Commit db429e9e authored by Bartlomiej Zolnierkiewicz's avatar Bartlomiej Zolnierkiewicz
Browse files

partitions: add ->set_capacity block device method 



* Add ->set_capacity block device method and use it in rescan_partitions()
  to attempt enabling native capacity of the device upon detecting the
  partition which exceeds device capacity.

* Add GENHD_FL_NATIVE_CAPACITY flag to try limit attempts of enabling
  native capacity during partition scan.

Together with the consecutive patch implementing ->set_capacity method in
ide-gd device driver this allows automatic disabling of Host Protected Area
(HPA) if any partitions overlapping HPA are detected.

Cc: Robert Hancock <hancockrwd@gmail.com>
Cc: Frans Pop <elendil@planet.nl>
Cc: "Andries E. Brouwer" <Andries.Brouwer@cwi.nl>
Acked-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Emphatically-Acked-by: default avatarAlan Cox <alan@linux.intel.com>
Signed-off-by: default avatarBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
parent 02c33b12

fs/partitions/check.c

+32 −11
Original line number Diff line number Diff line
@@ -546,29 +546,50 @@ int rescan_partitions(struct gendisk *disk, struct block_device *bdev) 


	/* add partitions */

	for (p = 1; p < state->limit; p++) {

		sector_t size = state->parts[p].size;

		sector_t from = state->parts[p].from;

		sector_t size, from;

try_scan:

		size = state->parts[p].size;

		if (!size)

			continue;



		from = state->parts[p].from;

		if (from >= get_capacity(disk)) {

			printk(KERN_WARNING

			       "%s: p%d ignored, start %llu is behind the end of the disk\n",

			       disk->disk_name, p, (unsigned long long) from);

			continue;

		}



		if (from + size > get_capacity(disk)) {

			struct block_device_operations *bdops = disk->fops;

			unsigned long long capacity;



			printk(KERN_WARNING

			       "%s: p%d size %llu exceeds device capacity, ",

			       disk->disk_name, p, (unsigned long long) size);



			if (bdops->set_capacity &&

			    (disk->flags & GENHD_FL_NATIVE_CAPACITY) == 0) {

				printk(KERN_CONT "enabling native capacity\n");

				capacity = bdops->set_capacity(disk, ~0ULL);

				disk->flags |= GENHD_FL_NATIVE_CAPACITY;

				if (capacity > get_capacity(disk)) {

					set_capacity(disk, capacity);

					check_disk_size_change(disk, bdev);

					bdev->bd_invalidated = 0;

				}

				goto try_scan;

			} else {

				/*

				 * we can not ignore partitions of broken tables

			 * created by for example camera firmware, but we

			 * limit them to the end of the disk to avoid

				 * created by for example camera firmware, but

				 * we limit them to the end of the disk to avoid

				 * creating invalid block devices

				 */

			printk(KERN_WARNING

			       "%s: p%d size %llu exceeds device capacity, "

			       "limited to end of disk\n",

			       disk->disk_name, p, (unsigned long long) size);

				printk(KERN_CONT "limited to end of disk\n");

				size = get_capacity(disk) - from;

			}

		}

		part = add_partition(disk, p, from, size,

				     state->parts[p].flags);

		if (IS_ERR(part)) {

include/linux/blkdev.h

+2 −0
Original line number Diff line number Diff line
@@ -1106,6 +1106,8 @@ struct block_device_operations { 
	int (*direct_access) (struct block_device *, sector_t,

						void **, unsigned long *);

	int (*media_changed) (struct gendisk *);

	unsigned long long (*set_capacity) (struct gendisk *,

						unsigned long long);

	int (*revalidate_disk) (struct gendisk *);

	int (*getgeo)(struct block_device *, struct hd_geometry *);

	struct module *owner;

include/linux/genhd.h

+1 −0
Original line number Diff line number Diff line
@@ -113,6 +113,7 @@ struct hd_struct { 
#define GENHD_FL_UP				16

#define GENHD_FL_SUPPRESS_PARTITION_INFO	32

#define GENHD_FL_EXT_DEVT			64 /* allow extended devt */

#define GENHD_FL_NATIVE_CAPACITY		128



#define BLK_SCSI_MAX_CMDS	(256)

#define BLK_SCSI_CMD_PER_LONG	(BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))

CRA Git | Maintained and supported by SUSTech CRA and CCSE