[PATCH] cciss: Fix warnings (and bug on 1TB discs)

Matthew Wilcox
2006-10-20T03:23:39Z

CCISS was producing warnings about shifts being greater than the size
of the type and pointers being of incompatible type. Turns out this
is because it's calling do_div on a 32-bit quantity. Upon further
investigation, the sector_t total_size is being assigned to an int,
and then we're calling do_div on that int. Obviously, sector_div is
called for here, and I took the chance to refactor the code a little.

diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index dcccaf2..bc66026 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -1923,7 +1923,6 @@ static void cciss_geometry_inquiry(int c
{
int return_code;
unsigned long t;
- unsigned long rem;

memset(inq_buff, 0, sizeof(InquiryData_struct));
if (withirq)
@@ -1939,26 +1938,23 @@ static void cciss_geometry_inquiry(int c
printk(KERN_WARNING
"cciss: reading geometry failed, volume "
"does not support reading geometry\n");
- drv->block_size = block_size;
- drv->nr_blocks = total_size;
drv->heads = 255;
drv->sectors = 32; // Sectors per track
- t = drv->heads * drv->sectors;
- drv->cylinders = total_size;
- rem = do_div(drv->cylinders, t);
} else {
- drv->block_size = block_size;
- drv->nr_blocks = total_size;
drv->heads = inq_buff->data_byte[6];
drv->sectors = inq_buff->data_byte[7];
drv->cylinders = (inq_buff->data_byte[4] & 0xff) << 8;
drv->cylinders += inq_buff->data_byte[5];
drv->raid_level = inq_buff->data_byte[8];
- t = drv->heads * drv->sectors;
- if (t > 1) {
- drv->cylinders = total_size;
- rem = do_div(drv->cylinders, t);
- }
+ }
+ drv->block_size = block_size;
+ drv->nr_blocks = total_size;
+ t = drv->heads * drv->sectors;
+ if (t > 1) {
+ unsigned rem = sector_div(total_size, t);
+ if (rem)
+ total_size++;
+ drv->cylinders = total_size;
}
} else { /* Get geometry failed */
printk(KERN_WARNING "cciss: reading geometry failed\n");