scsi: use sector_div instead of do_div
authorArnd Bergmann <arnd@arndb.de>
Fri, 20 Nov 2015 16:38:28 +0000 (17:38 +0100)
committerMartin K. Petersen <martin.petersen@oracle.com>
Thu, 26 Nov 2015 03:17:02 +0000 (22:17 -0500)
do_div is the wrong way to divide a sector_t, as it is less efficient
when sector_t is 32-bit wide. With the upcoming do_div optimizations,
the kernel starts warning about this:

drivers/scsi/scsi_debug.c: In function 'dif_store':
include/asm-generic/div64.h:207:28: warning: comparison of distinct pointer types lacks a cast

This changes the code to use sector_div instead, which always produces
optimal code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Hannes Reinicke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/scsi/scsi_debug.c

index dfcc45bb03b1f30e808e611a567c2f76cc734d3c..ec622ba9864acc793ae59961c5fb9b953d5e41c4 100644 (file)
@@ -678,7 +678,7 @@ static void *fake_store(unsigned long long lba)
 
 static struct sd_dif_tuple *dif_store(sector_t sector)
 {
-       sector = do_div(sector, sdebug_store_sectors);
+       sector = sector_div(sector, sdebug_store_sectors);
 
        return dif_storep + sector;
 }
@@ -2780,7 +2780,7 @@ static unsigned long lba_to_map_index(sector_t lba)
                lba += scsi_debug_unmap_granularity -
                        scsi_debug_unmap_alignment;
        }
-       do_div(lba, scsi_debug_unmap_granularity);
+       sector_div(lba, scsi_debug_unmap_granularity);
 
        return lba;
 }