tmpfs: no need to use i_lock

[pandora-kernel.git] / mm / slub.c

diff --git a/mm/slub.c b/mm/slub.c
index c905099..ba83f3f 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -27,6 +27,7 @@
 #include <linux/memory.h>
 #include <linux/math64.h>
 #include <linux/fault-inject.h>
+#include <linux/stacktrace.h>
 
 #include <trace/events/kmem.h>
 
@@ -589,10 +590,10 @@ static void init_object(struct kmem_cache *s, void *object, u8 val)
                memset(p + s->objsize, val, s->inuse - s->objsize);
 }
 
-static u8 *check_bytes(u8 *start, unsigned int value, unsigned int bytes)
+static u8 *check_bytes8(u8 *start, u8 value, unsigned int bytes)
 {
        while (bytes) {
-               if (*start != (u8)value)
+               if (*start != value)
                        return start;
                start++;
                bytes--;
@@ -600,6 +601,38 @@ static u8 *check_bytes(u8 *start, unsigned int value, unsigned int bytes)
        return NULL;
 }
 
+static u8 *check_bytes(u8 *start, u8 value, unsigned int bytes)
+{
+       u64 value64;
+       unsigned int words, prefix;
+
+       if (bytes <= 16)
+               return check_bytes8(start, value, bytes);
+
+       value64 = value | value << 8 | value << 16 | value << 24;
+       value64 = value64 | value64 << 32;
+       prefix = 8 - ((unsigned long)start) % 8;
+
+       if (prefix) {
+               u8 *r = check_bytes8(start, value, prefix);
+               if (r)
+                       return r;
+               start += prefix;
+               bytes -= prefix;
+       }
+
+       words = bytes / 8;
+
+       while (words) {
+               if (*(u64 *)start != value64)
+                       return check_bytes8(start, value, 8);
+               start += 8;
+               words--;
+       }
+
+       return check_bytes8(start, value, bytes % 8);
+}
+
 static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
                                                void *from, void *to)
 {
@@ -2352,16 +2385,12 @@ static inline int alloc_kmem_cache_cpus(struct kmem_cache *s)
        BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE <
                        SLUB_PAGE_SHIFT * sizeof(struct kmem_cache_cpu));
 
-#ifdef CONFIG_CMPXCHG_LOCAL
        /*
-        * Must align to double word boundary for the double cmpxchg instructions
-        * to work.
+        * Must align to double word boundary for the double cmpxchg
+        * instructions to work; see __pcpu_double_call_return_bool().
         */
-       s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu), 2 * sizeof(void *));
-#else
-       /* Regular alignment is sufficient */
-       s->cpu_slab = alloc_percpu(struct kmem_cache_cpu);
-#endif
+       s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu),
+                                    2 * sizeof(void *));
 
        if (!s->cpu_slab)
                return 0;
@@ -2964,6 +2993,42 @@ size_t ksize(const void *object)
 }
 EXPORT_SYMBOL(ksize);
 
+#ifdef CONFIG_SLUB_DEBUG
+bool verify_mem_not_deleted(const void *x)
+{
+       struct page *page;
+       void *object = (void *)x;
+       unsigned long flags;
+       bool rv;
+
+       if (unlikely(ZERO_OR_NULL_PTR(x)))
+               return false;
+
+       local_irq_save(flags);
+
+       page = virt_to_head_page(x);
+       if (unlikely(!PageSlab(page))) {
+               /* maybe it was from stack? */
+               rv = true;
+               goto out_unlock;
+       }
+
+       slab_lock(page);
+       if (on_freelist(page->slab, page, object)) {
+               object_err(page->slab, page, object, "Object is on free-list");
+               rv = false;
+       } else {
+               rv = true;
+       }
+       slab_unlock(page);
+
+out_unlock:
+       local_irq_restore(flags);
+       return rv;
+}
+EXPORT_SYMBOL(verify_mem_not_deleted);
+#endif
+
 void kfree(const void *x)
 {
        struct page *page;