From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jaegeuk Kim Subject: [PATCH 6/6] f2fs: avoid double lock for cp_rwsem Date: Sun, 21 Dec 2014 08:35:23 -0800 Message-ID: <1419179723-3234-6-git-send-email-jaegeuk@kernel.org> References: <1419179723-3234-1-git-send-email-jaegeuk@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1Y2jTp-0006QU-DS for linux-f2fs-devel@lists.sourceforge.net; Sun, 21 Dec 2014 16:35:41 +0000 Received: from mail.kernel.org ([198.145.19.201]) by sog-mx-2.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1Y2jTo-0001j6-N2 for linux-f2fs-devel@lists.sourceforge.net; Sun, 21 Dec 2014 16:35:41 +0000 In-Reply-To: <1419179723-3234-1-git-send-email-jaegeuk@kernel.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Cc: Jaegeuk Kim The __f2fs_add_link is covered by cp_rwsem all the time. This calls init_inode_metadata, which conducts some acl operations including memory allocation with GFP_KERNEL previously. But, under memory pressure, f2fs_write_data_page can be called, which also grabs cp_mutex too. Basically, it's safe since down_read was used in both of cases, but it'd better avoid this situation in advance. Signed-off-by: Jaegeuk Kim --- fs/f2fs/acl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/f2fs/acl.c b/fs/f2fs/acl.c index 1ccb26b..7f12d28 100644 --- a/fs/f2fs/acl.c +++ b/fs/f2fs/acl.c @@ -62,7 +62,7 @@ static struct posix_acl *f2fs_acl_from_disk(const char *value, size_t size) if (count == 0) return NULL; - acl = posix_acl_alloc(count, GFP_KERNEL); + acl = posix_acl_alloc(count, GFP_NOFS); if (!acl) return ERR_PTR(-ENOMEM); @@ -116,7 +116,7 @@ static void *f2fs_acl_to_disk(const struct posix_acl *acl, size_t *size) int i; f2fs_acl = kmalloc(sizeof(struct f2fs_acl_header) + acl->a_count * - sizeof(struct f2fs_acl_entry), GFP_KERNEL); + sizeof(struct f2fs_acl_entry), GFP_NOFS); if (!f2fs_acl) return ERR_PTR(-ENOMEM); -- 2.1.1 ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk