block: misc updates

This patch makes the following misc updates in preparation for
disk->part dereference fix and extended block devt support.

* implment part_to_disk()

* fix comment about gendisk->part indexing

* rename get_part() to disk_map_sector()

* don't use n which is always zero while printing disk information in
  diskstats_show()

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Tejun Heo
2008-08-25 19:47:17 +09:00
committed by Jens Axboe
parent 88e341261c
commit 310a2c1012
5 changed files with 19 additions and 11 deletions

View File

@@ -116,7 +116,7 @@ struct gendisk {
int minors; /* maximum number of minors, =1 for
* disks that can't be partitioned. */
char disk_name[32]; /* name of major driver */
struct hd_struct **part; /* [indexed by minor] */
struct hd_struct **part; /* [indexed by minor - 1] */
struct block_device_operations *fops;
struct request_queue *queue;
void *private_data;
@@ -145,14 +145,21 @@ struct gendisk {
#endif
};
static inline struct gendisk *part_to_disk(struct hd_struct *part)
{
if (likely(part))
return dev_to_disk((part)->dev.parent);
return NULL;
}
/*
* Macros to operate on percpu disk statistics:
*
* The __ variants should only be called in critical sections. The full
* variants disable/enable preemption.
*/
static inline struct hd_struct *get_part(struct gendisk *gendiskp,
sector_t sector)
static inline struct hd_struct *disk_map_sector(struct gendisk *gendiskp,
sector_t sector)
{
struct hd_struct *part;
int i;