bcachefs: Use memalloc_nofs_save()

vmalloc allocations don't always obey GFP_NOFS - memalloc_nofs_save() is
the prefered approach for the future.

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

diff --git a/fs/bcachefs/btree_io.c b/fs/bcachefs/btree_io.c
index e43d1b2ce5c7ad9d2770d2204a6e0d3e858452ed..85a17225a68e9ea5a0b95f0c085a45c01d88aaa8 100644 (file)
--- a/fs/bcachefs/btree_io.c
+++ b/fs/bcachefs/btree_io.c
@@ -20,6 +20,8 @@
 #include "super-io.h"
 #include "trace.h"
 
+#include <linux/sched/mm.h>
+
 static void verify_no_dups(struct btree *b,
                           struct bkey_packed *start,
                           struct bkey_packed *end,
@@ -67,17 +69,19 @@ static void btree_bounce_free(struct bch_fs *c, unsigned order,
 static void *btree_bounce_alloc(struct bch_fs *c, unsigned order,
                                bool *used_mempool)
 {
+       unsigned flags = memalloc_nofs_save();
        void *p;
 
        BUG_ON(order > btree_page_order(c));
 
        *used_mempool = false;
        p = (void *) __get_free_pages(__GFP_NOWARN|GFP_NOWAIT, order);
-       if (p)
-               return p;
-
-       *used_mempool = true;
-       return mempool_alloc(&c->btree_bounce_pool, GFP_NOIO);
+       if (!p) {
+               *used_mempool = true;
+               p = mempool_alloc(&c->btree_bounce_pool, GFP_NOIO);
+       }
+       memalloc_nofs_restore(flags);
+       return p;
 }
 
 static void sort_bkey_ptrs(const struct btree *bt,