To: Andrew Morton <akpm@osdl.org>
Cc: linux-kernel@vger.kernel.org, Bryn Reeves <breeves@redhat.com>
Subject: [PATCH 24/25] dm: extract device limit setting
From: Bryn Reeves <breeves@redhat.com>
Separate the setting of device I/O limits from dm_get_device().
dm-loop will use this.
Signed-off-by: Bryn Reeves <breeves@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Index: linux-2.6.18-rc7/drivers/md/dm-table.c
===================================================================
--- linux-2.6.18-rc7.orig/drivers/md/dm-table.c 2006-10-13 17:10:13.000000000 +0100
+++ linux-2.6.18-rc7/drivers/md/dm-table.c 2006-10-13 17:10:16.000000000 +0100
@@ -522,56 +522,61 @@ static int __table_get_device(struct dm_
return 0;
}
+void dm_set_device_limits(struct dm_target *ti, struct block_device *bdev)
+{
+ request_queue_t *q = bdev_get_queue(bdev);
+ struct io_restrictions *rs = &ti->limits;
+
+ /*
+ * Combine the device limits low.
+ *
+ * FIXME: if we move an io_restriction struct
+ * into q this would just be a call to
+ * combine_restrictions_low()
+ */
+ rs->max_sectors =
+ min_not_zero(rs->max_sectors, q->max_sectors);
+
+ /* FIXME: Device-Mapper on top of RAID-0 breaks because DM
+ * currently doesn't honor MD's merge_bvec_fn routine.
+ * In this case, we'll force DM to use PAGE_SIZE or
+ * smaller I/O, just to be safe. A better fix is in the
+ * works, but add this for the time being so it will at
+ * least operate correctly.
+ */
+ if (q->merge_bvec_fn)
+ rs->max_sectors =
+ min_not_zero(rs->max_sectors,
+ (unsigned int) (PAGE_SIZE >> 9));
+
+ rs->max_phys_segments =
+ min_not_zero(rs->max_phys_segments,
+ q->max_phys_segments);
+
+ rs->max_hw_segments =
+ min_not_zero(rs->max_hw_segments, q->max_hw_segments);
+
+ rs->hardsect_size = max(rs->hardsect_size, q->hardsect_size);
+
+ rs->max_segment_size =
+ min_not_zero(rs->max_segment_size, q->max_segment_size);
+
+ rs->seg_boundary_mask =
+ min_not_zero(rs->seg_boundary_mask,
+ q->seg_boundary_mask);
+
+ rs->no_cluster |= !test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags);
+}
+EXPORT_SYMBOL_GPL(dm_set_device_limits);
int dm_get_device(struct dm_target *ti, const char *path, sector_t start,
sector_t len, int mode, struct dm_dev **result)
{
int r = __table_get_device(ti->table, ti, path,
start, len, mode, result);
- if (!r) {
- request_queue_t *q = bdev_get_queue((*result)->bdev);
- struct io_restrictions *rs = &ti->limits;
-
- /*
- * Combine the device limits low.
- *
- * FIXME: if we move an io_restriction struct
- * into q this would just be a call to
- * combine_restrictions_low()
- */
- rs->max_sectors =
- min_not_zero(rs->max_sectors, q->max_sectors);
- /* FIXME: Device-Mapper on top of RAID-0 breaks because DM
- * currently doesn't honor MD's merge_bvec_fn routine.
- * In this case, we'll force DM to use PAGE_SIZE or
- * smaller I/O, just to be safe. A better fix is in the
- * works, but add this for the time being so it will at
- * least operate correctly.
- */
- if (q->merge_bvec_fn)
- rs->max_sectors =
- min_not_zero(rs->max_sectors,
- (unsigned int) (PAGE_SIZE >> 9));
-
- rs->max_phys_segments =
- min_not_zero(rs->max_phys_segments,
- q->max_phys_segments);
-
- rs->max_hw_segments =
- min_not_zero(rs->max_hw_segments, q->max_hw_segments);
-
- rs->hardsect_size = max(rs->hardsect_size, q->hardsect_size);
-
- rs->max_segment_size =
- min_not_zero(rs->max_segment_size, q->max_segment_size);
-
- rs->seg_boundary_mask =
- min_not_zero(rs->seg_boundary_mask,
- q->seg_boundary_mask);
-
- rs->no_cluster |= !test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags);
- }
+ if (!r)
+ dm_set_device_limits(ti, (*result)->bdev);
return r;
}
Index: linux-2.6.18-rc7/include/linux/device-mapper.h
===================================================================
--- linux-2.6.18-rc7.orig/include/linux/device-mapper.h 2006-10-13 17:10:13.000000000 +0100
+++ linux-2.6.18-rc7/include/linux/device-mapper.h 2006-10-13 17:10:16.000000000 +0100
@@ -72,6 +72,11 @@ typedef int (*dm_ioctl_fn) (struct dm_ta
void dm_error(const char *message);
/*
+ * Combine device limits.
+ */
+void dm_set_device_limits(struct dm_target *ti, struct block_device *bdev);
+
+/*
* Constructors should call these functions to ensure destination devices
* are opened/closed correctly.
* FIXME: too many arguments.