1 /*
2 * Linux driver for VMware's para-virtualized SCSI HBA.
3 *
4 * Copyright (C) 2008-2014, VMware, Inc. All Rights Reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; version 2 of the License and no later version.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
13 * NON INFRINGEMENT. See the GNU General Public License for more
14 * details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 */
21
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/interrupt.h>
25 #include <linux/slab.h>
26 #include <linux/workqueue.h>
27 #include <linux/pci.h>
28
29 #include <scsi/scsi.h>
30 #include <scsi/scsi_host.h>
31 #include <scsi/scsi_cmnd.h>
32 #include <scsi/scsi_device.h>
33 #include <scsi/scsi_tcq.h>
34
35 #include "vmw_pvscsi.h"
36
37 #define PVSCSI_LINUX_DRIVER_DESC "VMware PVSCSI driver"
38
39 MODULE_DESCRIPTION(PVSCSI_LINUX_DRIVER_DESC);
40 MODULE_AUTHOR("VMware, Inc.");
41 MODULE_LICENSE("GPL");
42 MODULE_VERSION(PVSCSI_DRIVER_VERSION_STRING);
43
44 #define PVSCSI_DEFAULT_NUM_PAGES_PER_RING 8
45 #define PVSCSI_DEFAULT_NUM_PAGES_MSG_RING 1
46 #define PVSCSI_DEFAULT_QUEUE_DEPTH 254
47 #define SGL_SIZE PAGE_SIZE
48
49 struct pvscsi_sg_list {
50 struct PVSCSISGElement sge[PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT];
51 };
52
53 struct pvscsi_ctx {
54 /*
55 * The index of the context in cmd_map serves as the context ID for a
56 * 1-to-1 mapping completions back to requests.
57 */
58 struct scsi_cmnd *cmd;
59 struct pvscsi_sg_list *sgl;
60 struct list_head list;
61 dma_addr_t dataPA;
62 dma_addr_t sensePA;
63 dma_addr_t sglPA;
64 struct completion *abort_cmp;
65 };
66
67 struct pvscsi_adapter {
68 char *mmioBase;
69 u8 rev;
70 bool use_msg;
71 bool use_req_threshold;
72
73 spinlock_t hw_lock;
74
75 struct workqueue_struct *workqueue;
76 struct work_struct work;
77
78 struct PVSCSIRingReqDesc *req_ring;
79 unsigned req_pages;
80 unsigned req_depth;
81 dma_addr_t reqRingPA;
82
83 struct PVSCSIRingCmpDesc *cmp_ring;
84 unsigned cmp_pages;
85 dma_addr_t cmpRingPA;
86
87 struct PVSCSIRingMsgDesc *msg_ring;
88 unsigned msg_pages;
89 dma_addr_t msgRingPA;
90
91 struct PVSCSIRingsState *rings_state;
92 dma_addr_t ringStatePA;
93
94 struct pci_dev *dev;
95 struct Scsi_Host *host;
96
97 struct list_head cmd_pool;
98 struct pvscsi_ctx *cmd_map;
99 };
100
101
102 /* Command line parameters */
103 static int pvscsi_ring_pages;
104 static int pvscsi_msg_ring_pages = PVSCSI_DEFAULT_NUM_PAGES_MSG_RING;
105 static int pvscsi_cmd_per_lun = PVSCSI_DEFAULT_QUEUE_DEPTH;
106 static bool pvscsi_disable_msi;
107 static bool pvscsi_disable_msix;
108 static bool pvscsi_use_msg = true;
109 static bool pvscsi_use_req_threshold = true;
110
111 #define PVSCSI_RW (S_IRUSR | S_IWUSR)
112
113 module_param_named(ring_pages, pvscsi_ring_pages, int, PVSCSI_RW);
114 MODULE_PARM_DESC(ring_pages, "Number of pages per req/cmp ring - (default="
115 __stringify(PVSCSI_DEFAULT_NUM_PAGES_PER_RING)
116 "[up to 16 targets],"
117 __stringify(PVSCSI_SETUP_RINGS_MAX_NUM_PAGES)
118 "[for 16+ targets])");
119
120 module_param_named(msg_ring_pages, pvscsi_msg_ring_pages, int, PVSCSI_RW);
121 MODULE_PARM_DESC(msg_ring_pages, "Number of pages for the msg ring - (default="
122 __stringify(PVSCSI_DEFAULT_NUM_PAGES_MSG_RING) ")");
123
124 module_param_named(cmd_per_lun, pvscsi_cmd_per_lun, int, PVSCSI_RW);
125 MODULE_PARM_DESC(cmd_per_lun, "Maximum commands per lun - (default="
126 __stringify(PVSCSI_DEFAULT_QUEUE_DEPTH) ")");
127
128 module_param_named(disable_msi, pvscsi_disable_msi, bool, PVSCSI_RW);
129 MODULE_PARM_DESC(disable_msi, "Disable MSI use in driver - (default=0)");
130
131 module_param_named(disable_msix, pvscsi_disable_msix, bool, PVSCSI_RW);
132 MODULE_PARM_DESC(disable_msix, "Disable MSI-X use in driver - (default=0)");
133
134 module_param_named(use_msg, pvscsi_use_msg, bool, PVSCSI_RW);
135 MODULE_PARM_DESC(use_msg, "Use msg ring when available - (default=1)");
136
137 module_param_named(use_req_threshold, pvscsi_use_req_threshold,
138 bool, PVSCSI_RW);
139 MODULE_PARM_DESC(use_req_threshold, "Use driver-based request coalescing if configured - (default=1)");
140
141 static const struct pci_device_id pvscsi_pci_tbl[] = {
142 { PCI_VDEVICE(VMWARE, PCI_DEVICE_ID_VMWARE_PVSCSI) },
143 { 0 }
144 };
145
146 MODULE_DEVICE_TABLE(pci, pvscsi_pci_tbl);
147
148 static struct device *
pvscsi_dev(const struct pvscsi_adapter * adapter)149 pvscsi_dev(const struct pvscsi_adapter *adapter)
150 {
151 return &(adapter->dev->dev);
152 }
153
154 static struct pvscsi_ctx *
pvscsi_find_context(const struct pvscsi_adapter * adapter,struct scsi_cmnd * cmd)155 pvscsi_find_context(const struct pvscsi_adapter *adapter, struct scsi_cmnd *cmd)
156 {
157 struct pvscsi_ctx *ctx, *end;
158
159 end = &adapter->cmd_map[adapter->req_depth];
160 for (ctx = adapter->cmd_map; ctx < end; ctx++)
161 if (ctx->cmd == cmd)
162 return ctx;
163
164 return NULL;
165 }
166
167 static struct pvscsi_ctx *
pvscsi_acquire_context(struct pvscsi_adapter * adapter,struct scsi_cmnd * cmd)168 pvscsi_acquire_context(struct pvscsi_adapter *adapter, struct scsi_cmnd *cmd)
169 {
170 struct pvscsi_ctx *ctx;
171
172 if (list_empty(&adapter->cmd_pool))
173 return NULL;
174
175 ctx = list_first_entry(&adapter->cmd_pool, struct pvscsi_ctx, list);
176 ctx->cmd = cmd;
177 list_del(&ctx->list);
178
179 return ctx;
180 }
181
pvscsi_release_context(struct pvscsi_adapter * adapter,struct pvscsi_ctx * ctx)182 static void pvscsi_release_context(struct pvscsi_adapter *adapter,
183 struct pvscsi_ctx *ctx)
184 {
185 ctx->cmd = NULL;
186 ctx->abort_cmp = NULL;
187 list_add(&ctx->list, &adapter->cmd_pool);
188 }
189
190 /*
191 * Map a pvscsi_ctx struct to a context ID field value; we map to a simple
192 * non-zero integer. ctx always points to an entry in cmd_map array, hence
193 * the return value is always >=1.
194 */
pvscsi_map_context(const struct pvscsi_adapter * adapter,const struct pvscsi_ctx * ctx)195 static u64 pvscsi_map_context(const struct pvscsi_adapter *adapter,
196 const struct pvscsi_ctx *ctx)
197 {
198 return ctx - adapter->cmd_map + 1;
199 }
200
201 static struct pvscsi_ctx *
pvscsi_get_context(const struct pvscsi_adapter * adapter,u64 context)202 pvscsi_get_context(const struct pvscsi_adapter *adapter, u64 context)
203 {
204 return &adapter->cmd_map[context - 1];
205 }
206
pvscsi_reg_write(const struct pvscsi_adapter * adapter,u32 offset,u32 val)207 static void pvscsi_reg_write(const struct pvscsi_adapter *adapter,
208 u32 offset, u32 val)
209 {
210 writel(val, adapter->mmioBase + offset);
211 }
212
pvscsi_reg_read(const struct pvscsi_adapter * adapter,u32 offset)213 static u32 pvscsi_reg_read(const struct pvscsi_adapter *adapter, u32 offset)
214 {
215 return readl(adapter->mmioBase + offset);
216 }
217
pvscsi_read_intr_status(const struct pvscsi_adapter * adapter)218 static u32 pvscsi_read_intr_status(const struct pvscsi_adapter *adapter)
219 {
220 return pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_INTR_STATUS);
221 }
222
pvscsi_write_intr_status(const struct pvscsi_adapter * adapter,u32 val)223 static void pvscsi_write_intr_status(const struct pvscsi_adapter *adapter,
224 u32 val)
225 {
226 pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_STATUS, val);
227 }
228
pvscsi_unmask_intr(const struct pvscsi_adapter * adapter)229 static void pvscsi_unmask_intr(const struct pvscsi_adapter *adapter)
230 {
231 u32 intr_bits;
232
233 intr_bits = PVSCSI_INTR_CMPL_MASK;
234 if (adapter->use_msg)
235 intr_bits |= PVSCSI_INTR_MSG_MASK;
236
237 pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_MASK, intr_bits);
238 }
239
pvscsi_mask_intr(const struct pvscsi_adapter * adapter)240 static void pvscsi_mask_intr(const struct pvscsi_adapter *adapter)
241 {
242 pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_MASK, 0);
243 }
244
pvscsi_write_cmd_desc(const struct pvscsi_adapter * adapter,u32 cmd,const void * desc,size_t len)245 static void pvscsi_write_cmd_desc(const struct pvscsi_adapter *adapter,
246 u32 cmd, const void *desc, size_t len)
247 {
248 const u32 *ptr = desc;
249 size_t i;
250
251 len /= sizeof(*ptr);
252 pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND, cmd);
253 for (i = 0; i < len; i++)
254 pvscsi_reg_write(adapter,
255 PVSCSI_REG_OFFSET_COMMAND_DATA, ptr[i]);
256 }
257
pvscsi_abort_cmd(const struct pvscsi_adapter * adapter,const struct pvscsi_ctx * ctx)258 static void pvscsi_abort_cmd(const struct pvscsi_adapter *adapter,
259 const struct pvscsi_ctx *ctx)
260 {
261 struct PVSCSICmdDescAbortCmd cmd = { 0 };
262
263 cmd.target = ctx->cmd->device->id;
264 cmd.context = pvscsi_map_context(adapter, ctx);
265
266 pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_ABORT_CMD, &cmd, sizeof(cmd));
267 }
268
pvscsi_kick_rw_io(const struct pvscsi_adapter * adapter)269 static void pvscsi_kick_rw_io(const struct pvscsi_adapter *adapter)
270 {
271 pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_KICK_RW_IO, 0);
272 }
273
pvscsi_process_request_ring(const struct pvscsi_adapter * adapter)274 static void pvscsi_process_request_ring(const struct pvscsi_adapter *adapter)
275 {
276 pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_KICK_NON_RW_IO, 0);
277 }
278
scsi_is_rw(unsigned char op)279 static int scsi_is_rw(unsigned char op)
280 {
281 return op == READ_6 || op == WRITE_6 ||
282 op == READ_10 || op == WRITE_10 ||
283 op == READ_12 || op == WRITE_12 ||
284 op == READ_16 || op == WRITE_16;
285 }
286
pvscsi_kick_io(const struct pvscsi_adapter * adapter,unsigned char op)287 static void pvscsi_kick_io(const struct pvscsi_adapter *adapter,
288 unsigned char op)
289 {
290 if (scsi_is_rw(op)) {
291 struct PVSCSIRingsState *s = adapter->rings_state;
292
293 if (!adapter->use_req_threshold ||
294 s->reqProdIdx - s->reqConsIdx >= s->reqCallThreshold)
295 pvscsi_kick_rw_io(adapter);
296 } else {
297 pvscsi_process_request_ring(adapter);
298 }
299 }
300
ll_adapter_reset(const struct pvscsi_adapter * adapter)301 static void ll_adapter_reset(const struct pvscsi_adapter *adapter)
302 {
303 dev_dbg(pvscsi_dev(adapter), "Adapter Reset on %p\n", adapter);
304
305 pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_ADAPTER_RESET, NULL, 0);
306 }
307
ll_bus_reset(const struct pvscsi_adapter * adapter)308 static void ll_bus_reset(const struct pvscsi_adapter *adapter)
309 {
310 dev_dbg(pvscsi_dev(adapter), "Resetting bus on %p\n", adapter);
311
312 pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_RESET_BUS, NULL, 0);
313 }
314
ll_device_reset(const struct pvscsi_adapter * adapter,u32 target)315 static void ll_device_reset(const struct pvscsi_adapter *adapter, u32 target)
316 {
317 struct PVSCSICmdDescResetDevice cmd = { 0 };
318
319 dev_dbg(pvscsi_dev(adapter), "Resetting device: target=%u\n", target);
320
321 cmd.target = target;
322
323 pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_RESET_DEVICE,
324 &cmd, sizeof(cmd));
325 }
326
pvscsi_create_sg(struct pvscsi_ctx * ctx,struct scatterlist * sg,unsigned count)327 static void pvscsi_create_sg(struct pvscsi_ctx *ctx,
328 struct scatterlist *sg, unsigned count)
329 {
330 unsigned i;
331 struct PVSCSISGElement *sge;
332
333 BUG_ON(count > PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT);
334
335 sge = &ctx->sgl->sge[0];
336 for (i = 0; i < count; i++, sg = sg_next(sg)) {
337 sge[i].addr = sg_dma_address(sg);
338 sge[i].length = sg_dma_len(sg);
339 sge[i].flags = 0;
340 }
341 }
342
343 /*
344 * Map all data buffers for a command into PCI space and
345 * setup the scatter/gather list if needed.
346 */
pvscsi_map_buffers(struct pvscsi_adapter * adapter,struct pvscsi_ctx * ctx,struct scsi_cmnd * cmd,struct PVSCSIRingReqDesc * e)347 static int pvscsi_map_buffers(struct pvscsi_adapter *adapter,
348 struct pvscsi_ctx *ctx, struct scsi_cmnd *cmd,
349 struct PVSCSIRingReqDesc *e)
350 {
351 unsigned count;
352 unsigned bufflen = scsi_bufflen(cmd);
353 struct scatterlist *sg;
354
355 e->dataLen = bufflen;
356 e->dataAddr = 0;
357 if (bufflen == 0)
358 return 0;
359
360 sg = scsi_sglist(cmd);
361 count = scsi_sg_count(cmd);
362 if (count != 0) {
363 int segs = scsi_dma_map(cmd);
364
365 if (segs == -ENOMEM) {
366 scmd_printk(KERN_DEBUG, cmd,
367 "vmw_pvscsi: Failed to map cmd sglist for DMA.\n");
368 return -ENOMEM;
369 } else if (segs > 1) {
370 pvscsi_create_sg(ctx, sg, segs);
371
372 e->flags |= PVSCSI_FLAG_CMD_WITH_SG_LIST;
373 ctx->sglPA = dma_map_single(&adapter->dev->dev,
374 ctx->sgl, SGL_SIZE, DMA_TO_DEVICE);
375 if (dma_mapping_error(&adapter->dev->dev, ctx->sglPA)) {
376 scmd_printk(KERN_ERR, cmd,
377 "vmw_pvscsi: Failed to map ctx sglist for DMA.\n");
378 scsi_dma_unmap(cmd);
379 ctx->sglPA = 0;
380 return -ENOMEM;
381 }
382 e->dataAddr = ctx->sglPA;
383 } else
384 e->dataAddr = sg_dma_address(sg);
385 } else {
386 /*
387 * In case there is no S/G list, scsi_sglist points
388 * directly to the buffer.
389 */
390 ctx->dataPA = dma_map_single(&adapter->dev->dev, sg, bufflen,
391 cmd->sc_data_direction);
392 if (dma_mapping_error(&adapter->dev->dev, ctx->dataPA)) {
393 scmd_printk(KERN_DEBUG, cmd,
394 "vmw_pvscsi: Failed to map direct data buffer for DMA.\n");
395 return -ENOMEM;
396 }
397 e->dataAddr = ctx->dataPA;
398 }
399
400 return 0;
401 }
402
403 /*
404 * The device incorrectly doesn't clear the first byte of the sense
405 * buffer in some cases. We have to do it ourselves.
406 * Otherwise we run into trouble when SWIOTLB is forced.
407 */
pvscsi_patch_sense(struct scsi_cmnd * cmd)408 static void pvscsi_patch_sense(struct scsi_cmnd *cmd)
409 {
410 if (cmd->sense_buffer)
411 cmd->sense_buffer[0] = 0;
412 }
413
pvscsi_unmap_buffers(const struct pvscsi_adapter * adapter,struct pvscsi_ctx * ctx)414 static void pvscsi_unmap_buffers(const struct pvscsi_adapter *adapter,
415 struct pvscsi_ctx *ctx)
416 {
417 struct scsi_cmnd *cmd;
418 unsigned bufflen;
419
420 cmd = ctx->cmd;
421 bufflen = scsi_bufflen(cmd);
422
423 if (bufflen != 0) {
424 unsigned count = scsi_sg_count(cmd);
425
426 if (count != 0) {
427 scsi_dma_unmap(cmd);
428 if (ctx->sglPA) {
429 dma_unmap_single(&adapter->dev->dev, ctx->sglPA,
430 SGL_SIZE, DMA_TO_DEVICE);
431 ctx->sglPA = 0;
432 }
433 } else
434 dma_unmap_single(&adapter->dev->dev, ctx->dataPA,
435 bufflen, cmd->sc_data_direction);
436 }
437 if (cmd->sense_buffer)
438 dma_unmap_single(&adapter->dev->dev, ctx->sensePA,
439 SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
440 }
441
pvscsi_allocate_rings(struct pvscsi_adapter * adapter)442 static int pvscsi_allocate_rings(struct pvscsi_adapter *adapter)
443 {
444 adapter->rings_state = dma_alloc_coherent(&adapter->dev->dev, PAGE_SIZE,
445 &adapter->ringStatePA, GFP_KERNEL);
446 if (!adapter->rings_state)
447 return -ENOMEM;
448
449 adapter->req_pages = min(PVSCSI_MAX_NUM_PAGES_REQ_RING,
450 pvscsi_ring_pages);
451 adapter->req_depth = adapter->req_pages
452 * PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
453 adapter->req_ring = dma_alloc_coherent(&adapter->dev->dev,
454 adapter->req_pages * PAGE_SIZE, &adapter->reqRingPA,
455 GFP_KERNEL);
456 if (!adapter->req_ring)
457 return -ENOMEM;
458
459 adapter->cmp_pages = min(PVSCSI_MAX_NUM_PAGES_CMP_RING,
460 pvscsi_ring_pages);
461 adapter->cmp_ring = dma_alloc_coherent(&adapter->dev->dev,
462 adapter->cmp_pages * PAGE_SIZE, &adapter->cmpRingPA,
463 GFP_KERNEL);
464 if (!adapter->cmp_ring)
465 return -ENOMEM;
466
467 BUG_ON(!IS_ALIGNED(adapter->ringStatePA, PAGE_SIZE));
468 BUG_ON(!IS_ALIGNED(adapter->reqRingPA, PAGE_SIZE));
469 BUG_ON(!IS_ALIGNED(adapter->cmpRingPA, PAGE_SIZE));
470
471 if (!adapter->use_msg)
472 return 0;
473
474 adapter->msg_pages = min(PVSCSI_MAX_NUM_PAGES_MSG_RING,
475 pvscsi_msg_ring_pages);
476 adapter->msg_ring = dma_alloc_coherent(&adapter->dev->dev,
477 adapter->msg_pages * PAGE_SIZE, &adapter->msgRingPA,
478 GFP_KERNEL);
479 if (!adapter->msg_ring)
480 return -ENOMEM;
481 BUG_ON(!IS_ALIGNED(adapter->msgRingPA, PAGE_SIZE));
482
483 return 0;
484 }
485
pvscsi_setup_all_rings(const struct pvscsi_adapter * adapter)486 static void pvscsi_setup_all_rings(const struct pvscsi_adapter *adapter)
487 {
488 struct PVSCSICmdDescSetupRings cmd = { 0 };
489 dma_addr_t base;
490 unsigned i;
491
492 cmd.ringsStatePPN = adapter->ringStatePA >> PAGE_SHIFT;
493 cmd.reqRingNumPages = adapter->req_pages;
494 cmd.cmpRingNumPages = adapter->cmp_pages;
495
496 base = adapter->reqRingPA;
497 for (i = 0; i < adapter->req_pages; i++) {
498 cmd.reqRingPPNs[i] = base >> PAGE_SHIFT;
499 base += PAGE_SIZE;
500 }
501
502 base = adapter->cmpRingPA;
503 for (i = 0; i < adapter->cmp_pages; i++) {
504 cmd.cmpRingPPNs[i] = base >> PAGE_SHIFT;
505 base += PAGE_SIZE;
506 }
507
508 memset(adapter->rings_state, 0, PAGE_SIZE);
509 memset(adapter->req_ring, 0, adapter->req_pages * PAGE_SIZE);
510 memset(adapter->cmp_ring, 0, adapter->cmp_pages * PAGE_SIZE);
511
512 pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_RINGS,
513 &cmd, sizeof(cmd));
514
515 if (adapter->use_msg) {
516 struct PVSCSICmdDescSetupMsgRing cmd_msg = { 0 };
517
518 cmd_msg.numPages = adapter->msg_pages;
519
520 base = adapter->msgRingPA;
521 for (i = 0; i < adapter->msg_pages; i++) {
522 cmd_msg.ringPPNs[i] = base >> PAGE_SHIFT;
523 base += PAGE_SIZE;
524 }
525 memset(adapter->msg_ring, 0, adapter->msg_pages * PAGE_SIZE);
526
527 pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_MSG_RING,
528 &cmd_msg, sizeof(cmd_msg));
529 }
530 }
531
pvscsi_change_queue_depth(struct scsi_device * sdev,int qdepth)532 static int pvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
533 {
534 if (!sdev->tagged_supported)
535 qdepth = 1;
536 return scsi_change_queue_depth(sdev, qdepth);
537 }
538
539 /*
540 * Pull a completion descriptor off and pass the completion back
541 * to the SCSI mid layer.
542 */
pvscsi_complete_request(struct pvscsi_adapter * adapter,const struct PVSCSIRingCmpDesc * e)543 static void pvscsi_complete_request(struct pvscsi_adapter *adapter,
544 const struct PVSCSIRingCmpDesc *e)
545 {
546 struct pvscsi_ctx *ctx;
547 struct scsi_cmnd *cmd;
548 struct completion *abort_cmp;
549 u32 btstat = e->hostStatus;
550 u32 sdstat = e->scsiStatus;
551
552 ctx = pvscsi_get_context(adapter, e->context);
553 cmd = ctx->cmd;
554 abort_cmp = ctx->abort_cmp;
555 pvscsi_unmap_buffers(adapter, ctx);
556 if (sdstat != SAM_STAT_CHECK_CONDITION)
557 pvscsi_patch_sense(cmd);
558 pvscsi_release_context(adapter, ctx);
559 if (abort_cmp) {
560 /*
561 * The command was requested to be aborted. Just signal that
562 * the request completed and swallow the actual cmd completion
563 * here. The abort handler will post a completion for this
564 * command indicating that it got successfully aborted.
565 */
566 complete(abort_cmp);
567 return;
568 }
569
570 cmd->result = 0;
571 if (sdstat != SAM_STAT_GOOD &&
572 (btstat == BTSTAT_SUCCESS ||
573 btstat == BTSTAT_LINKED_COMMAND_COMPLETED ||
574 btstat == BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG)) {
575 if (sdstat == SAM_STAT_COMMAND_TERMINATED) {
576 cmd->result = (DID_RESET << 16);
577 } else {
578 cmd->result = (DID_OK << 16) | sdstat;
579 }
580 } else
581 switch (btstat) {
582 case BTSTAT_SUCCESS:
583 case BTSTAT_LINKED_COMMAND_COMPLETED:
584 case BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG:
585 /*
586 * Commands like INQUIRY may transfer less data than
587 * requested by the initiator via bufflen. Set residual
588 * count to make upper layer aware of the actual amount
589 * of data returned. There are cases when controller
590 * returns zero dataLen with non zero data - do not set
591 * residual count in that case.
592 */
593 if (e->dataLen && (e->dataLen < scsi_bufflen(cmd)))
594 scsi_set_resid(cmd, scsi_bufflen(cmd) - e->dataLen);
595 cmd->result = (DID_OK << 16);
596 break;
597
598 case BTSTAT_DATARUN:
599 case BTSTAT_DATA_UNDERRUN:
600 /* Report residual data in underruns */
601 scsi_set_resid(cmd, scsi_bufflen(cmd) - e->dataLen);
602 cmd->result = (DID_ERROR << 16);
603 break;
604
605 case BTSTAT_SELTIMEO:
606 /* Our emulation returns this for non-connected devs */
607 cmd->result = (DID_BAD_TARGET << 16);
608 break;
609
610 case BTSTAT_LUNMISMATCH:
611 case BTSTAT_TAGREJECT:
612 case BTSTAT_BADMSG:
613 case BTSTAT_HAHARDWARE:
614 case BTSTAT_INVPHASE:
615 case BTSTAT_HATIMEOUT:
616 case BTSTAT_NORESPONSE:
617 case BTSTAT_DISCONNECT:
618 case BTSTAT_HASOFTWARE:
619 case BTSTAT_BUSFREE:
620 case BTSTAT_SENSFAILED:
621 cmd->result |= (DID_ERROR << 16);
622 break;
623
624 case BTSTAT_SENTRST:
625 case BTSTAT_RECVRST:
626 case BTSTAT_BUSRESET:
627 cmd->result = (DID_RESET << 16);
628 break;
629
630 case BTSTAT_ABORTQUEUE:
631 cmd->result = (DID_BUS_BUSY << 16);
632 break;
633
634 case BTSTAT_SCSIPARITY:
635 cmd->result = (DID_PARITY << 16);
636 break;
637
638 default:
639 cmd->result = (DID_ERROR << 16);
640 scmd_printk(KERN_DEBUG, cmd,
641 "Unknown completion status: 0x%x\n",
642 btstat);
643 }
644
645 dev_dbg(&cmd->device->sdev_gendev,
646 "cmd=%p %x ctx=%p result=0x%x status=0x%x,%x\n",
647 cmd, cmd->cmnd[0], ctx, cmd->result, btstat, sdstat);
648
649 cmd->scsi_done(cmd);
650 }
651
652 /*
653 * barrier usage : Since the PVSCSI device is emulated, there could be cases
654 * where we may want to serialize some accesses between the driver and the
655 * emulation layer. We use compiler barriers instead of the more expensive
656 * memory barriers because PVSCSI is only supported on X86 which has strong
657 * memory access ordering.
658 */
pvscsi_process_completion_ring(struct pvscsi_adapter * adapter)659 static void pvscsi_process_completion_ring(struct pvscsi_adapter *adapter)
660 {
661 struct PVSCSIRingsState *s = adapter->rings_state;
662 struct PVSCSIRingCmpDesc *ring = adapter->cmp_ring;
663 u32 cmp_entries = s->cmpNumEntriesLog2;
664
665 while (s->cmpConsIdx != s->cmpProdIdx) {
666 struct PVSCSIRingCmpDesc *e = ring + (s->cmpConsIdx &
667 MASK(cmp_entries));
668 /*
669 * This barrier() ensures that *e is not dereferenced while
670 * the device emulation still writes data into the slot.
671 * Since the device emulation advances s->cmpProdIdx only after
672 * updating the slot we want to check it first.
673 */
674 barrier();
675 pvscsi_complete_request(adapter, e);
676 /*
677 * This barrier() ensures that compiler doesn't reorder write
678 * to s->cmpConsIdx before the read of (*e) inside
679 * pvscsi_complete_request. Otherwise, device emulation may
680 * overwrite *e before we had a chance to read it.
681 */
682 barrier();
683 s->cmpConsIdx++;
684 }
685 }
686
687 /*
688 * Translate a Linux SCSI request into a request ring entry.
689 */
pvscsi_queue_ring(struct pvscsi_adapter * adapter,struct pvscsi_ctx * ctx,struct scsi_cmnd * cmd)690 static int pvscsi_queue_ring(struct pvscsi_adapter *adapter,
691 struct pvscsi_ctx *ctx, struct scsi_cmnd *cmd)
692 {
693 struct PVSCSIRingsState *s;
694 struct PVSCSIRingReqDesc *e;
695 struct scsi_device *sdev;
696 u32 req_entries;
697
698 s = adapter->rings_state;
699 sdev = cmd->device;
700 req_entries = s->reqNumEntriesLog2;
701
702 /*
703 * If this condition holds, we might have room on the request ring, but
704 * we might not have room on the completion ring for the response.
705 * However, we have already ruled out this possibility - we would not
706 * have successfully allocated a context if it were true, since we only
707 * have one context per request entry. Check for it anyway, since it
708 * would be a serious bug.
709 */
710 if (s->reqProdIdx - s->cmpConsIdx >= 1 << req_entries) {
711 scmd_printk(KERN_ERR, cmd, "vmw_pvscsi: "
712 "ring full: reqProdIdx=%d cmpConsIdx=%d\n",
713 s->reqProdIdx, s->cmpConsIdx);
714 return -1;
715 }
716
717 e = adapter->req_ring + (s->reqProdIdx & MASK(req_entries));
718
719 e->bus = sdev->channel;
720 e->target = sdev->id;
721 memset(e->lun, 0, sizeof(e->lun));
722 e->lun[1] = sdev->lun;
723
724 if (cmd->sense_buffer) {
725 ctx->sensePA = dma_map_single(&adapter->dev->dev,
726 cmd->sense_buffer, SCSI_SENSE_BUFFERSIZE,
727 DMA_FROM_DEVICE);
728 if (dma_mapping_error(&adapter->dev->dev, ctx->sensePA)) {
729 scmd_printk(KERN_DEBUG, cmd,
730 "vmw_pvscsi: Failed to map sense buffer for DMA.\n");
731 ctx->sensePA = 0;
732 return -ENOMEM;
733 }
734 e->senseAddr = ctx->sensePA;
735 e->senseLen = SCSI_SENSE_BUFFERSIZE;
736 } else {
737 e->senseLen = 0;
738 e->senseAddr = 0;
739 }
740 e->cdbLen = cmd->cmd_len;
741 e->vcpuHint = smp_processor_id();
742 memcpy(e->cdb, cmd->cmnd, e->cdbLen);
743
744 e->tag = SIMPLE_QUEUE_TAG;
745
746 if (cmd->sc_data_direction == DMA_FROM_DEVICE)
747 e->flags = PVSCSI_FLAG_CMD_DIR_TOHOST;
748 else if (cmd->sc_data_direction == DMA_TO_DEVICE)
749 e->flags = PVSCSI_FLAG_CMD_DIR_TODEVICE;
750 else if (cmd->sc_data_direction == DMA_NONE)
751 e->flags = PVSCSI_FLAG_CMD_DIR_NONE;
752 else
753 e->flags = 0;
754
755 if (pvscsi_map_buffers(adapter, ctx, cmd, e) != 0) {
756 if (cmd->sense_buffer) {
757 dma_unmap_single(&adapter->dev->dev, ctx->sensePA,
758 SCSI_SENSE_BUFFERSIZE,
759 DMA_FROM_DEVICE);
760 ctx->sensePA = 0;
761 }
762 return -ENOMEM;
763 }
764
765 e->context = pvscsi_map_context(adapter, ctx);
766
767 barrier();
768
769 s->reqProdIdx++;
770
771 return 0;
772 }
773
pvscsi_queue_lck(struct scsi_cmnd * cmd,void (* done)(struct scsi_cmnd *))774 static int pvscsi_queue_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
775 {
776 struct Scsi_Host *host = cmd->device->host;
777 struct pvscsi_adapter *adapter = shost_priv(host);
778 struct pvscsi_ctx *ctx;
779 unsigned long flags;
780 unsigned char op;
781
782 spin_lock_irqsave(&adapter->hw_lock, flags);
783
784 ctx = pvscsi_acquire_context(adapter, cmd);
785 if (!ctx || pvscsi_queue_ring(adapter, ctx, cmd) != 0) {
786 if (ctx)
787 pvscsi_release_context(adapter, ctx);
788 spin_unlock_irqrestore(&adapter->hw_lock, flags);
789 return SCSI_MLQUEUE_HOST_BUSY;
790 }
791
792 cmd->scsi_done = done;
793 op = cmd->cmnd[0];
794
795 dev_dbg(&cmd->device->sdev_gendev,
796 "queued cmd %p, ctx %p, op=%x\n", cmd, ctx, op);
797
798 spin_unlock_irqrestore(&adapter->hw_lock, flags);
799
800 pvscsi_kick_io(adapter, op);
801
802 return 0;
803 }
804
DEF_SCSI_QCMD(pvscsi_queue)805 static DEF_SCSI_QCMD(pvscsi_queue)
806
807 static int pvscsi_abort(struct scsi_cmnd *cmd)
808 {
809 struct pvscsi_adapter *adapter = shost_priv(cmd->device->host);
810 struct pvscsi_ctx *ctx;
811 unsigned long flags;
812 int result = SUCCESS;
813 DECLARE_COMPLETION_ONSTACK(abort_cmp);
814 int done;
815
816 scmd_printk(KERN_DEBUG, cmd, "task abort on host %u, %p\n",
817 adapter->host->host_no, cmd);
818
819 spin_lock_irqsave(&adapter->hw_lock, flags);
820
821 /*
822 * Poll the completion ring first - we might be trying to abort
823 * a command that is waiting to be dispatched in the completion ring.
824 */
825 pvscsi_process_completion_ring(adapter);
826
827 /*
828 * If there is no context for the command, it either already succeeded
829 * or else was never properly issued. Not our problem.
830 */
831 ctx = pvscsi_find_context(adapter, cmd);
832 if (!ctx) {
833 scmd_printk(KERN_DEBUG, cmd, "Failed to abort cmd %p\n", cmd);
834 goto out;
835 }
836
837 /*
838 * Mark that the command has been requested to be aborted and issue
839 * the abort.
840 */
841 ctx->abort_cmp = &abort_cmp;
842
843 pvscsi_abort_cmd(adapter, ctx);
844 spin_unlock_irqrestore(&adapter->hw_lock, flags);
845 /* Wait for 2 secs for the completion. */
846 done = wait_for_completion_timeout(&abort_cmp, msecs_to_jiffies(2000));
847 spin_lock_irqsave(&adapter->hw_lock, flags);
848
849 if (!done) {
850 /*
851 * Failed to abort the command, unmark the fact that it
852 * was requested to be aborted.
853 */
854 ctx->abort_cmp = NULL;
855 result = FAILED;
856 scmd_printk(KERN_DEBUG, cmd,
857 "Failed to get completion for aborted cmd %p\n",
858 cmd);
859 goto out;
860 }
861
862 /*
863 * Successfully aborted the command.
864 */
865 cmd->result = (DID_ABORT << 16);
866 cmd->scsi_done(cmd);
867
868 out:
869 spin_unlock_irqrestore(&adapter->hw_lock, flags);
870 return result;
871 }
872
873 /*
874 * Abort all outstanding requests. This is only safe to use if the completion
875 * ring will never be walked again or the device has been reset, because it
876 * destroys the 1-1 mapping between context field passed to emulation and our
877 * request structure.
878 */
pvscsi_reset_all(struct pvscsi_adapter * adapter)879 static void pvscsi_reset_all(struct pvscsi_adapter *adapter)
880 {
881 unsigned i;
882
883 for (i = 0; i < adapter->req_depth; i++) {
884 struct pvscsi_ctx *ctx = &adapter->cmd_map[i];
885 struct scsi_cmnd *cmd = ctx->cmd;
886 if (cmd) {
887 scmd_printk(KERN_ERR, cmd,
888 "Forced reset on cmd %p\n", cmd);
889 pvscsi_unmap_buffers(adapter, ctx);
890 pvscsi_patch_sense(cmd);
891 pvscsi_release_context(adapter, ctx);
892 cmd->result = (DID_RESET << 16);
893 cmd->scsi_done(cmd);
894 }
895 }
896 }
897
pvscsi_host_reset(struct scsi_cmnd * cmd)898 static int pvscsi_host_reset(struct scsi_cmnd *cmd)
899 {
900 struct Scsi_Host *host = cmd->device->host;
901 struct pvscsi_adapter *adapter = shost_priv(host);
902 unsigned long flags;
903 bool use_msg;
904
905 scmd_printk(KERN_INFO, cmd, "SCSI Host reset\n");
906
907 spin_lock_irqsave(&adapter->hw_lock, flags);
908
909 use_msg = adapter->use_msg;
910
911 if (use_msg) {
912 adapter->use_msg = false;
913 spin_unlock_irqrestore(&adapter->hw_lock, flags);
914
915 /*
916 * Now that we know that the ISR won't add more work on the
917 * workqueue we can safely flush any outstanding work.
918 */
919 flush_workqueue(adapter->workqueue);
920 spin_lock_irqsave(&adapter->hw_lock, flags);
921 }
922
923 /*
924 * We're going to tear down the entire ring structure and set it back
925 * up, so stalling new requests until all completions are flushed and
926 * the rings are back in place.
927 */
928
929 pvscsi_process_request_ring(adapter);
930
931 ll_adapter_reset(adapter);
932
933 /*
934 * Now process any completions. Note we do this AFTER adapter reset,
935 * which is strange, but stops races where completions get posted
936 * between processing the ring and issuing the reset. The backend will
937 * not touch the ring memory after reset, so the immediately pre-reset
938 * completion ring state is still valid.
939 */
940 pvscsi_process_completion_ring(adapter);
941
942 pvscsi_reset_all(adapter);
943 adapter->use_msg = use_msg;
944 pvscsi_setup_all_rings(adapter);
945 pvscsi_unmask_intr(adapter);
946
947 spin_unlock_irqrestore(&adapter->hw_lock, flags);
948
949 return SUCCESS;
950 }
951
pvscsi_bus_reset(struct scsi_cmnd * cmd)952 static int pvscsi_bus_reset(struct scsi_cmnd *cmd)
953 {
954 struct Scsi_Host *host = cmd->device->host;
955 struct pvscsi_adapter *adapter = shost_priv(host);
956 unsigned long flags;
957
958 scmd_printk(KERN_INFO, cmd, "SCSI Bus reset\n");
959
960 /*
961 * We don't want to queue new requests for this bus after
962 * flushing all pending requests to emulation, since new
963 * requests could then sneak in during this bus reset phase,
964 * so take the lock now.
965 */
966 spin_lock_irqsave(&adapter->hw_lock, flags);
967
968 pvscsi_process_request_ring(adapter);
969 ll_bus_reset(adapter);
970 pvscsi_process_completion_ring(adapter);
971
972 spin_unlock_irqrestore(&adapter->hw_lock, flags);
973
974 return SUCCESS;
975 }
976
pvscsi_device_reset(struct scsi_cmnd * cmd)977 static int pvscsi_device_reset(struct scsi_cmnd *cmd)
978 {
979 struct Scsi_Host *host = cmd->device->host;
980 struct pvscsi_adapter *adapter = shost_priv(host);
981 unsigned long flags;
982
983 scmd_printk(KERN_INFO, cmd, "SCSI device reset on scsi%u:%u\n",
984 host->host_no, cmd->device->id);
985
986 /*
987 * We don't want to queue new requests for this device after flushing
988 * all pending requests to emulation, since new requests could then
989 * sneak in during this device reset phase, so take the lock now.
990 */
991 spin_lock_irqsave(&adapter->hw_lock, flags);
992
993 pvscsi_process_request_ring(adapter);
994 ll_device_reset(adapter, cmd->device->id);
995 pvscsi_process_completion_ring(adapter);
996
997 spin_unlock_irqrestore(&adapter->hw_lock, flags);
998
999 return SUCCESS;
1000 }
1001
1002 static struct scsi_host_template pvscsi_template;
1003
pvscsi_info(struct Scsi_Host * host)1004 static const char *pvscsi_info(struct Scsi_Host *host)
1005 {
1006 struct pvscsi_adapter *adapter = shost_priv(host);
1007 static char buf[256];
1008
1009 sprintf(buf, "VMware PVSCSI storage adapter rev %d, req/cmp/msg rings: "
1010 "%u/%u/%u pages, cmd_per_lun=%u", adapter->rev,
1011 adapter->req_pages, adapter->cmp_pages, adapter->msg_pages,
1012 pvscsi_template.cmd_per_lun);
1013
1014 return buf;
1015 }
1016
1017 static struct scsi_host_template pvscsi_template = {
1018 .module = THIS_MODULE,
1019 .name = "VMware PVSCSI Host Adapter",
1020 .proc_name = "vmw_pvscsi",
1021 .info = pvscsi_info,
1022 .queuecommand = pvscsi_queue,
1023 .this_id = -1,
1024 .sg_tablesize = PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT,
1025 .dma_boundary = UINT_MAX,
1026 .max_sectors = 0xffff,
1027 .change_queue_depth = pvscsi_change_queue_depth,
1028 .eh_abort_handler = pvscsi_abort,
1029 .eh_device_reset_handler = pvscsi_device_reset,
1030 .eh_bus_reset_handler = pvscsi_bus_reset,
1031 .eh_host_reset_handler = pvscsi_host_reset,
1032 };
1033
pvscsi_process_msg(const struct pvscsi_adapter * adapter,const struct PVSCSIRingMsgDesc * e)1034 static void pvscsi_process_msg(const struct pvscsi_adapter *adapter,
1035 const struct PVSCSIRingMsgDesc *e)
1036 {
1037 struct PVSCSIRingsState *s = adapter->rings_state;
1038 struct Scsi_Host *host = adapter->host;
1039 struct scsi_device *sdev;
1040
1041 printk(KERN_INFO "vmw_pvscsi: msg type: 0x%x - MSG RING: %u/%u (%u) \n",
1042 e->type, s->msgProdIdx, s->msgConsIdx, s->msgNumEntriesLog2);
1043
1044 BUILD_BUG_ON(PVSCSI_MSG_LAST != 2);
1045
1046 if (e->type == PVSCSI_MSG_DEV_ADDED) {
1047 struct PVSCSIMsgDescDevStatusChanged *desc;
1048 desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
1049
1050 printk(KERN_INFO
1051 "vmw_pvscsi: msg: device added at scsi%u:%u:%u\n",
1052 desc->bus, desc->target, desc->lun[1]);
1053
1054 if (!scsi_host_get(host))
1055 return;
1056
1057 sdev = scsi_device_lookup(host, desc->bus, desc->target,
1058 desc->lun[1]);
1059 if (sdev) {
1060 printk(KERN_INFO "vmw_pvscsi: device already exists\n");
1061 scsi_device_put(sdev);
1062 } else
1063 scsi_add_device(adapter->host, desc->bus,
1064 desc->target, desc->lun[1]);
1065
1066 scsi_host_put(host);
1067 } else if (e->type == PVSCSI_MSG_DEV_REMOVED) {
1068 struct PVSCSIMsgDescDevStatusChanged *desc;
1069 desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
1070
1071 printk(KERN_INFO
1072 "vmw_pvscsi: msg: device removed at scsi%u:%u:%u\n",
1073 desc->bus, desc->target, desc->lun[1]);
1074
1075 if (!scsi_host_get(host))
1076 return;
1077
1078 sdev = scsi_device_lookup(host, desc->bus, desc->target,
1079 desc->lun[1]);
1080 if (sdev) {
1081 scsi_remove_device(sdev);
1082 scsi_device_put(sdev);
1083 } else
1084 printk(KERN_INFO
1085 "vmw_pvscsi: failed to lookup scsi%u:%u:%u\n",
1086 desc->bus, desc->target, desc->lun[1]);
1087
1088 scsi_host_put(host);
1089 }
1090 }
1091
pvscsi_msg_pending(const struct pvscsi_adapter * adapter)1092 static int pvscsi_msg_pending(const struct pvscsi_adapter *adapter)
1093 {
1094 struct PVSCSIRingsState *s = adapter->rings_state;
1095
1096 return s->msgProdIdx != s->msgConsIdx;
1097 }
1098
pvscsi_process_msg_ring(const struct pvscsi_adapter * adapter)1099 static void pvscsi_process_msg_ring(const struct pvscsi_adapter *adapter)
1100 {
1101 struct PVSCSIRingsState *s = adapter->rings_state;
1102 struct PVSCSIRingMsgDesc *ring = adapter->msg_ring;
1103 u32 msg_entries = s->msgNumEntriesLog2;
1104
1105 while (pvscsi_msg_pending(adapter)) {
1106 struct PVSCSIRingMsgDesc *e = ring + (s->msgConsIdx &
1107 MASK(msg_entries));
1108
1109 barrier();
1110 pvscsi_process_msg(adapter, e);
1111 barrier();
1112 s->msgConsIdx++;
1113 }
1114 }
1115
pvscsi_msg_workqueue_handler(struct work_struct * data)1116 static void pvscsi_msg_workqueue_handler(struct work_struct *data)
1117 {
1118 struct pvscsi_adapter *adapter;
1119
1120 adapter = container_of(data, struct pvscsi_adapter, work);
1121
1122 pvscsi_process_msg_ring(adapter);
1123 }
1124
pvscsi_setup_msg_workqueue(struct pvscsi_adapter * adapter)1125 static int pvscsi_setup_msg_workqueue(struct pvscsi_adapter *adapter)
1126 {
1127 char name[32];
1128
1129 if (!pvscsi_use_msg)
1130 return 0;
1131
1132 pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND,
1133 PVSCSI_CMD_SETUP_MSG_RING);
1134
1135 if (pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS) == -1)
1136 return 0;
1137
1138 snprintf(name, sizeof(name),
1139 "vmw_pvscsi_wq_%u", adapter->host->host_no);
1140
1141 adapter->workqueue = create_singlethread_workqueue(name);
1142 if (!adapter->workqueue) {
1143 printk(KERN_ERR "vmw_pvscsi: failed to create work queue\n");
1144 return 0;
1145 }
1146 INIT_WORK(&adapter->work, pvscsi_msg_workqueue_handler);
1147
1148 return 1;
1149 }
1150
pvscsi_setup_req_threshold(struct pvscsi_adapter * adapter,bool enable)1151 static bool pvscsi_setup_req_threshold(struct pvscsi_adapter *adapter,
1152 bool enable)
1153 {
1154 u32 val;
1155
1156 if (!pvscsi_use_req_threshold)
1157 return false;
1158
1159 pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND,
1160 PVSCSI_CMD_SETUP_REQCALLTHRESHOLD);
1161 val = pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS);
1162 if (val == -1) {
1163 printk(KERN_INFO "vmw_pvscsi: device does not support req_threshold\n");
1164 return false;
1165 } else {
1166 struct PVSCSICmdDescSetupReqCall cmd_msg = { 0 };
1167 cmd_msg.enable = enable;
1168 printk(KERN_INFO
1169 "vmw_pvscsi: %sabling reqCallThreshold\n",
1170 enable ? "en" : "dis");
1171 pvscsi_write_cmd_desc(adapter,
1172 PVSCSI_CMD_SETUP_REQCALLTHRESHOLD,
1173 &cmd_msg, sizeof(cmd_msg));
1174 return pvscsi_reg_read(adapter,
1175 PVSCSI_REG_OFFSET_COMMAND_STATUS) != 0;
1176 }
1177 }
1178
pvscsi_isr(int irq,void * devp)1179 static irqreturn_t pvscsi_isr(int irq, void *devp)
1180 {
1181 struct pvscsi_adapter *adapter = devp;
1182 unsigned long flags;
1183
1184 spin_lock_irqsave(&adapter->hw_lock, flags);
1185 pvscsi_process_completion_ring(adapter);
1186 if (adapter->use_msg && pvscsi_msg_pending(adapter))
1187 queue_work(adapter->workqueue, &adapter->work);
1188 spin_unlock_irqrestore(&adapter->hw_lock, flags);
1189
1190 return IRQ_HANDLED;
1191 }
1192
pvscsi_shared_isr(int irq,void * devp)1193 static irqreturn_t pvscsi_shared_isr(int irq, void *devp)
1194 {
1195 struct pvscsi_adapter *adapter = devp;
1196 u32 val = pvscsi_read_intr_status(adapter);
1197
1198 if (!(val & PVSCSI_INTR_ALL_SUPPORTED))
1199 return IRQ_NONE;
1200 pvscsi_write_intr_status(devp, val);
1201 return pvscsi_isr(irq, devp);
1202 }
1203
pvscsi_free_sgls(const struct pvscsi_adapter * adapter)1204 static void pvscsi_free_sgls(const struct pvscsi_adapter *adapter)
1205 {
1206 struct pvscsi_ctx *ctx = adapter->cmd_map;
1207 unsigned i;
1208
1209 for (i = 0; i < adapter->req_depth; ++i, ++ctx)
1210 free_pages((unsigned long)ctx->sgl, get_order(SGL_SIZE));
1211 }
1212
pvscsi_shutdown_intr(struct pvscsi_adapter * adapter)1213 static void pvscsi_shutdown_intr(struct pvscsi_adapter *adapter)
1214 {
1215 free_irq(pci_irq_vector(adapter->dev, 0), adapter);
1216 pci_free_irq_vectors(adapter->dev);
1217 }
1218
pvscsi_release_resources(struct pvscsi_adapter * adapter)1219 static void pvscsi_release_resources(struct pvscsi_adapter *adapter)
1220 {
1221 if (adapter->workqueue)
1222 destroy_workqueue(adapter->workqueue);
1223
1224 if (adapter->mmioBase)
1225 pci_iounmap(adapter->dev, adapter->mmioBase);
1226
1227 pci_release_regions(adapter->dev);
1228
1229 if (adapter->cmd_map) {
1230 pvscsi_free_sgls(adapter);
1231 kfree(adapter->cmd_map);
1232 }
1233
1234 if (adapter->rings_state)
1235 dma_free_coherent(&adapter->dev->dev, PAGE_SIZE,
1236 adapter->rings_state, adapter->ringStatePA);
1237
1238 if (adapter->req_ring)
1239 dma_free_coherent(&adapter->dev->dev,
1240 adapter->req_pages * PAGE_SIZE,
1241 adapter->req_ring, adapter->reqRingPA);
1242
1243 if (adapter->cmp_ring)
1244 dma_free_coherent(&adapter->dev->dev,
1245 adapter->cmp_pages * PAGE_SIZE,
1246 adapter->cmp_ring, adapter->cmpRingPA);
1247
1248 if (adapter->msg_ring)
1249 dma_free_coherent(&adapter->dev->dev,
1250 adapter->msg_pages * PAGE_SIZE,
1251 adapter->msg_ring, adapter->msgRingPA);
1252 }
1253
1254 /*
1255 * Allocate scatter gather lists.
1256 *
1257 * These are statically allocated. Trying to be clever was not worth it.
1258 *
1259 * Dynamic allocation can fail, and we can't go deep into the memory
1260 * allocator, since we're a SCSI driver, and trying too hard to allocate
1261 * memory might generate disk I/O. We also don't want to fail disk I/O
1262 * in that case because we can't get an allocation - the I/O could be
1263 * trying to swap out data to free memory. Since that is pathological,
1264 * just use a statically allocated scatter list.
1265 *
1266 */
pvscsi_allocate_sg(struct pvscsi_adapter * adapter)1267 static int pvscsi_allocate_sg(struct pvscsi_adapter *adapter)
1268 {
1269 struct pvscsi_ctx *ctx;
1270 int i;
1271
1272 ctx = adapter->cmd_map;
1273 BUILD_BUG_ON(sizeof(struct pvscsi_sg_list) > SGL_SIZE);
1274
1275 for (i = 0; i < adapter->req_depth; ++i, ++ctx) {
1276 ctx->sgl = (void *)__get_free_pages(GFP_KERNEL,
1277 get_order(SGL_SIZE));
1278 ctx->sglPA = 0;
1279 BUG_ON(!IS_ALIGNED(((unsigned long)ctx->sgl), PAGE_SIZE));
1280 if (!ctx->sgl) {
1281 for (; i >= 0; --i, --ctx) {
1282 free_pages((unsigned long)ctx->sgl,
1283 get_order(SGL_SIZE));
1284 ctx->sgl = NULL;
1285 }
1286 return -ENOMEM;
1287 }
1288 }
1289
1290 return 0;
1291 }
1292
1293 /*
1294 * Query the device, fetch the config info and return the
1295 * maximum number of targets on the adapter. In case of
1296 * failure due to any reason return default i.e. 16.
1297 */
pvscsi_get_max_targets(struct pvscsi_adapter * adapter)1298 static u32 pvscsi_get_max_targets(struct pvscsi_adapter *adapter)
1299 {
1300 struct PVSCSICmdDescConfigCmd cmd;
1301 struct PVSCSIConfigPageHeader *header;
1302 struct device *dev;
1303 dma_addr_t configPagePA;
1304 void *config_page;
1305 u32 numPhys = 16;
1306
1307 dev = pvscsi_dev(adapter);
1308 config_page = dma_alloc_coherent(&adapter->dev->dev, PAGE_SIZE,
1309 &configPagePA, GFP_KERNEL);
1310 if (!config_page) {
1311 dev_warn(dev, "vmw_pvscsi: failed to allocate memory for config page\n");
1312 goto exit;
1313 }
1314 BUG_ON(configPagePA & ~PAGE_MASK);
1315
1316 /* Fetch config info from the device. */
1317 cmd.configPageAddress = ((u64)PVSCSI_CONFIG_CONTROLLER_ADDRESS) << 32;
1318 cmd.configPageNum = PVSCSI_CONFIG_PAGE_CONTROLLER;
1319 cmd.cmpAddr = configPagePA;
1320 cmd._pad = 0;
1321
1322 /*
1323 * Mark the completion page header with error values. If the device
1324 * completes the command successfully, it sets the status values to
1325 * indicate success.
1326 */
1327 header = config_page;
1328 memset(header, 0, sizeof *header);
1329 header->hostStatus = BTSTAT_INVPARAM;
1330 header->scsiStatus = SDSTAT_CHECK;
1331
1332 pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_CONFIG, &cmd, sizeof cmd);
1333
1334 if (header->hostStatus == BTSTAT_SUCCESS &&
1335 header->scsiStatus == SDSTAT_GOOD) {
1336 struct PVSCSIConfigPageController *config;
1337
1338 config = config_page;
1339 numPhys = config->numPhys;
1340 } else
1341 dev_warn(dev, "vmw_pvscsi: PVSCSI_CMD_CONFIG failed. hostStatus = 0x%x, scsiStatus = 0x%x\n",
1342 header->hostStatus, header->scsiStatus);
1343 dma_free_coherent(&adapter->dev->dev, PAGE_SIZE, config_page,
1344 configPagePA);
1345 exit:
1346 return numPhys;
1347 }
1348
pvscsi_probe(struct pci_dev * pdev,const struct pci_device_id * id)1349 static int pvscsi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1350 {
1351 unsigned int irq_flag = PCI_IRQ_MSIX | PCI_IRQ_MSI | PCI_IRQ_LEGACY;
1352 struct pvscsi_adapter *adapter;
1353 struct pvscsi_adapter adapter_temp;
1354 struct Scsi_Host *host = NULL;
1355 unsigned int i;
1356 int error;
1357 u32 max_id;
1358
1359 error = -ENODEV;
1360
1361 if (pci_enable_device(pdev))
1362 return error;
1363
1364 if (!dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64))) {
1365 printk(KERN_INFO "vmw_pvscsi: using 64bit dma\n");
1366 } else if (!dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32))) {
1367 printk(KERN_INFO "vmw_pvscsi: using 32bit dma\n");
1368 } else {
1369 printk(KERN_ERR "vmw_pvscsi: failed to set DMA mask\n");
1370 goto out_disable_device;
1371 }
1372
1373 /*
1374 * Let's use a temp pvscsi_adapter struct until we find the number of
1375 * targets on the adapter, after that we will switch to the real
1376 * allocated struct.
1377 */
1378 adapter = &adapter_temp;
1379 memset(adapter, 0, sizeof(*adapter));
1380 adapter->dev = pdev;
1381 adapter->rev = pdev->revision;
1382
1383 if (pci_request_regions(pdev, "vmw_pvscsi")) {
1384 printk(KERN_ERR "vmw_pvscsi: pci memory selection failed\n");
1385 goto out_disable_device;
1386 }
1387
1388 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
1389 if ((pci_resource_flags(pdev, i) & PCI_BASE_ADDRESS_SPACE_IO))
1390 continue;
1391
1392 if (pci_resource_len(pdev, i) < PVSCSI_MEM_SPACE_SIZE)
1393 continue;
1394
1395 break;
1396 }
1397
1398 if (i == DEVICE_COUNT_RESOURCE) {
1399 printk(KERN_ERR
1400 "vmw_pvscsi: adapter has no suitable MMIO region\n");
1401 goto out_release_resources_and_disable;
1402 }
1403
1404 adapter->mmioBase = pci_iomap(pdev, i, PVSCSI_MEM_SPACE_SIZE);
1405
1406 if (!adapter->mmioBase) {
1407 printk(KERN_ERR
1408 "vmw_pvscsi: can't iomap for BAR %d memsize %lu\n",
1409 i, PVSCSI_MEM_SPACE_SIZE);
1410 goto out_release_resources_and_disable;
1411 }
1412
1413 pci_set_master(pdev);
1414
1415 /*
1416 * Ask the device for max number of targets before deciding the
1417 * default pvscsi_ring_pages value.
1418 */
1419 max_id = pvscsi_get_max_targets(adapter);
1420 printk(KERN_INFO "vmw_pvscsi: max_id: %u\n", max_id);
1421
1422 if (pvscsi_ring_pages == 0)
1423 /*
1424 * Set the right default value. Up to 16 it is 8, above it is
1425 * max.
1426 */
1427 pvscsi_ring_pages = (max_id > 16) ?
1428 PVSCSI_SETUP_RINGS_MAX_NUM_PAGES :
1429 PVSCSI_DEFAULT_NUM_PAGES_PER_RING;
1430 printk(KERN_INFO
1431 "vmw_pvscsi: setting ring_pages to %d\n",
1432 pvscsi_ring_pages);
1433
1434 pvscsi_template.can_queue =
1435 min(PVSCSI_MAX_NUM_PAGES_REQ_RING, pvscsi_ring_pages) *
1436 PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
1437 pvscsi_template.cmd_per_lun =
1438 min(pvscsi_template.can_queue, pvscsi_cmd_per_lun);
1439 host = scsi_host_alloc(&pvscsi_template, sizeof(struct pvscsi_adapter));
1440 if (!host) {
1441 printk(KERN_ERR "vmw_pvscsi: failed to allocate host\n");
1442 goto out_release_resources_and_disable;
1443 }
1444
1445 /*
1446 * Let's use the real pvscsi_adapter struct here onwards.
1447 */
1448 adapter = shost_priv(host);
1449 memset(adapter, 0, sizeof(*adapter));
1450 adapter->dev = pdev;
1451 adapter->host = host;
1452 /*
1453 * Copy back what we already have to the allocated adapter struct.
1454 */
1455 adapter->rev = adapter_temp.rev;
1456 adapter->mmioBase = adapter_temp.mmioBase;
1457
1458 spin_lock_init(&adapter->hw_lock);
1459 host->max_channel = 0;
1460 host->max_lun = 1;
1461 host->max_cmd_len = 16;
1462 host->max_id = max_id;
1463
1464 pci_set_drvdata(pdev, host);
1465
1466 ll_adapter_reset(adapter);
1467
1468 adapter->use_msg = pvscsi_setup_msg_workqueue(adapter);
1469
1470 error = pvscsi_allocate_rings(adapter);
1471 if (error) {
1472 printk(KERN_ERR "vmw_pvscsi: unable to allocate ring memory\n");
1473 goto out_release_resources;
1474 }
1475
1476 /*
1477 * From this point on we should reset the adapter if anything goes
1478 * wrong.
1479 */
1480 pvscsi_setup_all_rings(adapter);
1481
1482 adapter->cmd_map = kcalloc(adapter->req_depth,
1483 sizeof(struct pvscsi_ctx), GFP_KERNEL);
1484 if (!adapter->cmd_map) {
1485 printk(KERN_ERR "vmw_pvscsi: failed to allocate memory.\n");
1486 error = -ENOMEM;
1487 goto out_reset_adapter;
1488 }
1489
1490 INIT_LIST_HEAD(&adapter->cmd_pool);
1491 for (i = 0; i < adapter->req_depth; i++) {
1492 struct pvscsi_ctx *ctx = adapter->cmd_map + i;
1493 list_add(&ctx->list, &adapter->cmd_pool);
1494 }
1495
1496 error = pvscsi_allocate_sg(adapter);
1497 if (error) {
1498 printk(KERN_ERR "vmw_pvscsi: unable to allocate s/g table\n");
1499 goto out_reset_adapter;
1500 }
1501
1502 if (pvscsi_disable_msix)
1503 irq_flag &= ~PCI_IRQ_MSIX;
1504 if (pvscsi_disable_msi)
1505 irq_flag &= ~PCI_IRQ_MSI;
1506
1507 error = pci_alloc_irq_vectors(adapter->dev, 1, 1, irq_flag);
1508 if (error < 0)
1509 goto out_reset_adapter;
1510
1511 adapter->use_req_threshold = pvscsi_setup_req_threshold(adapter, true);
1512 printk(KERN_DEBUG "vmw_pvscsi: driver-based request coalescing %sabled\n",
1513 adapter->use_req_threshold ? "en" : "dis");
1514
1515 if (adapter->dev->msix_enabled || adapter->dev->msi_enabled) {
1516 printk(KERN_INFO "vmw_pvscsi: using MSI%s\n",
1517 adapter->dev->msix_enabled ? "-X" : "");
1518 error = request_irq(pci_irq_vector(pdev, 0), pvscsi_isr,
1519 0, "vmw_pvscsi", adapter);
1520 } else {
1521 printk(KERN_INFO "vmw_pvscsi: using INTx\n");
1522 error = request_irq(pci_irq_vector(pdev, 0), pvscsi_shared_isr,
1523 IRQF_SHARED, "vmw_pvscsi", adapter);
1524 }
1525
1526 if (error) {
1527 printk(KERN_ERR
1528 "vmw_pvscsi: unable to request IRQ: %d\n", error);
1529 goto out_reset_adapter;
1530 }
1531
1532 error = scsi_add_host(host, &pdev->dev);
1533 if (error) {
1534 printk(KERN_ERR
1535 "vmw_pvscsi: scsi_add_host failed: %d\n", error);
1536 goto out_reset_adapter;
1537 }
1538
1539 dev_info(&pdev->dev, "VMware PVSCSI rev %d host #%u\n",
1540 adapter->rev, host->host_no);
1541
1542 pvscsi_unmask_intr(adapter);
1543
1544 scsi_scan_host(host);
1545
1546 return 0;
1547
1548 out_reset_adapter:
1549 ll_adapter_reset(adapter);
1550 out_release_resources:
1551 pvscsi_shutdown_intr(adapter);
1552 pvscsi_release_resources(adapter);
1553 scsi_host_put(host);
1554 out_disable_device:
1555 pci_disable_device(pdev);
1556
1557 return error;
1558
1559 out_release_resources_and_disable:
1560 pvscsi_shutdown_intr(adapter);
1561 pvscsi_release_resources(adapter);
1562 goto out_disable_device;
1563 }
1564
__pvscsi_shutdown(struct pvscsi_adapter * adapter)1565 static void __pvscsi_shutdown(struct pvscsi_adapter *adapter)
1566 {
1567 pvscsi_mask_intr(adapter);
1568
1569 if (adapter->workqueue)
1570 flush_workqueue(adapter->workqueue);
1571
1572 pvscsi_shutdown_intr(adapter);
1573
1574 pvscsi_process_request_ring(adapter);
1575 pvscsi_process_completion_ring(adapter);
1576 ll_adapter_reset(adapter);
1577 }
1578
pvscsi_shutdown(struct pci_dev * dev)1579 static void pvscsi_shutdown(struct pci_dev *dev)
1580 {
1581 struct Scsi_Host *host = pci_get_drvdata(dev);
1582 struct pvscsi_adapter *adapter = shost_priv(host);
1583
1584 __pvscsi_shutdown(adapter);
1585 }
1586
pvscsi_remove(struct pci_dev * pdev)1587 static void pvscsi_remove(struct pci_dev *pdev)
1588 {
1589 struct Scsi_Host *host = pci_get_drvdata(pdev);
1590 struct pvscsi_adapter *adapter = shost_priv(host);
1591
1592 scsi_remove_host(host);
1593
1594 __pvscsi_shutdown(adapter);
1595 pvscsi_release_resources(adapter);
1596
1597 scsi_host_put(host);
1598
1599 pci_disable_device(pdev);
1600 }
1601
1602 static struct pci_driver pvscsi_pci_driver = {
1603 .name = "vmw_pvscsi",
1604 .id_table = pvscsi_pci_tbl,
1605 .probe = pvscsi_probe,
1606 .remove = pvscsi_remove,
1607 .shutdown = pvscsi_shutdown,
1608 };
1609
pvscsi_init(void)1610 static int __init pvscsi_init(void)
1611 {
1612 pr_info("%s - version %s\n",
1613 PVSCSI_LINUX_DRIVER_DESC, PVSCSI_DRIVER_VERSION_STRING);
1614 return pci_register_driver(&pvscsi_pci_driver);
1615 }
1616
pvscsi_exit(void)1617 static void __exit pvscsi_exit(void)
1618 {
1619 pci_unregister_driver(&pvscsi_pci_driver);
1620 }
1621
1622 module_init(pvscsi_init);
1623 module_exit(pvscsi_exit);
1624