block: adjust formatting for large minors and add ext_range sysfs attr

With extended minors and the soon-to-follow debug feature, large minor
numbers for block devices will be common.  This patch does the
followings to make printouts pretty.

* Adapt print formats such that large minors don't break the
  formatting.

* For extended MAJ:MIN, %02x%02x for MAJ:MIN used in
  printk_all_partitions() doesn't cut it anymore.  Update it such that
  %03x:%05x is used if either MAJ or MIN doesn't fit in %02x.

* Implement ext_range sysfs attribute which shows total minors the
  device can use including both conventional minor space and the
  extended one.

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 19:47:23 +09:00 committed by Jens Axboe
parent bcce3de1be
commit 1f0142905d
2 changed files with 35 additions and 11 deletions

View file

@ -366,6 +366,18 @@ void blk_free_devt(dev_t devt)
}
}
static char *bdevt_str(dev_t devt, char *buf)
{
if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) {
char tbuf[BDEVT_SIZE];
snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt));
snprintf(buf, BDEVT_SIZE, "%-9s", tbuf);
} else
snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt));
return buf;
}
/*
* Register device numbers dev..(dev+range-1)
* range must be nonzero
@ -521,7 +533,8 @@ void __init printk_all_partitions(void)
struct gendisk *disk = dev_to_disk(dev);
struct disk_part_iter piter;
struct hd_struct *part;
char buf[BDEVNAME_SIZE];
char name_buf[BDEVNAME_SIZE];
char devt_buf[BDEVT_SIZE];
/*
* Don't show empty devices or things that have been
@ -536,10 +549,10 @@ void __init printk_all_partitions(void)
* numbers in hex - the same format as the root=
* option takes.
*/
printk("%02x%02x %10llu %s",
MAJOR(disk_devt(disk)), MINOR(disk_devt(disk)),
printk("%s %10llu %s",
bdevt_str(disk_devt(disk), devt_buf),
(unsigned long long)get_capacity(disk) >> 1,
disk_name(disk, 0, buf));
disk_name(disk, 0, name_buf));
if (disk->driverfs_dev != NULL &&
disk->driverfs_dev->driver != NULL)
printk(" driver: %s\n",
@ -550,10 +563,10 @@ void __init printk_all_partitions(void)
/* now show the partitions */
disk_part_iter_init(&piter, disk, 0);
while ((part = disk_part_iter_next(&piter)))
printk(" %02x%02x %10llu %s\n",
MAJOR(part_devt(part)), MINOR(part_devt(part)),
printk(" %s %10llu %s\n",
bdevt_str(part_devt(part), devt_buf),
(unsigned long long)part->nr_sects >> 1,
disk_name(disk, part->partno, buf));
disk_name(disk, part->partno, name_buf));
disk_part_iter_exit(&piter);
}
class_dev_iter_exit(&iter);
@ -630,14 +643,14 @@ static int show_partition(struct seq_file *seqf, void *v)
return 0;
/* show the full disk and all non-0 size partitions of it */
seq_printf(seqf, "%4d %4d %10llu %s\n",
seq_printf(seqf, "%4d %7d %10llu %s\n",
MAJOR(disk_devt(sgp)), MINOR(disk_devt(sgp)),
(unsigned long long)get_capacity(sgp) >> 1,
disk_name(sgp, 0, buf));
disk_part_iter_init(&piter, sgp, 0);
while ((part = disk_part_iter_next(&piter)))
seq_printf(seqf, "%4d %4d %10llu %s\n",
seq_printf(seqf, "%4d %7d %10llu %s\n",
MAJOR(part_devt(part)), MINOR(part_devt(part)),
(unsigned long long)part->nr_sects >> 1,
disk_name(sgp, part->partno, buf));
@ -691,6 +704,14 @@ static ssize_t disk_range_show(struct device *dev,
return sprintf(buf, "%d\n", disk->minors);
}
static ssize_t disk_ext_range_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct gendisk *disk = dev_to_disk(dev);
return sprintf(buf, "%d\n", disk_max_parts(disk) + 1);
}
static ssize_t disk_removable_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
@ -780,6 +801,7 @@ static ssize_t disk_fail_store(struct device *dev,
#endif
static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL);
static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
static DEVICE_ATTR(size, S_IRUGO, disk_size_show, NULL);
@ -792,6 +814,7 @@ static struct device_attribute dev_attr_fail =
static struct attribute *disk_attrs[] = {
&dev_attr_range.attr,
&dev_attr_ext_range.attr,
&dev_attr_removable.attr,
&dev_attr_ro.attr,
&dev_attr_size.attr,
@ -858,7 +881,7 @@ static int diskstats_show(struct seq_file *seqf, void *v)
cpu = disk_stat_lock();
disk_round_stats(cpu, gp);
disk_stat_unlock();
seq_printf(seqf, "%4d %4d %s %lu %lu %llu %u %lu %lu %llu %u %u %u %u\n",
seq_printf(seqf, "%4d %7d %s %lu %lu %llu %u %lu %lu %llu %u %u %u %u\n",
MAJOR(disk_devt(gp)), MINOR(disk_devt(gp)),
disk_name(gp, 0, buf),
disk_stat_read(gp, ios[0]), disk_stat_read(gp, merges[0]),
@ -877,7 +900,7 @@ static int diskstats_show(struct seq_file *seqf, void *v)
cpu = disk_stat_lock();
part_round_stats(cpu, hd);
disk_stat_unlock();
seq_printf(seqf, "%4d %4d %s %lu %lu %llu "
seq_printf(seqf, "%4d %7d %s %lu %lu %llu "
"%u %lu %lu %llu %u %u %u %u\n",
MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
disk_name(gp, hd->partno, buf),

View file

@ -1685,6 +1685,7 @@ extern void chrdev_show(struct seq_file *,off_t);
/* fs/block_dev.c */
#define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
#define BDEVT_SIZE 10 /* Largest string for MAJ:MIN for blkdev */
#ifdef CONFIG_BLOCK
#define BLKDEV_MAJOR_HASH_SIZE 255