xref: /openbmc/qemu/hw/scsi/spapr_vscsi.c (revision 2993683b)
1 /*
2  * QEMU PowerPC pSeries Logical Partition (aka sPAPR) hardware System Emulator
3  *
4  * PAPR Virtual SCSI, aka ibmvscsi
5  *
6  * Copyright (c) 2010,2011 Benjamin Herrenschmidt, IBM Corporation.
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a copy
9  * of this software and associated documentation files (the "Software"), to deal
10  * in the Software without restriction, including without limitation the rights
11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12  * copies of the Software, and to permit persons to whom the Software is
13  * furnished to do so, subject to the following conditions:
14  *
15  * The above copyright notice and this permission notice shall be included in
16  * all copies or substantial portions of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24  * THE SOFTWARE.
25  *
26  * TODO:
27  *
28  *  - Cleanups :-)
29  *  - Sort out better how to assign devices to VSCSI instances
30  *  - Fix residual counts
31  *  - Add indirect descriptors support
32  *  - Maybe do autosense (PAPR seems to mandate it, linux doesn't care)
33  */
34 #include "hw/hw.h"
35 #include "hw/scsi/scsi.h"
36 #include "block/scsi.h"
37 #include "srp.h"
38 #include "hw/qdev.h"
39 #include "hw/ppc/spapr.h"
40 #include "hw/ppc/spapr_vio.h"
41 #include "viosrp.h"
42 
43 #include <libfdt.h>
44 
45 /*#define DEBUG_VSCSI*/
46 
47 #ifdef DEBUG_VSCSI
48 #define dprintf(fmt, ...) \
49     do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
50 #else
51 #define dprintf(fmt, ...) \
52     do { } while (0)
53 #endif
54 
55 /*
56  * Virtual SCSI device
57  */
58 
59 /* Random numbers */
60 #define VSCSI_MAX_SECTORS       4096
61 #define VSCSI_REQ_LIMIT         24
62 
63 #define SCSI_SENSE_BUF_SIZE     96
64 #define SRP_RSP_SENSE_DATA_LEN  18
65 
66 typedef union vscsi_crq {
67     struct viosrp_crq s;
68     uint8_t raw[16];
69 } vscsi_crq;
70 
71 typedef struct vscsi_req {
72     vscsi_crq               crq;
73     union viosrp_iu         iu;
74 
75     /* SCSI request tracking */
76     SCSIRequest             *sreq;
77     uint32_t                qtag; /* qemu tag != srp tag */
78     int                     lun;
79     int                     active;
80     long                    data_len;
81     int                     writing;
82     int                     senselen;
83     uint8_t                 sense[SCSI_SENSE_BUF_SIZE];
84 
85     /* RDMA related bits */
86     uint8_t                 dma_fmt;
87     struct srp_direct_buf   ext_desc;
88     struct srp_direct_buf   *cur_desc;
89     struct srp_indirect_buf *ind_desc;
90     int                     local_desc;
91     int                     total_desc;
92 } vscsi_req;
93 
94 #define TYPE_VIO_SPAPR_VSCSI_DEVICE "spapr-vscsi"
95 #define VIO_SPAPR_VSCSI_DEVICE(obj) \
96      OBJECT_CHECK(VSCSIState, (obj), TYPE_VIO_SPAPR_VSCSI_DEVICE)
97 
98 typedef struct {
99     VIOsPAPRDevice vdev;
100     SCSIBus bus;
101     vscsi_req reqs[VSCSI_REQ_LIMIT];
102 } VSCSIState;
103 
104 static struct vscsi_req *vscsi_get_req(VSCSIState *s)
105 {
106     vscsi_req *req;
107     int i;
108 
109     for (i = 0; i < VSCSI_REQ_LIMIT; i++) {
110         req = &s->reqs[i];
111         if (!req->active) {
112             memset(req, 0, sizeof(*req));
113             req->qtag = i;
114             req->active = 1;
115             return req;
116         }
117     }
118     return NULL;
119 }
120 
121 static void vscsi_put_req(vscsi_req *req)
122 {
123     if (req->sreq != NULL) {
124         scsi_req_unref(req->sreq);
125     }
126     req->sreq = NULL;
127     req->active = 0;
128 }
129 
130 static SCSIDevice *vscsi_device_find(SCSIBus *bus, uint64_t srp_lun, int *lun)
131 {
132     int channel = 0, id = 0;
133 
134 retry:
135     switch (srp_lun >> 62) {
136     case 0:
137         if ((srp_lun >> 56) != 0) {
138             channel = (srp_lun >> 56) & 0x3f;
139             id = (srp_lun >> 48) & 0xff;
140             srp_lun <<= 16;
141             goto retry;
142         }
143         *lun = (srp_lun >> 48) & 0xff;
144         break;
145 
146     case 1:
147         *lun = (srp_lun >> 48) & 0x3fff;
148         break;
149     case 2:
150         channel = (srp_lun >> 53) & 0x7;
151         id = (srp_lun >> 56) & 0x3f;
152         *lun = (srp_lun >> 48) & 0x1f;
153         break;
154     case 3:
155         *lun = -1;
156         return NULL;
157     default:
158         abort();
159     }
160 
161     return scsi_device_find(bus, channel, id, *lun);
162 }
163 
164 static int vscsi_send_iu(VSCSIState *s, vscsi_req *req,
165                          uint64_t length, uint8_t format)
166 {
167     long rc, rc1;
168 
169     /* First copy the SRP */
170     rc = spapr_vio_dma_write(&s->vdev, req->crq.s.IU_data_ptr,
171                              &req->iu, length);
172     if (rc) {
173         fprintf(stderr, "vscsi_send_iu: DMA write failure !\n");
174     }
175 
176     req->crq.s.valid = 0x80;
177     req->crq.s.format = format;
178     req->crq.s.reserved = 0x00;
179     req->crq.s.timeout = cpu_to_be16(0x0000);
180     req->crq.s.IU_length = cpu_to_be16(length);
181     req->crq.s.IU_data_ptr = req->iu.srp.rsp.tag; /* right byte order */
182 
183     if (rc == 0) {
184         req->crq.s.status = 0x99; /* Just needs to be non-zero */
185     } else {
186         req->crq.s.status = 0x00;
187     }
188 
189     rc1 = spapr_vio_send_crq(&s->vdev, req->crq.raw);
190     if (rc1) {
191         fprintf(stderr, "vscsi_send_iu: Error sending response\n");
192         return rc1;
193     }
194 
195     return rc;
196 }
197 
198 static void vscsi_makeup_sense(VSCSIState *s, vscsi_req *req,
199                                uint8_t key, uint8_t asc, uint8_t ascq)
200 {
201     req->senselen = SRP_RSP_SENSE_DATA_LEN;
202 
203     /* Valid bit and 'current errors' */
204     req->sense[0] = (0x1 << 7 | 0x70);
205     /* Sense key */
206     req->sense[2] = key;
207     /* Additional sense length */
208     req->sense[7] = 0xa; /* 10 bytes */
209     /* Additional sense code */
210     req->sense[12] = asc;
211     req->sense[13] = ascq;
212 }
213 
214 static int vscsi_send_rsp(VSCSIState *s, vscsi_req *req,
215                           uint8_t status, int32_t res_in, int32_t res_out)
216 {
217     union viosrp_iu *iu = &req->iu;
218     uint64_t tag = iu->srp.rsp.tag;
219     int total_len = sizeof(iu->srp.rsp);
220 
221     dprintf("VSCSI: Sending resp status: 0x%x, "
222             "res_in: %d, res_out: %d\n", status, res_in, res_out);
223 
224     memset(iu, 0, sizeof(struct srp_rsp));
225     iu->srp.rsp.opcode = SRP_RSP;
226     iu->srp.rsp.req_lim_delta = cpu_to_be32(1);
227     iu->srp.rsp.tag = tag;
228 
229     /* Handle residuals */
230     if (res_in < 0) {
231         iu->srp.rsp.flags |= SRP_RSP_FLAG_DIUNDER;
232         res_in = -res_in;
233     } else if (res_in) {
234         iu->srp.rsp.flags |= SRP_RSP_FLAG_DIOVER;
235     }
236     if (res_out < 0) {
237         iu->srp.rsp.flags |= SRP_RSP_FLAG_DOUNDER;
238         res_out = -res_out;
239     } else if (res_out) {
240         iu->srp.rsp.flags |= SRP_RSP_FLAG_DOOVER;
241     }
242     iu->srp.rsp.data_in_res_cnt = cpu_to_be32(res_in);
243     iu->srp.rsp.data_out_res_cnt = cpu_to_be32(res_out);
244 
245     /* We don't do response data */
246     /* iu->srp.rsp.flags &= ~SRP_RSP_FLAG_RSPVALID; */
247     iu->srp.rsp.resp_data_len = cpu_to_be32(0);
248 
249     /* Handle success vs. failure */
250     iu->srp.rsp.status = status;
251     if (status) {
252         iu->srp.rsp.sol_not = (iu->srp.cmd.sol_not & 0x04) >> 2;
253         if (req->senselen) {
254             req->iu.srp.rsp.flags |= SRP_RSP_FLAG_SNSVALID;
255             req->iu.srp.rsp.sense_data_len = cpu_to_be32(req->senselen);
256             memcpy(req->iu.srp.rsp.data, req->sense, req->senselen);
257             total_len += req->senselen;
258         }
259     } else {
260         iu->srp.rsp.sol_not = (iu->srp.cmd.sol_not & 0x02) >> 1;
261     }
262 
263     vscsi_send_iu(s, req, total_len, VIOSRP_SRP_FORMAT);
264     return 0;
265 }
266 
267 static inline void vscsi_swap_desc(struct srp_direct_buf *desc)
268 {
269     desc->va = be64_to_cpu(desc->va);
270     desc->len = be32_to_cpu(desc->len);
271 }
272 
273 static int vscsi_srp_direct_data(VSCSIState *s, vscsi_req *req,
274                                  uint8_t *buf, uint32_t len)
275 {
276     struct srp_direct_buf *md = req->cur_desc;
277     uint32_t llen;
278     int rc = 0;
279 
280     dprintf("VSCSI: direct segment 0x%x bytes, va=0x%llx desc len=0x%x\n",
281             len, (unsigned long long)md->va, md->len);
282 
283     llen = MIN(len, md->len);
284     if (llen) {
285         if (req->writing) { /* writing = to device = reading from memory */
286             rc = spapr_vio_dma_read(&s->vdev, md->va, buf, llen);
287         } else {
288             rc = spapr_vio_dma_write(&s->vdev, md->va, buf, llen);
289         }
290     }
291     md->len -= llen;
292     md->va += llen;
293 
294     if (rc) {
295         return -1;
296     }
297     return llen;
298 }
299 
300 static int vscsi_srp_indirect_data(VSCSIState *s, vscsi_req *req,
301                                    uint8_t *buf, uint32_t len)
302 {
303     struct srp_direct_buf *td = &req->ind_desc->table_desc;
304     struct srp_direct_buf *md = req->cur_desc;
305     int rc = 0;
306     uint32_t llen, total = 0;
307 
308     dprintf("VSCSI: indirect segment 0x%x bytes, td va=0x%llx len=0x%x\n",
309             len, (unsigned long long)td->va, td->len);
310 
311     /* While we have data ... */
312     while (len) {
313         /* If we have a descriptor but it's empty, go fetch a new one */
314         if (md && md->len == 0) {
315             /* More local available, use one */
316             if (req->local_desc) {
317                 md = ++req->cur_desc;
318                 --req->local_desc;
319                 --req->total_desc;
320                 td->va += sizeof(struct srp_direct_buf);
321             } else {
322                 md = req->cur_desc = NULL;
323             }
324         }
325         /* No descriptor at hand, fetch one */
326         if (!md) {
327             if (!req->total_desc) {
328                 dprintf("VSCSI:   Out of descriptors !\n");
329                 break;
330             }
331             md = req->cur_desc = &req->ext_desc;
332             dprintf("VSCSI:   Reading desc from 0x%llx\n",
333                     (unsigned long long)td->va);
334             rc = spapr_vio_dma_read(&s->vdev, td->va, md,
335                                     sizeof(struct srp_direct_buf));
336             if (rc) {
337                 dprintf("VSCSI: spapr_vio_dma_read -> %d reading ext_desc\n",
338                         rc);
339                 break;
340             }
341             vscsi_swap_desc(md);
342             td->va += sizeof(struct srp_direct_buf);
343             --req->total_desc;
344         }
345         dprintf("VSCSI:   [desc va=0x%llx,len=0x%x] remaining=0x%x\n",
346                 (unsigned long long)md->va, md->len, len);
347 
348         /* Perform transfer */
349         llen = MIN(len, md->len);
350         if (req->writing) { /* writing = to device = reading from memory */
351             rc = spapr_vio_dma_read(&s->vdev, md->va, buf, llen);
352         } else {
353             rc = spapr_vio_dma_write(&s->vdev, md->va, buf, llen);
354         }
355         if (rc) {
356             dprintf("VSCSI: spapr_vio_dma_r/w(%d) -> %d\n", req->writing, rc);
357             break;
358         }
359         dprintf("VSCSI:     data: %02x %02x %02x %02x...\n",
360                 buf[0], buf[1], buf[2], buf[3]);
361 
362         len -= llen;
363         buf += llen;
364         total += llen;
365         md->va += llen;
366         md->len -= llen;
367     }
368     return rc ? -1 : total;
369 }
370 
371 static int vscsi_srp_transfer_data(VSCSIState *s, vscsi_req *req,
372                                    int writing, uint8_t *buf, uint32_t len)
373 {
374     int err = 0;
375 
376     switch (req->dma_fmt) {
377     case SRP_NO_DATA_DESC:
378         dprintf("VSCSI: no data desc transfer, skipping 0x%x bytes\n", len);
379         break;
380     case SRP_DATA_DESC_DIRECT:
381         err = vscsi_srp_direct_data(s, req, buf, len);
382         break;
383     case SRP_DATA_DESC_INDIRECT:
384         err = vscsi_srp_indirect_data(s, req, buf, len);
385         break;
386     }
387     return err;
388 }
389 
390 /* Bits from linux srp */
391 static int data_out_desc_size(struct srp_cmd *cmd)
392 {
393     int size = 0;
394     uint8_t fmt = cmd->buf_fmt >> 4;
395 
396     switch (fmt) {
397     case SRP_NO_DATA_DESC:
398         break;
399     case SRP_DATA_DESC_DIRECT:
400         size = sizeof(struct srp_direct_buf);
401         break;
402     case SRP_DATA_DESC_INDIRECT:
403         size = sizeof(struct srp_indirect_buf) +
404             sizeof(struct srp_direct_buf)*cmd->data_out_desc_cnt;
405         break;
406     default:
407         break;
408     }
409     return size;
410 }
411 
412 static int vscsi_preprocess_desc(vscsi_req *req)
413 {
414     struct srp_cmd *cmd = &req->iu.srp.cmd;
415     int offset, i;
416 
417     offset = cmd->add_cdb_len & ~3;
418 
419     if (req->writing) {
420         req->dma_fmt = cmd->buf_fmt >> 4;
421     } else {
422         offset += data_out_desc_size(cmd);
423         req->dma_fmt = cmd->buf_fmt & ((1U << 4) - 1);
424     }
425 
426     switch (req->dma_fmt) {
427     case SRP_NO_DATA_DESC:
428         break;
429     case SRP_DATA_DESC_DIRECT:
430         req->cur_desc = (struct srp_direct_buf *)(cmd->add_data + offset);
431         req->total_desc = req->local_desc = 1;
432         vscsi_swap_desc(req->cur_desc);
433         dprintf("VSCSI: using direct RDMA %s, 0x%x bytes MD: 0x%llx\n",
434                 req->writing ? "write" : "read",
435                 req->cur_desc->len, (unsigned long long)req->cur_desc->va);
436         break;
437     case SRP_DATA_DESC_INDIRECT:
438         req->ind_desc = (struct srp_indirect_buf *)(cmd->add_data + offset);
439         vscsi_swap_desc(&req->ind_desc->table_desc);
440         req->total_desc = req->ind_desc->table_desc.len /
441             sizeof(struct srp_direct_buf);
442         req->local_desc = req->writing ? cmd->data_out_desc_cnt :
443             cmd->data_in_desc_cnt;
444         for (i = 0; i < req->local_desc; i++) {
445             vscsi_swap_desc(&req->ind_desc->desc_list[i]);
446         }
447         req->cur_desc = req->local_desc ? &req->ind_desc->desc_list[0] : NULL;
448         dprintf("VSCSI: using indirect RDMA %s, 0x%x bytes %d descs "
449                 "(%d local) VA: 0x%llx\n",
450                 req->writing ? "read" : "write",
451                 be32_to_cpu(req->ind_desc->len),
452                 req->total_desc, req->local_desc,
453                 (unsigned long long)req->ind_desc->table_desc.va);
454         break;
455     default:
456         fprintf(stderr,
457                 "vscsi_preprocess_desc: Unknown format %x\n", req->dma_fmt);
458         return -1;
459     }
460 
461     return 0;
462 }
463 
464 /* Callback to indicate that the SCSI layer has completed a transfer.  */
465 static void vscsi_transfer_data(SCSIRequest *sreq, uint32_t len)
466 {
467     VSCSIState *s = VIO_SPAPR_VSCSI_DEVICE(sreq->bus->qbus.parent);
468     vscsi_req *req = sreq->hba_private;
469     uint8_t *buf;
470     int rc = 0;
471 
472     dprintf("VSCSI: SCSI xfer complete tag=0x%x len=0x%x, req=%p\n",
473             sreq->tag, len, req);
474     if (req == NULL) {
475         fprintf(stderr, "VSCSI: Can't find request for tag 0x%x\n", sreq->tag);
476         return;
477     }
478 
479     if (len) {
480         buf = scsi_req_get_buf(sreq);
481         rc = vscsi_srp_transfer_data(s, req, req->writing, buf, len);
482     }
483     if (rc < 0) {
484         fprintf(stderr, "VSCSI: RDMA error rc=%d!\n", rc);
485         vscsi_makeup_sense(s, req, HARDWARE_ERROR, 0, 0);
486         scsi_req_abort(req->sreq, CHECK_CONDITION);
487         return;
488     }
489 
490     /* Start next chunk */
491     req->data_len -= rc;
492     scsi_req_continue(sreq);
493 }
494 
495 /* Callback to indicate that the SCSI layer has completed a transfer.  */
496 static void vscsi_command_complete(SCSIRequest *sreq, uint32_t status, size_t resid)
497 {
498     VSCSIState *s = VIO_SPAPR_VSCSI_DEVICE(sreq->bus->qbus.parent);
499     vscsi_req *req = sreq->hba_private;
500     int32_t res_in = 0, res_out = 0;
501 
502     dprintf("VSCSI: SCSI cmd complete, r=0x%x tag=0x%x status=0x%x, req=%p\n",
503             reason, sreq->tag, status, req);
504     if (req == NULL) {
505         fprintf(stderr, "VSCSI: Can't find request for tag 0x%x\n", sreq->tag);
506         return;
507     }
508 
509     if (status == CHECK_CONDITION) {
510         req->senselen = scsi_req_get_sense(req->sreq, req->sense,
511                                            sizeof(req->sense));
512         dprintf("VSCSI: Sense data, %d bytes:\n", len);
513         dprintf("       %02x  %02x  %02x  %02x  %02x  %02x  %02x  %02x\n",
514                 req->sense[0], req->sense[1], req->sense[2], req->sense[3],
515                 req->sense[4], req->sense[5], req->sense[6], req->sense[7]);
516         dprintf("       %02x  %02x  %02x  %02x  %02x  %02x  %02x  %02x\n",
517                 req->sense[8], req->sense[9], req->sense[10], req->sense[11],
518                 req->sense[12], req->sense[13], req->sense[14], req->sense[15]);
519     }
520 
521     dprintf("VSCSI: Command complete err=%d\n", status);
522     if (status == 0) {
523         /* We handle overflows, not underflows for normal commands,
524          * but hopefully nobody cares
525          */
526         if (req->writing) {
527             res_out = req->data_len;
528         } else {
529             res_in = req->data_len;
530         }
531     }
532     vscsi_send_rsp(s, req, status, res_in, res_out);
533     vscsi_put_req(req);
534 }
535 
536 static void vscsi_request_cancelled(SCSIRequest *sreq)
537 {
538     vscsi_req *req = sreq->hba_private;
539 
540     vscsi_put_req(req);
541 }
542 
543 static void vscsi_process_login(VSCSIState *s, vscsi_req *req)
544 {
545     union viosrp_iu *iu = &req->iu;
546     struct srp_login_rsp *rsp = &iu->srp.login_rsp;
547     uint64_t tag = iu->srp.rsp.tag;
548 
549     dprintf("VSCSI: Got login, sendin response !\n");
550 
551     /* TODO handle case that requested size is wrong and
552      * buffer format is wrong
553      */
554     memset(iu, 0, sizeof(struct srp_login_rsp));
555     rsp->opcode = SRP_LOGIN_RSP;
556     /* Don't advertise quite as many request as we support to
557      * keep room for management stuff etc...
558      */
559     rsp->req_lim_delta = cpu_to_be32(VSCSI_REQ_LIMIT-2);
560     rsp->tag = tag;
561     rsp->max_it_iu_len = cpu_to_be32(sizeof(union srp_iu));
562     rsp->max_ti_iu_len = cpu_to_be32(sizeof(union srp_iu));
563     /* direct and indirect */
564     rsp->buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT);
565 
566     vscsi_send_iu(s, req, sizeof(*rsp), VIOSRP_SRP_FORMAT);
567 }
568 
569 static void vscsi_inquiry_no_target(VSCSIState *s, vscsi_req *req)
570 {
571     uint8_t *cdb = req->iu.srp.cmd.cdb;
572     uint8_t resp_data[36];
573     int rc, len, alen;
574 
575     /* We dont do EVPD. Also check that page_code is 0 */
576     if ((cdb[1] & 0x01) || (cdb[1] & 0x01) || cdb[2] != 0) {
577         /* Send INVALID FIELD IN CDB */
578         vscsi_makeup_sense(s, req, ILLEGAL_REQUEST, 0x24, 0);
579         vscsi_send_rsp(s, req, CHECK_CONDITION, 0, 0);
580         return;
581     }
582     alen = cdb[3];
583     alen = (alen << 8) | cdb[4];
584     len = MIN(alen, 36);
585 
586     /* Fake up inquiry using PQ=3 */
587     memset(resp_data, 0, 36);
588     resp_data[0] = 0x7f;   /* Not capable of supporting a device here */
589     resp_data[2] = 0x06;   /* SPS-4 */
590     resp_data[3] = 0x02;   /* Resp data format */
591     resp_data[4] = 36 - 5; /* Additional length */
592     resp_data[7] = 0x10;   /* Sync transfers */
593     memcpy(&resp_data[16], "QEMU EMPTY      ", 16);
594     memcpy(&resp_data[8], "QEMU    ", 8);
595 
596     req->writing = 0;
597     vscsi_preprocess_desc(req);
598     rc = vscsi_srp_transfer_data(s, req, 0, resp_data, len);
599     if (rc < 0) {
600         vscsi_makeup_sense(s, req, HARDWARE_ERROR, 0, 0);
601         vscsi_send_rsp(s, req, CHECK_CONDITION, 0, 0);
602     } else {
603         vscsi_send_rsp(s, req, 0, 36 - rc, 0);
604     }
605 }
606 
607 static int vscsi_queue_cmd(VSCSIState *s, vscsi_req *req)
608 {
609     union srp_iu *srp = &req->iu.srp;
610     SCSIDevice *sdev;
611     int n, lun;
612 
613     sdev = vscsi_device_find(&s->bus, be64_to_cpu(srp->cmd.lun), &lun);
614     if (!sdev) {
615         dprintf("VSCSI: Command for lun %08" PRIx64 " with no drive\n", be64_to_cpu(srp->cmd.lun));
616         if (srp->cmd.cdb[0] == INQUIRY) {
617             vscsi_inquiry_no_target(s, req);
618         } else {
619             vscsi_makeup_sense(s, req, ILLEGAL_REQUEST, 0x24, 0x00);
620             vscsi_send_rsp(s, req, CHECK_CONDITION, 0, 0);
621         } return 1;
622     }
623 
624     req->lun = lun;
625     req->sreq = scsi_req_new(sdev, req->qtag, lun, srp->cmd.cdb, req);
626     n = scsi_req_enqueue(req->sreq);
627 
628     dprintf("VSCSI: Queued command tag 0x%x CMD 0x%x ID %d LUN %d ret: %d\n",
629             req->qtag, srp->cmd.cdb[0], id, lun, n);
630 
631     if (n) {
632         /* Transfer direction must be set before preprocessing the
633          * descriptors
634          */
635         req->writing = (n < 1);
636 
637         /* Preprocess RDMA descriptors */
638         vscsi_preprocess_desc(req);
639 
640         /* Get transfer direction and initiate transfer */
641         if (n > 0) {
642             req->data_len = n;
643         } else if (n < 0) {
644             req->data_len = -n;
645         }
646         scsi_req_continue(req->sreq);
647     }
648     /* Don't touch req here, it may have been recycled already */
649 
650     return 0;
651 }
652 
653 static int vscsi_process_tsk_mgmt(VSCSIState *s, vscsi_req *req)
654 {
655     union viosrp_iu *iu = &req->iu;
656     int fn;
657 
658     fprintf(stderr, "vscsi_process_tsk_mgmt %02x\n",
659             iu->srp.tsk_mgmt.tsk_mgmt_func);
660 
661     switch (iu->srp.tsk_mgmt.tsk_mgmt_func) {
662 #if 0 /* We really don't deal with these for now */
663     case SRP_TSK_ABORT_TASK:
664         fn = ABORT_TASK;
665         break;
666     case SRP_TSK_ABORT_TASK_SET:
667         fn = ABORT_TASK_SET;
668         break;
669     case SRP_TSK_CLEAR_TASK_SET:
670         fn = CLEAR_TASK_SET;
671         break;
672     case SRP_TSK_LUN_RESET:
673         fn = LOGICAL_UNIT_RESET;
674         break;
675     case SRP_TSK_CLEAR_ACA:
676         fn = CLEAR_ACA;
677         break;
678 #endif
679     default:
680         fn = 0;
681     }
682     if (fn) {
683         /* XXX Send/Handle target task management */
684         ;
685     } else {
686         vscsi_makeup_sense(s, req, ILLEGAL_REQUEST, 0x20, 0);
687         vscsi_send_rsp(s, req, CHECK_CONDITION, 0, 0);
688     }
689     return !fn;
690 }
691 
692 static int vscsi_handle_srp_req(VSCSIState *s, vscsi_req *req)
693 {
694     union srp_iu *srp = &req->iu.srp;
695     int done = 1;
696     uint8_t opcode = srp->rsp.opcode;
697 
698     switch (opcode) {
699     case SRP_LOGIN_REQ:
700         vscsi_process_login(s, req);
701         break;
702     case SRP_TSK_MGMT:
703         done = vscsi_process_tsk_mgmt(s, req);
704         break;
705     case SRP_CMD:
706         done = vscsi_queue_cmd(s, req);
707         break;
708     case SRP_LOGIN_RSP:
709     case SRP_I_LOGOUT:
710     case SRP_T_LOGOUT:
711     case SRP_RSP:
712     case SRP_CRED_REQ:
713     case SRP_CRED_RSP:
714     case SRP_AER_REQ:
715     case SRP_AER_RSP:
716         fprintf(stderr, "VSCSI: Unsupported opcode %02x\n", opcode);
717         break;
718     default:
719         fprintf(stderr, "VSCSI: Unknown type %02x\n", opcode);
720     }
721 
722     return done;
723 }
724 
725 static int vscsi_send_adapter_info(VSCSIState *s, vscsi_req *req)
726 {
727     struct viosrp_adapter_info *sinfo;
728     struct mad_adapter_info_data info;
729     int rc;
730 
731     sinfo = &req->iu.mad.adapter_info;
732 
733 #if 0 /* What for ? */
734     rc = spapr_vio_dma_read(&s->vdev, be64_to_cpu(sinfo->buffer),
735                             &info, be16_to_cpu(sinfo->common.length));
736     if (rc) {
737         fprintf(stderr, "vscsi_send_adapter_info: DMA read failure !\n");
738     }
739 #endif
740     memset(&info, 0, sizeof(info));
741     strcpy(info.srp_version, SRP_VERSION);
742     memcpy(info.partition_name, "qemu", sizeof("qemu"));
743     info.partition_number = cpu_to_be32(0);
744     info.mad_version = cpu_to_be32(1);
745     info.os_type = cpu_to_be32(2);
746     info.port_max_txu[0] = cpu_to_be32(VSCSI_MAX_SECTORS << 9);
747 
748     rc = spapr_vio_dma_write(&s->vdev, be64_to_cpu(sinfo->buffer),
749                              &info, be16_to_cpu(sinfo->common.length));
750     if (rc)  {
751         fprintf(stderr, "vscsi_send_adapter_info: DMA write failure !\n");
752     }
753 
754     sinfo->common.status = rc ? cpu_to_be32(1) : 0;
755 
756     return vscsi_send_iu(s, req, sizeof(*sinfo), VIOSRP_MAD_FORMAT);
757 }
758 
759 static int vscsi_handle_mad_req(VSCSIState *s, vscsi_req *req)
760 {
761     union mad_iu *mad = &req->iu.mad;
762 
763     switch (be32_to_cpu(mad->empty_iu.common.type)) {
764     case VIOSRP_EMPTY_IU_TYPE:
765         fprintf(stderr, "Unsupported EMPTY MAD IU\n");
766         break;
767     case VIOSRP_ERROR_LOG_TYPE:
768         fprintf(stderr, "Unsupported ERROR LOG MAD IU\n");
769         mad->error_log.common.status = cpu_to_be16(1);
770         vscsi_send_iu(s, req, sizeof(mad->error_log), VIOSRP_MAD_FORMAT);
771         break;
772     case VIOSRP_ADAPTER_INFO_TYPE:
773         vscsi_send_adapter_info(s, req);
774         break;
775     case VIOSRP_HOST_CONFIG_TYPE:
776         mad->host_config.common.status = cpu_to_be16(1);
777         vscsi_send_iu(s, req, sizeof(mad->host_config), VIOSRP_MAD_FORMAT);
778         break;
779     default:
780         fprintf(stderr, "VSCSI: Unknown MAD type %02x\n",
781                 be32_to_cpu(mad->empty_iu.common.type));
782     }
783 
784     return 1;
785 }
786 
787 static void vscsi_got_payload(VSCSIState *s, vscsi_crq *crq)
788 {
789     vscsi_req *req;
790     int done;
791 
792     req = vscsi_get_req(s);
793     if (req == NULL) {
794         fprintf(stderr, "VSCSI: Failed to get a request !\n");
795         return;
796     }
797 
798     /* We only support a limited number of descriptors, we know
799      * the ibmvscsi driver uses up to 10 max, so it should fit
800      * in our 256 bytes IUs. If not we'll have to increase the size
801      * of the structure.
802      */
803     if (crq->s.IU_length > sizeof(union viosrp_iu)) {
804         fprintf(stderr, "VSCSI: SRP IU too long (%d bytes) !\n",
805                 crq->s.IU_length);
806         vscsi_put_req(req);
807         return;
808     }
809 
810     /* XXX Handle failure differently ? */
811     if (spapr_vio_dma_read(&s->vdev, crq->s.IU_data_ptr, &req->iu,
812                            crq->s.IU_length)) {
813         fprintf(stderr, "vscsi_got_payload: DMA read failure !\n");
814         vscsi_put_req(req);
815         return;
816     }
817     memcpy(&req->crq, crq, sizeof(vscsi_crq));
818 
819     if (crq->s.format == VIOSRP_MAD_FORMAT) {
820         done = vscsi_handle_mad_req(s, req);
821     } else {
822         done = vscsi_handle_srp_req(s, req);
823     }
824 
825     if (done) {
826         vscsi_put_req(req);
827     }
828 }
829 
830 
831 static int vscsi_do_crq(struct VIOsPAPRDevice *dev, uint8_t *crq_data)
832 {
833     VSCSIState *s = VIO_SPAPR_VSCSI_DEVICE(dev);
834     vscsi_crq crq;
835 
836     memcpy(crq.raw, crq_data, 16);
837     crq.s.timeout = be16_to_cpu(crq.s.timeout);
838     crq.s.IU_length = be16_to_cpu(crq.s.IU_length);
839     crq.s.IU_data_ptr = be64_to_cpu(crq.s.IU_data_ptr);
840 
841     dprintf("VSCSI: do_crq %02x %02x ...\n", crq.raw[0], crq.raw[1]);
842 
843     switch (crq.s.valid) {
844     case 0xc0: /* Init command/response */
845 
846         /* Respond to initialization request */
847         if (crq.s.format == 0x01) {
848             memset(crq.raw, 0, 16);
849             crq.s.valid = 0xc0;
850             crq.s.format = 0x02;
851             spapr_vio_send_crq(dev, crq.raw);
852         }
853 
854         /* Note that in hotplug cases, we might get a 0x02
855          * as a result of us emitting the init request
856          */
857 
858         break;
859     case 0xff: /* Link event */
860 
861         /* Not handled for now */
862 
863         break;
864     case 0x80: /* Payloads */
865         switch (crq.s.format) {
866         case VIOSRP_SRP_FORMAT: /* AKA VSCSI request */
867         case VIOSRP_MAD_FORMAT: /* AKA VSCSI response */
868             vscsi_got_payload(s, &crq);
869             break;
870         case VIOSRP_OS400_FORMAT:
871         case VIOSRP_AIX_FORMAT:
872         case VIOSRP_LINUX_FORMAT:
873         case VIOSRP_INLINE_FORMAT:
874             fprintf(stderr, "vscsi_do_srq: Unsupported payload format %02x\n",
875                     crq.s.format);
876             break;
877         default:
878             fprintf(stderr, "vscsi_do_srq: Unknown payload format %02x\n",
879                     crq.s.format);
880         }
881         break;
882     default:
883         fprintf(stderr, "vscsi_do_crq: unknown CRQ %02x %02x ...\n",
884                 crq.raw[0], crq.raw[1]);
885     };
886 
887     return 0;
888 }
889 
890 static const struct SCSIBusInfo vscsi_scsi_info = {
891     .tcq = true,
892     .max_channel = 7, /* logical unit addressing format */
893     .max_target = 63,
894     .max_lun = 31,
895 
896     .transfer_data = vscsi_transfer_data,
897     .complete = vscsi_command_complete,
898     .cancel = vscsi_request_cancelled
899 };
900 
901 static void spapr_vscsi_reset(VIOsPAPRDevice *dev)
902 {
903     VSCSIState *s = VIO_SPAPR_VSCSI_DEVICE(dev);
904     int i;
905 
906     memset(s->reqs, 0, sizeof(s->reqs));
907     for (i = 0; i < VSCSI_REQ_LIMIT; i++) {
908         s->reqs[i].qtag = i;
909     }
910 }
911 
912 static int spapr_vscsi_init(VIOsPAPRDevice *dev)
913 {
914     VSCSIState *s = VIO_SPAPR_VSCSI_DEVICE(dev);
915 
916     dev->crq.SendFunc = vscsi_do_crq;
917 
918     scsi_bus_new(&s->bus, &dev->qdev, &vscsi_scsi_info);
919     if (!dev->qdev.hotplugged) {
920         scsi_bus_legacy_handle_cmdline(&s->bus);
921     }
922 
923     return 0;
924 }
925 
926 void spapr_vscsi_create(VIOsPAPRBus *bus)
927 {
928     DeviceState *dev;
929 
930     dev = qdev_create(&bus->bus, "spapr-vscsi");
931 
932     qdev_init_nofail(dev);
933 }
934 
935 static int spapr_vscsi_devnode(VIOsPAPRDevice *dev, void *fdt, int node_off)
936 {
937     int ret;
938 
939     ret = fdt_setprop_cell(fdt, node_off, "#address-cells", 2);
940     if (ret < 0) {
941         return ret;
942     }
943 
944     ret = fdt_setprop_cell(fdt, node_off, "#size-cells", 0);
945     if (ret < 0) {
946         return ret;
947     }
948 
949     return 0;
950 }
951 
952 static Property spapr_vscsi_properties[] = {
953     DEFINE_SPAPR_PROPERTIES(VSCSIState, vdev),
954     DEFINE_PROP_END_OF_LIST(),
955 };
956 
957 static void spapr_vscsi_class_init(ObjectClass *klass, void *data)
958 {
959     DeviceClass *dc = DEVICE_CLASS(klass);
960     VIOsPAPRDeviceClass *k = VIO_SPAPR_DEVICE_CLASS(klass);
961 
962     k->init = spapr_vscsi_init;
963     k->reset = spapr_vscsi_reset;
964     k->devnode = spapr_vscsi_devnode;
965     k->dt_name = "v-scsi";
966     k->dt_type = "vscsi";
967     k->dt_compatible = "IBM,v-scsi";
968     k->signal_mask = 0x00000001;
969     dc->props = spapr_vscsi_properties;
970     k->rtce_window_size = 0x10000000;
971 }
972 
973 static const TypeInfo spapr_vscsi_info = {
974     .name          = TYPE_VIO_SPAPR_VSCSI_DEVICE,
975     .parent        = TYPE_VIO_SPAPR_DEVICE,
976     .instance_size = sizeof(VSCSIState),
977     .class_init    = spapr_vscsi_class_init,
978 };
979 
980 static void spapr_vscsi_register_types(void)
981 {
982     type_register_static(&spapr_vscsi_info);
983 }
984 
985 type_init(spapr_vscsi_register_types)
986