diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/qcow2-cluster.c | 70 | ||||
| -rw-r--r-- | block/qcow2.c | 71 |
2 files changed, 71 insertions, 70 deletions
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index d37fe08b3d..e2737429f5 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1571,76 +1571,6 @@ again: return 0; } -static int decompress_buffer(uint8_t *out_buf, int out_buf_size, - const uint8_t *buf, int buf_size) -{ - z_stream strm1, *strm = &strm1; - int ret, out_len; - - memset(strm, 0, sizeof(*strm)); - - strm->next_in = (uint8_t *)buf; - strm->avail_in = buf_size; - strm->next_out = out_buf; - strm->avail_out = out_buf_size; - - ret = inflateInit2(strm, -12); - if (ret != Z_OK) - return -1; - ret = inflate(strm, Z_FINISH); - out_len = strm->next_out - out_buf; - if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) || - out_len != out_buf_size) { - inflateEnd(strm); - return -1; - } - inflateEnd(strm); - return 0; -} - -int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset) -{ - BDRVQcow2State *s = bs->opaque; - int ret, csize, nb_csectors, sector_offset; - uint64_t coffset; - - coffset = cluster_offset & s->cluster_offset_mask; - if (s->cluster_cache_offset != coffset) { - nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1; - sector_offset = coffset & 511; - csize = nb_csectors * 512 - sector_offset; - - /* Allocate buffers on first decompress operation, most images are - * uncompressed and the memory overhead can be avoided. The buffers - * are freed in .bdrv_close(). - */ - if (!s->cluster_data) { - /* one more sector for decompressed data alignment */ - s->cluster_data = qemu_try_blockalign(bs->file->bs, - QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size + 512); - if (!s->cluster_data) { - return -ENOMEM; - } - } - if (!s->cluster_cache) { - s->cluster_cache = g_malloc(s->cluster_size); - } - - BLKDBG_EVENT(bs->file, BLKDBG_READ_COMPRESSED); - ret = bdrv_read(bs->file, coffset >> 9, s->cluster_data, - nb_csectors); - if (ret < 0) { - return ret; - } - if (decompress_buffer(s->cluster_cache, s->cluster_size, - s->cluster_data + sector_offset, csize) < 0) { - return -EIO; - } - s->cluster_cache_offset = coffset; - } - return 0; -} - /* * This discards as many clusters of nb_clusters as possible at once (i.e. * all clusters in the same L2 slice) and returns the number of discarded diff --git a/block/qcow2.c b/block/qcow2.c index 8606588aca..a3b9fe391c 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -3762,6 +3762,34 @@ static ssize_t qcow2_compress(void *dest, size_t dest_size, return ret; } +static int decompress_buffer(uint8_t *out_buf, int out_buf_size, + const uint8_t *buf, int buf_size) +{ + z_stream strm1, *strm = &strm1; + int ret, out_len; + + memset(strm, 0, sizeof(*strm)); + + strm->next_in = (uint8_t *)buf; + strm->avail_in = buf_size; + strm->next_out = out_buf; + strm->avail_out = out_buf_size; + + ret = inflateInit2(strm, -12); + if (ret != Z_OK) { + return -1; + } + ret = inflate(strm, Z_FINISH); + out_len = strm->next_out - out_buf; + if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) || + out_len != out_buf_size) { + inflateEnd(strm); + return -1; + } + inflateEnd(strm); + return 0; +} + #define MAX_COMPRESS_THREADS 4 typedef struct Qcow2CompressData { @@ -3915,6 +3943,49 @@ fail: return ret; } +int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset) +{ + BDRVQcow2State *s = bs->opaque; + int ret, csize, nb_csectors, sector_offset; + uint64_t coffset; + + coffset = cluster_offset & s->cluster_offset_mask; + if (s->cluster_cache_offset != coffset) { + nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1; + sector_offset = coffset & 511; + csize = nb_csectors * 512 - sector_offset; + + /* Allocate buffers on first decompress operation, most images are + * uncompressed and the memory overhead can be avoided. The buffers + * are freed in .bdrv_close(). + */ + if (!s->cluster_data) { + /* one more sector for decompressed data alignment */ + s->cluster_data = qemu_try_blockalign(bs->file->bs, + QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size + 512); + if (!s->cluster_data) { + return -ENOMEM; + } + } + if (!s->cluster_cache) { + s->cluster_cache = g_malloc(s->cluster_size); + } + + BLKDBG_EVENT(bs->file, BLKDBG_READ_COMPRESSED); + ret = bdrv_read(bs->file, coffset >> 9, s->cluster_data, + nb_csectors); + if (ret < 0) { + return ret; + } + if (decompress_buffer(s->cluster_cache, s->cluster_size, + s->cluster_data + sector_offset, csize) < 0) { + return -EIO; + } + s->cluster_cache_offset = coffset; + } + return 0; +} + static int make_completely_empty(BlockDriverState *bs) { BDRVQcow2State *s = bs->opaque; |