From 36adcbace24e99ed89ac5310a0e1c3890e551665 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 19 Oct 2019 09:09:44 -0700 Subject: [PATCH] xfs: fill out the srcmap in iomap_begin Replace our local hacks to report the source block in the main iomap with the proper scrmap reporting. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_iomap.c | 49 ++++++++++++++++++++++++------------------------- 1 file changed, 24 insertions(+), 25 deletions(-) diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 38e0b12..08c0f0a 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -527,7 +527,8 @@ xfs_file_iomap_begin_delay( loff_t offset, loff_t count, unsigned flags, - struct iomap *iomap) + struct iomap *iomap, + struct iomap *srcmap) { struct xfs_inode *ip = XFS_I(inode); struct xfs_mount *mp = ip->i_mount; @@ -721,11 +722,13 @@ found_imap: found_cow: xfs_iunlock(ip, XFS_ILOCK_EXCL); if (imap.br_startoff <= offset_fsb) { - /* ensure we only report blocks we have a reservation for */ - xfs_trim_extent(&imap, cmap.br_startoff, cmap.br_blockcount); - return xfs_bmbt_to_iomap(ip, iomap, &imap, IOMAP_F_SHARED); + error = xfs_bmbt_to_iomap(ip, srcmap, &imap, 0); + if (error) + return error; + } else { + xfs_trim_extent(&cmap, offset_fsb, + imap.br_startoff - offset_fsb); } - xfs_trim_extent(&cmap, offset_fsb, imap.br_startoff - offset_fsb); return xfs_bmbt_to_iomap(ip, iomap, &cmap, IOMAP_F_SHARED); out_unlock: @@ -933,7 +936,7 @@ xfs_file_iomap_begin( { struct xfs_inode *ip = XFS_I(inode); struct xfs_mount *mp = ip->i_mount; - struct xfs_bmbt_irec imap; + struct xfs_bmbt_irec imap, cmap; xfs_fileoff_t offset_fsb, end_fsb; int nimaps = 1, error = 0; bool shared = false; @@ -947,7 +950,7 @@ xfs_file_iomap_begin( !IS_DAX(inode) && !xfs_get_extsz_hint(ip)) { /* Reserve delalloc blocks for regular writeback. */ return xfs_file_iomap_begin_delay(inode, offset, length, flags, - iomap); + iomap, srcmap); } /* @@ -987,9 +990,6 @@ xfs_file_iomap_begin( * been done up front, so we don't need to do them here. */ if (xfs_is_cow_inode(ip)) { - struct xfs_bmbt_irec cmap; - bool directio = (flags & IOMAP_DIRECT); - /* if zeroing doesn't need COW allocation, then we are done. */ if ((flags & IOMAP_ZERO) && !needs_cow_for_zeroing(&imap, nimaps)) @@ -997,23 +997,11 @@ xfs_file_iomap_begin( /* may drop and re-acquire the ilock */ error = xfs_reflink_allocate_cow(ip, &imap, &cmap, &shared, - &lockmode, directio); + &lockmode, flags & IOMAP_DIRECT); if (error) goto out_unlock; - - /* - * For buffered writes we need to report the address of the - * previous block (if there was any) so that the higher level - * write code can perform read-modify-write operations; we - * won't need the CoW fork mapping until writeback. For direct - * I/O, which must be block aligned, we need to report the - * newly allocated address. If the data fork has a hole, copy - * the COW fork mapping to avoid allocating to the data fork. - */ - if (shared && - (directio || imap.br_startblock == HOLESTARTBLOCK)) - imap = cmap; - + if (shared) + goto out_found_cow; end_fsb = imap.br_startoff + imap.br_blockcount; length = XFS_FSB_TO_B(mp, end_fsb) - offset; } @@ -1074,6 +1062,17 @@ out_found: trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap); goto out_finish; +out_found_cow: + xfs_iunlock(ip, lockmode); + length = XFS_FSB_TO_B(mp, cmap.br_startoff + cmap.br_blockcount); + trace_xfs_iomap_found(ip, offset, length - offset, XFS_COW_FORK, &cmap); + if (imap.br_startblock != HOLESTARTBLOCK) { + error = xfs_bmbt_to_iomap(ip, srcmap, &imap, 0); + if (error) + return error; + } + return xfs_bmbt_to_iomap(ip, iomap, &cmap, IOMAP_F_SHARED); + out_unlock: xfs_iunlock(ip, lockmode); return error; -- 2.7.4