5 files changed, 15 insertions, 13 deletions

diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index c9a24444ec9a..2256e9cceec5 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -279,7 +279,7 @@ static inline void btrfs_inode_block_unlocked_dio(struct inode *inode)
 
 static inline void btrfs_inode_resume_unlocked_dio(struct inode *inode)
 {
-        smp_mb__before_clear_bit();
+        smp_mb__before_atomic();
         clear_bit(BTRFS_INODE_READDIO_NEED_LOCK,
                   &BTRFS_I(inode)->runtime_flags);
 }
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 3955e475ceec..4cd0ac983f91 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3458,7 +3458,7 @@ static int lock_extent_buffer_for_io(struct extent_buffer *eb,
 static void end_extent_buffer_writeback(struct extent_buffer *eb)
 {
         clear_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags);
-        smp_mb__after_clear_bit();
+        smp_mb__after_atomic();
         wake_up_bit(&eb->bflags, EXTENT_BUFFER_WRITEBACK);
 }
 
@@ -4510,7 +4510,8 @@ static void check_buffer_tree_ref(struct extent_buffer *eb)
         spin_unlock(&eb->refs_lock);
 }
 
-static void mark_extent_buffer_accessed(struct extent_buffer *eb)
+static void mark_extent_buffer_accessed(struct extent_buffer *eb,
+                struct page *accessed)
 {
         unsigned long num_pages, i;
 
@@ -4519,7 +4520,8 @@ static void mark_extent_buffer_accessed(struct extent_buffer *eb)
         num_pages = num_extent_pages(eb->start, eb->len);
         for (i = 0; i < num_pages; i++) {
                 struct page *p = extent_buffer_page(eb, i);
-                mark_page_accessed(p);
+                if (p != accessed)
+                        mark_page_accessed(p);
         }
 }
 
@@ -4533,7 +4535,7 @@ struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
                                start >> PAGE_CACHE_SHIFT);
         if (eb && atomic_inc_not_zero(&eb->refs)) {
                 rcu_read_unlock();
-                mark_extent_buffer_accessed(eb);
+                mark_extent_buffer_accessed(eb, NULL);
                 return eb;
         }
         rcu_read_unlock();
@@ -4581,7 +4583,7 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
                                 spin_unlock(&mapping->private_lock);
                                 unlock_page(p);
                                 page_cache_release(p);
-                                mark_extent_buffer_accessed(exists);
+                                mark_extent_buffer_accessed(exists, p);
                                 goto free_eb;
                         }
 
@@ -4596,7 +4598,6 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
                 attach_extent_buffer_page(eb, p);
                 spin_unlock(&mapping->private_lock);
                 WARN_ON(PageDirty(p));
-                mark_page_accessed(p);
                 eb->pages[i] = p;
                 if (!PageUptodate(p))
                         uptodate = 0;
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index ae6af072b635..74272a3f9d9b 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -470,11 +470,12 @@ static void btrfs_drop_pages(struct page **pages, size_t num_pages)
         for (i = 0; i < num_pages; i++) {
                 /* page checked is some magic around finding pages that
                  * have been modified without going through btrfs_set_page_dirty
-                 * clear it here
+                 * clear it here. There should be no need to mark the pages
+                 * accessed as prepare_pages should have marked them accessed
+                 * in prepare_pages via find_or_create_page()
                  */
                 ClearPageChecked(pages[i]);
                 unlock_page(pages[i]);
-                mark_page_accessed(pages[i]);
                 page_cache_release(pages[i]);
         }
 }
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 5f805bc944fa..5a3b8371772e 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7126,7 +7126,7 @@ static void btrfs_end_dio_bio(struct bio *bio, int err)
                  * before atomic variable goto zero, we must make sure
                  * dip->errors is perceived to be set.
                  */
-                smp_mb__before_atomic_dec();
+                smp_mb__before_atomic();
         }
 
         /* if there are more bios still pending for this dio, just exit */
@@ -7306,7 +7306,7 @@ out_err:
          * before atomic variable goto zero, we must
          * make sure dip->errors is perceived to be set.
          */
-        smp_mb__before_atomic_dec();
+        smp_mb__before_atomic();
         if (atomic_dec_and_test(&dip->pending_bios))
                 bio_io_error(dip->orig_bio);
 
@@ -7449,7 +7449,7 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
                 return 0;
 
         atomic_inc(&inode->i_dio_count);
-        smp_mb__after_atomic_inc();
+        smp_mb__after_atomic();
 
         /*
          * The generic stuff only does filemap_write_and_wait_range, which
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 2f6d7b13b5bd..3f52bb7a58d2 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -642,7 +642,7 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir,
                 return -EINVAL;
 
         atomic_inc(&root->will_be_snapshoted);
-        smp_mb__after_atomic_inc();
+        smp_mb__after_atomic();
         btrfs_wait_nocow_write(root);
 
         ret = btrfs_start_delalloc_inodes(root, 0);