ubifs-utils: Add linux kernel memory allocation implementations

Add linux kernel memory allocation implementations, because there are many
memory allocations(eg. kmalloc, kzalloc) used in UBIFS linux kernel libs.

This is a preparation for replacing implementation of UBIFS utils with
linux kernel libs.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 64 insertions, 0 deletions

diff --git a/ubifs-utils/common/kmem.c b/ubifs-utils/common/kmem.c
new file mode 100644
index 0000000..e926a13
--- /dev/null
+++ b/ubifs-utils/common/kmem.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Simple memory interface
+ */
+
+#include "compiler_attributes.h"
+#include "linux_types.h"
+#include "kmem.h"
+#include "defs.h"
+
+static void *kmem_alloc(size_t size)
+{
+	void *ptr = malloc(size);
+
+	if (ptr == NULL)
+		sys_errmsg("malloc failed (%d bytes)", (int)size);
+	return ptr;
+}
+
+static void *kmem_zalloc(size_t size)
+{
+	void *ptr = kmem_alloc(size);
+
+	if (!ptr)
+		return ptr;
+
+	memset(ptr, 0, size);
+	return ptr;
+}
+
+void *kmalloc(size_t size, gfp_t flags)
+{
+	if (flags & __GFP_ZERO)
+		return kmem_zalloc(size);
+	return kmem_alloc(size);
+}
+
+void *krealloc(void *ptr, size_t new_size, __unused gfp_t flags)
+{
+	ptr = realloc(ptr, new_size);
+	if (ptr == NULL)
+		sys_errmsg("realloc failed (%d bytes)", (int)new_size);
+	return ptr;
+}
+
+void *kmalloc_array(size_t n, size_t size, gfp_t flags)
+{
+	size_t bytes;
+
+	if (unlikely(check_mul_overflow(n, size, &bytes)))
+		return NULL;
+	return kmalloc(bytes, flags);
+}
+
+void *kmemdup(const void *src, size_t len, gfp_t gfp)
+{
+	void *p;
+
+	p = kmalloc(len, gfp);
+	if (p)
+		memcpy(p, src, len);
+
+	return p;
+}