ext2 reservations and ->put_inode

ext2 reservations and ->put_inode

[Christoph Hellwig]

Hi Mingming,

you'd been reworking ext3 reservations to be dropped in ->clear_inode
instead of the previous bogus call in ->put_inode in
ext3-lazy-discard-reservation-window-patch.patch in -mm.

Any chance you could submit a similar change (not the full reservations
rework) for ext2?

Re: ext2 reservations and ->put_inode

[Mingming Cao]

On Thu, 2004-10-14 at 04:41, Christoph Hellwig wrote:
> Hi Mingming,
> 
> you'd been reworking ext3 reservations to be dropped in ->clear_inode
> instead of the previous bogus call in ->put_inode in
> ext3-lazy-discard-reservation-window-patch.patch in -mm.
> 
> Any chance you could submit a similar change (not the full reservations
> rework) for ext2?
> 
You are right. We should fix this in ext2. I will post a patch separately.

Thanks!
Mingming

[PATCH 1/1] discard ext2 preallocation in last iput

[Mingming Cao]

On Thu, 2004-10-14 at 04:41, Christoph Hellwig wrote:
> Hi Mingming,
> 
> you'd been reworking ext3 reservations to be dropped in ->clear_inode
> instead of the previous bogus call in ->put_inode in
> ext3-lazy-discard-reservation-window-patch.patch in -mm.
> 
> Any chance you could submit a similar change (not the full reservations
> rework) for ext2?
> 
Andrew,

Here is the patch for ext2. The patch is against 2.6.9-rc4. I have done
basic testing: it passed the fsstress test from LTP on a ext2 partition.

Thanks,
Mingming

Currently the ext2 preallocation is discarded on every iput()(via ext2_put_inode()). We should only discard the preallocation on the last iput()(via ext3_clear_inode()).


---

 linux-2.6.9-rc4-ming/fs/ext2/ext2.h  |    1 -
 linux-2.6.9-rc4-ming/fs/ext2/inode.c |   13 -------------
 linux-2.6.9-rc4-ming/fs/ext2/super.c |   10 ++++------
 3 files changed, 4 insertions(+), 20 deletions(-)

diff -puN fs/ext2/inode.c~ext2_discard_prealloc_fix fs/ext2/inode.c
--- linux-2.6.9-rc4/fs/ext2/inode.c~ext2_discard_prealloc_fix	2004-10-14 18:02:38.458168192 -0700
+++ linux-2.6.9-rc4-ming/fs/ext2/inode.c	2004-10-14 18:12:03.002344432 -0700
@@ -53,19 +53,6 @@ static inline int ext2_inode_is_fast_sym
 }
 
 /*
- * Called at each iput().
- *
- * The inode may be "bad" if ext2_read_inode() saw an error from
- * ext2_get_inode(), so we need to check that to avoid freeing random disk
- * blocks.
- */
-void ext2_put_inode(struct inode *inode)
-{
-	if (!is_bad_inode(inode))
-		ext2_discard_prealloc(inode);
-}
-
-/*
  * Called at the last iput() if i_nlink is zero.
  */
 void ext2_delete_inode (struct inode * inode)
diff -puN fs/ext2/super.c~ext2_discard_prealloc_fix fs/ext2/super.c
--- linux-2.6.9-rc4/fs/ext2/super.c~ext2_discard_prealloc_fix	2004-10-14 18:06:55.525088080 -0700
+++ linux-2.6.9-rc4-ming/fs/ext2/super.c	2004-10-14 19:05:47.943078920 -0700
@@ -181,10 +181,9 @@ static void destroy_inodecache(void)
 		printk(KERN_INFO "ext2_inode_cache: not all structures were freed\n");
 }
 
-#ifdef CONFIG_EXT2_FS_POSIX_ACL
-
 static void ext2_clear_inode(struct inode *inode)
 {
+#ifdef CONFIG_EXT2_FS_POSIX_ACL
 	struct ext2_inode_info *ei = EXT2_I(inode);
 
 	if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) {
@@ -195,18 +194,17 @@ static void ext2_clear_inode(struct inod
 		posix_acl_release(ei->i_default_acl);
 		ei->i_default_acl = EXT2_ACL_NOT_CACHED;
 	}
+#endif
+	if (!is_bad_inode(inode))
+		ext2_discard_prealloc(inode);
 }
 
-#else
-# define ext2_clear_inode NULL
-#endif
 
 static struct super_operations ext2_sops = {
 	.alloc_inode	= ext2_alloc_inode,
 	.destroy_inode	= ext2_destroy_inode,
 	.read_inode	= ext2_read_inode,
 	.write_inode	= ext2_write_inode,
-	.put_inode	= ext2_put_inode,
 	.delete_inode	= ext2_delete_inode,
 	.put_super	= ext2_put_super,
 	.write_super	= ext2_write_super,
diff -puN fs/ext2/ext2.h~ext2_discard_prealloc_fix fs/ext2/ext2.h
--- linux-2.6.9-rc4/fs/ext2/ext2.h~ext2_discard_prealloc_fix	2004-10-14 18:59:22.688646496 -0700
+++ linux-2.6.9-rc4-ming/fs/ext2/ext2.h	2004-10-14 18:59:33.820954128 -0700
@@ -116,7 +116,6 @@ extern unsigned long ext2_count_free (st
 /* inode.c */
 extern void ext2_read_inode (struct inode *);
 extern int ext2_write_inode (struct inode *, int);
-extern void ext2_put_inode (struct inode *);
 extern void ext2_delete_inode (struct inode *);
 extern int ext2_sync_inode (struct inode *);
 extern void ext2_discard_prealloc (struct inode *);

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