bcachefs: Kill GFP_NOFAIL usage in readahead path

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/fs-io-buffered.c b/fs/bcachefs/fs-io-buffered.c
index e48b364db5aeb5015e1546f3175dc3a71723d182..73c12e565af50a465260856baaa831eb2a542caa 100644 (file)
--- a/fs/bcachefs/fs-io-buffered.c
+++ b/fs/bcachefs/fs-io-buffered.c
@@ -52,23 +52,20 @@ struct readpages_iter {
 static int readpages_iter_init(struct readpages_iter *iter,
                               struct readahead_control *ractl)
 {
-       memset(iter, 0, sizeof(*iter));
+       struct folio *folio;
 
-       iter->mapping = ractl->mapping;
+       *iter = (struct readpages_iter) { ractl->mapping };
 
-       int ret = bch2_filemap_get_contig_folios_d(iter->mapping,
-                               ractl->_index << PAGE_SHIFT,
-                               (ractl->_index + ractl->_nr_pages) << PAGE_SHIFT,
-                               0, mapping_gfp_mask(iter->mapping),
-                               &iter->folios);
-       if (ret)
-               return ret;
+       while ((folio = __readahead_folio(ractl))) {
+               if (!bch2_folio_create(folio, GFP_KERNEL) ||
+                   darray_push(&iter->folios, folio)) {
+                       bch2_folio_release(folio);
+                       ractl->_nr_pages += folio_nr_pages(folio);
+                       ractl->_index -= folio_nr_pages(folio);
+                       return iter->folios.nr ? 0 : -ENOMEM;
+               }
 
-       darray_for_each(iter->folios, fi) {
-               ractl->_nr_pages -= 1U << folio_order(*fi);
-               __bch2_folio_create(*fi, __GFP_NOFAIL|GFP_KERNEL);
-               folio_put(*fi);
-               folio_put(*fi);
+               folio_put(folio);
        }
 
        return 0;
@@ -270,12 +267,12 @@ void bch2_readahead(struct readahead_control *ractl)
        struct btree_trans *trans = bch2_trans_get(c);
        struct folio *folio;
        struct readpages_iter readpages_iter;
-       int ret;
 
        bch2_inode_opts_get(&opts, c, &inode->ei_inode);
 
-       ret = readpages_iter_init(&readpages_iter, ractl);
-       BUG_ON(ret);
+       int ret = readpages_iter_init(&readpages_iter, ractl);
+       if (ret)
+               return;
 
        bch2_pagecache_add_get(inode);