[PATCH][RESEND] pnfs/blocklayout: fix last_write_offset incorrectly set to page boundary

[Benjamin Coddington <bcodding@redhat.com>]

I'm resending this as the original was buried in a thread and I want to make
sure it gets picked up.  This fixes a bug that went in v4.8.

8<--------------------------------------------------------------------------

Commit 41963c10c47a35185e68cb9049f7a3493c94d2d7 sets the block layout's
last written byte to the offset of the end of the extent rather than the
end of the write which incorrectly updates the inode's size for
partial-page writes.

Fixes: 41963c10c47a ("pnfs/blocklayout: update last_write_offset atomically with extents")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
---
 fs/nfs/blocklayout/blocklayout.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index 217847679f0e..2905479f214a 100644
--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -344,9 +344,10 @@ static void bl_write_cleanup(struct work_struct *work)
 		u64 start = hdr->args.offset & (loff_t)PAGE_MASK;
 		u64 end = (hdr->args.offset + hdr->args.count +
 			PAGE_SIZE - 1) & (loff_t)PAGE_MASK;
+		u64 lwb = hdr->args.offset + hdr->args.count;
 
 		ext_tree_mark_written(bl, start >> SECTOR_SHIFT,
-					(end - start) >> SECTOR_SHIFT, end);
+					(end - start) >> SECTOR_SHIFT, lwb);
 	}
 
 	pnfs_ld_write_done(hdr);
-- 
2.5.5