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2262 lines
74 KiB
C
2262 lines
74 KiB
C
/*
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* Block driver for Hyper-V VHDX Images
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*
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* Copyright (c) 2013 Red Hat, Inc.,
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*
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* Authors:
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* Jeff Cody <jcody@redhat.com>
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*
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* This is based on the "VHDX Format Specification v1.00", published 8/25/2012
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* by Microsoft:
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* https://www.microsoft.com/en-us/download/details.aspx?id=34750
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*
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* This work is licensed under the terms of the GNU LGPL, version 2 or later.
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* See the COPYING.LIB file in the top-level directory.
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*
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*/
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#include "qemu/osdep.h"
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#include "qapi/error.h"
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#include "block/block_int.h"
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#include "block/qdict.h"
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#include "sysemu/block-backend.h"
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#include "qemu/module.h"
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#include "qemu/option.h"
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#include "qemu/crc32c.h"
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#include "qemu/bswap.h"
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#include "qemu/error-report.h"
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#include "qemu/memalign.h"
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#include "vhdx.h"
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#include "migration/blocker.h"
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#include "qemu/uuid.h"
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#include "qapi/qmp/qdict.h"
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#include "qapi/qobject-input-visitor.h"
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#include "qapi/qapi-visit-block-core.h"
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/* Options for VHDX creation */
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#define VHDX_BLOCK_OPT_LOG_SIZE "log_size"
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#define VHDX_BLOCK_OPT_BLOCK_SIZE "block_size"
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#define VHDX_BLOCK_OPT_ZERO "block_state_zero"
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typedef enum VHDXImageType {
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VHDX_TYPE_DYNAMIC = 0,
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VHDX_TYPE_FIXED,
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VHDX_TYPE_DIFFERENCING, /* Currently unsupported */
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} VHDXImageType;
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static QemuOptsList vhdx_create_opts;
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/* Several metadata and region table data entries are identified by
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* guids in a MS-specific GUID format. */
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/* ------- Known Region Table GUIDs ---------------------- */
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static const MSGUID bat_guid = { .data1 = 0x2dc27766,
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.data2 = 0xf623,
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.data3 = 0x4200,
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.data4 = { 0x9d, 0x64, 0x11, 0x5e,
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0x9b, 0xfd, 0x4a, 0x08} };
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static const MSGUID metadata_guid = { .data1 = 0x8b7ca206,
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.data2 = 0x4790,
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.data3 = 0x4b9a,
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.data4 = { 0xb8, 0xfe, 0x57, 0x5f,
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0x05, 0x0f, 0x88, 0x6e} };
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/* ------- Known Metadata Entry GUIDs ---------------------- */
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static const MSGUID file_param_guid = { .data1 = 0xcaa16737,
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.data2 = 0xfa36,
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.data3 = 0x4d43,
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.data4 = { 0xb3, 0xb6, 0x33, 0xf0,
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0xaa, 0x44, 0xe7, 0x6b} };
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static const MSGUID virtual_size_guid = { .data1 = 0x2FA54224,
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.data2 = 0xcd1b,
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.data3 = 0x4876,
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.data4 = { 0xb2, 0x11, 0x5d, 0xbe,
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0xd8, 0x3b, 0xf4, 0xb8} };
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static const MSGUID page83_guid = { .data1 = 0xbeca12ab,
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.data2 = 0xb2e6,
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.data3 = 0x4523,
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.data4 = { 0x93, 0xef, 0xc3, 0x09,
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0xe0, 0x00, 0xc7, 0x46} };
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static const MSGUID phys_sector_guid = { .data1 = 0xcda348c7,
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.data2 = 0x445d,
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.data3 = 0x4471,
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.data4 = { 0x9c, 0xc9, 0xe9, 0x88,
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0x52, 0x51, 0xc5, 0x56} };
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static const MSGUID parent_locator_guid = { .data1 = 0xa8d35f2d,
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.data2 = 0xb30b,
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.data3 = 0x454d,
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.data4 = { 0xab, 0xf7, 0xd3,
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0xd8, 0x48, 0x34,
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0xab, 0x0c} };
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static const MSGUID logical_sector_guid = { .data1 = 0x8141bf1d,
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.data2 = 0xa96f,
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.data3 = 0x4709,
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.data4 = { 0xba, 0x47, 0xf2,
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0x33, 0xa8, 0xfa,
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0xab, 0x5f} };
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/* Each parent type must have a valid GUID; this is for parent images
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* of type 'VHDX'. If we were to allow e.g. a QCOW2 parent, we would
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* need to make up our own QCOW2 GUID type */
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static const MSGUID parent_vhdx_guid __attribute__((unused))
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= { .data1 = 0xb04aefb7,
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.data2 = 0xd19e,
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.data3 = 0x4a81,
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.data4 = { 0xb7, 0x89, 0x25, 0xb8,
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0xe9, 0x44, 0x59, 0x13} };
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#define META_FILE_PARAMETER_PRESENT 0x01
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#define META_VIRTUAL_DISK_SIZE_PRESENT 0x02
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#define META_PAGE_83_PRESENT 0x04
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#define META_LOGICAL_SECTOR_SIZE_PRESENT 0x08
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#define META_PHYS_SECTOR_SIZE_PRESENT 0x10
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#define META_PARENT_LOCATOR_PRESENT 0x20
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#define META_ALL_PRESENT \
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(META_FILE_PARAMETER_PRESENT | META_VIRTUAL_DISK_SIZE_PRESENT | \
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META_PAGE_83_PRESENT | META_LOGICAL_SECTOR_SIZE_PRESENT | \
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META_PHYS_SECTOR_SIZE_PRESENT)
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typedef struct VHDXSectorInfo {
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uint32_t bat_idx; /* BAT entry index */
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uint32_t sectors_avail; /* sectors available in payload block */
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uint32_t bytes_left; /* bytes left in the block after data to r/w */
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uint32_t bytes_avail; /* bytes available in payload block */
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uint64_t file_offset; /* absolute offset in bytes, in file */
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uint64_t block_offset; /* block offset, in bytes */
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} VHDXSectorInfo;
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/* Calculates new checksum.
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*
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* Zero is substituted during crc calculation for the original crc field
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* crc_offset: byte offset in buf of the buffer crc
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* buf: buffer pointer
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* size: size of buffer (must be > crc_offset+4)
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*
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* Note: The buffer should have all multi-byte data in little-endian format,
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* and the resulting checksum is in little endian format.
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*/
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uint32_t vhdx_update_checksum(uint8_t *buf, size_t size, int crc_offset)
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{
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uint32_t crc;
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assert(buf != NULL);
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assert(size > (crc_offset + sizeof(crc)));
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memset(buf + crc_offset, 0, sizeof(crc));
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crc = crc32c(0xffffffff, buf, size);
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crc = cpu_to_le32(crc);
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memcpy(buf + crc_offset, &crc, sizeof(crc));
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return crc;
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}
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uint32_t vhdx_checksum_calc(uint32_t crc, uint8_t *buf, size_t size,
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int crc_offset)
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{
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uint32_t crc_new;
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uint32_t crc_orig;
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assert(buf != NULL);
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if (crc_offset > 0) {
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memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig));
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memset(buf + crc_offset, 0, sizeof(crc_orig));
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}
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crc_new = crc32c(crc, buf, size);
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if (crc_offset > 0) {
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memcpy(buf + crc_offset, &crc_orig, sizeof(crc_orig));
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}
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return crc_new;
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}
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/* Validates the checksum of the buffer, with an in-place CRC.
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*
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* Zero is substituted during crc calculation for the original crc field,
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* and the crc field is restored afterwards. But the buffer will be modified
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* during the calculation, so this may not be not suitable for multi-threaded
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* use.
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*
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* crc_offset: byte offset in buf of the buffer crc
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* buf: buffer pointer
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* size: size of buffer (must be > crc_offset+4)
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*
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* returns true if checksum is valid, false otherwise
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*/
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bool vhdx_checksum_is_valid(uint8_t *buf, size_t size, int crc_offset)
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{
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uint32_t crc_orig;
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uint32_t crc;
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assert(buf != NULL);
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assert(size > (crc_offset + 4));
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memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig));
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crc_orig = le32_to_cpu(crc_orig);
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crc = vhdx_checksum_calc(0xffffffff, buf, size, crc_offset);
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return crc == crc_orig;
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}
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/*
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* This generates a UUID that is compliant with the MS GUIDs used
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* in the VHDX spec (and elsewhere).
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*/
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void vhdx_guid_generate(MSGUID *guid)
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{
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QemuUUID uuid;
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assert(guid != NULL);
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qemu_uuid_generate(&uuid);
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memcpy(guid, &uuid, sizeof(MSGUID));
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}
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/* Check for region overlaps inside the VHDX image */
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static int vhdx_region_check(BDRVVHDXState *s, uint64_t start, uint64_t length)
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{
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int ret = 0;
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uint64_t end;
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VHDXRegionEntry *r;
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end = start + length;
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QLIST_FOREACH(r, &s->regions, entries) {
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if (!((start >= r->end) || (end <= r->start))) {
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error_report("VHDX region %" PRIu64 "-%" PRIu64 " overlaps with "
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"region %" PRIu64 "-%." PRIu64, start, end, r->start,
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r->end);
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ret = -EINVAL;
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goto exit;
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}
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}
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exit:
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return ret;
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}
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/* Register a region for future checks */
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static void vhdx_region_register(BDRVVHDXState *s,
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uint64_t start, uint64_t length)
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{
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VHDXRegionEntry *r;
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r = g_malloc0(sizeof(*r));
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r->start = start;
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r->end = start + length;
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QLIST_INSERT_HEAD(&s->regions, r, entries);
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}
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/* Free all registered regions */
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static void vhdx_region_unregister_all(BDRVVHDXState *s)
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{
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VHDXRegionEntry *r, *r_next;
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QLIST_FOREACH_SAFE(r, &s->regions, entries, r_next) {
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QLIST_REMOVE(r, entries);
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g_free(r);
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}
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}
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static void vhdx_set_shift_bits(BDRVVHDXState *s)
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{
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s->logical_sector_size_bits = ctz32(s->logical_sector_size);
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s->sectors_per_block_bits = ctz32(s->sectors_per_block);
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s->chunk_ratio_bits = ctz64(s->chunk_ratio);
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s->block_size_bits = ctz32(s->block_size);
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}
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/*
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* Per the MS VHDX Specification, for every VHDX file:
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* - The header section is fixed size - 1 MB
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* - The header section is always the first "object"
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* - The first 64KB of the header is the File Identifier
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* - The first uint64 (8 bytes) is the VHDX Signature ("vhdxfile")
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* - The following 512 bytes constitute a UTF-16 string identifiying the
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* software that created the file, and is optional and diagnostic only.
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*
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* Therefore, we probe by looking for the vhdxfile signature "vhdxfile"
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*/
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static int vhdx_probe(const uint8_t *buf, int buf_size, const char *filename)
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{
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if (buf_size >= 8 && !memcmp(buf, "vhdxfile", 8)) {
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return 100;
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}
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return 0;
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}
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/*
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* Writes the header to the specified offset.
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*
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* This will optionally read in buffer data from disk (otherwise zero-fill),
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* and then update the header checksum. Header is converted to proper
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* endianness before being written to the specified file offset
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*/
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static int vhdx_write_header(BdrvChild *file, VHDXHeader *hdr,
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uint64_t offset, bool read)
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{
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BlockDriverState *bs_file = file->bs;
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uint8_t *buffer = NULL;
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int ret;
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VHDXHeader *header_le;
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assert(bs_file != NULL);
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assert(hdr != NULL);
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|
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/* the header checksum is not over just the packed size of VHDXHeader,
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* but rather over the entire 'reserved' range for the header, which is
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* 4KB (VHDX_HEADER_SIZE). */
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buffer = qemu_blockalign(bs_file, VHDX_HEADER_SIZE);
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if (read) {
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/* if true, we can't assume the extra reserved bytes are 0 */
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ret = bdrv_pread(file, offset, VHDX_HEADER_SIZE, buffer, 0);
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if (ret < 0) {
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goto exit;
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}
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} else {
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memset(buffer, 0, VHDX_HEADER_SIZE);
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}
|
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|
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/* overwrite the actual VHDXHeader portion */
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header_le = (VHDXHeader *)buffer;
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memcpy(header_le, hdr, sizeof(VHDXHeader));
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vhdx_header_le_export(hdr, header_le);
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vhdx_update_checksum(buffer, VHDX_HEADER_SIZE,
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offsetof(VHDXHeader, checksum));
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ret = bdrv_pwrite_sync(file, offset, sizeof(VHDXHeader), header_le, 0);
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|
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exit:
|
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qemu_vfree(buffer);
|
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return ret;
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}
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|
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/* Update the VHDX headers
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*
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* This follows the VHDX spec procedures for header updates.
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*
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* - non-current header is updated with largest sequence number
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*/
|
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static int vhdx_update_header(BlockDriverState *bs, BDRVVHDXState *s,
|
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bool generate_data_write_guid, MSGUID *log_guid)
|
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{
|
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int ret = 0;
|
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int hdr_idx = 0;
|
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uint64_t header_offset = VHDX_HEADER1_OFFSET;
|
|
|
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VHDXHeader *active_header;
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VHDXHeader *inactive_header;
|
|
|
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/* operate on the non-current header */
|
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if (s->curr_header == 0) {
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hdr_idx = 1;
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header_offset = VHDX_HEADER2_OFFSET;
|
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}
|
|
|
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active_header = s->headers[s->curr_header];
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inactive_header = s->headers[hdr_idx];
|
|
|
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inactive_header->sequence_number = active_header->sequence_number + 1;
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|
|
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/* a new file guid must be generated before any file write, including
|
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* headers */
|
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inactive_header->file_write_guid = s->session_guid;
|
|
|
|
/* a new data guid only needs to be generated before any guest-visible
|
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* writes (i.e. something observable via virtual disk read) */
|
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if (generate_data_write_guid) {
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vhdx_guid_generate(&inactive_header->data_write_guid);
|
|
}
|
|
|
|
/* update the log guid if present */
|
|
if (log_guid) {
|
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inactive_header->log_guid = *log_guid;
|
|
}
|
|
|
|
ret = vhdx_write_header(bs->file, 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
|
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* the current and non-current header have valid info
|
|
*/
|
|
int vhdx_update_headers(BlockDriverState *bs, BDRVVHDXState *s,
|
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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;
|
|
}
|
|
return vhdx_update_header(bs, s, generate_data_write_guid, log_guid);
|
|
}
|
|
|
|
/* 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, VHDX_HEADER1_OFFSET, VHDX_HEADER_SIZE, buffer,
|
|
0);
|
|
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 &&
|
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header1->version == 1) {
|
|
h1_seq = header1->sequence_number;
|
|
h1_valid = true;
|
|
}
|
|
}
|
|
|
|
ret = bdrv_pread(bs->file, VHDX_HEADER2_OFFSET, VHDX_HEADER_SIZE, buffer,
|
|
0);
|
|
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, VHDX_REGION_TABLE_OFFSET,
|
|
VHDX_HEADER_BLOCK_SIZE, buffer, 0);
|
|
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, s->metadata_rt.file_offset,
|
|
VHDX_METADATA_TABLE_MAX_SIZE, buffer, 0);
|
|
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,
|
|
s->metadata_entries.file_parameters_entry.offset
|
|
+ s->metadata_rt.file_offset,
|
|
sizeof(s->params),
|
|
&s->params,
|
|
0);
|
|
|
|
if (ret < 0) {
|
|
goto exit;
|
|
}
|
|
|
|
s->params.block_size = le32_to_cpu(s->params.block_size);
|
|
s->params.data_bits = le32_to_cpu(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,
|
|
s->metadata_entries.virtual_disk_size_entry.offset
|
|
+ s->metadata_rt.file_offset,
|
|
sizeof(uint64_t),
|
|
&s->virtual_disk_size,
|
|
0);
|
|
if (ret < 0) {
|
|
goto exit;
|
|
}
|
|
ret = bdrv_pread(bs->file,
|
|
s->metadata_entries.logical_sector_size_entry.offset
|
|
+ s->metadata_rt.file_offset,
|
|
sizeof(uint32_t),
|
|
&s->logical_sector_size,
|
|
0);
|
|
if (ret < 0) {
|
|
goto exit;
|
|
}
|
|
ret = bdrv_pread(bs->file,
|
|
s->metadata_entries.phys_sector_size_entry.offset
|
|
+ s->metadata_rt.file_offset,
|
|
sizeof(uint32_t),
|
|
&s->physical_sector_size,
|
|
0);
|
|
if (ret < 0) {
|
|
goto exit;
|
|
}
|
|
|
|
s->virtual_disk_size = le64_to_cpu(s->virtual_disk_size);
|
|
s->logical_sector_size = le32_to_cpu(s->logical_sector_size);
|
|
s->physical_sector_size = le32_to_cpu(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;
|
|
}
|
|
|
|
/* Currently we only support 512 */
|
|
if (s->logical_sector_size != 512) {
|
|
ret = -ENOTSUP;
|
|
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 int vhdx_check_bat_entries(BlockDriverState *bs, int *errcnt)
|
|
{
|
|
BDRVVHDXState *s = bs->opaque;
|
|
int64_t image_file_size = bdrv_getlength(bs->file->bs);
|
|
uint64_t payblocks = s->chunk_ratio;
|
|
uint64_t i;
|
|
int ret = 0;
|
|
|
|
if (image_file_size < 0) {
|
|
error_report("Could not determinate VHDX image file size.");
|
|
return image_file_size;
|
|
}
|
|
|
|
for (i = 0; i < s->bat_entries; i++) {
|
|
if ((s->bat[i] & VHDX_BAT_STATE_BIT_MASK) ==
|
|
PAYLOAD_BLOCK_FULLY_PRESENT) {
|
|
uint64_t offset = s->bat[i] & VHDX_BAT_FILE_OFF_MASK;
|
|
/*
|
|
* Allow that the last block exists only partially. The VHDX spec
|
|
* states that the image file can only grow in blocksize increments,
|
|
* but QEMU created images with partial last blocks in the past.
|
|
*/
|
|
uint32_t block_length = MIN(s->block_size,
|
|
bs->total_sectors * BDRV_SECTOR_SIZE - i * s->block_size);
|
|
/*
|
|
* Check for BAT entry overflow.
|
|
*/
|
|
if (offset > INT64_MAX - s->block_size) {
|
|
error_report("VHDX BAT entry %" PRIu64 " offset overflow.", i);
|
|
ret = -EINVAL;
|
|
if (!errcnt) {
|
|
break;
|
|
}
|
|
(*errcnt)++;
|
|
}
|
|
/*
|
|
* Check if fully allocated BAT entries do not reside after
|
|
* end of the image file.
|
|
*/
|
|
if (offset >= image_file_size) {
|
|
error_report("VHDX BAT entry %" PRIu64 " start offset %" PRIu64
|
|
" points after end of file (%" PRIi64 "). Image"
|
|
" has probably been truncated.",
|
|
i, offset, image_file_size);
|
|
ret = -EINVAL;
|
|
if (!errcnt) {
|
|
break;
|
|
}
|
|
(*errcnt)++;
|
|
} else if (offset + block_length > image_file_size) {
|
|
error_report("VHDX BAT entry %" PRIu64 " end offset %" PRIu64
|
|
" points after end of file (%" PRIi64 "). Image"
|
|
" has probably been truncated.",
|
|
i, offset + block_length - 1, image_file_size);
|
|
ret = -EINVAL;
|
|
if (!errcnt) {
|
|
break;
|
|
}
|
|
(*errcnt)++;
|
|
}
|
|
|
|
/*
|
|
* verify populated BAT field file offsets against
|
|
* region table and log entries
|
|
*/
|
|
if (payblocks--) {
|
|
/* payload bat entries */
|
|
int ret2;
|
|
ret2 = vhdx_region_check(s, offset, s->block_size);
|
|
if (ret2 < 0) {
|
|
ret = -EINVAL;
|
|
if (!errcnt) {
|
|
break;
|
|
}
|
|
(*errcnt)++;
|
|
}
|
|
} else {
|
|
payblocks = s->chunk_ratio;
|
|
/*
|
|
* Once differencing files are supported, verify sector bitmap
|
|
* blocks here
|
|
*/
|
|
}
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
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;
|
|
|
|
ret = bdrv_open_file_child(NULL, options, "file", bs, errp);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
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, 0, sizeof(uint64_t), &signature, 0);
|
|
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, s->bat_offset, s->bat_rt.length, s->bat, 0);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
|
|
/* endian convert populated BAT field entires */
|
|
for (i = 0; i < s->bat_entries; i++) {
|
|
s->bat[i] = le64_to_cpu(s->bat[i]);
|
|
}
|
|
|
|
if (!(flags & BDRV_O_CHECK)) {
|
|
ret = vhdx_check_bat_entries(bs, NULL);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
}
|
|
|
|
/* 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));
|
|
ret = migrate_add_blocker(s->migration_blocker, errp);
|
|
if (ret < 0) {
|
|
error_free(s->migration_blocker);
|
|
goto fail;
|
|
}
|
|
|
|
/* TODO: differencing files */
|
|
|
|
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;
|
|
|
|
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_preadv(bs->file, sinfo.file_offset,
|
|
sinfo.sectors_avail * BDRV_SECTOR_SIZE,
|
|
&hd_qiov, 0);
|
|
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.
|
|
*
|
|
* If @need_zero is set on entry but not cleared on return, then truncation
|
|
* could not guarantee that the new portion reads as zero, and the caller
|
|
* will take care of it instead.
|
|
*
|
|
* Returns the file offset start of the new payload block
|
|
*/
|
|
static int vhdx_allocate_block(BlockDriverState *bs, BDRVVHDXState *s,
|
|
uint64_t *new_offset, bool *need_zero)
|
|
{
|
|
int64_t current_len;
|
|
|
|
current_len = bdrv_getlength(bs->file->bs);
|
|
if (current_len < 0) {
|
|
return current_len;
|
|
}
|
|
|
|
*new_offset = current_len;
|
|
|
|
/* per the spec, the address for a block is in units of 1MB */
|
|
*new_offset = ROUND_UP(*new_offset, 1 * MiB);
|
|
if (*new_offset > INT64_MAX) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (*need_zero) {
|
|
int ret;
|
|
|
|
ret = bdrv_truncate(bs->file, *new_offset + s->block_size, false,
|
|
PREALLOC_MODE_OFF, BDRV_REQ_ZERO_WRITE, NULL);
|
|
if (ret != -ENOTSUP) {
|
|
*need_zero = false;
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
return bdrv_truncate(bs->file, *new_offset + s->block_size, false,
|
|
PREALLOC_MODE_OFF, 0, NULL);
|
|
}
|
|
|
|
/*
|
|
* 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 flags)
|
|
{
|
|
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 */
|
|
use_zero_buffers = true;
|
|
/* 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,
|
|
&use_zero_buffers);
|
|
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, unless the entire block needs to read as
|
|
* zeroes but truncation was not able to provide them,
|
|
* in which case we need to fill in the rest.
|
|
*/
|
|
if (!use_zero_buffers) {
|
|
sinfo.file_offset += sinfo.block_offset;
|
|
} else {
|
|
/* 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_FULLY_PRESENT:
|
|
/* if the file offset address is in the header zone,
|
|
* there is a problem */
|
|
if (sinfo.file_offset < (1 * MiB)) {
|
|
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_pwritev(bs->file, sinfo.file_offset,
|
|
sectors_to_write * BDRV_SECTOR_SIZE,
|
|
&hd_qiov, 0);
|
|
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(BlockBackend *blk, uint64_t image_size,
|
|
uint32_t log_size)
|
|
{
|
|
BlockDriverState *bs = blk_bs(blk);
|
|
BdrvChild *child;
|
|
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);
|
|
|
|
/* XXX Ugly way to get blk->root, but that's a feature, not a bug. This
|
|
* hack makes it obvious that vhdx_write_header() bypasses the BlockBackend
|
|
* here, which it really shouldn't be doing. */
|
|
child = QLIST_FIRST(&bs->parents);
|
|
assert(!QLIST_NEXT(child, next_parent));
|
|
|
|
ret = vhdx_write_header(child, hdr, VHDX_HEADER1_OFFSET, false);
|
|
if (ret < 0) {
|
|
goto exit;
|
|
}
|
|
hdr->sequence_number++;
|
|
ret = vhdx_write_header(child, 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(BlockBackend *blk,
|
|
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;
|
|
mt_file_params->data_bits = cpu_to_le32(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 = blk_pwrite(blk, metadata_offset, VHDX_HEADER_BLOCK_SIZE, buffer, 0);
|
|
if (ret < 0) {
|
|
goto exit;
|
|
}
|
|
|
|
ret = blk_pwrite(blk, metadata_offset + (64 * KiB),
|
|
VHDX_METADATA_ENTRY_BUFFER_SIZE, entry_buffer, 0);
|
|
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(BlockBackend *blk, BDRVVHDXState *s,
|
|
uint64_t image_size, VHDXImageType type,
|
|
bool use_zero_blocks, uint64_t file_offset,
|
|
uint32_t length, Error **errp)
|
|
{
|
|
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 = blk_truncate(blk, data_file_offset, false, PREALLOC_MODE_OFF,
|
|
0, errp);
|
|
if (ret < 0) {
|
|
goto exit;
|
|
}
|
|
} else if (type == VHDX_TYPE_FIXED) {
|
|
ret = blk_truncate(blk, data_file_offset + image_size, false,
|
|
PREALLOC_MODE_OFF, 0, errp);
|
|
if (ret < 0) {
|
|
goto exit;
|
|
}
|
|
} else {
|
|
error_setg(errp, "Unsupported image type");
|
|
ret = -ENOTSUP;
|
|
goto exit;
|
|
}
|
|
|
|
if (type == VHDX_TYPE_FIXED ||
|
|
use_zero_blocks ||
|
|
bdrv_has_zero_init(blk_bs(blk)) == 0) {
|
|
/* for a fixed file, the default BAT entry is not zero */
|
|
s->bat = g_try_malloc0(length);
|
|
if (length && s->bat == NULL) {
|
|
error_setg(errp, "Failed to allocate memory for the BAT");
|
|
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(blk_bs(blk), s, &sinfo, &unused, &unused,
|
|
block_state);
|
|
s->bat[sinfo.bat_idx] = cpu_to_le64(s->bat[sinfo.bat_idx]);
|
|
sector_num += s->sectors_per_block;
|
|
}
|
|
ret = blk_pwrite(blk, file_offset, length, s->bat, 0);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Failed to write the BAT");
|
|
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(BlockBackend *blk,
|
|
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,
|
|
Error **errp)
|
|
{
|
|
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(blk, s, image_size, type, use_zero_blocks,
|
|
bat_file_offset, bat_length, errp);
|
|
if (ret < 0) {
|
|
goto exit;
|
|
}
|
|
|
|
/* Now write out the region headers to disk */
|
|
ret = blk_pwrite(blk, VHDX_REGION_TABLE_OFFSET, VHDX_HEADER_BLOCK_SIZE,
|
|
buffer, 0);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Failed to write first region table");
|
|
goto exit;
|
|
}
|
|
|
|
ret = blk_pwrite(blk, VHDX_REGION_TABLE2_OFFSET, VHDX_HEADER_BLOCK_SIZE,
|
|
buffer, 0);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Failed to write second region table");
|
|
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 coroutine_fn vhdx_co_create(BlockdevCreateOptions *opts,
|
|
Error **errp)
|
|
{
|
|
BlockdevCreateOptionsVhdx *vhdx_opts;
|
|
BlockBackend *blk = NULL;
|
|
BlockDriverState *bs = NULL;
|
|
|
|
int ret = 0;
|
|
uint64_t image_size;
|
|
uint32_t log_size;
|
|
uint32_t block_size;
|
|
uint64_t signature;
|
|
uint64_t metadata_offset;
|
|
bool use_zero_blocks = false;
|
|
|
|
gunichar2 *creator = NULL;
|
|
glong creator_items;
|
|
VHDXImageType image_type;
|
|
|
|
assert(opts->driver == BLOCKDEV_DRIVER_VHDX);
|
|
vhdx_opts = &opts->u.vhdx;
|
|
|
|
/* Validate options and set default values */
|
|
image_size = vhdx_opts->size;
|
|
if (image_size > VHDX_MAX_IMAGE_SIZE) {
|
|
error_setg(errp, "Image size too large; max of 64TB");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!vhdx_opts->has_log_size) {
|
|
log_size = DEFAULT_LOG_SIZE;
|
|
} else {
|
|
if (vhdx_opts->log_size > UINT32_MAX) {
|
|
error_setg(errp, "Log size must be smaller than 4 GB");
|
|
return -EINVAL;
|
|
}
|
|
log_size = vhdx_opts->log_size;
|
|
}
|
|
if (log_size < MiB || (log_size % MiB) != 0) {
|
|
error_setg(errp, "Log size must be a multiple of 1 MB");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!vhdx_opts->has_block_state_zero) {
|
|
use_zero_blocks = true;
|
|
} else {
|
|
use_zero_blocks = vhdx_opts->block_state_zero;
|
|
}
|
|
|
|
if (!vhdx_opts->has_subformat) {
|
|
vhdx_opts->subformat = BLOCKDEV_VHDX_SUBFORMAT_DYNAMIC;
|
|
}
|
|
|
|
switch (vhdx_opts->subformat) {
|
|
case BLOCKDEV_VHDX_SUBFORMAT_DYNAMIC:
|
|
image_type = VHDX_TYPE_DYNAMIC;
|
|
break;
|
|
case BLOCKDEV_VHDX_SUBFORMAT_FIXED:
|
|
image_type = VHDX_TYPE_FIXED;
|
|
break;
|
|
default:
|
|
g_assert_not_reached();
|
|
}
|
|
|
|
/* These are pretty arbitrary, and mainly designed to keep the BAT
|
|
* size reasonable to load into RAM */
|
|
if (vhdx_opts->has_block_size) {
|
|
block_size = vhdx_opts->block_size;
|
|
} else {
|
|
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;
|
|
}
|
|
}
|
|
|
|
if (block_size < MiB || (block_size % MiB) != 0) {
|
|
error_setg(errp, "Block size must be a multiple of 1 MB");
|
|
return -EINVAL;
|
|
}
|
|
if (!is_power_of_2(block_size)) {
|
|
error_setg(errp, "Block size must be a power of two");
|
|
return -EINVAL;
|
|
}
|
|
if (block_size > VHDX_BLOCK_SIZE_MAX) {
|
|
error_setg(errp, "Block size must not exceed %" PRId64,
|
|
VHDX_BLOCK_SIZE_MAX);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Create BlockBackend to write to the image */
|
|
bs = bdrv_open_blockdev_ref(vhdx_opts->file, errp);
|
|
if (bs == NULL) {
|
|
return -EIO;
|
|
}
|
|
|
|
blk = blk_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL,
|
|
errp);
|
|
if (!blk) {
|
|
ret = -EPERM;
|
|
goto delete_and_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_co_pwrite(blk, VHDX_FILE_ID_OFFSET, sizeof(signature), &signature,
|
|
0);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Failed to write file signature");
|
|
goto delete_and_exit;
|
|
}
|
|
if (creator) {
|
|
ret = blk_co_pwrite(blk, VHDX_FILE_ID_OFFSET + sizeof(signature),
|
|
creator_items * sizeof(gunichar2), creator, 0);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Failed to write creator field");
|
|
goto delete_and_exit;
|
|
}
|
|
}
|
|
|
|
|
|
/* Creates (B),(C) */
|
|
ret = vhdx_create_new_headers(blk, image_size, log_size);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Failed to write image headers");
|
|
goto delete_and_exit;
|
|
}
|
|
|
|
/* Creates (D),(E),(G) explicitly. (F) created as by-product */
|
|
ret = vhdx_create_new_region_table(blk, image_size, block_size, 512,
|
|
log_size, use_zero_blocks, image_type,
|
|
&metadata_offset, errp);
|
|
if (ret < 0) {
|
|
goto delete_and_exit;
|
|
}
|
|
|
|
/* Creates (H) */
|
|
ret = vhdx_create_new_metadata(blk, image_size, block_size, 512,
|
|
metadata_offset, image_type);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret, "Failed to initialize metadata");
|
|
goto delete_and_exit;
|
|
}
|
|
|
|
ret = 0;
|
|
delete_and_exit:
|
|
blk_unref(blk);
|
|
bdrv_unref(bs);
|
|
g_free(creator);
|
|
return ret;
|
|
}
|
|
|
|
static int coroutine_fn vhdx_co_create_opts(BlockDriver *drv,
|
|
const char *filename,
|
|
QemuOpts *opts,
|
|
Error **errp)
|
|
{
|
|
BlockdevCreateOptions *create_options = NULL;
|
|
QDict *qdict;
|
|
Visitor *v;
|
|
BlockDriverState *bs = NULL;
|
|
int ret;
|
|
|
|
static const QDictRenames opt_renames[] = {
|
|
{ VHDX_BLOCK_OPT_LOG_SIZE, "log-size" },
|
|
{ VHDX_BLOCK_OPT_BLOCK_SIZE, "block-size" },
|
|
{ VHDX_BLOCK_OPT_ZERO, "block-state-zero" },
|
|
{ NULL, NULL },
|
|
};
|
|
|
|
/* Parse options and convert legacy syntax */
|
|
qdict = qemu_opts_to_qdict_filtered(opts, NULL, &vhdx_create_opts, true);
|
|
|
|
if (!qdict_rename_keys(qdict, opt_renames, errp)) {
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
/* Create and open the file (protocol layer) */
|
|
ret = bdrv_create_file(filename, opts, errp);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
|
|
bs = bdrv_open(filename, NULL, NULL,
|
|
BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, errp);
|
|
if (bs == NULL) {
|
|
ret = -EIO;
|
|
goto fail;
|
|
}
|
|
|
|
/* Now get the QAPI type BlockdevCreateOptions */
|
|
qdict_put_str(qdict, "driver", "vhdx");
|
|
qdict_put_str(qdict, "file", bs->node_name);
|
|
|
|
v = qobject_input_visitor_new_flat_confused(qdict, errp);
|
|
if (!v) {
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
visit_type_BlockdevCreateOptions(v, NULL, &create_options, errp);
|
|
visit_free(v);
|
|
if (!create_options) {
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
/* Silently round up sizes:
|
|
* The image size is rounded to 512 bytes. Make the block and log size
|
|
* close to what was specified, but must be at least 1MB, and a multiple of
|
|
* 1 MB. Also respect VHDX_BLOCK_SIZE_MAX for block sizes. block_size = 0
|
|
* means auto, which is represented by a missing key in QAPI. */
|
|
assert(create_options->driver == BLOCKDEV_DRIVER_VHDX);
|
|
create_options->u.vhdx.size =
|
|
ROUND_UP(create_options->u.vhdx.size, BDRV_SECTOR_SIZE);
|
|
|
|
if (create_options->u.vhdx.has_log_size) {
|
|
create_options->u.vhdx.log_size =
|
|
ROUND_UP(create_options->u.vhdx.log_size, MiB);
|
|
}
|
|
if (create_options->u.vhdx.has_block_size) {
|
|
create_options->u.vhdx.block_size =
|
|
ROUND_UP(create_options->u.vhdx.block_size, MiB);
|
|
|
|
if (create_options->u.vhdx.block_size == 0) {
|
|
create_options->u.vhdx.has_block_size = false;
|
|
}
|
|
if (create_options->u.vhdx.block_size > VHDX_BLOCK_SIZE_MAX) {
|
|
create_options->u.vhdx.block_size = VHDX_BLOCK_SIZE_MAX;
|
|
}
|
|
}
|
|
|
|
/* Create the vhdx image (format layer) */
|
|
ret = vhdx_co_create(create_options, errp);
|
|
|
|
fail:
|
|
qobject_unref(qdict);
|
|
bdrv_unref(bs);
|
|
qapi_free_BlockdevCreateOptions(create_options);
|
|
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 coroutine_fn vhdx_co_check(BlockDriverState *bs,
|
|
BdrvCheckResult *result,
|
|
BdrvCheckMode fix)
|
|
{
|
|
BDRVVHDXState *s = bs->opaque;
|
|
|
|
if (s->log_replayed_on_open) {
|
|
result->corruptions_fixed++;
|
|
}
|
|
|
|
vhdx_check_bat_entries(bs, &result->corruptions);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int vhdx_has_zero_init(BlockDriverState *bs)
|
|
{
|
|
BDRVVHDXState *s = bs->opaque;
|
|
int state;
|
|
|
|
/*
|
|
* Check the subformat: Fixed images have all BAT entries present,
|
|
* dynamic images have none (right after creation). It is
|
|
* therefore enough to check the first BAT entry.
|
|
*/
|
|
if (!s->bat_entries) {
|
|
return 1;
|
|
}
|
|
|
|
state = s->bat[0] & VHDX_BAT_STATE_BIT_MASK;
|
|
if (state == PAYLOAD_BLOCK_FULLY_PRESENT) {
|
|
/* Fixed subformat */
|
|
return bdrv_has_zero_init(bs->file->bs);
|
|
}
|
|
|
|
/* Dynamic subformat */
|
|
return 1;
|
|
}
|
|
|
|
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_child_perm = bdrv_default_perms,
|
|
.bdrv_co_readv = vhdx_co_readv,
|
|
.bdrv_co_writev = vhdx_co_writev,
|
|
.bdrv_co_create = vhdx_co_create,
|
|
.bdrv_co_create_opts = vhdx_co_create_opts,
|
|
.bdrv_get_info = vhdx_get_info,
|
|
.bdrv_co_check = vhdx_co_check,
|
|
.bdrv_has_zero_init = vhdx_has_zero_init,
|
|
|
|
.is_format = true,
|
|
.create_opts = &vhdx_create_opts,
|
|
};
|
|
|
|
static void bdrv_vhdx_init(void)
|
|
{
|
|
bdrv_register(&bdrv_vhdx);
|
|
}
|
|
|
|
block_init(bdrv_vhdx_init);
|