xref: /openbmc/qemu/hw/usb/dev-storage.c (revision d901eff3)
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 {
251             if (s->data_len) {
252                 int len = (p->iov.size - p->result);
253                 usb_packet_skip(p, len);
254                 s->data_len -= len;
255             }
256             if (s->data_len == 0) {
257                 s->mode = USB_MSDM_CSW;
258             }
259         }
260         usb_msd_packet_complete(s);
261     } else if (s->data_len == 0) {
262         s->mode = USB_MSDM_CSW;
263     }
264     scsi_req_unref(req);
265     s->req = NULL;
266 }
267 
268 static void usb_msd_request_cancelled(SCSIRequest *req)
269 {
270     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
271 
272     if (req == s->req) {
273         scsi_req_unref(s->req);
274         s->req = NULL;
275         s->scsi_len = 0;
276     }
277 }
278 
279 static void usb_msd_handle_reset(USBDevice *dev)
280 {
281     MSDState *s = (MSDState *)dev;
282 
283     DPRINTF("Reset\n");
284     if (s->req) {
285         scsi_req_cancel(s->req);
286     }
287     assert(s->req == NULL);
288 
289     if (s->packet) {
290         s->packet->result = USB_RET_STALL;
291         usb_msd_packet_complete(s);
292     }
293 
294     s->mode = USB_MSDM_CBW;
295 }
296 
297 static int usb_msd_handle_control(USBDevice *dev, USBPacket *p,
298                int request, int value, int index, int length, uint8_t *data)
299 {
300     MSDState *s = (MSDState *)dev;
301     int ret;
302 
303     ret = usb_desc_handle_control(dev, p, request, value, index, length, data);
304     if (ret >= 0) {
305         return ret;
306     }
307 
308     ret = 0;
309     switch (request) {
310     case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
311         ret = 0;
312         break;
313         /* Class specific requests.  */
314     case ClassInterfaceOutRequest | MassStorageReset:
315         /* Reset state ready for the next CBW.  */
316         s->mode = USB_MSDM_CBW;
317         ret = 0;
318         break;
319     case ClassInterfaceRequest | GetMaxLun:
320         data[0] = 0;
321         ret = 1;
322         break;
323     default:
324         ret = USB_RET_STALL;
325         break;
326     }
327     return ret;
328 }
329 
330 static void usb_msd_cancel_io(USBDevice *dev, USBPacket *p)
331 {
332     MSDState *s = DO_UPCAST(MSDState, dev, dev);
333 
334     assert(s->packet == p);
335     s->packet = NULL;
336 
337     if (s->req) {
338         scsi_req_cancel(s->req);
339     }
340 }
341 
342 static int usb_msd_handle_data(USBDevice *dev, USBPacket *p)
343 {
344     MSDState *s = (MSDState *)dev;
345     uint32_t tag;
346     int ret = 0;
347     struct usb_msd_cbw cbw;
348     uint8_t devep = p->ep->nr;
349 
350     switch (p->pid) {
351     case USB_TOKEN_OUT:
352         if (devep != 2)
353             goto fail;
354 
355         switch (s->mode) {
356         case USB_MSDM_CBW:
357             if (p->iov.size != 31) {
358                 fprintf(stderr, "usb-msd: Bad CBW size");
359                 goto fail;
360             }
361             usb_packet_copy(p, &cbw, 31);
362             if (le32_to_cpu(cbw.sig) != 0x43425355) {
363                 fprintf(stderr, "usb-msd: Bad signature %08x\n",
364                         le32_to_cpu(cbw.sig));
365                 goto fail;
366             }
367             DPRINTF("Command on LUN %d\n", cbw.lun);
368             if (cbw.lun != 0) {
369                 fprintf(stderr, "usb-msd: Bad LUN %d\n", cbw.lun);
370                 goto fail;
371             }
372             tag = le32_to_cpu(cbw.tag);
373             s->data_len = le32_to_cpu(cbw.data_len);
374             if (s->data_len == 0) {
375                 s->mode = USB_MSDM_CSW;
376             } else if (cbw.flags & 0x80) {
377                 s->mode = USB_MSDM_DATAIN;
378             } else {
379                 s->mode = USB_MSDM_DATAOUT;
380             }
381             DPRINTF("Command tag 0x%x flags %08x len %d data %d\n",
382                     tag, cbw.flags, cbw.cmd_len, s->data_len);
383             assert(le32_to_cpu(s->csw.residue) == 0);
384             s->scsi_len = 0;
385             s->req = scsi_req_new(s->scsi_dev, tag, 0, cbw.cmd, NULL);
386             scsi_req_enqueue(s->req);
387             if (s->req && s->req->cmd.xfer != SCSI_XFER_NONE) {
388                 scsi_req_continue(s->req);
389             }
390             ret = p->result;
391             break;
392 
393         case USB_MSDM_DATAOUT:
394             DPRINTF("Data out %zd/%d\n", p->iov.size, s->data_len);
395             if (p->iov.size > s->data_len) {
396                 goto fail;
397             }
398 
399             if (s->scsi_len) {
400                 usb_msd_copy_data(s, p);
401             }
402             if (le32_to_cpu(s->csw.residue)) {
403                 int len = p->iov.size - p->result;
404                 if (len) {
405                     usb_packet_skip(p, len);
406                     s->data_len -= len;
407                     if (s->data_len == 0) {
408                         s->mode = USB_MSDM_CSW;
409                     }
410                 }
411             }
412             if (p->result < p->iov.size) {
413                 DPRINTF("Deferring packet %p\n", p);
414                 s->packet = p;
415                 ret = USB_RET_ASYNC;
416             } else {
417                 ret = p->result;
418             }
419             break;
420 
421         default:
422             DPRINTF("Unexpected write (len %zd)\n", p->iov.size);
423             goto fail;
424         }
425         break;
426 
427     case USB_TOKEN_IN:
428         if (devep != 1)
429             goto fail;
430 
431         switch (s->mode) {
432         case USB_MSDM_DATAOUT:
433             if (s->data_len != 0 || p->iov.size < 13) {
434                 goto fail;
435             }
436             /* Waiting for SCSI write to complete.  */
437             s->packet = p;
438             ret = USB_RET_ASYNC;
439             break;
440 
441         case USB_MSDM_CSW:
442             if (p->iov.size < 13) {
443                 goto fail;
444             }
445 
446             if (s->req) {
447                 /* still in flight */
448                 s->packet = p;
449                 ret = USB_RET_ASYNC;
450             } else {
451                 usb_msd_send_status(s, p);
452                 s->mode = USB_MSDM_CBW;
453                 ret = 13;
454             }
455             break;
456 
457         case USB_MSDM_DATAIN:
458             DPRINTF("Data in %zd/%d, scsi_len %d\n",
459                     p->iov.size, s->data_len, s->scsi_len);
460             if (s->scsi_len) {
461                 usb_msd_copy_data(s, p);
462             }
463             if (le32_to_cpu(s->csw.residue)) {
464                 int len = p->iov.size - p->result;
465                 if (len) {
466                     usb_packet_skip(p, len);
467                     s->data_len -= len;
468                     if (s->data_len == 0) {
469                         s->mode = USB_MSDM_CSW;
470                     }
471                 }
472             }
473             if (p->result < p->iov.size) {
474                 DPRINTF("Deferring packet %p\n", p);
475                 s->packet = p;
476                 ret = USB_RET_ASYNC;
477             } else {
478                 ret = p->result;
479             }
480             break;
481 
482         default:
483             DPRINTF("Unexpected read (len %zd)\n", p->iov.size);
484             goto fail;
485         }
486         break;
487 
488     default:
489         DPRINTF("Bad token\n");
490     fail:
491         ret = USB_RET_STALL;
492         break;
493     }
494 
495     return ret;
496 }
497 
498 static void usb_msd_password_cb(void *opaque, int err)
499 {
500     MSDState *s = opaque;
501 
502     if (!err)
503         err = usb_device_attach(&s->dev);
504 
505     if (err)
506         qdev_unplug(&s->dev.qdev, NULL);
507 }
508 
509 static void *usb_msd_load_request(QEMUFile *f, SCSIRequest *req)
510 {
511     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
512 
513     /* nothing to load, just store req in our state struct */
514     assert(s->req == NULL);
515     scsi_req_ref(req);
516     s->req = req;
517     return NULL;
518 }
519 
520 static const struct SCSIBusInfo usb_msd_scsi_info = {
521     .tcq = false,
522     .max_target = 0,
523     .max_lun = 0,
524 
525     .transfer_data = usb_msd_transfer_data,
526     .complete = usb_msd_command_complete,
527     .cancel = usb_msd_request_cancelled,
528     .load_request = usb_msd_load_request,
529 };
530 
531 static int usb_msd_initfn(USBDevice *dev)
532 {
533     MSDState *s = DO_UPCAST(MSDState, dev, dev);
534     BlockDriverState *bs = s->conf.bs;
535 
536     if (!bs) {
537         error_report("drive property not set");
538         return -1;
539     }
540 
541     blkconf_serial(&s->conf, &s->serial);
542 
543     /*
544      * Hack alert: this pretends to be a block device, but it's really
545      * a SCSI bus that can serve only a single device, which it
546      * creates automatically.  But first it needs to detach from its
547      * blockdev, or else scsi_bus_legacy_add_drive() dies when it
548      * attaches again.
549      *
550      * The hack is probably a bad idea.
551      */
552     bdrv_detach_dev(bs, &s->dev.qdev);
553     s->conf.bs = NULL;
554 
555     if (s->serial) {
556         usb_desc_set_string(dev, STR_SERIALNUMBER, s->serial);
557     } else {
558         usb_desc_create_serial(dev);
559     }
560 
561     usb_desc_init(dev);
562     scsi_bus_new(&s->bus, &s->dev.qdev, &usb_msd_scsi_info);
563     s->scsi_dev = scsi_bus_legacy_add_drive(&s->bus, bs, 0, !!s->removable,
564                                             s->conf.bootindex);
565     if (!s->scsi_dev) {
566         return -1;
567     }
568     s->bus.qbus.allow_hotplug = 0;
569     usb_msd_handle_reset(dev);
570 
571     if (bdrv_key_required(bs)) {
572         if (cur_mon) {
573             monitor_read_bdrv_key_start(cur_mon, bs, usb_msd_password_cb, s);
574             s->dev.auto_attach = 0;
575         } else {
576             autostart = 0;
577         }
578     }
579 
580     return 0;
581 }
582 
583 static USBDevice *usb_msd_init(USBBus *bus, const char *filename)
584 {
585     static int nr=0;
586     char id[8];
587     QemuOpts *opts;
588     DriveInfo *dinfo;
589     USBDevice *dev;
590     const char *p1;
591     char fmt[32];
592 
593     /* parse -usbdevice disk: syntax into drive opts */
594     snprintf(id, sizeof(id), "usb%d", nr++);
595     opts = qemu_opts_create(qemu_find_opts("drive"), id, 0, NULL);
596 
597     p1 = strchr(filename, ':');
598     if (p1++) {
599         const char *p2;
600 
601         if (strstart(filename, "format=", &p2)) {
602             int len = MIN(p1 - p2, sizeof(fmt));
603             pstrcpy(fmt, len, p2);
604             qemu_opt_set(opts, "format", fmt);
605         } else if (*filename != ':') {
606             printf("unrecognized USB mass-storage option %s\n", filename);
607             return NULL;
608         }
609         filename = p1;
610     }
611     if (!*filename) {
612         printf("block device specification needed\n");
613         return NULL;
614     }
615     qemu_opt_set(opts, "file", filename);
616     qemu_opt_set(opts, "if", "none");
617 
618     /* create host drive */
619     dinfo = drive_init(opts, 0);
620     if (!dinfo) {
621         qemu_opts_del(opts);
622         return NULL;
623     }
624 
625     /* create guest device */
626     dev = usb_create(bus, "usb-storage");
627     if (!dev) {
628         return NULL;
629     }
630     if (qdev_prop_set_drive(&dev->qdev, "drive", dinfo->bdrv) < 0) {
631         qdev_free(&dev->qdev);
632         return NULL;
633     }
634     if (qdev_init(&dev->qdev) < 0)
635         return NULL;
636 
637     return dev;
638 }
639 
640 static const VMStateDescription vmstate_usb_msd = {
641     .name = "usb-storage",
642     .version_id = 1,
643     .minimum_version_id = 1,
644     .fields = (VMStateField []) {
645         VMSTATE_USB_DEVICE(dev, MSDState),
646         VMSTATE_UINT32(mode, MSDState),
647         VMSTATE_UINT32(scsi_len, MSDState),
648         VMSTATE_UINT32(scsi_off, MSDState),
649         VMSTATE_UINT32(data_len, MSDState),
650         VMSTATE_UINT32(csw.sig, MSDState),
651         VMSTATE_UINT32(csw.tag, MSDState),
652         VMSTATE_UINT32(csw.residue, MSDState),
653         VMSTATE_UINT8(csw.status, MSDState),
654         VMSTATE_END_OF_LIST()
655     }
656 };
657 
658 static Property msd_properties[] = {
659     DEFINE_BLOCK_PROPERTIES(MSDState, conf),
660     DEFINE_PROP_STRING("serial", MSDState, serial),
661     DEFINE_PROP_BIT("removable", MSDState, removable, 0, false),
662     DEFINE_PROP_END_OF_LIST(),
663 };
664 
665 static void usb_msd_class_initfn(ObjectClass *klass, void *data)
666 {
667     DeviceClass *dc = DEVICE_CLASS(klass);
668     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
669 
670     uc->init           = usb_msd_initfn;
671     uc->product_desc   = "QEMU USB MSD";
672     uc->usb_desc       = &desc;
673     uc->cancel_packet  = usb_msd_cancel_io;
674     uc->handle_attach  = usb_desc_attach;
675     uc->handle_reset   = usb_msd_handle_reset;
676     uc->handle_control = usb_msd_handle_control;
677     uc->handle_data    = usb_msd_handle_data;
678     dc->fw_name = "storage";
679     dc->vmsd = &vmstate_usb_msd;
680     dc->props = msd_properties;
681 }
682 
683 static TypeInfo msd_info = {
684     .name          = "usb-storage",
685     .parent        = TYPE_USB_DEVICE,
686     .instance_size = sizeof(MSDState),
687     .class_init    = usb_msd_class_initfn,
688 };
689 
690 static void usb_msd_register_types(void)
691 {
692     type_register_static(&msd_info);
693     usb_legacy_register("usb-storage", "disk", usb_msd_init);
694 }
695 
696 type_init(usb_msd_register_types)
697