3w-xxxx.c

讲述linux的初始化过程

		/* Empty the response queue again */
		error = tw_empty_response_que(tw_dev);
		if (error) {
			printk(KERN_WARNING "3w-xxxx: tw_reset_sequence(): Couldn't empty response queue for card %d.\n", tw_dev->host->host_no);
			tries++;
			continue;
		}

		/* Now the controller is in a good state */
		break;
	}

	if (tries >= TW_MAX_RESET_TRIES) {
		printk(KERN_WARNING "3w-xxxx: tw_reset_sequence(): Controller error or no attention interrupt: giving up for card %d.\n", tw_dev->host->host_no);
		return 1;
	}

	error = tw_initconnection(tw_dev, TW_INIT_MESSAGE_CREDITS);
	if (error) {
		printk(KERN_WARNING "3w-xxxx: tw_reset_sequence(): Couldn't initconnection for card %d.\n", tw_dev->host->host_no);
		return 1;
	}

	/* Re-enable interrupts */
	tw_enable_interrupts(tw_dev);

	return 0;
} /* End tw_reset_sequence() */

/* This funciton returns unit geometry in cylinders/heads/sectors */
int tw_scsi_biosparam(Disk *disk, kdev_t dev, int geom[]) 
{
	int heads, sectors, cylinders;
	TW_Device_Extension *tw_dev;
	
	dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_biosparam()\n");
	tw_dev = (TW_Device_Extension *)disk->device->host->hostdata;

	heads = 64;
	sectors = 32;
	cylinders = disk->capacity / (heads * sectors);

	if (disk->capacity >= 0x200000) {
		heads = 255;
		sectors = 63;
		cylinders = disk->capacity / (heads * sectors);
	}

	dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_biosparam(): heads = %d, sectors = %d, cylinders = %d\n", heads, sectors, cylinders);
	geom[0] = heads;			 
	geom[1] = sectors;
	geom[2] = cylinders;

	return 0;
} /* End tw_scsi_biosparam() */

/* This function will find and initialize any cards */
int tw_scsi_detect(Scsi_Host_Template *tw_host)
{
	dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_detect()\n");

	/* Check if the kernel has PCI interface compiled in */
	if (!pci_present()) {
		printk(KERN_WARNING "3w-xxxx: tw_scsi_detect(): No pci interface present.\n");
		return 0;
	}

	return(tw_findcards(tw_host));
} /* End tw_scsi_detect() */

/* This is the new scsi eh abort function */
int tw_scsi_eh_abort(Scsi_Cmnd *SCpnt) 
{
	TW_Device_Extension *tw_dev=NULL;
	int i = 0;

	dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_eh_abort()\n");

	if (!SCpnt) {
		printk(KERN_WARNING "3w-xxxx: tw_scsi_eh_abort(): Invalid Scsi_Cmnd.\n");
		return (FAILED);
	}

	tw_dev = (TW_Device_Extension *)SCpnt->host->hostdata;
	if (tw_dev == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_scsi_eh_abort(): Invalid device extension.\n");
		return (FAILED);
	}

	spin_lock(&tw_dev->tw_lock);
	tw_dev->num_aborts++;

	/* If the command hasn't been posted yet, we can do the abort */
	for (i=0;i<TW_Q_LENGTH;i++) {
		if (tw_dev->srb[i] == SCpnt) {
			if (tw_dev->state[i] == TW_S_STARTED) {
				printk(KERN_WARNING "3w-xxxx: tw_scsi_eh_abort(): Abort succeeded for started Scsi_Cmnd 0x%x\n", (u32)tw_dev->srb[i]);
				tw_dev->state[i] = TW_S_COMPLETED;
				tw_state_request_finish(tw_dev, i);
				spin_unlock(&tw_dev->tw_lock);
				return (SUCCESS);
			}
			if (tw_dev->state[i] == TW_S_PENDING) {
				printk(KERN_WARNING "3w-xxxx: tw_scsi_eh_abort(): Abort succeeded for pending Scsi_Cmnd 0x%x\n", (u32)tw_dev->srb[i]);
				if (tw_dev->pending_head == TW_Q_LENGTH-1) {
					tw_dev->pending_head = TW_Q_START;
				} else {
					tw_dev->pending_head = tw_dev->pending_head + 1;
				}
				tw_dev->pending_request_count--;
				tw_dev->state[i] = TW_S_COMPLETED;
				tw_state_request_finish(tw_dev, i);
				spin_unlock(&tw_dev->tw_lock);
				return (SUCCESS);
			}
		}
	}

	/* If the command has already been posted, we have to reset the card */
	printk(KERN_WARNING "3w-xxxx: tw_scsi_eh_abort(): Abort failed for unknown Scsi_Cmnd 0x%x, resetting card %d.\n", (u32)SCpnt, tw_dev->host->host_no);

	if (tw_reset_device_extension(tw_dev)) {
		printk(KERN_WARNING "3w-xxxx: tw_scsi_eh_abort(): Reset failed for card %d.\n", tw_dev->host->host_no);
		spin_unlock(&tw_dev->tw_lock);
		return (FAILED);
	}
	spin_unlock(&tw_dev->tw_lock);

	return (SUCCESS);
} /* End tw_scsi_eh_abort() */

/* This is the new scsi eh reset function */
int tw_scsi_eh_reset(Scsi_Cmnd *SCpnt) 
{
	TW_Device_Extension *tw_dev=NULL;

	dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_eh_reset()\n");

	if (!SCpnt) {
		printk(KERN_WARNING "3w-xxxx: tw_scsi_eh_reset(): Invalid Scsi_Cmnd.\n");
		return (FAILED);
	}

	tw_dev = (TW_Device_Extension *)SCpnt->host->hostdata;
	if (tw_dev == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_scsi_eh_reset(): Invalid device extension.\n");
		return (FAILED);
	}

	spin_lock(&tw_dev->tw_lock);
	tw_dev->num_resets++;

	/* Now reset the card and some of the device extension data */
	if (tw_reset_device_extension(tw_dev)) {
		printk(KERN_WARNING "3w-xxxx: tw_scsi_eh_reset(): Reset failed for card %d.\n", tw_dev->host->host_no);
		spin_unlock(&tw_dev->tw_lock);
		return (FAILED);
	}
	printk(KERN_WARNING "3w-xxxx: tw_scsi_eh_reset(): Reset succeeded for card %d.\n", tw_dev->host->host_no);
	spin_unlock(&tw_dev->tw_lock);

	return (SUCCESS);
} /* End tw_scsi_eh_reset() */

/* This function handles input and output from /proc/scsi/3w-xxxx/x */
int tw_scsi_proc_info(char *buffer, char **start, off_t offset, int length, int hostno, int inout) 
{
	TW_Device_Extension *tw_dev = NULL;
	TW_Info info;
	int i;
	int j;

	dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_proc_info()\n");

	/* Find the correct device extension */
	for (i=0;i<tw_device_extension_count;i++) 
		if (tw_device_extension_list[i]->host->host_no == hostno) 
			tw_dev = tw_device_extension_list[i];
	if (tw_dev == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_scsi_proc_info(): Couldn't locate device extension.\n");
		return (-EINVAL);
	}

	info.buffer = buffer;
	info.length = length;
	info.offset = offset;
	info.position = 0;
	
	if (inout) {
		/* Write */
		if (strncmp(buffer, "debug", 5) == 0) {
			printk(KERN_INFO "3w-xxxx: Posted commands:\n");
			for (j=0;j<TW_Q_LENGTH;j++) {
				if (tw_dev->state[j] == TW_S_POSTED) {
					TW_Command *command = (TW_Command *)tw_dev->command_packet_virtual_address[j];
					printk(KERN_INFO "3w-xxxx: Request_id: %d\n", j);
					printk(KERN_INFO "Opcode: 0x%x\n", command->byte0.opcode);
					printk(KERN_INFO "Block_count: 0x%x\n", command->byte6.block_count);
					printk(KERN_INFO "LBA: 0x%x\n", (u32)command->byte8.io.lba);
					printk(KERN_INFO "Physical command packet addr: 0x%x\n", tw_dev->command_packet_physical_address[j]);
					printk(KERN_INFO "Scsi_Cmnd: 0x%x\n", (u32)tw_dev->srb[j]);
				}
			}
			printk(KERN_INFO "3w-xxxx: Free_head: %3d\n", tw_dev->free_head);
			printk(KERN_INFO "3w-xxxx: Free_tail: %3d\n", tw_dev->free_tail);
		} 
		return length;
	} else {
		/* Read */
		if (start) {
			*start = buffer;
		}
		tw_copy_info(&info, "scsi%d: 3ware Storage Controller\n", hostno);
		tw_copy_info(&info, "Driver version: %s\n", tw_driver_version);
		tw_copy_info(&info, "Current commands posted:       %3d\n", tw_dev->posted_request_count);
		tw_copy_info(&info, "Max commands posted:           %3d\n", tw_dev->max_posted_request_count);
		tw_copy_info(&info, "Current pending commands:      %3d\n", tw_dev->pending_request_count);
		tw_copy_info(&info, "Max pending commands:          %3d\n", tw_dev->max_pending_request_count);
		tw_copy_info(&info, "Last sgl length:               %3d\n", tw_dev->sgl_entries);
		tw_copy_info(&info, "Max sgl length:                %3d\n", tw_dev->max_sgl_entries);
		tw_copy_info(&info, "Last sector count:             %3d\n", tw_dev->sector_count);
		tw_copy_info(&info, "Max sector count:              %3d\n", tw_dev->max_sector_count);
		tw_copy_info(&info, "Resets:                        %3d\n", tw_dev->num_resets);
		tw_copy_info(&info, "Aborts:                        %3d\n", tw_dev->num_aborts);
	}
	if (info.position > info.offset) {
		return (info.position - info.offset);
	} else { 
		return 0;
	}
} /* End tw_scsi_proc_info() */

/* This is the main scsi queue function to handle scsi opcodes */
int tw_scsi_queue(Scsi_Cmnd *SCpnt, void (*done)(Scsi_Cmnd *)) 
{
	unsigned char *command = SCpnt->cmnd;
	int request_id = 0;
	int error = 0;
	int flags = 0;
	TW_Device_Extension *tw_dev = (TW_Device_Extension *)SCpnt->host->hostdata;

	spin_lock_irqsave(&tw_dev->tw_lock, flags);
	dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_queue()\n");

	/* Skip scsi command if it isn't for us */
	if ((tw_dev->is_unit_present[SCpnt->target] == FALSE) || (SCpnt->lun != 0)) {
		SCpnt->result = (DID_BAD_TARGET << 16);
		done(SCpnt);
		spin_unlock_irqrestore(&tw_dev->tw_lock, flags);
		return 0;
	}
	if (done == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_scsi_queue(): Invalid done function.\n");
		SCpnt->result = (DID_ERROR << 16);
		done(SCpnt);
		spin_unlock_irqrestore(&tw_dev->tw_lock, flags);
		return 0;
	}
	if (tw_dev == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_scsi_queue(): Invalid device extension.\n");
		SCpnt->result = (DID_ERROR << 16);
		done(SCpnt);
		spin_unlock_irqrestore(&tw_dev->tw_lock, flags);
		return 0;
	}
	
	/* Save done function into Scsi_Cmnd struct */
	SCpnt->scsi_done = done;
		 
	/* Queue the command and get a request id */
	tw_state_request_start(tw_dev, &request_id);

	/* Save the scsi command for use by the ISR */
	tw_dev->srb[request_id] = SCpnt;

	switch (*command) {
		case READ_10:
			dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_queue(): caught READ_10.\n");
		case READ_6:
			dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_queue(): caught READ_6.\n");
		case WRITE_10:
			dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_queue(): caught WRITE_10.\n");
		case WRITE_6:
			dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_queue(): caught WRITE_6.\n");
			error = tw_scsiop_read_write(tw_dev, request_id);
			break;
		case TEST_UNIT_READY:
			dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_queue(): caught TEST_UNIT_READY.\n");
			error = tw_scsiop_test_unit_ready(tw_dev, request_id);
			break;
		case INQUIRY:
			dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_queue(): caught INQUIRY.\n");
			error = tw_scsiop_inquiry(tw_dev, request_id);
			break;
		case READ_CAPACITY:
			dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_queue(): caught READ_CAPACITY.\n");
			error = tw_scsiop_read_capacity(tw_dev, request_id);
			break;
		case TW_IOCTL:
			dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_queue(): caught TW_SCSI_IOCTL.\n");
			error = tw_ioctl(tw_dev, request_id);
			break;
		default:
			printk(KERN_NOTICE "3w-xxxx: tw_scsi_queue(): Unknown scsi opcode: 0x%x\n", *command);
			tw_dev->state[request_id] = TW_S_COMPLETED;
			tw_state_request_finish(tw_dev, request_id);
			SCpnt->result = (DID_BAD_TARGET << 16);
			done(SCpnt);
	}
	if (error) {
		tw_dev->state[request_id] = TW_S_COMPLETED;
		tw_state_request_finish(tw_dev, request_id);
		SCpnt->result = (DID_ERROR << 16);
		done(SCpnt);
	}
	spin_unlock_irqrestore(&tw_dev->tw_lock, flags);

	return 0;
} /* End tw_scsi_queue() */

/* This function will release the resources on an rmmod call */
int tw_scsi_release(struct Scsi_Host *tw_host) 
{
	TW_Device_Extension *tw_dev;
	tw_dev = (TW_Device_Extension *)tw_host->hostdata;

	dprintk(KERN_NOTICE "3w-xxxx: tw_scsi_release()\n");

	/* Free up the IO region */
	release_region((tw_dev->tw_pci_dev->resource[0].start), TW_IO_ADDRESS_RANGE);

	/* Free up the IRQ */
	free_irq(tw_dev->tw_pci_dev->irq, tw_dev);

	/* Free up device extension resources */
	tw_free_device_extension(tw_dev);

	/* Tell kernel scsi-layer we are gone */
	scsi_unregister(tw_host);
	
	/* Fake like we just shut down, so notify the card that
	 * we "shut down cleanly".
	 */
	tw_halt(0, 0, 0);  // parameters aren't actually used

	return 0;
} /* End tw_scsi_release() */

/* This function handles scsi inquiry commands */
int tw_scsiop_inquiry(TW_Device_Extension *tw_dev, int request_id)
{
	TW_Param *param;
	TW_Command *command_packet;
	u32 command_que_value, command_que_addr;
	u32 param_value;

	dprintk(KERN_NOTICE "3w-xxxx: tw_scsiop_inquiry()\n");

	/* Initialize command packet */
	command_que_addr = tw_dev->registers.command_que_addr;
	command_packet = (TW_Command *)tw_dev->command_packet_virtual_address[request_id];
	if (command_packet == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_scsiop_inquiry(): Bad command packet virtual address.\n");
		return 1;
	}
	memset(command_packet, 0, sizeof(TW_Sector));
	command_packet->byte0.opcode = TW_OP_GET_PARAM;
	command_packet->byte0.sgl_offset = 2;
	command_packet->size = 4;
	command_packet->request_id = request_id;
	command_packet->byte3.unit = 0;
	command_packet->byte3.host_id = 0;
	command_packet->status = 0;
	command_packet->flags = 0;
	command_packet->byte6.parameter_count = 1;

	/* Now setup the param */
	if (tw_dev->alignment_virtual_address[request_id] == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_scsiop_in