Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6

[sfrench/cifs-2.6.git] / mm / util.c

diff --git a/mm/util.c b/mm/util.c
index 5f4bb59da63c5938a166023f963b985b9ecaf3cb..ace2aea69f1a834ca7526a1bfa4070205b82579e 100644 (file)
--- a/mm/util.c
+++ b/mm/util.c
@@ -1,20 +1,22 @@
 #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.
+ * __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 *__kzalloc(size_t size, gfp_t flags)
 {
-       void *ret = kmalloc(size, flags);
+       void *ret = kmalloc_track_caller(size, flags);
        if (ret)
                memset(ret, 0, size);
        return ret;
 }
-EXPORT_SYMBOL(kzalloc);
+EXPORT_SYMBOL(__kzalloc);
 
 /*
  * kstrdup - allocate space for and copy an existing string
@@ -31,9 +33,62 @@ char *kstrdup(const char *s, gfp_t gfp)
                return NULL;
 
        len = strlen(s) + 1;
-       buf = kmalloc(len, gfp);
+       buf = kmalloc_track_caller(len, gfp);
        if (buf)
                memcpy(buf, s, len);
        return buf;
 }
 EXPORT_SYMBOL(kstrdup);
+
+/**
+ * kmemdup - duplicate region of memory
+ *
+ * @src: memory region to duplicate
+ * @len: memory region length
+ * @gfp: GFP mask to use
+ */
+void *kmemdup(const void *src, size_t len, gfp_t gfp)
+{
+       void *p;
+
+       p = kmalloc_track_caller(len, gfp);
+       if (p)
+               memcpy(p, src, len);
+       return p;
+}
+EXPORT_SYMBOL(kmemdup);
+
+/*
+ * 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);