xref: /openbmc/linux/drivers/scsi/isci/request.h (revision 67ea838d17acdad3331aeae848683c768df96aaa)
1 /*
2  * This file is provided under a dual BSD/GPLv2 license.  When using or
3  * redistributing this file, you may do so under either license.
4  *
5  * GPL LICENSE SUMMARY
6  *
7  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of version 2 of the GNU General Public License as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
21  * The full GNU General Public License is included in this distribution
22  * in the file called LICENSE.GPL.
23  *
24  * BSD LICENSE
25  *
26  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
27  * All rights reserved.
28  *
29  * Redistribution and use in source and binary forms, with or without
30  * modification, are permitted provided that the following conditions
31  * are met:
32  *
33  *   * Redistributions of source code must retain the above copyright
34  *     notice, this list of conditions and the following disclaimer.
35  *   * Redistributions in binary form must reproduce the above copyright
36  *     notice, this list of conditions and the following disclaimer in
37  *     the documentation and/or other materials provided with the
38  *     distribution.
39  *   * Neither the name of Intel Corporation nor the names of its
40  *     contributors may be used to endorse or promote products derived
41  *     from this software without specific prior written permission.
42  *
43  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
44  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
45  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
46  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
47  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
48  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
49  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
50  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
51  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
52  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
53  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
54  */
55 
56 #ifndef _ISCI_REQUEST_H_
57 #define _ISCI_REQUEST_H_
58 
59 #include "isci.h"
60 #include "scic_sds_request.h"
61 
62 /**
63  * struct isci_request_status - This enum defines the possible states of an I/O
64  *    request.
65  *
66  *
67  */
68 enum isci_request_status {
69 	unallocated = 0x00,
70 	allocated   = 0x01,
71 	started     = 0x02,
72 	completed   = 0x03,
73 	aborting    = 0x04,
74 	aborted     = 0x05,
75 	terminating = 0x06,
76 	dead        = 0x07
77 };
78 
79 enum task_type {
80 	io_task  = 0,
81 	tmf_task = 1
82 };
83 
84 struct isci_request {
85 	enum isci_request_status status;
86 	enum task_type ttype;
87 	unsigned short io_tag;
88 	bool complete_in_target;
89 	bool terminated;
90 
91 	union ttype_ptr_union {
92 		struct sas_task *io_task_ptr;   /* When ttype==io_task  */
93 		struct isci_tmf *tmf_task_ptr;  /* When ttype==tmf_task */
94 	} ttype_ptr;
95 	struct isci_host *isci_host;
96 	struct isci_remote_device *isci_device;
97 	/* For use in the requests_to_{complete|abort} lists: */
98 	struct list_head completed_node;
99 	/* For use in the reqs_in_process list: */
100 	struct list_head dev_node;
101 	spinlock_t state_lock;
102 	dma_addr_t request_daddr;
103 	dma_addr_t zero_scatter_daddr;
104 
105 	unsigned int num_sg_entries;                    /* returned by pci_alloc_sg */
106 
107 	/** Note: "io_request_completion" is completed in two different ways
108 	 * depending on whether this is a TMF or regular request.
109 	 * - TMF requests are completed in the thread that started them;
110 	 * - regular requests are completed in the request completion callback
111 	 *   function.
112 	 * This difference in operation allows the aborter of a TMF request
113 	 * to be sure that once the TMF request completes, the I/O that the
114 	 * TMF was aborting is guaranteed to have completed.
115 	 */
116 	struct completion *io_request_completion;
117 	struct scic_sds_request sci;
118 };
119 
120 static inline struct isci_request *sci_req_to_ireq(struct scic_sds_request *sci_req)
121 {
122 	struct isci_request *ireq = container_of(sci_req, typeof(*ireq), sci);
123 
124 	return ireq;
125 }
126 
127 /**
128  * This function gets the status of the request object.
129  * @request: This parameter points to the isci_request object
130  *
131  * status of the object as a isci_request_status enum.
132  */
133 static inline
134 enum isci_request_status isci_request_get_state(
135 	struct isci_request *isci_request)
136 {
137 	BUG_ON(isci_request == NULL);
138 
139 	/*probably a bad sign...	*/
140 	if (isci_request->status == unallocated)
141 		dev_warn(&isci_request->isci_host->pdev->dev,
142 			 "%s: isci_request->status == unallocated\n",
143 			 __func__);
144 
145 	return isci_request->status;
146 }
147 
148 
149 /**
150  * isci_request_change_state() - This function sets the status of the request
151  *    object.
152  * @request: This parameter points to the isci_request object
153  * @status: This Parameter is the new status of the object
154  *
155  */
156 static inline enum isci_request_status isci_request_change_state(
157 	struct isci_request *isci_request,
158 	enum isci_request_status status)
159 {
160 	enum isci_request_status old_state;
161 	unsigned long flags;
162 
163 	dev_dbg(&isci_request->isci_host->pdev->dev,
164 		"%s: isci_request = %p, state = 0x%x\n",
165 		__func__,
166 		isci_request,
167 		status);
168 
169 	BUG_ON(isci_request == NULL);
170 
171 	spin_lock_irqsave(&isci_request->state_lock, flags);
172 	old_state = isci_request->status;
173 	isci_request->status = status;
174 	spin_unlock_irqrestore(&isci_request->state_lock, flags);
175 
176 	return old_state;
177 }
178 
179 /**
180  * isci_request_change_started_to_newstate() - This function sets the status of
181  *    the request object.
182  * @request: This parameter points to the isci_request object
183  * @status: This Parameter is the new status of the object
184  *
185  * state previous to any change.
186  */
187 static inline enum isci_request_status isci_request_change_started_to_newstate(
188 	struct isci_request *isci_request,
189 	struct completion *completion_ptr,
190 	enum isci_request_status newstate)
191 {
192 	enum isci_request_status old_state;
193 	unsigned long flags;
194 
195 	spin_lock_irqsave(&isci_request->state_lock, flags);
196 
197 	old_state = isci_request->status;
198 
199 	if (old_state == started || old_state == aborting) {
200 		BUG_ON(isci_request->io_request_completion != NULL);
201 
202 		isci_request->io_request_completion = completion_ptr;
203 		isci_request->status = newstate;
204 	}
205 	spin_unlock_irqrestore(&isci_request->state_lock, flags);
206 
207 	dev_dbg(&isci_request->isci_host->pdev->dev,
208 		"%s: isci_request = %p, old_state = 0x%x\n",
209 		__func__,
210 		isci_request,
211 		old_state);
212 
213 	return old_state;
214 }
215 
216 /**
217  * isci_request_change_started_to_aborted() - This function sets the status of
218  *    the request object.
219  * @request: This parameter points to the isci_request object
220  * @completion_ptr: This parameter is saved as the kernel completion structure
221  *    signalled when the old request completes.
222  *
223  * state previous to any change.
224  */
225 static inline enum isci_request_status isci_request_change_started_to_aborted(
226 	struct isci_request *isci_request,
227 	struct completion *completion_ptr)
228 {
229 	return isci_request_change_started_to_newstate(
230 		       isci_request, completion_ptr, aborted
231 		       );
232 }
233 /**
234  * isci_request_free() - This function frees the request object.
235  * @isci_host: This parameter specifies the ISCI host object
236  * @isci_request: This parameter points to the isci_request object
237  *
238  */
239 static inline void isci_request_free(
240 	struct isci_host *isci_host,
241 	struct isci_request *isci_request)
242 {
243 	if (!isci_request)
244 		return;
245 
246 	/* release the dma memory if we fail. */
247 	dma_pool_free(isci_host->dma_pool, isci_request,
248 		      isci_request->request_daddr);
249 }
250 
251 
252 /* #define ISCI_REQUEST_VALIDATE_ACCESS
253  */
254 
255 #ifdef ISCI_REQUEST_VALIDATE_ACCESS
256 
257 static inline
258 struct sas_task *isci_request_access_task(struct isci_request *isci_request)
259 {
260 	BUG_ON(isci_request->ttype != io_task);
261 	return isci_request->ttype_ptr.io_task_ptr;
262 }
263 
264 static inline
265 struct isci_tmf *isci_request_access_tmf(struct isci_request *isci_request)
266 {
267 	BUG_ON(isci_request->ttype != tmf_task);
268 	return isci_request->ttype_ptr.tmf_task_ptr;
269 }
270 
271 #else  /* not ISCI_REQUEST_VALIDATE_ACCESS */
272 
273 #define isci_request_access_task(RequestPtr) \
274 	((RequestPtr)->ttype_ptr.io_task_ptr)
275 
276 #define isci_request_access_tmf(RequestPtr)  \
277 	((RequestPtr)->ttype_ptr.tmf_task_ptr)
278 
279 #endif /* not ISCI_REQUEST_VALIDATE_ACCESS */
280 
281 
282 int isci_request_alloc_tmf(
283 	struct isci_host *isci_host,
284 	struct isci_tmf *isci_tmf,
285 	struct isci_request **isci_request,
286 	struct isci_remote_device *isci_device,
287 	gfp_t gfp_flags);
288 
289 
290 int isci_request_execute(
291 	struct isci_host *isci_host,
292 	struct sas_task *task,
293 	struct isci_request **request,
294 	gfp_t gfp_flags);
295 
296 /**
297  * isci_request_unmap_sgl() - This function unmaps the DMA address of a given
298  *    sgl
299  * @request: This parameter points to the isci_request object
300  * @*pdev: This Parameter is the pci_device struct for the controller
301  *
302  */
303 static inline void isci_request_unmap_sgl(
304 	struct isci_request *request,
305 	struct pci_dev *pdev)
306 {
307 	struct sas_task *task = isci_request_access_task(request);
308 
309 	dev_dbg(&request->isci_host->pdev->dev,
310 		"%s: request = %p, task = %p,\n"
311 		"task->data_dir = %d, is_sata = %d\n ",
312 		__func__,
313 		request,
314 		task,
315 		task->data_dir,
316 		sas_protocol_ata(task->task_proto));
317 
318 	if ((task->data_dir != PCI_DMA_NONE) &&
319 	    !sas_protocol_ata(task->task_proto)) {
320 		if (task->num_scatter == 0)
321 			/* 0 indicates a single dma address */
322 			dma_unmap_single(
323 				&pdev->dev,
324 				request->zero_scatter_daddr,
325 				task->total_xfer_len,
326 				task->data_dir
327 				);
328 
329 		else  /* unmap the sgl dma addresses */
330 			dma_unmap_sg(
331 				&pdev->dev,
332 				task->scatter,
333 				request->num_sg_entries,
334 				task->data_dir
335 				);
336 	}
337 }
338 
339 
340 void isci_request_io_request_complete(
341 	struct isci_host *isci_host,
342 	struct isci_request *request,
343 	enum sci_io_status completion_status);
344 
345 /**
346  * isci_request_io_request_get_next_sge() - This function is called by the sci
347  *    core to retrieve the next sge for a given request.
348  * @request: This parameter is the isci_request object.
349  * @current_sge_address: This parameter is the last sge retrieved by the sci
350  *    core for this request.
351  *
352  * pointer to the next sge for specified request.
353  */
354 static inline void *isci_request_io_request_get_next_sge(
355 	struct isci_request *request,
356 	void *current_sge_address)
357 {
358 	struct sas_task *task = isci_request_access_task(request);
359 	void *ret = NULL;
360 
361 	dev_dbg(&request->isci_host->pdev->dev,
362 		"%s: request = %p, "
363 		"current_sge_address = %p, "
364 		"num_scatter = %d\n",
365 		__func__,
366 		request,
367 		current_sge_address,
368 		task->num_scatter);
369 
370 	if (!current_sge_address)	/* First time through.. */
371 		ret = task->scatter;    /* always task->scatter */
372 	else if (task->num_scatter == 0) /* Next element, if num_scatter == 0 */
373 		ret = NULL;              /* there is only one element. */
374 	else
375 		ret = sg_next(current_sge_address);     /* sg_next returns NULL
376 							 * for the last element
377 							 */
378 
379 	dev_dbg(&request->isci_host->pdev->dev,
380 		"%s: next sge address = %p\n",
381 		__func__,
382 		ret);
383 
384 	return ret;
385 }
386 
387 
388 void isci_terminate_pending_requests(
389 	struct isci_host *isci_host,
390 	struct isci_remote_device *isci_device,
391 	enum isci_request_status new_request_state);
392 
393 
394 
395 
396 #endif /* !defined(_ISCI_REQUEST_H_) */
397