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e02d238c98
Do not __GFP_ZERO allocated zcomp ->private pages. We keep allocated streams around and use them for read/write requests, so we supply a zeroed out ->private to compression algorithm as a scratch buffer only once -- the first time we use that stream. For the rest of IO requests served by this stream ->private usually contains some temporarily data from the previous requests. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
57 lines
1.3 KiB
C
57 lines
1.3 KiB
C
/*
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* Copyright (C) 2014 Sergey Senozhatsky.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/lz4.h>
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#include <linux/vmalloc.h>
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#include <linux/mm.h>
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#include "zcomp_lz4.h"
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static void *zcomp_lz4_create(gfp_t flags)
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{
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void *ret;
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ret = kmalloc(LZ4_MEM_COMPRESS, flags);
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if (!ret)
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ret = __vmalloc(LZ4_MEM_COMPRESS,
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flags | __GFP_HIGHMEM,
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PAGE_KERNEL);
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return ret;
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}
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static void zcomp_lz4_destroy(void *private)
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{
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kvfree(private);
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}
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static int zcomp_lz4_compress(const unsigned char *src, unsigned char *dst,
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size_t *dst_len, void *private)
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{
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/* return : Success if return 0 */
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return lz4_compress(src, PAGE_SIZE, dst, dst_len, private);
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}
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static int zcomp_lz4_decompress(const unsigned char *src, size_t src_len,
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unsigned char *dst)
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{
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size_t dst_len = PAGE_SIZE;
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/* return : Success if return 0 */
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return lz4_decompress_unknownoutputsize(src, src_len, dst, &dst_len);
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}
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struct zcomp_backend zcomp_lz4 = {
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.compress = zcomp_lz4_compress,
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.decompress = zcomp_lz4_decompress,
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.create = zcomp_lz4_create,
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.destroy = zcomp_lz4_destroy,
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.name = "lz4",
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};
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