From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 31 May 2018 09:46:44 -0400 From: Brian Foster To: Christoph Hellwig Cc: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 08/18] xfs: remove xfs_reflink_find_cow_mapping Message-ID: <20180531134643.GB2997@bfoster.bfoster> References: <20180530100013.31358-1-hch@lst.de> <20180530100013.31358-9-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180530100013.31358-9-hch@lst.de> Sender: owner-linux-mm@kvack.org List-ID: On Wed, May 30, 2018 at 12:00:03PM +0200, Christoph Hellwig wrote: > We only have one caller left, and open coding the simple extent list > lookup in it allows us to make the code both more understandable and > reuse calculations and variables already present. > > Signed-off-by: Christoph Hellwig > --- Reviewed-by: Brian Foster > fs/xfs/xfs_aops.c | 17 ++++++++++++----- > fs/xfs/xfs_reflink.c | 30 ------------------------------ > fs/xfs/xfs_reflink.h | 2 -- > fs/xfs/xfs_trace.h | 1 - > 4 files changed, 12 insertions(+), 38 deletions(-) > > diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c > index 8cc41a786b5e..e2671b223409 100644 > --- a/fs/xfs/xfs_aops.c > +++ b/fs/xfs/xfs_aops.c > @@ -385,6 +385,7 @@ xfs_map_blocks( > ssize_t count = i_blocksize(inode); > xfs_fileoff_t offset_fsb, end_fsb; > int whichfork = XFS_DATA_FORK; > + struct xfs_iext_cursor icur; > int error = 0; > int nimaps = 1; > > @@ -396,8 +397,18 @@ xfs_map_blocks( > (ip->i_df.if_flags & XFS_IFEXTENTS)); > ASSERT(offset <= mp->m_super->s_maxbytes); > > + if (offset > mp->m_super->s_maxbytes - count) > + count = mp->m_super->s_maxbytes - offset; > + end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count); > + offset_fsb = XFS_B_TO_FSBT(mp, offset); > + > + /* > + * Check if this is offset is covered by a COW extents, and if yes use > + * it directly instead of looking up anything in the data fork. > + */ > if (xfs_is_reflink_inode(ip) && > - xfs_reflink_find_cow_mapping(ip, offset, imap)) { > + xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &icur, imap) && > + imap->br_startoff <= offset_fsb) { > xfs_iunlock(ip, XFS_ILOCK_SHARED); > /* > * Truncate can race with writeback since writeback doesn't > @@ -417,10 +428,6 @@ xfs_map_blocks( > goto allocate_blocks; > } > > - if (offset > mp->m_super->s_maxbytes - count) > - count = mp->m_super->s_maxbytes - offset; > - end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count); > - offset_fsb = XFS_B_TO_FSBT(mp, offset); > error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, > imap, &nimaps, XFS_BMAPI_ENTIRE); > if (!nimaps) { > diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c > index 713e857d9ffa..8e5eb8e70c89 100644 > --- a/fs/xfs/xfs_reflink.c > +++ b/fs/xfs/xfs_reflink.c > @@ -484,36 +484,6 @@ xfs_reflink_allocate_cow( > return error; > } > > -/* > - * Find the CoW reservation for a given byte offset of a file. > - */ > -bool > -xfs_reflink_find_cow_mapping( > - struct xfs_inode *ip, > - xfs_off_t offset, > - struct xfs_bmbt_irec *imap) > -{ > - struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); > - xfs_fileoff_t offset_fsb; > - struct xfs_bmbt_irec got; > - struct xfs_iext_cursor icur; > - > - ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED)); > - > - if (!xfs_is_reflink_inode(ip)) > - return false; > - offset_fsb = XFS_B_TO_FSBT(ip->i_mount, offset); > - if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &icur, &got)) > - return false; > - if (got.br_startoff > offset_fsb) > - return false; > - > - trace_xfs_reflink_find_cow_mapping(ip, offset, 1, XFS_IO_OVERWRITE, > - &got); > - *imap = got; > - return true; > -} > - > /* > * Trim an extent to end at the next CoW reservation past offset_fsb. > */ > diff --git a/fs/xfs/xfs_reflink.h b/fs/xfs/xfs_reflink.h > index 701487bab468..15a456492667 100644 > --- a/fs/xfs/xfs_reflink.h > +++ b/fs/xfs/xfs_reflink.h > @@ -32,8 +32,6 @@ extern int xfs_reflink_allocate_cow(struct xfs_inode *ip, > struct xfs_bmbt_irec *imap, bool *shared, uint *lockmode); > extern int xfs_reflink_convert_cow(struct xfs_inode *ip, xfs_off_t offset, > xfs_off_t count); > -extern bool xfs_reflink_find_cow_mapping(struct xfs_inode *ip, xfs_off_t offset, > - struct xfs_bmbt_irec *imap); > extern void xfs_reflink_trim_irec_to_next_cow(struct xfs_inode *ip, > xfs_fileoff_t offset_fsb, struct xfs_bmbt_irec *imap); > > diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h > index 9d4c4ca24fe6..ed8f774944ba 100644 > --- a/fs/xfs/xfs_trace.h > +++ b/fs/xfs/xfs_trace.h > @@ -3227,7 +3227,6 @@ DEFINE_INODE_IREC_EVENT(xfs_reflink_convert_cow); > DEFINE_RW_EVENT(xfs_reflink_reserve_cow); > > DEFINE_SIMPLE_IO_EVENT(xfs_reflink_bounce_dio_write); > -DEFINE_IOMAP_EVENT(xfs_reflink_find_cow_mapping); > DEFINE_INODE_IREC_EVENT(xfs_reflink_trim_irec); > > DEFINE_SIMPLE_IO_EVENT(xfs_reflink_cancel_cow_range); > -- > 2.17.0 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html