/* * 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 * * * * Bug correction thanks go to : * Rik Faith * Tommy Thorn * Thomas Wuensche * * 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 * * Major improvements to the timeout, abort, and reset processing, * as well as performance modifications for large queue depths by * Leonard N. Zubkoff * * Improved compatibility with 2.0 behaviour by Manfred Spraul * */ /* *######################################################################### *######################################################################### *######################################################################### *######################################################################### * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #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)); 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 syncronous 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; } 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->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; /* * 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: */