1 /*
2  *  Linux MegaRAID driver for SAS based RAID controllers
3  *
4  *  Copyright (c) 2009-2013  LSI Corporation
5  *  Copyright (c) 2013-2014  Avago Technologies
6  *
7  *  This program is free software; you can redistribute it and/or
8  *  modify it under the terms of the GNU General Public License
9  *  as published by the Free Software Foundation; either version 2
10  *  of the License, or (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
19  *
20  *  FILE: megaraid_sas_fp.c
21  *
22  *  Authors: Avago Technologies
23  *           Sumant Patro
24  *           Varad Talamacki
25  *           Manoj Jose
26  *           Kashyap Desai <kashyap.desai@avagotech.com>
27  *           Sumit Saxena <sumit.saxena@avagotech.com>
28  *
29  *  Send feedback to: megaraidlinux.pdl@avagotech.com
30  *
31  *  Mail to: Avago Technologies, 350 West Trimble Road, Building 90,
32  *  San Jose, California 95131
33  */
34 
35 #include <linux/kernel.h>
36 #include <linux/types.h>
37 #include <linux/pci.h>
38 #include <linux/list.h>
39 #include <linux/moduleparam.h>
40 #include <linux/module.h>
41 #include <linux/spinlock.h>
42 #include <linux/interrupt.h>
43 #include <linux/delay.h>
44 #include <linux/uio.h>
45 #include <linux/uaccess.h>
46 #include <linux/fs.h>
47 #include <linux/compat.h>
48 #include <linux/blkdev.h>
49 #include <linux/poll.h>
50 
51 #include <scsi/scsi.h>
52 #include <scsi/scsi_cmnd.h>
53 #include <scsi/scsi_device.h>
54 #include <scsi/scsi_host.h>
55 
56 #include "megaraid_sas_fusion.h"
57 #include "megaraid_sas.h"
58 #include <asm/div64.h>
59 
60 #define LB_PENDING_CMDS_DEFAULT 4
61 static unsigned int lb_pending_cmds = LB_PENDING_CMDS_DEFAULT;
62 module_param(lb_pending_cmds, int, S_IRUGO);
63 MODULE_PARM_DESC(lb_pending_cmds, "Change raid-1 load balancing outstanding "
64 	"threshold. Valid Values are 1-128. Default: 4");
65 
66 
67 #define ABS_DIFF(a, b)   (((a) > (b)) ? ((a) - (b)) : ((b) - (a)))
68 #define MR_LD_STATE_OPTIMAL 3
69 
70 #define SPAN_ROW_SIZE(map, ld, index_) (MR_LdSpanPtrGet(ld, index_, map)->spanRowSize)
71 #define SPAN_ROW_DATA_SIZE(map_, ld, index_)   (MR_LdSpanPtrGet(ld, index_, map)->spanRowDataSize)
72 #define SPAN_INVALID  0xff
73 
74 /* Prototypes */
75 static void mr_update_span_set(struct MR_DRV_RAID_MAP_ALL *map,
76 	PLD_SPAN_INFO ldSpanInfo);
77 static u8 mr_spanset_get_phy_params(struct megasas_instance *instance, u32 ld,
78 	u64 stripRow, u16 stripRef, struct IO_REQUEST_INFO *io_info,
79 	struct RAID_CONTEXT *pRAID_Context, struct MR_DRV_RAID_MAP_ALL *map);
80 static u64 get_row_from_strip(struct megasas_instance *instance, u32 ld,
81 	u64 strip, struct MR_DRV_RAID_MAP_ALL *map);
82 
83 u32 mega_mod64(u64 dividend, u32 divisor)
84 {
85 	u64 d;
86 	u32 remainder;
87 
88 	if (!divisor)
89 		printk(KERN_ERR "megasas : DIVISOR is zero, in div fn\n");
90 	d = dividend;
91 	remainder = do_div(d, divisor);
92 	return remainder;
93 }
94 
95 /**
96  * @param dividend    : Dividend
97  * @param divisor    : Divisor
98  *
99  * @return quotient
100  **/
101 u64 mega_div64_32(uint64_t dividend, uint32_t divisor)
102 {
103 	u32 remainder;
104 	u64 d;
105 
106 	if (!divisor)
107 		printk(KERN_ERR "megasas : DIVISOR is zero in mod fn\n");
108 
109 	d = dividend;
110 	remainder = do_div(d, divisor);
111 
112 	return d;
113 }
114 
115 struct MR_LD_RAID *MR_LdRaidGet(u32 ld, struct MR_DRV_RAID_MAP_ALL *map)
116 {
117 	return &map->raidMap.ldSpanMap[ld].ldRaid;
118 }
119 
120 static struct MR_SPAN_BLOCK_INFO *MR_LdSpanInfoGet(u32 ld,
121 						   struct MR_DRV_RAID_MAP_ALL
122 						   *map)
123 {
124 	return &map->raidMap.ldSpanMap[ld].spanBlock[0];
125 }
126 
127 static u8 MR_LdDataArmGet(u32 ld, u32 armIdx, struct MR_DRV_RAID_MAP_ALL *map)
128 {
129 	return map->raidMap.ldSpanMap[ld].dataArmMap[armIdx];
130 }
131 
132 u16 MR_ArPdGet(u32 ar, u32 arm, struct MR_DRV_RAID_MAP_ALL *map)
133 {
134 	return le16_to_cpu(map->raidMap.arMapInfo[ar].pd[arm]);
135 }
136 
137 u16 MR_LdSpanArrayGet(u32 ld, u32 span, struct MR_DRV_RAID_MAP_ALL *map)
138 {
139 	return le16_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].span.arrayRef);
140 }
141 
142 __le16 MR_PdDevHandleGet(u32 pd, struct MR_DRV_RAID_MAP_ALL *map)
143 {
144 	return map->raidMap.devHndlInfo[pd].curDevHdl;
145 }
146 
147 static u8 MR_PdInterfaceTypeGet(u32 pd, struct MR_DRV_RAID_MAP_ALL *map)
148 {
149 	return map->raidMap.devHndlInfo[pd].interfaceType;
150 }
151 
152 u16 MR_GetLDTgtId(u32 ld, struct MR_DRV_RAID_MAP_ALL *map)
153 {
154 	return le16_to_cpu(map->raidMap.ldSpanMap[ld].ldRaid.targetId);
155 }
156 
157 u16 MR_TargetIdToLdGet(u32 ldTgtId, struct MR_DRV_RAID_MAP_ALL *map)
158 {
159 	return map->raidMap.ldTgtIdToLd[ldTgtId];
160 }
161 
162 static struct MR_LD_SPAN *MR_LdSpanPtrGet(u32 ld, u32 span,
163 					  struct MR_DRV_RAID_MAP_ALL *map)
164 {
165 	return &map->raidMap.ldSpanMap[ld].spanBlock[span].span;
166 }
167 
168 /*
169  * This function will Populate Driver Map using firmware raid map
170  */
171 void MR_PopulateDrvRaidMap(struct megasas_instance *instance)
172 {
173 	struct fusion_context *fusion = instance->ctrl_context;
174 	struct MR_FW_RAID_MAP_ALL     *fw_map_old    = NULL;
175 	struct MR_FW_RAID_MAP         *pFwRaidMap    = NULL;
176 	int i, j;
177 	u16 ld_count;
178 	struct MR_FW_RAID_MAP_DYNAMIC *fw_map_dyn;
179 	struct MR_FW_RAID_MAP_EXT *fw_map_ext;
180 	struct MR_RAID_MAP_DESC_TABLE *desc_table;
181 
182 
183 	struct MR_DRV_RAID_MAP_ALL *drv_map =
184 			fusion->ld_drv_map[(instance->map_id & 1)];
185 	struct MR_DRV_RAID_MAP *pDrvRaidMap = &drv_map->raidMap;
186 	void *raid_map_data = NULL;
187 
188 	memset(drv_map, 0, fusion->drv_map_sz);
189 	memset(pDrvRaidMap->ldTgtIdToLd,
190 	       0xff, (sizeof(u16) * MAX_LOGICAL_DRIVES_DYN));
191 
192 	if (instance->max_raid_mapsize) {
193 		fw_map_dyn = fusion->ld_map[(instance->map_id & 1)];
194 		desc_table =
195 		(struct MR_RAID_MAP_DESC_TABLE *)((void *)fw_map_dyn + le32_to_cpu(fw_map_dyn->desc_table_offset));
196 		if (desc_table != fw_map_dyn->raid_map_desc_table)
197 			dev_dbg(&instance->pdev->dev, "offsets of desc table are not matching desc %p original %p\n",
198 				desc_table, fw_map_dyn->raid_map_desc_table);
199 
200 		ld_count = (u16)le16_to_cpu(fw_map_dyn->ld_count);
201 		pDrvRaidMap->ldCount = (__le16)cpu_to_le16(ld_count);
202 		pDrvRaidMap->fpPdIoTimeoutSec =
203 			fw_map_dyn->fp_pd_io_timeout_sec;
204 		pDrvRaidMap->totalSize =
205 			cpu_to_le32(sizeof(struct MR_DRV_RAID_MAP_ALL));
206 		/* point to actual data starting point*/
207 		raid_map_data = (void *)fw_map_dyn +
208 			le32_to_cpu(fw_map_dyn->desc_table_offset) +
209 			le32_to_cpu(fw_map_dyn->desc_table_size);
210 
211 		for (i = 0; i < le32_to_cpu(fw_map_dyn->desc_table_num_elements); ++i) {
212 			switch (le32_to_cpu(desc_table->raid_map_desc_type)) {
213 			case RAID_MAP_DESC_TYPE_DEVHDL_INFO:
214 				fw_map_dyn->dev_hndl_info =
215 				(struct MR_DEV_HANDLE_INFO *)(raid_map_data + le32_to_cpu(desc_table->raid_map_desc_offset));
216 				memcpy(pDrvRaidMap->devHndlInfo,
217 					fw_map_dyn->dev_hndl_info,
218 					sizeof(struct MR_DEV_HANDLE_INFO) *
219 					le32_to_cpu(desc_table->raid_map_desc_elements));
220 			break;
221 			case RAID_MAP_DESC_TYPE_TGTID_INFO:
222 				fw_map_dyn->ld_tgt_id_to_ld =
223 					(u16 *)(raid_map_data +
224 					le32_to_cpu(desc_table->raid_map_desc_offset));
225 				for (j = 0; j < le32_to_cpu(desc_table->raid_map_desc_elements); j++) {
226 					pDrvRaidMap->ldTgtIdToLd[j] =
227 						le16_to_cpu(fw_map_dyn->ld_tgt_id_to_ld[j]);
228 				}
229 			break;
230 			case RAID_MAP_DESC_TYPE_ARRAY_INFO:
231 				fw_map_dyn->ar_map_info =
232 					(struct MR_ARRAY_INFO *)
233 					(raid_map_data + le32_to_cpu(desc_table->raid_map_desc_offset));
234 				memcpy(pDrvRaidMap->arMapInfo,
235 				       fw_map_dyn->ar_map_info,
236 				       sizeof(struct MR_ARRAY_INFO) *
237 				       le32_to_cpu(desc_table->raid_map_desc_elements));
238 			break;
239 			case RAID_MAP_DESC_TYPE_SPAN_INFO:
240 				fw_map_dyn->ld_span_map =
241 					(struct MR_LD_SPAN_MAP *)
242 					(raid_map_data +
243 					le32_to_cpu(desc_table->raid_map_desc_offset));
244 				memcpy(pDrvRaidMap->ldSpanMap,
245 				       fw_map_dyn->ld_span_map,
246 				       sizeof(struct MR_LD_SPAN_MAP) *
247 				       le32_to_cpu(desc_table->raid_map_desc_elements));
248 			break;
249 			default:
250 				dev_dbg(&instance->pdev->dev, "wrong number of desctableElements %d\n",
251 					fw_map_dyn->desc_table_num_elements);
252 			}
253 			++desc_table;
254 		}
255 
256 	} else if (instance->supportmax256vd) {
257 		fw_map_ext =
258 			(struct MR_FW_RAID_MAP_EXT *)fusion->ld_map[(instance->map_id & 1)];
259 		ld_count = (u16)le16_to_cpu(fw_map_ext->ldCount);
260 		if (ld_count > MAX_LOGICAL_DRIVES_EXT) {
261 			dev_dbg(&instance->pdev->dev, "megaraid_sas: LD count exposed in RAID map in not valid\n");
262 			return;
263 		}
264 
265 		pDrvRaidMap->ldCount = (__le16)cpu_to_le16(ld_count);
266 		pDrvRaidMap->fpPdIoTimeoutSec = fw_map_ext->fpPdIoTimeoutSec;
267 		for (i = 0; i < (MAX_LOGICAL_DRIVES_EXT); i++)
268 			pDrvRaidMap->ldTgtIdToLd[i] =
269 				(u16)fw_map_ext->ldTgtIdToLd[i];
270 		memcpy(pDrvRaidMap->ldSpanMap, fw_map_ext->ldSpanMap,
271 		       sizeof(struct MR_LD_SPAN_MAP) * ld_count);
272 		memcpy(pDrvRaidMap->arMapInfo, fw_map_ext->arMapInfo,
273 		       sizeof(struct MR_ARRAY_INFO) * MAX_API_ARRAYS_EXT);
274 		memcpy(pDrvRaidMap->devHndlInfo, fw_map_ext->devHndlInfo,
275 		       sizeof(struct MR_DEV_HANDLE_INFO) *
276 		       MAX_RAIDMAP_PHYSICAL_DEVICES);
277 
278 		/* New Raid map will not set totalSize, so keep expected value
279 		 * for legacy code in ValidateMapInfo
280 		 */
281 		pDrvRaidMap->totalSize =
282 			cpu_to_le32(sizeof(struct MR_FW_RAID_MAP_EXT));
283 	} else {
284 		fw_map_old = (struct MR_FW_RAID_MAP_ALL *)
285 			fusion->ld_map[(instance->map_id & 1)];
286 		pFwRaidMap = &fw_map_old->raidMap;
287 		ld_count = (u16)le32_to_cpu(pFwRaidMap->ldCount);
288 		pDrvRaidMap->totalSize = pFwRaidMap->totalSize;
289 		pDrvRaidMap->ldCount = (__le16)cpu_to_le16(ld_count);
290 		pDrvRaidMap->fpPdIoTimeoutSec = pFwRaidMap->fpPdIoTimeoutSec;
291 		for (i = 0; i < MAX_RAIDMAP_LOGICAL_DRIVES + MAX_RAIDMAP_VIEWS; i++)
292 			pDrvRaidMap->ldTgtIdToLd[i] =
293 				(u8)pFwRaidMap->ldTgtIdToLd[i];
294 		for (i = 0; i < ld_count; i++) {
295 			pDrvRaidMap->ldSpanMap[i] = pFwRaidMap->ldSpanMap[i];
296 		}
297 		memcpy(pDrvRaidMap->arMapInfo, pFwRaidMap->arMapInfo,
298 			sizeof(struct MR_ARRAY_INFO) * MAX_RAIDMAP_ARRAYS);
299 		memcpy(pDrvRaidMap->devHndlInfo, pFwRaidMap->devHndlInfo,
300 			sizeof(struct MR_DEV_HANDLE_INFO) *
301 			MAX_RAIDMAP_PHYSICAL_DEVICES);
302 	}
303 }
304 
305 /*
306  * This function will validate Map info data provided by FW
307  */
308 u8 MR_ValidateMapInfo(struct megasas_instance *instance)
309 {
310 	struct fusion_context *fusion;
311 	struct MR_DRV_RAID_MAP_ALL *drv_map;
312 	struct MR_DRV_RAID_MAP *pDrvRaidMap;
313 	struct LD_LOAD_BALANCE_INFO *lbInfo;
314 	PLD_SPAN_INFO ldSpanInfo;
315 	struct MR_LD_RAID         *raid;
316 	u16 num_lds, i;
317 	u16 ld;
318 	u32 expected_size;
319 
320 
321 	MR_PopulateDrvRaidMap(instance);
322 
323 	fusion = instance->ctrl_context;
324 	drv_map = fusion->ld_drv_map[(instance->map_id & 1)];
325 	pDrvRaidMap = &drv_map->raidMap;
326 
327 	lbInfo = fusion->load_balance_info;
328 	ldSpanInfo = fusion->log_to_span;
329 
330 	if (instance->max_raid_mapsize)
331 		expected_size = sizeof(struct MR_DRV_RAID_MAP_ALL);
332 	else if (instance->supportmax256vd)
333 		expected_size = sizeof(struct MR_FW_RAID_MAP_EXT);
334 	else
335 		expected_size =
336 			(sizeof(struct MR_FW_RAID_MAP) - sizeof(struct MR_LD_SPAN_MAP) +
337 			(sizeof(struct MR_LD_SPAN_MAP) * le16_to_cpu(pDrvRaidMap->ldCount)));
338 
339 	if (le32_to_cpu(pDrvRaidMap->totalSize) != expected_size) {
340 		dev_dbg(&instance->pdev->dev, "megasas: map info structure size 0x%x",
341 			le32_to_cpu(pDrvRaidMap->totalSize));
342 		dev_dbg(&instance->pdev->dev, "is not matching expected size 0x%x\n",
343 			(unsigned int)expected_size);
344 		dev_err(&instance->pdev->dev, "megasas: span map %x, pDrvRaidMap->totalSize : %x\n",
345 			(unsigned int)sizeof(struct MR_LD_SPAN_MAP),
346 			le32_to_cpu(pDrvRaidMap->totalSize));
347 		return 0;
348 	}
349 
350 	if (instance->UnevenSpanSupport)
351 		mr_update_span_set(drv_map, ldSpanInfo);
352 
353 	if (lbInfo)
354 		mr_update_load_balance_params(drv_map, lbInfo);
355 
356 	num_lds = le16_to_cpu(drv_map->raidMap.ldCount);
357 
358 	/*Convert Raid capability values to CPU arch */
359 	for (i = 0; (num_lds > 0) && (i < MAX_LOGICAL_DRIVES_EXT); i++) {
360 		ld = MR_TargetIdToLdGet(i, drv_map);
361 
362 		/* For non existing VDs, iterate to next VD*/
363 		if (ld >= (MAX_LOGICAL_DRIVES_EXT - 1))
364 			continue;
365 
366 		raid = MR_LdRaidGet(ld, drv_map);
367 		le32_to_cpus((u32 *)&raid->capability);
368 
369 		num_lds--;
370 	}
371 
372 	return 1;
373 }
374 
375 u32 MR_GetSpanBlock(u32 ld, u64 row, u64 *span_blk,
376 		    struct MR_DRV_RAID_MAP_ALL *map)
377 {
378 	struct MR_SPAN_BLOCK_INFO *pSpanBlock = MR_LdSpanInfoGet(ld, map);
379 	struct MR_QUAD_ELEMENT    *quad;
380 	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
381 	u32                span, j;
382 
383 	for (span = 0; span < raid->spanDepth; span++, pSpanBlock++) {
384 
385 		for (j = 0; j < le32_to_cpu(pSpanBlock->block_span_info.noElements); j++) {
386 			quad = &pSpanBlock->block_span_info.quad[j];
387 
388 			if (le32_to_cpu(quad->diff) == 0)
389 				return SPAN_INVALID;
390 			if (le64_to_cpu(quad->logStart) <= row && row <=
391 				le64_to_cpu(quad->logEnd) && (mega_mod64(row - le64_to_cpu(quad->logStart),
392 				le32_to_cpu(quad->diff))) == 0) {
393 				if (span_blk != NULL) {
394 					u64  blk, debugBlk;
395 					blk =  mega_div64_32((row-le64_to_cpu(quad->logStart)), le32_to_cpu(quad->diff));
396 					debugBlk = blk;
397 
398 					blk = (blk + le64_to_cpu(quad->offsetInSpan)) << raid->stripeShift;
399 					*span_blk = blk;
400 				}
401 				return span;
402 			}
403 		}
404 	}
405 	return SPAN_INVALID;
406 }
407 
408 /*
409 ******************************************************************************
410 *
411 * This routine calculates the Span block for given row using spanset.
412 *
413 * Inputs :
414 *    instance - HBA instance
415 *    ld   - Logical drive number
416 *    row        - Row number
417 *    map    - LD map
418 *
419 * Outputs :
420 *
421 *    span          - Span number
422 *    block         - Absolute Block number in the physical disk
423 *    div_error	   - Devide error code.
424 */
425 
426 u32 mr_spanset_get_span_block(struct megasas_instance *instance,
427 		u32 ld, u64 row, u64 *span_blk, struct MR_DRV_RAID_MAP_ALL *map)
428 {
429 	struct fusion_context *fusion = instance->ctrl_context;
430 	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
431 	LD_SPAN_SET *span_set;
432 	struct MR_QUAD_ELEMENT    *quad;
433 	u32    span, info;
434 	PLD_SPAN_INFO ldSpanInfo = fusion->log_to_span;
435 
436 	for (info = 0; info < MAX_QUAD_DEPTH; info++) {
437 		span_set = &(ldSpanInfo[ld].span_set[info]);
438 
439 		if (span_set->span_row_data_width == 0)
440 			break;
441 
442 		if (row > span_set->data_row_end)
443 			continue;
444 
445 		for (span = 0; span < raid->spanDepth; span++)
446 			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
447 				block_span_info.noElements) >= info+1) {
448 				quad = &map->raidMap.ldSpanMap[ld].
449 					spanBlock[span].
450 					block_span_info.quad[info];
451 				if (le32_to_cpu(quad->diff) == 0)
452 					return SPAN_INVALID;
453 				if (le64_to_cpu(quad->logStart) <= row  &&
454 					row <= le64_to_cpu(quad->logEnd)  &&
455 					(mega_mod64(row - le64_to_cpu(quad->logStart),
456 						le32_to_cpu(quad->diff))) == 0) {
457 					if (span_blk != NULL) {
458 						u64  blk;
459 						blk = mega_div64_32
460 						    ((row - le64_to_cpu(quad->logStart)),
461 						    le32_to_cpu(quad->diff));
462 						blk = (blk + le64_to_cpu(quad->offsetInSpan))
463 							 << raid->stripeShift;
464 						*span_blk = blk;
465 					}
466 					return span;
467 				}
468 			}
469 	}
470 	return SPAN_INVALID;
471 }
472 
473 /*
474 ******************************************************************************
475 *
476 * This routine calculates the row for given strip using spanset.
477 *
478 * Inputs :
479 *    instance - HBA instance
480 *    ld   - Logical drive number
481 *    Strip        - Strip
482 *    map    - LD map
483 *
484 * Outputs :
485 *
486 *    row         - row associated with strip
487 */
488 
489 static u64  get_row_from_strip(struct megasas_instance *instance,
490 	u32 ld, u64 strip, struct MR_DRV_RAID_MAP_ALL *map)
491 {
492 	struct fusion_context *fusion = instance->ctrl_context;
493 	struct MR_LD_RAID	*raid = MR_LdRaidGet(ld, map);
494 	LD_SPAN_SET	*span_set;
495 	PLD_SPAN_INFO	ldSpanInfo = fusion->log_to_span;
496 	u32		info, strip_offset, span, span_offset;
497 	u64		span_set_Strip, span_set_Row, retval;
498 
499 	for (info = 0; info < MAX_QUAD_DEPTH; info++) {
500 		span_set = &(ldSpanInfo[ld].span_set[info]);
501 
502 		if (span_set->span_row_data_width == 0)
503 			break;
504 		if (strip > span_set->data_strip_end)
505 			continue;
506 
507 		span_set_Strip = strip - span_set->data_strip_start;
508 		strip_offset = mega_mod64(span_set_Strip,
509 				span_set->span_row_data_width);
510 		span_set_Row = mega_div64_32(span_set_Strip,
511 				span_set->span_row_data_width) * span_set->diff;
512 		for (span = 0, span_offset = 0; span < raid->spanDepth; span++)
513 			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
514 				block_span_info.noElements) >= info+1) {
515 				if (strip_offset >=
516 					span_set->strip_offset[span])
517 					span_offset++;
518 				else
519 					break;
520 			}
521 
522 		retval = (span_set->data_row_start + span_set_Row +
523 				(span_offset - 1));
524 		return retval;
525 	}
526 	return -1LLU;
527 }
528 
529 
530 /*
531 ******************************************************************************
532 *
533 * This routine calculates the Start Strip for given row using spanset.
534 *
535 * Inputs :
536 *    instance - HBA instance
537 *    ld   - Logical drive number
538 *    row        - Row number
539 *    map    - LD map
540 *
541 * Outputs :
542 *
543 *    Strip         - Start strip associated with row
544 */
545 
546 static u64 get_strip_from_row(struct megasas_instance *instance,
547 		u32 ld, u64 row, struct MR_DRV_RAID_MAP_ALL *map)
548 {
549 	struct fusion_context *fusion = instance->ctrl_context;
550 	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
551 	LD_SPAN_SET *span_set;
552 	struct MR_QUAD_ELEMENT    *quad;
553 	PLD_SPAN_INFO ldSpanInfo = fusion->log_to_span;
554 	u32    span, info;
555 	u64  strip;
556 
557 	for (info = 0; info < MAX_QUAD_DEPTH; info++) {
558 		span_set = &(ldSpanInfo[ld].span_set[info]);
559 
560 		if (span_set->span_row_data_width == 0)
561 			break;
562 		if (row > span_set->data_row_end)
563 			continue;
564 
565 		for (span = 0; span < raid->spanDepth; span++)
566 			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
567 				block_span_info.noElements) >= info+1) {
568 				quad = &map->raidMap.ldSpanMap[ld].
569 					spanBlock[span].block_span_info.quad[info];
570 				if (le64_to_cpu(quad->logStart) <= row  &&
571 					row <= le64_to_cpu(quad->logEnd)  &&
572 					mega_mod64((row - le64_to_cpu(quad->logStart)),
573 					le32_to_cpu(quad->diff)) == 0) {
574 					strip = mega_div64_32
575 						(((row - span_set->data_row_start)
576 							- le64_to_cpu(quad->logStart)),
577 							le32_to_cpu(quad->diff));
578 					strip *= span_set->span_row_data_width;
579 					strip += span_set->data_strip_start;
580 					strip += span_set->strip_offset[span];
581 					return strip;
582 				}
583 			}
584 	}
585 	dev_err(&instance->pdev->dev, "get_strip_from_row"
586 		"returns invalid strip for ld=%x, row=%lx\n",
587 		ld, (long unsigned int)row);
588 	return -1;
589 }
590 
591 /*
592 ******************************************************************************
593 *
594 * This routine calculates the Physical Arm for given strip using spanset.
595 *
596 * Inputs :
597 *    instance - HBA instance
598 *    ld   - Logical drive number
599 *    strip      - Strip
600 *    map    - LD map
601 *
602 * Outputs :
603 *
604 *    Phys Arm         - Phys Arm associated with strip
605 */
606 
607 static u32 get_arm_from_strip(struct megasas_instance *instance,
608 	u32 ld, u64 strip, struct MR_DRV_RAID_MAP_ALL *map)
609 {
610 	struct fusion_context *fusion = instance->ctrl_context;
611 	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
612 	LD_SPAN_SET *span_set;
613 	PLD_SPAN_INFO ldSpanInfo = fusion->log_to_span;
614 	u32    info, strip_offset, span, span_offset, retval;
615 
616 	for (info = 0 ; info < MAX_QUAD_DEPTH; info++) {
617 		span_set = &(ldSpanInfo[ld].span_set[info]);
618 
619 		if (span_set->span_row_data_width == 0)
620 			break;
621 		if (strip > span_set->data_strip_end)
622 			continue;
623 
624 		strip_offset = (uint)mega_mod64
625 				((strip - span_set->data_strip_start),
626 				span_set->span_row_data_width);
627 
628 		for (span = 0, span_offset = 0; span < raid->spanDepth; span++)
629 			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
630 				block_span_info.noElements) >= info+1) {
631 				if (strip_offset >=
632 					span_set->strip_offset[span])
633 					span_offset =
634 						span_set->strip_offset[span];
635 				else
636 					break;
637 			}
638 
639 		retval = (strip_offset - span_offset);
640 		return retval;
641 	}
642 
643 	dev_err(&instance->pdev->dev, "get_arm_from_strip"
644 		"returns invalid arm for ld=%x strip=%lx\n",
645 		ld, (long unsigned int)strip);
646 
647 	return -1;
648 }
649 
650 /* This Function will return Phys arm */
651 u8 get_arm(struct megasas_instance *instance, u32 ld, u8 span, u64 stripe,
652 		struct MR_DRV_RAID_MAP_ALL *map)
653 {
654 	struct MR_LD_RAID  *raid = MR_LdRaidGet(ld, map);
655 	/* Need to check correct default value */
656 	u32    arm = 0;
657 
658 	switch (raid->level) {
659 	case 0:
660 	case 5:
661 	case 6:
662 		arm = mega_mod64(stripe, SPAN_ROW_SIZE(map, ld, span));
663 		break;
664 	case 1:
665 		/* start with logical arm */
666 		arm = get_arm_from_strip(instance, ld, stripe, map);
667 		if (arm != -1U)
668 			arm *= 2;
669 		break;
670 	}
671 
672 	return arm;
673 }
674 
675 
676 /*
677 ******************************************************************************
678 *
679 * This routine calculates the arm, span and block for the specified stripe and
680 * reference in stripe using spanset
681 *
682 * Inputs :
683 *
684 *    ld   - Logical drive number
685 *    stripRow        - Stripe number
686 *    stripRef    - Reference in stripe
687 *
688 * Outputs :
689 *
690 *    span          - Span number
691 *    block         - Absolute Block number in the physical disk
692 */
693 static u8 mr_spanset_get_phy_params(struct megasas_instance *instance, u32 ld,
694 		u64 stripRow, u16 stripRef, struct IO_REQUEST_INFO *io_info,
695 		struct RAID_CONTEXT *pRAID_Context,
696 		struct MR_DRV_RAID_MAP_ALL *map)
697 {
698 	struct MR_LD_RAID  *raid = MR_LdRaidGet(ld, map);
699 	u32     pd, arRef, r1_alt_pd;
700 	u8      physArm, span;
701 	u64     row;
702 	u8	retval = true;
703 	u64	*pdBlock = &io_info->pdBlock;
704 	__le16	*pDevHandle = &io_info->devHandle;
705 	u8	*pPdInterface = &io_info->pd_interface;
706 	u32	logArm, rowMod, armQ, arm;
707 	struct fusion_context *fusion;
708 
709 	fusion = instance->ctrl_context;
710 	*pDevHandle = cpu_to_le16(MR_DEVHANDLE_INVALID);
711 
712 	/*Get row and span from io_info for Uneven Span IO.*/
713 	row	    = io_info->start_row;
714 	span	    = io_info->start_span;
715 
716 
717 	if (raid->level == 6) {
718 		logArm = get_arm_from_strip(instance, ld, stripRow, map);
719 		if (logArm == -1U)
720 			return false;
721 		rowMod = mega_mod64(row, SPAN_ROW_SIZE(map, ld, span));
722 		armQ = SPAN_ROW_SIZE(map, ld, span) - 1 - rowMod;
723 		arm = armQ + 1 + logArm;
724 		if (arm >= SPAN_ROW_SIZE(map, ld, span))
725 			arm -= SPAN_ROW_SIZE(map, ld, span);
726 		physArm = (u8)arm;
727 	} else
728 		/* Calculate the arm */
729 		physArm = get_arm(instance, ld, span, stripRow, map);
730 	if (physArm == 0xFF)
731 		return false;
732 
733 	arRef       = MR_LdSpanArrayGet(ld, span, map);
734 	pd          = MR_ArPdGet(arRef, physArm, map);
735 
736 	if (pd != MR_PD_INVALID) {
737 		*pDevHandle = MR_PdDevHandleGet(pd, map);
738 		*pPdInterface = MR_PdInterfaceTypeGet(pd, map);
739 		/* get second pd also for raid 1/10 fast path writes*/
740 		if (instance->is_ventura &&
741 		    (raid->level == 1) &&
742 		    !io_info->isRead) {
743 			r1_alt_pd = MR_ArPdGet(arRef, physArm + 1, map);
744 			if (r1_alt_pd != MR_PD_INVALID)
745 				io_info->r1_alt_dev_handle =
746 				MR_PdDevHandleGet(r1_alt_pd, map);
747 		}
748 	} else {
749 		if ((raid->level >= 5) &&
750 			((fusion->adapter_type == THUNDERBOLT_SERIES)  ||
751 			((fusion->adapter_type == INVADER_SERIES) &&
752 			(raid->regTypeReqOnRead != REGION_TYPE_UNUSED))))
753 			pRAID_Context->reg_lock_flags = REGION_TYPE_EXCLUSIVE;
754 		else if (raid->level == 1) {
755 			physArm = physArm + 1;
756 			pd = MR_ArPdGet(arRef, physArm, map);
757 			if (pd != MR_PD_INVALID) {
758 				*pDevHandle = MR_PdDevHandleGet(pd, map);
759 				*pPdInterface = MR_PdInterfaceTypeGet(pd, map);
760 			}
761 		}
762 	}
763 
764 	*pdBlock += stripRef + le64_to_cpu(MR_LdSpanPtrGet(ld, span, map)->startBlk);
765 	if (instance->is_ventura) {
766 		((struct RAID_CONTEXT_G35 *)pRAID_Context)->span_arm =
767 			(span << RAID_CTX_SPANARM_SPAN_SHIFT) | physArm;
768 		io_info->span_arm =
769 			(span << RAID_CTX_SPANARM_SPAN_SHIFT) | physArm;
770 	} else {
771 		pRAID_Context->span_arm =
772 			(span << RAID_CTX_SPANARM_SPAN_SHIFT) | physArm;
773 		io_info->span_arm = pRAID_Context->span_arm;
774 	}
775 	io_info->pd_after_lb = pd;
776 	return retval;
777 }
778 
779 /*
780 ******************************************************************************
781 *
782 * This routine calculates the arm, span and block for the specified stripe and
783 * reference in stripe.
784 *
785 * Inputs :
786 *
787 *    ld   - Logical drive number
788 *    stripRow        - Stripe number
789 *    stripRef    - Reference in stripe
790 *
791 * Outputs :
792 *
793 *    span          - Span number
794 *    block         - Absolute Block number in the physical disk
795 */
796 u8 MR_GetPhyParams(struct megasas_instance *instance, u32 ld, u64 stripRow,
797 		u16 stripRef, struct IO_REQUEST_INFO *io_info,
798 		struct RAID_CONTEXT *pRAID_Context,
799 		struct MR_DRV_RAID_MAP_ALL *map)
800 {
801 	struct MR_LD_RAID  *raid = MR_LdRaidGet(ld, map);
802 	u32         pd, arRef, r1_alt_pd;
803 	u8          physArm, span;
804 	u64         row;
805 	u8	    retval = true;
806 	u64	    *pdBlock = &io_info->pdBlock;
807 	__le16	    *pDevHandle = &io_info->devHandle;
808 	u8	    *pPdInterface = &io_info->pd_interface;
809 	struct fusion_context *fusion;
810 
811 	fusion = instance->ctrl_context;
812 	*pDevHandle = cpu_to_le16(MR_DEVHANDLE_INVALID);
813 
814 	row =  mega_div64_32(stripRow, raid->rowDataSize);
815 
816 	if (raid->level == 6) {
817 		/* logical arm within row */
818 		u32 logArm =  mega_mod64(stripRow, raid->rowDataSize);
819 		u32 rowMod, armQ, arm;
820 
821 		if (raid->rowSize == 0)
822 			return false;
823 		/* get logical row mod */
824 		rowMod = mega_mod64(row, raid->rowSize);
825 		armQ = raid->rowSize-1-rowMod; /* index of Q drive */
826 		arm = armQ+1+logArm; /* data always logically follows Q */
827 		if (arm >= raid->rowSize) /* handle wrap condition */
828 			arm -= raid->rowSize;
829 		physArm = (u8)arm;
830 	} else  {
831 		if (raid->modFactor == 0)
832 			return false;
833 		physArm = MR_LdDataArmGet(ld,  mega_mod64(stripRow,
834 							  raid->modFactor),
835 					  map);
836 	}
837 
838 	if (raid->spanDepth == 1) {
839 		span = 0;
840 		*pdBlock = row << raid->stripeShift;
841 	} else {
842 		span = (u8)MR_GetSpanBlock(ld, row, pdBlock, map);
843 		if (span == SPAN_INVALID)
844 			return false;
845 	}
846 
847 	/* Get the array on which this span is present */
848 	arRef       = MR_LdSpanArrayGet(ld, span, map);
849 	pd          = MR_ArPdGet(arRef, physArm, map); /* Get the pd */
850 
851 	if (pd != MR_PD_INVALID) {
852 		/* Get dev handle from Pd. */
853 		*pDevHandle = MR_PdDevHandleGet(pd, map);
854 		*pPdInterface = MR_PdInterfaceTypeGet(pd, map);
855 		/* get second pd also for raid 1/10 fast path writes*/
856 		if (instance->is_ventura &&
857 		    (raid->level == 1) &&
858 		    !io_info->isRead) {
859 			r1_alt_pd = MR_ArPdGet(arRef, physArm + 1, map);
860 			if (r1_alt_pd != MR_PD_INVALID)
861 				io_info->r1_alt_dev_handle =
862 					MR_PdDevHandleGet(r1_alt_pd, map);
863 		}
864 	} else {
865 		if ((raid->level >= 5) &&
866 			((fusion->adapter_type == THUNDERBOLT_SERIES)  ||
867 			((fusion->adapter_type == INVADER_SERIES) &&
868 			(raid->regTypeReqOnRead != REGION_TYPE_UNUSED))))
869 			pRAID_Context->reg_lock_flags = REGION_TYPE_EXCLUSIVE;
870 		else if (raid->level == 1) {
871 			/* Get alternate Pd. */
872 			physArm = physArm + 1;
873 			pd = MR_ArPdGet(arRef, physArm, map);
874 			if (pd != MR_PD_INVALID) {
875 				/* Get dev handle from Pd */
876 				*pDevHandle = MR_PdDevHandleGet(pd, map);
877 				*pPdInterface = MR_PdInterfaceTypeGet(pd, map);
878 			}
879 		}
880 	}
881 
882 	*pdBlock += stripRef + le64_to_cpu(MR_LdSpanPtrGet(ld, span, map)->startBlk);
883 	if (instance->is_ventura) {
884 		((struct RAID_CONTEXT_G35 *)pRAID_Context)->span_arm =
885 				(span << RAID_CTX_SPANARM_SPAN_SHIFT) | physArm;
886 		io_info->span_arm =
887 				(span << RAID_CTX_SPANARM_SPAN_SHIFT) | physArm;
888 	} else {
889 		pRAID_Context->span_arm =
890 			(span << RAID_CTX_SPANARM_SPAN_SHIFT) | physArm;
891 		io_info->span_arm = pRAID_Context->span_arm;
892 	}
893 	io_info->pd_after_lb = pd;
894 	return retval;
895 }
896 
897 /*
898 ******************************************************************************
899 *
900 * MR_BuildRaidContext function
901 *
902 * This function will initiate command processing.  The start/end row and strip
903 * information is calculated then the lock is acquired.
904 * This function will return 0 if region lock was acquired OR return num strips
905 */
906 u8
907 MR_BuildRaidContext(struct megasas_instance *instance,
908 		    struct IO_REQUEST_INFO *io_info,
909 		    struct RAID_CONTEXT *pRAID_Context,
910 		    struct MR_DRV_RAID_MAP_ALL *map, u8 **raidLUN)
911 {
912 	struct fusion_context *fusion;
913 	struct MR_LD_RAID  *raid;
914 	u32         stripSize, stripe_mask;
915 	u64         endLba, endStrip, endRow, start_row, start_strip;
916 	u64         regStart;
917 	u32         regSize;
918 	u8          num_strips, numRows;
919 	u16         ref_in_start_stripe, ref_in_end_stripe;
920 	u64         ldStartBlock;
921 	u32         numBlocks, ldTgtId;
922 	u8          isRead;
923 	u8	    retval = 0;
924 	u8	    startlba_span = SPAN_INVALID;
925 	u64 *pdBlock = &io_info->pdBlock;
926 	u16	    ld;
927 
928 	ldStartBlock = io_info->ldStartBlock;
929 	numBlocks = io_info->numBlocks;
930 	ldTgtId = io_info->ldTgtId;
931 	isRead = io_info->isRead;
932 	io_info->IoforUnevenSpan = 0;
933 	io_info->start_span	= SPAN_INVALID;
934 	fusion = instance->ctrl_context;
935 
936 	ld = MR_TargetIdToLdGet(ldTgtId, map);
937 	raid = MR_LdRaidGet(ld, map);
938 	/*check read ahead bit*/
939 	io_info->ra_capable = raid->capability.ra_capable;
940 
941 	/*
942 	 * if rowDataSize @RAID map and spanRowDataSize @SPAN INFO are zero
943 	 * return FALSE
944 	 */
945 	if (raid->rowDataSize == 0) {
946 		if (MR_LdSpanPtrGet(ld, 0, map)->spanRowDataSize == 0)
947 			return false;
948 		else if (instance->UnevenSpanSupport) {
949 			io_info->IoforUnevenSpan = 1;
950 		} else {
951 			dev_info(&instance->pdev->dev,
952 				"raid->rowDataSize is 0, but has SPAN[0]"
953 				"rowDataSize = 0x%0x,"
954 				"but there is _NO_ UnevenSpanSupport\n",
955 				MR_LdSpanPtrGet(ld, 0, map)->spanRowDataSize);
956 			return false;
957 		}
958 	}
959 
960 	stripSize = 1 << raid->stripeShift;
961 	stripe_mask = stripSize-1;
962 
963 
964 	/*
965 	 * calculate starting row and stripe, and number of strips and rows
966 	 */
967 	start_strip         = ldStartBlock >> raid->stripeShift;
968 	ref_in_start_stripe = (u16)(ldStartBlock & stripe_mask);
969 	endLba              = ldStartBlock + numBlocks - 1;
970 	ref_in_end_stripe   = (u16)(endLba & stripe_mask);
971 	endStrip            = endLba >> raid->stripeShift;
972 	num_strips          = (u8)(endStrip - start_strip + 1); /* End strip */
973 
974 	if (io_info->IoforUnevenSpan) {
975 		start_row = get_row_from_strip(instance, ld, start_strip, map);
976 		endRow	  = get_row_from_strip(instance, ld, endStrip, map);
977 		if (start_row == -1ULL || endRow == -1ULL) {
978 			dev_info(&instance->pdev->dev, "return from %s %d."
979 				"Send IO w/o region lock.\n",
980 				__func__, __LINE__);
981 			return false;
982 		}
983 
984 		if (raid->spanDepth == 1) {
985 			startlba_span = 0;
986 			*pdBlock = start_row << raid->stripeShift;
987 		} else
988 			startlba_span = (u8)mr_spanset_get_span_block(instance,
989 						ld, start_row, pdBlock, map);
990 		if (startlba_span == SPAN_INVALID) {
991 			dev_info(&instance->pdev->dev, "return from %s %d"
992 				"for row 0x%llx,start strip %llx"
993 				"endSrip %llx\n", __func__, __LINE__,
994 				(unsigned long long)start_row,
995 				(unsigned long long)start_strip,
996 				(unsigned long long)endStrip);
997 			return false;
998 		}
999 		io_info->start_span	= startlba_span;
1000 		io_info->start_row	= start_row;
1001 	} else {
1002 		start_row = mega_div64_32(start_strip, raid->rowDataSize);
1003 		endRow    = mega_div64_32(endStrip, raid->rowDataSize);
1004 	}
1005 	numRows = (u8)(endRow - start_row + 1);
1006 
1007 	/*
1008 	 * calculate region info.
1009 	 */
1010 
1011 	/* assume region is at the start of the first row */
1012 	regStart            = start_row << raid->stripeShift;
1013 	/* assume this IO needs the full row - we'll adjust if not true */
1014 	regSize             = stripSize;
1015 
1016 	io_info->do_fp_rlbypass = raid->capability.fpBypassRegionLock;
1017 
1018 	/* Check if we can send this I/O via FastPath */
1019 	if (raid->capability.fpCapable) {
1020 		if (isRead)
1021 			io_info->fpOkForIo = (raid->capability.fpReadCapable &&
1022 					      ((num_strips == 1) ||
1023 					       raid->capability.
1024 					       fpReadAcrossStripe));
1025 		else
1026 			io_info->fpOkForIo = (raid->capability.fpWriteCapable &&
1027 					      ((num_strips == 1) ||
1028 					       raid->capability.
1029 					       fpWriteAcrossStripe));
1030 	} else
1031 		io_info->fpOkForIo = false;
1032 
1033 	if (numRows == 1) {
1034 		/* single-strip IOs can always lock only the data needed */
1035 		if (num_strips == 1) {
1036 			regStart += ref_in_start_stripe;
1037 			regSize = numBlocks;
1038 		}
1039 		/* multi-strip IOs always need to full stripe locked */
1040 	} else if (io_info->IoforUnevenSpan == 0) {
1041 		/*
1042 		 * For Even span region lock optimization.
1043 		 * If the start strip is the last in the start row
1044 		 */
1045 		if (start_strip == (start_row + 1) * raid->rowDataSize - 1) {
1046 			regStart += ref_in_start_stripe;
1047 			/* initialize count to sectors from startref to end
1048 			   of strip */
1049 			regSize = stripSize - ref_in_start_stripe;
1050 		}
1051 
1052 		/* add complete rows in the middle of the transfer */
1053 		if (numRows > 2)
1054 			regSize += (numRows-2) << raid->stripeShift;
1055 
1056 		/* if IO ends within first strip of last row*/
1057 		if (endStrip == endRow*raid->rowDataSize)
1058 			regSize += ref_in_end_stripe+1;
1059 		else
1060 			regSize += stripSize;
1061 	} else {
1062 		/*
1063 		 * For Uneven span region lock optimization.
1064 		 * If the start strip is the last in the start row
1065 		 */
1066 		if (start_strip == (get_strip_from_row(instance, ld, start_row, map) +
1067 				SPAN_ROW_DATA_SIZE(map, ld, startlba_span) - 1)) {
1068 			regStart += ref_in_start_stripe;
1069 			/* initialize count to sectors from
1070 			 * startRef to end of strip
1071 			 */
1072 			regSize = stripSize - ref_in_start_stripe;
1073 		}
1074 		/* Add complete rows in the middle of the transfer*/
1075 
1076 		if (numRows > 2)
1077 			/* Add complete rows in the middle of the transfer*/
1078 			regSize += (numRows-2) << raid->stripeShift;
1079 
1080 		/* if IO ends within first strip of last row */
1081 		if (endStrip == get_strip_from_row(instance, ld, endRow, map))
1082 			regSize += ref_in_end_stripe + 1;
1083 		else
1084 			regSize += stripSize;
1085 	}
1086 
1087 	pRAID_Context->timeout_value =
1088 		cpu_to_le16(raid->fpIoTimeoutForLd ?
1089 			    raid->fpIoTimeoutForLd :
1090 			    map->raidMap.fpPdIoTimeoutSec);
1091 	if (fusion->adapter_type == INVADER_SERIES)
1092 		pRAID_Context->reg_lock_flags = (isRead) ?
1093 			raid->regTypeReqOnRead : raid->regTypeReqOnWrite;
1094 	else if (!instance->is_ventura)
1095 		pRAID_Context->reg_lock_flags = (isRead) ?
1096 			REGION_TYPE_SHARED_READ : raid->regTypeReqOnWrite;
1097 	pRAID_Context->virtual_disk_tgt_id = raid->targetId;
1098 	pRAID_Context->reg_lock_row_lba    = cpu_to_le64(regStart);
1099 	pRAID_Context->reg_lock_length    = cpu_to_le32(regSize);
1100 	pRAID_Context->config_seq_num	= raid->seqNum;
1101 	/* save pointer to raid->LUN array */
1102 	*raidLUN = raid->LUN;
1103 
1104 
1105 	/*Get Phy Params only if FP capable, or else leave it to MR firmware
1106 	  to do the calculation.*/
1107 	if (io_info->fpOkForIo) {
1108 		retval = io_info->IoforUnevenSpan ?
1109 				mr_spanset_get_phy_params(instance, ld,
1110 					start_strip, ref_in_start_stripe,
1111 					io_info, pRAID_Context, map) :
1112 				MR_GetPhyParams(instance, ld, start_strip,
1113 					ref_in_start_stripe, io_info,
1114 					pRAID_Context, map);
1115 		/* If IO on an invalid Pd, then FP is not possible.*/
1116 		if (io_info->devHandle == MR_DEVHANDLE_INVALID)
1117 			io_info->fpOkForIo = false;
1118 		return retval;
1119 	} else if (isRead) {
1120 		uint stripIdx;
1121 		for (stripIdx = 0; stripIdx < num_strips; stripIdx++) {
1122 			retval = io_info->IoforUnevenSpan ?
1123 				mr_spanset_get_phy_params(instance, ld,
1124 				    start_strip + stripIdx,
1125 				    ref_in_start_stripe, io_info,
1126 				    pRAID_Context, map) :
1127 				MR_GetPhyParams(instance, ld,
1128 				    start_strip + stripIdx, ref_in_start_stripe,
1129 				    io_info, pRAID_Context, map);
1130 			if (!retval)
1131 				return true;
1132 		}
1133 	}
1134 	return true;
1135 }
1136 
1137 /*
1138 ******************************************************************************
1139 *
1140 * This routine pepare spanset info from Valid Raid map and store it into
1141 * local copy of ldSpanInfo per instance data structure.
1142 *
1143 * Inputs :
1144 * map    - LD map
1145 * ldSpanInfo - ldSpanInfo per HBA instance
1146 *
1147 */
1148 void mr_update_span_set(struct MR_DRV_RAID_MAP_ALL *map,
1149 	PLD_SPAN_INFO ldSpanInfo)
1150 {
1151 	u8   span, count;
1152 	u32  element, span_row_width;
1153 	u64  span_row;
1154 	struct MR_LD_RAID *raid;
1155 	LD_SPAN_SET *span_set, *span_set_prev;
1156 	struct MR_QUAD_ELEMENT    *quad;
1157 	int ldCount;
1158 	u16 ld;
1159 
1160 
1161 	for (ldCount = 0; ldCount < MAX_LOGICAL_DRIVES_EXT; ldCount++) {
1162 		ld = MR_TargetIdToLdGet(ldCount, map);
1163 		if (ld >= (MAX_LOGICAL_DRIVES_EXT - 1))
1164 			continue;
1165 		raid = MR_LdRaidGet(ld, map);
1166 		for (element = 0; element < MAX_QUAD_DEPTH; element++) {
1167 			for (span = 0; span < raid->spanDepth; span++) {
1168 				if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
1169 					block_span_info.noElements) <
1170 					element + 1)
1171 					continue;
1172 				span_set = &(ldSpanInfo[ld].span_set[element]);
1173 				quad = &map->raidMap.ldSpanMap[ld].
1174 					spanBlock[span].block_span_info.
1175 					quad[element];
1176 
1177 				span_set->diff = le32_to_cpu(quad->diff);
1178 
1179 				for (count = 0, span_row_width = 0;
1180 					count < raid->spanDepth; count++) {
1181 					if (le32_to_cpu(map->raidMap.ldSpanMap[ld].
1182 						spanBlock[count].
1183 						block_span_info.
1184 						noElements) >= element + 1) {
1185 						span_set->strip_offset[count] =
1186 							span_row_width;
1187 						span_row_width +=
1188 							MR_LdSpanPtrGet
1189 							(ld, count, map)->spanRowDataSize;
1190 					}
1191 				}
1192 
1193 				span_set->span_row_data_width = span_row_width;
1194 				span_row = mega_div64_32(((le64_to_cpu(quad->logEnd) -
1195 					le64_to_cpu(quad->logStart)) + le32_to_cpu(quad->diff)),
1196 					le32_to_cpu(quad->diff));
1197 
1198 				if (element == 0) {
1199 					span_set->log_start_lba = 0;
1200 					span_set->log_end_lba =
1201 						((span_row << raid->stripeShift)
1202 						* span_row_width) - 1;
1203 
1204 					span_set->span_row_start = 0;
1205 					span_set->span_row_end = span_row - 1;
1206 
1207 					span_set->data_strip_start = 0;
1208 					span_set->data_strip_end =
1209 						(span_row * span_row_width) - 1;
1210 
1211 					span_set->data_row_start = 0;
1212 					span_set->data_row_end =
1213 						(span_row * le32_to_cpu(quad->diff)) - 1;
1214 				} else {
1215 					span_set_prev = &(ldSpanInfo[ld].
1216 							span_set[element - 1]);
1217 					span_set->log_start_lba =
1218 						span_set_prev->log_end_lba + 1;
1219 					span_set->log_end_lba =
1220 						span_set->log_start_lba +
1221 						((span_row << raid->stripeShift)
1222 						* span_row_width) - 1;
1223 
1224 					span_set->span_row_start =
1225 						span_set_prev->span_row_end + 1;
1226 					span_set->span_row_end =
1227 					span_set->span_row_start + span_row - 1;
1228 
1229 					span_set->data_strip_start =
1230 					span_set_prev->data_strip_end + 1;
1231 					span_set->data_strip_end =
1232 						span_set->data_strip_start +
1233 						(span_row * span_row_width) - 1;
1234 
1235 					span_set->data_row_start =
1236 						span_set_prev->data_row_end + 1;
1237 					span_set->data_row_end =
1238 						span_set->data_row_start +
1239 						(span_row * le32_to_cpu(quad->diff)) - 1;
1240 				}
1241 				break;
1242 		}
1243 		if (span == raid->spanDepth)
1244 			break;
1245 	    }
1246 	}
1247 }
1248 
1249 void mr_update_load_balance_params(struct MR_DRV_RAID_MAP_ALL *drv_map,
1250 	struct LD_LOAD_BALANCE_INFO *lbInfo)
1251 {
1252 	int ldCount;
1253 	u16 ld;
1254 	struct MR_LD_RAID *raid;
1255 
1256 	if (lb_pending_cmds > 128 || lb_pending_cmds < 1)
1257 		lb_pending_cmds = LB_PENDING_CMDS_DEFAULT;
1258 
1259 	for (ldCount = 0; ldCount < MAX_LOGICAL_DRIVES_EXT; ldCount++) {
1260 		ld = MR_TargetIdToLdGet(ldCount, drv_map);
1261 		if (ld >= MAX_LOGICAL_DRIVES_EXT) {
1262 			lbInfo[ldCount].loadBalanceFlag = 0;
1263 			continue;
1264 		}
1265 
1266 		raid = MR_LdRaidGet(ld, drv_map);
1267 		if ((raid->level != 1) ||
1268 			(raid->ldState != MR_LD_STATE_OPTIMAL)) {
1269 			lbInfo[ldCount].loadBalanceFlag = 0;
1270 			continue;
1271 		}
1272 		lbInfo[ldCount].loadBalanceFlag = 1;
1273 	}
1274 }
1275 
1276 u8 megasas_get_best_arm_pd(struct megasas_instance *instance,
1277 			   struct LD_LOAD_BALANCE_INFO *lbInfo,
1278 			   struct IO_REQUEST_INFO *io_info,
1279 			   struct MR_DRV_RAID_MAP_ALL *drv_map)
1280 {
1281 	struct MR_LD_RAID  *raid;
1282 	u16	pd1_dev_handle;
1283 	u16     pend0, pend1, ld;
1284 	u64     diff0, diff1;
1285 	u8      bestArm, pd0, pd1, span, arm;
1286 	u32     arRef, span_row_size;
1287 
1288 	u64 block = io_info->ldStartBlock;
1289 	u32 count = io_info->numBlocks;
1290 
1291 	span = ((io_info->span_arm & RAID_CTX_SPANARM_SPAN_MASK)
1292 			>> RAID_CTX_SPANARM_SPAN_SHIFT);
1293 	arm = (io_info->span_arm & RAID_CTX_SPANARM_ARM_MASK);
1294 
1295 	ld = MR_TargetIdToLdGet(io_info->ldTgtId, drv_map);
1296 	raid = MR_LdRaidGet(ld, drv_map);
1297 	span_row_size = instance->UnevenSpanSupport ?
1298 			SPAN_ROW_SIZE(drv_map, ld, span) : raid->rowSize;
1299 
1300 	arRef = MR_LdSpanArrayGet(ld, span, drv_map);
1301 	pd0 = MR_ArPdGet(arRef, arm, drv_map);
1302 	pd1 = MR_ArPdGet(arRef, (arm + 1) >= span_row_size ?
1303 		(arm + 1 - span_row_size) : arm + 1, drv_map);
1304 
1305 	/* Get PD1 Dev Handle */
1306 
1307 	pd1_dev_handle = MR_PdDevHandleGet(pd1, drv_map);
1308 
1309 	if (pd1_dev_handle == MR_DEVHANDLE_INVALID) {
1310 		bestArm = arm;
1311 	} else {
1312 		/* get the pending cmds for the data and mirror arms */
1313 		pend0 = atomic_read(&lbInfo->scsi_pending_cmds[pd0]);
1314 		pend1 = atomic_read(&lbInfo->scsi_pending_cmds[pd1]);
1315 
1316 		/* Determine the disk whose head is nearer to the req. block */
1317 		diff0 = ABS_DIFF(block, lbInfo->last_accessed_block[pd0]);
1318 		diff1 = ABS_DIFF(block, lbInfo->last_accessed_block[pd1]);
1319 		bestArm = (diff0 <= diff1 ? arm : arm ^ 1);
1320 
1321 		/* Make balance count from 16 to 4 to
1322 		 *  keep driver in sync with Firmware
1323 		 */
1324 		if ((bestArm == arm && pend0 > pend1 + lb_pending_cmds)  ||
1325 		    (bestArm != arm && pend1 > pend0 + lb_pending_cmds))
1326 			bestArm ^= 1;
1327 
1328 		/* Update the last accessed block on the correct pd */
1329 		io_info->span_arm =
1330 			(span << RAID_CTX_SPANARM_SPAN_SHIFT) | bestArm;
1331 		io_info->pd_after_lb = (bestArm == arm) ? pd0 : pd1;
1332 	}
1333 
1334 	lbInfo->last_accessed_block[io_info->pd_after_lb] = block + count - 1;
1335 	return io_info->pd_after_lb;
1336 }
1337 
1338 __le16 get_updated_dev_handle(struct megasas_instance *instance,
1339 			      struct LD_LOAD_BALANCE_INFO *lbInfo,
1340 			      struct IO_REQUEST_INFO *io_info,
1341 			      struct MR_DRV_RAID_MAP_ALL *drv_map)
1342 {
1343 	u8 arm_pd;
1344 	__le16 devHandle;
1345 
1346 	/* get best new arm (PD ID) */
1347 	arm_pd  = megasas_get_best_arm_pd(instance, lbInfo, io_info, drv_map);
1348 	devHandle = MR_PdDevHandleGet(arm_pd, drv_map);
1349 	io_info->pd_interface = MR_PdInterfaceTypeGet(arm_pd, drv_map);
1350 	atomic_inc(&lbInfo->scsi_pending_cmds[arm_pd]);
1351 
1352 	return devHandle;
1353 }
1354