xfs: xfs_bmap_punch_delalloc_range() should take a byte range

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2155605
Tested: With xfstests and bz reproducer

Conflicts:
	- We still use xfs_discard_page()

All the callers of xfs_bmap_punch_delalloc_range() jump through
hoops to convert a byte range to filesystem blocks before calling
xfs_bmap_punch_delalloc_range(). Instead, pass the byte range to
xfs_bmap_punch_delalloc_range() and have it do the conversion to
filesystem blocks internally.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
(cherry picked from commit 7348b32)
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>

Author: cmaiolino

fs/xfs/xfs_aops.c

@@ -114,9 +114,8 @@ xfs_end_ioend(
 	if (unlikely(error)) {
 		if (ioend->io_flags & IOMAP_F_SHARED) {
 			xfs_reflink_cancel_cow_range(ip, offset, size, true);
-			xfs_bmap_punch_delalloc_range(ip,
-						      XFS_B_TO_FSBT(mp, offset),
-						      XFS_B_TO_FSB(mp, size));
+			xfs_bmap_punch_delalloc_range(ip, offset,
+					offset + size);
 		}
 		goto done;
 	}
@@ -441,12 +440,9 @@ xfs_discard_page(
 	struct page		*page,
 	loff_t			fileoff)
 {
-	struct inode		*inode = page->mapping->host;
-	struct xfs_inode	*ip = XFS_I(inode);
+	struct xfs_inode	*ip = XFS_I(page->mapping->host);
 	struct xfs_mount	*mp = ip->i_mount;
 	unsigned int		pageoff = offset_in_page(fileoff);
-	xfs_fileoff_t		start_fsb = XFS_B_TO_FSBT(mp, fileoff);
-	xfs_fileoff_t		pageoff_fsb = XFS_B_TO_FSBT(mp, pageoff);
 	int			error;
 
 	if (xfs_is_shutdown(mp))
@@ -456,8 +452,8 @@ xfs_discard_page(
 		"page discard on page "PTR_FMT", inode 0x%llx, offset %llu.",
 			page, ip->i_ino, fileoff);
 
-	error = xfs_bmap_punch_delalloc_range(ip, start_fsb,
-			i_blocks_per_page(inode, page) - pageoff_fsb);
+	error = xfs_bmap_punch_delalloc_range(ip, fileoff,
+			round_up(fileoff, PAGE_SIZE));
 	if (error && !xfs_is_shutdown(mp))
 		xfs_alert(mp, "page discard unable to remove delalloc mapping.");
 out_invalidate:

fs/xfs/xfs_bmap_util.c

@@ -589,11 +589,13 @@ xfs_getbmap(
 int
 xfs_bmap_punch_delalloc_range(
 	struct xfs_inode	*ip,
-	xfs_fileoff_t		start_fsb,
-	xfs_fileoff_t		length)
+	xfs_off_t		start_byte,
+	xfs_off_t		end_byte)
 {
+	struct xfs_mount	*mp = ip->i_mount;
 	struct xfs_ifork	*ifp = &ip->i_df;
-	xfs_fileoff_t		end_fsb = start_fsb + length;
+	xfs_fileoff_t		start_fsb = XFS_B_TO_FSBT(mp, start_byte);
+	xfs_fileoff_t		end_fsb = XFS_B_TO_FSB(mp, end_byte);
 	struct xfs_bmbt_irec	got, del;
 	struct xfs_iext_cursor	icur;
 	int			error = 0;
@@ -606,7 +608,7 @@ xfs_bmap_punch_delalloc_range(
 
 	while (got.br_startoff + got.br_blockcount > start_fsb) {
 		del = got;
-		xfs_trim_extent(&del, start_fsb, length);
+		xfs_trim_extent(&del, start_fsb, end_fsb - start_fsb);
 
 		/*
 		 * A delete can push the cursor forward. Step back to the

fs/xfs/xfs_bmap_util.h

@@ -31,7 +31,7 @@ xfs_bmap_rtalloc(struct xfs_bmalloca *ap)
 #endif /* CONFIG_XFS_RT */
 
 int	xfs_bmap_punch_delalloc_range(struct xfs_inode *ip,
-		xfs_fileoff_t start_fsb, xfs_fileoff_t length);
+		xfs_off_t start_byte, xfs_off_t end_byte);
 
 struct kgetbmap {
 	__s64		bmv_offset;	/* file offset of segment in blocks */

fs/xfs/xfs_iomap.c

@@ -1081,12 +1081,8 @@ xfs_buffered_write_delalloc_punch(
 	loff_t			offset,
 	loff_t			length)
 {
-	struct xfs_mount	*mp = XFS_M(inode->i_sb);
-	xfs_fileoff_t		start_fsb = XFS_B_TO_FSBT(mp, offset);
-	xfs_fileoff_t		end_fsb = XFS_B_TO_FSB(mp, offset + length);
-
-	return xfs_bmap_punch_delalloc_range(XFS_I(inode), start_fsb,
-				end_fsb - start_fsb);
+	return xfs_bmap_punch_delalloc_range(XFS_I(inode), offset,
+			offset + length);
 }
 
 static int