Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull VFS updates from Al Viro,

Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).

7kloc removed.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
  don't bother with deferred freeing of fdtables
  proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
  proc: Make the PROC_I() and PDE() macros internal to procfs
  proc: Supply a function to remove a proc entry by PDE
  take cgroup_open() and cpuset_open() to fs/proc/base.c
  ppc: Clean up scanlog
  ppc: Clean up rtas_flash driver somewhat
  hostap: proc: Use remove_proc_subtree()
  drm: proc: Use remove_proc_subtree()
  drm: proc: Use minor->index to label things, not PDE->name
  drm: Constify drm_proc_list[]
  zoran: Don't print proc_dir_entry data in debug
  reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
  proc: Supply an accessor for getting the data from a PDE's parent
  airo: Use remove_proc_subtree()
  rtl8192u: Don't need to save device proc dir PDE
  rtl8187se: Use a dir under /proc/net/r8180/
  proc: Add proc_mkdir_data()
  proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
  proc: Move PDE_NET() to fs/proc/proc_net.c
  ...

1 files changed, 40 insertions, 5 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 72043d6c88c..b12fd861260 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -27,10 +27,30 @@
 #include <linux/pfn.h>
 #include <linux/kmemleak.h>
 #include <linux/atomic.h>
+#include <linux/llist.h>
 #include <asm/uaccess.h>
 #include <asm/tlbflush.h>
 #include <asm/shmparam.h>
 
+struct vfree_deferred {
+	struct llist_head list;
+	struct work_struct wq;
+};
+static DEFINE_PER_CPU(struct vfree_deferred, vfree_deferred);
+
+static void __vunmap(const void *, int);
+
+static void free_work(struct work_struct *w)
+{
+	struct vfree_deferred *p = container_of(w, struct vfree_deferred, wq);
+	struct llist_node *llnode = llist_del_all(&p->list);
+	while (llnode) {
+		void *p = llnode;
+		llnode = llist_next(llnode);
+		__vunmap(p, 1);
+	}
+}
+
 /*** Page table manipulation functions ***/
 
 static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end)
@@ -1175,10 +1195,14 @@ void __init vmalloc_init(void)
 
 	for_each_possible_cpu(i) {
 		struct vmap_block_queue *vbq;
+		struct vfree_deferred *p;
 
 		vbq = &per_cpu(vmap_block_queue, i);
 		spin_lock_init(&vbq->lock);
 		INIT_LIST_HEAD(&vbq->free);
+		p = &per_cpu(vfree_deferred, i);
+		init_llist_head(&p->list);
+		INIT_WORK(&p->wq, free_work);
 	}
 
 	/* Import existing vmlist entries. */
@@ -1486,7 +1510,7 @@ static void __vunmap(const void *addr, int deallocate_pages)
 	kfree(area);
 	return;
 }
-
+ 
 /**
  *	vfree  -  release memory allocated by vmalloc()
  *	@addr:		memory base address
@@ -1495,15 +1519,25 @@ static void __vunmap(const void *addr, int deallocate_pages)
  *	obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is
  *	NULL, no operation is performed.
  *
- *	Must not be called in interrupt context.
+ *	Must not be called in NMI context (strictly speaking, only if we don't
+ *	have CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG, but making the calling
+ *	conventions for vfree() arch-depenedent would be a really bad idea)
+ *	
  */
 void vfree(const void *addr)
 {
-	BUG_ON(in_interrupt());
+	BUG_ON(in_nmi());
 
 	kmemleak_free(addr);
 
-	__vunmap(addr, 1);
+	if (!addr)
+		return;
+	if (unlikely(in_interrupt())) {
+		struct vfree_deferred *p = &__get_cpu_var(vfree_deferred);
+		llist_add((struct llist_node *)addr, &p->list);
+		schedule_work(&p->wq);
+	} else
+		__vunmap(addr, 1);
 }
 EXPORT_SYMBOL(vfree);
 
@@ -1520,7 +1554,8 @@ void vunmap(const void *addr)
 {
 	BUG_ON(in_interrupt());
 	might_sleep();
-	__vunmap(addr, 0);
+	if (addr)
+		__vunmap(addr, 0);
 }
 EXPORT_SYMBOL(vunmap);