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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  * Maintained by: Jim Gill <jgill@vmware.com>
21  *
22  */
23 
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/interrupt.h>
27 #include <linux/slab.h>
28 #include <linux/workqueue.h>
29 #include <linux/pci.h>
30 
31 #include <scsi/scsi.h>
32 #include <scsi/scsi_host.h>
33 #include <scsi/scsi_cmnd.h>
34 #include <scsi/scsi_device.h>
35 #include <scsi/scsi_tcq.h>
36 
37 #include "vmw_pvscsi.h"
38 
39 #define PVSCSI_LINUX_DRIVER_DESC "VMware PVSCSI driver"
40 
41 MODULE_DESCRIPTION(PVSCSI_LINUX_DRIVER_DESC);
42 MODULE_AUTHOR("VMware, Inc.");
43 MODULE_LICENSE("GPL");
44 MODULE_VERSION(PVSCSI_DRIVER_VERSION_STRING);
45 
46 #define PVSCSI_DEFAULT_NUM_PAGES_PER_RING	8
47 #define PVSCSI_DEFAULT_NUM_PAGES_MSG_RING	1
48 #define PVSCSI_DEFAULT_QUEUE_DEPTH		254
49 #define SGL_SIZE				PAGE_SIZE
50 
51 struct pvscsi_sg_list {
52 	struct PVSCSISGElement sge[PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT];
53 };
54 
55 struct pvscsi_ctx {
56 	/*
57 	 * The index of the context in cmd_map serves as the context ID for a
58 	 * 1-to-1 mapping completions back to requests.
59 	 */
60 	struct scsi_cmnd	*cmd;
61 	struct pvscsi_sg_list	*sgl;
62 	struct list_head	list;
63 	dma_addr_t		dataPA;
64 	dma_addr_t		sensePA;
65 	dma_addr_t		sglPA;
66 	struct completion	*abort_cmp;
67 };
68 
69 struct pvscsi_adapter {
70 	char				*mmioBase;
71 	u8				rev;
72 	bool				use_msg;
73 	bool				use_req_threshold;
74 
75 	spinlock_t			hw_lock;
76 
77 	struct workqueue_struct		*workqueue;
78 	struct work_struct		work;
79 
80 	struct PVSCSIRingReqDesc	*req_ring;
81 	unsigned			req_pages;
82 	unsigned			req_depth;
83 	dma_addr_t			reqRingPA;
84 
85 	struct PVSCSIRingCmpDesc	*cmp_ring;
86 	unsigned			cmp_pages;
87 	dma_addr_t			cmpRingPA;
88 
89 	struct PVSCSIRingMsgDesc	*msg_ring;
90 	unsigned			msg_pages;
91 	dma_addr_t			msgRingPA;
92 
93 	struct PVSCSIRingsState		*rings_state;
94 	dma_addr_t			ringStatePA;
95 
96 	struct pci_dev			*dev;
97 	struct Scsi_Host		*host;
98 
99 	struct list_head		cmd_pool;
100 	struct pvscsi_ctx		*cmd_map;
101 };
102 
103 
104 /* Command line parameters */
105 static int pvscsi_ring_pages;
106 static int pvscsi_msg_ring_pages = PVSCSI_DEFAULT_NUM_PAGES_MSG_RING;
107 static int pvscsi_cmd_per_lun    = PVSCSI_DEFAULT_QUEUE_DEPTH;
108 static bool pvscsi_disable_msi;
109 static bool pvscsi_disable_msix;
110 static bool pvscsi_use_msg       = true;
111 static bool pvscsi_use_req_threshold = true;
112 
113 #define PVSCSI_RW (S_IRUSR | S_IWUSR)
114 
115 module_param_named(ring_pages, pvscsi_ring_pages, int, PVSCSI_RW);
116 MODULE_PARM_DESC(ring_pages, "Number of pages per req/cmp ring - (default="
117 		 __stringify(PVSCSI_DEFAULT_NUM_PAGES_PER_RING)
118 		 "[up to 16 targets],"
119 		 __stringify(PVSCSI_SETUP_RINGS_MAX_NUM_PAGES)
120 		 "[for 16+ targets])");
121 
122 module_param_named(msg_ring_pages, pvscsi_msg_ring_pages, int, PVSCSI_RW);
123 MODULE_PARM_DESC(msg_ring_pages, "Number of pages for the msg ring - (default="
124 		 __stringify(PVSCSI_DEFAULT_NUM_PAGES_MSG_RING) ")");
125 
126 module_param_named(cmd_per_lun, pvscsi_cmd_per_lun, int, PVSCSI_RW);
127 MODULE_PARM_DESC(cmd_per_lun, "Maximum commands per lun - (default="
128 		 __stringify(PVSCSI_DEFAULT_QUEUE_DEPTH) ")");
129 
130 module_param_named(disable_msi, pvscsi_disable_msi, bool, PVSCSI_RW);
131 MODULE_PARM_DESC(disable_msi, "Disable MSI use in driver - (default=0)");
132 
133 module_param_named(disable_msix, pvscsi_disable_msix, bool, PVSCSI_RW);
134 MODULE_PARM_DESC(disable_msix, "Disable MSI-X use in driver - (default=0)");
135 
136 module_param_named(use_msg, pvscsi_use_msg, bool, PVSCSI_RW);
137 MODULE_PARM_DESC(use_msg, "Use msg ring when available - (default=1)");
138 
139 module_param_named(use_req_threshold, pvscsi_use_req_threshold,
140 		   bool, PVSCSI_RW);
141 MODULE_PARM_DESC(use_req_threshold, "Use driver-based request coalescing if configured - (default=1)");
142 
143 static const struct pci_device_id pvscsi_pci_tbl[] = {
144 	{ PCI_VDEVICE(VMWARE, PCI_DEVICE_ID_VMWARE_PVSCSI) },
145 	{ 0 }
146 };
147 
148 MODULE_DEVICE_TABLE(pci, pvscsi_pci_tbl);
149 
150 static struct device *
pvscsi_dev(const struct pvscsi_adapter * adapter)151 pvscsi_dev(const struct pvscsi_adapter *adapter)
152 {
153 	return &(adapter->dev->dev);
154 }
155 
156 static struct pvscsi_ctx *
pvscsi_find_context(const struct pvscsi_adapter * adapter,struct scsi_cmnd * cmd)157 pvscsi_find_context(const struct pvscsi_adapter *adapter, struct scsi_cmnd *cmd)
158 {
159 	struct pvscsi_ctx *ctx, *end;
160 
161 	end = &adapter->cmd_map[adapter->req_depth];
162 	for (ctx = adapter->cmd_map; ctx < end; ctx++)
163 		if (ctx->cmd == cmd)
164 			return ctx;
165 
166 	return NULL;
167 }
168 
169 static struct pvscsi_ctx *
pvscsi_acquire_context(struct pvscsi_adapter * adapter,struct scsi_cmnd * cmd)170 pvscsi_acquire_context(struct pvscsi_adapter *adapter, struct scsi_cmnd *cmd)
171 {
172 	struct pvscsi_ctx *ctx;
173 
174 	if (list_empty(&adapter->cmd_pool))
175 		return NULL;
176 
177 	ctx = list_first_entry(&adapter->cmd_pool, struct pvscsi_ctx, list);
178 	ctx->cmd = cmd;
179 	list_del(&ctx->list);
180 
181 	return ctx;
182 }
183 
pvscsi_release_context(struct pvscsi_adapter * adapter,struct pvscsi_ctx * ctx)184 static void pvscsi_release_context(struct pvscsi_adapter *adapter,
185 				   struct pvscsi_ctx *ctx)
186 {
187 	ctx->cmd = NULL;
188 	ctx->abort_cmp = NULL;
189 	list_add(&ctx->list, &adapter->cmd_pool);
190 }
191 
192 /*
193  * Map a pvscsi_ctx struct to a context ID field value; we map to a simple
194  * non-zero integer. ctx always points to an entry in cmd_map array, hence
195  * the return value is always >=1.
196  */
pvscsi_map_context(const struct pvscsi_adapter * adapter,const struct pvscsi_ctx * ctx)197 static u64 pvscsi_map_context(const struct pvscsi_adapter *adapter,
198 			      const struct pvscsi_ctx *ctx)
199 {
200 	return ctx - adapter->cmd_map + 1;
201 }
202 
203 static struct pvscsi_ctx *
pvscsi_get_context(const struct pvscsi_adapter * adapter,u64 context)204 pvscsi_get_context(const struct pvscsi_adapter *adapter, u64 context)
205 {
206 	return &adapter->cmd_map[context - 1];
207 }
208 
pvscsi_reg_write(const struct pvscsi_adapter * adapter,u32 offset,u32 val)209 static void pvscsi_reg_write(const struct pvscsi_adapter *adapter,
210 			     u32 offset, u32 val)
211 {
212 	writel(val, adapter->mmioBase + offset);
213 }
214 
pvscsi_reg_read(const struct pvscsi_adapter * adapter,u32 offset)215 static u32 pvscsi_reg_read(const struct pvscsi_adapter *adapter, u32 offset)
216 {
217 	return readl(adapter->mmioBase + offset);
218 }
219 
pvscsi_read_intr_status(const struct pvscsi_adapter * adapter)220 static u32 pvscsi_read_intr_status(const struct pvscsi_adapter *adapter)
221 {
222 	return pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_INTR_STATUS);
223 }
224 
pvscsi_write_intr_status(const struct pvscsi_adapter * adapter,u32 val)225 static void pvscsi_write_intr_status(const struct pvscsi_adapter *adapter,
226 				     u32 val)
227 {
228 	pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_STATUS, val);
229 }
230 
pvscsi_unmask_intr(const struct pvscsi_adapter * adapter)231 static void pvscsi_unmask_intr(const struct pvscsi_adapter *adapter)
232 {
233 	u32 intr_bits;
234 
235 	intr_bits = PVSCSI_INTR_CMPL_MASK;
236 	if (adapter->use_msg)
237 		intr_bits |= PVSCSI_INTR_MSG_MASK;
238 
239 	pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_MASK, intr_bits);
240 }
241 
pvscsi_mask_intr(const struct pvscsi_adapter * adapter)242 static void pvscsi_mask_intr(const struct pvscsi_adapter *adapter)
243 {
244 	pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_MASK, 0);
245 }
246 
pvscsi_write_cmd_desc(const struct pvscsi_adapter * adapter,u32 cmd,const void * desc,size_t len)247 static void pvscsi_write_cmd_desc(const struct pvscsi_adapter *adapter,
248 				  u32 cmd, const void *desc, size_t len)
249 {
250 	const u32 *ptr = desc;
251 	size_t i;
252 
253 	len /= sizeof(*ptr);
254 	pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND, cmd);
255 	for (i = 0; i < len; i++)
256 		pvscsi_reg_write(adapter,
257 				 PVSCSI_REG_OFFSET_COMMAND_DATA, ptr[i]);
258 }
259 
pvscsi_abort_cmd(const struct pvscsi_adapter * adapter,const struct pvscsi_ctx * ctx)260 static void pvscsi_abort_cmd(const struct pvscsi_adapter *adapter,
261 			     const struct pvscsi_ctx *ctx)
262 {
263 	struct PVSCSICmdDescAbortCmd cmd = { 0 };
264 
265 	cmd.target = ctx->cmd->device->id;
266 	cmd.context = pvscsi_map_context(adapter, ctx);
267 
268 	pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_ABORT_CMD, &cmd, sizeof(cmd));
269 }
270 
pvscsi_kick_rw_io(const struct pvscsi_adapter * adapter)271 static void pvscsi_kick_rw_io(const struct pvscsi_adapter *adapter)
272 {
273 	pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_KICK_RW_IO, 0);
274 }
275 
pvscsi_process_request_ring(const struct pvscsi_adapter * adapter)276 static void pvscsi_process_request_ring(const struct pvscsi_adapter *adapter)
277 {
278 	pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_KICK_NON_RW_IO, 0);
279 }
280 
scsi_is_rw(unsigned char op)281 static int scsi_is_rw(unsigned char op)
282 {
283 	return op == READ_6  || op == WRITE_6 ||
284 	       op == READ_10 || op == WRITE_10 ||
285 	       op == READ_12 || op == WRITE_12 ||
286 	       op == READ_16 || op == WRITE_16;
287 }
288 
pvscsi_kick_io(const struct pvscsi_adapter * adapter,unsigned char op)289 static void pvscsi_kick_io(const struct pvscsi_adapter *adapter,
290 			   unsigned char op)
291 {
292 	if (scsi_is_rw(op)) {
293 		struct PVSCSIRingsState *s = adapter->rings_state;
294 
295 		if (!adapter->use_req_threshold ||
296 		    s->reqProdIdx - s->reqConsIdx >= s->reqCallThreshold)
297 			pvscsi_kick_rw_io(adapter);
298 	} else {
299 		pvscsi_process_request_ring(adapter);
300 	}
301 }
302 
ll_adapter_reset(const struct pvscsi_adapter * adapter)303 static void ll_adapter_reset(const struct pvscsi_adapter *adapter)
304 {
305 	dev_dbg(pvscsi_dev(adapter), "Adapter Reset on %p\n", adapter);
306 
307 	pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_ADAPTER_RESET, NULL, 0);
308 }
309 
ll_bus_reset(const struct pvscsi_adapter * adapter)310 static void ll_bus_reset(const struct pvscsi_adapter *adapter)
311 {
312 	dev_dbg(pvscsi_dev(adapter), "Resetting bus on %p\n", adapter);
313 
314 	pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_RESET_BUS, NULL, 0);
315 }
316 
ll_device_reset(const struct pvscsi_adapter * adapter,u32 target)317 static void ll_device_reset(const struct pvscsi_adapter *adapter, u32 target)
318 {
319 	struct PVSCSICmdDescResetDevice cmd = { 0 };
320 
321 	dev_dbg(pvscsi_dev(adapter), "Resetting device: target=%u\n", target);
322 
323 	cmd.target = target;
324 
325 	pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_RESET_DEVICE,
326 			      &cmd, sizeof(cmd));
327 }
328 
pvscsi_create_sg(struct pvscsi_ctx * ctx,struct scatterlist * sg,unsigned count)329 static void pvscsi_create_sg(struct pvscsi_ctx *ctx,
330 			     struct scatterlist *sg, unsigned count)
331 {
332 	unsigned i;
333 	struct PVSCSISGElement *sge;
334 
335 	BUG_ON(count > PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT);
336 
337 	sge = &ctx->sgl->sge[0];
338 	for (i = 0; i < count; i++, sg = sg_next(sg)) {
339 		sge[i].addr   = sg_dma_address(sg);
340 		sge[i].length = sg_dma_len(sg);
341 		sge[i].flags  = 0;
342 	}
343 }
344 
345 /*
346  * Map all data buffers for a command into PCI space and
347  * setup the scatter/gather list if needed.
348  */
pvscsi_map_buffers(struct pvscsi_adapter * adapter,struct pvscsi_ctx * ctx,struct scsi_cmnd * cmd,struct PVSCSIRingReqDesc * e)349 static int pvscsi_map_buffers(struct pvscsi_adapter *adapter,
350 			      struct pvscsi_ctx *ctx, struct scsi_cmnd *cmd,
351 			      struct PVSCSIRingReqDesc *e)
352 {
353 	unsigned count;
354 	unsigned bufflen = scsi_bufflen(cmd);
355 	struct scatterlist *sg;
356 
357 	e->dataLen = bufflen;
358 	e->dataAddr = 0;
359 	if (bufflen == 0)
360 		return 0;
361 
362 	sg = scsi_sglist(cmd);
363 	count = scsi_sg_count(cmd);
364 	if (count != 0) {
365 		int segs = scsi_dma_map(cmd);
366 
367 		if (segs == -ENOMEM) {
368 			scmd_printk(KERN_DEBUG, cmd,
369 				    "vmw_pvscsi: Failed to map cmd sglist for DMA.\n");
370 			return -ENOMEM;
371 		} else if (segs > 1) {
372 			pvscsi_create_sg(ctx, sg, segs);
373 
374 			e->flags |= PVSCSI_FLAG_CMD_WITH_SG_LIST;
375 			ctx->sglPA = dma_map_single(&adapter->dev->dev,
376 					ctx->sgl, SGL_SIZE, DMA_TO_DEVICE);
377 			if (dma_mapping_error(&adapter->dev->dev, ctx->sglPA)) {
378 				scmd_printk(KERN_ERR, cmd,
379 					    "vmw_pvscsi: Failed to map ctx sglist for DMA.\n");
380 				scsi_dma_unmap(cmd);
381 				ctx->sglPA = 0;
382 				return -ENOMEM;
383 			}
384 			e->dataAddr = ctx->sglPA;
385 		} else
386 			e->dataAddr = sg_dma_address(sg);
387 	} else {
388 		/*
389 		 * In case there is no S/G list, scsi_sglist points
390 		 * directly to the buffer.
391 		 */
392 		ctx->dataPA = dma_map_single(&adapter->dev->dev, sg, bufflen,
393 					     cmd->sc_data_direction);
394 		if (dma_mapping_error(&adapter->dev->dev, ctx->dataPA)) {
395 			scmd_printk(KERN_DEBUG, cmd,
396 				    "vmw_pvscsi: Failed to map direct data buffer for DMA.\n");
397 			return -ENOMEM;
398 		}
399 		e->dataAddr = ctx->dataPA;
400 	}
401 
402 	return 0;
403 }
404 
405 /*
406  * The device incorrectly doesn't clear the first byte of the sense
407  * buffer in some cases. We have to do it ourselves.
408  * Otherwise we run into trouble when SWIOTLB is forced.
409  */
pvscsi_patch_sense(struct scsi_cmnd * cmd)410 static void pvscsi_patch_sense(struct scsi_cmnd *cmd)
411 {
412 	if (cmd->sense_buffer)
413 		cmd->sense_buffer[0] = 0;
414 }
415 
pvscsi_unmap_buffers(const struct pvscsi_adapter * adapter,struct pvscsi_ctx * ctx)416 static void pvscsi_unmap_buffers(const struct pvscsi_adapter *adapter,
417 				 struct pvscsi_ctx *ctx)
418 {
419 	struct scsi_cmnd *cmd;
420 	unsigned bufflen;
421 
422 	cmd = ctx->cmd;
423 	bufflen = scsi_bufflen(cmd);
424 
425 	if (bufflen != 0) {
426 		unsigned count = scsi_sg_count(cmd);
427 
428 		if (count != 0) {
429 			scsi_dma_unmap(cmd);
430 			if (ctx->sglPA) {
431 				dma_unmap_single(&adapter->dev->dev, ctx->sglPA,
432 						 SGL_SIZE, DMA_TO_DEVICE);
433 				ctx->sglPA = 0;
434 			}
435 		} else
436 			dma_unmap_single(&adapter->dev->dev, ctx->dataPA,
437 					 bufflen, cmd->sc_data_direction);
438 	}
439 	if (cmd->sense_buffer)
440 		dma_unmap_single(&adapter->dev->dev, ctx->sensePA,
441 				 SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
442 }
443 
pvscsi_allocate_rings(struct pvscsi_adapter * adapter)444 static int pvscsi_allocate_rings(struct pvscsi_adapter *adapter)
445 {
446 	adapter->rings_state = dma_alloc_coherent(&adapter->dev->dev, PAGE_SIZE,
447 			&adapter->ringStatePA, GFP_KERNEL);
448 	if (!adapter->rings_state)
449 		return -ENOMEM;
450 
451 	adapter->req_pages = min(PVSCSI_MAX_NUM_PAGES_REQ_RING,
452 				 pvscsi_ring_pages);
453 	adapter->req_depth = adapter->req_pages
454 					* PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
455 	adapter->req_ring = dma_alloc_coherent(&adapter->dev->dev,
456 			adapter->req_pages * PAGE_SIZE, &adapter->reqRingPA,
457 			GFP_KERNEL);
458 	if (!adapter->req_ring)
459 		return -ENOMEM;
460 
461 	adapter->cmp_pages = min(PVSCSI_MAX_NUM_PAGES_CMP_RING,
462 				 pvscsi_ring_pages);
463 	adapter->cmp_ring = dma_alloc_coherent(&adapter->dev->dev,
464 			adapter->cmp_pages * PAGE_SIZE, &adapter->cmpRingPA,
465 			GFP_KERNEL);
466 	if (!adapter->cmp_ring)
467 		return -ENOMEM;
468 
469 	BUG_ON(!IS_ALIGNED(adapter->ringStatePA, PAGE_SIZE));
470 	BUG_ON(!IS_ALIGNED(adapter->reqRingPA, PAGE_SIZE));
471 	BUG_ON(!IS_ALIGNED(adapter->cmpRingPA, PAGE_SIZE));
472 
473 	if (!adapter->use_msg)
474 		return 0;
475 
476 	adapter->msg_pages = min(PVSCSI_MAX_NUM_PAGES_MSG_RING,
477 				 pvscsi_msg_ring_pages);
478 	adapter->msg_ring = dma_alloc_coherent(&adapter->dev->dev,
479 			adapter->msg_pages * PAGE_SIZE, &adapter->msgRingPA,
480 			GFP_KERNEL);
481 	if (!adapter->msg_ring)
482 		return -ENOMEM;
483 	BUG_ON(!IS_ALIGNED(adapter->msgRingPA, PAGE_SIZE));
484 
485 	return 0;
486 }
487 
pvscsi_setup_all_rings(const struct pvscsi_adapter * adapter)488 static void pvscsi_setup_all_rings(const struct pvscsi_adapter *adapter)
489 {
490 	struct PVSCSICmdDescSetupRings cmd = { 0 };
491 	dma_addr_t base;
492 	unsigned i;
493 
494 	cmd.ringsStatePPN   = adapter->ringStatePA >> PAGE_SHIFT;
495 	cmd.reqRingNumPages = adapter->req_pages;
496 	cmd.cmpRingNumPages = adapter->cmp_pages;
497 
498 	base = adapter->reqRingPA;
499 	for (i = 0; i < adapter->req_pages; i++) {
500 		cmd.reqRingPPNs[i] = base >> PAGE_SHIFT;
501 		base += PAGE_SIZE;
502 	}
503 
504 	base = adapter->cmpRingPA;
505 	for (i = 0; i < adapter->cmp_pages; i++) {
506 		cmd.cmpRingPPNs[i] = base >> PAGE_SHIFT;
507 		base += PAGE_SIZE;
508 	}
509 
510 	memset(adapter->rings_state, 0, PAGE_SIZE);
511 	memset(adapter->req_ring, 0, adapter->req_pages * PAGE_SIZE);
512 	memset(adapter->cmp_ring, 0, adapter->cmp_pages * PAGE_SIZE);
513 
514 	pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_RINGS,
515 			      &cmd, sizeof(cmd));
516 
517 	if (adapter->use_msg) {
518 		struct PVSCSICmdDescSetupMsgRing cmd_msg = { 0 };
519 
520 		cmd_msg.numPages = adapter->msg_pages;
521 
522 		base = adapter->msgRingPA;
523 		for (i = 0; i < adapter->msg_pages; i++) {
524 			cmd_msg.ringPPNs[i] = base >> PAGE_SHIFT;
525 			base += PAGE_SIZE;
526 		}
527 		memset(adapter->msg_ring, 0, adapter->msg_pages * PAGE_SIZE);
528 
529 		pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_MSG_RING,
530 				      &cmd_msg, sizeof(cmd_msg));
531 	}
532 }
533 
pvscsi_change_queue_depth(struct scsi_device * sdev,int qdepth)534 static int pvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
535 {
536 	if (!sdev->tagged_supported)
537 		qdepth = 1;
538 	return scsi_change_queue_depth(sdev, qdepth);
539 }
540 
541 /*
542  * Pull a completion descriptor off and pass the completion back
543  * to the SCSI mid layer.
544  */
pvscsi_complete_request(struct pvscsi_adapter * adapter,const struct PVSCSIRingCmpDesc * e)545 static void pvscsi_complete_request(struct pvscsi_adapter *adapter,
546 				    const struct PVSCSIRingCmpDesc *e)
547 {
548 	struct pvscsi_ctx *ctx;
549 	struct scsi_cmnd *cmd;
550 	struct completion *abort_cmp;
551 	u32 btstat = e->hostStatus;
552 	u32 sdstat = e->scsiStatus;
553 
554 	ctx = pvscsi_get_context(adapter, e->context);
555 	cmd = ctx->cmd;
556 	abort_cmp = ctx->abort_cmp;
557 	pvscsi_unmap_buffers(adapter, ctx);
558 	if (sdstat != SAM_STAT_CHECK_CONDITION)
559 		pvscsi_patch_sense(cmd);
560 	pvscsi_release_context(adapter, ctx);
561 	if (abort_cmp) {
562 		/*
563 		 * The command was requested to be aborted. Just signal that
564 		 * the request completed and swallow the actual cmd completion
565 		 * here. The abort handler will post a completion for this
566 		 * command indicating that it got successfully aborted.
567 		 */
568 		complete(abort_cmp);
569 		return;
570 	}
571 
572 	cmd->result = 0;
573 	if (sdstat != SAM_STAT_GOOD &&
574 	    (btstat == BTSTAT_SUCCESS ||
575 	     btstat == BTSTAT_LINKED_COMMAND_COMPLETED ||
576 	     btstat == BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG)) {
577 		if (sdstat == SAM_STAT_COMMAND_TERMINATED) {
578 			cmd->result = (DID_RESET << 16);
579 		} else {
580 			cmd->result = (DID_OK << 16) | sdstat;
581 			if (sdstat == SAM_STAT_CHECK_CONDITION &&
582 			    cmd->sense_buffer)
583 				cmd->result |= (DRIVER_SENSE << 24);
584 		}
585 	} else
586 		switch (btstat) {
587 		case BTSTAT_SUCCESS:
588 		case BTSTAT_LINKED_COMMAND_COMPLETED:
589 		case BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG:
590 			/*
591 			 * Commands like INQUIRY may transfer less data than
592 			 * requested by the initiator via bufflen. Set residual
593 			 * count to make upper layer aware of the actual amount
594 			 * of data returned. There are cases when controller
595 			 * returns zero dataLen with non zero data - do not set
596 			 * residual count in that case.
597 			 */
598 			if (e->dataLen && (e->dataLen < scsi_bufflen(cmd)))
599 				scsi_set_resid(cmd, scsi_bufflen(cmd) - e->dataLen);
600 			cmd->result = (DID_OK << 16);
601 			break;
602 
603 		case BTSTAT_DATARUN:
604 		case BTSTAT_DATA_UNDERRUN:
605 			/* Report residual data in underruns */
606 			scsi_set_resid(cmd, scsi_bufflen(cmd) - e->dataLen);
607 			cmd->result = (DID_ERROR << 16);
608 			break;
609 
610 		case BTSTAT_SELTIMEO:
611 			/* Our emulation returns this for non-connected devs */
612 			cmd->result = (DID_BAD_TARGET << 16);
613 			break;
614 
615 		case BTSTAT_LUNMISMATCH:
616 		case BTSTAT_TAGREJECT:
617 		case BTSTAT_BADMSG:
618 			cmd->result = (DRIVER_INVALID << 24);
619 			fallthrough;
620 
621 		case BTSTAT_HAHARDWARE:
622 		case BTSTAT_INVPHASE:
623 		case BTSTAT_HATIMEOUT:
624 		case BTSTAT_NORESPONSE:
625 		case BTSTAT_DISCONNECT:
626 		case BTSTAT_HASOFTWARE:
627 		case BTSTAT_BUSFREE:
628 		case BTSTAT_SENSFAILED:
629 			cmd->result |= (DID_ERROR << 16);
630 			break;
631 
632 		case BTSTAT_SENTRST:
633 		case BTSTAT_RECVRST:
634 		case BTSTAT_BUSRESET:
635 			cmd->result = (DID_RESET << 16);
636 			break;
637 
638 		case BTSTAT_ABORTQUEUE:
639 			cmd->result = (DID_BUS_BUSY << 16);
640 			break;
641 
642 		case BTSTAT_SCSIPARITY:
643 			cmd->result = (DID_PARITY << 16);
644 			break;
645 
646 		default:
647 			cmd->result = (DID_ERROR << 16);
648 			scmd_printk(KERN_DEBUG, cmd,
649 				    "Unknown completion status: 0x%x\n",
650 				    btstat);
651 	}
652 
653 	dev_dbg(&cmd->device->sdev_gendev,
654 		"cmd=%p %x ctx=%p result=0x%x status=0x%x,%x\n",
655 		cmd, cmd->cmnd[0], ctx, cmd->result, btstat, sdstat);
656 
657 	cmd->scsi_done(cmd);
658 }
659 
660 /*
661  * barrier usage : Since the PVSCSI device is emulated, there could be cases
662  * where we may want to serialize some accesses between the driver and the
663  * emulation layer. We use compiler barriers instead of the more expensive
664  * memory barriers because PVSCSI is only supported on X86 which has strong
665  * memory access ordering.
666  */
pvscsi_process_completion_ring(struct pvscsi_adapter * adapter)667 static void pvscsi_process_completion_ring(struct pvscsi_adapter *adapter)
668 {
669 	struct PVSCSIRingsState *s = adapter->rings_state;
670 	struct PVSCSIRingCmpDesc *ring = adapter->cmp_ring;
671 	u32 cmp_entries = s->cmpNumEntriesLog2;
672 
673 	while (s->cmpConsIdx != s->cmpProdIdx) {
674 		struct PVSCSIRingCmpDesc *e = ring + (s->cmpConsIdx &
675 						      MASK(cmp_entries));
676 		/*
677 		 * This barrier() ensures that *e is not dereferenced while
678 		 * the device emulation still writes data into the slot.
679 		 * Since the device emulation advances s->cmpProdIdx only after
680 		 * updating the slot we want to check it first.
681 		 */
682 		barrier();
683 		pvscsi_complete_request(adapter, e);
684 		/*
685 		 * This barrier() ensures that compiler doesn't reorder write
686 		 * to s->cmpConsIdx before the read of (*e) inside
687 		 * pvscsi_complete_request. Otherwise, device emulation may
688 		 * overwrite *e before we had a chance to read it.
689 		 */
690 		barrier();
691 		s->cmpConsIdx++;
692 	}
693 }
694 
695 /*
696  * Translate a Linux SCSI request into a request ring entry.
697  */
pvscsi_queue_ring(struct pvscsi_adapter * adapter,struct pvscsi_ctx * ctx,struct scsi_cmnd * cmd)698 static int pvscsi_queue_ring(struct pvscsi_adapter *adapter,
699 			     struct pvscsi_ctx *ctx, struct scsi_cmnd *cmd)
700 {
701 	struct PVSCSIRingsState *s;
702 	struct PVSCSIRingReqDesc *e;
703 	struct scsi_device *sdev;
704 	u32 req_entries;
705 
706 	s = adapter->rings_state;
707 	sdev = cmd->device;
708 	req_entries = s->reqNumEntriesLog2;
709 
710 	/*
711 	 * If this condition holds, we might have room on the request ring, but
712 	 * we might not have room on the completion ring for the response.
713 	 * However, we have already ruled out this possibility - we would not
714 	 * have successfully allocated a context if it were true, since we only
715 	 * have one context per request entry.  Check for it anyway, since it
716 	 * would be a serious bug.
717 	 */
718 	if (s->reqProdIdx - s->cmpConsIdx >= 1 << req_entries) {
719 		scmd_printk(KERN_ERR, cmd, "vmw_pvscsi: "
720 			    "ring full: reqProdIdx=%d cmpConsIdx=%d\n",
721 			    s->reqProdIdx, s->cmpConsIdx);
722 		return -1;
723 	}
724 
725 	e = adapter->req_ring + (s->reqProdIdx & MASK(req_entries));
726 
727 	e->bus    = sdev->channel;
728 	e->target = sdev->id;
729 	memset(e->lun, 0, sizeof(e->lun));
730 	e->lun[1] = sdev->lun;
731 
732 	if (cmd->sense_buffer) {
733 		ctx->sensePA = dma_map_single(&adapter->dev->dev,
734 				cmd->sense_buffer, SCSI_SENSE_BUFFERSIZE,
735 				DMA_FROM_DEVICE);
736 		if (dma_mapping_error(&adapter->dev->dev, ctx->sensePA)) {
737 			scmd_printk(KERN_DEBUG, cmd,
738 				    "vmw_pvscsi: Failed to map sense buffer for DMA.\n");
739 			ctx->sensePA = 0;
740 			return -ENOMEM;
741 		}
742 		e->senseAddr = ctx->sensePA;
743 		e->senseLen = SCSI_SENSE_BUFFERSIZE;
744 	} else {
745 		e->senseLen  = 0;
746 		e->senseAddr = 0;
747 	}
748 	e->cdbLen   = cmd->cmd_len;
749 	e->vcpuHint = smp_processor_id();
750 	memcpy(e->cdb, cmd->cmnd, e->cdbLen);
751 
752 	e->tag = SIMPLE_QUEUE_TAG;
753 
754 	if (cmd->sc_data_direction == DMA_FROM_DEVICE)
755 		e->flags = PVSCSI_FLAG_CMD_DIR_TOHOST;
756 	else if (cmd->sc_data_direction == DMA_TO_DEVICE)
757 		e->flags = PVSCSI_FLAG_CMD_DIR_TODEVICE;
758 	else if (cmd->sc_data_direction == DMA_NONE)
759 		e->flags = PVSCSI_FLAG_CMD_DIR_NONE;
760 	else
761 		e->flags = 0;
762 
763 	if (pvscsi_map_buffers(adapter, ctx, cmd, e) != 0) {
764 		if (cmd->sense_buffer) {
765 			dma_unmap_single(&adapter->dev->dev, ctx->sensePA,
766 					 SCSI_SENSE_BUFFERSIZE,
767 					 DMA_FROM_DEVICE);
768 			ctx->sensePA = 0;
769 		}
770 		return -ENOMEM;
771 	}
772 
773 	e->context = pvscsi_map_context(adapter, ctx);
774 
775 	barrier();
776 
777 	s->reqProdIdx++;
778 
779 	return 0;
780 }
781 
pvscsi_queue_lck(struct scsi_cmnd * cmd,void (* done)(struct scsi_cmnd *))782 static int pvscsi_queue_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
783 {
784 	struct Scsi_Host *host = cmd->device->host;
785 	struct pvscsi_adapter *adapter = shost_priv(host);
786 	struct pvscsi_ctx *ctx;
787 	unsigned long flags;
788 	unsigned char op;
789 
790 	spin_lock_irqsave(&adapter->hw_lock, flags);
791 
792 	ctx = pvscsi_acquire_context(adapter, cmd);
793 	if (!ctx || pvscsi_queue_ring(adapter, ctx, cmd) != 0) {
794 		if (ctx)
795 			pvscsi_release_context(adapter, ctx);
796 		spin_unlock_irqrestore(&adapter->hw_lock, flags);
797 		return SCSI_MLQUEUE_HOST_BUSY;
798 	}
799 
800 	cmd->scsi_done = done;
801 	op = cmd->cmnd[0];
802 
803 	dev_dbg(&cmd->device->sdev_gendev,
804 		"queued cmd %p, ctx %p, op=%x\n", cmd, ctx, op);
805 
806 	spin_unlock_irqrestore(&adapter->hw_lock, flags);
807 
808 	pvscsi_kick_io(adapter, op);
809 
810 	return 0;
811 }
812 
DEF_SCSI_QCMD(pvscsi_queue)813 static DEF_SCSI_QCMD(pvscsi_queue)
814 
815 static int pvscsi_abort(struct scsi_cmnd *cmd)
816 {
817 	struct pvscsi_adapter *adapter = shost_priv(cmd->device->host);
818 	struct pvscsi_ctx *ctx;
819 	unsigned long flags;
820 	int result = SUCCESS;
821 	DECLARE_COMPLETION_ONSTACK(abort_cmp);
822 	int done;
823 
824 	scmd_printk(KERN_DEBUG, cmd, "task abort on host %u, %p\n",
825 		    adapter->host->host_no, cmd);
826 
827 	spin_lock_irqsave(&adapter->hw_lock, flags);
828 
829 	/*
830 	 * Poll the completion ring first - we might be trying to abort
831 	 * a command that is waiting to be dispatched in the completion ring.
832 	 */
833 	pvscsi_process_completion_ring(adapter);
834 
835 	/*
836 	 * If there is no context for the command, it either already succeeded
837 	 * or else was never properly issued.  Not our problem.
838 	 */
839 	ctx = pvscsi_find_context(adapter, cmd);
840 	if (!ctx) {
841 		scmd_printk(KERN_DEBUG, cmd, "Failed to abort cmd %p\n", cmd);
842 		goto out;
843 	}
844 
845 	/*
846 	 * Mark that the command has been requested to be aborted and issue
847 	 * the abort.
848 	 */
849 	ctx->abort_cmp = &abort_cmp;
850 
851 	pvscsi_abort_cmd(adapter, ctx);
852 	spin_unlock_irqrestore(&adapter->hw_lock, flags);
853 	/* Wait for 2 secs for the completion. */
854 	done = wait_for_completion_timeout(&abort_cmp, msecs_to_jiffies(2000));
855 	spin_lock_irqsave(&adapter->hw_lock, flags);
856 
857 	if (!done) {
858 		/*
859 		 * Failed to abort the command, unmark the fact that it
860 		 * was requested to be aborted.
861 		 */
862 		ctx->abort_cmp = NULL;
863 		result = FAILED;
864 		scmd_printk(KERN_DEBUG, cmd,
865 			    "Failed to get completion for aborted cmd %p\n",
866 			    cmd);
867 		goto out;
868 	}
869 
870 	/*
871 	 * Successfully aborted the command.
872 	 */
873 	cmd->result = (DID_ABORT << 16);
874 	cmd->scsi_done(cmd);
875 
876 out:
877 	spin_unlock_irqrestore(&adapter->hw_lock, flags);
878 	return result;
879 }
880 
881 /*
882  * Abort all outstanding requests.  This is only safe to use if the completion
883  * ring will never be walked again or the device has been reset, because it
884  * destroys the 1-1 mapping between context field passed to emulation and our
885  * request structure.
886  */
pvscsi_reset_all(struct pvscsi_adapter * adapter)887 static void pvscsi_reset_all(struct pvscsi_adapter *adapter)
888 {
889 	unsigned i;
890 
891 	for (i = 0; i < adapter->req_depth; i++) {
892 		struct pvscsi_ctx *ctx = &adapter->cmd_map[i];
893 		struct scsi_cmnd *cmd = ctx->cmd;
894 		if (cmd) {
895 			scmd_printk(KERN_ERR, cmd,
896 				    "Forced reset on cmd %p\n", cmd);
897 			pvscsi_unmap_buffers(adapter, ctx);
898 			pvscsi_patch_sense(cmd);
899 			pvscsi_release_context(adapter, ctx);
900 			cmd->result = (DID_RESET << 16);
901 			cmd->scsi_done(cmd);
902 		}
903 	}
904 }
905 
pvscsi_host_reset(struct scsi_cmnd * cmd)906 static int pvscsi_host_reset(struct scsi_cmnd *cmd)
907 {
908 	struct Scsi_Host *host = cmd->device->host;
909 	struct pvscsi_adapter *adapter = shost_priv(host);
910 	unsigned long flags;
911 	bool use_msg;
912 
913 	scmd_printk(KERN_INFO, cmd, "SCSI Host reset\n");
914 
915 	spin_lock_irqsave(&adapter->hw_lock, flags);
916 
917 	use_msg = adapter->use_msg;
918 
919 	if (use_msg) {
920 		adapter->use_msg = false;
921 		spin_unlock_irqrestore(&adapter->hw_lock, flags);
922 
923 		/*
924 		 * Now that we know that the ISR won't add more work on the
925 		 * workqueue we can safely flush any outstanding work.
926 		 */
927 		flush_workqueue(adapter->workqueue);
928 		spin_lock_irqsave(&adapter->hw_lock, flags);
929 	}
930 
931 	/*
932 	 * We're going to tear down the entire ring structure and set it back
933 	 * up, so stalling new requests until all completions are flushed and
934 	 * the rings are back in place.
935 	 */
936 
937 	pvscsi_process_request_ring(adapter);
938 
939 	ll_adapter_reset(adapter);
940 
941 	/*
942 	 * Now process any completions.  Note we do this AFTER adapter reset,
943 	 * which is strange, but stops races where completions get posted
944 	 * between processing the ring and issuing the reset.  The backend will
945 	 * not touch the ring memory after reset, so the immediately pre-reset
946 	 * completion ring state is still valid.
947 	 */
948 	pvscsi_process_completion_ring(adapter);
949 
950 	pvscsi_reset_all(adapter);
951 	adapter->use_msg = use_msg;
952 	pvscsi_setup_all_rings(adapter);
953 	pvscsi_unmask_intr(adapter);
954 
955 	spin_unlock_irqrestore(&adapter->hw_lock, flags);
956 
957 	return SUCCESS;
958 }
959 
pvscsi_bus_reset(struct scsi_cmnd * cmd)960 static int pvscsi_bus_reset(struct scsi_cmnd *cmd)
961 {
962 	struct Scsi_Host *host = cmd->device->host;
963 	struct pvscsi_adapter *adapter = shost_priv(host);
964 	unsigned long flags;
965 
966 	scmd_printk(KERN_INFO, cmd, "SCSI Bus reset\n");
967 
968 	/*
969 	 * We don't want to queue new requests for this bus after
970 	 * flushing all pending requests to emulation, since new
971 	 * requests could then sneak in during this bus reset phase,
972 	 * so take the lock now.
973 	 */
974 	spin_lock_irqsave(&adapter->hw_lock, flags);
975 
976 	pvscsi_process_request_ring(adapter);
977 	ll_bus_reset(adapter);
978 	pvscsi_process_completion_ring(adapter);
979 
980 	spin_unlock_irqrestore(&adapter->hw_lock, flags);
981 
982 	return SUCCESS;
983 }
984 
pvscsi_device_reset(struct scsi_cmnd * cmd)985 static int pvscsi_device_reset(struct scsi_cmnd *cmd)
986 {
987 	struct Scsi_Host *host = cmd->device->host;
988 	struct pvscsi_adapter *adapter = shost_priv(host);
989 	unsigned long flags;
990 
991 	scmd_printk(KERN_INFO, cmd, "SCSI device reset on scsi%u:%u\n",
992 		    host->host_no, cmd->device->id);
993 
994 	/*
995 	 * We don't want to queue new requests for this device after flushing
996 	 * all pending requests to emulation, since new requests could then
997 	 * sneak in during this device reset phase, so take the lock now.
998 	 */
999 	spin_lock_irqsave(&adapter->hw_lock, flags);
1000 
1001 	pvscsi_process_request_ring(adapter);
1002 	ll_device_reset(adapter, cmd->device->id);
1003 	pvscsi_process_completion_ring(adapter);
1004 
1005 	spin_unlock_irqrestore(&adapter->hw_lock, flags);
1006 
1007 	return SUCCESS;
1008 }
1009 
1010 static struct scsi_host_template pvscsi_template;
1011 
pvscsi_info(struct Scsi_Host * host)1012 static const char *pvscsi_info(struct Scsi_Host *host)
1013 {
1014 	struct pvscsi_adapter *adapter = shost_priv(host);
1015 	static char buf[256];
1016 
1017 	sprintf(buf, "VMware PVSCSI storage adapter rev %d, req/cmp/msg rings: "
1018 		"%u/%u/%u pages, cmd_per_lun=%u", adapter->rev,
1019 		adapter->req_pages, adapter->cmp_pages, adapter->msg_pages,
1020 		pvscsi_template.cmd_per_lun);
1021 
1022 	return buf;
1023 }
1024 
1025 static struct scsi_host_template pvscsi_template = {
1026 	.module				= THIS_MODULE,
1027 	.name				= "VMware PVSCSI Host Adapter",
1028 	.proc_name			= "vmw_pvscsi",
1029 	.info				= pvscsi_info,
1030 	.queuecommand			= pvscsi_queue,
1031 	.this_id			= -1,
1032 	.sg_tablesize			= PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT,
1033 	.dma_boundary			= UINT_MAX,
1034 	.max_sectors			= 0xffff,
1035 	.change_queue_depth		= pvscsi_change_queue_depth,
1036 	.eh_abort_handler		= pvscsi_abort,
1037 	.eh_device_reset_handler	= pvscsi_device_reset,
1038 	.eh_bus_reset_handler		= pvscsi_bus_reset,
1039 	.eh_host_reset_handler		= pvscsi_host_reset,
1040 };
1041 
pvscsi_process_msg(const struct pvscsi_adapter * adapter,const struct PVSCSIRingMsgDesc * e)1042 static void pvscsi_process_msg(const struct pvscsi_adapter *adapter,
1043 			       const struct PVSCSIRingMsgDesc *e)
1044 {
1045 	struct PVSCSIRingsState *s = adapter->rings_state;
1046 	struct Scsi_Host *host = adapter->host;
1047 	struct scsi_device *sdev;
1048 
1049 	printk(KERN_INFO "vmw_pvscsi: msg type: 0x%x - MSG RING: %u/%u (%u) \n",
1050 	       e->type, s->msgProdIdx, s->msgConsIdx, s->msgNumEntriesLog2);
1051 
1052 	BUILD_BUG_ON(PVSCSI_MSG_LAST != 2);
1053 
1054 	if (e->type == PVSCSI_MSG_DEV_ADDED) {
1055 		struct PVSCSIMsgDescDevStatusChanged *desc;
1056 		desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
1057 
1058 		printk(KERN_INFO
1059 		       "vmw_pvscsi: msg: device added at scsi%u:%u:%u\n",
1060 		       desc->bus, desc->target, desc->lun[1]);
1061 
1062 		if (!scsi_host_get(host))
1063 			return;
1064 
1065 		sdev = scsi_device_lookup(host, desc->bus, desc->target,
1066 					  desc->lun[1]);
1067 		if (sdev) {
1068 			printk(KERN_INFO "vmw_pvscsi: device already exists\n");
1069 			scsi_device_put(sdev);
1070 		} else
1071 			scsi_add_device(adapter->host, desc->bus,
1072 					desc->target, desc->lun[1]);
1073 
1074 		scsi_host_put(host);
1075 	} else if (e->type == PVSCSI_MSG_DEV_REMOVED) {
1076 		struct PVSCSIMsgDescDevStatusChanged *desc;
1077 		desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
1078 
1079 		printk(KERN_INFO
1080 		       "vmw_pvscsi: msg: device removed at scsi%u:%u:%u\n",
1081 		       desc->bus, desc->target, desc->lun[1]);
1082 
1083 		if (!scsi_host_get(host))
1084 			return;
1085 
1086 		sdev = scsi_device_lookup(host, desc->bus, desc->target,
1087 					  desc->lun[1]);
1088 		if (sdev) {
1089 			scsi_remove_device(sdev);
1090 			scsi_device_put(sdev);
1091 		} else
1092 			printk(KERN_INFO
1093 			       "vmw_pvscsi: failed to lookup scsi%u:%u:%u\n",
1094 			       desc->bus, desc->target, desc->lun[1]);
1095 
1096 		scsi_host_put(host);
1097 	}
1098 }
1099 
pvscsi_msg_pending(const struct pvscsi_adapter * adapter)1100 static int pvscsi_msg_pending(const struct pvscsi_adapter *adapter)
1101 {
1102 	struct PVSCSIRingsState *s = adapter->rings_state;
1103 
1104 	return s->msgProdIdx != s->msgConsIdx;
1105 }
1106 
pvscsi_process_msg_ring(const struct pvscsi_adapter * adapter)1107 static void pvscsi_process_msg_ring(const struct pvscsi_adapter *adapter)
1108 {
1109 	struct PVSCSIRingsState *s = adapter->rings_state;
1110 	struct PVSCSIRingMsgDesc *ring = adapter->msg_ring;
1111 	u32 msg_entries = s->msgNumEntriesLog2;
1112 
1113 	while (pvscsi_msg_pending(adapter)) {
1114 		struct PVSCSIRingMsgDesc *e = ring + (s->msgConsIdx &
1115 						      MASK(msg_entries));
1116 
1117 		barrier();
1118 		pvscsi_process_msg(adapter, e);
1119 		barrier();
1120 		s->msgConsIdx++;
1121 	}
1122 }
1123 
pvscsi_msg_workqueue_handler(struct work_struct * data)1124 static void pvscsi_msg_workqueue_handler(struct work_struct *data)
1125 {
1126 	struct pvscsi_adapter *adapter;
1127 
1128 	adapter = container_of(data, struct pvscsi_adapter, work);
1129 
1130 	pvscsi_process_msg_ring(adapter);
1131 }
1132 
pvscsi_setup_msg_workqueue(struct pvscsi_adapter * adapter)1133 static int pvscsi_setup_msg_workqueue(struct pvscsi_adapter *adapter)
1134 {
1135 	char name[32];
1136 
1137 	if (!pvscsi_use_msg)
1138 		return 0;
1139 
1140 	pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND,
1141 			 PVSCSI_CMD_SETUP_MSG_RING);
1142 
1143 	if (pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS) == -1)
1144 		return 0;
1145 
1146 	snprintf(name, sizeof(name),
1147 		 "vmw_pvscsi_wq_%u", adapter->host->host_no);
1148 
1149 	adapter->workqueue = create_singlethread_workqueue(name);
1150 	if (!adapter->workqueue) {
1151 		printk(KERN_ERR "vmw_pvscsi: failed to create work queue\n");
1152 		return 0;
1153 	}
1154 	INIT_WORK(&adapter->work, pvscsi_msg_workqueue_handler);
1155 
1156 	return 1;
1157 }
1158 
pvscsi_setup_req_threshold(struct pvscsi_adapter * adapter,bool enable)1159 static bool pvscsi_setup_req_threshold(struct pvscsi_adapter *adapter,
1160 				      bool enable)
1161 {
1162 	u32 val;
1163 
1164 	if (!pvscsi_use_req_threshold)
1165 		return false;
1166 
1167 	pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND,
1168 			 PVSCSI_CMD_SETUP_REQCALLTHRESHOLD);
1169 	val = pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS);
1170 	if (val == -1) {
1171 		printk(KERN_INFO "vmw_pvscsi: device does not support req_threshold\n");
1172 		return false;
1173 	} else {
1174 		struct PVSCSICmdDescSetupReqCall cmd_msg = { 0 };
1175 		cmd_msg.enable = enable;
1176 		printk(KERN_INFO
1177 		       "vmw_pvscsi: %sabling reqCallThreshold\n",
1178 			enable ? "en" : "dis");
1179 		pvscsi_write_cmd_desc(adapter,
1180 				      PVSCSI_CMD_SETUP_REQCALLTHRESHOLD,
1181 				      &cmd_msg, sizeof(cmd_msg));
1182 		return pvscsi_reg_read(adapter,
1183 				       PVSCSI_REG_OFFSET_COMMAND_STATUS) != 0;
1184 	}
1185 }
1186 
pvscsi_isr(int irq,void * devp)1187 static irqreturn_t pvscsi_isr(int irq, void *devp)
1188 {
1189 	struct pvscsi_adapter *adapter = devp;
1190 	unsigned long flags;
1191 
1192 	spin_lock_irqsave(&adapter->hw_lock, flags);
1193 	pvscsi_process_completion_ring(adapter);
1194 	if (adapter->use_msg && pvscsi_msg_pending(adapter))
1195 		queue_work(adapter->workqueue, &adapter->work);
1196 	spin_unlock_irqrestore(&adapter->hw_lock, flags);
1197 
1198 	return IRQ_HANDLED;
1199 }
1200 
pvscsi_shared_isr(int irq,void * devp)1201 static irqreturn_t pvscsi_shared_isr(int irq, void *devp)
1202 {
1203 	struct pvscsi_adapter *adapter = devp;
1204 	u32 val = pvscsi_read_intr_status(adapter);
1205 
1206 	if (!(val & PVSCSI_INTR_ALL_SUPPORTED))
1207 		return IRQ_NONE;
1208 	pvscsi_write_intr_status(devp, val);
1209 	return pvscsi_isr(irq, devp);
1210 }
1211 
pvscsi_free_sgls(const struct pvscsi_adapter * adapter)1212 static void pvscsi_free_sgls(const struct pvscsi_adapter *adapter)
1213 {
1214 	struct pvscsi_ctx *ctx = adapter->cmd_map;
1215 	unsigned i;
1216 
1217 	for (i = 0; i < adapter->req_depth; ++i, ++ctx)
1218 		free_pages((unsigned long)ctx->sgl, get_order(SGL_SIZE));
1219 }
1220 
pvscsi_shutdown_intr(struct pvscsi_adapter * adapter)1221 static void pvscsi_shutdown_intr(struct pvscsi_adapter *adapter)
1222 {
1223 	free_irq(pci_irq_vector(adapter->dev, 0), adapter);
1224 	pci_free_irq_vectors(adapter->dev);
1225 }
1226 
pvscsi_release_resources(struct pvscsi_adapter * adapter)1227 static void pvscsi_release_resources(struct pvscsi_adapter *adapter)
1228 {
1229 	if (adapter->workqueue)
1230 		destroy_workqueue(adapter->workqueue);
1231 
1232 	if (adapter->mmioBase)
1233 		pci_iounmap(adapter->dev, adapter->mmioBase);
1234 
1235 	pci_release_regions(adapter->dev);
1236 
1237 	if (adapter->cmd_map) {
1238 		pvscsi_free_sgls(adapter);
1239 		kfree(adapter->cmd_map);
1240 	}
1241 
1242 	if (adapter->rings_state)
1243 		dma_free_coherent(&adapter->dev->dev, PAGE_SIZE,
1244 				    adapter->rings_state, adapter->ringStatePA);
1245 
1246 	if (adapter->req_ring)
1247 		dma_free_coherent(&adapter->dev->dev,
1248 				    adapter->req_pages * PAGE_SIZE,
1249 				    adapter->req_ring, adapter->reqRingPA);
1250 
1251 	if (adapter->cmp_ring)
1252 		dma_free_coherent(&adapter->dev->dev,
1253 				    adapter->cmp_pages * PAGE_SIZE,
1254 				    adapter->cmp_ring, adapter->cmpRingPA);
1255 
1256 	if (adapter->msg_ring)
1257 		dma_free_coherent(&adapter->dev->dev,
1258 				    adapter->msg_pages * PAGE_SIZE,
1259 				    adapter->msg_ring, adapter->msgRingPA);
1260 }
1261 
1262 /*
1263  * Allocate scatter gather lists.
1264  *
1265  * These are statically allocated.  Trying to be clever was not worth it.
1266  *
1267  * Dynamic allocation can fail, and we can't go deep into the memory
1268  * allocator, since we're a SCSI driver, and trying too hard to allocate
1269  * memory might generate disk I/O.  We also don't want to fail disk I/O
1270  * in that case because we can't get an allocation - the I/O could be
1271  * trying to swap out data to free memory.  Since that is pathological,
1272  * just use a statically allocated scatter list.
1273  *
1274  */
pvscsi_allocate_sg(struct pvscsi_adapter * adapter)1275 static int pvscsi_allocate_sg(struct pvscsi_adapter *adapter)
1276 {
1277 	struct pvscsi_ctx *ctx;
1278 	int i;
1279 
1280 	ctx = adapter->cmd_map;
1281 	BUILD_BUG_ON(sizeof(struct pvscsi_sg_list) > SGL_SIZE);
1282 
1283 	for (i = 0; i < adapter->req_depth; ++i, ++ctx) {
1284 		ctx->sgl = (void *)__get_free_pages(GFP_KERNEL,
1285 						    get_order(SGL_SIZE));
1286 		ctx->sglPA = 0;
1287 		BUG_ON(!IS_ALIGNED(((unsigned long)ctx->sgl), PAGE_SIZE));
1288 		if (!ctx->sgl) {
1289 			for (; i >= 0; --i, --ctx) {
1290 				free_pages((unsigned long)ctx->sgl,
1291 					   get_order(SGL_SIZE));
1292 				ctx->sgl = NULL;
1293 			}
1294 			return -ENOMEM;
1295 		}
1296 	}
1297 
1298 	return 0;
1299 }
1300 
1301 /*
1302  * Query the device, fetch the config info and return the
1303  * maximum number of targets on the adapter. In case of
1304  * failure due to any reason return default i.e. 16.
1305  */
pvscsi_get_max_targets(struct pvscsi_adapter * adapter)1306 static u32 pvscsi_get_max_targets(struct pvscsi_adapter *adapter)
1307 {
1308 	struct PVSCSICmdDescConfigCmd cmd;
1309 	struct PVSCSIConfigPageHeader *header;
1310 	struct device *dev;
1311 	dma_addr_t configPagePA;
1312 	void *config_page;
1313 	u32 numPhys = 16;
1314 
1315 	dev = pvscsi_dev(adapter);
1316 	config_page = dma_alloc_coherent(&adapter->dev->dev, PAGE_SIZE,
1317 			&configPagePA, GFP_KERNEL);
1318 	if (!config_page) {
1319 		dev_warn(dev, "vmw_pvscsi: failed to allocate memory for config page\n");
1320 		goto exit;
1321 	}
1322 	BUG_ON(configPagePA & ~PAGE_MASK);
1323 
1324 	/* Fetch config info from the device. */
1325 	cmd.configPageAddress = ((u64)PVSCSI_CONFIG_CONTROLLER_ADDRESS) << 32;
1326 	cmd.configPageNum = PVSCSI_CONFIG_PAGE_CONTROLLER;
1327 	cmd.cmpAddr = configPagePA;
1328 	cmd._pad = 0;
1329 
1330 	/*
1331 	 * Mark the completion page header with error values. If the device
1332 	 * completes the command successfully, it sets the status values to
1333 	 * indicate success.
1334 	 */
1335 	header = config_page;
1336 	memset(header, 0, sizeof *header);
1337 	header->hostStatus = BTSTAT_INVPARAM;
1338 	header->scsiStatus = SDSTAT_CHECK;
1339 
1340 	pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_CONFIG, &cmd, sizeof cmd);
1341 
1342 	if (header->hostStatus == BTSTAT_SUCCESS &&
1343 	    header->scsiStatus == SDSTAT_GOOD) {
1344 		struct PVSCSIConfigPageController *config;
1345 
1346 		config = config_page;
1347 		numPhys = config->numPhys;
1348 	} else
1349 		dev_warn(dev, "vmw_pvscsi: PVSCSI_CMD_CONFIG failed. hostStatus = 0x%x, scsiStatus = 0x%x\n",
1350 			 header->hostStatus, header->scsiStatus);
1351 	dma_free_coherent(&adapter->dev->dev, PAGE_SIZE, config_page,
1352 			  configPagePA);
1353 exit:
1354 	return numPhys;
1355 }
1356 
pvscsi_probe(struct pci_dev * pdev,const struct pci_device_id * id)1357 static int pvscsi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1358 {
1359 	unsigned int irq_flag = PCI_IRQ_MSIX | PCI_IRQ_MSI | PCI_IRQ_LEGACY;
1360 	struct pvscsi_adapter *adapter;
1361 	struct pvscsi_adapter adapter_temp;
1362 	struct Scsi_Host *host = NULL;
1363 	unsigned int i;
1364 	int error;
1365 	u32 max_id;
1366 
1367 	error = -ENODEV;
1368 
1369 	if (pci_enable_device(pdev))
1370 		return error;
1371 
1372 	if (!dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64))) {
1373 		printk(KERN_INFO "vmw_pvscsi: using 64bit dma\n");
1374 	} else if (!dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32))) {
1375 		printk(KERN_INFO "vmw_pvscsi: using 32bit dma\n");
1376 	} else {
1377 		printk(KERN_ERR "vmw_pvscsi: failed to set DMA mask\n");
1378 		goto out_disable_device;
1379 	}
1380 
1381 	/*
1382 	 * Let's use a temp pvscsi_adapter struct until we find the number of
1383 	 * targets on the adapter, after that we will switch to the real
1384 	 * allocated struct.
1385 	 */
1386 	adapter = &adapter_temp;
1387 	memset(adapter, 0, sizeof(*adapter));
1388 	adapter->dev  = pdev;
1389 	adapter->rev = pdev->revision;
1390 
1391 	if (pci_request_regions(pdev, "vmw_pvscsi")) {
1392 		printk(KERN_ERR "vmw_pvscsi: pci memory selection failed\n");
1393 		goto out_disable_device;
1394 	}
1395 
1396 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
1397 		if ((pci_resource_flags(pdev, i) & PCI_BASE_ADDRESS_SPACE_IO))
1398 			continue;
1399 
1400 		if (pci_resource_len(pdev, i) < PVSCSI_MEM_SPACE_SIZE)
1401 			continue;
1402 
1403 		break;
1404 	}
1405 
1406 	if (i == DEVICE_COUNT_RESOURCE) {
1407 		printk(KERN_ERR
1408 		       "vmw_pvscsi: adapter has no suitable MMIO region\n");
1409 		goto out_release_resources_and_disable;
1410 	}
1411 
1412 	adapter->mmioBase = pci_iomap(pdev, i, PVSCSI_MEM_SPACE_SIZE);
1413 
1414 	if (!adapter->mmioBase) {
1415 		printk(KERN_ERR
1416 		       "vmw_pvscsi: can't iomap for BAR %d memsize %lu\n",
1417 		       i, PVSCSI_MEM_SPACE_SIZE);
1418 		goto out_release_resources_and_disable;
1419 	}
1420 
1421 	pci_set_master(pdev);
1422 
1423 	/*
1424 	 * Ask the device for max number of targets before deciding the
1425 	 * default pvscsi_ring_pages value.
1426 	 */
1427 	max_id = pvscsi_get_max_targets(adapter);
1428 	printk(KERN_INFO "vmw_pvscsi: max_id: %u\n", max_id);
1429 
1430 	if (pvscsi_ring_pages == 0)
1431 		/*
1432 		 * Set the right default value. Up to 16 it is 8, above it is
1433 		 * max.
1434 		 */
1435 		pvscsi_ring_pages = (max_id > 16) ?
1436 			PVSCSI_SETUP_RINGS_MAX_NUM_PAGES :
1437 			PVSCSI_DEFAULT_NUM_PAGES_PER_RING;
1438 	printk(KERN_INFO
1439 	       "vmw_pvscsi: setting ring_pages to %d\n",
1440 	       pvscsi_ring_pages);
1441 
1442 	pvscsi_template.can_queue =
1443 		min(PVSCSI_MAX_NUM_PAGES_REQ_RING, pvscsi_ring_pages) *
1444 		PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
1445 	pvscsi_template.cmd_per_lun =
1446 		min(pvscsi_template.can_queue, pvscsi_cmd_per_lun);
1447 	host = scsi_host_alloc(&pvscsi_template, sizeof(struct pvscsi_adapter));
1448 	if (!host) {
1449 		printk(KERN_ERR "vmw_pvscsi: failed to allocate host\n");
1450 		goto out_release_resources_and_disable;
1451 	}
1452 
1453 	/*
1454 	 * Let's use the real pvscsi_adapter struct here onwards.
1455 	 */
1456 	adapter = shost_priv(host);
1457 	memset(adapter, 0, sizeof(*adapter));
1458 	adapter->dev  = pdev;
1459 	adapter->host = host;
1460 	/*
1461 	 * Copy back what we already have to the allocated adapter struct.
1462 	 */
1463 	adapter->rev = adapter_temp.rev;
1464 	adapter->mmioBase = adapter_temp.mmioBase;
1465 
1466 	spin_lock_init(&adapter->hw_lock);
1467 	host->max_channel = 0;
1468 	host->max_lun     = 1;
1469 	host->max_cmd_len = 16;
1470 	host->max_id      = max_id;
1471 
1472 	pci_set_drvdata(pdev, host);
1473 
1474 	ll_adapter_reset(adapter);
1475 
1476 	adapter->use_msg = pvscsi_setup_msg_workqueue(adapter);
1477 
1478 	error = pvscsi_allocate_rings(adapter);
1479 	if (error) {
1480 		printk(KERN_ERR "vmw_pvscsi: unable to allocate ring memory\n");
1481 		goto out_release_resources;
1482 	}
1483 
1484 	/*
1485 	 * From this point on we should reset the adapter if anything goes
1486 	 * wrong.
1487 	 */
1488 	pvscsi_setup_all_rings(adapter);
1489 
1490 	adapter->cmd_map = kcalloc(adapter->req_depth,
1491 				   sizeof(struct pvscsi_ctx), GFP_KERNEL);
1492 	if (!adapter->cmd_map) {
1493 		printk(KERN_ERR "vmw_pvscsi: failed to allocate memory.\n");
1494 		error = -ENOMEM;
1495 		goto out_reset_adapter;
1496 	}
1497 
1498 	INIT_LIST_HEAD(&adapter->cmd_pool);
1499 	for (i = 0; i < adapter->req_depth; i++) {
1500 		struct pvscsi_ctx *ctx = adapter->cmd_map + i;
1501 		list_add(&ctx->list, &adapter->cmd_pool);
1502 	}
1503 
1504 	error = pvscsi_allocate_sg(adapter);
1505 	if (error) {
1506 		printk(KERN_ERR "vmw_pvscsi: unable to allocate s/g table\n");
1507 		goto out_reset_adapter;
1508 	}
1509 
1510 	if (pvscsi_disable_msix)
1511 		irq_flag &= ~PCI_IRQ_MSIX;
1512 	if (pvscsi_disable_msi)
1513 		irq_flag &= ~PCI_IRQ_MSI;
1514 
1515 	error = pci_alloc_irq_vectors(adapter->dev, 1, 1, irq_flag);
1516 	if (error < 0)
1517 		goto out_reset_adapter;
1518 
1519 	adapter->use_req_threshold = pvscsi_setup_req_threshold(adapter, true);
1520 	printk(KERN_DEBUG "vmw_pvscsi: driver-based request coalescing %sabled\n",
1521 	       adapter->use_req_threshold ? "en" : "dis");
1522 
1523 	if (adapter->dev->msix_enabled || adapter->dev->msi_enabled) {
1524 		printk(KERN_INFO "vmw_pvscsi: using MSI%s\n",
1525 			adapter->dev->msix_enabled ? "-X" : "");
1526 		error = request_irq(pci_irq_vector(pdev, 0), pvscsi_isr,
1527 				0, "vmw_pvscsi", adapter);
1528 	} else {
1529 		printk(KERN_INFO "vmw_pvscsi: using INTx\n");
1530 		error = request_irq(pci_irq_vector(pdev, 0), pvscsi_shared_isr,
1531 				IRQF_SHARED, "vmw_pvscsi", adapter);
1532 	}
1533 
1534 	if (error) {
1535 		printk(KERN_ERR
1536 		       "vmw_pvscsi: unable to request IRQ: %d\n", error);
1537 		goto out_reset_adapter;
1538 	}
1539 
1540 	error = scsi_add_host(host, &pdev->dev);
1541 	if (error) {
1542 		printk(KERN_ERR
1543 		       "vmw_pvscsi: scsi_add_host failed: %d\n", error);
1544 		goto out_reset_adapter;
1545 	}
1546 
1547 	dev_info(&pdev->dev, "VMware PVSCSI rev %d host #%u\n",
1548 		 adapter->rev, host->host_no);
1549 
1550 	pvscsi_unmask_intr(adapter);
1551 
1552 	scsi_scan_host(host);
1553 
1554 	return 0;
1555 
1556 out_reset_adapter:
1557 	ll_adapter_reset(adapter);
1558 out_release_resources:
1559 	pvscsi_shutdown_intr(adapter);
1560 	pvscsi_release_resources(adapter);
1561 	scsi_host_put(host);
1562 out_disable_device:
1563 	pci_disable_device(pdev);
1564 
1565 	return error;
1566 
1567 out_release_resources_and_disable:
1568 	pvscsi_shutdown_intr(adapter);
1569 	pvscsi_release_resources(adapter);
1570 	goto out_disable_device;
1571 }
1572 
__pvscsi_shutdown(struct pvscsi_adapter * adapter)1573 static void __pvscsi_shutdown(struct pvscsi_adapter *adapter)
1574 {
1575 	pvscsi_mask_intr(adapter);
1576 
1577 	if (adapter->workqueue)
1578 		flush_workqueue(adapter->workqueue);
1579 
1580 	pvscsi_shutdown_intr(adapter);
1581 
1582 	pvscsi_process_request_ring(adapter);
1583 	pvscsi_process_completion_ring(adapter);
1584 	ll_adapter_reset(adapter);
1585 }
1586 
pvscsi_shutdown(struct pci_dev * dev)1587 static void pvscsi_shutdown(struct pci_dev *dev)
1588 {
1589 	struct Scsi_Host *host = pci_get_drvdata(dev);
1590 	struct pvscsi_adapter *adapter = shost_priv(host);
1591 
1592 	__pvscsi_shutdown(adapter);
1593 }
1594 
pvscsi_remove(struct pci_dev * pdev)1595 static void pvscsi_remove(struct pci_dev *pdev)
1596 {
1597 	struct Scsi_Host *host = pci_get_drvdata(pdev);
1598 	struct pvscsi_adapter *adapter = shost_priv(host);
1599 
1600 	scsi_remove_host(host);
1601 
1602 	__pvscsi_shutdown(adapter);
1603 	pvscsi_release_resources(adapter);
1604 
1605 	scsi_host_put(host);
1606 
1607 	pci_disable_device(pdev);
1608 }
1609 
1610 static struct pci_driver pvscsi_pci_driver = {
1611 	.name		= "vmw_pvscsi",
1612 	.id_table	= pvscsi_pci_tbl,
1613 	.probe		= pvscsi_probe,
1614 	.remove		= pvscsi_remove,
1615 	.shutdown       = pvscsi_shutdown,
1616 };
1617 
pvscsi_init(void)1618 static int __init pvscsi_init(void)
1619 {
1620 	pr_info("%s - version %s\n",
1621 		PVSCSI_LINUX_DRIVER_DESC, PVSCSI_DRIVER_VERSION_STRING);
1622 	return pci_register_driver(&pvscsi_pci_driver);
1623 }
1624 
pvscsi_exit(void)1625 static void __exit pvscsi_exit(void)
1626 {
1627 	pci_unregister_driver(&pvscsi_pci_driver);
1628 }
1629 
1630 module_init(pvscsi_init);
1631 module_exit(pvscsi_exit);
1632