block: add internal hd part table references

We can't use krefs since it's apparently restricted to very basic
reference counting.

This reverts commit e4a683c8.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
This commit is contained in:
Jens Axboe 2011-01-07 08:43:37 +01:00
parent 09e099d4ba
commit 6c23a9681c
7 changed files with 34 additions and 25 deletions

View File

@ -70,7 +70,7 @@ static void drive_stat_acct(struct request *rq, int new_io)
part_stat_inc(cpu, part, merges[rw]);
} else {
part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq));
if (!kref_test_and_get(&part->ref)) {
if (!hd_struct_try_get(part)) {
/*
* The partition is already being removed,
* the request will be accounted on the disk only
@ -80,7 +80,7 @@ static void drive_stat_acct(struct request *rq, int new_io)
* it as any other partition.
*/
part = &rq->rq_disk->part0;
kref_get(&part->ref);
hd_struct_get(part);
}
part_round_stats(cpu, part);
part_inc_in_flight(part, rw);
@ -1818,7 +1818,7 @@ static void blk_account_io_done(struct request *req)
part_round_stats(cpu, part);
part_dec_in_flight(part, rw);
kref_put(&part->ref, __delete_partition);
hd_struct_put(part);
part_stat_unlock();
}
}

View File

@ -356,7 +356,7 @@ static void blk_account_io_merge(struct request *req)
part_round_stats(cpu, part);
part_dec_in_flight(part, rq_data_dir(req));
kref_put(&part->ref, __delete_partition);
hd_struct_put(part);
part_stat_unlock();
}
}

View File

@ -1192,7 +1192,8 @@ struct gendisk *alloc_disk_node(int minors, int node_id)
return NULL;
}
disk->part_tbl->part[0] = &disk->part0;
kref_init(&disk->part0.ref);
hd_ref_init(&disk->part0);
disk->minors = minors;
rand_initialize_disk(disk);

View File

@ -381,10 +381,8 @@ static void delete_partition_rcu_cb(struct rcu_head *head)
put_device(part_to_dev(part));
}
void __delete_partition(struct kref *ref)
void __delete_partition(struct hd_struct *part)
{
struct hd_struct *part = container_of(ref, struct hd_struct, ref);
call_rcu(&part->rcu_head, delete_partition_rcu_cb);
}
@ -406,7 +404,7 @@ void delete_partition(struct gendisk *disk, int partno)
kobject_put(part->holder_dir);
device_del(part_to_dev(part));
kref_put(&part->ref, __delete_partition);
hd_struct_put(part);
}
static ssize_t whole_disk_show(struct device *dev,
@ -505,7 +503,7 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno,
if (!dev_get_uevent_suppress(ddev))
kobject_uevent(&pdev->kobj, KOBJ_ADD);
kref_init(&p->ref);
hd_ref_init(p);
return p;
out_free_info:

View File

@ -115,8 +115,8 @@ struct hd_struct {
#else
struct disk_stats dkstats;
#endif
atomic_t ref;
struct rcu_head rcu_head;
struct kref ref;
};
#define GENHD_FL_REMOVABLE 1
@ -584,7 +584,7 @@ extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
sector_t len, int flags,
struct partition_meta_info
*info);
extern void __delete_partition(struct kref *ref);
extern void __delete_partition(struct hd_struct *);
extern void delete_partition(struct gendisk *, int);
extern void printk_all_partitions(void);
@ -613,6 +613,29 @@ extern ssize_t part_fail_store(struct device *dev,
const char *buf, size_t count);
#endif /* CONFIG_FAIL_MAKE_REQUEST */
static inline void hd_ref_init(struct hd_struct *part)
{
atomic_set(&part->ref, 1);
smp_mb();
}
static inline void hd_struct_get(struct hd_struct *part)
{
atomic_inc(&part->ref);
smp_mb__after_atomic_inc();
}
static inline int hd_struct_try_get(struct hd_struct *part)
{
return atomic_inc_not_zero(&part->ref);
}
static inline void hd_struct_put(struct hd_struct *part)
{
if (atomic_dec_and_test(&part->ref))
__delete_partition(part);
}
#else /* CONFIG_BLOCK */
static inline void printk_all_partitions(void) { }

View File

@ -23,7 +23,6 @@ struct kref {
void kref_init(struct kref *kref);
void kref_get(struct kref *kref);
int kref_test_and_get(struct kref *kref);
int kref_put(struct kref *kref, void (*release) (struct kref *kref));
#endif /* _KREF_H_ */

View File

@ -36,18 +36,6 @@ void kref_get(struct kref *kref)
smp_mb__after_atomic_inc();
}
/**
* kref_test_and_get - increment refcount for object only if refcount is not
* zero.
* @kref: object.
*
* Return non-zero if the refcount was incremented, 0 otherwise
*/
int kref_test_and_get(struct kref *kref)
{
return atomic_inc_not_zero(&kref->refcount);
}
/**
* kref_put - decrement refcount for object.
* @kref: object.