xfs: replace KM_LARGE with explicit vmalloc use

We use the KM_LARGE flag to make kmem_alloc and friends use vmalloc
if necessary.  As we only need this for a few boot/mount time
allocations just switch to explicit vmalloc calls there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>

3 files changed, 41 insertions, 42 deletions

diff --git a/fs/xfs/linux-2.6/kmem.c b/fs/xfs/linux-2.6/kmem.c
index 2d3f90afe5f..bc7405585de 100644
--- a/fs/xfs/linux-2.6/kmem.c
+++ b/fs/xfs/linux-2.6/kmem.c
@@ -16,7 +16,6 @@
  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
 #include <linux/mm.h>
-#include <linux/vmalloc.h>
 #include <linux/highmem.h>
 #include <linux/swap.h>
 #include <linux/blkdev.h>
@@ -24,8 +23,25 @@
 #include "time.h"
 #include "kmem.h"
 
-#define MAX_VMALLOCS	6
-#define MAX_SLAB_SIZE	0x20000
+/*
+ * Greedy allocation.  May fail and may return vmalloced memory.
+ *
+ * Must be freed using kmem_free_large.
+ */
+void *
+kmem_zalloc_greedy(size_t *size, size_t minsize, size_t maxsize)
+{
+	void		*ptr;
+	size_t		kmsize = maxsize;
+
+	while (!(ptr = kmem_zalloc_large(kmsize))) {
+		if ((kmsize >>= 1) <= minsize)
+			kmsize = minsize;
+	}
+	if (ptr)
+		*size = kmsize;
+	return ptr;
+}
 
 void *
 kmem_alloc(size_t size, unsigned int __nocast flags)
@@ -34,19 +50,8 @@ kmem_alloc(size_t size, unsigned int __nocast flags)
 	gfp_t	lflags = kmem_flags_convert(flags);
 	void	*ptr;
 
-#ifdef DEBUG
-	if (unlikely(!(flags & KM_LARGE) && (size > PAGE_SIZE))) {
-		printk(KERN_WARNING "Large %s attempt, size=%ld\n",
-			__func__, (long)size);
-		dump_stack();
-	}
-#endif
-
 	do {
-		if (size < MAX_SLAB_SIZE || retries > MAX_VMALLOCS)
-			ptr = kmalloc(size, lflags);
-		else
-			ptr = __vmalloc(size, lflags, PAGE_KERNEL);
+		ptr = kmalloc(size, lflags);
 		if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
 			return ptr;
 		if (!(++retries % 100))
@@ -68,27 +73,6 @@ kmem_zalloc(size_t size, unsigned int __nocast flags)
 	return ptr;
 }
 
-void *
-kmem_zalloc_greedy(size_t *size, size_t minsize, size_t maxsize,
-		   unsigned int __nocast flags)
-{
-	void		*ptr;
-	size_t		kmsize = maxsize;
-	unsigned int	kmflags = (flags & ~KM_SLEEP) | KM_NOSLEEP;
-
-	while (!(ptr = kmem_zalloc(kmsize, kmflags))) {
-		if ((kmsize <= minsize) && (flags & KM_NOSLEEP))
-			break;
-		if ((kmsize >>= 1) <= minsize) {
-			kmsize = minsize;
-			kmflags = flags;
-		}
-	}
-	if (ptr)
-		*size = kmsize;
-	return ptr;
-}
-
 void
 kmem_free(const void *ptr)
 {
diff --git a/fs/xfs/linux-2.6/kmem.h b/fs/xfs/linux-2.6/kmem.h
index 179cbd630f6..f7c8f7a9ea6 100644
--- a/fs/xfs/linux-2.6/kmem.h
+++ b/fs/xfs/linux-2.6/kmem.h
@@ -21,6 +21,7 @@
 #include <linux/slab.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
+#include <linux/vmalloc.h>
 
 /*
  * General memory allocation interfaces
@@ -30,7 +31,6 @@
 #define KM_NOSLEEP	0x0002u
 #define KM_NOFS		0x0004u
 #define KM_MAYFAIL	0x0008u
-#define KM_LARGE	0x0010u
 
 /*
  * We use a special process flag to avoid recursive callbacks into
@@ -42,7 +42,7 @@ kmem_flags_convert(unsigned int __nocast flags)
 {
 	gfp_t	lflags;
 
-	BUG_ON(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL|KM_LARGE));
+	BUG_ON(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL));
 
 	if (flags & KM_NOSLEEP) {
 		lflags = GFP_ATOMIC | __GFP_NOWARN;
@@ -56,10 +56,25 @@ kmem_flags_convert(unsigned int __nocast flags)
 
 extern void *kmem_alloc(size_t, unsigned int __nocast);
 extern void *kmem_zalloc(size_t, unsigned int __nocast);
-extern void *kmem_zalloc_greedy(size_t *, size_t, size_t, unsigned int __nocast);
 extern void *kmem_realloc(const void *, size_t, size_t, unsigned int __nocast);
 extern void  kmem_free(const void *);
 
+static inline void *kmem_zalloc_large(size_t size)
+{
+	void *ptr;
+
+	ptr = vmalloc(size);
+	if (ptr)
+		memset(ptr, 0, size);
+	return ptr;
+}
+static inline void kmem_free_large(void *ptr)
+{
+	vfree(ptr);
+}
+
+extern void *kmem_zalloc_greedy(size_t *, size_t, size_t);
+
 /*
  * Zone interfaces
  */
diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index 730eff1e71a..44e20e578ba 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -1525,8 +1525,8 @@ xfs_alloc_bufhash(
 
 	btp->bt_hashshift = external ? 3 : 8;	/* 8 or 256 buckets */
 	btp->bt_hashmask = (1 << btp->bt_hashshift) - 1;
-	btp->bt_hash = kmem_zalloc((1 << btp->bt_hashshift) *
-					sizeof(xfs_bufhash_t), KM_SLEEP | KM_LARGE);
+	btp->bt_hash = kmem_zalloc_large((1 << btp->bt_hashshift) *
+					 sizeof(xfs_bufhash_t));
 	for (i = 0; i < (1 << btp->bt_hashshift); i++) {
 		spin_lock_init(&btp->bt_hash[i].bh_lock);
 		INIT_LIST_HEAD(&btp->bt_hash[i].bh_list);
@@ -1537,7 +1537,7 @@ STATIC void
 xfs_free_bufhash(
 	xfs_buftarg_t		*btp)
 {
-	kmem_free(btp->bt_hash);
+	kmem_free_large(btp->bt_hash);
 	btp->bt_hash = NULL;
 }