From: Alexander Ofitserov <oficerovas@xxxxxxxxxxxx>
From: Paolo Bonzini <pbonzini@xxxxxxxxxx>
commit a8749a35c399 ("mm: vmalloc: introduce array allocation functions")
Linux has dozens of occurrences of vmalloc(array_size()) and
vzalloc(array_size()). Allow to simplify the code by providing
vmalloc_array and vcalloc, as well as the underscored variants that let
the caller specify the GFP flags.
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Alexander Ofitserov <oficerovas@xxxxxxxxxxxx>
---
include/linux/vmalloc.h | 5 +++++
mm/util.c | 50 +++++++++++++++++++++++++++++++++++++++++
2 files changed, 55 insertions(+)
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 76dad53a410ac..0fd47f2f39eb0 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -112,6 +112,11 @@ extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
int node, const void *caller);
+extern void *__vmalloc_array(size_t n, size_t size, gfp_t flags);
+extern void *vmalloc_array(size_t n, size_t size);
+extern void *__vcalloc(size_t n, size_t size, gfp_t flags);
+extern void *vcalloc(size_t n, size_t size);
+
extern void vfree(const void *addr);
extern void vfree_atomic(const void *addr);
diff --git a/mm/util.c b/mm/util.c
index 25bfda774f6fd..7fd3c2bb3e4f5 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -686,6 +686,56 @@ static inline void *__page_rmapping(struct page *page)
return (void *)mapping;
}
+/**
+ * __vmalloc_array - allocate memory for a virtually contiguous array.
+ * @n: number of elements.
+ * @size: element size.
+ * @flags: the type of memory to allocate (see kmalloc).
+ */
+void *__vmalloc_array(size_t n, size_t size, gfp_t flags)
+{
+ size_t bytes;
+
+ if (unlikely(check_mul_overflow(n, size, &bytes)))
+ return NULL;
+ return __vmalloc(bytes, flags);
+}
+EXPORT_SYMBOL(__vmalloc_array);
+
+/**
+ * vmalloc_array - allocate memory for a virtually contiguous array.
+ * @n: number of elements.
+ * @size: element size.
+ */
+void *vmalloc_array(size_t n, size_t size)
+{
+ return __vmalloc_array(n, size, GFP_KERNEL);
+}
+EXPORT_SYMBOL(vmalloc_array);
+
+/**
+ * __vcalloc - allocate and zero memory for a virtually contiguous array.
+ * @n: number of elements.
+ * @size: element size.
+ * @flags: the type of memory to allocate (see kmalloc).
+ */
+void *__vcalloc(size_t n, size_t size, gfp_t flags)
+{
+ return __vmalloc_array(n, size, flags | __GFP_ZERO);
+}
+EXPORT_SYMBOL(__vcalloc);
+
+/**
+ * vcalloc - allocate and zero memory for a virtually contiguous array.
+ * @n: number of elements.
+ * @size: element size.
+ */
+void *vcalloc(size_t n, size_t size)
+{
+ return __vmalloc_array(n, size, GFP_KERNEL | __GFP_ZERO);
+}
+EXPORT_SYMBOL(vcalloc);
+
/* Neutral page->mapping pointer to address_space or anon_vma or other */
void *page_rmapping(struct page *page)
{
--
2.42.1
