linux-kernel - Re: [PATCH 1/4] mm: exporting account_page

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 20 Aug 2010 17:39:51 +0800
From:	Wu Fengguang <fengguang.wu@...el.com>
To:	Michael Rubin <mrubin@...gle.com>, Sage Weil <sage@...dream.net>
Cc:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-fsdevel@...r.kernel.org" <linux-fsdevel@...r.kernel.org>,
	"linux-mm@...ck.org" <linux-mm@...ck.org>,
	"jack@...e.cz" <jack@...e.cz>, "riel@...hat.com" <riel@...hat.com>,
	"akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
	"david@...morbit.com" <david@...morbit.com>,
	"npiggin@...nel.dk" <npiggin@...nel.dk>, "hch@....de" <hch@....de>,
	"axboe@...nel.dk" <axboe@...nel.dk>
Subject: Re: [PATCH 1/4] mm: exporting account_page_dirty

Sage,

This is actually a bug fix for ceph, which missed the task_dirty_inc()
call in account_page_dirty().

Reviewed-by: Wu Fengguang <fengguang.wu@...el.com>

On Fri, Aug 20, 2010 at 05:31:26PM +0800, Michael Rubin wrote:
> This allows code outside of the mm core to safely manipulate page state
> and not worry about the other accounting. Not using these routines means
> that some code will lose track of the accounting and we get bugs. This
> has happened once already.
> 
> Signed-off-by: Michael Rubin <mrubin@...gle.com>
> ---
>  fs/ceph/addr.c      |    8 +-------
>  mm/page-writeback.c |    1 +
>  2 files changed, 2 insertions(+), 7 deletions(-)
> 
> diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
> index 5598a0d..420d469 100644
> --- a/fs/ceph/addr.c
> +++ b/fs/ceph/addr.c
> @@ -105,13 +105,7 @@ static int ceph_set_page_dirty(struct page *page)
>  	spin_lock_irq(&mapping->tree_lock);
>  	if (page->mapping) {	/* Race with truncate? */
>  		WARN_ON_ONCE(!PageUptodate(page));
> -
> -		if (mapping_cap_account_dirty(mapping)) {
> -			__inc_zone_page_state(page, NR_FILE_DIRTY);
> -			__inc_bdi_stat(mapping->backing_dev_info,
> -					BDI_RECLAIMABLE);
> -			task_io_account_write(PAGE_CACHE_SIZE);
> -		}
> +		account_page_dirtied(page, page->mapping);
>  		radix_tree_tag_set(&mapping->page_tree,
>  				page_index(page), PAGECACHE_TAG_DIRTY);
>  
> diff --git a/mm/page-writeback.c b/mm/page-writeback.c
> index 7262aac..9d07a8d 100644
> --- a/mm/page-writeback.c
> +++ b/mm/page-writeback.c
> @@ -1131,6 +1131,7 @@ void account_page_dirtied(struct page *page, struct address_space *mapping)
>  		task_io_account_write(PAGE_CACHE_SIZE);
>  	}
>  }
> +EXPORT_SYMBOL(account_page_dirtied);
>  
>  /*
>   * For address_spaces which do not use buffers.  Just tag the page as dirty in
> -- 
> 1.7.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/