diff options
author | Kent Overstreet <kent.overstreet@gmail.com> | 2017-01-08 00:13:18 -0900 |
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committer | Kent Overstreet <kent.overstreet@gmail.com> | 2017-01-20 09:07:08 -0900 |
commit | b33fc8298f7e13226b9895abc57c9bfce5e3fa2d (patch) | |
tree | a3d2a5a909b6372f7777c1c5c18cef5f81d123a9 /include/linux/lz4.h | |
parent | 7f4191a202ea4558ca2d5eb8a47daea33c9999c7 (diff) |
bcache in userspace; userspace fsck
Diffstat (limited to 'include/linux/lz4.h')
-rw-r--r-- | include/linux/lz4.h | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/include/linux/lz4.h b/include/linux/lz4.h new file mode 100644 index 00000000..6b784c59 --- /dev/null +++ b/include/linux/lz4.h @@ -0,0 +1,87 @@ +#ifndef __LZ4_H__ +#define __LZ4_H__ +/* + * LZ4 Kernel Interface + * + * Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#define LZ4_MEM_COMPRESS (16384) +#define LZ4HC_MEM_COMPRESS (262144 + (2 * sizeof(unsigned char *))) + +/* + * lz4_compressbound() + * Provides the maximum size that LZ4 may output in a "worst case" scenario + * (input data not compressible) + */ +static inline size_t lz4_compressbound(size_t isize) +{ + return isize + (isize / 255) + 16; +} + +/* + * lz4_compress() + * src : source address of the original data + * src_len : size of the original data + * dst : output buffer address of the compressed data + * This requires 'dst' of size LZ4_COMPRESSBOUND. + * dst_len : is the output size, which is returned after compress done + * workmem : address of the working memory. + * This requires 'workmem' of size LZ4_MEM_COMPRESS. + * return : Success if return 0 + * Error if return (< 0) + * note : Destination buffer and workmem must be already allocated with + * the defined size. + */ +int lz4_compress(const unsigned char *src, size_t src_len, + unsigned char *dst, size_t *dst_len, void *wrkmem); + + /* + * lz4hc_compress() + * src : source address of the original data + * src_len : size of the original data + * dst : output buffer address of the compressed data + * This requires 'dst' of size LZ4_COMPRESSBOUND. + * dst_len : is the output size, which is returned after compress done + * workmem : address of the working memory. + * This requires 'workmem' of size LZ4HC_MEM_COMPRESS. + * return : Success if return 0 + * Error if return (< 0) + * note : Destination buffer and workmem must be already allocated with + * the defined size. + */ +int lz4hc_compress(const unsigned char *src, size_t src_len, + unsigned char *dst, size_t *dst_len, void *wrkmem); + +/* + * lz4_decompress() + * src : source address of the compressed data + * src_len : is the input size, whcih is returned after decompress done + * dest : output buffer address of the decompressed data + * actual_dest_len: is the size of uncompressed data, supposing it's known + * return : Success if return 0 + * Error if return (< 0) + * note : Destination buffer must be already allocated. + * slightly faster than lz4_decompress_unknownoutputsize() + */ +int lz4_decompress(const unsigned char *src, size_t *src_len, + unsigned char *dest, size_t actual_dest_len); + +/* + * lz4_decompress_unknownoutputsize() + * src : source address of the compressed data + * src_len : is the input size, therefore the compressed size + * dest : output buffer address of the decompressed data + * dest_len: is the max size of the destination buffer, which is + * returned with actual size of decompressed data after + * decompress done + * return : Success if return 0 + * Error if return (< 0) + * note : Destination buffer must be already allocated. + */ +int lz4_decompress_unknownoutputsize(const unsigned char *src, size_t src_len, + unsigned char *dest, size_t *dest_len); +#endif |