2016-11-01 21:06:13

by Jan Kara

[permalink] [raw]
Subject: [PATCH 03/11] ext4: Let S_DAX set only 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.

Signed-off-by: Jan Kara <[email protected]>
---
fs/ext4/inline.c | 10 ++++++++++
fs/ext4/inode.c | 9 ++++++++-
fs/ext4/super.c | 5 +++++
3 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index f74d5ee2cdec..c29678965c3c 100644
--- 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 9eb1f89201ed..4cbd1b24c237 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4350,7 +4350,9 @@ 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);
@@ -5618,6 +5620,11 @@ 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 6db81fbcbaa6..c83d6f1cfab8 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1125,6 +1125,10 @@ 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;
}
@@ -1139,6 +1143,7 @@ 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 */
res = ext4_mark_inode_dirty(handle, inode);
if (res)
EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
--
2.6.6