diff options
| -rw-r--r-- | fs/btrfs/compression.c | 23 | ||||
| -rw-r--r-- | fs/btrfs/compression.h | 2 | ||||
| -rw-r--r-- | fs/btrfs/zlib.c | 73 |
3 files changed, 36 insertions, 62 deletions
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index 193168214eeb..68345f73d429 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -141,16 +141,16 @@ static int compression_decompress_bio(struct list_head *ws, } static int compression_decompress(int type, struct list_head *ws, - const u8 *data_in, struct page *dest_page, - unsigned long start_byte, size_t srclen, size_t destlen) + const u8 *data_in, struct page *dest_page, + unsigned long dest_pgoff, size_t srclen, size_t destlen) { switch (type) { case BTRFS_COMPRESS_ZLIB: return zlib_decompress(ws, data_in, dest_page, - start_byte, srclen, destlen); + dest_pgoff, srclen, destlen); case BTRFS_COMPRESS_LZO: return lzo_decompress(ws, data_in, dest_page, - start_byte, srclen, destlen); + dest_pgoff, srclen, destlen); case BTRFS_COMPRESS_ZSTD: return zstd_decompress(ws, data_in, dest_page, - start_byte, srclen, destlen); + dest_pgoff, srclen, destlen); case BTRFS_COMPRESS_NONE: default: /* @@ -1037,14 +1037,23 @@ static int btrfs_decompress_bio(struct compressed_bio *cb) * start_byte tells us the offset into the compressed data we're interested in */ int btrfs_decompress(int type, const u8 *data_in, struct page *dest_page, - unsigned long start_byte, size_t srclen, size_t destlen) + unsigned long dest_pgoff, size_t srclen, size_t destlen) { + struct btrfs_fs_info *fs_info = btrfs_sb(dest_page->mapping->host->i_sb); struct list_head *workspace; + const u32 sectorsize = fs_info->sectorsize; int ret; + /* + * The full destination page range should not exceed the page size. + * And the @destlen should not exceed sectorsize, as this is only called for + * inline file extents, which should not exceed sectorsize. + */ + ASSERT(dest_pgoff + destlen <= PAGE_SIZE && destlen <= sectorsize); + workspace = get_workspace(type, 0); ret = compression_decompress(type, workspace, data_in, dest_page, - start_byte, srclen, destlen); + dest_pgoff, srclen, destlen); put_workspace(type, workspace); return ret; diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h index 93cc92974dee..2b4dfb1b010c 100644 --- a/fs/btrfs/compression.h +++ b/fs/btrfs/compression.h @@ -148,7 +148,7 @@ int zlib_compress_pages(struct list_head *ws, struct address_space *mapping, unsigned long *total_in, unsigned long *total_out); int zlib_decompress_bio(struct list_head *ws, struct compressed_bio *cb); int zlib_decompress(struct list_head *ws, const u8 *data_in, - struct page *dest_page, unsigned long start_byte, size_t srclen, + struct page *dest_page, unsigned long dest_pgoff, size_t srclen, size_t destlen); struct list_head *zlib_alloc_workspace(unsigned int level); void zlib_free_workspace(struct list_head *ws); diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c index 36cf1f0e338e..8da66ea699e8 100644 --- a/fs/btrfs/zlib.c +++ b/fs/btrfs/zlib.c @@ -354,18 +354,13 @@ done: } int zlib_decompress(struct list_head *ws, const u8 *data_in, - struct page *dest_page, unsigned long start_byte, size_t srclen, + struct page *dest_page, unsigned long dest_pgoff, size_t srclen, size_t destlen) { struct workspace *workspace = list_entry(ws, struct workspace, list); int ret = 0; int wbits = MAX_WBITS; - unsigned long bytes_left; - unsigned long total_out = 0; - unsigned long pg_offset = 0; - - destlen = min_t(unsigned long, destlen, PAGE_SIZE); - bytes_left = destlen; + unsigned long to_copy; workspace->strm.next_in = data_in; workspace->strm.avail_in = srclen; @@ -390,60 +385,30 @@ int zlib_decompress(struct list_head *ws, const u8 *data_in, return -EIO; } - while (bytes_left > 0) { - unsigned long buf_start; - unsigned long buf_offset; - unsigned long bytes; - - ret = zlib_inflate(&workspace->strm, Z_NO_FLUSH); - if (ret != Z_OK && ret != Z_STREAM_END) - break; - - buf_start = total_out; - total_out = workspace->strm.total_out; - - if (total_out == buf_start) { - ret = -EIO; - break; - } - - if (total_out <= start_byte) - goto next; - - if (total_out > start_byte && buf_start < start_byte) - buf_offset = start_byte - buf_start; - else - buf_offset = 0; - - bytes = min(PAGE_SIZE - pg_offset, - PAGE_SIZE - (buf_offset % PAGE_SIZE)); - bytes = min(bytes, bytes_left); + /* + * Everything (in/out buf) should be at most one sector, there should + * be no need to switch any input/output buffer. + */ + ret = zlib_inflate(&workspace->strm, Z_FINISH); + to_copy = min(workspace->strm.total_out, destlen); + if (ret != Z_STREAM_END) + goto out; - memcpy_to_page(dest_page, pg_offset, - workspace->buf + buf_offset, bytes); + memcpy_to_page(dest_page, dest_pgoff, workspace->buf, to_copy); - pg_offset += bytes; - bytes_left -= bytes; -next: - workspace->strm.next_out = workspace->buf; - workspace->strm.avail_out = workspace->buf_size; - } - - if (ret != Z_STREAM_END && bytes_left != 0) +out: + if (unlikely(to_copy != destlen)) { + pr_warn_ratelimited("BTRFS: infalte failed, decompressed=%lu expected=%zu\n", + to_copy, destlen); ret = -EIO; - else + } else { ret = 0; + } zlib_inflateEnd(&workspace->strm); - /* - * this should only happen if zlib returned fewer bytes than we - * expected. btrfs_get_block is responsible for zeroing from the - * end of the inline extent (destlen) to the end of the page - */ - if (pg_offset < destlen) { - memzero_page(dest_page, pg_offset, destlen - pg_offset); - } + if (unlikely(to_copy < destlen)) + memzero_page(dest_page, dest_pgoff + to_copy, destlen - to_copy); return ret; } |