xref: /linux/drivers/scsi/isci/request.h (revision ce2b3261b6765c3b80fda95426c73e8d3bb1b035)
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 "host.h"
61 #include "scic_sds_request.h"
62 
63 /**
64  * struct isci_request_status - This enum defines the possible states of an I/O
65  *    request.
66  *
67  *
68  */
69 enum isci_request_status {
70 	unallocated = 0x00,
71 	allocated   = 0x01,
72 	started     = 0x02,
73 	completed   = 0x03,
74 	aborting    = 0x04,
75 	aborted     = 0x05,
76 	terminating = 0x06,
77 	dead        = 0x07
78 };
79 
80 enum task_type {
81 	io_task  = 0,
82 	tmf_task = 1
83 };
84 
85 struct isci_request {
86 	enum isci_request_status status;
87 	enum task_type ttype;
88 	unsigned short io_tag;
89 	bool complete_in_target;
90 	bool terminated;
91 
92 	union ttype_ptr_union {
93 		struct sas_task *io_task_ptr;   /* When ttype==io_task  */
94 		struct isci_tmf *tmf_task_ptr;  /* When ttype==tmf_task */
95 	} ttype_ptr;
96 	struct isci_host *isci_host;
97 	struct isci_remote_device *isci_device;
98 	/* For use in the requests_to_{complete|abort} lists: */
99 	struct list_head completed_node;
100 	/* For use in the reqs_in_process list: */
101 	struct list_head dev_node;
102 	spinlock_t state_lock;
103 	dma_addr_t request_daddr;
104 	dma_addr_t zero_scatter_daddr;
105 
106 	unsigned int num_sg_entries;                    /* returned by pci_alloc_sg */
107 
108 	/** Note: "io_request_completion" is completed in two different ways
109 	 * depending on whether this is a TMF or regular request.
110 	 * - TMF requests are completed in the thread that started them;
111 	 * - regular requests are completed in the request completion callback
112 	 *   function.
113 	 * This difference in operation allows the aborter of a TMF request
114 	 * to be sure that once the TMF request completes, the I/O that the
115 	 * TMF was aborting is guaranteed to have completed.
116 	 */
117 	struct completion *io_request_completion;
118 	struct scic_sds_request sci;
119 };
120 
121 static inline struct isci_request *sci_req_to_ireq(struct scic_sds_request *sci_req)
122 {
123 	struct isci_request *ireq = container_of(sci_req, typeof(*ireq), sci);
124 
125 	return ireq;
126 }
127 
128 /**
129  * This function gets the status of the request object.
130  * @request: This parameter points to the isci_request object
131  *
132  * status of the object as a isci_request_status enum.
133  */
134 static inline
135 enum isci_request_status isci_request_get_state(
136 	struct isci_request *isci_request)
137 {
138 	BUG_ON(isci_request == NULL);
139 
140 	/*probably a bad sign...	*/
141 	if (isci_request->status == unallocated)
142 		dev_warn(&isci_request->isci_host->pdev->dev,
143 			 "%s: isci_request->status == unallocated\n",
144 			 __func__);
145 
146 	return isci_request->status;
147 }
148 
149 
150 /**
151  * isci_request_change_state() - This function sets the status of the request
152  *    object.
153  * @request: This parameter points to the isci_request object
154  * @status: This Parameter is the new status of the object
155  *
156  */
157 static inline enum isci_request_status isci_request_change_state(
158 	struct isci_request *isci_request,
159 	enum isci_request_status status)
160 {
161 	enum isci_request_status old_state;
162 	unsigned long flags;
163 
164 	dev_dbg(&isci_request->isci_host->pdev->dev,
165 		"%s: isci_request = %p, state = 0x%x\n",
166 		__func__,
167 		isci_request,
168 		status);
169 
170 	BUG_ON(isci_request == NULL);
171 
172 	spin_lock_irqsave(&isci_request->state_lock, flags);
173 	old_state = isci_request->status;
174 	isci_request->status = status;
175 	spin_unlock_irqrestore(&isci_request->state_lock, flags);
176 
177 	return old_state;
178 }
179 
180 /**
181  * isci_request_change_started_to_newstate() - This function sets the status of
182  *    the request object.
183  * @request: This parameter points to the isci_request object
184  * @status: This Parameter is the new status of the object
185  *
186  * state previous to any change.
187  */
188 static inline enum isci_request_status isci_request_change_started_to_newstate(
189 	struct isci_request *isci_request,
190 	struct completion *completion_ptr,
191 	enum isci_request_status newstate)
192 {
193 	enum isci_request_status old_state;
194 	unsigned long flags;
195 
196 	spin_lock_irqsave(&isci_request->state_lock, flags);
197 
198 	old_state = isci_request->status;
199 
200 	if (old_state == started || old_state == aborting) {
201 		BUG_ON(isci_request->io_request_completion != NULL);
202 
203 		isci_request->io_request_completion = completion_ptr;
204 		isci_request->status = newstate;
205 	}
206 	spin_unlock_irqrestore(&isci_request->state_lock, flags);
207 
208 	dev_dbg(&isci_request->isci_host->pdev->dev,
209 		"%s: isci_request = %p, old_state = 0x%x\n",
210 		__func__,
211 		isci_request,
212 		old_state);
213 
214 	return old_state;
215 }
216 
217 /**
218  * isci_request_change_started_to_aborted() - This function sets the status of
219  *    the request object.
220  * @request: This parameter points to the isci_request object
221  * @completion_ptr: This parameter is saved as the kernel completion structure
222  *    signalled when the old request completes.
223  *
224  * state previous to any change.
225  */
226 static inline enum isci_request_status isci_request_change_started_to_aborted(
227 	struct isci_request *isci_request,
228 	struct completion *completion_ptr)
229 {
230 	return isci_request_change_started_to_newstate(
231 		       isci_request, completion_ptr, aborted
232 		       );
233 }
234 /**
235  * isci_request_free() - This function frees the request object.
236  * @isci_host: This parameter specifies the ISCI host object
237  * @isci_request: This parameter points to the isci_request object
238  *
239  */
240 static inline void isci_request_free(
241 	struct isci_host *isci_host,
242 	struct isci_request *isci_request)
243 {
244 	if (!isci_request)
245 		return;
246 
247 	/* release the dma memory if we fail. */
248 	dma_pool_free(isci_host->dma_pool, isci_request,
249 		      isci_request->request_daddr);
250 }
251 
252 
253 /* #define ISCI_REQUEST_VALIDATE_ACCESS
254  */
255 
256 #ifdef ISCI_REQUEST_VALIDATE_ACCESS
257 
258 static inline
259 struct sas_task *isci_request_access_task(struct isci_request *isci_request)
260 {
261 	BUG_ON(isci_request->ttype != io_task);
262 	return isci_request->ttype_ptr.io_task_ptr;
263 }
264 
265 static inline
266 struct isci_tmf *isci_request_access_tmf(struct isci_request *isci_request)
267 {
268 	BUG_ON(isci_request->ttype != tmf_task);
269 	return isci_request->ttype_ptr.tmf_task_ptr;
270 }
271 
272 #else  /* not ISCI_REQUEST_VALIDATE_ACCESS */
273 
274 #define isci_request_access_task(RequestPtr) \
275 	((RequestPtr)->ttype_ptr.io_task_ptr)
276 
277 #define isci_request_access_tmf(RequestPtr)  \
278 	((RequestPtr)->ttype_ptr.tmf_task_ptr)
279 
280 #endif /* not ISCI_REQUEST_VALIDATE_ACCESS */
281 
282 
283 int isci_request_alloc_tmf(
284 	struct isci_host *isci_host,
285 	struct isci_tmf *isci_tmf,
286 	struct isci_request **isci_request,
287 	struct isci_remote_device *isci_device,
288 	gfp_t gfp_flags);
289 
290 
291 int isci_request_execute(
292 	struct isci_host *isci_host,
293 	struct sas_task *task,
294 	struct isci_request **request,
295 	gfp_t gfp_flags);
296 
297 /**
298  * isci_request_unmap_sgl() - This function unmaps the DMA address of a given
299  *    sgl
300  * @request: This parameter points to the isci_request object
301  * @*pdev: This Parameter is the pci_device struct for the controller
302  *
303  */
304 static inline void isci_request_unmap_sgl(
305 	struct isci_request *request,
306 	struct pci_dev *pdev)
307 {
308 	struct sas_task *task = isci_request_access_task(request);
309 
310 	dev_dbg(&request->isci_host->pdev->dev,
311 		"%s: request = %p, task = %p,\n"
312 		"task->data_dir = %d, is_sata = %d\n ",
313 		__func__,
314 		request,
315 		task,
316 		task->data_dir,
317 		sas_protocol_ata(task->task_proto));
318 
319 	if ((task->data_dir != PCI_DMA_NONE) &&
320 	    !sas_protocol_ata(task->task_proto)) {
321 		if (task->num_scatter == 0)
322 			/* 0 indicates a single dma address */
323 			dma_unmap_single(
324 				&pdev->dev,
325 				request->zero_scatter_daddr,
326 				task->total_xfer_len,
327 				task->data_dir
328 				);
329 
330 		else  /* unmap the sgl dma addresses */
331 			dma_unmap_sg(
332 				&pdev->dev,
333 				task->scatter,
334 				request->num_sg_entries,
335 				task->data_dir
336 				);
337 	}
338 }
339 
340 
341 void isci_request_io_request_complete(
342 	struct isci_host *isci_host,
343 	struct isci_request *request,
344 	enum sci_io_status completion_status);
345 
346 /**
347  * isci_request_io_request_get_next_sge() - This function is called by the sci
348  *    core to retrieve the next sge for a given request.
349  * @request: This parameter is the isci_request object.
350  * @current_sge_address: This parameter is the last sge retrieved by the sci
351  *    core for this request.
352  *
353  * pointer to the next sge for specified request.
354  */
355 static inline void *isci_request_io_request_get_next_sge(
356 	struct isci_request *request,
357 	void *current_sge_address)
358 {
359 	struct sas_task *task = isci_request_access_task(request);
360 	void *ret = NULL;
361 
362 	dev_dbg(&request->isci_host->pdev->dev,
363 		"%s: request = %p, "
364 		"current_sge_address = %p, "
365 		"num_scatter = %d\n",
366 		__func__,
367 		request,
368 		current_sge_address,
369 		task->num_scatter);
370 
371 	if (!current_sge_address)	/* First time through.. */
372 		ret = task->scatter;    /* always task->scatter */
373 	else if (task->num_scatter == 0) /* Next element, if num_scatter == 0 */
374 		ret = NULL;              /* there is only one element. */
375 	else
376 		ret = sg_next(current_sge_address);     /* sg_next returns NULL
377 							 * for the last element
378 							 */
379 
380 	dev_dbg(&request->isci_host->pdev->dev,
381 		"%s: next sge address = %p\n",
382 		__func__,
383 		ret);
384 
385 	return ret;
386 }
387 
388 
389 void isci_terminate_pending_requests(
390 	struct isci_host *isci_host,
391 	struct isci_remote_device *isci_device,
392 	enum isci_request_status new_request_state);
393 
394 
395 
396 
397 #endif /* !defined(_ISCI_REQUEST_H_) */
398