Commit eb6a61bb authored by Tejun Heo's avatar Tejun Heo Committed by Jens Axboe

ide-atapi,tape,floppy: allow ->pc_callback() to change rq->data_len

Impact: allow residual count implementation in ->pc_callback()

rq->data_len has two duties - carrying the number of input bytes on
issue and carrying residual count back to the issuer on completion.
ide-atapi completion callback ->pc_callback() is the right place to do
this but currently ide-atapi depends on rq->data_len carrying the
original request size after calling ->pc_callback() to complete the pc
request.

This patch makes ide_pc_intr(), ide_tape_issue_pc() and
ide_floppy_issue_pc() cache length to complete before calling
->pc_callback() so that it can modify rq->data_len as necessary.

Note: As using rq->data_len for two purposes can make cases like this
      incorrect in subtle ways, future changes will introduce separate
      field for residual count.
Signed-off-by: 's avatarTejun Heo <tj@kernel.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
parent 08f370f0
......@@ -409,6 +409,16 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive)
if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0)
dsc = 1;
/*
* ->pc_callback() might change rq->data_len for
* residual count, cache total length.
*/
if (!blk_special_request(rq) &&
(drive->media == ide_tape && !rq->bio))
done = ide_rq_bytes(rq); /* FIXME */
else
done = blk_rq_bytes(rq);
/* Command finished - Call the callback function */
uptodate = drive->pc_callback(drive, dsc);
......@@ -417,7 +427,6 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive)
if (blk_special_request(rq)) {
rq->errors = 0;
done = blk_rq_bytes(rq);
error = 0;
} else {
......@@ -426,11 +435,6 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive)
rq->errors = -EIO;
}
if (drive->media == ide_tape && !rq->bio)
done = ide_rq_bytes(rq); /* FIXME */
else
done = blk_rq_bytes(rq);
error = uptodate ? 0 : -EIO;
}
......
......@@ -134,14 +134,17 @@ static ide_startstop_t ide_floppy_issue_pc(ide_drive_t *drive,
drive->pc = pc;
if (pc->retries > IDEFLOPPY_MAX_PC_RETRIES) {
unsigned int done = blk_rq_bytes(drive->hwif->rq);
if (!(pc->flags & PC_FLAG_SUPPRESS_ERROR))
ide_floppy_report_error(floppy, pc);
/* Giving up */
pc->error = IDE_DRV_ERROR_GENERAL;
drive->failed_pc = NULL;
drive->pc_callback(drive, 0);
ide_complete_rq(drive, -EIO, blk_rq_bytes(drive->hwif->rq));
ide_complete_rq(drive, -EIO, done);
return ide_stopped;
}
......
......@@ -622,6 +622,8 @@ static ide_startstop_t ide_tape_issue_pc(ide_drive_t *drive,
if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
(pc->flags & PC_FLAG_ABORT)) {
unsigned int done = blk_rq_bytes(drive->hwif->rq);
/*
* We will "abort" retrying a packet command in case legitimate
* error code was received (crossing a filemark, or end of the
......@@ -641,9 +643,10 @@ static ide_startstop_t ide_tape_issue_pc(ide_drive_t *drive,
/* Giving up */
pc->error = IDE_DRV_ERROR_GENERAL;
}
drive->failed_pc = NULL;
drive->pc_callback(drive, 0);
ide_complete_rq(drive, -EIO, blk_rq_bytes(drive->hwif->rq));
ide_complete_rq(drive, -EIO, done);
return ide_stopped;
}
debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]);
......
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