[PATCH 1/3] squashfs: parametrize decompressors on buffer_head operations

From: Ferenc Wagner
Date: Tue Mar 30 2010 - 10:21:34 EST


---
fs/squashfs/block.c | 9 ++++++++-
fs/squashfs/decompressor.h | 8 +++++---
fs/squashfs/lzma_wrapper.c | 11 ++++++-----
fs/squashfs/zlib_wrapper.c | 13 +++++++------
4 files changed, 26 insertions(+), 15 deletions(-)

diff --git a/fs/squashfs/block.c b/fs/squashfs/block.c
index 6f9914d..c7e5881 100644
--- a/fs/squashfs/block.c
+++ b/fs/squashfs/block.c
@@ -37,6 +37,13 @@
#include "squashfs_fs_i.h"
#include "squashfs.h"
#include "decompressor.h"
+
+static int update_buffer(struct buffer_head *bh)
+{
+ wait_on_buffer(bh);
+ return buffer_uptodate(bh);
+}
+
/*
* Read the metadata block length, this is stored in the first two
* bytes of the metadata block.
@@ -152,7 +159,7 @@ int squashfs_read_data(struct super_block *sb, void **buffer, u64 index,

if (compressed) {
length = squashfs_decompress(msblk, buffer, bh, b, offset,
- length, srclength, pages);
+ length, srclength, pages, update_buffer, put_bh);
if (length < 0)
goto read_failure;
} else {
diff --git a/fs/squashfs/decompressor.h b/fs/squashfs/decompressor.h
index 7425f80..7de948b 100644
--- a/fs/squashfs/decompressor.h
+++ b/fs/squashfs/decompressor.h
@@ -27,7 +27,8 @@ struct squashfs_decompressor {
void *(*init)(struct squashfs_sb_info *);
void (*free)(void *);
int (*decompress)(struct squashfs_sb_info *, void **,
- struct buffer_head **, int, int, int, int, int);
+ struct buffer_head **, int, int, int, int, int,
+ int (*)(struct buffer_head *), void (*)(struct buffer_head *));
int id;
char *name;
int supported;
@@ -47,9 +48,10 @@ static inline void squashfs_decompressor_free(struct squashfs_sb_info *msblk,

static inline int squashfs_decompress(struct squashfs_sb_info *msblk,
void **buffer, struct buffer_head **bh, int b, int offset, int length,
- int srclength, int pages)
+ int srclength, int pages,
+ int (*update_buffer)(struct buffer_head *), void (*put_buffer)(struct buffer_head *))
{
return msblk->decompressor->decompress(msblk, buffer, bh, b, offset,
- length, srclength, pages);
+ length, srclength, pages, update_buffer, put_buffer);
}
#endif
diff --git a/fs/squashfs/lzma_wrapper.c b/fs/squashfs/lzma_wrapper.c
index 9fa617d..994c37e 100644
--- a/fs/squashfs/lzma_wrapper.c
+++ b/fs/squashfs/lzma_wrapper.c
@@ -88,7 +88,9 @@ static void lzma_free(void *strm)

static int lzma_uncompress(struct squashfs_sb_info *msblk, void **buffer,
struct buffer_head **bh, int b, int offset, int length, int srclength,
- int pages)
+ int pages,
+ int (*update_buffer)(struct buffer_head *),
+ void (*put_buffer)(struct buffer_head *))
{
struct squashfs_lzma *stream = msblk->stream;
void *buff = stream->input;
@@ -97,8 +99,7 @@ static int lzma_uncompress(struct squashfs_sb_info *msblk, void **buffer,
mutex_lock(&lzma_mutex);

for (i = 0; i < b; i++) {
- wait_on_buffer(bh[i]);
- if (!buffer_uptodate(bh[i]))
+ if (!update_buffer(bh[i]))
goto block_release;

avail = min(bytes, msblk->devblksize - offset);
@@ -106,7 +107,7 @@ static int lzma_uncompress(struct squashfs_sb_info *msblk, void **buffer,
buff += avail;
bytes -= avail;
offset = 0;
- put_bh(bh[i]);
+ put_buffer(bh[i]);
}

lzma_error = 0;
@@ -131,7 +132,7 @@ static int lzma_uncompress(struct squashfs_sb_info *msblk, void **buffer,

block_release:
for (; i < b; i++)
- put_bh(bh[i]);
+ put_buffer(bh[i]);

failed:
mutex_unlock(&lzma_mutex);
diff --git a/fs/squashfs/zlib_wrapper.c b/fs/squashfs/zlib_wrapper.c
index 4dd70e0..09cdcc1 100644
--- a/fs/squashfs/zlib_wrapper.c
+++ b/fs/squashfs/zlib_wrapper.c
@@ -63,7 +63,9 @@ static void zlib_free(void *strm)

static int zlib_uncompress(struct squashfs_sb_info *msblk, void **buffer,
struct buffer_head **bh, int b, int offset, int length, int srclength,
- int pages)
+ int pages,
+ int (*update_buffer)(struct buffer_head *),
+ void (*put_buffer)(struct buffer_head *))
{
int zlib_err = 0, zlib_init = 0;
int avail, bytes, k = 0, page = 0;
@@ -79,13 +81,12 @@ static int zlib_uncompress(struct squashfs_sb_info *msblk, void **buffer,
if (stream->avail_in == 0 && k < b) {
avail = min(bytes, msblk->devblksize - offset);
bytes -= avail;
- wait_on_buffer(bh[k]);
- if (!buffer_uptodate(bh[k]))
+ if (!update_buffer(bh[k]))
goto release_mutex;

if (avail == 0) {
offset = 0;
- put_bh(bh[k++]);
+ put_buffer(bh[k++]);
continue;
}

@@ -113,7 +114,7 @@ static int zlib_uncompress(struct squashfs_sb_info *msblk, void **buffer,
zlib_err = zlib_inflate(stream, Z_SYNC_FLUSH);

if (stream->avail_in == 0 && k < b)
- put_bh(bh[k++]);
+ put_buffer(bh[k++]);
} while (zlib_err == Z_OK);

if (zlib_err != Z_STREAM_END) {
@@ -134,7 +135,7 @@ release_mutex:
mutex_unlock(&msblk->read_data_mutex);

for (; k < b; k++)
- put_bh(bh[k]);
+ put_buffer(bh[k]);

return -EIO;
}
--
1.6.5

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