| /* |
| * Block driver for the QCOW 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 "qapi/error.h" |
| #include "qemu/error-report.h" |
| #include "block/block_int.h" |
| #include "block/qdict.h" |
| #include "sysemu/block-backend.h" |
| #include "qemu/module.h" |
| #include "qemu/option.h" |
| #include "qemu/bswap.h" |
| #include "qemu/cutils.h" |
| #include <zlib.h> |
| #include "qapi/qmp/qdict.h" |
| #include "qapi/qmp/qstring.h" |
| #include "qapi/qobject-input-visitor.h" |
| #include "qapi/qapi-visit-block-core.h" |
| #include "crypto/block.h" |
| #include "migration/blocker.h" |
| #include "crypto.h" |
| |
| /**************************************************************/ |
| /* QEMU COW block driver with compression and encryption support */ |
| |
| #define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb) |
| #define QCOW_VERSION 1 |
| |
| #define QCOW_CRYPT_NONE 0 |
| #define QCOW_CRYPT_AES 1 |
| |
| #define QCOW_OFLAG_COMPRESSED (1LL << 63) |
| |
| typedef struct QCowHeader { |
| uint32_t magic; |
| uint32_t version; |
| uint64_t backing_file_offset; |
| uint32_t backing_file_size; |
| uint32_t mtime; |
| uint64_t size; /* in bytes */ |
| uint8_t cluster_bits; |
| uint8_t l2_bits; |
| uint16_t padding; |
| uint32_t crypt_method; |
| uint64_t l1_table_offset; |
| } QEMU_PACKED QCowHeader; |
| |
| #define L2_CACHE_SIZE 16 |
| |
| typedef struct BDRVQcowState { |
| int cluster_bits; |
| int cluster_size; |
| int l2_bits; |
| int l2_size; |
| unsigned int l1_size; |
| uint64_t cluster_offset_mask; |
| uint64_t l1_table_offset; |
| uint64_t *l1_table; |
| uint64_t *l2_cache; |
| uint64_t l2_cache_offsets[L2_CACHE_SIZE]; |
| uint32_t l2_cache_counts[L2_CACHE_SIZE]; |
| uint8_t *cluster_cache; |
| uint8_t *cluster_data; |
| uint64_t cluster_cache_offset; |
| QCryptoBlock *crypto; /* Disk encryption format driver */ |
| uint32_t crypt_method_header; |
| CoMutex lock; |
| Error *migration_blocker; |
| } BDRVQcowState; |
| |
| static QemuOptsList qcow_create_opts; |
| |
| static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset); |
| |
| static int qcow_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) == QCOW_VERSION) |
| return 100; |
| else |
| return 0; |
| } |
| |
| static QemuOptsList qcow_runtime_opts = { |
| .name = "qcow", |
| .head = QTAILQ_HEAD_INITIALIZER(qcow_runtime_opts.head), |
| .desc = { |
| BLOCK_CRYPTO_OPT_DEF_QCOW_KEY_SECRET("encrypt."), |
| { /* end of list */ } |
| }, |
| }; |
| |
| static int qcow_open(BlockDriverState *bs, QDict *options, int flags, |
| Error **errp) |
| { |
| BDRVQcowState *s = bs->opaque; |
| unsigned int len, i, shift; |
| int ret; |
| QCowHeader header; |
| Error *local_err = NULL; |
| QCryptoBlockOpenOptions *crypto_opts = NULL; |
| unsigned int cflags = 0; |
| QDict *encryptopts = NULL; |
| const char *encryptfmt; |
| |
| qdict_extract_subqdict(options, &encryptopts, "encrypt."); |
| encryptfmt = qdict_get_try_str(encryptopts, "format"); |
| |
| bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, |
| false, errp); |
| if (!bs->file) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| ret = bdrv_pread(bs->file, 0, &header, sizeof(header)); |
| if (ret < 0) { |
| 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.mtime = be32_to_cpu(header.mtime); |
| header.size = be64_to_cpu(header.size); |
| header.crypt_method = be32_to_cpu(header.crypt_method); |
| header.l1_table_offset = be64_to_cpu(header.l1_table_offset); |
| |
| if (header.magic != QCOW_MAGIC) { |
| error_setg(errp, "Image not in qcow format"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| if (header.version != QCOW_VERSION) { |
| error_setg(errp, "qcow (v%d) does not support qcow version %" PRIu32, |
| QCOW_VERSION, header.version); |
| if (header.version == 2 || header.version == 3) { |
| error_append_hint(errp, "Try the 'qcow2' driver instead.\n"); |
| } |
| |
| ret = -ENOTSUP; |
| goto fail; |
| } |
| |
| if (header.size <= 1) { |
| error_setg(errp, "Image size is too small (must be at least 2 bytes)"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| if (header.cluster_bits < 9 || header.cluster_bits > 16) { |
| error_setg(errp, "Cluster size must be between 512 and 64k"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* l2_bits specifies number of entries; storing a uint64_t in each entry, |
| * so bytes = num_entries << 3. */ |
| if (header.l2_bits < 9 - 3 || header.l2_bits > 16 - 3) { |
| error_setg(errp, "L2 table size must be between 512 and 64k"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| 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 qcow 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 qcow, or raw with the LUKS " |
| "format instead.\n"); |
| ret = -ENOSYS; |
| goto fail; |
| } |
| if (s->crypt_method_header == 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"); |
| crypto_opts = block_crypto_open_opts_init(encryptopts, errp); |
| if (!crypto_opts) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| if (flags & BDRV_O_NO_IO) { |
| cflags |= QCRYPTO_BLOCK_OPEN_NO_IO; |
| } |
| s->crypto = qcrypto_block_open(crypto_opts, "encrypt.", |
| NULL, NULL, cflags, 1, errp); |
| if (!s->crypto) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| } else { |
| error_setg(errp, "invalid encryption method in qcow header"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| bs->encrypted = true; |
| } else { |
| if (encryptfmt) { |
| error_setg(errp, "No encryption in image header, but options " |
| "specified format '%s'", encryptfmt); |
| ret = -EINVAL; |
| goto fail; |
| } |
| } |
| s->cluster_bits = header.cluster_bits; |
| s->cluster_size = 1 << s->cluster_bits; |
| s->l2_bits = header.l2_bits; |
| s->l2_size = 1 << s->l2_bits; |
| bs->total_sectors = header.size / 512; |
| s->cluster_offset_mask = (1LL << (63 - s->cluster_bits)) - 1; |
| |
| /* read the level 1 table */ |
| shift = s->cluster_bits + s->l2_bits; |
| if (header.size > UINT64_MAX - (1LL << shift)) { |
| error_setg(errp, "Image too large"); |
| ret = -EINVAL; |
| goto fail; |
| } else { |
| uint64_t l1_size = (header.size + (1LL << shift) - 1) >> shift; |
| if (l1_size > INT_MAX / sizeof(uint64_t)) { |
| error_setg(errp, "Image too large"); |
| ret = -EINVAL; |
| goto fail; |
| } |
| s->l1_size = l1_size; |
| } |
| |
| s->l1_table_offset = header.l1_table_offset; |
| s->l1_table = g_try_new(uint64_t, s->l1_size); |
| if (s->l1_table == NULL) { |
| error_setg(errp, "Could not allocate memory for L1 table"); |
| ret = -ENOMEM; |
| goto fail; |
| } |
| |
| ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table, |
| s->l1_size * sizeof(uint64_t)); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| for(i = 0;i < s->l1_size; i++) { |
| s->l1_table[i] = be64_to_cpu(s->l1_table[i]); |
| } |
| |
| /* alloc L2 cache (max. 64k * 16 * 8 = 8 MB) */ |
| s->l2_cache = |
| qemu_try_blockalign(bs->file->bs, |
| s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); |
| if (s->l2_cache == NULL) { |
| error_setg(errp, "Could not allocate L2 table cache"); |
| ret = -ENOMEM; |
| goto fail; |
| } |
| s->cluster_cache = g_malloc(s->cluster_size); |
| s->cluster_data = g_malloc(s->cluster_size); |
| s->cluster_cache_offset = -1; |
| |
| /* read the backing file name */ |
| if (header.backing_file_offset != 0) { |
| len = header.backing_file_size; |
| if (len > 1023 || 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) { |
| goto fail; |
| } |
| bs->auto_backing_file[len] = '\0'; |
| pstrcpy(bs->backing_file, sizeof(bs->backing_file), |
| bs->auto_backing_file); |
| } |
| |
| /* Disable migration when qcow images are used */ |
| error_setg(&s->migration_blocker, "The qcow format used by node '%s' " |
| "does not support live migration", |
| bdrv_get_device_or_node_name(bs)); |
| ret = migrate_add_blocker(s->migration_blocker, &local_err); |
| if (local_err) { |
| error_propagate(errp, local_err); |
| error_free(s->migration_blocker); |
| goto fail; |
| } |
| |
| qobject_unref(encryptopts); |
| qapi_free_QCryptoBlockOpenOptions(crypto_opts); |
| qemu_co_mutex_init(&s->lock); |
| return 0; |
| |
| fail: |
| g_free(s->l1_table); |
| qemu_vfree(s->l2_cache); |
| g_free(s->cluster_cache); |
| g_free(s->cluster_data); |
| qcrypto_block_free(s->crypto); |
| qobject_unref(encryptopts); |
| qapi_free_QCryptoBlockOpenOptions(crypto_opts); |
| return ret; |
| } |
| |
| |
| /* We have nothing to do for QCOW reopen, stubs just return |
| * success */ |
| static int qcow_reopen_prepare(BDRVReopenState *state, |
| BlockReopenQueue *queue, Error **errp) |
| { |
| return 0; |
| } |
| |
| |
| /* 'allocate' is: |
| * |
| * 0 to not allocate. |
| * |
| * 1 to allocate a normal cluster (for sector-aligned byte offsets 'n_start' |
| * to 'n_end' within the cluster) |
| * |
| * 2 to allocate a compressed cluster of size |
| * 'compressed_size'. 'compressed_size' must be > 0 and < |
| * cluster_size |
| * |
| * return 0 if not allocated, 1 if *result is assigned, and negative |
| * errno on failure. |
| */ |
| static int get_cluster_offset(BlockDriverState *bs, |
| uint64_t offset, int allocate, |
| int compressed_size, |
| int n_start, int n_end, uint64_t *result) |
| { |
| BDRVQcowState *s = bs->opaque; |
| int min_index, i, j, l1_index, l2_index, ret; |
| int64_t l2_offset; |
| uint64_t *l2_table, cluster_offset, tmp; |
| uint32_t min_count; |
| int new_l2_table; |
| |
| *result = 0; |
| l1_index = offset >> (s->l2_bits + s->cluster_bits); |
| l2_offset = s->l1_table[l1_index]; |
| new_l2_table = 0; |
| if (!l2_offset) { |
| if (!allocate) |
| return 0; |
| /* allocate a new l2 entry */ |
| l2_offset = bdrv_getlength(bs->file->bs); |
| if (l2_offset < 0) { |
| return l2_offset; |
| } |
| /* round to cluster size */ |
| l2_offset = QEMU_ALIGN_UP(l2_offset, s->cluster_size); |
| /* update the L1 entry */ |
| s->l1_table[l1_index] = l2_offset; |
| tmp = cpu_to_be64(l2_offset); |
| BLKDBG_EVENT(bs->file, BLKDBG_L1_UPDATE); |
| ret = bdrv_pwrite_sync(bs->file, |
| s->l1_table_offset + l1_index * sizeof(tmp), |
| &tmp, sizeof(tmp)); |
| if (ret < 0) { |
| return ret; |
| } |
| new_l2_table = 1; |
| } |
| for(i = 0; i < L2_CACHE_SIZE; i++) { |
| if (l2_offset == s->l2_cache_offsets[i]) { |
| /* increment the hit count */ |
| if (++s->l2_cache_counts[i] == 0xffffffff) { |
| for(j = 0; j < L2_CACHE_SIZE; j++) { |
| s->l2_cache_counts[j] >>= 1; |
| } |
| } |
| l2_table = s->l2_cache + (i << s->l2_bits); |
| goto found; |
| } |
| } |
| /* not found: load a new entry in the least used one */ |
| min_index = 0; |
| min_count = 0xffffffff; |
| for(i = 0; i < L2_CACHE_SIZE; i++) { |
| if (s->l2_cache_counts[i] < min_count) { |
| min_count = s->l2_cache_counts[i]; |
| min_index = i; |
| } |
| } |
| l2_table = s->l2_cache + (min_index << s->l2_bits); |
| BLKDBG_EVENT(bs->file, BLKDBG_L2_LOAD); |
| if (new_l2_table) { |
| memset(l2_table, 0, s->l2_size * sizeof(uint64_t)); |
| ret = bdrv_pwrite_sync(bs->file, l2_offset, l2_table, |
| s->l2_size * sizeof(uint64_t)); |
| if (ret < 0) { |
| return ret; |
| } |
| } else { |
| ret = bdrv_pread(bs->file, l2_offset, l2_table, |
| s->l2_size * sizeof(uint64_t)); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| s->l2_cache_offsets[min_index] = l2_offset; |
| s->l2_cache_counts[min_index] = 1; |
| found: |
| l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1); |
| cluster_offset = be64_to_cpu(l2_table[l2_index]); |
| if (!cluster_offset || |
| ((cluster_offset & QCOW_OFLAG_COMPRESSED) && allocate == 1)) { |
| if (!allocate) |
| return 0; |
| BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC); |
| assert(QEMU_IS_ALIGNED(n_start | n_end, BDRV_SECTOR_SIZE)); |
| /* allocate a new cluster */ |
| if ((cluster_offset & QCOW_OFLAG_COMPRESSED) && |
| (n_end - n_start) < s->cluster_size) { |
| /* if the cluster is already compressed, we must |
| decompress it in the case it is not completely |
| overwritten */ |
| if (decompress_cluster(bs, cluster_offset) < 0) { |
| return -EIO; |
| } |
| cluster_offset = bdrv_getlength(bs->file->bs); |
| if ((int64_t) cluster_offset < 0) { |
| return cluster_offset; |
| } |
| cluster_offset = QEMU_ALIGN_UP(cluster_offset, s->cluster_size); |
| /* write the cluster content */ |
| BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO); |
| ret = bdrv_pwrite(bs->file, cluster_offset, s->cluster_cache, |
| s->cluster_size); |
| if (ret < 0) { |
| return ret; |
| } |
| } else { |
| cluster_offset = bdrv_getlength(bs->file->bs); |
| if ((int64_t) cluster_offset < 0) { |
| return cluster_offset; |
| } |
| if (allocate == 1) { |
| /* round to cluster size */ |
| cluster_offset = QEMU_ALIGN_UP(cluster_offset, s->cluster_size); |
| if (cluster_offset + s->cluster_size > INT64_MAX) { |
| return -E2BIG; |
| } |
| ret = bdrv_truncate(bs->file, cluster_offset + s->cluster_size, |
| PREALLOC_MODE_OFF, NULL); |
| if (ret < 0) { |
| return ret; |
| } |
| /* if encrypted, we must initialize the cluster |
| content which won't be written */ |
| if (bs->encrypted && |
| (n_end - n_start) < s->cluster_size) { |
| uint64_t start_offset; |
| assert(s->crypto); |
| start_offset = offset & ~(s->cluster_size - 1); |
| for (i = 0; i < s->cluster_size; i += BDRV_SECTOR_SIZE) { |
| if (i < n_start || i >= n_end) { |
| memset(s->cluster_data, 0x00, BDRV_SECTOR_SIZE); |
| if (qcrypto_block_encrypt(s->crypto, |
| start_offset + i, |
| s->cluster_data, |
| BDRV_SECTOR_SIZE, |
| NULL) < 0) { |
| return -EIO; |
| } |
| BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO); |
| ret = bdrv_pwrite(bs->file, |
| cluster_offset + i, |
| s->cluster_data, |
| BDRV_SECTOR_SIZE); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| } |
| } |
| } else if (allocate == 2) { |
| cluster_offset |= QCOW_OFLAG_COMPRESSED | |
| (uint64_t)compressed_size << (63 - s->cluster_bits); |
| } |
| } |
| /* update L2 table */ |
| tmp = cpu_to_be64(cluster_offset); |
| l2_table[l2_index] = tmp; |
| if (allocate == 2) { |
| BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE_COMPRESSED); |
| } else { |
| BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE); |
| } |
| ret = bdrv_pwrite_sync(bs->file, l2_offset + l2_index * sizeof(tmp), |
| &tmp, sizeof(tmp)); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| *result = cluster_offset; |
| return 1; |
| } |
| |
| static int coroutine_fn qcow_co_block_status(BlockDriverState *bs, |
| bool want_zero, |
| int64_t offset, int64_t bytes, |
| int64_t *pnum, int64_t *map, |
| BlockDriverState **file) |
| { |
| BDRVQcowState *s = bs->opaque; |
| int index_in_cluster, ret; |
| int64_t n; |
| uint64_t cluster_offset; |
| |
| qemu_co_mutex_lock(&s->lock); |
| ret = get_cluster_offset(bs, offset, 0, 0, 0, 0, &cluster_offset); |
| qemu_co_mutex_unlock(&s->lock); |
| if (ret < 0) { |
| return ret; |
| } |
| index_in_cluster = offset & (s->cluster_size - 1); |
| n = s->cluster_size - index_in_cluster; |
| if (n > bytes) { |
| n = bytes; |
| } |
| *pnum = n; |
| if (!cluster_offset) { |
| return 0; |
| } |
| if ((cluster_offset & QCOW_OFLAG_COMPRESSED) || s->crypto) { |
| return BDRV_BLOCK_DATA; |
| } |
| *map = cluster_offset | index_in_cluster; |
| *file = bs->file->bs; |
| return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; |
| } |
| |
| static int decompress_buffer(uint8_t *out_buf, int out_buf_size, |
| const uint8_t *buf, int buf_size) |
| { |
| z_stream strm1, *strm = &strm1; |
| int ret, out_len; |
| |
| memset(strm, 0, sizeof(*strm)); |
| |
| strm->next_in = (uint8_t *)buf; |
| strm->avail_in = buf_size; |
| strm->next_out = out_buf; |
| strm->avail_out = out_buf_size; |
| |
| ret = inflateInit2(strm, -12); |
| if (ret != Z_OK) |
| return -1; |
| ret = inflate(strm, Z_FINISH); |
| out_len = strm->next_out - out_buf; |
| if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) || |
| out_len != out_buf_size) { |
| inflateEnd(strm); |
| return -1; |
| } |
| inflateEnd(strm); |
| return 0; |
| } |
| |
| static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset) |
| { |
| BDRVQcowState *s = bs->opaque; |
| int ret, csize; |
| uint64_t coffset; |
| |
| coffset = cluster_offset & s->cluster_offset_mask; |
| if (s->cluster_cache_offset != coffset) { |
| csize = cluster_offset >> (63 - s->cluster_bits); |
| csize &= (s->cluster_size - 1); |
| BLKDBG_EVENT(bs->file, BLKDBG_READ_COMPRESSED); |
| ret = bdrv_pread(bs->file, coffset, s->cluster_data, csize); |
| if (ret != csize) |
| return -1; |
| if (decompress_buffer(s->cluster_cache, s->cluster_size, |
| s->cluster_data, csize) < 0) { |
| return -1; |
| } |
| s->cluster_cache_offset = coffset; |
| } |
| return 0; |
| } |
| |
| static void qcow_refresh_limits(BlockDriverState *bs, Error **errp) |
| { |
| /* At least encrypted images require 512-byte alignment. Apply the |
| * limit universally, rather than just on encrypted images, as |
| * it's easier to let the block layer handle rounding than to |
| * audit this code further. */ |
| bs->bl.request_alignment = BDRV_SECTOR_SIZE; |
| } |
| |
| static coroutine_fn int qcow_co_preadv(BlockDriverState *bs, uint64_t offset, |
| uint64_t bytes, QEMUIOVector *qiov, |
| int flags) |
| { |
| BDRVQcowState *s = bs->opaque; |
| int offset_in_cluster; |
| int ret = 0, n; |
| uint64_t cluster_offset; |
| uint8_t *buf; |
| void *orig_buf; |
| |
| assert(!flags); |
| if (qiov->niov > 1) { |
| buf = orig_buf = qemu_try_blockalign(bs, qiov->size); |
| if (buf == NULL) { |
| return -ENOMEM; |
| } |
| } else { |
| orig_buf = NULL; |
| buf = (uint8_t *)qiov->iov->iov_base; |
| } |
| |
| qemu_co_mutex_lock(&s->lock); |
| |
| while (bytes != 0) { |
| /* prepare next request */ |
| ret = get_cluster_offset(bs, offset, 0, 0, 0, 0, &cluster_offset); |
| if (ret < 0) { |
| break; |
| } |
| offset_in_cluster = offset & (s->cluster_size - 1); |
| n = s->cluster_size - offset_in_cluster; |
| if (n > bytes) { |
| n = bytes; |
| } |
| |
| if (!cluster_offset) { |
| if (bs->backing) { |
| /* read from the base image */ |
| qemu_co_mutex_unlock(&s->lock); |
| /* qcow2 emits this on bs->file instead of bs->backing */ |
| BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO); |
| ret = bdrv_co_pread(bs->backing, offset, n, buf, 0); |
| qemu_co_mutex_lock(&s->lock); |
| if (ret < 0) { |
| break; |
| } |
| } else { |
| /* Note: in this case, no need to wait */ |
| memset(buf, 0, n); |
| } |
| } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) { |
| /* add AIO support for compressed blocks ? */ |
| if (decompress_cluster(bs, cluster_offset) < 0) { |
| ret = -EIO; |
| break; |
| } |
| memcpy(buf, s->cluster_cache + offset_in_cluster, n); |
| } else { |
| if ((cluster_offset & 511) != 0) { |
| ret = -EIO; |
| break; |
| } |
| qemu_co_mutex_unlock(&s->lock); |
| BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); |
| ret = bdrv_co_pread(bs->file, cluster_offset + offset_in_cluster, |
| n, buf, 0); |
| qemu_co_mutex_lock(&s->lock); |
| if (ret < 0) { |
| break; |
| } |
| if (bs->encrypted) { |
| assert(s->crypto); |
| if (qcrypto_block_decrypt(s->crypto, |
| offset, buf, n, NULL) < 0) { |
| ret = -EIO; |
| break; |
| } |
| } |
| } |
| ret = 0; |
| |
| bytes -= n; |
| offset += n; |
| buf += n; |
| } |
| |
| qemu_co_mutex_unlock(&s->lock); |
| |
| if (qiov->niov > 1) { |
| qemu_iovec_from_buf(qiov, 0, orig_buf, qiov->size); |
| qemu_vfree(orig_buf); |
| } |
| |
| return ret; |
| } |
| |
| static coroutine_fn int qcow_co_pwritev(BlockDriverState *bs, uint64_t offset, |
| uint64_t bytes, QEMUIOVector *qiov, |
| int flags) |
| { |
| BDRVQcowState *s = bs->opaque; |
| int offset_in_cluster; |
| uint64_t cluster_offset; |
| int ret = 0, n; |
| uint8_t *buf; |
| void *orig_buf; |
| |
| assert(!flags); |
| s->cluster_cache_offset = -1; /* disable compressed cache */ |
| |
| /* We must always copy the iov when encrypting, so we |
| * don't modify the original data buffer during encryption */ |
| if (bs->encrypted || qiov->niov > 1) { |
| buf = orig_buf = qemu_try_blockalign(bs, qiov->size); |
| if (buf == NULL) { |
| return -ENOMEM; |
| } |
| qemu_iovec_to_buf(qiov, 0, buf, qiov->size); |
| } else { |
| orig_buf = NULL; |
| buf = (uint8_t *)qiov->iov->iov_base; |
| } |
| |
| qemu_co_mutex_lock(&s->lock); |
| |
| while (bytes != 0) { |
| offset_in_cluster = offset & (s->cluster_size - 1); |
| n = s->cluster_size - offset_in_cluster; |
| if (n > bytes) { |
| n = bytes; |
| } |
| ret = get_cluster_offset(bs, offset, 1, 0, offset_in_cluster, |
| offset_in_cluster + n, &cluster_offset); |
| if (ret < 0) { |
| break; |
| } |
| if (!cluster_offset || (cluster_offset & 511) != 0) { |
| ret = -EIO; |
| break; |
| } |
| if (bs->encrypted) { |
| assert(s->crypto); |
| if (qcrypto_block_encrypt(s->crypto, offset, buf, n, NULL) < 0) { |
| ret = -EIO; |
| break; |
| } |
| } |
| |
| qemu_co_mutex_unlock(&s->lock); |
| BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO); |
| ret = bdrv_co_pwrite(bs->file, cluster_offset + offset_in_cluster, |
| n, buf, 0); |
| qemu_co_mutex_lock(&s->lock); |
| if (ret < 0) { |
| break; |
| } |
| ret = 0; |
| |
| bytes -= n; |
| offset += n; |
| buf += n; |
| } |
| qemu_co_mutex_unlock(&s->lock); |
| |
| qemu_vfree(orig_buf); |
| |
| return ret; |
| } |
| |
| static void qcow_close(BlockDriverState *bs) |
| { |
| BDRVQcowState *s = bs->opaque; |
| |
| qcrypto_block_free(s->crypto); |
| s->crypto = NULL; |
| g_free(s->l1_table); |
| qemu_vfree(s->l2_cache); |
| g_free(s->cluster_cache); |
| g_free(s->cluster_data); |
| |
| migrate_del_blocker(s->migration_blocker); |
| error_free(s->migration_blocker); |
| } |
| |
| static int coroutine_fn qcow_co_create(BlockdevCreateOptions *opts, |
| Error **errp) |
| { |
| BlockdevCreateOptionsQcow *qcow_opts; |
| int header_size, backing_filename_len, l1_size, shift, i; |
| QCowHeader header; |
| uint8_t *tmp; |
| int64_t total_size = 0; |
| int ret; |
| BlockDriverState *bs; |
| BlockBackend *qcow_blk; |
| QCryptoBlock *crypto = NULL; |
| |
| assert(opts->driver == BLOCKDEV_DRIVER_QCOW); |
| qcow_opts = &opts->u.qcow; |
| |
| /* Sanity checks */ |
| total_size = qcow_opts->size; |
| if (total_size == 0) { |
| error_setg(errp, "Image size is too small, cannot be zero length"); |
| return -EINVAL; |
| } |
| |
| if (qcow_opts->has_encrypt && |
| qcow_opts->encrypt->format != Q_CRYPTO_BLOCK_FORMAT_QCOW) |
| { |
| error_setg(errp, "Unsupported encryption format"); |
| return -EINVAL; |
| } |
| |
| /* Create BlockBackend to write to the image */ |
| bs = bdrv_open_blockdev_ref(qcow_opts->file, errp); |
| if (bs == NULL) { |
| return -EIO; |
| } |
| |
| qcow_blk = blk_new(bdrv_get_aio_context(bs), |
| BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL); |
| ret = blk_insert_bs(qcow_blk, bs, errp); |
| if (ret < 0) { |
| goto exit; |
| } |
| blk_set_allow_write_beyond_eof(qcow_blk, true); |
| |
| /* Create image format */ |
| ret = blk_truncate(qcow_blk, 0, PREALLOC_MODE_OFF, errp); |
| if (ret < 0) { |
| goto exit; |
| } |
| |
| memset(&header, 0, sizeof(header)); |
| header.magic = cpu_to_be32(QCOW_MAGIC); |
| header.version = cpu_to_be32(QCOW_VERSION); |
| header.size = cpu_to_be64(total_size); |
| header_size = sizeof(header); |
| backing_filename_len = 0; |
| if (qcow_opts->has_backing_file) { |
| if (strcmp(qcow_opts->backing_file, "fat:")) { |
| header.backing_file_offset = cpu_to_be64(header_size); |
| backing_filename_len = strlen(qcow_opts->backing_file); |
| header.backing_file_size = cpu_to_be32(backing_filename_len); |
| header_size += backing_filename_len; |
| } else { |
| /* special backing file for vvfat */ |
| qcow_opts->has_backing_file = false; |
| } |
| header.cluster_bits = 9; /* 512 byte cluster to avoid copying |
| unmodified sectors */ |
| header.l2_bits = 12; /* 32 KB L2 tables */ |
| } else { |
| header.cluster_bits = 12; /* 4 KB clusters */ |
| header.l2_bits = 9; /* 4 KB L2 tables */ |
| } |
| header_size = (header_size + 7) & ~7; |
| shift = header.cluster_bits + header.l2_bits; |
| l1_size = (total_size + (1LL << shift) - 1) >> shift; |
| |
| header.l1_table_offset = cpu_to_be64(header_size); |
| |
| if (qcow_opts->has_encrypt) { |
| header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES); |
| |
| crypto = qcrypto_block_create(qcow_opts->encrypt, "encrypt.", |
| NULL, NULL, NULL, errp); |
| if (!crypto) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| } else { |
| header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); |
| } |
| |
| /* write all the data */ |
| ret = blk_pwrite(qcow_blk, 0, &header, sizeof(header), 0); |
| if (ret != sizeof(header)) { |
| goto exit; |
| } |
| |
| if (qcow_opts->has_backing_file) { |
| ret = blk_pwrite(qcow_blk, sizeof(header), |
| qcow_opts->backing_file, backing_filename_len, 0); |
| if (ret != backing_filename_len) { |
| goto exit; |
| } |
| } |
| |
| tmp = g_malloc0(BDRV_SECTOR_SIZE); |
| for (i = 0; i < DIV_ROUND_UP(sizeof(uint64_t) * l1_size, BDRV_SECTOR_SIZE); |
| i++) { |
| ret = blk_pwrite(qcow_blk, header_size + BDRV_SECTOR_SIZE * i, |
| tmp, BDRV_SECTOR_SIZE, 0); |
| if (ret != BDRV_SECTOR_SIZE) { |
| g_free(tmp); |
| goto exit; |
| } |
| } |
| |
| g_free(tmp); |
| ret = 0; |
| exit: |
| blk_unref(qcow_blk); |
| bdrv_unref(bs); |
| qcrypto_block_free(crypto); |
| return ret; |
| } |
| |
| static int coroutine_fn qcow_co_create_opts(const char *filename, |
| QemuOpts *opts, Error **errp) |
| { |
| BlockdevCreateOptions *create_options = NULL; |
| BlockDriverState *bs = NULL; |
| QDict *qdict; |
| Visitor *v; |
| const char *val; |
| Error *local_err = NULL; |
| int ret; |
| |
| static const QDictRenames opt_renames[] = { |
| { BLOCK_OPT_BACKING_FILE, "backing-file" }, |
| { BLOCK_OPT_ENCRYPT, BLOCK_OPT_ENCRYPT_FORMAT }, |
| { NULL, NULL }, |
| }; |
| |
| /* Parse options and convert legacy syntax */ |
| qdict = qemu_opts_to_qdict_filtered(opts, NULL, &qcow_create_opts, true); |
| |
| 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"); |
| } |
| |
| if (!qdict_rename_keys(qdict, opt_renames, errp)) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* Create and open the file (protocol layer) */ |
| ret = bdrv_create_file(filename, opts, &local_err); |
| if (ret < 0) { |
| error_propagate(errp, local_err); |
| goto fail; |
| } |
| |
| bs = bdrv_open(filename, NULL, NULL, |
| BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, errp); |
| if (bs == NULL) { |
| ret = -EIO; |
| goto fail; |
| } |
| |
| /* Now get the QAPI type BlockdevCreateOptions */ |
| qdict_put_str(qdict, "driver", "qcow"); |
| qdict_put_str(qdict, "file", bs->node_name); |
| |
| v = qobject_input_visitor_new_flat_confused(qdict, errp); |
| if (!v) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| visit_type_BlockdevCreateOptions(v, NULL, &create_options, &local_err); |
| visit_free(v); |
| |
| if (local_err) { |
| error_propagate(errp, local_err); |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* Silently round up size */ |
| assert(create_options->driver == BLOCKDEV_DRIVER_QCOW); |
| create_options->u.qcow.size = |
| ROUND_UP(create_options->u.qcow.size, BDRV_SECTOR_SIZE); |
| |
| /* Create the qcow image (format layer) */ |
| ret = qcow_co_create(create_options, errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = 0; |
| fail: |
| qobject_unref(qdict); |
| bdrv_unref(bs); |
| qapi_free_BlockdevCreateOptions(create_options); |
| return ret; |
| } |
| |
| static int qcow_make_empty(BlockDriverState *bs) |
| { |
| BDRVQcowState *s = bs->opaque; |
| uint32_t l1_length = s->l1_size * sizeof(uint64_t); |
| int ret; |
| |
| memset(s->l1_table, 0, l1_length); |
| if (bdrv_pwrite_sync(bs->file, s->l1_table_offset, s->l1_table, |
| l1_length) < 0) |
| return -1; |
| ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length, |
| PREALLOC_MODE_OFF, NULL); |
| if (ret < 0) |
| return ret; |
| |
| memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); |
| memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t)); |
| memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t)); |
| |
| return 0; |
| } |
| |
| /* XXX: put compressed sectors first, then all the cluster aligned |
| tables to avoid losing bytes in alignment */ |
| static coroutine_fn int |
| qcow_co_pwritev_compressed(BlockDriverState *bs, uint64_t offset, |
| uint64_t bytes, QEMUIOVector *qiov) |
| { |
| BDRVQcowState *s = bs->opaque; |
| z_stream strm; |
| int ret, out_len; |
| uint8_t *buf, *out_buf; |
| uint64_t cluster_offset; |
| |
| buf = qemu_blockalign(bs, s->cluster_size); |
| if (bytes != s->cluster_size) { |
| if (bytes > s->cluster_size || |
| offset + bytes != bs->total_sectors << BDRV_SECTOR_BITS) |
| { |
| qemu_vfree(buf); |
| return -EINVAL; |
| } |
| /* Zero-pad last write if image size is not cluster aligned */ |
| memset(buf + bytes, 0, s->cluster_size - bytes); |
| } |
| qemu_iovec_to_buf(qiov, 0, buf, qiov->size); |
| |
| out_buf = g_malloc(s->cluster_size); |
| |
| /* best compression, small window, no zlib header */ |
| memset(&strm, 0, sizeof(strm)); |
| ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, |
| Z_DEFLATED, -12, |
| 9, Z_DEFAULT_STRATEGY); |
| if (ret != 0) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| strm.avail_in = s->cluster_size; |
| strm.next_in = (uint8_t *)buf; |
| strm.avail_out = s->cluster_size; |
| strm.next_out = out_buf; |
| |
| ret = deflate(&strm, Z_FINISH); |
| if (ret != Z_STREAM_END && ret != Z_OK) { |
| deflateEnd(&strm); |
| ret = -EINVAL; |
| goto fail; |
| } |
| out_len = strm.next_out - out_buf; |
| |
| deflateEnd(&strm); |
| |
| if (ret != Z_STREAM_END || out_len >= s->cluster_size) { |
| /* could not compress: write normal cluster */ |
| ret = qcow_co_pwritev(bs, offset, bytes, qiov, 0); |
| if (ret < 0) { |
| goto fail; |
| } |
| goto success; |
| } |
| qemu_co_mutex_lock(&s->lock); |
| ret = get_cluster_offset(bs, offset, 2, out_len, 0, 0, &cluster_offset); |
| qemu_co_mutex_unlock(&s->lock); |
| if (ret < 0) { |
| goto fail; |
| } |
| if (cluster_offset == 0) { |
| ret = -EIO; |
| goto fail; |
| } |
| cluster_offset &= s->cluster_offset_mask; |
| |
| BLKDBG_EVENT(bs->file, BLKDBG_WRITE_COMPRESSED); |
| ret = bdrv_co_pwrite(bs->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 int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
| { |
| BDRVQcowState *s = bs->opaque; |
| bdi->cluster_size = s->cluster_size; |
| return 0; |
| } |
| |
| static QemuOptsList qcow_create_opts = { |
| .name = "qcow-create-opts", |
| .head = QTAILQ_HEAD_INITIALIZER(qcow_create_opts.head), |
| .desc = { |
| { |
| .name = BLOCK_OPT_SIZE, |
| .type = QEMU_OPT_SIZE, |
| .help = "Virtual disk size" |
| }, |
| { |
| .name = BLOCK_OPT_BACKING_FILE, |
| .type = QEMU_OPT_STRING, |
| .help = "File name of a base image" |
| }, |
| { |
| .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'", |
| }, |
| BLOCK_CRYPTO_OPT_DEF_QCOW_KEY_SECRET("encrypt."), |
| { /* end of list */ } |
| } |
| }; |
| |
| static const char *const qcow_strong_runtime_opts[] = { |
| "encrypt." BLOCK_CRYPTO_OPT_QCOW_KEY_SECRET, |
| |
| NULL |
| }; |
| |
| static BlockDriver bdrv_qcow = { |
| .format_name = "qcow", |
| .instance_size = sizeof(BDRVQcowState), |
| .bdrv_probe = qcow_probe, |
| .bdrv_open = qcow_open, |
| .bdrv_close = qcow_close, |
| .bdrv_child_perm = bdrv_format_default_perms, |
| .bdrv_reopen_prepare = qcow_reopen_prepare, |
| .bdrv_co_create = qcow_co_create, |
| .bdrv_co_create_opts = qcow_co_create_opts, |
| .bdrv_has_zero_init = bdrv_has_zero_init_1, |
| .supports_backing = true, |
| .bdrv_refresh_limits = qcow_refresh_limits, |
| |
| .bdrv_co_preadv = qcow_co_preadv, |
| .bdrv_co_pwritev = qcow_co_pwritev, |
| .bdrv_co_block_status = qcow_co_block_status, |
| |
| .bdrv_make_empty = qcow_make_empty, |
| .bdrv_co_pwritev_compressed = qcow_co_pwritev_compressed, |
| .bdrv_get_info = qcow_get_info, |
| |
| .create_opts = &qcow_create_opts, |
| .strong_runtime_opts = qcow_strong_runtime_opts, |
| }; |
| |
| static void bdrv_qcow_init(void) |
| { |
| bdrv_register(&bdrv_qcow); |
| } |
| |
| block_init(bdrv_qcow_init); |