From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f180.google.com ([209.85.192.180]:35088 "EHLO mail-pf0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751971AbcKRUEk (ORCPT ); Fri, 18 Nov 2016 15:04:40 -0500 Received: by mail-pf0-f180.google.com with SMTP id i88so55880397pfk.2 for ; Fri, 18 Nov 2016 12:04:40 -0800 (PST) Date: Fri, 18 Nov 2016 12:04:38 -0800 From: Omar Sandoval To: Christoph Hellwig Cc: linux-btrfs@vger.kernel.org Subject: Re: [PATCH 6/9] btrfs: calculate end of bio offset properly Message-ID: <20161118200438.GF19038@vader.DHCP.thefacebook.com> References: <1479300736-9724-1-git-send-email-hch@lst.de> <1479300736-9724-7-git-send-email-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1479300736-9724-7-git-send-email-hch@lst.de> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Wed, Nov 16, 2016 at 01:52:13PM +0100, Christoph Hellwig wrote: > Use the bvec offset and len members to prepare for multipage bvecs. > > Signed-off-by: Christoph Hellwig > --- > fs/btrfs/compression.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c > index 8618ac3..27e9feb 100644 > --- a/fs/btrfs/compression.c > +++ b/fs/btrfs/compression.c > @@ -445,6 +445,13 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start, > return 0; > } > > +static u64 bio_end_offset(struct bio *bio) > +{ > + struct bio_vec *last = &bio->bi_io_vec[bio->bi_vcnt - 1]; > + > + return page_offset(last->bv_page) + last->bv_len - last->bv_offset; Why is this minus bv_offset and not plus? Am I misunderstanding bv_offset? > +} > + > static noinline int add_ra_bio_pages(struct inode *inode, > u64 compressed_end, > struct compressed_bio *cb) > @@ -463,8 +470,7 @@ static noinline int add_ra_bio_pages(struct inode *inode, > u64 end; > int misses = 0; > > - page = cb->orig_bio->bi_io_vec[cb->orig_bio->bi_vcnt - 1].bv_page; > - last_offset = (page_offset(page) + PAGE_SIZE); > + last_offset = bio_end_offset(cb->orig_bio); > em_tree = &BTRFS_I(inode)->extent_tree; > tree = &BTRFS_I(inode)->io_tree; > > -- > 2.1.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Omar