Re: [PATCH RFC v7 11/12] smartpqi: enable host tagset

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Hannes,

  static struct pqi_io_request *pqi_alloc_io_request(
-	struct pqi_ctrl_info *ctrl_info)
+	struct pqi_ctrl_info *ctrl_info, struct scsi_cmnd *scmd)
  {
  	struct pqi_io_request *io_request;
+	unsigned int limit = PQI_RESERVED_IO_SLOTS;
  	u16 i = ctrl_info->next_io_request_slot;	/* benignly racy */
- while (1) {
+	if (scmd) {
+		u32 blk_tag = blk_mq_unique_tag(scmd->request);
+
+		i = blk_mq_unique_tag_to_tag(blk_tag) + limit;
  		io_request = &ctrl_info->io_request_pool[i];

This looks ok

-		if (atomic_inc_return(&io_request->refcount) == 1)
-			break;
-		atomic_dec(&io_request->refcount);
-		i = (i + 1) % ctrl_info->max_io_slots;
+		if (WARN_ON(atomic_inc_return(&io_request->refcount) > 1)) {
+			atomic_dec(&io_request->refcount);
+			return NULL;
+		}
+	} else {
+		while (1) {
+			io_request = &ctrl_info->io_request_pool[i];
+			if (atomic_inc_return(&io_request->refcount) == 1)
+				break;
+			atomic_dec(&io_request->refcount);
+			i = (i + 1) % limit;

To me, the range we use here looks incorrect. I would assume we should restrict range to [max_io_slots - PQI_RESERVED_IO_SLOTS, max_io_slots).

But then your reserved commands support would solve that.

+		}
  	}

Thanks,
John



[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [SCSI Target Devel]     [Linux SCSI Target Infrastructure]     [Kernel Newbies]     [IDE]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux ATA RAID]     [Linux IIO]     [Samba]     [Device Mapper]

  Powered by Linux