f2fs: support hot file extension
This patch supports to recognize hot file extension in f2fs, so that we
can allocate proper hot segment location for its data, which can lead to
better hot/cold seperation in filesystem.
In addition, we changes a bit on query/add/del operation method for
extension_list sysfs entry as below:
- Query: cat /sys/fs/f2fs/<disk>/extension_list
- Add: echo 'extension' > /sys/fs/f2fs/<disk>/extension_list
- Del: echo '!extension' > /sys/fs/f2fs/<disk>/extension_list
- Add: echo '[h/c]extension' > /sys/fs/f2fs/<disk>/extension_list
- Del: echo '[h/c]!extension' > /sys/fs/f2fs/<disk>/extension_list
- [h] means add/del hot file extension
- [c] means add/del cold file extension
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
index d8c2414..b06ab1f 100644
--- a/include/linux/f2fs_fs.h
+++ b/include/linux/f2fs_fs.h
@@ -111,7 +111,8 @@
__u8 encrypt_pw_salt[16]; /* Salt used for string2key algorithm */
struct f2fs_device devs[MAX_DEVICES]; /* device list */
__le32 qf_ino[F2FS_MAX_QUOTAS]; /* quota inode numbers */
- __u8 reserved[315]; /* valid reserved region */
+ __u8 hot_ext_count; /* # of hot file extension */
+ __u8 reserved[314]; /* valid reserved region */
} __packed;
/*