[PATCH V1 6/9] fs/ext4: Only change S_DAX on inode load

ira.weiny
2020-05-14T06:53:45Z

To prevent complications with in memory inodes we only set S_DAX on
inode load. FS_XFLAG_DAX can be changed at any time and S_DAX will
change after inode eviction and reload.

Add init bool to ext4_set_inode_flags() to indicate if the inode is
being newly initialized.

Assert that S_DAX is not set on an inode which is just being loaded.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>

---
Changes from RFC:
Change J_ASSERT() to WARN_ON_ONCE()
Fix bug which would clear S_DAX incorrectly
---
fs/ext4/ext4.h | 2 +-
fs/ext4/ialloc.c | 2 +-
fs/ext4/inode.c | 13 ++++++++++---
fs/ext4/ioctl.c | 3 ++-
fs/ext4/super.c | 4 ++--
fs/ext4/verity.c | 2 +-
6 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 1a3daf2d18ef..86a0994332ce 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2692,7 +2692,7 @@ extern int ext4_can_truncate(struct inode *inode);
extern int ext4_truncate(struct inode *);
extern int ext4_break_layouts(struct inode *);
extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length);
-extern void ext4_set_inode_flags(struct inode *);
+extern void ext4_set_inode_flags(struct inode *, bool init);
extern int ext4_alloc_da_blocks(struct inode *inode);
extern void ext4_set_aops(struct inode *inode);
extern int ext4_writepage_trans_blocks(struct inode *);
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 4b8c9a9bdf0c..7941c140723f 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -1116,7 +1116,7 @@ struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir,
ei->i_block_group = group;
ei->i_last_alloc_group = ~0;

- ext4_set_inode_flags(inode);
+ ext4_set_inode_flags(inode, true);
if (IS_DIRSYNC(inode))
ext4_handle_sync(handle);
if (insert_inode_locked(inode) < 0) {
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index d3a4c2ed7a1c..23e42a223235 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4419,11 +4419,13 @@ static bool ext4_should_enable_dax(struct inode *inode)
return false;
}

-void ext4_set_inode_flags(struct inode *inode)
+void ext4_set_inode_flags(struct inode *inode, bool init)
{
unsigned int flags = EXT4_I(inode)->i_flags;
unsigned int new_fl = 0;

+ WARN_ON_ONCE(IS_DAX(inode) && init);
+
if (flags & EXT4_SYNC_FL)
new_fl |= S_SYNC;
if (flags & EXT4_APPEND_FL)
@@ -4434,8 +4436,13 @@ void ext4_set_inode_flags(struct inode *inode)
new_fl |= S_NOATIME;
if (flags & EXT4_DIRSYNC_FL)
new_fl |= S_DIRSYNC;
- if (ext4_should_enable_dax(inode))
+
+ /* Because of the way inode_set_flags() works we must preserve S_DAX
+ * here if already set. */
+ new_fl |= (inode->i_flags & S_DAX);
+ if (init && ext4_should_enable_dax(inode))
new_fl |= S_DAX;
+
if (flags & EXT4_ENCRYPT_FL)
new_fl |= S_ENCRYPTED;
if (flags & EXT4_CASEFOLD_FL)
@@ -4649,7 +4656,7 @@ struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
* not initialized on a new filesystem. */
}
ei->i_flags = le32_to_cpu(raw_inode->i_flags);
- ext4_set_inode_flags(inode);
+ ext4_set_inode_flags(inode, true);
inode->i_blocks = ext4_inode_blocks(raw_inode, ei);
ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo);
if (ext4_has_feature_64bit(sb))
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 5813e5e73eab..145083e8cd1e 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -381,7 +381,8 @@ static int ext4_ioctl_setflags(struct inode *inode,
ext4_clear_inode_flag(inode, i);
}

- ext4_set_inode_flags(inode);
+ ext4_set_inode_flags(inode, false);
+
inode->i_ctime = current_time(inode);

err = ext4_mark_iloc_dirty(handle, inode, &iloc);
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index d0434b513919..5ec900fdf73c 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1344,7 +1344,7 @@ static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
ext4_clear_inode_state(inode,
EXT4_STATE_MAY_INLINE_DATA);
- ext4_set_inode_flags(inode);
+ ext4_set_inode_flags(inode, false);
}
return res;
}
@@ -1367,7 +1367,7 @@ static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
ctx, len, 0);
if (!res) {
ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
- ext4_set_inode_flags(inode);
+ ext4_set_inode_flags(inode, false);
res = ext4_mark_inode_dirty(handle, inode);
if (res)
EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
diff --git a/fs/ext4/verity.c b/fs/ext4/verity.c
index f05a09fb2ae4..89a155ece323 100644
--- a/fs/ext4/verity.c
+++ b/fs/ext4/verity.c
@@ -244,7 +244,7 @@ static int ext4_end_enable_verity(struct file *filp, const void *desc,
if (err)
goto out_stop;
ext4_set_inode_flag(inode, EXT4_INODE_VERITY);
- ext4_set_inode_flags(inode);
+ ext4_set_inode_flags(inode, false);
err = ext4_mark_iloc_dirty(handle, inode, &iloc);
}
out_stop:
--
2.25.1