Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932172AbZGABQD (ORCPT ); Tue, 30 Jun 2009 21:16:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761603AbZGAAfy (ORCPT ); Tue, 30 Jun 2009 20:35:54 -0400 Received: from kroah.org ([198.145.64.141]:60709 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761587AbZGAAfo (ORCPT ); Tue, 30 Jun 2009 20:35:44 -0400 X-Mailbox-Line: From gregkh@mini.kroah.org Tue Jun 30 17:24:43 2009 Message-Id: <20090701002442.919795661@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Tue, 30 Jun 2009 17:24:28 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Mikulas Patocka , Alasdair G Kergon Subject: [patch 099/108] dm: use i_size_read References: <20090701002249.937782934@mini.kroah.org> Content-Disposition: inline; filename=dm-use-i_size_read.patch In-Reply-To: <20090701002838.GA7100@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2433 Lines: 58 2.6.30-stable review patch. If anyone has any objections, please let us know. ------------------ From: Mikulas Patocka commit 5657e8fa45cf230df278040c420fb80e06309d8f upstream. Use i_size_read() instead of reading i_size. If someone changes the size of the device simultaneously, i_size_read is guaranteed to return a valid value (either the old one or the new one). i_size can return some intermediate invalid value (on 32-bit computers with 64-bit i_size, the reads to both halves of i_size can be interleaved with updates to i_size, resulting in garbage being returned). Signed-off-by: Mikulas Patocka Signed-off-by: Alasdair G Kergon Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-exception-store.h | 2 +- drivers/md/dm-log.c | 2 +- drivers/md/dm-table.c | 3 ++- 3 files changed, 4 insertions(+), 3 deletions(-) --- a/drivers/md/dm-exception-store.h +++ b/drivers/md/dm-exception-store.h @@ -156,7 +156,7 @@ static inline void dm_consecutive_chunk_ */ static inline sector_t get_dev_size(struct block_device *bdev) { - return bdev->bd_inode->i_size >> SECTOR_SHIFT; + return i_size_read(bdev->bd_inode) >> SECTOR_SHIFT; } static inline chunk_t sector_to_chunk(struct dm_exception_store *store, --- a/drivers/md/dm-log.c +++ b/drivers/md/dm-log.c @@ -415,7 +415,7 @@ static int create_log_context(struct dm_ buf_size = dm_round_up((LOG_OFFSET << SECTOR_SHIFT) + bitset_size, ti->limits.hardsect_size); - if (buf_size > dev->bdev->bd_inode->i_size) { + if (buf_size > i_size_read(dev->bdev->bd_inode)) { DMWARN("log device %s too small: need %llu bytes", dev->name, (unsigned long long)buf_size); kfree(lc); --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -387,7 +387,8 @@ static void close_dev(struct dm_dev_inte static int check_device_area(struct dm_dev_internal *dd, sector_t start, sector_t len) { - sector_t dev_size = dd->dm_dev.bdev->bd_inode->i_size >> SECTOR_SHIFT; + sector_t dev_size = i_size_read(dd->dm_dev.bdev->bd_inode) >> + SECTOR_SHIFT; if (!dev_size) return 1; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/