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* [PATCH] ext4: Remove blocks from inode prealloc list on failure
@ 2009-12-01 18:17 Curt Wohlgemuth
  2009-12-04  1:10 ` tytso
  2009-12-04  9:46 ` Aneesh Kumar K.V
  0 siblings, 2 replies; 6+ messages in thread
From: Curt Wohlgemuth @ 2009-12-01 18:17 UTC (permalink / raw)
  To: ext4 development

This fixes a leak of blocks in an inode prealloc list if device failures
cause ext4_mb_mark_diskspace_used() to fail.

Signed-off-by: Curt Wohlgemuth <curtw@google.com>
---
diff -uprN orig/fs/ext4/mballoc.c new/fs/ext4/mballoc.c
--- orig/fs/ext4/mballoc.c	2009-12-01 09:27:25.000000000 -0800
+++ new/fs/ext4/mballoc.c	2009-12-01 09:28:38.000000000 -0800
@@ -3011,6 +3011,22 @@ static void ext4_mb_collect_stats(struct
 }

 /*
+ * Called on failure; free up any blocks from the inode PA for this
+ * context.
+ */
+static void ext4_discard_inode_pa(struct ext4_allocation_context *ac)
+{
+	struct ext4_prealloc_space *pa = ac->ac_pa;
+	int len;
+
+	if (pa && pa->pa_type == MB_INODE_PA) {
+		len = ac->ac_b_ex.fe_len;
+		pa->pa_free += len;
+	}
+
+}
+
+/*
  * use blocks preallocated to inode
  */
 static void ext4_mb_use_inode_pa(struct ext4_allocation_context *ac,
@@ -4295,6 +4311,7 @@ repeat:
 			ac->ac_status = AC_STATUS_CONTINUE;
 			goto repeat;
 		} else if (*errp) {
+			ext4_discard_inode_pa(ac);
 			ac->ac_b_ex.fe_len = 0;
 			ar->len = 0;
 			ext4_mb_show_ac(ac);

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] ext4: Remove blocks from inode prealloc list on failure
  2009-12-01 18:17 [PATCH] ext4: Remove blocks from inode prealloc list on failure Curt Wohlgemuth
@ 2009-12-04  1:10 ` tytso
  2009-12-04  9:43   ` Aneesh Kumar K.V
  2009-12-04  9:46 ` Aneesh Kumar K.V
  1 sibling, 1 reply; 6+ messages in thread
From: tytso @ 2009-12-04  1:10 UTC (permalink / raw)
  To: Curt Wohlgemuth; +Cc: ext4 development

On Tue, Dec 01, 2009 at 10:17:02AM -0800, Curt Wohlgemuth wrote:
> This fixes a leak of blocks in an inode prealloc list if device failures
> cause ext4_mb_mark_diskspace_used() to fail.

I was going to say that it didn't make sense for
ext4_discard_inode_pa() should be its own function, but maybe we need
function that returns blocks back to the either inode *or* the group
preallocation list?  Otherwise right now it looks like we would also
be potentially leaking blocks from the group preallocation list in
case of a device failure?

					- Ted

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] ext4: Remove blocks from inode prealloc list on failure
  2009-12-04  1:10 ` tytso
@ 2009-12-04  9:43   ` Aneesh Kumar K.V
  0 siblings, 0 replies; 6+ messages in thread
From: Aneesh Kumar K.V @ 2009-12-04  9:43 UTC (permalink / raw)
  To: tytso; +Cc: Curt Wohlgemuth, ext4 development

On Thu, Dec 03, 2009 at 08:10:22PM -0500, tytso@mit.edu wrote:
> On Tue, Dec 01, 2009 at 10:17:02AM -0800, Curt Wohlgemuth wrote:
> > This fixes a leak of blocks in an inode prealloc list if device failures
> > cause ext4_mb_mark_diskspace_used() to fail.
> 
> I was going to say that it didn't make sense for
> ext4_discard_inode_pa() should be its own function, but maybe we need
> function that returns blocks back to the either inode *or* the group
> preallocation list?  Otherwise right now it looks like we would also
> be potentially leaking blocks from the group preallocation list in
> case of a device failure?

For group preallocation we update the group prealloc values in 
ext4_mb_release_context and we use  ac->ac_b_ex.fe_len  to find
out the count of blocks allocated. So i guess we are not going
to leak blocks from group prealloc space.

-aneesh

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] ext4: Remove blocks from inode prealloc list on failure
  2009-12-01 18:17 [PATCH] ext4: Remove blocks from inode prealloc list on failure Curt Wohlgemuth
  2009-12-04  1:10 ` tytso
@ 2009-12-04  9:46 ` Aneesh Kumar K.V
  2009-12-04 19:14   ` Curt Wohlgemuth
  1 sibling, 1 reply; 6+ messages in thread
From: Aneesh Kumar K.V @ 2009-12-04  9:46 UTC (permalink / raw)
  To: Curt Wohlgemuth; +Cc: ext4 development

On Tue, Dec 01, 2009 at 10:17:02AM -0800, Curt Wohlgemuth wrote:
> This fixes a leak of blocks in an inode prealloc list if device failures
> cause ext4_mb_mark_diskspace_used() to fail.
> 
> Signed-off-by: Curt Wohlgemuth <curtw@google.com>
> ---
> diff -uprN orig/fs/ext4/mballoc.c new/fs/ext4/mballoc.c
> --- orig/fs/ext4/mballoc.c	2009-12-01 09:27:25.000000000 -0800
> +++ new/fs/ext4/mballoc.c	2009-12-01 09:28:38.000000000 -0800
> @@ -3011,6 +3011,22 @@ static void ext4_mb_collect_stats(struct
>  }
> 
>  /*
> + * Called on failure; free up any blocks from the inode PA for this
> + * context.
> + */
> +static void ext4_discard_inode_pa(struct ext4_allocation_context *ac)
> +{
> +	struct ext4_prealloc_space *pa = ac->ac_pa;
> +	int len;
> +
> +	if (pa && pa->pa_type == MB_INODE_PA) {
> +		len = ac->ac_b_ex.fe_len;
> +		pa->pa_free += len;
> +	}
> +
> +}

Can you name it as discard allocated blocks and add a comment saying why
we don't need it for MB_GROUP_PA ? Otherwise

Acked-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>


> +
> +/*
>   * use blocks preallocated to inode
>   */
>  static void ext4_mb_use_inode_pa(struct ext4_allocation_context *ac,
> @@ -4295,6 +4311,7 @@ repeat:
>  			ac->ac_status = AC_STATUS_CONTINUE;
>  			goto repeat;
>  		} else if (*errp) {
> +			ext4_discard_inode_pa(ac);
>  			ac->ac_b_ex.fe_len = 0;
>  			ar->len = 0;
>  			ext4_mb_show_ac(ac);
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] ext4: Remove blocks from inode prealloc list on failure
  2009-12-04  9:46 ` Aneesh Kumar K.V
@ 2009-12-04 19:14   ` Curt Wohlgemuth
  2009-12-09  3:21     ` tytso
  0 siblings, 1 reply; 6+ messages in thread
From: Curt Wohlgemuth @ 2009-12-04 19:14 UTC (permalink / raw)
  To: Aneesh Kumar K.V; +Cc: ext4 development

> Can you name it as discard allocated blocks and add a comment saying why
> we don't need it for MB_GROUP_PA ? Otherwise
>
> Acked-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

This fixes a leak of blocks in an inode prealloc list if device failures
cause ext4_mb_mark_diskspace_used() to fail.

Signed-off-by: Curt Wohlgemuth <curtw@google.com>
---
diff -uprN orig/fs/ext4/mballoc.c new/fs/ext4/mballoc.c
--- orig/fs/ext4/mballoc.c	2009-12-01 09:27:25.000000000 -0800
+++ new/fs/ext4/mballoc.c	2009-12-04 11:09:03.000000000 -0800
@@ -3011,6 +3011,24 @@ static void ext4_mb_collect_stats(struct
 }

 /*
+ * Called on failure; free up any blocks from the inode PA for this
+ * context.  We don't need this for MB_GROUP_PA because we only change
+ * pa_free in ext4_mb_release_context(), but on failure, we've already
+ * zeroed out ac->ac_b_ex.fe_len, so group_pa->pa_free is not changed.
+ */
+static void ext4_discard_allocated_blocks(struct ext4_allocation_context *ac)
+{
+	struct ext4_prealloc_space *pa = ac->ac_pa;
+	int len;
+
+	if (pa && pa->pa_type == MB_INODE_PA) {
+		len = ac->ac_b_ex.fe_len;
+		pa->pa_free += len;
+	}
+
+}
+
+/*
  * use blocks preallocated to inode
  */
 static void ext4_mb_use_inode_pa(struct ext4_allocation_context *ac,
@@ -4295,6 +4313,7 @@ repeat:
 			ac->ac_status = AC_STATUS_CONTINUE;
 			goto repeat;
 		} else if (*errp) {
+			ext4_discard_allocated_blocks(ac);
 			ac->ac_b_ex.fe_len = 0;
 			ar->len = 0;
 			ext4_mb_show_ac(ac);

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] ext4: Remove blocks from inode prealloc list on failure
  2009-12-04 19:14   ` Curt Wohlgemuth
@ 2009-12-09  3:21     ` tytso
  0 siblings, 0 replies; 6+ messages in thread
From: tytso @ 2009-12-09  3:21 UTC (permalink / raw)
  To: Curt Wohlgemuth; +Cc: Aneesh Kumar K.V, ext4 development

On Fri, Dec 04, 2009 at 11:14:40AM -0800, Curt Wohlgemuth wrote:
> > Can you name it as discard allocated blocks and add a comment saying why
> > we don't need it for MB_GROUP_PA ? Otherwise
> >
> > Acked-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> 
> This fixes a leak of blocks in an inode prealloc list if device failures
> cause ext4_mb_mark_diskspace_used() to fail.
> 
> Signed-off-by: Curt Wohlgemuth <curtw@google.com>

Added to the ext4 patch queue, thanks.

					- Ted

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2009-12-09  3:21 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2009-12-01 18:17 [PATCH] ext4: Remove blocks from inode prealloc list on failure Curt Wohlgemuth
2009-12-04  1:10 ` tytso
2009-12-04  9:43   ` Aneesh Kumar K.V
2009-12-04  9:46 ` Aneesh Kumar K.V
2009-12-04 19:14   ` Curt Wohlgemuth
2009-12-09  3:21     ` tytso

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