/* * Block driver for Parallels disk image format * * Copyright (c) 2007 Alex Beregszaszi * Copyright (c) 2015 Denis V. Lunev * * This code was originally based on comparing different disk images created * by Parallels. Currently it is based on opened OpenVZ sources * available at * http://git.openvz.org/?p=ploop;a=summary * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #include "qemu/osdep.h" #include "qapi/error.h" #include "qemu-common.h" #include "block/block_int.h" #include "sysemu/block-backend.h" #include "qemu/module.h" #include "qemu/bswap.h" #include "qemu/bitmap.h" #include "qapi/util.h" /**************************************************************/ #define HEADER_MAGIC "WithoutFreeSpace" #define HEADER_MAGIC2 "WithouFreSpacExt" #define HEADER_VERSION 2 #define HEADER_INUSE_MAGIC (0x746F6E59) #define MAX_PARALLELS_IMAGE_FACTOR (1ull << 32) #define DEFAULT_CLUSTER_SIZE 1048576 /* 1 MiB */ // always little-endian typedef struct ParallelsHeader { char magic[16]; // "WithoutFreeSpace" uint32_t version; uint32_t heads; uint32_t cylinders; uint32_t tracks; uint32_t bat_entries; uint64_t nb_sectors; uint32_t inuse; uint32_t data_off; char padding[12]; } QEMU_PACKED ParallelsHeader; typedef enum ParallelsPreallocMode { PRL_PREALLOC_MODE_FALLOCATE = 0, PRL_PREALLOC_MODE_TRUNCATE = 1, PRL_PREALLOC_MODE__MAX = 2, } ParallelsPreallocMode; static const char *prealloc_mode_lookup[] = { "falloc", "truncate", NULL, }; typedef struct BDRVParallelsState { /** Locking is conservative, the lock protects * - image file extending (truncate, fallocate) * - any access to block allocation table */ CoMutex lock; ParallelsHeader *header; uint32_t header_size; bool header_unclean; unsigned long *bat_dirty_bmap; unsigned int bat_dirty_block; uint32_t *bat_bitmap; unsigned int bat_size; int64_t data_end; uint64_t prealloc_size; ParallelsPreallocMode prealloc_mode; unsigned int tracks; unsigned int off_multiplier; } BDRVParallelsState; #define PARALLELS_OPT_PREALLOC_MODE "prealloc-mode" #define PARALLELS_OPT_PREALLOC_SIZE "prealloc-size" static QemuOptsList parallels_runtime_opts = { .name = "parallels", .head = QTAILQ_HEAD_INITIALIZER(parallels_runtime_opts.head), .desc = { { .name = PARALLELS_OPT_PREALLOC_SIZE, .type = QEMU_OPT_SIZE, .help = "Preallocation size on image expansion", .def_value_str = "128M", }, { .name = PARALLELS_OPT_PREALLOC_MODE, .type = QEMU_OPT_STRING, .help = "Preallocation mode on image expansion " "(allowed values: falloc, truncate)", .def_value_str = "falloc", }, { /* end of list */ }, }, }; static int64_t bat2sect(BDRVParallelsState *s, uint32_t idx) { return (uint64_t)le32_to_cpu(s->bat_bitmap[idx]) * s->off_multiplier; } static uint32_t bat_entry_off(uint32_t idx) { return sizeof(ParallelsHeader) + sizeof(uint32_t) * idx; } static int64_t seek_to_sector(BDRVParallelsState *s, int64_t sector_num) { uint32_t index, offset; index = sector_num / s->tracks; offset = sector_num % s->tracks; /* not allocated */ if ((index >= s->bat_size) || (s->bat_bitmap[index] == 0)) { return -1; } return bat2sect(s, index) + offset; } static int cluster_remainder(BDRVParallelsState *s, int64_t sector_num, int nb_sectors) { int ret = s->tracks - sector_num % s->tracks; return MIN(nb_sectors, ret); } static int64_t block_status(BDRVParallelsState *s, int64_t sector_num, int nb_sectors, int *pnum) { int64_t start_off = -2, prev_end_off = -2; *pnum = 0; while (nb_sectors > 0 || start_off == -2) { int64_t offset = seek_to_sector(s, sector_num); int to_end; if (start_off == -2) { start_off = offset; prev_end_off = offset; } else if (offset != prev_end_off) { break; } to_end = cluster_remainder(s, sector_num, nb_sectors); nb_sectors -= to_end; sector_num += to_end; *pnum += to_end; if (offset > 0) { prev_end_off += to_end; } } return start_off; } static int64_t allocate_clusters(BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum) { BDRVParallelsState *s = bs->opaque; int64_t pos, space, idx, to_allocate, i; pos = block_status(s, sector_num, nb_sectors, pnum); if (pos > 0) { return pos; } idx = sector_num / s->tracks; to_allocate = DIV_ROUND_UP(sector_num + *pnum, s->tracks) - idx; /* This function is called only by parallels_co_writev(), which will never * pass a sector_num at or beyond the end of the image (because the block * layer never passes such a sector_num to that function). Therefore, idx * is always below s->bat_size. * block_status() will limit *pnum so that sector_num + *pnum will not * exceed the image end. Therefore, idx + to_allocate cannot exceed * s->bat_size. * Note that s->bat_size is an unsigned int, therefore idx + to_allocate * will always fit into a uint32_t. */ assert(idx < s->bat_size && idx + to_allocate <= s->bat_size); space = to_allocate * s->tracks; if (s->data_end + space > bdrv_getlength(bs->file->bs) >> BDRV_SECTOR_BITS) { int ret; space += s->prealloc_size; if (s->prealloc_mode == PRL_PREALLOC_MODE_FALLOCATE) { ret = bdrv_pwrite_zeroes(bs->file, s->data_end << BDRV_SECTOR_BITS, space << BDRV_SECTOR_BITS, 0); } else { ret = bdrv_truncate(bs->file, (s->data_end + space) << BDRV_SECTOR_BITS, PREALLOC_MODE_OFF, NULL); } if (ret < 0) { return ret; } } for (i = 0; i < to_allocate; i++) { s->bat_bitmap[idx + i] = cpu_to_le32(s->data_end / s->off_multiplier); s->data_end += s->tracks; bitmap_set(s->bat_dirty_bmap, bat_entry_off(idx + i) / s->bat_dirty_block, 1); } return bat2sect(s, idx) + sector_num % s->tracks; } static coroutine_fn int parallels_co_flush_to_os(BlockDriverState *bs) { BDRVParallelsState *s = bs->opaque; unsigned long size = DIV_ROUND_UP(s->header_size, s->bat_dirty_block); unsigned long bit; qemu_co_mutex_lock(&s->lock); bit = find_first_bit(s->bat_dirty_bmap, size); while (bit < size) { uint32_t off = bit * s->bat_dirty_block; uint32_t to_write = s->bat_dirty_block; int ret; if (off + to_write > s->header_size) { to_write = s->header_size - off; } ret = bdrv_pwrite(bs->file, off, (uint8_t *)s->header + off, to_write); if (ret < 0) { qemu_co_mutex_unlock(&s->lock); return ret; } bit = find_next_bit(s->bat_dirty_bmap, size, bit + 1); } bitmap_zero(s->bat_dirty_bmap, size); qemu_co_mutex_unlock(&s->lock); return 0; } static int64_t coroutine_fn parallels_co_get_block_status(BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum, BlockDriverState **file) { BDRVParallelsState *s = bs->opaque; int64_t offset; qemu_co_mutex_lock(&s->lock); offset = block_status(s, sector_num, nb_sectors, pnum); qemu_co_mutex_unlock(&s->lock); if (offset < 0) { return 0; } *file = bs->file->bs; return (offset << BDRV_SECTOR_BITS) | BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; } static coroutine_fn int parallels_co_writev(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) { BDRVParallelsState *s = bs->opaque; uint64_t bytes_done = 0; QEMUIOVector hd_qiov; int ret = 0; qemu_iovec_init(&hd_qiov, qiov->niov); while (nb_sectors > 0) { int64_t position; int n, nbytes; qemu_co_mutex_lock(&s->lock); position = allocate_clusters(bs, sector_num, nb_sectors, &n); qemu_co_mutex_unlock(&s->lock); if (position < 0) { ret = (int)position; break; } nbytes = n << BDRV_SECTOR_BITS; qemu_iovec_reset(&hd_qiov); qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes); ret = bdrv_co_writev(bs->file, position, n, &hd_qiov); if (ret < 0) { break; } nb_sectors -= n; sector_num += n; bytes_done += nbytes; } qemu_iovec_destroy(&hd_qiov); return ret; } static coroutine_fn int parallels_co_readv(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) { BDRVParallelsState *s = bs->opaque; uint64_t bytes_done = 0; QEMUIOVector hd_qiov; int ret = 0; qemu_iovec_init(&hd_qiov, qiov->niov); while (nb_sectors > 0) { int64_t position; int n, nbytes; qemu_co_mutex_lock(&s->lock); position = block_status(s, sector_num, nb_sectors, &n); qemu_co_mutex_unlock(&s->lock); nbytes = n << BDRV_SECTOR_BITS; if (position < 0) { qemu_iovec_memset(qiov, bytes_done, 0, nbytes); } else { qemu_iovec_reset(&hd_qiov); qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes); ret = bdrv_co_readv(bs->file, position, n, &hd_qiov); if (ret < 0) { break; } } nb_sectors -= n; sector_num += n; bytes_done += nbytes; } qemu_iovec_destroy(&hd_qiov); return ret; } static int parallels_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix) { BDRVParallelsState *s = bs->opaque; int64_t size, prev_off, high_off; int ret; uint32_t i; bool flush_bat = false; int cluster_size = s->tracks << BDRV_SECTOR_BITS; size = bdrv_getlength(bs->file->bs); if (size < 0) { res->check_errors++; return size; } if (s->header_unclean) { fprintf(stderr, "%s image was not closed correctly\n", fix & BDRV_FIX_ERRORS ? "Repairing" : "ERROR"); res->corruptions++; if (fix & BDRV_FIX_ERRORS) { /* parallels_close will do the job right */ res->corruptions_fixed++; s->header_unclean = false; } } res->bfi.total_clusters = s->bat_size; res->bfi.compressed_clusters = 0; /* compression is not supported */ high_off = 0; prev_off = 0; for (i = 0; i < s->bat_size; i++) { int64_t off = bat2sect(s, i) << BDRV_SECTOR_BITS; if (off == 0) { prev_off = 0; continue; } /* cluster outside the image */ if (off > size) { fprintf(stderr, "%s cluster %u is outside image\n", fix & BDRV_FIX_ERRORS ? "Repairing" : "ERROR", i); res->corruptions++; if (fix & BDRV_FIX_ERRORS) { prev_off = 0; s->bat_bitmap[i] = 0; res->corruptions_fixed++; flush_bat = true; continue; } } res->bfi.allocated_clusters++; if (off > high_off) { high_off = off; } if (prev_off != 0 && (prev_off + cluster_size) != off) { res->bfi.fragmented_clusters++; } prev_off = off; } if (flush_bat) { ret = bdrv_pwrite_sync(bs->file, 0, s->header, s->header_size); if (ret < 0) { res->check_errors++; return ret; } } res->image_end_offset = high_off + cluster_size; if (size > res->image_end_offset) { int64_t count; count = DIV_ROUND_UP(size - res->image_end_offset, cluster_size); fprintf(stderr, "%s space leaked at the end of the image %" PRId64 "\n", fix & BDRV_FIX_LEAKS ? "Repairing" : "ERROR", size - res->image_end_offset); res->leaks += count; if (fix & BDRV_FIX_LEAKS) { Error *local_err = NULL; ret = bdrv_truncate(bs->file, res->image_end_offset, PREALLOC_MODE_OFF, &local_err); if (ret < 0) { error_report_err(local_err); res->check_errors++; return ret; } res->leaks_fixed += count; } } return 0; } static int parallels_create(const char *filename, QemuOpts *opts, Error **errp) { int64_t total_size, cl_size; uint8_t tmp[BDRV_SECTOR_SIZE]; Error *local_err = NULL; BlockBackend *file; uint32_t bat_entries, bat_sectors; ParallelsHeader header; int ret; total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), BDRV_SECTOR_SIZE); cl_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE, DEFAULT_CLUSTER_SIZE), BDRV_SECTOR_SIZE); if (total_size >= MAX_PARALLELS_IMAGE_FACTOR * cl_size) { error_propagate(errp, local_err); return -E2BIG; } ret = bdrv_create_file(filename, opts, &local_err); if (ret < 0) { error_propagate(errp, local_err); return ret; } file = blk_new_open(filename, NULL, NULL, BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, &local_err); if (file == NULL) { error_propagate(errp, local_err); return -EIO; } blk_set_allow_write_beyond_eof(file, true); ret = blk_truncate(file, 0, errp); if (ret < 0) { goto exit; } bat_entries = DIV_ROUND_UP(total_size, cl_size); bat_sectors = DIV_ROUND_UP(bat_entry_off(bat_entries), cl_size); bat_sectors = (bat_sectors * cl_size) >> BDRV_SECTOR_BITS; memset(&header, 0, sizeof(header)); memcpy(header.magic, HEADER_MAGIC2, sizeof(header.magic)); header.version = cpu_to_le32(HEADER_VERSION); /* don't care much about geometry, it is not used on image level */ header.heads = cpu_to_le32(16); header.cylinders = cpu_to_le32(total_size / BDRV_SECTOR_SIZE / 16 / 32); header.tracks = cpu_to_le32(cl_size >> BDRV_SECTOR_BITS); header.bat_entries = cpu_to_le32(bat_entries); header.nb_sectors = cpu_to_le64(DIV_ROUND_UP(total_size, BDRV_SECTOR_SIZE)); header.data_off = cpu_to_le32(bat_sectors); /* write all the data */ memset(tmp, 0, sizeof(tmp)); memcpy(tmp, &header, sizeof(header)); ret = blk_pwrite(file, 0, tmp, BDRV_SECTOR_SIZE, 0); if (ret < 0) { goto exit; } ret = blk_pwrite_zeroes(file, BDRV_SECTOR_SIZE, (bat_sectors - 1) << BDRV_SECTOR_BITS, 0); if (ret < 0) { goto exit; } ret = 0; done: blk_unref(file); return ret; exit: error_setg_errno(errp, -ret, "Failed to create Parallels image"); goto done; } static int parallels_probe(const uint8_t *buf, int buf_size, const char *filename) { const ParallelsHeader *ph = (const void *)buf; if (buf_size < sizeof(ParallelsHeader)) { return 0; } if ((!memcmp(ph->magic, HEADER_MAGIC, 16) || !memcmp(ph->magic, HEADER_MAGIC2, 16)) && (le32_to_cpu(ph->version) == HEADER_VERSION)) { return 100; } return 0; } static int parallels_update_header(BlockDriverState *bs) { BDRVParallelsState *s = bs->opaque; unsigned size = MAX(bdrv_opt_mem_align(bs->file->bs), sizeof(ParallelsHeader)); if (size > s->header_size) { size = s->header_size; } return bdrv_pwrite_sync(bs->file, 0, s->header, size); } static int parallels_open(BlockDriverState *bs, QDict *options, int flags, Error **errp) { BDRVParallelsState *s = bs->opaque; ParallelsHeader ph; int ret, size, i; QemuOpts *opts = NULL; Error *local_err = NULL; char *buf; bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, false, errp); if (!bs->file) { return -EINVAL; } ret = bdrv_pread(bs->file, 0, &ph, sizeof(ph)); if (ret < 0) { goto fail; } bs->total_sectors = le64_to_cpu(ph.nb_sectors); if (le32_to_cpu(ph.version) != HEADER_VERSION) { goto fail_format; } if (!memcmp(ph.magic, HEADER_MAGIC, 16)) { s->off_multiplier = 1; bs->total_sectors = 0xffffffff & bs->total_sectors; } else if (!memcmp(ph.magic, HEADER_MAGIC2, 16)) { s->off_multiplier = le32_to_cpu(ph.tracks); } else { goto fail_format; } s->tracks = le32_to_cpu(ph.tracks); if (s->tracks == 0) { error_setg(errp, "Invalid image: Zero sectors per track"); ret = -EINVAL; goto fail; } if (s->tracks > INT32_MAX/513) { error_setg(errp, "Invalid image: Too big cluster"); ret = -EFBIG; goto fail; } s->bat_size = le32_to_cpu(ph.bat_entries); if (s->bat_size > INT_MAX / sizeof(uint32_t)) { error_setg(errp, "Catalog too large"); ret = -EFBIG; goto fail; } size = bat_entry_off(s->bat_size); s->header_size = ROUND_UP(size, bdrv_opt_mem_align(bs->file->bs)); s->header = qemu_try_blockalign(bs->file->bs, s->header_size); if (s->header == NULL) { ret = -ENOMEM; goto fail; } s->data_end = le32_to_cpu(ph.data_off); if (s->data_end == 0) { s->data_end = ROUND_UP(bat_entry_off(s->bat_size), BDRV_SECTOR_SIZE); } if (s->data_end < s->header_size) { /* there is not enough unused space to fit to block align between BAT and actual data. We can't avoid read-modify-write... */ s->header_size = size; } ret = bdrv_pread(bs->file, 0, s->header, s->header_size); if (ret < 0) { goto fail; } s->bat_bitmap = (uint32_t *)(s->header + 1); for (i = 0; i < s->bat_size; i++) { int64_t off = bat2sect(s, i); if (off >= s->data_end) { s->data_end = off + s->tracks; } } if (le32_to_cpu(ph.inuse) == HEADER_INUSE_MAGIC) { /* Image was not closed correctly. The check is mandatory */ s->header_unclean = true; if ((flags & BDRV_O_RDWR) && !(flags & BDRV_O_CHECK)) { error_setg(errp, "parallels: Image was not closed correctly; " "cannot be opened read/write"); ret = -EACCES; goto fail; } } opts = qemu_opts_create(¶llels_runtime_opts, NULL, 0, &local_err); if (local_err != NULL) { goto fail_options; } qemu_opts_absorb_qdict(opts, options, &local_err); if (local_err != NULL) { goto fail_options; } s->prealloc_size = qemu_opt_get_size_del(opts, PARALLELS_OPT_PREALLOC_SIZE, 0); s->prealloc_size = MAX(s->tracks, s->prealloc_size >> BDRV_SECTOR_BITS); buf = qemu_opt_get_del(opts, PARALLELS_OPT_PREALLOC_MODE); s->prealloc_mode = qapi_enum_parse(prealloc_mode_lookup, buf, PRL_PREALLOC_MODE__MAX, PRL_PREALLOC_MODE_FALLOCATE, &local_err); g_free(buf); if (local_err != NULL) { goto fail_options; } if (!(flags & BDRV_O_RESIZE) || !bdrv_has_zero_init(bs->file->bs) || bdrv_truncate(bs->file, bdrv_getlength(bs->file->bs), PREALLOC_MODE_OFF, NULL) != 0) { s->prealloc_mode = PRL_PREALLOC_MODE_FALLOCATE; } if (flags & BDRV_O_RDWR) { s->header->inuse = cpu_to_le32(HEADER_INUSE_MAGIC); ret = parallels_update_header(bs); if (ret < 0) { goto fail; } } s->bat_dirty_block = 4 * getpagesize(); s->bat_dirty_bmap = bitmap_new(DIV_ROUND_UP(s->header_size, s->bat_dirty_block)); qemu_co_mutex_init(&s->lock); return 0; fail_format: error_setg(errp, "Image not in Parallels format"); ret = -EINVAL; fail: qemu_vfree(s->header); return ret; fail_options: error_propagate(errp, local_err); ret = -EINVAL; goto fail; } static void parallels_close(BlockDriverState *bs) { BDRVParallelsState *s = bs->opaque; if (bs->open_flags & BDRV_O_RDWR) { s->header->inuse = 0; parallels_update_header(bs); } if (bs->open_flags & BDRV_O_RDWR) { bdrv_truncate(bs->file, s->data_end << BDRV_SECTOR_BITS, PREALLOC_MODE_OFF, NULL); } g_free(s->bat_dirty_bmap); qemu_vfree(s->header); } static QemuOptsList parallels_create_opts = { .name = "parallels-create-opts", .head = QTAILQ_HEAD_INITIALIZER(parallels_create_opts.head), .desc = { { .name = BLOCK_OPT_SIZE, .type = QEMU_OPT_SIZE, .help = "Virtual disk size", }, { .name = BLOCK_OPT_CLUSTER_SIZE, .type = QEMU_OPT_SIZE, .help = "Parallels image cluster size", .def_value_str = stringify(DEFAULT_CLUSTER_SIZE), }, { /* end of list */ } } }; static BlockDriver bdrv_parallels = { .format_name = "parallels", .instance_size = sizeof(BDRVParallelsState), .bdrv_probe = parallels_probe, .bdrv_open = parallels_open, .bdrv_close = parallels_close, .bdrv_child_perm = bdrv_format_default_perms, .bdrv_co_get_block_status = parallels_co_get_block_status, .bdrv_has_zero_init = bdrv_has_zero_init_1, .bdrv_co_flush_to_os = parallels_co_flush_to_os, .bdrv_co_readv = parallels_co_readv, .bdrv_co_writev = parallels_co_writev, .bdrv_create = parallels_create, .bdrv_check = parallels_check, .create_opts = ¶llels_create_opts, }; static void bdrv_parallels_init(void) { bdrv_register(&bdrv_parallels); } block_init(bdrv_parallels_init);