X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=drivers%2Fmd%2Fdm-target.c;h=11dea11dc0b649e16594e071163f79647c274293;hp=477a041a41cfa4601cb796ddf14df3dfcdbde562;hb=5a0e3ad6af8660be21ca98a971cd00f331318c05;hpb=72d9486169a2a8353e022813185ba2f32d7dde69 diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c index 477a041..11dea11 100644 --- a/drivers/md/dm-target.c +++ b/drivers/md/dm-target.c @@ -10,49 +10,37 @@ #include #include #include -#include #define DM_MSG_PREFIX "target" -struct tt_internal { - struct target_type tt; - - struct list_head list; - long use; -}; - static LIST_HEAD(_targets); static DECLARE_RWSEM(_lock); #define DM_MOD_NAME_SIZE 32 -static inline struct tt_internal *__find_target_type(const char *name) +static inline struct target_type *__find_target_type(const char *name) { - struct tt_internal *ti; + struct target_type *tt; - list_for_each_entry (ti, &_targets, list) - if (!strcmp(name, ti->tt.name)) - return ti; + list_for_each_entry(tt, &_targets, list) + if (!strcmp(name, tt->name)) + return tt; return NULL; } -static struct tt_internal *get_target_type(const char *name) +static struct target_type *get_target_type(const char *name) { - struct tt_internal *ti; + struct target_type *tt; down_read(&_lock); - ti = __find_target_type(name); - if (ti) { - if ((ti->use == 0) && !try_module_get(ti->tt.module)) - ti = NULL; - else - ti->use++; - } + tt = __find_target_type(name); + if (tt && !try_module_get(tt->module)) + tt = NULL; up_read(&_lock); - return ti; + return tt; } static void load_module(const char *name) @@ -62,113 +50,78 @@ static void load_module(const char *name) struct target_type *dm_get_target_type(const char *name) { - struct tt_internal *ti = get_target_type(name); + struct target_type *tt = get_target_type(name); - if (!ti) { + if (!tt) { load_module(name); - ti = get_target_type(name); + tt = get_target_type(name); } - return ti ? &ti->tt : NULL; + return tt; } -void dm_put_target_type(struct target_type *t) +void dm_put_target_type(struct target_type *tt) { - struct tt_internal *ti = (struct tt_internal *) t; - down_read(&_lock); - if (--ti->use == 0) - module_put(ti->tt.module); - - BUG_ON(ti->use < 0); + module_put(tt->module); up_read(&_lock); - - return; } -static struct tt_internal *alloc_target(struct target_type *t) -{ - struct tt_internal *ti = kmalloc(sizeof(*ti), GFP_KERNEL); - - if (ti) { - memset(ti, 0, sizeof(*ti)); - ti->tt = *t; - } - - return ti; -} - - int dm_target_iterate(void (*iter_func)(struct target_type *tt, void *param), void *param) { - struct tt_internal *ti; + struct target_type *tt; down_read(&_lock); - list_for_each_entry (ti, &_targets, list) - iter_func(&ti->tt, param); + list_for_each_entry(tt, &_targets, list) + iter_func(tt, param); up_read(&_lock); return 0; } -int dm_register_target(struct target_type *t) +int dm_register_target(struct target_type *tt) { int rv = 0; - struct tt_internal *ti = alloc_target(t); - - if (!ti) - return -ENOMEM; down_write(&_lock); - if (__find_target_type(t->name)) + if (__find_target_type(tt->name)) rv = -EEXIST; else - list_add(&ti->list, &_targets); + list_add(&tt->list, &_targets); up_write(&_lock); - if (rv) - kfree(ti); return rv; } -int dm_unregister_target(struct target_type *t) +void dm_unregister_target(struct target_type *tt) { - struct tt_internal *ti; - down_write(&_lock); - if (!(ti = __find_target_type(t->name))) { - up_write(&_lock); - return -EINVAL; - } - - if (ti->use) { - up_write(&_lock); - return -ETXTBSY; + if (!__find_target_type(tt->name)) { + DMCRIT("Unregistering unrecognised target: %s", tt->name); + BUG(); } - list_del(&ti->list); - kfree(ti); + list_del(&tt->list); up_write(&_lock); - return 0; } /* * io-err: always fails an io, useful for bringing * up LVs that have holes in them. */ -static int io_err_ctr(struct dm_target *ti, unsigned int argc, char **args) +static int io_err_ctr(struct dm_target *tt, unsigned int argc, char **args) { return 0; } -static void io_err_dtr(struct dm_target *ti) +static void io_err_dtr(struct dm_target *tt) { /* empty */ } -static int io_err_map(struct dm_target *ti, struct bio *bio, +static int io_err_map(struct dm_target *tt, struct bio *bio, union map_info *map_context) { return -EIO; @@ -189,8 +142,7 @@ int __init dm_target_init(void) void dm_target_exit(void) { - if (dm_unregister_target(&error_target)) - DMWARN("error target unregistration failed"); + dm_unregister_target(&error_target); } EXPORT_SYMBOL(dm_register_target);