Commit a1df5169 authored by Borislav Petkov's avatar Borislav Petkov Committed by Tejun Heo
Browse files

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: default avatarBorislav Petkov <petkovbb@gmail.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent cbfd082a

drivers/ide/ide-atapi.c

+61 −0
Original line number Diff line number Diff line
@@ -191,6 +191,67 @@ void ide_create_request_sense_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc) 
}

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.

include/linux/ide.h

+11 −0
Original line number Diff line number Diff line
@@ -26,6 +26,9 @@ 
#include <asm/io.h>

#include <asm/mutex.h>



/* for request_sense */

#include <linux/cdrom.h>



#if defined(CONFIG_CRIS) || defined(CONFIG_FRV) || defined(CONFIG_MN10300)

# define SUPPORT_VLB_SYNC 0

#else
@@ -602,6 +605,11 @@ struct ide_drive_s { 


	struct ide_atapi_pc request_sense_pc;

	struct request request_sense_rq;



	/* current sense rq and buffer */

	bool sense_rq_armed;

	struct request sense_rq;

	struct request_sense sense_data;

};



typedef struct ide_drive_s ide_drive_t;
@@ -1175,6 +1183,9 @@ int ide_set_media_lock(ide_drive_t *, struct gendisk *, int); 
void ide_create_request_sense_cmd(ide_drive_t *, struct ide_atapi_pc *);

void ide_retry_pc(ide_drive_t *, struct gendisk *);



void ide_prep_sense(ide_drive_t *drive, struct request *rq);

void ide_queue_sense_rq(ide_drive_t *drive, void *special);



int ide_cd_expiry(ide_drive_t *);



int ide_cd_get_xferlen(struct request *);

CRA Git | Maintained and supported by SUSTech CRA and CCSE