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 2d3f90afe5f1..bc7405585def 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 179cbd630f69..f7c8f7a9ea6d 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 730eff1e71a3..44e20e578ba0 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;
 }