Change type of kmem_used() and kmem_size() functions to uint64_t, so it

doesn't overflow in arc.c in this check:

	if (kmem_used() > (kmem_size() * 4) / 5)
		return (1);

With this bug ZFS almost doesn't cache.

Only 32bit machines are affected that have vm.kmem_size set to values >=1GB.

Reported by:	David Taylor <davidt@yadt.co.uk>

2 files changed, 6 insertions, 6 deletions

diff --git a/sys/compat/opensolaris/kern/opensolaris_kmem.c b/sys/compat/opensolaris/kern/opensolaris_kmem.c
index a73349f..e511620 100644
--- a/sys/compat/opensolaris/kern/opensolaris_kmem.c
+++ b/sys/compat/opensolaris/kern/opensolaris_kmem.c
@@ -108,18 +108,18 @@ zfs_kmem_free(void *buf, size_t size __unused)
 	free(buf, M_SOLARIS);
 }
 
-u_long
+uint64_t
 kmem_size(void)
 {
 
-	return ((u_long)vm_kmem_size);
+	return ((uint64_t)vm_kmem_size);
 }
 
-u_long
+uint64_t
 kmem_used(void)
 {
 
-	return ((u_long)kmem_map->size);
+	return ((uint64_t)kmem_map->size);
 }
 
 static int
diff --git a/sys/compat/opensolaris/sys/kmem.h b/sys/compat/opensolaris/sys/kmem.h
index b4a2e58..6e51874 100644
--- a/sys/compat/opensolaris/sys/kmem.h
+++ b/sys/compat/opensolaris/sys/kmem.h
@@ -56,8 +56,8 @@ typedef struct kmem_cache {
 
 void *zfs_kmem_alloc(size_t size, int kmflags);
 void zfs_kmem_free(void *buf, size_t size);
-u_long kmem_size(void);
-u_long kmem_used(void);
+uint64_t kmem_size(void);
+uint64_t kmem_used(void);
 kmem_cache_t *kmem_cache_create(char *name, size_t bufsize, size_t align,
     int (*constructor)(void *, void *, int), void (*destructor)(void *, void *),
     void (*reclaim)(void *) __unused, void *private, vmem_t *vmp, int cflags);