ia64/linux-2.6.18-xen.hg

view drivers/mtd/chips/map_rom.c @ 893:f994bfe9b93b

linux/blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 04 10:32:57 2009 +0100 (2009-06-04)
parents 831230e53067
children
line source
1 /*
2 * Common code to handle map devices which are simple ROM
3 * (C) 2000 Red Hat. GPL'd.
4 * $Id: map_rom.c,v 1.23 2005/01/05 18:05:12 dwmw2 Exp $
5 */
7 #include <linux/module.h>
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <asm/io.h>
11 #include <asm/byteorder.h>
12 #include <linux/errno.h>
13 #include <linux/slab.h>
14 #include <linux/init.h>
15 #include <linux/mtd/mtd.h>
16 #include <linux/mtd/map.h>
17 #include <linux/mtd/compatmac.h>
19 static int maprom_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
20 static int maprom_write (struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
21 static void maprom_nop (struct mtd_info *);
22 static struct mtd_info *map_rom_probe(struct map_info *map);
24 static struct mtd_chip_driver maprom_chipdrv = {
25 .probe = map_rom_probe,
26 .name = "map_rom",
27 .module = THIS_MODULE
28 };
30 static struct mtd_info *map_rom_probe(struct map_info *map)
31 {
32 struct mtd_info *mtd;
34 mtd = kmalloc(sizeof(*mtd), GFP_KERNEL);
35 if (!mtd)
36 return NULL;
38 memset(mtd, 0, sizeof(*mtd));
40 map->fldrv = &maprom_chipdrv;
41 mtd->priv = map;
42 mtd->name = map->name;
43 mtd->type = MTD_ROM;
44 mtd->size = map->size;
45 mtd->read = maprom_read;
46 mtd->write = maprom_write;
47 mtd->sync = maprom_nop;
48 mtd->flags = MTD_CAP_ROM;
49 mtd->erasesize = map->size;
50 mtd->writesize = 1;
52 __module_get(THIS_MODULE);
53 return mtd;
54 }
57 static int maprom_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
58 {
59 struct map_info *map = mtd->priv;
61 map_copy_from(map, buf, from, len);
62 *retlen = len;
63 return 0;
64 }
66 static void maprom_nop(struct mtd_info *mtd)
67 {
68 /* Nothing to see here */
69 }
71 static int maprom_write (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf)
72 {
73 printk(KERN_NOTICE "maprom_write called\n");
74 return -EIO;
75 }
77 static int __init map_rom_init(void)
78 {
79 register_mtd_chip_driver(&maprom_chipdrv);
80 return 0;
81 }
83 static void __exit map_rom_exit(void)
84 {
85 unregister_mtd_chip_driver(&maprom_chipdrv);
86 }
88 module_init(map_rom_init);
89 module_exit(map_rom_exit);
91 MODULE_LICENSE("GPL");
92 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
93 MODULE_DESCRIPTION("MTD chip driver for ROM chips");