diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/erofs/Kconfig | 15 | ||||
| -rw-r--r-- | fs/erofs/decompress.c | 83 | ||||
| -rw-r--r-- | fs/erofs/erofs_fs.h | 1 |
3 files changed, 99 insertions, 0 deletions
diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig index ee4e777c5c8..c8463357ca2 100644 --- a/fs/erofs/Kconfig +++ b/fs/erofs/Kconfig @@ -19,3 +19,18 @@ config FS_EROFS_ZIP help Enable fixed-sized output compression for EROFS. If you don't want to enable compression feature, say N. + +config FS_EROFS_ZIP_DEFLATE + bool "EROFS DEFLATE compressed data support" + depends on FS_EROFS_ZIP + select ZLIB + help + Saying Y here includes support for reading EROFS file systems + containing DEFLATE compressed data. It gives better compression + ratios than the default LZ4 format, while it costs more CPU + overhead. + + DEFLATE support is an experimental feature for now and so most + file systems will be readable without selecting this option. + + If unsure, say N. diff --git a/fs/erofs/decompress.c b/fs/erofs/decompress.c index e04e5c34a8d..ec74816534c 100644 --- a/fs/erofs/decompress.c +++ b/fs/erofs/decompress.c @@ -1,6 +1,85 @@ // SPDX-License-Identifier: GPL-2.0+ #include "decompress.h" +#if IS_ENABLED(CONFIG_ZLIB) +#include <u-boot/zlib.h> + +/* report a zlib or i/o error */ +static int zerr(int ret) +{ + switch (ret) { + case Z_STREAM_ERROR: + return -EINVAL; + case Z_DATA_ERROR: + return -EIO; + case Z_MEM_ERROR: + return -ENOMEM; + case Z_ERRNO: + default: + return -EFAULT; + } +} + +static int z_erofs_decompress_deflate(struct z_erofs_decompress_req *rq) +{ + u8 *dest = (u8 *)rq->out; + u8 *src = (u8 *)rq->in; + u8 *buff = NULL; + unsigned int inputmargin = 0; + z_stream strm; + int ret; + + while (!src[inputmargin & (erofs_blksiz() - 1)]) + if (!(++inputmargin & (erofs_blksiz() - 1))) + break; + + if (inputmargin >= rq->inputsize) + return -EFSCORRUPTED; + + if (rq->decodedskip) { + buff = malloc(rq->decodedlength); + if (!buff) + return -ENOMEM; + dest = buff; + } + + /* allocate inflate state */ + strm.zalloc = Z_NULL; + strm.zfree = Z_NULL; + strm.opaque = Z_NULL; + strm.avail_in = 0; + strm.next_in = Z_NULL; + ret = inflateInit2(&strm, -15); + if (ret != Z_OK) { + free(buff); + return zerr(ret); + } + + strm.next_in = src + inputmargin; + strm.avail_in = rq->inputsize - inputmargin; + strm.next_out = dest; + strm.avail_out = rq->decodedlength; + + ret = inflate(&strm, rq->partial_decoding ? Z_SYNC_FLUSH : Z_FINISH); + if (ret != Z_STREAM_END || strm.total_out != rq->decodedlength) { + if (ret != Z_OK || !rq->partial_decoding) { + ret = zerr(ret); + goto out_inflate_end; + } + } + + if (rq->decodedskip) + memcpy(rq->out, dest + rq->decodedskip, + rq->decodedlength - rq->decodedskip); + +out_inflate_end: + inflateEnd(&strm); + if (buff) + free(buff); + return ret; +} +#endif + #if IS_ENABLED(CONFIG_LZ4) #include <u-boot/lz4.h> static int z_erofs_decompress_lz4(struct z_erofs_decompress_req *rq) @@ -94,5 +173,9 @@ int z_erofs_decompress(struct z_erofs_decompress_req *rq) if (rq->alg == Z_EROFS_COMPRESSION_LZ4) return z_erofs_decompress_lz4(rq); #endif +#if IS_ENABLED(CONFIG_ZLIB) + if (rq->alg == Z_EROFS_COMPRESSION_DEFLATE) + return z_erofs_decompress_deflate(rq); +#endif return -EOPNOTSUPP; } diff --git a/fs/erofs/erofs_fs.h b/fs/erofs/erofs_fs.h index 158e2c68a1a..5bac4fe1a1d 100644 --- a/fs/erofs/erofs_fs.h +++ b/fs/erofs/erofs_fs.h @@ -304,6 +304,7 @@ enum { enum { Z_EROFS_COMPRESSION_LZ4 = 0, Z_EROFS_COMPRESSION_LZMA = 1, + Z_EROFS_COMPRESSION_DEFLATE = 2, Z_EROFS_COMPRESSION_MAX }; |