apfs/linux-apfs
0
0
Fork 0
mirror of https://github.com/linux-apfs/linux-apfs.git synced 2026-05-01 15:00:59 -07:00
Code Issues Packages Projects Releases Wiki Activity

block: don't depend on consecutive minor space

Browse Source 
* Implement disk_devt() and part_devt() and use them to directly
  access devt instead of computing it from ->major and ->first_minor.

  Note that all references to ->major and ->first_minor outside of
  block layer is used to determine devt of the disk (the part0) and as
  ->major and ->first_minor will continue to represent devt for the
  disk, converting these users aren't strictly necessary.  However,
  convert them for consistency.

* Implement disk_max_parts() to avoid directly deferencing
  genhd->minors.

* Update bdget_disk() such that it doesn't assume consecutive minor
  space.

* Move devt computation from register_disk() to add_disk() and make it
  the only one (all other usages use the initially determined value).

These changes clean up the code and will help disk->part dereference
fix and extended block device numbers.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Tejun Heo
2008-09-03 09:01:48 +02:00
committed by Jens Axboe
parent cf771cb5a7
commit f331c0296f
16 changed files with 132 additions and 67 deletions
Download Patch File Download Diff File Expand all files Collapse all files
include/linux/genhd.h
+21 -6
View File
@@ -111,10 +111,14 @@ struct hd_struct {
#define GENHD_FL_FAIL 64
struct gendisk {
/* major, first_minor and minors are input parameters only,
* don't use directly. Use disk_devt() and disk_max_parts().
*/
int major; /* major number of driver */
int first_minor;
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 - 1] */
struct block_device_operations *fops;
@@ -152,6 +156,21 @@ static inline struct gendisk *part_to_disk(struct hd_struct *part)
return NULL;
}
static inline int disk_max_parts(struct gendisk *disk)
{
return disk->minors - 1;
}
static inline dev_t disk_devt(struct gendisk *disk)
{
return disk->dev.devt;
}
static inline dev_t part_devt(struct hd_struct *part)
{
return part->dev.devt;
}
/*
* Macros to operate on percpu disk statistics:
*
@@ -163,7 +182,7 @@ static inline struct hd_struct *disk_map_sector(struct gendisk *gendiskp,
{
struct hd_struct *part;
int i;
for (i = 0; i < gendiskp->minors - 1; i++) {
for (i = 0; i < disk_max_parts(gendiskp); i++) {
part = gendiskp->part[i];
if (part && part->start_sect <= sector
&& sector < part->start_sect + part->nr_sects)
@@ -366,6 +385,7 @@ extern void add_disk(struct gendisk *disk);
extern void del_gendisk(struct gendisk *gp);
extern void unlink_gendisk(struct gendisk *gp);
extern struct gendisk *get_gendisk(dev_t dev, int *partno);
extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
extern void set_device_ro(struct block_device *bdev, int flag);
extern void set_disk_ro(struct gendisk *disk, int flag);
@@ -553,11 +573,6 @@ extern void blk_register_region(dev_t devt, unsigned long range,
void *data);
extern void blk_unregister_region(dev_t devt, unsigned long range);
static inline struct block_device *bdget_disk(struct gendisk *disk, int partno)
{
return bdget(MKDEV(disk->major, disk->first_minor) + partno);
}
#else /* CONFIG_BLOCK */
static inline void printk_all_partitions(void) { }