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v3.1
  1/*
  2 * USB Attached SCSI
  3 * Note that this is not the same as the USB Mass Storage driver
  4 *
  5 * Copyright Matthew Wilcox for Intel Corp, 2010
  6 * Copyright Sarah Sharp for Intel Corp, 2010
  7 *
  8 * Distributed under the terms of the GNU GPL, version two.
  9 */
 10
 11#include <linux/blkdev.h>
 12#include <linux/slab.h>
 13#include <linux/types.h>
 
 14#include <linux/usb.h>
 
 15#include <linux/usb/storage.h>
 
 16
 17#include <scsi/scsi.h>
 18#include <scsi/scsi_dbg.h>
 19#include <scsi/scsi_cmnd.h>
 20#include <scsi/scsi_device.h>
 21#include <scsi/scsi_host.h>
 22#include <scsi/scsi_tcq.h>
 23
 24/* Common header for all IUs */
 25struct iu {
 26	__u8 iu_id;
 27	__u8 rsvd1;
 28	__be16 tag;
 29};
 30
 31enum {
 32	IU_ID_COMMAND		= 0x01,
 33	IU_ID_STATUS		= 0x03,
 34	IU_ID_RESPONSE		= 0x04,
 35	IU_ID_TASK_MGMT		= 0x05,
 36	IU_ID_READ_READY	= 0x06,
 37	IU_ID_WRITE_READY	= 0x07,
 38};
 39
 40struct command_iu {
 41	__u8 iu_id;
 42	__u8 rsvd1;
 43	__be16 tag;
 44	__u8 prio_attr;
 45	__u8 rsvd5;
 46	__u8 len;
 47	__u8 rsvd7;
 48	struct scsi_lun lun;
 49	__u8 cdb[16];	/* XXX: Overflow-checking tools may misunderstand */
 50};
 51
 52/*
 53 * Also used for the Read Ready and Write Ready IUs since they have the
 54 * same first four bytes
 55 */
 56struct sense_iu {
 57	__u8 iu_id;
 58	__u8 rsvd1;
 59	__be16 tag;
 60	__be16 status_qual;
 61	__u8 status;
 62	__u8 rsvd7[7];
 63	__be16 len;
 64	__u8 sense[SCSI_SENSE_BUFFERSIZE];
 65};
 66
 67/*
 68 * The r00-r01c specs define this version of the SENSE IU data structure.
 69 * It's still in use by several different firmware releases.
 70 */
 71struct sense_iu_old {
 72	__u8 iu_id;
 73	__u8 rsvd1;
 74	__be16 tag;
 75	__be16 len;
 76	__u8 status;
 77	__u8 service_response;
 78	__u8 sense[SCSI_SENSE_BUFFERSIZE];
 79};
 80
 81enum {
 82	CMD_PIPE_ID		= 1,
 83	STATUS_PIPE_ID		= 2,
 84	DATA_IN_PIPE_ID		= 3,
 85	DATA_OUT_PIPE_ID	= 4,
 86
 87	UAS_SIMPLE_TAG		= 0,
 88	UAS_HEAD_TAG		= 1,
 89	UAS_ORDERED_TAG		= 2,
 90	UAS_ACA			= 4,
 91};
 92
 93struct uas_dev_info {
 94	struct usb_interface *intf;
 95	struct usb_device *udev;
 96	int qdepth;
 97	unsigned cmd_pipe, status_pipe, data_in_pipe, data_out_pipe;
 98	unsigned use_streams:1;
 99	unsigned uas_sense_old:1;
 
 
100};
101
102enum {
103	ALLOC_STATUS_URB	= (1 << 0),
104	SUBMIT_STATUS_URB	= (1 << 1),
105	ALLOC_DATA_IN_URB	= (1 << 2),
106	SUBMIT_DATA_IN_URB	= (1 << 3),
107	ALLOC_DATA_OUT_URB	= (1 << 4),
108	SUBMIT_DATA_OUT_URB	= (1 << 5),
109	ALLOC_CMD_URB		= (1 << 6),
110	SUBMIT_CMD_URB		= (1 << 7),
111};
112
113/* Overrides scsi_pointer */
114struct uas_cmd_info {
115	unsigned int state;
116	unsigned int stream;
117	struct urb *cmd_urb;
 
118	struct urb *status_urb;
119	struct urb *data_in_urb;
120	struct urb *data_out_urb;
121	struct list_head list;
122};
123
124/* I hate forward declarations, but I actually have a loop */
125static int uas_submit_urbs(struct scsi_cmnd *cmnd,
126				struct uas_dev_info *devinfo, gfp_t gfp);
 
127
 
128static DEFINE_SPINLOCK(uas_work_lock);
129static LIST_HEAD(uas_work_list);
130
131static void uas_do_work(struct work_struct *work)
132{
133	struct uas_cmd_info *cmdinfo;
 
134	struct list_head list;
 
135
136	spin_lock_irq(&uas_work_lock);
137	list_replace_init(&uas_work_list, &list);
138	spin_unlock_irq(&uas_work_lock);
139
140	list_for_each_entry(cmdinfo, &list, list) {
141		struct scsi_pointer *scp = (void *)cmdinfo;
142		struct scsi_cmnd *cmnd = container_of(scp,
143							struct scsi_cmnd, SCp);
144		uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_NOIO);
 
 
 
 
 
 
 
145	}
146}
147
148static DECLARE_WORK(uas_work, uas_do_work);
149
150static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
151{
152	struct sense_iu *sense_iu = urb->transfer_buffer;
153	struct scsi_device *sdev = cmnd->device;
154
155	if (urb->actual_length > 16) {
156		unsigned len = be16_to_cpup(&sense_iu->len);
157		if (len + 16 != urb->actual_length) {
158			int newlen = min(len + 16, urb->actual_length) - 16;
159			if (newlen < 0)
160				newlen = 0;
161			sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
162				"disagrees with IU sense data length %d, "
163				"using %d bytes of sense data\n", __func__,
164					urb->actual_length, len, newlen);
165			len = newlen;
166		}
167		memcpy(cmnd->sense_buffer, sense_iu->sense, len);
168	}
169
170	cmnd->result = sense_iu->status;
171	if (sdev->current_cmnd)
172		sdev->current_cmnd = NULL;
173	cmnd->scsi_done(cmnd);
174	usb_free_urb(urb);
175}
176
177static void uas_sense_old(struct urb *urb, struct scsi_cmnd *cmnd)
178{
179	struct sense_iu_old *sense_iu = urb->transfer_buffer;
180	struct scsi_device *sdev = cmnd->device;
181
182	if (urb->actual_length > 8) {
183		unsigned len = be16_to_cpup(&sense_iu->len) - 2;
184		if (len + 8 != urb->actual_length) {
185			int newlen = min(len + 8, urb->actual_length) - 8;
186			if (newlen < 0)
187				newlen = 0;
188			sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
189				"disagrees with IU sense data length %d, "
190				"using %d bytes of sense data\n", __func__,
191					urb->actual_length, len, newlen);
192			len = newlen;
193		}
194		memcpy(cmnd->sense_buffer, sense_iu->sense, len);
195	}
196
197	cmnd->result = sense_iu->status;
198	if (sdev->current_cmnd)
199		sdev->current_cmnd = NULL;
200	cmnd->scsi_done(cmnd);
201	usb_free_urb(urb);
202}
203
204static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
205							unsigned direction)
206{
207	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
208	int err;
209
210	cmdinfo->state = direction | SUBMIT_STATUS_URB;
211	err = uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_ATOMIC);
212	if (err) {
213		spin_lock(&uas_work_lock);
214		list_add_tail(&cmdinfo->list, &uas_work_list);
215		spin_unlock(&uas_work_lock);
216		schedule_work(&uas_work);
217	}
218}
219
220static void uas_stat_cmplt(struct urb *urb)
221{
222	struct iu *iu = urb->transfer_buffer;
223	struct scsi_device *sdev = urb->context;
224	struct uas_dev_info *devinfo = sdev->hostdata;
225	struct scsi_cmnd *cmnd;
226	u16 tag;
 
227
228	if (urb->status) {
229		dev_err(&urb->dev->dev, "URB BAD STATUS %d\n", urb->status);
230		usb_free_urb(urb);
 
231		return;
232	}
233
234	tag = be16_to_cpup(&iu->tag) - 1;
235	if (sdev->current_cmnd)
236		cmnd = sdev->current_cmnd;
237	else
238		cmnd = scsi_find_tag(sdev, tag);
239	if (!cmnd)
 
 
 
 
 
 
 
240		return;
 
241
242	switch (iu->iu_id) {
243	case IU_ID_STATUS:
 
 
 
244		if (urb->actual_length < 16)
245			devinfo->uas_sense_old = 1;
246		if (devinfo->uas_sense_old)
247			uas_sense_old(urb, cmnd);
248		else
249			uas_sense(urb, cmnd);
250		break;
251	case IU_ID_READ_READY:
252		uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
253		break;
254	case IU_ID_WRITE_READY:
255		uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
256		break;
257	default:
258		scmd_printk(KERN_ERR, cmnd,
259			"Bogus IU (%d) received on status pipe\n", iu->iu_id);
260	}
 
 
 
 
 
 
 
 
 
261}
262
263static void uas_data_cmplt(struct urb *urb)
264{
265	struct scsi_data_buffer *sdb = urb->context;
266	sdb->resid = sdb->length - urb->actual_length;
267	usb_free_urb(urb);
268}
269
270static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
271				unsigned int pipe, u16 stream_id,
272				struct scsi_data_buffer *sdb,
273				enum dma_data_direction dir)
274{
275	struct usb_device *udev = devinfo->udev;
276	struct urb *urb = usb_alloc_urb(0, gfp);
277
278	if (!urb)
279		goto out;
280	usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length, uas_data_cmplt,
281									sdb);
282	if (devinfo->use_streams)
283		urb->stream_id = stream_id;
284	urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
285	urb->sg = sdb->table.sgl;
286 out:
287	return urb;
288}
289
290static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
291					struct scsi_cmnd *cmnd, u16 stream_id)
292{
293	struct usb_device *udev = devinfo->udev;
294	struct urb *urb = usb_alloc_urb(0, gfp);
295	struct sense_iu *iu;
296
297	if (!urb)
298		goto out;
299
300	iu = kzalloc(sizeof(*iu), gfp);
301	if (!iu)
302		goto free;
303
304	usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
305						uas_stat_cmplt, cmnd->device);
306	urb->stream_id = stream_id;
307	urb->transfer_flags |= URB_FREE_BUFFER;
308 out:
309	return urb;
310 free:
311	usb_free_urb(urb);
312	return NULL;
313}
314
315static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
316					struct scsi_cmnd *cmnd, u16 stream_id)
317{
318	struct usb_device *udev = devinfo->udev;
319	struct scsi_device *sdev = cmnd->device;
320	struct urb *urb = usb_alloc_urb(0, gfp);
321	struct command_iu *iu;
322	int len;
323
324	if (!urb)
325		goto out;
326
327	len = cmnd->cmd_len - 16;
328	if (len < 0)
329		len = 0;
330	len = ALIGN(len, 4);
331	iu = kzalloc(sizeof(*iu) + len, gfp);
332	if (!iu)
333		goto free;
334
335	iu->iu_id = IU_ID_COMMAND;
336	iu->tag = cpu_to_be16(stream_id);
 
 
 
337	iu->prio_attr = UAS_SIMPLE_TAG;
338	iu->len = len;
339	int_to_scsilun(sdev->lun, &iu->lun);
340	memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);
341
342	usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
343							usb_free_urb, NULL);
344	urb->transfer_flags |= URB_FREE_BUFFER;
345 out:
346	return urb;
347 free:
348	usb_free_urb(urb);
349	return NULL;
350}
351
352/*
353 * Why should I request the Status IU before sending the Command IU?  Spec
354 * says to, but also says the device may receive them in any order.  Seems
355 * daft to me.
356 */
357
358static int uas_submit_urbs(struct scsi_cmnd *cmnd,
359					struct uas_dev_info *devinfo, gfp_t gfp)
360{
361	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
362
363	if (cmdinfo->state & ALLOC_STATUS_URB) {
364		cmdinfo->status_urb = uas_alloc_sense_urb(devinfo, gfp, cmnd,
365							  cmdinfo->stream);
366		if (!cmdinfo->status_urb)
367			return SCSI_MLQUEUE_DEVICE_BUSY;
368		cmdinfo->state &= ~ALLOC_STATUS_URB;
369	}
370
371	if (cmdinfo->state & SUBMIT_STATUS_URB) {
372		if (usb_submit_urb(cmdinfo->status_urb, gfp)) {
373			scmd_printk(KERN_INFO, cmnd,
374					"sense urb submission failure\n");
375			return SCSI_MLQUEUE_DEVICE_BUSY;
376		}
377		cmdinfo->state &= ~SUBMIT_STATUS_URB;
378	}
379
380	if (cmdinfo->state & ALLOC_DATA_IN_URB) {
381		cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, gfp,
382					devinfo->data_in_pipe, cmdinfo->stream,
383					scsi_in(cmnd), DMA_FROM_DEVICE);
384		if (!cmdinfo->data_in_urb)
385			return SCSI_MLQUEUE_DEVICE_BUSY;
386		cmdinfo->state &= ~ALLOC_DATA_IN_URB;
387	}
388
389	if (cmdinfo->state & SUBMIT_DATA_IN_URB) {
390		if (usb_submit_urb(cmdinfo->data_in_urb, gfp)) {
391			scmd_printk(KERN_INFO, cmnd,
392					"data in urb submission failure\n");
393			return SCSI_MLQUEUE_DEVICE_BUSY;
394		}
395		cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
396	}
397
398	if (cmdinfo->state & ALLOC_DATA_OUT_URB) {
399		cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, gfp,
400					devinfo->data_out_pipe, cmdinfo->stream,
401					scsi_out(cmnd), DMA_TO_DEVICE);
402		if (!cmdinfo->data_out_urb)
403			return SCSI_MLQUEUE_DEVICE_BUSY;
404		cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
405	}
406
407	if (cmdinfo->state & SUBMIT_DATA_OUT_URB) {
408		if (usb_submit_urb(cmdinfo->data_out_urb, gfp)) {
409			scmd_printk(KERN_INFO, cmnd,
410					"data out urb submission failure\n");
411			return SCSI_MLQUEUE_DEVICE_BUSY;
412		}
413		cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
414	}
415
416	if (cmdinfo->state & ALLOC_CMD_URB) {
417		cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, gfp, cmnd,
418							cmdinfo->stream);
419		if (!cmdinfo->cmd_urb)
420			return SCSI_MLQUEUE_DEVICE_BUSY;
421		cmdinfo->state &= ~ALLOC_CMD_URB;
422	}
423
424	if (cmdinfo->state & SUBMIT_CMD_URB) {
425		if (usb_submit_urb(cmdinfo->cmd_urb, gfp)) {
426			scmd_printk(KERN_INFO, cmnd,
427					"cmd urb submission failure\n");
428			return SCSI_MLQUEUE_DEVICE_BUSY;
429		}
430		cmdinfo->state &= ~SUBMIT_CMD_URB;
431	}
432
433	return 0;
434}
435
436static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
437					void (*done)(struct scsi_cmnd *))
438{
439	struct scsi_device *sdev = cmnd->device;
440	struct uas_dev_info *devinfo = sdev->hostdata;
441	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
442	int err;
443
444	BUILD_BUG_ON(sizeof(struct uas_cmd_info) > sizeof(struct scsi_pointer));
445
446	if (!cmdinfo->status_urb && sdev->current_cmnd)
447		return SCSI_MLQUEUE_DEVICE_BUSY;
448
449	if (blk_rq_tagged(cmnd->request)) {
450		cmdinfo->stream = cmnd->request->tag + 1;
451	} else {
452		sdev->current_cmnd = cmnd;
453		cmdinfo->stream = 1;
454	}
455
456	cmnd->scsi_done = done;
457
458	cmdinfo->state = ALLOC_STATUS_URB | SUBMIT_STATUS_URB |
459			ALLOC_CMD_URB | SUBMIT_CMD_URB;
460
461	switch (cmnd->sc_data_direction) {
462	case DMA_FROM_DEVICE:
463		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
464		break;
465	case DMA_BIDIRECTIONAL:
466		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
467	case DMA_TO_DEVICE:
468		cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
469	case DMA_NONE:
470		break;
471	}
472
473	if (!devinfo->use_streams) {
474		cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
 
475		cmdinfo->stream = 0;
476	}
477
478	err = uas_submit_urbs(cmnd, devinfo, GFP_ATOMIC);
479	if (err) {
480		/* If we did nothing, give up now */
481		if (cmdinfo->state & SUBMIT_STATUS_URB) {
482			usb_free_urb(cmdinfo->status_urb);
483			return SCSI_MLQUEUE_DEVICE_BUSY;
484		}
485		spin_lock(&uas_work_lock);
486		list_add_tail(&cmdinfo->list, &uas_work_list);
487		spin_unlock(&uas_work_lock);
488		schedule_work(&uas_work);
489	}
490
491	return 0;
492}
493
494static DEF_SCSI_QCMD(uas_queuecommand)
495
496static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
497{
498	struct scsi_device *sdev = cmnd->device;
499	sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
500							cmnd->request->tag);
501
502/* XXX: Send ABORT TASK Task Management command */
503	return FAILED;
504}
505
506static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
507{
508	struct scsi_device *sdev = cmnd->device;
509	sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
510							cmnd->request->tag);
511
512/* XXX: Send LOGICAL UNIT RESET Task Management command */
513	return FAILED;
514}
515
516static int uas_eh_target_reset_handler(struct scsi_cmnd *cmnd)
517{
518	struct scsi_device *sdev = cmnd->device;
519	sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
520							cmnd->request->tag);
521
522/* XXX: Can we reset just the one USB interface?
523 * Would calling usb_set_interface() have the right effect?
524 */
525	return FAILED;
526}
527
528static int uas_eh_bus_reset_handler(struct scsi_cmnd *cmnd)
529{
530	struct scsi_device *sdev = cmnd->device;
531	struct uas_dev_info *devinfo = sdev->hostdata;
532	struct usb_device *udev = devinfo->udev;
533
534	sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
535							cmnd->request->tag);
536
537	if (usb_reset_device(udev))
538		return SUCCESS;
539
540	return FAILED;
541}
542
543static int uas_slave_alloc(struct scsi_device *sdev)
544{
545	sdev->hostdata = (void *)sdev->host->hostdata[0];
546	return 0;
547}
548
549static int uas_slave_configure(struct scsi_device *sdev)
550{
551	struct uas_dev_info *devinfo = sdev->hostdata;
552	scsi_set_tag_type(sdev, MSG_ORDERED_TAG);
553	scsi_activate_tcq(sdev, devinfo->qdepth - 1);
554	return 0;
555}
556
557static struct scsi_host_template uas_host_template = {
558	.module = THIS_MODULE,
559	.name = "uas",
560	.queuecommand = uas_queuecommand,
561	.slave_alloc = uas_slave_alloc,
562	.slave_configure = uas_slave_configure,
563	.eh_abort_handler = uas_eh_abort_handler,
564	.eh_device_reset_handler = uas_eh_device_reset_handler,
565	.eh_target_reset_handler = uas_eh_target_reset_handler,
566	.eh_bus_reset_handler = uas_eh_bus_reset_handler,
567	.can_queue = 65536,	/* Is there a limit on the _host_ ? */
568	.this_id = -1,
569	.sg_tablesize = SG_NONE,
570	.cmd_per_lun = 1,	/* until we override it */
571	.skip_settle_delay = 1,
572	.ordered_tag = 1,
573};
574
575static struct usb_device_id uas_usb_ids[] = {
576	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
577	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
578	/* 0xaa is a prototype device I happen to have access to */
579	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, 0xaa) },
580	{ }
581};
582MODULE_DEVICE_TABLE(usb, uas_usb_ids);
583
584static int uas_is_interface(struct usb_host_interface *intf)
585{
586	return (intf->desc.bInterfaceClass == USB_CLASS_MASS_STORAGE &&
587		intf->desc.bInterfaceSubClass == USB_SC_SCSI &&
588		intf->desc.bInterfaceProtocol == USB_PR_UAS);
589}
590
 
 
 
 
 
 
 
 
 
 
 
 
591static int uas_switch_interface(struct usb_device *udev,
592						struct usb_interface *intf)
593{
594	int i;
595
596	if (uas_is_interface(intf->cur_altsetting))
597		return 0;
598
599	for (i = 0; i < intf->num_altsetting; i++) {
600		struct usb_host_interface *alt = &intf->altsetting[i];
601		if (alt == intf->cur_altsetting)
602			continue;
603		if (uas_is_interface(alt))
 
604			return usb_set_interface(udev,
605						alt->desc.bInterfaceNumber,
606						alt->desc.bAlternateSetting);
 
607	}
608
609	return -ENODEV;
610}
611
612static void uas_configure_endpoints(struct uas_dev_info *devinfo)
613{
614	struct usb_host_endpoint *eps[4] = { };
615	struct usb_interface *intf = devinfo->intf;
616	struct usb_device *udev = devinfo->udev;
617	struct usb_host_endpoint *endpoint = intf->cur_altsetting->endpoint;
618	unsigned i, n_endpoints = intf->cur_altsetting->desc.bNumEndpoints;
619
620	devinfo->uas_sense_old = 0;
 
621
622	for (i = 0; i < n_endpoints; i++) {
623		unsigned char *extra = endpoint[i].extra;
624		int len = endpoint[i].extralen;
625		while (len > 1) {
626			if (extra[1] == USB_DT_PIPE_USAGE) {
627				unsigned pipe_id = extra[2];
628				if (pipe_id > 0 && pipe_id < 5)
629					eps[pipe_id - 1] = &endpoint[i];
630				break;
631			}
632			len -= extra[0];
633			extra += extra[0];
634		}
635	}
636
637	/*
638	 * Assume that if we didn't find a control pipe descriptor, we're
639	 * using a device with old firmware that happens to be set up like
640	 * this.
641	 */
642	if (!eps[0]) {
643		devinfo->cmd_pipe = usb_sndbulkpipe(udev, 1);
644		devinfo->status_pipe = usb_rcvbulkpipe(udev, 1);
645		devinfo->data_in_pipe = usb_rcvbulkpipe(udev, 2);
646		devinfo->data_out_pipe = usb_sndbulkpipe(udev, 2);
647
648		eps[1] = usb_pipe_endpoint(udev, devinfo->status_pipe);
649		eps[2] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
650		eps[3] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
651	} else {
652		devinfo->cmd_pipe = usb_sndbulkpipe(udev,
653						eps[0]->desc.bEndpointAddress);
654		devinfo->status_pipe = usb_rcvbulkpipe(udev,
655						eps[1]->desc.bEndpointAddress);
656		devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
657						eps[2]->desc.bEndpointAddress);
658		devinfo->data_out_pipe = usb_sndbulkpipe(udev,
659						eps[3]->desc.bEndpointAddress);
660	}
661
662	devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1, 3, 256,
663								GFP_KERNEL);
664	if (devinfo->qdepth < 0) {
665		devinfo->qdepth = 256;
666		devinfo->use_streams = 0;
667	} else {
668		devinfo->use_streams = 1;
669	}
670}
671
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
672/*
673 * XXX: What I'd like to do here is register a SCSI host for each USB host in
674 * the system.  Follow usb-storage's design of registering a SCSI host for
675 * each USB device for the moment.  Can implement this by walking up the
676 * USB hierarchy until we find a USB host.
677 */
678static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
679{
680	int result;
681	struct Scsi_Host *shost;
682	struct uas_dev_info *devinfo;
683	struct usb_device *udev = interface_to_usbdev(intf);
684
685	if (uas_switch_interface(udev, intf))
686		return -ENODEV;
687
688	devinfo = kmalloc(sizeof(struct uas_dev_info), GFP_KERNEL);
689	if (!devinfo)
690		return -ENOMEM;
691
692	result = -ENOMEM;
693	shost = scsi_host_alloc(&uas_host_template, sizeof(void *));
694	if (!shost)
695		goto free;
696
697	shost->max_cmd_len = 16 + 252;
698	shost->max_id = 1;
699	shost->sg_tablesize = udev->bus->sg_tablesize;
700
701	result = scsi_add_host(shost, &intf->dev);
 
 
 
 
702	if (result)
703		goto free;
 
 
 
 
 
704	shost->hostdata[0] = (unsigned long)devinfo;
705
706	devinfo->intf = intf;
707	devinfo->udev = udev;
708	uas_configure_endpoints(devinfo);
709
710	scsi_scan_host(shost);
711	usb_set_intfdata(intf, shost);
712	return result;
 
 
 
 
 
 
713 free:
714	kfree(devinfo);
715	if (shost)
716		scsi_host_put(shost);
717	return result;
718}
719
720static int uas_pre_reset(struct usb_interface *intf)
721{
722/* XXX: Need to return 1 if it's not our device in error handling */
723	return 0;
724}
725
726static int uas_post_reset(struct usb_interface *intf)
727{
728/* XXX: Need to return 1 if it's not our device in error handling */
729	return 0;
730}
731
732static void uas_disconnect(struct usb_interface *intf)
733{
734	struct usb_device *udev = interface_to_usbdev(intf);
735	struct usb_host_endpoint *eps[3];
736	struct Scsi_Host *shost = usb_get_intfdata(intf);
737	struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
738
739	scsi_remove_host(shost);
740
741	eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
742	eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
743	eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
744	usb_free_streams(intf, eps, 3, GFP_KERNEL);
745
746	kfree(devinfo);
747}
748
749/*
750 * XXX: Should this plug into libusual so we can auto-upgrade devices from
751 * Bulk-Only to UAS?
752 */
753static struct usb_driver uas_driver = {
754	.name = "uas",
755	.probe = uas_probe,
756	.disconnect = uas_disconnect,
757	.pre_reset = uas_pre_reset,
758	.post_reset = uas_post_reset,
759	.id_table = uas_usb_ids,
760};
761
762static int uas_init(void)
763{
764	return usb_register(&uas_driver);
765}
766
767static void uas_exit(void)
768{
769	usb_deregister(&uas_driver);
770}
771
772module_init(uas_init);
773module_exit(uas_exit);
774
775MODULE_LICENSE("GPL");
776MODULE_AUTHOR("Matthew Wilcox and Sarah Sharp");
v3.5.6
  1/*
  2 * USB Attached SCSI
  3 * Note that this is not the same as the USB Mass Storage driver
  4 *
  5 * Copyright Matthew Wilcox for Intel Corp, 2010
  6 * Copyright Sarah Sharp for Intel Corp, 2010
  7 *
  8 * Distributed under the terms of the GNU GPL, version two.
  9 */
 10
 11#include <linux/blkdev.h>
 12#include <linux/slab.h>
 13#include <linux/types.h>
 14#include <linux/module.h>
 15#include <linux/usb.h>
 16#include <linux/usb/hcd.h>
 17#include <linux/usb/storage.h>
 18#include <linux/usb/uas.h>
 19
 20#include <scsi/scsi.h>
 21#include <scsi/scsi_dbg.h>
 22#include <scsi/scsi_cmnd.h>
 23#include <scsi/scsi_device.h>
 24#include <scsi/scsi_host.h>
 25#include <scsi/scsi_tcq.h>
 26
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 27/*
 28 * The r00-r01c specs define this version of the SENSE IU data structure.
 29 * It's still in use by several different firmware releases.
 30 */
 31struct sense_iu_old {
 32	__u8 iu_id;
 33	__u8 rsvd1;
 34	__be16 tag;
 35	__be16 len;
 36	__u8 status;
 37	__u8 service_response;
 38	__u8 sense[SCSI_SENSE_BUFFERSIZE];
 39};
 40
 
 
 
 
 
 
 
 
 
 
 
 
 41struct uas_dev_info {
 42	struct usb_interface *intf;
 43	struct usb_device *udev;
 44	int qdepth;
 45	unsigned cmd_pipe, status_pipe, data_in_pipe, data_out_pipe;
 46	unsigned use_streams:1;
 47	unsigned uas_sense_old:1;
 48	struct scsi_cmnd *cmnd;
 49	struct urb *status_urb; /* used only if stream support is available */
 50};
 51
 52enum {
 53	ALLOC_STATUS_URB	= (1 << 0),
 54	SUBMIT_STATUS_URB	= (1 << 1),
 55	ALLOC_DATA_IN_URB	= (1 << 2),
 56	SUBMIT_DATA_IN_URB	= (1 << 3),
 57	ALLOC_DATA_OUT_URB	= (1 << 4),
 58	SUBMIT_DATA_OUT_URB	= (1 << 5),
 59	ALLOC_CMD_URB		= (1 << 6),
 60	SUBMIT_CMD_URB		= (1 << 7),
 61};
 62
 63/* Overrides scsi_pointer */
 64struct uas_cmd_info {
 65	unsigned int state;
 66	unsigned int stream;
 67	struct urb *cmd_urb;
 68	/* status_urb is used only if stream support isn't available */
 69	struct urb *status_urb;
 70	struct urb *data_in_urb;
 71	struct urb *data_out_urb;
 72	struct list_head list;
 73};
 74
 75/* I hate forward declarations, but I actually have a loop */
 76static int uas_submit_urbs(struct scsi_cmnd *cmnd,
 77				struct uas_dev_info *devinfo, gfp_t gfp);
 78static void uas_do_work(struct work_struct *work);
 79
 80static DECLARE_WORK(uas_work, uas_do_work);
 81static DEFINE_SPINLOCK(uas_work_lock);
 82static LIST_HEAD(uas_work_list);
 83
 84static void uas_do_work(struct work_struct *work)
 85{
 86	struct uas_cmd_info *cmdinfo;
 87	struct uas_cmd_info *temp;
 88	struct list_head list;
 89	int err;
 90
 91	spin_lock_irq(&uas_work_lock);
 92	list_replace_init(&uas_work_list, &list);
 93	spin_unlock_irq(&uas_work_lock);
 94
 95	list_for_each_entry_safe(cmdinfo, temp, &list, list) {
 96		struct scsi_pointer *scp = (void *)cmdinfo;
 97		struct scsi_cmnd *cmnd = container_of(scp,
 98							struct scsi_cmnd, SCp);
 99		err = uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_NOIO);
100		if (err) {
101			list_del(&cmdinfo->list);
102			spin_lock_irq(&uas_work_lock);
103			list_add_tail(&cmdinfo->list, &uas_work_list);
104			spin_unlock_irq(&uas_work_lock);
105			schedule_work(&uas_work);
106		}
107	}
108}
109
 
 
110static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
111{
112	struct sense_iu *sense_iu = urb->transfer_buffer;
113	struct scsi_device *sdev = cmnd->device;
114
115	if (urb->actual_length > 16) {
116		unsigned len = be16_to_cpup(&sense_iu->len);
117		if (len + 16 != urb->actual_length) {
118			int newlen = min(len + 16, urb->actual_length) - 16;
119			if (newlen < 0)
120				newlen = 0;
121			sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
122				"disagrees with IU sense data length %d, "
123				"using %d bytes of sense data\n", __func__,
124					urb->actual_length, len, newlen);
125			len = newlen;
126		}
127		memcpy(cmnd->sense_buffer, sense_iu->sense, len);
128	}
129
130	cmnd->result = sense_iu->status;
 
 
131	cmnd->scsi_done(cmnd);
 
132}
133
134static void uas_sense_old(struct urb *urb, struct scsi_cmnd *cmnd)
135{
136	struct sense_iu_old *sense_iu = urb->transfer_buffer;
137	struct scsi_device *sdev = cmnd->device;
138
139	if (urb->actual_length > 8) {
140		unsigned len = be16_to_cpup(&sense_iu->len) - 2;
141		if (len + 8 != urb->actual_length) {
142			int newlen = min(len + 8, urb->actual_length) - 8;
143			if (newlen < 0)
144				newlen = 0;
145			sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
146				"disagrees with IU sense data length %d, "
147				"using %d bytes of sense data\n", __func__,
148					urb->actual_length, len, newlen);
149			len = newlen;
150		}
151		memcpy(cmnd->sense_buffer, sense_iu->sense, len);
152	}
153
154	cmnd->result = sense_iu->status;
 
 
155	cmnd->scsi_done(cmnd);
 
156}
157
158static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
159							unsigned direction)
160{
161	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
162	int err;
163
164	cmdinfo->state = direction;
165	err = uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_ATOMIC);
166	if (err) {
167		spin_lock(&uas_work_lock);
168		list_add_tail(&cmdinfo->list, &uas_work_list);
169		spin_unlock(&uas_work_lock);
170		schedule_work(&uas_work);
171	}
172}
173
174static void uas_stat_cmplt(struct urb *urb)
175{
176	struct iu *iu = urb->transfer_buffer;
177	struct Scsi_Host *shost = urb->context;
178	struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
179	struct scsi_cmnd *cmnd;
180	u16 tag;
181	int ret;
182
183	if (urb->status) {
184		dev_err(&urb->dev->dev, "URB BAD STATUS %d\n", urb->status);
185		if (devinfo->use_streams)
186			usb_free_urb(urb);
187		return;
188	}
189
190	tag = be16_to_cpup(&iu->tag) - 1;
191	if (tag == 0)
192		cmnd = devinfo->cmnd;
193	else
194		cmnd = scsi_host_find_tag(shost, tag - 1);
195	if (!cmnd) {
196		if (devinfo->use_streams) {
197			usb_free_urb(urb);
198			return;
199		}
200		ret = usb_submit_urb(urb, GFP_ATOMIC);
201		if (ret)
202			dev_err(&urb->dev->dev, "failed submit status urb\n");
203		return;
204	}
205
206	switch (iu->iu_id) {
207	case IU_ID_STATUS:
208		if (devinfo->cmnd == cmnd)
209			devinfo->cmnd = NULL;
210
211		if (urb->actual_length < 16)
212			devinfo->uas_sense_old = 1;
213		if (devinfo->uas_sense_old)
214			uas_sense_old(urb, cmnd);
215		else
216			uas_sense(urb, cmnd);
217		break;
218	case IU_ID_READ_READY:
219		uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
220		break;
221	case IU_ID_WRITE_READY:
222		uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
223		break;
224	default:
225		scmd_printk(KERN_ERR, cmnd,
226			"Bogus IU (%d) received on status pipe\n", iu->iu_id);
227	}
228
229	if (devinfo->use_streams) {
230		usb_free_urb(urb);
231		return;
232	}
233
234	ret = usb_submit_urb(urb, GFP_ATOMIC);
235	if (ret)
236		dev_err(&urb->dev->dev, "failed submit status urb\n");
237}
238
239static void uas_data_cmplt(struct urb *urb)
240{
241	struct scsi_data_buffer *sdb = urb->context;
242	sdb->resid = sdb->length - urb->actual_length;
243	usb_free_urb(urb);
244}
245
246static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
247				unsigned int pipe, u16 stream_id,
248				struct scsi_data_buffer *sdb,
249				enum dma_data_direction dir)
250{
251	struct usb_device *udev = devinfo->udev;
252	struct urb *urb = usb_alloc_urb(0, gfp);
253
254	if (!urb)
255		goto out;
256	usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length, uas_data_cmplt,
257									sdb);
258	if (devinfo->use_streams)
259		urb->stream_id = stream_id;
260	urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
261	urb->sg = sdb->table.sgl;
262 out:
263	return urb;
264}
265
266static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
267		struct Scsi_Host *shost, u16 stream_id)
268{
269	struct usb_device *udev = devinfo->udev;
270	struct urb *urb = usb_alloc_urb(0, gfp);
271	struct sense_iu *iu;
272
273	if (!urb)
274		goto out;
275
276	iu = kzalloc(sizeof(*iu), gfp);
277	if (!iu)
278		goto free;
279
280	usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
281						uas_stat_cmplt, shost);
282	urb->stream_id = stream_id;
283	urb->transfer_flags |= URB_FREE_BUFFER;
284 out:
285	return urb;
286 free:
287	usb_free_urb(urb);
288	return NULL;
289}
290
291static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
292					struct scsi_cmnd *cmnd, u16 stream_id)
293{
294	struct usb_device *udev = devinfo->udev;
295	struct scsi_device *sdev = cmnd->device;
296	struct urb *urb = usb_alloc_urb(0, gfp);
297	struct command_iu *iu;
298	int len;
299
300	if (!urb)
301		goto out;
302
303	len = cmnd->cmd_len - 16;
304	if (len < 0)
305		len = 0;
306	len = ALIGN(len, 4);
307	iu = kzalloc(sizeof(*iu) + len, gfp);
308	if (!iu)
309		goto free;
310
311	iu->iu_id = IU_ID_COMMAND;
312	if (blk_rq_tagged(cmnd->request))
313		iu->tag = cpu_to_be16(cmnd->request->tag + 2);
314	else
315		iu->tag = cpu_to_be16(1);
316	iu->prio_attr = UAS_SIMPLE_TAG;
317	iu->len = len;
318	int_to_scsilun(sdev->lun, &iu->lun);
319	memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);
320
321	usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
322							usb_free_urb, NULL);
323	urb->transfer_flags |= URB_FREE_BUFFER;
324 out:
325	return urb;
326 free:
327	usb_free_urb(urb);
328	return NULL;
329}
330
331/*
332 * Why should I request the Status IU before sending the Command IU?  Spec
333 * says to, but also says the device may receive them in any order.  Seems
334 * daft to me.
335 */
336
337static int uas_submit_urbs(struct scsi_cmnd *cmnd,
338					struct uas_dev_info *devinfo, gfp_t gfp)
339{
340	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
341
342	if (cmdinfo->state & ALLOC_STATUS_URB) {
343		cmdinfo->status_urb = uas_alloc_sense_urb(devinfo, gfp,
344				cmnd->device->host, cmdinfo->stream);
345		if (!cmdinfo->status_urb)
346			return SCSI_MLQUEUE_DEVICE_BUSY;
347		cmdinfo->state &= ~ALLOC_STATUS_URB;
348	}
349
350	if (cmdinfo->state & SUBMIT_STATUS_URB) {
351		if (usb_submit_urb(cmdinfo->status_urb, gfp)) {
352			scmd_printk(KERN_INFO, cmnd,
353					"sense urb submission failure\n");
354			return SCSI_MLQUEUE_DEVICE_BUSY;
355		}
356		cmdinfo->state &= ~SUBMIT_STATUS_URB;
357	}
358
359	if (cmdinfo->state & ALLOC_DATA_IN_URB) {
360		cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, gfp,
361					devinfo->data_in_pipe, cmdinfo->stream,
362					scsi_in(cmnd), DMA_FROM_DEVICE);
363		if (!cmdinfo->data_in_urb)
364			return SCSI_MLQUEUE_DEVICE_BUSY;
365		cmdinfo->state &= ~ALLOC_DATA_IN_URB;
366	}
367
368	if (cmdinfo->state & SUBMIT_DATA_IN_URB) {
369		if (usb_submit_urb(cmdinfo->data_in_urb, gfp)) {
370			scmd_printk(KERN_INFO, cmnd,
371					"data in urb submission failure\n");
372			return SCSI_MLQUEUE_DEVICE_BUSY;
373		}
374		cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
375	}
376
377	if (cmdinfo->state & ALLOC_DATA_OUT_URB) {
378		cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, gfp,
379					devinfo->data_out_pipe, cmdinfo->stream,
380					scsi_out(cmnd), DMA_TO_DEVICE);
381		if (!cmdinfo->data_out_urb)
382			return SCSI_MLQUEUE_DEVICE_BUSY;
383		cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
384	}
385
386	if (cmdinfo->state & SUBMIT_DATA_OUT_URB) {
387		if (usb_submit_urb(cmdinfo->data_out_urb, gfp)) {
388			scmd_printk(KERN_INFO, cmnd,
389					"data out urb submission failure\n");
390			return SCSI_MLQUEUE_DEVICE_BUSY;
391		}
392		cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
393	}
394
395	if (cmdinfo->state & ALLOC_CMD_URB) {
396		cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, gfp, cmnd,
397							cmdinfo->stream);
398		if (!cmdinfo->cmd_urb)
399			return SCSI_MLQUEUE_DEVICE_BUSY;
400		cmdinfo->state &= ~ALLOC_CMD_URB;
401	}
402
403	if (cmdinfo->state & SUBMIT_CMD_URB) {
404		if (usb_submit_urb(cmdinfo->cmd_urb, gfp)) {
405			scmd_printk(KERN_INFO, cmnd,
406					"cmd urb submission failure\n");
407			return SCSI_MLQUEUE_DEVICE_BUSY;
408		}
409		cmdinfo->state &= ~SUBMIT_CMD_URB;
410	}
411
412	return 0;
413}
414
415static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
416					void (*done)(struct scsi_cmnd *))
417{
418	struct scsi_device *sdev = cmnd->device;
419	struct uas_dev_info *devinfo = sdev->hostdata;
420	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
421	int err;
422
423	BUILD_BUG_ON(sizeof(struct uas_cmd_info) > sizeof(struct scsi_pointer));
424
425	if (devinfo->cmnd)
426		return SCSI_MLQUEUE_DEVICE_BUSY;
427
428	if (blk_rq_tagged(cmnd->request)) {
429		cmdinfo->stream = cmnd->request->tag + 2;
430	} else {
431		devinfo->cmnd = cmnd;
432		cmdinfo->stream = 1;
433	}
434
435	cmnd->scsi_done = done;
436
437	cmdinfo->state = ALLOC_STATUS_URB | SUBMIT_STATUS_URB |
438			ALLOC_CMD_URB | SUBMIT_CMD_URB;
439
440	switch (cmnd->sc_data_direction) {
441	case DMA_FROM_DEVICE:
442		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
443		break;
444	case DMA_BIDIRECTIONAL:
445		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
446	case DMA_TO_DEVICE:
447		cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
448	case DMA_NONE:
449		break;
450	}
451
452	if (!devinfo->use_streams) {
453		cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB |
454				ALLOC_STATUS_URB | SUBMIT_STATUS_URB);
455		cmdinfo->stream = 0;
456	}
457
458	err = uas_submit_urbs(cmnd, devinfo, GFP_ATOMIC);
459	if (err) {
460		/* If we did nothing, give up now */
461		if (cmdinfo->state & SUBMIT_STATUS_URB) {
462			usb_free_urb(cmdinfo->status_urb);
463			return SCSI_MLQUEUE_DEVICE_BUSY;
464		}
465		spin_lock(&uas_work_lock);
466		list_add_tail(&cmdinfo->list, &uas_work_list);
467		spin_unlock(&uas_work_lock);
468		schedule_work(&uas_work);
469	}
470
471	return 0;
472}
473
474static DEF_SCSI_QCMD(uas_queuecommand)
475
476static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
477{
478	struct scsi_device *sdev = cmnd->device;
479	sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
480							cmnd->request->tag);
481
482/* XXX: Send ABORT TASK Task Management command */
483	return FAILED;
484}
485
486static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
487{
488	struct scsi_device *sdev = cmnd->device;
489	sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
490							cmnd->request->tag);
491
492/* XXX: Send LOGICAL UNIT RESET Task Management command */
493	return FAILED;
494}
495
496static int uas_eh_target_reset_handler(struct scsi_cmnd *cmnd)
497{
498	struct scsi_device *sdev = cmnd->device;
499	sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
500							cmnd->request->tag);
501
502/* XXX: Can we reset just the one USB interface?
503 * Would calling usb_set_interface() have the right effect?
504 */
505	return FAILED;
506}
507
508static int uas_eh_bus_reset_handler(struct scsi_cmnd *cmnd)
509{
510	struct scsi_device *sdev = cmnd->device;
511	struct uas_dev_info *devinfo = sdev->hostdata;
512	struct usb_device *udev = devinfo->udev;
513
514	sdev_printk(KERN_INFO, sdev, "%s tag %d\n", __func__,
515							cmnd->request->tag);
516
517	if (usb_reset_device(udev))
518		return SUCCESS;
519
520	return FAILED;
521}
522
523static int uas_slave_alloc(struct scsi_device *sdev)
524{
525	sdev->hostdata = (void *)sdev->host->hostdata[0];
526	return 0;
527}
528
529static int uas_slave_configure(struct scsi_device *sdev)
530{
531	struct uas_dev_info *devinfo = sdev->hostdata;
532	scsi_set_tag_type(sdev, MSG_ORDERED_TAG);
533	scsi_activate_tcq(sdev, devinfo->qdepth - 2);
534	return 0;
535}
536
537static struct scsi_host_template uas_host_template = {
538	.module = THIS_MODULE,
539	.name = "uas",
540	.queuecommand = uas_queuecommand,
541	.slave_alloc = uas_slave_alloc,
542	.slave_configure = uas_slave_configure,
543	.eh_abort_handler = uas_eh_abort_handler,
544	.eh_device_reset_handler = uas_eh_device_reset_handler,
545	.eh_target_reset_handler = uas_eh_target_reset_handler,
546	.eh_bus_reset_handler = uas_eh_bus_reset_handler,
547	.can_queue = 65536,	/* Is there a limit on the _host_ ? */
548	.this_id = -1,
549	.sg_tablesize = SG_NONE,
550	.cmd_per_lun = 1,	/* until we override it */
551	.skip_settle_delay = 1,
552	.ordered_tag = 1,
553};
554
555static struct usb_device_id uas_usb_ids[] = {
556	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
557	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
558	/* 0xaa is a prototype device I happen to have access to */
559	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, 0xaa) },
560	{ }
561};
562MODULE_DEVICE_TABLE(usb, uas_usb_ids);
563
564static int uas_is_interface(struct usb_host_interface *intf)
565{
566	return (intf->desc.bInterfaceClass == USB_CLASS_MASS_STORAGE &&
567		intf->desc.bInterfaceSubClass == USB_SC_SCSI &&
568		intf->desc.bInterfaceProtocol == USB_PR_UAS);
569}
570
571static int uas_isnt_supported(struct usb_device *udev)
572{
573	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
574
575	dev_warn(&udev->dev, "The driver for the USB controller %s does not "
576			"support scatter-gather which is\n",
577			hcd->driver->description);
578	dev_warn(&udev->dev, "required by the UAS driver. Please try an"
579			"alternative USB controller if you wish to use UAS.\n");
580	return -ENODEV;
581}
582
583static int uas_switch_interface(struct usb_device *udev,
584						struct usb_interface *intf)
585{
586	int i;
587	int sg_supported = udev->bus->sg_tablesize != 0;
 
 
588
589	for (i = 0; i < intf->num_altsetting; i++) {
590		struct usb_host_interface *alt = &intf->altsetting[i];
591
592		if (uas_is_interface(alt)) {
593			if (!sg_supported)
594				return uas_isnt_supported(udev);
595			return usb_set_interface(udev,
596						alt->desc.bInterfaceNumber,
597						alt->desc.bAlternateSetting);
598		}
599	}
600
601	return -ENODEV;
602}
603
604static void uas_configure_endpoints(struct uas_dev_info *devinfo)
605{
606	struct usb_host_endpoint *eps[4] = { };
607	struct usb_interface *intf = devinfo->intf;
608	struct usb_device *udev = devinfo->udev;
609	struct usb_host_endpoint *endpoint = intf->cur_altsetting->endpoint;
610	unsigned i, n_endpoints = intf->cur_altsetting->desc.bNumEndpoints;
611
612	devinfo->uas_sense_old = 0;
613	devinfo->cmnd = NULL;
614
615	for (i = 0; i < n_endpoints; i++) {
616		unsigned char *extra = endpoint[i].extra;
617		int len = endpoint[i].extralen;
618		while (len > 1) {
619			if (extra[1] == USB_DT_PIPE_USAGE) {
620				unsigned pipe_id = extra[2];
621				if (pipe_id > 0 && pipe_id < 5)
622					eps[pipe_id - 1] = &endpoint[i];
623				break;
624			}
625			len -= extra[0];
626			extra += extra[0];
627		}
628	}
629
630	/*
631	 * Assume that if we didn't find a control pipe descriptor, we're
632	 * using a device with old firmware that happens to be set up like
633	 * this.
634	 */
635	if (!eps[0]) {
636		devinfo->cmd_pipe = usb_sndbulkpipe(udev, 1);
637		devinfo->status_pipe = usb_rcvbulkpipe(udev, 1);
638		devinfo->data_in_pipe = usb_rcvbulkpipe(udev, 2);
639		devinfo->data_out_pipe = usb_sndbulkpipe(udev, 2);
640
641		eps[1] = usb_pipe_endpoint(udev, devinfo->status_pipe);
642		eps[2] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
643		eps[3] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
644	} else {
645		devinfo->cmd_pipe = usb_sndbulkpipe(udev,
646						eps[0]->desc.bEndpointAddress);
647		devinfo->status_pipe = usb_rcvbulkpipe(udev,
648						eps[1]->desc.bEndpointAddress);
649		devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
650						eps[2]->desc.bEndpointAddress);
651		devinfo->data_out_pipe = usb_sndbulkpipe(udev,
652						eps[3]->desc.bEndpointAddress);
653	}
654
655	devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1, 3, 256,
656								GFP_KERNEL);
657	if (devinfo->qdepth < 0) {
658		devinfo->qdepth = 256;
659		devinfo->use_streams = 0;
660	} else {
661		devinfo->use_streams = 1;
662	}
663}
664
665static int uas_alloc_status_urb(struct uas_dev_info *devinfo,
666		struct Scsi_Host *shost)
667{
668	if (devinfo->use_streams) {
669		devinfo->status_urb = NULL;
670		return 0;
671	}
672
673	devinfo->status_urb = uas_alloc_sense_urb(devinfo, GFP_KERNEL,
674			shost, 0);
675	if (!devinfo->status_urb)
676		goto err_s_urb;
677
678	if (usb_submit_urb(devinfo->status_urb, GFP_KERNEL))
679		goto err_submit_urb;
680
681	return 0;
682err_submit_urb:
683	usb_free_urb(devinfo->status_urb);
684err_s_urb:
685	return -ENOMEM;
686}
687
688static void uas_free_streams(struct uas_dev_info *devinfo)
689{
690	struct usb_device *udev = devinfo->udev;
691	struct usb_host_endpoint *eps[3];
692
693	eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
694	eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
695	eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
696	usb_free_streams(devinfo->intf, eps, 3, GFP_KERNEL);
697}
698
699/*
700 * XXX: What I'd like to do here is register a SCSI host for each USB host in
701 * the system.  Follow usb-storage's design of registering a SCSI host for
702 * each USB device for the moment.  Can implement this by walking up the
703 * USB hierarchy until we find a USB host.
704 */
705static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
706{
707	int result;
708	struct Scsi_Host *shost;
709	struct uas_dev_info *devinfo;
710	struct usb_device *udev = interface_to_usbdev(intf);
711
712	if (uas_switch_interface(udev, intf))
713		return -ENODEV;
714
715	devinfo = kmalloc(sizeof(struct uas_dev_info), GFP_KERNEL);
716	if (!devinfo)
717		return -ENOMEM;
718
719	result = -ENOMEM;
720	shost = scsi_host_alloc(&uas_host_template, sizeof(void *));
721	if (!shost)
722		goto free;
723
724	shost->max_cmd_len = 16 + 252;
725	shost->max_id = 1;
726	shost->sg_tablesize = udev->bus->sg_tablesize;
727
728	devinfo->intf = intf;
729	devinfo->udev = udev;
730	uas_configure_endpoints(devinfo);
731
732	result = scsi_init_shared_tag_map(shost, devinfo->qdepth - 2);
733	if (result)
734		goto free;
735
736	result = scsi_add_host(shost, &intf->dev);
737	if (result)
738		goto deconfig_eps;
739
740	shost->hostdata[0] = (unsigned long)devinfo;
741
742	result = uas_alloc_status_urb(devinfo, shost);
743	if (result)
744		goto err_alloc_status;
745
746	scsi_scan_host(shost);
747	usb_set_intfdata(intf, shost);
748	return result;
749
750err_alloc_status:
751	scsi_remove_host(shost);
752	shost = NULL;
753deconfig_eps:
754	uas_free_streams(devinfo);
755 free:
756	kfree(devinfo);
757	if (shost)
758		scsi_host_put(shost);
759	return result;
760}
761
762static int uas_pre_reset(struct usb_interface *intf)
763{
764/* XXX: Need to return 1 if it's not our device in error handling */
765	return 0;
766}
767
768static int uas_post_reset(struct usb_interface *intf)
769{
770/* XXX: Need to return 1 if it's not our device in error handling */
771	return 0;
772}
773
774static void uas_disconnect(struct usb_interface *intf)
775{
 
 
776	struct Scsi_Host *shost = usb_get_intfdata(intf);
777	struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
778
779	scsi_remove_host(shost);
780	usb_kill_urb(devinfo->status_urb);
781	usb_free_urb(devinfo->status_urb);
782	uas_free_streams(devinfo);
 
 
 
783	kfree(devinfo);
784}
785
786/*
787 * XXX: Should this plug into libusual so we can auto-upgrade devices from
788 * Bulk-Only to UAS?
789 */
790static struct usb_driver uas_driver = {
791	.name = "uas",
792	.probe = uas_probe,
793	.disconnect = uas_disconnect,
794	.pre_reset = uas_pre_reset,
795	.post_reset = uas_post_reset,
796	.id_table = uas_usb_ids,
797};
798
799module_usb_driver(uas_driver);
 
 
 
 
 
 
 
 
 
 
 
800
801MODULE_LICENSE("GPL");
802MODULE_AUTHOR("Matthew Wilcox and Sarah Sharp");