1 files changed, 164 insertions, 76 deletions

diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 3246815c24d6..cdbd342a5249 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -49,8 +49,6 @@
 #include "xfs_alloc.h"
 #include "xfs_quota_defs.h"
 #include "xfs_quota.h"
-#include "xfs_btree.h"
-#include "xfs_bmap_btree.h"
 #include "xfs_reflink.h"
 #include "xfs_iomap.h"
 #include "xfs_rmap_btree.h"
@@ -273,7 +271,7 @@ xfs_reflink_reserve_cow(
 	struct xfs_bmbt_irec	got;
 	int			error = 0;
 	bool			eof = false, trimmed;
-	xfs_extnum_t		idx;
+	struct xfs_iext_cursor	icur;
 
 	/*
 	 * Search the COW fork extent list first.  This serves two purposes:
@@ -284,7 +282,7 @@ xfs_reflink_reserve_cow(
 	 * tree.
 	 */
 
-	if (!xfs_iext_lookup_extent(ip, ifp, imap->br_startoff, &idx, &got))
+	if (!xfs_iext_lookup_extent(ip, ifp, imap->br_startoff, &icur, &got))
 		eof = true;
 	if (!eof && got.br_startoff <= imap->br_startoff) {
 		trace_xfs_reflink_cow_found(ip, imap);
@@ -312,7 +310,7 @@ xfs_reflink_reserve_cow(
 		return error;
 
 	error = xfs_bmapi_reserve_delalloc(ip, XFS_COW_FORK, imap->br_startoff,
-			imap->br_blockcount, 0, &got, &idx, eof);
+			imap->br_blockcount, 0, &got, &icur, eof);
 	if (error == -ENOSPC || error == -EDQUOT)
 		trace_xfs_reflink_cow_enospc(ip, imap);
 	if (error)
@@ -353,29 +351,22 @@ xfs_reflink_convert_cow(
 	xfs_off_t		offset,
 	xfs_off_t		count)
 {
-	struct xfs_bmbt_irec	got;
-	struct xfs_defer_ops	dfops;
 	struct xfs_mount	*mp = ip->i_mount;
-	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
 	xfs_fileoff_t		offset_fsb = XFS_B_TO_FSBT(mp, offset);
 	xfs_fileoff_t		end_fsb = XFS_B_TO_FSB(mp, offset + count);
-	xfs_extnum_t		idx;
-	bool			found;
-	int			error = 0;
+	xfs_filblks_t		count_fsb = end_fsb - offset_fsb;
+	struct xfs_bmbt_irec	imap;
+	struct xfs_defer_ops	dfops;
+	xfs_fsblock_t		first_block = NULLFSBLOCK;
+	int			nimaps = 1, error = 0;
 
-	xfs_ilock(ip, XFS_ILOCK_EXCL);
+	ASSERT(count != 0);
 
-	/* Convert all the extents to real from unwritten. */
-	for (found = xfs_iext_lookup_extent(ip, ifp, offset_fsb, &idx, &got);
-	     found && got.br_startoff < end_fsb;
-	     found = xfs_iext_get_extent(ifp, ++idx, &got)) {
-		error = xfs_reflink_convert_cow_extent(ip, &got, offset_fsb,
-				end_fsb - offset_fsb, &dfops);
-		if (error)
-			break;
-	}
-
-	/* Finish up. */
+	xfs_ilock(ip, XFS_ILOCK_EXCL);
+	error = xfs_bmapi_write(NULL, ip, offset_fsb, count_fsb,
+			XFS_BMAPI_COWFORK | XFS_BMAPI_CONVERT |
+			XFS_BMAPI_CONVERT_ONLY, &first_block, 0, &imap, &nimaps,
+			&dfops);
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 	return error;
 }
@@ -399,17 +390,17 @@ xfs_reflink_allocate_cow(
 	bool			trimmed;
 	xfs_filblks_t		resaligned;
 	xfs_extlen_t		resblks = 0;
-	xfs_extnum_t		idx;
+	struct xfs_iext_cursor	icur;
 
 retry:
 	ASSERT(xfs_is_reflink_inode(ip));
-	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED));
+	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 
 	/*
 	 * 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) &&
+	if (xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &icur, &got) &&
 	    got.br_startoff <= offset_fsb) {
 		*shared = true;
 
@@ -463,6 +454,8 @@ retry:
 	if (error)
 		goto out_bmap_cancel;
 
+	xfs_inode_set_cowblocks_tag(ip);
+
 	/* Finish up. */
 	error = xfs_defer_finish(&tp, &dfops);
 	if (error)
@@ -471,6 +464,13 @@ retry:
 	error = xfs_trans_commit(tp);
 	if (error)
 		return error;
+
+	/*
+	 * Allocation succeeded but the requested range was not even partially
+	 * satisfied?  Bail out!
+	 */
+	if (nimaps == 0)
+		return -ENOSPC;
 convert:
 	return xfs_reflink_convert_cow_extent(ip, imap, offset_fsb, count_fsb,
 			&dfops);
@@ -496,13 +496,14 @@ xfs_reflink_find_cow_mapping(
 	struct xfs_ifork		*ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
 	xfs_fileoff_t			offset_fsb;
 	struct xfs_bmbt_irec		got;
-	xfs_extnum_t			idx;
+	struct xfs_iext_cursor		icur;
 
 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED));
-	ASSERT(xfs_is_reflink_inode(ip));
 
+	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, &idx, &got))
+	if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &icur, &got))
 		return false;
 	if (got.br_startoff > offset_fsb)
 		return false;
@@ -524,18 +525,18 @@ xfs_reflink_trim_irec_to_next_cow(
 {
 	struct xfs_ifork		*ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
 	struct xfs_bmbt_irec		got;
-	xfs_extnum_t			idx;
+	struct xfs_iext_cursor		icur;
 
 	if (!xfs_is_reflink_inode(ip))
 		return;
 
 	/* Find the extent in the CoW fork. */
-	if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &idx, &got))
+	if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &icur, &got))
 		return;
 
 	/* This is the extent before; try sliding up one. */
 	if (got.br_startoff < offset_fsb) {
-		if (!xfs_iext_get_extent(ifp, idx + 1, &got))
+		if (!xfs_iext_next_extent(ifp, &icur, &got))
 			return;
 	}
 
@@ -562,24 +563,32 @@ xfs_reflink_cancel_cow_blocks(
 {
 	struct xfs_ifork		*ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
 	struct xfs_bmbt_irec		got, del;
-	xfs_extnum_t			idx;
+	struct xfs_iext_cursor		icur;
 	xfs_fsblock_t			firstfsb;
 	struct xfs_defer_ops		dfops;
 	int				error = 0;
 
 	if (!xfs_is_reflink_inode(ip))
 		return 0;
-	if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &idx, &got))
+	if (!xfs_iext_lookup_extent_before(ip, ifp, &end_fsb, &icur, &got))
 		return 0;
 
-	while (got.br_startoff < end_fsb) {
+	/* Walk backwards until we're out of the I/O range... */
+	while (got.br_startoff + got.br_blockcount > offset_fsb) {
 		del = got;
 		xfs_trim_extent(&del, offset_fsb, end_fsb - offset_fsb);
+
+		/* Extent delete may have bumped ext forward */
+		if (!del.br_blockcount) {
+			xfs_iext_prev(ifp, &icur);
+			goto next_extent;
+		}
+
 		trace_xfs_reflink_cancel_cow(ip, &del);
 
 		if (isnullstartblock(del.br_startblock)) {
 			error = xfs_bmap_del_extent_delay(ip, XFS_COW_FORK,
-					&idx, &got, &del);
+					&icur, &got, &del);
 			if (error)
 				break;
 		} else if (del.br_state == XFS_EXT_UNWRITTEN || cancel_real) {
@@ -597,10 +606,6 @@ xfs_reflink_cancel_cow_blocks(
 					del.br_startblock, del.br_blockcount,
 					NULL);
 
-			/* Update quota accounting */
-			xfs_trans_mod_dquot_byino(*tpp, ip, XFS_TRANS_DQ_BCOUNT,
-					-(long)del.br_blockcount);
-
 			/* Roll the transaction */
 			xfs_defer_ijoin(&dfops, ip);
 			error = xfs_defer_finish(tpp, &dfops);
@@ -610,10 +615,20 @@ xfs_reflink_cancel_cow_blocks(
 			}
 
 			/* Remove the mapping from the CoW fork. */
-			xfs_bmap_del_extent_cow(ip, &idx, &got, &del);
-		}
+			xfs_bmap_del_extent_cow(ip, &icur, &got, &del);
 
-		if (!xfs_iext_get_extent(ifp, ++idx, &got))
+			/* Remove the quota reservation */
+			error = xfs_trans_reserve_quota_nblks(NULL, ip,
+					-(long)del.br_blockcount, 0,
+					XFS_QMOPT_RES_REGBLKS);
+			if (error)
+				break;
+		} else {
+			/* Didn't do anything, push cursor back. */
+			xfs_iext_prev(ifp, &icur);
+		}
+next_extent:
+		if (!xfs_iext_get_extent(ifp, &icur, &got))
 			break;
 	}
 
@@ -653,7 +668,7 @@ xfs_reflink_cancel_cow_range(
 
 	/* Start a rolling transaction to remove the mappings */
 	error = xfs_trans_alloc(ip->i_mount, &M_RES(ip->i_mount)->tr_write,
-			0, 0, 0, &tp);
+			0, 0, XFS_TRANS_NOFS, &tp);
 	if (error)
 		goto out;
 
@@ -698,7 +713,7 @@ xfs_reflink_end_cow(
 	int				error;
 	unsigned int			resblks;
 	xfs_filblks_t			rlen;
-	xfs_extnum_t			idx;
+	struct xfs_iext_cursor		icur;
 
 	trace_xfs_reflink_end_cow(ip, offset, count);
 
@@ -726,30 +741,29 @@ xfs_reflink_end_cow(
 			(unsigned int)(end_fsb - offset_fsb),
 			XFS_DATA_FORK);
 	error = xfs_trans_alloc(ip->i_mount, &M_RES(ip->i_mount)->tr_write,
-			resblks, 0, 0, &tp);
+			resblks, 0, XFS_TRANS_RESERVE | XFS_TRANS_NOFS, &tp);
 	if (error)
 		goto out;
 
 	xfs_ilock(ip, XFS_ILOCK_EXCL);
 	xfs_trans_ijoin(tp, ip, 0);
 
-	/* If there is a hole at end_fsb - 1 go to the previous extent */
-	if (!xfs_iext_lookup_extent(ip, ifp, end_fsb - 1, &idx, &got) ||
-	    got.br_startoff > end_fsb) {
-		ASSERT(idx > 0);
-		xfs_iext_get_extent(ifp, --idx, &got);
-	}
+	/*
+	 * In case of racing, overlapping AIO writes no COW extents might be
+	 * left by the time I/O completes for the loser of the race.  In that
+	 * case we are done.
+	 */
+	if (!xfs_iext_lookup_extent_before(ip, ifp, &end_fsb, &icur, &got))
+		goto out_cancel;
 
 	/* Walk backwards until we're out of the I/O range... */
 	while (got.br_startoff + got.br_blockcount > offset_fsb) {
 		del = got;
 		xfs_trim_extent(&del, offset_fsb, end_fsb - offset_fsb);
 
-		/* Extent delete may have bumped idx forward */
-		if (!del.br_blockcount) {
-			idx--;
-			goto next_extent;
-		}
+		/* Extent delete may have bumped ext forward */
+		if (!del.br_blockcount)
+			goto prev_extent;
 
 		ASSERT(!isnullstartblock(got.br_startblock));
 
@@ -758,10 +772,8 @@ xfs_reflink_end_cow(
 		 * speculatively preallocated CoW extents that have been
 		 * allocated but have not yet been involved in a write.
 		 */
-		if (got.br_state == XFS_EXT_UNWRITTEN) {
-			idx--;
-			goto next_extent;
-		}
+		if (got.br_state == XFS_EXT_UNWRITTEN)
+			goto prev_extent;
 
 		/* Unmap the old blocks in the data fork. */
 		xfs_defer_init(&dfops, &firstfsb);
@@ -789,15 +801,22 @@ xfs_reflink_end_cow(
 		if (error)
 			goto out_defer;
 
+		/* Charge this new data fork mapping to the on-disk quota. */
+		xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_DELBCOUNT,
+				(long)del.br_blockcount);
+
 		/* Remove the mapping from the CoW fork. */
-		xfs_bmap_del_extent_cow(ip, &idx, &got, &del);
+		xfs_bmap_del_extent_cow(ip, &icur, &got, &del);
 
 		xfs_defer_ijoin(&dfops, ip);
 		error = xfs_defer_finish(&tp, &dfops);
 		if (error)
 			goto out_defer;
-next_extent:
-		if (!xfs_iext_get_extent(ifp, idx, &got))
+		if (!xfs_iext_get_extent(ifp, &icur, &got))
+			break;
+		continue;
+prev_extent:
+		if (!xfs_iext_prev_extent(ifp, &icur, &got))
 			break;
 	}
 
@@ -809,6 +828,7 @@ next_extent:
 
 out_defer:
 	xfs_defer_cancel(&dfops);
+out_cancel:
 	xfs_trans_cancel(tp);
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 out:
@@ -937,7 +957,7 @@ xfs_reflink_set_inode_flag(
 	if (src->i_ino == dest->i_ino)
 		xfs_ilock(src, XFS_ILOCK_EXCL);
 	else
-		xfs_lock_two_inodes(src, dest, XFS_ILOCK_EXCL);
+		xfs_lock_two_inodes(src, XFS_ILOCK_EXCL, dest, XFS_ILOCK_EXCL);
 
 	if (!xfs_is_reflink_inode(src)) {
 		trace_xfs_reflink_set_inode_flag(src);
@@ -1040,7 +1060,7 @@ xfs_reflink_ag_has_free_space(
 		return 0;
 
 	pag = xfs_perag_get(mp, agno);
-	if (xfs_ag_resv_critical(pag, XFS_AG_RESV_AGFL) ||
+	if (xfs_ag_resv_critical(pag, XFS_AG_RESV_RMAPBT) ||
 	    xfs_ag_resv_critical(pag, XFS_AG_RESV_METADATA))
 		error = -ENOSPC;
 	xfs_perag_put(pag);
@@ -1195,13 +1215,16 @@ xfs_reflink_remap_blocks(
 
 	/* drange = (destoff, destoff + len); srange = (srcoff, srcoff + len) */
 	while (len) {
+		uint		lock_mode;
+
 		trace_xfs_reflink_remap_blocks_loop(src, srcoff, len,
 				dest, destoff);
+
 		/* Read extent from the source file */
 		nimaps = 1;
-		xfs_ilock(src, XFS_ILOCK_EXCL);
+		lock_mode = xfs_ilock_data_map_shared(src);
 		error = xfs_bmapi_read(src, srcoff, len, &imap, &nimaps, 0);
-		xfs_iunlock(src, XFS_ILOCK_EXCL);
+		xfs_iunlock(src, lock_mode);
 		if (error)
 			goto err;
 		ASSERT(nimaps == 1);
@@ -1238,6 +1261,50 @@ err:
 }
 
 /*
+ * Grab the exclusive iolock for a data copy from src to dest, making
+ * sure to abide vfs locking order (lowest pointer value goes first) and
+ * breaking the pnfs layout leases on dest before proceeding.  The loop
+ * is needed because we cannot call the blocking break_layout() with the
+ * src iolock held, and therefore have to back out both locks.
+ */
+static int
+xfs_iolock_two_inodes_and_break_layout(
+	struct inode		*src,
+	struct inode		*dest)
+{
+	int			error;
+
+retry:
+	if (src < dest) {
+		inode_lock_shared(src);
+		inode_lock_nested(dest, I_MUTEX_NONDIR2);
+	} else {
+		/* src >= dest */
+		inode_lock(dest);
+	}
+
+	error = break_layout(dest, false);
+	if (error == -EWOULDBLOCK) {
+		inode_unlock(dest);
+		if (src < dest)
+			inode_unlock_shared(src);
+		error = break_layout(dest, true);
+		if (error)
+			return error;
+		goto retry;
+	}
+	if (error) {
+		inode_unlock(dest);
+		if (src < dest)
+			inode_unlock_shared(src);
+		return error;
+	}
+	if (src > dest)
+		inode_lock_shared_nested(src, I_MUTEX_NONDIR2);
+	return 0;
+}
+
+/*
  * Link a range of blocks from one file to another.
  */
 int
@@ -1267,11 +1334,14 @@ xfs_reflink_remap_range(
 		return -EIO;
 
 	/* Lock both files against IO */
-	lock_two_nondirectories(inode_in, inode_out);
+	ret = xfs_iolock_two_inodes_and_break_layout(inode_in, inode_out);
+	if (ret)
+		return ret;
 	if (same_inode)
 		xfs_ilock(src, XFS_MMAPLOCK_EXCL);
 	else
-		xfs_lock_two_inodes(src, dest, XFS_MMAPLOCK_EXCL);
+		xfs_lock_two_inodes(src, XFS_MMAPLOCK_SHARED, dest,
+				XFS_MMAPLOCK_EXCL);
 
 	/* Check file eligibility and prepare for block sharing. */
 	ret = -EINVAL;
@@ -1288,8 +1358,24 @@ xfs_reflink_remap_range(
 	if (ret <= 0)
 		goto out_unlock;
 
+	/* Attach dquots to dest inode before changing block map */
+	ret = xfs_qm_dqattach(dest, 0);
+	if (ret)
+		goto out_unlock;
+
 	trace_xfs_reflink_remap_range(src, pos_in, len, dest, pos_out);
 
+	/*
+	 * Clear out post-eof preallocations because we don't have page cache
+	 * backing the delayed allocations and they'll never get freed on
+	 * their own.
+	 */
+	if (xfs_can_free_eofblocks(dest, true)) {
+		ret = xfs_free_eofblocks(dest);
+		if (ret)
+			goto out_unlock;
+	}
+
 	/* Set flags and remap blocks. */
 	ret = xfs_reflink_set_inode_flag(src, dest);
 	if (ret)
@@ -1323,10 +1409,12 @@ xfs_reflink_remap_range(
 			is_dedupe);
 
 out_unlock:
-	xfs_iunlock(src, XFS_MMAPLOCK_EXCL);
+	xfs_iunlock(dest, XFS_MMAPLOCK_EXCL);
+	if (!same_inode)
+		xfs_iunlock(src, XFS_MMAPLOCK_SHARED);
+	inode_unlock(inode_out);
 	if (!same_inode)
-		xfs_iunlock(dest, XFS_MMAPLOCK_EXCL);
-	unlock_two_nondirectories(inode_in, inode_out);
+		inode_unlock_shared(inode_in);
 	if (ret)
 		trace_xfs_reflink_remap_range_error(dest, ret, _RET_IP_);
 	return ret;
@@ -1426,7 +1514,7 @@ xfs_reflink_inode_has_shared_extents(
 	xfs_extlen_t			aglen;
 	xfs_agblock_t			rbno;
 	xfs_extlen_t			rlen;
-	xfs_extnum_t			idx;
+	struct xfs_iext_cursor		icur;
 	bool				found;
 	int				error;
 
@@ -1438,7 +1526,7 @@ xfs_reflink_inode_has_shared_extents(
 	}
 
 	*has_shared = false;
-	found = xfs_iext_lookup_extent(ip, ifp, 0, &idx, &got);
+	found = xfs_iext_lookup_extent(ip, ifp, 0, &icur, &got);
 	while (found) {
 		if (isnullstartblock(got.br_startblock) ||
 		    got.br_state != XFS_EXT_NORM)
@@ -1457,7 +1545,7 @@ xfs_reflink_inode_has_shared_extents(
 			return 0;
 		}
 next:
-		found = xfs_iext_get_extent(ifp, ++idx, &got);
+		found = xfs_iext_next_extent(ifp, &icur, &got);
 	}
 
 	return 0;