This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / mm / util.c

diff --git a/mm/util.c b/mm/util.c
new file mode 100644 (file)
index 0000000..7368479
--- /dev/null
+++ b/mm/util.c
@@ -0,0 +1,76 @@
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <asm/uaccess.h>
+
+/**
+ * __kzalloc - allocate memory. The memory is set to zero.
+ * @size: how many bytes of memory are required.
+ * @flags: the type of memory to allocate.
+ */
+void *__kzalloc(size_t size, gfp_t flags)
+{
+       void *ret = ____kmalloc(size, flags);
+       if (ret)
+               memset(ret, 0, size);
+       return ret;
+}
+EXPORT_SYMBOL(__kzalloc);
+
+/*
+ * kstrdup - allocate space for and copy an existing string
+ *
+ * @s: the string to duplicate
+ * @gfp: the GFP mask used in the kmalloc() call when allocating memory
+ */
+char *kstrdup(const char *s, gfp_t gfp)
+{
+       size_t len;
+       char *buf;
+
+       if (!s)
+               return NULL;
+
+       len = strlen(s) + 1;
+       buf = ____kmalloc(len, gfp);
+       if (buf)
+               memcpy(buf, s, len);
+       return buf;
+}
+EXPORT_SYMBOL(kstrdup);
+
+/*
+ * strndup_user - duplicate an existing string from user space
+ *
+ * @s: The string to duplicate
+ * @n: Maximum number of bytes to copy, including the trailing NUL.
+ */
+char *strndup_user(const char __user *s, long n)
+{
+       char *p;
+       long length;
+
+       length = strnlen_user(s, n);
+
+       if (!length)
+               return ERR_PTR(-EFAULT);
+
+       if (length > n)
+               return ERR_PTR(-EINVAL);
+
+       p = kmalloc(length, GFP_KERNEL);
+
+       if (!p)
+               return ERR_PTR(-ENOMEM);
+
+       if (copy_from_user(p, s, length)) {
+               kfree(p);
+               return ERR_PTR(-EFAULT);
+       }
+
+       p[length - 1] = '\0';
+
+       return p;
+}
+EXPORT_SYMBOL(strndup_user);