1/*
2 * USB Attached SCSI
3 * Note that this is not the same as the USB Mass Storage driver
4 *
5 * Copyright Hans de Goede <hdegoede@redhat.com> for Red Hat, Inc. 2013 - 2016
6 * Copyright Matthew Wilcox for Intel Corp, 2010
7 * Copyright Sarah Sharp for Intel Corp, 2010
8 *
9 * Distributed under the terms of the GNU GPL, version two.
10 */
11
12#include <linux/blkdev.h>
13#include <linux/slab.h>
14#include <linux/types.h>
15#include <linux/module.h>
16#include <linux/usb.h>
17#include <linux/usb_usual.h>
18#include <linux/usb/hcd.h>
19#include <linux/usb/storage.h>
20#include <linux/usb/uas.h>
21
22#include <scsi/scsi.h>
23#include <scsi/scsi_eh.h>
24#include <scsi/scsi_dbg.h>
25#include <scsi/scsi_cmnd.h>
26#include <scsi/scsi_device.h>
27#include <scsi/scsi_host.h>
28#include <scsi/scsi_tcq.h>
29
30#include "uas-detect.h"
31#include "scsiglue.h"
32
33#define MAX_CMNDS 256
34
35struct uas_dev_info {
36	struct usb_interface *intf;
37	struct usb_device *udev;
38	struct usb_anchor cmd_urbs;
39	struct usb_anchor sense_urbs;
40	struct usb_anchor data_urbs;
41	unsigned long flags;
42	int qdepth, resetting;
43	unsigned cmd_pipe, status_pipe, data_in_pipe, data_out_pipe;
44	unsigned use_streams:1;
45	unsigned shutdown:1;
46	struct scsi_cmnd *cmnd[MAX_CMNDS];
47	spinlock_t lock;
48	struct work_struct work;
49};
50
51enum {
52	SUBMIT_STATUS_URB	= (1 << 1),
53	ALLOC_DATA_IN_URB	= (1 << 2),
54	SUBMIT_DATA_IN_URB	= (1 << 3),
55	ALLOC_DATA_OUT_URB	= (1 << 4),
56	SUBMIT_DATA_OUT_URB	= (1 << 5),
57	ALLOC_CMD_URB		= (1 << 6),
58	SUBMIT_CMD_URB		= (1 << 7),
59	COMMAND_INFLIGHT        = (1 << 8),
60	DATA_IN_URB_INFLIGHT    = (1 << 9),
61	DATA_OUT_URB_INFLIGHT   = (1 << 10),
62	COMMAND_ABORTED         = (1 << 11),
63	IS_IN_WORK_LIST         = (1 << 12),
64};
65
66/* Overrides scsi_pointer */
67struct uas_cmd_info {
68	unsigned int state;
69	unsigned int uas_tag;
70	struct urb *cmd_urb;
71	struct urb *data_in_urb;
72	struct urb *data_out_urb;
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);
79static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller);
80static void uas_free_streams(struct uas_dev_info *devinfo);
81static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
82				int status);
83
84static void uas_do_work(struct work_struct *work)
85{
86	struct uas_dev_info *devinfo =
87		container_of(work, struct uas_dev_info, work);
88	struct uas_cmd_info *cmdinfo;
89	struct scsi_cmnd *cmnd;
90	unsigned long flags;
91	int i, err;
92
93	spin_lock_irqsave(&devinfo->lock, flags);
94
95	if (devinfo->resetting)
96		goto out;
97
98	for (i = 0; i < devinfo->qdepth; i++) {
99		if (!devinfo->cmnd[i])
100			continue;
101
102		cmnd = devinfo->cmnd[i];
103		cmdinfo = (void *)&cmnd->SCp;
104
105		if (!(cmdinfo->state & IS_IN_WORK_LIST))
106			continue;
107
108		err = uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_ATOMIC);
109		if (!err)
110			cmdinfo->state &= ~IS_IN_WORK_LIST;
111		else
112			schedule_work(&devinfo->work);
113	}
114out:
115	spin_unlock_irqrestore(&devinfo->lock, flags);
116}
117
118static void uas_add_work(struct uas_cmd_info *cmdinfo)
119{
120	struct scsi_pointer *scp = (void *)cmdinfo;
121	struct scsi_cmnd *cmnd = container_of(scp, struct scsi_cmnd, SCp);
122	struct uas_dev_info *devinfo = cmnd->device->hostdata;
123
124	lockdep_assert_held(&devinfo->lock);
125	cmdinfo->state |= IS_IN_WORK_LIST;
126	schedule_work(&devinfo->work);
127}
128
129static void uas_zap_pending(struct uas_dev_info *devinfo, int result)
130{
131	struct uas_cmd_info *cmdinfo;
132	struct scsi_cmnd *cmnd;
133	unsigned long flags;
134	int i, err;
135
136	spin_lock_irqsave(&devinfo->lock, flags);
137	for (i = 0; i < devinfo->qdepth; i++) {
138		if (!devinfo->cmnd[i])
139			continue;
140
141		cmnd = devinfo->cmnd[i];
142		cmdinfo = (void *)&cmnd->SCp;
143		uas_log_cmd_state(cmnd, __func__, 0);
144		/* Sense urbs were killed, clear COMMAND_INFLIGHT manually */
145		cmdinfo->state &= ~COMMAND_INFLIGHT;
146		cmnd->result = result << 16;
147		err = uas_try_complete(cmnd, __func__);
148		WARN_ON(err != 0);
149	}
150	spin_unlock_irqrestore(&devinfo->lock, flags);
151}
152
153static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
154{
155	struct sense_iu *sense_iu = urb->transfer_buffer;
156	struct scsi_device *sdev = cmnd->device;
157
158	if (urb->actual_length > 16) {
159		unsigned len = be16_to_cpup(&sense_iu->len);
160		if (len + 16 != urb->actual_length) {
161			int newlen = min(len + 16, urb->actual_length) - 16;
162			if (newlen < 0)
163				newlen = 0;
164			sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
165				"disagrees with IU sense data length %d, "
166				"using %d bytes of sense data\n", __func__,
167					urb->actual_length, len, newlen);
168			len = newlen;
169		}
170		memcpy(cmnd->sense_buffer, sense_iu->sense, len);
171	}
172
173	cmnd->result = sense_iu->status;
174}
175
176static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
177			      int status)
178{
179	struct uas_cmd_info *ci = (void *)&cmnd->SCp;
180	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
181
182	scmd_printk(KERN_INFO, cmnd,
183		    "%s %d uas-tag %d inflight:%s%s%s%s%s%s%s%s%s%s%s%s ",
184		    prefix, status, cmdinfo->uas_tag,
185		    (ci->state & SUBMIT_STATUS_URB)     ? " s-st"  : "",
186		    (ci->state & ALLOC_DATA_IN_URB)     ? " a-in"  : "",
187		    (ci->state & SUBMIT_DATA_IN_URB)    ? " s-in"  : "",
188		    (ci->state & ALLOC_DATA_OUT_URB)    ? " a-out" : "",
189		    (ci->state & SUBMIT_DATA_OUT_URB)   ? " s-out" : "",
190		    (ci->state & ALLOC_CMD_URB)         ? " a-cmd" : "",
191		    (ci->state & SUBMIT_CMD_URB)        ? " s-cmd" : "",
192		    (ci->state & COMMAND_INFLIGHT)      ? " CMD"   : "",
193		    (ci->state & DATA_IN_URB_INFLIGHT)  ? " IN"    : "",
194		    (ci->state & DATA_OUT_URB_INFLIGHT) ? " OUT"   : "",
195		    (ci->state & COMMAND_ABORTED)       ? " abort" : "",
196		    (ci->state & IS_IN_WORK_LIST)       ? " work"  : "");
197	scsi_print_command(cmnd);
198}
199
200static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
201{
202	struct uas_cmd_info *cmdinfo;
203
204	if (!cmnd)
205		return;
206
207	cmdinfo = (void *)&cmnd->SCp;
208
209	if (cmdinfo->state & SUBMIT_CMD_URB)
210		usb_free_urb(cmdinfo->cmd_urb);
211
212	/* data urbs may have never gotten their submit flag set */
213	if (!(cmdinfo->state & DATA_IN_URB_INFLIGHT))
214		usb_free_urb(cmdinfo->data_in_urb);
215	if (!(cmdinfo->state & DATA_OUT_URB_INFLIGHT))
216		usb_free_urb(cmdinfo->data_out_urb);
217}
218
219static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
220{
221	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
222	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
223
224	lockdep_assert_held(&devinfo->lock);
225	if (cmdinfo->state & (COMMAND_INFLIGHT |
226			      DATA_IN_URB_INFLIGHT |
227			      DATA_OUT_URB_INFLIGHT |
228			      COMMAND_ABORTED))
229		return -EBUSY;
230	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
231	uas_free_unsubmitted_urbs(cmnd);
232	cmnd->scsi_done(cmnd);
233	return 0;
234}
235
236static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
237			  unsigned direction)
238{
239	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
240	int err;
241
242	cmdinfo->state |= direction | SUBMIT_STATUS_URB;
243	err = uas_submit_urbs(cmnd, cmnd->device->hostdata, GFP_ATOMIC);
244	if (err) {
245		uas_add_work(cmdinfo);
246	}
247}
248
249static void uas_stat_cmplt(struct urb *urb)
250{
251	struct iu *iu = urb->transfer_buffer;
252	struct Scsi_Host *shost = urb->context;
253	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
254	struct urb *data_in_urb = NULL;
255	struct urb *data_out_urb = NULL;
256	struct scsi_cmnd *cmnd;
257	struct uas_cmd_info *cmdinfo;
258	unsigned long flags;
259	unsigned int idx;
260
261	spin_lock_irqsave(&devinfo->lock, flags);
262
263	if (devinfo->resetting)
264		goto out;
265
266	if (urb->status) {
267		if (urb->status != -ENOENT && urb->status != -ECONNRESET) {
268			dev_err(&urb->dev->dev, "stat urb: status %d\n",
269				urb->status);
270		}
271		goto out;
272	}
273
274	idx = be16_to_cpup(&iu->tag) - 1;
275	if (idx >= MAX_CMNDS || !devinfo->cmnd[idx]) {
276		dev_err(&urb->dev->dev,
277			"stat urb: no pending cmd for uas-tag %d\n", idx + 1);
278		goto out;
279	}
280
281	cmnd = devinfo->cmnd[idx];
282	cmdinfo = (void *)&cmnd->SCp;
283
284	if (!(cmdinfo->state & COMMAND_INFLIGHT)) {
285		uas_log_cmd_state(cmnd, "unexpected status cmplt", 0);
286		goto out;
287	}
288
289	switch (iu->iu_id) {
290	case IU_ID_STATUS:
291		uas_sense(urb, cmnd);
292		if (cmnd->result != 0) {
293			/* cancel data transfers on error */
294			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
295			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
296		}
297		cmdinfo->state &= ~COMMAND_INFLIGHT;
298		uas_try_complete(cmnd, __func__);
299		break;
300	case IU_ID_READ_READY:
301		if (!cmdinfo->data_in_urb ||
302				(cmdinfo->state & DATA_IN_URB_INFLIGHT)) {
303			uas_log_cmd_state(cmnd, "unexpected read rdy", 0);
304			break;
305		}
306		uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
307		break;
308	case IU_ID_WRITE_READY:
309		if (!cmdinfo->data_out_urb ||
310				(cmdinfo->state & DATA_OUT_URB_INFLIGHT)) {
311			uas_log_cmd_state(cmnd, "unexpected write rdy", 0);
312			break;
313		}
314		uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
315		break;
316	case IU_ID_RESPONSE:
317		uas_log_cmd_state(cmnd, "unexpected response iu",
318				  ((struct response_iu *)iu)->response_code);
319		/* Error, cancel data transfers */
320		data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
321		data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
322		cmdinfo->state &= ~COMMAND_INFLIGHT;
323		cmnd->result = DID_ERROR << 16;
324		uas_try_complete(cmnd, __func__);
325		break;
326	default:
327		uas_log_cmd_state(cmnd, "bogus IU", iu->iu_id);
328	}
329out:
330	usb_free_urb(urb);
331	spin_unlock_irqrestore(&devinfo->lock, flags);
332
333	/* Unlinking of data urbs must be done without holding the lock */
334	if (data_in_urb) {
335		usb_unlink_urb(data_in_urb);
336		usb_put_urb(data_in_urb);
337	}
338	if (data_out_urb) {
339		usb_unlink_urb(data_out_urb);
340		usb_put_urb(data_out_urb);
341	}
342}
343
344static void uas_data_cmplt(struct urb *urb)
345{
346	struct scsi_cmnd *cmnd = urb->context;
347	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
348	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
349	struct scsi_data_buffer *sdb = NULL;
350	unsigned long flags;
351
352	spin_lock_irqsave(&devinfo->lock, flags);
353
354	if (cmdinfo->data_in_urb == urb) {
355		sdb = scsi_in(cmnd);
356		cmdinfo->state &= ~DATA_IN_URB_INFLIGHT;
357		cmdinfo->data_in_urb = NULL;
358	} else if (cmdinfo->data_out_urb == urb) {
359		sdb = scsi_out(cmnd);
360		cmdinfo->state &= ~DATA_OUT_URB_INFLIGHT;
361		cmdinfo->data_out_urb = NULL;
362	}
363	if (sdb == NULL) {
364		WARN_ON_ONCE(1);
365		goto out;
366	}
367
368	if (devinfo->resetting)
369		goto out;
370
371	/* Data urbs should not complete before the cmd urb is submitted */
372	if (cmdinfo->state & SUBMIT_CMD_URB) {
373		uas_log_cmd_state(cmnd, "unexpected data cmplt", 0);
374		goto out;
375	}
376
377	if (urb->status) {
378		if (urb->status != -ENOENT && urb->status != -ECONNRESET)
379			uas_log_cmd_state(cmnd, "data cmplt err", urb->status);
380		/* error: no data transfered */
381		sdb->resid = sdb->length;
382	} else {
383		sdb->resid = sdb->length - urb->actual_length;
384	}
385	uas_try_complete(cmnd, __func__);
386out:
387	usb_free_urb(urb);
388	spin_unlock_irqrestore(&devinfo->lock, flags);
389}
390
391static void uas_cmd_cmplt(struct urb *urb)
392{
393	if (urb->status)
394		dev_err(&urb->dev->dev, "cmd cmplt err %d\n", urb->status);
395
396	usb_free_urb(urb);
397}
398
399static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
400				      struct scsi_cmnd *cmnd,
401				      enum dma_data_direction dir)
402{
403	struct usb_device *udev = devinfo->udev;
404	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
405	struct urb *urb = usb_alloc_urb(0, gfp);
406	struct scsi_data_buffer *sdb = (dir == DMA_FROM_DEVICE)
407		? scsi_in(cmnd) : scsi_out(cmnd);
408	unsigned int pipe = (dir == DMA_FROM_DEVICE)
409		? devinfo->data_in_pipe : devinfo->data_out_pipe;
410
411	if (!urb)
412		goto out;
413	usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length,
414			  uas_data_cmplt, cmnd);
415	if (devinfo->use_streams)
416		urb->stream_id = cmdinfo->uas_tag;
417	urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
418	urb->sg = sdb->table.sgl;
419 out:
420	return urb;
421}
422
423static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
424				       struct scsi_cmnd *cmnd)
425{
426	struct usb_device *udev = devinfo->udev;
427	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
428	struct urb *urb = usb_alloc_urb(0, gfp);
429	struct sense_iu *iu;
430
431	if (!urb)
432		goto out;
433
434	iu = kzalloc(sizeof(*iu), gfp);
435	if (!iu)
436		goto free;
437
438	usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
439			  uas_stat_cmplt, cmnd->device->host);
440	if (devinfo->use_streams)
441		urb->stream_id = cmdinfo->uas_tag;
442	urb->transfer_flags |= URB_FREE_BUFFER;
443 out:
444	return urb;
445 free:
446	usb_free_urb(urb);
447	return NULL;
448}
449
450static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
451					struct scsi_cmnd *cmnd)
452{
453	struct usb_device *udev = devinfo->udev;
454	struct scsi_device *sdev = cmnd->device;
455	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
456	struct urb *urb = usb_alloc_urb(0, gfp);
457	struct command_iu *iu;
458	int len;
459
460	if (!urb)
461		goto out;
462
463	len = cmnd->cmd_len - 16;
464	if (len < 0)
465		len = 0;
466	len = ALIGN(len, 4);
467	iu = kzalloc(sizeof(*iu) + len, gfp);
468	if (!iu)
469		goto free;
470
471	iu->iu_id = IU_ID_COMMAND;
472	iu->tag = cpu_to_be16(cmdinfo->uas_tag);
473	iu->prio_attr = UAS_SIMPLE_TAG;
474	iu->len = len;
475	int_to_scsilun(sdev->lun, &iu->lun);
476	memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);
477
478	usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
479							uas_cmd_cmplt, NULL);
480	urb->transfer_flags |= URB_FREE_BUFFER;
481 out:
482	return urb;
483 free:
484	usb_free_urb(urb);
485	return NULL;
486}
487
488/*
489 * Why should I request the Status IU before sending the Command IU?  Spec
490 * says to, but also says the device may receive them in any order.  Seems
491 * daft to me.
492 */
493
494static struct urb *uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
495{
496	struct uas_dev_info *devinfo = cmnd->device->hostdata;
497	struct urb *urb;
498	int err;
499
500	urb = uas_alloc_sense_urb(devinfo, gfp, cmnd);
501	if (!urb)
502		return NULL;
503	usb_anchor_urb(urb, &devinfo->sense_urbs);
504	err = usb_submit_urb(urb, gfp);
505	if (err) {
506		usb_unanchor_urb(urb);
507		uas_log_cmd_state(cmnd, "sense submit err", err);
508		usb_free_urb(urb);
509		return NULL;
510	}
511	return urb;
512}
513
514static int uas_submit_urbs(struct scsi_cmnd *cmnd,
515			   struct uas_dev_info *devinfo, gfp_t gfp)
516{
517	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
518	struct urb *urb;
519	int err;
520
521	lockdep_assert_held(&devinfo->lock);
522	if (cmdinfo->state & SUBMIT_STATUS_URB) {
523		urb = uas_submit_sense_urb(cmnd, gfp);
524		if (!urb)
525			return SCSI_MLQUEUE_DEVICE_BUSY;
526		cmdinfo->state &= ~SUBMIT_STATUS_URB;
527	}
528
529	if (cmdinfo->state & ALLOC_DATA_IN_URB) {
530		cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, gfp,
531							cmnd, DMA_FROM_DEVICE);
532		if (!cmdinfo->data_in_urb)
533			return SCSI_MLQUEUE_DEVICE_BUSY;
534		cmdinfo->state &= ~ALLOC_DATA_IN_URB;
535	}
536
537	if (cmdinfo->state & SUBMIT_DATA_IN_URB) {
538		usb_anchor_urb(cmdinfo->data_in_urb, &devinfo->data_urbs);
539		err = usb_submit_urb(cmdinfo->data_in_urb, gfp);
540		if (err) {
541			usb_unanchor_urb(cmdinfo->data_in_urb);
542			uas_log_cmd_state(cmnd, "data in submit err", err);
543			return SCSI_MLQUEUE_DEVICE_BUSY;
544		}
545		cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
546		cmdinfo->state |= DATA_IN_URB_INFLIGHT;
547	}
548
549	if (cmdinfo->state & ALLOC_DATA_OUT_URB) {
550		cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, gfp,
551							cmnd, DMA_TO_DEVICE);
552		if (!cmdinfo->data_out_urb)
553			return SCSI_MLQUEUE_DEVICE_BUSY;
554		cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
555	}
556
557	if (cmdinfo->state & SUBMIT_DATA_OUT_URB) {
558		usb_anchor_urb(cmdinfo->data_out_urb, &devinfo->data_urbs);
559		err = usb_submit_urb(cmdinfo->data_out_urb, gfp);
560		if (err) {
561			usb_unanchor_urb(cmdinfo->data_out_urb);
562			uas_log_cmd_state(cmnd, "data out submit err", err);
563			return SCSI_MLQUEUE_DEVICE_BUSY;
564		}
565		cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
566		cmdinfo->state |= DATA_OUT_URB_INFLIGHT;
567	}
568
569	if (cmdinfo->state & ALLOC_CMD_URB) {
570		cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, gfp, cmnd);
571		if (!cmdinfo->cmd_urb)
572			return SCSI_MLQUEUE_DEVICE_BUSY;
573		cmdinfo->state &= ~ALLOC_CMD_URB;
574	}
575
576	if (cmdinfo->state & SUBMIT_CMD_URB) {
577		usb_anchor_urb(cmdinfo->cmd_urb, &devinfo->cmd_urbs);
578		err = usb_submit_urb(cmdinfo->cmd_urb, gfp);
579		if (err) {
580			usb_unanchor_urb(cmdinfo->cmd_urb);
581			uas_log_cmd_state(cmnd, "cmd submit err", err);
582			return SCSI_MLQUEUE_DEVICE_BUSY;
583		}
584		cmdinfo->cmd_urb = NULL;
585		cmdinfo->state &= ~SUBMIT_CMD_URB;
586		cmdinfo->state |= COMMAND_INFLIGHT;
587	}
588
589	return 0;
590}
591
592static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
593					void (*done)(struct scsi_cmnd *))
594{
595	struct scsi_device *sdev = cmnd->device;
596	struct uas_dev_info *devinfo = sdev->hostdata;
597	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
598	unsigned long flags;
599	int idx, err;
600
601	BUILD_BUG_ON(sizeof(struct uas_cmd_info) > sizeof(struct scsi_pointer));
602
603	/* Re-check scsi_block_requests now that we've the host-lock */
604	if (cmnd->device->host->host_self_blocked)
605		return SCSI_MLQUEUE_DEVICE_BUSY;
606
607	if ((devinfo->flags & US_FL_NO_ATA_1X) &&
608			(cmnd->cmnd[0] == ATA_12 || cmnd->cmnd[0] == ATA_16)) {
609		memcpy(cmnd->sense_buffer, usb_stor_sense_invalidCDB,
610		       sizeof(usb_stor_sense_invalidCDB));
611		cmnd->result = SAM_STAT_CHECK_CONDITION;
612		cmnd->scsi_done(cmnd);
613		return 0;
614	}
615
616	spin_lock_irqsave(&devinfo->lock, flags);
617
618	if (devinfo->resetting) {
619		cmnd->result = DID_ERROR << 16;
620		cmnd->scsi_done(cmnd);
621		spin_unlock_irqrestore(&devinfo->lock, flags);
622		return 0;
623	}
624
625	/* Find a free uas-tag */
626	for (idx = 0; idx < devinfo->qdepth; idx++) {
627		if (!devinfo->cmnd[idx])
628			break;
629	}
630	if (idx == devinfo->qdepth) {
631		spin_unlock_irqrestore(&devinfo->lock, flags);
632		return SCSI_MLQUEUE_DEVICE_BUSY;
633	}
634
635	cmnd->scsi_done = done;
636
637	memset(cmdinfo, 0, sizeof(*cmdinfo));
638	cmdinfo->uas_tag = idx + 1; /* uas-tag == usb-stream-id, so 1 based */
639	cmdinfo->state = SUBMIT_STATUS_URB | ALLOC_CMD_URB | SUBMIT_CMD_URB;
640
641	switch (cmnd->sc_data_direction) {
642	case DMA_FROM_DEVICE:
643		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
644		break;
645	case DMA_BIDIRECTIONAL:
646		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
647	case DMA_TO_DEVICE:
648		cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
649	case DMA_NONE:
650		break;
651	}
652
653	if (!devinfo->use_streams)
654		cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
655
656	err = uas_submit_urbs(cmnd, devinfo, GFP_ATOMIC);
657	if (err) {
658		/* If we did nothing, give up now */
659		if (cmdinfo->state & SUBMIT_STATUS_URB) {
660			spin_unlock_irqrestore(&devinfo->lock, flags);
661			return SCSI_MLQUEUE_DEVICE_BUSY;
662		}
663		uas_add_work(cmdinfo);
664	}
665
666	devinfo->cmnd[idx] = cmnd;
667	spin_unlock_irqrestore(&devinfo->lock, flags);
668	return 0;
669}
670
671static DEF_SCSI_QCMD(uas_queuecommand)
672
673/*
674 * For now we do not support actually sending an abort to the device, so
675 * this eh always fails. Still we must define it to make sure that we've
676 * dropped all references to the cmnd in question once this function exits.
677 */
678static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
679{
680	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
681	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
682	struct urb *data_in_urb = NULL;
683	struct urb *data_out_urb = NULL;
684	unsigned long flags;
685
686	spin_lock_irqsave(&devinfo->lock, flags);
687
688	uas_log_cmd_state(cmnd, __func__, 0);
689
690	/* Ensure that try_complete does not call scsi_done */
691	cmdinfo->state |= COMMAND_ABORTED;
692
693	/* Drop all refs to this cmnd, kill data urbs to break their ref */
694	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
695	if (cmdinfo->state & DATA_IN_URB_INFLIGHT)
696		data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
697	if (cmdinfo->state & DATA_OUT_URB_INFLIGHT)
698		data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
699
700	uas_free_unsubmitted_urbs(cmnd);
701
702	spin_unlock_irqrestore(&devinfo->lock, flags);
703
704	if (data_in_urb) {
705		usb_kill_urb(data_in_urb);
706		usb_put_urb(data_in_urb);
707	}
708	if (data_out_urb) {
709		usb_kill_urb(data_out_urb);
710		usb_put_urb(data_out_urb);
711	}
712
713	return FAILED;
714}
715
716static int uas_eh_bus_reset_handler(struct scsi_cmnd *cmnd)
717{
718	struct scsi_device *sdev = cmnd->device;
719	struct uas_dev_info *devinfo = sdev->hostdata;
720	struct usb_device *udev = devinfo->udev;
721	unsigned long flags;
722	int err;
723
724	err = usb_lock_device_for_reset(udev, devinfo->intf);
725	if (err) {
726		shost_printk(KERN_ERR, sdev->host,
727			     "%s FAILED to get lock err %d\n", __func__, err);
728		return FAILED;
729	}
730
731	shost_printk(KERN_INFO, sdev->host, "%s start\n", __func__);
732
733	spin_lock_irqsave(&devinfo->lock, flags);
734	devinfo->resetting = 1;
735	spin_unlock_irqrestore(&devinfo->lock, flags);
736
737	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
738	usb_kill_anchored_urbs(&devinfo->sense_urbs);
739	usb_kill_anchored_urbs(&devinfo->data_urbs);
740	uas_zap_pending(devinfo, DID_RESET);
741
742	err = usb_reset_device(udev);
743
744	spin_lock_irqsave(&devinfo->lock, flags);
745	devinfo->resetting = 0;
746	spin_unlock_irqrestore(&devinfo->lock, flags);
747
748	usb_unlock_device(udev);
749
750	if (err) {
751		shost_printk(KERN_INFO, sdev->host, "%s FAILED err %d\n",
752			     __func__, err);
753		return FAILED;
754	}
755
756	shost_printk(KERN_INFO, sdev->host, "%s success\n", __func__);
757	return SUCCESS;
758}
759
760static int uas_target_alloc(struct scsi_target *starget)
761{
762	struct uas_dev_info *devinfo = (struct uas_dev_info *)
763			dev_to_shost(starget->dev.parent)->hostdata;
764
765	if (devinfo->flags & US_FL_NO_REPORT_LUNS)
766		starget->no_report_luns = 1;
767
768	return 0;
769}
770
771static int uas_slave_alloc(struct scsi_device *sdev)
772{
773	struct uas_dev_info *devinfo =
774		(struct uas_dev_info *)sdev->host->hostdata;
775
776	sdev->hostdata = devinfo;
777
778	/* USB has unusual DMA-alignment requirements: Although the
779	 * starting address of each scatter-gather element doesn't matter,
780	 * the length of each element except the last must be divisible
781	 * by the Bulk maxpacket value.  There's currently no way to
782	 * express this by block-layer constraints, so we'll cop out
783	 * and simply require addresses to be aligned at 512-byte
784	 * boundaries.  This is okay since most block I/O involves
785	 * hardware sectors that are multiples of 512 bytes in length,
786	 * and since host controllers up through USB 2.0 have maxpacket
787	 * values no larger than 512.
788	 *
789	 * But it doesn't suffice for Wireless USB, where Bulk maxpacket
790	 * values can be as large as 2048.  To make that work properly
791	 * will require changes to the block layer.
792	 */
793	blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
794
795	if (devinfo->flags & US_FL_MAX_SECTORS_64)
796		blk_queue_max_hw_sectors(sdev->request_queue, 64);
797	else if (devinfo->flags & US_FL_MAX_SECTORS_240)
798		blk_queue_max_hw_sectors(sdev->request_queue, 240);
799
800	return 0;
801}
802
803static int uas_slave_configure(struct scsi_device *sdev)
804{
805	struct uas_dev_info *devinfo = sdev->hostdata;
806
807	if (devinfo->flags & US_FL_NO_REPORT_OPCODES)
808		sdev->no_report_opcodes = 1;
809
810	/* A few buggy USB-ATA bridges don't understand FUA */
811	if (devinfo->flags & US_FL_BROKEN_FUA)
812		sdev->broken_fua = 1;
813
814	scsi_change_queue_depth(sdev, devinfo->qdepth - 2);
815	return 0;
816}
817
818static struct scsi_host_template uas_host_template = {
819	.module = THIS_MODULE,
820	.name = "uas",
821	.queuecommand = uas_queuecommand,
822	.target_alloc = uas_target_alloc,
823	.slave_alloc = uas_slave_alloc,
824	.slave_configure = uas_slave_configure,
825	.eh_abort_handler = uas_eh_abort_handler,
826	.eh_bus_reset_handler = uas_eh_bus_reset_handler,
827	.can_queue = MAX_CMNDS,
828	.this_id = -1,
829	.sg_tablesize = SG_NONE,
830	.cmd_per_lun = 1,	/* until we override it */
831	.skip_settle_delay = 1,
832	.use_blk_tags = 1,
833};
834
835#define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
836		    vendorName, productName, useProtocol, useTransport, \
837		    initFunction, flags) \
838{ USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
839	.driver_info = (flags) }
840
841static struct usb_device_id uas_usb_ids[] = {
842#	include "unusual_uas.h"
843	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
844	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
845	{ }
846};
847MODULE_DEVICE_TABLE(usb, uas_usb_ids);
848
849#undef UNUSUAL_DEV
850
851static int uas_switch_interface(struct usb_device *udev,
852				struct usb_interface *intf)
853{
854	int alt;
855
856	alt = uas_find_uas_alt_setting(intf);
857	if (alt < 0)
858		return alt;
859
860	return usb_set_interface(udev,
861			intf->altsetting[0].desc.bInterfaceNumber, alt);
862}
863
864static int uas_configure_endpoints(struct uas_dev_info *devinfo)
865{
866	struct usb_host_endpoint *eps[4] = { };
867	struct usb_device *udev = devinfo->udev;
868	int r;
869
870	r = uas_find_endpoints(devinfo->intf->cur_altsetting, eps);
871	if (r)
872		return r;
873
874	devinfo->cmd_pipe = usb_sndbulkpipe(udev,
875					    usb_endpoint_num(&eps[0]->desc));
876	devinfo->status_pipe = usb_rcvbulkpipe(udev,
877					    usb_endpoint_num(&eps[1]->desc));
878	devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
879					    usb_endpoint_num(&eps[2]->desc));
880	devinfo->data_out_pipe = usb_sndbulkpipe(udev,
881					    usb_endpoint_num(&eps[3]->desc));
882
883	if (udev->speed < USB_SPEED_SUPER) {
884		devinfo->qdepth = 32;
885		devinfo->use_streams = 0;
886	} else {
887		devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1,
888						    3, MAX_CMNDS, GFP_NOIO);
889		if (devinfo->qdepth < 0)
890			return devinfo->qdepth;
891		devinfo->use_streams = 1;
892	}
893
894	return 0;
895}
896
897static void uas_free_streams(struct uas_dev_info *devinfo)
898{
899	struct usb_device *udev = devinfo->udev;
900	struct usb_host_endpoint *eps[3];
901
902	eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
903	eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
904	eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
905	usb_free_streams(devinfo->intf, eps, 3, GFP_NOIO);
906}
907
908static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
909{
910	int result = -ENOMEM;
911	struct Scsi_Host *shost = NULL;
912	struct uas_dev_info *devinfo;
913	struct usb_device *udev = interface_to_usbdev(intf);
914	unsigned long dev_flags;
915
916	if (!uas_use_uas_driver(intf, id, &dev_flags))
917		return -ENODEV;
918
919	if (uas_switch_interface(udev, intf))
920		return -ENODEV;
921
922	shost = scsi_host_alloc(&uas_host_template,
923				sizeof(struct uas_dev_info));
924	if (!shost)
925		goto set_alt0;
926
927	shost->max_cmd_len = 16 + 252;
928	shost->max_id = 1;
929	shost->max_lun = 256;
930	shost->max_channel = 0;
931	shost->sg_tablesize = udev->bus->sg_tablesize;
932
933	devinfo = (struct uas_dev_info *)shost->hostdata;
934	devinfo->intf = intf;
935	devinfo->udev = udev;
936	devinfo->resetting = 0;
937	devinfo->shutdown = 0;
938	devinfo->flags = dev_flags;
939	init_usb_anchor(&devinfo->cmd_urbs);
940	init_usb_anchor(&devinfo->sense_urbs);
941	init_usb_anchor(&devinfo->data_urbs);
942	spin_lock_init(&devinfo->lock);
943	INIT_WORK(&devinfo->work, uas_do_work);
944
945	result = uas_configure_endpoints(devinfo);
946	if (result)
947		goto set_alt0;
948
949	result = scsi_init_shared_tag_map(shost, devinfo->qdepth - 2);
950	if (result)
951		goto free_streams;
952
953	usb_set_intfdata(intf, shost);
954	result = scsi_add_host(shost, &intf->dev);
955	if (result)
956		goto free_streams;
957
958	scsi_scan_host(shost);
959	return result;
960
961free_streams:
962	uas_free_streams(devinfo);
963	usb_set_intfdata(intf, NULL);
964set_alt0:
965	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
966	if (shost)
967		scsi_host_put(shost);
968	return result;
969}
970
971static int uas_cmnd_list_empty(struct uas_dev_info *devinfo)
972{
973	unsigned long flags;
974	int i, r = 1;
975
976	spin_lock_irqsave(&devinfo->lock, flags);
977
978	for (i = 0; i < devinfo->qdepth; i++) {
979		if (devinfo->cmnd[i]) {
980			r = 0; /* Not empty */
981			break;
982		}
983	}
984
985	spin_unlock_irqrestore(&devinfo->lock, flags);
986
987	return r;
988}
989
990/*
991 * Wait for any pending cmnds to complete, on usb-2 sense_urbs may temporarily
992 * get empty while there still is more work to do due to sense-urbs completing
993 * with a READ/WRITE_READY iu code, so keep waiting until the list gets empty.
994 */
995static int uas_wait_for_pending_cmnds(struct uas_dev_info *devinfo)
996{
997	unsigned long start_time;
998	int r;
999
1000	start_time = jiffies;
1001	do {
1002		flush_work(&devinfo->work);
1003
1004		r = usb_wait_anchor_empty_timeout(&devinfo->sense_urbs, 5000);
1005		if (r == 0)
1006			return -ETIME;
1007
1008		r = usb_wait_anchor_empty_timeout(&devinfo->data_urbs, 500);
1009		if (r == 0)
1010			return -ETIME;
1011
1012		if (time_after(jiffies, start_time + 5 * HZ))
1013			return -ETIME;
1014	} while (!uas_cmnd_list_empty(devinfo));
1015
1016	return 0;
1017}
1018
1019static int uas_pre_reset(struct usb_interface *intf)
1020{
1021	struct Scsi_Host *shost = usb_get_intfdata(intf);
1022	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1023	unsigned long flags;
1024
1025	if (devinfo->shutdown)
1026		return 0;
1027
1028	/* Block new requests */
1029	spin_lock_irqsave(shost->host_lock, flags);
1030	scsi_block_requests(shost);
1031	spin_unlock_irqrestore(shost->host_lock, flags);
1032
1033	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1034		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1035		scsi_unblock_requests(shost);
1036		return 1;
1037	}
1038
1039	uas_free_streams(devinfo);
1040
1041	return 0;
1042}
1043
1044static int uas_post_reset(struct usb_interface *intf)
1045{
1046	struct Scsi_Host *shost = usb_get_intfdata(intf);
1047	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1048	unsigned long flags;
1049	int err;
1050
1051	if (devinfo->shutdown)
1052		return 0;
1053
1054	err = uas_configure_endpoints(devinfo);
1055	if (err) {
1056		shost_printk(KERN_ERR, shost,
1057			     "%s: alloc streams error %d after reset",
1058			     __func__, err);
1059		return 1;
1060	}
1061
1062	spin_lock_irqsave(shost->host_lock, flags);
1063	scsi_report_bus_reset(shost, 0);
1064	spin_unlock_irqrestore(shost->host_lock, flags);
1065
1066	scsi_unblock_requests(shost);
1067
1068	return 0;
1069}
1070
1071static int uas_suspend(struct usb_interface *intf, pm_message_t message)
1072{
1073	struct Scsi_Host *shost = usb_get_intfdata(intf);
1074	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1075
1076	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1077		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1078		return -ETIME;
1079	}
1080
1081	return 0;
1082}
1083
1084static int uas_resume(struct usb_interface *intf)
1085{
1086	return 0;
1087}
1088
1089static int uas_reset_resume(struct usb_interface *intf)
1090{
1091	struct Scsi_Host *shost = usb_get_intfdata(intf);
1092	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1093	unsigned long flags;
1094	int err;
1095
1096	err = uas_configure_endpoints(devinfo);
1097	if (err) {
1098		shost_printk(KERN_ERR, shost,
1099			     "%s: alloc streams error %d after reset",
1100			     __func__, err);
1101		return -EIO;
1102	}
1103
1104	spin_lock_irqsave(shost->host_lock, flags);
1105	scsi_report_bus_reset(shost, 0);
1106	spin_unlock_irqrestore(shost->host_lock, flags);
1107
1108	return 0;
1109}
1110
1111static void uas_disconnect(struct usb_interface *intf)
1112{
1113	struct Scsi_Host *shost = usb_get_intfdata(intf);
1114	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1115	unsigned long flags;
1116
1117	spin_lock_irqsave(&devinfo->lock, flags);
1118	devinfo->resetting = 1;
1119	spin_unlock_irqrestore(&devinfo->lock, flags);
1120
1121	cancel_work_sync(&devinfo->work);
1122	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
1123	usb_kill_anchored_urbs(&devinfo->sense_urbs);
1124	usb_kill_anchored_urbs(&devinfo->data_urbs);
1125	uas_zap_pending(devinfo, DID_NO_CONNECT);
1126
1127	scsi_remove_host(shost);
1128	uas_free_streams(devinfo);
1129	scsi_host_put(shost);
1130}
1131
1132/*
1133 * Put the device back in usb-storage mode on shutdown, as some BIOS-es
1134 * hang on reboot when the device is still in uas mode. Note the reset is
1135 * necessary as some devices won't revert to usb-storage mode without it.
1136 */
1137static void uas_shutdown(struct device *dev)
1138{
1139	struct usb_interface *intf = to_usb_interface(dev);
1140	struct usb_device *udev = interface_to_usbdev(intf);
1141	struct Scsi_Host *shost = usb_get_intfdata(intf);
1142	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1143
1144	if (system_state != SYSTEM_RESTART)
1145		return;
1146
1147	devinfo->shutdown = 1;
1148	uas_free_streams(devinfo);
1149	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
1150	usb_reset_device(udev);
1151}
1152
1153static struct usb_driver uas_driver = {
1154	.name = "uas",
1155	.probe = uas_probe,
1156	.disconnect = uas_disconnect,
1157	.pre_reset = uas_pre_reset,
1158	.post_reset = uas_post_reset,
1159	.suspend = uas_suspend,
1160	.resume = uas_resume,
1161	.reset_resume = uas_reset_resume,
1162	.drvwrap.driver.shutdown = uas_shutdown,
1163	.id_table = uas_usb_ids,
1164};
1165
1166module_usb_driver(uas_driver);
1167
1168MODULE_LICENSE("GPL");
1169MODULE_AUTHOR(
1170	"Hans de Goede <hdegoede@redhat.com>, Matthew Wilcox and Sarah Sharp");
1171