ext4: evict inline data out if we need to strore xattr in inode

Now we that store data in the inode, in case we need to store some
xattrs and inode doesn't have enough space, Andreas suggested that we
should keep the xattr(metadata) in and data should be pushed out.  So
this patch does the work.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 43 insertions, 5 deletions

diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index bf5f77803885..cec651e2646c 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -207,8 +207,8 @@ out:
 /*
  * write the buffer to the inline inode.
  * If 'create' is set, we don't need to do the extra copy in the xattr
- * value since it is already handled by ext4_xattr_ibody_set. That saves
- * us one memcpy.
+ * value since it is already handled by ext4_xattr_ibody_inline_set.
+ * That saves us one memcpy.
  */
 void ext4_write_inline_data(struct inode *inode, struct ext4_iloc *iloc,
 			    void *buffer, loff_t pos, unsigned int len)
@@ -285,7 +285,7 @@ static int ext4_create_inline_data(handle_t *handle,
 
 	BUG_ON(!is.s.not_found);
 
-	error = ext4_xattr_ibody_set(handle, inode, &i, &is);
+	error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
 	if (error) {
 		if (error == -ENOSPC)
 			ext4_clear_inode_state(inode,
@@ -354,7 +354,7 @@ static int ext4_update_inline_data(handle_t *handle, struct inode *inode,
 	i.value = value;
 	i.value_len = len;
 
-	error = ext4_xattr_ibody_set(handle, inode, &i, &is);
+	error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
 	if (error)
 		goto out;
 
@@ -427,7 +427,7 @@ static int ext4_destroy_inline_data_nolock(handle_t *handle,
 	if (error)
 		goto out;
 
-	error = ext4_xattr_ibody_set(handle, inode, &i, &is);
+	error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
 	if (error)
 		goto out;
 
@@ -1715,3 +1715,41 @@ out:
 	up_read(&EXT4_I(inode)->xattr_sem);
 	return (error < 0 ? error : 0);
 }
+
+/*
+ * Called during xattr set, and if we can sparse space 'needed',
+ * just create the extent tree evict the data to the outer block.
+ *
+ * We use jbd2 instead of page cache to move data to the 1st block
+ * so that the whole transaction can be committed as a whole and
+ * the data isn't lost because of the delayed page cache write.
+ */
+int ext4_try_to_evict_inline_data(handle_t *handle,
+				  struct inode *inode,
+				  int needed)
+{
+	int error;
+	struct ext4_xattr_entry *entry;
+	struct ext4_xattr_ibody_header *header;
+	struct ext4_inode *raw_inode;
+	struct ext4_iloc iloc;
+
+	error = ext4_get_inode_loc(inode, &iloc);
+	if (error)
+		return error;
+
+	raw_inode = ext4_raw_inode(&iloc);
+	header = IHDR(inode, raw_inode);
+	entry = (struct ext4_xattr_entry *)((void *)raw_inode +
+					    EXT4_I(inode)->i_inline_off);
+	if (EXT4_XATTR_LEN(entry->e_name_len) +
+	    EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size)) < needed) {
+		error = -ENOSPC;
+		goto out;
+	}
+
+	error = ext4_convert_inline_data_nolock(handle, inode, &iloc);
+out:
+	brelse(iloc.bh);
+	return error;
+}