nilfs2: use set_mask_bits() for operations on buffer state bitmap

nilfs_forget_buffer(), nilfs_clear_dirty_page(), and
nilfs_segctor_complete_write() are using a bunch of atomic bit operations
against buffer state bitmap.

This reduces the number of them by utilizing set_mask_bits() macro.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 18 insertions, 20 deletions

diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c
index 700ecbcca55d..45d650addd56 100644
--- a/fs/nilfs2/page.c
+++ b/fs/nilfs2/page.c
@@ -89,18 +89,16 @@ struct buffer_head *nilfs_grab_buffer(struct inode *inode,
 void nilfs_forget_buffer(struct buffer_head *bh)
 {
         struct page *page = bh->b_page;
+        const unsigned long clear_bits =
+                (1 << BH_Uptodate | 1 << BH_Dirty | 1 << BH_Mapped |
+                 1 << BH_Async_Write | 1 << BH_NILFS_Volatile |
+                 1 << BH_NILFS_Checked | 1 << BH_NILFS_Redirected);
 
         lock_buffer(bh);
-        clear_buffer_nilfs_volatile(bh);
-        clear_buffer_nilfs_checked(bh);
-        clear_buffer_nilfs_redirected(bh);
-        clear_buffer_async_write(bh);
-        clear_buffer_dirty(bh);
+        set_mask_bits(&bh->b_state, clear_bits, 0);
         if (nilfs_page_buffers_clean(page))
                 __nilfs_clear_page_dirty(page);
 
-        clear_buffer_uptodate(bh);
-        clear_buffer_mapped(bh);
         bh->b_blocknr = -1;
         ClearPageUptodate(page);
         ClearPageMappedToDisk(page);
@@ -421,6 +419,10 @@ void nilfs_clear_dirty_page(struct page *page, bool silent)
 
         if (page_has_buffers(page)) {
                 struct buffer_head *bh, *head;
+                const unsigned long clear_bits =
+                        (1 << BH_Uptodate | 1 << BH_Dirty | 1 << BH_Mapped |
+                         1 << BH_Async_Write | 1 << BH_NILFS_Volatile |
+                         1 << BH_NILFS_Checked | 1 << BH_NILFS_Redirected);
 
                 bh = head = page_buffers(page);
                 do {
@@ -430,13 +432,7 @@ void nilfs_clear_dirty_page(struct page *page, bool silent)
                                         "discard block %llu, size %zu",
                                         (u64)bh->b_blocknr, bh->b_size);
                         }
-                        clear_buffer_async_write(bh);
-                        clear_buffer_dirty(bh);
-                        clear_buffer_nilfs_volatile(bh);
-                        clear_buffer_nilfs_checked(bh);
-                        clear_buffer_nilfs_redirected(bh);
-                        clear_buffer_uptodate(bh);
-                        clear_buffer_mapped(bh);
+                        set_mask_bits(&bh->b_state, clear_bits, 0);
                         unlock_buffer(bh);
                 } while (bh = bh->b_this_page, bh != head);
         }
diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index c9a4e6013445..c6abbad9b8e3 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -24,6 +24,7 @@
 #include <linux/pagemap.h>
 #include <linux/buffer_head.h>
 #include <linux/writeback.h>
+#include <linux/bitops.h>
 #include <linux/bio.h>
 #include <linux/completion.h>
 #include <linux/blkdev.h>
@@ -1785,12 +1786,13 @@ static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci)
                  */
                 list_for_each_entry(bh, &segbuf->sb_payload_buffers,
                                     b_assoc_buffers) {
-                        set_buffer_uptodate(bh);
-                        clear_buffer_dirty(bh);
-                        clear_buffer_async_write(bh);
-                        clear_buffer_delay(bh);
-                        clear_buffer_nilfs_volatile(bh);
-                        clear_buffer_nilfs_redirected(bh);
+                        const unsigned long set_bits = (1 << BH_Uptodate);
+                        const unsigned long clear_bits =
+                                (1 << BH_Dirty | 1 << BH_Async_Write |
+                                 1 << BH_Delay | 1 << BH_NILFS_Volatile |
+                                 1 << BH_NILFS_Redirected);
+
+                        set_mask_bits(&bh->b_state, clear_bits, set_bits);
                         if (bh == segbuf->sb_super_root) {
                                 if (bh->b_page != bd_page) {
                                         end_page_writeback(bd_page);