[PATCH V7 06/13] Btrfs: Search for all ordered extents that could span across a page

From: Chandan Rajendra <chandan@linux.vnet.ibm.com>
To: linux-btrfs@vger.kernel.org
Cc: Chandan Rajendra <chandan@linux.vnet.ibm.com>,
	clm@fb.com, jbacik@fb.com, bo.li.liu@oracle.com, dsterba@suse.cz,
	quwenruo@cn.fujitsu.com, chandan@mykolab.com
Subject: [PATCH V7 06/13] Btrfs: Search for all ordered extents that could span across a page
Date: Tue, 27 Oct 2015 15:09:39 +0530	[thread overview]
Message-ID: <1445938786-12488-7-git-send-email-chandan@linux.vnet.ibm.com> (raw)
In-Reply-To: <1445938786-12488-1-git-send-email-chandan@linux.vnet.ibm.com>

In subpagesize-blocksize scenario it is not sufficient to search using the
first byte of the page to make sure that there are no ordered extents
present across the page. Fix this.

Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
---
 fs/btrfs/extent_io.c |  3 ++-
 fs/btrfs/inode.c     | 25 ++++++++++++++++++-------
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 33a01ea..d093643 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3281,7 +3281,8 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
 
 	while (1) {
 		lock_extent(tree, start, end);
-		ordered = btrfs_lookup_ordered_extent(inode, start);
+		ordered = btrfs_lookup_ordered_range(inode, start,
+						PAGE_CACHE_SIZE);
 		if (!ordered)
 			break;
 		unlock_extent(tree, start, end);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 8c5b33a..c883ae8 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1990,7 +1990,8 @@ again:
 	if (PagePrivate2(page))
 		goto out;
 
-	ordered = btrfs_lookup_ordered_extent(inode, page_start);
+	ordered = btrfs_lookup_ordered_range(inode, page_start,
+					PAGE_CACHE_SIZE);
 	if (ordered) {
 		unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
 				     page_end, &cached_state, GFP_NOFS);
@@ -8653,6 +8654,8 @@ static void btrfs_invalidatepage(struct page *page, unsigned int offset,
 	struct extent_state *cached_state = NULL;
 	u64 page_start = page_offset(page);
 	u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
+	u64 start;
+	u64 end;
 	int inode_evicting = inode->i_state & I_FREEING;
 
 	/*
@@ -8672,14 +8675,18 @@ static void btrfs_invalidatepage(struct page *page, unsigned int offset,
 
 	if (!inode_evicting)
 		lock_extent_bits(tree, page_start, page_end, 0, &cached_state);
-	ordered = btrfs_lookup_ordered_extent(inode, page_start);
+again:
+	start = page_start;
+	ordered = btrfs_lookup_ordered_range(inode, start,
+					page_end - start + 1);
 	if (ordered) {
+		end = min(page_end, ordered->file_offset + ordered->len - 1);
 		/*
 		 * IO on this page will never be started, so we need
 		 * to account for any ordered extents now
 		 */
 		if (!inode_evicting)
-			clear_extent_bit(tree, page_start, page_end,
+			clear_extent_bit(tree, start, end,
 					 EXTENT_DIRTY | EXTENT_DELALLOC |
 					 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
 					 EXTENT_DEFRAG, 1, 0, &cached_state,
@@ -8696,22 +8703,26 @@ static void btrfs_invalidatepage(struct page *page, unsigned int offset,
 
 			spin_lock_irq(&tree->lock);
 			set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags);
-			new_len = page_start - ordered->file_offset;
+			new_len = start - ordered->file_offset;
 			if (new_len < ordered->truncated_len)
 				ordered->truncated_len = new_len;
 			spin_unlock_irq(&tree->lock);
 
 			if (btrfs_dec_test_ordered_pending(inode, &ordered,
-							   page_start,
-							   PAGE_CACHE_SIZE, 1))
+							   start,
+							   end - start + 1, 1))
 				btrfs_finish_ordered_io(ordered);
 		}
 		btrfs_put_ordered_extent(ordered);
 		if (!inode_evicting) {
 			cached_state = NULL;
-			lock_extent_bits(tree, page_start, page_end, 0,
+			lock_extent_bits(tree, start, end, 0,
 					 &cached_state);
 		}
+
+		start = end + 1;
+		if (start < page_end)
+			goto again;
 	}
 
 	/*
-- 
2.1.0

