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[SCSI] aha152x: Fix check_condition code-path

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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: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This commit is contained in:
Boaz Harrosh 2007-07-29 22:27:06 +03:00 committed by James Bottomley
parent 66acdb0309
commit 45333ffa6f
1 changed files with 27 additions and 28 deletions
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55
drivers/scsi/aha152x.c
View File

@ -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) {
SCpnt->SCp.ptr = NULL;
SCpnt->SCp.this_residual = 0;
SCpnt->resid = 0;
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;
@ -1601,10 +1603,7 @@ 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);
DO_LOCK(flags);