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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 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_int.h" |
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#include "module.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.h" /* UUID_FMT */ |
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typedef unsigned char uuid_t[16]; |
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void uuid_generate(uuid_t out);
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int uuid_is_null(const uuid_t uu); |
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void uuid_unparse(const uuid_t uu, char *out); |
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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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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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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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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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BlockDriverAIOCB common; |
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int64_t sector_num; |
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QEMUIOVector *qiov; |
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uint8_t *buf; |
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/* Total number of sectors. */
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int nb_sectors;
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/* Number of sectors for current AIO. */
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int n_sectors;
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/* New allocated block map entry. */
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uint32_t bmap_first; |
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uint32_t bmap_last; |
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/* Buffer for new allocated block. */
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void *block_buffer;
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void *orig_buf;
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bool is_write;
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int header_modified;
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BlockDriverAIOCB *hd_aiocb; |
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struct iovec hd_iov;
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QEMUIOVector hd_qiov; |
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QEMUBH *bh; |
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} VdiAIOCB; |
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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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} 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); |
264 |
uuid_convert(header->uuid_parent); |
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} |
266 |
|
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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", |
284 |
header->disk_size, header->disk_size / MiB); |
285 |
logout("block size 0x%04x\n", header->block_size);
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286 |
logout("block extra 0x%04x\n", header->block_extra);
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287 |
logout("blocks tot. 0x%04x\n", header->blocks_in_image);
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288 |
logout("blocks all. 0x%04x\n", header->blocks_allocated);
|
289 |
uuid_unparse(header->uuid_image, uuid); |
290 |
logout("uuid image %s\n", uuid);
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291 |
uuid_unparse(header->uuid_last_snap, uuid); |
292 |
logout("uuid snap %s\n", uuid);
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293 |
uuid_unparse(header->uuid_link, uuid); |
294 |
logout("uuid link %s\n", uuid);
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295 |
uuid_unparse(header->uuid_parent, uuid); |
296 |
logout("uuid parent %s\n", uuid);
|
297 |
} |
298 |
#endif
|
299 |
|
300 |
static int vdi_check(BlockDriverState *bs, BdrvCheckResult *res) |
301 |
{ |
302 |
/* TODO: additional checks possible. */
|
303 |
BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
304 |
uint32_t blocks_allocated = 0;
|
305 |
uint32_t block; |
306 |
uint32_t *bmap; |
307 |
logout("\n");
|
308 |
|
309 |
bmap = g_malloc(s->header.blocks_in_image * sizeof(uint32_t));
|
310 |
memset(bmap, 0xff, s->header.blocks_in_image * sizeof(uint32_t)); |
311 |
|
312 |
/* Check block map and value of blocks_allocated. */
|
313 |
for (block = 0; block < s->header.blocks_in_image; block++) { |
314 |
uint32_t bmap_entry = le32_to_cpu(s->bmap[block]); |
315 |
if (VDI_IS_ALLOCATED(bmap_entry)) {
|
316 |
if (bmap_entry < s->header.blocks_in_image) {
|
317 |
blocks_allocated++; |
318 |
if (!VDI_IS_ALLOCATED(bmap[bmap_entry])) {
|
319 |
bmap[bmap_entry] = bmap_entry; |
320 |
} else {
|
321 |
fprintf(stderr, "ERROR: block index %" PRIu32
|
322 |
" also used by %" PRIu32 "\n", bmap[bmap_entry], bmap_entry); |
323 |
res->corruptions++; |
324 |
} |
325 |
} else {
|
326 |
fprintf(stderr, "ERROR: block index %" PRIu32
|
327 |
" too large, is %" PRIu32 "\n", block, bmap_entry); |
328 |
res->corruptions++; |
329 |
} |
330 |
} |
331 |
} |
332 |
if (blocks_allocated != s->header.blocks_allocated) {
|
333 |
fprintf(stderr, "ERROR: allocated blocks mismatch, is %" PRIu32
|
334 |
", should be %" PRIu32 "\n", |
335 |
blocks_allocated, s->header.blocks_allocated); |
336 |
res->corruptions++; |
337 |
} |
338 |
|
339 |
g_free(bmap); |
340 |
|
341 |
return 0; |
342 |
} |
343 |
|
344 |
static int vdi_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
345 |
{ |
346 |
/* TODO: vdi_get_info would be needed for machine snapshots.
|
347 |
vm_state_offset is still missing. */
|
348 |
BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
349 |
logout("\n");
|
350 |
bdi->cluster_size = s->block_size; |
351 |
bdi->vm_state_offset = 0;
|
352 |
return 0; |
353 |
} |
354 |
|
355 |
static int vdi_make_empty(BlockDriverState *bs) |
356 |
{ |
357 |
/* TODO: missing code. */
|
358 |
logout("\n");
|
359 |
/* The return value for missing code must be 0, see block.c. */
|
360 |
return 0; |
361 |
} |
362 |
|
363 |
static int vdi_probe(const uint8_t *buf, int buf_size, const char *filename) |
364 |
{ |
365 |
const VdiHeader *header = (const VdiHeader *)buf; |
366 |
int result = 0; |
367 |
|
368 |
logout("\n");
|
369 |
|
370 |
if (buf_size < sizeof(*header)) { |
371 |
/* Header too small, no VDI. */
|
372 |
} else if (le32_to_cpu(header->signature) == VDI_SIGNATURE) { |
373 |
result = 100;
|
374 |
} |
375 |
|
376 |
if (result == 0) { |
377 |
logout("no vdi image\n");
|
378 |
} else {
|
379 |
logout("%s", header->text);
|
380 |
} |
381 |
|
382 |
return result;
|
383 |
} |
384 |
|
385 |
static int vdi_open(BlockDriverState *bs, int flags) |
386 |
{ |
387 |
BDRVVdiState *s = bs->opaque; |
388 |
VdiHeader header; |
389 |
size_t bmap_size; |
390 |
|
391 |
logout("\n");
|
392 |
|
393 |
if (bdrv_read(bs->file, 0, (uint8_t *)&header, 1) < 0) { |
394 |
goto fail;
|
395 |
} |
396 |
|
397 |
vdi_header_to_cpu(&header); |
398 |
#if defined(CONFIG_VDI_DEBUG)
|
399 |
vdi_header_print(&header); |
400 |
#endif
|
401 |
|
402 |
if (header.disk_size % SECTOR_SIZE != 0) { |
403 |
/* 'VBoxManage convertfromraw' can create images with odd disk sizes.
|
404 |
We accept them but round the disk size to the next multiple of
|
405 |
SECTOR_SIZE. */
|
406 |
logout("odd disk size %" PRIu64 " B, round up\n", header.disk_size); |
407 |
header.disk_size += SECTOR_SIZE - 1;
|
408 |
header.disk_size &= ~(SECTOR_SIZE - 1);
|
409 |
} |
410 |
|
411 |
if (header.version != VDI_VERSION_1_1) {
|
412 |
logout("unsupported version %u.%u\n",
|
413 |
header.version >> 16, header.version & 0xffff); |
414 |
goto fail;
|
415 |
} else if (header.offset_bmap % SECTOR_SIZE != 0) { |
416 |
/* We only support block maps which start on a sector boundary. */
|
417 |
logout("unsupported block map offset 0x%x B\n", header.offset_bmap);
|
418 |
goto fail;
|
419 |
} else if (header.offset_data % SECTOR_SIZE != 0) { |
420 |
/* We only support data blocks which start on a sector boundary. */
|
421 |
logout("unsupported data offset 0x%x B\n", header.offset_data);
|
422 |
goto fail;
|
423 |
} else if (header.sector_size != SECTOR_SIZE) { |
424 |
logout("unsupported sector size %u B\n", header.sector_size);
|
425 |
goto fail;
|
426 |
} else if (header.block_size != 1 * MiB) { |
427 |
logout("unsupported block size %u B\n", header.block_size);
|
428 |
goto fail;
|
429 |
} else if (header.disk_size > |
430 |
(uint64_t)header.blocks_in_image * header.block_size) { |
431 |
logout("unsupported disk size %" PRIu64 " B\n", header.disk_size); |
432 |
goto fail;
|
433 |
} else if (!uuid_is_null(header.uuid_link)) { |
434 |
logout("link uuid != 0, unsupported\n");
|
435 |
goto fail;
|
436 |
} else if (!uuid_is_null(header.uuid_parent)) { |
437 |
logout("parent uuid != 0, unsupported\n");
|
438 |
goto fail;
|
439 |
} |
440 |
|
441 |
bs->total_sectors = header.disk_size / SECTOR_SIZE; |
442 |
|
443 |
s->block_size = header.block_size; |
444 |
s->block_sectors = header.block_size / SECTOR_SIZE; |
445 |
s->bmap_sector = header.offset_bmap / SECTOR_SIZE; |
446 |
s->header = header; |
447 |
|
448 |
bmap_size = header.blocks_in_image * sizeof(uint32_t);
|
449 |
bmap_size = (bmap_size + SECTOR_SIZE - 1) / SECTOR_SIZE;
|
450 |
if (bmap_size > 0) { |
451 |
s->bmap = g_malloc(bmap_size * SECTOR_SIZE); |
452 |
} |
453 |
if (bdrv_read(bs->file, s->bmap_sector, (uint8_t *)s->bmap, bmap_size) < 0) { |
454 |
goto fail_free_bmap;
|
455 |
} |
456 |
|
457 |
return 0; |
458 |
|
459 |
fail_free_bmap:
|
460 |
g_free(s->bmap); |
461 |
|
462 |
fail:
|
463 |
return -1; |
464 |
} |
465 |
|
466 |
static int vdi_is_allocated(BlockDriverState *bs, int64_t sector_num, |
467 |
int nb_sectors, int *pnum) |
468 |
{ |
469 |
/* TODO: Check for too large sector_num (in bdrv_is_allocated or here). */
|
470 |
BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
471 |
size_t bmap_index = sector_num / s->block_sectors; |
472 |
size_t sector_in_block = sector_num % s->block_sectors; |
473 |
int n_sectors = s->block_sectors - sector_in_block;
|
474 |
uint32_t bmap_entry = le32_to_cpu(s->bmap[bmap_index]); |
475 |
logout("%p, %" PRId64 ", %d, %p\n", bs, sector_num, nb_sectors, pnum); |
476 |
if (n_sectors > nb_sectors) {
|
477 |
n_sectors = nb_sectors; |
478 |
} |
479 |
*pnum = n_sectors; |
480 |
return VDI_IS_ALLOCATED(bmap_entry);
|
481 |
} |
482 |
|
483 |
static void vdi_aio_cancel(BlockDriverAIOCB *blockacb) |
484 |
{ |
485 |
/* TODO: This code is untested. How can I get it executed? */
|
486 |
VdiAIOCB *acb = container_of(blockacb, VdiAIOCB, common); |
487 |
logout("\n");
|
488 |
if (acb->hd_aiocb) {
|
489 |
bdrv_aio_cancel(acb->hd_aiocb); |
490 |
} |
491 |
qemu_aio_release(acb); |
492 |
} |
493 |
|
494 |
static AIOPool vdi_aio_pool = {
|
495 |
.aiocb_size = sizeof(VdiAIOCB),
|
496 |
.cancel = vdi_aio_cancel, |
497 |
}; |
498 |
|
499 |
static VdiAIOCB *vdi_aio_setup(BlockDriverState *bs, int64_t sector_num,
|
500 |
QEMUIOVector *qiov, int nb_sectors,
|
501 |
BlockDriverCompletionFunc *cb, void *opaque, int is_write) |
502 |
{ |
503 |
VdiAIOCB *acb; |
504 |
|
505 |
logout("%p, %" PRId64 ", %p, %d, %p, %p, %d\n", |
506 |
bs, sector_num, qiov, nb_sectors, cb, opaque, is_write); |
507 |
|
508 |
acb = qemu_aio_get(&vdi_aio_pool, bs, cb, opaque); |
509 |
if (acb) {
|
510 |
acb->hd_aiocb = NULL;
|
511 |
acb->sector_num = sector_num; |
512 |
acb->qiov = qiov; |
513 |
acb->is_write = is_write; |
514 |
|
515 |
if (qiov->niov > 1) { |
516 |
acb->buf = qemu_blockalign(bs, qiov->size); |
517 |
acb->orig_buf = acb->buf; |
518 |
if (is_write) {
|
519 |
qemu_iovec_to_buffer(qiov, acb->buf); |
520 |
} |
521 |
} else {
|
522 |
acb->buf = (uint8_t *)qiov->iov->iov_base; |
523 |
} |
524 |
acb->nb_sectors = nb_sectors; |
525 |
acb->n_sectors = 0;
|
526 |
acb->bmap_first = VDI_UNALLOCATED; |
527 |
acb->bmap_last = VDI_UNALLOCATED; |
528 |
acb->block_buffer = NULL;
|
529 |
acb->header_modified = 0;
|
530 |
} |
531 |
return acb;
|
532 |
} |
533 |
|
534 |
static int vdi_schedule_bh(QEMUBHFunc *cb, VdiAIOCB *acb) |
535 |
{ |
536 |
logout("\n");
|
537 |
|
538 |
if (acb->bh) {
|
539 |
return -EIO;
|
540 |
} |
541 |
|
542 |
acb->bh = qemu_bh_new(cb, acb); |
543 |
if (!acb->bh) {
|
544 |
return -EIO;
|
545 |
} |
546 |
|
547 |
qemu_bh_schedule(acb->bh); |
548 |
|
549 |
return 0; |
550 |
} |
551 |
|
552 |
static void vdi_aio_read_cb(void *opaque, int ret); |
553 |
static void vdi_aio_write_cb(void *opaque, int ret); |
554 |
|
555 |
static void vdi_aio_rw_bh(void *opaque) |
556 |
{ |
557 |
VdiAIOCB *acb = opaque; |
558 |
logout("\n");
|
559 |
qemu_bh_delete(acb->bh); |
560 |
acb->bh = NULL;
|
561 |
|
562 |
if (acb->is_write) {
|
563 |
vdi_aio_write_cb(opaque, 0);
|
564 |
} else {
|
565 |
vdi_aio_read_cb(opaque, 0);
|
566 |
} |
567 |
} |
568 |
|
569 |
static void vdi_aio_read_cb(void *opaque, int ret) |
570 |
{ |
571 |
VdiAIOCB *acb = opaque; |
572 |
BlockDriverState *bs = acb->common.bs; |
573 |
BDRVVdiState *s = bs->opaque; |
574 |
uint32_t bmap_entry; |
575 |
uint32_t block_index; |
576 |
uint32_t sector_in_block; |
577 |
uint32_t n_sectors; |
578 |
|
579 |
logout("%u sectors read\n", acb->n_sectors);
|
580 |
|
581 |
acb->hd_aiocb = NULL;
|
582 |
|
583 |
if (ret < 0) { |
584 |
goto done;
|
585 |
} |
586 |
|
587 |
acb->nb_sectors -= acb->n_sectors; |
588 |
|
589 |
if (acb->nb_sectors == 0) { |
590 |
/* request completed */
|
591 |
ret = 0;
|
592 |
goto done;
|
593 |
} |
594 |
|
595 |
acb->sector_num += acb->n_sectors; |
596 |
acb->buf += acb->n_sectors * SECTOR_SIZE; |
597 |
|
598 |
block_index = acb->sector_num / s->block_sectors; |
599 |
sector_in_block = acb->sector_num % s->block_sectors; |
600 |
n_sectors = s->block_sectors - sector_in_block; |
601 |
if (n_sectors > acb->nb_sectors) {
|
602 |
n_sectors = acb->nb_sectors; |
603 |
} |
604 |
|
605 |
logout("will read %u sectors starting at sector %" PRIu64 "\n", |
606 |
n_sectors, acb->sector_num); |
607 |
|
608 |
/* prepare next AIO request */
|
609 |
acb->n_sectors = n_sectors; |
610 |
bmap_entry = le32_to_cpu(s->bmap[block_index]); |
611 |
if (!VDI_IS_ALLOCATED(bmap_entry)) {
|
612 |
/* Block not allocated, return zeros, no need to wait. */
|
613 |
memset(acb->buf, 0, n_sectors * SECTOR_SIZE);
|
614 |
ret = vdi_schedule_bh(vdi_aio_rw_bh, acb); |
615 |
if (ret < 0) { |
616 |
goto done;
|
617 |
} |
618 |
} else {
|
619 |
uint64_t offset = s->header.offset_data / SECTOR_SIZE + |
620 |
(uint64_t)bmap_entry * s->block_sectors + |
621 |
sector_in_block; |
622 |
acb->hd_iov.iov_base = (void *)acb->buf;
|
623 |
acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE; |
624 |
qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
|
625 |
acb->hd_aiocb = bdrv_aio_readv(bs->file, offset, &acb->hd_qiov, |
626 |
n_sectors, vdi_aio_read_cb, acb); |
627 |
if (acb->hd_aiocb == NULL) { |
628 |
ret = -EIO; |
629 |
goto done;
|
630 |
} |
631 |
} |
632 |
return;
|
633 |
done:
|
634 |
if (acb->qiov->niov > 1) { |
635 |
qemu_iovec_from_buffer(acb->qiov, acb->orig_buf, acb->qiov->size); |
636 |
qemu_vfree(acb->orig_buf); |
637 |
} |
638 |
acb->common.cb(acb->common.opaque, ret); |
639 |
qemu_aio_release(acb); |
640 |
} |
641 |
|
642 |
static BlockDriverAIOCB *vdi_aio_readv(BlockDriverState *bs,
|
643 |
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
|
644 |
BlockDriverCompletionFunc *cb, void *opaque)
|
645 |
{ |
646 |
VdiAIOCB *acb; |
647 |
int ret;
|
648 |
|
649 |
logout("\n");
|
650 |
acb = vdi_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
|
651 |
if (!acb) {
|
652 |
return NULL; |
653 |
} |
654 |
|
655 |
ret = vdi_schedule_bh(vdi_aio_rw_bh, acb); |
656 |
if (ret < 0) { |
657 |
if (acb->qiov->niov > 1) { |
658 |
qemu_vfree(acb->orig_buf); |
659 |
} |
660 |
qemu_aio_release(acb); |
661 |
return NULL; |
662 |
} |
663 |
|
664 |
return &acb->common;
|
665 |
} |
666 |
|
667 |
static void vdi_aio_write_cb(void *opaque, int ret) |
668 |
{ |
669 |
VdiAIOCB *acb = opaque; |
670 |
BlockDriverState *bs = acb->common.bs; |
671 |
BDRVVdiState *s = bs->opaque; |
672 |
uint32_t bmap_entry; |
673 |
uint32_t block_index; |
674 |
uint32_t sector_in_block; |
675 |
uint32_t n_sectors; |
676 |
|
677 |
acb->hd_aiocb = NULL;
|
678 |
|
679 |
if (ret < 0) { |
680 |
goto done;
|
681 |
} |
682 |
|
683 |
acb->nb_sectors -= acb->n_sectors; |
684 |
acb->sector_num += acb->n_sectors; |
685 |
acb->buf += acb->n_sectors * SECTOR_SIZE; |
686 |
|
687 |
if (acb->nb_sectors == 0) { |
688 |
logout("finished data write\n");
|
689 |
acb->n_sectors = 0;
|
690 |
if (acb->header_modified) {
|
691 |
VdiHeader *header = acb->block_buffer; |
692 |
logout("now writing modified header\n");
|
693 |
assert(VDI_IS_ALLOCATED(acb->bmap_first)); |
694 |
*header = s->header; |
695 |
vdi_header_to_le(header); |
696 |
acb->header_modified = 0;
|
697 |
acb->hd_iov.iov_base = acb->block_buffer; |
698 |
acb->hd_iov.iov_len = SECTOR_SIZE; |
699 |
qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
|
700 |
acb->hd_aiocb = bdrv_aio_writev(bs->file, 0, &acb->hd_qiov, 1, |
701 |
vdi_aio_write_cb, acb); |
702 |
if (acb->hd_aiocb == NULL) { |
703 |
ret = -EIO; |
704 |
goto done;
|
705 |
} |
706 |
return;
|
707 |
} else if (VDI_IS_ALLOCATED(acb->bmap_first)) { |
708 |
/* One or more new blocks were allocated. */
|
709 |
uint64_t offset; |
710 |
uint32_t bmap_first; |
711 |
uint32_t bmap_last; |
712 |
g_free(acb->block_buffer); |
713 |
acb->block_buffer = NULL;
|
714 |
bmap_first = acb->bmap_first; |
715 |
bmap_last = acb->bmap_last; |
716 |
logout("now writing modified block map entry %u...%u\n",
|
717 |
bmap_first, bmap_last); |
718 |
/* Write modified sectors from block map. */
|
719 |
bmap_first /= (SECTOR_SIZE / sizeof(uint32_t));
|
720 |
bmap_last /= (SECTOR_SIZE / sizeof(uint32_t));
|
721 |
n_sectors = bmap_last - bmap_first + 1;
|
722 |
offset = s->bmap_sector + bmap_first; |
723 |
acb->bmap_first = VDI_UNALLOCATED; |
724 |
acb->hd_iov.iov_base = (void *)((uint8_t *)&s->bmap[0] + |
725 |
bmap_first * SECTOR_SIZE); |
726 |
acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE; |
727 |
qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
|
728 |
logout("will write %u block map sectors starting from entry %u\n",
|
729 |
n_sectors, bmap_first); |
730 |
acb->hd_aiocb = bdrv_aio_writev(bs->file, offset, &acb->hd_qiov, |
731 |
n_sectors, vdi_aio_write_cb, acb); |
732 |
if (acb->hd_aiocb == NULL) { |
733 |
ret = -EIO; |
734 |
goto done;
|
735 |
} |
736 |
return;
|
737 |
} |
738 |
ret = 0;
|
739 |
goto done;
|
740 |
} |
741 |
|
742 |
logout("%u sectors written\n", acb->n_sectors);
|
743 |
|
744 |
block_index = acb->sector_num / s->block_sectors; |
745 |
sector_in_block = acb->sector_num % s->block_sectors; |
746 |
n_sectors = s->block_sectors - sector_in_block; |
747 |
if (n_sectors > acb->nb_sectors) {
|
748 |
n_sectors = acb->nb_sectors; |
749 |
} |
750 |
|
751 |
logout("will write %u sectors starting at sector %" PRIu64 "\n", |
752 |
n_sectors, acb->sector_num); |
753 |
|
754 |
/* prepare next AIO request */
|
755 |
acb->n_sectors = n_sectors; |
756 |
bmap_entry = le32_to_cpu(s->bmap[block_index]); |
757 |
if (!VDI_IS_ALLOCATED(bmap_entry)) {
|
758 |
/* Allocate new block and write to it. */
|
759 |
uint64_t offset; |
760 |
uint8_t *block; |
761 |
bmap_entry = s->header.blocks_allocated; |
762 |
s->bmap[block_index] = cpu_to_le32(bmap_entry); |
763 |
s->header.blocks_allocated++; |
764 |
offset = s->header.offset_data / SECTOR_SIZE + |
765 |
(uint64_t)bmap_entry * s->block_sectors; |
766 |
block = acb->block_buffer; |
767 |
if (block == NULL) { |
768 |
block = g_malloc0(s->block_size); |
769 |
acb->block_buffer = block; |
770 |
acb->bmap_first = block_index; |
771 |
assert(!acb->header_modified); |
772 |
acb->header_modified = 1;
|
773 |
} |
774 |
acb->bmap_last = block_index; |
775 |
memcpy(block + sector_in_block * SECTOR_SIZE, |
776 |
acb->buf, n_sectors * SECTOR_SIZE); |
777 |
acb->hd_iov.iov_base = (void *)block;
|
778 |
acb->hd_iov.iov_len = s->block_size; |
779 |
qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
|
780 |
acb->hd_aiocb = bdrv_aio_writev(bs->file, offset, |
781 |
&acb->hd_qiov, s->block_sectors, |
782 |
vdi_aio_write_cb, acb); |
783 |
if (acb->hd_aiocb == NULL) { |
784 |
ret = -EIO; |
785 |
goto done;
|
786 |
} |
787 |
} else {
|
788 |
uint64_t offset = s->header.offset_data / SECTOR_SIZE + |
789 |
(uint64_t)bmap_entry * s->block_sectors + |
790 |
sector_in_block; |
791 |
acb->hd_iov.iov_base = (void *)acb->buf;
|
792 |
acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE; |
793 |
qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
|
794 |
acb->hd_aiocb = bdrv_aio_writev(bs->file, offset, &acb->hd_qiov, |
795 |
n_sectors, vdi_aio_write_cb, acb); |
796 |
if (acb->hd_aiocb == NULL) { |
797 |
ret = -EIO; |
798 |
goto done;
|
799 |
} |
800 |
} |
801 |
|
802 |
return;
|
803 |
|
804 |
done:
|
805 |
if (acb->qiov->niov > 1) { |
806 |
qemu_vfree(acb->orig_buf); |
807 |
} |
808 |
acb->common.cb(acb->common.opaque, ret); |
809 |
qemu_aio_release(acb); |
810 |
} |
811 |
|
812 |
static BlockDriverAIOCB *vdi_aio_writev(BlockDriverState *bs,
|
813 |
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
|
814 |
BlockDriverCompletionFunc *cb, void *opaque)
|
815 |
{ |
816 |
VdiAIOCB *acb; |
817 |
int ret;
|
818 |
|
819 |
logout("\n");
|
820 |
acb = vdi_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
|
821 |
if (!acb) {
|
822 |
return NULL; |
823 |
} |
824 |
|
825 |
ret = vdi_schedule_bh(vdi_aio_rw_bh, acb); |
826 |
if (ret < 0) { |
827 |
if (acb->qiov->niov > 1) { |
828 |
qemu_vfree(acb->orig_buf); |
829 |
} |
830 |
qemu_aio_release(acb); |
831 |
return NULL; |
832 |
} |
833 |
|
834 |
return &acb->common;
|
835 |
} |
836 |
|
837 |
static int vdi_create(const char *filename, QEMUOptionParameter *options) |
838 |
{ |
839 |
int fd;
|
840 |
int result = 0; |
841 |
uint64_t bytes = 0;
|
842 |
uint32_t blocks; |
843 |
size_t block_size = DEFAULT_CLUSTER_SIZE; |
844 |
uint32_t image_type = VDI_TYPE_DYNAMIC; |
845 |
VdiHeader header; |
846 |
size_t i; |
847 |
size_t bmap_size; |
848 |
uint32_t *bmap; |
849 |
|
850 |
logout("\n");
|
851 |
|
852 |
/* Read out options. */
|
853 |
while (options && options->name) {
|
854 |
if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
|
855 |
bytes = options->value.n; |
856 |
#if defined(CONFIG_VDI_BLOCK_SIZE)
|
857 |
} else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) { |
858 |
if (options->value.n) {
|
859 |
/* TODO: Additional checks (SECTOR_SIZE * 2^n, ...). */
|
860 |
block_size = options->value.n; |
861 |
} |
862 |
#endif
|
863 |
#if defined(CONFIG_VDI_STATIC_IMAGE)
|
864 |
} else if (!strcmp(options->name, BLOCK_OPT_STATIC)) { |
865 |
if (options->value.n) {
|
866 |
image_type = VDI_TYPE_STATIC; |
867 |
} |
868 |
#endif
|
869 |
} |
870 |
options++; |
871 |
} |
872 |
|
873 |
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, |
874 |
0644);
|
875 |
if (fd < 0) { |
876 |
return -errno;
|
877 |
} |
878 |
|
879 |
/* We need enough blocks to store the given disk size,
|
880 |
so always round up. */
|
881 |
blocks = (bytes + block_size - 1) / block_size;
|
882 |
|
883 |
bmap_size = blocks * sizeof(uint32_t);
|
884 |
bmap_size = ((bmap_size + SECTOR_SIZE - 1) & ~(SECTOR_SIZE -1)); |
885 |
|
886 |
memset(&header, 0, sizeof(header)); |
887 |
pstrcpy(header.text, sizeof(header.text), VDI_TEXT);
|
888 |
header.signature = VDI_SIGNATURE; |
889 |
header.version = VDI_VERSION_1_1; |
890 |
header.header_size = 0x180;
|
891 |
header.image_type = image_type; |
892 |
header.offset_bmap = 0x200;
|
893 |
header.offset_data = 0x200 + bmap_size;
|
894 |
header.sector_size = SECTOR_SIZE; |
895 |
header.disk_size = bytes; |
896 |
header.block_size = block_size; |
897 |
header.blocks_in_image = blocks; |
898 |
if (image_type == VDI_TYPE_STATIC) {
|
899 |
header.blocks_allocated = blocks; |
900 |
} |
901 |
uuid_generate(header.uuid_image); |
902 |
uuid_generate(header.uuid_last_snap); |
903 |
/* There is no need to set header.uuid_link or header.uuid_parent here. */
|
904 |
#if defined(CONFIG_VDI_DEBUG)
|
905 |
vdi_header_print(&header); |
906 |
#endif
|
907 |
vdi_header_to_le(&header); |
908 |
if (write(fd, &header, sizeof(header)) < 0) { |
909 |
result = -errno; |
910 |
} |
911 |
|
912 |
bmap = NULL;
|
913 |
if (bmap_size > 0) { |
914 |
bmap = (uint32_t *)g_malloc0(bmap_size); |
915 |
} |
916 |
for (i = 0; i < blocks; i++) { |
917 |
if (image_type == VDI_TYPE_STATIC) {
|
918 |
bmap[i] = i; |
919 |
} else {
|
920 |
bmap[i] = VDI_UNALLOCATED; |
921 |
} |
922 |
} |
923 |
if (write(fd, bmap, bmap_size) < 0) { |
924 |
result = -errno; |
925 |
} |
926 |
g_free(bmap); |
927 |
if (image_type == VDI_TYPE_STATIC) {
|
928 |
if (ftruncate(fd, sizeof(header) + bmap_size + blocks * block_size)) { |
929 |
result = -errno; |
930 |
} |
931 |
} |
932 |
|
933 |
if (close(fd) < 0) { |
934 |
result = -errno; |
935 |
} |
936 |
|
937 |
return result;
|
938 |
} |
939 |
|
940 |
static void vdi_close(BlockDriverState *bs) |
941 |
{ |
942 |
} |
943 |
|
944 |
static coroutine_fn int vdi_co_flush(BlockDriverState *bs) |
945 |
{ |
946 |
logout("\n");
|
947 |
return bdrv_co_flush(bs->file);
|
948 |
} |
949 |
|
950 |
|
951 |
static QEMUOptionParameter vdi_create_options[] = {
|
952 |
{ |
953 |
.name = BLOCK_OPT_SIZE, |
954 |
.type = OPT_SIZE, |
955 |
.help = "Virtual disk size"
|
956 |
}, |
957 |
#if defined(CONFIG_VDI_BLOCK_SIZE)
|
958 |
{ |
959 |
.name = BLOCK_OPT_CLUSTER_SIZE, |
960 |
.type = OPT_SIZE, |
961 |
.help = "VDI cluster (block) size",
|
962 |
.value = { .n = DEFAULT_CLUSTER_SIZE }, |
963 |
}, |
964 |
#endif
|
965 |
#if defined(CONFIG_VDI_STATIC_IMAGE)
|
966 |
{ |
967 |
.name = BLOCK_OPT_STATIC, |
968 |
.type = OPT_FLAG, |
969 |
.help = "VDI static (pre-allocated) image"
|
970 |
}, |
971 |
#endif
|
972 |
/* TODO: An additional option to set UUID values might be useful. */
|
973 |
{ NULL }
|
974 |
}; |
975 |
|
976 |
static BlockDriver bdrv_vdi = {
|
977 |
.format_name = "vdi",
|
978 |
.instance_size = sizeof(BDRVVdiState),
|
979 |
.bdrv_probe = vdi_probe, |
980 |
.bdrv_open = vdi_open, |
981 |
.bdrv_close = vdi_close, |
982 |
.bdrv_create = vdi_create, |
983 |
.bdrv_co_flush = vdi_co_flush, |
984 |
.bdrv_is_allocated = vdi_is_allocated, |
985 |
.bdrv_make_empty = vdi_make_empty, |
986 |
|
987 |
.bdrv_aio_readv = vdi_aio_readv, |
988 |
#if defined(CONFIG_VDI_WRITE)
|
989 |
.bdrv_aio_writev = vdi_aio_writev, |
990 |
#endif
|
991 |
|
992 |
.bdrv_get_info = vdi_get_info, |
993 |
|
994 |
.create_options = vdi_create_options, |
995 |
.bdrv_check = vdi_check, |
996 |
}; |
997 |
|
998 |
static void bdrv_vdi_init(void) |
999 |
{ |
1000 |
logout("\n");
|
1001 |
bdrv_register(&bdrv_vdi); |
1002 |
} |
1003 |
|
1004 |
block_init(bdrv_vdi_init); |