ext4: only set S_DAX if DAX is really supported

Currently we have S_DAX set inode->i_flags for a regular file whenever
ext4 is mounted with dax mount option. However in some cases we cannot
really do DAX - e.g. when inode is marked to use data journalling, when
inode data is being encrypted, or when inode is stored inline. Make sure
S_DAX flag is appropriately set/cleared in these cases.

Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index cfa87bd49c5a61b904d7e960da1a61c39cfd874a..9b67f75bdcf74b91b7db4f1bf408abfbd2e9d75d 100644 (file)
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -299,6 +299,11 @@ static int ext4_create_inline_data(handle_t *handle,
        EXT4_I(inode)->i_inline_size = len + EXT4_MIN_INLINE_DATA_SIZE;
        ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
        ext4_set_inode_flag(inode, EXT4_INODE_INLINE_DATA);
+       /*
+        * Propagate changes to inode->i_flags as well - e.g. S_DAX may
+        * get cleared
+        */
+       ext4_set_inode_flags(inode);
        get_bh(is.iloc.bh);
        error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
 
@@ -442,6 +447,11 @@ static int ext4_destroy_inline_data_nolock(handle_t *handle,
                }
        }
        ext4_clear_inode_flag(inode, EXT4_INODE_INLINE_DATA);
+       /*
+        * Propagate changes to inode->i_flags as well - e.g. S_DAX may
+        * get set.
+        */
+       ext4_set_inode_flags(inode);
 
        get_bh(is.iloc.bh);
        error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index b1b4c85bbae385e89f2ea3c526fe409dda4ae9cb..733fda1c3646da25397a826a81fa6090ce9f312f 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4368,7 +4368,9 @@ void ext4_set_inode_flags(struct inode *inode)
                new_fl |= S_NOATIME;
        if (flags & EXT4_DIRSYNC_FL)
                new_fl |= S_DIRSYNC;
-       if (test_opt(inode->i_sb, DAX) && S_ISREG(inode->i_mode))
+       if (test_opt(inode->i_sb, DAX) && S_ISREG(inode->i_mode) &&
+           !ext4_should_journal_data(inode) && !ext4_has_inline_data(inode) &&
+           !ext4_encrypted_inode(inode))
                new_fl |= S_DAX;
        inode_set_flags(inode, new_fl,
                        S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_DAX);
@@ -5641,6 +5643,11 @@ int ext4_change_inode_journal_flag(struct inode *inode, int val)
                ext4_clear_inode_flag(inode, EXT4_INODE_JOURNAL_DATA);
        }
        ext4_set_aops(inode);
+       /*
+        * Update inode->i_flags after EXT4_INODE_JOURNAL_DATA was updated.
+        * E.g. S_DAX may get cleared / set.
+        */
+       ext4_set_inode_flags(inode);
 
        jbd2_journal_unlock_updates(journal);
        percpu_up_write(&sbi->s_journal_flag_rwsem);

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 2d8a49d74f5676beba39ec610550e637f216fdf0..cbfaee175fa5eeb43872f292c90cefe9626023ea 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1126,6 +1126,10 @@ 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);
+                       /*
+                        * Update inode->i_flags - e.g. S_DAX may get disabled
+                        */
+                       ext4_set_inode_flags(inode);
                }
                return res;
        }
@@ -1140,6 +1144,8 @@ static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
                        len, 0);
        if (!res) {
                ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
+               /* Update inode->i_flags - e.g. S_DAX may get disabled */
+               ext4_set_inode_flags(inode);
                res = ext4_mark_inode_dirty(handle, inode);
                if (res)
                        EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");