arch/um/kernel/initrd.c

   1 /*
   2  * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/init.h"
   7 #include "linux/bootmem.h"
   8 #include "linux/initrd.h"
   9 #include "asm/types.h"
  10 #include "kern_util.h"
  11 #include "initrd.h"
  12 #include "init.h"
  13 #include "os.h"
  14
  15 /* Changed by uml_initrd_setup, which is a setup */
  16 static char *initrd __initdata = NULL;
  17
  18 static int __init read_initrd(void)
  19 {
  20         void *area;
  21         long long size;
  22         int err;
  23
  24         if(initrd == NULL) return 0;
  25         err = os_file_size(initrd, &size);
  26         if(err) return 0;
  27         area = alloc_bootmem(size);
  28         if(area == NULL) return 0;
  29         if(load_initrd(initrd, area, size) == -1) return 0;
  30         initrd_start = (unsigned long) area;
  31         initrd_end = initrd_start + size;
  32         return 0;
  33 }
  34
  35 __uml_postsetup(read_initrd);
  36
  37 static int __init uml_initrd_setup(char *line, int *add)
  38 {
  39         initrd = line;
  40         return 0;
  41 }
  42
  43 __uml_setup("initrd=", uml_initrd_setup,
  44 "initrd=<initrd image>\n"
  45 "    This is used to boot UML from an initrd image.  The argument is the\n"
  46 "    name of the file containing the image.\n\n"
  47 );
  48
  49 int load_initrd(char *filename, void *buf, int size)
  50 {
  51         int fd, n;
  52
  53         fd = os_open_file(filename, of_read(OPENFLAGS()), 0);
  54         if(fd < 0){
  55                 printk("Opening '%s' failed - err = %d\n", filename, -fd);
  56                 return(-1);
  57         }
  58         n = os_read_file_k(fd, buf, size);
  59         if(n != size){
  60                 printk("Read of %d bytes from '%s' failed, err = %d\n", size,
  61                        filename, -n);
  62                 return(-1);
  63         }
  64
  65         os_close_file(fd);
  66         return(0);
  67 }
  68 /*
  69  * Overrides for Emacs so that we follow Linus's tabbing style.
  70  * Emacs will notice this stuff at the end of the file and automatically
  71  * adjust the settings for this buffer only.  This must remain at the end
  72  * of the file.
  73  * ---------------------------------------------------------------------------
  74  * Local variables:
  75  * c-file-style: "linux"
  76  * End:
  77  */