Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / arch / um / kernel / initrd.c

diff --git a/kernel/arch/um/kernel/initrd.c b/kernel/arch/um/kernel/initrd.c
new file mode 100644 (file)
index 0000000..55cead8
--- /dev/null
+++ b/kernel/arch/um/kernel/initrd.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Licensed under the GPL
+ */
+
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/initrd.h>
+#include <asm/types.h>
+#include <init.h>
+#include <os.h>
+
+/* Changed by uml_initrd_setup, which is a setup */
+static char *initrd __initdata = NULL;
+static int load_initrd(char *filename, void *buf, int size);
+
+static int __init read_initrd(void)
+{
+       void *area;
+       long long size;
+       int err;
+
+       if (initrd == NULL)
+               return 0;
+
+       err = os_file_size(initrd, &size);
+       if (err)
+               return 0;
+
+       /*
+        * This is necessary because alloc_bootmem craps out if you
+        * ask for no memory.
+        */
+       if (size == 0) {
+               printk(KERN_ERR "\"%s\" is a zero-size initrd\n", initrd);
+               return 0;
+       }
+
+       area = alloc_bootmem(size);
+       if (area == NULL)
+               return 0;
+
+       if (load_initrd(initrd, area, size) == -1)
+               return 0;
+
+       initrd_start = (unsigned long) area;
+       initrd_end = initrd_start + size;
+       return 0;
+}
+
+__uml_postsetup(read_initrd);
+
+static int __init uml_initrd_setup(char *line, int *add)
+{
+       initrd = line;
+       return 0;
+}
+
+__uml_setup("initrd=", uml_initrd_setup,
+"initrd=<initrd image>\n"
+"    This is used to boot UML from an initrd image.  The argument is the\n"
+"    name of the file containing the image.\n\n"
+);
+
+static int load_initrd(char *filename, void *buf, int size)
+{
+       int fd, n;
+
+       fd = os_open_file(filename, of_read(OPENFLAGS()), 0);
+       if (fd < 0) {
+               printk(KERN_ERR "Opening '%s' failed - err = %d\n", filename,
+                      -fd);
+               return -1;
+       }
+       n = os_read_file(fd, buf, size);
+       if (n != size) {
+               printk(KERN_ERR "Read of %d bytes from '%s' failed, "
+                      "err = %d\n", size,
+                      filename, -n);
+               return -1;
+       }
+
+       os_close_file(fd);
+       return 0;
+}