IO, |
| errp); |
| if (blk == NULL) { |
| ret = -EIO; |
| goto out; |
| } |
| |
| ret = 0; |
| out: |
| blk_unref(blk); |
| bdrv_unref(bs); |
| bdrv_unref(data_bs); |
| return ret; |
| } |
| |
| static int coroutine_fn qcow2_co_create_opts(BlockDriver *drv, |
| const char *filename, |
| QemuOpts *opts, |
| Error **errp) |
| { |
| BlockdevCreateOptions *create_options = NULL; |
| QDict *qdict; |
| Visitor *v; |
| BlockDriverState *bs = NULL; |
| BlockDriverState *data_bs = NULL; |
| const char *val; |
| int ret; |
| |
| /* Only the keyval visitor supports the dotted syntax needed for |
| * encryption, so go through a QDict before getting a QAPI type. Ignore |
| * options meant for the protocol layer so that the visitor doesn't |
| * complain. */ |
| qdict = qemu_opts_to_qdict_filtered(opts, NULL, bdrv_qcow2.create_opts, |
| true); |
| |
| /* Handle encryption options */ |
| val = qdict_get_try_str(qdict, BLOCK_OPT_ENCRYPT); |
| if (val && !strcmp(val, "on")) { |
| qdict_put_str(qdict, BLOCK_OPT_ENCRYPT, "qcow"); |
| } else if (val && !strcmp(val, "off")) { |
| qdict_del(qdict, BLOCK_OPT_ENCRYPT); |
| } |
| |
| val = qdict_get_try_str(qdict, BLOCK_OPT_ENCRYPT_FORMAT); |
| if (val && !strcmp(val, "aes")) { |
| qdict_put_str(qdict, BLOCK_OPT_ENCRYPT_FORMAT, "qcow"); |
| } |
| |
| /* Convert compat=0.10/1.1 into compat=v2/v3, to be renamed into |
| * version=v2/v3 below. */ |
| val = qdict_get_try_str(qdict, BLOCK_OPT_COMPAT_LEVEL); |
| if (val && !strcmp(val, "0.10")) { |
| qdict_put_str(qdict, BLOCK_OPT_COMPAT_LEVEL, "v2"); |
| } else if (val && !strcmp(val, "1.1")) { |
| qdict_put_str(qdict, BLOCK_OPT_COMPAT_LEVEL, "v3"); |
| } |
| |
| /* Change legacy command line options into QMP ones */ |
| static const QDictRenames opt_renames[] = { |
| { BLOCK_OPT_BACKING_FILE, "backing-file" }, |
| { BLOCK_OPT_BACKING_FMT, "backing-fmt" }, |
| { BLOCK_OPT_CLUSTER_SIZE, "cluster-size" }, |
| { BLOCK_OPT_LAZY_REFCOUNTS, "lazy-refcounts" }, |
| { BLOCK_OPT_EXTL2, "extended-l2" }, |
| { BLOCK_OPT_REFCOUNT_BITS, "refcount-bits" }, |
| { BLOCK_OPT_ENCRYPT, BLOCK_OPT_ENCRYPT_FORMAT }, |
| { BLOCK_OPT_COMPAT_LEVEL, "version" }, |
| { BLOCK_OPT_DATA_FILE_RAW, "data-file-raw" }, |
| { BLOCK_OPT_COMPRESSION_TYPE, "compression-type" }, |
| { NULL, NULL }, |
| }; |
| |
| if (!qdict_rename_keys(qdict, opt_renames, errp)) { |
| ret = -EINVAL; |
| goto finish; |
| } |
| |
| /* Create and open the file (protocol layer) */ |
| ret = bdrv_create_file(filename, opts, errp); |
| if (ret < 0) { |
| goto finish; |
| } |
| |
| bs = bdrv_open(filename, NULL, NULL, |
| BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, errp); |
| if (bs == NULL) { |
| ret = -EIO; |
| goto finish; |
| } |
| |
| /* Create and open an external data file (protocol layer) */ |
| val = qdict_get_try_str(qdict, BLOCK_OPT_DATA_FILE); |
| if (val) { |
| ret = bdrv_create_file(val, opts, errp); |
| if (ret < 0) { |
| goto finish; |
| } |
| |
| data_bs = bdrv_open(val, NULL, NULL, |
| BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, |
| errp); |
| if (data_bs == NULL) { |
| ret = -EIO; |
| goto finish; |
| } |
| |
| qdict_del(qdict, BLOCK_OPT_DATA_FILE); |
| qdict_put_str(qdict, "data-file", data_bs->node_name); |
| } |
| |
| /* Set 'driver' and 'node' options */ |
| qdict_put_str(qdict, "driver", "qcow2"); |
| qdict_put_str(qdict, "file", bs->node_name); |
| |
| /* Now get the QAPI type BlockdevCreateOptions */ |
| v = qobject_input_visitor_new_flat_confused(qdict, errp); |
| if (!v) { |
| ret = -EINVAL; |
| goto finish; |
| } |
| |
| visit_type_BlockdevCreateOptions(v, NULL, &create_options, errp); |
| visit_free(v); |
| if (!create_options) { |
| ret = -EINVAL; |
| goto finish; |
| } |
| |
| /* Silently round up size */ |
| create_options->u.qcow2.size = ROUND_UP(create_options->u.qcow2.size, |
| BDRV_SECTOR_SIZE); |
| |
| /* Create the qcow2 image (format layer) */ |
| ret = qcow2_co_create(create_options, errp); |
| finish: |
| if (ret < 0) { |
| bdrv_co_delete_file_noerr(bs); |
| bdrv_co_delete_file_noerr(data_bs); |
| } else { |
| ret = 0; |
| } |
| |
| qobject_unref(qdict); |
| bdrv_unref(bs); |
| bdrv_unref(data_bs); |
| qapi_free_BlockdevCreateOptions(create_options); |
| return ret; |
| } |
| |
| |
| static bool is_zero(BlockDriverState *bs, int64_t offset, int64_t bytes) |
| { |
| int64_t nr; |
| int res; |
| |
| /* Clamp to image length, before checking status of underlying sectors */ |
| if (offset + bytes > bs->total_sectors * BDRV_SECTOR_SIZE) { |
| bytes = bs->total_sectors * BDRV_SECTOR_SIZE - offset; |
| } |
| |
| if (!bytes) { |
| return true; |
| } |
| |
| /* |
| * bdrv_block_status_above doesn't merge different types of zeros, for |
| * example, zeros which come from the region which is unallocated in |
| * the whole backing chain, and zeros which come because of a short |
| * backing file. So, we need a loop. |
| */ |
| do { |
| res = bdrv_block_status_above(bs, NULL, offset, bytes, &nr, NULL, NULL); |
| offset += nr; |
| bytes -= nr; |
| } while (res >= 0 && (res & BDRV_BLOCK_ZERO) && nr && bytes); |
| |
| return res >= 0 && (res & BDRV_BLOCK_ZERO) && bytes == 0; |
| } |
| |
| static coroutine_fn int qcow2_co_pwrite_zeroes(BlockDriverState *bs, |
| int64_t offset, int bytes, BdrvRequestFlags flags) |
| { |
| int ret; |
| BDRVQcow2State *s = bs->opaque; |
| |
| uint32_t head = offset_into_subcluster(s, offset); |
| uint32_t tail = ROUND_UP(offset + bytes, s->subcluster_size) - |
| (offset + bytes); |
| |
| trace_qcow2_pwrite_zeroes_start_req(qemu_coroutine_self(), offset, bytes); |
| if (offset + bytes == bs->total_sectors * BDRV_SECTOR_SIZE) { |
| tail = 0; |
| } |
| |
| if (head || tail) { |
| uint64_t off; |
| unsigned int nr; |
| QCow2SubclusterType type; |
| |
| assert(head + bytes + tail <= s->subcluster_size); |
| |
| /* check whether remainder of cluster already reads as zero */ |
| if (!(is_zero(bs, offset - head, head) && |
| is_zero(bs, offset + bytes, tail))) { |
| return -ENOTSUP; |
| } |
| |
| qemu_co_mutex_lock(&s->lock); |
| /* We can have new write after previous check */ |
| offset -= head; |
| bytes = s->subcluster_size; |
| nr = s->subcluster_size; |
| ret = qcow2_get_host_offset(bs, offset, &nr, &off, &type); |
| if (ret < 0 || |
| (type != QCOW2_SUBCLUSTER_UNALLOCATED_PLAIN && |
| type != QCOW2_SUBCLUSTER_UNALLOCATED_ALLOC && |
| type != QCOW2_SUBCLUSTER_ZERO_PLAIN && |
| type != QCOW2_SUBCLUSTER_ZERO_ALLOC)) { |
| qemu_co_mutex_unlock(&s->lock); |
| return ret < 0 ? ret : -ENOTSUP; |
| } |
| } else { |
| qemu_co_mutex_lock(&s->lock); |
| } |
| |
| trace_qcow2_pwrite_zeroes(qemu_coroutine_self(), offset, bytes); |
| |
| /* Whatever is left can use real zero subclusters */ |
| ret = qcow2_subcluster_zeroize(bs, offset, bytes, flags); |
| qemu_co_mutex_unlock(&s->lock); |
| |
| return ret; |
| } |
| |
| static coroutine_fn int qcow2_co_pdiscard(BlockDriverState *bs, |
| int64_t offset, int bytes) |
| { |
| int ret; |
| BDRVQcow2State *s = bs->opaque; |
| |
| /* If the image does not support QCOW_OFLAG_ZERO then discarding |
| * clusters could expose stale data from the backing file. */ |
| if (s->qcow_version < 3 && bs->backing) { |
| return -ENOTSUP; |
| } |
| |
| if (!QEMU_IS_ALIGNED(offset | bytes, s->cluster_size)) { |
| assert(bytes < s->cluster_size); |
| /* Ignore partial clusters, except for the special case of the |
| * complete partial cluster at the end of an unaligned file */ |
| if (!QEMU_IS_ALIGNED(offset, s->cluster_size) || |
| offset + bytes != bs->total_sectors * BDRV_SECTOR_SIZE) { |
| return -ENOTSUP; |
| } |
| } |
| |
| qemu_co_mutex_lock(&s->lock); |
| ret = qcow2_cluster_discard(bs, offset, bytes, QCOW2_DISCARD_REQUEST, |
| false); |
| qemu_co_mutex_unlock(&s->lock); |
| return ret; |
| } |
| |
| static int coroutine_fn |
| qcow2_co_copy_range_from(BlockDriverState *bs, |
| BdrvChild *src, uint64_t src_offset, |
| BdrvChild *dst, uint64_t dst_offset, |
| uint64_t bytes, BdrvRequestFlags read_flags, |
| BdrvRequestFlags write_flags) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int ret; |
| unsigned int cur_bytes; /* number of bytes in current iteration */ |
| BdrvChild *child = NULL; |
| BdrvRequestFlags cur_write_flags; |
| |
| assert(!bs->encrypted); |
| qemu_co_mutex_lock(&s->lock); |
| |
| while (bytes != 0) { |
| uint64_t copy_offset = 0; |
| QCow2SubclusterType type; |
| /* prepare next request */ |
| cur_bytes = MIN(bytes, INT_MAX); |
| cur_write_flags = write_flags; |
| |
| ret = qcow2_get_host_offset(bs, src_offset, &cur_bytes, |
| ©_offset, &type); |
| if (ret < 0) { |
| goto out; |
| } |
| |
| switch (type) { |
| case QCOW2_SUBCLUSTER_UNALLOCATED_PLAIN: |
| case QCOW2_SUBCLUSTER_UNALLOCATED_ALLOC: |
| if (bs->backing && bs->backing->bs) { |
| int64_t backing_length = bdrv_getlength(bs->backing->bs); |
| if (src_offset >= backing_length) { |
| cur_write_flags |= BDRV_REQ_ZERO_WRITE; |
| } else { |
| child = bs->backing; |
| cur_bytes = MIN(cur_bytes, backing_length - src_offset); |
| copy_offset = src_offset; |
| } |
| } else { |
| cur_write_flags |= BDRV_REQ_ZERO_WRITE; |
| } |
| break; |
| |
| case QCOW2_SUBCLUSTER_ZERO_PLAIN: |
| case QCOW2_SUBCLUSTER_ZERO_ALLOC: |
| cur_write_flags |= BDRV_REQ_ZERO_WRITE; |
| break; |
| |
| case QCOW2_SUBCLUSTER_COMPRESSED: |
| ret = -ENOTSUP; |
| goto out; |
| |
| case QCOW2_SUBCLUSTER_NORMAL: |
| child = s->data_file; |
| break; |
| |
| default: |
| abort(); |
| } |
| qemu_co_mutex_unlock(&s->lock); |
| ret = bdrv_co_copy_range_from(child, |
| copy_offset, |
| dst, dst_offset, |
| cur_bytes, read_flags, cur_write_flags); |
| qemu_co_mutex_lock(&s->lock); |
| if (ret < 0) { |
| goto out; |
| } |
| |
| bytes -= cur_bytes; |
| src_offset += cur_bytes; |
| dst_offset += cur_bytes; |
| } |
| ret = 0; |
| |
| out: |
| qemu_co_mutex_unlock(&s->lock); |
| return ret; |
| } |
| |
| static int coroutine_fn |
| qcow2_co_copy_range_to(BlockDriverState *bs, |
| BdrvChild *src, uint64_t src_offset, |
| BdrvChild *dst, uint64_t dst_offset, |
| uint64_t bytes, BdrvRequestFlags read_flags, |
| BdrvRequestFlags write_flags) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int ret; |
| unsigned int cur_bytes; /* number of sectors in current iteration */ |
| uint64_t host_offset; |
| QCowL2Meta *l2meta = NULL; |
| |
| assert(!bs->encrypted); |
| |
| qemu_co_mutex_lock(&s->lock); |
| |
| while (bytes != 0) { |
| |
| l2meta = NULL; |
| |
| cur_bytes = MIN(bytes, INT_MAX); |
| |
| /* TODO: |
| * If src->bs == dst->bs, we could simply copy by incrementing |
| * the refcnt, without copying user data. |
| * Or if src->bs == dst->bs->backing->bs, we could copy by discarding. */ |
| ret = qcow2_alloc_host_offset(bs, dst_offset, &cur_bytes, |
| &host_offset, &l2meta); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = qcow2_pre_write_overlap_check(bs, 0, host_offset, cur_bytes, |
| true); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| qemu_co_mutex_unlock(&s->lock); |
| ret = bdrv_co_copy_range_to(src, src_offset, s->data_file, host_offset, |
| cur_bytes, read_flags, write_flags); |
| qemu_co_mutex_lock(&s->lock); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = qcow2_handle_l2meta(bs, &l2meta, true); |
| if (ret) { |
| goto fail; |
| } |
| |
| bytes -= cur_bytes; |
| src_offset += cur_bytes; |
| dst_offset += cur_bytes; |
| } |
| ret = 0; |
| |
| fail: |
| qcow2_handle_l2meta(bs, &l2meta, false); |
| |
| qemu_co_mutex_unlock(&s->lock); |
| |
| trace_qcow2_writev_done_req(qemu_coroutine_self(), ret); |
| |
| return ret; |
| } |
| |
| static int coroutine_fn qcow2_co_truncate(BlockDriverState *bs, int64_t offset, |
| bool exact, PreallocMode prealloc, |
| BdrvRequestFlags flags, Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| uint64_t old_length; |
| int64_t new_l1_size; |
| int ret; |
| QDict *options; |
| |
| if (prealloc != PREALLOC_MODE_OFF && prealloc != PREALLOC_MODE_METADATA && |
| prealloc != PREALLOC_MODE_FALLOC && prealloc != PREALLOC_MODE_FULL) |
| { |
| error_setg(errp, "Unsupported preallocation mode '%s'", |
| PreallocMode_str(prealloc)); |
| return -ENOTSUP; |
| } |
| |
| if (!QEMU_IS_ALIGNED(offset, BDRV_SECTOR_SIZE)) { |
| error_setg(errp, "The new size must be a multiple of %u", |
| (unsigned) BDRV_SECTOR_SIZE); |
| return -EINVAL; |
| } |
| |
| qemu_co_mutex_lock(&s->lock); |
| |
| /* |
| * Even though we store snapshot size for all images, it was not |
| * required until v3, so it is not safe to proceed for v2. |
| */ |
| if (s->nb_snapshots && s->qcow_version < 3) { |
| error_setg(errp, "Can't resize a v2 image which has snapshots"); |
| ret = -ENOTSUP; |
| goto fail; |
| } |
| |
| /* See qcow2-bitmap.c for which bitmap scenarios prevent a resize. */ |
| if (qcow2_truncate_bitmaps_check(bs, errp)) { |
| ret = -ENOTSUP; |
| goto fail; |
| } |
| |
| old_length = bs->total_sectors * BDRV_SECTOR_SIZE; |
| new_l1_size = size_to_l1(s, offset); |
| |
| if (offset < old_length) { |
| int64_t last_cluster, old_file_size; |
| if (prealloc != PREALLOC_MODE_OFF) { |
| error_setg(errp, |
| "Preallocation can't be used for shrinking an image"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| ret = qcow2_cluster_discard(bs, ROUND_UP(offset, s->cluster_size), |
| old_length - ROUND_UP(offset, |
| s->cluster_size), |
| QCOW2_DISCARD_ALWAYS, true); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to discard cropped clusters"); |
| goto fail; |
| } |
| |
| ret = qcow2_shrink_l1_table(bs, new_l1_size); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, |
| "Failed to reduce the number of L2 tables"); |
| goto fail; |
| } |
| |
| ret = qcow2_shrink_reftable(bs); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, |
| "Failed to discard unused refblocks"); |
| goto fail; |
| } |
| |
| old_file_size = bdrv_getlength(bs->file->bs); |
| if (old_file_size < 0) { |
| error_setg_errno(errp, -old_file_size, |
| "Failed to inquire current file length"); |
| ret = old_file_size; |
| goto fail; |
| } |
| last_cluster = qcow2_get_last_cluster(bs, old_file_size); |
| if (last_cluster < 0) { |
| error_setg_errno(errp, -last_cluster, |
| "Failed to find the last cluster"); |
| ret = last_cluster; |
| goto fail; |
| } |
| if ((last_cluster + 1) * s->cluster_size < old_file_size) { |
| Error *local_err = NULL; |
| |
| /* |
| * Do not pass @exact here: It will not help the user if |
| * we get an error here just because they wanted to shrink |
| * their qcow2 image (on a block device) with qemu-img. |
| * (And on the qcow2 layer, the @exact requirement is |
| * always fulfilled, so there is no need to pass it on.) |
| */ |
| bdrv_co_truncate(bs->file, (last_cluster + 1) * s->cluster_size, |
| false, PREALLOC_MODE_OFF, 0, &local_err); |
| if (local_err) { |
| warn_reportf_err(local_err, |
| "Failed to truncate the tail of the image: "); |
| } |
| } |
| } else { |
| ret = qcow2_grow_l1_table(bs, new_l1_size, true); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to grow the L1 table"); |
| goto fail; |
| } |
| |
| if (data_file_is_raw(bs) && prealloc == PREALLOC_MODE_OFF) { |
| /* |
| * When creating a qcow2 image with data-file-raw, we enforce |
| * at least prealloc=metadata, so that the L1/L2 tables are |
| * fully allocated and reading from the data file will return |
| * the same data as reading from the qcow2 image. When the |
| * image is grown, we must consequently preallocate the |
| * metadata structures to cover the added area. |
| */ |
| prealloc = PREALLOC_MODE_METADATA; |
| } |
| } |
| |
| switch (prealloc) { |
| case PREALLOC_MODE_OFF: |
| if (has_data_file(bs)) { |
| /* |
| * If the caller wants an exact resize, the external data |
| * file should be resized to the exact target size, too, |
| * so we pass @exact here. |
| */ |
| ret = bdrv_co_truncate(s->data_file, offset, exact, prealloc, 0, |
| errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| } |
| break; |
| |
| case PREALLOC_MODE_METADATA: |
| ret = preallocate_co(bs, old_length, offset, prealloc, errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| break; |
| |
| case PREALLOC_MODE_FALLOC: |
| case PREALLOC_MODE_FULL: |
| { |
| int64_t allocation_start, host_offset, guest_offset; |
| int64_t clusters_allocated; |
| int64_t old_file_size, last_cluster, new_file_size; |
| uint64_t nb_new_data_clusters, nb_new_l2_tables; |
| bool subclusters_need_allocation = false; |
| |
| /* With a data file, preallocation means just allocating the metadata |
| * and forwarding the truncate request to the data file */ |
| if (has_data_file(bs)) { |
| ret = preallocate_co(bs, old_length, offset, prealloc, errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| break; |
| } |
| |
| old_file_size = bdrv_getlength(bs->file->bs); |
| if (old_file_size < 0) { |
| error_setg_errno(errp, -old_file_size, |
| "Failed to inquire current file length"); |
| ret = old_file_size; |
| goto fail; |
| } |
| |
| last_cluster = qcow2_get_last_cluster(bs, old_file_size); |
| if (last_cluster >= 0) { |
| old_file_size = (last_cluster + 1) * s->cluster_size; |
| } else { |
| old_file_size = ROUND_UP(old_file_size, s->cluster_size); |
| } |
| |
| nb_new_data_clusters = (ROUND_UP(offset, s->cluster_size) - |
| start_of_cluster(s, old_length)) >> s->cluster_bits; |
| |
| /* This is an overestimation; we will not actually allocate space for |
| * these in the file but just make sure the new refcount structures are |
| * able to cover them so we will not have to allocate new refblocks |
| * while entering the data blocks in the potentially new L2 tables. |
| * (We do not actually care where the L2 tables are placed. Maybe they |
| * are already allocated or they can be placed somewhere before |
| * @old_file_size. It does not matter because they will be fully |
| * allocated automatically, so they do not need to be covered by the |
| * preallocation. All that matters is that we will not have to allocate |
| * new refcount structures for them.) */ |
| nb_new_l2_tables = DIV_ROUND_UP(nb_new_data_clusters, |
| s->cluster_size / l2_entry_size(s)); |
| /* The cluster range may not be aligned to L2 boundaries, so add one L2 |
| * table for a potential head/tail */ |
| nb_new_l2_tables++; |
| |
| allocation_start = qcow2_refcount_area(bs, old_file_size, |
| nb_new_data_clusters + |
| nb_new_l2_tables, |
| true, 0, 0); |
| if (allocation_start < 0) { |
| error_setg_errno(errp, -allocation_start, |
| "Failed to resize refcount structures"); |
| ret = allocation_start; |
| goto fail; |
| } |
| |
| clusters_allocated = qcow2_alloc_clusters_at(bs, allocation_start, |
| nb_new_data_clusters); |
| if (clusters_allocated < 0) { |
| error_setg_errno(errp, -clusters_allocated, |
| "Failed to allocate data clusters"); |
| ret = clusters_allocated; |
| goto fail; |
| } |
| |
| assert(clusters_allocated == nb_new_data_clusters); |
| |
| /* Allocate the data area */ |
| new_file_size = allocation_start + |
| nb_new_data_clusters * s->cluster_size; |
| /* |
| * Image file grows, so @exact does not matter. |
| * |
| * If we need to zero out the new area, try first whether the protocol |
| * driver can already take care of this. |
| */ |
| if (flags & BDRV_REQ_ZERO_WRITE) { |
| ret = bdrv_co_truncate(bs->file, new_file_size, false, prealloc, |
| BDRV_REQ_ZERO_WRITE, NULL); |
| if (ret >= 0) { |
| flags &= ~BDRV_REQ_ZERO_WRITE; |
| /* Ensure that we read zeroes and not backing file data */ |
| subclusters_need_allocation = true; |
| } |
| } else { |
| ret = -1; |
| } |
| if (ret < 0) { |
| ret = bdrv_co_truncate(bs->file, new_file_size, false, prealloc, 0, |
| errp); |
| } |
| if (ret < 0) { |
| error_prepend(errp, "Failed to resize underlying file: "); |
| qcow2_free_clusters(bs, allocation_start, |
| nb_new_data_clusters * s->cluster_size, |
| QCOW2_DISCARD_OTHER); |
| goto fail; |
| } |
| |
| /* Create the necessary L2 entries */ |
| host_offset = allocation_start; |
| guest_offset = old_length; |
| while (nb_new_data_clusters) { |
| int64_t nb_clusters = MIN( |
| nb_new_data_clusters, |
| s->l2_slice_size - offset_to_l2_slice_index(s, guest_offset)); |
| unsigned cow_start_length = offset_into_cluster(s, guest_offset); |
| QCowL2Meta allocation; |
| guest_offset = start_of_cluster(s, guest_offset); |
| allocation = (QCowL2Meta) { |
| .offset = guest_offset, |
| .alloc_offset = host_offset, |
| .nb_clusters = nb_clusters, |
| .cow_start = { |
| .offset = 0, |
| .nb_bytes = cow_start_length, |
| }, |
| .cow_end = { |
| .offset = nb_clusters << s->cluster_bits, |
| .nb_bytes = 0, |
| }, |
| .prealloc = !subclusters_need_allocation, |
| }; |
| qemu_co_queue_init(&allocation.dependent_requests); |
| |
| ret = qcow2_alloc_cluster_link_l2(bs, &allocation); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to update L2 tables"); |
| qcow2_free_clusters(bs, host_offset, |
| nb_new_data_clusters * s->cluster_size, |
| QCOW2_DISCARD_OTHER); |
| goto fail; |
| } |
| |
| guest_offset += nb_clusters * s->cluster_size; |
| host_offset += nb_clusters * s->cluster_size; |
| nb_new_data_clusters -= nb_clusters; |
| } |
| break; |
| } |
| |
| default: |
| g_assert_not_reached(); |
| } |
| |
| if ((flags & BDRV_REQ_ZERO_WRITE) && offset > old_length) { |
| uint64_t zero_start = QEMU_ALIGN_UP(old_length, s->subcluster_size); |
| |
| /* |
| * Use zero clusters as much as we can. qcow2_subcluster_zeroize() |
| * requires a subcluster-aligned start. The end may be unaligned if |
| * it is at the end of the image (which it is here). |
| */ |
| if (offset > zero_start) { |
| ret = qcow2_subcluster_zeroize(bs, zero_start, offset - zero_start, |
| 0); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to zero out new clusters"); |
| goto fail; |
| } |
| } |
| |
| /* Write explicit zeros for the unaligned head */ |
| if (zero_start > old_length) { |
| uint64_t len = MIN(zero_start, offset) - old_length; |
| uint8_t *buf = qemu_blockalign0(bs, len); |
| QEMUIOVector qiov; |
| qemu_iovec_init_buf(&qiov, buf, len); |
| |
| qemu_co_mutex_unlock(&s->lock); |
| ret = qcow2_co_pwritev_part(bs, old_length, len, &qiov, 0, 0); |
| qemu_co_mutex_lock(&s->lock); |
| |
| qemu_vfree(buf); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to zero out the new area"); |
| goto fail; |
| } |
| } |
| } |
| |
| if (prealloc != PREALLOC_MODE_OFF) { |
| /* Flush metadata before actually changing the image size */ |
| ret = qcow2_write_caches(bs); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, |
| "Failed to flush the preallocated area to disk"); |
| goto fail; |
| } |
| } |
| |
| bs->total_sectors = offset / BDRV_SECTOR_SIZE; |
| |
| /* write updated header.size */ |
| offset = cpu_to_be64(offset); |
| ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size), |
| &offset, sizeof(offset)); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to update the image size"); |
| goto fail; |
| } |
| |
| s->l1_vm_state_index = new_l1_size; |
| |
| /* Update cache sizes */ |
| options = qdict_clone_shallow(bs->options); |
| ret = qcow2_update_options(bs, options, s->flags, errp); |
| qobject_unref(options); |
| if (ret < 0) { |
| goto fail; |
| } |
| ret = 0; |
| fail: |
| qemu_co_mutex_unlock(&s->lock); |
| return ret; |
| } |
| |
| static coroutine_fn int |
| qcow2_co_pwritev_compressed_task(BlockDriverState *bs, |
| uint64_t offset, uint64_t bytes, |
| QEMUIOVector *qiov, size_t qiov_offset) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int ret; |
| ssize_t out_len; |
| uint8_t *buf, *out_buf; |
| uint64_t cluster_offset; |
| |
| assert(bytes == s->cluster_size || (bytes < s->cluster_size && |
| (offset + bytes == bs->total_sectors << BDRV_SECTOR_BITS))); |
| |
| buf = qemu_blockalign(bs, s->cluster_size); |
| if (bytes < s->cluster_size) { |
| /* Zero-pad last write if image size is not cluster aligned */ |
| memset(buf + bytes, 0, s->cluster_size - bytes); |
| } |
| qemu_iovec_to_buf(qiov, qiov_offset, buf, bytes); |
| |
| out_buf = g_malloc(s->cluster_size); |
| |
| out_len = qcow2_co_compress(bs, out_buf, s->cluster_size - 1, |
| buf, s->cluster_size); |
| if (out_len == -ENOMEM) { |
| /* could not compress: write normal cluster */ |
| ret = qcow2_co_pwritev_part(bs, offset, bytes, qiov, qiov_offset, 0); |
| if (ret < 0) { |
| goto fail; |
| } |
| goto success; |
| } else if (out_len < 0) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| qemu_co_mutex_lock(&s->lock); |
| ret = qcow2_alloc_compressed_cluster_offset(bs, offset, out_len, |
| &cluster_offset); |
| if (ret < 0) { |
| qemu_co_mutex_unlock(&s->lock); |
| goto fail; |
| } |
| |
| ret = qcow2_pre_write_overlap_check(bs, 0, cluster_offset, out_len, true); |
| qemu_co_mutex_unlock(&s->lock); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| BLKDBG_EVENT(s->data_file, BLKDBG_WRITE_COMPRESSED); |
| ret = bdrv_co_pwrite(s->data_file, cluster_offset, out_len, out_buf, 0); |
| if (ret < 0) { |
| goto fail; |
| } |
| success: |
| ret = 0; |
| fail: |
| qemu_vfree(buf); |
| g_free(out_buf); |
| return ret; |
| } |
| |
| static coroutine_fn int qcow2_co_pwritev_compressed_task_entry(AioTask *task) |
| { |
| Qcow2AioTask *t = container_of(task, Qcow2AioTask, task); |
| |
| assert(!t->subcluster_type && !t->l2meta); |
| |
| return qcow2_co_pwritev_compressed_task(t->bs, t->offset, t->bytes, t->qiov, |
| t->qiov_offset); |
| } |
| |
| /* |
| * XXX: put compressed sectors first, then all the cluster aligned |
| * tables to avoid losing bytes in alignment |
| */ |
| static coroutine_fn int |
| qcow2_co_pwritev_compressed_part(BlockDriverState *bs, |
| uint64_t offset, uint64_t bytes, |
| QEMUIOVector *qiov, size_t qiov_offset) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| AioTaskPool *aio = NULL; |
| int ret = 0; |
| |
| if (has_data_file(bs)) { |
| return -ENOTSUP; |
| } |
| |
| if (bytes == 0) { |
| /* |
| * align end of file to a sector boundary to ease reading with |
| * sector based I/Os |
| */ |
| int64_t len = bdrv_getlength(bs->file->bs); |
| if (len < 0) { |
| return len; |
| } |
| return bdrv_co_truncate(bs->file, len, false, PREALLOC_MODE_OFF, 0, |
| NULL); |
| } |
| |
| if (offset_into_cluster(s, offset)) { |
| return -EINVAL; |
| } |
| |
| if (offset_into_cluster(s, bytes) && |
| (offset + bytes) != (bs->total_sectors << BDRV_SECTOR_BITS)) { |
| return -EINVAL; |
| } |
| |
| while (bytes && aio_task_pool_status(aio) == 0) { |
| uint64_t chunk_size = MIN(bytes, s->cluster_size); |
| |
| if (!aio && chunk_size != bytes) { |
| aio = aio_task_pool_new(QCOW2_MAX_WORKERS); |
| } |
| |
| ret = qcow2_add_task(bs, aio, qcow2_co_pwritev_compressed_task_entry, |
| 0, 0, offset, chunk_size, qiov, qiov_offset, NULL); |
| if (ret < 0) { |
| break; |
| } |
| qiov_offset += chunk_size; |
| offset += chunk_size; |
| bytes -= chunk_size; |
| } |
| |
| if (aio) { |
| aio_task_pool_wait_all(aio); |
| if (ret == 0) { |
| ret = aio_task_pool_status(aio); |
| } |
| g_free(aio); |
| } |
| |
| return ret; |
| } |
| |
| static int coroutine_fn |
| qcow2_co_preadv_compressed(BlockDriverState *bs, |
| uint64_t cluster_descriptor, |
| uint64_t offset, |
| uint64_t bytes, |
| QEMUIOVector *qiov, |
| size_t qiov_offset) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int ret = 0, csize, nb_csectors; |
| uint64_t coffset; |
| uint8_t *buf, *out_buf; |
| int offset_in_cluster = offset_into_cluster(s, offset); |
| |
| coffset = cluster_descriptor & s->cluster_offset_mask; |
| nb_csectors = ((cluster_descriptor >> s->csize_shift) & s->csize_mask) + 1; |
| csize = nb_csectors * QCOW2_COMPRESSED_SECTOR_SIZE - |
| (coffset & ~QCOW2_COMPRESSED_SECTOR_MASK); |
| |
| buf = g_try_malloc(csize); |
| if (!buf) { |
| return -ENOMEM; |
| } |
| |
| out_buf = qemu_blockalign(bs, s->cluster_size); |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_READ_COMPRESSED); |
| ret = bdrv_co_pread(bs->file, coffset, csize, buf, 0); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| if (qcow2_co_decompress(bs, out_buf, s->cluster_size, buf, csize) < 0) { |
| ret = -EIO; |
| goto fail; |
| } |
| |
| qemu_iovec_from_buf(qiov, qiov_offset, out_buf + offset_in_cluster, bytes); |
| |
| fail: |
| qemu_vfree(out_buf); |
| g_free(buf); |
| |
| return ret; |
| } |
| |
| static int make_completely_empty(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| Error *local_err = NULL; |
| int ret, l1_clusters; |
| int64_t offset; |
| uint64_t *new_reftable = NULL; |
| uint64_t rt_entry, l1_size2; |
| struct { |
| uint64_t l1_offset; |
| uint64_t reftable_offset; |
| uint32_t reftable_clusters; |
| } QEMU_PACKED l1_ofs_rt_ofs_cls; |
| |
| ret = qcow2_cache_empty(bs, s->l2_table_cache); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = qcow2_cache_empty(bs, s->refcount_block_cache); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| /* Refcounts will be broken utterly */ |
| ret = qcow2_mark_dirty(bs); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_L1_UPDATE); |
| |
| l1_clusters = DIV_ROUND_UP(s->l1_size, s->cluster_size / L1E_SIZE); |
| l1_size2 = (uint64_t)s->l1_size * L1E_SIZE; |
| |
| /* After this call, neither the in-memory nor the on-disk refcount |
| * information accurately describe the actual references */ |
| |
| ret = bdrv_pwrite_zeroes(bs->file, s->l1_table_offset, |
| l1_clusters * s->cluster_size, 0); |
| if (ret < 0) { |
| goto fail_broken_refcounts; |
| } |
| memset(s->l1_table, 0, l1_size2); |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_EMPTY_IMAGE_PREPARE); |
| |
| /* Overwrite enough clusters at the beginning of the sectors to place |
| * the refcount table, a refcount block and the L1 table in; this may |
| * overwrite parts of the existing refcount and L1 table, which is not |
| * an issue because the dirty flag is set, complete data loss is in fact |
| * desired and partial data loss is consequently fine as well */ |
| ret = bdrv_pwrite_zeroes(bs->file, s->cluster_size, |
| (2 + l1_clusters) * s->cluster_size, 0); |
| /* This call (even if it failed overall) may have overwritten on-disk |
| * refcount structures; in that case, the in-memory refcount information |
| * will probably differ from the on-disk information which makes the BDS |
| * unusable */ |
| if (ret < 0) { |
| goto fail_broken_refcounts; |
| } |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_L1_UPDATE); |
| BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_UPDATE); |
| |
| /* "Create" an empty reftable (one cluster) directly after the image |
| * header and an empty L1 table three clusters after the image header; |
| * the cluster between those two will be used as the first refblock */ |
| l1_ofs_rt_ofs_cls.l1_offset = cpu_to_be64(3 * s->cluster_size); |
| l1_ofs_rt_ofs_cls.reftable_offset = cpu_to_be64(s->cluster_size); |
| l1_ofs_rt_ofs_cls.reftable_clusters = cpu_to_be32(1); |
| ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, l1_table_offset), |
| &l1_ofs_rt_ofs_cls, sizeof(l1_ofs_rt_ofs_cls)); |
| if (ret < 0) { |
| goto fail_broken_refcounts; |
| } |
| |
| s->l1_table_offset = 3 * s->cluster_size; |
| |
| new_reftable = g_try_new0(uint64_t, s->cluster_size / REFTABLE_ENTRY_SIZE); |
| if (!new_reftable) { |
| ret = -ENOMEM; |
| goto fail_broken_refcounts; |
| } |
| |
| s->refcount_table_offset = s->cluster_size; |
| s->refcount_table_size = s->cluster_size / REFTABLE_ENTRY_SIZE; |
| s->max_refcount_table_index = 0; |
| |
| g_free(s->refcount_table); |
| s->refcount_table = new_reftable; |
| new_reftable = NULL; |
| |
| /* Now the in-memory refcount information again corresponds to the on-disk |
| * information (reftable is empty and no refblocks (the refblock cache is |
| * empty)); however, this means some clusters (e.g. the image header) are |
| * referenced, but not refcounted, but the normal qcow2 code assumes that |
| * the in-memory information is always correct */ |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC); |
| |
| /* Enter the first refblock into the reftable */ |
| rt_entry = cpu_to_be64(2 * s->cluster_size); |
| ret = bdrv_pwrite_sync(bs->file, s->cluster_size, |
| &rt_entry, sizeof(rt_entry)); |
| if (ret < 0) { |
| goto fail_broken_refcounts; |
| } |
| s->refcount_table[0] = 2 * s->cluster_size; |
| |
| s->free_cluster_index = 0; |
| assert(3 + l1_clusters <= s->refcount_block_size); |
| offset = qcow2_alloc_clusters(bs, 3 * s->cluster_size + l1_size2); |
| if (offset < 0) { |
| ret = offset; |
| goto fail_broken_refcounts; |
| } else if (offset > 0) { |
| error_report("First cluster in emptied image is in use"); |
| abort(); |
| } |
| |
| /* Now finally the in-memory information corresponds to the on-disk |
| * structures and is correct */ |
| ret = qcow2_mark_clean(bs); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = bdrv_truncate(bs->file, (3 + l1_clusters) * s->cluster_size, false, |
| PREALLOC_MODE_OFF, 0, &local_err); |
| if (ret < 0) { |
| error_report_err(local_err); |
| goto fail; |
| } |
| |
| return 0; |
| |
| fail_broken_refcounts: |
| /* The BDS is unusable at this point. If we wanted to make it usable, we |
| * would have to call qcow2_refcount_close(), qcow2_refcount_init(), |
| * qcow2_check_refcounts(), qcow2_refcount_close() and qcow2_refcount_init() |
| * again. However, because the functions which could have caused this error |
| * path to be taken are used by those functions as well, it's very likely |
| * that that sequence will fail as well. Therefore, just eject the BDS. */ |
| bs->drv = NULL; |
| |
| fail: |
| g_free(new_reftable); |
| return ret; |
| } |
| |
| static int qcow2_make_empty(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| uint64_t offset, end_offset; |
| int step = QEMU_ALIGN_DOWN(INT_MAX, s->cluster_size); |
| int l1_clusters, ret = 0; |
| |
| l1_clusters = DIV_ROUND_UP(s->l1_size, s->cluster_size / L1E_SIZE); |
| |
| if (s->qcow_version >= 3 && !s->snapshots && !s->nb_bitmaps && |
| 3 + l1_clusters <= s->refcount_block_size && |
| s->crypt_method_header != QCOW_CRYPT_LUKS && |
| !has_data_file(bs)) { |
| /* The following function only works for qcow2 v3 images (it |
| * requires the dirty flag) and only as long as there are no |
| * features that reserve extra clusters (such as snapshots, |
| * LUKS header, or persistent bitmaps), because it completely |
| * empties the image. Furthermore, the L1 table and three |
| * additional clusters (image header, refcount table, one |
| * refcount block) have to fit inside one refcount block. It |
| * only resets the image file, i.e. does not work with an |
| * external data file. */ |
| return make_completely_empty(bs); |
| } |
| |
| /* This fallback code simply discards every active cluster; this is slow, |
| * but works in all cases */ |
| end_offset = bs->total_sectors * BDRV_SECTOR_SIZE; |
| for (offset = 0; offset < end_offset; offset += step) { |
| /* As this function is generally used after committing an external |
| * snapshot, QCOW2_DISCARD_SNAPSHOT seems appropriate. Also, the |
| * default action for this kind of discard is to pass the discard, |
| * which will ideally result in an actually smaller image file, as |
| * is probably desired. */ |
| ret = qcow2_cluster_discard(bs, offset, MIN(step, end_offset - offset), |
| QCOW2_DISCARD_SNAPSHOT, true); |
| if (ret < 0) { |
| break; |
| } |
| } |
| |
| return ret; |
| } |
| |
| static coroutine_fn int qcow2_co_flush_to_os(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int ret; |
| |
| qemu_co_mutex_lock(&s->lock); |
| ret = qcow2_write_caches(bs); |
| qemu_co_mutex_unlock(&s->lock); |
| |
| return ret; |
| } |
| |
| static BlockMeasureInfo *qcow2_measure(QemuOpts *opts, BlockDriverState *in_bs, |
| Error **errp) |
| { |
| Error *local_err = NULL; |
| BlockMeasureInfo *info; |
| uint64_t required = 0; /* bytes that contribute to required size */ |
| uint64_t virtual_size; /* disk size as seen by guest */ |
| uint64_t refcount_bits; |
| uint64_t l2_tables; |
| uint64_t luks_payload_size = 0; |
| size_t cluster_size; |
| int version; |
| char *optstr; |
| PreallocMode prealloc; |
| bool has_backing_file; |
| bool has_luks; |
| bool extended_l2; |
| size_t l2e_size; |
| |
| /* Parse image creation options */ |
| extended_l2 = qemu_opt_get_bool_del(opts, BLOCK_OPT_EXTL2, false); |
| |
| cluster_size = qcow2_opt_get_cluster_size_del(opts, extended_l2, |
| &local_err); |
| if (local_err) { |
| goto err; |
| } |
| |
| version = qcow2_opt_get_version_del(opts, &local_err); |
| if (local_err) { |
| goto err; |
| } |
| |
| refcount_bits = qcow2_opt_get_refcount_bits_del(opts, version, &local_err); |
| if (local_err) { |
| goto err; |
| } |
| |
| optstr = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC); |
| prealloc = qapi_enum_parse(&PreallocMode_lookup, optstr, |
| PREALLOC_MODE_OFF, &local_err); |
| g_free(optstr); |
| if (local_err) { |
| goto err; |
| } |
| |
| optstr = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FILE); |
| has_backing_file = !!optstr; |
| g_free(optstr); |
| |
| optstr = qemu_opt_get_del(opts, BLOCK_OPT_ENCRYPT_FORMAT); |
| has_luks = optstr && strcmp(optstr, "luks") == 0; |
| g_free(optstr); |
| |
| if (has_luks) { |
| g_autoptr(QCryptoBlockCreateOptions) create_opts = NULL; |
| QDict *cryptoopts = qcow2_extract_crypto_opts(opts, "luks", errp); |
| size_t headerlen; |
| |
| create_opts = block_crypto_create_opts_init(cryptoopts, errp); |
| qobject_unref(cryptoopts); |
| if (!create_opts) { |
| goto err; |
| } |
| |
| if (!qcrypto_block_calculate_payload_offset(create_opts, |
| "encrypt.", |
| &headerlen, |
| &local_err)) { |
| goto err; |
| } |
| |
| luks_payload_size = ROUND_UP(headerlen, cluster_size); |
| } |
| |
| virtual_size = qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0); |
| virtual_size = ROUND_UP(virtual_size, cluster_size); |
| |
| /* Check that virtual disk size is valid */ |
| l2e_size = extended_l2 ? L2E_SIZE_EXTENDED : L2E_SIZE_NORMAL; |
| l2_tables = DIV_ROUND_UP(virtual_size / cluster_size, |
| cluster_size / l2e_size); |
| if (l2_tables * L1E_SIZE > QCOW_MAX_L1_SIZE) { |
| error_setg(&local_err, "The image size is too large " |
| "(try using a larger cluster size)"); |
| goto err; |
| } |
| |
| /* Account for input image */ |
| if (in_bs) { |
| int64_t ssize = bdrv_getlength(in_bs); |
| if (ssize < 0) { |
| error_setg_errno(&local_err, -ssize, |
| "Unable to get image virtual_size"); |
| goto err; |
| } |
| |
| virtual_size = ROUND_UP(ssize, cluster_size); |
| |
| if (has_backing_file) { |
| /* We don't how much of the backing chain is shared by the input |
| * image and the new image file. In the worst case the new image's |
| * backing file has nothing in common with the input image. Be |
| * conservative and assume all clusters need to be written. |
| */ |
| required = virtual_size; |
| } else { |
| int64_t offset; |
| int64_t pnum = 0; |
| |
| for (offset = 0; offset < ssize; offset += pnum) { |
| int ret; |
| |
| ret = bdrv_block_status_above(in_bs, NULL, offset, |
| ssize - offset, &pnum, NULL, |
| NULL); |
| if (ret < 0) { |
| error_setg_errno(&local_err, -ret, |
| "Unable to get block status"); |
| goto err; |
| } |
| |
| if (ret & BDRV_BLOCK_ZERO) { |
| /* Skip zero regions (safe with no backing file) */ |
| } else if ((ret & (BDRV_BLOCK_DATA | BDRV_BLOCK_ALLOCATED)) == |
| (BDRV_BLOCK_DATA | BDRV_BLOCK_ALLOCATED)) { |
| /* Extend pnum to end of cluster for next iteration */ |
| pnum = ROUND_UP(offset + pnum, cluster_size) - offset; |
| |
| /* Count clusters we've seen */ |
| required += offset % cluster_size + pnum; |
| } |
| } |
| } |
| } |
| |
| /* Take into account preallocation. Nothing special is needed for |
| * PREALLOC_MODE_METADATA since metadata is always counted. |
| */ |
| if (prealloc == PREALLOC_MODE_FULL || prealloc == PREALLOC_MODE_FALLOC) { |
| required = virtual_size; |
| } |
| |
| info = g_new0(BlockMeasureInfo, 1); |
| info->fully_allocated = luks_payload_size + |
| qcow2_calc_prealloc_size(virtual_size, cluster_size, |
| ctz32(refcount_bits), extended_l2); |
| |
| /* |
| * Remove data clusters that are not required. This overestimates the |
| * required size because metadata needed for the fully allocated file is |
| * still counted. Show bitmaps only if both source and destination |
| * would support them. |
| */ |
| info->required = info->fully_allocated - virtual_size + required; |
| info->has_bitmaps = version >= 3 && in_bs && |
| bdrv_supports_persistent_dirty_bitmap(in_bs); |
| if (info->has_bitmaps) { |
| info->bitmaps = qcow2_get_persistent_dirty_bitmap_size(in_bs, |
| cluster_size); |
| } |
| return info; |
| |
| err: |
| error_propagate(errp, local_err); |
| return NULL; |
| } |
| |
| static int qcow2_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| bdi->cluster_size = s->cluster_size; |
| bdi->vm_state_offset = qcow2_vm_state_offset(s); |
| bdi->is_dirty = s->incompatible_features & QCOW2_INCOMPAT_DIRTY; |
| return 0; |
| } |
| |
| static ImageInfoSpecific *qcow2_get_specific_info(BlockDriverState *bs, |
| Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| ImageInfoSpecific *spec_info; |
| QCryptoBlockInfo *encrypt_info = NULL; |
| |
| if (s->crypto != NULL) { |
| encrypt_info = qcrypto_block_get_info(s->crypto, errp); |
| if (!encrypt_info) { |
| return NULL; |
| } |
| } |
| |
| spec_info = g_new(ImageInfoSpecific, 1); |
| *spec_info = (ImageInfoSpecific){ |
| .type = IMAGE_INFO_SPECIFIC_KIND_QCOW2, |
| .u.qcow2.data = g_new0(ImageInfoSpecificQCow2, 1), |
| }; |
| if (s->qcow_version == 2) { |
| *spec_info->u.qcow2.data = (ImageInfoSpecificQCow2){ |
| .compat = g_strdup("0.10"), |
| .refcount_bits = s->refcount_bits, |
| }; |
| } else if (s->qcow_version == 3) { |
| Qcow2BitmapInfoList *bitmaps; |
| if (!qcow2_get_bitmap_info_list(bs, &bitmaps, errp)) { |
| qapi_free_ImageInfoSpecific(spec_info); |
| qapi_free_QCryptoBlockInfo(encrypt_info); |
| return NULL; |
| } |
| *spec_info->u.qcow2.data = (ImageInfoSpecificQCow2){ |
| .compat = g_strdup("1.1"), |
| .lazy_refcounts = s->compatible_features & |
| QCOW2_COMPAT_LAZY_REFCOUNTS, |
| .has_lazy_refcounts = true, |
| .corrupt = s->incompatible_features & |
| QCOW2_INCOMPAT_CORRUPT, |
| .has_corrupt = true, |
| .has_extended_l2 = true, |
| .extended_l2 = has_subclusters(s), |
| .refcount_bits = s->refcount_bits, |
| .has_bitmaps = !!bitmaps, |
| .bitmaps = bitmaps, |
| .has_data_file = !!s->image_data_file, |
| .data_file = g_strdup(s->image_data_file), |
| .has_data_file_raw = has_data_file(bs), |
| .data_file_raw = data_file_is_raw(bs), |
| .compression_type = s->compression_type, |
| }; |
| } else { |
| /* if this assertion fails, this probably means a new version was |
| * added without having it covered here */ |
| assert(false); |
| } |
| |
| if (encrypt_info) { |
| ImageInfoSpecificQCow2Encryption *qencrypt = |
| g_new(ImageInfoSpecificQCow2Encryption, 1); |
| switch (encrypt_info->format) { |
| case Q_CRYPTO_BLOCK_FORMAT_QCOW: |
| qencrypt->format = BLOCKDEV_QCOW2_ENCRYPTION_FORMAT_AES; |
| break; |
| case Q_CRYPTO_BLOCK_FORMAT_LUKS: |
| qencrypt->format = BLOCKDEV_QCOW2_ENCRYPTION_FORMAT_LUKS; |
| qencrypt->u.luks = encrypt_info->u.luks; |
| break; |
| default: |
| abort(); |
| } |
| /* Since we did shallow copy above, erase any pointers |
| * in the original info */ |
| memset(&encrypt_info->u, 0, sizeof(encrypt_info->u)); |
| qapi_free_QCryptoBlockInfo(encrypt_info); |
| |
| spec_info->u.qcow2.data->has_encrypt = true; |
| spec_info->u.qcow2.data->encrypt = qencrypt; |
| } |
| |
| return spec_info; |
| } |
| |
| static int qcow2_has_zero_init(BlockDriverState *bs) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| bool preallocated; |
| |
| if (qemu_in_coroutine()) { |
| qemu_co_mutex_lock(&s->lock); |
| } |
| /* |
| * Check preallocation status: Preallocated images have all L2 |
| * tables allocated, nonpreallocated images have none. It is |
| * therefore enough to check the first one. |
| */ |
| preallocated = s->l1_size > 0 && s->l1_table[0] != 0; |
| if (qemu_in_coroutine()) { |
| qemu_co_mutex_unlock(&s->lock); |
| } |
| |
| if (!preallocated) { |
| return 1; |
| } else if (bs->encrypted) { |
| return 0; |
| } else { |
| return bdrv_has_zero_init(s->data_file->bs); |
| } |
| } |
| |
| static int qcow2_save_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, |
| int64_t pos) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE); |
| return bs->drv->bdrv_co_pwritev_part(bs, qcow2_vm_state_offset(s) + pos, |
| qiov->size, qiov, 0, 0); |
| } |
| |
| static int qcow2_load_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, |
| int64_t pos) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_LOAD); |
| return bs->drv->bdrv_co_preadv_part(bs, qcow2_vm_state_offset(s) + pos, |
| qiov->size, qiov, 0, 0); |
| } |
| |
| /* |
| * Downgrades an image's version. To achieve this, any incompatible features |
| * have to be removed. |
| */ |
| static int qcow2_downgrade(BlockDriverState *bs, int target_version, |
| BlockDriverAmendStatusCB *status_cb, void *cb_opaque, |
| Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int current_version = s->qcow_version; |
| int ret; |
| int i; |
| |
| /* This is qcow2_downgrade(), not qcow2_upgrade() */ |
| assert(target_version < current_version); |
| |
| /* There are no other versions (now) that you can downgrade to */ |
| assert(target_version == 2); |
| |
| if (s->refcount_order != 4) { |
| error_setg(errp, "compat=0.10 requires refcount_bits=16"); |
| return -ENOTSUP; |
| } |
| |
| if (has_data_file(bs)) { |
| error_setg(errp, "Cannot downgrade an image with a data file"); |
| return -ENOTSUP; |
| } |
| |
| /* |
| * If any internal snapshot has a different size than the current |
| * image size, or VM state size that exceeds 32 bits, downgrading |
| * is unsafe. Even though we would still use v3-compliant output |
| * to preserve that data, other v2 programs might not realize |
| * those optional fields are important. |
| */ |
| for (i = 0; i < s->nb_snapshots; i++) { |
| if (s->snapshots[i].vm_state_size > UINT32_MAX || |
| s->snapshots[i].disk_size != bs->total_sectors * BDRV_SECTOR_SIZE) { |
| error_setg(errp, "Internal snapshots prevent downgrade of image"); |
| return -ENOTSUP; |
| } |
| } |
| |
| /* clear incompatible features */ |
| if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) { |
| ret = qcow2_mark_clean(bs); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to make the image clean"); |
| return ret; |
| } |
| } |
| |
| /* with QCOW2_INCOMPAT_CORRUPT, it is pretty much impossible to get here in |
| * the first place; if that happens nonetheless, returning -ENOTSUP is the |
| * best thing to do anyway */ |
| |
| if (s->incompatible_features) { |
| error_setg(errp, "Cannot downgrade an image with incompatible features " |
| "%#" PRIx64 " set", s->incompatible_features); |
| return -ENOTSUP; |
| } |
| |
| /* since we can ignore compatible features, we can set them to 0 as well */ |
| s->compatible_features = 0; |
| /* if lazy refcounts have been used, they have already been fixed through |
| * clearing the dirty flag */ |
| |
| /* clearing autoclear features is trivial */ |
| s->autoclear_features = 0; |
| |
| ret = qcow2_expand_zero_clusters(bs, status_cb, cb_opaque); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to turn zero into data clusters"); |
| return ret; |
| } |
| |
| s->qcow_version = target_version; |
| ret = qcow2_update_header(bs); |
| if (ret < 0) { |
| s->qcow_version = current_version; |
| error_setg_errno(errp, -ret, "Failed to update the image header"); |
| return ret; |
| } |
| return 0; |
| } |
| |
| /* |
| * Upgrades an image's version. While newer versions encompass all |
| * features of older versions, some things may have to be presented |
| * differently. |
| */ |
| static int qcow2_upgrade(BlockDriverState *bs, int target_version, |
| BlockDriverAmendStatusCB *status_cb, void *cb_opaque, |
| Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| bool need_snapshot_update; |
| int current_version = s->qcow_version; |
| int i; |
| int ret; |
| |
| /* This is qcow2_upgrade(), not qcow2_downgrade() */ |
| assert(target_version > current_version); |
| |
| /* There are no other versions (yet) that you can upgrade to */ |
| assert(target_version == 3); |
| |
| status_cb(bs, 0, 2, cb_opaque); |
| |
| /* |
| * In v2, snapshots do not need to have extra data. v3 requires |
| * the 64-bit VM state size and the virtual disk size to be |
| * present. |
| * qcow2_write_snapshots() will always write the list in the |
| * v3-compliant format. |
| */ |
| need_snapshot_update = false; |
| for (i = 0; i < s->nb_snapshots; i++) { |
| if (s->snapshots[i].extra_data_size < |
| sizeof_field(QCowSnapshotExtraData, vm_state_size_large) + |
| sizeof_field(QCowSnapshotExtraData, disk_size)) |
| { |
| need_snapshot_update = true; |
| break; |
| } |
| } |
| if (need_snapshot_update) { |
| ret = qcow2_write_snapshots(bs); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to update the snapshot table"); |
| return ret; |
| } |
| } |
| status_cb(bs, 1, 2, cb_opaque); |
| |
| s->qcow_version = target_version; |
| ret = qcow2_update_header(bs); |
| if (ret < 0) { |
| s->qcow_version = current_version; |
| error_setg_errno(errp, -ret, "Failed to update the image header"); |
| return ret; |
| } |
| status_cb(bs, 2, 2, cb_opaque); |
| |
| return 0; |
| } |
| |
| typedef enum Qcow2AmendOperation { |
| /* This is the value Qcow2AmendHelperCBInfo::last_operation will be |
| * statically initialized to so that the helper CB can discern the first |
| * invocation from an operation change */ |
| QCOW2_NO_OPERATION = 0, |
| |
| QCOW2_UPGRADING, |
| QCOW2_UPDATING_ENCRYPTION, |
| QCOW2_CHANGING_REFCOUNT_ORDER, |
| QCOW2_DOWNGRADING, |
| } Qcow2AmendOperation; |
| |
| typedef struct Qcow2AmendHelperCBInfo { |
| /* The code coordinating the amend operations should only modify |
| * these four fields; the rest will be managed by the CB */ |
| BlockDriverAmendStatusCB *original_status_cb; |
| void *original_cb_opaque; |
| |
| Qcow2AmendOperation current_operation; |
| |
| /* Total number of operations to perform (only set once) */ |
| int total_operations; |
| |
| /* The following fields are managed by the CB */ |
| |
| /* Number of operations completed */ |
| int operations_completed; |
| |
| /* Cumulative offset of all completed operations */ |
| int64_t offset_completed; |
| |
| Qcow2AmendOperation last_operation; |
| int64_t last_work_size; |
| } Qcow2AmendHelperCBInfo; |
| |
| static void qcow2_amend_helper_cb(BlockDriverState *bs, |
| int64_t operation_offset, |
| int64_t operation_work_size, void *opaque) |
| { |
| Qcow2AmendHelperCBInfo *info = opaque; |
| int64_t current_work_size; |
| int64_t projected_work_size; |
| |
| if (info->current_operation != info->last_operation) { |
| if (info->last_operation != QCOW2_NO_OPERATION) { |
| info->offset_completed += info->last_work_size; |
| info->operations_completed++; |
| } |
| |
| info->last_operation = info->current_operation; |
| } |
| |
| assert(info->total_operations > 0); |
| assert(info->operations_completed < info->total_operations); |
| |
| info->last_work_size = operation_work_size; |
| |
| current_work_size = info->offset_completed + operation_work_size; |
| |
| /* current_work_size is the total work size for (operations_completed + 1) |
| * operations (which includes this one), so multiply it by the number of |
| * operations not covered and divide it by the number of operations |
| * covered to get a projection for the operations not covered */ |
| projected_work_size = current_work_size * (info->total_operations - |
| info->operations_completed - 1) |
| / (info->operations_completed + 1); |
| |
| info->original_status_cb(bs, info->offset_completed + operation_offset, |
| current_work_size + projected_work_size, |
| info->original_cb_opaque); |
| } |
| |
| static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, |
| BlockDriverAmendStatusCB *status_cb, |
| void *cb_opaque, |
| bool force, |
| Error **errp) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| int old_version = s->qcow_version, new_version = old_version; |
| uint64_t new_size = 0; |
| const char *backing_file = NULL, *backing_format = NULL, *data_file = NULL; |
| bool lazy_refcounts = s->use_lazy_refcounts; |
| bool data_file_raw = data_file_is_raw(bs); |
| const char *compat = NULL; |
| int refcount_bits = s->refcount_bits; |
| int ret; |
| QemuOptDesc *desc = opts->list->desc; |
| Qcow2AmendHelperCBInfo helper_cb_info; |
| bool encryption_update = false; |
| |
| while (desc && desc->name) { |
| if (!qemu_opt_find(opts, desc->name)) { |
| /* only change explicitly defined options */ |
| desc++; |
| continue; |
| } |
| |
| if (!strcmp(desc->name, BLOCK_OPT_COMPAT_LEVEL)) { |
| compat = qemu_opt_get(opts, BLOCK_OPT_COMPAT_LEVEL); |
| if (!compat) { |
| /* preserve default */ |
| } else if (!strcmp(compat, "0.10") || !strcmp(compat, "v2")) { |
| new_version = 2; |
| } else if (!strcmp(compat, "1.1") || !strcmp(compat, "v3")) { |
| new_version = 3; |
| } else { |
| error_setg(errp, "Unknown compatibility level %s", compat); |
| return -EINVAL; |
| } |
| } else if (!strcmp(desc->name, BLOCK_OPT_SIZE)) { |
| new_size = qemu_opt_get_size(opts, BLOCK_OPT_SIZE, 0); |
| } else if (!strcmp(desc->name, BLOCK_OPT_BACKING_FILE)) { |
| backing_file = qemu_opt_get(opts, BLOCK_OPT_BACKING_FILE); |
| } else if (!strcmp(desc->name, BLOCK_OPT_BACKING_FMT)) { |
| backing_format = qemu_opt_get(opts, BLOCK_OPT_BACKING_FMT); |
| } else if (g_str_has_prefix(desc->name, "encrypt.")) { |
| if (!s->crypto) { |
| error_setg(errp, |
| "Can't amend encryption options - encryption not present"); |
| return -EINVAL; |
| } |
| if (s->crypt_method_header != QCOW_CRYPT_LUKS) { |
| error_setg(errp, |
| "Only LUKS encryption options can be amended"); |
| return -ENOTSUP; |
| } |
| encryption_update = true; |
| } else if (!strcmp(desc->name, BLOCK_OPT_LAZY_REFCOUNTS)) { |
| lazy_refcounts = qemu_opt_get_bool(opts, BLOCK_OPT_LAZY_REFCOUNTS, |
| lazy_refcounts); |
| } else if (!strcmp(desc->name, BLOCK_OPT_REFCOUNT_BITS)) { |
| refcount_bits = qemu_opt_get_number(opts, BLOCK_OPT_REFCOUNT_BITS, |
| refcount_bits); |
| |
| if (refcount_bits <= 0 || refcount_bits > 64 || |
| !is_power_of_2(refcount_bits)) |
| { |
| error_setg(errp, "Refcount width must be a power of two and " |
| "may not exceed 64 bits"); |
| return -EINVAL; |
| } |
| } else if (!strcmp(desc->name, BLOCK_OPT_DATA_FILE)) { |
| data_file = qemu_opt_get(opts, BLOCK_OPT_DATA_FILE); |
| if (data_file && !has_data_file(bs)) { |
| error_setg(errp, "data-file can only be set for images that " |
| "use an external data file"); |
| return -EINVAL; |
| } |
| } else if (!strcmp(desc->name, BLOCK_OPT_DATA_FILE_RAW)) { |
| data_file_raw = qemu_opt_get_bool(opts, BLOCK_OPT_DATA_FILE_RAW, |
| data_file_raw); |
| if (data_file_raw && !data_file_is_raw(bs)) { |
| error_setg(errp, "data-file-raw cannot be set on existing " |
| "images"); |
| return -EINVAL; |
| } |
| } else { |
| /* if this point is reached, this probably means a new option was |
| * added without having it covered here */ |
| abort(); |
| } |
| |
| desc++; |
| } |
| |
| helper_cb_info = (Qcow2AmendHelperCBInfo){ |
| .original_status_cb = status_cb, |
| .original_cb_opaque = cb_opaque, |
| .total_operations = (new_version != old_version) |
| + (s->refcount_bits != refcount_bits) + |
| (encryption_update == true) |
| }; |
| |
| /* Upgrade first (some features may require compat=1.1) */ |
| if (new_version > old_version) { |
| helper_cb_info.current_operation = QCOW2_UPGRADING; |
| ret = qcow2_upgrade(bs, new_version, &qcow2_amend_helper_cb, |
| &helper_cb_info, errp); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| |
| if (encryption_update) { |
| QDict *amend_opts_dict; |
| QCryptoBlockAmendOptions *amend_opts; |
| |
| helper_cb_info.current_operation = QCOW2_UPDATING_ENCRYPTION; |
| amend_opts_dict = qcow2_extract_crypto_opts(opts, "luks", errp); |
| if (!amend_opts_dict) { |
| return -EINVAL; |
| } |
| amend_opts = block_crypto_amend_opts_init(amend_opts_dict, errp); |
| qobject_unref(amend_opts_dict); |
| if (!amend_opts) { |
| return -EINVAL; |
| } |
| ret = qcrypto_block_amend_options(s->crypto, |
| qcow2_crypto_hdr_read_func, |
| qcow2_crypto_hdr_write_func, |
| bs, |
| amend_opts, |
| force, |
| errp); |
| qapi_free_QCryptoBlockAmendOptions(amend_opts); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| |
| if (s->refcount_bits != refcount_bits) { |
| int refcount_order = ctz32(refcount_bits); |
| |
| if (new_version < 3 && refcount_bits != 16) { |
| error_setg(errp, "Refcount widths other than 16 bits require " |
| "compatibility level 1.1 or above (use compat=1.1 or " |
| "greater)"); |
| return -EINVAL; |
| } |
| |
| helper_cb_info.current_operation = QCOW2_CHANGING_REFCOUNT_ORDER; |
| ret = qcow2_change_refcount_order(bs, refcount_order, |
| &qcow2_amend_helper_cb, |
| &helper_cb_info, errp); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| |
| /* data-file-raw blocks backing files, so clear it first if requested */ |
| if (data_file_raw) { |
| s->autoclear_features |= QCOW2_AUTOCLEAR_DATA_FILE_RAW; |
| } else { |
| s->autoclear_features &= ~QCOW2_AUTOCLEAR_DATA_FILE_RAW; |
| } |
| |
| if (data_file) { |
| g_free(s->image_data_file); |
| s->image_data_file = *data_file ? g_strdup(data_file) : NULL; |
| } |
| |
| ret = qcow2_update_header(bs); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to update the image header"); |
| return ret; |
| } |
| |
| if (backing_file || backing_format) { |
| if (g_strcmp0(backing_file, s->image_backing_file) || |
| g_strcmp0(backing_format, s->image_backing_format)) { |
| warn_report("Deprecated use of amend to alter the backing file; " |
| "use qemu-img rebase instead"); |
| } |
| ret = qcow2_change_backing_file(bs, |
| backing_file ?: s->image_backing_file, |
| backing_format ?: s->image_backing_format); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to change the backing file"); |
| return ret; |
| } |
| } |
| |
| if (s->use_lazy_refcounts != lazy_refcounts) { |
| if (lazy_refcounts) { |
| if (new_version < 3) { |
| error_setg(errp, "Lazy refcounts only supported with " |
| "compatibility level 1.1 and above (use compat=1.1 " |
| "or greater)"); |
| return -EINVAL; |
| } |
| s->compatible_features |= QCOW2_COMPAT_LAZY_REFCOUNTS; |
| ret = qcow2_update_header(bs); |
| if (ret < 0) { |
| s->compatible_features &= ~QCOW2_COMPAT_LAZY_REFCOUNTS; |
| error_setg_errno(errp, -ret, "Failed to update the image header"); |
| return ret; |
| } |
| s->use_lazy_refcounts = true; |
| } else { |
| /* make image clean first */ |
| ret = qcow2_mark_clean(bs); |
| if (ret < 0) { |
| error_setg_errno(errp, -ret, "Failed to make the image clean"); |
| return ret; |
| } |
| /* now disallow lazy refcounts */ |
| s->compatible_features &= ~QCOW2_COMPAT_LAZY_REFCOUNTS; |
| ret = qcow2_update_header(bs); |
| if (ret < 0) { |
| s->compatible_features |= QCOW2_COMPAT_LAZY_REFCOUNTS; |
| error_setg_errno(errp, -ret, "Failed to update the image header"); |
| return ret; |
| } |
| s->use_lazy_refcounts = false; |
| } |
| } |
| |
| if (new_size) { |
| BlockBackend *blk = blk_new_with_bs(bs, BLK_PERM_RESIZE, BLK_PERM_ALL, |
| errp); |
| if (!blk) { |
| return -EPERM; |
| } |
| |
| /* |
| * Amending image options should ensure that the image has |
| * exactly the given new values, so pass exact=true here. |
| */ |
| ret = blk_truncate(blk, new_size, true, PREALLOC_MODE_OFF, 0, errp); |
| blk_unref(blk); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| |
| /* Downgrade last (so unsupported features can be removed before) */ |
| if (new_version < old_version) { |
| helper_cb_info.current_operation = QCOW2_DOWNGRADING; |
| ret = qcow2_downgrade(bs, new_version, &qcow2_amend_helper_cb, |
| &helper_cb_info, errp); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int coroutine_fn qcow2_co_amend(BlockDriverState *bs, |
| BlockdevAmendOptions *opts, |
| bool force, |
| Error **errp) |
| { |
| BlockdevAmendOptionsQcow2 *qopts = &opts->u.qcow2; |
| BDRVQcow2State *s = bs->opaque; |
| int ret = 0; |
| |
| if (qopts->has_encrypt) { |
| if (!s->crypto) { |
| error_setg(errp, "image is not encrypted, can't amend"); |
| return -EOPNOTSUPP; |
| } |
| |
| if (qopts->encrypt->format != Q_CRYPTO_BLOCK_FORMAT_LUKS) { |
| error_setg(errp, |
| "Amend can't be used to change the qcow2 encryption format"); |
| return -EOPNOTSUPP; |
| } |
| |
| if (s->crypt_method_header != QCOW_CRYPT_LUKS) { |
| error_setg(errp, |
| "Only LUKS encryption options can be amended for qcow2 with blockdev-amend"); |
| return -EOPNOTSUPP; |
| } |
| |
| ret = qcrypto_block_amend_options(s->crypto, |
| qcow2_crypto_hdr_read_func, |
| qcow2_crypto_hdr_write_func, |
| bs, |
| qopts->encrypt, |
| force, |
| errp); |
| } |
| return ret; |
| } |
| |
| /* |
| * If offset or size are negative, respectively, they will not be included in |
| * the BLOCK_IMAGE_CORRUPTED event emitted. |
| * fatal will be ignored for read-only BDS; corruptions found there will always |
| * be considered non-fatal. |
| */ |
| void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset, |
| int64_t size, const char *message_format, ...) |
| { |
| BDRVQcow2State *s = bs->opaque; |
| const char *node_name; |
| char *message; |
| va_list ap; |
| |
| fatal = fatal && bdrv_is_writable(bs); |
| |
| if (s->signaled_corruption && |
| (!fatal || (s->incompatible_features & QCOW2_INCOMPAT_CORRUPT))) |
| { |
| return; |
| } |
| |
| va_start(ap, message_format); |
| message = g_strdup_vprintf(message_format, ap); |
| va_end(ap); |
| |
| if (fatal) { |
| fprintf(stderr, "qcow2: Marking image as corrupt: %s; further " |
| "corruption events will be suppressed\n", message); |
| } else { |
| fprintf(stderr, "qcow2: Image is corrupt: %s; further non-fatal " |
| "corruption events will be suppressed\n", message); |
| } |
| |
| node_name = bdrv_get_node_name(bs); |
| qapi_event_send_block_image_corrupted(bdrv_get_device_name(bs), |
| *node_name != '\0', node_name, |
| message, offset >= 0, offset, |
| size >= 0, size, |
| fatal); |
| g_free(message); |
| |
| if (fatal) { |
| qcow2_mark_corrupt(bs); |
| bs->drv = NULL; /* make BDS unusable */ |
| } |
| |
| s->signaled_corruption = true; |
| } |
| |
| #define QCOW_COMMON_OPTIONS \ |
| { \ |
| .name = BLOCK_OPT_SIZE, \ |
| .type = QEMU_OPT_SIZE, \ |
| .help = "Virtual disk size" \ |
| }, \ |
| { \ |
| .name = BLOCK_OPT_COMPAT_LEVEL, \ |
| .type = QEMU_OPT_STRING, \ |
| .help = "Compatibility level (v2 [0.10] or v3 [1.1])" \ |
| }, \ |
| { \ |
| .name = BLOCK_OPT_BACKING_FILE, \ |
| .type = QEMU_OPT_STRING, \ |
| .help = "File name of a base image" \ |
| }, \ |
| { \ |
| .name = BLOCK_OPT_BACKING_FMT, \ |
| .type = QEMU_OPT_STRING, \ |
| .help = "Image format of the base image" \ |
| }, \ |
| { \ |
| .name = BLOCK_OPT_DATA_FILE, \ |
| .type = QEMU_OPT_STRING, \ |
| .help = "File name of an external data file" \ |
| }, \ |
| { \ |
| .name = BLOCK_OPT_DATA_FILE_RAW, \ |
| .type = QEMU_OPT_BOOL, \ |
| .help = "The external data file must stay valid " \ |
| "as a raw image" \ |
| }, \ |
| { \ |
| .name = BLOCK_OPT_LAZY_REFCOUNTS, \ |
| .type = QEMU_OPT_BOOL, \ |
| .help = "Postpone refcount updates", \ |
| .def_value_str = "off" \ |
| }, \ |
| { \ |
| .name = BLOCK_OPT_REFCOUNT_BITS, \ |
| .type = QEMU_OPT_NUMBER, \ |
| .help = "Width of a reference count entry in bits", \ |
| .def_value_str = "16" \ |
| } |
| |
| static QemuOptsList qcow2_create_opts = { |
| .name = "qcow2-create-opts", |
| .head = QTAILQ_HEAD_INITIALIZER(qcow2_create_opts.head), |
| .desc = { |
| { \ |
| .name = BLOCK_OPT_ENCRYPT, \ |
| .type = QEMU_OPT_BOOL, \ |
| .help = "Encrypt the image with format 'aes'. (Deprecated " \ |
| "in favor of " BLOCK_OPT_ENCRYPT_FORMAT "=aes)", \ |
| }, \ |
| { \ |
| .name = BLOCK_OPT_ENCRYPT_FORMAT, \ |
| .type = QEMU_OPT_STRING, \ |
| .help = "Encrypt the image, format choices: 'aes', 'luks'", \ |
| }, \ |
| BLOCK_CRYPTO_OPT_DEF_KEY_SECRET("encrypt.", \ |
| "ID of secret providing qcow AES key or LUKS passphrase"), \ |
| BLOCK_CRYPTO_OPT_DEF_LUKS_CIPHER_ALG("encrypt."), \ |
| BLOCK_CRYPTO_OPT_DEF_LUKS_CIPHER_MODE("encrypt."), \ |
| BLOCK_CRYPTO_OPT_DEF_LUKS_IVGEN_ALG("encrypt."), \ |
| BLOCK_CRYPTO_OPT_DEF_LUKS_IVGEN_HASH_ALG("encrypt."), \ |
| BLOCK_CRYPTO_OPT_DEF_LUKS_HASH_ALG("encrypt."), \ |
| BLOCK_CRYPTO_OPT_DEF_LUKS_ITER_TIME("encrypt."), \ |
| { \ |
| .name = BLOCK_OPT_CLUSTER_SIZE, \ |
| .type = QEMU_OPT_SIZE, \ |
| .help = "qcow2 cluster size", \ |
| .def_value_str = stringify(DEFAULT_CLUSTER_SIZE) \ |
| }, \ |
| { \ |
| .name = BLOCK_OPT_EXTL2, \ |
| .type = QEMU_OPT_BOOL, \ |
| .help = "Extended L2 tables", \ |
| .def_value_str = "off" \ |
| }, \ |
| { \ |
| .name = BLOCK_OPT_PREALLOC, \ |
| .type = QEMU_OPT_STRING, \ |
| .help = "Preallocation mode (allowed values: off, " \ |
| "metadata, falloc, full)" \ |
| }, \ |
| { \ |
| .name = BLOCK_OPT_COMPRESSION_TYPE, \ |
| .type = QEMU_OPT_STRING, \ |
| .help = "Compression method used for image cluster " \ |
| "compression", \ |
| .def_value_str = "zlib" \ |
| }, |
| QCOW_COMMON_OPTIONS, |
| { /* end of list */ } |
| } |
| }; |
| |
| static QemuOptsList qcow2_amend_opts = { |
| .name = "qcow2-amend-opts", |
| .head = QTAILQ_HEAD_INITIALIZER(qcow2_amend_opts.head), |
| .desc = { |
| BLOCK_CRYPTO_OPT_DEF_LUKS_STATE("encrypt."), |
| BLOCK_CRYPTO_OPT_DEF_LUKS_KEYSLOT("encrypt."), |
| BLOCK_CRYPTO_OPT_DEF_LUKS_OLD_SECRET("encrypt."), |
| BLOCK_CRYPTO_OPT_DEF_LUKS_NEW_SECRET("encrypt."), |
| BLOCK_CRYPTO_OPT_DEF_LUKS_ITER_TIME("encrypt."), |
| QCOW_COMMON_OPTIONS, |
| { /* end of list */ } |
| } |
| }; |
| |
| static const char *const qcow2_strong_runtime_opts[] = { |
| "encrypt." BLOCK_CRYPTO_OPT_QCOW_KEY_SECRET, |
| |
| NULL |
| }; |
| |
| BlockDriver bdrv_qcow2 = { |
| .format_name = "qcow2", |
| .instance_size = sizeof(BDRVQcow2State), |
| .bdrv_probe = qcow2_probe, |
| .bdrv_open = qcow2_open, |
| .bdrv_close = qcow2_close, |
| .bdrv_reopen_prepare = qcow2_reopen_prepare, |
| .bdrv_reopen_commit = qcow2_reopen_commit, |
| .bdrv_reopen_commit_post = qcow2_reopen_commit_post, |
| .bdrv_reopen_abort = qcow2_reopen_abort, |
| .bdrv_join_options = qcow2_join_options, |
| .bdrv_child_perm = bdrv_default_perms, |
| .bdrv_co_create_opts = qcow2_co_create_opts, |
| .bdrv_co_create = qcow2_co_create, |
| .bdrv_has_zero_init = qcow2_has_zero_init, |
| .bdrv_co_block_status = qcow2_co_block_status, |
| |
| .bdrv_co_preadv_part = qcow2_co_preadv_part, |
| .bdrv_co_pwritev_part = qcow2_co_pwritev_part, |
| .bdrv_co_flush_to_os = qcow2_co_flush_to_os, |
| |
| .bdrv_co_pwrite_zeroes = qcow2_co_pwrite_zeroes, |
| .bdrv_co_pdiscard = qcow2_co_pdiscard, |
| .bdrv_co_copy_range_from = qcow2_co_copy_range_from, |
| .bdrv_co_copy_range_to = qcow2_co_copy_range_to, |
| .bdrv_co_truncate = qcow2_co_truncate, |
| .bdrv_co_pwritev_compressed_part = qcow2_co_pwritev_compressed_part, |
| .bdrv_make_empty = qcow2_make_empty, |
| |
| .bdrv_snapshot_create = qcow2_snapshot_create, |
| .bdrv_snapshot_goto = qcow2_snapshot_goto, |
| .bdrv_snapshot_delete = qcow2_snapshot_delete, |
| .bdrv_snapshot_list = qcow2_snapshot_list, |
| .bdrv_snapshot_load_tmp = qcow2_snapshot_load_tmp, |
| .bdrv_measure = qcow2_measure, |
| .bdrv_get_info = qcow2_get_info, |
| .bdrv_get_specific_info = qcow2_get_specific_info, |
| |
| .bdrv_save_vmstate = qcow2_save_vmstate, |
| .bdrv_load_vmstate = qcow2_load_vmstate, |
| |
| .is_format = true, |
| .supports_backing = true, |
| .bdrv_change_backing_file = qcow2_change_backing_file, |
| |
| .bdrv_refresh_limits = qcow2_refresh_limits, |
| .bdrv_co_invalidate_cache = qcow2_co_invalidate_cache, |
| .bdrv_inactivate = qcow2_inactivate, |
| |
| .create_opts = &qcow2_create_opts, |
| .amend_opts = &qcow2_amend_opts, |
| .strong_runtime_opts = qcow2_strong_runtime_opts, |
| .mutable_opts = mutable_opts, |
| .bdrv_co_check = qcow2_co_check, |
| .bdrv_amend_options = qcow2_amend_options, |
| .bdrv_co_amend = qcow2_co_amend, |
| |
| .bdrv_detach_aio_context = qcow2_detach_aio_context, |
| .bdrv_attach_aio_context = qcow2_attach_aio_context, |
| |
| .bdrv_supports_persistent_dirty_bitmap = |
| qcow2_supports_persistent_dirty_bitmap, |
| .bdrv_co_can_store_new_dirty_bitmap = qcow2_co_can_store_new_dirty_bitmap, |
| .bdrv_co_remove_persistent_dirty_bitmap = |
| qcow2_co_remove_persistent_dirty_bitmap, |
| }; |
| |
| static void bdrv_qcow2_init(void) |
| { |
| bdrv_register(&bdrv_qcow2); |
| } |
| |
| block_init(bdrv_qcow2_init); |