SLUB: Fix dynamic dma kmalloc cache creation

[platform/adaptation/renesas_rcar/renesas_kernel.git] / mm / slub.c

diff --git a/mm/slub.c b/mm/slub.c
index 64fd80b..69d02e3 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -211,7 +211,8 @@ static inline void ClearSlabDebug(struct page *page)
 #define MAX_OBJECTS_PER_SLAB 65535
 
 /* Internal SLUB flags */
-#define __OBJECT_POISON 0x80000000     /* Poison object */
+#define __OBJECT_POISON                0x80000000 /* Poison object */
+#define __SYSFS_ADD_DEFERRED   0x40000000 /* Not yet visible via sysfs */
 
 /* Not all arches define cache_line_size */
 #ifndef cache_line_size
@@ -2277,10 +2278,26 @@ panic:
 }
 
 #ifdef CONFIG_ZONE_DMA
+
+static void sysfs_add_func(struct work_struct *w)
+{
+       struct kmem_cache *s;
+
+       down_write(&slub_lock);
+       list_for_each_entry(s, &slab_caches, list) {
+               if (s->flags & __SYSFS_ADD_DEFERRED) {
+                       s->flags &= ~__SYSFS_ADD_DEFERRED;
+                       sysfs_slab_add(s);
+               }
+       }
+       up_write(&slub_lock);
+}
+
+static DECLARE_WORK(sysfs_add_work, sysfs_add_func);
+
 static noinline struct kmem_cache *dma_kmalloc_cache(int index, gfp_t flags)
 {
        struct kmem_cache *s;
-       struct kmem_cache *x;
        char *text;
        size_t realsize;
 
@@ -2289,22 +2306,36 @@ static noinline struct kmem_cache *dma_kmalloc_cache(int index, gfp_t flags)
                return s;
 
        /* Dynamically create dma cache */
-       x = kmalloc(kmem_size, flags & ~SLUB_DMA);
-       if (!x)
-               panic("Unable to allocate memory for dma cache\n");
+       if (flags & __GFP_WAIT)
+               down_write(&slub_lock);
+       else {
+               if (!down_write_trylock(&slub_lock))
+                       goto out;
+       }
+
+       if (kmalloc_caches_dma[index])
+               goto unlock_out;
 
        realsize = kmalloc_caches[index].objsize;
-       text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d",
-                       (unsigned int)realsize);
-       s = create_kmalloc_cache(x, text, realsize, flags);
-       down_write(&slub_lock);
-       if (!kmalloc_caches_dma[index]) {
-               kmalloc_caches_dma[index] = s;
-               up_write(&slub_lock);
-               return s;
+       text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d", (unsigned int)realsize),
+       s = kmalloc(kmem_size, flags & ~SLUB_DMA);
+
+       if (!s || !text || !kmem_cache_open(s, flags, text,
+                       realsize, ARCH_KMALLOC_MINALIGN,
+                       SLAB_CACHE_DMA|__SYSFS_ADD_DEFERRED, NULL)) {
+               kfree(s);
+               kfree(text);
+               goto unlock_out;
        }
+
+       list_add(&s->list, &slab_caches);
+       kmalloc_caches_dma[index] = s;
+
+       schedule_work(&sysfs_add_work);
+
+unlock_out:
        up_write(&slub_lock);
-       kmem_cache_destroy(s);
+out:
        return kmalloc_caches_dma[index];
 }
 #endif