Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 45333ffa authored by Boaz Harrosh's avatar Boaz Harrosh Committed by James Bottomley
Browse files

[SCSI] aha152x: Fix check_condition code-path 



check_condition code-path was similar but more
complicated to Reset. It went like this:

  1. extra space was allocated at aha152x_scdata for mirroring
    scsi_cmnd members.
  2. At aha152x_internal_queue() every not check_condition
    (REQUEST_SENSE) command was copied to above members in
    case of error.
  3. At busfree_run() in the DONE_CS phase if a Status of
    SAM_STAT_CHECK_CONDITION was detected. The command was
    re-queued Internally using aha152x_internal_queue(,,check_condition,)
    The old command members are over written with the
    REQUEST_SENSE info.
  4. At busfree_run() in the DONE_CS phase again. If it is a
    check_condition command, info was restored from mirror
    made at first call to aha152x_internal_queue() (see 2)
    and the command is completed.

What I did is:

  1. Allocate less space in aha152x_scdata only for the 16-byte
    original command. (which is actually not needed by scsi-ml
    anymore at this stage. But this is to much knowledge of scsi-ml)
  2. If Status == SAM_STAT_CHECK_CONDITION, then like before
     re-queue a REQUEST_SENSE command. But only now save original
     command members. (Less of them)
  3. In aha152x_internal_queue(), just like for Reset, use the
    check_condition hint to set differently the working members.
    execute the command.
  4. At busfree_run() in the DONE_CS phase again. restore needed
     members.

While at it. This patch fixes a BUG. Old code when sending
a REQUEST_SENSE for a failed command. Would than return with
cmd->resid == 0 which was the status of the REQUEST_SENSE.
The failing command resid was lost. And when would resid
be interesting if not on a failing command?

Signed-off-by: default avatarBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
parent 66acdb03

drivers/scsi/aha152x.c

+27 −28
Original line number Diff line number Diff line
@@ -552,14 +552,11 @@ struct aha152x_hostdata { 
struct aha152x_scdata {

	Scsi_Cmnd *next;	/* next sc in queue */

	struct completion *done;/* semaphore to block on */

	unsigned char cmd_len;

	unsigned char cmnd[MAX_COMMAND_SIZE];

	unsigned short use_sg;

	unsigned request_bufflen;

	void *request_buffer;

	unsigned char aha_orig_cmd_len;

	unsigned char aha_orig_cmnd[MAX_COMMAND_SIZE];

	int aha_orig_resid;

};





/* access macros for hostdata */



#define HOSTDATA(shpnt)		((struct aha152x_hostdata *) &shpnt->hostdata)
@@ -997,20 +994,11 @@ static int aha152x_internal_queue(Scsi_Cmnd *SCpnt, struct completion *complete, 
			return FAILED;

		}

	} else {

		struct aha152x_scdata *sc;



		SCpnt->host_scribble = kmalloc(sizeof(struct aha152x_scdata), GFP_ATOMIC);

		if(SCpnt->host_scribble==0) {

			printk(ERR_LEAD "allocation failed\n", CMDINFO(SCpnt));

			return FAILED;

		}



		sc = SCDATA(SCpnt);

		memcpy(sc->cmnd, SCpnt->cmnd, sizeof(sc->cmnd));

		sc->request_buffer  = SCpnt->request_buffer;

		sc->request_bufflen = SCpnt->request_bufflen;

		sc->use_sg          = SCpnt->use_sg;

		sc->cmd_len         = SCpnt->cmd_len;

	}



	SCNEXT(SCpnt)		= NULL;
@@ -1023,10 +1011,16 @@ static int aha152x_internal_queue(Scsi_Cmnd *SCpnt, struct completion *complete, 
	   SCp.buffers_residual : left buffers in list

	   SCp.phase            : current state of the command */



	if(phase & resetting) {

	if (phase & (check_condition|resetting)) {

		if (phase & check_condition) {

			SCpnt->SCp.ptr           = SCpnt->sense_buffer;

			SCpnt->SCp.this_residual = sizeof(SCpnt->sense_buffer);

			SCpnt->resid             = sizeof(SCpnt->sense_buffer);

		} else {

			SCpnt->SCp.ptr           = NULL;

			SCpnt->SCp.this_residual = 0;

			SCpnt->resid             = 0;

		}

		SCpnt->SCp.buffer           = NULL;

		SCpnt->SCp.buffers_residual = 0;

	} else {
@@ -1568,11 +1562,9 @@ static void busfree_run(struct Scsi_Host *shpnt) 
#endif



			/* restore old command */

			memcpy(cmd->cmnd, sc->cmnd, sizeof(sc->cmnd));

			cmd->request_buffer  = sc->request_buffer;

			cmd->request_bufflen = sc->request_bufflen;

			cmd->use_sg          = sc->use_sg;

			cmd->cmd_len         = sc->cmd_len;

			memcpy(cmd->cmnd, sc->aha_orig_cmnd, sizeof(cmd->cmnd));

			cmd->cmd_len = sc->aha_orig_cmd_len;

			cmd->resid = sc->aha_orig_resid;



			cmd->SCp.Status = SAM_STAT_CHECK_CONDITION;
@@ -1588,12 +1580,22 @@ static void busfree_run(struct Scsi_Host *shpnt) 
#endif



			if(!(DONE_SC->SCp.phase & not_issued)) {

				struct aha152x_scdata *sc;

				Scsi_Cmnd *ptr = DONE_SC;

				DONE_SC=NULL;

#if 0

				DPRINTK(debug_eh, ERR_LEAD "requesting sense\n", CMDINFO(ptr));

#endif



				/* save old command */

				sc = SCDATA(ptr);

				/* It was allocated in aha152x_internal_queue? */

				BUG_ON(!sc);

				memcpy(sc->aha_orig_cmnd, ptr->cmnd,

				                            sizeof(ptr->cmnd));

				sc->aha_orig_cmd_len = ptr->cmd_len;

				sc->aha_orig_resid = ptr->resid;



				ptr->cmnd[0]         = REQUEST_SENSE;

				ptr->cmnd[1]         = 0;

				ptr->cmnd[2]         = 0;
@@ -1601,9 +1603,6 @@ static void busfree_run(struct Scsi_Host *shpnt) 
				ptr->cmnd[4]         = sizeof(ptr->sense_buffer);

				ptr->cmnd[5]         = 0;

				ptr->cmd_len         = 6;

				ptr->use_sg          = 0; 

				ptr->request_buffer  = ptr->sense_buffer;

				ptr->request_bufflen = sizeof(ptr->sense_buffer);



				DO_UNLOCK(flags);

				aha152x_internal_queue(ptr, NULL, check_condition, ptr->scsi_done);