From: Chao Yu <yuch...@huawei.com>
Later after this patch was merged, all new incompatible feature's
bit should be added into sb.required_features field, and define new
feature function with F2FS_INCOMPAT_FEATURE_FUNCS() macro.
Then during mount, we will do sanity check with enabled features in
image, if there are features in sb.required_features that kernel can
not recognize, just fail the mount.
Signed-off-by: Chao Yu <yuch...@huawei.com>
---
v3:
- change commit title.
- fix wrong macro name.
fs/f2fs/f2fs.h | 15 +++++++++++++++
fs/f2fs/super.c | 10 ++++++++++
include/linux/f2fs_fs.h | 3 ++-
3 files changed, 27 insertions(+), 1 deletion(-)
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index a6eb828af57f..b8e17d4ddb8d 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -163,6 +163,15 @@ struct f2fs_mount_info {
#define F2FS_CLEAR_FEATURE(sbi, mask) \
(sbi->raw_super->feature &= ~cpu_to_le32(mask))
+#define F2FS_INCOMPAT_FEATURES 0
+
+#define F2FS_HAS_INCOMPAT_FEATURE(sbi, mask) \
+ ((sbi->raw_super->required_features & cpu_to_le32(mask)) != 0)
+#define F2FS_SET_INCOMPAT_FEATURE(sbi, mask) \
+ (sbi->raw_super->required_features |= cpu_to_le32(mask))
+#define F2FS_CLEAR_INCOMPAT_FEATURE(sbi, mask) \
+ (sbi->raw_super->required_features &= ~cpu_to_le32(mask))
+
/*
* Default values for user and/or group using reserved blocks
*/
@@ -3585,6 +3594,12 @@ F2FS_FEATURE_FUNCS(lost_found, LOST_FOUND);
F2FS_FEATURE_FUNCS(sb_chksum, SB_CHKSUM);
F2FS_FEATURE_FUNCS(casefold, CASEFOLD);
+#define F2FS_INCOMPAT_FEATURE_FUNCS(name, flagname) \
+static inline int f2fs_sb_has_##name(struct f2fs_sb_info *sbi) \
+{ \
+ return F2FS_HAS_INCOMPAT_FEATURE(sbi, F2FS_FEATURE_##flagname); \
+}
+
#ifdef CONFIG_BLK_DEV_ZONED
static inline bool f2fs_blkz_is_seq(struct f2fs_sb_info *sbi, int devi,
block_t blkaddr)
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 5540fee0fe3f..3701dcce90e6 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -2513,6 +2513,16 @@ static int sanity_check_raw_super(struct f2fs_sb_info
*sbi,
return -EINVAL;
}
+ /* check whether current kernel supports all features on image */
+ if (le32_to_cpu(raw_super->required_features) &
+ ~F2FS_INCOMPAT_FEATURES) {
+ f2fs_info(sbi, "Unsupported feature: %x: supported: %x",
+ le32_to_cpu(raw_super->required_features) ^
+ F2FS_INCOMPAT_FEATURES,
+ F2FS_INCOMPAT_FEATURES);
+ return -EINVAL;
+ }
+
/* Check checksum_offset and crc in superblock */
if (__F2FS_HAS_FEATURE(raw_super, F2FS_FEATURE_SB_CHKSUM)) {
crc_offset = le32_to_cpu(raw_super->checksum_offset);
diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
index a2b36b2e286f..4141be3f219c 100644
--- a/include/linux/f2fs_fs.h
+++ b/include/linux/f2fs_fs.h
@@ -117,7 +117,8 @@ struct f2fs_super_block {
__u8 hot_ext_count; /* # of hot file extension */
__le16 s_encoding; /* Filename charset encoding */
__le16 s_encoding_flags; /* Filename charset encoding flags */
- __u8 reserved[306]; /* valid reserved region */
+ __le32 required_features; /* incompatible features to old kernel
*/
+ __u8 reserved[302]; /* valid reserved region */
__le32 crc; /* checksum of superblock */
} __packed;
--
2.22.0
