f2fs: add mount option for segment allocation policy
This patch adds an mount option, "alloc_mode=%s" having two options, "default"
and "reuse".
In "alloc_mode=reuse" case, f2fs starts to allocate segments from 0'th segment
all the time to reassign segments. It'd be useful for small-sized eMMC parts.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 3bb4e94..833c9bc 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1043,6 +1043,11 @@ enum {
WHINT_MODE_FS, /* pass down hints with F2FS policy */
};
+enum {
+ ALLOC_MODE_DEFAULT, /* stay default */
+ ALLOC_MODE_REUSE, /* reuse segments as much as possible */
+};
+
struct f2fs_sb_info {
struct super_block *sb; /* pointer to VFS super block */
struct proc_dir_entry *s_proc; /* proc entry */
@@ -1229,6 +1234,9 @@ struct f2fs_sb_info {
#endif
/* For which write hints are passed down to block layer */
int whint_mode;
+
+ /* segment allocation policy */
+ int alloc_mode;
};
#ifdef CONFIG_F2FS_FAULT_INJECTION