diff options
Diffstat (limited to 'drivers/ide/ide-io.c')
| -rw-r--r-- | drivers/ide/ide-io.c | 1539 |
1 files changed, 1539 insertions, 0 deletions
diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c new file mode 100644 index 0000000..81f99bd --- /dev/null +++ b/drivers/ide/ide-io.c @@ -0,0 +1,1539 @@ +/* + * 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/hdreg.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> + +static int __ide_end_request(ide_drive_t *drive, struct request *rq, + int uptodate, unsigned int nr_bytes, int dequeue) +{ + int ret = 1; + int error = 0; + + if (uptodate <= 0) + error = uptodate ? uptodate : -EIO; + + /* + * if failfast is set on a request, override number of sectors and + * complete the whole request right now + */ + if (blk_noretry_request(rq) && error) + nr_bytes = rq->hard_nr_sectors << 9; + + if (!blk_fs_request(rq) && error && !rq->errors) + rq->errors = -EIO; + + /* + * 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); + } + + if (!__blk_end_request(rq, error, nr_bytes)) { + if (dequeue) + HWGROUP(drive)->rq = NULL; + ret = 0; + } + + return ret; +} + +/** + * ide_end_request - complete an IDE I/O + * @drive: IDE device for the I/O + * @uptodate: + * @nr_sectors: number of sectors completed + * + * This is our end_request wrapper function. We complete the I/O + * update random number input and dequeue the request, which if + * it was tagged may be out of order. + */ + +int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors) +{ + unsigned int nr_bytes = nr_sectors << 9; + struct request *rq; + unsigned long flags; + int ret = 1; + + /* + * room for locking improvements here, the calls below don't + * need the queue lock held at all + */ + spin_lock_irqsave(&ide_lock, flags); + rq = HWGROUP(drive)->rq; + + if (!nr_bytes) { + if (blk_pc_request(rq)) + nr_bytes = rq->data_len; + else + nr_bytes = rq->hard_cur_sectors << 9; + } + + ret = __ide_end_request(drive, rq, uptodate, nr_bytes, 1); + + spin_unlock_irqrestore(&ide_lock, flags); + return ret; +} +EXPORT_SYMBOL(ide_end_request); + +static void ide_complete_power_step(ide_drive_t *drive, struct request *rq) +{ + struct request_pm_state *pm = rq->data; + +#ifdef DEBUG_PM + printk(KERN_INFO "%s: complete_power_step(step: %d)\n", + drive->name, pm->pm_step); +#endif + if (drive->media != ide_disk) + return; + + switch (pm->pm_step) { + case IDE_PM_FLUSH_CACHE: /* Suspend step 1 (flush cache) */ + if (pm->pm_state == PM_EVENT_FREEZE) + pm->pm_step = IDE_PM_COMPLETED; + else + pm->pm_step = IDE_PM_STANDBY; + break; + case IDE_PM_STANDBY: /* Suspend step 2 (standby) */ + pm->pm_step = IDE_PM_COMPLETED; + break; + case IDE_PM_RESTORE_PIO: /* Resume step 1 (restore PIO) */ + pm->pm_step = IDE_PM_IDLE; + break; + case IDE_PM_IDLE: /* Resume step 2 (idle)*/ + pm->pm_step = IDE_PM_RESTORE_DMA; + break; + } +} + +static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq) +{ + struct request_pm_state *pm = rq->data; + ide_task_t *args = rq->special; + + memset(args, 0, sizeof(*args)); + + switch (pm->pm_step) { + case IDE_PM_FLUSH_CACHE: /* Suspend step 1 (flush cache) */ + if (drive->media != ide_disk) + break; + /* Not supported? Switch to next step now. */ + if (ata_id_flush_enabled(drive->id) == 0 || + (drive->dev_flags & IDE_DFLAG_WCACHE) == 0) { + ide_complete_power_step(drive, rq); + return ide_stopped; + } + if (ata_id_flush_ext_enabled(drive->id)) + args->tf.command = ATA_CMD_FLUSH_EXT; + else + args->tf.command = ATA_CMD_FLUSH; + goto out_do_tf; + case IDE_PM_STANDBY: /* Suspend step 2 (standby) */ + args->tf.command = ATA_CMD_STANDBYNOW1; + goto out_do_tf; + case IDE_PM_RESTORE_PIO: /* Resume step 1 (restore PIO) */ + ide_set_max_pio(drive); + /* + * skip IDE_PM_IDLE for ATAPI devices + */ + if (drive->media != ide_disk) + pm->pm_step = IDE_PM_RESTORE_DMA; + else + ide_complete_power_step(drive, rq); + return ide_stopped; + case IDE_PM_IDLE: /* Resume step 2 (idle) */ + args->tf.command = ATA_CMD_IDLEIMMEDIATE; + goto out_do_tf; + case IDE_PM_RESTORE_DMA: /* Resume step 3 (restore DMA) */ + /* + * Right now, all we do is call ide_set_dma(drive), + * we could be smarter and check for current xfer_speed + * in struct drive etc... + */ + if (drive->hwif->dma_ops == NULL) + break; + /* + * TODO: respect IDE_DFLAG_USING_DMA + */ + ide_set_dma(drive); + break; + } + + pm->pm_step = IDE_PM_COMPLETED; + return ide_stopped; + +out_do_tf: + args->tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE; + args->data_phase = TASKFILE_NO_DATA; + return do_rw_taskfile(drive, args); +} + +/** + * ide_end_dequeued_request - complete an IDE I/O + * @drive: IDE device for the I/O + * @uptodate: + * @nr_sectors: number of sectors completed + * + * Complete an I/O that is no longer on the request queue. This + * typically occurs when we pull the request and issue a REQUEST_SENSE. + * We must still finish the old request but we must not tamper with the + * queue in the meantime. + * + * NOTE: This path does not handle barrier, but barrier is not supported + * on ide-cd anyway. + */ + +int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq, + int uptodate, int nr_sectors) +{ + unsigned long flags; + int ret; + + spin_lock_irqsave(&ide_lock, flags); + BUG_ON(!blk_rq_started(rq)); + ret = __ide_end_request(drive, rq, uptodate, nr_sectors << 9, 0); + spin_unlock_irqrestore(&ide_lock, flags); + + return ret; +} +EXPORT_SYMBOL_GPL(ide_end_dequeued_request); + + +/** + * ide_complete_pm_request - end the current Power Management request + * @drive: target drive + * @rq: request + * + * This function cleans up the current PM request and stops the queue + * if necessary. + */ +static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq) +{ + unsigned long flags; + +#ifdef DEBUG_PM + printk("%s: completing PM request, %s\n", drive->name, + blk_pm_suspend_request(rq) ? "suspend" : "resume"); +#endif + spin_lock_irqsave(&ide_lock, flags); + if (blk_pm_suspend_request(rq)) { + blk_stop_queue(drive->queue); + } else { + drive->dev_flags &= ~IDE_DFLAG_BLOCKED; + blk_start_queue(drive->queue); + } + HWGROUP(drive)->rq = NULL; + if (__blk_end_request(rq, 0, 0)) + BUG(); + spin_unlock_irqrestore(&ide_lock, flags); +} + +/** + * ide_end_drive_cmd - end an explicit drive command + * @drive: command + * @stat: status bits + * @err: error bits + * + * Clean up after success/failure of an explicit drive command. + * These get thrown onto the queue so they are synchronized with + * real I/O operations on the drive. + * + * In LBA48 mode we have to read the register set twice to get + * all the extra information out. + */ + +void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err) +{ + unsigned long flags; + struct request *rq; + + spin_lock_irqsave(&ide_lock, flags); + rq = HWGROUP(drive)->rq; + spin_unlock_irqrestore(&ide_lock, flags); + + if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { + ide_task_t *task = (ide_task_t *)rq->special; + + if (rq->errors == 0) + rq->errors = !OK_STAT(stat, ATA_DRDY, BAD_STAT); + + if (task) { + struct ide_taskfile *tf = &task->tf; + + tf->error = err; + tf->status = stat; + + drive->hwif->tp_ops->tf_read(drive, task); + + if (task->tf_flags & IDE_TFLAG_DYN) + kfree(task); + } + } else if (blk_pm_request(rq)) { + struct request_pm_state *pm = rq->data; + + ide_complete_power_step(drive, rq); + if (pm->pm_step == IDE_PM_COMPLETED) + ide_complete_pm_request(drive, rq); + return; + } + + spin_lock_irqsave(&ide_lock, flags); + HWGROUP(drive)->rq = NULL; + rq->errors = err; + if (unlikely(__blk_end_request(rq, (rq->errors ? -EIO : 0), + blk_rq_bytes(rq)))) + BUG(); + spin_unlock_irqrestore(&ide_lock, flags); +} + +EXPORT_SYMBOL(ide_end_drive_cmd); + +static void ide_kill_rq(ide_drive_t *drive, struct request *rq) +{ + if (rq->rq_disk) { + ide_driver_t *drv; + + drv = *(ide_driver_t **)rq->rq_disk->private_data; + drv->end_request(drive, 0, 0); + } else + ide_end_request(drive, 0, 0); +} + +static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) +{ + ide_hwif_t *hwif = drive->hwif; + + if ((stat & ATA_BUSY) || + ((stat & ATA_DF) && (drive->dev_flags & IDE_DFLAG_NOWERR) == 0)) { + /* other bits are useless when BUSY */ + rq->errors |= ERROR_RESET; + } else if (stat & ATA_ERR) { + /* err has different meaning on cdrom and tape */ + if (err == ATA_ABORTED) { + if ((drive->dev_flags & IDE_DFLAG_LBA) && + /* some newer drives don't support ATA_CMD_INIT_DEV_PARAMS */ + hwif->tp_ops->read_status(hwif) == ATA_CMD_INIT_DEV_PARAMS) + return ide_stopped; + } else if ((err & BAD_CRC) == BAD_CRC) { + /* UDMA crc error, just retry the operation */ + drive->crc_count++; + } else if (err & (ATA_BBK | ATA_UNC)) { + /* retries won't help these */ + rq->errors = ERROR_MAX; + } else if (err & ATA_TRK0NF) { + /* help it find track zero */ + rq->errors |= ERROR_RECAL; + } + } + + if ((stat & ATA_DRQ) && rq_data_dir(rq) == READ && + (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0) { + int nsect = drive->mult_count ? drive->mult_count : 1; + + ide_pad_transfer(drive, READ, nsect * SECTOR_SIZE); + } + + if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) { + ide_kill_rq(drive, rq); + return ide_stopped; + } + + if (hwif->tp_ops->read_status(hwif) & (ATA_BUSY | ATA_DRQ)) + rq->errors |= ERROR_RESET; + + if ((rq->errors & ERROR_RESET) == ERROR_RESET) { + ++rq->errors; + return ide_do_reset(drive); + } + + if ((rq->errors & ERROR_RECAL) == ERROR_RECAL) + drive->special.b.recalibrate = 1; + + ++rq->errors; + + return ide_stopped; +} + +static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) +{ + ide_hwif_t *hwif = drive->hwif; + + if ((stat & ATA_BUSY) || + ((stat & ATA_DF) && (drive->dev_flags & IDE_DFLAG_NOWERR) == 0)) { + /* other bits are useless when BUSY */ + rq->errors |= ERROR_RESET; + } else { + /* add decoding error stuff */ + } + + if (hwif->tp_ops->read_status(hwif) & (ATA_BUSY | ATA_DRQ)) + /* force an abort */ + hwif->tp_ops->exec_command(hwif, ATA_CMD_IDLEIMMEDIATE); + + if (rq->errors >= ERROR_MAX) { + ide_kill_rq(drive, rq); + } else { + if ((rq->errors & ERROR_RESET) == ERROR_RESET) { + ++rq->errors; + return ide_do_reset(drive); + } + ++rq->errors; + } + + return ide_stopped; +} + +ide_startstop_t +__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) +{ + if (drive->media == ide_disk) + return ide_ata_error(drive, rq, stat, err); + return ide_atapi_error(drive, rq, stat, err); +} + +EXPORT_SYMBOL_GPL(__ide_error); + +/** + * ide_error - handle an error on the IDE + * @drive: drive the error occurred on + * @msg: message to report + * @stat: status bits + * + * ide_error() takes action based on the error returned by the drive. + * For normal I/O that may well include retries. We deal with + * both new-style (taskfile) and old style command handling here. + * In the case of taskfile command handling there is work left to + * do + */ + +ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat) +{ + struct request *rq; + u8 err; + + err = ide_dump_status(drive, msg, stat); + + if ((rq = HWGROUP(drive)->rq) == NULL) + return ide_stopped; + + /* retry only "normal" I/O: */ + if (!blk_fs_request(rq)) { + rq->errors = 1; + ide_end_drive_cmd(drive, stat, err); + return ide_stopped; + } + + if (rq->rq_disk) { + ide_driver_t *drv; + + drv = *(ide_driver_t **)rq->rq_disk->private_data; + return drv->error(drive, rq, stat, err); + } else + return __ide_error(drive, rq, stat, err); +} + +EXPORT_SYMBOL_GPL(ide_error); + +static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf) +{ + tf->nsect = drive->sect; + tf->lbal = drive->sect; + tf->lbam = drive->cyl; + tf->lbah = drive->cyl >> 8; + tf->device = (drive->head - 1) | drive->select; + tf->command = ATA_CMD_INIT_DEV_PARAMS; +} + +static void ide_tf_set_restore_cmd(ide_drive_t *drive, struct ide_taskfile *tf) +{ + tf->nsect = drive->sect; + tf->command = ATA_CMD_RESTORE; +} + +static void ide_tf_set_setmult_cmd(ide_drive_t *drive, struct ide_taskfile *tf) +{ + tf->nsect = drive->mult_req; + tf->command = ATA_CMD_SET_MULTI; +} + +static ide_startstop_t ide_disk_special(ide_drive_t *drive) +{ + special_t *s = &drive->special; + ide_task_t args; + + memset(&args, 0, sizeof(ide_task_t)); + args.data_phase = TASKFILE_NO_DATA; + + if (s->b.set_geometry) { + s->b.set_geometry = 0; + ide_tf_set_specify_cmd(drive, &args.tf); + } else if (s->b.recalibrate) { + s->b.recalibrate = 0; + ide_tf_set_restore_cmd(drive, &args.tf); + } else if (s->b.set_multmode) { + s->b.set_multmode = 0; + ide_tf_set_setmult_cmd(drive, &args.tf); + } else if (s->all) { + int special = s->all; + s->all = 0; + printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special); + return ide_stopped; + } + + args.tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE | + IDE_TFLAG_CUSTOM_HANDLER; + + do_rw_taskfile(drive, &args); + + return ide_started; +} + +/** + * do_special - issue some special commands + * @drive: drive the command is for + * + * do_special() is used to issue ATA_CMD_INIT_DEV_PARAMS, + * ATA_CMD_RESTORE and ATA_CMD_SET_MULTI commands to a drive. + * + * It used to do much more, but has been scaled back. + */ + +static ide_startstop_t do_special (ide_drive_t *drive) +{ + special_t *s = &drive->special; + +#ifdef DEBUG + printk("%s: do_special: 0x%02x\n", drive->name, s->all); +#endif + if (drive->media == ide_disk) + return ide_disk_special(drive); + + s->all = 0; + drive->mult_req = 0; + return ide_stopped; +} + +void ide_map_sg(ide_drive_t *drive, struct request *rq) +{ + ide_hwif_t *hwif = drive->hwif; + struct scatterlist *sg = hwif->sg_table; + + if (hwif->sg_mapped) /* needed by ide-scsi */ + return; + + if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { + sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE); + hwif->sg_nents = 1; + } else if (!rq->bio) { + sg_init_one(sg, rq->data, rq->data_len); + hwif->sg_nents = 1; + } else { + hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg); + } +} + +EXPORT_SYMBOL_GPL(ide_map_sg); + +void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq) +{ + ide_hwif_t *hwif = drive->hwif; + + hwif->nsect = hwif->nleft = rq->nr_sectors; + hwif->cursg_ofs = 0; + hwif->cursg = NULL; +} + +EXPORT_SYMBOL_GPL(ide_init_sg_cmd); + +/** + * execute_drive_command - issue special drive command + * @drive: the drive to issue the command on + * @rq: the request structure holding the command + * + * execute_drive_cmd() issues a special drive command, usually + * initiated by ioctl() from the external hdparm program. The + * command can be a drive command, drive task or taskfile + * operation. Weirdly you can call it with NULL to wait for + * all commands to finish. Don't do this as that is due to change + */ + +static ide_startstop_t execute_drive_cmd (ide_drive_t *drive, + struct request *rq) +{ + ide_hwif_t *hwif = HWIF(drive); + ide_task_t *task = rq->special; + + if (task) { + hwif->data_phase = task->data_phase; + + switch (hwif->data_phase) { + case TASKFILE_MULTI_OUT: + case TASKFILE_OUT: + case TASKFILE_MULTI_IN: + case TASKFILE_IN: + ide_init_sg_cmd(drive, rq); + ide_map_sg(drive, rq); + default: + break; + } + + return do_rw_taskfile(drive, task); + } + + /* + * NULL is actually a valid way of waiting for + * all current requests to be flushed from the queue. + */ +#ifdef DEBUG + printk("%s: DRIVE_CMD (null)\n", drive->name); +#endif + ide_end_drive_cmd(drive, hwif->tp_ops->read_status(hwif), + ide_read_error(drive)); + + return ide_stopped; +} + +int ide_devset_execute(ide_drive_t *drive, const struct ide_devset *setting, + int arg) +{ + struct request_queue *q = drive->queue; + struct request *rq; + int ret = 0; + + if (!(setting->flags & DS_SYNC)) + return setting->set(drive, arg); + + rq = blk_get_request(q, READ, __GFP_WAIT); + rq->cmd_type = REQ_TYPE_SPECIAL; + rq->cmd_len = 5; + rq->cmd[0] = REQ_DEVSET_EXEC; + *(int *)&rq->cmd[1] = arg; + rq->special = setting->set; + + if (blk_execute_rq(q, NULL, rq, 0)) + ret = rq->errors; + blk_put_request(rq); + + return ret; +} +EXPORT_SYMBOL_GPL(ide_devset_execute); + +static ide_startstop_t ide_special_rq(ide_drive_t *drive, struct request *rq) +{ + u8 cmd = rq->cmd[0]; + + if (cmd == REQ_PARK_HEADS || cmd == REQ_UNPARK_HEADS) { + ide_task_t task; + struct ide_taskfile *tf = &task.tf; + + memset(&task, 0, sizeof(task)); + if (cmd == REQ_PARK_HEADS) { + drive->sleep = *(unsigned long *)rq->special; + drive->dev_flags |= IDE_DFLAG_SLEEPING; + tf->command = ATA_CMD_IDLEIMMEDIATE; + tf->feature = 0x44; + tf->lbal = 0x4c; + tf->lbam = 0x4e; + tf->lbah = 0x55; + task.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER; + } else /* cmd == REQ_UNPARK_HEADS */ + tf->command = ATA_CMD_CHK_POWER; + + task.tf_flags |= IDE_TFLAG_TF | IDE_TFLAG_DEVICE; + task.rq = rq; + drive->hwif->data_phase = task.data_phase = TASKFILE_NO_DATA; + return do_rw_taskfile(drive, &task); + } + + switch (cmd) { + case REQ_DEVSET_EXEC: + { + int err, (*setfunc)(ide_drive_t *, int) = rq->special; + + err = setfunc(drive, *(int *)&rq->cmd[1]); + if (err) + rq->errors = err; + else + err = 1; + ide_end_request(drive, err, 0); + return ide_stopped; + } + case REQ_DRIVE_RESET: + return ide_do_reset(drive); + default: + blk_dump_rq_flags(rq, "ide_special_rq - bad request"); + ide_end_request(drive, 0, 0); + return ide_stopped; + } +} + +static void ide_check_pm_state(ide_drive_t *drive, struct request *rq) +{ + struct request_pm_state *pm = rq->data; + + if (blk_pm_suspend_request(rq) && + pm->pm_step == IDE_PM_START_SUSPEND) + /* Mark drive blocked when starting the suspend sequence. */ + drive->dev_flags |= IDE_DFLAG_BLOCKED; + else if (blk_pm_resume_request(rq) && + pm->pm_step == IDE_PM_START_RESUME) { + /* + * The first thing we do on wakeup is to wait for BSY bit to + * go away (with a looong timeout) as a drive on this hwif may + * just be POSTing itself. + * We do that before even selecting as the "other" device on + * the bus may be broken enough to walk on our toes at this + * point. + */ + ide_hwif_t *hwif = drive->hwif; + int rc; +#ifdef DEBUG_PM + printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name); +#endif + rc = ide_wait_not_busy(hwif, 35000); + if (rc) + printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name); + SELECT_DRIVE(drive); + hwif->tp_ops->set_irq(hwif, 1); + rc = ide_wait_not_busy(hwif, 100000); + if (rc) + printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name); + } +} + +/** + * start_request - start of I/O and command issuing for IDE + * + * start_request() initiates handling of a new I/O request. It + * accepts commands and I/O (read/write) requests. + * + * FIXME: this function needs a rename + */ + +static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq) +{ + ide_startstop_t startstop; + + BUG_ON(!blk_rq_started(rq)); + +#ifdef DEBUG + printk("%s: start_request: current=0x%08lx\n", + HWIF(drive)->name, (unsigned long) rq); +#endif + + /* bail early if we've exceeded max_failures */ + if (drive->max_failures && (drive->failures > drive->max_failures)) { + rq->cmd_flags |= REQ_FAILED; + goto kill_rq; + } + + if (blk_pm_request(rq)) + ide_check_pm_state(drive, rq); + + SELECT_DRIVE(drive); + if (ide_wait_stat(&startstop, drive, drive->ready_stat, + ATA_BUSY | ATA_DRQ, WAIT_READY)) { + printk(KERN_ERR "%s: drive not ready for command\n", drive->name); + return startstop; + } + if (!drive->special.all) { + ide_driver_t *drv; + + /* + * We reset the drive so we need to issue a SETFEATURES. + * Do it _after_ do_special() restored device parameters. + */ + if (drive->current_speed == 0xff) + ide_config_drive_speed(drive, drive->desired_speed); + + if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) + return execute_drive_cmd(drive, rq); + else if (blk_pm_request(rq)) { + struct request_pm_state *pm = rq->data; +#ifdef DEBUG_PM + printk("%s: start_power_step(step: %d)\n", + drive->name, pm->pm_step); +#endif + startstop = ide_start_power_step(drive, rq); + if (startstop == ide_stopped && + pm->pm_step == IDE_PM_COMPLETED) + ide_complete_pm_request(drive, rq); + return startstop; + } else if (!rq->rq_disk && blk_special_request(rq)) + /* + * TODO: Once all ULDs have been modified to + * check for specific op codes rather than + * blindly accepting any special request, the + * check for ->rq_disk above may be replaced + * by a more suitable mechanism or even + * dropped entirely. + */ + return ide_special_rq(drive, rq); + + drv = *(ide_driver_t **)rq->rq_disk->private_data; + + return drv->do_request(drive, rq, rq->sector); + } + return do_special(drive); +kill_rq: + ide_kill_rq(drive, rq); + return ide_stopped; +} + +/** + * ide_stall_queue - pause an IDE device + * @drive: drive to stall + * @timeout: time to stall for (jiffies) + * + * ide_stall_queue() can be used by a drive to give excess bandwidth back + * to the hwgroup by sleeping for timeout jiffies. + */ + +void ide_stall_queue (ide_drive_t *drive, unsigned long timeout) +{ + if (timeout > WAIT_WORSTCASE) + timeout = WAIT_WORSTCASE; + drive->sleep = timeout + jiffies; + drive->dev_flags |= IDE_DFLAG_SLEEPING; +} + +EXPORT_SYMBOL(ide_stall_queue); + +#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time) + +/** + * choose_drive - select a drive to service + * @hwgroup: hardware group to select on + * + * choose_drive() selects the next drive which will be serviced. + * This is necessary because the IDE layer can't issue commands + * to both drives on the same cable, unlike SCSI. + */ + +static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup) +{ + ide_drive_t *drive, *best; + +repeat: + best = NULL; + drive = hwgroup->drive; + + /* + * drive is doing pre-flush, ordered write, post-flush sequence. even + * though that is 3 requests, it must be seen as a single transaction. + * we must not preempt this drive until that is complete + */ + if (blk_queue_flushing(drive->queue)) { + /* + * small race where queue could get replugged during + * the 3-request flush cycle, just yank the plug since + * we want it to finish asap + */ + blk_remove_plug(drive->queue); + return drive; + } + + do { + u8 dev_s = !!(drive->dev_flags & IDE_DFLAG_SLEEPING); + u8 best_s = (best && !!(best->dev_flags & IDE_DFLAG_SLEEPING)); + + if ((dev_s == 0 || time_after_eq(jiffies, drive->sleep)) && + !elv_queue_empty(drive->queue)) { + if (best == NULL || + (dev_s && (best_s == 0 || time_before(drive->sleep, best->sleep))) || + (best_s == 0 && time_before(WAKEUP(drive), WAKEUP(best)))) { + if (!blk_queue_plugged(drive->queue)) + best = drive; + } + } + } while ((drive = drive->next) != hwgroup->drive); + + if (best && (best->dev_flags & IDE_DFLAG_NICE1) && + (best->dev_flags & IDE_DFLAG_SLEEPING) == 0 && + best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) { + long t = (signed long)(WAKEUP(best) - jiffies); + if (t >= WAIT_MIN_SLEEP) { + /* + * We *may* have some time to spare, but first let's see if + * someone can potentially benefit from our nice mood today.. + */ + drive = best->next; + do { + if ((drive->dev_flags & IDE_DFLAG_SLEEPING) == 0 + && time_before(jiffies - best->service_time, WAKEUP(drive)) + && time_before(WAKEUP(drive), jiffies + t)) + { + ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP)); + goto repeat; + } + } while ((drive = drive->next) != best); + } + } + return best; +} + +/* + * Issue a new request to a drive from hwgroup + * Caller must have already done spin_lock_irqsave(&ide_lock, ..); + * + * A hwgroup is a serialized group of IDE interfaces. Usually there is + * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640) + * may have both interfaces in a single hwgroup to "serialize" access. + * Or possibly multiple ISA interfaces can share a common IRQ by being grouped + * together into one hwgroup for serialized access. + * + * Note also that several hwgroups can end up sharing a single IRQ, + * possibly along with many other devices. This is especially common in + * PCI-based systems with off-board IDE controller cards. + * + * The IDE driver uses the single global ide_lock spinlock to protect + * access to the request queues, and to protect the hwgroup->busy flag. + * + * The first thread into the driver for a particular hwgroup sets the + * hwgroup->busy flag to indicate that this hwgroup is now active, + * and then initiates processing of the top request from the request queue. + * + * Other threads attempting entry notice the busy setting, and will simply + * queue their new requests and exit immediately. Note that hwgroup->busy + * remains set even when the driver is merely awaiting the next interrupt. + * Thus, the meaning is "this hwgroup is busy processing a request". + * + * When processing of a request completes, the completing thread or IRQ-handler + * will start the next request from the queue. If no more work remains, + * the driver will clear the hwgroup->busy flag and exit. + * + * The ide_lock (spinlock) is used to protect all access to the + * hwgroup->busy flag, but is otherwise not needed for most processing in + * the driver. This makes the driver much more friendlier to shared IRQs + * than previous designs, while remaining 100% (?) SMP safe and capable. + */ +static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq) +{ + ide_drive_t *drive; + ide_hwif_t *hwif; + struct request *rq; + ide_startstop_t startstop; + int loops = 0; + + /* caller must own ide_lock */ + BUG_ON(!irqs_disabled()); + + while (!hwgroup->busy) { + hwgroup->busy = 1; + /* for atari only */ + ide_get_lock(ide_intr, hwgroup); + drive = choose_drive(hwgroup); + if (drive == NULL) { + int sleeping = 0; + unsigned long sleep = 0; /* shut up, gcc */ + hwgroup->rq = NULL; + drive = hwgroup->drive; + do { + if ((drive->dev_flags & IDE_DFLAG_SLEEPING) && + (sleeping == 0 || + time_before(drive->sleep, sleep))) { + sleeping = 1; + sleep = drive->sleep; + } + } while ((drive = drive->next) != hwgroup->drive); + if (sleeping) { + /* + * Take a short snooze, and then wake up this hwgroup again. + * This gives other hwgroups on the same a chance to + * play fairly with us, just in case there are big differences + * in relative throughputs.. don't want to hog the cpu too much. + */ + if (time_before(sleep, jiffies + WAIT_MIN_SLEEP)) + sleep = jiffies + WAIT_MIN_SLEEP; +#if 1 + if (timer_pending(&hwgroup->timer)) + printk(KERN_CRIT "ide_set_handler: timer already active\n"); +#endif + /* so that ide_timer_expiry knows what to do */ + hwgroup->sleeping = 1; + hwgroup->req_gen_timer = hwgroup->req_gen; + mod_timer(&hwgroup->timer, sleep); + /* we purposely leave hwgroup->busy==1 + * while sleeping */ + } else { + /* Ugly, but how can we sleep for the lock + * otherwise? perhaps from tq_disk? + */ + + /* for atari only */ + ide_release_lock(); + hwgroup->busy = 0; + } + + /* no more work for this hwgroup (for now) */ + return; + } + again: + hwif = HWIF(drive); + if (hwgroup->hwif->sharing_irq && hwif != hwgroup->hwif) { + /* + * set nIEN for previous hwif, drives in the + * quirk_list may not like intr setups/cleanups + */ + if (drive->quirk_list != 1) + hwif->tp_ops->set_irq(hwif, 0); + } + hwgroup->hwif = hwif; + hwgroup->drive = drive; + drive->dev_flags &= ~(IDE_DFLAG_SLEEPING | IDE_DFLAG_PARKED); + drive->service_start = jiffies; + + if (blk_queue_plugged(drive->queue)) { + printk(KERN_ERR "ide: huh? queue was plugged!\n"); + break; + } + + /* + * we know that the queue isn't empty, but this can happen + * if the q->prep_rq_fn() decides to kill a request + */ + rq = elv_next_request(drive->queue); + if (!rq) { + hwgroup->busy = 0; + break; + } + + /* + * Sanity: don't accept a request that isn't a PM request + * if we are currently power managed. This is very important as + * blk_stop_queue() doesn't prevent the elv_next_request() + * above to return us whatever is in the queue. Since we call + * ide_do_request() ourselves, we end up taking requests while + * the queue is blocked... + * + * We let requests forced at head of queue with ide-preempt + * though. I hope that doesn't happen too much, hopefully not + * unless the subdriver triggers such a thing in its own PM + * state machine. + * + * We count how many times we loop here to make sure we service + * all drives in the hwgroup without looping for ever + */ + if ((drive->dev_flags & IDE_DFLAG_BLOCKED) && + blk_pm_request(rq) == 0 && + (rq->cmd_flags & REQ_PREEMPT) == 0) { + drive = drive->next ? drive->next : hwgroup->drive; + if (loops++ < 4 && !blk_queue_plugged(drive->queue)) + goto again; + /* We clear busy, there should be no pending ATA command at this point. */ + hwgroup->busy = 0; + break; + } + + hwgroup->rq = rq; + + /* + * Some systems have trouble with IDE IRQs arriving while + * the driver is still setting things up. So, here we disable + * the IRQ used by this interface while the request is being started. + * This may look bad at first, but pretty much the same thing + * happens anyway when any interrupt comes in, IDE or otherwise + * -- the kernel masks the IRQ while it is being handled. + */ + if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) + disable_irq_nosync(hwif->irq); + spin_unlock(&ide_lock); + local_irq_enable_in_hardirq(); + /* allow other IRQs while we start this request */ + startstop = start_request(drive, rq); + spin_lock_irq(&ide_lock); + if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) + enable_irq(hwif->irq); + if (startstop == ide_stopped) + hwgroup->busy = 0; + } +} + +/* + * Passes the stuff to ide_do_request + */ +void do_ide_request(struct request_queue *q) +{ + ide_drive_t *drive = q->queuedata; + + ide_do_request(HWGROUP(drive), IDE_NO_IRQ); +} + +/* + * un-busy the hwgroup etc, and clear any pending DMA status. we want to + * retry the current request in pio mode instead of risking tossing it + * all away + */ +static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error) +{ + ide_hwif_t *hwif = HWIF(drive); + struct request *rq; + ide_startstop_t ret = ide_stopped; + + /* + * end current dma transaction + */ + + if (error < 0) { + printk(KERN_WARNING "%s: DMA timeout error\n", drive->name); + (void)hwif->dma_ops->dma_end(drive); + ret = ide_error(drive, "dma timeout error", + hwif->tp_ops->read_status(hwif)); + } else { + printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name); + hwif->dma_ops->dma_timeout(drive); + } + + /* + * disable dma for now, but remember that we did so because of + * a timeout -- we'll reenable after we finish this next request + * (or rather the first chunk of it) in pio. + */ + drive->dev_flags |= IDE_DFLAG_DMA_PIO_RETRY; + drive->retry_pio++; + ide_dma_off_quietly(drive); + + /* + * un-busy drive etc (hwgroup->busy is cleared on return) and + * make sure request is sane + */ + rq = HWGROUP(drive)->rq; + + if (!rq) + goto out; + + HWGROUP(drive)->rq = NULL; + + rq->errors = 0; + + if (!rq->bio) + goto out; + + rq->sector = rq->bio->bi_sector; + rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9; + rq->hard_cur_sectors = rq->current_nr_sectors; + rq->buffer = bio_data(rq->bio); +out: + return ret; +} + +/** + * ide_timer_expiry - handle lack of an IDE interrupt + * @data: timer callback magic (hwgroup) + * + * An IDE command has timed out before the expected drive return + * occurred. At this point we attempt to clean up the current + * mess. If the current handler includes an expiry handler then + * we invoke the expiry handler, and providing it is happy the + * work is done. If that fails we apply generic recovery rules + * invoking the handler and checking the drive DMA status. We + * have an excessively incestuous relationship with the DMA + * logic that wants cleaning up. + */ + +void ide_timer_expiry (unsigned long data) +{ + ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data; + ide_handler_t *handler; + ide_expiry_t *expiry; + unsigned long flags; + unsigned long wait = -1; + + spin_lock_irqsave(&ide_lock, flags); + + if (((handler = hwgroup->handler) == NULL) || + (hwgroup->req_gen != hwgroup->req_gen_timer)) { + /* + * Either a marginal timeout occurred + * (got the interrupt just as timer expired), + * or we were "sleeping" to give other devices a chance. + * Either way, we don't really want to complain about anything. + */ + if (hwgroup->sleeping) { + hwgroup->sleeping = 0; + hwgroup->busy = 0; + } + } else { + ide_drive_t *drive = hwgroup->drive; + if (!drive) { + printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n"); + hwgroup->handler = NULL; + } else { + ide_hwif_t *hwif; + ide_startstop_t startstop = ide_stopped; + if (!hwgroup->busy) { + hwgroup->busy = 1; /* paranoia */ + printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name); + } + if ((expiry = hwgroup->expiry) != NULL) { + /* continue */ + if ((wait = expiry(drive)) > 0) { + /* reset timer */ + hwgroup->timer.expires = jiffies + wait; + hwgroup->req_gen_timer = hwgroup->req_gen; + add_timer(&hwgroup->timer); + spin_unlock_irqrestore(&ide_lock, flags); + return; + } + } + hwgroup->handler = NULL; + /* + * We need to simulate a real interrupt when invoking + * the handler() function, which means we need to + * globally mask the specific IRQ: + */ + spin_unlock(&ide_lock); + hwif = HWIF(drive); + /* disable_irq_nosync ?? */ + disable_irq(hwif->irq); + /* local CPU only, + * as if we were handling an interrupt */ + local_irq_disable(); + if (hwgroup->polling) { + startstop = handler(drive); + } else if (drive_is_ready(drive)) { + if (drive->waiting_for_dma) + hwif->dma_ops->dma_lost_irq(drive); + (void)ide_ack_intr(hwif); + printk(KERN_WARNING "%s: lost interrupt\n", drive->name); + startstop = handler(drive); + } else { + if (drive->waiting_for_dma) { + startstop = ide_dma_timeout_retry(drive, wait); + } else + startstop = + ide_error(drive, "irq timeout", + hwif->tp_ops->read_status(hwif)); + } + drive->service_time = jiffies - drive->service_start; + spin_lock_irq(&ide_lock); + enable_irq(hwif->irq); + if (startstop == ide_stopped) + hwgroup->busy = 0; + } + } + ide_do_request(hwgroup, IDE_NO_IRQ); + spin_unlock_irqrestore(&ide_lock, flags); +} + +/** + * unexpected_intr - handle an unexpected IDE interrupt + * @irq: interrupt line + * @hwgroup: hwgroup being processed + * + * There's nothing really useful we can do with an unexpected interrupt, + * other than reading the status register (to clear it), and logging it. + * There should be no way that an irq can happen before we're ready for it, + * so we needn't worry much about losing an "important" interrupt here. + * + * On laptops (and "green" PCs), an unexpected interrupt occurs whenever + * the drive enters "idle", "standby", or "sleep" mode, so if the status + * looks "good", we just ignore the interrupt completely. + * + * This routine assumes __cli() is in effect when called. + * + * If an unexpected interrupt happens on irq15 while we are handling irq14 + * and if the two interfaces are "serialized" (CMD640), then it looks like + * we could screw up by interfering with a new request being set up for + * irq15. + * + * In reality, this is a non-issue. The new command is not sent unless + * the drive is ready to accept one, in which case we know the drive is + * not trying to interrupt us. And ide_set_handler() is always invoked + * before completing the issuance of any new drive command, so we will not + * be accidentally invoked as a result of any valid command completion + * interrupt. + * + * Note that we must walk the entire hwgroup here. We know which hwif + * is doing the current command, but we don't know which hwif burped + * mysteriously. + */ + +static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup) +{ + u8 stat; + ide_hwif_t *hwif = hwgroup->hwif; + + /* + * handle the unexpected interrupt + */ + do { + if (hwif->irq == irq) { + stat = hwif->tp_ops->read_status(hwif); + + if (!OK_STAT(stat, ATA_DRDY, BAD_STAT)) { + /* Try to not flood the console with msgs */ + static unsigned long last_msgtime, count; + ++count; + if (time_after(jiffies, last_msgtime + HZ)) { + last_msgtime = jiffies; + printk(KERN_ERR "%s%s: unexpected interrupt, " + "status=0x%02x, count=%ld\n", + hwif->name, + (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count); + } + } + } + } while ((hwif = hwif->next) != hwgroup->hwif); +} + +/** + * ide_intr - default IDE interrupt handler + * @irq: interrupt number + * @dev_id: hwif group + * @regs: unused weirdness from the kernel irq layer + * + * This is the default IRQ handler for the IDE layer. You should + * not need to override it. If you do be aware it is subtle in + * places + * + * hwgroup->hwif is the interface in the group currently performing + * a command. hwgroup->drive is the drive and hwgroup->handler is + * the IRQ handler to call. As we issue a command the handlers + * step through multiple states, reassigning the handler to the + * next step in the process. Unlike a smart SCSI controller IDE + * expects the main processor to sequence the various transfer + * stages. We also manage a poll timer to catch up with most + * timeout situations. There are still a few where the handlers + * don't ever decide to give up. + * + * The handler eventually returns ide_stopped to indicate the + * request completed. At this point we issue the next request + * on the hwgroup and the process begins again. + */ + +irqreturn_t ide_intr (int irq, void *dev_id) +{ + unsigned long flags; + ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id; + ide_hwif_t *hwif; + ide_drive_t *drive; + ide_handler_t *handler; + ide_startstop_t startstop; + + spin_lock_irqsave(&ide_lock, flags); + hwif = hwgroup->hwif; + + if (!ide_ack_intr(hwif)) { + spin_unlock_irqrestore(&ide_lock, flags); + return IRQ_NONE; + } + + if ((handler = hwgroup->handler) == NULL || hwgroup->polling) { + /* + * Not expecting an interrupt from this drive. + * That means this could be: + * (1) an interrupt from another PCI device + * sharing the same PCI INT# as us. + * or (2) a drive just entered sleep or standby mode, + * and is interrupting to let us know. + * or (3) a spurious interrupt of unknown origin. + * + * For PCI, we cannot tell the difference, + * so in that case we just ignore it and hope it goes away. + * + * FIXME: unexpected_intr should be hwif-> then we can + * remove all the ifdef PCI crap + */ +#ifdef CONFIG_BLK_DEV_IDEPCI + if (hwif->chipset != ide_pci) +#endif /* CONFIG_BLK_DEV_IDEPCI */ + { + /* + * Probably not a shared PCI interrupt, + * so we can safely try to do something about it: + */ + unexpected_intr(irq, hwgroup); +#ifdef CONFIG_BLK_DEV_IDEPCI + } else { + /* + * Whack the status register, just in case + * we have a leftover pending IRQ. + */ + (void)hwif->tp_ops->read_status(hwif); +#endif /* CONFIG_BLK_DEV_IDEPCI */ + } + spin_unlock_irqrestore(&ide_lock, flags); + return IRQ_NONE; + } + drive = hwgroup->drive; + if (!drive) { + /* + * This should NEVER happen, and there isn't much + * we could do about it here. + * + * [Note - this can occur if the drive is hot unplugged] + */ + spin_unlock_irqrestore(&ide_lock, flags); + return IRQ_HANDLED; + } + if (!drive_is_ready(drive)) { + /* + * This happens regularly when we share a PCI IRQ with + * another device. Unfortunately, it can also happen + * with some buggy drives that trigger the IRQ before + * their status register is up to date. Hopefully we have + * enough advance overhead that the latter isn't a problem. + */ + spin_unlock_irqrestore(&ide_lock, flags); + return IRQ_NONE; + } + if (!hwgroup->busy) { + hwgroup->busy = 1; /* paranoia */ + printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name); + } + hwgroup->handler = NULL; + hwgroup->req_gen++; + del_timer(&hwgroup->timer); + spin_unlock(&ide_lock); + + if (hwif->port_ops && hwif->port_ops->clear_irq) + hwif->port_ops->clear_irq(drive); + + if (drive->dev_flags & IDE_DFLAG_UNMASK) + local_irq_enable_in_hardirq(); + + /* service this interrupt, may set handler for next interrupt */ + startstop = handler(drive); + + spin_lock_irq(&ide_lock); + /* + * Note that handler() may have set things up for another + * interrupt to occur soon, but it cannot happen until + * we exit from this routine, because it will be the + * same irq as is currently being serviced here, and Linux + * won't allow another of the same (on any CPU) until we return. + */ + drive->service_time = jiffies - drive->service_start; + if (startstop == ide_stopped) { + if (hwgroup->handler == NULL) { /* paranoia */ + hwgroup->busy = 0; + ide_do_request(hwgroup, hwif->irq); + } else { + printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler " + "on exit\n", drive->name); + } + } + spin_unlock_irqrestore(&ide_lock, flags); + return IRQ_HANDLED; +} + +/** + * ide_do_drive_cmd - issue IDE special command + * @drive: device to issue command + * @rq: request to issue + * + * This function issues a special IDE device request + * onto the request queue. + * + * the rq is queued at the head of the request queue, displacing + * the currently-being-processed request and this function + * returns immediately without waiting for the new rq to be + * completed. This is VERY DANGEROUS, and is intended for + * careful use by the ATAPI tape/cdrom driver code. + */ + +void ide_do_drive_cmd(ide_drive_t *drive, struct request *rq) +{ + unsigned long flags; + ide_hwgroup_t *hwgroup = HWGROUP(drive); + + spin_lock_irqsave(&ide_lock, flags); + hwgroup->rq = NULL; + __elv_add_request(drive->queue, rq, ELEVATOR_INSERT_FRONT, 0); + blk_start_queueing(drive->queue); + spin_unlock_irqrestore(&ide_lock, flags); +} + +EXPORT_SYMBOL(ide_do_drive_cmd); + +void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma) +{ + ide_hwif_t *hwif = drive->hwif; + ide_task_t task; + + memset(&task, 0, sizeof(task)); + task.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM | + IDE_TFLAG_OUT_FEATURE | tf_flags; + task.tf.feature = dma; /* Use PIO/DMA */ + task.tf.lbam = bcount & 0xff; + task.tf.lbah = (bcount >> 8) & 0xff; + + ide_tf_dump(drive->name, &task.tf); + hwif->tp_ops->set_irq(hwif, 1); + SELECT_MASK(drive, 0); + hwif->tp_ops->tf_load(drive, &task); +} + +EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load); + +void ide_pad_transfer(ide_drive_t *drive, int write, int len) +{ + ide_hwif_t *hwif = drive->hwif; + u8 buf[4] = { 0 }; + + while (len > 0) { + if (write) + hwif->tp_ops->output_data(drive, NULL, buf, min(4, len)); + else + hwif->tp_ops->input_data(drive, NULL, buf, min(4, len)); + len -= 4; + } +} +EXPORT_SYMBOL_GPL(ide_pad_transfer); |
