Merge branch 'for-3.6/core' of git://git.kernel.dk/linux-block

Pull core block IO bits from Jens Axboe:
 "The most complicated part if this is the request allocation rework by
  Tejun, which has been queued up for a long time and has been in
  for-next ditto as well.

  There are a few commits from yesterday and today, mostly trivial and
  obvious fixes.  So I'm pretty confident that it is sound.  It's also
  smaller than usual."

* 'for-3.6/core' of git://git.kernel.dk/linux-block:
  block: remove dead func declaration
  block: add partition resize function to blkpg ioctl
  block: uninitialized ioc->nr_tasks triggers WARN_ON
  block: do not artificially constrain max_sectors for stacking drivers
  blkcg: implement per-blkg request allocation
  block: prepare for multiple request_lists
  block: add q->nr_rqs[] and move q->rq.elvpriv to q->nr_rqs_elvpriv
  blkcg: inline bio_blkcg() and friends
  block: allocate io_context upfront
  block: refactor get_request[_wait]()
  block: drop custom queue draining used by scsi_transport_{iscsi|fc}
  mempool: add @gfp_mask to mempool_create_node()
  blkcg: make root blkcg allocation use %GFP_KERNEL
  blkcg: __blkg_lookup_create() doesn't need radix preload

1 files changed, 56 insertions, 3 deletions

diff --git a/block/ioctl.c b/block/ioctl.c
index ba15b2dbfb98..4476e0e85d16 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -13,7 +13,7 @@ static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user
 {
 	struct block_device *bdevp;
 	struct gendisk *disk;
-	struct hd_struct *part;
+	struct hd_struct *part, *lpart;
 	struct blkpg_ioctl_arg a;
 	struct blkpg_partition p;
 	struct disk_part_iter piter;
@@ -36,8 +36,8 @@ static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user
 		case BLKPG_ADD_PARTITION:
 			start = p.start >> 9;
 			length = p.length >> 9;
-			/* check for fit in a hd_struct */ 
-			if (sizeof(sector_t) == sizeof(long) && 
+			/* check for fit in a hd_struct */
+			if (sizeof(sector_t) == sizeof(long) &&
 			    sizeof(long long) > sizeof(long)) {
 				long pstart = start, plength = length;
 				if (pstart != start || plength != length
@@ -92,6 +92,59 @@ static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user
 			bdput(bdevp);
 
 			return 0;
+		case BLKPG_RESIZE_PARTITION:
+			start = p.start >> 9;
+			/* new length of partition in bytes */
+			length = p.length >> 9;
+			/* check for fit in a hd_struct */
+			if (sizeof(sector_t) == sizeof(long) &&
+			    sizeof(long long) > sizeof(long)) {
+				long pstart = start, plength = length;
+				if (pstart != start || plength != length
+				    || pstart < 0 || plength < 0)
+					return -EINVAL;
+			}
+			part = disk_get_part(disk, partno);
+			if (!part)
+				return -ENXIO;
+			bdevp = bdget(part_devt(part));
+			if (!bdevp) {
+				disk_put_part(part);
+				return -ENOMEM;
+			}
+			mutex_lock(&bdevp->bd_mutex);
+			mutex_lock_nested(&bdev->bd_mutex, 1);
+			if (start != part->start_sect) {
+				mutex_unlock(&bdevp->bd_mutex);
+				mutex_unlock(&bdev->bd_mutex);
+				bdput(bdevp);
+				disk_put_part(part);
+				return -EINVAL;
+			}
+			/* overlap? */
+			disk_part_iter_init(&piter, disk,
+					    DISK_PITER_INCL_EMPTY);
+			while ((lpart = disk_part_iter_next(&piter))) {
+				if (lpart->partno != partno &&
+				   !(start + length <= lpart->start_sect ||
+				   start >= lpart->start_sect + lpart->nr_sects)
+				   ) {
+					disk_part_iter_exit(&piter);
+					mutex_unlock(&bdevp->bd_mutex);
+					mutex_unlock(&bdev->bd_mutex);
+					bdput(bdevp);
+					disk_put_part(part);
+					return -EBUSY;
+				}
+			}
+			disk_part_iter_exit(&piter);
+			part_nr_sects_write(part, (sector_t)length);
+			i_size_write(bdevp->bd_inode, p.length);
+			mutex_unlock(&bdevp->bd_mutex);
+			mutex_unlock(&bdev->bd_mutex);
+			bdput(bdevp);
+			disk_put_part(part);
+			return 0;
 		default:
 			return -EINVAL;
 	}