patch-2.1.75 linux/drivers/scsi/scsi_obsolete.c
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- Lines: 1132
- Date:
Sun Dec 21 17:53:17 1997
- Orig file:
v2.1.74/linux/drivers/scsi/scsi_obsolete.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.1.74/linux/drivers/scsi/scsi_obsolete.c linux/drivers/scsi/scsi_obsolete.c
@@ -0,0 +1,1131 @@
+/*
+ * scsi.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@aib.com 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>
+ *
+ * Added request_module("scsi_hostadapter") for kerneld:
+ * (Put an "alias scsi_hostadapter your_hostadapter" in /etc/conf.modules)
+ * Bjorn Ekwall <bj0rn@blox.se>
+ *
+ * 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>
+ */
+
+/*
+ *#########################################################################
+ *#########################################################################
+ *#########################################################################
+ *#########################################################################
+ * 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/malloc.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"
+
+#ifdef CONFIG_KERNELD
+#include <linux/kerneld.h>
+#endif
+
+#undef USE_STATIC_SCSI_MEMORY
+
+/*
+static const char RCSid[] = "$Header: /mnt/ide/home/eric/linux/drivers/scsi/RCS/scsi_obsolete.c,v 1.3 1997/04/29 04:25:08 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);
+static int update_timeout (Scsi_Cmnd *, int);
+extern void scsi_old_times_out (Scsi_Cmnd * SCpnt);
+extern void internal_cmnd (Scsi_Cmnd * SCpnt);
+
+static volatile struct Scsi_Host * host_active = NULL;
+#define SCSI_BLOCK(HOST) ((HOST->block && host_active && HOST != host_active) \
+ || (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 NORMAL_TIMEOUT 0
+#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)
+{
+
+ 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))
+ return;
+ 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))
+ return;
+ 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);
+ return;
+ case (IN_ABORT | IN_RESET | 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);
+ return;
+
+ 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");
+ return;
+
+ }
+
+}
+
+
+static void scsi_request_sense (Scsi_Cmnd * SCpnt)
+{
+ unsigned long flags;
+
+ save_flags(flags);
+ cli();
+ SCpnt->flags |= WAS_SENSE | ASKED_FOR_SENSE;
+ update_timeout(SCpnt, SENSE_TIMEOUT);
+ restore_flags(flags);
+
+
+ memcpy ((void *) SCpnt->cmnd , (void *) generic_sense,
+ sizeof(generic_sense));
+
+ 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]);
+ internal_cmnd (SCpnt);
+}
+
+
+
+
+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;
+ int result = SCpnt->result;
+ SCpnt->serial_number = 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 & WAS_SENSE)
+ {
+ SCpnt->use_sg = SCpnt->old_use_sg;
+ SCpnt->cmd_len = SCpnt->old_cmd_len;
+ }
+
+ 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);
+ return;
+ }
+ 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);
+ return;
+#if 0
+ exit = DRIVER_SOFT | SUGGEST_ABORT;
+ status = MAYREDO;
+ break;
+#endif
+ 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->last_reset > 0 &&
+ 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);
+ break;
+ }
+
+ }
+ 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));
+ SCpnt->request_buffer = SCpnt->buffer;
+ SCpnt->request_bufflen = SCpnt->bufflen;
+ SCpnt->use_sg = SCpnt->old_use_sg;
+ SCpnt->cmd_len = SCpnt->old_cmd_len;
+ internal_cmnd (SCpnt);
+ }
+ break;
+ default:
+ INTERNAL_ERROR;
+ }
+
+ if (status == CMD_FINISHED) {
+#ifdef DEBUG
+ printk("Calling done function - at address %p\n", SCpnt->done);
+#endif
+ host->host_busy--; /* Indicate that we are free */
+
+ if (host->block && host->host_busy == 0) {
+ host_active = NULL;
+
+ /* For block devices "wake_up" is done in end_scsi_request */
+ if (MAJOR(SCpnt->request.rq_dev) != SCSI_DISK_MAJOR &&
+ MAJOR(SCpnt->request.rq_dev) != SCSI_CDROM_MAJOR) {
+ struct Scsi_Host * next;
+
+ for (next = host->block; next != host; next = next->block)
+ wake_up(&next->host_wait);
+ }
+
+ }
+
+ wake_up(&host->host_wait);
+ SCpnt->result = result | ((exit & 0xff) << 24);
+ SCpnt->use_sg = SCpnt->old_use_sg;
+ SCpnt->cmd_len = SCpnt->old_cmd_len;
+ SCpnt->done (SCpnt);
+ }
+
+#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;
+ unsigned long flags;
+ struct Scsi_Host * host = SCpnt->host;
+
+ while(1)
+ {
+ save_flags(flags);
+ cli();
+
+ /*
+ * 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) {
+ restore_flags(flags);
+ return 0;
+ }
+
+ if (SCpnt->internal_timeout & IN_ABORT)
+ {
+ restore_flags(flags);
+ while (SCpnt->internal_timeout & IN_ABORT)
+ barrier();
+ }
+ 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);
+ }
+
+ restore_flags(flags);
+ 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) {
+ save_flags(flags);
+ cli();
+ SCpnt->internal_timeout &= ~IN_ABORT;
+ if(SCpnt->flags & WAS_TIMEDOUT) {
+ restore_flags(flags);
+ 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);
+ }
+ restore_flags(flags);
+ }
+ return 0;
+ case SCSI_ABORT_PENDING:
+ if(why != DID_TIME_OUT) {
+ save_flags(flags);
+ cli();
+ update_timeout(SCpnt, oldto);
+ restore_flags(flags);
+ }
+ 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;
+ unsigned long flags;
+ 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) {
+ save_flags(flags);
+ cli();
+
+ /*
+ * 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) {
+ restore_flags(flags);
+ return 0;
+ }
+
+ if (SCpnt->internal_timeout & IN_RESET)
+ {
+ restore_flags(flags);
+ while (SCpnt->internal_timeout & IN_RESET)
+ barrier();
+ }
+ else
+ {
+ SCpnt->internal_timeout |= IN_RESET;
+ update_timeout(SCpnt, RESET_TIMEOUT);
+
+ if (host->host_busy)
+ {
+ restore_flags(flags);
+ 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;
+ 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
+ {
+ if (!host->block) host->host_busy++;
+ restore_flags(flags);
+ host->last_reset = jiffies;
+ SCpnt->flags |= (WAS_RESET | IS_RESETTING);
+ temp = host->hostt->reset(SCpnt, reset_flags);
+ if ((host->last_reset < jiffies) ||
+ (host->last_reset > (jiffies + 20 * HZ)))
+ host->last_reset = jiffies;
+ if (!host->block) host->host_busy--;
+ }
+
+#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);
+ save_flags(flags);
+ cli();
+ SCpnt->internal_timeout &= ~(IN_RESET|IN_RESET2|IN_RESET3);
+ restore_flags(flags);
+ 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.
+ */
+ save_flags(flags);
+ cli();
+ SCpnt->internal_timeout &= ~(IN_RESET|IN_RESET2|IN_RESET3);
+ update_timeout(SCpnt, 0);
+ restore_flags(flags);
+ /* 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.
+ */
+
+static 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( SCset->eh_timeout.expires == 0 )
+ {
+ 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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