From: Wengang Wang <wen.gang.wang@oracle.com>
Date: Tue, 29 Jan 2019 03:19:09 +0000 (-0800)
Subject: Revert "xfs: remove xfs_cancel_ioend"
X-Git-Tag: v4.1.12-124.31.3~309
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=a60668522bb8963c65dfe1ca808c4f6a09488a64;p=users%2Fjedix%2Flinux-maple.git

Revert "xfs: remove xfs_cancel_ioend"

This reverts commit c680537035066177fa845053354974f7245c02d8.

These commits are very possibly to cause SIGBUS issue. (We can't verify
that in customer's environment). Revert them.

Orabug: 29279692

Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Reviewed-by: Shan Hai <shan.hai@oracle.com>
Signed-off-by: Brian Maly <brian.maly@oracle.com>
---

diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 0a0f5c9294f1..75edf5846f32 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -527,6 +527,38 @@ xfs_submit_ioend(
 	} while ((ioend = next) != NULL);
 }
 
+/*
+ * Cancel submission of all buffer_heads so far in this endio.
+ * Toss the endio too.  Only ever called for the initial page
+ * in a writepage request, so only ever one page.
+ */
+STATIC void
+xfs_cancel_ioend(
+	xfs_ioend_t		*ioend)
+{
+	xfs_ioend_t		*next;
+	struct buffer_head	*bh, *next_bh;
+
+	do {
+		next = ioend->io_list;
+		bh = ioend->io_buffer_head;
+		do {
+			next_bh = bh->b_private;
+			clear_buffer_async_write(bh);
+			/*
+			 * The unwritten flag is cleared when added to the
+			 * ioend. We're not submitting for I/O so mark the
+			 * buffer unwritten again for next time around.
+			 */
+			if (ioend->io_type == XFS_IO_UNWRITTEN)
+				set_buffer_unwritten(bh);
+			unlock_buffer(bh);
+		} while ((bh = next_bh) != NULL);
+
+		mempool_free(ioend, xfs_ioend_pool);
+	} while ((ioend = next) != NULL);
+}
+
 /*
  * Test to see if we've been building up a completion structure for
  * earlier buffers -- if so, we try to append to this ioend if we
@@ -899,28 +931,6 @@ out_invalidate:
 	return;
 }
 
-static int
-xfs_writepage_submit(
-	struct xfs_ioend	*ioend,
-	struct xfs_ioend	*iohead,
-	struct writeback_control *wbc,
-	int			status)
-{
-	struct blk_plug		plug;
-
-	/* Reserve log space if we might write beyond the on-disk inode size. */
-	if (!status && ioend && ioend->io_type != XFS_IO_UNWRITTEN &&
-	    xfs_ioend_is_append(ioend))
-		status = xfs_setfilesize_trans_alloc(ioend);
-
-	if (iohead) {
-		blk_start_plug(&plug);
-		xfs_submit_ioend(wbc, iohead, status);
-		blk_finish_plug(&plug);
-	}
-	return status;
-}
-
 /*
  * Write out a dirty page.
  *
@@ -1132,7 +1142,6 @@ xfs_vm_writepage(
 		return 0;
 
 	ASSERT(iohead);
-	ASSERT(err == 0);
 
 	/*
 	 * Any errors from this point onwards need tobe reported through the IO
@@ -1158,33 +1167,25 @@ xfs_vm_writepage(
 				  wbc, end_index);
 	}
 
-	return xfs_writepage_submit(ioend, iohead, wbc, 0);
 
-error:
 	/*
-	 * On error, we have to fail the iohead here because we buffers locked
-	 * in the ioend chain. If we don't do this, we'll deadlock invalidating
-	 * the page as that tries to lock the buffers on the page. Also, because
-	 * we may have set pages under writeback, we have to run IO completion to
-	 * mark the error state of the IO appropriately, so we can't cancel the
-	 * ioend directly here. That means we have to mark this page as under
-	 * writeback if we included any buffers from it in the ioend chain.
+	 * Reserve log space if we might write beyond the on-disk inode size.
 	 */
-	if (count)
-		xfs_start_page_writeback(page, 0, count);
-	xfs_writepage_submit(ioend, iohead, wbc, err);
+	err = 0;
+	if (ioend->io_type != XFS_IO_UNWRITTEN && xfs_ioend_is_append(ioend))
+		err = xfs_setfilesize_trans_alloc(ioend);
 
-	/*
-	 * We can only discard the page we had the IO error on if we haven't
-	 * included it in the ioend above. If it has already been errored out,
-	 * the it is unlocked and we can't touch it here.
-	 */
-	if (!count) {
-		xfs_aops_discard_page(page);
-		ClearPageUptodate(page);
-		unlock_page(page);
-	}
-	mapping_set_error(page->mapping, err);
+	xfs_submit_ioend(wbc, iohead, err);
+
+	return 0;
+
+error:
+	if (iohead)
+		xfs_cancel_ioend(iohead);
+
+	xfs_aops_discard_page(page);
+	ClearPageUptodate(page);
+	unlock_page(page);
 	return err;
 
 redirty: