diff options
Diffstat (limited to 'drivers/md/dm-zero.c')
| -rw-r--r-- | drivers/md/dm-zero.c | 31 |
1 files changed, 17 insertions, 14 deletions
diff --git a/drivers/md/dm-zero.c b/drivers/md/dm-zero.c index 51c0639b248..b9a64bbce30 100644 --- a/drivers/md/dm-zero.c +++ b/drivers/md/dm-zero.c @@ -1,33 +1,39 @@ /* - * Copyright (C) 2003 Christophe Saout <christophe@saout.de> + * Copyright (C) 2003 Jana Saout <jana@saout.de> * * This file is released under the GPL. */ -#include "dm.h" +#include <linux/device-mapper.h> #include <linux/module.h> #include <linux/init.h> #include <linux/bio.h> +#define DM_MSG_PREFIX "zero" + /* * Construct a dummy mapping that only returns zeros */ static int zero_ctr(struct dm_target *ti, unsigned int argc, char **argv) { if (argc != 0) { - ti->error = "dm-zero: No arguments required"; + ti->error = "No arguments required"; return -EINVAL; } + /* + * Silently drop discards, avoiding -EOPNOTSUPP. + */ + ti->num_discard_bios = 1; + return 0; } /* * Return zeros only on reads */ -static int zero_map(struct dm_target *ti, struct bio *bio, - union map_info *map_context) +static int zero_map(struct dm_target *ti, struct bio *bio) { switch(bio_rw(bio)) { case READ: @@ -41,15 +47,15 @@ static int zero_map(struct dm_target *ti, struct bio *bio, break; } - bio_endio(bio, bio->bi_size, 0); + bio_endio(bio, 0); /* accepted bio, don't make new request */ - return 0; + return DM_MAPIO_SUBMITTED; } static struct target_type zero_target = { .name = "zero", - .version = {1, 0, 0}, + .version = {1, 1, 0}, .module = THIS_MODULE, .ctr = zero_ctr, .map = zero_map, @@ -60,22 +66,19 @@ static int __init dm_zero_init(void) int r = dm_register_target(&zero_target); if (r < 0) - DMERR("zero: register failed %d", r); + DMERR("register failed %d", r); return r; } static void __exit dm_zero_exit(void) { - int r = dm_unregister_target(&zero_target); - - if (r < 0) - DMERR("zero: unregister failed %d", r); + dm_unregister_target(&zero_target); } module_init(dm_zero_init) module_exit(dm_zero_exit) -MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); +MODULE_AUTHOR("Jana Saout <jana@saout.de>"); MODULE_DESCRIPTION(DM_NAME " dummy target returning zeros"); MODULE_LICENSE("GPL"); |