diff options
Diffstat (limited to 'src/block/vpc.c')
| -rw-r--r-- | src/block/vpc.c | 946 |
1 files changed, 946 insertions, 0 deletions
diff --git a/src/block/vpc.c b/src/block/vpc.c new file mode 100644 index 0000000..299d373 --- /dev/null +++ b/src/block/vpc.c @@ -0,0 +1,946 @@ +/* + * Block driver for Connectix / Microsoft Virtual PC images + * + * Copyright (c) 2005 Alex Beregszaszi + * Copyright (c) 2009 Kevin Wolf <kwolf@suse.de> + * + * 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-common.h" +#include "block/block_int.h" +#include "qemu/module.h" +#include "migration/migration.h" +#if defined(CONFIG_UUID) +#include <uuid/uuid.h> +#endif + +/**************************************************************/ + +#define HEADER_SIZE 512 + +//#define CACHE + +enum vhd_type { + VHD_FIXED = 2, + VHD_DYNAMIC = 3, + VHD_DIFFERENCING = 4, +}; + +// Seconds since Jan 1, 2000 0:00:00 (UTC) +#define VHD_TIMESTAMP_BASE 946684800 + +#define VHD_MAX_SECTORS (65535LL * 255 * 255) +#define VHD_MAX_GEOMETRY (65535LL * 16 * 255) + +// always big-endian +typedef struct vhd_footer { + char creator[8]; // "conectix" + uint32_t features; + uint32_t version; + + // Offset of next header structure, 0xFFFFFFFF if none + uint64_t data_offset; + + // Seconds since Jan 1, 2000 0:00:00 (UTC) + uint32_t timestamp; + + char creator_app[4]; // "vpc " + uint16_t major; + uint16_t minor; + char creator_os[4]; // "Wi2k" + + uint64_t orig_size; + uint64_t current_size; + + uint16_t cyls; + uint8_t heads; + uint8_t secs_per_cyl; + + uint32_t type; + + // Checksum of the Hard Disk Footer ("one's complement of the sum of all + // the bytes in the footer without the checksum field") + uint32_t checksum; + + // UUID used to identify a parent hard disk (backing file) + uint8_t uuid[16]; + + uint8_t in_saved_state; +} QEMU_PACKED VHDFooter; + +typedef struct vhd_dyndisk_header { + char magic[8]; // "cxsparse" + + // Offset of next header structure, 0xFFFFFFFF if none + uint64_t data_offset; + + // Offset of the Block Allocation Table (BAT) + uint64_t table_offset; + + uint32_t version; + uint32_t max_table_entries; // 32bit/entry + + // 2 MB by default, must be a power of two + uint32_t block_size; + + uint32_t checksum; + uint8_t parent_uuid[16]; + uint32_t parent_timestamp; + uint32_t reserved; + + // Backing file name (in UTF-16) + uint8_t parent_name[512]; + + struct { + uint32_t platform; + uint32_t data_space; + uint32_t data_length; + uint32_t reserved; + uint64_t data_offset; + } parent_locator[8]; +} QEMU_PACKED VHDDynDiskHeader; + +typedef struct BDRVVPCState { + CoMutex lock; + uint8_t footer_buf[HEADER_SIZE]; + uint64_t free_data_block_offset; + int max_table_entries; + uint32_t *pagetable; + uint64_t bat_offset; + uint64_t last_bitmap_offset; + + uint32_t block_size; + uint32_t bitmap_size; + +#ifdef CACHE + uint8_t *pageentry_u8; + uint32_t *pageentry_u32; + uint16_t *pageentry_u16; + + uint64_t last_bitmap; +#endif + + Error *migration_blocker; +} BDRVVPCState; + +static uint32_t vpc_checksum(uint8_t* buf, size_t size) +{ + uint32_t res = 0; + int i; + + for (i = 0; i < size; i++) + res += buf[i]; + + return ~res; +} + + +static int vpc_probe(const uint8_t *buf, int buf_size, const char *filename) +{ + if (buf_size >= 8 && !strncmp((char *)buf, "conectix", 8)) + return 100; + return 0; +} + +static int vpc_open(BlockDriverState *bs, QDict *options, int flags, + Error **errp) +{ + BDRVVPCState *s = bs->opaque; + int i; + VHDFooter *footer; + VHDDynDiskHeader *dyndisk_header; + uint8_t buf[HEADER_SIZE]; + uint32_t checksum; + uint64_t computed_size; + uint64_t pagetable_size; + int disk_type = VHD_DYNAMIC; + int ret; + + ret = bdrv_pread(bs->file->bs, 0, s->footer_buf, HEADER_SIZE); + if (ret < 0) { + goto fail; + } + + footer = (VHDFooter *) s->footer_buf; + if (strncmp(footer->creator, "conectix", 8)) { + int64_t offset = bdrv_getlength(bs->file->bs); + if (offset < 0) { + ret = offset; + goto fail; + } else if (offset < HEADER_SIZE) { + ret = -EINVAL; + goto fail; + } + + /* If a fixed disk, the footer is found only at the end of the file */ + ret = bdrv_pread(bs->file->bs, offset-HEADER_SIZE, s->footer_buf, + HEADER_SIZE); + if (ret < 0) { + goto fail; + } + if (strncmp(footer->creator, "conectix", 8)) { + error_setg(errp, "invalid VPC image"); + ret = -EINVAL; + goto fail; + } + disk_type = VHD_FIXED; + } + + checksum = be32_to_cpu(footer->checksum); + footer->checksum = 0; + if (vpc_checksum(s->footer_buf, HEADER_SIZE) != checksum) + fprintf(stderr, "block-vpc: The header checksum of '%s' is " + "incorrect.\n", bs->filename); + + /* Write 'checksum' back to footer, or else will leave it with zero. */ + footer->checksum = cpu_to_be32(checksum); + + // The visible size of a image in Virtual PC depends on the geometry + // rather than on the size stored in the footer (the size in the footer + // is too large usually) + bs->total_sectors = (int64_t) + be16_to_cpu(footer->cyls) * footer->heads * footer->secs_per_cyl; + + /* Images that have exactly the maximum geometry are probably bigger and + * would be truncated if we adhered to the geometry for them. Rely on + * footer->current_size for them. */ + if (bs->total_sectors == VHD_MAX_GEOMETRY) { + bs->total_sectors = be64_to_cpu(footer->current_size) / + BDRV_SECTOR_SIZE; + } + + /* Allow a maximum disk size of approximately 2 TB */ + if (bs->total_sectors >= VHD_MAX_SECTORS) { + ret = -EFBIG; + goto fail; + } + + if (disk_type == VHD_DYNAMIC) { + ret = bdrv_pread(bs->file->bs, be64_to_cpu(footer->data_offset), buf, + HEADER_SIZE); + if (ret < 0) { + goto fail; + } + + dyndisk_header = (VHDDynDiskHeader *) buf; + + if (strncmp(dyndisk_header->magic, "cxsparse", 8)) { + ret = -EINVAL; + goto fail; + } + + s->block_size = be32_to_cpu(dyndisk_header->block_size); + if (!is_power_of_2(s->block_size) || s->block_size < BDRV_SECTOR_SIZE) { + error_setg(errp, "Invalid block size %" PRIu32, s->block_size); + ret = -EINVAL; + goto fail; + } + s->bitmap_size = ((s->block_size / (8 * 512)) + 511) & ~511; + + s->max_table_entries = be32_to_cpu(dyndisk_header->max_table_entries); + + if ((bs->total_sectors * 512) / s->block_size > 0xffffffffU) { + ret = -EINVAL; + goto fail; + } + if (s->max_table_entries > (VHD_MAX_SECTORS * 512) / s->block_size) { + ret = -EINVAL; + goto fail; + } + + computed_size = (uint64_t) s->max_table_entries * s->block_size; + if (computed_size < bs->total_sectors * 512) { + ret = -EINVAL; + goto fail; + } + + if (s->max_table_entries > SIZE_MAX / 4 || + s->max_table_entries > (int) INT_MAX / 4) { + error_setg(errp, "Max Table Entries too large (%" PRId32 ")", + s->max_table_entries); + ret = -EINVAL; + goto fail; + } + + pagetable_size = (uint64_t) s->max_table_entries * 4; + + s->pagetable = qemu_try_blockalign(bs->file->bs, pagetable_size); + if (s->pagetable == NULL) { + ret = -ENOMEM; + goto fail; + } + + s->bat_offset = be64_to_cpu(dyndisk_header->table_offset); + + ret = bdrv_pread(bs->file->bs, s->bat_offset, s->pagetable, + pagetable_size); + if (ret < 0) { + goto fail; + } + + s->free_data_block_offset = + ROUND_UP(s->bat_offset + pagetable_size, 512); + + for (i = 0; i < s->max_table_entries; i++) { + be32_to_cpus(&s->pagetable[i]); + if (s->pagetable[i] != 0xFFFFFFFF) { + int64_t next = (512 * (int64_t) s->pagetable[i]) + + s->bitmap_size + s->block_size; + + if (next > s->free_data_block_offset) { + s->free_data_block_offset = next; + } + } + } + + if (s->free_data_block_offset > bdrv_getlength(bs->file->bs)) { + error_setg(errp, "block-vpc: free_data_block_offset points after " + "the end of file. The image has been truncated."); + ret = -EINVAL; + goto fail; + } + + s->last_bitmap_offset = (int64_t) -1; + +#ifdef CACHE + s->pageentry_u8 = g_malloc(512); + s->pageentry_u32 = s->pageentry_u8; + s->pageentry_u16 = s->pageentry_u8; + s->last_pagetable = -1; +#endif + } + + qemu_co_mutex_init(&s->lock); + + /* Disable migration when VHD images are used */ + error_setg(&s->migration_blocker, "The vpc format used by node '%s' " + "does not support live migration", + bdrv_get_device_or_node_name(bs)); + migrate_add_blocker(s->migration_blocker); + + return 0; + +fail: + qemu_vfree(s->pagetable); +#ifdef CACHE + g_free(s->pageentry_u8); +#endif + return ret; +} + +static int vpc_reopen_prepare(BDRVReopenState *state, + BlockReopenQueue *queue, Error **errp) +{ + return 0; +} + +/* + * Returns the absolute byte offset of the given sector in the image file. + * If the sector is not allocated, -1 is returned instead. + * + * The parameter write must be 1 if the offset will be used for a write + * operation (the block bitmaps is updated then), 0 otherwise. + */ +static inline int64_t get_sector_offset(BlockDriverState *bs, + int64_t sector_num, int write) +{ + BDRVVPCState *s = bs->opaque; + uint64_t offset = sector_num * 512; + uint64_t bitmap_offset, block_offset; + uint32_t pagetable_index, pageentry_index; + + pagetable_index = offset / s->block_size; + pageentry_index = (offset % s->block_size) / 512; + + if (pagetable_index >= s->max_table_entries || s->pagetable[pagetable_index] == 0xffffffff) + return -1; // not allocated + + bitmap_offset = 512 * (uint64_t) s->pagetable[pagetable_index]; + block_offset = bitmap_offset + s->bitmap_size + (512 * pageentry_index); + + // We must ensure that we don't write to any sectors which are marked as + // unused in the bitmap. We get away with setting all bits in the block + // bitmap each time we write to a new block. This might cause Virtual PC to + // miss sparse read optimization, but it's not a problem in terms of + // correctness. + if (write && (s->last_bitmap_offset != bitmap_offset)) { + uint8_t bitmap[s->bitmap_size]; + + s->last_bitmap_offset = bitmap_offset; + memset(bitmap, 0xff, s->bitmap_size); + bdrv_pwrite_sync(bs->file->bs, bitmap_offset, bitmap, s->bitmap_size); + } + + return block_offset; +} + +/* + * Writes the footer to the end of the image file. This is needed when the + * file grows as it overwrites the old footer + * + * Returns 0 on success and < 0 on error + */ +static int rewrite_footer(BlockDriverState* bs) +{ + int ret; + BDRVVPCState *s = bs->opaque; + int64_t offset = s->free_data_block_offset; + + ret = bdrv_pwrite_sync(bs->file->bs, offset, s->footer_buf, HEADER_SIZE); + if (ret < 0) + return ret; + + return 0; +} + +/* + * Allocates a new block. This involves writing a new footer and updating + * the Block Allocation Table to use the space at the old end of the image + * file (overwriting the old footer) + * + * Returns the sectors' offset in the image file on success and < 0 on error + */ +static int64_t alloc_block(BlockDriverState* bs, int64_t sector_num) +{ + BDRVVPCState *s = bs->opaque; + int64_t bat_offset; + uint32_t index, bat_value; + int ret; + uint8_t bitmap[s->bitmap_size]; + + // Check if sector_num is valid + if ((sector_num < 0) || (sector_num > bs->total_sectors)) + return -1; + + // Write entry into in-memory BAT + index = (sector_num * 512) / s->block_size; + if (s->pagetable[index] != 0xFFFFFFFF) + return -1; + + s->pagetable[index] = s->free_data_block_offset / 512; + + // Initialize the block's bitmap + memset(bitmap, 0xff, s->bitmap_size); + ret = bdrv_pwrite_sync(bs->file->bs, s->free_data_block_offset, bitmap, + s->bitmap_size); + if (ret < 0) { + return ret; + } + + // Write new footer (the old one will be overwritten) + s->free_data_block_offset += s->block_size + s->bitmap_size; + ret = rewrite_footer(bs); + if (ret < 0) + goto fail; + + // Write BAT entry to disk + bat_offset = s->bat_offset + (4 * index); + bat_value = cpu_to_be32(s->pagetable[index]); + ret = bdrv_pwrite_sync(bs->file->bs, bat_offset, &bat_value, 4); + if (ret < 0) + goto fail; + + return get_sector_offset(bs, sector_num, 0); + +fail: + s->free_data_block_offset -= (s->block_size + s->bitmap_size); + return -1; +} + +static int vpc_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) +{ + BDRVVPCState *s = (BDRVVPCState *)bs->opaque; + VHDFooter *footer = (VHDFooter *) s->footer_buf; + + if (be32_to_cpu(footer->type) != VHD_FIXED) { + bdi->cluster_size = s->block_size; + } + + bdi->unallocated_blocks_are_zero = true; + return 0; +} + +static int vpc_read(BlockDriverState *bs, int64_t sector_num, + uint8_t *buf, int nb_sectors) +{ + BDRVVPCState *s = bs->opaque; + int ret; + int64_t offset; + int64_t sectors, sectors_per_block; + VHDFooter *footer = (VHDFooter *) s->footer_buf; + + if (be32_to_cpu(footer->type) == VHD_FIXED) { + return bdrv_read(bs->file->bs, sector_num, buf, nb_sectors); + } + while (nb_sectors > 0) { + offset = get_sector_offset(bs, sector_num, 0); + + sectors_per_block = s->block_size >> BDRV_SECTOR_BITS; + sectors = sectors_per_block - (sector_num % sectors_per_block); + if (sectors > nb_sectors) { + sectors = nb_sectors; + } + + if (offset == -1) { + memset(buf, 0, sectors * BDRV_SECTOR_SIZE); + } else { + ret = bdrv_pread(bs->file->bs, offset, buf, + sectors * BDRV_SECTOR_SIZE); + if (ret != sectors * BDRV_SECTOR_SIZE) { + return -1; + } + } + + nb_sectors -= sectors; + sector_num += sectors; + buf += sectors * BDRV_SECTOR_SIZE; + } + return 0; +} + +static coroutine_fn int vpc_co_read(BlockDriverState *bs, int64_t sector_num, + uint8_t *buf, int nb_sectors) +{ + int ret; + BDRVVPCState *s = bs->opaque; + qemu_co_mutex_lock(&s->lock); + ret = vpc_read(bs, sector_num, buf, nb_sectors); + qemu_co_mutex_unlock(&s->lock); + return ret; +} + +static int vpc_write(BlockDriverState *bs, int64_t sector_num, + const uint8_t *buf, int nb_sectors) +{ + BDRVVPCState *s = bs->opaque; + int64_t offset; + int64_t sectors, sectors_per_block; + int ret; + VHDFooter *footer = (VHDFooter *) s->footer_buf; + + if (be32_to_cpu(footer->type) == VHD_FIXED) { + return bdrv_write(bs->file->bs, sector_num, buf, nb_sectors); + } + while (nb_sectors > 0) { + offset = get_sector_offset(bs, sector_num, 1); + + sectors_per_block = s->block_size >> BDRV_SECTOR_BITS; + sectors = sectors_per_block - (sector_num % sectors_per_block); + if (sectors > nb_sectors) { + sectors = nb_sectors; + } + + if (offset == -1) { + offset = alloc_block(bs, sector_num); + if (offset < 0) + return -1; + } + + ret = bdrv_pwrite(bs->file->bs, offset, buf, + sectors * BDRV_SECTOR_SIZE); + if (ret != sectors * BDRV_SECTOR_SIZE) { + return -1; + } + + nb_sectors -= sectors; + sector_num += sectors; + buf += sectors * BDRV_SECTOR_SIZE; + } + + return 0; +} + +static coroutine_fn int vpc_co_write(BlockDriverState *bs, int64_t sector_num, + const uint8_t *buf, int nb_sectors) +{ + int ret; + BDRVVPCState *s = bs->opaque; + qemu_co_mutex_lock(&s->lock); + ret = vpc_write(bs, sector_num, buf, nb_sectors); + qemu_co_mutex_unlock(&s->lock); + return ret; +} + +static int64_t coroutine_fn vpc_co_get_block_status(BlockDriverState *bs, + int64_t sector_num, int nb_sectors, int *pnum) +{ + BDRVVPCState *s = bs->opaque; + VHDFooter *footer = (VHDFooter*) s->footer_buf; + int64_t start, offset; + bool allocated; + int n; + + if (be32_to_cpu(footer->type) == VHD_FIXED) { + *pnum = nb_sectors; + return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID | BDRV_BLOCK_DATA | + (sector_num << BDRV_SECTOR_BITS); + } + + offset = get_sector_offset(bs, sector_num, 0); + start = offset; + allocated = (offset != -1); + *pnum = 0; + + do { + /* All sectors in a block are contiguous (without using the bitmap) */ + n = ROUND_UP(sector_num + 1, s->block_size / BDRV_SECTOR_SIZE) + - sector_num; + n = MIN(n, nb_sectors); + + *pnum += n; + sector_num += n; + nb_sectors -= n; + /* *pnum can't be greater than one block for allocated + * sectors since there is always a bitmap in between. */ + if (allocated) { + return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | start; + } + if (nb_sectors == 0) { + break; + } + offset = get_sector_offset(bs, sector_num, 0); + } while (offset == -1); + + return 0; +} + +/* + * Calculates the number of cylinders, heads and sectors per cylinder + * based on a given number of sectors. This is the algorithm described + * in the VHD specification. + * + * Note that the geometry doesn't always exactly match total_sectors but + * may round it down. + * + * Returns 0 on success, -EFBIG if the size is larger than ~2 TB. Override + * the hardware EIDE and ATA-2 limit of 16 heads (max disk size of 127 GB) + * and instead allow up to 255 heads. + */ +static int calculate_geometry(int64_t total_sectors, uint16_t* cyls, + uint8_t* heads, uint8_t* secs_per_cyl) +{ + uint32_t cyls_times_heads; + + total_sectors = MIN(total_sectors, VHD_MAX_GEOMETRY); + + if (total_sectors >= 65535LL * 16 * 63) { + *secs_per_cyl = 255; + *heads = 16; + cyls_times_heads = total_sectors / *secs_per_cyl; + } else { + *secs_per_cyl = 17; + cyls_times_heads = total_sectors / *secs_per_cyl; + *heads = (cyls_times_heads + 1023) / 1024; + + if (*heads < 4) { + *heads = 4; + } + + if (cyls_times_heads >= (*heads * 1024) || *heads > 16) { + *secs_per_cyl = 31; + *heads = 16; + cyls_times_heads = total_sectors / *secs_per_cyl; + } + + if (cyls_times_heads >= (*heads * 1024)) { + *secs_per_cyl = 63; + *heads = 16; + cyls_times_heads = total_sectors / *secs_per_cyl; + } + } + + *cyls = cyls_times_heads / *heads; + + return 0; +} + +static int create_dynamic_disk(BlockDriverState *bs, uint8_t *buf, + int64_t total_sectors) +{ + VHDDynDiskHeader *dyndisk_header = + (VHDDynDiskHeader *) buf; + size_t block_size, num_bat_entries; + int i; + int ret; + int64_t offset = 0; + + // Write the footer (twice: at the beginning and at the end) + block_size = 0x200000; + num_bat_entries = (total_sectors + block_size / 512) / (block_size / 512); + + ret = bdrv_pwrite_sync(bs, offset, buf, HEADER_SIZE); + if (ret) { + goto fail; + } + + offset = 1536 + ((num_bat_entries * 4 + 511) & ~511); + ret = bdrv_pwrite_sync(bs, offset, buf, HEADER_SIZE); + if (ret < 0) { + goto fail; + } + + // Write the initial BAT + offset = 3 * 512; + + memset(buf, 0xFF, 512); + for (i = 0; i < (num_bat_entries * 4 + 511) / 512; i++) { + ret = bdrv_pwrite_sync(bs, offset, buf, 512); + if (ret < 0) { + goto fail; + } + offset += 512; + } + + // Prepare the Dynamic Disk Header + memset(buf, 0, 1024); + + memcpy(dyndisk_header->magic, "cxsparse", 8); + + /* + * Note: The spec is actually wrong here for data_offset, it says + * 0xFFFFFFFF, but MS tools expect all 64 bits to be set. + */ + dyndisk_header->data_offset = cpu_to_be64(0xFFFFFFFFFFFFFFFFULL); + dyndisk_header->table_offset = cpu_to_be64(3 * 512); + dyndisk_header->version = cpu_to_be32(0x00010000); + dyndisk_header->block_size = cpu_to_be32(block_size); + dyndisk_header->max_table_entries = cpu_to_be32(num_bat_entries); + + dyndisk_header->checksum = cpu_to_be32(vpc_checksum(buf, 1024)); + + // Write the header + offset = 512; + + ret = bdrv_pwrite_sync(bs, offset, buf, 1024); + if (ret < 0) { + goto fail; + } + + fail: + return ret; +} + +static int create_fixed_disk(BlockDriverState *bs, uint8_t *buf, + int64_t total_size) +{ + int ret; + + /* Add footer to total size */ + total_size += HEADER_SIZE; + + ret = bdrv_truncate(bs, total_size); + if (ret < 0) { + return ret; + } + + ret = bdrv_pwrite_sync(bs, total_size - HEADER_SIZE, buf, HEADER_SIZE); + if (ret < 0) { + return ret; + } + + return ret; +} + +static int vpc_create(const char *filename, QemuOpts *opts, Error **errp) +{ + uint8_t buf[1024]; + VHDFooter *footer = (VHDFooter *) buf; + char *disk_type_param; + int i; + uint16_t cyls = 0; + uint8_t heads = 0; + uint8_t secs_per_cyl = 0; + int64_t total_sectors; + int64_t total_size; + int disk_type; + int ret = -EIO; + Error *local_err = NULL; + BlockDriverState *bs = NULL; + + /* Read out options */ + total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), + BDRV_SECTOR_SIZE); + disk_type_param = qemu_opt_get_del(opts, BLOCK_OPT_SUBFMT); + if (disk_type_param) { + if (!strcmp(disk_type_param, "dynamic")) { + disk_type = VHD_DYNAMIC; + } else if (!strcmp(disk_type_param, "fixed")) { + disk_type = VHD_FIXED; + } else { + ret = -EINVAL; + goto out; + } + } else { + disk_type = VHD_DYNAMIC; + } + + ret = bdrv_create_file(filename, opts, &local_err); + if (ret < 0) { + error_propagate(errp, local_err); + goto out; + } + ret = bdrv_open(&bs, filename, NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL, + &local_err); + if (ret < 0) { + error_propagate(errp, local_err); + goto out; + } + + /* + * Calculate matching total_size and geometry. Increase the number of + * sectors requested until we get enough (or fail). This ensures that + * qemu-img convert doesn't truncate images, but rather rounds up. + * + * If the image size can't be represented by a spec conform CHS geometry, + * we set the geometry to 65535 x 16 x 255 (CxHxS) sectors and use + * the image size from the VHD footer to calculate total_sectors. + */ + total_sectors = MIN(VHD_MAX_GEOMETRY, total_size / BDRV_SECTOR_SIZE); + for (i = 0; total_sectors > (int64_t)cyls * heads * secs_per_cyl; i++) { + calculate_geometry(total_sectors + i, &cyls, &heads, &secs_per_cyl); + } + + if ((int64_t)cyls * heads * secs_per_cyl == VHD_MAX_GEOMETRY) { + total_sectors = total_size / BDRV_SECTOR_SIZE; + /* Allow a maximum disk size of approximately 2 TB */ + if (total_sectors > VHD_MAX_SECTORS) { + ret = -EFBIG; + goto out; + } + } else { + total_sectors = (int64_t)cyls * heads * secs_per_cyl; + total_size = total_sectors * BDRV_SECTOR_SIZE; + } + + /* Prepare the Hard Disk Footer */ + memset(buf, 0, 1024); + + memcpy(footer->creator, "conectix", 8); + /* TODO Check if "qemu" creator_app is ok for VPC */ + memcpy(footer->creator_app, "qemu", 4); + memcpy(footer->creator_os, "Wi2k", 4); + + footer->features = cpu_to_be32(0x02); + footer->version = cpu_to_be32(0x00010000); + if (disk_type == VHD_DYNAMIC) { + footer->data_offset = cpu_to_be64(HEADER_SIZE); + } else { + footer->data_offset = cpu_to_be64(0xFFFFFFFFFFFFFFFFULL); + } + footer->timestamp = cpu_to_be32(time(NULL) - VHD_TIMESTAMP_BASE); + + /* Version of Virtual PC 2007 */ + footer->major = cpu_to_be16(0x0005); + footer->minor = cpu_to_be16(0x0003); + footer->orig_size = cpu_to_be64(total_size); + footer->current_size = cpu_to_be64(total_size); + footer->cyls = cpu_to_be16(cyls); + footer->heads = heads; + footer->secs_per_cyl = secs_per_cyl; + + footer->type = cpu_to_be32(disk_type); + +#if defined(CONFIG_UUID) + uuid_generate(footer->uuid); +#endif + + footer->checksum = cpu_to_be32(vpc_checksum(buf, HEADER_SIZE)); + + if (disk_type == VHD_DYNAMIC) { + ret = create_dynamic_disk(bs, buf, total_sectors); + } else { + ret = create_fixed_disk(bs, buf, total_size); + } + +out: + bdrv_unref(bs); + g_free(disk_type_param); + return ret; +} + +static int vpc_has_zero_init(BlockDriverState *bs) +{ + BDRVVPCState *s = bs->opaque; + VHDFooter *footer = (VHDFooter *) s->footer_buf; + + if (be32_to_cpu(footer->type) == VHD_FIXED) { + return bdrv_has_zero_init(bs->file->bs); + } else { + return 1; + } +} + +static void vpc_close(BlockDriverState *bs) +{ + BDRVVPCState *s = bs->opaque; + qemu_vfree(s->pagetable); +#ifdef CACHE + g_free(s->pageentry_u8); +#endif + + migrate_del_blocker(s->migration_blocker); + error_free(s->migration_blocker); +} + +static QemuOptsList vpc_create_opts = { + .name = "vpc-create-opts", + .head = QTAILQ_HEAD_INITIALIZER(vpc_create_opts.head), + .desc = { + { + .name = BLOCK_OPT_SIZE, + .type = QEMU_OPT_SIZE, + .help = "Virtual disk size" + }, + { + .name = BLOCK_OPT_SUBFMT, + .type = QEMU_OPT_STRING, + .help = + "Type of virtual hard disk format. Supported formats are " + "{dynamic (default) | fixed} " + }, + { /* end of list */ } + } +}; + +static BlockDriver bdrv_vpc = { + .format_name = "vpc", + .instance_size = sizeof(BDRVVPCState), + + .bdrv_probe = vpc_probe, + .bdrv_open = vpc_open, + .bdrv_close = vpc_close, + .bdrv_reopen_prepare = vpc_reopen_prepare, + .bdrv_create = vpc_create, + + .bdrv_read = vpc_co_read, + .bdrv_write = vpc_co_write, + .bdrv_co_get_block_status = vpc_co_get_block_status, + + .bdrv_get_info = vpc_get_info, + + .create_opts = &vpc_create_opts, + .bdrv_has_zero_init = vpc_has_zero_init, +}; + +static void bdrv_vpc_init(void) +{ + bdrv_register(&bdrv_vpc); +} + +block_init(bdrv_vpc_init); |
