Re: [PATCH] fix data bug in device-mapping invalidation

[Stephen Lord <lord@sgi.com>]

Christoph Hellwig wrote:

>Currently pagebuf_lock_disable() calls destroy_buffers() and 
>truncate_inode_pages() unconditionally.  For the post 2.4.13 case
>where the pagebuf modules sits ontop of the blockdevice mapping
>this could cause incore data corruption for other openers of that
>device (xfsdump?).  The fix is to completly remove the calls,
>blkdev_put does them when the last opener finished.
>
>Keep the code for the pre 2.4.13 case as those use their own mapping.
>Patch is ontop of my last patch, but the bug is present even without it.
>
>--- linux/fs/xfs/pagebuf/page_buf_locking.c.~hch~	Sat May  4 13:46:55 2002
>+++ linux/fs/xfs/pagebuf/page_buf_locking.c	Sat May  4 13:48:33 2002
>@@ -324,8 +324,10 @@
> pagebuf_lock_disable(			/* disable buffer locking	*/
> 		     pb_target_t *target)  /* inode for buffers	        */
> {
>+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,4,13))
> 	destroy_buffers(target->pbr_device);
> 	truncate_inode_pages(PBT_ADDR_SPACE(target), 0LL);
>+#endif
> 	bdput(target->pbr_bdev);
> 	kmem_cache_free(pagebuf_target_cache, target);
> 
>
Thanks Christoph, this and your other patches are in my queue - I am 
bogged down
in an I/O path rewrite at the moment, amongst other things.

Steve