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/super.c b/fs/f2fs/super.c
index 06da158..16d157e 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -130,6 +130,7 @@ enum {
Opt_jqfmt_vfsv0,
Opt_jqfmt_vfsv1,
Opt_whint,
+ Opt_alloc,
Opt_err,
};
@@ -184,6 +185,7 @@ static match_table_t f2fs_tokens = {
{Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
{Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
{Opt_whint, "whint_mode=%s"},
+ {Opt_alloc, "alloc_mode=%s"},
{Opt_err, NULL},
};
@@ -700,6 +702,23 @@ static int parse_options(struct super_block *sb, char *options)
}
kfree(name);
break;
+ case Opt_alloc:
+ name = match_strdup(&args[0]);
+ if (!name)
+ return -ENOMEM;
+
+ if (strlen(name) == 7 &&
+ !strncmp(name, "default", 7)) {
+ sbi->alloc_mode = ALLOC_MODE_DEFAULT;
+ } else if (strlen(name) == 5 &&
+ !strncmp(name, "reuse", 5)) {
+ sbi->alloc_mode = ALLOC_MODE_REUSE;
+ } else {
+ kfree(name);
+ return -EINVAL;
+ }
+ kfree(name);
+ break;
default:
f2fs_msg(sb, KERN_ERR,
"Unrecognized mount option \"%s\" or missing value",
@@ -1264,6 +1283,10 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
else if (sbi->whint_mode == WHINT_MODE_FS)
seq_printf(seq, ",whint_mode=%s", "fs-based");
+ if (sbi->alloc_mode == ALLOC_MODE_DEFAULT)
+ seq_printf(seq, ",alloc_mode=%s", "default");
+ else if (sbi->alloc_mode == ALLOC_MODE_REUSE)
+ seq_printf(seq, ",alloc_mode=%s", "reuse");
return 0;
}
@@ -1273,6 +1296,7 @@ static void default_options(struct f2fs_sb_info *sbi)
sbi->active_logs = NR_CURSEG_TYPE;
sbi->inline_xattr_size = DEFAULT_INLINE_XATTR_ADDRS;
sbi->whint_mode = WHINT_MODE_OFF;
+ sbi->alloc_mode = ALLOC_MODE_DEFAULT;
set_opt(sbi, BG_GC);
set_opt(sbi, INLINE_XATTR);
@@ -1314,6 +1338,7 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
bool need_stop_gc = false;
bool no_extent_cache = !test_opt(sbi, EXTENT_CACHE);
int old_whint_mode = sbi->whint_mode;
+ int old_alloc_mode = sbi->alloc_mode;
#ifdef CONFIG_F2FS_FAULT_INJECTION
struct f2fs_fault_info ffi = sbi->fault_info;
#endif
@@ -1463,6 +1488,7 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
sbi->s_qf_names[i] = s_qf_names[i];
}
#endif
+ sbi->alloc_mode = old_alloc_mode;
sbi->whint_mode = old_whint_mode;
sbi->mount_opt = org_mount_opt;
sbi->active_logs = active_logs;