Linux-libre 4.7.1-gnupck-4.7.1-gnu

1 files changed, 51 insertions, 24 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index ae7d20b44..e11475cde 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -21,6 +21,7 @@
 #include <linux/debugobjects.h>
 #include <linux/kallsyms.h>
 #include <linux/list.h>
+#include <linux/notifier.h>
 #include <linux/rbtree.h>
 #include <linux/radix-tree.h>
 #include <linux/rcupdate.h>
@@ -274,13 +275,12 @@ EXPORT_SYMBOL(vmalloc_to_pfn);
 
 /*** Global kva allocator ***/
 
-#define VM_LAZY_FREE	0x01
-#define VM_LAZY_FREEING	0x02
 #define VM_VM_AREA	0x04
 
 static DEFINE_SPINLOCK(vmap_area_lock);
 /* Export for kexec only */
 LIST_HEAD(vmap_area_list);
+static LLIST_HEAD(vmap_purge_list);
 static struct rb_root vmap_area_root = RB_ROOT;
 
 /* The vmap cache globals are protected by vmap_area_lock */
@@ -344,6 +344,8 @@ static void __insert_vmap_area(struct vmap_area *va)
 
 static void purge_vmap_area_lazy(void);
 
+static BLOCKING_NOTIFIER_HEAD(vmap_notify_list);
+
 /*
  * Allocate a region of KVA of the specified size and alignment, within the
  * vstart and vend.
@@ -363,6 +365,8 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,
 	BUG_ON(offset_in_page(size));
 	BUG_ON(!is_power_of_2(align));
 
+	might_sleep_if(gfpflags_allow_blocking(gfp_mask));
+
 	va = kmalloc_node(sizeof(struct vmap_area),
 			gfp_mask & GFP_RECLAIM_MASK, node);
 	if (unlikely(!va))
@@ -468,6 +472,16 @@ overflow:
 		purged = 1;
 		goto retry;
 	}
+
+	if (gfpflags_allow_blocking(gfp_mask)) {
+		unsigned long freed = 0;
+		blocking_notifier_call_chain(&vmap_notify_list, 0, &freed);
+		if (freed > 0) {
+			purged = 0;
+			goto retry;
+		}
+	}
+
 	if (printk_ratelimit())
 		pr_warn("vmap allocation for size %lu failed: use vmalloc=<size> to increase size\n",
 			size);
@@ -475,6 +489,18 @@ overflow:
 	return ERR_PTR(-EBUSY);
 }
 
+int register_vmap_purge_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&vmap_notify_list, nb);
+}
+EXPORT_SYMBOL_GPL(register_vmap_purge_notifier);
+
+int unregister_vmap_purge_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&vmap_notify_list, nb);
+}
+EXPORT_SYMBOL_GPL(unregister_vmap_purge_notifier);
+
 static void __free_vmap_area(struct vmap_area *va)
 {
 	BUG_ON(RB_EMPTY_NODE(&va->rb_node));
@@ -601,7 +627,7 @@ static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
 					int sync, int force_flush)
 {
 	static DEFINE_SPINLOCK(purge_lock);
-	LIST_HEAD(valist);
+	struct llist_node *valist;
 	struct vmap_area *va;
 	struct vmap_area *n_va;
 	int nr = 0;
@@ -620,20 +646,14 @@ static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
 	if (sync)
 		purge_fragmented_blocks_allcpus();
 
-	rcu_read_lock();
-	list_for_each_entry_rcu(va, &vmap_area_list, list) {
-		if (va->flags & VM_LAZY_FREE) {
-			if (va->va_start < *start)
-				*start = va->va_start;
-			if (va->va_end > *end)
-				*end = va->va_end;
-			nr += (va->va_end - va->va_start) >> PAGE_SHIFT;
-			list_add_tail(&va->purge_list, &valist);
-			va->flags |= VM_LAZY_FREEING;
-			va->flags &= ~VM_LAZY_FREE;
-		}
+	valist = llist_del_all(&vmap_purge_list);
+	llist_for_each_entry(va, valist, purge_list) {
+		if (va->va_start < *start)
+			*start = va->va_start;
+		if (va->va_end > *end)
+			*end = va->va_end;
+		nr += (va->va_end - va->va_start) >> PAGE_SHIFT;
 	}
-	rcu_read_unlock();
 
 	if (nr)
 		atomic_sub(nr, &vmap_lazy_nr);
@@ -643,7 +663,7 @@ static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
 
 	if (nr) {
 		spin_lock(&vmap_area_lock);
-		list_for_each_entry_safe(va, n_va, &valist, purge_list)
+		llist_for_each_entry_safe(va, n_va, valist, purge_list)
 			__free_vmap_area(va);
 		spin_unlock(&vmap_area_lock);
 	}
@@ -678,9 +698,15 @@ static void purge_vmap_area_lazy(void)
  */
 static void free_vmap_area_noflush(struct vmap_area *va)
 {
-	va->flags |= VM_LAZY_FREE;
-	atomic_add((va->va_end - va->va_start) >> PAGE_SHIFT, &vmap_lazy_nr);
-	if (unlikely(atomic_read(&vmap_lazy_nr) > lazy_max_pages()))
+	int nr_lazy;
+
+	nr_lazy = atomic_add_return((va->va_end - va->va_start) >> PAGE_SHIFT,
+				    &vmap_lazy_nr);
+
+	/* After this point, we may free va at any time */
+	llist_add(&va->purge_list, &vmap_purge_list);
+
+	if (unlikely(nr_lazy > lazy_max_pages()))
 		try_purge_vmap_area_lazy();
 }
 
@@ -1079,7 +1105,7 @@ EXPORT_SYMBOL_GPL(vm_unmap_aliases);
  */
 void vm_unmap_ram(const void *mem, unsigned int count)
 {
-	unsigned long size = count << PAGE_SHIFT;
+	unsigned long size = (unsigned long)count << PAGE_SHIFT;
 	unsigned long addr = (unsigned long)mem;
 
 	BUG_ON(!addr);
@@ -1114,7 +1140,7 @@ EXPORT_SYMBOL(vm_unmap_ram);
  */
 void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t prot)
 {
-	unsigned long size = count << PAGE_SHIFT;
+	unsigned long size = (unsigned long)count << PAGE_SHIFT;
 	unsigned long addr;
 	void *mem;
 
@@ -1548,14 +1574,15 @@ void *vmap(struct page **pages, unsigned int count,
 		unsigned long flags, pgprot_t prot)
 {
 	struct vm_struct *area;
+	unsigned long size;		/* In bytes */
 
 	might_sleep();
 
 	if (count > totalram_pages)
 		return NULL;
 
-	area = get_vm_area_caller((count << PAGE_SHIFT), flags,
-					__builtin_return_address(0));
+	size = (unsigned long)count << PAGE_SHIFT;
+	area = get_vm_area_caller(size, flags, __builtin_return_address(0));
 	if (!area)
 		return NULL;