From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:53425 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752315AbcD1AR3 (ORCPT ); Wed, 27 Apr 2016 20:17:29 -0400 Subject: Patch "dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros" has been added to the 4.4-stable tree To: snitzer@redhat.com, ben@decadent.org.uk, gregkh@linuxfoundation.org Cc: , From: Date: Wed, 27 Apr 2016 17:17:16 -0700 Message-ID: <1461802636232243@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: dm-cache-metadata-fix-read_lock-macros-and-cleanup-write_lock-macros.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 9567366fefddeaea4ed1d713270535d93a3b3c76 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Tue, 12 Apr 2016 12:14:46 -0400 Subject: dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros From: Mike Snitzer commit 9567366fefddeaea4ed1d713270535d93a3b3c76 upstream. The READ_LOCK macro was incorrectly returning -EINVAL if dm_bm_is_read_only() was true -- it will always be true once the cache metadata transitions to read-only by dm_cache_metadata_set_read_only(). Wrap READ_LOCK and WRITE_LOCK multi-statement macros in do {} while(0). Also, all accesses of the 'cmd' argument passed to these related macros are now encapsulated in parenthesis. A follow-up patch can be developed to eliminate the use of macros in favor of pure C code. Avoiding that now given that this needs to apply to stable@. Reported-by: Ben Hutchings Signed-off-by: Mike Snitzer Fixes: d14fcf3dd79 ("dm cache: make sure every metadata function checks fail_io") Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-cache-metadata.c | 64 +++++++++++++++++++++++++---------------- 1 file changed, 40 insertions(+), 24 deletions(-) --- a/drivers/md/dm-cache-metadata.c +++ b/drivers/md/dm-cache-metadata.c @@ -867,39 +867,55 @@ static int blocks_are_unmapped_or_clean( return 0; } -#define WRITE_LOCK(cmd) \ - down_write(&cmd->root_lock); \ - if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \ - up_write(&cmd->root_lock); \ - return -EINVAL; \ +static bool cmd_write_lock(struct dm_cache_metadata *cmd) +{ + down_write(&cmd->root_lock); + if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { + up_write(&cmd->root_lock); + return false; } + return true; +} -#define WRITE_LOCK_VOID(cmd) \ - down_write(&cmd->root_lock); \ - if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \ - up_write(&cmd->root_lock); \ - return; \ - } +#define WRITE_LOCK(cmd) \ + do { \ + if (!cmd_write_lock((cmd))) \ + return -EINVAL; \ + } while(0) + +#define WRITE_LOCK_VOID(cmd) \ + do { \ + if (!cmd_write_lock((cmd))) \ + return; \ + } while(0) #define WRITE_UNLOCK(cmd) \ - up_write(&cmd->root_lock) + up_write(&(cmd)->root_lock) -#define READ_LOCK(cmd) \ - down_read(&cmd->root_lock); \ - if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \ - up_read(&cmd->root_lock); \ - return -EINVAL; \ +static bool cmd_read_lock(struct dm_cache_metadata *cmd) +{ + down_write(&cmd->root_lock); + if (cmd->fail_io) { + up_write(&cmd->root_lock); + return false; } + return true; +} -#define READ_LOCK_VOID(cmd) \ - down_read(&cmd->root_lock); \ - if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { \ - up_read(&cmd->root_lock); \ - return; \ - } +#define READ_LOCK(cmd) \ + do { \ + if (!cmd_read_lock((cmd))) \ + return -EINVAL; \ + } while(0) + +#define READ_LOCK_VOID(cmd) \ + do { \ + if (!cmd_read_lock((cmd))) \ + return; \ + } while(0) #define READ_UNLOCK(cmd) \ - up_read(&cmd->root_lock) + up_read(&(cmd)->root_lock) int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size) { Patches currently in stable-queue which might be from snitzer@redhat.com are queue-4.4/dm-cache-metadata-fix-cmd_read_lock-acquiring-write-lock.patch queue-4.4/dm-cache-metadata-fix-read_lock-macros-and-cleanup-write_lock-macros.patch