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linux/drivers/ata/libata.h
Tejun Heo 5ddf24c5ea libata: implement EH fast drain
In most cases, when EH is scheduled, all in-flight commands are
aborted causing EH to kick in immediately.  However, in some cases
(especially with PMP), it's unclear which commands are affected by the
error condition and although aborting all in-flight commands work, it
isn't optimal and may cause unnecessary disruption.  On the other
hand, waiting for in-flight commands to drain themselves can take up
to 30seconds.

This patch implements EH fast drain to handle such situations.  It
gives in-flight commands some time to finish up but doesn't wait for
too long.  After EH is scheduled, fast drain timer is started and if
no other completion occurs in ATA_EH_FASTDRAIN_INTERVAL all in-flight
commands are aborted.  If any completion occurred in the interval, the
port is given another interval to finish up itself.

Currently ATA_EH_FASTDRAIN_INTERVAL is 3 secs which should be enough
for finishing up most commands.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-07-20 08:26:26 -04:00

162 lines
6.6 KiB
C

/*
* libata.h - helper library for ATA
*
* Copyright 2003-2004 Red Hat, Inc. All rights reserved.
* Copyright 2003-2004 Jeff Garzik
*
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*
*
* libata documentation is available via 'make {ps|pdf}docs',
* as Documentation/DocBook/libata.*
*
*/
#ifndef __LIBATA_H__
#define __LIBATA_H__
#define DRV_NAME "libata"
struct ata_scsi_args {
struct ata_device *dev;
u16 *id;
struct scsi_cmnd *cmd;
void (*done)(struct scsi_cmnd *);
};
/* libata-core.c */
enum {
/* flags for ata_dev_read_id() */
ATA_READID_POSTRESET = (1 << 0), /* reading ID after reset */
/* selector for ata_down_xfermask_limit() */
ATA_DNXFER_PIO = 0, /* speed down PIO */
ATA_DNXFER_DMA = 1, /* speed down DMA */
ATA_DNXFER_40C = 2, /* apply 40c cable limit */
ATA_DNXFER_FORCE_PIO = 3, /* force PIO */
ATA_DNXFER_FORCE_PIO0 = 4, /* force PIO0 */
ATA_DNXFER_QUIET = (1 << 31),
};
extern unsigned int ata_print_id;
extern struct workqueue_struct *ata_aux_wq;
extern int atapi_enabled;
extern int atapi_dmadir;
extern int libata_fua;
extern int libata_noacpi;
extern struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev);
extern int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
u64 block, u32 n_block, unsigned int tf_flags,
unsigned int tag);
extern u64 ata_tf_read_block(struct ata_taskfile *tf, struct ata_device *dev);
extern void ata_dev_disable(struct ata_device *dev);
extern void ata_port_flush_task(struct ata_port *ap);
extern unsigned ata_exec_internal(struct ata_device *dev,
struct ata_taskfile *tf, const u8 *cdb,
int dma_dir, void *buf, unsigned int buflen);
extern unsigned ata_exec_internal_sg(struct ata_device *dev,
struct ata_taskfile *tf, const u8 *cdb,
int dma_dir, struct scatterlist *sg,
unsigned int n_elem);
extern unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd);
extern int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
unsigned int flags, u16 *id);
extern int ata_dev_reread_id(struct ata_device *dev, unsigned int readid_flags);
extern int ata_dev_revalidate(struct ata_device *dev, unsigned int readid_flags);
extern int ata_dev_configure(struct ata_device *dev);
extern int sata_down_spd_limit(struct ata_port *ap);
extern int sata_set_spd_needed(struct ata_port *ap);
extern int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel);
extern int ata_set_mode(struct ata_port *ap, struct ata_device **r_failed_dev);
extern void ata_sg_clean(struct ata_queued_cmd *qc);
extern void ata_qc_free(struct ata_queued_cmd *qc);
extern void ata_qc_issue(struct ata_queued_cmd *qc);
extern void __ata_qc_complete(struct ata_queued_cmd *qc);
extern int ata_check_atapi_dma(struct ata_queued_cmd *qc);
extern void ata_dev_select(struct ata_port *ap, unsigned int device,
unsigned int wait, unsigned int can_sleep);
extern void swap_buf_le16(u16 *buf, unsigned int buf_words);
extern int ata_flush_cache(struct ata_device *dev);
extern void ata_dev_init(struct ata_device *dev);
extern int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg);
extern int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg);
extern struct ata_port *ata_port_alloc(struct ata_host *host);
/* libata-acpi.c */
#ifdef CONFIG_ATA_ACPI
extern void ata_acpi_associate(struct ata_host *host);
extern int ata_acpi_on_suspend(struct ata_port *ap);
extern void ata_acpi_on_resume(struct ata_port *ap);
extern int ata_acpi_on_devcfg(struct ata_device *adev);
#else
static inline void ata_acpi_associate(struct ata_host *host) { }
static inline int ata_acpi_on_suspend(struct ata_port *ap) { return 0; }
static inline void ata_acpi_on_resume(struct ata_port *ap) { }
static inline int ata_acpi_on_devcfg(struct ata_device *adev) { return 0; }
#endif
/* libata-scsi.c */
extern int ata_scsi_add_hosts(struct ata_host *host,
struct scsi_host_template *sht);
extern void ata_scsi_scan_host(struct ata_port *ap, int sync);
extern int ata_scsi_offline_dev(struct ata_device *dev);
extern void ata_scsi_hotplug(struct work_struct *work);
extern unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf,
unsigned int buflen);
extern unsigned int ata_scsiop_inq_00(struct ata_scsi_args *args, u8 *rbuf,
unsigned int buflen);
extern unsigned int ata_scsiop_inq_80(struct ata_scsi_args *args, u8 *rbuf,
unsigned int buflen);
extern unsigned int ata_scsiop_inq_83(struct ata_scsi_args *args, u8 *rbuf,
unsigned int buflen);
extern unsigned int ata_scsiop_noop(struct ata_scsi_args *args, u8 *rbuf,
unsigned int buflen);
extern unsigned int ata_scsiop_sync_cache(struct ata_scsi_args *args, u8 *rbuf,
unsigned int buflen);
extern unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf,
unsigned int buflen);
extern unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf,
unsigned int buflen);
extern unsigned int ata_scsiop_report_luns(struct ata_scsi_args *args, u8 *rbuf,
unsigned int buflen);
extern void ata_scsi_badcmd(struct scsi_cmnd *cmd,
void (*done)(struct scsi_cmnd *),
u8 asc, u8 ascq);
extern void ata_scsi_set_sense(struct scsi_cmnd *cmd,
u8 sk, u8 asc, u8 ascq);
extern void ata_scsi_rbuf_fill(struct ata_scsi_args *args,
unsigned int (*actor) (struct ata_scsi_args *args,
u8 *rbuf, unsigned int buflen));
extern void ata_schedule_scsi_eh(struct Scsi_Host *shost);
extern void ata_scsi_dev_rescan(struct work_struct *work);
extern int ata_bus_probe(struct ata_port *ap);
/* libata-eh.c */
extern enum scsi_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd);
extern void ata_scsi_error(struct Scsi_Host *host);
extern void ata_port_wait_eh(struct ata_port *ap);
extern void ata_eh_fastdrain_timerfn(unsigned long arg);
extern void ata_qc_schedule_eh(struct ata_queued_cmd *qc);
/* libata-sff.c */
extern u8 ata_irq_on(struct ata_port *ap);
#endif /* __LIBATA_H__ */