diff options
Diffstat (limited to 'qemu/block/vdi.c')
-rw-r--r-- | qemu/block/vdi.c | 923 |
1 files changed, 0 insertions, 923 deletions
diff --git a/qemu/block/vdi.c b/qemu/block/vdi.c deleted file mode 100644 index 75d4819ed..000000000 --- a/qemu/block/vdi.c +++ /dev/null @@ -1,923 +0,0 @@ -/* - * Block driver for the Virtual Disk Image (VDI) format - * - * Copyright (c) 2009, 2012 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 adjacent 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/osdep.h" -#include "qapi/error.h" -#include "block/block_int.h" -#include "sysemu/block-backend.h" -#include "qemu/module.h" -#include "migration/migration.h" -#include "qemu/coroutine.h" -#include "qemu/cutils.h" - -#if defined(CONFIG_UUID) -#include <uuid/uuid.h> -#else -/* TODO: move uuid emulation to some central place in QEMU. */ -#include "sysemu/sysemu.h" /* UUID_FMT */ -typedef unsigned char uuid_t[16]; -#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 -#define DEFAULT_CLUSTER_SIZE (1 * MiB) - -#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" - -/* A never-allocated block; semantically arbitrary content. */ -#define VDI_UNALLOCATED 0xffffffffU - -/* A discarded (no longer allocated) block; semantically zero-filled. */ -#define VDI_DISCARDED 0xfffffffeU - -#define VDI_IS_ALLOCATED(X) ((X) < VDI_DISCARDED) - -/* The bmap will take up VDI_BLOCKS_IN_IMAGE_MAX * sizeof(uint32_t) bytes; since - * the bmap is read and written in a single operation, its size needs to be - * limited to INT_MAX; furthermore, when opening an image, the bmap size is - * rounded up to be aligned on BDRV_SECTOR_SIZE. - * Therefore this should satisfy the following: - * VDI_BLOCKS_IN_IMAGE_MAX * sizeof(uint32_t) + BDRV_SECTOR_SIZE == INT_MAX + 1 - * (INT_MAX + 1 is the first value not representable as an int) - * This guarantees that any value below or equal to the constant will, when - * multiplied by sizeof(uint32_t) and rounded up to a BDRV_SECTOR_SIZE boundary, - * still be below or equal to INT_MAX. */ -#define VDI_BLOCKS_IN_IMAGE_MAX \ - ((unsigned)((INT_MAX + 1u - BDRV_SECTOR_SIZE) / sizeof(uint32_t))) -#define VDI_DISK_SIZE_MAX ((uint64_t)VDI_BLOCKS_IN_IMAGE_MAX * \ - (uint64_t)DEFAULT_CLUSTER_SIZE) - -#if !defined(CONFIG_UUID) -static inline void uuid_generate(uuid_t out) -{ - memset(out, 0, sizeof(uuid_t)); -} - -static inline int uuid_is_null(const uuid_t uu) -{ - uuid_t null_uuid = { 0 }; - return memcmp(uu, null_uuid, sizeof(uuid_t)) == 0; -} - -# if defined(CONFIG_VDI_DEBUG) -static inline 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 -#endif - -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]; -} QEMU_PACKED VdiHeader; - -typedef struct { - /* 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 endianness). */ - VdiHeader header; - - CoMutex write_lock; - - Error *migration_blocker; -} 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); - 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%08x\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, - BdrvCheckMode fix) -{ - /* TODO: additional checks possible. */ - BDRVVdiState *s = (BDRVVdiState *)bs->opaque; - uint32_t blocks_allocated = 0; - uint32_t block; - uint32_t *bmap; - logout("\n"); - - if (fix) { - return -ENOTSUP; - } - - bmap = g_try_new(uint32_t, s->header.blocks_in_image); - if (s->header.blocks_in_image && bmap == NULL) { - res->check_errors++; - return -ENOMEM; - } - - 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 (VDI_IS_ALLOCATED(bmap_entry)) { - if (bmap_entry < s->header.blocks_in_image) { - blocks_allocated++; - if (!VDI_IS_ALLOCATED(bmap[bmap_entry])) { - 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++; - } - - g_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; - bdi->unallocated_blocks_are_zero = true; - 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 ret = 0; - - logout("\n"); - - if (buf_size < sizeof(*header)) { - /* Header too small, no VDI. */ - } else if (le32_to_cpu(header->signature) == VDI_SIGNATURE) { - ret = 100; - } - - if (ret == 0) { - logout("no vdi image\n"); - } else { - logout("%s", header->text); - } - - return ret; -} - -static int vdi_open(BlockDriverState *bs, QDict *options, int flags, - Error **errp) -{ - BDRVVdiState *s = bs->opaque; - VdiHeader header; - size_t bmap_size; - int ret; - - logout("\n"); - - ret = bdrv_read(bs->file->bs, 0, (uint8_t *)&header, 1); - if (ret < 0) { - goto fail; - } - - vdi_header_to_cpu(&header); -#if defined(CONFIG_VDI_DEBUG) - vdi_header_print(&header); -#endif - - if (header.disk_size > VDI_DISK_SIZE_MAX) { - error_setg(errp, "Unsupported VDI image size (size is 0x%" PRIx64 - ", max supported is 0x%" PRIx64 ")", - header.disk_size, VDI_DISK_SIZE_MAX); - ret = -ENOTSUP; - goto fail; - } - - 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 = ROUND_UP(header.disk_size, SECTOR_SIZE); - } - - if (header.signature != VDI_SIGNATURE) { - error_setg(errp, "Image not in VDI format (bad signature %08" PRIx32 - ")", header.signature); - ret = -EINVAL; - goto fail; - } else if (header.version != VDI_VERSION_1_1) { - error_setg(errp, "unsupported VDI image (version %" PRIu32 ".%" PRIu32 - ")", header.version >> 16, header.version & 0xffff); - ret = -ENOTSUP; - goto fail; - } else if (header.offset_bmap % SECTOR_SIZE != 0) { - /* We only support block maps which start on a sector boundary. */ - error_setg(errp, "unsupported VDI image (unaligned block map offset " - "0x%" PRIx32 ")", header.offset_bmap); - ret = -ENOTSUP; - goto fail; - } else if (header.offset_data % SECTOR_SIZE != 0) { - /* We only support data blocks which start on a sector boundary. */ - error_setg(errp, "unsupported VDI image (unaligned data offset 0x%" - PRIx32 ")", header.offset_data); - ret = -ENOTSUP; - goto fail; - } else if (header.sector_size != SECTOR_SIZE) { - error_setg(errp, "unsupported VDI image (sector size %" PRIu32 - " is not %u)", header.sector_size, SECTOR_SIZE); - ret = -ENOTSUP; - goto fail; - } else if (header.block_size != DEFAULT_CLUSTER_SIZE) { - error_setg(errp, "unsupported VDI image (block size %" PRIu32 - " is not %u)", header.block_size, DEFAULT_CLUSTER_SIZE); - ret = -ENOTSUP; - goto fail; - } else if (header.disk_size > - (uint64_t)header.blocks_in_image * header.block_size) { - error_setg(errp, "unsupported VDI image (disk size %" PRIu64 ", " - "image bitmap has room for %" PRIu64 ")", - header.disk_size, - (uint64_t)header.blocks_in_image * header.block_size); - ret = -ENOTSUP; - goto fail; - } else if (!uuid_is_null(header.uuid_link)) { - error_setg(errp, "unsupported VDI image (non-NULL link UUID)"); - ret = -ENOTSUP; - goto fail; - } else if (!uuid_is_null(header.uuid_parent)) { - error_setg(errp, "unsupported VDI image (non-NULL parent UUID)"); - ret = -ENOTSUP; - goto fail; - } else if (header.blocks_in_image > VDI_BLOCKS_IN_IMAGE_MAX) { - error_setg(errp, "unsupported VDI image " - "(too many blocks %u, max is %u)", - header.blocks_in_image, VDI_BLOCKS_IN_IMAGE_MAX); - ret = -ENOTSUP; - 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 = DIV_ROUND_UP(bmap_size, SECTOR_SIZE); - s->bmap = qemu_try_blockalign(bs->file->bs, bmap_size * SECTOR_SIZE); - if (s->bmap == NULL) { - ret = -ENOMEM; - goto fail; - } - - ret = bdrv_read(bs->file->bs, s->bmap_sector, (uint8_t *)s->bmap, - bmap_size); - if (ret < 0) { - goto fail_free_bmap; - } - - /* Disable migration when vdi images are used */ - error_setg(&s->migration_blocker, "The vdi format used by node '%s' " - "does not support live migration", - bdrv_get_device_or_node_name(bs)); - migrate_add_blocker(s->migration_blocker); - - qemu_co_mutex_init(&s->write_lock); - - return 0; - - fail_free_bmap: - qemu_vfree(s->bmap); - - fail: - return ret; -} - -static int vdi_reopen_prepare(BDRVReopenState *state, - BlockReopenQueue *queue, Error **errp) -{ - return 0; -} - -static int64_t coroutine_fn vdi_co_get_block_status(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, int *pnum, BlockDriverState **file) -{ - /* 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]); - uint64_t offset; - int result; - - logout("%p, %" PRId64 ", %d, %p\n", bs, sector_num, nb_sectors, pnum); - if (n_sectors > nb_sectors) { - n_sectors = nb_sectors; - } - *pnum = n_sectors; - result = VDI_IS_ALLOCATED(bmap_entry); - if (!result) { - return 0; - } - - offset = s->header.offset_data + - (uint64_t)bmap_entry * s->block_size + - sector_in_block * SECTOR_SIZE; - *file = bs->file->bs; - return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | offset; -} - -static int vdi_co_read(BlockDriverState *bs, - int64_t sector_num, uint8_t *buf, int nb_sectors) -{ - BDRVVdiState *s = bs->opaque; - uint32_t bmap_entry; - uint32_t block_index; - uint32_t sector_in_block; - uint32_t n_sectors; - int ret = 0; - - logout("\n"); - - while (ret >= 0 && nb_sectors > 0) { - block_index = sector_num / s->block_sectors; - sector_in_block = sector_num % s->block_sectors; - n_sectors = s->block_sectors - sector_in_block; - if (n_sectors > nb_sectors) { - n_sectors = nb_sectors; - } - - logout("will read %u sectors starting at sector %" PRIu64 "\n", - n_sectors, sector_num); - - /* prepare next AIO request */ - bmap_entry = le32_to_cpu(s->bmap[block_index]); - if (!VDI_IS_ALLOCATED(bmap_entry)) { - /* Block not allocated, return zeros, no need to wait. */ - memset(buf, 0, n_sectors * SECTOR_SIZE); - ret = 0; - } else { - uint64_t offset = s->header.offset_data / SECTOR_SIZE + - (uint64_t)bmap_entry * s->block_sectors + - sector_in_block; - ret = bdrv_read(bs->file->bs, offset, buf, n_sectors); - } - logout("%u sectors read\n", n_sectors); - - nb_sectors -= n_sectors; - sector_num += n_sectors; - buf += n_sectors * SECTOR_SIZE; - } - - return ret; -} - -static int vdi_co_write(BlockDriverState *bs, - int64_t sector_num, const uint8_t *buf, int nb_sectors) -{ - BDRVVdiState *s = bs->opaque; - uint32_t bmap_entry; - uint32_t block_index; - uint32_t sector_in_block; - uint32_t n_sectors; - uint32_t bmap_first = VDI_UNALLOCATED; - uint32_t bmap_last = VDI_UNALLOCATED; - uint8_t *block = NULL; - int ret = 0; - - logout("\n"); - - while (ret >= 0 && nb_sectors > 0) { - block_index = sector_num / s->block_sectors; - sector_in_block = sector_num % s->block_sectors; - n_sectors = s->block_sectors - sector_in_block; - if (n_sectors > nb_sectors) { - n_sectors = nb_sectors; - } - - logout("will write %u sectors starting at sector %" PRIu64 "\n", - n_sectors, sector_num); - - /* prepare next AIO request */ - bmap_entry = le32_to_cpu(s->bmap[block_index]); - if (!VDI_IS_ALLOCATED(bmap_entry)) { - /* Allocate new block and write to it. */ - uint64_t offset; - 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; - if (block == NULL) { - block = g_malloc(s->block_size); - bmap_first = block_index; - } - bmap_last = block_index; - /* Copy data to be written to new block and zero unused parts. */ - memset(block, 0, sector_in_block * SECTOR_SIZE); - memcpy(block + sector_in_block * SECTOR_SIZE, - buf, n_sectors * SECTOR_SIZE); - memset(block + (sector_in_block + n_sectors) * SECTOR_SIZE, 0, - (s->block_sectors - n_sectors - sector_in_block) * SECTOR_SIZE); - - /* Note that this coroutine does not yield anywhere from reading the - * bmap entry until here, so in regards to all the coroutines trying - * to write to this cluster, the one doing the allocation will - * always be the first to try to acquire the lock. - * Therefore, it is also the first that will actually be able to - * acquire the lock and thus the padded cluster is written before - * the other coroutines can write to the affected area. */ - qemu_co_mutex_lock(&s->write_lock); - ret = bdrv_write(bs->file->bs, offset, block, s->block_sectors); - qemu_co_mutex_unlock(&s->write_lock); - } else { - uint64_t offset = s->header.offset_data / SECTOR_SIZE + - (uint64_t)bmap_entry * s->block_sectors + - sector_in_block; - qemu_co_mutex_lock(&s->write_lock); - /* This lock is only used to make sure the following write operation - * is executed after the write issued by the coroutine allocating - * this cluster, therefore we do not need to keep it locked. - * As stated above, the allocating coroutine will always try to lock - * the mutex before all the other concurrent accesses to that - * cluster, therefore at this point we can be absolutely certain - * that that write operation has returned (there may be other writes - * in flight, but they do not concern this very operation). */ - qemu_co_mutex_unlock(&s->write_lock); - ret = bdrv_write(bs->file->bs, offset, buf, n_sectors); - } - - nb_sectors -= n_sectors; - sector_num += n_sectors; - buf += n_sectors * SECTOR_SIZE; - - logout("%u sectors written\n", n_sectors); - } - - logout("finished data write\n"); - if (ret < 0) { - return ret; - } - - if (block) { - /* One or more new blocks were allocated. */ - VdiHeader *header = (VdiHeader *) block; - uint8_t *base; - uint64_t offset; - - logout("now writing modified header\n"); - assert(VDI_IS_ALLOCATED(bmap_first)); - *header = s->header; - vdi_header_to_le(header); - ret = bdrv_write(bs->file->bs, 0, block, 1); - g_free(block); - block = NULL; - - if (ret < 0) { - return ret; - } - - 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; - base = ((uint8_t *)&s->bmap[0]) + bmap_first * SECTOR_SIZE; - logout("will write %u block map sectors starting from entry %u\n", - n_sectors, bmap_first); - ret = bdrv_write(bs->file->bs, offset, base, n_sectors); - } - - return ret; -} - -static int vdi_create(const char *filename, QemuOpts *opts, Error **errp) -{ - int ret = 0; - uint64_t bytes = 0; - uint32_t blocks; - size_t block_size = DEFAULT_CLUSTER_SIZE; - uint32_t image_type = VDI_TYPE_DYNAMIC; - VdiHeader header; - size_t i; - size_t bmap_size; - int64_t offset = 0; - Error *local_err = NULL; - BlockBackend *blk = NULL; - uint32_t *bmap = NULL; - - logout("\n"); - - /* Read out options. */ - bytes = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), - BDRV_SECTOR_SIZE); -#if defined(CONFIG_VDI_BLOCK_SIZE) - /* TODO: Additional checks (SECTOR_SIZE * 2^n, ...). */ - block_size = qemu_opt_get_size_del(opts, - BLOCK_OPT_CLUSTER_SIZE, - DEFAULT_CLUSTER_SIZE); -#endif -#if defined(CONFIG_VDI_STATIC_IMAGE) - if (qemu_opt_get_bool_del(opts, BLOCK_OPT_STATIC, false)) { - image_type = VDI_TYPE_STATIC; - } -#endif - - if (bytes > VDI_DISK_SIZE_MAX) { - ret = -ENOTSUP; - error_setg(errp, "Unsupported VDI image size (size is 0x%" PRIx64 - ", max supported is 0x%" PRIx64 ")", - bytes, VDI_DISK_SIZE_MAX); - goto exit; - } - - ret = bdrv_create_file(filename, opts, &local_err); - if (ret < 0) { - error_propagate(errp, local_err); - goto exit; - } - - blk = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err); - if (blk == NULL) { - error_propagate(errp, local_err); - ret = -EIO; - goto exit; - } - - blk_set_allow_write_beyond_eof(blk, true); - - /* We need enough blocks to store the given disk size, - so always round up. */ - blocks = DIV_ROUND_UP(bytes, block_size); - - bmap_size = blocks * sizeof(uint32_t); - bmap_size = ROUND_UP(bmap_size, SECTOR_SIZE); - - 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); - ret = blk_pwrite(blk, offset, &header, sizeof(header)); - if (ret < 0) { - error_setg(errp, "Error writing header to %s", filename); - goto exit; - } - offset += sizeof(header); - - if (bmap_size > 0) { - bmap = g_try_malloc0(bmap_size); - if (bmap == NULL) { - ret = -ENOMEM; - error_setg(errp, "Could not allocate bmap"); - goto exit; - } - for (i = 0; i < blocks; i++) { - if (image_type == VDI_TYPE_STATIC) { - bmap[i] = i; - } else { - bmap[i] = VDI_UNALLOCATED; - } - } - ret = blk_pwrite(blk, offset, bmap, bmap_size); - if (ret < 0) { - error_setg(errp, "Error writing bmap to %s", filename); - goto exit; - } - offset += bmap_size; - } - - if (image_type == VDI_TYPE_STATIC) { - ret = blk_truncate(blk, offset + blocks * block_size); - if (ret < 0) { - error_setg(errp, "Failed to statically allocate %s", filename); - goto exit; - } - } - -exit: - blk_unref(blk); - g_free(bmap); - return ret; -} - -static void vdi_close(BlockDriverState *bs) -{ - BDRVVdiState *s = bs->opaque; - - qemu_vfree(s->bmap); - - migrate_del_blocker(s->migration_blocker); - error_free(s->migration_blocker); -} - -static QemuOptsList vdi_create_opts = { - .name = "vdi-create-opts", - .head = QTAILQ_HEAD_INITIALIZER(vdi_create_opts.head), - .desc = { - { - .name = BLOCK_OPT_SIZE, - .type = QEMU_OPT_SIZE, - .help = "Virtual disk size" - }, -#if defined(CONFIG_VDI_BLOCK_SIZE) - { - .name = BLOCK_OPT_CLUSTER_SIZE, - .type = QEMU_OPT_SIZE, - .help = "VDI cluster (block) size", - .def_value_str = stringify(DEFAULT_CLUSTER_SIZE) - }, -#endif -#if defined(CONFIG_VDI_STATIC_IMAGE) - { - .name = BLOCK_OPT_STATIC, - .type = QEMU_OPT_BOOL, - .help = "VDI static (pre-allocated) image", - .def_value_str = "off" - }, -#endif - /* TODO: An additional option to set UUID values might be useful. */ - { /* end of list */ } - } -}; - -static BlockDriver bdrv_vdi = { - .format_name = "vdi", - .instance_size = sizeof(BDRVVdiState), - .bdrv_probe = vdi_probe, - .bdrv_open = vdi_open, - .bdrv_close = vdi_close, - .bdrv_reopen_prepare = vdi_reopen_prepare, - .bdrv_create = vdi_create, - .bdrv_has_zero_init = bdrv_has_zero_init_1, - .bdrv_co_get_block_status = vdi_co_get_block_status, - .bdrv_make_empty = vdi_make_empty, - - .bdrv_read = vdi_co_read, -#if defined(CONFIG_VDI_WRITE) - .bdrv_write = vdi_co_write, -#endif - - .bdrv_get_info = vdi_get_info, - - .create_opts = &vdi_create_opts, - .bdrv_check = vdi_check, -}; - -static void bdrv_vdi_init(void) -{ - logout("\n"); - bdrv_register(&bdrv_vdi); -} - -block_init(bdrv_vdi_init); |