diff options
Diffstat (limited to 'qemu/block/vhdx.c')
| -rw-r--r-- | qemu/block/vhdx.c | 1981 |
1 files changed, 0 insertions, 1981 deletions
diff --git a/qemu/block/vhdx.c b/qemu/block/vhdx.c deleted file mode 100644 index 2b7b33240..000000000 --- a/qemu/block/vhdx.c +++ /dev/null @@ -1,1981 +0,0 @@ -/* - * Block driver for Hyper-V VHDX Images - * - * Copyright (c) 2013 Red Hat, Inc., - * - * Authors: - * Jeff Cody <jcody@redhat.com> - * - * This is based on the "VHDX Format Specification v1.00", published 8/25/2012 - * by Microsoft: - * https://www.microsoft.com/en-us/download/details.aspx?id=34750 - * - * This work is licensed under the terms of the GNU LGPL, version 2 or later. - * See the COPYING.LIB file in the top-level directory. - * - */ - -#include "qemu/osdep.h" -#include "qapi/error.h" -#include "qemu-common.h" -#include "block/block_int.h" -#include "sysemu/block-backend.h" -#include "qemu/module.h" -#include "qemu/crc32c.h" -#include "block/vhdx.h" -#include "migration/migration.h" - -#include <uuid/uuid.h> -#include <glib.h> - -/* Options for VHDX creation */ - -#define VHDX_BLOCK_OPT_LOG_SIZE "log_size" -#define VHDX_BLOCK_OPT_BLOCK_SIZE "block_size" -#define VHDX_BLOCK_OPT_ZERO "block_state_zero" - -typedef enum VHDXImageType { - VHDX_TYPE_DYNAMIC = 0, - VHDX_TYPE_FIXED, - VHDX_TYPE_DIFFERENCING, /* Currently unsupported */ -} VHDXImageType; - -/* Several metadata and region table data entries are identified by - * guids in a MS-specific GUID format. */ - - -/* ------- Known Region Table GUIDs ---------------------- */ -static const MSGUID bat_guid = { .data1 = 0x2dc27766, - .data2 = 0xf623, - .data3 = 0x4200, - .data4 = { 0x9d, 0x64, 0x11, 0x5e, - 0x9b, 0xfd, 0x4a, 0x08} }; - -static const MSGUID metadata_guid = { .data1 = 0x8b7ca206, - .data2 = 0x4790, - .data3 = 0x4b9a, - .data4 = { 0xb8, 0xfe, 0x57, 0x5f, - 0x05, 0x0f, 0x88, 0x6e} }; - - - -/* ------- Known Metadata Entry GUIDs ---------------------- */ -static const MSGUID file_param_guid = { .data1 = 0xcaa16737, - .data2 = 0xfa36, - .data3 = 0x4d43, - .data4 = { 0xb3, 0xb6, 0x33, 0xf0, - 0xaa, 0x44, 0xe7, 0x6b} }; - -static const MSGUID virtual_size_guid = { .data1 = 0x2FA54224, - .data2 = 0xcd1b, - .data3 = 0x4876, - .data4 = { 0xb2, 0x11, 0x5d, 0xbe, - 0xd8, 0x3b, 0xf4, 0xb8} }; - -static const MSGUID page83_guid = { .data1 = 0xbeca12ab, - .data2 = 0xb2e6, - .data3 = 0x4523, - .data4 = { 0x93, 0xef, 0xc3, 0x09, - 0xe0, 0x00, 0xc7, 0x46} }; - - -static const MSGUID phys_sector_guid = { .data1 = 0xcda348c7, - .data2 = 0x445d, - .data3 = 0x4471, - .data4 = { 0x9c, 0xc9, 0xe9, 0x88, - 0x52, 0x51, 0xc5, 0x56} }; - -static const MSGUID parent_locator_guid = { .data1 = 0xa8d35f2d, - .data2 = 0xb30b, - .data3 = 0x454d, - .data4 = { 0xab, 0xf7, 0xd3, - 0xd8, 0x48, 0x34, - 0xab, 0x0c} }; - -static const MSGUID logical_sector_guid = { .data1 = 0x8141bf1d, - .data2 = 0xa96f, - .data3 = 0x4709, - .data4 = { 0xba, 0x47, 0xf2, - 0x33, 0xa8, 0xfa, - 0xab, 0x5f} }; - -/* Each parent type must have a valid GUID; this is for parent images - * of type 'VHDX'. If we were to allow e.g. a QCOW2 parent, we would - * need to make up our own QCOW2 GUID type */ -static const MSGUID parent_vhdx_guid __attribute__((unused)) - = { .data1 = 0xb04aefb7, - .data2 = 0xd19e, - .data3 = 0x4a81, - .data4 = { 0xb7, 0x89, 0x25, 0xb8, - 0xe9, 0x44, 0x59, 0x13} }; - - -#define META_FILE_PARAMETER_PRESENT 0x01 -#define META_VIRTUAL_DISK_SIZE_PRESENT 0x02 -#define META_PAGE_83_PRESENT 0x04 -#define META_LOGICAL_SECTOR_SIZE_PRESENT 0x08 -#define META_PHYS_SECTOR_SIZE_PRESENT 0x10 -#define META_PARENT_LOCATOR_PRESENT 0x20 - -#define META_ALL_PRESENT \ - (META_FILE_PARAMETER_PRESENT | META_VIRTUAL_DISK_SIZE_PRESENT | \ - META_PAGE_83_PRESENT | META_LOGICAL_SECTOR_SIZE_PRESENT | \ - META_PHYS_SECTOR_SIZE_PRESENT) - - -typedef struct VHDXSectorInfo { - uint32_t bat_idx; /* BAT entry index */ - uint32_t sectors_avail; /* sectors available in payload block */ - uint32_t bytes_left; /* bytes left in the block after data to r/w */ - uint32_t bytes_avail; /* bytes available in payload block */ - uint64_t file_offset; /* absolute offset in bytes, in file */ - uint64_t block_offset; /* block offset, in bytes */ -} VHDXSectorInfo; - -/* Calculates new checksum. - * - * Zero is substituted during crc calculation for the original crc field - * crc_offset: byte offset in buf of the buffer crc - * buf: buffer pointer - * size: size of buffer (must be > crc_offset+4) - * - * Note: The buffer should have all multi-byte data in little-endian format, - * and the resulting checksum is in little endian format. - */ -uint32_t vhdx_update_checksum(uint8_t *buf, size_t size, int crc_offset) -{ - uint32_t crc; - - assert(buf != NULL); - assert(size > (crc_offset + sizeof(crc))); - - memset(buf + crc_offset, 0, sizeof(crc)); - crc = crc32c(0xffffffff, buf, size); - cpu_to_le32s(&crc); - memcpy(buf + crc_offset, &crc, sizeof(crc)); - - return crc; -} - -uint32_t vhdx_checksum_calc(uint32_t crc, uint8_t *buf, size_t size, - int crc_offset) -{ - uint32_t crc_new; - uint32_t crc_orig; - assert(buf != NULL); - - if (crc_offset > 0) { - memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); - memset(buf + crc_offset, 0, sizeof(crc_orig)); - } - - crc_new = crc32c(crc, buf, size); - if (crc_offset > 0) { - memcpy(buf + crc_offset, &crc_orig, sizeof(crc_orig)); - } - - return crc_new; -} - -/* Validates the checksum of the buffer, with an in-place CRC. - * - * Zero is substituted during crc calculation for the original crc field, - * and the crc field is restored afterwards. But the buffer will be modifed - * during the calculation, so this may not be not suitable for multi-threaded - * use. - * - * crc_offset: byte offset in buf of the buffer crc - * buf: buffer pointer - * size: size of buffer (must be > crc_offset+4) - * - * returns true if checksum is valid, false otherwise - */ -bool vhdx_checksum_is_valid(uint8_t *buf, size_t size, int crc_offset) -{ - uint32_t crc_orig; - uint32_t crc; - - assert(buf != NULL); - assert(size > (crc_offset + 4)); - - memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); - crc_orig = le32_to_cpu(crc_orig); - - crc = vhdx_checksum_calc(0xffffffff, buf, size, crc_offset); - - return crc == crc_orig; -} - - -/* - * This generates a UUID that is compliant with the MS GUIDs used - * in the VHDX spec (and elsewhere). - */ -void vhdx_guid_generate(MSGUID *guid) -{ - uuid_t uuid; - assert(guid != NULL); - - uuid_generate(uuid); - memcpy(guid, uuid, sizeof(MSGUID)); -} - -/* Check for region overlaps inside the VHDX image */ -static int vhdx_region_check(BDRVVHDXState *s, uint64_t start, uint64_t length) -{ - int ret = 0; - uint64_t end; - VHDXRegionEntry *r; - - end = start + length; - QLIST_FOREACH(r, &s->regions, entries) { - if (!((start >= r->end) || (end <= r->start))) { - ret = -EINVAL; - goto exit; - } - } - -exit: - return ret; -} - -/* Register a region for future checks */ -static void vhdx_region_register(BDRVVHDXState *s, - uint64_t start, uint64_t length) -{ - VHDXRegionEntry *r; - - r = g_malloc0(sizeof(*r)); - - r->start = start; - r->end = start + length; - - QLIST_INSERT_HEAD(&s->regions, r, entries); -} - -/* Free all registered regions */ -static void vhdx_region_unregister_all(BDRVVHDXState *s) -{ - VHDXRegionEntry *r, *r_next; - - QLIST_FOREACH_SAFE(r, &s->regions, entries, r_next) { - QLIST_REMOVE(r, entries); - g_free(r); - } -} - -static void vhdx_set_shift_bits(BDRVVHDXState *s) -{ - s->logical_sector_size_bits = ctz32(s->logical_sector_size); - s->sectors_per_block_bits = ctz32(s->sectors_per_block); - s->chunk_ratio_bits = ctz64(s->chunk_ratio); - s->block_size_bits = ctz32(s->block_size); -} - -/* - * Per the MS VHDX Specification, for every VHDX file: - * - The header section is fixed size - 1 MB - * - The header section is always the first "object" - * - The first 64KB of the header is the File Identifier - * - The first uint64 (8 bytes) is the VHDX Signature ("vhdxfile") - * - The following 512 bytes constitute a UTF-16 string identifiying the - * software that created the file, and is optional and diagnostic only. - * - * Therefore, we probe by looking for the vhdxfile signature "vhdxfile" - */ -static int vhdx_probe(const uint8_t *buf, int buf_size, const char *filename) -{ - if (buf_size >= 8 && !memcmp(buf, "vhdxfile", 8)) { - return 100; - } - return 0; -} - -/* - * Writes the header to the specified offset. - * - * This will optionally read in buffer data from disk (otherwise zero-fill), - * and then update the header checksum. Header is converted to proper - * endianness before being written to the specified file offset - */ -static int vhdx_write_header(BlockDriverState *bs_file, VHDXHeader *hdr, - uint64_t offset, bool read) -{ - uint8_t *buffer = NULL; - int ret; - VHDXHeader *header_le; - - assert(bs_file != NULL); - assert(hdr != NULL); - - /* the header checksum is not over just the packed size of VHDXHeader, - * but rather over the entire 'reserved' range for the header, which is - * 4KB (VHDX_HEADER_SIZE). */ - - buffer = qemu_blockalign(bs_file, VHDX_HEADER_SIZE); - if (read) { - /* if true, we can't assume the extra reserved bytes are 0 */ - ret = bdrv_pread(bs_file, offset, buffer, VHDX_HEADER_SIZE); - if (ret < 0) { - goto exit; - } - } else { - memset(buffer, 0, VHDX_HEADER_SIZE); - } - - /* overwrite the actual VHDXHeader portion */ - header_le = (VHDXHeader *)buffer; - memcpy(header_le, hdr, sizeof(VHDXHeader)); - vhdx_header_le_export(hdr, header_le); - vhdx_update_checksum(buffer, VHDX_HEADER_SIZE, - offsetof(VHDXHeader, checksum)); - ret = bdrv_pwrite_sync(bs_file, offset, header_le, sizeof(VHDXHeader)); - -exit: - qemu_vfree(buffer); - return ret; -} - -/* Update the VHDX headers - * - * This follows the VHDX spec procedures for header updates. - * - * - non-current header is updated with largest sequence number - */ -static int vhdx_update_header(BlockDriverState *bs, BDRVVHDXState *s, - bool generate_data_write_guid, MSGUID *log_guid) -{ - int ret = 0; - int hdr_idx = 0; - uint64_t header_offset = VHDX_HEADER1_OFFSET; - - VHDXHeader *active_header; - VHDXHeader *inactive_header; - - /* operate on the non-current header */ - if (s->curr_header == 0) { - hdr_idx = 1; - header_offset = VHDX_HEADER2_OFFSET; - } - - active_header = s->headers[s->curr_header]; - inactive_header = s->headers[hdr_idx]; - - inactive_header->sequence_number = active_header->sequence_number + 1; - - /* a new file guid must be generated before any file write, including - * headers */ - inactive_header->file_write_guid = s->session_guid; - - /* a new data guid only needs to be generated before any guest-visible - * writes (i.e. something observable via virtual disk read) */ - if (generate_data_write_guid) { - vhdx_guid_generate(&inactive_header->data_write_guid); - } - - /* update the log guid if present */ - if (log_guid) { - inactive_header->log_guid = *log_guid; - } - - ret = vhdx_write_header(bs->file->bs, inactive_header, header_offset, true); - if (ret < 0) { - goto exit; - } - s->curr_header = hdr_idx; - -exit: - return ret; -} - -/* - * The VHDX spec calls for header updates to be performed twice, so that both - * the current and non-current header have valid info - */ -int vhdx_update_headers(BlockDriverState *bs, BDRVVHDXState *s, - bool generate_data_write_guid, MSGUID *log_guid) -{ - int ret; - - ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); - if (ret < 0) { - return ret; - } - ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); - return ret; -} - -/* opens the specified header block from the VHDX file header section */ -static void vhdx_parse_header(BlockDriverState *bs, BDRVVHDXState *s, - Error **errp) -{ - int ret; - VHDXHeader *header1; - VHDXHeader *header2; - bool h1_valid = false; - bool h2_valid = false; - uint64_t h1_seq = 0; - uint64_t h2_seq = 0; - uint8_t *buffer; - - /* header1 & header2 are freed in vhdx_close() */ - header1 = qemu_blockalign(bs, sizeof(VHDXHeader)); - header2 = qemu_blockalign(bs, sizeof(VHDXHeader)); - - buffer = qemu_blockalign(bs, VHDX_HEADER_SIZE); - - s->headers[0] = header1; - s->headers[1] = header2; - - /* We have to read the whole VHDX_HEADER_SIZE instead of - * sizeof(VHDXHeader), because the checksum is over the whole - * region */ - ret = bdrv_pread(bs->file->bs, VHDX_HEADER1_OFFSET, buffer, - VHDX_HEADER_SIZE); - if (ret < 0) { - goto fail; - } - /* copy over just the relevant portion that we need */ - memcpy(header1, buffer, sizeof(VHDXHeader)); - - if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4)) { - vhdx_header_le_import(header1); - if (header1->signature == VHDX_HEADER_SIGNATURE && - header1->version == 1) { - h1_seq = header1->sequence_number; - h1_valid = true; - } - } - - ret = bdrv_pread(bs->file->bs, VHDX_HEADER2_OFFSET, buffer, - VHDX_HEADER_SIZE); - if (ret < 0) { - goto fail; - } - /* copy over just the relevant portion that we need */ - memcpy(header2, buffer, sizeof(VHDXHeader)); - - if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4)) { - vhdx_header_le_import(header2); - if (header2->signature == VHDX_HEADER_SIGNATURE && - header2->version == 1) { - h2_seq = header2->sequence_number; - h2_valid = true; - } - } - - /* If there is only 1 valid header (or no valid headers), we - * don't care what the sequence numbers are */ - if (h1_valid && !h2_valid) { - s->curr_header = 0; - } else if (!h1_valid && h2_valid) { - s->curr_header = 1; - } else if (!h1_valid && !h2_valid) { - goto fail; - } else { - /* If both headers are valid, then we choose the active one by the - * highest sequence number. If the sequence numbers are equal, that is - * invalid */ - if (h1_seq > h2_seq) { - s->curr_header = 0; - } else if (h2_seq > h1_seq) { - s->curr_header = 1; - } else { - /* The Microsoft Disk2VHD tool will create 2 identical - * headers, with identical sequence numbers. If the headers are - * identical, don't consider the file corrupt */ - if (!memcmp(header1, header2, sizeof(VHDXHeader))) { - s->curr_header = 0; - } else { - goto fail; - } - } - } - - vhdx_region_register(s, s->headers[s->curr_header]->log_offset, - s->headers[s->curr_header]->log_length); - goto exit; - -fail: - error_setg_errno(errp, -ret, "No valid VHDX header found"); - qemu_vfree(header1); - qemu_vfree(header2); - s->headers[0] = NULL; - s->headers[1] = NULL; -exit: - qemu_vfree(buffer); -} - - -static int vhdx_open_region_tables(BlockDriverState *bs, BDRVVHDXState *s) -{ - int ret = 0; - uint8_t *buffer; - int offset = 0; - VHDXRegionTableEntry rt_entry; - uint32_t i; - bool bat_rt_found = false; - bool metadata_rt_found = false; - - /* We have to read the whole 64KB block, because the crc32 is over the - * whole block */ - buffer = qemu_blockalign(bs, VHDX_HEADER_BLOCK_SIZE); - - ret = bdrv_pread(bs->file->bs, VHDX_REGION_TABLE_OFFSET, buffer, - VHDX_HEADER_BLOCK_SIZE); - if (ret < 0) { - goto fail; - } - memcpy(&s->rt, buffer, sizeof(s->rt)); - offset += sizeof(s->rt); - - if (!vhdx_checksum_is_valid(buffer, VHDX_HEADER_BLOCK_SIZE, 4)) { - ret = -EINVAL; - goto fail; - } - - vhdx_region_header_le_import(&s->rt); - - if (s->rt.signature != VHDX_REGION_SIGNATURE) { - ret = -EINVAL; - goto fail; - } - - - /* Per spec, maximum region table entry count is 2047 */ - if (s->rt.entry_count > 2047) { - ret = -EINVAL; - goto fail; - } - - for (i = 0; i < s->rt.entry_count; i++) { - memcpy(&rt_entry, buffer + offset, sizeof(rt_entry)); - offset += sizeof(rt_entry); - - vhdx_region_entry_le_import(&rt_entry); - - /* check for region overlap between these entries, and any - * other memory regions in the file */ - ret = vhdx_region_check(s, rt_entry.file_offset, rt_entry.length); - if (ret < 0) { - goto fail; - } - - vhdx_region_register(s, rt_entry.file_offset, rt_entry.length); - - /* see if we recognize the entry */ - if (guid_eq(rt_entry.guid, bat_guid)) { - /* must be unique; if we have already found it this is invalid */ - if (bat_rt_found) { - ret = -EINVAL; - goto fail; - } - bat_rt_found = true; - s->bat_rt = rt_entry; - continue; - } - - if (guid_eq(rt_entry.guid, metadata_guid)) { - /* must be unique; if we have already found it this is invalid */ - if (metadata_rt_found) { - ret = -EINVAL; - goto fail; - } - metadata_rt_found = true; - s->metadata_rt = rt_entry; - continue; - } - - if (rt_entry.data_bits & VHDX_REGION_ENTRY_REQUIRED) { - /* cannot read vhdx file - required region table entry that - * we do not understand. per spec, we must fail to open */ - ret = -ENOTSUP; - goto fail; - } - } - - if (!bat_rt_found || !metadata_rt_found) { - ret = -EINVAL; - goto fail; - } - - ret = 0; - -fail: - qemu_vfree(buffer); - return ret; -} - - - -/* Metadata initial parser - * - * This loads all the metadata entry fields. This may cause additional - * fields to be processed (e.g. parent locator, etc..). - * - * There are 5 Metadata items that are always required: - * - File Parameters (block size, has a parent) - * - Virtual Disk Size (size, in bytes, of the virtual drive) - * - Page 83 Data (scsi page 83 guid) - * - Logical Sector Size (logical sector size in bytes, either 512 or - * 4096. We only support 512 currently) - * - Physical Sector Size (512 or 4096) - * - * Also, if the File Parameters indicate this is a differencing file, - * we must also look for the Parent Locator metadata item. - */ -static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s) -{ - int ret = 0; - uint8_t *buffer; - int offset = 0; - uint32_t i = 0; - VHDXMetadataTableEntry md_entry; - - buffer = qemu_blockalign(bs, VHDX_METADATA_TABLE_MAX_SIZE); - - ret = bdrv_pread(bs->file->bs, s->metadata_rt.file_offset, buffer, - VHDX_METADATA_TABLE_MAX_SIZE); - if (ret < 0) { - goto exit; - } - memcpy(&s->metadata_hdr, buffer, sizeof(s->metadata_hdr)); - offset += sizeof(s->metadata_hdr); - - vhdx_metadata_header_le_import(&s->metadata_hdr); - - if (s->metadata_hdr.signature != VHDX_METADATA_SIGNATURE) { - ret = -EINVAL; - goto exit; - } - - s->metadata_entries.present = 0; - - if ((s->metadata_hdr.entry_count * sizeof(md_entry)) > - (VHDX_METADATA_TABLE_MAX_SIZE - offset)) { - ret = -EINVAL; - goto exit; - } - - for (i = 0; i < s->metadata_hdr.entry_count; i++) { - memcpy(&md_entry, buffer + offset, sizeof(md_entry)); - offset += sizeof(md_entry); - - vhdx_metadata_entry_le_import(&md_entry); - - if (guid_eq(md_entry.item_id, file_param_guid)) { - if (s->metadata_entries.present & META_FILE_PARAMETER_PRESENT) { - ret = -EINVAL; - goto exit; - } - s->metadata_entries.file_parameters_entry = md_entry; - s->metadata_entries.present |= META_FILE_PARAMETER_PRESENT; - continue; - } - - if (guid_eq(md_entry.item_id, virtual_size_guid)) { - if (s->metadata_entries.present & META_VIRTUAL_DISK_SIZE_PRESENT) { - ret = -EINVAL; - goto exit; - } - s->metadata_entries.virtual_disk_size_entry = md_entry; - s->metadata_entries.present |= META_VIRTUAL_DISK_SIZE_PRESENT; - continue; - } - - if (guid_eq(md_entry.item_id, page83_guid)) { - if (s->metadata_entries.present & META_PAGE_83_PRESENT) { - ret = -EINVAL; - goto exit; - } - s->metadata_entries.page83_data_entry = md_entry; - s->metadata_entries.present |= META_PAGE_83_PRESENT; - continue; - } - - if (guid_eq(md_entry.item_id, logical_sector_guid)) { - if (s->metadata_entries.present & - META_LOGICAL_SECTOR_SIZE_PRESENT) { - ret = -EINVAL; - goto exit; - } - s->metadata_entries.logical_sector_size_entry = md_entry; - s->metadata_entries.present |= META_LOGICAL_SECTOR_SIZE_PRESENT; - continue; - } - - if (guid_eq(md_entry.item_id, phys_sector_guid)) { - if (s->metadata_entries.present & META_PHYS_SECTOR_SIZE_PRESENT) { - ret = -EINVAL; - goto exit; - } - s->metadata_entries.phys_sector_size_entry = md_entry; - s->metadata_entries.present |= META_PHYS_SECTOR_SIZE_PRESENT; - continue; - } - - if (guid_eq(md_entry.item_id, parent_locator_guid)) { - if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { - ret = -EINVAL; - goto exit; - } - s->metadata_entries.parent_locator_entry = md_entry; - s->metadata_entries.present |= META_PARENT_LOCATOR_PRESENT; - continue; - } - - if (md_entry.data_bits & VHDX_META_FLAGS_IS_REQUIRED) { - /* cannot read vhdx file - required region table entry that - * we do not understand. per spec, we must fail to open */ - ret = -ENOTSUP; - goto exit; - } - } - - if (s->metadata_entries.present != META_ALL_PRESENT) { - ret = -ENOTSUP; - goto exit; - } - - ret = bdrv_pread(bs->file->bs, - s->metadata_entries.file_parameters_entry.offset - + s->metadata_rt.file_offset, - &s->params, - sizeof(s->params)); - - if (ret < 0) { - goto exit; - } - - le32_to_cpus(&s->params.block_size); - le32_to_cpus(&s->params.data_bits); - - - /* We now have the file parameters, so we can tell if this is a - * differencing file (i.e.. has_parent), is dynamic or fixed - * sized (leave_blocks_allocated), and the block size */ - - /* The parent locator required iff the file parameters has_parent set */ - if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { - if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { - /* TODO: parse parent locator fields */ - ret = -ENOTSUP; /* temp, until differencing files are supported */ - goto exit; - } else { - /* if has_parent is set, but there is not parent locator present, - * then that is an invalid combination */ - ret = -EINVAL; - goto exit; - } - } - - /* determine virtual disk size, logical sector size, - * and phys sector size */ - - ret = bdrv_pread(bs->file->bs, - s->metadata_entries.virtual_disk_size_entry.offset - + s->metadata_rt.file_offset, - &s->virtual_disk_size, - sizeof(uint64_t)); - if (ret < 0) { - goto exit; - } - ret = bdrv_pread(bs->file->bs, - s->metadata_entries.logical_sector_size_entry.offset - + s->metadata_rt.file_offset, - &s->logical_sector_size, - sizeof(uint32_t)); - if (ret < 0) { - goto exit; - } - ret = bdrv_pread(bs->file->bs, - s->metadata_entries.phys_sector_size_entry.offset - + s->metadata_rt.file_offset, - &s->physical_sector_size, - sizeof(uint32_t)); - if (ret < 0) { - goto exit; - } - - le64_to_cpus(&s->virtual_disk_size); - le32_to_cpus(&s->logical_sector_size); - le32_to_cpus(&s->physical_sector_size); - - if (s->params.block_size < VHDX_BLOCK_SIZE_MIN || - s->params.block_size > VHDX_BLOCK_SIZE_MAX) { - ret = -EINVAL; - goto exit; - } - - /* only 2 supported sector sizes */ - if (s->logical_sector_size != 512 && s->logical_sector_size != 4096) { - ret = -EINVAL; - goto exit; - } - - /* Both block_size and sector_size are guaranteed powers of 2, below. - Due to range checks above, s->sectors_per_block can never be < 256 */ - s->sectors_per_block = s->params.block_size / s->logical_sector_size; - s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * - (uint64_t)s->logical_sector_size / - (uint64_t)s->params.block_size; - - /* These values are ones we will want to use for division / multiplication - * later on, and they are all guaranteed (per the spec) to be powers of 2, - * so we can take advantage of that for shift operations during - * reads/writes */ - if (s->logical_sector_size & (s->logical_sector_size - 1)) { - ret = -EINVAL; - goto exit; - } - if (s->sectors_per_block & (s->sectors_per_block - 1)) { - ret = -EINVAL; - goto exit; - } - if (s->chunk_ratio & (s->chunk_ratio - 1)) { - ret = -EINVAL; - goto exit; - } - s->block_size = s->params.block_size; - if (s->block_size & (s->block_size - 1)) { - ret = -EINVAL; - goto exit; - } - - vhdx_set_shift_bits(s); - - ret = 0; - -exit: - qemu_vfree(buffer); - return ret; -} - -/* - * Calculate the number of BAT entries, including sector - * bitmap entries. - */ -static void vhdx_calc_bat_entries(BDRVVHDXState *s) -{ - uint32_t data_blocks_cnt, bitmap_blocks_cnt; - - data_blocks_cnt = DIV_ROUND_UP(s->virtual_disk_size, s->block_size); - bitmap_blocks_cnt = DIV_ROUND_UP(data_blocks_cnt, s->chunk_ratio); - - if (s->parent_entries) { - s->bat_entries = bitmap_blocks_cnt * (s->chunk_ratio + 1); - } else { - s->bat_entries = data_blocks_cnt + - ((data_blocks_cnt - 1) >> s->chunk_ratio_bits); - } - -} - -static void vhdx_close(BlockDriverState *bs) -{ - BDRVVHDXState *s = bs->opaque; - qemu_vfree(s->headers[0]); - s->headers[0] = NULL; - qemu_vfree(s->headers[1]); - s->headers[1] = NULL; - qemu_vfree(s->bat); - s->bat = NULL; - qemu_vfree(s->parent_entries); - s->parent_entries = NULL; - migrate_del_blocker(s->migration_blocker); - error_free(s->migration_blocker); - qemu_vfree(s->log.hdr); - s->log.hdr = NULL; - vhdx_region_unregister_all(s); -} - -static int vhdx_open(BlockDriverState *bs, QDict *options, int flags, - Error **errp) -{ - BDRVVHDXState *s = bs->opaque; - int ret = 0; - uint32_t i; - uint64_t signature; - Error *local_err = NULL; - - s->bat = NULL; - s->first_visible_write = true; - - qemu_co_mutex_init(&s->lock); - QLIST_INIT(&s->regions); - - /* validate the file signature */ - ret = bdrv_pread(bs->file->bs, 0, &signature, sizeof(uint64_t)); - if (ret < 0) { - goto fail; - } - if (memcmp(&signature, "vhdxfile", 8)) { - ret = -EINVAL; - goto fail; - } - - /* This is used for any header updates, for the file_write_guid. - * The spec dictates that a new value should be used for the first - * header update */ - vhdx_guid_generate(&s->session_guid); - - vhdx_parse_header(bs, s, &local_err); - if (local_err != NULL) { - error_propagate(errp, local_err); - ret = -EINVAL; - goto fail; - } - - ret = vhdx_parse_log(bs, s, &s->log_replayed_on_open, errp); - if (ret < 0) { - goto fail; - } - - ret = vhdx_open_region_tables(bs, s); - if (ret < 0) { - goto fail; - } - - ret = vhdx_parse_metadata(bs, s); - if (ret < 0) { - goto fail; - } - - s->block_size = s->params.block_size; - - /* the VHDX spec dictates that virtual_disk_size is always a multiple of - * logical_sector_size */ - bs->total_sectors = s->virtual_disk_size >> s->logical_sector_size_bits; - - vhdx_calc_bat_entries(s); - - s->bat_offset = s->bat_rt.file_offset; - - if (s->bat_entries > s->bat_rt.length / sizeof(VHDXBatEntry)) { - /* BAT allocation is not large enough for all entries */ - ret = -EINVAL; - goto fail; - } - - /* s->bat is freed in vhdx_close() */ - s->bat = qemu_try_blockalign(bs->file->bs, s->bat_rt.length); - if (s->bat == NULL) { - ret = -ENOMEM; - goto fail; - } - - ret = bdrv_pread(bs->file->bs, s->bat_offset, s->bat, s->bat_rt.length); - if (ret < 0) { - goto fail; - } - - uint64_t payblocks = s->chunk_ratio; - /* endian convert, and verify populated BAT field file offsets against - * region table and log entries */ - for (i = 0; i < s->bat_entries; i++) { - le64_to_cpus(&s->bat[i]); - if (payblocks--) { - /* payload bat entries */ - if ((s->bat[i] & VHDX_BAT_STATE_BIT_MASK) == - PAYLOAD_BLOCK_FULLY_PRESENT) { - ret = vhdx_region_check(s, s->bat[i] & VHDX_BAT_FILE_OFF_MASK, - s->block_size); - if (ret < 0) { - goto fail; - } - } - } else { - payblocks = s->chunk_ratio; - /* Once differencing files are supported, verify sector bitmap - * blocks here */ - } - } - - if (flags & BDRV_O_RDWR) { - ret = vhdx_update_headers(bs, s, false, NULL); - if (ret < 0) { - goto fail; - } - } - - /* TODO: differencing files */ - - /* Disable migration when VHDX images are used */ - error_setg(&s->migration_blocker, "The vhdx 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: - vhdx_close(bs); - return ret; -} - -static int vhdx_reopen_prepare(BDRVReopenState *state, - BlockReopenQueue *queue, Error **errp) -{ - return 0; -} - - -/* - * Perform sector to block offset translations, to get various - * sector and file offsets into the image. See VHDXSectorInfo - */ -static void vhdx_block_translate(BDRVVHDXState *s, int64_t sector_num, - int nb_sectors, VHDXSectorInfo *sinfo) -{ - uint32_t block_offset; - - sinfo->bat_idx = sector_num >> s->sectors_per_block_bits; - /* effectively a modulo - this gives us the offset into the block - * (in sector sizes) for our sector number */ - block_offset = sector_num - (sinfo->bat_idx << s->sectors_per_block_bits); - /* the chunk ratio gives us the interleaving of the sector - * bitmaps, so we need to advance our page block index by the - * sector bitmaps entry number */ - sinfo->bat_idx += sinfo->bat_idx >> s->chunk_ratio_bits; - - /* the number of sectors we can read/write in this cycle */ - sinfo->sectors_avail = s->sectors_per_block - block_offset; - - sinfo->bytes_left = sinfo->sectors_avail << s->logical_sector_size_bits; - - if (sinfo->sectors_avail > nb_sectors) { - sinfo->sectors_avail = nb_sectors; - } - - sinfo->bytes_avail = sinfo->sectors_avail << s->logical_sector_size_bits; - - sinfo->file_offset = s->bat[sinfo->bat_idx] & VHDX_BAT_FILE_OFF_MASK; - - sinfo->block_offset = block_offset << s->logical_sector_size_bits; - - /* The file offset must be past the header section, so must be > 0 */ - if (sinfo->file_offset == 0) { - return; - } - - /* block offset is the offset in vhdx logical sectors, in - * the payload data block. Convert that to a byte offset - * in the block, and add in the payload data block offset - * in the file, in bytes, to get the final read address */ - - sinfo->file_offset += sinfo->block_offset; -} - - -static int vhdx_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) -{ - BDRVVHDXState *s = bs->opaque; - - bdi->cluster_size = s->block_size; - - bdi->unallocated_blocks_are_zero = - (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) == 0; - - return 0; -} - - -static coroutine_fn int vhdx_co_readv(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, QEMUIOVector *qiov) -{ - BDRVVHDXState *s = bs->opaque; - int ret = 0; - VHDXSectorInfo sinfo; - uint64_t bytes_done = 0; - QEMUIOVector hd_qiov; - - qemu_iovec_init(&hd_qiov, qiov->niov); - - qemu_co_mutex_lock(&s->lock); - - while (nb_sectors > 0) { - /* We are a differencing file, so we need to inspect the sector bitmap - * to see if we have the data or not */ - if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { - /* not supported yet */ - ret = -ENOTSUP; - goto exit; - } else { - vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); - - qemu_iovec_reset(&hd_qiov); - qemu_iovec_concat(&hd_qiov, qiov, bytes_done, sinfo.bytes_avail); - - /* check the payload block state */ - switch (s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK) { - case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ - case PAYLOAD_BLOCK_UNDEFINED: - case PAYLOAD_BLOCK_UNMAPPED: - case PAYLOAD_BLOCK_UNMAPPED_v095: - case PAYLOAD_BLOCK_ZERO: - /* return zero */ - qemu_iovec_memset(&hd_qiov, 0, 0, sinfo.bytes_avail); - break; - case PAYLOAD_BLOCK_FULLY_PRESENT: - qemu_co_mutex_unlock(&s->lock); - ret = bdrv_co_readv(bs->file->bs, - sinfo.file_offset >> BDRV_SECTOR_BITS, - sinfo.sectors_avail, &hd_qiov); - qemu_co_mutex_lock(&s->lock); - if (ret < 0) { - goto exit; - } - break; - case PAYLOAD_BLOCK_PARTIALLY_PRESENT: - /* we don't yet support difference files, fall through - * to error */ - default: - ret = -EIO; - goto exit; - break; - } - nb_sectors -= sinfo.sectors_avail; - sector_num += sinfo.sectors_avail; - bytes_done += sinfo.bytes_avail; - } - } - ret = 0; -exit: - qemu_co_mutex_unlock(&s->lock); - qemu_iovec_destroy(&hd_qiov); - return ret; -} - -/* - * Allocate a new payload block at the end of the file. - * - * Allocation will happen at 1MB alignment inside the file - * - * Returns the file offset start of the new payload block - */ -static int vhdx_allocate_block(BlockDriverState *bs, BDRVVHDXState *s, - uint64_t *new_offset) -{ - *new_offset = bdrv_getlength(bs->file->bs); - - /* per the spec, the address for a block is in units of 1MB */ - *new_offset = ROUND_UP(*new_offset, 1024 * 1024); - - return bdrv_truncate(bs->file->bs, *new_offset + s->block_size); -} - -/* - * Update the BAT table entry with the new file offset, and the new entry - * state */ -static void vhdx_update_bat_table_entry(BlockDriverState *bs, BDRVVHDXState *s, - VHDXSectorInfo *sinfo, - uint64_t *bat_entry_le, - uint64_t *bat_offset, int state) -{ - /* The BAT entry is a uint64, with 44 bits for the file offset in units of - * 1MB, and 3 bits for the block state. */ - if ((state == PAYLOAD_BLOCK_ZERO) || - (state == PAYLOAD_BLOCK_UNDEFINED) || - (state == PAYLOAD_BLOCK_NOT_PRESENT) || - (state == PAYLOAD_BLOCK_UNMAPPED)) { - s->bat[sinfo->bat_idx] = 0; /* For PAYLOAD_BLOCK_ZERO, the - FileOffsetMB field is denoted as - 'reserved' in the v1.0 spec. If it is - non-zero, MS Hyper-V will fail to read - the disk image */ - } else { - s->bat[sinfo->bat_idx] = sinfo->file_offset; - } - - s->bat[sinfo->bat_idx] |= state & VHDX_BAT_STATE_BIT_MASK; - - *bat_entry_le = cpu_to_le64(s->bat[sinfo->bat_idx]); - *bat_offset = s->bat_offset + sinfo->bat_idx * sizeof(VHDXBatEntry); - -} - -/* Per the spec, on the first write of guest-visible data to the file the - * data write guid must be updated in the header */ -int vhdx_user_visible_write(BlockDriverState *bs, BDRVVHDXState *s) -{ - int ret = 0; - if (s->first_visible_write) { - s->first_visible_write = false; - ret = vhdx_update_headers(bs, s, true, NULL); - } - return ret; -} - -static coroutine_fn int vhdx_co_writev(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, QEMUIOVector *qiov) -{ - int ret = -ENOTSUP; - BDRVVHDXState *s = bs->opaque; - VHDXSectorInfo sinfo; - uint64_t bytes_done = 0; - uint64_t bat_entry = 0; - uint64_t bat_entry_offset = 0; - QEMUIOVector hd_qiov; - struct iovec iov1 = { 0 }; - struct iovec iov2 = { 0 }; - int sectors_to_write; - int bat_state; - uint64_t bat_prior_offset = 0; - bool bat_update = false; - - qemu_iovec_init(&hd_qiov, qiov->niov); - - qemu_co_mutex_lock(&s->lock); - - ret = vhdx_user_visible_write(bs, s); - if (ret < 0) { - goto exit; - } - - while (nb_sectors > 0) { - bool use_zero_buffers = false; - bat_update = false; - if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { - /* not supported yet */ - ret = -ENOTSUP; - goto exit; - } else { - vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); - sectors_to_write = sinfo.sectors_avail; - - qemu_iovec_reset(&hd_qiov); - /* check the payload block state */ - bat_state = s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK; - switch (bat_state) { - case PAYLOAD_BLOCK_ZERO: - /* in this case, we need to preserve zero writes for - * data that is not part of this write, so we must pad - * the rest of the buffer to zeroes */ - - /* if we are on a posix system with ftruncate() that extends - * a file, then it is zero-filled for us. On Win32, the raw - * layer uses SetFilePointer and SetFileEnd, which does not - * zero fill AFAIK */ - - /* Queue another write of zero buffers if the underlying file - * does not zero-fill on file extension */ - - if (bdrv_has_zero_init(bs->file->bs) == 0) { - use_zero_buffers = true; - - /* zero fill the front, if any */ - if (sinfo.block_offset) { - iov1.iov_len = sinfo.block_offset; - iov1.iov_base = qemu_blockalign(bs, iov1.iov_len); - memset(iov1.iov_base, 0, iov1.iov_len); - qemu_iovec_concat_iov(&hd_qiov, &iov1, 1, 0, - iov1.iov_len); - sectors_to_write += iov1.iov_len >> BDRV_SECTOR_BITS; - } - - /* our actual data */ - qemu_iovec_concat(&hd_qiov, qiov, bytes_done, - sinfo.bytes_avail); - - /* zero fill the back, if any */ - if ((sinfo.bytes_avail - sinfo.block_offset) < - s->block_size) { - iov2.iov_len = s->block_size - - (sinfo.bytes_avail + sinfo.block_offset); - iov2.iov_base = qemu_blockalign(bs, iov2.iov_len); - memset(iov2.iov_base, 0, iov2.iov_len); - qemu_iovec_concat_iov(&hd_qiov, &iov2, 1, 0, - iov2.iov_len); - sectors_to_write += iov2.iov_len >> BDRV_SECTOR_BITS; - } - } - /* fall through */ - case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ - case PAYLOAD_BLOCK_UNMAPPED: - case PAYLOAD_BLOCK_UNMAPPED_v095: - case PAYLOAD_BLOCK_UNDEFINED: - bat_prior_offset = sinfo.file_offset; - ret = vhdx_allocate_block(bs, s, &sinfo.file_offset); - if (ret < 0) { - goto exit; - } - /* once we support differencing files, this may also be - * partially present */ - /* update block state to the newly specified state */ - vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, - &bat_entry_offset, - PAYLOAD_BLOCK_FULLY_PRESENT); - bat_update = true; - /* since we just allocated a block, file_offset is the - * beginning of the payload block. It needs to be the - * write address, which includes the offset into the block */ - if (!use_zero_buffers) { - sinfo.file_offset += sinfo.block_offset; - } - /* fall through */ - case PAYLOAD_BLOCK_FULLY_PRESENT: - /* if the file offset address is in the header zone, - * there is a problem */ - if (sinfo.file_offset < (1024 * 1024)) { - ret = -EFAULT; - goto error_bat_restore; - } - - if (!use_zero_buffers) { - qemu_iovec_concat(&hd_qiov, qiov, bytes_done, - sinfo.bytes_avail); - } - /* block exists, so we can just overwrite it */ - qemu_co_mutex_unlock(&s->lock); - ret = bdrv_co_writev(bs->file->bs, - sinfo.file_offset >> BDRV_SECTOR_BITS, - sectors_to_write, &hd_qiov); - qemu_co_mutex_lock(&s->lock); - if (ret < 0) { - goto error_bat_restore; - } - break; - case PAYLOAD_BLOCK_PARTIALLY_PRESENT: - /* we don't yet support difference files, fall through - * to error */ - default: - ret = -EIO; - goto exit; - break; - } - - if (bat_update) { - /* this will update the BAT entry into the log journal, and - * then flush the log journal out to disk */ - ret = vhdx_log_write_and_flush(bs, s, &bat_entry, - sizeof(VHDXBatEntry), - bat_entry_offset); - if (ret < 0) { - goto exit; - } - } - - nb_sectors -= sinfo.sectors_avail; - sector_num += sinfo.sectors_avail; - bytes_done += sinfo.bytes_avail; - - } - } - - goto exit; - -error_bat_restore: - if (bat_update) { - /* keep metadata in sync, and restore the bat entry state - * if error. */ - sinfo.file_offset = bat_prior_offset; - vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, - &bat_entry_offset, bat_state); - } -exit: - qemu_vfree(iov1.iov_base); - qemu_vfree(iov2.iov_base); - qemu_co_mutex_unlock(&s->lock); - qemu_iovec_destroy(&hd_qiov); - return ret; -} - - - -/* - * Create VHDX Headers - * - * There are 2 headers, and the highest sequence number will represent - * the active header - */ -static int vhdx_create_new_headers(BlockDriverState *bs, uint64_t image_size, - uint32_t log_size) -{ - int ret = 0; - VHDXHeader *hdr = NULL; - - hdr = g_new0(VHDXHeader, 1); - - hdr->signature = VHDX_HEADER_SIGNATURE; - hdr->sequence_number = g_random_int(); - hdr->log_version = 0; - hdr->version = 1; - hdr->log_length = log_size; - hdr->log_offset = VHDX_HEADER_SECTION_END; - vhdx_guid_generate(&hdr->file_write_guid); - vhdx_guid_generate(&hdr->data_write_guid); - - ret = vhdx_write_header(bs, hdr, VHDX_HEADER1_OFFSET, false); - if (ret < 0) { - goto exit; - } - hdr->sequence_number++; - ret = vhdx_write_header(bs, hdr, VHDX_HEADER2_OFFSET, false); - if (ret < 0) { - goto exit; - } - -exit: - g_free(hdr); - return ret; -} - -#define VHDX_METADATA_ENTRY_BUFFER_SIZE \ - (sizeof(VHDXFileParameters) +\ - sizeof(VHDXVirtualDiskSize) +\ - sizeof(VHDXPage83Data) +\ - sizeof(VHDXVirtualDiskLogicalSectorSize) +\ - sizeof(VHDXVirtualDiskPhysicalSectorSize)) - -/* - * Create the Metadata entries. - * - * For more details on the entries, see section 3.5 (pg 29) in the - * VHDX 1.00 specification. - * - * We support 5 metadata entries (all required by spec): - * File Parameters, - * Virtual Disk Size, - * Page 83 Data, - * Logical Sector Size, - * Physical Sector Size - * - * The first 64KB of the Metadata section is reserved for the metadata - * header and entries; beyond that, the metadata items themselves reside. - */ -static int vhdx_create_new_metadata(BlockDriverState *bs, - uint64_t image_size, - uint32_t block_size, - uint32_t sector_size, - uint64_t metadata_offset, - VHDXImageType type) -{ - int ret = 0; - uint32_t offset = 0; - void *buffer = NULL; - void *entry_buffer; - VHDXMetadataTableHeader *md_table; - VHDXMetadataTableEntry *md_table_entry; - - /* Metadata entries */ - VHDXFileParameters *mt_file_params; - VHDXVirtualDiskSize *mt_virtual_size; - VHDXPage83Data *mt_page83; - VHDXVirtualDiskLogicalSectorSize *mt_log_sector_size; - VHDXVirtualDiskPhysicalSectorSize *mt_phys_sector_size; - - entry_buffer = g_malloc0(VHDX_METADATA_ENTRY_BUFFER_SIZE); - - mt_file_params = entry_buffer; - offset += sizeof(VHDXFileParameters); - mt_virtual_size = entry_buffer + offset; - offset += sizeof(VHDXVirtualDiskSize); - mt_page83 = entry_buffer + offset; - offset += sizeof(VHDXPage83Data); - mt_log_sector_size = entry_buffer + offset; - offset += sizeof(VHDXVirtualDiskLogicalSectorSize); - mt_phys_sector_size = entry_buffer + offset; - - mt_file_params->block_size = cpu_to_le32(block_size); - if (type == VHDX_TYPE_FIXED) { - mt_file_params->data_bits |= VHDX_PARAMS_LEAVE_BLOCKS_ALLOCED; - cpu_to_le32s(&mt_file_params->data_bits); - } - - vhdx_guid_generate(&mt_page83->page_83_data); - cpu_to_leguids(&mt_page83->page_83_data); - mt_virtual_size->virtual_disk_size = cpu_to_le64(image_size); - mt_log_sector_size->logical_sector_size = cpu_to_le32(sector_size); - mt_phys_sector_size->physical_sector_size = cpu_to_le32(sector_size); - - buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); - md_table = buffer; - - md_table->signature = VHDX_METADATA_SIGNATURE; - md_table->entry_count = 5; - vhdx_metadata_header_le_export(md_table); - - - /* This will reference beyond the reserved table portion */ - offset = 64 * KiB; - - md_table_entry = buffer + sizeof(VHDXMetadataTableHeader); - - md_table_entry[0].item_id = file_param_guid; - md_table_entry[0].offset = offset; - md_table_entry[0].length = sizeof(VHDXFileParameters); - md_table_entry[0].data_bits |= VHDX_META_FLAGS_IS_REQUIRED; - offset += md_table_entry[0].length; - vhdx_metadata_entry_le_export(&md_table_entry[0]); - - md_table_entry[1].item_id = virtual_size_guid; - md_table_entry[1].offset = offset; - md_table_entry[1].length = sizeof(VHDXVirtualDiskSize); - md_table_entry[1].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | - VHDX_META_FLAGS_IS_VIRTUAL_DISK; - offset += md_table_entry[1].length; - vhdx_metadata_entry_le_export(&md_table_entry[1]); - - md_table_entry[2].item_id = page83_guid; - md_table_entry[2].offset = offset; - md_table_entry[2].length = sizeof(VHDXPage83Data); - md_table_entry[2].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | - VHDX_META_FLAGS_IS_VIRTUAL_DISK; - offset += md_table_entry[2].length; - vhdx_metadata_entry_le_export(&md_table_entry[2]); - - md_table_entry[3].item_id = logical_sector_guid; - md_table_entry[3].offset = offset; - md_table_entry[3].length = sizeof(VHDXVirtualDiskLogicalSectorSize); - md_table_entry[3].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | - VHDX_META_FLAGS_IS_VIRTUAL_DISK; - offset += md_table_entry[3].length; - vhdx_metadata_entry_le_export(&md_table_entry[3]); - - md_table_entry[4].item_id = phys_sector_guid; - md_table_entry[4].offset = offset; - md_table_entry[4].length = sizeof(VHDXVirtualDiskPhysicalSectorSize); - md_table_entry[4].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | - VHDX_META_FLAGS_IS_VIRTUAL_DISK; - vhdx_metadata_entry_le_export(&md_table_entry[4]); - - ret = bdrv_pwrite(bs, metadata_offset, buffer, VHDX_HEADER_BLOCK_SIZE); - if (ret < 0) { - goto exit; - } - - ret = bdrv_pwrite(bs, metadata_offset + (64 * KiB), entry_buffer, - VHDX_METADATA_ENTRY_BUFFER_SIZE); - if (ret < 0) { - goto exit; - } - - -exit: - g_free(buffer); - g_free(entry_buffer); - return ret; -} - -/* This create the actual BAT itself. We currently only support - * 'Dynamic' and 'Fixed' image types. - * - * Dynamic images: default state of the BAT is all zeroes. - * - * Fixed images: default state of the BAT is fully populated, with - * file offsets and state PAYLOAD_BLOCK_FULLY_PRESENT. - */ -static int vhdx_create_bat(BlockDriverState *bs, BDRVVHDXState *s, - uint64_t image_size, VHDXImageType type, - bool use_zero_blocks, uint64_t file_offset, - uint32_t length) -{ - int ret = 0; - uint64_t data_file_offset; - uint64_t total_sectors = 0; - uint64_t sector_num = 0; - uint64_t unused; - int block_state; - VHDXSectorInfo sinfo; - - assert(s->bat == NULL); - - /* this gives a data start after BAT/bitmap entries, and well - * past any metadata entries (with a 4 MB buffer for future - * expansion */ - data_file_offset = file_offset + length + 5 * MiB; - total_sectors = image_size >> s->logical_sector_size_bits; - - if (type == VHDX_TYPE_DYNAMIC) { - /* All zeroes, so we can just extend the file - the end of the BAT - * is the furthest thing we have written yet */ - ret = bdrv_truncate(bs, data_file_offset); - if (ret < 0) { - goto exit; - } - } else if (type == VHDX_TYPE_FIXED) { - ret = bdrv_truncate(bs, data_file_offset + image_size); - if (ret < 0) { - goto exit; - } - } else { - ret = -ENOTSUP; - goto exit; - } - - if (type == VHDX_TYPE_FIXED || - use_zero_blocks || - bdrv_has_zero_init(bs) == 0) { - /* for a fixed file, the default BAT entry is not zero */ - s->bat = g_try_malloc0(length); - if (length && s->bat == NULL) { - ret = -ENOMEM; - goto exit; - } - block_state = type == VHDX_TYPE_FIXED ? PAYLOAD_BLOCK_FULLY_PRESENT : - PAYLOAD_BLOCK_NOT_PRESENT; - block_state = use_zero_blocks ? PAYLOAD_BLOCK_ZERO : block_state; - /* fill the BAT by emulating sector writes of sectors_per_block size */ - while (sector_num < total_sectors) { - vhdx_block_translate(s, sector_num, s->sectors_per_block, &sinfo); - sinfo.file_offset = data_file_offset + - (sector_num << s->logical_sector_size_bits); - sinfo.file_offset = ROUND_UP(sinfo.file_offset, MiB); - vhdx_update_bat_table_entry(bs, s, &sinfo, &unused, &unused, - block_state); - cpu_to_le64s(&s->bat[sinfo.bat_idx]); - sector_num += s->sectors_per_block; - } - ret = bdrv_pwrite(bs, file_offset, s->bat, length); - if (ret < 0) { - goto exit; - } - } - - - -exit: - g_free(s->bat); - return ret; -} - -/* Creates the region table header, and region table entries. - * There are 2 supported region table entries: BAT, and Metadata/ - * - * As the calculations for the BAT region table are also needed - * to create the BAT itself, we will also cause the BAT to be - * created. - */ -static int vhdx_create_new_region_table(BlockDriverState *bs, - uint64_t image_size, - uint32_t block_size, - uint32_t sector_size, - uint32_t log_size, - bool use_zero_blocks, - VHDXImageType type, - uint64_t *metadata_offset) -{ - int ret = 0; - uint32_t offset = 0; - void *buffer = NULL; - uint64_t bat_file_offset; - uint32_t bat_length; - BDRVVHDXState *s = NULL; - VHDXRegionTableHeader *region_table; - VHDXRegionTableEntry *rt_bat; - VHDXRegionTableEntry *rt_metadata; - - assert(metadata_offset != NULL); - - /* Populate enough of the BDRVVHDXState to be able to use the - * pre-existing BAT calculation, translation, and update functions */ - s = g_new0(BDRVVHDXState, 1); - - s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * - (uint64_t) sector_size / (uint64_t) block_size; - - s->sectors_per_block = block_size / sector_size; - s->virtual_disk_size = image_size; - s->block_size = block_size; - s->logical_sector_size = sector_size; - - vhdx_set_shift_bits(s); - - vhdx_calc_bat_entries(s); - - /* At this point the VHDX state is populated enough for creation */ - - /* a single buffer is used so we can calculate the checksum over the - * entire 64KB block */ - buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); - region_table = buffer; - offset += sizeof(VHDXRegionTableHeader); - rt_bat = buffer + offset; - offset += sizeof(VHDXRegionTableEntry); - rt_metadata = buffer + offset; - - region_table->signature = VHDX_REGION_SIGNATURE; - region_table->entry_count = 2; /* BAT and Metadata */ - - rt_bat->guid = bat_guid; - rt_bat->length = ROUND_UP(s->bat_entries * sizeof(VHDXBatEntry), MiB); - rt_bat->file_offset = ROUND_UP(VHDX_HEADER_SECTION_END + log_size, MiB); - s->bat_offset = rt_bat->file_offset; - - rt_metadata->guid = metadata_guid; - rt_metadata->file_offset = ROUND_UP(rt_bat->file_offset + rt_bat->length, - MiB); - rt_metadata->length = 1 * MiB; /* min size, and more than enough */ - *metadata_offset = rt_metadata->file_offset; - - bat_file_offset = rt_bat->file_offset; - bat_length = rt_bat->length; - - vhdx_region_header_le_export(region_table); - vhdx_region_entry_le_export(rt_bat); - vhdx_region_entry_le_export(rt_metadata); - - vhdx_update_checksum(buffer, VHDX_HEADER_BLOCK_SIZE, - offsetof(VHDXRegionTableHeader, checksum)); - - - /* The region table gives us the data we need to create the BAT, - * so do that now */ - ret = vhdx_create_bat(bs, s, image_size, type, use_zero_blocks, - bat_file_offset, bat_length); - if (ret < 0) { - goto exit; - } - - /* Now write out the region headers to disk */ - ret = bdrv_pwrite(bs, VHDX_REGION_TABLE_OFFSET, buffer, - VHDX_HEADER_BLOCK_SIZE); - if (ret < 0) { - goto exit; - } - - ret = bdrv_pwrite(bs, VHDX_REGION_TABLE2_OFFSET, buffer, - VHDX_HEADER_BLOCK_SIZE); - if (ret < 0) { - goto exit; - } - -exit: - g_free(s); - g_free(buffer); - return ret; -} - -/* We need to create the following elements: - * - * .-----------------------------------------------------------------. - * | (A) | (B) | (C) | (D) | (E) | - * | File ID | Header1 | Header 2 | Region Tbl 1 | Region Tbl 2 | - * | | | | | | - * .-----------------------------------------------------------------. - * 0 64KB 128KB 192KB 256KB 320KB - * - * - * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. - * | (F) | (G) | (H) | | - * | Journal Log | BAT / Bitmap | Metadata | .... data ...... | - * | | | | | - * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. - * 1MB - */ -static int vhdx_create(const char *filename, QemuOpts *opts, Error **errp) -{ - int ret = 0; - uint64_t image_size = (uint64_t) 2 * GiB; - uint32_t log_size = 1 * MiB; - uint32_t block_size = 0; - uint64_t signature; - uint64_t metadata_offset; - bool use_zero_blocks = false; - - gunichar2 *creator = NULL; - glong creator_items; - BlockBackend *blk; - char *type = NULL; - VHDXImageType image_type; - Error *local_err = NULL; - - image_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), - BDRV_SECTOR_SIZE); - log_size = qemu_opt_get_size_del(opts, VHDX_BLOCK_OPT_LOG_SIZE, 0); - block_size = qemu_opt_get_size_del(opts, VHDX_BLOCK_OPT_BLOCK_SIZE, 0); - type = qemu_opt_get_del(opts, BLOCK_OPT_SUBFMT); - use_zero_blocks = qemu_opt_get_bool_del(opts, VHDX_BLOCK_OPT_ZERO, true); - - if (image_size > VHDX_MAX_IMAGE_SIZE) { - error_setg_errno(errp, EINVAL, "Image size too large; max of 64TB"); - ret = -EINVAL; - goto exit; - } - - if (type == NULL) { - type = g_strdup("dynamic"); - } - - if (!strcmp(type, "dynamic")) { - image_type = VHDX_TYPE_DYNAMIC; - } else if (!strcmp(type, "fixed")) { - image_type = VHDX_TYPE_FIXED; - } else if (!strcmp(type, "differencing")) { - error_setg_errno(errp, ENOTSUP, - "Differencing files not yet supported"); - ret = -ENOTSUP; - goto exit; - } else { - ret = -EINVAL; - goto exit; - } - - /* These are pretty arbitrary, and mainly designed to keep the BAT - * size reasonable to load into RAM */ - if (block_size == 0) { - if (image_size > 32 * TiB) { - block_size = 64 * MiB; - } else if (image_size > (uint64_t) 100 * GiB) { - block_size = 32 * MiB; - } else if (image_size > 1 * GiB) { - block_size = 16 * MiB; - } else { - block_size = 8 * MiB; - } - } - - - /* make the log size close to what was specified, but must be - * min 1MB, and multiple of 1MB */ - log_size = ROUND_UP(log_size, MiB); - - block_size = ROUND_UP(block_size, MiB); - block_size = block_size > VHDX_BLOCK_SIZE_MAX ? VHDX_BLOCK_SIZE_MAX : - block_size; - - 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); - - /* Create (A) */ - - /* The creator field is optional, but may be useful for - * debugging / diagnostics */ - creator = g_utf8_to_utf16("QEMU v" QEMU_VERSION, -1, NULL, - &creator_items, NULL); - signature = cpu_to_le64(VHDX_FILE_SIGNATURE); - ret = blk_pwrite(blk, VHDX_FILE_ID_OFFSET, &signature, sizeof(signature)); - if (ret < 0) { - goto delete_and_exit; - } - if (creator) { - ret = blk_pwrite(blk, VHDX_FILE_ID_OFFSET + sizeof(signature), - creator, creator_items * sizeof(gunichar2)); - if (ret < 0) { - goto delete_and_exit; - } - } - - - /* Creates (B),(C) */ - ret = vhdx_create_new_headers(blk_bs(blk), image_size, log_size); - if (ret < 0) { - goto delete_and_exit; - } - - /* Creates (D),(E),(G) explicitly. (F) created as by-product */ - ret = vhdx_create_new_region_table(blk_bs(blk), image_size, block_size, 512, - log_size, use_zero_blocks, image_type, - &metadata_offset); - if (ret < 0) { - goto delete_and_exit; - } - - /* Creates (H) */ - ret = vhdx_create_new_metadata(blk_bs(blk), image_size, block_size, 512, - metadata_offset, image_type); - if (ret < 0) { - goto delete_and_exit; - } - - -delete_and_exit: - blk_unref(blk); -exit: - g_free(type); - g_free(creator); - return ret; -} - -/* If opened r/w, the VHDX driver will automatically replay the log, - * if one is present, inside the vhdx_open() call. - * - * If qemu-img check -r all is called, the image is automatically opened - * r/w and any log has already been replayed, so there is nothing (currently) - * for us to do here - */ -static int vhdx_check(BlockDriverState *bs, BdrvCheckResult *result, - BdrvCheckMode fix) -{ - BDRVVHDXState *s = bs->opaque; - - if (s->log_replayed_on_open) { - result->corruptions_fixed++; - } - return 0; -} - -static QemuOptsList vhdx_create_opts = { - .name = "vhdx-create-opts", - .head = QTAILQ_HEAD_INITIALIZER(vhdx_create_opts.head), - .desc = { - { - .name = BLOCK_OPT_SIZE, - .type = QEMU_OPT_SIZE, - .help = "Virtual disk size; max of 64TB." - }, - { - .name = VHDX_BLOCK_OPT_LOG_SIZE, - .type = QEMU_OPT_SIZE, - .def_value_str = stringify(DEFAULT_LOG_SIZE), - .help = "Log size; min 1MB." - }, - { - .name = VHDX_BLOCK_OPT_BLOCK_SIZE, - .type = QEMU_OPT_SIZE, - .def_value_str = stringify(0), - .help = "Block Size; min 1MB, max 256MB. " \ - "0 means auto-calculate based on image size." - }, - { - .name = BLOCK_OPT_SUBFMT, - .type = QEMU_OPT_STRING, - .help = "VHDX format type, can be either 'dynamic' or 'fixed'. "\ - "Default is 'dynamic'." - }, - { - .name = VHDX_BLOCK_OPT_ZERO, - .type = QEMU_OPT_BOOL, - .help = "Force use of payload blocks of type 'ZERO'. "\ - "Non-standard, but default. Do not set to 'off' when "\ - "using 'qemu-img convert' with subformat=dynamic." - }, - { NULL } - } -}; - -static BlockDriver bdrv_vhdx = { - .format_name = "vhdx", - .instance_size = sizeof(BDRVVHDXState), - .bdrv_probe = vhdx_probe, - .bdrv_open = vhdx_open, - .bdrv_close = vhdx_close, - .bdrv_reopen_prepare = vhdx_reopen_prepare, - .bdrv_co_readv = vhdx_co_readv, - .bdrv_co_writev = vhdx_co_writev, - .bdrv_create = vhdx_create, - .bdrv_get_info = vhdx_get_info, - .bdrv_check = vhdx_check, - .bdrv_has_zero_init = bdrv_has_zero_init_1, - - .create_opts = &vhdx_create_opts, -}; - -static void bdrv_vhdx_init(void) -{ - bdrv_register(&bdrv_vhdx); -} - -block_init(bdrv_vhdx_init); |