X-Git-Url: http://git.maemo.org/git/?a=blobdiff_plain;f=block-qcow2.c;h=afbf7feb56b87686817975f4738f42a239bdeed0;hb=221f715d90ec5fec569a19119887445c037bca86;hp=b05fd14669484c78ec9f4cc6fb049fa927c4fe68;hpb=52d893ecf98a43d17f9b65c5a22a130ecacd9bf1;p=qemu diff --git a/block-qcow2.c b/block-qcow2.c index b05fd14..afbf7fe 100644 --- a/block-qcow2.c +++ b/block-qcow2.c @@ -52,6 +52,8 @@ #define QCOW_CRYPT_NONE 0 #define QCOW_CRYPT_AES 1 +#define QCOW_MAX_CRYPT_CLUSTERS 32 + /* indicate that the refcount of the referenced cluster is exactly one. */ #define QCOW_OFLAG_COPIED (1LL << 63) /* indicate that the cluster is compressed (they never have the copied flag) */ @@ -59,10 +61,6 @@ #define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */ -#ifndef offsetof -#define offsetof(type, field) ((size_t) &((type *)0)->field) -#endif - typedef struct QCowHeader { uint32_t magic; uint32_t version; @@ -191,6 +189,14 @@ static int qcow_open(BlockDriverState *bs, const char *filename, int flags) int len, i, shift, ret; QCowHeader header; + /* Performance is terrible right now with cache=writethrough due mainly + * to reference count updates. If the user does not explicitly specify + * a caching type, force to writeback caching. + */ + if ((flags & BDRV_O_CACHE_DEF)) { + flags |= BDRV_O_CACHE_WB; + flags &= ~BDRV_O_CACHE_DEF; + } ret = bdrv_file_open(&s->hd, filename, flags); if (ret < 0) return ret; @@ -247,8 +253,6 @@ static int qcow_open(BlockDriverState *bs, const char *filename, int flags) goto fail; s->l1_table_offset = header.l1_table_offset; s->l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t)); - if (!s->l1_table) - goto fail; if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)) != s->l1_size * sizeof(uint64_t)) goto fail; @@ -257,15 +261,10 @@ static int qcow_open(BlockDriverState *bs, const char *filename, int flags) } /* alloc L2 cache */ s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); - if (!s->l2_cache) - goto fail; s->cluster_cache = qemu_malloc(s->cluster_size); - if (!s->cluster_cache) - goto fail; /* one more sector for decompressed data alignment */ - s->cluster_data = qemu_malloc(s->cluster_size + 512); - if (!s->cluster_data) - goto fail; + s->cluster_data = qemu_malloc(QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size + + 512); s->cluster_cache_offset = -1; if (refcount_init(bs) < 0) @@ -430,8 +429,7 @@ static int grow_l1_table(BlockDriverState *bs, int min_size) int new_l1_size, new_l1_size2, ret, i; uint64_t *new_l1_table; uint64_t new_l1_table_offset; - uint64_t data64; - uint32_t data32; + uint8_t data[12]; new_l1_size = s->l1_size; if (min_size <= new_l1_size) @@ -445,8 +443,6 @@ static int grow_l1_table(BlockDriverState *bs, int min_size) new_l1_size2 = sizeof(uint64_t) * new_l1_size; new_l1_table = qemu_mallocz(new_l1_size2); - if (!new_l1_table) - return -ENOMEM; memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t)); /* write new table (align to cluster) */ @@ -461,13 +457,10 @@ static int grow_l1_table(BlockDriverState *bs, int min_size) new_l1_table[i] = be64_to_cpu(new_l1_table[i]); /* set new table */ - data64 = cpu_to_be64(new_l1_table_offset); - if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_table_offset), - &data64, sizeof(data64)) != sizeof(data64)) - goto fail; - data32 = cpu_to_be32(new_l1_size); - if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), - &data32, sizeof(data32)) != sizeof(data32)) + cpu_to_be32w((uint32_t*)data, new_l1_size); + cpu_to_be64w((uint64_t*)(data + 4), new_l1_table_offset); + if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), data, + sizeof(data)) != sizeof(data)) goto fail; qemu_free(s->l1_table); free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t)); @@ -606,35 +599,91 @@ static uint64_t *l2_allocate(BlockDriverState *bs, int l1_index) return l2_table; } +static int size_to_clusters(BDRVQcowState *s, int64_t size) +{ + return (size + (s->cluster_size - 1)) >> s->cluster_bits; +} + +static int count_contiguous_clusters(uint64_t nb_clusters, int cluster_size, + uint64_t *l2_table, uint64_t start, uint64_t mask) +{ + int i; + uint64_t offset = be64_to_cpu(l2_table[0]) & ~mask; + + if (!offset) + return 0; + + for (i = start; i < start + nb_clusters; i++) + if (offset + i * cluster_size != (be64_to_cpu(l2_table[i]) & ~mask)) + break; + + return (i - start); +} + +static int count_contiguous_free_clusters(uint64_t nb_clusters, uint64_t *l2_table) +{ + int i = 0; + + while(nb_clusters-- && l2_table[i] == 0) + i++; + + return i; +} + /* * get_cluster_offset * * For a given offset of the disk image, return cluster offset in * qcow2 file. * + * on entry, *num is the number of contiguous clusters we'd like to + * access following offset. + * + * on exit, *num is the number of contiguous clusters we can read. + * * Return 1, if the offset is found * Return 0, otherwise. * */ -static uint64_t get_cluster_offset(BlockDriverState *bs, uint64_t offset) +static uint64_t get_cluster_offset(BlockDriverState *bs, + uint64_t offset, int *num) { BDRVQcowState *s = bs->opaque; int l1_index, l2_index; uint64_t l2_offset, *l2_table, cluster_offset; + int l1_bits, c; + int index_in_cluster, nb_available, nb_needed, nb_clusters; + + index_in_cluster = (offset >> 9) & (s->cluster_sectors - 1); + nb_needed = *num + index_in_cluster; + + l1_bits = s->l2_bits + s->cluster_bits; + + /* compute how many bytes there are between the offset and + * the end of the l1 entry + */ + + nb_available = (1 << l1_bits) - (offset & ((1 << l1_bits) - 1)); + + /* compute the number of available sectors */ + + nb_available = (nb_available >> 9) + index_in_cluster; + + cluster_offset = 0; /* seek the the l2 offset in the l1 table */ - l1_index = offset >> (s->l2_bits + s->cluster_bits); + l1_index = offset >> l1_bits; if (l1_index >= s->l1_size) - return 0; + goto out; l2_offset = s->l1_table[l1_index]; /* seek the l2 table of the given l2 offset */ if (!l2_offset) - return 0; + goto out; /* load the l2 table in memory */ @@ -647,6 +696,23 @@ static uint64_t get_cluster_offset(BlockDriverState *bs, uint64_t offset) l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1); cluster_offset = be64_to_cpu(l2_table[l2_index]); + nb_clusters = size_to_clusters(s, nb_needed << 9); + + if (!cluster_offset) { + /* how many empty clusters ? */ + c = count_contiguous_free_clusters(nb_clusters, &l2_table[l2_index]); + } else { + /* how many allocated clusters ? */ + c = count_contiguous_clusters(nb_clusters, s->cluster_size, + &l2_table[l2_index], 0, QCOW_OFLAG_COPIED); + } + + nb_available = (c * s->cluster_sectors); +out: + if (nb_available > nb_needed) + nb_available = nb_needed; + + *num = nb_available - index_in_cluster; return cluster_offset & ~QCOW_OFLAG_COPIED; } @@ -659,13 +725,10 @@ static uint64_t get_cluster_offset(BlockDriverState *bs, uint64_t offset) */ static void free_any_clusters(BlockDriverState *bs, - uint64_t cluster_offset) + uint64_t cluster_offset, int nb_clusters) { BDRVQcowState *s = bs->opaque; - if (cluster_offset == 0) - return; - /* free the cluster */ if (cluster_offset & QCOW_OFLAG_COMPRESSED) { @@ -677,7 +740,9 @@ static void free_any_clusters(BlockDriverState *bs, return; } - free_clusters(bs, cluster_offset, s->cluster_size); + free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits); + + return; } /* @@ -768,7 +833,8 @@ static uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs, if (cluster_offset & QCOW_OFLAG_COPIED) return cluster_offset & ~QCOW_OFLAG_COPIED; - free_any_clusters(bs, cluster_offset); + if (cluster_offset) + free_any_clusters(bs, cluster_offset, 1); cluster_offset = alloc_bytes(bs, compressed_size); nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) - @@ -791,6 +857,69 @@ static uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs, return cluster_offset; } +typedef struct QCowL2Meta +{ + uint64_t offset; + int n_start; + int nb_available; + int nb_clusters; +} QCowL2Meta; + +static int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset, + QCowL2Meta *m) +{ + BDRVQcowState *s = bs->opaque; + int i, j = 0, l2_index, ret; + uint64_t *old_cluster, start_sect, l2_offset, *l2_table; + + if (m->nb_clusters == 0) + return 0; + + old_cluster = qemu_malloc(m->nb_clusters * sizeof(uint64_t)); + + /* copy content of unmodified sectors */ + start_sect = (m->offset & ~(s->cluster_size - 1)) >> 9; + if (m->n_start) { + ret = copy_sectors(bs, start_sect, cluster_offset, 0, m->n_start); + if (ret < 0) + goto err; + } + + if (m->nb_available & (s->cluster_sectors - 1)) { + uint64_t end = m->nb_available & ~(uint64_t)(s->cluster_sectors - 1); + ret = copy_sectors(bs, start_sect + end, cluster_offset + (end << 9), + m->nb_available - end, s->cluster_sectors); + if (ret < 0) + goto err; + } + + ret = -EIO; + /* update L2 table */ + if (!get_cluster_table(bs, m->offset, &l2_table, &l2_offset, &l2_index)) + goto err; + + for (i = 0; i < m->nb_clusters; i++) { + if(l2_table[l2_index + i] != 0) + old_cluster[j++] = l2_table[l2_index + i]; + + l2_table[l2_index + i] = cpu_to_be64((cluster_offset + + (i << s->cluster_bits)) | QCOW_OFLAG_COPIED); + } + + if (bdrv_pwrite(s->hd, l2_offset + l2_index * sizeof(uint64_t), + l2_table + l2_index, m->nb_clusters * sizeof(uint64_t)) != + m->nb_clusters * sizeof(uint64_t)) + goto err; + + for (i = 0; i < j; i++) + free_any_clusters(bs, old_cluster[i], 1); + + ret = 0; +err: + qemu_free(old_cluster); + return ret; + } + /* * alloc_cluster_offset * @@ -806,51 +935,74 @@ static uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs, static uint64_t alloc_cluster_offset(BlockDriverState *bs, uint64_t offset, - int n_start, int n_end) + int n_start, int n_end, + int *num, QCowL2Meta *m) { BDRVQcowState *s = bs->opaque; int l2_index, ret; uint64_t l2_offset, *l2_table, cluster_offset; + int nb_clusters, i = 0; ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index); if (ret == 0) return 0; + nb_clusters = size_to_clusters(s, n_end << 9); + + nb_clusters = MIN(nb_clusters, s->l2_size - l2_index); + cluster_offset = be64_to_cpu(l2_table[l2_index]); - if (cluster_offset & QCOW_OFLAG_COPIED) - return cluster_offset & ~QCOW_OFLAG_COPIED; - free_any_clusters(bs, cluster_offset); + /* We keep all QCOW_OFLAG_COPIED clusters */ - /* allocate a new cluster */ + if (cluster_offset & QCOW_OFLAG_COPIED) { + nb_clusters = count_contiguous_clusters(nb_clusters, s->cluster_size, + &l2_table[l2_index], 0, 0); - cluster_offset = alloc_clusters(bs, s->cluster_size); + cluster_offset &= ~QCOW_OFLAG_COPIED; + m->nb_clusters = 0; - /* we must initialize the cluster content which won't be - written */ + goto out; + } - if ((n_end - n_start) < s->cluster_sectors) { - uint64_t start_sect; + /* for the moment, multiple compressed clusters are not managed */ - start_sect = (offset & ~(s->cluster_size - 1)) >> 9; - ret = copy_sectors(bs, start_sect, - cluster_offset, 0, n_start); - if (ret < 0) - return 0; - ret = copy_sectors(bs, start_sect, - cluster_offset, n_end, s->cluster_sectors); - if (ret < 0) - return 0; + if (cluster_offset & QCOW_OFLAG_COMPRESSED) + nb_clusters = 1; + + /* how many available clusters ? */ + + while (i < nb_clusters) { + i += count_contiguous_clusters(nb_clusters - i, s->cluster_size, + &l2_table[l2_index], i, 0); + + if(be64_to_cpu(l2_table[l2_index + i])) + break; + + i += count_contiguous_free_clusters(nb_clusters - i, + &l2_table[l2_index + i]); + + cluster_offset = be64_to_cpu(l2_table[l2_index + i]); + + if ((cluster_offset & QCOW_OFLAG_COPIED) || + (cluster_offset & QCOW_OFLAG_COMPRESSED)) + break; } + nb_clusters = i; - /* update L2 table */ + /* allocate a new cluster */ - l2_table[l2_index] = cpu_to_be64(cluster_offset | QCOW_OFLAG_COPIED); - if (bdrv_pwrite(s->hd, - l2_offset + l2_index * sizeof(uint64_t), - l2_table + l2_index, - sizeof(uint64_t)) != sizeof(uint64_t)) - return 0; + cluster_offset = alloc_clusters(bs, nb_clusters * s->cluster_size); + + /* save info needed for meta data update */ + m->offset = offset; + m->n_start = n_start; + m->nb_clusters = nb_clusters; + +out: + m->nb_available = MIN(nb_clusters << (s->cluster_bits - 9), n_end); + + *num = m->nb_available - n_start; return cluster_offset; } @@ -858,16 +1010,11 @@ static uint64_t alloc_cluster_offset(BlockDriverState *bs, static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum) { - BDRVQcowState *s = bs->opaque; - int index_in_cluster, n; uint64_t cluster_offset; - cluster_offset = get_cluster_offset(bs, sector_num << 9); - index_in_cluster = sector_num & (s->cluster_sectors - 1); - n = s->cluster_sectors - index_in_cluster; - if (n > nb_sectors) - n = nb_sectors; - *pnum = n; + *pnum = nb_sectors; + cluster_offset = get_cluster_offset(bs, sector_num << 9, pnum); + return (cluster_offset != 0); } @@ -944,11 +1091,9 @@ static int qcow_read(BlockDriverState *bs, int64_t sector_num, uint64_t cluster_offset; while (nb_sectors > 0) { - cluster_offset = get_cluster_offset(bs, sector_num << 9); + n = nb_sectors; + cluster_offset = get_cluster_offset(bs, sector_num << 9, &n); index_in_cluster = sector_num & (s->cluster_sectors - 1); - n = s->cluster_sectors - index_in_cluster; - if (n > nb_sectors) - n = nb_sectors; if (!cluster_offset) { if (bs->backing_hd) { /* read from the base image */ @@ -987,15 +1132,18 @@ static int qcow_write(BlockDriverState *bs, int64_t sector_num, BDRVQcowState *s = bs->opaque; int ret, index_in_cluster, n; uint64_t cluster_offset; + int n_end; + QCowL2Meta l2meta; while (nb_sectors > 0) { index_in_cluster = sector_num & (s->cluster_sectors - 1); - n = s->cluster_sectors - index_in_cluster; - if (n > nb_sectors) - n = nb_sectors; + n_end = index_in_cluster + nb_sectors; + if (s->crypt_method && + n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) + n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors; cluster_offset = alloc_cluster_offset(bs, sector_num << 9, index_in_cluster, - index_in_cluster + n); + n_end, &n, &l2meta); if (!cluster_offset) return -1; if (s->crypt_method) { @@ -1006,8 +1154,10 @@ static int qcow_write(BlockDriverState *bs, int64_t sector_num, } else { ret = bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512); } - if (ret != n * 512) + if (ret != n * 512 || alloc_cluster_link_l2(bs, cluster_offset, &l2meta) < 0) { + free_any_clusters(bs, cluster_offset, l2meta.nb_clusters); return -1; + } nb_sectors -= n; sector_num += n; buf += n * 512; @@ -1025,8 +1175,33 @@ typedef struct QCowAIOCB { uint64_t cluster_offset; uint8_t *cluster_data; BlockDriverAIOCB *hd_aiocb; + QEMUBH *bh; + QCowL2Meta l2meta; } QCowAIOCB; +static void qcow_aio_read_cb(void *opaque, int ret); +static void qcow_aio_read_bh(void *opaque) +{ + QCowAIOCB *acb = opaque; + qemu_bh_delete(acb->bh); + acb->bh = NULL; + qcow_aio_read_cb(opaque, 0); +} + +static int qcow_schedule_bh(QEMUBHFunc *cb, QCowAIOCB *acb) +{ + if (acb->bh) + return -EIO; + + acb->bh = qemu_bh_new(cb, acb); + if (!acb->bh) + return -EIO; + + qemu_bh_schedule(acb->bh); + + return 0; +} + static void qcow_aio_read_cb(void *opaque, int ret) { QCowAIOCB *acb = opaque; @@ -1036,13 +1211,12 @@ static void qcow_aio_read_cb(void *opaque, int ret) acb->hd_aiocb = NULL; if (ret < 0) { - fail: +fail: acb->common.cb(acb->common.opaque, ret); qemu_aio_release(acb); return; } - redo: /* post process the read buffer */ if (!acb->cluster_offset) { /* nothing to do */ @@ -1068,11 +1242,9 @@ static void qcow_aio_read_cb(void *opaque, int ret) } /* prepare next AIO request */ - acb->cluster_offset = get_cluster_offset(bs, acb->sector_num << 9); + acb->n = acb->nb_sectors; + acb->cluster_offset = get_cluster_offset(bs, acb->sector_num << 9, &acb->n); index_in_cluster = acb->sector_num & (s->cluster_sectors - 1); - acb->n = s->cluster_sectors - index_in_cluster; - if (acb->n > acb->nb_sectors) - acb->n = acb->nb_sectors; if (!acb->cluster_offset) { if (bs->backing_hd) { @@ -1085,12 +1257,16 @@ static void qcow_aio_read_cb(void *opaque, int ret) if (acb->hd_aiocb == NULL) goto fail; } else { - goto redo; + ret = qcow_schedule_bh(qcow_aio_read_bh, acb); + if (ret < 0) + goto fail; } } else { /* Note: in this case, no need to wait */ memset(acb->buf, 0, 512 * acb->n); - goto redo; + ret = qcow_schedule_bh(qcow_aio_read_bh, acb); + if (ret < 0) + goto fail; } } else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) { /* add AIO support for compressed blocks ? */ @@ -1098,7 +1274,9 @@ static void qcow_aio_read_cb(void *opaque, int ret) goto fail; memcpy(acb->buf, s->cluster_cache + index_in_cluster * 512, 512 * acb->n); - goto redo; + ret = qcow_schedule_bh(qcow_aio_read_bh, acb); + if (ret < 0) + goto fail; } else { if ((acb->cluster_offset & 511) != 0) { ret = -EIO; @@ -1127,6 +1305,7 @@ static QCowAIOCB *qcow_aio_setup(BlockDriverState *bs, acb->nb_sectors = nb_sectors; acb->n = 0; acb->cluster_offset = 0; + acb->l2meta.nb_clusters = 0; return acb; } @@ -1150,8 +1329,8 @@ static void qcow_aio_write_cb(void *opaque, int ret) BlockDriverState *bs = acb->common.bs; BDRVQcowState *s = bs->opaque; int index_in_cluster; - uint64_t cluster_offset; const uint8_t *src_buf; + int n_end; acb->hd_aiocb = NULL; @@ -1162,6 +1341,11 @@ static void qcow_aio_write_cb(void *opaque, int ret) return; } + if (alloc_cluster_link_l2(bs, acb->cluster_offset, &acb->l2meta) < 0) { + free_any_clusters(bs, acb->cluster_offset, acb->l2meta.nb_clusters); + goto fail; + } + acb->nb_sectors -= acb->n; acb->sector_num += acb->n; acb->buf += acb->n * 512; @@ -1174,23 +1358,22 @@ static void qcow_aio_write_cb(void *opaque, int ret) } index_in_cluster = acb->sector_num & (s->cluster_sectors - 1); - acb->n = s->cluster_sectors - index_in_cluster; - if (acb->n > acb->nb_sectors) - acb->n = acb->nb_sectors; - cluster_offset = alloc_cluster_offset(bs, acb->sector_num << 9, + n_end = index_in_cluster + acb->nb_sectors; + if (s->crypt_method && + n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) + n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors; + + acb->cluster_offset = alloc_cluster_offset(bs, acb->sector_num << 9, index_in_cluster, - index_in_cluster + acb->n); - if (!cluster_offset || (cluster_offset & 511) != 0) { + n_end, &acb->n, &acb->l2meta); + if (!acb->cluster_offset || (acb->cluster_offset & 511) != 0) { ret = -EIO; goto fail; } if (s->crypt_method) { if (!acb->cluster_data) { - acb->cluster_data = qemu_mallocz(s->cluster_size); - if (!acb->cluster_data) { - ret = -ENOMEM; - goto fail; - } + acb->cluster_data = qemu_mallocz(QCOW_MAX_CRYPT_CLUSTERS * + s->cluster_size); } encrypt_sectors(s, acb->sector_num, acb->cluster_data, acb->buf, acb->n, 1, &s->aes_encrypt_key); @@ -1199,7 +1382,7 @@ static void qcow_aio_write_cb(void *opaque, int ret) src_buf = acb->buf; } acb->hd_aiocb = bdrv_aio_write(s->hd, - (cluster_offset >> 9) + index_in_cluster, + (acb->cluster_offset >> 9) + index_in_cluster, src_buf, acb->n, qcow_aio_write_cb, acb); if (acb->hd_aiocb == NULL) @@ -1315,11 +1498,7 @@ static int qcow_create(const char *filename, int64_t total_size, offset += align_offset(l1_size * sizeof(uint64_t), s->cluster_size); s->refcount_table = qemu_mallocz(s->cluster_size); - if (!s->refcount_table) - goto fail; s->refcount_block = qemu_mallocz(s->cluster_size); - if (!s->refcount_block) - goto fail; s->refcount_table_offset = offset; header.refcount_table_offset = cpu_to_be64(offset); @@ -1356,11 +1535,6 @@ static int qcow_create(const char *filename, int64_t total_size, qemu_free(s->refcount_block); close(fd); return 0; - fail: - qemu_free(s->refcount_table); - qemu_free(s->refcount_block); - close(fd); - return -ENOMEM; } static int qcow_make_empty(BlockDriverState *bs) @@ -1373,7 +1547,7 @@ static int qcow_make_empty(BlockDriverState *bs) memset(s->l1_table, 0, l1_length); if (bdrv_pwrite(s->hd, s->l1_table_offset, s->l1_table, l1_length) < 0) - return -1; + return -1; ret = bdrv_truncate(s->hd, s->l1_table_offset + l1_length); if (ret < 0) return ret; @@ -1407,8 +1581,6 @@ static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num, return -EINVAL; out_buf = qemu_malloc(s->cluster_size + (s->cluster_size / 1000) + 128); - if (!out_buf) - return -ENOMEM; /* best compression, small window, no zlib header */ memset(&strm, 0, sizeof(strm)); @@ -1491,8 +1663,6 @@ static int update_snapshot_refcount(BlockDriverState *bs, l1_allocated = 0; if (l1_table_offset != s->l1_table_offset) { l1_table = qemu_malloc(l1_size2); - if (!l1_table) - goto fail; l1_allocated = 1; if (bdrv_pread(s->hd, l1_table_offset, l1_table, l1_size2) != l1_size2) @@ -1507,8 +1677,6 @@ static int update_snapshot_refcount(BlockDriverState *bs, l2_size = s->l2_size * sizeof(uint64_t); l2_table = qemu_malloc(l2_size); - if (!l2_table) - goto fail; l1_modified = 0; for(i = 0; i < l1_size; i++) { l2_offset = l1_table[i]; @@ -1611,10 +1779,14 @@ static int qcow_read_snapshots(BlockDriverState *bs) int64_t offset; uint32_t extra_data_size; + if (!s->nb_snapshots) { + s->snapshots = NULL; + s->snapshots_size = 0; + return 0; + } + offset = s->snapshots_offset; s->snapshots = qemu_mallocz(s->nb_snapshots * sizeof(QCowSnapshot)); - if (!s->snapshots) - goto fail; for(i = 0; i < s->nb_snapshots; i++) { offset = align_offset(offset, 8); if (bdrv_pread(s->hd, offset, &h, sizeof(h)) != sizeof(h)) @@ -1635,16 +1807,12 @@ static int qcow_read_snapshots(BlockDriverState *bs) offset += extra_data_size; sn->id_str = qemu_malloc(id_str_size + 1); - if (!sn->id_str) - goto fail; if (bdrv_pread(s->hd, offset, sn->id_str, id_str_size) != id_str_size) goto fail; offset += id_str_size; sn->id_str[id_str_size] = '\0'; sn->name = qemu_malloc(name_size + 1); - if (!sn->name) - goto fail; if (bdrv_pread(s->hd, offset, sn->name, name_size) != name_size) goto fail; offset += name_size; @@ -1810,8 +1978,6 @@ static int qcow_snapshot_create(BlockDriverState *bs, sn->l1_size = s->l1_size; l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t)); - if (!l1_table) - goto fail; for(i = 0; i < s->l1_size; i++) { l1_table[i] = cpu_to_be64(s->l1_table[i]); } @@ -1823,9 +1989,10 @@ static int qcow_snapshot_create(BlockDriverState *bs, l1_table = NULL; snapshots1 = qemu_malloc((s->nb_snapshots + 1) * sizeof(QCowSnapshot)); - if (!snapshots1) - goto fail; - memcpy(snapshots1, s->snapshots, s->nb_snapshots * sizeof(QCowSnapshot)); + if (s->snapshots) { + memcpy(snapshots1, s->snapshots, s->nb_snapshots * sizeof(QCowSnapshot)); + qemu_free(s->snapshots); + } s->snapshots = snapshots1; s->snapshots[s->nb_snapshots++] = *sn; @@ -1928,8 +2095,6 @@ static int qcow_snapshot_list(BlockDriverState *bs, int i; sn_tab = qemu_mallocz(s->nb_snapshots * sizeof(QEMUSnapshotInfo)); - if (!sn_tab) - goto fail; for(i = 0; i < s->nb_snapshots; i++) { sn_info = sn_tab + i; sn = s->snapshots + i; @@ -1944,10 +2109,6 @@ static int qcow_snapshot_list(BlockDriverState *bs, } *psn_tab = sn_tab; return s->nb_snapshots; - fail: - qemu_free(sn_tab); - *psn_tab = NULL; - return -ENOMEM; } /*********************************************************/ @@ -1959,12 +2120,8 @@ static int refcount_init(BlockDriverState *bs) int ret, refcount_table_size2, i; s->refcount_block_cache = qemu_malloc(s->cluster_size); - if (!s->refcount_block_cache) - goto fail; refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t); s->refcount_table = qemu_malloc(refcount_table_size2); - if (!s->refcount_table) - goto fail; if (s->refcount_table_size > 0) { ret = bdrv_pread(s->hd, s->refcount_table_offset, s->refcount_table, refcount_table_size2); @@ -2027,26 +2184,19 @@ static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size) BDRVQcowState *s = bs->opaque; int i, nb_clusters; - nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits; - for(;;) { - if (get_refcount(bs, s->free_cluster_index) == 0) { - s->free_cluster_index++; - for(i = 1; i < nb_clusters; i++) { - if (get_refcount(bs, s->free_cluster_index) != 0) - goto not_found; - s->free_cluster_index++; - } + nb_clusters = size_to_clusters(s, size); +retry: + for(i = 0; i < nb_clusters; i++) { + int64_t i = s->free_cluster_index++; + if (get_refcount(bs, i) != 0) + goto retry; + } #ifdef DEBUG_ALLOC2 - printf("alloc_clusters: size=%lld -> %lld\n", - size, - (s->free_cluster_index - nb_clusters) << s->cluster_bits); + printf("alloc_clusters: size=%lld -> %lld\n", + size, + (s->free_cluster_index - nb_clusters) << s->cluster_bits); #endif - return (s->free_cluster_index - nb_clusters) << s->cluster_bits; - } else { - not_found: - s->free_cluster_index++; - } - } + return (s->free_cluster_index - nb_clusters) << s->cluster_bits; } static int64_t alloc_clusters(BlockDriverState *bs, int64_t size) @@ -2110,8 +2260,7 @@ static int grow_refcount_table(BlockDriverState *bs, int min_size) int new_table_size, new_table_size2, refcount_table_clusters, i, ret; uint64_t *new_table; int64_t table_offset; - uint64_t data64; - uint32_t data32; + uint8_t data[12]; int old_table_size; int64_t old_table_offset; @@ -2136,8 +2285,6 @@ static int grow_refcount_table(BlockDriverState *bs, int min_size) #endif new_table_size2 = new_table_size * sizeof(uint64_t); new_table = qemu_mallocz(new_table_size2); - if (!new_table) - return -ENOMEM; memcpy(new_table, s->refcount_table, s->refcount_table_size * sizeof(uint64_t)); for(i = 0; i < s->refcount_table_size; i++) @@ -2150,13 +2297,10 @@ static int grow_refcount_table(BlockDriverState *bs, int min_size) for(i = 0; i < s->refcount_table_size; i++) be64_to_cpus(&new_table[i]); - data64 = cpu_to_be64(table_offset); + cpu_to_be64w((uint64_t*)data, table_offset); + cpu_to_be32w((uint32_t*)(data + 8), refcount_table_clusters); if (bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_offset), - &data64, sizeof(data64)) != sizeof(data64)) - goto fail; - data32 = cpu_to_be32(refcount_table_clusters); - if (bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_clusters), - &data32, sizeof(data32)) != sizeof(data32)) + data, sizeof(data)) != sizeof(data)) goto fail; qemu_free(s->refcount_table); old_table_offset = s->refcount_table_offset; @@ -2305,8 +2449,6 @@ static int check_refcounts_l1(BlockDriverState *bs, l1_table_offset, l1_size2); l1_table = qemu_malloc(l1_size2); - if (!l1_table) - goto fail; if (bdrv_pread(s->hd, l1_table_offset, l1_table, l1_size2) != l1_size2) goto fail; @@ -2315,8 +2457,6 @@ static int check_refcounts_l1(BlockDriverState *bs, l2_size = s->l2_size * sizeof(uint64_t); l2_table = qemu_malloc(l2_size); - if (!l2_table) - goto fail; for(i = 0; i < l1_size; i++) { l2_offset = l1_table[i]; if (l2_offset) { @@ -2385,7 +2525,7 @@ static void check_refcounts(BlockDriverState *bs) uint16_t *refcount_table; size = bdrv_getlength(s->hd); - nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits; + nb_clusters = size_to_clusters(s, size); refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t)); /* header */ @@ -2437,7 +2577,7 @@ static void dump_refcounts(BlockDriverState *bs) int refcount; size = bdrv_getlength(s->hd); - nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits; + nb_clusters = size_to_clusters(s, size); for(k = 0; k < nb_clusters;) { k1 = k; refcount = get_refcount(bs, k); @@ -2451,28 +2591,26 @@ static void dump_refcounts(BlockDriverState *bs) #endif BlockDriver bdrv_qcow2 = { - "qcow2", - sizeof(BDRVQcowState), - qcow_probe, - qcow_open, - NULL, - NULL, - qcow_close, - qcow_create, - qcow_flush, - qcow_is_allocated, - qcow_set_key, - qcow_make_empty, - - .bdrv_aio_read = qcow_aio_read, - .bdrv_aio_write = qcow_aio_write, - .bdrv_aio_cancel = qcow_aio_cancel, - .aiocb_size = sizeof(QCowAIOCB), + .format_name = "qcow2", + .instance_size = sizeof(BDRVQcowState), + .bdrv_probe = qcow_probe, + .bdrv_open = qcow_open, + .bdrv_close = qcow_close, + .bdrv_create = qcow_create, + .bdrv_flush = qcow_flush, + .bdrv_is_allocated = qcow_is_allocated, + .bdrv_set_key = qcow_set_key, + .bdrv_make_empty = qcow_make_empty, + + .bdrv_aio_read = qcow_aio_read, + .bdrv_aio_write = qcow_aio_write, + .bdrv_aio_cancel = qcow_aio_cancel, + .aiocb_size = sizeof(QCowAIOCB), .bdrv_write_compressed = qcow_write_compressed, .bdrv_snapshot_create = qcow_snapshot_create, - .bdrv_snapshot_goto = qcow_snapshot_goto, + .bdrv_snapshot_goto = qcow_snapshot_goto, .bdrv_snapshot_delete = qcow_snapshot_delete, - .bdrv_snapshot_list = qcow_snapshot_list, - .bdrv_get_info = qcow_get_info, + .bdrv_snapshot_list = qcow_snapshot_list, + .bdrv_get_info = qcow_get_info, };