Patch "xfs: Move handling of missing page into one place in xfs_find_get_desired_pgoff()" has been added to the 4.9-stable tree

Patch "xfs: Move handling of missing page into one place in xfs_find_get_desired_pgoff()" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    xfs: Move handling of missing page into one place in xfs_find_get_desired_pgoff()

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     xfs-move-handling-of-missing-page-into-one-place-in-xfs_find_get_desired_pgoff.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From a54fba8f5a0dc36161cacdf2aa90f007f702ec1a Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@suse.cz>
Date: Thu, 18 May 2017 16:36:24 -0700
Subject: xfs: Move handling of missing page into one place in xfs_find_get_desired_pgoff()

From: Jan Kara <jack@suse.cz>

commit a54fba8f5a0dc36161cacdf2aa90f007f702ec1a upstream.

Currently several places in xfs_find_get_desired_pgoff() handle the case
of a missing page. Make them all handled in one place after the loop has
terminated.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/xfs/xfs_file.c |   38 ++++++++------------------------------
 1 file changed, 8 insertions(+), 30 deletions(-)

--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1139,29 +1139,8 @@ xfs_find_get_desired_pgoff(
 		want = min_t(pgoff_t, end - index, PAGEVEC_SIZE - 1) + 1;
 		nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
 					  want);
-		/*
-		 * No page mapped into given range.  If we are searching holes
-		 * and if this is the first time we got into the loop, it means
-		 * that the given offset is landed in a hole, return it.
-		 *
-		 * If we have already stepped through some block buffers to find
-		 * holes but they all contains data.  In this case, the last
-		 * offset is already updated and pointed to the end of the last
-		 * mapped page, if it does not reach the endpoint to search,
-		 * that means there should be a hole between them.
-		 */
-		if (nr_pages == 0) {
-			/* Data search found nothing */
-			if (type == DATA_OFF)
-				break;
-
-			ASSERT(type == HOLE_OFF);
-			if (lastoff == startoff || lastoff < endoff) {
-				found = true;
-				*offset = lastoff;
-			}
+		if (nr_pages == 0)
 			break;
-		}
 
 		for (i = 0; i < nr_pages; i++) {
 			struct page	*page = pvec.pages[i];
@@ -1227,21 +1206,20 @@ xfs_find_get_desired_pgoff(
 
 		/*
 		 * The number of returned pages less than our desired, search
-		 * done.  In this case, nothing was found for searching data,
-		 * but we found a hole behind the last offset.
+		 * done.
 		 */
-		if (nr_pages < want) {
-			if (type == HOLE_OFF) {
-				*offset = lastoff;
-				found = true;
-			}
+		if (nr_pages < want)
 			break;
-		}
 
 		index = pvec.pages[i - 1]->index + 1;
 		pagevec_release(&pvec);
 	} while (index <= end);
 
+	/* No page at lastoff and we are not done - we found a hole. */
+	if (type == HOLE_OFF && lastoff < endoff) {
+		*offset = lastoff;
+		found = true;
+	}
 out:
 	pagevec_release(&pvec);
 	return found;


Patches currently in stable-queue which might be from jack@suse.cz are

queue-4.9/xfs-move-handling-of-missing-page-into-one-place-in-xfs_find_get_desired_pgoff.patch