path: root/drivers/ide/ide-io.c

/*
 *	IDE I/O functions
 *
 *	Basic PIO and command management functionality.
 *
 * This code was split off from ide.c. See ide.c for history and original
 * copyrights.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2, or (at your option) any
 * later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * For the avoidance of doubt the "preferred form" of this code is one which
 * is in an open non patent encumbered format. Where cryptographic key signing
 * forms part of the process of creating an executable the information
 * including keys needed to generate an equivalently functional executable
 * are deemed to be part of the source code.
 */
 
 
#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/major.h>
#include <linux/errno.h>
#include <linux/genhd.h>
#include <linux/blkpg.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/ide.h>
#include <linux/completion.h>
#include <linux/reboot.h>
#include <linux/cdrom.h>
#include <linux/seq_file.h>
#include <linux/device.h>
#include <linux/kmod.h>
#include <linux/scatterlist.h>
#include <linux/bitops.h>

#include <asm/byteorder.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <asm/io.h>

int ide_end_rq(ide_drive_t *drive, struct request *rq, int error,
	       unsigned int nr_bytes)
{
	/*
	 * decide whether to reenable DMA -- 3 is a random magic for now,
	 * if we DMA timeout more than 3 times, just stay in PIO
	 */
	if ((drive->dev_flags & IDE_DFLAG_DMA_PIO_RETRY) &&
	    drive->retry_pio <= 3) {
		drive->dev_flags &= ~IDE_DFLAG_DMA_PIO_RETRY;
		ide_dma_on(drive);
	}

	return blk_end_request(rq, error, nr_bytes);
}
EXPORT_SYMBOL_GPL(ide_end_rq);

void ide_complete_cmd(ide_drive_t *drive, struct ide_cmd *cmd, u8 stat, u8 err)
{
	const struct ide_tp_ops *tp_ops = drive->hwif->tp_ops;
	struct ide_taskfile *tf = &cmd->tf;
	struct request *rq = cmd->rq;
	u8 tf_cmd = tf->command;

	tf->error = err;
	tf->status = stat;

	if (cmd->ftf_flags & IDE_FTFLAG_IN_DATA) {
		u8 data[2];

		tp_ops->input_data(drive, cmd, data, 2);

		cmd->tf.data  = data[0];
		cmd->hob.data = data[1];
	}

	ide_tf_readback(drive, cmd);

	if ((cmd->tf_flags & IDE_TFLAG_CUSTOM_HANDLER) &&
	    tf_cmd == ATA_CMD_IDLEIMMEDIATE) {
		if (tf->lbal != 0xc4) {
			printk(KERN_ERR "%s: head unload failed!\n",
			       drive->name);
			ide_tf_dump(drive->name, cmd);
		} else
			drive->dev_flags |= IDE_DFLAG_PARKED;
	}

	if (rq && rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
		struct ide_cmd *orig_cmd = rq->special;

		if (cmd->tf_flags & IDE_TFLAG_DYN)
			kfree(orig_cmd);
		else
			memcpy(orig_cmd, cmd, sizeof(*cmd));
	}
}

/* obsolete, blk_rq_bytes() should be used instead */
unsigned int ide_rq_bytes(struct request *rq)
{
	if (blk_pc_request(rq))
		return blk_rq_bytes(rq);
	else
		return blk_rq_cur_sectors(rq) << 9;
}
EXPORT_SYMBOL_GPL(ide_rq_bytes);

int ide_complete_rq(ide_drive_t *drive, int error, unsigned int nr_bytes)
{
	ide_hwif_t *hwif = drive->hwif;
	struct request *rq = hwif->rq;
	int rc;

	/*
	 * if failfast is set on a request, override number of sectors
	 * and complete the whole request right now
	 */
	if (blk_noretry_request(rq) && error <= 0)
		nr_bytes = blk_rq_sectors(rq) << 9;

	rc = ide_end_rq(drive, rq, error, nr_bytes);
	if (rc == 0)
		hwif->rq = NULL;

	return rc;
}
EXPORT_SYMBOL(ide_complete_rq);

void ide_kill_rq(ide_drive_t *drive, struct request *rq)
{
	u8 drv_req = blk_special_request(rq) && rq->rq_disk;
	u8 media = drive->media;

	drive->failed_pc = NULL;

	if ((media == ide_floppy || media == ide_tape) && drv_req) {
		rq->errors = 0;
		ide_complete_rq(drive, 0, blk_rq_bytes(rq));
	} else {
		if (media == ide_tape)
			rq->errors = IDE_DRV_ERROR_GENERAL;
		else if (blk_fs_request(rq) == 0 && rq->errors == 0)
			rq->errors = -EIO;
		ide_complete_rq(drive, -EIO, ide_rq_bytes(rq));
	}
}

static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
{
	tf->nsect   = drive->sect;
	tf->lbal