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/*
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* Block driver for the Virtual Disk Image (VDI) format
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*
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* Copyright (c) 2009, 2012 Stefan Weil
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 2 of the License, or
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* (at your option) version 3 or any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*
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* Reference:
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* http://forums.virtualbox.org/viewtopic.php?t=8046
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*
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* This driver supports create / read / write operations on VDI images.
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*
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* Todo (see also TODO in code):
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*
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* Some features like snapshots are still missing.
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*
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* Deallocation of zero-filled blocks and shrinking images are missing, too
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* (might be added to common block layer).
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*
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* Allocation of blocks could be optimized (less writes to block map and
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* header).
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*
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* Read and write of adjacents blocks could be done in one operation
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* (current code uses one operation per block (1 MiB).
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*
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* The code is not thread safe (missing locks for changes in header and
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* block table, no problem with current QEMU).
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*
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* Hints:
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*
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* Blocks (VDI documentation) correspond to clusters (QEMU).
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* QEMU's backing files could be implemented using VDI snapshot files (TODO).
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* VDI snapshot files may also contain the complete machine state.
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* Maybe this machine state can be converted to QEMU PC machine snapshot data.
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*
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* The driver keeps a block cache (little endian entries) in memory.
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* For the standard block size (1 MiB), a 1 TiB disk will use 4 MiB RAM,
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* so this seems to be reasonable.
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*/
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#include "qemu-common.h" |
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#include "block/block_int.h" |
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#include "qemu/module.h" |
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#include "migration/migration.h" |
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#if defined(CONFIG_UUID)
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#include <uuid/uuid.h> |
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#else
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/* TODO: move uuid emulation to some central place in QEMU. */
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#include "sysemu/sysemu.h" /* UUID_FMT */ |
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typedef unsigned char uuid_t[16]; |
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#endif
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/* Code configuration options. */
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/* Enable debug messages. */
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//~ #define CONFIG_VDI_DEBUG
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/* Support write operations on VDI images. */
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#define CONFIG_VDI_WRITE
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/* Support non-standard block (cluster) size. This is untested.
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* Maybe it will be needed for very large images.
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*/
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//~ #define CONFIG_VDI_BLOCK_SIZE
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/* Support static (fixed, pre-allocated) images. */
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#define CONFIG_VDI_STATIC_IMAGE
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/* Command line option for static images. */
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#define BLOCK_OPT_STATIC "static" |
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#define KiB 1024 |
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#define MiB (KiB * KiB)
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#define SECTOR_SIZE 512 |
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#define DEFAULT_CLUSTER_SIZE (1 * MiB) |
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#if defined(CONFIG_VDI_DEBUG)
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#define logout(fmt, ...) \
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fprintf(stderr, "vdi\t%-24s" fmt, __func__, ##__VA_ARGS__) |
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#else
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#define logout(fmt, ...) ((void)0) |
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#endif
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/* Image signature. */
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#define VDI_SIGNATURE 0xbeda107f |
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/* Image version. */
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#define VDI_VERSION_1_1 0x00010001 |
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/* Image type. */
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#define VDI_TYPE_DYNAMIC 1 |
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#define VDI_TYPE_STATIC 2 |
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/* Innotek / SUN images use these strings in header.text:
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* "<<< innotek VirtualBox Disk Image >>>\n"
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* "<<< Sun xVM VirtualBox Disk Image >>>\n"
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* "<<< Sun VirtualBox Disk Image >>>\n"
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* The value does not matter, so QEMU created images use a different text.
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*/
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#define VDI_TEXT "<<< QEMU VM Virtual Disk Image >>>\n" |
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/* A never-allocated block; semantically arbitrary content. */
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#define VDI_UNALLOCATED 0xffffffffU |
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/* A discarded (no longer allocated) block; semantically zero-filled. */
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#define VDI_DISCARDED 0xfffffffeU |
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#define VDI_IS_ALLOCATED(X) ((X) < VDI_DISCARDED)
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#if !defined(CONFIG_UUID)
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static inline void uuid_generate(uuid_t out) |
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{ |
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memset(out, 0, sizeof(uuid_t)); |
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} |
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static inline int uuid_is_null(const uuid_t uu) |
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{ |
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uuid_t null_uuid = { 0 };
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return memcmp(uu, null_uuid, sizeof(uuid_t)) == 0; |
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} |
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static inline void uuid_unparse(const uuid_t uu, char *out) |
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{ |
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snprintf(out, 37, UUID_FMT,
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uu[0], uu[1], uu[2], uu[3], uu[4], uu[5], uu[6], uu[7], |
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uu[8], uu[9], uu[10], uu[11], uu[12], uu[13], uu[14], uu[15]); |
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} |
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#endif
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typedef struct { |
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char text[0x40]; |
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uint32_t signature; |
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uint32_t version; |
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uint32_t header_size; |
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uint32_t image_type; |
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uint32_t image_flags; |
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char description[256]; |
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uint32_t offset_bmap; |
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uint32_t offset_data; |
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uint32_t cylinders; /* disk geometry, unused here */
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uint32_t heads; /* disk geometry, unused here */
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uint32_t sectors; /* disk geometry, unused here */
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uint32_t sector_size; |
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uint32_t unused1; |
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uint64_t disk_size; |
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uint32_t block_size; |
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uint32_t block_extra; /* unused here */
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uint32_t blocks_in_image; |
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uint32_t blocks_allocated; |
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uuid_t uuid_image; |
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uuid_t uuid_last_snap; |
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uuid_t uuid_link; |
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uuid_t uuid_parent; |
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uint64_t unused2[7];
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} VdiHeader; |
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typedef struct { |
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/* The block map entries are little endian (even in memory). */
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uint32_t *bmap; |
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/* Size of block (bytes). */
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uint32_t block_size; |
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/* Size of block (sectors). */
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uint32_t block_sectors; |
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/* First sector of block map. */
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uint32_t bmap_sector; |
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/* VDI header (converted to host endianness). */
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VdiHeader header; |
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Error *migration_blocker; |
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} BDRVVdiState; |
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/* Change UUID from little endian (IPRT = VirtualBox format) to big endian
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* format (network byte order, standard, see RFC 4122) and vice versa.
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*/
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static void uuid_convert(uuid_t uuid) |
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{ |
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bswap32s((uint32_t *)&uuid[0]);
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bswap16s((uint16_t *)&uuid[4]);
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bswap16s((uint16_t *)&uuid[6]);
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} |
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static void vdi_header_to_cpu(VdiHeader *header) |
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{ |
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le32_to_cpus(&header->signature); |
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le32_to_cpus(&header->version); |
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le32_to_cpus(&header->header_size); |
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le32_to_cpus(&header->image_type); |
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le32_to_cpus(&header->image_flags); |
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le32_to_cpus(&header->offset_bmap); |
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le32_to_cpus(&header->offset_data); |
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le32_to_cpus(&header->cylinders); |
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le32_to_cpus(&header->heads); |
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le32_to_cpus(&header->sectors); |
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le32_to_cpus(&header->sector_size); |
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le64_to_cpus(&header->disk_size); |
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le32_to_cpus(&header->block_size); |
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le32_to_cpus(&header->block_extra); |
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le32_to_cpus(&header->blocks_in_image); |
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le32_to_cpus(&header->blocks_allocated); |
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uuid_convert(header->uuid_image); |
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uuid_convert(header->uuid_last_snap); |
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uuid_convert(header->uuid_link); |
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uuid_convert(header->uuid_parent); |
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} |
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static void vdi_header_to_le(VdiHeader *header) |
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{ |
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cpu_to_le32s(&header->signature); |
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cpu_to_le32s(&header->version); |
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cpu_to_le32s(&header->header_size); |
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cpu_to_le32s(&header->image_type); |
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cpu_to_le32s(&header->image_flags); |
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cpu_to_le32s(&header->offset_bmap); |
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cpu_to_le32s(&header->offset_data); |
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cpu_to_le32s(&header->cylinders); |
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cpu_to_le32s(&header->heads); |
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cpu_to_le32s(&header->sectors); |
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cpu_to_le32s(&header->sector_size); |
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cpu_to_le64s(&header->disk_size); |
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cpu_to_le32s(&header->block_size); |
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cpu_to_le32s(&header->block_extra); |
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cpu_to_le32s(&header->blocks_in_image); |
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cpu_to_le32s(&header->blocks_allocated); |
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cpu_to_le32s(&header->blocks_allocated); |
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uuid_convert(header->uuid_image); |
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uuid_convert(header->uuid_last_snap); |
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uuid_convert(header->uuid_link); |
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uuid_convert(header->uuid_parent); |
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} |
243 |
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#if defined(CONFIG_VDI_DEBUG)
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static void vdi_header_print(VdiHeader *header) |
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{ |
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char uuid[37]; |
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logout("text %s", header->text);
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logout("signature 0x%04x\n", header->signature);
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logout("header size 0x%04x\n", header->header_size);
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logout("image type 0x%04x\n", header->image_type);
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logout("image flags 0x%04x\n", header->image_flags);
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logout("description %s\n", header->description);
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logout("offset bmap 0x%04x\n", header->offset_bmap);
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logout("offset data 0x%04x\n", header->offset_data);
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logout("cylinders 0x%04x\n", header->cylinders);
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logout("heads 0x%04x\n", header->heads);
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logout("sectors 0x%04x\n", header->sectors);
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logout("sector size 0x%04x\n", header->sector_size);
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logout("image size 0x%" PRIx64 " B (%" PRIu64 " MiB)\n", |
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header->disk_size, header->disk_size / MiB); |
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logout("block size 0x%04x\n", header->block_size);
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logout("block extra 0x%04x\n", header->block_extra);
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logout("blocks tot. 0x%04x\n", header->blocks_in_image);
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logout("blocks all. 0x%04x\n", header->blocks_allocated);
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uuid_unparse(header->uuid_image, uuid); |
267 |
logout("uuid image %s\n", uuid);
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uuid_unparse(header->uuid_last_snap, uuid); |
269 |
logout("uuid snap %s\n", uuid);
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uuid_unparse(header->uuid_link, uuid); |
271 |
logout("uuid link %s\n", uuid);
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uuid_unparse(header->uuid_parent, uuid); |
273 |
logout("uuid parent %s\n", uuid);
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} |
275 |
#endif
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276 |
|
277 |
static int vdi_check(BlockDriverState *bs, BdrvCheckResult *res, |
278 |
BdrvCheckMode fix) |
279 |
{ |
280 |
/* TODO: additional checks possible. */
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281 |
BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
282 |
uint32_t blocks_allocated = 0;
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283 |
uint32_t block; |
284 |
uint32_t *bmap; |
285 |
logout("\n");
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286 |
|
287 |
if (fix) {
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288 |
return -ENOTSUP;
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289 |
} |
290 |
|
291 |
bmap = g_malloc(s->header.blocks_in_image * sizeof(uint32_t));
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292 |
memset(bmap, 0xff, s->header.blocks_in_image * sizeof(uint32_t)); |
293 |
|
294 |
/* Check block map and value of blocks_allocated. */
|
295 |
for (block = 0; block < s->header.blocks_in_image; block++) { |
296 |
uint32_t bmap_entry = le32_to_cpu(s->bmap[block]); |
297 |
if (VDI_IS_ALLOCATED(bmap_entry)) {
|
298 |
if (bmap_entry < s->header.blocks_in_image) {
|
299 |
blocks_allocated++; |
300 |
if (!VDI_IS_ALLOCATED(bmap[bmap_entry])) {
|
301 |
bmap[bmap_entry] = bmap_entry; |
302 |
} else {
|
303 |
fprintf(stderr, "ERROR: block index %" PRIu32
|
304 |
" also used by %" PRIu32 "\n", bmap[bmap_entry], bmap_entry); |
305 |
res->corruptions++; |
306 |
} |
307 |
} else {
|
308 |
fprintf(stderr, "ERROR: block index %" PRIu32
|
309 |
" too large, is %" PRIu32 "\n", block, bmap_entry); |
310 |
res->corruptions++; |
311 |
} |
312 |
} |
313 |
} |
314 |
if (blocks_allocated != s->header.blocks_allocated) {
|
315 |
fprintf(stderr, "ERROR: allocated blocks mismatch, is %" PRIu32
|
316 |
", should be %" PRIu32 "\n", |
317 |
blocks_allocated, s->header.blocks_allocated); |
318 |
res->corruptions++; |
319 |
} |
320 |
|
321 |
g_free(bmap); |
322 |
|
323 |
return 0; |
324 |
} |
325 |
|
326 |
static int vdi_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
327 |
{ |
328 |
/* TODO: vdi_get_info would be needed for machine snapshots.
|
329 |
vm_state_offset is still missing. */
|
330 |
BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
331 |
logout("\n");
|
332 |
bdi->cluster_size = s->block_size; |
333 |
bdi->vm_state_offset = 0;
|
334 |
return 0; |
335 |
} |
336 |
|
337 |
static int vdi_make_empty(BlockDriverState *bs) |
338 |
{ |
339 |
/* TODO: missing code. */
|
340 |
logout("\n");
|
341 |
/* The return value for missing code must be 0, see block.c. */
|
342 |
return 0; |
343 |
} |
344 |
|
345 |
static int vdi_probe(const uint8_t *buf, int buf_size, const char *filename) |
346 |
{ |
347 |
const VdiHeader *header = (const VdiHeader *)buf; |
348 |
int result = 0; |
349 |
|
350 |
logout("\n");
|
351 |
|
352 |
if (buf_size < sizeof(*header)) { |
353 |
/* Header too small, no VDI. */
|
354 |
} else if (le32_to_cpu(header->signature) == VDI_SIGNATURE) { |
355 |
result = 100;
|
356 |
} |
357 |
|
358 |
if (result == 0) { |
359 |
logout("no vdi image\n");
|
360 |
} else {
|
361 |
logout("%s", header->text);
|
362 |
} |
363 |
|
364 |
return result;
|
365 |
} |
366 |
|
367 |
static int vdi_open(BlockDriverState *bs, int flags) |
368 |
{ |
369 |
BDRVVdiState *s = bs->opaque; |
370 |
VdiHeader header; |
371 |
size_t bmap_size; |
372 |
|
373 |
logout("\n");
|
374 |
|
375 |
if (bdrv_read(bs->file, 0, (uint8_t *)&header, 1) < 0) { |
376 |
goto fail;
|
377 |
} |
378 |
|
379 |
vdi_header_to_cpu(&header); |
380 |
#if defined(CONFIG_VDI_DEBUG)
|
381 |
vdi_header_print(&header); |
382 |
#endif
|
383 |
|
384 |
if (header.disk_size % SECTOR_SIZE != 0) { |
385 |
/* 'VBoxManage convertfromraw' can create images with odd disk sizes.
|
386 |
We accept them but round the disk size to the next multiple of
|
387 |
SECTOR_SIZE. */
|
388 |
logout("odd disk size %" PRIu64 " B, round up\n", header.disk_size); |
389 |
header.disk_size += SECTOR_SIZE - 1;
|
390 |
header.disk_size &= ~(SECTOR_SIZE - 1);
|
391 |
} |
392 |
|
393 |
if (header.version != VDI_VERSION_1_1) {
|
394 |
logout("unsupported version %u.%u\n",
|
395 |
header.version >> 16, header.version & 0xffff); |
396 |
goto fail;
|
397 |
} else if (header.offset_bmap % SECTOR_SIZE != 0) { |
398 |
/* We only support block maps which start on a sector boundary. */
|
399 |
logout("unsupported block map offset 0x%x B\n", header.offset_bmap);
|
400 |
goto fail;
|
401 |
} else if (header.offset_data % SECTOR_SIZE != 0) { |
402 |
/* We only support data blocks which start on a sector boundary. */
|
403 |
logout("unsupported data offset 0x%x B\n", header.offset_data);
|
404 |
goto fail;
|
405 |
} else if (header.sector_size != SECTOR_SIZE) { |
406 |
logout("unsupported sector size %u B\n", header.sector_size);
|
407 |
goto fail;
|
408 |
} else if (header.block_size != 1 * MiB) { |
409 |
logout("unsupported block size %u B\n", header.block_size);
|
410 |
goto fail;
|
411 |
} else if (header.disk_size > |
412 |
(uint64_t)header.blocks_in_image * header.block_size) { |
413 |
logout("unsupported disk size %" PRIu64 " B\n", header.disk_size); |
414 |
goto fail;
|
415 |
} else if (!uuid_is_null(header.uuid_link)) { |
416 |
logout("link uuid != 0, unsupported\n");
|
417 |
goto fail;
|
418 |
} else if (!uuid_is_null(header.uuid_parent)) { |
419 |
logout("parent uuid != 0, unsupported\n");
|
420 |
goto fail;
|
421 |
} |
422 |
|
423 |
bs->total_sectors = header.disk_size / SECTOR_SIZE; |
424 |
|
425 |
s->block_size = header.block_size; |
426 |
s->block_sectors = header.block_size / SECTOR_SIZE; |
427 |
s->bmap_sector = header.offset_bmap / SECTOR_SIZE; |
428 |
s->header = header; |
429 |
|
430 |
bmap_size = header.blocks_in_image * sizeof(uint32_t);
|
431 |
bmap_size = (bmap_size + SECTOR_SIZE - 1) / SECTOR_SIZE;
|
432 |
if (bmap_size > 0) { |
433 |
s->bmap = g_malloc(bmap_size * SECTOR_SIZE); |
434 |
} |
435 |
if (bdrv_read(bs->file, s->bmap_sector, (uint8_t *)s->bmap, bmap_size) < 0) { |
436 |
goto fail_free_bmap;
|
437 |
} |
438 |
|
439 |
/* Disable migration when vdi images are used */
|
440 |
error_set(&s->migration_blocker, |
441 |
QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED, |
442 |
"vdi", bs->device_name, "live migration"); |
443 |
migrate_add_blocker(s->migration_blocker); |
444 |
|
445 |
return 0; |
446 |
|
447 |
fail_free_bmap:
|
448 |
g_free(s->bmap); |
449 |
|
450 |
fail:
|
451 |
return -1; |
452 |
} |
453 |
|
454 |
static int vdi_reopen_prepare(BDRVReopenState *state, |
455 |
BlockReopenQueue *queue, Error **errp) |
456 |
{ |
457 |
return 0; |
458 |
} |
459 |
|
460 |
static int coroutine_fn vdi_co_is_allocated(BlockDriverState *bs, |
461 |
int64_t sector_num, int nb_sectors, int *pnum) |
462 |
{ |
463 |
/* TODO: Check for too large sector_num (in bdrv_is_allocated or here). */
|
464 |
BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
465 |
size_t bmap_index = sector_num / s->block_sectors; |
466 |
size_t sector_in_block = sector_num % s->block_sectors; |
467 |
int n_sectors = s->block_sectors - sector_in_block;
|
468 |
uint32_t bmap_entry = le32_to_cpu(s->bmap[bmap_index]); |
469 |
logout("%p, %" PRId64 ", %d, %p\n", bs, sector_num, nb_sectors, pnum); |
470 |
if (n_sectors > nb_sectors) {
|
471 |
n_sectors = nb_sectors; |
472 |
} |
473 |
*pnum = n_sectors; |
474 |
return VDI_IS_ALLOCATED(bmap_entry);
|
475 |
} |
476 |
|
477 |
static int vdi_co_read(BlockDriverState *bs, |
478 |
int64_t sector_num, uint8_t *buf, int nb_sectors)
|
479 |
{ |
480 |
BDRVVdiState *s = bs->opaque; |
481 |
uint32_t bmap_entry; |
482 |
uint32_t block_index; |
483 |
uint32_t sector_in_block; |
484 |
uint32_t n_sectors; |
485 |
int ret = 0; |
486 |
|
487 |
logout("\n");
|
488 |
|
489 |
while (ret >= 0 && nb_sectors > 0) { |
490 |
block_index = sector_num / s->block_sectors; |
491 |
sector_in_block = sector_num % s->block_sectors; |
492 |
n_sectors = s->block_sectors - sector_in_block; |
493 |
if (n_sectors > nb_sectors) {
|
494 |
n_sectors = nb_sectors; |
495 |
} |
496 |
|
497 |
logout("will read %u sectors starting at sector %" PRIu64 "\n", |
498 |
n_sectors, sector_num); |
499 |
|
500 |
/* prepare next AIO request */
|
501 |
bmap_entry = le32_to_cpu(s->bmap[block_index]); |
502 |
if (!VDI_IS_ALLOCATED(bmap_entry)) {
|
503 |
/* Block not allocated, return zeros, no need to wait. */
|
504 |
memset(buf, 0, n_sectors * SECTOR_SIZE);
|
505 |
ret = 0;
|
506 |
} else {
|
507 |
uint64_t offset = s->header.offset_data / SECTOR_SIZE + |
508 |
(uint64_t)bmap_entry * s->block_sectors + |
509 |
sector_in_block; |
510 |
ret = bdrv_read(bs->file, offset, buf, n_sectors); |
511 |
} |
512 |
logout("%u sectors read\n", n_sectors);
|
513 |
|
514 |
nb_sectors -= n_sectors; |
515 |
sector_num += n_sectors; |
516 |
buf += n_sectors * SECTOR_SIZE; |
517 |
} |
518 |
|
519 |
return ret;
|
520 |
} |
521 |
|
522 |
static int vdi_co_write(BlockDriverState *bs, |
523 |
int64_t sector_num, const uint8_t *buf, int nb_sectors) |
524 |
{ |
525 |
BDRVVdiState *s = bs->opaque; |
526 |
uint32_t bmap_entry; |
527 |
uint32_t block_index; |
528 |
uint32_t sector_in_block; |
529 |
uint32_t n_sectors; |
530 |
uint32_t bmap_first = VDI_UNALLOCATED; |
531 |
uint32_t bmap_last = VDI_UNALLOCATED; |
532 |
uint8_t *block = NULL;
|
533 |
int ret = 0; |
534 |
|
535 |
logout("\n");
|
536 |
|
537 |
while (ret >= 0 && nb_sectors > 0) { |
538 |
block_index = sector_num / s->block_sectors; |
539 |
sector_in_block = sector_num % s->block_sectors; |
540 |
n_sectors = s->block_sectors - sector_in_block; |
541 |
if (n_sectors > nb_sectors) {
|
542 |
n_sectors = nb_sectors; |
543 |
} |
544 |
|
545 |
logout("will write %u sectors starting at sector %" PRIu64 "\n", |
546 |
n_sectors, sector_num); |
547 |
|
548 |
/* prepare next AIO request */
|
549 |
bmap_entry = le32_to_cpu(s->bmap[block_index]); |
550 |
if (!VDI_IS_ALLOCATED(bmap_entry)) {
|
551 |
/* Allocate new block and write to it. */
|
552 |
uint64_t offset; |
553 |
bmap_entry = s->header.blocks_allocated; |
554 |
s->bmap[block_index] = cpu_to_le32(bmap_entry); |
555 |
s->header.blocks_allocated++; |
556 |
offset = s->header.offset_data / SECTOR_SIZE + |
557 |
(uint64_t)bmap_entry * s->block_sectors; |
558 |
if (block == NULL) { |
559 |
block = g_malloc(s->block_size); |
560 |
bmap_first = block_index; |
561 |
} |
562 |
bmap_last = block_index; |
563 |
/* Copy data to be written to new block and zero unused parts. */
|
564 |
memset(block, 0, sector_in_block * SECTOR_SIZE);
|
565 |
memcpy(block + sector_in_block * SECTOR_SIZE, |
566 |
buf, n_sectors * SECTOR_SIZE); |
567 |
memset(block + (sector_in_block + n_sectors) * SECTOR_SIZE, 0,
|
568 |
(s->block_sectors - n_sectors - sector_in_block) * SECTOR_SIZE); |
569 |
ret = bdrv_write(bs->file, offset, block, s->block_sectors); |
570 |
} else {
|
571 |
uint64_t offset = s->header.offset_data / SECTOR_SIZE + |
572 |
(uint64_t)bmap_entry * s->block_sectors + |
573 |
sector_in_block; |
574 |
ret = bdrv_write(bs->file, offset, buf, n_sectors); |
575 |
} |
576 |
|
577 |
nb_sectors -= n_sectors; |
578 |
sector_num += n_sectors; |
579 |
buf += n_sectors * SECTOR_SIZE; |
580 |
|
581 |
logout("%u sectors written\n", n_sectors);
|
582 |
} |
583 |
|
584 |
logout("finished data write\n");
|
585 |
if (ret < 0) { |
586 |
return ret;
|
587 |
} |
588 |
|
589 |
if (block) {
|
590 |
/* One or more new blocks were allocated. */
|
591 |
VdiHeader *header = (VdiHeader *) block; |
592 |
uint8_t *base; |
593 |
uint64_t offset; |
594 |
|
595 |
logout("now writing modified header\n");
|
596 |
assert(VDI_IS_ALLOCATED(bmap_first)); |
597 |
*header = s->header; |
598 |
vdi_header_to_le(header); |
599 |
ret = bdrv_write(bs->file, 0, block, 1); |
600 |
g_free(block); |
601 |
block = NULL;
|
602 |
|
603 |
if (ret < 0) { |
604 |
return ret;
|
605 |
} |
606 |
|
607 |
logout("now writing modified block map entry %u...%u\n",
|
608 |
bmap_first, bmap_last); |
609 |
/* Write modified sectors from block map. */
|
610 |
bmap_first /= (SECTOR_SIZE / sizeof(uint32_t));
|
611 |
bmap_last /= (SECTOR_SIZE / sizeof(uint32_t));
|
612 |
n_sectors = bmap_last - bmap_first + 1;
|
613 |
offset = s->bmap_sector + bmap_first; |
614 |
base = ((uint8_t *)&s->bmap[0]) + bmap_first * SECTOR_SIZE;
|
615 |
logout("will write %u block map sectors starting from entry %u\n",
|
616 |
n_sectors, bmap_first); |
617 |
ret = bdrv_write(bs->file, offset, base, n_sectors); |
618 |
} |
619 |
|
620 |
return ret;
|
621 |
} |
622 |
|
623 |
static int vdi_create(const char *filename, QEMUOptionParameter *options) |
624 |
{ |
625 |
int fd;
|
626 |
int result = 0; |
627 |
uint64_t bytes = 0;
|
628 |
uint32_t blocks; |
629 |
size_t block_size = DEFAULT_CLUSTER_SIZE; |
630 |
uint32_t image_type = VDI_TYPE_DYNAMIC; |
631 |
VdiHeader header; |
632 |
size_t i; |
633 |
size_t bmap_size; |
634 |
|
635 |
logout("\n");
|
636 |
|
637 |
/* Read out options. */
|
638 |
while (options && options->name) {
|
639 |
if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
|
640 |
bytes = options->value.n; |
641 |
#if defined(CONFIG_VDI_BLOCK_SIZE)
|
642 |
} else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) { |
643 |
if (options->value.n) {
|
644 |
/* TODO: Additional checks (SECTOR_SIZE * 2^n, ...). */
|
645 |
block_size = options->value.n; |
646 |
} |
647 |
#endif
|
648 |
#if defined(CONFIG_VDI_STATIC_IMAGE)
|
649 |
} else if (!strcmp(options->name, BLOCK_OPT_STATIC)) { |
650 |
if (options->value.n) {
|
651 |
image_type = VDI_TYPE_STATIC; |
652 |
} |
653 |
#endif
|
654 |
} |
655 |
options++; |
656 |
} |
657 |
|
658 |
fd = qemu_open(filename, |
659 |
O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, |
660 |
0644);
|
661 |
if (fd < 0) { |
662 |
return -errno;
|
663 |
} |
664 |
|
665 |
/* We need enough blocks to store the given disk size,
|
666 |
so always round up. */
|
667 |
blocks = (bytes + block_size - 1) / block_size;
|
668 |
|
669 |
bmap_size = blocks * sizeof(uint32_t);
|
670 |
bmap_size = ((bmap_size + SECTOR_SIZE - 1) & ~(SECTOR_SIZE -1)); |
671 |
|
672 |
memset(&header, 0, sizeof(header)); |
673 |
pstrcpy(header.text, sizeof(header.text), VDI_TEXT);
|
674 |
header.signature = VDI_SIGNATURE; |
675 |
header.version = VDI_VERSION_1_1; |
676 |
header.header_size = 0x180;
|
677 |
header.image_type = image_type; |
678 |
header.offset_bmap = 0x200;
|
679 |
header.offset_data = 0x200 + bmap_size;
|
680 |
header.sector_size = SECTOR_SIZE; |
681 |
header.disk_size = bytes; |
682 |
header.block_size = block_size; |
683 |
header.blocks_in_image = blocks; |
684 |
if (image_type == VDI_TYPE_STATIC) {
|
685 |
header.blocks_allocated = blocks; |
686 |
} |
687 |
uuid_generate(header.uuid_image); |
688 |
uuid_generate(header.uuid_last_snap); |
689 |
/* There is no need to set header.uuid_link or header.uuid_parent here. */
|
690 |
#if defined(CONFIG_VDI_DEBUG)
|
691 |
vdi_header_print(&header); |
692 |
#endif
|
693 |
vdi_header_to_le(&header); |
694 |
if (write(fd, &header, sizeof(header)) < 0) { |
695 |
result = -errno; |
696 |
} |
697 |
|
698 |
if (bmap_size > 0) { |
699 |
uint32_t *bmap = g_malloc0(bmap_size); |
700 |
for (i = 0; i < blocks; i++) { |
701 |
if (image_type == VDI_TYPE_STATIC) {
|
702 |
bmap[i] = i; |
703 |
} else {
|
704 |
bmap[i] = VDI_UNALLOCATED; |
705 |
} |
706 |
} |
707 |
if (write(fd, bmap, bmap_size) < 0) { |
708 |
result = -errno; |
709 |
} |
710 |
g_free(bmap); |
711 |
} |
712 |
|
713 |
if (image_type == VDI_TYPE_STATIC) {
|
714 |
if (ftruncate(fd, sizeof(header) + bmap_size + blocks * block_size)) { |
715 |
result = -errno; |
716 |
} |
717 |
} |
718 |
|
719 |
if (close(fd) < 0) { |
720 |
result = -errno; |
721 |
} |
722 |
|
723 |
return result;
|
724 |
} |
725 |
|
726 |
static void vdi_close(BlockDriverState *bs) |
727 |
{ |
728 |
BDRVVdiState *s = bs->opaque; |
729 |
|
730 |
g_free(s->bmap); |
731 |
|
732 |
migrate_del_blocker(s->migration_blocker); |
733 |
error_free(s->migration_blocker); |
734 |
} |
735 |
|
736 |
static QEMUOptionParameter vdi_create_options[] = {
|
737 |
{ |
738 |
.name = BLOCK_OPT_SIZE, |
739 |
.type = OPT_SIZE, |
740 |
.help = "Virtual disk size"
|
741 |
}, |
742 |
#if defined(CONFIG_VDI_BLOCK_SIZE)
|
743 |
{ |
744 |
.name = BLOCK_OPT_CLUSTER_SIZE, |
745 |
.type = OPT_SIZE, |
746 |
.help = "VDI cluster (block) size",
|
747 |
.value = { .n = DEFAULT_CLUSTER_SIZE }, |
748 |
}, |
749 |
#endif
|
750 |
#if defined(CONFIG_VDI_STATIC_IMAGE)
|
751 |
{ |
752 |
.name = BLOCK_OPT_STATIC, |
753 |
.type = OPT_FLAG, |
754 |
.help = "VDI static (pre-allocated) image"
|
755 |
}, |
756 |
#endif
|
757 |
/* TODO: An additional option to set UUID values might be useful. */
|
758 |
{ NULL }
|
759 |
}; |
760 |
|
761 |
static BlockDriver bdrv_vdi = {
|
762 |
.format_name = "vdi",
|
763 |
.instance_size = sizeof(BDRVVdiState),
|
764 |
.bdrv_probe = vdi_probe, |
765 |
.bdrv_open = vdi_open, |
766 |
.bdrv_close = vdi_close, |
767 |
.bdrv_reopen_prepare = vdi_reopen_prepare, |
768 |
.bdrv_create = vdi_create, |
769 |
.bdrv_co_is_allocated = vdi_co_is_allocated, |
770 |
.bdrv_make_empty = vdi_make_empty, |
771 |
|
772 |
.bdrv_read = vdi_co_read, |
773 |
#if defined(CONFIG_VDI_WRITE)
|
774 |
.bdrv_write = vdi_co_write, |
775 |
#endif
|
776 |
|
777 |
.bdrv_get_info = vdi_get_info, |
778 |
|
779 |
.create_options = vdi_create_options, |
780 |
.bdrv_check = vdi_check, |
781 |
}; |
782 |
|
783 |
static void bdrv_vdi_init(void) |
784 |
{ |
785 |
logout("\n");
|
786 |
bdrv_register(&bdrv_vdi); |
787 |
} |
788 |
|
789 |
block_init(bdrv_vdi_init); |