1 // SPDX-License-Identifier: GPL-2.0-only
7  *  generic mid-level SCSI driver
16  *      Thomas Wuensche <tw@fgb1.fgb.mw.tu-muenchen.de>
19  *  add scatter-gather, multiple outstanding request, and other
23  *  support added by Michael Neuffer <mike@i-connect.net>
36  *  Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli
80  * Note - the initial logging level can be set here to log events at boot time.
134 		if (((level > 0) && (cmd->result || disposition != SUCCESS)) ||  in scsi_log_completion()
138 			if (scsi_status_is_check_condition(cmd->result))  in scsi_log_completion()
143 					    scsi_host_busy(cmd->device->host),  in scsi_log_completion()
144 					    cmd->device->host->host_failed);  in scsi_log_completion()
151  * scsi_finish_command - cleanup and pass command back to upper layer
154  * Description: Pass command off to upper layer for finishing of I/O
160 	struct scsi_device *sdev = cmd->device;  in scsi_finish_command()
162 	struct Scsi_Host *shost = sdev->host;  in scsi_finish_command()
172 	if (atomic_read(&shost->host_blocked))  in scsi_finish_command()
173 		atomic_set(&shost->host_blocked, 0);  in scsi_finish_command()
174 	if (atomic_read(&starget->target_blocked))  in scsi_finish_command()
175 		atomic_set(&starget->target_blocked, 0);  in scsi_finish_command()
176 	if (atomic_read(&sdev->device_blocked))  in scsi_finish_command()
177 		atomic_set(&sdev->device_blocked, 0);  in scsi_finish_command()
181 				"(result %x)\n", cmd->result));  in scsi_finish_command()
187 		if (drv->done)  in scsi_finish_command()
188 			good_bytes = drv->done(cmd);  in scsi_finish_command()
192 		 * residue if drv->done() error processing indicates no  in scsi_finish_command()
196 			good_bytes -= scsi_get_resid(cmd);  in scsi_finish_command()
207 	return min_t(int, sdev->host->can_queue, 4096);  in scsi_device_max_queue_depth()
211  * scsi_change_queue_depth - change a device's queue depth
213  * @depth: number of commands allowed to be queued to the driver
215  * Sets the device queue depth and returns the new value.
217 int scsi_change_queue_depth(struct scsi_device *sdev, int depth)  in scsi_change_queue_depth()  argument
219 	depth = min_t(int, depth, scsi_device_max_queue_depth(sdev));  in scsi_change_queue_depth()
221 	if (depth > 0) {  in scsi_change_queue_depth()
222 		sdev->queue_depth = depth;  in scsi_change_queue_depth()
226 	if (sdev->request_queue)  in scsi_change_queue_depth()
227 		blk_set_queue_depth(sdev->request_queue, depth);  in scsi_change_queue_depth()
229 	sbitmap_resize(&sdev->budget_map, sdev->queue_depth);  in scsi_change_queue_depth()
231 	return sdev->queue_depth;  in scsi_change_queue_depth()
236  * scsi_track_queue_full - track QUEUE_FULL events to adjust queue depth
238  * @depth: Current number of outstanding SCSI commands on this device,
243  * 		need to adjust the queue depth on the device.
245  * Returns:	0 - No change needed, >0 - Adjust queue depth to this new depth,
246  * 		-1 - Drop back to untagged operation using host->cmd_per_lun
247  * 			as the untagged command depth
254 int scsi_track_queue_full(struct scsi_device *sdev, int depth)  in scsi_track_queue_full()  argument
262 	if ((jiffies >> 4) == (sdev->last_queue_full_time >> 4))  in scsi_track_queue_full()
265 	sdev->last_queue_full_time = jiffies;  in scsi_track_queue_full()
266 	if (sdev->last_queue_full_depth != depth) {  in scsi_track_queue_full()
267 		sdev->last_queue_full_count = 1;  in scsi_track_queue_full()
268 		sdev->last_queue_full_depth = depth;  in scsi_track_queue_full()
270 		sdev->last_queue_full_count++;  in scsi_track_queue_full()
273 	if (sdev->last_queue_full_count <= 10)  in scsi_track_queue_full()
276 	return scsi_change_queue_depth(sdev, depth);  in scsi_track_queue_full()
281  * scsi_vpd_inquiry - Request a device provide us with a VPD page
299 		return -EINVAL;  in scsi_vpd_inquiry()
315 		return -EIO;  in scsi_vpd_inquiry()
322 		return -EIO;  in scsi_vpd_inquiry()
326 		return -EIO;  in scsi_vpd_inquiry()
341 	if (sdev->no_vpd_size)  in scsi_get_vpd_size()
354 			dev_warn_once(&sdev->sdev_gendev,  in scsi_get_vpd_size()
360 		result -= SCSI_VPD_HEADER_SIZE;  in scsi_get_vpd_size()
375 		dev_warn_once(&sdev->sdev_gendev,  in scsi_get_vpd_size()
385  * scsi_get_vpd_page - Get Vital Product Data from a SCSI device
395  * supported or its content cannot be retrieved, -EINVAL is returned.
403 		return -EINVAL;  in scsi_get_vpd_page()
407 		return -EINVAL;  in scsi_get_vpd_page()
418 		return -EINVAL;  in scsi_get_vpd_page()
420 		dev_warn_once(&sdev->sdev_gendev,  in scsi_get_vpd_page()
429  * scsi_get_vpd_buf - Get Vital Product Data from a SCSI device
453 	result = scsi_vpd_inquiry(sdev, vpd_buf->data, page, vpd_len);  in scsi_get_vpd_buf()
459 		dev_warn_once(&sdev->sdev_gendev,  in scsi_get_vpd_buf()
467 	vpd_buf->len = result;  in scsi_get_vpd_buf()
481 	mutex_lock(&sdev->inquiry_mutex);  in scsi_update_vpd_page()
483 				      lockdep_is_held(&sdev->inquiry_mutex));  in scsi_update_vpd_page()
484 	mutex_unlock(&sdev->inquiry_mutex);  in scsi_update_vpd_page()
491  * scsi_attach_vpd - Attach Vital Product Data to a SCSI device structure
512 	for (i = 4; i < vpd_buf->len; i++) {  in scsi_attach_vpd()
513 		switch (vpd_buf->data[i]) {  in scsi_attach_vpd()
515 			scsi_update_vpd_page(sdev, 0x0, &sdev->vpd_pg0);  in scsi_attach_vpd()
518 			scsi_update_vpd_page(sdev, 0x80, &sdev->vpd_pg80);  in scsi_attach_vpd()
521 			scsi_update_vpd_page(sdev, 0x83, &sdev->vpd_pg83);  in scsi_attach_vpd()
524 			scsi_update_vpd_page(sdev, 0x89, &sdev->vpd_pg89);  in scsi_attach_vpd()
527 			scsi_update_vpd_page(sdev, 0xb0, &sdev->vpd_pgb0);  in scsi_attach_vpd()
530 			scsi_update_vpd_page(sdev, 0xb1, &sdev->vpd_pgb1);  in scsi_attach_vpd()
533 			scsi_update_vpd_page(sdev, 0xb2, &sdev->vpd_pgb2);  in scsi_attach_vpd()
536 			scsi_update_vpd_page(sdev, 0xb7, &sdev->vpd_pgb7);  in scsi_attach_vpd()
546  * scsi_report_opcode - Find out if a given command is supported
555  * have a service action, @sa must be 0. Returns -EINVAL if RSOC fails,
570 	if (sdev->no_report_opcodes || sdev->scsi_level < SCSI_SPC_3)  in scsi_report_opcode()
571 		return -EINVAL;  in scsi_report_opcode()
576 		dev_warn_once(&sdev->sdev_gendev,  in scsi_report_opcode()
579 		return -EINVAL;  in scsi_report_opcode()
603 		return -EINVAL;  in scsi_report_opcode()
629 	 * See SPC-6, One_command parameter data format for  in scsi_cdl_check_cmd()
632 	 *  - rwcdlp == 0: then cdlp indicates support for the A mode page when  in scsi_cdl_check_cmd()
635 	 *  - rwcdlp == 1: then cdlp indicates support for the T2A mode page  in scsi_cdl_check_cmd()
647  * scsi_cdl_check - Check if a SCSI device supports Command Duration Limits
656 	 * Support for CDL was defined in SPC-5. Ignore devices reporting an  in scsi_cdl_check()
661 	if (sdev->scsi_level < SCSI_SPC_5) {  in scsi_cdl_check()
662 		sdev->cdl_supported = 0;  in scsi_cdl_check()
668 		sdev->cdl_supported = 0;  in scsi_cdl_check()
684 		sdev->use_16_for_rw = 1;  in scsi_cdl_check()
685 		sdev->use_10_for_rw = 0;  in scsi_cdl_check()
687 		sdev->cdl_supported = 1;  in scsi_cdl_check()
694 		scsi_cdl_enable(sdev, sdev->cdl_enable);  in scsi_cdl_check()
696 		sdev->cdl_supported = 0;  in scsi_cdl_check()
703  * scsi_cdl_enable - Enable or disable a SCSI device supports for Command
714 	if (!sdev->cdl_supported)  in scsi_cdl_enable()
715 		return -EOPNOTSUPP;  in scsi_cdl_enable()
718 	is_ata = rcu_dereference(sdev->vpd_pg89);  in scsi_cdl_enable()
733 			return -EINVAL;  in scsi_cdl_enable()
737 			    data.length - data.header_length -  in scsi_cdl_enable()
765 					dev_name(&sdev->sdev_gendev), &sshdr);  in scsi_cdl_enable()
771 	sdev->cdl_enable = enable;  in scsi_cdl_enable()
777  * scsi_device_get  -  get an additional reference to a scsi_device
789 	if (sdev->sdev_state == SDEV_DEL || sdev->sdev_state == SDEV_CANCEL)  in scsi_device_get()
791 	if (!try_module_get(sdev->host->hostt->module))  in scsi_device_get()
793 	if (!get_device(&sdev->sdev_gendev))  in scsi_device_get()
798 	module_put(sdev->host->hostt->module);  in scsi_device_get()
800 	return -ENXIO;  in scsi_device_get()
805  * scsi_device_put  -  release a reference to a scsi_device
814 	struct module *mod = sdev->host->hostt->module;  in scsi_device_put()
816 	put_device(&sdev->sdev_gendev);  in scsi_device_put()
825 	struct list_head *list = (prev ? &prev->siblings : &shost->__devices);  in __scsi_iterate_devices()
829 	spin_lock_irqsave(shost->host_lock, flags);  in __scsi_iterate_devices()
830 	while (list->next != &shost->__devices) {  in __scsi_iterate_devices()
831 		next = list_entry(list->next, struct scsi_device, siblings);  in __scsi_iterate_devices()
836 		list = list->next;  in __scsi_iterate_devices()
838 	spin_unlock_irqrestore(shost->host_lock, flags);  in __scsi_iterate_devices()
847  * starget_for_each_device  -  helper to walk all devices of a target
859 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);  in starget_for_each_device()
863 		if ((sdev->channel == starget->channel) &&  in starget_for_each_device()
864 		    (sdev->id == starget->id))  in starget_for_each_device()
871  * __starget_for_each_device - helper to walk all devices of a target (UNLOCKED)
878  * protected by shost->host_lock.
887 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);  in __starget_for_each_device()
891 		if ((sdev->channel == starget->channel) &&  in __starget_for_each_device()
892 		    (sdev->id == starget->id))  in __starget_for_each_device()
899  * __scsi_device_lookup_by_target - find a device given the target (UNLOCKED)
918 	list_for_each_entry(sdev, &starget->devices, same_target_siblings) {  in __scsi_device_lookup_by_target()
919 		if (sdev->sdev_state == SDEV_DEL)  in __scsi_device_lookup_by_target()
921 		if (sdev->lun ==lun)  in __scsi_device_lookup_by_target()
930  * scsi_device_lookup_by_target - find a device given the target
942 	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);  in scsi_device_lookup_by_target()
945 	spin_lock_irqsave(shost->host_lock, flags);  in scsi_device_lookup_by_target()
949 	spin_unlock_irqrestore(shost->host_lock, flags);  in scsi_device_lookup_by_target()
956  * __scsi_device_lookup - find a device given the host (UNLOCKED)
976 	list_for_each_entry(sdev, &shost->__devices, siblings) {  in __scsi_device_lookup()
977 		if (sdev->sdev_state == SDEV_DEL)  in __scsi_device_lookup()
979 		if (sdev->channel == channel && sdev->id == id &&  in __scsi_device_lookup()
980 				sdev->lun ==lun)  in __scsi_device_lookup()
989  * scsi_device_lookup - find a device given the host
1005 	spin_lock_irqsave(shost->host_lock, flags);  in scsi_device_lookup()
1009 	spin_unlock_irqrestore(shost->host_lock, flags);  in scsi_device_lookup()
1057 	       -error);  in init_scsi()