block: set default max segment size in case of virt_boundary

For devices with virt_boundary limit, the driver may provide zero max
segment size, we have to set it as UINT_MAX at default. Otherwise, it
may cause warning in driver when handling sglist.

Fix it by setting default max segment size as UINT_MAX.

Cc: Christoph Hellwig <[email protected]>
Cc: Mike Snitzer <[email protected]>
Fixes: b561ea5 ("block: allow device to have both virt_boundary_mask and max segment size")
Tested-by: Geert Uytterhoeven <[email protected]>
Reported-by: Geert Uytterhoeven <[email protected]>
Closes: https://lore.kernel.org/linux-block/[email protected]/
Signed-off-by: Ming Lei <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

Author: Ming Lei

block/blk-settings.c

@@ -188,7 +188,10 @@ static int blk_validate_limits(struct queue_limits *lim)
 	 * bvec and lower layer bio splitting is supposed to handle the two
 	 * correctly.
 	 */
-	if (!lim->virt_boundary_mask) {
+	if (lim->virt_boundary_mask) {
+		if (!lim->max_segment_size)
+			lim->max_segment_size = UINT_MAX;
+	} else {
 		/*
 		 * The maximum segment size has an odd historic 64k default that
 		 * drivers probably should override.  Just like the I/O size we