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/*
* scsi_obsolete.c Copyright (C) 1992 Drew Eckhardt
* Copyright (C) 1993, 1994, 1995 Eric Youngdale
*
* generic mid-level SCSI driver
* Initial versions: Drew Eckhardt
* Subsequent revisions: Eric Youngdale
*
* <drew@colorado.edu>
*
* Bug correction thanks go to :
* Rik Faith <faith@cs.unc.edu>
* Tommy Thorn <tthorn>
* Thomas Wuensche <tw@fgb1.fgb.mw.tu-muenchen.de>
*
* Modified by Eric Youngdale eric@andante.org to
* add scatter-gather, multiple outstanding request, and other
* enhancements.
*
* Native multichannel, wide scsi, /proc/scsi and hot plugging
* support added by Michael Neuffer <mike@i-connect.net>
*
* Major improvements to the timeout, abort, and reset processing,
* as well as performance modifications for large queue depths by
* Leonard N. Zubkoff <lnz@dandelion.com>
*
* Improved compatibility with 2.0 behaviour by Manfred Spraul
* <masp0008@stud.uni-sb.de>
*/
/*
*#########################################################################
*#########################################################################
*#########################################################################
*#########################################################################
* NOTE - NOTE - NOTE - NOTE - NOTE - NOTE - NOTE
*
*#########################################################################
*#########################################################################
*#########################################################################
*#########################################################################
*
* This file contains the 'old' scsi error handling. It is only present
* while the new error handling code is being debugged, and while the low
* level drivers are being converted to use the new code. Once the last
* driver uses the new code this *ENTIRE* file will be nuked.
*/
#define __NO_VERSION__
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/stat.h>
#include <linux/blk.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <asm/system.h>
#include <asm/irq.h>
#include <asm/dma.h>
#include "scsi.h"
#include "hosts.h"
#include "constants.h"
#undef USE_STATIC_SCSI_MEMORY
/*
static const char RCSid[] = "$Header: /mnt/ide/home/eric/CVSROOT/linux/drivers/scsi/scsi_obsolete.c,v 1.1 1997/05/18 23:27:21 eric Exp $";
*/
#define INTERNAL_ERROR (panic ("Internal error in file %s, line %d.\n", __FILE__, __LINE__))
static int scsi_abort(Scsi_Cmnd *, int code);
static int scsi_reset(Scsi_Cmnd *, unsigned int);
extern void scsi_old_done(Scsi_Cmnd * SCpnt);
int update_timeout(Scsi_Cmnd *, int);
extern void scsi_old_times_out(Scsi_Cmnd * SCpnt);
extern int scsi_dispatch_cmd(Scsi_Cmnd * SCpnt);
#define SCSI_BLOCK(HOST) (HOST->can_queue && HOST->host_busy >= HOST->can_queue)
static unsigned char generic_sense[6] =
{REQUEST_SENSE, 0, 0, 0, 255, 0};
/*
* This is the number of clock ticks we should wait before we time out
* and abort the command. This is for where the scsi.c module generates
* the command, not where it originates from a higher level, in which
* case the timeout is specified there.
*
* ABORT_TIMEOUT and RESET_TIMEOUT are the timeouts for RESET and ABORT
* respectively.
*/
#ifdef DEBUG_TIMEOUT
static void scsi_dump_status(void);
#endif
#ifdef DEBUG
#define SCSI_TIMEOUT (5*HZ)
#else
#define SCSI_TIMEOUT (2*HZ)
#endif
#ifdef DEBUG
#define SENSE_TIMEOUT SCSI_TIMEOUT
#define ABORT_TIMEOUT SCSI_TIMEOUT
#define RESET_TIMEOUT SCSI_TIMEOUT
#else
#define SENSE_TIMEOUT (5*HZ/10)
#define RESET_TIMEOUT (5*HZ/10)
#define ABORT_TIMEOUT (5*HZ/10)
#endif
/* Do not call reset on error if we just did a reset within 15 sec. */
#define MIN_RESET_PERIOD (15*HZ)
/*
* Flag bits for the internal_timeout array
*/
#define IN_ABORT 1
#define IN_RESET 2
#define IN_RESET2 4
#define IN_RESET3 8
/*
* This is our time out function, called when the timer expires for a
* given host adapter. It will attempt to abort the currently executing
* command, that failing perform a kernel panic.
*/
void scsi_old_times_out(Scsi_Cmnd * SCpnt)
{
unsigned long flags;
spin_lock_irqsave(&io_request_lock, flags);
/* Set the serial_number_at_timeout to the current serial_number */
SCpnt->serial_number_at_timeout = SCpnt->serial_number;
switch (SCpnt->internal_timeout & (IN_ABORT | IN_RESET | IN_RESET2 | IN_RESET3)) {
case NORMAL_TIMEOUT:
{
#ifdef DEBUG_TIMEOUT
scsi_dump_status();
#endif
}
if (!scsi_abort(SCpnt, DID_TIME_OUT))
break;
case IN_ABORT:
printk("SCSI host %d abort (pid %ld) timed out - resetting\n",
SCpnt->host->host_no, SCpnt->pid);
if (!scsi_reset(SCpnt, SCSI_RESET_ASYNCHRONOUS))
break;
case IN_RESET:
case (IN_ABORT | IN_RESET):
/* This might be controversial, but if there is a bus hang,
* you might conceivably want the machine up and running
* esp if you have an ide disk.
*/
printk("SCSI host %d channel %d reset (pid %ld) timed out - "
"trying harder\n",
SCpnt->host->host_no, SCpnt->channel, SCpnt->pid);
SCpnt->internal_timeout &= ~IN_RESET;
SCpnt->internal_timeout |= IN_RESET2;
scsi_reset(SCpnt,
SCSI_RESET_ASYNCHRONOUS | SCSI_RESET_SUGGEST_BUS_RESET);
break;
case IN_RESET2:
case (IN_ABORT | IN_RESET2):
/* Obviously the bus reset didn't work.
* Let's try even harder and call for an HBA reset.
* Maybe the HBA itself crashed and this will shake it loose.
*/
printk("SCSI host %d reset (pid %ld) timed out - trying to shake it loose\n",
SCpnt->host->host_no, SCpnt->pid);
SCpnt->internal_timeout &= ~(IN_RESET | IN_RESET2);
SCpnt->internal_timeout |= IN_RESET3;
scsi_reset(SCpnt,
SCSI_RESET_ASYNCHRONOUS | SCSI_RESET_SUGGEST_HOST_RESET);
break;
default:
printk("SCSI host %d reset (pid %ld) timed out again -\n",
SCpnt->host->host_no, SCpnt->pid);
printk("probably an unrecoverable SCSI bus or device hang.\n");
break;
}
spin_unlock_irqrestore(&io_request_lock, flags);
}
/*
* From what I can find in scsi_obsolete.c, this function is only called
* by scsi_old_done and scsi_reset. Both of these functions run with the
* io_request_lock already held, so we need do nothing here about grabbing
* any locks.
*/
static void scsi_request_sense(Scsi_Cmnd * SCpnt)
{
SCpnt->flags |= WAS_SENSE | ASKED_FOR_SENSE;
update_timeout(SCpnt, SENSE_TIMEOUT);
memcpy((void *) SCpnt->cmnd, (void *) generic_sense,
sizeof(generic_sense));
memset((void *) SCpnt->sense_buffer, 0,
sizeof(SCpnt->sense_buffer));
if (SCpnt->device->scsi_level <= SCSI_2)
SCpnt->cmnd[1] = SCpnt->lun << 5;
SCpnt->cmnd[4] = sizeof(SCpnt->sense_buffer);
SCpnt->request_buffer = &SCpnt->sense_buffer;
SCpnt->request_bufflen = sizeof(SCpnt->sense_buffer);
SCpnt->use_sg = 0;
SCpnt->cmd_len = COMMAND_SIZE(SCpnt->cmnd[0]);
SCpnt->result = 0;
SCpnt->sc_data_direction = SCSI_DATA_READ;
/*
* Ugly, ugly. The newer interfaces all assume that the lock
* isn't held. Mustn't disappoint, or we deadlock the system.
*/
spin_unlock_irq(&io_request_lock);
scsi_dispatch_cmd(SCpnt);
spin_lock_irq(&io_request_lock);
}
static int check_sense(Scsi_Cmnd * SCpnt)
{
/* If there is no sense information, request it. If we have already
* requested it, there is no point in asking again - the firmware must
* be confused.
*/
if (((SCpnt->sense_buffer[0] & 0x70) >> 4) != 7) {
if (!(SCpnt->flags & ASKED_FOR_SENSE))
return SUGGEST_SENSE;
else
return SUGGEST_RETRY;
}
SCpnt->flags &= ~ASKED_FOR_SENSE;
#ifdef DEBUG_INIT
printk("scsi%d, channel%d : ", SCpnt->host->host_no, SCpnt->channel);
print_sense("", SCpnt);
printk("\n");
#endif
if (SCpnt->sense_buffer[2] & 0xe0)
return SUGGEST_ABORT;
switch (SCpnt->sense_buffer[2] & 0xf) {
case NO_SENSE:
return 0;
case RECOVERED_ERROR:
return SUGGEST_IS_OK;
case ABORTED_COMMAND:
return SUGGEST_RETRY;
case NOT_READY:
case UNIT_ATTENTION:
/*
* If we are expecting a CC/UA because of a bus reset that we
* performed, treat this just as a retry. Otherwise this is
* information that we should pass up to the upper-level driver
* so that we can deal with it there.
*/
if (SCpnt->device->expecting_cc_ua) {
SCpnt->device->expecting_cc_ua = 0;
return SUGGEST_RETRY;
}
return SUGGEST_ABORT;
/* these three are not supported */
case COPY_ABORTED:
case VOLUME_OVERFLOW:
case MISCOMPARE:
case MEDIUM_ERROR:
return SUGGEST_REMAP;
case BLANK_CHECK:
case DATA_PROTECT:
case HARDWARE_ERROR:
case ILLEGAL_REQUEST:
default:
return SUGGEST_ABORT;
}
}
/* This function is the mid-level interrupt routine, which decides how
* to handle error conditions. Each invocation of this function must
* do one and *only* one of the following:
*
* (1) Call last_cmnd[host].done. This is done for fatal errors and
* normal completion, and indicates that the handling for this
* request is complete.
* (2) Call internal_cmnd to requeue the command. This will result in
* scsi_done being called again when the retry is complete.
* (3) Call scsi_request_sense. This asks the host adapter/drive for
* more information about the error condition. When the information
* is available, scsi_done will be called again.
* (4) Call reset(). This is sort of a last resort, and the idea is that
* this may kick things loose and get the drive working again. reset()
* automatically calls scsi_request_sense, and thus scsi_done will be
* called again once the reset is complete.
*
* If none of the above actions are taken, the drive in question
* will hang. If more than one of the above actions are taken by
* scsi_done, then unpredictable behavior will result.
*/
void scsi_old_done(Scsi_Cmnd * SCpnt)
{
int status = 0;
int exit = 0;
int checked;
int oldto;
struct Scsi_Host *host = SCpnt->host;
Scsi_Device * device = SCpnt->device;
int result = SCpnt->result;
SCpnt->serial_number = 0;
SCpnt->serial_number_at_timeout = 0;
oldto = update_timeout(SCpnt, 0);
#ifdef DEBUG_TIMEOUT
if (result)
printk("Non-zero result in scsi_done %x %d:%d\n",
result, SCpnt->target, SCpnt->lun);
#endif
/* If we requested an abort, (and we got it) then fix up the return
* status to say why
*/
if (host_byte(result) == DID_ABORT && SCpnt->abort_reason)
SCpnt->result = result = (result & 0xff00ffff) |
(SCpnt->abort_reason << 16);
#define CMD_FINISHED 0
#define MAYREDO 1
#define REDO 3
#define PENDING 4
#ifdef DEBUG
printk("In scsi_done(host = %d, result = %06x)\n", host->host_no, result);
#endif
if (SCpnt->flags & SYNC_RESET) {
/*
* The behaviou of scsi_reset(SYNC) was changed in 2.1.? .
* The scsi mid-layer does a REDO after every sync reset, the driver
* must not do that any more. In order to prevent old drivers from
* crashing, all scsi_done() calls during sync resets are ignored.
*/
printk("scsi%d: device driver called scsi_done() "
"for a synchronous reset.\n", SCpnt->host->host_no);
return;
}
if (SCpnt->flags & WAS_SENSE) {
SCpnt->use_sg = SCpnt->old_use_sg;
SCpnt->cmd_len = SCpnt->old_cmd_len;
SCpnt->sc_data_direction = SCpnt->sc_old_data_direction;
SCpnt->underflow = SCpnt->old_underflow;
}
switch (host_byte(result)) {
case DID_OK:
if (status_byte(result) && (SCpnt->flags & WAS_SENSE))
/* Failed to obtain sense information */
{
SCpnt->flags &= ~WAS_SENSE;
#if 0 /* This cannot possibly be correct. */
SCpnt->internal_timeout &= ~SENSE_TIMEOUT;
#endif
if (!(SCpnt->flags & WAS_RESET)) {
printk("scsi%d : channel %d target %d lun %d request sense"
" failed, performing reset.\n",
SCpnt->host->host_no, SCpnt->channel, SCpnt->target,
SCpnt->lun);
scsi_reset(SCpnt, SCSI_RESET_SYNCHRONOUS);
status = REDO;
break;
} else {
exit = (DRIVER_HARD | SUGGEST_ABORT);
status = CMD_FINISHED;
}
} else
switch (msg_byte(result)) {
case COMMAND_COMPLETE:
switch (status_byte(result)) {
case GOOD:
if (SCpnt->flags & WAS_SENSE) {
#ifdef DEBUG
printk("In scsi_done, GOOD status, COMMAND COMPLETE, "
"parsing sense information.\n");
#endif
SCpnt->flags &= ~WAS_SENSE;
#if 0 /* This cannot possibly be correct. */
SCpnt->internal_timeout &= ~SENSE_TIMEOUT;
#endif
switch (checked = check_sense(SCpnt)) {
case SUGGEST_SENSE:
case 0:
#ifdef DEBUG
printk("NO SENSE. status = REDO\n");
#endif
update_timeout(SCpnt, oldto);
status = REDO;
break;
case SUGGEST_IS_OK:
break;
case SUGGEST_REMAP:
#ifdef DEBUG
printk("SENSE SUGGEST REMAP - status = CMD_FINISHED\n");
#endif
status = CMD_FINISHED;
exit = DRIVER_SENSE | SUGGEST_ABORT;
break;
case SUGGEST_RETRY:
#ifdef DEBUG
printk("SENSE SUGGEST RETRY - status = MAYREDO\n");
#endif
status = MAYREDO;
exit = DRIVER_SENSE | SUGGEST_RETRY;
break;
case SUGGEST_ABORT:
#ifdef DEBUG
printk("SENSE SUGGEST ABORT - status = CMD_FINISHED");
#endif
status = CMD_FINISHED;
exit = DRIVER_SENSE | SUGGEST_ABORT;
break;
default:
printk("Internal error %s %d \n", __FILE__,
__LINE__);
}
}
/* end WAS_SENSE */
else {
#ifdef DEBUG
printk("COMMAND COMPLETE message returned, "
"status = CMD_FINISHED. \n");
#endif
exit = DRIVER_OK;
status = CMD_FINISHED;
}
break;
case CHECK_CONDITION:
case COMMAND_TERMINATED:
switch (check_sense(SCpnt)) {
case 0:
update_timeout(SCpnt, oldto);
status = REDO;
break;
case SUGGEST_REMAP:
status = CMD_FINISHED;
exit = DRIVER_SENSE | SUGGEST_ABORT;
break;
case SUGGEST_RETRY:
status = MAYREDO;
exit = DRIVER_SENSE | SUGGEST_RETRY;
break;
case SUGGEST_ABORT:
status = CMD_FINISHED;
exit = DRIVER_SENSE | SUGGEST_ABORT;
break;
case SUGGEST_SENSE:
scsi_request_sense(SCpnt);
status = PENDING;
break;
}
break;
case CONDITION_GOOD:
case INTERMEDIATE_GOOD:
case INTERMEDIATE_C_GOOD:
break;
case BUSY:
case QUEUE_FULL:
update_timeout(SCpnt, oldto);
status = REDO;
break;
case RESERVATION_CONFLICT:
printk("scsi%d, channel %d : RESERVATION CONFLICT performing"
" reset.\n", SCpnt->host->host_no, SCpnt->channel);
scsi_reset(SCpnt, SCSI_RESET_SYNCHRONOUS);
status = REDO;
break;
default:
printk("Internal error %s %d \n"
"status byte = %d \n", __FILE__,
__LINE__, status_byte(result));
}
break;
default:
panic("scsi: unsupported message byte %d received\n",
msg_byte(result));
}
break;
case DID_TIME_OUT:
#ifdef DEBUG
printk("Host returned DID_TIME_OUT - ");
#endif
if (SCpnt->flags & WAS_TIMEDOUT) {
#ifdef DEBUG
printk("Aborting\n");
#endif
/*
Allow TEST_UNIT_READY and INQUIRY commands to timeout early
without causing resets. All other commands should be retried.
*/
if (SCpnt->cmnd[0] != TEST_UNIT_READY &&
SCpnt->cmnd[0] != INQUIRY)
status = MAYREDO;
exit = (DRIVER_TIMEOUT | SUGGEST_ABORT);
} else {
#ifdef DEBUG
printk("Retrying.\n");
#endif
SCpnt->flags |= WAS_TIMEDOUT;
SCpnt->internal_timeout &= ~IN_ABORT;
status = REDO;
}
break;
case DID_BUS_BUSY:
case DID_PARITY:
status = REDO;
break;
case DID_NO_CONNECT:
#ifdef DEBUG
printk("Couldn't connect.\n");
#endif
exit = (DRIVER_HARD | SUGGEST_ABORT);
break;
case DID_ERROR:
status = MAYREDO;
exit = (DRIVER_HARD | SUGGEST_ABORT);
break;
case DID_BAD_TARGET:
case DID_ABORT:
exit = (DRIVER_INVALID | SUGGEST_ABORT);
break;
case DID_RESET:
if (SCpnt->flags & IS_RESETTING) {
SCpnt->flags &= ~IS_RESETTING;
status = REDO;
break;
}
if (msg_byte(result) == GOOD &&
status_byte(result) == CHECK_CONDITION) {
switch (check_sense(SCpnt)) {
case 0:
update_timeout(SCpnt, oldto);
status = REDO;
break;
case SUGGEST_REMAP:
case SUGGEST_RETRY:
status = MAYREDO;
exit = DRIVER_SENSE | SUGGEST_RETRY;
break;
case SUGGEST_ABORT:
status = CMD_FINISHED;
exit = DRIVER_SENSE | SUGGEST_ABORT;
break;
case SUGGEST_SENSE:
scsi_request_sense(SCpnt);
status = PENDING;
break;
}
} else {
status = REDO;
exit = SUGGEST_RETRY;
}
break;
default:
exit = (DRIVER_ERROR | SUGGEST_DIE);
}
switch (status) {
case CMD_FINISHED:
case PENDING:
break;
case MAYREDO:
#ifdef DEBUG
printk("In MAYREDO, allowing %d retries, have %d\n",
SCpnt->allowed, SCpnt->retries);
#endif
if ((++SCpnt->retries) < SCpnt->allowed) {
if ((SCpnt->retries >= (SCpnt->allowed >> 1))
&& !(SCpnt->host->resetting && time_before(jiffies, SCpnt->host->last_reset + MIN_RESET_PERIOD))
&& !(SCpnt->flags & WAS_RESET)) {
printk("scsi%d channel %d : resetting for second half of retries.\n",
SCpnt->host->host_no, SCpnt->channel);
scsi_reset(SCpnt, SCSI_RESET_SYNCHRONOUS);
/* fall through to REDO */
}
} else {
status = CMD_FINISHED;
break;
}
/* fall through to REDO */
case REDO:
if (SCpnt->flags & WAS_SENSE)
scsi_request_sense(SCpnt);
else {
memcpy((void *) SCpnt->cmnd,
(void *) SCpnt->data_cmnd,
sizeof(SCpnt->data_cmnd));
memset((void *) SCpnt->sense_buffer, 0,
sizeof(SCpnt->sense_buffer));
SCpnt->request_buffer = SCpnt->buffer;
SCpnt->request_bufflen = SCpnt->bufflen;
SCpnt->use_sg = SCpnt->old_use_sg;
SCpnt->cmd_len = SCpnt->old_cmd_len;
SCpnt->sc_data_direction = SCpnt->sc_old_data_direction;
SCpnt->underflow = SCpnt->old_underflow;
SCpnt->result = 0;
/*
* Ugly, ugly. The newer interfaces all
* assume that the lock isn't held. Mustn't
* disappoint, or we deadlock the system.
*/
spin_unlock_irq(&io_request_lock);
scsi_dispatch_cmd(SCpnt);
spin_lock_irq(&io_request_lock);
}
break;
default:
INTERNAL_ERROR;
}
if (status == CMD_FINISHED) {
Scsi_Request *SRpnt;
#ifdef DEBUG
printk("Calling done function - at address %p\n", SCpnt->done);
#endif
host->host_busy--; /* Indicate that we are free */
device->device_busy--; /* Decrement device usage counter. */
SCpnt->result = result | ((exit & 0xff) << 24);
SCpnt->use_sg = SCpnt->old_use_sg;
SCpnt->cmd_len = SCpnt->old_cmd_len;
SCpnt->sc_data_direction = SCpnt->sc_old_data_direction;
SCpnt->underflow = SCpnt->old_underflow;
/*
* The upper layers assume the lock isn't held. We mustn't
* disappoint them. When the new error handling code is in
* use, the upper code is run from a bottom half handler, so
* it isn't an issue.
*/
spin_unlock_irq(&io_request_lock);
SRpnt = SCpnt->sc_request;
if( SRpnt != NULL ) {
SRpnt->sr_result = SRpnt->sr_command->result;
if( SRpnt->sr_result != 0 ) {
memcpy(SRpnt->sr_sense_buffer,
SRpnt->sr_command->sense_buffer,
sizeof(SRpnt->sr_sense_buffer));
}
}
SCpnt->done(SCpnt);
spin_lock_irq(&io_request_lock);
}
#undef CMD_FINISHED
#undef REDO
#undef MAYREDO
#undef PENDING
}
/*
* The scsi_abort function interfaces with the abort() function of the host
* we are aborting, and causes the current command to not complete. The
* caller should deal with any error messages or status returned on the
* next call.
*
* This will not be called reentrantly for a given host.
*/
/*
* Since we're nice guys and specified that abort() and reset()
* can be non-reentrant. The internal_timeout flags are used for
* this.
*/
static int scsi_abort(Scsi_Cmnd * SCpnt, int why)
{
int oldto;
struct Scsi_Host *host = SCpnt->host;
while (1) {
/*
* Protect against races here. If the command is done, or we are
* on a different command forget it.
*/
if (SCpnt->serial_number != SCpnt->serial_number_at_timeout) {
return 0;
}
if (SCpnt->internal_timeout & IN_ABORT) {
spin_unlock_irq(&io_request_lock);
while (SCpnt->internal_timeout & IN_ABORT)
barrier();
spin_lock_irq(&io_request_lock);
} else {
SCpnt->internal_timeout |= IN_ABORT;
oldto = update_timeout(SCpnt, ABORT_TIMEOUT);
if ((SCpnt->flags & IS_RESETTING) && SCpnt->device->soft_reset) {
/* OK, this command must have died when we did the
* reset. The device itself must have lied.
*/
printk("Stale command on %d %d:%d appears to have died when"
" the bus was reset\n",
SCpnt->channel, SCpnt->target, SCpnt->lun);
}
if (!host->host_busy) {
SCpnt->internal_timeout &= ~IN_ABORT;
update_timeout(SCpnt, oldto);
return 0;
}
printk("scsi : aborting command due to timeout : pid %lu, scsi%d,"
" channel %d, id %d, lun %d ",
SCpnt->pid, SCpnt->host->host_no, (int) SCpnt->channel,
(int) SCpnt->target, (int) SCpnt->lun);
print_command(SCpnt->cmnd);
if (SCpnt->serial_number != SCpnt->serial_number_at_timeout)
return 0;
SCpnt->abort_reason = why;
switch (host->hostt->abort(SCpnt)) {
/* We do not know how to abort. Try waiting another
* time increment and see if this helps. Set the
* WAS_TIMEDOUT flag set so we do not try this twice
*/
case SCSI_ABORT_BUSY: /* Tough call - returning 1 from
* this is too severe
*/
case SCSI_ABORT_SNOOZE:
if (why == DID_TIME_OUT) {
SCpnt->internal_timeout &= ~IN_ABORT;
if (SCpnt->flags & WAS_TIMEDOUT) {
return 1; /* Indicate we cannot handle this.
* We drop down into the reset handler
* and try again
*/
} else {
SCpnt->flags |= WAS_TIMEDOUT;
oldto = SCpnt->timeout_per_command;
update_timeout(SCpnt, oldto);
}
}
return 0;
case SCSI_ABORT_PENDING:
if (why != DID_TIME_OUT) {
update_timeout(SCpnt, oldto);
}
return 0;
case SCSI_ABORT_SUCCESS:
/* We should have already aborted this one. No
* need to adjust timeout
*/
SCpnt->internal_timeout &= ~IN_ABORT;
return 0;
case SCSI_ABORT_NOT_RUNNING:
SCpnt->internal_timeout &= ~IN_ABORT;
update_timeout(SCpnt, 0);
return 0;
case SCSI_ABORT_ERROR:
default:
SCpnt->internal_timeout &= ~IN_ABORT;
return 1;
}
}
}
}
/* Mark a single SCSI Device as having been reset. */
static inline void scsi_mark_device_reset(Scsi_Device * Device)
{
Device->was_reset = 1;
Device->expecting_cc_ua = 1;
}
/* Mark all SCSI Devices on a specific Host as having been reset. */
void scsi_mark_host_reset(struct Scsi_Host *Host)
{
Scsi_Cmnd *SCpnt;
Scsi_Device *SDpnt;
for (SDpnt = Host->host_queue; SDpnt; SDpnt = SDpnt->next) {
for (SCpnt = SDpnt->device_queue; SCpnt; SCpnt = SCpnt->next)
scsi_mark_device_reset(SCpnt->device);
}
}
/* Mark all SCSI Devices on a specific Host Bus as having been reset. */
static void scsi_mark_bus_reset(struct Scsi_Host *Host, int channel)
{
Scsi_Cmnd *SCpnt;
Scsi_Device *SDpnt;
for (SDpnt = Host->host_queue; SDpnt; SDpnt = SDpnt->next) {
for (SCpnt = SDpnt->device_queue; SCpnt; SCpnt = SCpnt->next)
if (SCpnt->channel == channel)
scsi_mark_device_reset(SCpnt->device);
}
}
static int scsi_reset(Scsi_Cmnd * SCpnt, unsigned int reset_flags)
{
int temp;
Scsi_Cmnd *SCpnt1;
Scsi_Device *SDpnt;
struct Scsi_Host *host = SCpnt->host;
printk("SCSI bus is being reset for host %d channel %d.\n",
host->host_no, SCpnt->channel);
#if 0
/*
* First of all, we need to make a recommendation to the low-level
* driver as to whether a BUS_DEVICE_RESET should be performed,
* or whether we should do a full BUS_RESET. There is no simple
* algorithm here - we basically use a series of heuristics
* to determine what we should do.
*/
SCpnt->host->suggest_bus_reset = FALSE;
/*
* First see if all of the active devices on the bus have
* been jammed up so that we are attempting resets. If so,
* then suggest a bus reset. Forcing a bus reset could
* result in some race conditions, but no more than
* you would usually get with timeouts. We will cross
* that bridge when we come to it.
*
* This is actually a pretty bad idea, since a sequence of
* commands will often timeout together and this will cause a
* Bus Device Reset followed immediately by a SCSI Bus Reset.
* If all of the active devices really are jammed up, the
* Bus Device Reset will quickly timeout and scsi_times_out
* will follow up with a SCSI Bus Reset anyway.
*/
SCpnt1 = host->host_queue;
while (SCpnt1) {
if (SCpnt1->request.rq_status != RQ_INACTIVE
&& (SCpnt1->flags & (WAS_RESET | IS_RESETTING)) == 0)
break;
SCpnt1 = SCpnt1->next;
}
if (SCpnt1 == NULL) {
reset_flags |= SCSI_RESET_SUGGEST_BUS_RESET;
}
/*
* If the code that called us is suggesting a hard reset, then
* definitely request it. This usually occurs because a
* BUS_DEVICE_RESET times out.
*
* Passing reset_flags along takes care of this automatically.
*/
if (reset_flags & SCSI_RESET_SUGGEST_BUS_RESET) {
SCpnt->host->suggest_bus_reset = TRUE;
}
#endif
while (1) {
/*
* Protect against races here. If the command is done, or we are
* on a different command forget it.
*/
if (reset_flags & SCSI_RESET_ASYNCHRONOUS)
if (SCpnt->serial_number != SCpnt->serial_number_at_timeout) {
return 0;
}
if (SCpnt->internal_timeout & IN_RESET) {
spin_unlock_irq(&io_request_lock);
while (SCpnt->internal_timeout & IN_RESET)
barrier();
spin_lock_irq(&io_request_lock);
} else {
SCpnt->internal_timeout |= IN_RESET;
update_timeout(SCpnt, RESET_TIMEOUT);
if (reset_flags & SCSI_RESET_SYNCHRONOUS)
SCpnt->flags |= SYNC_RESET;
if (host->host_busy) {
for (SDpnt = host->host_queue; SDpnt; SDpnt = SDpnt->next) {
SCpnt1 = SDpnt->device_queue;
while (SCpnt1) {
if (SCpnt1->request.rq_status != RQ_INACTIVE) {
#if 0
if (!(SCpnt1->flags & IS_RESETTING) &&
!(SCpnt1->internal_timeout & IN_ABORT))
scsi_abort(SCpnt1, DID_RESET);
#endif
SCpnt1->flags |= (WAS_RESET | IS_RESETTING);
}
SCpnt1 = SCpnt1->next;
}
}
host->last_reset = jiffies;
host->resetting = 1;
/*
* I suppose that the host reset callback will not play
* with the resetting field. We have just set the resetting
* flag here. -arca
*/
temp = host->hostt->reset(SCpnt, reset_flags);
/*
This test allows the driver to introduce an additional bus
settle time delay by setting last_reset up to 20 seconds in
the future. In the normal case where the driver does not
modify last_reset, it must be assumed that the actual bus
reset occurred immediately prior to the return to this code,
and so last_reset must be updated to the current time, so
that the delay in internal_cmnd will guarantee at least a
MIN_RESET_DELAY bus settle time.
*/
if (host->last_reset - jiffies > 20UL * HZ)
host->last_reset = jiffies;
} else {
host->host_busy++;
host->last_reset = jiffies;
host->resetting = 1;
SCpnt->flags |= (WAS_RESET | IS_RESETTING);
/*
* I suppose that the host reset callback will not play
* with the resetting field. We have just set the resetting
* flag here. -arca
*/
temp = host->hostt->reset(SCpnt, reset_flags);
if (time_before(host->last_reset, jiffies) ||
(time_after(host->last_reset, jiffies + 20 * HZ)))
host->last_reset = jiffies;
host->host_busy--;
}
if (reset_flags & SCSI_RESET_SYNCHRONOUS)
SCpnt->flags &= ~SYNC_RESET;
#ifdef DEBUG
printk("scsi reset function returned %d\n", temp);
#endif
/*
* Now figure out what we need to do, based upon
* what the low level driver said that it did.
* If the result is SCSI_RESET_SUCCESS, SCSI_RESET_PENDING,
* or SCSI_RESET_WAKEUP, then the low level driver did a
* bus device reset or bus reset, so we should go through
* and mark one or all of the devices on that bus
* as having been reset.
*/
switch (temp & SCSI_RESET_ACTION) {
case SCSI_RESET_SUCCESS:
if (temp & SCSI_RESET_HOST_RESET)
scsi_mark_host_reset(host);
else if (temp & SCSI_RESET_BUS_RESET)
scsi_mark_bus_reset(host, SCpnt->channel);
else
scsi_mark_device_reset(SCpnt->device);
SCpnt->internal_timeout &= ~(IN_RESET | IN_RESET2 | IN_RESET3);
return 0;
case SCSI_RESET_PENDING:
if (temp & SCSI_RESET_HOST_RESET)
scsi_mark_host_reset(host);
else if (temp & SCSI_RESET_BUS_RESET)
scsi_mark_bus_reset(host, SCpnt->channel);
else
scsi_mark_device_reset(SCpnt->device);
case SCSI_RESET_NOT_RUNNING:
return 0;
case SCSI_RESET_PUNT:
SCpnt->internal_timeout &= ~(IN_RESET | IN_RESET2 | IN_RESET3);
scsi_request_sense(SCpnt);
return 0;
case SCSI_RESET_WAKEUP:
if (temp & SCSI_RESET_HOST_RESET)
scsi_mark_host_reset(host);
else if (temp & SCSI_RESET_BUS_RESET)
scsi_mark_bus_reset(host, SCpnt->channel);
else
scsi_mark_device_reset(SCpnt->device);
SCpnt->internal_timeout &= ~(IN_RESET | IN_RESET2 | IN_RESET3);
scsi_request_sense(SCpnt);
/*
* If a bus reset was performed, we
* need to wake up each and every command
* that was active on the bus or if it was a HBA
* reset all active commands on all channels
*/
if (temp & SCSI_RESET_HOST_RESET) {
for (SDpnt = host->host_queue; SDpnt; SDpnt = SDpnt->next) {
SCpnt1 = SDpnt->device_queue;
while (SCpnt1) {
if (SCpnt1->request.rq_status != RQ_INACTIVE
&& SCpnt1 != SCpnt)
scsi_request_sense(SCpnt1);
SCpnt1 = SCpnt1->next;
}
}
} else if (temp & SCSI_RESET_BUS_RESET) {
for (SDpnt = host->host_queue; SDpnt; SDpnt = SDpnt->next) {
SCpnt1 = SDpnt->device_queue;
while (SCpnt1) {
if (SCpnt1->request.rq_status != RQ_INACTIVE
&& SCpnt1 != SCpnt
&& SCpnt1->channel == SCpnt->channel)
scsi_request_sense(SCpnt);
SCpnt1 = SCpnt1->next;
}
}
}
return 0;
case SCSI_RESET_SNOOZE:
/* In this case, we set the timeout field to 0
* so that this command does not time out any more,
* and we return 1 so that we get a message on the
* screen.
*/
SCpnt->internal_timeout &= ~(IN_RESET | IN_RESET2 | IN_RESET3);
update_timeout(SCpnt, 0);
/* If you snooze, you lose... */
case SCSI_RESET_ERROR:
default:
return 1;
}
return temp;
}
}
}
/*
* The strategy is to cause the timer code to call scsi_times_out()
* when the soonest timeout is pending.
* The arguments are used when we are queueing a new command, because
* we do not want to subtract the time used from this time, but when we
* set the timer, we want to take this value into account.
*/
int update_timeout(Scsi_Cmnd * SCset, int timeout)
{
int rtn;
/*
* We are using the new error handling code to actually register/deregister
* timers for timeout.
*/
if (!timer_pending(&SCset->eh_timeout)) {
rtn = 0;
} else {
rtn = SCset->eh_timeout.expires - jiffies;
}
if (timeout == 0) {
scsi_delete_timer(SCset);
} else {
scsi_add_timer(SCset, timeout, scsi_old_times_out);
}
return rtn;
}
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-indent-level: 4
* c-brace-imaginary-offset: 0
* c-brace-offset: -4
* c-argdecl-indent: 4
* c-label-offset: -4
* c-continued-statement-offset: 4
* c-continued-brace-offset: 0
* indent-tabs-mode: nil
* tab-width: 8
* End:
*/
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