exofs: exofs_file_fsync and exofs_file_flush correctness

As per Christoph advise: no need to call filemap_write_and_wait(). In exofs all metadata is at the inode so just writing the inode is all is needed. ->fsync implies this must be done synchronously. But now exofs_file_fsync can not be used by exofs_file_flush. vfs_fsync() should do that job correctly. FIXME: remove the sb_sync and fix that sb_update better. Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

exofs: exofs_file_fsync and exofs_file_flush correctness
As per Christoph advise: no need to call filemap_write_and_wait(). In exofs all metadata is at the inode so just writing the inode is all is needed. ->fsync implies this must be done synchronously. But now exofs_file_fsync can not be used by exofs_file_flush. vfs_fsync() should do that job correctly. FIXME: remove the sb_sync and fix that sb_update better. Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Boaz Harrosh
1 parent 85dc7878c6
Showing 1 changed file with 17 additions and 12 deletions Side-by-side Diff
fs/exofs/file.c
@@ -30,9 +30,6 @@
  * along with exofs; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
-
-#include <linux/buffer_head.h>
-
 #include "exofs.h"
  
 static int exofs_release_file(struct inode *inode, struct file *filp)
  
  
  
@@ -40,19 +37,27 @@
 	return 0;
 }
  
+/* exofs_file_fsync - flush the inode to disk
+ *
+ *   Note, in exofs all metadata is written as part of inode, regardless.
+ *   The writeout is synchronous
+ */
 static int exofs_file_fsync(struct file *filp, int datasync)
 {
 	int ret;
-	struct address_space *mapping = filp->f_mapping;
-	struct inode *inode = mapping->host;
+	struct inode *inode = filp->f_mapping->host;
+	struct writeback_control wbc = {
+		.sync_mode = WB_SYNC_ALL,
+		.nr_to_write = 0, /* metadata-only; caller takes care of data */
+	};
 	struct super_block *sb;
  
-	ret = filemap_write_and_wait(mapping);
-	if (ret)
-		return ret;
+	if (!(inode->i_state & I_DIRTY))
+		return 0;
+	if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
+		return 0;
  
-	/* sync the inode attributes */
-	ret = write_inode_now(inode, 1);
+	ret = sync_inode(inode, &wbc);
  
 	/* This is a good place to write the sb */
 	/* TODO: Sechedule an sb-sync on create */
  
@@ -65,9 +70,9 @@
  
 static int exofs_flush(struct file *file, fl_owner_t id)
 {
-	exofs_file_fsync(file, 1);
+	int ret = vfs_fsync(file, 0);
 	/* TODO: Flush the OSD target */
-	return 0;
+	return ret;
 }
  
 const struct file_operations exofs_file_operations = {
...	...	@@ -30,9 +30,6 @@
30	30	* along with exofs; if not, write to the Free Software
31	31	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
32	32	*/
33		-
34		-#include <linux/buffer_head.h>
35		-
36	33	#include "exofs.h"
37	34
38	35	static int exofs_release_file(struct inode inode, struct file filp)
39	36
40	37
41	38
...	...	@@ -40,19 +37,27 @@
40	37	return 0;
41	38	}
42	39
	40	+/* exofs_file_fsync - flush the inode to disk
	41	+ *
	42	+ * Note, in exofs all metadata is written as part of inode, regardless.
	43	+ * The writeout is synchronous
	44	+ */
43	45	static int exofs_file_fsync(struct file *filp, int datasync)
44	46	{
45	47	int ret;
46		- struct address_space *mapping = filp->f_mapping;
47		- struct inode *inode = mapping->host;
	48	+ struct inode *inode = filp->f_mapping->host;
	49	+ struct writeback_control wbc = {
	50	+ .sync_mode = WB_SYNC_ALL,
	51	+ .nr_to_write = 0, /* metadata-only; caller takes care of data */
	52	+ };
48	53	struct super_block *sb;
49	54
50		- ret = filemap_write_and_wait(mapping);
51		- if (ret)
52		- return ret;
	55	+ if (!(inode->i_state & I_DIRTY))
	56	+ return 0;
	57	+ if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
	58	+ return 0;
53	59
54		- /* sync the inode attributes */
55		- ret = write_inode_now(inode, 1);
	60	+ ret = sync_inode(inode, &wbc);
56	61
57	62	/* This is a good place to write the sb */
58	63	/* TODO: Sechedule an sb-sync on create */
59	64
...	...	@@ -65,9 +70,9 @@
65	70
66	71	static int exofs_flush(struct file *file, fl_owner_t id)
67	72	{
68		- exofs_file_fsync(file, 1);
	73	+ int ret = vfs_fsync(file, 0);
69	74	/* TODO: Flush the OSD target */
70		- return 0;
	75	+ return ret;
71	76	}
72	77
73	78	const struct file_operations exofs_file_operations = {