f2fs: compress: add nocompress extensions support

When we create a directory with enable compression, all file write into
directory will try to compress.But sometimes we may know, new file
cannot meet compression ratio requirements.
We need a nocompress extension to skip those files to avoid unnecessary
compress page test.

After add nocompress_extension, the priority should be:
dir_flag < comp_extention,nocompress_extension < comp_file_flag,
no_comp_file_flag.

Priority in between FS_COMPR_FL, FS_NOCOMP_FS, extensions:
   * compress_extension=so; nocompress_extension=zip; chattr +c dir;
     touch dir/foo.so; touch dir/bar.zip; touch dir/baz.txt; then foo.so
     and baz.txt should be compresse, bar.zip should be non-compressed.
     chattr +c dir/bar.zip can enable compress on bar.zip.
   * compress_extension=so; nocompress_extension=zip; chattr -c dir;
     touch dir/foo.so; touch dir/bar.zip; touch dir/baz.txt; then foo.so
     should be compresse, bar.zip and baz.txt should be non-compressed.
     chattr+c dir/bar.zip; chattr+c dir/baz.txt; can enable compress on
     bar.zip and baz.txt.

Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 15 insertions, 5 deletions

diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index d4139e166b95..e149c8c66a71 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -287,14 +287,16 @@ static void set_compress_inode(struct f2fs_sb_info *sbi, struct inode *inode,
 						const unsigned char *name)
 {
 	__u8 (*extlist)[F2FS_EXTENSION_LEN] = sbi->raw_super->extension_list;
-	unsigned char (*ext)[F2FS_EXTENSION_LEN];
-	unsigned int ext_cnt = F2FS_OPTION(sbi).compress_ext_cnt;
+	unsigned char (*noext)[F2FS_EXTENSION_LEN] = F2FS_OPTION(sbi).noextensions;
+	unsigned char (*ext)[F2FS_EXTENSION_LEN] = F2FS_OPTION(sbi).extensions;
+	unsigned char ext_cnt = F2FS_OPTION(sbi).compress_ext_cnt;
+	unsigned char noext_cnt = F2FS_OPTION(sbi).nocompress_ext_cnt;
 	int i, cold_count, hot_count;
 
 	if (!f2fs_sb_has_compression(sbi) ||
-			is_inode_flag_set(inode, FI_COMPRESSED_FILE) ||
 			F2FS_I(inode)->i_flags & F2FS_NOCOMP_FL ||
-			!f2fs_may_compress(inode))
+			!f2fs_may_compress(inode) ||
+			(!ext_cnt && !noext_cnt))
 		return;
 
 	down_read(&sbi->sb_lock);
@@ -311,7 +313,15 @@ static void set_compress_inode(struct f2fs_sb_info *sbi, struct inode *inode,
 
 	up_read(&sbi->sb_lock);
 
-	ext = F2FS_OPTION(sbi).extensions;
+	for (i = 0; i < noext_cnt; i++) {
+		if (is_extension_exist(name, noext[i], false)) {
+			f2fs_disable_compressed_file(inode);
+			return;
+		}
+	}
+
+	if (is_inode_flag_set(inode, FI_COMPRESSED_FILE))
+		return;
 
 	for (i = 0; i < ext_cnt; i++) {
 		if (!is_extension_exist(name, ext[i], false))