xref: /openbmc/qemu/hw/usb/dev-storage.c (revision 964d0a7b2bab935d48d3b2c4d6ab9b0efc74ce8b)
1 /*
2  * USB Mass Storage Device emulation
3  *
4  * Copyright (c) 2006 CodeSourcery.
5  * Written by Paul Brook
6  *
7  * This code is licensed under the LGPL.
8  */
9 
10 #include "qemu-common.h"
11 #include "qemu-option.h"
12 #include "qemu-config.h"
13 #include "hw/usb.h"
14 #include "hw/usb/desc.h"
15 #include "hw/scsi.h"
16 #include "console.h"
17 #include "monitor.h"
18 #include "sysemu.h"
19 #include "blockdev.h"
20 
21 //#define DEBUG_MSD
22 
23 #ifdef DEBUG_MSD
24 #define DPRINTF(fmt, ...) \
25 do { printf("usb-msd: " fmt , ## __VA_ARGS__); } while (0)
26 #else
27 #define DPRINTF(fmt, ...) do {} while(0)
28 #endif
29 
30 /* USB requests.  */
31 #define MassStorageReset  0xff
32 #define GetMaxLun         0xfe
33 
34 enum USBMSDMode {
35     USB_MSDM_CBW, /* Command Block.  */
36     USB_MSDM_DATAOUT, /* Transfer data to device.  */
37     USB_MSDM_DATAIN, /* Transfer data from device.  */
38     USB_MSDM_CSW /* Command Status.  */
39 };
40 
41 struct usb_msd_csw {
42     uint32_t sig;
43     uint32_t tag;
44     uint32_t residue;
45     uint8_t status;
46 };
47 
48 typedef struct {
49     USBDevice dev;
50     enum USBMSDMode mode;
51     uint32_t scsi_off;
52     uint32_t scsi_len;
53     uint32_t data_len;
54     struct usb_msd_csw csw;
55     SCSIRequest *req;
56     SCSIBus bus;
57     BlockConf conf;
58     char *serial;
59     SCSIDevice *scsi_dev;
60     uint32_t removable;
61     /* For async completion.  */
62     USBPacket *packet;
63 } MSDState;
64 
65 struct usb_msd_cbw {
66     uint32_t sig;
67     uint32_t tag;
68     uint32_t data_len;
69     uint8_t flags;
70     uint8_t lun;
71     uint8_t cmd_len;
72     uint8_t cmd[16];
73 };
74 
75 enum {
76     STR_MANUFACTURER = 1,
77     STR_PRODUCT,
78     STR_SERIALNUMBER,
79     STR_CONFIG_FULL,
80     STR_CONFIG_HIGH,
81 };
82 
83 static const USBDescStrings desc_strings = {
84     [STR_MANUFACTURER] = "QEMU",
85     [STR_PRODUCT]      = "QEMU USB HARDDRIVE",
86     [STR_SERIALNUMBER] = "1",
87     [STR_CONFIG_FULL]  = "Full speed config (usb 1.1)",
88     [STR_CONFIG_HIGH]  = "High speed config (usb 2.0)",
89 };
90 
91 static const USBDescIface desc_iface_full = {
92     .bInterfaceNumber              = 0,
93     .bNumEndpoints                 = 2,
94     .bInterfaceClass               = USB_CLASS_MASS_STORAGE,
95     .bInterfaceSubClass            = 0x06, /* SCSI */
96     .bInterfaceProtocol            = 0x50, /* Bulk */
97     .eps = (USBDescEndpoint[]) {
98         {
99             .bEndpointAddress      = USB_DIR_IN | 0x01,
100             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
101             .wMaxPacketSize        = 64,
102         },{
103             .bEndpointAddress      = USB_DIR_OUT | 0x02,
104             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
105             .wMaxPacketSize        = 64,
106         },
107     }
108 };
109 
110 static const USBDescDevice desc_device_full = {
111     .bcdUSB                        = 0x0200,
112     .bMaxPacketSize0               = 8,
113     .bNumConfigurations            = 1,
114     .confs = (USBDescConfig[]) {
115         {
116             .bNumInterfaces        = 1,
117             .bConfigurationValue   = 1,
118             .iConfiguration        = STR_CONFIG_FULL,
119             .bmAttributes          = 0xc0,
120             .nif = 1,
121             .ifs = &desc_iface_full,
122         },
123     },
124 };
125 
126 static const USBDescIface desc_iface_high = {
127     .bInterfaceNumber              = 0,
128     .bNumEndpoints                 = 2,
129     .bInterfaceClass               = USB_CLASS_MASS_STORAGE,
130     .bInterfaceSubClass            = 0x06, /* SCSI */
131     .bInterfaceProtocol            = 0x50, /* Bulk */
132     .eps = (USBDescEndpoint[]) {
133         {
134             .bEndpointAddress      = USB_DIR_IN | 0x01,
135             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
136             .wMaxPacketSize        = 512,
137         },{
138             .bEndpointAddress      = USB_DIR_OUT | 0x02,
139             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
140             .wMaxPacketSize        = 512,
141         },
142     }
143 };
144 
145 static const USBDescDevice desc_device_high = {
146     .bcdUSB                        = 0x0200,
147     .bMaxPacketSize0               = 64,
148     .bNumConfigurations            = 1,
149     .confs = (USBDescConfig[]) {
150         {
151             .bNumInterfaces        = 1,
152             .bConfigurationValue   = 1,
153             .iConfiguration        = STR_CONFIG_HIGH,
154             .bmAttributes          = 0xc0,
155             .nif = 1,
156             .ifs = &desc_iface_high,
157         },
158     },
159 };
160 
161 static const USBDesc desc = {
162     .id = {
163         .idVendor          = 0x46f4, /* CRC16() of "QEMU" */
164         .idProduct         = 0x0001,
165         .bcdDevice         = 0,
166         .iManufacturer     = STR_MANUFACTURER,
167         .iProduct          = STR_PRODUCT,
168         .iSerialNumber     = STR_SERIALNUMBER,
169     },
170     .full = &desc_device_full,
171     .high = &desc_device_high,
172     .str  = desc_strings,
173 };
174 
175 static void usb_msd_copy_data(MSDState *s, USBPacket *p)
176 {
177     uint32_t len;
178     len = p->iov.size - p->result;
179     if (len > s->scsi_len)
180         len = s->scsi_len;
181     usb_packet_copy(p, scsi_req_get_buf(s->req) + s->scsi_off, len);
182     s->scsi_len -= len;
183     s->scsi_off += len;
184     s->data_len -= len;
185     if (s->scsi_len == 0 || s->data_len == 0) {
186         scsi_req_continue(s->req);
187     }
188 }
189 
190 static void usb_msd_send_status(MSDState *s, USBPacket *p)
191 {
192     int len;
193 
194     DPRINTF("Command status %d tag 0x%x, len %zd\n",
195             s->csw.status, le32_to_cpu(s->csw.tag), p->iov.size);
196 
197     assert(s->csw.sig == cpu_to_le32(0x53425355));
198     len = MIN(sizeof(s->csw), p->iov.size);
199     usb_packet_copy(p, &s->csw, len);
200     memset(&s->csw, 0, sizeof(s->csw));
201 }
202 
203 static void usb_msd_packet_complete(MSDState *s)
204 {
205     USBPacket *p = s->packet;
206 
207     /* Set s->packet to NULL before calling usb_packet_complete
208        because another request may be issued before
209        usb_packet_complete returns.  */
210     DPRINTF("Packet complete %p\n", p);
211     s->packet = NULL;
212     usb_packet_complete(&s->dev, p);
213 }
214 
215 static void usb_msd_transfer_data(SCSIRequest *req, uint32_t len)
216 {
217     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
218     USBPacket *p = s->packet;
219 
220     assert((s->mode == USB_MSDM_DATAOUT) == (req->cmd.mode == SCSI_XFER_TO_DEV));
221     s->scsi_len = len;
222     s->scsi_off = 0;
223     if (p) {
224         usb_msd_copy_data(s, p);
225         p = s->packet;
226         if (p && p->result == p->iov.size) {
227             usb_msd_packet_complete(s);
228         }
229     }
230 }
231 
232 static void usb_msd_command_complete(SCSIRequest *req, uint32_t status, size_t resid)
233 {
234     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
235     USBPacket *p = s->packet;
236 
237     DPRINTF("Command complete %d tag 0x%x\n", status, req->tag);
238 
239     s->csw.sig = cpu_to_le32(0x53425355);
240     s->csw.tag = cpu_to_le32(req->tag);
241     s->csw.residue = cpu_to_le32(s->data_len);
242     s->csw.status = status != 0;
243 
244     if (s->packet) {
245         if (s->data_len == 0 && s->mode == USB_MSDM_DATAOUT) {
246             /* A deferred packet with no write data remaining must be
247                the status read packet.  */
248             usb_msd_send_status(s, p);
249             s->mode = USB_MSDM_CBW;
250         } else if (s->mode == USB_MSDM_CSW) {
251             usb_msd_send_status(s, p);
252             s->mode = USB_MSDM_CBW;
253         } else {
254             if (s->data_len) {
255                 int len = (p->iov.size - p->result);
256                 usb_packet_skip(p, len);
257                 s->data_len -= len;
258             }
259             if (s->data_len == 0) {
260                 s->mode = USB_MSDM_CSW;
261             }
262         }
263         usb_msd_packet_complete(s);
264     } else if (s->data_len == 0) {
265         s->mode = USB_MSDM_CSW;
266     }
267     scsi_req_unref(req);
268     s->req = NULL;
269 }
270 
271 static void usb_msd_request_cancelled(SCSIRequest *req)
272 {
273     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
274 
275     if (req == s->req) {
276         scsi_req_unref(s->req);
277         s->req = NULL;
278         s->scsi_len = 0;
279     }
280 }
281 
282 static void usb_msd_handle_reset(USBDevice *dev)
283 {
284     MSDState *s = (MSDState *)dev;
285 
286     DPRINTF("Reset\n");
287     if (s->req) {
288         scsi_req_cancel(s->req);
289     }
290     assert(s->req == NULL);
291 
292     if (s->packet) {
293         s->packet->result = USB_RET_STALL;
294         usb_msd_packet_complete(s);
295     }
296 
297     s->mode = USB_MSDM_CBW;
298 }
299 
300 static int usb_msd_handle_control(USBDevice *dev, USBPacket *p,
301                int request, int value, int index, int length, uint8_t *data)
302 {
303     MSDState *s = (MSDState *)dev;
304     int ret;
305 
306     ret = usb_desc_handle_control(dev, p, request, value, index, length, data);
307     if (ret >= 0) {
308         return ret;
309     }
310 
311     ret = 0;
312     switch (request) {
313     case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
314         ret = 0;
315         break;
316         /* Class specific requests.  */
317     case ClassInterfaceOutRequest | MassStorageReset:
318         /* Reset state ready for the next CBW.  */
319         s->mode = USB_MSDM_CBW;
320         ret = 0;
321         break;
322     case ClassInterfaceRequest | GetMaxLun:
323         data[0] = 0;
324         ret = 1;
325         break;
326     default:
327         ret = USB_RET_STALL;
328         break;
329     }
330     return ret;
331 }
332 
333 static void usb_msd_cancel_io(USBDevice *dev, USBPacket *p)
334 {
335     MSDState *s = DO_UPCAST(MSDState, dev, dev);
336 
337     assert(s->packet == p);
338     s->packet = NULL;
339 
340     if (s->req) {
341         scsi_req_cancel(s->req);
342     }
343 }
344 
345 static int usb_msd_handle_data(USBDevice *dev, USBPacket *p)
346 {
347     MSDState *s = (MSDState *)dev;
348     uint32_t tag;
349     int ret = 0;
350     struct usb_msd_cbw cbw;
351     uint8_t devep = p->ep->nr;
352 
353     switch (p->pid) {
354     case USB_TOKEN_OUT:
355         if (devep != 2)
356             goto fail;
357 
358         switch (s->mode) {
359         case USB_MSDM_CBW:
360             if (p->iov.size != 31) {
361                 fprintf(stderr, "usb-msd: Bad CBW size");
362                 goto fail;
363             }
364             usb_packet_copy(p, &cbw, 31);
365             if (le32_to_cpu(cbw.sig) != 0x43425355) {
366                 fprintf(stderr, "usb-msd: Bad signature %08x\n",
367                         le32_to_cpu(cbw.sig));
368                 goto fail;
369             }
370             DPRINTF("Command on LUN %d\n", cbw.lun);
371             if (cbw.lun != 0) {
372                 fprintf(stderr, "usb-msd: Bad LUN %d\n", cbw.lun);
373                 goto fail;
374             }
375             tag = le32_to_cpu(cbw.tag);
376             s->data_len = le32_to_cpu(cbw.data_len);
377             if (s->data_len == 0) {
378                 s->mode = USB_MSDM_CSW;
379             } else if (cbw.flags & 0x80) {
380                 s->mode = USB_MSDM_DATAIN;
381             } else {
382                 s->mode = USB_MSDM_DATAOUT;
383             }
384             DPRINTF("Command tag 0x%x flags %08x len %d data %d\n",
385                     tag, cbw.flags, cbw.cmd_len, s->data_len);
386             assert(le32_to_cpu(s->csw.residue) == 0);
387             s->scsi_len = 0;
388             s->req = scsi_req_new(s->scsi_dev, tag, 0, cbw.cmd, NULL);
389 #ifdef DEBUG_MSD
390             scsi_req_print(s->req);
391 #endif
392             scsi_req_enqueue(s->req);
393             if (s->req && s->req->cmd.xfer != SCSI_XFER_NONE) {
394                 scsi_req_continue(s->req);
395             }
396             ret = p->result;
397             break;
398 
399         case USB_MSDM_DATAOUT:
400             DPRINTF("Data out %zd/%d\n", p->iov.size, s->data_len);
401             if (p->iov.size > s->data_len) {
402                 goto fail;
403             }
404 
405             if (s->scsi_len) {
406                 usb_msd_copy_data(s, p);
407             }
408             if (le32_to_cpu(s->csw.residue)) {
409                 int len = p->iov.size - p->result;
410                 if (len) {
411                     usb_packet_skip(p, len);
412                     s->data_len -= len;
413                     if (s->data_len == 0) {
414                         s->mode = USB_MSDM_CSW;
415                     }
416                 }
417             }
418             if (p->result < p->iov.size) {
419                 DPRINTF("Deferring packet %p [wait data-out]\n", p);
420                 s->packet = p;
421                 ret = USB_RET_ASYNC;
422             } else {
423                 ret = p->result;
424             }
425             break;
426 
427         default:
428             DPRINTF("Unexpected write (len %zd)\n", p->iov.size);
429             goto fail;
430         }
431         break;
432 
433     case USB_TOKEN_IN:
434         if (devep != 1)
435             goto fail;
436 
437         switch (s->mode) {
438         case USB_MSDM_DATAOUT:
439             if (s->data_len != 0 || p->iov.size < 13) {
440                 goto fail;
441             }
442             /* Waiting for SCSI write to complete.  */
443             s->packet = p;
444             ret = USB_RET_ASYNC;
445             break;
446 
447         case USB_MSDM_CSW:
448             if (p->iov.size < 13) {
449                 goto fail;
450             }
451 
452             if (s->req) {
453                 /* still in flight */
454                 DPRINTF("Deferring packet %p [wait status]\n", p);
455                 s->packet = p;
456                 ret = USB_RET_ASYNC;
457             } else {
458                 usb_msd_send_status(s, p);
459                 s->mode = USB_MSDM_CBW;
460                 ret = 13;
461             }
462             break;
463 
464         case USB_MSDM_DATAIN:
465             DPRINTF("Data in %zd/%d, scsi_len %d\n",
466                     p->iov.size, s->data_len, s->scsi_len);
467             if (s->scsi_len) {
468                 usb_msd_copy_data(s, p);
469             }
470             if (le32_to_cpu(s->csw.residue)) {
471                 int len = p->iov.size - p->result;
472                 if (len) {
473                     usb_packet_skip(p, len);
474                     s->data_len -= len;
475                     if (s->data_len == 0) {
476                         s->mode = USB_MSDM_CSW;
477                     }
478                 }
479             }
480             if (p->result < p->iov.size) {
481                 DPRINTF("Deferring packet %p [wait data-in]\n", p);
482                 s->packet = p;
483                 ret = USB_RET_ASYNC;
484             } else {
485                 ret = p->result;
486             }
487             break;
488 
489         default:
490             DPRINTF("Unexpected read (len %zd)\n", p->iov.size);
491             goto fail;
492         }
493         break;
494 
495     default:
496         DPRINTF("Bad token\n");
497     fail:
498         ret = USB_RET_STALL;
499         break;
500     }
501 
502     return ret;
503 }
504 
505 static void usb_msd_password_cb(void *opaque, int err)
506 {
507     MSDState *s = opaque;
508 
509     if (!err)
510         err = usb_device_attach(&s->dev);
511 
512     if (err)
513         qdev_unplug(&s->dev.qdev, NULL);
514 }
515 
516 static void *usb_msd_load_request(QEMUFile *f, SCSIRequest *req)
517 {
518     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
519 
520     /* nothing to load, just store req in our state struct */
521     assert(s->req == NULL);
522     scsi_req_ref(req);
523     s->req = req;
524     return NULL;
525 }
526 
527 static const struct SCSIBusInfo usb_msd_scsi_info = {
528     .tcq = false,
529     .max_target = 0,
530     .max_lun = 0,
531 
532     .transfer_data = usb_msd_transfer_data,
533     .complete = usb_msd_command_complete,
534     .cancel = usb_msd_request_cancelled,
535     .load_request = usb_msd_load_request,
536 };
537 
538 static int usb_msd_initfn(USBDevice *dev)
539 {
540     MSDState *s = DO_UPCAST(MSDState, dev, dev);
541     BlockDriverState *bs = s->conf.bs;
542 
543     if (!bs) {
544         error_report("drive property not set");
545         return -1;
546     }
547 
548     blkconf_serial(&s->conf, &s->serial);
549 
550     /*
551      * Hack alert: this pretends to be a block device, but it's really
552      * a SCSI bus that can serve only a single device, which it
553      * creates automatically.  But first it needs to detach from its
554      * blockdev, or else scsi_bus_legacy_add_drive() dies when it
555      * attaches again.
556      *
557      * The hack is probably a bad idea.
558      */
559     bdrv_detach_dev(bs, &s->dev.qdev);
560     s->conf.bs = NULL;
561 
562     if (s->serial) {
563         usb_desc_set_string(dev, STR_SERIALNUMBER, s->serial);
564     } else {
565         usb_desc_create_serial(dev);
566     }
567 
568     usb_desc_init(dev);
569     scsi_bus_new(&s->bus, &s->dev.qdev, &usb_msd_scsi_info);
570     s->scsi_dev = scsi_bus_legacy_add_drive(&s->bus, bs, 0, !!s->removable,
571                                             s->conf.bootindex);
572     if (!s->scsi_dev) {
573         return -1;
574     }
575     s->bus.qbus.allow_hotplug = 0;
576     usb_msd_handle_reset(dev);
577 
578     if (bdrv_key_required(bs)) {
579         if (cur_mon) {
580             monitor_read_bdrv_key_start(cur_mon, bs, usb_msd_password_cb, s);
581             s->dev.auto_attach = 0;
582         } else {
583             autostart = 0;
584         }
585     }
586 
587     return 0;
588 }
589 
590 static USBDevice *usb_msd_init(USBBus *bus, const char *filename)
591 {
592     static int nr=0;
593     char id[8];
594     QemuOpts *opts;
595     DriveInfo *dinfo;
596     USBDevice *dev;
597     const char *p1;
598     char fmt[32];
599 
600     /* parse -usbdevice disk: syntax into drive opts */
601     snprintf(id, sizeof(id), "usb%d", nr++);
602     opts = qemu_opts_create(qemu_find_opts("drive"), id, 0, NULL);
603 
604     p1 = strchr(filename, ':');
605     if (p1++) {
606         const char *p2;
607 
608         if (strstart(filename, "format=", &p2)) {
609             int len = MIN(p1 - p2, sizeof(fmt));
610             pstrcpy(fmt, len, p2);
611             qemu_opt_set(opts, "format", fmt);
612         } else if (*filename != ':') {
613             printf("unrecognized USB mass-storage option %s\n", filename);
614             return NULL;
615         }
616         filename = p1;
617     }
618     if (!*filename) {
619         printf("block device specification needed\n");
620         return NULL;
621     }
622     qemu_opt_set(opts, "file", filename);
623     qemu_opt_set(opts, "if", "none");
624 
625     /* create host drive */
626     dinfo = drive_init(opts, 0);
627     if (!dinfo) {
628         qemu_opts_del(opts);
629         return NULL;
630     }
631 
632     /* create guest device */
633     dev = usb_create(bus, "usb-storage");
634     if (!dev) {
635         return NULL;
636     }
637     if (qdev_prop_set_drive(&dev->qdev, "drive", dinfo->bdrv) < 0) {
638         qdev_free(&dev->qdev);
639         return NULL;
640     }
641     if (qdev_init(&dev->qdev) < 0)
642         return NULL;
643 
644     return dev;
645 }
646 
647 static const VMStateDescription vmstate_usb_msd = {
648     .name = "usb-storage",
649     .version_id = 1,
650     .minimum_version_id = 1,
651     .fields = (VMStateField []) {
652         VMSTATE_USB_DEVICE(dev, MSDState),
653         VMSTATE_UINT32(mode, MSDState),
654         VMSTATE_UINT32(scsi_len, MSDState),
655         VMSTATE_UINT32(scsi_off, MSDState),
656         VMSTATE_UINT32(data_len, MSDState),
657         VMSTATE_UINT32(csw.sig, MSDState),
658         VMSTATE_UINT32(csw.tag, MSDState),
659         VMSTATE_UINT32(csw.residue, MSDState),
660         VMSTATE_UINT8(csw.status, MSDState),
661         VMSTATE_END_OF_LIST()
662     }
663 };
664 
665 static Property msd_properties[] = {
666     DEFINE_BLOCK_PROPERTIES(MSDState, conf),
667     DEFINE_PROP_STRING("serial", MSDState, serial),
668     DEFINE_PROP_BIT("removable", MSDState, removable, 0, false),
669     DEFINE_PROP_END_OF_LIST(),
670 };
671 
672 static void usb_msd_class_initfn(ObjectClass *klass, void *data)
673 {
674     DeviceClass *dc = DEVICE_CLASS(klass);
675     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
676 
677     uc->init           = usb_msd_initfn;
678     uc->product_desc   = "QEMU USB MSD";
679     uc->usb_desc       = &desc;
680     uc->cancel_packet  = usb_msd_cancel_io;
681     uc->handle_attach  = usb_desc_attach;
682     uc->handle_reset   = usb_msd_handle_reset;
683     uc->handle_control = usb_msd_handle_control;
684     uc->handle_data    = usb_msd_handle_data;
685     dc->fw_name = "storage";
686     dc->vmsd = &vmstate_usb_msd;
687     dc->props = msd_properties;
688 }
689 
690 static TypeInfo msd_info = {
691     .name          = "usb-storage",
692     .parent        = TYPE_USB_DEVICE,
693     .instance_size = sizeof(MSDState),
694     .class_init    = usb_msd_class_initfn,
695 };
696 
697 static void usb_msd_register_types(void)
698 {
699     type_register_static(&msd_info);
700     usb_legacy_register("usb-storage", "disk", usb_msd_init);
701 }
702 
703 type_init(usb_msd_register_types)
704