xref: /openbmc/linux/drivers/scsi/isci/request.h (revision 0d84366fbef557f92ef82ac9a224c57ffb3318bc)
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
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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 	struct scic_sds_request *sci_request_handle;
86 	enum isci_request_status status;
87 	enum task_type ttype;
88 	unsigned short io_tag;
89 	bool complete_in_target;
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 	unsigned int request_alloc_size;                /* size of block from dma_pool_alloc */
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_req[0] ____cacheline_aligned;
119 };
120 
121 /**
122  * This function gets the status of the request object.
123  * @request: This parameter points to the isci_request object
124  *
125  * status of the object as a isci_request_status enum.
126  */
127 static inline
128 enum isci_request_status isci_request_get_state(
129 	struct isci_request *isci_request)
130 {
131 	BUG_ON(isci_request == NULL);
132 
133 	/*probably a bad sign...	*/
134 	if (isci_request->status == unallocated)
135 		dev_warn(&isci_request->isci_host->pdev->dev,
136 			 "%s: isci_request->status == unallocated\n",
137 			 __func__);
138 
139 	return isci_request->status;
140 }
141 
142 
143 /**
144  * isci_request_change_state() - This function sets the status of the request
145  *    object.
146  * @request: This parameter points to the isci_request object
147  * @status: This Parameter is the new status of the object
148  *
149  */
150 static inline enum isci_request_status isci_request_change_state(
151 	struct isci_request *isci_request,
152 	enum isci_request_status status)
153 {
154 	enum isci_request_status old_state;
155 	unsigned long flags;
156 
157 	dev_dbg(&isci_request->isci_host->pdev->dev,
158 		"%s: isci_request = %p, state = 0x%x\n",
159 		__func__,
160 		isci_request,
161 		status);
162 
163 	BUG_ON(isci_request == NULL);
164 
165 	spin_lock_irqsave(&isci_request->state_lock, flags);
166 	old_state = isci_request->status;
167 	isci_request->status = status;
168 	spin_unlock_irqrestore(&isci_request->state_lock, flags);
169 
170 	return old_state;
171 }
172 
173 /**
174  * isci_request_change_started_to_newstate() - This function sets the status of
175  *    the request object.
176  * @request: This parameter points to the isci_request object
177  * @status: This Parameter is the new status of the object
178  *
179  * state previous to any change.
180  */
181 static inline enum isci_request_status isci_request_change_started_to_newstate(
182 	struct isci_request *isci_request,
183 	struct completion *completion_ptr,
184 	enum isci_request_status newstate)
185 {
186 	enum isci_request_status old_state;
187 	unsigned long flags;
188 
189 	spin_lock_irqsave(&isci_request->state_lock, flags);
190 
191 	old_state = isci_request->status;
192 
193 	if (old_state == started || old_state == aborting) {
194 		BUG_ON(isci_request->io_request_completion != NULL);
195 
196 		isci_request->io_request_completion = completion_ptr;
197 		isci_request->status = newstate;
198 	}
199 	spin_unlock_irqrestore(&isci_request->state_lock, flags);
200 
201 	dev_dbg(&isci_request->isci_host->pdev->dev,
202 		"%s: isci_request = %p, old_state = 0x%x\n",
203 		__func__,
204 		isci_request,
205 		old_state);
206 
207 	return old_state;
208 }
209 
210 /**
211  * isci_request_change_started_to_aborted() - This function sets the status of
212  *    the request object.
213  * @request: This parameter points to the isci_request object
214  * @completion_ptr: This parameter is saved as the kernel completion structure
215  *    signalled when the old request completes.
216  *
217  * state previous to any change.
218  */
219 static inline enum isci_request_status isci_request_change_started_to_aborted(
220 	struct isci_request *isci_request,
221 	struct completion *completion_ptr)
222 {
223 	return isci_request_change_started_to_newstate(
224 		       isci_request, completion_ptr, aborted
225 		       );
226 }
227 /**
228  * isci_request_free() - This function frees the request object.
229  * @isci_host: This parameter specifies the ISCI host object
230  * @isci_request: This parameter points to the isci_request object
231  *
232  */
233 static inline void isci_request_free(
234 	struct isci_host *isci_host,
235 	struct isci_request *isci_request)
236 {
237 	if (!isci_request)
238 		return;
239 
240 	/* release the dma memory if we fail. */
241 	dma_pool_free(isci_host->dma_pool, isci_request,
242 		      isci_request->request_daddr);
243 }
244 
245 
246 /* #define ISCI_REQUEST_VALIDATE_ACCESS
247  */
248 
249 #ifdef ISCI_REQUEST_VALIDATE_ACCESS
250 
251 static inline
252 struct sas_task *isci_request_access_task(struct isci_request *isci_request)
253 {
254 	BUG_ON(isci_request->ttype != io_task);
255 	return isci_request->ttype_ptr.io_task_ptr;
256 }
257 
258 static inline
259 struct isci_tmf *isci_request_access_tmf(struct isci_request *isci_request)
260 {
261 	BUG_ON(isci_request->ttype != tmf_task);
262 	return isci_request->ttype_ptr.tmf_task_ptr;
263 }
264 
265 #else  /* not ISCI_REQUEST_VALIDATE_ACCESS */
266 
267 #define isci_request_access_task(RequestPtr) \
268 	((RequestPtr)->ttype_ptr.io_task_ptr)
269 
270 #define isci_request_access_tmf(RequestPtr)  \
271 	((RequestPtr)->ttype_ptr.tmf_task_ptr)
272 
273 #endif /* not ISCI_REQUEST_VALIDATE_ACCESS */
274 
275 
276 int isci_request_alloc_tmf(
277 	struct isci_host *isci_host,
278 	struct isci_tmf *isci_tmf,
279 	struct isci_request **isci_request,
280 	struct isci_remote_device *isci_device,
281 	gfp_t gfp_flags);
282 
283 
284 int isci_request_execute(
285 	struct isci_host *isci_host,
286 	struct sas_task *task,
287 	struct isci_request **request,
288 	gfp_t gfp_flags);
289 
290 /**
291  * isci_request_unmap_sgl() - This function unmaps the DMA address of a given
292  *    sgl
293  * @request: This parameter points to the isci_request object
294  * @*pdev: This Parameter is the pci_device struct for the controller
295  *
296  */
297 static inline void isci_request_unmap_sgl(
298 	struct isci_request *request,
299 	struct pci_dev *pdev)
300 {
301 	struct sas_task *task = isci_request_access_task(request);
302 
303 	dev_dbg(&request->isci_host->pdev->dev,
304 		"%s: request = %p, task = %p,\n"
305 		"task->data_dir = %d, is_sata = %d\n ",
306 		__func__,
307 		request,
308 		task,
309 		task->data_dir,
310 		sas_protocol_ata(task->task_proto));
311 
312 	if ((task->data_dir != PCI_DMA_NONE) &&
313 	    !sas_protocol_ata(task->task_proto)) {
314 		if (task->num_scatter == 0)
315 			/* 0 indicates a single dma address */
316 			dma_unmap_single(
317 				&pdev->dev,
318 				request->zero_scatter_daddr,
319 				task->total_xfer_len,
320 				task->data_dir
321 				);
322 
323 		else  /* unmap the sgl dma addresses */
324 			dma_unmap_sg(
325 				&pdev->dev,
326 				task->scatter,
327 				request->num_sg_entries,
328 				task->data_dir
329 				);
330 	}
331 }
332 
333 
334 void isci_request_io_request_complete(
335 	struct isci_host *isci_host,
336 	struct isci_request *request,
337 	enum sci_io_status completion_status);
338 
339 /**
340  * isci_request_io_request_get_next_sge() - This function is called by the sci
341  *    core to retrieve the next sge for a given request.
342  * @request: This parameter is the isci_request object.
343  * @current_sge_address: This parameter is the last sge retrieved by the sci
344  *    core for this request.
345  *
346  * pointer to the next sge for specified request.
347  */
348 static inline void *isci_request_io_request_get_next_sge(
349 	struct isci_request *request,
350 	void *current_sge_address)
351 {
352 	struct sas_task *task = isci_request_access_task(request);
353 	void *ret = NULL;
354 
355 	dev_dbg(&request->isci_host->pdev->dev,
356 		"%s: request = %p, "
357 		"current_sge_address = %p, "
358 		"num_scatter = %d\n",
359 		__func__,
360 		request,
361 		current_sge_address,
362 		task->num_scatter);
363 
364 	if (!current_sge_address)	/* First time through.. */
365 		ret = task->scatter;    /* always task->scatter */
366 	else if (task->num_scatter == 0) /* Next element, if num_scatter == 0 */
367 		ret = NULL;              /* there is only one element. */
368 	else
369 		ret = sg_next(current_sge_address);     /* sg_next returns NULL
370 							 * for the last element
371 							 */
372 
373 	dev_dbg(&request->isci_host->pdev->dev,
374 		"%s: next sge address = %p\n",
375 		__func__,
376 		ret);
377 
378 	return ret;
379 }
380 
381 
382 void isci_terminate_pending_requests(
383 	struct isci_host *isci_host,
384 	struct isci_remote_device *isci_device,
385 	enum isci_request_status new_request_state);
386 
387 
388 
389 
390 #endif /* !defined(_ISCI_REQUEST_H_) */
391