btrfs: Remove extent_io_ops::writepage_start_hook

This hook is called only from __extent_writepage_io which is already
called only from the data page writeout path. So there is no need to
make an indirect call via extent_io_ops. This patch just removes the
callback definition, exports the callback function and calls it directly
at the only call site. Also give the function a more descriptive name.
No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 3a4d19e..a10240f 100644 (file)
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3192,6 +3192,7 @@ int btrfs_prealloc_file_range_trans(struct inode *inode,
 int btrfs_run_delalloc_range(void *private_data, struct page *locked_page,
                u64 start, u64 end, int *page_started, unsigned long *nr_written,
                struct writeback_control *wbc);
+int btrfs_writepage_cow_fixup(struct page *page, u64 start, u64 end);
 extern const struct dentry_operations btrfs_dentry_operations;
 
 /* ioctl.c */

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index dbc4202..6cec272 100644 (file)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3321,20 +3321,17 @@ static noinline_for_stack int __extent_writepage_io(struct inode *inode,
        int nr = 0;
        bool compressed;
 
-       if (tree->ops && tree->ops->writepage_start_hook) {
-               ret = tree->ops->writepage_start_hook(page, start,
-                                                     page_end);
-               if (ret) {
-                       /* Fixup worker will requeue */
-                       if (ret == -EBUSY)
-                               wbc->pages_skipped++;
-                       else
-                               redirty_page_for_writepage(wbc, page);
+       ret = btrfs_writepage_cow_fixup(page, start, page_end);
+       if (ret) {
+               /* Fixup worker will requeue */
+               if (ret == -EBUSY)
+                       wbc->pages_skipped++;
+               else
+                       redirty_page_for_writepage(wbc, page);
 
-                       update_nr_written(wbc, nr_written);
-                       unlock_page(page);
-                       return 1;
-               }
+               update_nr_written(wbc, nr_written);
+               unlock_page(page);
+               return 1;
        }
 
        /*

diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index ca48187..4275a10 100644 (file)
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -106,7 +106,6 @@ struct extent_io_ops {
        /*
         * Optional hooks, called if the pointer is not NULL
         */
-       int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
        void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
                                      struct extent_state *state, int uptodate);
        void (*set_bit_hook)(void *private_data, struct extent_state *state,

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index afc8704..2fa1a25 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2152,7 +2152,7 @@ out_page:
  * to fix it up.  The async helper will wait for ordered extents, set
  * the delalloc bit and make it safe to write the page.
  */
-static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
+int btrfs_writepage_cow_fixup(struct page *page, u64 start, u64 end)
 {
        struct inode *inode = page->mapping->host;
        struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
@@ -10527,7 +10527,6 @@ static const struct extent_io_ops btrfs_extent_io_ops = {
 
        /* optional callbacks */
        .writepage_end_io_hook = btrfs_writepage_end_io_hook,
-       .writepage_start_hook = btrfs_writepage_start_hook,
        .set_bit_hook = btrfs_set_bit_hook,
        .clear_bit_hook = btrfs_clear_bit_hook,
        .merge_extent_hook = btrfs_merge_extent_hook,