btrfs: reduce arguments for decompress_bio ops

struct compressed_bio pointer can be used instead.
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NNikolay Borisov <nborisov@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

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,
@@ -963,12 +924,9 @@ static int btrfs_decompress_bio(struct compressed_bio *cb)
 	int type = cb->compress_type;
 
 	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;
 }
 

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,

fs/btrfs/lzo.c

@@ -25,6 +25,7 @@
 #include <linux/pagemap.h>
 #include <linux/bio.h>
 #include <linux/lzo.h>
+#include <linux/refcount.h>
 #include "compression.h"
 
 #define LZO_LEN	4
@@ -254,16 +255,13 @@ 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 +276,9 @@ 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);

fs/btrfs/zlib.c

@@ -30,6 +30,7 @@
 #include <linux/sched.h>
 #include <linux/pagemap.h>
 #include <linux/bio.h>
+#include <linux/refcount.h>
 #include "compression.h"
 
 struct workspace {
@@ -211,10 +212,7 @@ 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 +220,12 @@ 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;