[v2,4/4] block/scsi_ioctl.c: use queue_logical_sector_size() in max_sectors_bytes()

Commit Message

Tom Yan Sept. 6, 2020, 7:40 a.m. UTC

Programatically speaking it may not be necessary for us to clamp
max_sectors to USHRT_MAX here, but since such clamping is used in
BLKSECTGET, it's probably a good idea to have it here too, so that
what the function returns is consistent to what the ioctl reports.

Alternatively we can clamp (max_sectors * logical_block_size) to
INT_MAX instead, or maybe even not clamping it at all.

P.S. sg_reserved_size is initially set to INT_MAX by
blk_mq_init_allocated_queue().

Signed-off-by: Tom Yan <[e-mail]>
---
 block/scsi_ioctl.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

Patch

diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index ef722f04f88a..ae6aae40a8b6 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -73,10 +73,11 @@  static int sg_set_timeout(struct request_queue *q, int __user *p)
 static int max_sectors_bytes(struct request_queue *q)
 {
 	unsigned int max_sectors = queue_max_sectors(q);
+	unsigned int logical_block_size = queue_logical_block_size(q);
 
-	max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
+	max_sectors = min_t(unsigned int, max_sectors, USHRT_MAX);
 
-	return max_sectors << 9;
+	return max_sectors * logical_block_size;
 }
 
 static int sg_get_reserved_size(struct request_queue *q, int __user *p)