/* * 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) { /* TODO: additional checks possible. */ BDRVVdiState *s = (BDRVVdiState *)bs->opaque; int n_errors = 0; 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); } } else { fprintf(stderr, "ERROR: block index %" PRIu32 " too large, is %" PRIu32 "\n", block, bmap_entry); n_errors++; } } } 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); n_errors++; } qemu_free(bmap); return n_errors; } 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 void vdi_flush(BlockDriverState *bs) { logout("\n"); 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);