forked from luck/tmp_suning_uos_patched
dm target: remove struct tt_internal
The tt_internal is really just a list_head to manage registered target_type in a double linked list, Here embed the list_head into target_type directly, 1. to avoid kmalloc/kfree; 2. then tt_internal is really unneeded; Cc: stable@kernel.org Signed-off-by: Cheng Renquan <crquan@gmail.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Reviewed-by: Alasdair G Kergon <agk@redhat.com>
This commit is contained in:
Cheng Renquan
Alasdair G Kergon
parent
570b9d968b
commit
45194e4f89
|
|
@ -14,40 +14,34 @@
|
|||
|
||||
#define DM_MSG_PREFIX "target"
|
||||
|
||||
struct tt_internal {
|
||||
struct target_type tt;
|
||||
|
||||
struct list_head list;
|
||||
};
|
||||
|
||||
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 && !try_module_get(ti->tt.module))
|
||||
ti = NULL;
|
||||
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)
|
||||
|
|
@ -57,83 +51,59 @@ 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);
|
||||
module_put(ti->tt.module);
|
||||
module_put(tt->module);
|
||||
up_read(&_lock);
|
||||
|
||||
return;
|
||||
}
|
||||
|
||||
static struct tt_internal *alloc_target(struct target_type *t)
|
||||
{
|
||||
struct tt_internal *ti = kzalloc(sizeof(*ti), GFP_KERNEL);
|
||||
|
||||
if (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;
|
||||
}
|
||||
|
||||
void 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))) {
|
||||
DMCRIT("Unregistering unrecognised target: %s", t->name);
|
||||
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);
|
||||
}
|
||||
|
|
@ -142,17 +112,17 @@ void dm_unregister_target(struct target_type *t)
|
|||
* 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;
|
||||
|
|
|
|||
|
|
@ -60,7 +60,7 @@ int dm_table_barrier_ok(struct dm_table *t);
|
|||
int dm_target_init(void);
|
||||
void dm_target_exit(void);
|
||||
struct target_type *dm_get_target_type(const char *name);
|
||||
void dm_put_target_type(struct target_type *t);
|
||||
void dm_put_target_type(struct target_type *tt);
|
||||
int dm_target_iterate(void (*iter_func)(struct target_type *tt,
|
||||
void *param), void *param);
|
||||
|
||||
|
|
|
|||
|
|
@ -139,6 +139,9 @@ struct target_type {
|
|||
dm_ioctl_fn ioctl;
|
||||
dm_merge_fn merge;
|
||||
dm_busy_fn busy;
|
||||
|
||||
/* For internal device-mapper use. */
|
||||
struct list_head list;
|
||||
};
|
||||
|
||||
struct io_restrictions {
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user