CacheFiles: Downgrade the requirements passed to the allocator

Downgrade the requirements passed to the allocator in the gfp flags parameter.
FS-Cache/CacheFiles can handle OOM conditions simply by aborting the attempt to
store an object or a page in the cache.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 10 insertions, 8 deletions

diff --git a/fs/cachefiles/rdwr.c b/fs/cachefiles/rdwr.c
index 3367abdcdac..9108b8ea505 100644
--- a/fs/cachefiles/rdwr.c
+++ b/fs/cachefiles/rdwr.c
@@ -238,7 +238,7 @@ static int cachefiles_read_backing_file_one(struct cachefiles_object *object,
         _debug("read back %p{%lu,%d}",
                netpage, netpage->index, page_count(netpage));
 
-        monitor = kzalloc(sizeof(*monitor), GFP_KERNEL);
+        monitor = kzalloc(sizeof(*monitor), cachefiles_gfp);
         if (!monitor)
                 goto nomem;
 
@@ -257,13 +257,14 @@ static int cachefiles_read_backing_file_one(struct cachefiles_object *object,
                         goto backing_page_already_present;
 
                 if (!newpage) {
-                        newpage = page_cache_alloc_cold(bmapping);
+                        newpage = __page_cache_alloc(cachefiles_gfp |
+                                                     __GFP_COLD);
                         if (!newpage)
                                 goto nomem_monitor;
                 }
 
                 ret = add_to_page_cache(newpage, bmapping,
-                                        netpage->index, GFP_KERNEL);
+                                        netpage->index, cachefiles_gfp);
                 if (ret == 0)
                         goto installed_new_backing_page;
                 if (ret != -EEXIST)
@@ -481,7 +482,7 @@ static int cachefiles_read_backing_file(struct cachefiles_object *object,
                        netpage, netpage->index, page_count(netpage));
 
                 if (!monitor) {
-                        monitor = kzalloc(sizeof(*monitor), GFP_KERNEL);
+                        monitor = kzalloc(sizeof(*monitor), cachefiles_gfp);
                         if (!monitor)
                                 goto nomem;
 
@@ -496,13 +497,14 @@ static int cachefiles_read_backing_file(struct cachefiles_object *object,
                                 goto backing_page_already_present;
 
                         if (!newpage) {
-                                newpage = page_cache_alloc_cold(bmapping);
+                                newpage = __page_cache_alloc(cachefiles_gfp |
+                                                             __GFP_COLD);
                                 if (!newpage)
                                         goto nomem;
                         }
 
                         ret = add_to_page_cache(newpage, bmapping,
-                                                netpage->index, GFP_KERNEL);
+                                                netpage->index, cachefiles_gfp);
                         if (ret == 0)
                                 goto installed_new_backing_page;
                         if (ret != -EEXIST)
@@ -532,7 +534,7 @@ static int cachefiles_read_backing_file(struct cachefiles_object *object,
                 _debug("- monitor add");
 
                 ret = add_to_page_cache(netpage, op->mapping, netpage->index,
-                                        GFP_KERNEL);
+                                        cachefiles_gfp);
                 if (ret < 0) {
                         if (ret == -EEXIST) {
                                 page_cache_release(netpage);
@@ -608,7 +610,7 @@ static int cachefiles_read_backing_file(struct cachefiles_object *object,
                 _debug("- uptodate");
 
                 ret = add_to_page_cache(netpage, op->mapping, netpage->index,
-                                        GFP_KERNEL);
+                                        cachefiles_gfp);
                 if (ret < 0) {
                         if (ret == -EEXIST) {
                                 page_cache_release(netpage);