[PATCH v2 3/9] util: Introduce __kvmalloc_node() that can take kmem_buckets argument

From: Kees Cook
Date: Tue Mar 05 2024 - 05:11:03 EST


Provide an API to perform kvmalloc-style allocations with a particular
set of buckets.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Roman Gushchin <roman.gushchin@xxxxxxxxx>
Cc: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
Cc: linux-mm@xxxxxxxxx
---
include/linux/slab.h | 9 ++++++++-
mm/util.c | 9 +++++----
2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/include/linux/slab.h b/include/linux/slab.h
index 1cc1a7637b56..f26ac9a6ef9f 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -723,7 +723,14 @@ static inline __alloc_size(1) void *kzalloc_node(size_t size, gfp_t flags, int n
return kmalloc_node(size, flags | __GFP_ZERO, node);
}

-extern void *kvmalloc_node(size_t size, gfp_t flags, int node) __alloc_size(1);
+void * __alloc_size(2)
+__kvmalloc_node(kmem_buckets *b, size_t size, gfp_t flags, int node);
+
+static inline __alloc_size(1) void *kvmalloc_node(size_t size, gfp_t flags, int node)
+{
+ return __kvmalloc_node(NULL, size, flags, node);
+}
+
static inline __alloc_size(1) void *kvmalloc(size_t size, gfp_t flags)
{
return kvmalloc_node(size, flags, NUMA_NO_NODE);
diff --git a/mm/util.c b/mm/util.c
index 5a6a9802583b..02c895b87a28 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -577,8 +577,9 @@ unsigned long vm_mmap(struct file *file, unsigned long addr,
EXPORT_SYMBOL(vm_mmap);

/**
- * kvmalloc_node - attempt to allocate physically contiguous memory, but upon
+ * __kvmalloc_node - attempt to allocate physically contiguous memory, but upon
* failure, fall back to non-contiguous (vmalloc) allocation.
+ * @b: which set of kmalloc buckets to allocate from.
* @size: size of the request.
* @flags: gfp mask for the allocation - must be compatible (superset) with GFP_KERNEL.
* @node: numa node to allocate from
@@ -592,7 +593,7 @@ EXPORT_SYMBOL(vm_mmap);
*
* Return: pointer to the allocated memory of %NULL in case of failure
*/
-void *kvmalloc_node(size_t size, gfp_t flags, int node)
+void *__kvmalloc_node(kmem_buckets *b, size_t size, gfp_t flags, int node)
{
gfp_t kmalloc_flags = flags;
void *ret;
@@ -614,7 +615,7 @@ void *kvmalloc_node(size_t size, gfp_t flags, int node)
kmalloc_flags &= ~__GFP_NOFAIL;
}

- ret = kmalloc_node(size, kmalloc_flags, node);
+ ret = __kmalloc_node(b, size, kmalloc_flags, node);

/*
* It doesn't really make sense to fallback to vmalloc for sub page
@@ -643,7 +644,7 @@ void *kvmalloc_node(size_t size, gfp_t flags, int node)
flags, PAGE_KERNEL, VM_ALLOW_HUGE_VMAP,
node, __builtin_return_address(0));
}
-EXPORT_SYMBOL(kvmalloc_node);
+EXPORT_SYMBOL(__kvmalloc_node);

/**
* kvfree() - Free memory.
--
2.34.1