[RFC PATCH 3/9] btrfs: use set/clear_fs_page_private

[Guoqing Jiang]

Since the new pair function is introduced, we can call them to clean the
code in btrfs.

Cc: Chris Mason <clm@xxxxxx>
Cc: Josef Bacik <josef@xxxxxxxxxxxxxx>
Cc: David Sterba <dsterba@xxxxxxxx>
Cc: linux-btrfs@xxxxxxxxxxxxxxx
Signed-off-by: Guoqing Jiang <guoqing.jiang@xxxxxxxxxxxxxxx>
---
 fs/btrfs/disk-io.c   |  4 +---
 fs/btrfs/extent_io.c | 21 ++++++---------------
 fs/btrfs/inode.c     | 17 ++++-------------
 3 files changed, 11 insertions(+), 31 deletions(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index a6cb5cbbdb9f..1230863e80f9 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -980,9 +980,7 @@ static void btree_invalidatepage(struct page *page, unsigned int offset,
 		btrfs_warn(BTRFS_I(page->mapping->host)->root->fs_info,
 			   "page private not zero on page %llu",
 			   (unsigned long long)page_offset(page));
-		ClearPagePrivate(page);
-		set_page_private(page, 0);
-		put_page(page);
+		clear_fs_page_private(page);
 	}
 }
 
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 39e45b8a5031..de8c2d5a99db 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3076,22 +3076,16 @@ static int submit_extent_page(unsigned int opf,
 static void attach_extent_buffer_page(struct extent_buffer *eb,
 				      struct page *page)
 {
-	if (!PagePrivate(page)) {
-		SetPagePrivate(page);
-		get_page(page);
-		set_page_private(page, (unsigned long)eb);
-	} else {
+	if (!PagePrivate(page))
+		set_fs_page_private(page, eb);
+	else
 		WARN_ON(page->private != (unsigned long)eb);
-	}
 }
 
 void set_page_extent_mapped(struct page *page)
 {
-	if (!PagePrivate(page)) {
-		SetPagePrivate(page);
-		get_page(page);
-		set_page_private(page, EXTENT_PAGE_PRIVATE);
-	}
+	if (!PagePrivate(page))
+		set_fs_page_private(page, (void *)EXTENT_PAGE_PRIVATE);
 }
 
 static struct extent_map *
@@ -4929,10 +4923,7 @@ static void btrfs_release_extent_buffer_pages(struct extent_buffer *eb)
 			 * We need to make sure we haven't be attached
 			 * to a new eb.
 			 */
-			ClearPagePrivate(page);
-			set_page_private(page, 0);
-			/* One for the page private */
-			put_page(page);
+			clear_fs_page_private(page);
 		}
 
 		if (mapped)
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 320d1062068d..07871c57ba96 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8303,11 +8303,8 @@ btrfs_readpages(struct file *file, struct address_space *mapping,
 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
 {
 	int ret = try_release_extent_mapping(page, gfp_flags);
-	if (ret == 1) {
-		ClearPagePrivate(page);
-		set_page_private(page, 0);
-		put_page(page);
-	}
+	if (ret == 1)
+		clear_fs_page_private(page);
 	return ret;
 }
 
@@ -8331,11 +8328,9 @@ static int btrfs_migratepage(struct address_space *mapping,
 
 	if (page_has_private(page)) {
 		ClearPagePrivate(page);
-		get_page(newpage);
-		set_page_private(newpage, page_private(page));
+		set_fs_page_private(newpage, (void *)page_private(page));
 		set_page_private(page, 0);
 		put_page(page);
-		SetPagePrivate(newpage);
 	}
 
 	if (PagePrivate2(page)) {
@@ -8458,11 +8453,7 @@ static void btrfs_invalidatepage(struct page *page, unsigned int offset,
 	}
 
 	ClearPageChecked(page);
-	if (PagePrivate(page)) {
-		ClearPagePrivate(page);
-		set_page_private(page, 0);
-		put_page(page);
-	}
+	clear_fs_page_private(page);
 }
 
 /*
-- 
2.17.1