Commit 6c23a968 authored by Jens Axboe's avatar Jens Axboe
Browse files

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: default avatarJens Axboe <jaxboe@fusionio.com>
parent 09e099d4

block/blk-core.c

+3 −3
Original line number Diff line number Diff line
@@ -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();

	}

}

block/blk-merge.c

+1 −1
Original line number Diff line number Diff line
@@ -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();

	}

}

block/genhd.c

+2 −1
Original line number Diff line number Diff line
@@ -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);

fs/partitions/check.c

+3 −5
Original line number Diff line number Diff line
@@ -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:

include/linux/genhd.h

+25 −2
Original line number Diff line number Diff line
@@ -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) { }