// scsi tapset
// Copyright (C) 2005, 2006, 2009 IBM Corp.
// Copyright (C) 2014 Red Hat
//
// This file is part of systemtap, and is free software.  You can
// redistribute it and/or modify it under the terms of the GNU General
// Public License (GPL); either version 2, or (at your option) any
// later version.
// <tapsetdescription>
// This family of probe points is used to probe SCSI activities.
// </tapsetdescription>
%{
#include <linux/types.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include "linux/timer_compatibility.h"
#include <linux/blkdev.h>
%}

function describe_data_direction:string(state:long)
%{ /* pure */
	switch ((long)STAP_ARG_state) {
		case DMA_BIDIRECTIONAL:  strlcpy(STAP_RETVALUE, "BIDIRECTIONAL", MAXSTRINGLEN); break;
		case DMA_TO_DEVICE:      strlcpy(STAP_RETVALUE, "TO_DEVICE",     MAXSTRINGLEN); break;
		case DMA_FROM_DEVICE:    strlcpy(STAP_RETVALUE, "FROM_DEVICE",   MAXSTRINGLEN); break;
		case DMA_NONE:           strlcpy(STAP_RETVALUE, "NONE",          MAXSTRINGLEN); break;
		default:                 strlcpy(STAP_RETVALUE, "[INVALID]",     MAXSTRINGLEN);
	}
%}

function describe_device_state:string(state:long)
%{ /* pure */
	switch ((long)STAP_ARG_state) {
		case SDEV_CREATED:       strlcpy(STAP_RETVALUE, "CREATED",       MAXSTRINGLEN); break;
		case SDEV_RUNNING:       strlcpy(STAP_RETVALUE, "RUNNING",       MAXSTRINGLEN); break;
		case SDEV_CANCEL:        strlcpy(STAP_RETVALUE, "CANCEL",        MAXSTRINGLEN); break;
		case SDEV_DEL:           strlcpy(STAP_RETVALUE, "DEL",           MAXSTRINGLEN); break;
		case SDEV_QUIESCE:       strlcpy(STAP_RETVALUE, "QUIESCE",       MAXSTRINGLEN); break;
		case SDEV_OFFLINE:       strlcpy(STAP_RETVALUE, "OFFLINE",       MAXSTRINGLEN); break;
#ifdef SDEV_BLOCK
		case SDEV_BLOCK:         strlcpy(STAP_RETVALUE, "BLOCK",         MAXSTRINGLEN); break;
#endif
#ifdef SDEV_CREATED_BLOCK
		case SDEV_CREATED_BLOCK: strlcpy(STAP_RETVALUE, "CREATED_BLOCK", MAXSTRINGLEN); break;
#endif
		default:                 strlcpy(STAP_RETVALUE, "[INVALID]",     MAXSTRINGLEN);
	}
%}
/**
  * probe scsi.ioentry - Prepares a SCSI mid-layer request
  * @disk_major: The major number of the disk (-1 if no information)
  * @disk_minor: The minor number of the disk (-1 if no information)
  * @device_state: The current state of the device
  * @device_state_str: The current state of the device, as a string
  * @req_addr: The current struct request pointer, as a number
  */
probe scsi.ioentry.scsilib =
      module("scsi_mod").function("scsi_prep_fn")!, kernel.function("scsi_prep_fn")? { }
probe scsi.ioentry.sd =
      module("sd_mod").function("sd_prep_fn")!, kernel.function("sd_prep_fn")? { }
probe scsi.ioentry.sr =
      module("sr_mod").function("sr_prep_fn")!, kernel.function("sr_prep_fn")? { }

probe scsi.ioentry = scsi.ioentry.* ?
{
        req_addr = @choose_defined($req, $rq);
	if(@cast(req_addr,"request")->rq_disk == 0)  {
		disk_major = -1
		disk_minor = -1
	} else {
		disk_major = @cast(req_addr,"request")->rq_disk->major
		disk_minor = @cast(req_addr,"request")->rq_disk->first_minor
	}
	device_state = get_devstate_from_req($q)
	device_state_str = describe_device_state(device_state)
}

/**
 * probe scsi.iodispatching - SCSI mid-layer dispatched low-level SCSI command
 * @host_no: The host number
 * @channel: The channel number
 * @lun: The lun number
 * @dev_id: The scsi device id
 * @device_state: The current state of the device
 * @device_state_str: The current state of the device, as a string
 * @data_direction: The data_direction specifies whether this command is from/to the device
 *		0 (DMA_BIDIRECTIONAL), 1 (DMA_TO_DEVICE),
 *		2 (DMA_FROM_DEVICE), 3 (DMA_NONE)
 * @data_direction_str: Data direction, as a string
 * @request_buffer: The request buffer address
 * @request_bufflen: The request buffer length
 * @req_addr: The current struct request pointer, as a number
 */
probe scsi.iodispatching
	= module("scsi_mod").function("scsi_dispatch_cmd")!,
	  kernel.function("scsi_dispatch_cmd")?
{
	host_no = $cmd->device->host->host_no
	channel = $cmd->device->channel
	lun = $cmd->device->lun
	dev_id = $cmd->device->id
	device_state = $cmd->device->sdev_state
	device_state_str = describe_device_state(device_state)
	data_direction = $cmd->sc_data_direction
	data_direction_str = describe_data_direction(data_direction)
	request_buffer = @choose_defined($cmd->sdb->table->sgl,
					 $cmd->request_buffer)
	request_bufflen = @choose_defined($cmd->sdb->length,
					  $cmd->request_bufflen)
	req_addr = $cmd->request
}

/**
 * probe scsi.iodone - SCSI command completed by low level driver and enqueued into the done queue.
 * @host_no: The host number
 * @channel: The channel number
 * @lun: The lun number
 * @dev_id: The scsi device id
 * @device_state: The current state of the device
 * @device_state_str: The current state of the device, as a string
 * @data_direction: The data_direction specifies whether this command is
 * 		from/to the device.
 * @data_direction_str: Data direction, as a string
 * @req_addr: The current struct request pointer, as a number
 * @scsi_timer_pending: 1 if a timer is pending on this request
 */
probe scsi.iodone
	= kernel.trace("scsi_dispatch_cmd_done")!,
	  module("scsi_mod").function("scsi_done")!,
	  kernel.function("scsi_done")?

{
	# Why is the @cast() needed here? When the probe alias uses
	# the "scsi_dispatch_cmd_done" tracepoint, the type info isn't
	# in scope. 
	host_no = @cast($cmd->device, "scsi_device", "kernel:scsi_mod")->host->host_no
	channel = @cast($cmd->device, "scsi_device", "kernel:scsi_mod")->channel
	lun = @cast($cmd->device, "scsi_device", "kernel:scsi_mod")->lun
	dev_id = @cast($cmd->device, "scsi_device", "kernel:scsi_mod")->id
	device_state = @cast($cmd->device, "scsi_device", "kernel:scsi_mod")->sdev_state
	device_state_str = describe_device_state(device_state)
	data_direction = $cmd->sc_data_direction
	data_direction_str = describe_data_direction(data_direction)
	req_addr = $cmd->request
	scsi_timer_pending = scsi_timer_pending($cmd);
}

/**
 * probe scsi.iocompleted - SCSI mid-layer running the completion processing for block device I/O requests
 * @host_no: The host number
 * @channel: The channel number
 * @lun: The lun number
 * @dev_id: The scsi device id
 * @device_state: The current state of the device
 * @device_state_str: The current state of the device, as a string
 * @data_direction: The data_direction specifies whether this command is from/to
 * 		the device
 * @data_direction_str: Data direction, as a string
 * @goodbytes: The bytes completed
 * @req_addr: The current struct request pointer, as a number
 */
// mid-layer processes the completed IO
probe scsi.iocompleted
	= module("scsi_mod").function("scsi_io_completion")!,
	  kernel.function("scsi_io_completion")?
{
	host_no = $cmd->device->host->host_no
	channel = $cmd->device->channel
	lun = $cmd->device->lun
	dev_id = $cmd->device->id
	device_state = $cmd->device->sdev_state
	device_state_str = describe_device_state(device_state)
	data_direction = $cmd->sc_data_direction
	data_direction_str = describe_data_direction(data_direction)
	req_addr = $cmd->request
	goodbytes = $good_bytes
}

function timer_pending:long(timer:long)
{
	return (@choose_defined(@cast(timer, "timer_list")->entry->next,
				@cast(timer, "timer_list")->base) != 0)
}

function scsi_timer_pending:long(cmd:long)
{
%( kernel_v >= "2.6.28" %?
	return timer_pending(&@cast(cmd, "scsi_cmnd", "kernel:scsi_mod")->request->q->timeout)
%:
	return timer_pending(&@cast(cmd, "scsi_cmnd", "kernel:scsi_mod")->eh_timeout)
%)
}

function get_devstate_from_req:long(var:long)
{
	sdev = @cast(var, "request_queue", "kernel:scsi_mod")->queuedata
	return @cast(sdev, "scsi_device", "kernel:scsi_mod")->sdev_state
}

/**
 * probe scsi.ioexecute - Create mid-layer SCSI request and wait for the result
 * @host_no: The host number
 * @channel: The channel number
 * @lun: The lun number
 * @dev_id: The scsi device id
 * @device_state: The current state of the device
 * @device_state_str: The current state of the device, as a string
 * @data_direction: The data_direction specifies whether this command is
 * 		from/to the device.
 * @data_direction_str: Data direction, as a string
 * @request_buffer: The data buffer address
 * @request_bufflen: The data buffer buffer length
 * @timeout: Request timeout in seconds
 * @retries: Number of times to retry request
 */
probe scsi.ioexecute
	= module("scsi_mod").function("scsi_execute")!,
	  kernel.function("scsi_execute")?
{
	host_no = $sdev->host->host_no
	channel = $sdev->channel
	lun = $sdev->lun
	dev_id = $sdev->id
	device_state = $sdev->sdev_state
	device_state_str = describe_device_state(device_state)
	data_direction = $data_direction
	data_direction_str = describe_data_direction(data_direction)
	request_buffer = $buffer
	request_bufflen = $bufflen
	timeout = $timeout
	retries = $retries
}

/**
 * probe scsi.set_state - Order SCSI device state change
 * @host_no: The host number
 * @channel: The channel number
 * @lun: The lun number
 * @dev_id: The scsi device id
 * @old_state: The current state of the device
 * @old_state_str: The current state of the device, as a string
 * @state: The new state of the device
 * @state_str: The new state of the device, as a string
 */
probe scsi.set_state
	= module("scsi_mod").function("scsi_device_set_state")!,
	  kernel.function("scsi_device_set_state")?
{
	state = $state
	state_str = describe_device_state(state)

	host_no = $sdev->host->host_no
	channel = $sdev->channel
	lun = $sdev->lun
	dev_id = $sdev->id
	old_state = $sdev->sdev_state
	old_state_str = describe_device_state(old_state)
}