include/linux/slab.h: add kmalloc_array_node() and kcalloc_node()

Patch series "Add kmalloc_array_node() and kcalloc_node()".

Our current memeory allocation routines suffer form an API imbalance,
for one we have kmalloc_array() and kcalloc() which check for overflows
in size multiplication and we have kmalloc_node() and kzalloc_node()
which allow for memory allocation on a certain NUMA node but don't check
for eventual overflows.

This patch (of 6):

We have kmalloc_array() and kcalloc() wrappers on top of kmalloc() which
ensure us overflow free multiplication for the size of a memory
allocation but these implementations are not NUMA-aware.

Likewise we have kmalloc_node() which is a NUMA-aware version of
kmalloc() but the implementation is not aware of any possible overflows
in eventual size calculations.

Introduce a combination of the two above cases to have a NUMA-node aware
version of kmalloc_array() and kcalloc().

Link: http://lkml.kernel.org/r/20170927082038.3782-2-jthumshirn@suse.deSigned-off-by: NJohannes Thumshirn <jthumshirn@suse.de>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: Damien Le Moal <damien.lemoal@wdc.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mike Marciniszyn <infinipath@intel.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

include/linux/slab.h

@@ -650,6 +650,22 @@ extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
 #define kmalloc_track_caller(size, flags) \
 	__kmalloc_track_caller(size, flags, _RET_IP_)
 
+static inline void *kmalloc_array_node(size_t n, size_t size, gfp_t flags,
+				       int node)
+{
+	if (size != 0 && n > SIZE_MAX / size)
+		return NULL;
+	if (__builtin_constant_p(n) && __builtin_constant_p(size))
+		return kmalloc_node(n * size, flags, node);
+	return __kmalloc_node(n * size, flags, node);
+}
+
+static inline void *kcalloc_node(size_t n, size_t size, gfp_t flags, int node)
+{
+	return kmalloc_array_node(n, size, flags | __GFP_ZERO, node);
+}
+
+
 #ifdef CONFIG_NUMA
 extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long);
 #define kmalloc_node_track_caller(size, flags, node) \