[PATCH 2/3 v2] btrfs: reduce arguments for decompress_bio ops

[Anand Jain <anand.jain@oracle.com>]

struct compressed_bio pointer can be used instead.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
---
v2: added this patch
 fs/btrfs/compression.c | 43 +------------------------------------------
 fs/btrfs/compression.h | 44 ++++++++++++++++++++++++++++++++++++++++----
 fs/btrfs/lzo.c         | 10 +++++-----
 fs/btrfs/zlib.c        |  9 +++++----
 4 files changed, 51 insertions(+), 55 deletions(-)

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index ee934e612f15..e426a8f427b5 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -42,45 +42,6 @@
 #include "extent_io.h"
 #include "extent_map.h"
 
-struct compressed_bio {
-	/* number of bios pending for this compressed extent */
-	refcount_t pending_bios;
-
-	/* the pages with the compressed data on them */
-	struct page **compressed_pages;
-
-	/* inode that owns this data */
-	struct inode *inode;
-
-	/* starting offset in the inode for our pages */
-	u64 start;
-
-	/* number of bytes in the inode we're working on */
-	unsigned long len;
-
-	/* number of bytes on disk */
-	unsigned long compressed_len;
-
-	/* the compression algorithm for this bio */
-	int compress_type;
-
-	/* number of compressed pages in the array */
-	unsigned long nr_pages;
-
-	/* IO errors */
-	int errors;
-	int mirror_num;
-
-	/* for reads, this is the bio we are copying the data into */
-	struct bio *orig_bio;
-
-	/*
-	 * the start of a variable length array of checksums only
-	 * used by reads
-	 */
-	u32 sums;
-};
-
 static int btrfs_decompress_bio(struct compressed_bio *cb);
 
 static inline int compressed_bio_size(struct btrfs_fs_info *fs_info,
@@ -964,9 +925,7 @@ static int btrfs_decompress_bio(struct compressed_bio *cb)
 
 	workspace = find_workspace(type);
 
-	ret = btrfs_compress_op[type-1]->decompress_bio(workspace,
-			cb->compressed_pages, cb->start, cb->orig_bio,
-			cb->compressed_len);
+	ret = btrfs_compress_op[type-1]->decompress_bio(workspace, cb);
 
 	free_workspace(type, workspace);
 	return ret;
diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h
index 39ec43ab8df1..89bcf975efb8 100644
--- a/fs/btrfs/compression.h
+++ b/fs/btrfs/compression.h
@@ -34,6 +34,45 @@
 /* Maximum size of data before compression */
 #define BTRFS_MAX_UNCOMPRESSED		(SZ_128K)
 
+struct compressed_bio {
+	/* number of bios pending for this compressed extent */
+	refcount_t pending_bios;
+
+	/* the pages with the compressed data on them */
+	struct page **compressed_pages;
+
+	/* inode that owns this data */
+	struct inode *inode;
+
+	/* starting offset in the inode for our pages */
+	u64 start;
+
+	/* number of bytes in the inode we're working on */
+	unsigned long len;
+
+	/* number of bytes on disk */
+	unsigned long compressed_len;
+
+	/* the compression algorithm for this bio */
+	int compress_type;
+
+	/* number of compressed pages in the array */
+	unsigned long nr_pages;
+
+	/* IO errors */
+	int errors;
+	int mirror_num;
+
+	/* for reads, this is the bio we are copying the data into */
+	struct bio *orig_bio;
+
+	/*
+	 * the start of a variable length array of checksums only
+	 * used by reads
+	 */
+	u32 sums;
+};
+
 void btrfs_init_compress(void);
 void btrfs_exit_compress(void);
 
@@ -78,10 +117,7 @@ struct btrfs_compress_op {
 			      unsigned long *total_out);
 
 	int (*decompress_bio)(struct list_head *workspace,
-				 struct page **pages_in,
-				 u64 disk_start,
-				 struct bio *orig_bio,
-				 size_t srclen);
+				struct compressed_bio *cb);
 
 	int (*decompress)(struct list_head *workspace,
 			  unsigned char *data_in,
diff --git a/fs/btrfs/lzo.c b/fs/btrfs/lzo.c
index f48c8c14dc14..29b2e1319e6e 100644
--- a/fs/btrfs/lzo.c
+++ b/fs/btrfs/lzo.c
@@ -254,16 +254,13 @@ static int lzo_compress_pages(struct list_head *ws,
 	return ret;
 }
 
-static int lzo_decompress_bio(struct list_head *ws,
-				 struct page **pages_in,
-				 u64 disk_start,
-				 struct bio *orig_bio,
-				 size_t srclen)
+static int lzo_decompress_bio(struct list_head *ws, struct compressed_bio *cb)
 {
 	struct workspace *workspace = list_entry(ws, struct workspace, list);
 	int ret = 0, ret2;
 	char *data_in;
 	unsigned long page_in_index = 0;
+	size_t srclen = cb->compressed_len;
 	unsigned long total_pages_in = DIV_ROUND_UP(srclen, PAGE_SIZE);
 	unsigned long buf_start;
 	unsigned long buf_offset = 0;
@@ -278,6 +275,9 @@ static int lzo_decompress_bio(struct list_head *ws,
 	unsigned long tot_len;
 	char *buf;
 	bool may_late_unmap, need_unmap;
+	struct page **pages_in = cb->compressed_pages;
+	u64 disk_start = cb->start;
+	struct bio *orig_bio = cb->orig_bio;
 
 	data_in = kmap(pages_in[0]);
 	tot_len = read_compress_length(data_in);
diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c
index 135b10823c6d..c0f592406bb1 100644
--- a/fs/btrfs/zlib.c
+++ b/fs/btrfs/zlib.c
@@ -211,10 +211,7 @@ static int zlib_compress_pages(struct list_head *ws,
 	return ret;
 }
 
-static int zlib_decompress_bio(struct list_head *ws, struct page **pages_in,
-				  u64 disk_start,
-				  struct bio *orig_bio,
-				  size_t srclen)
+static int zlib_decompress_bio(struct list_head *ws, struct compressed_bio *cb)
 {
 	struct workspace *workspace = list_entry(ws, struct workspace, list);
 	int ret = 0, ret2;
@@ -222,8 +219,12 @@ static int zlib_decompress_bio(struct list_head *ws, struct page **pages_in,
 	char *data_in;
 	size_t total_out = 0;
 	unsigned long page_in_index = 0;
+	size_t srclen = cb->compressed_len;
 	unsigned long total_pages_in = DIV_ROUND_UP(srclen, PAGE_SIZE);
 	unsigned long buf_start;
+	struct page **pages_in = cb->compressed_pages;
+	u64 disk_start = cb->start;
+	struct bio *orig_bio = cb->orig_bio;
 
 	data_in = kmap(pages_in[page_in_index]);
 	workspace->strm.next_in = data_in;
-- 
2.10.0