Re: [dm-devel] [PATCH 1/3] block: Add blk_queue_copy_limits()

["Martin K. Petersen" <martin.petersen@oracle.com>]

>>>>> "Jun'ichi" == Jun'ichi Nomura <j-nomura@ce.jp.nec.com> writes:

Jun'ichi> If we aren't sure, shouldn't we set its default to -1 or
Jun'ichi> putting comments in blk_set_default_limits() at least to avoid
Jun'ichi> possible confusion in future?

Jens, what do you think about this?  Goes on top of what you have
queued...


block: Do not clamp max_hw_sectors for stacking devices

Stacking devices do not have an inherent max_hw_sector limit.  Set the
default to INT_MAX so we are bounded only by capabilities of the
underlying storage.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

---

diff --git a/block/blk-settings.c b/block/blk-settings.c
index cd9b730..eaf122f 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -111,7 +111,8 @@ void blk_set_default_limits(struct queue_limits *lim)
 	lim->max_hw_segments = MAX_HW_SEGMENTS;
 	lim->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK;
 	lim->max_segment_size = MAX_SEGMENT_SIZE;
-	lim->max_sectors = lim->max_hw_sectors = BLK_DEF_MAX_SECTORS;
+	lim->max_sectors = BLK_DEF_MAX_SECTORS;
+	lim->max_hw_sectors = INT_MAX;
 	lim->logical_block_size = lim->physical_block_size = lim->io_min = 512;
 	lim->bounce_pfn = (unsigned long)(BLK_BOUNCE_ANY >> PAGE_SHIFT);
 	lim->alignment_offset = 0;