From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: [PATCH 24/25] xfs: support returning partial reflink results From: "Darrick J. Wong" To: david@fromorbit.com, darrick.wong@oracle.com Cc: sandeen@redhat.com, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, ocfs2-devel@oss.oracle.com Date: Wed, 10 Oct 2018 21:15:19 -0700 Message-ID: <153923131946.5546.5209673711907751253.stgit@magnolia> In-Reply-To: <153923113649.5546.9840926895953408273.stgit@magnolia> References: <153923113649.5546.9840926895953408273.stgit@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: From: Darrick J. Wong Back when the XFS reflink code only supported clone_file_range, we were only able to return zero or negative error codes to userspace. However, now that copy_file_range (which returns bytes copied) can use XFS' clone_file_range, we have the opportunity to return partial results. For example, if userspace sends a 1GB clone request and we run out of space halfway through, we at least can tell userspace that we completed 512M of that request like a regular write. Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_file.c | 5 +---- fs/xfs/xfs_reflink.c | 19 ++++++++++++++----- fs/xfs/xfs_reflink.h | 2 +- 3 files changed, 16 insertions(+), 10 deletions(-) diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index bc9e94bcb7a3..b2b15b8dc4a1 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -928,14 +928,11 @@ xfs_file_remap_range( loff_t len, unsigned int remap_flags) { - int ret; - if (!remap_check_flags(remap_flags, RFR_SAME_DATA)) return -EINVAL; - ret = xfs_reflink_remap_range(file_in, pos_in, file_out, pos_out, + return xfs_reflink_remap_range(file_in, pos_in, file_out, pos_out, len, remap_flags); - return ret < 0 ? ret : len; } STATIC int diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index e1592e751cc2..12a1fe92454e 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -1123,6 +1123,7 @@ xfs_reflink_remap_blocks( struct xfs_inode *dest, xfs_fileoff_t destoff, xfs_filblks_t len, + xfs_filblks_t *remapped, xfs_off_t new_isize) { struct xfs_bmbt_irec imap; @@ -1130,6 +1131,7 @@ xfs_reflink_remap_blocks( int error = 0; xfs_filblks_t range_len; + *remapped = 0; /* drange = (destoff, destoff + len); srange = (srcoff, srcoff + len) */ while (len) { uint lock_mode; @@ -1168,6 +1170,7 @@ xfs_reflink_remap_blocks( srcoff += range_len; destoff += range_len; len -= range_len; + *remapped += range_len; } return 0; @@ -1391,7 +1394,7 @@ xfs_reflink_remap_prep( /* * Link a range of blocks from one file to another. */ -int +loff_t xfs_reflink_remap_range( struct file *file_in, loff_t pos_in, @@ -1406,9 +1409,9 @@ xfs_reflink_remap_range( struct xfs_inode *dest = XFS_I(inode_out); struct xfs_mount *mp = src->i_mount; xfs_fileoff_t sfsbno, dfsbno; - xfs_filblks_t fsblen; + xfs_filblks_t fsblen, remapped = 0; xfs_extlen_t cowextsize; - ssize_t ret; + int ret; if (!xfs_sb_version_hasreflink(&mp->m_sb)) return -EOPNOTSUPP; @@ -1424,11 +1427,17 @@ xfs_reflink_remap_range( trace_xfs_reflink_remap_range(src, pos_in, len, dest, pos_out); + if (len == 0) { + ret = 0; + goto out_unlock; + } + dfsbno = XFS_B_TO_FSBT(mp, pos_out); sfsbno = XFS_B_TO_FSBT(mp, pos_in); fsblen = XFS_B_TO_FSB(mp, len); ret = xfs_reflink_remap_blocks(src, sfsbno, dest, dfsbno, fsblen, - pos_out + len); + &remapped, pos_out + len); + remapped = min_t(int64_t, len, XFS_FSB_TO_B(mp, remapped)); if (ret) goto out_unlock; @@ -1451,7 +1460,7 @@ xfs_reflink_remap_range( xfs_reflink_remap_unlock(file_in, file_out); if (ret) trace_xfs_reflink_remap_range_error(dest, ret, _RET_IP_); - return ret; + return remapped > 0 ? remapped : ret; } /* diff --git a/fs/xfs/xfs_reflink.h b/fs/xfs/xfs_reflink.h index c3c46c276fe1..cbc26ff79a8f 100644 --- a/fs/xfs/xfs_reflink.h +++ b/fs/xfs/xfs_reflink.h @@ -27,7 +27,7 @@ extern int xfs_reflink_cancel_cow_range(struct xfs_inode *ip, xfs_off_t offset, extern int xfs_reflink_end_cow(struct xfs_inode *ip, xfs_off_t offset, xfs_off_t count); extern int xfs_reflink_recover_cow(struct xfs_mount *mp); -extern int xfs_reflink_remap_range(struct file *file_in, loff_t pos_in, +extern loff_t xfs_reflink_remap_range(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, loff_t len, unsigned int remap_flags); extern int xfs_reflink_inode_has_shared_extents(struct xfs_trans *tp,