diff options
Diffstat (limited to 'contrib/qemu/block/qcow2.c')
| -rw-r--r-- | contrib/qemu/block/qcow2.c | 1825 |
1 files changed, 0 insertions, 1825 deletions
diff --git a/contrib/qemu/block/qcow2.c b/contrib/qemu/block/qcow2.c deleted file mode 100644 index 0eceefe2cd9..00000000000 --- a/contrib/qemu/block/qcow2.c +++ /dev/null @@ -1,1825 +0,0 @@ -/* - * Block driver for the QCOW version 2 format - * - * Copyright (c) 2004-2006 Fabrice Bellard - * - * 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-common.h" -#include "block/block_int.h" -#include "qemu/module.h" -#include <zlib.h> -#include "qemu/aes.h" -#include "block/qcow2.h" -#include "qemu/error-report.h" -#include "qapi/qmp/qerror.h" -#include "qapi/qmp/qbool.h" -#include "trace.h" - -/* - Differences with QCOW: - - - Support for multiple incremental snapshots. - - Memory management by reference counts. - - Clusters which have a reference count of one have the bit - QCOW_OFLAG_COPIED to optimize write performance. - - Size of compressed clusters is stored in sectors to reduce bit usage - in the cluster offsets. - - Support for storing additional data (such as the VM state) in the - snapshots. - - If a backing store is used, the cluster size is not constrained - (could be backported to QCOW). - - L2 tables have always a size of one cluster. -*/ - - -typedef struct { - uint32_t magic; - uint32_t len; -} QCowExtension; - -#define QCOW2_EXT_MAGIC_END 0 -#define QCOW2_EXT_MAGIC_BACKING_FORMAT 0xE2792ACA -#define QCOW2_EXT_MAGIC_FEATURE_TABLE 0x6803f857 - -static int qcow2_probe(const uint8_t *buf, int buf_size, const char *filename) -{ - const QCowHeader *cow_header = (const void *)buf; - - if (buf_size >= sizeof(QCowHeader) && - be32_to_cpu(cow_header->magic) == QCOW_MAGIC && - be32_to_cpu(cow_header->version) >= 2) - return 100; - else - return 0; -} - - -/* - * read qcow2 extension and fill bs - * start reading from start_offset - * finish reading upon magic of value 0 or when end_offset reached - * unknown magic is skipped (future extension this version knows nothing about) - * return 0 upon success, non-0 otherwise - */ -static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset, - uint64_t end_offset, void **p_feature_table) -{ - BDRVQcowState *s = bs->opaque; - QCowExtension ext; - uint64_t offset; - int ret; - -#ifdef DEBUG_EXT - printf("qcow2_read_extensions: start=%ld end=%ld\n", start_offset, end_offset); -#endif - offset = start_offset; - while (offset < end_offset) { - -#ifdef DEBUG_EXT - /* Sanity check */ - if (offset > s->cluster_size) - printf("qcow2_read_extension: suspicious offset %lu\n", offset); - - printf("attempting to read extended header in offset %lu\n", offset); -#endif - - if (bdrv_pread(bs->file, offset, &ext, sizeof(ext)) != sizeof(ext)) { - fprintf(stderr, "qcow2_read_extension: ERROR: " - "pread fail from offset %" PRIu64 "\n", - offset); - return 1; - } - be32_to_cpus(&ext.magic); - be32_to_cpus(&ext.len); - offset += sizeof(ext); -#ifdef DEBUG_EXT - printf("ext.magic = 0x%x\n", ext.magic); -#endif - if (ext.len > end_offset - offset) { - error_report("Header extension too large"); - return -EINVAL; - } - - switch (ext.magic) { - case QCOW2_EXT_MAGIC_END: - return 0; - - case QCOW2_EXT_MAGIC_BACKING_FORMAT: - if (ext.len >= sizeof(bs->backing_format)) { - fprintf(stderr, "ERROR: ext_backing_format: len=%u too large" - " (>=%zu)\n", - ext.len, sizeof(bs->backing_format)); - return 2; - } - if (bdrv_pread(bs->file, offset , bs->backing_format, - ext.len) != ext.len) - return 3; - bs->backing_format[ext.len] = '\0'; -#ifdef DEBUG_EXT - printf("Qcow2: Got format extension %s\n", bs->backing_format); -#endif - break; - - case QCOW2_EXT_MAGIC_FEATURE_TABLE: - if (p_feature_table != NULL) { - void* feature_table = g_malloc0(ext.len + 2 * sizeof(Qcow2Feature)); - ret = bdrv_pread(bs->file, offset , feature_table, ext.len); - if (ret < 0) { - return ret; - } - - *p_feature_table = feature_table; - } - break; - - default: - /* unknown magic - save it in case we need to rewrite the header */ - { - Qcow2UnknownHeaderExtension *uext; - - uext = g_malloc0(sizeof(*uext) + ext.len); - uext->magic = ext.magic; - uext->len = ext.len; - QLIST_INSERT_HEAD(&s->unknown_header_ext, uext, next); - - ret = bdrv_pread(bs->file, offset , uext->data, uext->len); - if (ret < 0) { - return ret; - } - } - break; - } - - offset += ((ext.len + 7) & ~7); - } - - return 0; -} - -static void cleanup_unknown_header_ext(BlockDriverState *bs) -{ - BDRVQcowState *s = bs->opaque; - Qcow2UnknownHeaderExtension *uext, *next; - - QLIST_FOREACH_SAFE(uext, &s->unknown_header_ext, next, next) { - QLIST_REMOVE(uext, next); - g_free(uext); - } -} - -static void GCC_FMT_ATTR(2, 3) report_unsupported(BlockDriverState *bs, - const char *fmt, ...) -{ - char msg[64]; - va_list ap; - - va_start(ap, fmt); - vsnprintf(msg, sizeof(msg), fmt, ap); - va_end(ap); - - qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE, - bs->device_name, "qcow2", msg); -} - -static void report_unsupported_feature(BlockDriverState *bs, - Qcow2Feature *table, uint64_t mask) -{ - while (table && table->name[0] != '\0') { - if (table->type == QCOW2_FEAT_TYPE_INCOMPATIBLE) { - if (mask & (1 << table->bit)) { - report_unsupported(bs, "%.46s",table->name); - mask &= ~(1 << table->bit); - } - } - table++; - } - - if (mask) { - report_unsupported(bs, "Unknown incompatible feature: %" PRIx64, mask); - } -} - -/* - * Sets the dirty bit and flushes afterwards if necessary. - * - * The incompatible_features bit is only set if the image file header was - * updated successfully. Therefore it is not required to check the return - * value of this function. - */ -int qcow2_mark_dirty(BlockDriverState *bs) -{ - BDRVQcowState *s = bs->opaque; - uint64_t val; - int ret; - - assert(s->qcow_version >= 3); - - if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) { - return 0; /* already dirty */ - } - - val = cpu_to_be64(s->incompatible_features | QCOW2_INCOMPAT_DIRTY); - ret = bdrv_pwrite(bs->file, offsetof(QCowHeader, incompatible_features), - &val, sizeof(val)); - if (ret < 0) { - return ret; - } - ret = bdrv_flush(bs->file); - if (ret < 0) { - return ret; - } - - /* Only treat image as dirty if the header was updated successfully */ - s->incompatible_features |= QCOW2_INCOMPAT_DIRTY; - return 0; -} - -/* - * Clears the dirty bit and flushes before if necessary. Only call this - * function when there are no pending requests, it does not guard against - * concurrent requests dirtying the image. - */ -static int qcow2_mark_clean(BlockDriverState *bs) -{ - BDRVQcowState *s = bs->opaque; - - if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) { - int ret = bdrv_flush(bs); - if (ret < 0) { - return ret; - } - - s->incompatible_features &= ~QCOW2_INCOMPAT_DIRTY; - return qcow2_update_header(bs); - } - return 0; -} - -static int qcow2_check(BlockDriverState *bs, BdrvCheckResult *result, - BdrvCheckMode fix) -{ - int ret = qcow2_check_refcounts(bs, result, fix); - if (ret < 0) { - return ret; - } - - if (fix && result->check_errors == 0 && result->corruptions == 0) { - return qcow2_mark_clean(bs); - } - return ret; -} - -static QemuOptsList qcow2_runtime_opts = { - .name = "qcow2", - .head = QTAILQ_HEAD_INITIALIZER(qcow2_runtime_opts.head), - .desc = { - { - .name = "lazy_refcounts", - .type = QEMU_OPT_BOOL, - .help = "Postpone refcount updates", - }, - { - .name = QCOW2_OPT_DISCARD_REQUEST, - .type = QEMU_OPT_BOOL, - .help = "Pass guest discard requests to the layer below", - }, - { - .name = QCOW2_OPT_DISCARD_SNAPSHOT, - .type = QEMU_OPT_BOOL, - .help = "Generate discard requests when snapshot related space " - "is freed", - }, - { - .name = QCOW2_OPT_DISCARD_OTHER, - .type = QEMU_OPT_BOOL, - .help = "Generate discard requests when other clusters are freed", - }, - { /* end of list */ } - }, -}; - -static int qcow2_open(BlockDriverState *bs, QDict *options, int flags) -{ - BDRVQcowState *s = bs->opaque; - int len, i, ret = 0; - QCowHeader header; - QemuOpts *opts; - Error *local_err = NULL; - uint64_t ext_end; - uint64_t l1_vm_state_index; - - ret = bdrv_pread(bs->file, 0, &header, sizeof(header)); - if (ret < 0) { - goto fail; - } - be32_to_cpus(&header.magic); - be32_to_cpus(&header.version); - be64_to_cpus(&header.backing_file_offset); - be32_to_cpus(&header.backing_file_size); - be64_to_cpus(&header.size); - be32_to_cpus(&header.cluster_bits); - be32_to_cpus(&header.crypt_method); - be64_to_cpus(&header.l1_table_offset); - be32_to_cpus(&header.l1_size); - be64_to_cpus(&header.refcount_table_offset); - be32_to_cpus(&header.refcount_table_clusters); - be64_to_cpus(&header.snapshots_offset); - be32_to_cpus(&header.nb_snapshots); - - if (header.magic != QCOW_MAGIC) { - ret = -EMEDIUMTYPE; - goto fail; - } - if (header.version < 2 || header.version > 3) { - report_unsupported(bs, "QCOW version %d", header.version); - ret = -ENOTSUP; - goto fail; - } - - s->qcow_version = header.version; - - /* Initialise version 3 header fields */ - if (header.version == 2) { - header.incompatible_features = 0; - header.compatible_features = 0; - header.autoclear_features = 0; - header.refcount_order = 4; - header.header_length = 72; - } else { - be64_to_cpus(&header.incompatible_features); - be64_to_cpus(&header.compatible_features); - be64_to_cpus(&header.autoclear_features); - be32_to_cpus(&header.refcount_order); - be32_to_cpus(&header.header_length); - } - - if (header.header_length > sizeof(header)) { - s->unknown_header_fields_size = header.header_length - sizeof(header); - s->unknown_header_fields = g_malloc(s->unknown_header_fields_size); - ret = bdrv_pread(bs->file, sizeof(header), s->unknown_header_fields, - s->unknown_header_fields_size); - if (ret < 0) { - goto fail; - } - } - - if (header.backing_file_offset) { - ext_end = header.backing_file_offset; - } else { - ext_end = 1 << header.cluster_bits; - } - - /* Handle feature bits */ - s->incompatible_features = header.incompatible_features; - s->compatible_features = header.compatible_features; - s->autoclear_features = header.autoclear_features; - - if (s->incompatible_features & ~QCOW2_INCOMPAT_MASK) { - void *feature_table = NULL; - qcow2_read_extensions(bs, header.header_length, ext_end, - &feature_table); - report_unsupported_feature(bs, feature_table, - s->incompatible_features & - ~QCOW2_INCOMPAT_MASK); - ret = -ENOTSUP; - goto fail; - } - - /* Check support for various header values */ - if (header.refcount_order != 4) { - report_unsupported(bs, "%d bit reference counts", - 1 << header.refcount_order); - ret = -ENOTSUP; - goto fail; - } - - if (header.cluster_bits < MIN_CLUSTER_BITS || - header.cluster_bits > MAX_CLUSTER_BITS) { - ret = -EINVAL; - goto fail; - } - if (header.crypt_method > QCOW_CRYPT_AES) { - ret = -EINVAL; - goto fail; - } - s->crypt_method_header = header.crypt_method; - if (s->crypt_method_header) { - bs->encrypted = 1; - } - s->cluster_bits = header.cluster_bits; - s->cluster_size = 1 << s->cluster_bits; - s->cluster_sectors = 1 << (s->cluster_bits - 9); - s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */ - s->l2_size = 1 << s->l2_bits; - bs->total_sectors = header.size / 512; - s->csize_shift = (62 - (s->cluster_bits - 8)); - s->csize_mask = (1 << (s->cluster_bits - 8)) - 1; - s->cluster_offset_mask = (1LL << s->csize_shift) - 1; - s->refcount_table_offset = header.refcount_table_offset; - s->refcount_table_size = - header.refcount_table_clusters << (s->cluster_bits - 3); - - s->snapshots_offset = header.snapshots_offset; - s->nb_snapshots = header.nb_snapshots; - - /* read the level 1 table */ - s->l1_size = header.l1_size; - - l1_vm_state_index = size_to_l1(s, header.size); - if (l1_vm_state_index > INT_MAX) { - ret = -EFBIG; - goto fail; - } - s->l1_vm_state_index = l1_vm_state_index; - - /* the L1 table must contain at least enough entries to put - header.size bytes */ - if (s->l1_size < s->l1_vm_state_index) { - ret = -EINVAL; - goto fail; - } - s->l1_table_offset = header.l1_table_offset; - if (s->l1_size > 0) { - s->l1_table = g_malloc0( - align_offset(s->l1_size * sizeof(uint64_t), 512)); - ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table, - s->l1_size * sizeof(uint64_t)); - if (ret < 0) { - goto fail; - } - for(i = 0;i < s->l1_size; i++) { - be64_to_cpus(&s->l1_table[i]); - } - } - - /* alloc L2 table/refcount block cache */ - s->l2_table_cache = qcow2_cache_create(bs, L2_CACHE_SIZE); - s->refcount_block_cache = qcow2_cache_create(bs, REFCOUNT_CACHE_SIZE); - - s->cluster_cache = g_malloc(s->cluster_size); - /* one more sector for decompressed data alignment */ - s->cluster_data = qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size - + 512); - s->cluster_cache_offset = -1; - s->flags = flags; - - ret = qcow2_refcount_init(bs); - if (ret != 0) { - goto fail; - } - - QLIST_INIT(&s->cluster_allocs); - QTAILQ_INIT(&s->discards); - - /* read qcow2 extensions */ - if (qcow2_read_extensions(bs, header.header_length, ext_end, NULL)) { - ret = -EINVAL; - goto fail; - } - - /* read the backing file name */ - if (header.backing_file_offset != 0) { - len = header.backing_file_size; - if (len > 1023) { - len = 1023; - } - ret = bdrv_pread(bs->file, header.backing_file_offset, - bs->backing_file, len); - if (ret < 0) { - goto fail; - } - bs->backing_file[len] = '\0'; - } - - ret = qcow2_read_snapshots(bs); - if (ret < 0) { - goto fail; - } - - /* Clear unknown autoclear feature bits */ - if (!bs->read_only && s->autoclear_features != 0) { - s->autoclear_features = 0; - ret = qcow2_update_header(bs); - if (ret < 0) { - goto fail; - } - } - - /* Initialise locks */ - qemu_co_mutex_init(&s->lock); - - /* Repair image if dirty */ - if (!(flags & BDRV_O_CHECK) && !bs->read_only && - (s->incompatible_features & QCOW2_INCOMPAT_DIRTY)) { - BdrvCheckResult result = {0}; - - ret = qcow2_check(bs, &result, BDRV_FIX_ERRORS); - if (ret < 0) { - goto fail; - } - } - - /* Enable lazy_refcounts according to image and command line options */ - opts = qemu_opts_create_nofail(&qcow2_runtime_opts); - qemu_opts_absorb_qdict(opts, options, &local_err); - if (error_is_set(&local_err)) { - qerror_report_err(local_err); - error_free(local_err); - ret = -EINVAL; - goto fail; - } - - s->use_lazy_refcounts = qemu_opt_get_bool(opts, QCOW2_OPT_LAZY_REFCOUNTS, - (s->compatible_features & QCOW2_COMPAT_LAZY_REFCOUNTS)); - - s->discard_passthrough[QCOW2_DISCARD_NEVER] = false; - s->discard_passthrough[QCOW2_DISCARD_ALWAYS] = true; - s->discard_passthrough[QCOW2_DISCARD_REQUEST] = - qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_REQUEST, - flags & BDRV_O_UNMAP); - s->discard_passthrough[QCOW2_DISCARD_SNAPSHOT] = - qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_SNAPSHOT, true); - s->discard_passthrough[QCOW2_DISCARD_OTHER] = - qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_OTHER, false); - - qemu_opts_del(opts); - - if (s->use_lazy_refcounts && s->qcow_version < 3) { - qerror_report(ERROR_CLASS_GENERIC_ERROR, "Lazy refcounts require " - "a qcow2 image with at least qemu 1.1 compatibility level"); - ret = -EINVAL; - goto fail; - } - -#ifdef DEBUG_ALLOC - { - BdrvCheckResult result = {0}; - qcow2_check_refcounts(bs, &result, 0); - } -#endif - return ret; - - fail: - g_free(s->unknown_header_fields); - cleanup_unknown_header_ext(bs); - qcow2_free_snapshots(bs); - qcow2_refcount_close(bs); - g_free(s->l1_table); - if (s->l2_table_cache) { - qcow2_cache_destroy(bs, s->l2_table_cache); - } - g_free(s->cluster_cache); - qemu_vfree(s->cluster_data); - return ret; -} - -static int qcow2_set_key(BlockDriverState *bs, const char *key) -{ - BDRVQcowState *s = bs->opaque; - uint8_t keybuf[16]; - int len, i; - - memset(keybuf, 0, 16); - len = strlen(key); - if (len > 16) - len = 16; - /* XXX: we could compress the chars to 7 bits to increase - entropy */ - for(i = 0;i < len;i++) { - keybuf[i] = key[i]; - } - s->crypt_method = s->crypt_method_header; - - if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0) - return -1; - if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0) - return -1; -#if 0 - /* test */ - { - uint8_t in[16]; - uint8_t out[16]; - uint8_t tmp[16]; - for(i=0;i<16;i++) - in[i] = i; - AES_encrypt(in, tmp, &s->aes_encrypt_key); - AES_decrypt(tmp, out, &s->aes_decrypt_key); - for(i = 0; i < 16; i++) - printf(" %02x", tmp[i]); - printf("\n"); - for(i = 0; i < 16; i++) - printf(" %02x", out[i]); - printf("\n"); - } -#endif - return 0; -} - -/* We have nothing to do for QCOW2 reopen, stubs just return - * success */ -static int qcow2_reopen_prepare(BDRVReopenState *state, - BlockReopenQueue *queue, Error **errp) -{ - return 0; -} - -static int coroutine_fn qcow2_co_is_allocated(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, int *pnum) -{ - BDRVQcowState *s = bs->opaque; - uint64_t cluster_offset; - int ret; - - *pnum = nb_sectors; - /* FIXME We can get errors here, but the bdrv_co_is_allocated interface - * can't pass them on today */ - qemu_co_mutex_lock(&s->lock); - ret = qcow2_get_cluster_offset(bs, sector_num << 9, pnum, &cluster_offset); - qemu_co_mutex_unlock(&s->lock); - if (ret < 0) { - *pnum = 0; - } - - return (cluster_offset != 0) || (ret == QCOW2_CLUSTER_ZERO); -} - -/* handle reading after the end of the backing file */ -int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov, - int64_t sector_num, int nb_sectors) -{ - int n1; - if ((sector_num + nb_sectors) <= bs->total_sectors) - return nb_sectors; - if (sector_num >= bs->total_sectors) - n1 = 0; - else - n1 = bs->total_sectors - sector_num; - - qemu_iovec_memset(qiov, 512 * n1, 0, 512 * (nb_sectors - n1)); - - return n1; -} - -static coroutine_fn int qcow2_co_readv(BlockDriverState *bs, int64_t sector_num, - int remaining_sectors, QEMUIOVector *qiov) -{ - BDRVQcowState *s = bs->opaque; - int index_in_cluster, n1; - int ret; - int cur_nr_sectors; /* number of sectors in current iteration */ - uint64_t cluster_offset = 0; - uint64_t bytes_done = 0; - QEMUIOVector hd_qiov; - uint8_t *cluster_data = NULL; - - qemu_iovec_init(&hd_qiov, qiov->niov); - - qemu_co_mutex_lock(&s->lock); - - while (remaining_sectors != 0) { - - /* prepare next request */ - cur_nr_sectors = remaining_sectors; - if (s->crypt_method) { - cur_nr_sectors = MIN(cur_nr_sectors, - QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors); - } - - ret = qcow2_get_cluster_offset(bs, sector_num << 9, - &cur_nr_sectors, &cluster_offset); - if (ret < 0) { - goto fail; - } - - index_in_cluster = sector_num & (s->cluster_sectors - 1); - - qemu_iovec_reset(&hd_qiov); - qemu_iovec_concat(&hd_qiov, qiov, bytes_done, - cur_nr_sectors * 512); - - switch (ret) { - case QCOW2_CLUSTER_UNALLOCATED: - - if (bs->backing_hd) { - /* read from the base image */ - n1 = qcow2_backing_read1(bs->backing_hd, &hd_qiov, - sector_num, cur_nr_sectors); - if (n1 > 0) { - BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO); - qemu_co_mutex_unlock(&s->lock); - ret = bdrv_co_readv(bs->backing_hd, sector_num, - n1, &hd_qiov); - qemu_co_mutex_lock(&s->lock); - if (ret < 0) { - goto fail; - } - } - } else { - /* Note: in this case, no need to wait */ - qemu_iovec_memset(&hd_qiov, 0, 0, 512 * cur_nr_sectors); - } - break; - - case QCOW2_CLUSTER_ZERO: - qemu_iovec_memset(&hd_qiov, 0, 0, 512 * cur_nr_sectors); - break; - - case QCOW2_CLUSTER_COMPRESSED: - /* add AIO support for compressed blocks ? */ - ret = qcow2_decompress_cluster(bs, cluster_offset); - if (ret < 0) { - goto fail; - } - - qemu_iovec_from_buf(&hd_qiov, 0, - s->cluster_cache + index_in_cluster * 512, - 512 * cur_nr_sectors); - break; - - case QCOW2_CLUSTER_NORMAL: - if ((cluster_offset & 511) != 0) { - ret = -EIO; - goto fail; - } - - if (s->crypt_method) { - /* - * For encrypted images, read everything into a temporary - * contiguous buffer on which the AES functions can work. - */ - if (!cluster_data) { - cluster_data = - qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); - } - - assert(cur_nr_sectors <= - QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors); - qemu_iovec_reset(&hd_qiov); - qemu_iovec_add(&hd_qiov, cluster_data, - 512 * cur_nr_sectors); - } - - BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); - qemu_co_mutex_unlock(&s->lock); - ret = bdrv_co_readv(bs->file, - (cluster_offset >> 9) + index_in_cluster, - cur_nr_sectors, &hd_qiov); - qemu_co_mutex_lock(&s->lock); - if (ret < 0) { - goto fail; - } - if (s->crypt_method) { - qcow2_encrypt_sectors(s, sector_num, cluster_data, - cluster_data, cur_nr_sectors, 0, &s->aes_decrypt_key); - qemu_iovec_from_buf(qiov, bytes_done, - cluster_data, 512 * cur_nr_sectors); - } - break; - - default: - g_assert_not_reached(); - ret = -EIO; - goto fail; - } - - remaining_sectors -= cur_nr_sectors; - sector_num += cur_nr_sectors; - bytes_done += cur_nr_sectors * 512; - } - ret = 0; - -fail: - qemu_co_mutex_unlock(&s->lock); - - qemu_iovec_destroy(&hd_qiov); - qemu_vfree(cluster_data); - - return ret; -} - -static coroutine_fn int qcow2_co_writev(BlockDriverState *bs, - int64_t sector_num, - int remaining_sectors, - QEMUIOVector *qiov) -{ - BDRVQcowState *s = bs->opaque; - int index_in_cluster; - int n_end; - int ret; - int cur_nr_sectors; /* number of sectors in current iteration */ - uint64_t cluster_offset; - QEMUIOVector hd_qiov; - uint64_t bytes_done = 0; - uint8_t *cluster_data = NULL; - QCowL2Meta *l2meta = NULL; - - trace_qcow2_writev_start_req(qemu_coroutine_self(), sector_num, - remaining_sectors); - - qemu_iovec_init(&hd_qiov, qiov->niov); - - s->cluster_cache_offset = -1; /* disable compressed cache */ - - qemu_co_mutex_lock(&s->lock); - - while (remaining_sectors != 0) { - - l2meta = NULL; - - trace_qcow2_writev_start_part(qemu_coroutine_self()); - index_in_cluster = sector_num & (s->cluster_sectors - 1); - n_end = index_in_cluster + remaining_sectors; - if (s->crypt_method && - n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) { - n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors; - } - - ret = qcow2_alloc_cluster_offset(bs, sector_num << 9, - index_in_cluster, n_end, &cur_nr_sectors, &cluster_offset, &l2meta); - if (ret < 0) { - goto fail; - } - - assert((cluster_offset & 511) == 0); - - qemu_iovec_reset(&hd_qiov); - qemu_iovec_concat(&hd_qiov, qiov, bytes_done, - cur_nr_sectors * 512); - - if (s->crypt_method) { - if (!cluster_data) { - cluster_data = qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * - s->cluster_size); - } - - assert(hd_qiov.size <= - QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); - qemu_iovec_to_buf(&hd_qiov, 0, cluster_data, hd_qiov.size); - - qcow2_encrypt_sectors(s, sector_num, cluster_data, - cluster_data, cur_nr_sectors, 1, &s->aes_encrypt_key); - - qemu_iovec_reset(&hd_qiov); - qemu_iovec_add(&hd_qiov, cluster_data, - cur_nr_sectors * 512); - } - - qemu_co_mutex_unlock(&s->lock); - BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO); - trace_qcow2_writev_data(qemu_coroutine_self(), - (cluster_offset >> 9) + index_in_cluster); - ret = bdrv_co_writev(bs->file, - (cluster_offset >> 9) + index_in_cluster, - cur_nr_sectors, &hd_qiov); - qemu_co_mutex_lock(&s->lock); - if (ret < 0) { - goto fail; - } - - while (l2meta != NULL) { - QCowL2Meta *next; - - ret = qcow2_alloc_cluster_link_l2(bs, l2meta); - if (ret < 0) { - goto fail; - } - - /* Take the request off the list of running requests */ - if (l2meta->nb_clusters != 0) { - QLIST_REMOVE(l2meta, next_in_flight); - } - - qemu_co_queue_restart_all(&l2meta->dependent_requests); - - next = l2meta->next; - g_free(l2meta); - l2meta = next; - } - - remaining_sectors -= cur_nr_sectors; - sector_num += cur_nr_sectors; - bytes_done += cur_nr_sectors * 512; - trace_qcow2_writev_done_part(qemu_coroutine_self(), cur_nr_sectors); - } - ret = 0; - -fail: - qemu_co_mutex_unlock(&s->lock); - - while (l2meta != NULL) { - QCowL2Meta *next; - - if (l2meta->nb_clusters != 0) { - QLIST_REMOVE(l2meta, next_in_flight); - } - qemu_co_queue_restart_all(&l2meta->dependent_requests); - - next = l2meta->next; - g_free(l2meta); - l2meta = next; - } - - qemu_iovec_destroy(&hd_qiov); - qemu_vfree(cluster_data); - trace_qcow2_writev_done_req(qemu_coroutine_self(), ret); - - return ret; -} - -static void qcow2_close(BlockDriverState *bs) -{ - BDRVQcowState *s = bs->opaque; - g_free(s->l1_table); - - qcow2_cache_flush(bs, s->l2_table_cache); - qcow2_cache_flush(bs, s->refcount_block_cache); - - qcow2_mark_clean(bs); - - qcow2_cache_destroy(bs, s->l2_table_cache); - qcow2_cache_destroy(bs, s->refcount_block_cache); - - g_free(s->unknown_header_fields); - cleanup_unknown_header_ext(bs); - - g_free(s->cluster_cache); - qemu_vfree(s->cluster_data); - qcow2_refcount_close(bs); - qcow2_free_snapshots(bs); -} - -static void qcow2_invalidate_cache(BlockDriverState *bs) -{ - BDRVQcowState *s = bs->opaque; - int flags = s->flags; - AES_KEY aes_encrypt_key; - AES_KEY aes_decrypt_key; - uint32_t crypt_method = 0; - QDict *options; - - /* - * Backing files are read-only which makes all of their metadata immutable, - * that means we don't have to worry about reopening them here. - */ - - if (s->crypt_method) { - crypt_method = s->crypt_method; - memcpy(&aes_encrypt_key, &s->aes_encrypt_key, sizeof(aes_encrypt_key)); - memcpy(&aes_decrypt_key, &s->aes_decrypt_key, sizeof(aes_decrypt_key)); - } - - qcow2_close(bs); - - options = qdict_new(); - qdict_put(options, QCOW2_OPT_LAZY_REFCOUNTS, - qbool_from_int(s->use_lazy_refcounts)); - - memset(s, 0, sizeof(BDRVQcowState)); - qcow2_open(bs, options, flags); - - QDECREF(options); - - if (crypt_method) { - s->crypt_method = crypt_method; - memcpy(&s->aes_encrypt_key, &aes_encrypt_key, sizeof(aes_encrypt_key)); - memcpy(&s->aes_decrypt_key, &aes_decrypt_key, sizeof(aes_decrypt_key)); - } -} - -static size_t header_ext_add(char *buf, uint32_t magic, const void *s, - size_t len, size_t buflen) -{ - QCowExtension *ext_backing_fmt = (QCowExtension*) buf; - size_t ext_len = sizeof(QCowExtension) + ((len + 7) & ~7); - - if (buflen < ext_len) { - return -ENOSPC; - } - - *ext_backing_fmt = (QCowExtension) { - .magic = cpu_to_be32(magic), - .len = cpu_to_be32(len), - }; - memcpy(buf + sizeof(QCowExtension), s, len); - - return ext_len; -} - -/* - * Updates the qcow2 header, including the variable length parts of it, i.e. - * the backing file name and all extensions. qcow2 was not designed to allow - * such changes, so if we run out of space (we can only use the first cluster) - * this function may fail. - * - * Returns 0 on success, -errno in error cases. - */ -int qcow2_update_header(BlockDriverState *bs) -{ - BDRVQcowState *s = bs->opaque; - QCowHeader *header; - char *buf; - size_t buflen = s->cluster_size; - int ret; - uint64_t total_size; - uint32_t refcount_table_clusters; - size_t header_length; - Qcow2UnknownHeaderExtension *uext; - - buf = qemu_blockalign(bs, buflen); - - /* Header structure */ - header = (QCowHeader*) buf; - - if (buflen < sizeof(*header)) { - ret = -ENOSPC; - goto fail; - } - - header_length = sizeof(*header) + s->unknown_header_fields_size; - total_size = bs->total_sectors * BDRV_SECTOR_SIZE; - refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3); - - *header = (QCowHeader) { - /* Version 2 fields */ - .magic = cpu_to_be32(QCOW_MAGIC), - .version = cpu_to_be32(s->qcow_version), - .backing_file_offset = 0, - .backing_file_size = 0, - .cluster_bits = cpu_to_be32(s->cluster_bits), - .size = cpu_to_be64(total_size), - .crypt_method = cpu_to_be32(s->crypt_method_header), - .l1_size = cpu_to_be32(s->l1_size), - .l1_table_offset = cpu_to_be64(s->l1_table_offset), - .refcount_table_offset = cpu_to_be64(s->refcount_table_offset), - .refcount_table_clusters = cpu_to_be32(refcount_table_clusters), - .nb_snapshots = cpu_to_be32(s->nb_snapshots), - .snapshots_offset = cpu_to_be64(s->snapshots_offset), - - /* Version 3 fields */ - .incompatible_features = cpu_to_be64(s->incompatible_features), - .compatible_features = cpu_to_be64(s->compatible_features), - .autoclear_features = cpu_to_be64(s->autoclear_features), - .refcount_order = cpu_to_be32(3 + REFCOUNT_SHIFT), - .header_length = cpu_to_be32(header_length), - }; - - /* For older versions, write a shorter header */ - switch (s->qcow_version) { - case 2: - ret = offsetof(QCowHeader, incompatible_features); - break; - case 3: - ret = sizeof(*header); - break; - default: - ret = -EINVAL; - goto fail; - } - - buf += ret; - buflen -= ret; - memset(buf, 0, buflen); - - /* Preserve any unknown field in the header */ - if (s->unknown_header_fields_size) { - if (buflen < s->unknown_header_fields_size) { - ret = -ENOSPC; - goto fail; - } - - memcpy(buf, s->unknown_header_fields, s->unknown_header_fields_size); - buf += s->unknown_header_fields_size; - buflen -= s->unknown_header_fields_size; - } - - /* Backing file format header extension */ - if (*bs->backing_format) { - ret = header_ext_add(buf, QCOW2_EXT_MAGIC_BACKING_FORMAT, - bs->backing_format, strlen(bs->backing_format), - buflen); - if (ret < 0) { - goto fail; - } - - buf += ret; - buflen -= ret; - } - - /* Feature table */ - Qcow2Feature features[] = { - { - .type = QCOW2_FEAT_TYPE_INCOMPATIBLE, - .bit = QCOW2_INCOMPAT_DIRTY_BITNR, - .name = "dirty bit", - }, - { - .type = QCOW2_FEAT_TYPE_COMPATIBLE, - .bit = QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR, - .name = "lazy refcounts", - }, - }; - - ret = header_ext_add(buf, QCOW2_EXT_MAGIC_FEATURE_TABLE, - features, sizeof(features), buflen); - if (ret < 0) { - goto fail; - } - buf += ret; - buflen -= ret; - - /* Keep unknown header extensions */ - QLIST_FOREACH(uext, &s->unknown_header_ext, next) { - ret = header_ext_add(buf, uext->magic, uext->data, uext->len, buflen); - if (ret < 0) { - goto fail; - } - - buf += ret; - buflen -= ret; - } - - /* End of header extensions */ - ret = header_ext_add(buf, QCOW2_EXT_MAGIC_END, NULL, 0, buflen); - if (ret < 0) { - goto fail; - } - - buf += ret; - buflen -= ret; - - /* Backing file name */ - if (*bs->backing_file) { - size_t backing_file_len = strlen(bs->backing_file); - - if (buflen < backing_file_len) { - ret = -ENOSPC; - goto fail; - } - - /* Using strncpy is ok here, since buf is not NUL-terminated. */ - strncpy(buf, bs->backing_file, buflen); - - header->backing_file_offset = cpu_to_be64(buf - ((char*) header)); - header->backing_file_size = cpu_to_be32(backing_file_len); - } - - /* Write the new header */ - ret = bdrv_pwrite(bs->file, 0, header, s->cluster_size); - if (ret < 0) { - goto fail; - } - - ret = 0; -fail: - qemu_vfree(header); - return ret; -} - -static int qcow2_change_backing_file(BlockDriverState *bs, - const char *backing_file, const char *backing_fmt) -{ - pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: ""); - pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: ""); - - return qcow2_update_header(bs); -} - -static int preallocate(BlockDriverState *bs) -{ - uint64_t nb_sectors; - uint64_t offset; - uint64_t host_offset = 0; - int num; - int ret; - QCowL2Meta *meta; - - nb_sectors = bdrv_getlength(bs) >> 9; - offset = 0; - - while (nb_sectors) { - num = MIN(nb_sectors, INT_MAX >> 9); - ret = qcow2_alloc_cluster_offset(bs, offset, 0, num, &num, - &host_offset, &meta); - if (ret < 0) { - return ret; - } - - ret = qcow2_alloc_cluster_link_l2(bs, meta); - if (ret < 0) { - qcow2_free_any_clusters(bs, meta->alloc_offset, meta->nb_clusters, - QCOW2_DISCARD_NEVER); - return ret; - } - - /* There are no dependent requests, but we need to remove our request - * from the list of in-flight requests */ - if (meta != NULL) { - QLIST_REMOVE(meta, next_in_flight); - } - - /* TODO Preallocate data if requested */ - - nb_sectors -= num; - offset += num << 9; - } - - /* - * It is expected that the image file is large enough to actually contain - * all of the allocated clusters (otherwise we get failing reads after - * EOF). Extend the image to the last allocated sector. - */ - if (host_offset != 0) { - uint8_t buf[512]; - memset(buf, 0, 512); - ret = bdrv_write(bs->file, (host_offset >> 9) + num - 1, buf, 1); - if (ret < 0) { - return ret; - } - } - - return 0; -} - -static int qcow2_create2(const char *filename, int64_t total_size, - const char *backing_file, const char *backing_format, - int flags, size_t cluster_size, int prealloc, - QEMUOptionParameter *options, int version) -{ - /* Calculate cluster_bits */ - int cluster_bits; - cluster_bits = ffs(cluster_size) - 1; - if (cluster_bits < MIN_CLUSTER_BITS || cluster_bits > MAX_CLUSTER_BITS || - (1 << cluster_bits) != cluster_size) - { - error_report( - "Cluster size must be a power of two between %d and %dk", - 1 << MIN_CLUSTER_BITS, 1 << (MAX_CLUSTER_BITS - 10)); - return -EINVAL; - } - - /* - * Open the image file and write a minimal qcow2 header. - * - * We keep things simple and start with a zero-sized image. We also - * do without refcount blocks or a L1 table for now. We'll fix the - * inconsistency later. - * - * We do need a refcount table because growing the refcount table means - * allocating two new refcount blocks - the seconds of which would be at - * 2 GB for 64k clusters, and we don't want to have a 2 GB initial file - * size for any qcow2 image. - */ - BlockDriverState* bs; - QCowHeader header; - uint8_t* refcount_table; - int ret; - - ret = bdrv_create_file(filename, options); - if (ret < 0) { - return ret; - } - - ret = bdrv_file_open(&bs, filename, NULL, BDRV_O_RDWR); - if (ret < 0) { - return ret; - } - - /* Write the header */ - memset(&header, 0, sizeof(header)); - header.magic = cpu_to_be32(QCOW_MAGIC); - header.version = cpu_to_be32(version); - header.cluster_bits = cpu_to_be32(cluster_bits); - header.size = cpu_to_be64(0); - header.l1_table_offset = cpu_to_be64(0); - header.l1_size = cpu_to_be32(0); - header.refcount_table_offset = cpu_to_be64(cluster_size); - header.refcount_table_clusters = cpu_to_be32(1); - header.refcount_order = cpu_to_be32(3 + REFCOUNT_SHIFT); - header.header_length = cpu_to_be32(sizeof(header)); - - if (flags & BLOCK_FLAG_ENCRYPT) { - header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES); - } else { - header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); - } - - if (flags & BLOCK_FLAG_LAZY_REFCOUNTS) { - header.compatible_features |= - cpu_to_be64(QCOW2_COMPAT_LAZY_REFCOUNTS); - } - - ret = bdrv_pwrite(bs, 0, &header, sizeof(header)); - if (ret < 0) { - goto out; - } - - /* Write an empty refcount table */ - refcount_table = g_malloc0(cluster_size); - ret = bdrv_pwrite(bs, cluster_size, refcount_table, cluster_size); - g_free(refcount_table); - - if (ret < 0) { - goto out; - } - - bdrv_close(bs); - - /* - * And now open the image and make it consistent first (i.e. increase the - * refcount of the cluster that is occupied by the header and the refcount - * table) - */ - BlockDriver* drv = bdrv_find_format("qcow2"); - assert(drv != NULL); - ret = bdrv_open(bs, filename, NULL, - BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, drv); - if (ret < 0) { - goto out; - } - - ret = qcow2_alloc_clusters(bs, 2 * cluster_size); - if (ret < 0) { - goto out; - - } else if (ret != 0) { - error_report("Huh, first cluster in empty image is already in use?"); - abort(); - } - - /* Okay, now that we have a valid image, let's give it the right size */ - ret = bdrv_truncate(bs, total_size * BDRV_SECTOR_SIZE); - if (ret < 0) { - goto out; - } - - /* Want a backing file? There you go.*/ - if (backing_file) { - ret = bdrv_change_backing_file(bs, backing_file, backing_format); - if (ret < 0) { - goto out; - } - } - - /* And if we're supposed to preallocate metadata, do that now */ - if (prealloc) { - BDRVQcowState *s = bs->opaque; - qemu_co_mutex_lock(&s->lock); - ret = preallocate(bs); - qemu_co_mutex_unlock(&s->lock); - if (ret < 0) { - goto out; - } - } - - ret = 0; -out: - bdrv_delete(bs); - return ret; -} - -static int qcow2_create(const char *filename, QEMUOptionParameter *options) -{ - const char *backing_file = NULL; - const char *backing_fmt = NULL; - uint64_t sectors = 0; - int flags = 0; - size_t cluster_size = DEFAULT_CLUSTER_SIZE; - int prealloc = 0; - int version = 2; - - /* Read out options */ - while (options && options->name) { - if (!strcmp(options->name, BLOCK_OPT_SIZE)) { - sectors = options->value.n / 512; - } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) { - backing_file = options->value.s; - } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FMT)) { - backing_fmt = options->value.s; - } else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) { - flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0; - } else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) { - if (options->value.n) { - cluster_size = options->value.n; - } - } else if (!strcmp(options->name, BLOCK_OPT_PREALLOC)) { - if (!options->value.s || !strcmp(options->value.s, "off")) { - prealloc = 0; - } else if (!strcmp(options->value.s, "metadata")) { - prealloc = 1; - } else { - fprintf(stderr, "Invalid preallocation mode: '%s'\n", - options->value.s); - return -EINVAL; - } - } else if (!strcmp(options->name, BLOCK_OPT_COMPAT_LEVEL)) { - if (!options->value.s || !strcmp(options->value.s, "0.10")) { - version = 2; - } else if (!strcmp(options->value.s, "1.1")) { - version = 3; - } else { - fprintf(stderr, "Invalid compatibility level: '%s'\n", - options->value.s); - return -EINVAL; - } - } else if (!strcmp(options->name, BLOCK_OPT_LAZY_REFCOUNTS)) { - flags |= options->value.n ? BLOCK_FLAG_LAZY_REFCOUNTS : 0; - } - options++; - } - - if (backing_file && prealloc) { - fprintf(stderr, "Backing file and preallocation cannot be used at " - "the same time\n"); - return -EINVAL; - } - - if (version < 3 && (flags & BLOCK_FLAG_LAZY_REFCOUNTS)) { - fprintf(stderr, "Lazy refcounts only supported with compatibility " - "level 1.1 and above (use compat=1.1 or greater)\n"); - return -EINVAL; - } - - return qcow2_create2(filename, sectors, backing_file, backing_fmt, flags, - cluster_size, prealloc, options, version); -} - -static int qcow2_make_empty(BlockDriverState *bs) -{ -#if 0 - /* XXX: not correct */ - BDRVQcowState *s = bs->opaque; - uint32_t l1_length = s->l1_size * sizeof(uint64_t); - int ret; - - memset(s->l1_table, 0, l1_length); - if (bdrv_pwrite(bs->file, s->l1_table_offset, s->l1_table, l1_length) < 0) - return -1; - ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length); - if (ret < 0) - return ret; - - l2_cache_reset(bs); -#endif - return 0; -} - -static coroutine_fn int qcow2_co_write_zeroes(BlockDriverState *bs, - int64_t sector_num, int nb_sectors) -{ - int ret; - BDRVQcowState *s = bs->opaque; - - /* Emulate misaligned zero writes */ - if (sector_num % s->cluster_sectors || nb_sectors % s->cluster_sectors) { - return -ENOTSUP; - } - - /* Whatever is left can use real zero clusters */ - qemu_co_mutex_lock(&s->lock); - ret = qcow2_zero_clusters(bs, sector_num << BDRV_SECTOR_BITS, - nb_sectors); - qemu_co_mutex_unlock(&s->lock); - - return ret; -} - -static coroutine_fn int qcow2_co_discard(BlockDriverState *bs, - int64_t sector_num, int nb_sectors) -{ - int ret; - BDRVQcowState *s = bs->opaque; - - qemu_co_mutex_lock(&s->lock); - ret = qcow2_discard_clusters(bs, sector_num << BDRV_SECTOR_BITS, - nb_sectors); - qemu_co_mutex_unlock(&s->lock); - return ret; -} - -static int qcow2_truncate(BlockDriverState *bs, int64_t offset) -{ - BDRVQcowState *s = bs->opaque; - int64_t new_l1_size; - int ret; - - if (offset & 511) { - error_report("The new size must be a multiple of 512"); - return -EINVAL; - } - - /* cannot proceed if image has snapshots */ - if (s->nb_snapshots) { - error_report("Can't resize an image which has snapshots"); - return -ENOTSUP; - } - - /* shrinking is currently not supported */ - if (offset < bs->total_sectors * 512) { - error_report("qcow2 doesn't support shrinking images yet"); - return -ENOTSUP; - } - - new_l1_size = size_to_l1(s, offset); - ret = qcow2_grow_l1_table(bs, new_l1_size, true); - if (ret < 0) { - return ret; - } - - /* write updated header.size */ - offset = cpu_to_be64(offset); - ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size), - &offset, sizeof(uint64_t)); - if (ret < 0) { - return ret; - } - - s->l1_vm_state_index = new_l1_size; - return 0; -} - -/* XXX: put compressed sectors first, then all the cluster aligned - tables to avoid losing bytes in alignment */ -static int qcow2_write_compressed(BlockDriverState *bs, int64_t sector_num, - const uint8_t *buf, int nb_sectors) -{ - BDRVQcowState *s = bs->opaque; - z_stream strm; - int ret, out_len; - uint8_t *out_buf; - uint64_t cluster_offset; - - if (nb_sectors == 0) { - /* align end of file to a sector boundary to ease reading with - sector based I/Os */ - cluster_offset = bdrv_getlength(bs->file); - cluster_offset = (cluster_offset + 511) & ~511; - bdrv_truncate(bs->file, cluster_offset); - return 0; - } - - if (nb_sectors != s->cluster_sectors) { - ret = -EINVAL; - - /* Zero-pad last write if image size is not cluster aligned */ - if (sector_num + nb_sectors == bs->total_sectors && - nb_sectors < s->cluster_sectors) { - uint8_t *pad_buf = qemu_blockalign(bs, s->cluster_size); - memset(pad_buf, 0, s->cluster_size); - memcpy(pad_buf, buf, nb_sectors * BDRV_SECTOR_SIZE); - ret = qcow2_write_compressed(bs, sector_num, - pad_buf, s->cluster_sectors); - qemu_vfree(pad_buf); - } - return ret; - } - - out_buf = g_malloc(s->cluster_size + (s->cluster_size / 1000) + 128); - - /* best compression, small window, no zlib header */ - memset(&strm, 0, sizeof(strm)); - ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, - Z_DEFLATED, -12, - 9, Z_DEFAULT_STRATEGY); - if (ret != 0) { - ret = -EINVAL; - goto fail; - } - - strm.avail_in = s->cluster_size; - strm.next_in = (uint8_t *)buf; - strm.avail_out = s->cluster_size; - strm.next_out = out_buf; - - ret = deflate(&strm, Z_FINISH); - if (ret != Z_STREAM_END && ret != Z_OK) { - deflateEnd(&strm); - ret = -EINVAL; - goto fail; - } - out_len = strm.next_out - out_buf; - - deflateEnd(&strm); - - if (ret != Z_STREAM_END || out_len >= s->cluster_size) { - /* could not compress: write normal cluster */ - ret = bdrv_write(bs, sector_num, buf, s->cluster_sectors); - if (ret < 0) { - goto fail; - } - } else { - cluster_offset = qcow2_alloc_compressed_cluster_offset(bs, - sector_num << 9, out_len); - if (!cluster_offset) { - ret = -EIO; - goto fail; - } - cluster_offset &= s->cluster_offset_mask; - BLKDBG_EVENT(bs->file, BLKDBG_WRITE_COMPRESSED); - ret = bdrv_pwrite(bs->file, cluster_offset, out_buf, out_len); - if (ret < 0) { - goto fail; - } - } - - ret = 0; -fail: - g_free(out_buf); - return ret; -} - -static coroutine_fn int qcow2_co_flush_to_os(BlockDriverState *bs) -{ - BDRVQcowState *s = bs->opaque; - int ret; - - qemu_co_mutex_lock(&s->lock); - ret = qcow2_cache_flush(bs, s->l2_table_cache); - if (ret < 0) { - qemu_co_mutex_unlock(&s->lock); - return ret; - } - - if (qcow2_need_accurate_refcounts(s)) { - ret = qcow2_cache_flush(bs, s->refcount_block_cache); - if (ret < 0) { - qemu_co_mutex_unlock(&s->lock); - return ret; - } - } - qemu_co_mutex_unlock(&s->lock); - - return 0; -} - -static int64_t qcow2_vm_state_offset(BDRVQcowState *s) -{ - return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits); -} - -static int qcow2_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) -{ - BDRVQcowState *s = bs->opaque; - bdi->cluster_size = s->cluster_size; - bdi->vm_state_offset = qcow2_vm_state_offset(s); - return 0; -} - -#if 0 -static void dump_refcounts(BlockDriverState *bs) -{ - BDRVQcowState *s = bs->opaque; - int64_t nb_clusters, k, k1, size; - int refcount; - - size = bdrv_getlength(bs->file); - nb_clusters = size_to_clusters(s, size); - for(k = 0; k < nb_clusters;) { - k1 = k; - refcount = get_refcount(bs, k); - k++; - while (k < nb_clusters && get_refcount(bs, k) == refcount) - k++; - printf("%" PRId64 ": refcount=%d nb=%" PRId64 "\n", k, refcount, - k - k1); - } -} -#endif - -static int qcow2_save_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, - int64_t pos) -{ - BDRVQcowState *s = bs->opaque; - int growable = bs->growable; - int ret; - - BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE); - bs->growable = 1; - ret = bdrv_pwritev(bs, qcow2_vm_state_offset(s) + pos, qiov); - bs->growable = growable; - - return ret; -} - -static int qcow2_load_vmstate(BlockDriverState *bs, uint8_t *buf, - int64_t pos, int size) -{ - BDRVQcowState *s = bs->opaque; - int growable = bs->growable; - int ret; - - BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_LOAD); - bs->growable = 1; - ret = bdrv_pread(bs, qcow2_vm_state_offset(s) + pos, buf, size); - bs->growable = growable; - - return ret; -} - -static QEMUOptionParameter qcow2_create_options[] = { - { - .name = BLOCK_OPT_SIZE, - .type = OPT_SIZE, - .help = "Virtual disk size" - }, - { - .name = BLOCK_OPT_COMPAT_LEVEL, - .type = OPT_STRING, - .help = "Compatibility level (0.10 or 1.1)" - }, - { - .name = BLOCK_OPT_BACKING_FILE, - .type = OPT_STRING, - .help = "File name of a base image" - }, - { - .name = BLOCK_OPT_BACKING_FMT, - .type = OPT_STRING, - .help = "Image format of the base image" - }, - { - .name = BLOCK_OPT_ENCRYPT, - .type = OPT_FLAG, - .help = "Encrypt the image" - }, - { - .name = BLOCK_OPT_CLUSTER_SIZE, - .type = OPT_SIZE, - .help = "qcow2 cluster size", - .value = { .n = DEFAULT_CLUSTER_SIZE }, - }, - { - .name = BLOCK_OPT_PREALLOC, - .type = OPT_STRING, - .help = "Preallocation mode (allowed values: off, metadata)" - }, - { - .name = BLOCK_OPT_LAZY_REFCOUNTS, - .type = OPT_FLAG, - .help = "Postpone refcount updates", - }, - { NULL } -}; - -static BlockDriver bdrv_qcow2 = { - .format_name = "qcow2", - .instance_size = sizeof(BDRVQcowState), - .bdrv_probe = qcow2_probe, - .bdrv_open = qcow2_open, - .bdrv_close = qcow2_close, - .bdrv_reopen_prepare = qcow2_reopen_prepare, - .bdrv_create = qcow2_create, - .bdrv_has_zero_init = bdrv_has_zero_init_1, - .bdrv_co_is_allocated = qcow2_co_is_allocated, - .bdrv_set_key = qcow2_set_key, - .bdrv_make_empty = qcow2_make_empty, - - .bdrv_co_readv = qcow2_co_readv, - .bdrv_co_writev = qcow2_co_writev, - .bdrv_co_flush_to_os = qcow2_co_flush_to_os, - - .bdrv_co_write_zeroes = qcow2_co_write_zeroes, - .bdrv_co_discard = qcow2_co_discard, - .bdrv_truncate = qcow2_truncate, - .bdrv_write_compressed = qcow2_write_compressed, - - .bdrv_snapshot_create = qcow2_snapshot_create, - .bdrv_snapshot_goto = qcow2_snapshot_goto, - .bdrv_snapshot_delete = qcow2_snapshot_delete, - .bdrv_snapshot_list = qcow2_snapshot_list, - .bdrv_snapshot_load_tmp = qcow2_snapshot_load_tmp, - .bdrv_get_info = qcow2_get_info, - - .bdrv_save_vmstate = qcow2_save_vmstate, - .bdrv_load_vmstate = qcow2_load_vmstate, - - .bdrv_change_backing_file = qcow2_change_backing_file, - - .bdrv_invalidate_cache = qcow2_invalidate_cache, - - .create_options = qcow2_create_options, - .bdrv_check = qcow2_check, -}; - -static void bdrv_qcow2_init(void) -{ - bdrv_register(&bdrv_qcow2); -} - -block_init(bdrv_qcow2_init); |