btrfs: allow to set compression level for zlib
Preliminary support for setting compression level for zlib, the
following works:
$ mount -o compess=zlib # default
$ mount -o compess=zlib0 # same
$ mount -o compess=zlib9 # level 9, slower sync, less data
$ mount -o compess=zlib1 # level 1, faster sync, more data
$ mount -o remount,compress=zlib3 # level set by remount
The compress-force works the same as compress'. The level is visible in
the same format in /proc/mounts. Level set via file property does not
work yet.
Required patch: "btrfs: prepare for extensions in compression options"
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h
index d2781ff..da20755 100644
--- a/fs/btrfs/compression.h
+++ b/fs/btrfs/compression.h
@@ -76,7 +76,7 @@ struct compressed_bio {
void btrfs_init_compress(void);
void btrfs_exit_compress(void);
-int btrfs_compress_pages(int type, struct address_space *mapping,
+int btrfs_compress_pages(unsigned int type_level, struct address_space *mapping,
u64 start, struct page **pages,
unsigned long *out_pages,
unsigned long *total_in,
@@ -95,6 +95,8 @@ blk_status_t btrfs_submit_compressed_write(struct inode *inode, u64 start,
blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
int mirror_num, unsigned long bio_flags);
+unsigned btrfs_compress_str2level(const char *str);
+
enum btrfs_compression_type {
BTRFS_COMPRESS_NONE = 0,
BTRFS_COMPRESS_ZLIB = 1,
@@ -124,6 +126,8 @@ struct btrfs_compress_op {
struct page *dest_page,
unsigned long start_byte,
size_t srclen, size_t destlen);
+
+ void (*set_level)(struct list_head *ws, unsigned int type);
};
extern const struct btrfs_compress_op btrfs_zlib_compress;