On Thu, 12 Apr 2007 17:21:22 +0200 Peter Zijlstra <[EMAIL PROTECTED]> wrote:
>
> Remove duplicate work in kill_bdev().
>
> It currently invalidates and then truncates the bdev's mapping.
> invalidate_mapping_pages() will opportunistically remove pages from the
> mapping. And truncate_inode_pages() will forcefully remove all pages.
>
> The only thing truncate doesn't do is flush the bh lrus. So do that
> explicitly.
> This avoids (very unlikely) but possible invalid lookup results if the
> same bdev is quickyl re-issued.
>
> Signed-off-by: Peter Zijlstra <[EMAIL PROTECTED]>
> ---
> fs/block_dev.c | 2 +-
> fs/buffer.c | 3 +--
> include/linux/buffer_head.h | 1 +
> 3 files changed, 3 insertions(+), 3 deletions(-)
>
> Index: linux-2.6/fs/block_dev.c
> ===================================================================
> --- linux-2.6.orig/fs/block_dev.c 2007-04-12 16:01:13.000000000 +0200
> +++ linux-2.6/fs/block_dev.c 2007-04-12 16:20:14.000000000 +0200
> @@ -61,7 +61,7 @@ static sector_t max_block(struct block_d
> /* Kill _all_ buffers, dirty or not.. */
> static void kill_bdev(struct block_device *bdev)
> {
> - invalidate_bdev(bdev);
> + invalidate_bh_lrus();
> truncate_inode_pages(bdev->bd_inode->i_mapping, 0);
> }
Fair enough, thanks.
The check for mapping->nr_pages != 0 was added to invalidate_bdev() to
avoid unpleasant IPI-induced stalls when large ia64 machines poll their
CDROM drives for media. I don't know if kill_bdev() gets called on the
probe-a-cdrom path, but we might as well put
if (bdev->bd_inode->i_mapping->nr_pages == 0)
return;
into kill_bdev(). I'll make that change.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
