lkml.org 
[lkml]   [2023]   [Jun]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/2] erofs: simplify z_erofs_transform_plain()
Date
Use memcpy_to_page() instead of open-coding them.

In addition, add a missing flush_dcache_page() even though almost all
modern architectures clear `PG_dcache_clean` flag for new file cache
pages so that it doesn't change anything in practice.

Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
---
preliminary tested with silesia dataset.

fs/erofs/decompressor.c | 19 ++++++++-----------
1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index ad53cf52d899..cfad1eac7fd9 100644
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -328,7 +328,7 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
const unsigned int lefthalf = rq->outputsize - righthalf;
const unsigned int interlaced_offset =
rq->alg == Z_EROFS_COMPRESSION_SHIFTED ? 0 : rq->pageofs_out;
- unsigned char *src, *dst;
+ u8 *src;

if (outpages > 2 && rq->alg == Z_EROFS_COMPRESSION_SHIFTED) {
DBG_BUGON(1);
@@ -341,22 +341,19 @@ static int z_erofs_transform_plain(struct z_erofs_decompress_req *rq,
}

src = kmap_local_page(rq->in[inpages - 1]) + rq->pageofs_in;
- if (rq->out[0]) {
- dst = kmap_local_page(rq->out[0]);
- memcpy(dst + rq->pageofs_out, src + interlaced_offset,
- righthalf);
- kunmap_local(dst);
- }
+ if (rq->out[0])
+ memcpy_to_page(rq->out[0], rq->pageofs_out,
+ src + interlaced_offset, righthalf);

if (outpages > inpages) {
DBG_BUGON(!rq->out[outpages - 1]);
if (rq->out[outpages - 1] != rq->in[inpages - 1]) {
- dst = kmap_local_page(rq->out[outpages - 1]);
- memcpy(dst, interlaced_offset ? src :
- (src + righthalf), lefthalf);
- kunmap_local(dst);
+ memcpy_to_page(rq->out[outpages - 1], 0, src +
+ (interlaced_offset ? 0 : righthalf),
+ lefthalf);
} else if (!interlaced_offset) {
memmove(src, src + righthalf, lefthalf);
+ flush_dcache_page(rq->in[inpages - 1]);
}
}
kunmap_local(src);
--
2.24.4
\
 
 \ /
  Last update: 2023-06-27 18:13    [W:0.716 / U:0.012 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site