From 3c68d44a2b49a0ac9165faa9c191e1e618c8a8d5 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 6 Feb 2017 10:51:03 -0800 Subject: [PATCH] xfs: allocate direct I/O COW blocks in iomap_begin Instead of preallocating all the required COW blocks in the high-level write code do it inside the iomap code, like we do for all other I/O. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_file.c | 8 --- fs/xfs/xfs_iomap.c | 31 +++++------ fs/xfs/xfs_reflink.c | 146 +++++++++++++++++++-------------------------------- fs/xfs/xfs_reflink.h | 4 +- fs/xfs/xfs_trace.h | 2 - 5 files changed, 68 insertions(+), 123 deletions(-) diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 2a695a8..086440e 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -561,14 +561,6 @@ xfs_file_dio_aio_write( } trace_xfs_file_direct_write(ip, count, iocb->ki_pos); - - /* If this is a block-aligned directio CoW, remap immediately. */ - if (xfs_is_reflink_inode(ip) && !unaligned_io) { - ret = xfs_reflink_allocate_cow_range(ip, iocb->ki_pos, count); - if (ret) - goto out; - } - ret = iomap_dio_rw(iocb, from, &xfs_iomap_ops, xfs_dio_write_end_io); out: xfs_iunlock(ip, iolock); diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 06bfc82..e0bc290 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -995,37 +995,31 @@ xfs_file_iomap_begin( offset_fsb = XFS_B_TO_FSBT(mp, offset); end_fsb = XFS_B_TO_FSB(mp, offset + length); - if (xfs_is_reflink_inode(ip) && - (flags & IOMAP_WRITE) && (flags & IOMAP_DIRECT)) { - shared = xfs_reflink_find_cow_mapping(ip, offset, &imap); - if (shared) { - xfs_iunlock(ip, lockmode); - goto alloc_done; - } - ASSERT(!isnullstartblock(imap.br_startblock)); - } - error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap, &nimaps, 0); if (error) goto out_unlock; - if ((flags & IOMAP_REPORT) || - (xfs_is_reflink_inode(ip) && - (flags & IOMAP_WRITE) && (flags & IOMAP_DIRECT))) { + if (flags & IOMAP_REPORT) { /* Trim the mapping to the nearest shared extent boundary. */ error = xfs_reflink_trim_around_shared(ip, &imap, &shared, &trimmed); if (error) goto out_unlock; - - ASSERT((flags & IOMAP_REPORT) || !shared); } if ((flags & (IOMAP_WRITE | IOMAP_ZERO)) && xfs_is_reflink_inode(ip)) { - error = xfs_reflink_reserve_cow(ip, &imap, &shared); - if (error) - goto out_unlock; + if (flags & IOMAP_DIRECT) { + /* may drop and re-acquire the ilock */ + error = xfs_reflink_allocate_cow(ip, &imap, &shared, + &lockmode); + if (error) + goto out_unlock; + } else { + error = xfs_reflink_reserve_cow(ip, &imap, &shared); + if (error) + goto out_unlock; + } end_fsb = imap.br_startoff + imap.br_blockcount; length = XFS_FSB_TO_B(mp, end_fsb) - offset; @@ -1054,7 +1048,6 @@ xfs_file_iomap_begin( if (error) return error; -alloc_done: iomap->flags = IOMAP_F_NEW; trace_xfs_iomap_alloc(ip, offset, length, 0, &imap); } else { diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index 9bba084..1f61877 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -382,74 +382,75 @@ xfs_reflink_convert_cow( } /* Allocate all CoW reservations covering a range of blocks in a file. */ -static int -__xfs_reflink_allocate_cow( +int +xfs_reflink_allocate_cow( struct xfs_inode *ip, - xfs_fileoff_t *offset_fsb, - xfs_fileoff_t end_fsb) + struct xfs_bmbt_irec *imap, + bool *shared, + uint *lockmode) { struct xfs_mount *mp = ip->i_mount; - struct xfs_bmbt_irec imap, got; + xfs_fileoff_t offset_fsb = imap->br_startoff; + xfs_filblks_t count_fsb = imap->br_blockcount; + struct xfs_bmbt_irec got; struct xfs_defer_ops dfops; - struct xfs_trans *tp; + struct xfs_trans *tp = NULL; xfs_fsblock_t first_block; - int nimaps, error, lockmode; - bool shared, trimmed; + int nimaps, error = 0; + bool trimmed; xfs_filblks_t resaligned; - xfs_extlen_t resblks; + xfs_extlen_t resblks = 0; xfs_extnum_t idx; - resaligned = xfs_aligned_fsb_count(*offset_fsb, end_fsb - *offset_fsb, - xfs_get_cowextsz_hint(ip)); - resblks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned); - - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp); - if (error) - return error; - - lockmode = XFS_ILOCK_EXCL; - xfs_ilock(ip, lockmode); +retry: + ASSERT(xfs_is_reflink_inode(ip)); + ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED)); /* * Even if the extent is not shared we might have a preallocation for * it in the COW fork. If so use it. */ - if (xfs_iext_lookup_extent(ip, ip->i_cowfp, *offset_fsb, &idx, &got) && - got.br_startoff <= *offset_fsb) { + if (xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &idx, &got) && + got.br_startoff <= offset_fsb) { + *shared = true; + /* If we have a real allocation in the COW fork we're done. */ if (!isnullstartblock(got.br_startblock)) { - xfs_trim_extent(&got, *offset_fsb, - end_fsb - *offset_fsb); - *offset_fsb = got.br_startoff + got.br_blockcount; - goto out_trans_cancel; + xfs_trim_extent(&got, offset_fsb, count_fsb); + *imap = got; + goto convert; } + + xfs_trim_extent(imap, got.br_startoff, got.br_blockcount); } else { - nimaps = 1; - error = xfs_bmapi_read(ip, *offset_fsb, end_fsb - *offset_fsb, - &imap, &nimaps, 0); - if (error) - goto out_trans_cancel; - ASSERT(nimaps == 1); + error = xfs_reflink_trim_around_shared(ip, imap, shared, &trimmed); + if (error || !*shared) + goto out; + } - /* Trim the mapping to the nearest shared extent boundary. */ - error = xfs_reflink_trim_around_shared(ip, &imap, &shared, - &trimmed); - if (error) - goto out_trans_cancel; + if (!tp) { + resaligned = xfs_aligned_fsb_count(imap->br_startoff, + imap->br_blockcount, xfs_get_cowextsz_hint(ip)); + resblks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned); - if (!shared) { - *offset_fsb = imap.br_startoff + imap.br_blockcount; - goto out_trans_cancel; - } + xfs_iunlock(ip, *lockmode); + error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp); + *lockmode = XFS_ILOCK_EXCL; + xfs_ilock(ip, *lockmode); - *offset_fsb = imap.br_startoff; - end_fsb = imap.br_startoff + imap.br_blockcount; + if (error) + return error; + + error = xfs_qm_dqattach_locked(ip, 0); + if (error) + goto out; + goto retry; } error = xfs_trans_reserve_quota_nblks(tp, ip, resblks, 0, XFS_QMOPT_RES_REGBLKS); if (error) - goto out_trans_cancel; + goto out; xfs_trans_ijoin(tp, ip, 0); @@ -457,9 +458,9 @@ __xfs_reflink_allocate_cow( nimaps = 1; /* Allocate the entire reservation as unwritten blocks. */ - error = xfs_bmapi_write(tp, ip, *offset_fsb, end_fsb - *offset_fsb, + error = xfs_bmapi_write(tp, ip, imap->br_startoff, imap->br_blockcount, XFS_BMAPI_COWFORK | XFS_BMAPI_PREALLOC, &first_block, - resblks, &imap, &nimaps, &dfops); + resblks, imap, &nimaps, &dfops); if (error) goto out_bmap_cancel; @@ -470,57 +471,18 @@ __xfs_reflink_allocate_cow( error = xfs_trans_commit(tp); if (error) - goto out_unlock; - - *offset_fsb = imap.br_startoff + imap.br_blockcount; - -out_unlock: - xfs_iunlock(ip, lockmode); - return error; - + return error; +convert: + return xfs_reflink_convert_cow_extent(ip, imap, offset_fsb, count_fsb, + &dfops); out_bmap_cancel: xfs_defer_cancel(&dfops); xfs_trans_unreserve_quota_nblks(tp, ip, (long)resblks, 0, XFS_QMOPT_RES_REGBLKS); -out_trans_cancel: - xfs_trans_cancel(tp); - goto out_unlock; -} - -/* Allocate all CoW reservations covering a part of a file. */ -int -xfs_reflink_allocate_cow_range( - struct xfs_inode *ip, - xfs_off_t offset, - xfs_off_t count) -{ - struct xfs_mount *mp = ip->i_mount; - xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); - xfs_fileoff_t end_fsb = XFS_B_TO_FSB(mp, offset + count); - int error; - - ASSERT(xfs_is_reflink_inode(ip)); - - trace_xfs_reflink_allocate_cow_range(ip, offset, count); - - /* - * Make sure that the dquots are there. - */ - error = xfs_qm_dqattach(ip, 0); - if (error) - return error; - - while (offset_fsb < end_fsb) { - error = __xfs_reflink_allocate_cow(ip, &offset_fsb, end_fsb); - if (error) { - trace_xfs_reflink_allocate_cow_range_error(ip, error, - _RET_IP_); - return error; - } - } - - /* Convert the CoW extents to regular. */ - return xfs_reflink_convert_cow(ip, offset, count); +out: + if (tp) + xfs_trans_cancel(tp); + return error; } /* diff --git a/fs/xfs/xfs_reflink.h b/fs/xfs/xfs_reflink.h index 1583c47..33ac9b8 100644 --- a/fs/xfs/xfs_reflink.h +++ b/fs/xfs/xfs_reflink.h @@ -28,8 +28,8 @@ extern int xfs_reflink_trim_around_shared(struct xfs_inode *ip, extern int xfs_reflink_reserve_cow(struct xfs_inode *ip, struct xfs_bmbt_irec *imap, bool *shared); -extern int xfs_reflink_allocate_cow_range(struct xfs_inode *ip, - xfs_off_t offset, xfs_off_t count); +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, diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index b654893..fb7555e 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -3247,7 +3247,6 @@ DEFINE_INODE_IREC_EVENT(xfs_reflink_cow_enospc); DEFINE_INODE_IREC_EVENT(xfs_reflink_convert_cow); DEFINE_RW_EVENT(xfs_reflink_reserve_cow); -DEFINE_RW_EVENT(xfs_reflink_allocate_cow_range); DEFINE_SIMPLE_IO_EVENT(xfs_reflink_bounce_dio_write); DEFINE_IOMAP_EVENT(xfs_reflink_find_cow_mapping); @@ -3257,7 +3256,6 @@ DEFINE_SIMPLE_IO_EVENT(xfs_reflink_cancel_cow_range); DEFINE_SIMPLE_IO_EVENT(xfs_reflink_end_cow); DEFINE_INODE_IREC_EVENT(xfs_reflink_cow_remap); -DEFINE_INODE_ERROR_EVENT(xfs_reflink_allocate_cow_range_error); DEFINE_INODE_ERROR_EVENT(xfs_reflink_cancel_cow_range_error); DEFINE_INODE_ERROR_EVENT(xfs_reflink_end_cow_error); -- 2.7.4