fuse: Remove fuse_writepage

The writepage operation is deprecated as it leads to worse performance
under high memory pressure due to folios being written out in LRU order
rather than sequentially within a file.  Use filemap_migrate_folio() to
support dirty folio migration instead of writepage.

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 3ce158f70927876b462da684d4a933efa7c3393e..e42aa6b0efb2c01552438f57a5226452e68cbd78 100644 (file)
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -2104,34 +2104,6 @@ err:
        return error;
 }
 
-static int fuse_writepage(struct page *page, struct writeback_control *wbc)
-{
-       struct fuse_conn *fc = get_fuse_conn(page->mapping->host);
-       int err;
-
-       if (fuse_page_is_writeback(page->mapping->host, page->index)) {
-               /*
-                * ->writepages() should be called for sync() and friends.  We
-                * should only get here on direct reclaim and then we are
-                * allowed to skip a page which is already in flight
-                */
-               WARN_ON(wbc->sync_mode == WB_SYNC_ALL);
-
-               redirty_page_for_writepage(wbc, page);
-               unlock_page(page);
-               return 0;
-       }
-
-       if (wbc->sync_mode == WB_SYNC_NONE &&
-           fc->num_background >= fc->congestion_threshold)
-               return AOP_WRITEPAGE_ACTIVATE;
-
-       err = fuse_writepage_locked(page);
-       unlock_page(page);
-
-       return err;
-}
-
 struct fuse_fill_wb_data {
        struct fuse_writepage_args *wpa;
        struct fuse_file *ff;
@@ -3347,10 +3319,10 @@ static const struct file_operations fuse_file_operations = {
 static const struct address_space_operations fuse_file_aops  = {
        .read_folio     = fuse_read_folio,
        .readahead      = fuse_readahead,
-       .writepage      = fuse_writepage,
        .writepages     = fuse_writepages,
        .launder_folio  = fuse_launder_folio,
        .dirty_folio    = filemap_dirty_folio,
+       .migrate_folio  = filemap_migrate_folio,
        .bmap           = fuse_bmap,
        .direct_IO      = fuse_direct_IO,
        .write_begin    = fuse_write_begin,