| Message ID | 1458563249-91200-1-git-send-email-hare@suse.de (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
On Mon, Mar 21, 2016 at 01:27:29PM +0100, Hannes Reinecke wrote: > in sd_read_capacity() the sdkp->capacity field changes its meaning: > after the call to read_capacity_XX() it carries the _unscaled_ values, > making the comparison between the original value and the new value > always false for drives with a sector size != 512. > So introduce a 'new_capacity' carrying the new, scaled, capacity. While this fixes a bug and adds a comment to clarify things I think the whole function is still a mess. And the way how your first calculate new_capacity but then keep the duplicated scaling on sdkp->capacity a littler later isn't really helpful either. Is there any chance to rewrite it so that the unscaled capacity has its own local variable, and sdkp->capacity is always either the correct old or new capacity? -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 5a5457a..fbb8daa 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -2312,8 +2312,13 @@ got_data: } blk_queue_logical_block_size(sdp->request_queue, sector_size); + /* + * Note: up to this point sdkp->capacity carries the + * _unscaled_ capacity (cf the scaling after this block). + */ { char cap_str_2[10], cap_str_10[10]; + size_t new_capacity = sdkp->capacity >> (ilog2(sector_size) - 9); string_get_size(sdkp->capacity, sector_size, STRING_UNITS_2, cap_str_2, sizeof(cap_str_2)); @@ -2321,7 +2326,7 @@ got_data: STRING_UNITS_10, cap_str_10, sizeof(cap_str_10)); - if (sdkp->first_scan || old_capacity != sdkp->capacity) { + if (sdkp->first_scan || old_capacity != new_capacity) { sd_printk(KERN_NOTICE, sdkp, "%llu %d-byte logical blocks: (%s/%s)\n", (unsigned long long)sdkp->capacity,
in sd_read_capacity() the sdkp->capacity field changes its meaning: after the call to read_capacity_XX() it carries the _unscaled_ values, making the comparison between the original value and the new value always false for drives with a sector size != 512. So introduce a 'new_capacity' carrying the new, scaled, capacity. Signed-off-by: Hannes Reinecke <hare@suse.de> --- drivers/scsi/sd.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)