mm: move kvmalloc-related functions to slab.h

Not all files in the kernel should include mm.h.  Migrating callers from
kmalloc to kvmalloc is easier if the kvmalloc functions are in slab.h.

[akpm@linux-foundation.org: move the new kvrealloc() also]
[akpm@linux-foundation.org: drivers/hwmon/occ/p9_sbe.c needs slab.h]

Link: https://lkml.kernel.org/r/20210622215757.3525604-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/hwmon/occ/p9_sbe.c

@@ -3,6 +3,7 @@
 
 #include <linux/device.h>
 #include <linux/errno.h>
+#include <linux/slab.h>
 #include <linux/fsi-occ.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>

drivers/of/kexec.c

@@ -16,6 +16,7 @@
 #include <linux/of.h>
 #include <linux/of_fdt.h>
 #include <linux/random.h>
+#include <linux/slab.h>
 #include <linux/types.h>
 
 #define RNG_SEED_SIZE		128

include/linux/mm.h

@@ -799,40 +799,6 @@ static inline int is_vmalloc_or_module_addr(const void *x)
 }
 #endif
 
-extern void *kvmalloc_node(size_t size, gfp_t flags, int node);
-static inline void *kvmalloc(size_t size, gfp_t flags)
-{
-	return kvmalloc_node(size, flags, NUMA_NO_NODE);
-}
-static inline void *kvzalloc_node(size_t size, gfp_t flags, int node)
-{
-	return kvmalloc_node(size, flags | __GFP_ZERO, node);
-}
-static inline void *kvzalloc(size_t size, gfp_t flags)
-{
-	return kvmalloc(size, flags | __GFP_ZERO);
-}
-
-static inline void *kvmalloc_array(size_t n, size_t size, gfp_t flags)
-{
-	size_t bytes;
-
-	if (unlikely(check_mul_overflow(n, size, &bytes)))
-		return NULL;
-
-	return kvmalloc(bytes, flags);
-}
-
-static inline void *kvcalloc(size_t n, size_t size, gfp_t flags)
-{
-	return kvmalloc_array(n, size, flags | __GFP_ZERO);
-}
-
-extern void *kvrealloc(const void *p, size_t oldsize, size_t newsize,
-		gfp_t flags);
-extern void kvfree(const void *addr);
-extern void kvfree_sensitive(const void *addr, size_t len);
-
 static inline int head_compound_mapcount(struct page *head)
 {
 	return atomic_read(compound_mapcount_ptr(head)) + 1;

include/linux/slab.h

@@ -732,6 +732,40 @@ static inline void *kzalloc_node(size_t size, gfp_t flags, int node)
 	return kmalloc_node(size, flags | __GFP_ZERO, node);
 }
 
+extern void *kvmalloc_node(size_t size, gfp_t flags, int node);
+static inline void *kvmalloc(size_t size, gfp_t flags)
+{
+	return kvmalloc_node(size, flags, NUMA_NO_NODE);
+}
+static inline void *kvzalloc_node(size_t size, gfp_t flags, int node)
+{
+	return kvmalloc_node(size, flags | __GFP_ZERO, node);
+}
+static inline void *kvzalloc(size_t size, gfp_t flags)
+{
+	return kvmalloc(size, flags | __GFP_ZERO);
+}
+
+static inline void *kvmalloc_array(size_t n, size_t size, gfp_t flags)
+{
+	size_t bytes;
+
+	if (unlikely(check_mul_overflow(n, size, &bytes)))
+		return NULL;
+
+	return kvmalloc(bytes, flags);
+}
+
+static inline void *kvcalloc(size_t n, size_t size, gfp_t flags)
+{
+	return kvmalloc_array(n, size, flags | __GFP_ZERO);
+}
+
+extern void *kvrealloc(const void *p, size_t oldsize, size_t newsize,
+		gfp_t flags);
+extern void kvfree(const void *addr);
+extern void kvfree_sensitive(const void *addr, size_t len);
+
 unsigned int kmem_cache_size(struct kmem_cache *s);
 void __init kmem_cache_init_late(void);