Revert "xfs: use iomap_valid method to detect stale cached iomaps"

This reverts commit ea67e73129 which is
commit 304a68b9c6 upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: I371fe53ba28e2f032a4befb0f3e8d006d52a7167
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

fs/xfs/libxfs/xfs_bmap.c

@@ -4551,8 +4551,7 @@ xfs_bmapi_convert_delalloc(
 	 * the extent.  Just return the real extent at this offset.
 	 */
 	if (!isnullstartblock(bma.got.br_startblock)) {
-		xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags,
-				xfs_iomap_inode_sequence(ip, flags));
+		xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags);
 		*seq = READ_ONCE(ifp->if_seq);
 		goto out_trans_cancel;
 	}
@@ -4600,8 +4599,7 @@ xfs_bmapi_convert_delalloc(
 	XFS_STATS_INC(mp, xs_xstrat_quick);
 
 	ASSERT(!isnullstartblock(bma.got.br_startblock));
-	xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags,
-				xfs_iomap_inode_sequence(ip, flags));
+	xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags);
 	*seq = READ_ONCE(ifp->if_seq);
 
 	if (whichfork == XFS_COW_FORK)

fs/xfs/xfs_aops.c

@@ -372,7 +372,7 @@ retry:
 	    isnullstartblock(imap.br_startblock))
 		goto allocate_blocks;
 
-	xfs_bmbt_to_iomap(ip, &wpc->iomap, &imap, 0, 0, XFS_WPC(wpc)->data_seq);
+	xfs_bmbt_to_iomap(ip, &wpc->iomap, &imap, 0, 0);
 	trace_xfs_map_blocks_found(ip, offset, count, whichfork, &imap);
 	return 0;
 allocate_blocks:

fs/xfs/xfs_iomap.c

@@ -48,45 +48,13 @@ xfs_alert_fsblock_zero(
 	return -EFSCORRUPTED;
 }
 
-u64
-xfs_iomap_inode_sequence(
-	struct xfs_inode	*ip,
-	u16			iomap_flags)
-{
-	u64			cookie = 0;
-
-	if (iomap_flags & IOMAP_F_XATTR)
-		return READ_ONCE(ip->i_af.if_seq);
-	if ((iomap_flags & IOMAP_F_SHARED) && ip->i_cowfp)
-		cookie = (u64)READ_ONCE(ip->i_cowfp->if_seq) << 32;
-	return cookie | READ_ONCE(ip->i_df.if_seq);
-}
-
-/*
- * Check that the iomap passed to us is still valid for the given offset and
- * length.
- */
-static bool
-xfs_iomap_valid(
-	struct inode		*inode,
-	const struct iomap	*iomap)
-{
-	return iomap->validity_cookie ==
-			xfs_iomap_inode_sequence(XFS_I(inode), iomap->flags);
-}
-
-const struct iomap_page_ops xfs_iomap_page_ops = {
-	.iomap_valid		= xfs_iomap_valid,
-};
-
 int
 xfs_bmbt_to_iomap(
 	struct xfs_inode	*ip,
 	struct iomap		*iomap,
 	struct xfs_bmbt_irec	*imap,
 	unsigned int		mapping_flags,
-	u16			iomap_flags,
-	u64			sequence_cookie)
+	u16			iomap_flags)
 {
 	struct xfs_mount	*mp = ip->i_mount;
 	struct xfs_buftarg	*target = xfs_inode_buftarg(ip);
@@ -123,9 +91,6 @@ xfs_bmbt_to_iomap(
 	if (xfs_ipincount(ip) &&
 	    (ip->i_itemp->ili_fsync_fields & ~XFS_ILOG_TIMESTAMP))
 		iomap->flags |= IOMAP_F_DIRTY;
-
-	iomap->validity_cookie = sequence_cookie;
-	iomap->page_ops = &xfs_iomap_page_ops;
 	return 0;
 }
 
@@ -230,8 +195,7 @@ xfs_iomap_write_direct(
 	xfs_fileoff_t		offset_fsb,
 	xfs_fileoff_t		count_fsb,
 	unsigned int		flags,
-	struct xfs_bmbt_irec	*imap,
-	u64			*seq)
+	struct xfs_bmbt_irec	*imap)
 {
 	struct xfs_mount	*mp = ip->i_mount;
 	struct xfs_trans	*tp;
@@ -321,7 +285,6 @@ xfs_iomap_write_direct(
 		error = xfs_alert_fsblock_zero(ip, imap);
 
 out_unlock:
-	*seq = xfs_iomap_inode_sequence(ip, 0);
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 	return error;
 
@@ -780,7 +743,6 @@ xfs_direct_write_iomap_begin(
 	bool			shared = false;
 	u16			iomap_flags = 0;
 	unsigned int		lockmode = XFS_ILOCK_SHARED;
-	u64			seq;
 
 	ASSERT(flags & (IOMAP_WRITE | IOMAP_ZERO));
 
@@ -849,10 +811,9 @@ xfs_direct_write_iomap_begin(
 			goto out_unlock;
 	}
 
-	seq = xfs_iomap_inode_sequence(ip, iomap_flags);
 	xfs_iunlock(ip, lockmode);
 	trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap);
-	return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, iomap_flags, seq);
+	return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, iomap_flags);
 
 allocate_blocks:
 	error = -EAGAIN;
@@ -878,26 +839,24 @@ allocate_blocks:
 	xfs_iunlock(ip, lockmode);
 
 	error = xfs_iomap_write_direct(ip, offset_fsb, end_fsb - offset_fsb,
-			flags, &imap, &seq);
+			flags, &imap);
 	if (error)
 		return error;
 
 	trace_xfs_iomap_alloc(ip, offset, length, XFS_DATA_FORK, &imap);
 	return xfs_bmbt_to_iomap(ip, iomap, &imap, flags,
-				 iomap_flags | IOMAP_F_NEW, seq);
+				 iomap_flags | IOMAP_F_NEW);
 
 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) {
-		seq = xfs_iomap_inode_sequence(ip, 0);
-		error = xfs_bmbt_to_iomap(ip, srcmap, &imap, flags, 0, seq);
+		error = xfs_bmbt_to_iomap(ip, srcmap, &imap, flags, 0);
 		if (error)
-			goto out_unlock;
+			return error;
 	}
-	seq = xfs_iomap_inode_sequence(ip, IOMAP_F_SHARED);
-	xfs_iunlock(ip, lockmode);
-	return xfs_bmbt_to_iomap(ip, iomap, &cmap, flags, IOMAP_F_SHARED, seq);
+	return xfs_bmbt_to_iomap(ip, iomap, &cmap, flags, IOMAP_F_SHARED);
 
 out_unlock:
 	if (lockmode)
@@ -956,7 +915,6 @@ xfs_buffered_write_iomap_begin(
 	int			allocfork = XFS_DATA_FORK;
 	int			error = 0;
 	unsigned int		lockmode = XFS_ILOCK_EXCL;
-	u64			seq;
 
 	if (xfs_is_shutdown(mp))
 		return -EIO;
@@ -1136,31 +1094,26 @@ retry:
 	 * Flag newly allocated delalloc blocks with IOMAP_F_NEW so we punch
 	 * them out if the write happens to fail.
 	 */
-	seq = xfs_iomap_inode_sequence(ip, IOMAP_F_NEW);
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 	trace_xfs_iomap_alloc(ip, offset, count, allocfork, &imap);
-	return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, IOMAP_F_NEW, seq);
+	return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, IOMAP_F_NEW);
 
 found_imap:
-	seq = xfs_iomap_inode_sequence(ip, 0);
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
-	return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, 0, seq);
+	return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, 0);
 
 found_cow:
-	seq = xfs_iomap_inode_sequence(ip, 0);
+	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 	if (imap.br_startoff <= offset_fsb) {
-		error = xfs_bmbt_to_iomap(ip, srcmap, &imap, flags, 0, seq);
+		error = xfs_bmbt_to_iomap(ip, srcmap, &imap, flags, 0);
 		if (error)
-			goto out_unlock;
-		seq = xfs_iomap_inode_sequence(ip, IOMAP_F_SHARED);
-		xfs_iunlock(ip, XFS_ILOCK_EXCL);
+			return error;
 		return xfs_bmbt_to_iomap(ip, iomap, &cmap, flags,
-					 IOMAP_F_SHARED, seq);
+					 IOMAP_F_SHARED);
 	}
 
 	xfs_trim_extent(&cmap, offset_fsb, imap.br_startoff - offset_fsb);
-	xfs_iunlock(ip, XFS_ILOCK_EXCL);
-	return xfs_bmbt_to_iomap(ip, iomap, &cmap, flags, 0, seq);
+	return xfs_bmbt_to_iomap(ip, iomap, &cmap, flags, 0);
 
 out_unlock:
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
@@ -1231,7 +1184,6 @@ xfs_read_iomap_begin(
 	int			nimaps = 1, error = 0;
 	bool			shared = false;
 	unsigned int		lockmode = XFS_ILOCK_SHARED;
-	u64			seq;
 
 	ASSERT(!(flags & (IOMAP_WRITE | IOMAP_ZERO)));
 
@@ -1245,14 +1197,13 @@ xfs_read_iomap_begin(
 			       &nimaps, 0);
 	if (!error && (flags & IOMAP_REPORT))
 		error = xfs_reflink_trim_around_shared(ip, &imap, &shared);
-	seq = xfs_iomap_inode_sequence(ip, shared ? IOMAP_F_SHARED : 0);
 	xfs_iunlock(ip, lockmode);
 
 	if (error)
 		return error;
 	trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap);
 	return xfs_bmbt_to_iomap(ip, iomap, &imap, flags,
-				 shared ? IOMAP_F_SHARED : 0, seq);
+				 shared ? IOMAP_F_SHARED : 0);
 }
 
 const struct iomap_ops xfs_read_iomap_ops = {
@@ -1277,7 +1228,6 @@ xfs_seek_iomap_begin(
 	struct xfs_bmbt_irec	imap, cmap;
 	int			error = 0;
 	unsigned		lockmode;
-	u64			seq;
 
 	if (xfs_is_shutdown(mp))
 		return -EIO;
@@ -1312,9 +1262,8 @@ xfs_seek_iomap_begin(
 		if (data_fsb < cow_fsb + cmap.br_blockcount)
 			end_fsb = min(end_fsb, data_fsb);
 		xfs_trim_extent(&cmap, offset_fsb, end_fsb);
-		seq = xfs_iomap_inode_sequence(ip, IOMAP_F_SHARED);
 		error = xfs_bmbt_to_iomap(ip, iomap, &cmap, flags,
-				IOMAP_F_SHARED, seq);
+					  IOMAP_F_SHARED);
 		/*
 		 * This is a COW extent, so we must probe the page cache
 		 * because there could be dirty page cache being backed
@@ -1335,9 +1284,8 @@ xfs_seek_iomap_begin(
 	imap.br_startblock = HOLESTARTBLOCK;
 	imap.br_state = XFS_EXT_NORM;
 done:
-	seq = xfs_iomap_inode_sequence(ip, 0);
 	xfs_trim_extent(&imap, offset_fsb, end_fsb);
-	error = xfs_bmbt_to_iomap(ip, iomap, &imap, flags, 0, seq);
+	error = xfs_bmbt_to_iomap(ip, iomap, &imap, flags, 0);
 out_unlock:
 	xfs_iunlock(ip, lockmode);
 	return error;
@@ -1363,7 +1311,6 @@ xfs_xattr_iomap_begin(
 	struct xfs_bmbt_irec	imap;
 	int			nimaps = 1, error = 0;
 	unsigned		lockmode;
-	int			seq;
 
 	if (xfs_is_shutdown(mp))
 		return -EIO;
@@ -1380,14 +1327,12 @@ xfs_xattr_iomap_begin(
 	error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap,
 			       &nimaps, XFS_BMAPI_ATTRFORK);
 out_unlock:
-
-	seq = xfs_iomap_inode_sequence(ip, IOMAP_F_XATTR);
 	xfs_iunlock(ip, lockmode);
 
 	if (error)
 		return error;
 	ASSERT(nimaps);
-	return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, IOMAP_F_XATTR, seq);
+	return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, 0);
 }
 
 const struct iomap_ops xfs_xattr_iomap_ops = {

fs/xfs/xfs_iomap.h

@@ -13,15 +13,14 @@ struct xfs_bmbt_irec;
 
 int xfs_iomap_write_direct(struct xfs_inode *ip, xfs_fileoff_t offset_fsb,
 		xfs_fileoff_t count_fsb, unsigned int flags,
-		struct xfs_bmbt_irec *imap, u64 *sequence);
+		struct xfs_bmbt_irec *imap);
 int xfs_iomap_write_unwritten(struct xfs_inode *, xfs_off_t, xfs_off_t, bool);
 xfs_fileoff_t xfs_iomap_eof_align_last_fsb(struct xfs_inode *ip,
 		xfs_fileoff_t end_fsb);
 
-u64 xfs_iomap_inode_sequence(struct xfs_inode *ip, u16 iomap_flags);
 int xfs_bmbt_to_iomap(struct xfs_inode *ip, struct iomap *iomap,
 		struct xfs_bmbt_irec *imap, unsigned int mapping_flags,
-		u16 iomap_flags, u64 sequence_cookie);
+		u16 iomap_flags);
 
 int xfs_zero_range(struct xfs_inode *ip, loff_t pos, loff_t len,
 		bool *did_zero);

fs/xfs/xfs_pnfs.c

@@ -125,7 +125,6 @@ xfs_fs_map_blocks(
 	int			nimaps = 1;
 	uint			lock_flags;
 	int			error = 0;
-	u64			seq;
 
 	if (xfs_is_shutdown(mp))
 		return -EIO;
@@ -177,7 +176,6 @@ xfs_fs_map_blocks(
 	lock_flags = xfs_ilock_data_map_shared(ip);
 	error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb,
 				&imap, &nimaps, bmapi_flags);
-	seq = xfs_iomap_inode_sequence(ip, 0);
 
 	ASSERT(!nimaps || imap.br_startblock != DELAYSTARTBLOCK);
 
@@ -191,7 +189,7 @@ xfs_fs_map_blocks(
 		xfs_iunlock(ip, lock_flags);
 
 		error = xfs_iomap_write_direct(ip, offset_fsb,
-				end_fsb - offset_fsb, 0, &imap, &seq);
+				end_fsb - offset_fsb, 0, &imap);
 		if (error)
 			goto out_unlock;
 
@@ -211,7 +209,7 @@ xfs_fs_map_blocks(
 	}
 	xfs_iunlock(ip, XFS_IOLOCK_EXCL);
 
-	error = xfs_bmbt_to_iomap(ip, iomap, &imap, 0, 0, seq);
+	error = xfs_bmbt_to_iomap(ip, iomap, &imap, 0, 0);
 	*device_generation = mp->m_generation;
 	return error;
 out_unlock: