From: Jan Kara Subject: Re: [RFC] ext4: fix a BUG in ext4_mpage_readpages() Date: Thu, 5 Nov 2015 16:40:31 +0100 Message-ID: <20151105154031.GC23628@quack.suse.cz> References: <1446623914-9367-1-git-send-email-yalin.wang2010@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: tytso@mit.edu, adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org To: yalin wang Return-path: Content-Disposition: inline In-Reply-To: <1446623914-9367-1-git-send-email-yalin.wang2010@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Wed 04-11-15 15:58:34, yalin wang wrote: > The last block should be the total read pages last block, > need adjust the block number when caculate every page. > > Signed-off-by: yalin wang > --- > fs/ext4/readpage.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c > index 5dc5e95..d20c39d 100644 > --- a/fs/ext4/readpage.c > +++ b/fs/ext4/readpage.c > @@ -174,7 +174,7 @@ int ext4_mpage_readpages(struct address_space *mapping, > goto confused; > > block_in_file = (sector_t)page->index << (PAGE_CACHE_SHIFT - blkbits); > - last_block = block_in_file + nr_pages * blocks_per_page; > + last_block = block_in_file + (nr_pages - page_idx) * blocks_per_page; I don't think your patch is correct. The for loop decrements nr_pages at each iteration so the original code looks fine... Or which problems do you observe? Honza > last_block_in_file = (i_size_read(inode) + blocksize - 1) >> blkbits; > if (last_block > last_block_in_file) > last_block = last_block_in_file; > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Jan Kara SUSE Labs, CR