[PATCH v2] f2fs: support inode checksum

From: Chao Yu
Date: Mon Jul 31 2017 - 08:19:44 EST


This patch adds to support inode checksum in f2fs.

Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
v2: add to print detail info if checksum failed.
fs/f2fs/f2fs.h | 31 +++++++++++++++++++++++
fs/f2fs/inode.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++++
fs/f2fs/node.c | 2 ++
fs/f2fs/segment.c | 5 +++-
fs/f2fs/super.c | 5 ++++
include/linux/f2fs_fs.h | 1 +
6 files changed, 109 insertions(+), 1 deletion(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index a1bfd0b9be44..d35621b8d739 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -116,6 +116,7 @@ struct f2fs_mount_info {
#define F2FS_FEATURE_ATOMIC_WRITE 0x0004
#define F2FS_FEATURE_EXTRA_ATTR 0x0008
#define F2FS_FEATURE_PRJQUOTA 0x0010
+#define F2FS_FEATURE_INODE_CHKSUM 0x0020

#define F2FS_HAS_FEATURE(sb, mask) \
((F2FS_SB(sb)->raw_super->feature & cpu_to_le32(mask)) != 0)
@@ -1082,6 +1083,9 @@ struct f2fs_sb_info {
/* Reference to checksum algorithm driver via cryptoapi */
struct crypto_shash *s_chksum_driver;

+ /* Precomputed FS UUID checksum for seeding other checksums */
+ __u32 s_chksum_seed;
+
/* For fault injection */
#ifdef CONFIG_F2FS_FAULT_INJECTION
struct f2fs_fault_info fault_info;
@@ -1173,6 +1177,27 @@ static inline bool f2fs_crc_valid(struct f2fs_sb_info *sbi, __u32 blk_crc,
return f2fs_crc32(sbi, buf, buf_size) == blk_crc;
}

+static inline u32 f2fs_chksum(struct f2fs_sb_info *sbi, u32 crc,
+ const void *address, unsigned int length)
+{
+ struct {
+ struct shash_desc shash;
+ char ctx[4];
+ } desc;
+ int err;
+
+ BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver) != sizeof(desc.ctx));
+
+ desc.shash.tfm = sbi->s_chksum_driver;
+ desc.shash.flags = 0;
+ *(u32 *)desc.ctx = crc;
+
+ err = crypto_shash_update(&desc.shash, address, length);
+ BUG_ON(err);
+
+ return *(u32 *)desc.ctx;
+}
+
static inline struct f2fs_inode_info *F2FS_I(struct inode *inode)
{
return container_of(inode, struct f2fs_inode_info, vfs_inode);
@@ -2282,6 +2307,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
* inode.c
*/
void f2fs_set_inode_flags(struct inode *inode);
+void f2fs_inode_chksum_set(struct f2fs_sb_info *sbi, struct f2fs_node *node);
struct inode *f2fs_iget(struct super_block *sb, unsigned long ino);
struct inode *f2fs_iget_retry(struct super_block *sb, unsigned long ino);
int try_to_free_nats(struct f2fs_sb_info *sbi, int nr_shrink);
@@ -2865,6 +2891,11 @@ static inline int f2fs_sb_has_project_quota(struct super_block *sb)
return F2FS_HAS_FEATURE(sb, F2FS_FEATURE_PRJQUOTA);
}

+static inline int f2fs_sb_has_inode_chksum(struct super_block *sb)
+{
+ return F2FS_HAS_FEATURE(sb, F2FS_FEATURE_INODE_CHKSUM);
+}
+
#ifdef CONFIG_BLK_DEV_ZONED
static inline int get_blkz_type(struct f2fs_sb_info *sbi,
struct block_device *bdev, block_t blkaddr)
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index f15e663a1a15..05c8aeb0101e 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -108,6 +108,64 @@ static void __recover_inline_status(struct inode *inode, struct page *ipage)
return;
}

+static __u32 f2fs_inode_chksum(struct f2fs_sb_info *sbi,
+ struct f2fs_node *node)
+{
+ struct f2fs_inode *ri = &node->i;
+ __le32 ino = node->footer.ino;
+ __le32 gen = ri->i_generation;
+ __u32 chksum, chksum_seed;
+ __u32 dummy_cs = 0;
+ unsigned int offset = offsetof(struct f2fs_inode, i_inode_checksum);
+ unsigned int cs_size = sizeof(dummy_cs);
+
+ chksum = f2fs_chksum(sbi, sbi->s_chksum_seed, (__u8 *)&ino,
+ sizeof(ino));
+ chksum_seed = f2fs_chksum(sbi, chksum, (__u8 *)&gen, sizeof(gen));
+
+ chksum = f2fs_chksum(sbi, chksum_seed, (__u8 *)ri, offset);
+ chksum = f2fs_chksum(sbi, chksum, (__u8 *)&dummy_cs, cs_size);
+ offset += cs_size;
+ chksum = f2fs_chksum(sbi, chksum, (__u8 *)ri + offset,
+ F2FS_BLKSIZE - offset);
+ return chksum;
+}
+
+static bool f2fs_inode_chksum_verify(struct f2fs_sb_info *sbi,
+ struct f2fs_node *node, struct f2fs_inode_info *fi)
+{
+ struct f2fs_inode *ri = &node->i;
+ __u32 provided, calculated;
+
+ if (!f2fs_sb_has_inode_chksum(sbi->sb))
+ return true;
+
+ if (!F2FS_FITS_IN_INODE(ri, fi->i_extra_isize, i_inode_checksum))
+ return true;
+
+ provided = le32_to_cpu(ri->i_inode_checksum);
+ calculated = f2fs_inode_chksum(sbi, node);
+
+ return provided == calculated;
+}
+
+void f2fs_inode_chksum_set(struct f2fs_sb_info *sbi, struct f2fs_node *node)
+{
+ struct f2fs_inode *ri = &node->i;
+ int extra_isize = le32_to_cpu(ri->i_extra_isize);
+
+ if (!f2fs_sb_has_inode_chksum(sbi->sb))
+ return;
+
+ if (!RAW_IS_INODE(node) || !(ri->i_inline & F2FS_EXTRA_ATTR))
+ return;
+
+ if (!F2FS_FITS_IN_INODE(ri, extra_isize, i_inode_checksum))
+ return;
+
+ ri->i_inode_checksum = cpu_to_le32(f2fs_inode_chksum(sbi, node));
+}
+
static int do_read_inode(struct inode *inode)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
@@ -161,6 +219,14 @@ static int do_read_inode(struct inode *inode)
fi->i_extra_isize = f2fs_has_extra_attr(inode) ?
le16_to_cpu(ri->i_extra_isize) : 0;

+ if (!f2fs_inode_chksum_verify(sbi, F2FS_NODE(node_page), fi)) {
+ f2fs_msg(sbi->sb, KERN_WARNING,
+ "checksum invalid, ino:%lu, on-disk:%u",
+ inode->i_ino, le32_to_cpu(ri->i_inode_checksum));
+ f2fs_put_page(node_page, 1);
+ return -EBADMSG;
+ }
+
/* check data exist */
if (f2fs_has_inline_data(inode) && !f2fs_exist_data(inode))
__recover_inline_status(inode, node_page);
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 11e2d49203b3..f97792202ada 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -2271,6 +2271,8 @@ int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page)
F2FS_FITS_IN_INODE(src, le16_to_cpu(src->i_extra_isize),
i_projid))
dst->i_projid = src->i_projid;
+
+ f2fs_inode_chksum_set(sbi, F2FS_NODE(ipage));
}

new_ni = old_ni;
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 2a5672a20a62..df1bb0c144f1 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -2214,9 +2214,12 @@ void allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,

mutex_unlock(&sit_i->sentry_lock);

- if (page && IS_NODESEG(type))
+ if (page && IS_NODESEG(type)) {
fill_node_footer_blkaddr(page, NEXT_FREE_BLKADDR(sbi, curseg));

+ f2fs_inode_chksum_set(sbi, F2FS_NODE(page));
+ }
+
if (add_list) {
struct f2fs_bio_info *io;

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index f44a09375e64..043908e1869c 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1945,6 +1945,11 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
sb->s_fs_info = sbi;
sbi->raw_super = raw_super;

+ /* precompute checksum seed for metadata */
+ if (f2fs_sb_has_inode_chksum(sb))
+ sbi->s_chksum_seed = f2fs_chksum(sbi, ~0, raw_super->uuid,
+ sizeof(raw_super->uuid));
+
/*
* The BLKZONED feature indicates that the drive was formatted with
* zone alignment optimization. This is optional for host-aware
diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
index 50f176683676..2a0c453d7235 100644
--- a/include/linux/f2fs_fs.h
+++ b/include/linux/f2fs_fs.h
@@ -240,6 +240,7 @@ struct f2fs_inode {
__le16 i_extra_isize; /* extra inode attribute size */
__le16 i_padding; /* padding */
__le32 i_projid; /* project id */
+ __le32 i_inode_checksum;/* inode meta checksum */
__le32 i_extra_end[0]; /* for attribute size calculation */
};
__le32 i_addr[DEF_ADDRS_PER_INODE]; /* Pointers to data blocks */
--
2.13.1.388.g69e6b9b4f4a9