ide: add helpers for preparing sense requests
This is in preparation of removing the queueing of a sense request out
of the IRQ handler path.
Use struct request_sense as a general sense buffer for all ATAPI
devices ide-{floppy,tape,cd}.
tj: * blk_get_request(__GFP_WAIT) can't be called from do_request() as
it can cause deadlock. Converted to use inline struct request
and blk_rq_init().
* Added xfer / cdb len selection depending on device type.
* All sense prep logics folded into ide_prep_sense() which never
fails.
* hwif->rq clearing and sense_rq used handling moved into
ide_queue_sense_rq().
* blk_rq_map_kern() conversion is moved to later patch.
CC: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
CC: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c
index 2894577..c6e0348 100644
--- a/drivers/ide/ide-atapi.c
+++ b/drivers/ide/ide-atapi.c
@@ -191,6 +191,67 @@
}
EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd);
+void ide_prep_sense(ide_drive_t *drive, struct request *rq)
+{
+ struct request_sense *sense = &drive->sense_data;
+ struct request *sense_rq = &drive->sense_rq;
+ unsigned int cmd_len, sense_len;
+
+ debug_log("%s: enter\n", __func__);
+
+ switch (drive->media) {
+ case ide_floppy:
+ cmd_len = 255;
+ sense_len = 18;
+ break;
+ case ide_tape:
+ cmd_len = 20;
+ sense_len = 20;
+ break;
+ default:
+ cmd_len = 18;
+ sense_len = 18;
+ }
+
+ BUG_ON(sense_len > sizeof(*sense));
+
+ if (blk_sense_request(rq) || drive->sense_rq_armed)
+ return;
+
+ memset(sense, 0, sizeof(*sense));
+
+ blk_rq_init(rq->q, sense_rq);
+ sense_rq->rq_disk = rq->rq_disk;
+
+ sense_rq->data = sense;
+ sense_rq->cmd[0] = GPCMD_REQUEST_SENSE;
+ sense_rq->cmd[4] = cmd_len;
+ sense_rq->data_len = sense_len;
+
+ sense_rq->cmd_type = REQ_TYPE_SENSE;
+ sense_rq->cmd_flags |= REQ_PREEMPT;
+
+ if (drive->media == ide_tape)
+ sense_rq->cmd[13] = REQ_IDETAPE_PC1;
+
+ drive->sense_rq_armed = true;
+}
+EXPORT_SYMBOL_GPL(ide_prep_sense);
+
+void ide_queue_sense_rq(ide_drive_t *drive, void *special)
+{
+ BUG_ON(!drive->sense_rq_armed);
+
+ drive->sense_rq.special = special;
+ drive->sense_rq_armed = false;
+
+ drive->hwif->rq = NULL;
+
+ elv_add_request(drive->queue, &drive->sense_rq,
+ ELEVATOR_INSERT_FRONT, 0);
+}
+EXPORT_SYMBOL_GPL(ide_queue_sense_rq);
+
/*
* Called when an error was detected during the last packet command.
* We queue a request sense packet command in the head of the request list.