| /* |
| * Block driver for the Virtual Disk Image (VDI) format |
| * |
| * Copyright (c) 2009 Stefan Weil |
| * |
| * This program is free software: you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation, either version 2 of the License, or |
| * (at your option) version 3 or any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| * |
| * Reference: |
| * http://forums.virtualbox.org/viewtopic.php?t=8046 |
| * |
| * This driver supports create / read / write operations on VDI images. |
| * |
| * Todo (see also TODO in code): |
| * |
| * Some features like snapshots are still missing. |
| * |
| * Deallocation of zero-filled blocks and shrinking images are missing, too |
| * (might be added to common block layer). |
| * |
| * Allocation of blocks could be optimized (less writes to block map and |
| * header). |
| * |
| * Read and write of adjacents blocks could be done in one operation |
| * (current code uses one operation per block (1 MiB). |
| * |
| * The code is not thread safe (missing locks for changes in header and |
| * block table, no problem with current QEMU). |
| * |
| * Hints: |
| * |
| * Blocks (VDI documentation) correspond to clusters (QEMU). |
| * QEMU's backing files could be implemented using VDI snapshot files (TODO). |
| * VDI snapshot files may also contain the complete machine state. |
| * Maybe this machine state can be converted to QEMU PC machine snapshot data. |
| * |
| * The driver keeps a block cache (little endian entries) in memory. |
| * For the standard block size (1 MiB), a 1 TiB disk will use 4 MiB RAM, |
| * so this seems to be reasonable. |
| */ |
| |
| #include "qemu-common.h" |
| #include "block_int.h" |
| #include "module.h" |
| |
| #if defined(CONFIG_UUID) |
| #include <uuid/uuid.h> |
| #else |
| /* TODO: move uuid emulation to some central place in QEMU. */ |
| #include "sysemu.h" /* UUID_FMT */ |
| typedef unsigned char uuid_t[16]; |
| void uuid_generate(uuid_t out); |
| int uuid_is_null(const uuid_t uu); |
| void uuid_unparse(const uuid_t uu, char *out); |
| #endif |
| |
| /* Code configuration options. */ |
| |
| /* Enable debug messages. */ |
| //~ #define CONFIG_VDI_DEBUG |
| |
| /* Support write operations on VDI images. */ |
| #define CONFIG_VDI_WRITE |
| |
| /* Support non-standard block (cluster) size. This is untested. |
| * Maybe it will be needed for very large images. |
| */ |
| //~ #define CONFIG_VDI_BLOCK_SIZE |
| |
| /* Support static (fixed, pre-allocated) images. */ |
| #define CONFIG_VDI_STATIC_IMAGE |
| |
| /* Command line option for static images. */ |
| #define BLOCK_OPT_STATIC "static" |
| |
| #define KiB 1024 |
| #define MiB (KiB * KiB) |
| |
| #define SECTOR_SIZE 512 |
| |
| #if defined(CONFIG_VDI_DEBUG) |
| #define logout(fmt, ...) \ |
| fprintf(stderr, "vdi\t%-24s" fmt, __func__, ##__VA_ARGS__) |
| #else |
| #define logout(fmt, ...) ((void)0) |
| #endif |
| |
| /* Image signature. */ |
| #define VDI_SIGNATURE 0xbeda107f |
| |
| /* Image version. */ |
| #define VDI_VERSION_1_1 0x00010001 |
| |
| /* Image type. */ |
| #define VDI_TYPE_DYNAMIC 1 |
| #define VDI_TYPE_STATIC 2 |
| |
| /* Innotek / SUN images use these strings in header.text: |
| * "<<< innotek VirtualBox Disk Image >>>\n" |
| * "<<< Sun xVM VirtualBox Disk Image >>>\n" |
| * "<<< Sun VirtualBox Disk Image >>>\n" |
| * The value does not matter, so QEMU created images use a different text. |
| */ |
| #define VDI_TEXT "<<< QEMU VM Virtual Disk Image >>>\n" |
| |
| /* Unallocated blocks use this index (no need to convert endianess). */ |
| #define VDI_UNALLOCATED UINT32_MAX |
| |
| #if !defined(CONFIG_UUID) |
| void uuid_generate(uuid_t out) |
| { |
| memset(out, 0, sizeof(out)); |
| } |
| |
| int uuid_is_null(const uuid_t uu) |
| { |
| uuid_t null_uuid = { 0 }; |
| return memcmp(uu, null_uuid, sizeof(uu)) == 0; |
| } |
| |
| void uuid_unparse(const uuid_t uu, char *out) |
| { |
| snprintf(out, 37, UUID_FMT, |
| uu[0], uu[1], uu[2], uu[3], uu[4], uu[5], uu[6], uu[7], |
| uu[8], uu[9], uu[10], uu[11], uu[12], uu[13], uu[14], uu[15]); |
| } |
| #endif |
| |
| typedef struct { |
| BlockDriverAIOCB common; |
| int64_t sector_num; |
| QEMUIOVector *qiov; |
| uint8_t *buf; |
| /* Total number of sectors. */ |
| int nb_sectors; |
| /* Number of sectors for current AIO. */ |
| int n_sectors; |
| /* New allocated block map entry. */ |
| uint32_t bmap_first; |
| uint32_t bmap_last; |
| /* Buffer for new allocated block. */ |
| void *block_buffer; |
| void *orig_buf; |
| int header_modified; |
| BlockDriverAIOCB *hd_aiocb; |
| struct iovec hd_iov; |
| QEMUIOVector hd_qiov; |
| QEMUBH *bh; |
| } VdiAIOCB; |
| |
| typedef struct { |
| char text[0x40]; |
| uint32_t signature; |
| uint32_t version; |
| uint32_t header_size; |
| uint32_t image_type; |
| uint32_t image_flags; |
| char description[256]; |
| uint32_t offset_bmap; |
| uint32_t offset_data; |
| uint32_t cylinders; /* disk geometry, unused here */ |
| uint32_t heads; /* disk geometry, unused here */ |
| uint32_t sectors; /* disk geometry, unused here */ |
| uint32_t sector_size; |
| uint32_t unused1; |
| uint64_t disk_size; |
| uint32_t block_size; |
| uint32_t block_extra; /* unused here */ |
| uint32_t blocks_in_image; |
| uint32_t blocks_allocated; |
| uuid_t uuid_image; |
| uuid_t uuid_last_snap; |
| uuid_t uuid_link; |
| uuid_t uuid_parent; |
| uint64_t unused2[7]; |
| } VdiHeader; |
| |
| typedef struct { |
| BlockDriverState *hd; |
| /* The block map entries are little endian (even in memory). */ |
| uint32_t *bmap; |
| /* Size of block (bytes). */ |
| uint32_t block_size; |
| /* Size of block (sectors). */ |
| uint32_t block_sectors; |
| /* First sector of block map. */ |
| uint32_t bmap_sector; |
| /* VDI header (converted to host endianess). */ |
| VdiHeader header; |
| } BDRVVdiState; |
| |
| /* Change UUID from little endian (IPRT = VirtualBox format) to big endian |
| * format (network byte order, standard, see RFC 4122) and vice versa. |
| */ |
| static void uuid_convert(uuid_t uuid) |
| { |
| bswap32s((uint32_t *)&uuid[0]); |
| bswap16s((uint16_t *)&uuid[4]); |
| bswap16s((uint16_t *)&uuid[6]); |
| } |
| |
| static void vdi_header_to_cpu(VdiHeader *header) |
| { |
| le32_to_cpus(&header->signature); |
| le32_to_cpus(&header->version); |
| le32_to_cpus(&header->header_size); |
| le32_to_cpus(&header->image_type); |
| le32_to_cpus(&header->image_flags); |
| le32_to_cpus(&header->offset_bmap); |
| le32_to_cpus(&header->offset_data); |
| le32_to_cpus(&header->cylinders); |
| le32_to_cpus(&header->heads); |
| le32_to_cpus(&header->sectors); |
| le32_to_cpus(&header->sector_size); |
| le64_to_cpus(&header->disk_size); |
| le32_to_cpus(&header->block_size); |
| le32_to_cpus(&header->block_extra); |
| le32_to_cpus(&header->blocks_in_image); |
| le32_to_cpus(&header->blocks_allocated); |
| uuid_convert(header->uuid_image); |
| uuid_convert(header->uuid_last_snap); |
| uuid_convert(header->uuid_link); |
| uuid_convert(header->uuid_parent); |
| } |
| |
| static void vdi_header_to_le(VdiHeader *header) |
| { |
| cpu_to_le32s(&header->signature); |
| cpu_to_le32s(&header->version); |
| cpu_to_le32s(&header->header_size); |
| cpu_to_le32s(&header->image_type); |
| cpu_to_le32s(&header->image_flags); |
| cpu_to_le32s(&header->offset_bmap); |
| cpu_to_le32s(&header->offset_data); |
| cpu_to_le32s(&header->cylinders); |
| cpu_to_le32s(&header->heads); |
| cpu_to_le32s(&header->sectors); |
| cpu_to_le32s(&header->sector_size); |
| cpu_to_le64s(&header->disk_size); |
| cpu_to_le32s(&header->block_size); |
| cpu_to_le32s(&header->block_extra); |
| cpu_to_le32s(&header->blocks_in_image); |
| cpu_to_le32s(&header->blocks_allocated); |
| cpu_to_le32s(&header->blocks_allocated); |
| uuid_convert(header->uuid_image); |
| uuid_convert(header->uuid_last_snap); |
| uuid_convert(header->uuid_link); |
| uuid_convert(header->uuid_parent); |
| } |
| |
| #if defined(CONFIG_VDI_DEBUG) |
| static void vdi_header_print(VdiHeader *header) |
| { |
| char uuid[37]; |
| logout("text %s", header->text); |
| logout("signature 0x%04x\n", header->signature); |
| logout("header size 0x%04x\n", header->header_size); |
| logout("image type 0x%04x\n", header->image_type); |
| logout("image flags 0x%04x\n", header->image_flags); |
| logout("description %s\n", header->description); |
| logout("offset bmap 0x%04x\n", header->offset_bmap); |
| logout("offset data 0x%04x\n", header->offset_data); |
| logout("cylinders 0x%04x\n", header->cylinders); |
| logout("heads 0x%04x\n", header->heads); |
| logout("sectors 0x%04x\n", header->sectors); |
| logout("sector size 0x%04x\n", header->sector_size); |
| logout("image size 0x%" PRIx64 " B (%" PRIu64 " MiB)\n", |
| header->disk_size, header->disk_size / MiB); |
| logout("block size 0x%04x\n", header->block_size); |
| logout("block extra 0x%04x\n", header->block_extra); |
| logout("blocks tot. 0x%04x\n", header->blocks_in_image); |
| logout("blocks all. 0x%04x\n", header->blocks_allocated); |
| uuid_unparse(header->uuid_image, uuid); |
| logout("uuid image %s\n", uuid); |
| uuid_unparse(header->uuid_last_snap, uuid); |
| logout("uuid snap %s\n", uuid); |
| uuid_unparse(header->uuid_link, uuid); |
| logout("uuid link %s\n", uuid); |
| uuid_unparse(header->uuid_parent, uuid); |
| logout("uuid parent %s\n", uuid); |
| } |
| #endif |
| |
| static int vdi_check(BlockDriverState *bs, BdrvCheckResult *res) |
| { |
| /* TODO: additional checks possible. */ |
| BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
| uint32_t blocks_allocated = 0; |
| uint32_t block; |
| uint32_t *bmap; |
| logout("\n"); |
| |
| bmap = qemu_malloc(s->header.blocks_in_image * sizeof(uint32_t)); |
| memset(bmap, 0xff, s->header.blocks_in_image * sizeof(uint32_t)); |
| |
| /* Check block map and value of blocks_allocated. */ |
| for (block = 0; block < s->header.blocks_in_image; block++) { |
| uint32_t bmap_entry = le32_to_cpu(s->bmap[block]); |
| if (bmap_entry != VDI_UNALLOCATED) { |
| if (bmap_entry < s->header.blocks_in_image) { |
| blocks_allocated++; |
| if (bmap[bmap_entry] == VDI_UNALLOCATED) { |
| bmap[bmap_entry] = bmap_entry; |
| } else { |
| fprintf(stderr, "ERROR: block index %" PRIu32 |
| " also used by %" PRIu32 "\n", bmap[bmap_entry], bmap_entry); |
| res->corruptions++; |
| } |
| } else { |
| fprintf(stderr, "ERROR: block index %" PRIu32 |
| " too large, is %" PRIu32 "\n", block, bmap_entry); |
| res->corruptions++; |
| } |
| } |
| } |
| if (blocks_allocated != s->header.blocks_allocated) { |
| fprintf(stderr, "ERROR: allocated blocks mismatch, is %" PRIu32 |
| ", should be %" PRIu32 "\n", |
| blocks_allocated, s->header.blocks_allocated); |
| res->corruptions++; |
| } |
| |
| qemu_free(bmap); |
| |
| return 0; |
| } |
| |
| static int vdi_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
| { |
| /* TODO: vdi_get_info would be needed for machine snapshots. |
| vm_state_offset is still missing. */ |
| BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
| logout("\n"); |
| bdi->cluster_size = s->block_size; |
| bdi->vm_state_offset = 0; |
| return 0; |
| } |
| |
| static int vdi_make_empty(BlockDriverState *bs) |
| { |
| /* TODO: missing code. */ |
| logout("\n"); |
| /* The return value for missing code must be 0, see block.c. */ |
| return 0; |
| } |
| |
| static int vdi_probe(const uint8_t *buf, int buf_size, const char *filename) |
| { |
| const VdiHeader *header = (const VdiHeader *)buf; |
| int result = 0; |
| |
| logout("\n"); |
| |
| if (buf_size < sizeof(*header)) { |
| /* Header too small, no VDI. */ |
| } else if (le32_to_cpu(header->signature) == VDI_SIGNATURE) { |
| result = 100; |
| } |
| |
| if (result == 0) { |
| logout("no vdi image\n"); |
| } else { |
| logout("%s", header->text); |
| } |
| |
| return result; |
| } |
| |
| static int vdi_open(BlockDriverState *bs, int flags) |
| { |
| BDRVVdiState *s = bs->opaque; |
| VdiHeader header; |
| size_t bmap_size; |
| |
| logout("\n"); |
| |
| if (bdrv_read(bs->file, 0, (uint8_t *)&header, 1) < 0) { |
| goto fail; |
| } |
| |
| vdi_header_to_cpu(&header); |
| #if defined(CONFIG_VDI_DEBUG) |
| vdi_header_print(&header); |
| #endif |
| |
| if (header.disk_size % SECTOR_SIZE != 0) { |
| /* 'VBoxManage convertfromraw' can create images with odd disk sizes. |
| We accept them but round the disk size to the next multiple of |
| SECTOR_SIZE. */ |
| logout("odd disk size %" PRIu64 " B, round up\n", header.disk_size); |
| header.disk_size += SECTOR_SIZE - 1; |
| header.disk_size &= ~(SECTOR_SIZE - 1); |
| } |
| |
| if (header.version != VDI_VERSION_1_1) { |
| logout("unsupported version %u.%u\n", |
| header.version >> 16, header.version & 0xffff); |
| goto fail; |
| } else if (header.offset_bmap % SECTOR_SIZE != 0) { |
| /* We only support block maps which start on a sector boundary. */ |
| logout("unsupported block map offset 0x%x B\n", header.offset_bmap); |
| goto fail; |
| } else if (header.offset_data % SECTOR_SIZE != 0) { |
| /* We only support data blocks which start on a sector boundary. */ |
| logout("unsupported data offset 0x%x B\n", header.offset_data); |
| goto fail; |
| } else if (header.sector_size != SECTOR_SIZE) { |
| logout("unsupported sector size %u B\n", header.sector_size); |
| goto fail; |
| } else if (header.block_size != 1 * MiB) { |
| logout("unsupported block size %u B\n", header.block_size); |
| goto fail; |
| } else if (header.disk_size > |
| (uint64_t)header.blocks_in_image * header.block_size) { |
| logout("unsupported disk size %" PRIu64 " B\n", header.disk_size); |
| goto fail; |
| } else if (!uuid_is_null(header.uuid_link)) { |
| logout("link uuid != 0, unsupported\n"); |
| goto fail; |
| } else if (!uuid_is_null(header.uuid_parent)) { |
| logout("parent uuid != 0, unsupported\n"); |
| goto fail; |
| } |
| |
| bs->total_sectors = header.disk_size / SECTOR_SIZE; |
| |
| s->block_size = header.block_size; |
| s->block_sectors = header.block_size / SECTOR_SIZE; |
| s->bmap_sector = header.offset_bmap / SECTOR_SIZE; |
| s->header = header; |
| |
| bmap_size = header.blocks_in_image * sizeof(uint32_t); |
| bmap_size = (bmap_size + SECTOR_SIZE - 1) / SECTOR_SIZE; |
| if (bmap_size > 0) { |
| s->bmap = qemu_malloc(bmap_size * SECTOR_SIZE); |
| } |
| if (bdrv_read(bs->file, s->bmap_sector, (uint8_t *)s->bmap, bmap_size) < 0) { |
| goto fail_free_bmap; |
| } |
| |
| return 0; |
| |
| fail_free_bmap: |
| qemu_free(s->bmap); |
| |
| fail: |
| return -1; |
| } |
| |
| static int vdi_is_allocated(BlockDriverState *bs, int64_t sector_num, |
| int nb_sectors, int *pnum) |
| { |
| /* TODO: Check for too large sector_num (in bdrv_is_allocated or here). */ |
| BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
| size_t bmap_index = sector_num / s->block_sectors; |
| size_t sector_in_block = sector_num % s->block_sectors; |
| int n_sectors = s->block_sectors - sector_in_block; |
| uint32_t bmap_entry = le32_to_cpu(s->bmap[bmap_index]); |
| logout("%p, %" PRId64 ", %d, %p\n", bs, sector_num, nb_sectors, pnum); |
| if (n_sectors > nb_sectors) { |
| n_sectors = nb_sectors; |
| } |
| *pnum = n_sectors; |
| return bmap_entry != VDI_UNALLOCATED; |
| } |
| |
| static void vdi_aio_cancel(BlockDriverAIOCB *blockacb) |
| { |
| /* TODO: This code is untested. How can I get it executed? */ |
| VdiAIOCB *acb = container_of(blockacb, VdiAIOCB, common); |
| logout("\n"); |
| if (acb->hd_aiocb) { |
| bdrv_aio_cancel(acb->hd_aiocb); |
| } |
| qemu_aio_release(acb); |
| } |
| |
| static AIOPool vdi_aio_pool = { |
| .aiocb_size = sizeof(VdiAIOCB), |
| .cancel = vdi_aio_cancel, |
| }; |
| |
| static VdiAIOCB *vdi_aio_setup(BlockDriverState *bs, int64_t sector_num, |
| QEMUIOVector *qiov, int nb_sectors, |
| BlockDriverCompletionFunc *cb, void *opaque, int is_write) |
| { |
| VdiAIOCB *acb; |
| |
| logout("%p, %" PRId64 ", %p, %d, %p, %p, %d\n", |
| bs, sector_num, qiov, nb_sectors, cb, opaque, is_write); |
| |
| acb = qemu_aio_get(&vdi_aio_pool, bs, cb, opaque); |
| if (acb) { |
| acb->hd_aiocb = NULL; |
| acb->sector_num = sector_num; |
| acb->qiov = qiov; |
| if (qiov->niov > 1) { |
| acb->buf = qemu_blockalign(bs, qiov->size); |
| acb->orig_buf = acb->buf; |
| if (is_write) { |
| qemu_iovec_to_buffer(qiov, acb->buf); |
| } |
| } else { |
| acb->buf = (uint8_t *)qiov->iov->iov_base; |
| } |
| acb->nb_sectors = nb_sectors; |
| acb->n_sectors = 0; |
| acb->bmap_first = VDI_UNALLOCATED; |
| acb->bmap_last = VDI_UNALLOCATED; |
| acb->block_buffer = NULL; |
| acb->header_modified = 0; |
| } |
| return acb; |
| } |
| |
| static int vdi_schedule_bh(QEMUBHFunc *cb, VdiAIOCB *acb) |
| { |
| logout("\n"); |
| |
| if (acb->bh) { |
| return -EIO; |
| } |
| |
| acb->bh = qemu_bh_new(cb, acb); |
| if (!acb->bh) { |
| return -EIO; |
| } |
| |
| qemu_bh_schedule(acb->bh); |
| |
| return 0; |
| } |
| |
| static void vdi_aio_read_cb(void *opaque, int ret); |
| |
| static void vdi_aio_read_bh(void *opaque) |
| { |
| VdiAIOCB *acb = opaque; |
| logout("\n"); |
| qemu_bh_delete(acb->bh); |
| acb->bh = NULL; |
| vdi_aio_read_cb(opaque, 0); |
| } |
| |
| static void vdi_aio_read_cb(void *opaque, int ret) |
| { |
| VdiAIOCB *acb = opaque; |
| BlockDriverState *bs = acb->common.bs; |
| BDRVVdiState *s = bs->opaque; |
| uint32_t bmap_entry; |
| uint32_t block_index; |
| uint32_t sector_in_block; |
| uint32_t n_sectors; |
| |
| logout("%u sectors read\n", acb->n_sectors); |
| |
| acb->hd_aiocb = NULL; |
| |
| if (ret < 0) { |
| goto done; |
| } |
| |
| acb->nb_sectors -= acb->n_sectors; |
| |
| if (acb->nb_sectors == 0) { |
| /* request completed */ |
| ret = 0; |
| goto done; |
| } |
| |
| acb->sector_num += acb->n_sectors; |
| acb->buf += acb->n_sectors * SECTOR_SIZE; |
| |
| block_index = acb->sector_num / s->block_sectors; |
| sector_in_block = acb->sector_num % s->block_sectors; |
| n_sectors = s->block_sectors - sector_in_block; |
| if (n_sectors > acb->nb_sectors) { |
| n_sectors = acb->nb_sectors; |
| } |
| |
| logout("will read %u sectors starting at sector %" PRIu64 "\n", |
| n_sectors, acb->sector_num); |
| |
| /* prepare next AIO request */ |
| acb->n_sectors = n_sectors; |
| bmap_entry = le32_to_cpu(s->bmap[block_index]); |
| if (bmap_entry == VDI_UNALLOCATED) { |
| /* Block not allocated, return zeros, no need to wait. */ |
| memset(acb->buf, 0, n_sectors * SECTOR_SIZE); |
| ret = vdi_schedule_bh(vdi_aio_read_bh, acb); |
| if (ret < 0) { |
| goto done; |
| } |
| } else { |
| uint64_t offset = s->header.offset_data / SECTOR_SIZE + |
| (uint64_t)bmap_entry * s->block_sectors + |
| sector_in_block; |
| acb->hd_iov.iov_base = (void *)acb->buf; |
| acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE; |
| qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1); |
| acb->hd_aiocb = bdrv_aio_readv(bs->file, offset, &acb->hd_qiov, |
| n_sectors, vdi_aio_read_cb, acb); |
| if (acb->hd_aiocb == NULL) { |
| goto done; |
| } |
| } |
| return; |
| done: |
| if (acb->qiov->niov > 1) { |
| qemu_iovec_from_buffer(acb->qiov, acb->orig_buf, acb->qiov->size); |
| qemu_vfree(acb->orig_buf); |
| } |
| acb->common.cb(acb->common.opaque, ret); |
| qemu_aio_release(acb); |
| } |
| |
| static BlockDriverAIOCB *vdi_aio_readv(BlockDriverState *bs, |
| int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, |
| BlockDriverCompletionFunc *cb, void *opaque) |
| { |
| VdiAIOCB *acb; |
| logout("\n"); |
| acb = vdi_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); |
| if (!acb) { |
| return NULL; |
| } |
| vdi_aio_read_cb(acb, 0); |
| return &acb->common; |
| } |
| |
| static void vdi_aio_write_cb(void *opaque, int ret) |
| { |
| VdiAIOCB *acb = opaque; |
| BlockDriverState *bs = acb->common.bs; |
| BDRVVdiState *s = bs->opaque; |
| uint32_t bmap_entry; |
| uint32_t block_index; |
| uint32_t sector_in_block; |
| uint32_t n_sectors; |
| |
| acb->hd_aiocb = NULL; |
| |
| if (ret < 0) { |
| goto done; |
| } |
| |
| acb->nb_sectors -= acb->n_sectors; |
| acb->sector_num += acb->n_sectors; |
| acb->buf += acb->n_sectors * SECTOR_SIZE; |
| |
| if (acb->nb_sectors == 0) { |
| logout("finished data write\n"); |
| acb->n_sectors = 0; |
| if (acb->header_modified) { |
| VdiHeader *header = acb->block_buffer; |
| logout("now writing modified header\n"); |
| assert(acb->bmap_first != VDI_UNALLOCATED); |
| *header = s->header; |
| vdi_header_to_le(header); |
| acb->header_modified = 0; |
| acb->hd_iov.iov_base = acb->block_buffer; |
| acb->hd_iov.iov_len = SECTOR_SIZE; |
| qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1); |
| acb->hd_aiocb = bdrv_aio_writev(bs->file, 0, &acb->hd_qiov, 1, |
| vdi_aio_write_cb, acb); |
| if (acb->hd_aiocb == NULL) { |
| goto done; |
| } |
| return; |
| } else if (acb->bmap_first != VDI_UNALLOCATED) { |
| /* One or more new blocks were allocated. */ |
| uint64_t offset; |
| uint32_t bmap_first; |
| uint32_t bmap_last; |
| qemu_free(acb->block_buffer); |
| acb->block_buffer = NULL; |
| bmap_first = acb->bmap_first; |
| bmap_last = acb->bmap_last; |
| logout("now writing modified block map entry %u...%u\n", |
| bmap_first, bmap_last); |
| /* Write modified sectors from block map. */ |
| bmap_first /= (SECTOR_SIZE / sizeof(uint32_t)); |
| bmap_last /= (SECTOR_SIZE / sizeof(uint32_t)); |
| n_sectors = bmap_last - bmap_first + 1; |
| offset = s->bmap_sector + bmap_first; |
| acb->bmap_first = VDI_UNALLOCATED; |
| acb->hd_iov.iov_base = (void *)((uint8_t *)&s->bmap[0] + |
| bmap_first * SECTOR_SIZE); |
| acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE; |
| qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1); |
| logout("will write %u block map sectors starting from entry %u\n", |
| n_sectors, bmap_first); |
| acb->hd_aiocb = bdrv_aio_writev(bs->file, offset, &acb->hd_qiov, |
| n_sectors, vdi_aio_write_cb, acb); |
| if (acb->hd_aiocb == NULL) { |
| goto done; |
| } |
| return; |
| } |
| ret = 0; |
| goto done; |
| } |
| |
| logout("%u sectors written\n", acb->n_sectors); |
| |
| block_index = acb->sector_num / s->block_sectors; |
| sector_in_block = acb->sector_num % s->block_sectors; |
| n_sectors = s->block_sectors - sector_in_block; |
| if (n_sectors > acb->nb_sectors) { |
| n_sectors = acb->nb_sectors; |
| } |
| |
| logout("will write %u sectors starting at sector %" PRIu64 "\n", |
| n_sectors, acb->sector_num); |
| |
| /* prepare next AIO request */ |
| acb->n_sectors = n_sectors; |
| bmap_entry = le32_to_cpu(s->bmap[block_index]); |
| if (bmap_entry == VDI_UNALLOCATED) { |
| /* Allocate new block and write to it. */ |
| uint64_t offset; |
| uint8_t *block; |
| bmap_entry = s->header.blocks_allocated; |
| s->bmap[block_index] = cpu_to_le32(bmap_entry); |
| s->header.blocks_allocated++; |
| offset = s->header.offset_data / SECTOR_SIZE + |
| (uint64_t)bmap_entry * s->block_sectors; |
| block = acb->block_buffer; |
| if (block == NULL) { |
| block = qemu_mallocz(s->block_size); |
| acb->block_buffer = block; |
| acb->bmap_first = block_index; |
| assert(!acb->header_modified); |
| acb->header_modified = 1; |
| } |
| acb->bmap_last = block_index; |
| memcpy(block + sector_in_block * SECTOR_SIZE, |
| acb->buf, n_sectors * SECTOR_SIZE); |
| acb->hd_iov.iov_base = (void *)block; |
| acb->hd_iov.iov_len = s->block_size; |
| qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1); |
| acb->hd_aiocb = bdrv_aio_writev(bs->file, offset, |
| &acb->hd_qiov, s->block_sectors, |
| vdi_aio_write_cb, acb); |
| if (acb->hd_aiocb == NULL) { |
| goto done; |
| } |
| } else { |
| uint64_t offset = s->header.offset_data / SECTOR_SIZE + |
| (uint64_t)bmap_entry * s->block_sectors + |
| sector_in_block; |
| acb->hd_iov.iov_base = (void *)acb->buf; |
| acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE; |
| qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1); |
| acb->hd_aiocb = bdrv_aio_writev(bs->file, offset, &acb->hd_qiov, |
| n_sectors, vdi_aio_write_cb, acb); |
| if (acb->hd_aiocb == NULL) { |
| goto done; |
| } |
| } |
| |
| return; |
| |
| done: |
| if (acb->qiov->niov > 1) { |
| qemu_vfree(acb->orig_buf); |
| } |
| acb->common.cb(acb->common.opaque, ret); |
| qemu_aio_release(acb); |
| } |
| |
| static BlockDriverAIOCB *vdi_aio_writev(BlockDriverState *bs, |
| int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, |
| BlockDriverCompletionFunc *cb, void *opaque) |
| { |
| VdiAIOCB *acb; |
| logout("\n"); |
| acb = vdi_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 1); |
| if (!acb) { |
| return NULL; |
| } |
| vdi_aio_write_cb(acb, 0); |
| return &acb->common; |
| } |
| |
| static int vdi_create(const char *filename, QEMUOptionParameter *options) |
| { |
| int fd; |
| int result = 0; |
| uint64_t bytes = 0; |
| uint32_t blocks; |
| size_t block_size = 1 * MiB; |
| uint32_t image_type = VDI_TYPE_DYNAMIC; |
| VdiHeader header; |
| size_t i; |
| size_t bmap_size; |
| uint32_t *bmap; |
| |
| logout("\n"); |
| |
| /* Read out options. */ |
| while (options && options->name) { |
| if (!strcmp(options->name, BLOCK_OPT_SIZE)) { |
| bytes = options->value.n; |
| #if defined(CONFIG_VDI_BLOCK_SIZE) |
| } else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) { |
| if (options->value.n) { |
| /* TODO: Additional checks (SECTOR_SIZE * 2^n, ...). */ |
| block_size = options->value.n; |
| } |
| #endif |
| #if defined(CONFIG_VDI_STATIC_IMAGE) |
| } else if (!strcmp(options->name, BLOCK_OPT_STATIC)) { |
| if (options->value.n) { |
| image_type = VDI_TYPE_STATIC; |
| } |
| #endif |
| } |
| options++; |
| } |
| |
| fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, |
| 0644); |
| if (fd < 0) { |
| return -errno; |
| } |
| |
| /* We need enough blocks to store the given disk size, |
| so always round up. */ |
| blocks = (bytes + block_size - 1) / block_size; |
| |
| bmap_size = blocks * sizeof(uint32_t); |
| bmap_size = ((bmap_size + SECTOR_SIZE - 1) & ~(SECTOR_SIZE -1)); |
| |
| memset(&header, 0, sizeof(header)); |
| pstrcpy(header.text, sizeof(header.text), VDI_TEXT); |
| header.signature = VDI_SIGNATURE; |
| header.version = VDI_VERSION_1_1; |
| header.header_size = 0x180; |
| header.image_type = image_type; |
| header.offset_bmap = 0x200; |
| header.offset_data = 0x200 + bmap_size; |
| header.sector_size = SECTOR_SIZE; |
| header.disk_size = bytes; |
| header.block_size = block_size; |
| header.blocks_in_image = blocks; |
| if (image_type == VDI_TYPE_STATIC) { |
| header.blocks_allocated = blocks; |
| } |
| uuid_generate(header.uuid_image); |
| uuid_generate(header.uuid_last_snap); |
| /* There is no need to set header.uuid_link or header.uuid_parent here. */ |
| #if defined(CONFIG_VDI_DEBUG) |
| vdi_header_print(&header); |
| #endif |
| vdi_header_to_le(&header); |
| if (write(fd, &header, sizeof(header)) < 0) { |
| result = -errno; |
| } |
| |
| bmap = NULL; |
| if (bmap_size > 0) { |
| bmap = (uint32_t *)qemu_mallocz(bmap_size); |
| } |
| for (i = 0; i < blocks; i++) { |
| if (image_type == VDI_TYPE_STATIC) { |
| bmap[i] = i; |
| } else { |
| bmap[i] = VDI_UNALLOCATED; |
| } |
| } |
| if (write(fd, bmap, bmap_size) < 0) { |
| result = -errno; |
| } |
| qemu_free(bmap); |
| if (image_type == VDI_TYPE_STATIC) { |
| if (ftruncate(fd, sizeof(header) + bmap_size + blocks * block_size)) { |
| result = -errno; |
| } |
| } |
| |
| if (close(fd) < 0) { |
| result = -errno; |
| } |
| |
| return result; |
| } |
| |
| static void vdi_close(BlockDriverState *bs) |
| { |
| } |
| |
| static int vdi_flush(BlockDriverState *bs) |
| { |
| logout("\n"); |
| return bdrv_flush(bs->file); |
| } |
| |
| |
| static QEMUOptionParameter vdi_create_options[] = { |
| { |
| .name = BLOCK_OPT_SIZE, |
| .type = OPT_SIZE, |
| .help = "Virtual disk size" |
| }, |
| #if defined(CONFIG_VDI_BLOCK_SIZE) |
| { |
| .name = BLOCK_OPT_CLUSTER_SIZE, |
| .type = OPT_SIZE, |
| .help = "VDI cluster (block) size" |
| }, |
| #endif |
| #if defined(CONFIG_VDI_STATIC_IMAGE) |
| { |
| .name = BLOCK_OPT_STATIC, |
| .type = OPT_FLAG, |
| .help = "VDI static (pre-allocated) image" |
| }, |
| #endif |
| /* TODO: An additional option to set UUID values might be useful. */ |
| { NULL } |
| }; |
| |
| static BlockDriver bdrv_vdi = { |
| .format_name = "vdi", |
| .instance_size = sizeof(BDRVVdiState), |
| .bdrv_probe = vdi_probe, |
| .bdrv_open = vdi_open, |
| .bdrv_close = vdi_close, |
| .bdrv_create = vdi_create, |
| .bdrv_flush = vdi_flush, |
| .bdrv_is_allocated = vdi_is_allocated, |
| .bdrv_make_empty = vdi_make_empty, |
| |
| .bdrv_aio_readv = vdi_aio_readv, |
| #if defined(CONFIG_VDI_WRITE) |
| .bdrv_aio_writev = vdi_aio_writev, |
| #endif |
| |
| .bdrv_get_info = vdi_get_info, |
| |
| .create_options = vdi_create_options, |
| .bdrv_check = vdi_check, |
| }; |
| |
| static void bdrv_vdi_init(void) |
| { |
| logout("\n"); |
| bdrv_register(&bdrv_vdi); |
| } |
| |
| block_init(bdrv_vdi_init); |
