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
61static unsigned int lb_pending_cmds = LB_PENDING_CMDS_DEFAULT;
62module_param(lb_pending_cmds, int, S_IRUGO);
63MODULE_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#define FALSE 0
70#define TRUE 1
71
72#define SPAN_DEBUG 0
73#define SPAN_ROW_SIZE(map, ld, index_) (MR_LdSpanPtrGet(ld, index_, map)->spanRowSize)
74#define SPAN_ROW_DATA_SIZE(map_, ld, index_)   (MR_LdSpanPtrGet(ld, index_, map)->spanRowDataSize)
75#define SPAN_INVALID  0xff
76
77/* Prototypes */
78static void mr_update_span_set(struct MR_DRV_RAID_MAP_ALL *map,
79	PLD_SPAN_INFO ldSpanInfo);
80static u8 mr_spanset_get_phy_params(struct megasas_instance *instance, u32 ld,
81	u64 stripRow, u16 stripRef, struct IO_REQUEST_INFO *io_info,
82	struct RAID_CONTEXT *pRAID_Context, struct MR_DRV_RAID_MAP_ALL *map);
83static u64 get_row_from_strip(struct megasas_instance *instance, u32 ld,
84	u64 strip, struct MR_DRV_RAID_MAP_ALL *map);
85
86u32 mega_mod64(u64 dividend, u32 divisor)
87{
88	u64 d;
89	u32 remainder;
90
91	if (!divisor)
92		printk(KERN_ERR "megasas : DIVISOR is zero, in div fn\n");
93	d = dividend;
94	remainder = do_div(d, divisor);
95	return remainder;
96}
97
98/**
99 * @param dividend    : Dividend
100 * @param divisor    : Divisor
101 *
102 * @return quotient
103 **/
104u64 mega_div64_32(uint64_t dividend, uint32_t divisor)
105{
106	u32 remainder;
107	u64 d;
108
109	if (!divisor)
110		printk(KERN_ERR "megasas : DIVISOR is zero in mod fn\n");
111
112	d = dividend;
113	remainder = do_div(d, divisor);
114
115	return d;
116}
117
118struct MR_LD_RAID *MR_LdRaidGet(u32 ld, struct MR_DRV_RAID_MAP_ALL *map)
119{
120	return &map->raidMap.ldSpanMap[ld].ldRaid;
121}
122
123static struct MR_SPAN_BLOCK_INFO *MR_LdSpanInfoGet(u32 ld,
124						   struct MR_DRV_RAID_MAP_ALL
125						   *map)
126{
127	return &map->raidMap.ldSpanMap[ld].spanBlock[0];
128}
129
130static u8 MR_LdDataArmGet(u32 ld, u32 armIdx, struct MR_DRV_RAID_MAP_ALL *map)
131{
132	return map->raidMap.ldSpanMap[ld].dataArmMap[armIdx];
133}
134
135u16 MR_ArPdGet(u32 ar, u32 arm, struct MR_DRV_RAID_MAP_ALL *map)
136{
137	return le16_to_cpu(map->raidMap.arMapInfo[ar].pd[arm]);
138}
139
140u16 MR_LdSpanArrayGet(u32 ld, u32 span, struct MR_DRV_RAID_MAP_ALL *map)
141{
142	return le16_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].span.arrayRef);
143}
144
145u16 MR_PdDevHandleGet(u32 pd, struct MR_DRV_RAID_MAP_ALL *map)
146{
147	return map->raidMap.devHndlInfo[pd].curDevHdl;
148}
149
150u16 MR_GetLDTgtId(u32 ld, struct MR_DRV_RAID_MAP_ALL *map)
151{
152	return le16_to_cpu(map->raidMap.ldSpanMap[ld].ldRaid.targetId);
153}
154
155u8 MR_TargetIdToLdGet(u32 ldTgtId, struct MR_DRV_RAID_MAP_ALL *map)
156{
157	return map->raidMap.ldTgtIdToLd[ldTgtId];
158}
159
160static struct MR_LD_SPAN *MR_LdSpanPtrGet(u32 ld, u32 span,
161					  struct MR_DRV_RAID_MAP_ALL *map)
162{
163	return &map->raidMap.ldSpanMap[ld].spanBlock[span].span;
164}
165
166/*
167 * This function will Populate Driver Map using firmware raid map
168 */
169void MR_PopulateDrvRaidMap(struct megasas_instance *instance)
170{
171	struct fusion_context *fusion = instance->ctrl_context;
172	struct MR_FW_RAID_MAP_ALL     *fw_map_old    = NULL;
173	struct MR_FW_RAID_MAP         *pFwRaidMap    = NULL;
174	int i;
175	u16 ld_count;
176
177
178	struct MR_DRV_RAID_MAP_ALL *drv_map =
179			fusion->ld_drv_map[(instance->map_id & 1)];
180	struct MR_DRV_RAID_MAP *pDrvRaidMap = &drv_map->raidMap;
181
182	if (instance->supportmax256vd) {
183		memcpy(fusion->ld_drv_map[instance->map_id & 1],
184			fusion->ld_map[instance->map_id & 1],
185			fusion->current_map_sz);
186		/* New Raid map will not set totalSize, so keep expected value
187		 * for legacy code in ValidateMapInfo
188		 */
189		pDrvRaidMap->totalSize =
190			cpu_to_le32(sizeof(struct MR_FW_RAID_MAP_EXT));
191	} else {
192		fw_map_old = (struct MR_FW_RAID_MAP_ALL *)
193			fusion->ld_map[(instance->map_id & 1)];
194		pFwRaidMap = &fw_map_old->raidMap;
195		ld_count = (u16)le32_to_cpu(pFwRaidMap->ldCount);
196
197#if VD_EXT_DEBUG
198		for (i = 0; i < ld_count; i++) {
199			dev_dbg(&instance->pdev->dev, "(%d) :Index 0x%x "
200				"Target Id 0x%x Seq Num 0x%x Size 0/%llx\n",
201				instance->unique_id, i,
202				fw_map_old->raidMap.ldSpanMap[i].ldRaid.targetId,
203				fw_map_old->raidMap.ldSpanMap[i].ldRaid.seqNum,
204				fw_map_old->raidMap.ldSpanMap[i].ldRaid.size);
205		}
206#endif
207
208		memset(drv_map, 0, fusion->drv_map_sz);
209		pDrvRaidMap->totalSize = pFwRaidMap->totalSize;
210		pDrvRaidMap->ldCount = (__le16)cpu_to_le16(ld_count);
211		pDrvRaidMap->fpPdIoTimeoutSec = pFwRaidMap->fpPdIoTimeoutSec;
212		for (i = 0; i < MAX_RAIDMAP_LOGICAL_DRIVES + MAX_RAIDMAP_VIEWS; i++)
213			pDrvRaidMap->ldTgtIdToLd[i] =
214				(u8)pFwRaidMap->ldTgtIdToLd[i];
215		for (i = (MAX_RAIDMAP_LOGICAL_DRIVES + MAX_RAIDMAP_VIEWS);
216			i < MAX_LOGICAL_DRIVES_EXT; i++)
217			pDrvRaidMap->ldTgtIdToLd[i] = 0xff;
218		for (i = 0; i < ld_count; i++) {
219			pDrvRaidMap->ldSpanMap[i] = pFwRaidMap->ldSpanMap[i];
220#if VD_EXT_DEBUG
221			dev_dbg(&instance->pdev->dev,
222				"pFwRaidMap->ldSpanMap[%d].ldRaid.targetId 0x%x "
223				"pFwRaidMap->ldSpanMap[%d].ldRaid.seqNum 0x%x "
224				"size 0x%x\n", i, i,
225				pFwRaidMap->ldSpanMap[i].ldRaid.targetId,
226				pFwRaidMap->ldSpanMap[i].ldRaid.seqNum,
227				(u32)pFwRaidMap->ldSpanMap[i].ldRaid.rowSize);
228			dev_dbg(&instance->pdev->dev,
229				"pDrvRaidMap->ldSpanMap[%d].ldRaid.targetId 0x%x "
230				"pDrvRaidMap->ldSpanMap[%d].ldRaid.seqNum 0x%x "
231				"size 0x%x\n", i, i,
232				pDrvRaidMap->ldSpanMap[i].ldRaid.targetId,
233				pDrvRaidMap->ldSpanMap[i].ldRaid.seqNum,
234				(u32)pDrvRaidMap->ldSpanMap[i].ldRaid.rowSize);
235			dev_dbg(&instance->pdev->dev, "Driver raid map all %p "
236				"raid map %p LD RAID MAP %p/%p\n", drv_map,
237				pDrvRaidMap, &pFwRaidMap->ldSpanMap[i].ldRaid,
238				&pDrvRaidMap->ldSpanMap[i].ldRaid);
239#endif
240		}
241		memcpy(pDrvRaidMap->arMapInfo, pFwRaidMap->arMapInfo,
242			sizeof(struct MR_ARRAY_INFO) * MAX_RAIDMAP_ARRAYS);
243		memcpy(pDrvRaidMap->devHndlInfo, pFwRaidMap->devHndlInfo,
244			sizeof(struct MR_DEV_HANDLE_INFO) *
245			MAX_RAIDMAP_PHYSICAL_DEVICES);
246	}
247}
248
249/*
250 * This function will validate Map info data provided by FW
251 */
252u8 MR_ValidateMapInfo(struct megasas_instance *instance)
253{
254	struct fusion_context *fusion;
255	struct MR_DRV_RAID_MAP_ALL *drv_map;
256	struct MR_DRV_RAID_MAP *pDrvRaidMap;
257	struct LD_LOAD_BALANCE_INFO *lbInfo;
258	PLD_SPAN_INFO ldSpanInfo;
259	struct MR_LD_RAID         *raid;
260	u16 ldCount, num_lds;
261	u16 ld;
262	u32 expected_size;
263
264
265	MR_PopulateDrvRaidMap(instance);
266
267	fusion = instance->ctrl_context;
268	drv_map = fusion->ld_drv_map[(instance->map_id & 1)];
269	pDrvRaidMap = &drv_map->raidMap;
270
271	lbInfo = fusion->load_balance_info;
272	ldSpanInfo = fusion->log_to_span;
273
274	if (instance->supportmax256vd)
275		expected_size = sizeof(struct MR_FW_RAID_MAP_EXT);
276	else
277		expected_size =
278			(sizeof(struct MR_FW_RAID_MAP) - sizeof(struct MR_LD_SPAN_MAP) +
279			(sizeof(struct MR_LD_SPAN_MAP) * le16_to_cpu(pDrvRaidMap->ldCount)));
280
281	if (le32_to_cpu(pDrvRaidMap->totalSize) != expected_size) {
282		dev_err(&instance->pdev->dev, "map info structure size 0x%x is not matching with ld count\n",
283		       (unsigned int) expected_size);
284		dev_err(&instance->pdev->dev, "megasas: span map %x, pDrvRaidMap->totalSize : %x\n",
285			(unsigned int)sizeof(struct MR_LD_SPAN_MAP),
286			le32_to_cpu(pDrvRaidMap->totalSize));
287		return 0;
288	}
289
290	if (instance->UnevenSpanSupport)
291		mr_update_span_set(drv_map, ldSpanInfo);
292
293	mr_update_load_balance_params(drv_map, lbInfo);
294
295	num_lds = le16_to_cpu(drv_map->raidMap.ldCount);
296
297	/*Convert Raid capability values to CPU arch */
298	for (ldCount = 0; ldCount < num_lds; ldCount++) {
299		ld = MR_TargetIdToLdGet(ldCount, drv_map);
300		raid = MR_LdRaidGet(ld, drv_map);
301		le32_to_cpus((u32 *)&raid->capability);
302	}
303
304	return 1;
305}
306
307u32 MR_GetSpanBlock(u32 ld, u64 row, u64 *span_blk,
308		    struct MR_DRV_RAID_MAP_ALL *map)
309{
310	struct MR_SPAN_BLOCK_INFO *pSpanBlock = MR_LdSpanInfoGet(ld, map);
311	struct MR_QUAD_ELEMENT    *quad;
312	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
313	u32                span, j;
314
315	for (span = 0; span < raid->spanDepth; span++, pSpanBlock++) {
316
317		for (j = 0; j < le32_to_cpu(pSpanBlock->block_span_info.noElements); j++) {
318			quad = &pSpanBlock->block_span_info.quad[j];
319
320			if (le32_to_cpu(quad->diff) == 0)
321				return SPAN_INVALID;
322			if (le64_to_cpu(quad->logStart) <= row && row <=
323				le64_to_cpu(quad->logEnd) && (mega_mod64(row - le64_to_cpu(quad->logStart),
324				le32_to_cpu(quad->diff))) == 0) {
325				if (span_blk != NULL) {
326					u64  blk, debugBlk;
327					blk =  mega_div64_32((row-le64_to_cpu(quad->logStart)), le32_to_cpu(quad->diff));
328					debugBlk = blk;
329
330					blk = (blk + le64_to_cpu(quad->offsetInSpan)) << raid->stripeShift;
331					*span_blk = blk;
332				}
333				return span;
334			}
335		}
336	}
337	return SPAN_INVALID;
338}
339
340/*
341******************************************************************************
342*
343* Function to print info about span set created in driver from FW raid map
344*
345* Inputs :
346* map    - LD map
347* ldSpanInfo - ldSpanInfo per HBA instance
348*/
349#if SPAN_DEBUG
350static int getSpanInfo(struct MR_DRV_RAID_MAP_ALL *map,
351	PLD_SPAN_INFO ldSpanInfo)
352{
353
354	u8   span;
355	u32    element;
356	struct MR_LD_RAID *raid;
357	LD_SPAN_SET *span_set;
358	struct MR_QUAD_ELEMENT    *quad;
359	int ldCount;
360	u16 ld;
361
362	for (ldCount = 0; ldCount < MAX_LOGICAL_DRIVES_EXT; ldCount++) {
363		ld = MR_TargetIdToLdGet(ldCount, map);
364			if (ld >= (MAX_LOGICAL_DRIVES_EXT - 1))
365				continue;
366		raid = MR_LdRaidGet(ld, map);
367		dev_dbg(&instance->pdev->dev, "LD %x: span_depth=%x\n",
368			ld, raid->spanDepth);
369		for (span = 0; span < raid->spanDepth; span++)
370			dev_dbg(&instance->pdev->dev, "Span=%x,"
371			" number of quads=%x\n", span,
372			le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
373			block_span_info.noElements));
374		for (element = 0; element < MAX_QUAD_DEPTH; element++) {
375			span_set = &(ldSpanInfo[ld].span_set[element]);
376			if (span_set->span_row_data_width == 0)
377				break;
378
379			dev_dbg(&instance->pdev->dev, "Span Set %x:"
380				"width=%x, diff=%x\n", element,
381				(unsigned int)span_set->span_row_data_width,
382				(unsigned int)span_set->diff);
383			dev_dbg(&instance->pdev->dev, "logical LBA"
384				"start=0x%08lx, end=0x%08lx\n",
385				(long unsigned int)span_set->log_start_lba,
386				(long unsigned int)span_set->log_end_lba);
387			dev_dbg(&instance->pdev->dev, "span row start=0x%08lx,"
388				" end=0x%08lx\n",
389				(long unsigned int)span_set->span_row_start,
390				(long unsigned int)span_set->span_row_end);
391			dev_dbg(&instance->pdev->dev, "data row start=0x%08lx,"
392				" end=0x%08lx\n",
393				(long unsigned int)span_set->data_row_start,
394				(long unsigned int)span_set->data_row_end);
395			dev_dbg(&instance->pdev->dev, "data strip start=0x%08lx,"
396				" end=0x%08lx\n",
397				(long unsigned int)span_set->data_strip_start,
398				(long unsigned int)span_set->data_strip_end);
399
400			for (span = 0; span < raid->spanDepth; span++) {
401				if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
402					block_span_info.noElements) >=
403					element + 1) {
404					quad = &map->raidMap.ldSpanMap[ld].
405						spanBlock[span].block_span_info.
406						quad[element];
407				dev_dbg(&instance->pdev->dev, "Span=%x,"
408					"Quad=%x, diff=%x\n", span,
409					element, le32_to_cpu(quad->diff));
410				dev_dbg(&instance->pdev->dev,
411					"offset_in_span=0x%08lx\n",
412					(long unsigned int)le64_to_cpu(quad->offsetInSpan));
413				dev_dbg(&instance->pdev->dev,
414					"logical start=0x%08lx, end=0x%08lx\n",
415					(long unsigned int)le64_to_cpu(quad->logStart),
416					(long unsigned int)le64_to_cpu(quad->logEnd));
417				}
418			}
419		}
420	}
421	return 0;
422}
423#endif
424
425/*
426******************************************************************************
427*
428* This routine calculates the Span block for given row using spanset.
429*
430* Inputs :
431*    instance - HBA instance
432*    ld   - Logical drive number
433*    row        - Row number
434*    map    - LD map
435*
436* Outputs :
437*
438*    span          - Span number
439*    block         - Absolute Block number in the physical disk
440*    div_error	   - Devide error code.
441*/
442
443u32 mr_spanset_get_span_block(struct megasas_instance *instance,
444		u32 ld, u64 row, u64 *span_blk, struct MR_DRV_RAID_MAP_ALL *map)
445{
446	struct fusion_context *fusion = instance->ctrl_context;
447	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
448	LD_SPAN_SET *span_set;
449	struct MR_QUAD_ELEMENT    *quad;
450	u32    span, info;
451	PLD_SPAN_INFO ldSpanInfo = fusion->log_to_span;
452
453	for (info = 0; info < MAX_QUAD_DEPTH; info++) {
454		span_set = &(ldSpanInfo[ld].span_set[info]);
455
456		if (span_set->span_row_data_width == 0)
457			break;
458
459		if (row > span_set->data_row_end)
460			continue;
461
462		for (span = 0; span < raid->spanDepth; span++)
463			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
464				block_span_info.noElements) >= info+1) {
465				quad = &map->raidMap.ldSpanMap[ld].
466					spanBlock[span].
467					block_span_info.quad[info];
468				if (le32_to_cpu(quad->diff) == 0)
469					return SPAN_INVALID;
470				if (le64_to_cpu(quad->logStart) <= row  &&
471					row <= le64_to_cpu(quad->logEnd)  &&
472					(mega_mod64(row - le64_to_cpu(quad->logStart),
473						le32_to_cpu(quad->diff))) == 0) {
474					if (span_blk != NULL) {
475						u64  blk;
476						blk = mega_div64_32
477						    ((row - le64_to_cpu(quad->logStart)),
478						    le32_to_cpu(quad->diff));
479						blk = (blk + le64_to_cpu(quad->offsetInSpan))
480							 << raid->stripeShift;
481						*span_blk = blk;
482					}
483					return span;
484				}
485			}
486	}
487	return SPAN_INVALID;
488}
489
490/*
491******************************************************************************
492*
493* This routine calculates the row for given strip using spanset.
494*
495* Inputs :
496*    instance - HBA instance
497*    ld   - Logical drive number
498*    Strip        - Strip
499*    map    - LD map
500*
501* Outputs :
502*
503*    row         - row associated with strip
504*/
505
506static u64  get_row_from_strip(struct megasas_instance *instance,
507	u32 ld, u64 strip, struct MR_DRV_RAID_MAP_ALL *map)
508{
509	struct fusion_context *fusion = instance->ctrl_context;
510	struct MR_LD_RAID	*raid = MR_LdRaidGet(ld, map);
511	LD_SPAN_SET	*span_set;
512	PLD_SPAN_INFO	ldSpanInfo = fusion->log_to_span;
513	u32		info, strip_offset, span, span_offset;
514	u64		span_set_Strip, span_set_Row, retval;
515
516	for (info = 0; info < MAX_QUAD_DEPTH; info++) {
517		span_set = &(ldSpanInfo[ld].span_set[info]);
518
519		if (span_set->span_row_data_width == 0)
520			break;
521		if (strip > span_set->data_strip_end)
522			continue;
523
524		span_set_Strip = strip - span_set->data_strip_start;
525		strip_offset = mega_mod64(span_set_Strip,
526				span_set->span_row_data_width);
527		span_set_Row = mega_div64_32(span_set_Strip,
528				span_set->span_row_data_width) * span_set->diff;
529		for (span = 0, span_offset = 0; span < raid->spanDepth; span++)
530			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
531				block_span_info.noElements) >= info+1) {
532				if (strip_offset >=
533					span_set->strip_offset[span])
534					span_offset++;
535				else
536					break;
537			}
538#if SPAN_DEBUG
539		dev_info(&instance->pdev->dev, "Strip 0x%llx,"
540			"span_set_Strip 0x%llx, span_set_Row 0x%llx"
541			"data width 0x%llx span offset 0x%x\n", strip,
542			(unsigned long long)span_set_Strip,
543			(unsigned long long)span_set_Row,
544			(unsigned long long)span_set->span_row_data_width,
545			span_offset);
546		dev_info(&instance->pdev->dev, "For strip 0x%llx"
547			"row is 0x%llx\n", strip,
548			(unsigned long long) span_set->data_row_start +
549			(unsigned long long) span_set_Row + (span_offset - 1));
550#endif
551		retval = (span_set->data_row_start + span_set_Row +
552				(span_offset - 1));
553		return retval;
554	}
555	return -1LLU;
556}
557
558
559/*
560******************************************************************************
561*
562* This routine calculates the Start Strip for given row using spanset.
563*
564* Inputs :
565*    instance - HBA instance
566*    ld   - Logical drive number
567*    row        - Row number
568*    map    - LD map
569*
570* Outputs :
571*
572*    Strip         - Start strip associated with row
573*/
574
575static u64 get_strip_from_row(struct megasas_instance *instance,
576		u32 ld, u64 row, struct MR_DRV_RAID_MAP_ALL *map)
577{
578	struct fusion_context *fusion = instance->ctrl_context;
579	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
580	LD_SPAN_SET *span_set;
581	struct MR_QUAD_ELEMENT    *quad;
582	PLD_SPAN_INFO ldSpanInfo = fusion->log_to_span;
583	u32    span, info;
584	u64  strip;
585
586	for (info = 0; info < MAX_QUAD_DEPTH; info++) {
587		span_set = &(ldSpanInfo[ld].span_set[info]);
588
589		if (span_set->span_row_data_width == 0)
590			break;
591		if (row > span_set->data_row_end)
592			continue;
593
594		for (span = 0; span < raid->spanDepth; span++)
595			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
596				block_span_info.noElements) >= info+1) {
597				quad = &map->raidMap.ldSpanMap[ld].
598					spanBlock[span].block_span_info.quad[info];
599				if (le64_to_cpu(quad->logStart) <= row  &&
600					row <= le64_to_cpu(quad->logEnd)  &&
601					mega_mod64((row - le64_to_cpu(quad->logStart)),
602					le32_to_cpu(quad->diff)) == 0) {
603					strip = mega_div64_32
604						(((row - span_set->data_row_start)
605							- le64_to_cpu(quad->logStart)),
606							le32_to_cpu(quad->diff));
607					strip *= span_set->span_row_data_width;
608					strip += span_set->data_strip_start;
609					strip += span_set->strip_offset[span];
610					return strip;
611				}
612			}
613	}
614	dev_err(&instance->pdev->dev, "get_strip_from_row"
615		"returns invalid strip for ld=%x, row=%lx\n",
616		ld, (long unsigned int)row);
617	return -1;
618}
619
620/*
621******************************************************************************
622*
623* This routine calculates the Physical Arm for given strip using spanset.
624*
625* Inputs :
626*    instance - HBA instance
627*    ld   - Logical drive number
628*    strip      - Strip
629*    map    - LD map
630*
631* Outputs :
632*
633*    Phys Arm         - Phys Arm associated with strip
634*/
635
636static u32 get_arm_from_strip(struct megasas_instance *instance,
637	u32 ld, u64 strip, struct MR_DRV_RAID_MAP_ALL *map)
638{
639	struct fusion_context *fusion = instance->ctrl_context;
640	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
641	LD_SPAN_SET *span_set;
642	PLD_SPAN_INFO ldSpanInfo = fusion->log_to_span;
643	u32    info, strip_offset, span, span_offset, retval;
644
645	for (info = 0 ; info < MAX_QUAD_DEPTH; info++) {
646		span_set = &(ldSpanInfo[ld].span_set[info]);
647
648		if (span_set->span_row_data_width == 0)
649			break;
650		if (strip > span_set->data_strip_end)
651			continue;
652
653		strip_offset = (uint)mega_mod64
654				((strip - span_set->data_strip_start),
655				span_set->span_row_data_width);
656
657		for (span = 0, span_offset = 0; span < raid->spanDepth; span++)
658			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
659				block_span_info.noElements) >= info+1) {
660				if (strip_offset >=
661					span_set->strip_offset[span])
662					span_offset =
663						span_set->strip_offset[span];
664				else
665					break;
666			}
667#if SPAN_DEBUG
668		dev_info(&instance->pdev->dev, "get_arm_from_strip:"
669			"for ld=0x%x strip=0x%lx arm is  0x%x\n", ld,
670			(long unsigned int)strip, (strip_offset - span_offset));
671#endif
672		retval = (strip_offset - span_offset);
673		return retval;
674	}
675
676	dev_err(&instance->pdev->dev, "get_arm_from_strip"
677		"returns invalid arm for ld=%x strip=%lx\n",
678		ld, (long unsigned int)strip);
679
680	return -1;
681}
682
683/* This Function will return Phys arm */
684u8 get_arm(struct megasas_instance *instance, u32 ld, u8 span, u64 stripe,
685		struct MR_DRV_RAID_MAP_ALL *map)
686{
687	struct MR_LD_RAID  *raid = MR_LdRaidGet(ld, map);
688	/* Need to check correct default value */
689	u32    arm = 0;
690
691	switch (raid->level) {
692	case 0:
693	case 5:
694	case 6:
695		arm = mega_mod64(stripe, SPAN_ROW_SIZE(map, ld, span));
696		break;
697	case 1:
698		/* start with logical arm */
699		arm = get_arm_from_strip(instance, ld, stripe, map);
700		if (arm != -1U)
701			arm *= 2;
702		break;
703	}
704
705	return arm;
706}
707
708
709/*
710******************************************************************************
711*
712* This routine calculates the arm, span and block for the specified stripe and
713* reference in stripe using spanset
714*
715* Inputs :
716*
717*    ld   - Logical drive number
718*    stripRow        - Stripe number
719*    stripRef    - Reference in stripe
720*
721* Outputs :
722*
723*    span          - Span number
724*    block         - Absolute Block number in the physical disk
725*/
726static u8 mr_spanset_get_phy_params(struct megasas_instance *instance, u32 ld,
727		u64 stripRow, u16 stripRef, struct IO_REQUEST_INFO *io_info,
728		struct RAID_CONTEXT *pRAID_Context,
729		struct MR_DRV_RAID_MAP_ALL *map)
730{
731	struct MR_LD_RAID  *raid = MR_LdRaidGet(ld, map);
732	u32     pd, arRef;
733	u8      physArm, span;
734	u64     row;
735	u8	retval = TRUE;
736	u8	do_invader = 0;
737	u64	*pdBlock = &io_info->pdBlock;
738	u16	*pDevHandle = &io_info->devHandle;
739	u32	logArm, rowMod, armQ, arm;
740
741	if ((instance->pdev->device == PCI_DEVICE_ID_LSI_INVADER ||
742		instance->pdev->device == PCI_DEVICE_ID_LSI_FURY))
743		do_invader = 1;
744
745	/*Get row and span from io_info for Uneven Span IO.*/
746	row	    = io_info->start_row;
747	span	    = io_info->start_span;
748
749
750	if (raid->level == 6) {
751		logArm = get_arm_from_strip(instance, ld, stripRow, map);
752		if (logArm == -1U)
753			return FALSE;
754		rowMod = mega_mod64(row, SPAN_ROW_SIZE(map, ld, span));
755		armQ = SPAN_ROW_SIZE(map, ld, span) - 1 - rowMod;
756		arm = armQ + 1 + logArm;
757		if (arm >= SPAN_ROW_SIZE(map, ld, span))
758			arm -= SPAN_ROW_SIZE(map, ld, span);
759		physArm = (u8)arm;
760	} else
761		/* Calculate the arm */
762		physArm = get_arm(instance, ld, span, stripRow, map);
763	if (physArm == 0xFF)
764		return FALSE;
765
766	arRef       = MR_LdSpanArrayGet(ld, span, map);
767	pd          = MR_ArPdGet(arRef, physArm, map);
768
769	if (pd != MR_PD_INVALID)
770		*pDevHandle = MR_PdDevHandleGet(pd, map);
771	else {
772		*pDevHandle = MR_PD_INVALID;
773		if ((raid->level >= 5) &&
774			(!do_invader  || (do_invader &&
775			(raid->regTypeReqOnRead != REGION_TYPE_UNUSED))))
776			pRAID_Context->regLockFlags = REGION_TYPE_EXCLUSIVE;
777		else if (raid->level == 1) {
778			pd = MR_ArPdGet(arRef, physArm + 1, map);
779			if (pd != MR_PD_INVALID)
780				*pDevHandle = MR_PdDevHandleGet(pd, map);
781		}
782	}
783
784	*pdBlock += stripRef + le64_to_cpu(MR_LdSpanPtrGet(ld, span, map)->startBlk);
785	pRAID_Context->spanArm = (span << RAID_CTX_SPANARM_SPAN_SHIFT) |
786					physArm;
787	io_info->span_arm = pRAID_Context->spanArm;
788	return retval;
789}
790
791/*
792******************************************************************************
793*
794* This routine calculates the arm, span and block for the specified stripe and
795* reference in stripe.
796*
797* Inputs :
798*
799*    ld   - Logical drive number
800*    stripRow        - Stripe number
801*    stripRef    - Reference in stripe
802*
803* Outputs :
804*
805*    span          - Span number
806*    block         - Absolute Block number in the physical disk
807*/
808u8 MR_GetPhyParams(struct megasas_instance *instance, u32 ld, u64 stripRow,
809		u16 stripRef, struct IO_REQUEST_INFO *io_info,
810		struct RAID_CONTEXT *pRAID_Context,
811		struct MR_DRV_RAID_MAP_ALL *map)
812{
813	struct MR_LD_RAID  *raid = MR_LdRaidGet(ld, map);
814	u32         pd, arRef;
815	u8          physArm, span;
816	u64         row;
817	u8	    retval = TRUE;
818	u8          do_invader = 0;
819	u64	    *pdBlock = &io_info->pdBlock;
820	u16	    *pDevHandle = &io_info->devHandle;
821
822	if ((instance->pdev->device == PCI_DEVICE_ID_LSI_INVADER ||
823		instance->pdev->device == PCI_DEVICE_ID_LSI_FURY))
824		do_invader = 1;
825
826	row =  mega_div64_32(stripRow, raid->rowDataSize);
827
828	if (raid->level == 6) {
829		/* logical arm within row */
830		u32 logArm =  mega_mod64(stripRow, raid->rowDataSize);
831		u32 rowMod, armQ, arm;
832
833		if (raid->rowSize == 0)
834			return FALSE;
835		/* get logical row mod */
836		rowMod = mega_mod64(row, raid->rowSize);
837		armQ = raid->rowSize-1-rowMod; /* index of Q drive */
838		arm = armQ+1+logArm; /* data always logically follows Q */
839		if (arm >= raid->rowSize) /* handle wrap condition */
840			arm -= raid->rowSize;
841		physArm = (u8)arm;
842	} else  {
843		if (raid->modFactor == 0)
844			return FALSE;
845		physArm = MR_LdDataArmGet(ld,  mega_mod64(stripRow,
846							  raid->modFactor),
847					  map);
848	}
849
850	if (raid->spanDepth == 1) {
851		span = 0;
852		*pdBlock = row << raid->stripeShift;
853	} else {
854		span = (u8)MR_GetSpanBlock(ld, row, pdBlock, map);
855		if (span == SPAN_INVALID)
856			return FALSE;
857	}
858
859	/* Get the array on which this span is present */
860	arRef       = MR_LdSpanArrayGet(ld, span, map);
861	pd          = MR_ArPdGet(arRef, physArm, map); /* Get the pd */
862
863	if (pd != MR_PD_INVALID)
864		/* Get dev handle from Pd. */
865		*pDevHandle = MR_PdDevHandleGet(pd, map);
866	else {
867		*pDevHandle = MR_PD_INVALID; /* set dev handle as invalid. */
868		if ((raid->level >= 5) &&
869			(!do_invader  || (do_invader &&
870			(raid->regTypeReqOnRead != REGION_TYPE_UNUSED))))
871			pRAID_Context->regLockFlags = REGION_TYPE_EXCLUSIVE;
872		else if (raid->level == 1) {
873			/* Get alternate Pd. */
874			pd = MR_ArPdGet(arRef, physArm + 1, map);
875			if (pd != MR_PD_INVALID)
876				/* Get dev handle from Pd */
877				*pDevHandle = MR_PdDevHandleGet(pd, map);
878		}
879	}
880
881	*pdBlock += stripRef + le64_to_cpu(MR_LdSpanPtrGet(ld, span, map)->startBlk);
882	pRAID_Context->spanArm = (span << RAID_CTX_SPANARM_SPAN_SHIFT) |
883		physArm;
884	io_info->span_arm = pRAID_Context->spanArm;
885	return retval;
886}
887
888/*
889******************************************************************************
890*
891* MR_BuildRaidContext function
892*
893* This function will initiate command processing.  The start/end row and strip
894* information is calculated then the lock is acquired.
895* This function will return 0 if region lock was acquired OR return num strips
896*/
897u8
898MR_BuildRaidContext(struct megasas_instance *instance,
899		    struct IO_REQUEST_INFO *io_info,
900		    struct RAID_CONTEXT *pRAID_Context,
901		    struct MR_DRV_RAID_MAP_ALL *map, u8 **raidLUN)
902{
903	struct MR_LD_RAID  *raid;
904	u32         ld, stripSize, stripe_mask;
905	u64         endLba, endStrip, endRow, start_row, start_strip;
906	u64         regStart;
907	u32         regSize;
908	u8          num_strips, numRows;
909	u16         ref_in_start_stripe, ref_in_end_stripe;
910	u64         ldStartBlock;
911	u32         numBlocks, ldTgtId;
912	u8          isRead;
913	u8	    retval = 0;
914	u8	    startlba_span = SPAN_INVALID;
915	u64 *pdBlock = &io_info->pdBlock;
916
917	ldStartBlock = io_info->ldStartBlock;
918	numBlocks = io_info->numBlocks;
919	ldTgtId = io_info->ldTgtId;
920	isRead = io_info->isRead;
921	io_info->IoforUnevenSpan = 0;
922	io_info->start_span	= SPAN_INVALID;
923
924	ld = MR_TargetIdToLdGet(ldTgtId, map);
925	raid = MR_LdRaidGet(ld, map);
926
927	/*
928	 * if rowDataSize @RAID map and spanRowDataSize @SPAN INFO are zero
929	 * return FALSE
930	 */
931	if (raid->rowDataSize == 0) {
932		if (MR_LdSpanPtrGet(ld, 0, map)->spanRowDataSize == 0)
933			return FALSE;
934		else if (instance->UnevenSpanSupport) {
935			io_info->IoforUnevenSpan = 1;
936		} else {
937			dev_info(&instance->pdev->dev,
938				"raid->rowDataSize is 0, but has SPAN[0]"
939				"rowDataSize = 0x%0x,"
940				"but there is _NO_ UnevenSpanSupport\n",
941				MR_LdSpanPtrGet(ld, 0, map)->spanRowDataSize);
942			return FALSE;
943		}
944	}
945
946	stripSize = 1 << raid->stripeShift;
947	stripe_mask = stripSize-1;
948
949
950	/*
951	 * calculate starting row and stripe, and number of strips and rows
952	 */
953	start_strip         = ldStartBlock >> raid->stripeShift;
954	ref_in_start_stripe = (u16)(ldStartBlock & stripe_mask);
955	endLba              = ldStartBlock + numBlocks - 1;
956	ref_in_end_stripe   = (u16)(endLba & stripe_mask);
957	endStrip            = endLba >> raid->stripeShift;
958	num_strips          = (u8)(endStrip - start_strip + 1); /* End strip */
959
960	if (io_info->IoforUnevenSpan) {
961		start_row = get_row_from_strip(instance, ld, start_strip, map);
962		endRow	  = get_row_from_strip(instance, ld, endStrip, map);
963		if (start_row == -1ULL || endRow == -1ULL) {
964			dev_info(&instance->pdev->dev, "return from %s %d."
965				"Send IO w/o region lock.\n",
966				__func__, __LINE__);
967			return FALSE;
968		}
969
970		if (raid->spanDepth == 1) {
971			startlba_span = 0;
972			*pdBlock = start_row << raid->stripeShift;
973		} else
974			startlba_span = (u8)mr_spanset_get_span_block(instance,
975						ld, start_row, pdBlock, map);
976		if (startlba_span == SPAN_INVALID) {
977			dev_info(&instance->pdev->dev, "return from %s %d"
978				"for row 0x%llx,start strip %llx"
979				"endSrip %llx\n", __func__, __LINE__,
980				(unsigned long long)start_row,
981				(unsigned long long)start_strip,
982				(unsigned long long)endStrip);
983			return FALSE;
984		}
985		io_info->start_span	= startlba_span;
986		io_info->start_row	= start_row;
987#if SPAN_DEBUG
988		dev_dbg(&instance->pdev->dev, "Check Span number from %s %d"
989			"for row 0x%llx, start strip 0x%llx end strip 0x%llx"
990			" span 0x%x\n", __func__, __LINE__,
991			(unsigned long long)start_row,
992			(unsigned long long)start_strip,
993			(unsigned long long)endStrip, startlba_span);
994		dev_dbg(&instance->pdev->dev, "start_row 0x%llx endRow 0x%llx"
995			"Start span 0x%x\n", (unsigned long long)start_row,
996			(unsigned long long)endRow, startlba_span);
997#endif
998	} else {
999		start_row = mega_div64_32(start_strip, raid->rowDataSize);
1000		endRow    = mega_div64_32(endStrip, raid->rowDataSize);
1001	}
1002	numRows = (u8)(endRow - start_row + 1);
1003
1004	/*
1005	 * calculate region info.
1006	 */
1007
1008	/* assume region is at the start of the first row */
1009	regStart            = start_row << raid->stripeShift;
1010	/* assume this IO needs the full row - we'll adjust if not true */
1011	regSize             = stripSize;
1012
1013	/* Check if we can send this I/O via FastPath */
1014	if (raid->capability.fpCapable) {
1015		if (isRead)
1016			io_info->fpOkForIo = (raid->capability.fpReadCapable &&
1017					      ((num_strips == 1) ||
1018					       raid->capability.
1019					       fpReadAcrossStripe));
1020		else
1021			io_info->fpOkForIo = (raid->capability.fpWriteCapable &&
1022					      ((num_strips == 1) ||
1023					       raid->capability.
1024					       fpWriteAcrossStripe));
1025	} else
1026		io_info->fpOkForIo = FALSE;
1027
1028	if (numRows == 1) {
1029		/* single-strip IOs can always lock only the data needed */
1030		if (num_strips == 1) {
1031			regStart += ref_in_start_stripe;
1032			regSize = numBlocks;
1033		}
1034		/* multi-strip IOs always need to full stripe locked */
1035	} else if (io_info->IoforUnevenSpan == 0) {
1036		/*
1037		 * For Even span region lock optimization.
1038		 * If the start strip is the last in the start row
1039		 */
1040		if (start_strip == (start_row + 1) * raid->rowDataSize - 1) {
1041			regStart += ref_in_start_stripe;
1042			/* initialize count to sectors from startref to end
1043			   of strip */
1044			regSize = stripSize - ref_in_start_stripe;
1045		}
1046
1047		/* add complete rows in the middle of the transfer */
1048		if (numRows > 2)
1049			regSize += (numRows-2) << raid->stripeShift;
1050
1051		/* if IO ends within first strip of last row*/
1052		if (endStrip == endRow*raid->rowDataSize)
1053			regSize += ref_in_end_stripe+1;
1054		else
1055			regSize += stripSize;
1056	} else {
1057		/*
1058		 * For Uneven span region lock optimization.
1059		 * If the start strip is the last in the start row
1060		 */
1061		if (start_strip == (get_strip_from_row(instance, ld, start_row, map) +
1062				SPAN_ROW_DATA_SIZE(map, ld, startlba_span) - 1)) {
1063			regStart += ref_in_start_stripe;
1064			/* initialize count to sectors from
1065			 * startRef to end of strip
1066			 */
1067			regSize = stripSize - ref_in_start_stripe;
1068		}
1069		/* Add complete rows in the middle of the transfer*/
1070
1071		if (numRows > 2)
1072			/* Add complete rows in the middle of the transfer*/
1073			regSize += (numRows-2) << raid->stripeShift;
1074
1075		/* if IO ends within first strip of last row */
1076		if (endStrip == get_strip_from_row(instance, ld, endRow, map))
1077			regSize += ref_in_end_stripe + 1;
1078		else
1079			regSize += stripSize;
1080	}
1081
1082	pRAID_Context->timeoutValue =
1083		cpu_to_le16(raid->fpIoTimeoutForLd ?
1084			    raid->fpIoTimeoutForLd :
1085			    map->raidMap.fpPdIoTimeoutSec);
1086	if ((instance->pdev->device == PCI_DEVICE_ID_LSI_INVADER) ||
1087		(instance->pdev->device == PCI_DEVICE_ID_LSI_FURY))
1088		pRAID_Context->regLockFlags = (isRead) ?
1089			raid->regTypeReqOnRead : raid->regTypeReqOnWrite;
1090	else
1091		pRAID_Context->regLockFlags = (isRead) ?
1092			REGION_TYPE_SHARED_READ : raid->regTypeReqOnWrite;
1093	pRAID_Context->VirtualDiskTgtId = raid->targetId;
1094	pRAID_Context->regLockRowLBA    = cpu_to_le64(regStart);
1095	pRAID_Context->regLockLength    = cpu_to_le32(regSize);
1096	pRAID_Context->configSeqNum	= raid->seqNum;
1097	/* save pointer to raid->LUN array */
1098	*raidLUN = raid->LUN;
1099
1100
1101	/*Get Phy Params only if FP capable, or else leave it to MR firmware
1102	  to do the calculation.*/
1103	if (io_info->fpOkForIo) {
1104		retval = io_info->IoforUnevenSpan ?
1105				mr_spanset_get_phy_params(instance, ld,
1106					start_strip, ref_in_start_stripe,
1107					io_info, pRAID_Context, map) :
1108				MR_GetPhyParams(instance, ld, start_strip,
1109					ref_in_start_stripe, io_info,
1110					pRAID_Context, map);
1111		/* If IO on an invalid Pd, then FP is not possible.*/
1112		if (io_info->devHandle == MR_PD_INVALID)
1113			io_info->fpOkForIo = FALSE;
1114		return retval;
1115	} else if (isRead) {
1116		uint stripIdx;
1117		for (stripIdx = 0; stripIdx < num_strips; stripIdx++) {
1118			retval = io_info->IoforUnevenSpan ?
1119				mr_spanset_get_phy_params(instance, ld,
1120				    start_strip + stripIdx,
1121				    ref_in_start_stripe, io_info,
1122				    pRAID_Context, map) :
1123				MR_GetPhyParams(instance, ld,
1124				    start_strip + stripIdx, ref_in_start_stripe,
1125				    io_info, pRAID_Context, map);
1126			if (!retval)
1127				return TRUE;
1128		}
1129	}
1130
1131#if SPAN_DEBUG
1132	/* Just for testing what arm we get for strip.*/
1133	if (io_info->IoforUnevenSpan)
1134		get_arm_from_strip(instance, ld, start_strip, map);
1135#endif
1136	return TRUE;
1137}
1138
1139/*
1140******************************************************************************
1141*
1142* This routine pepare spanset info from Valid Raid map and store it into
1143* local copy of ldSpanInfo per instance data structure.
1144*
1145* Inputs :
1146* map    - LD map
1147* ldSpanInfo - ldSpanInfo per HBA instance
1148*
1149*/
1150void mr_update_span_set(struct MR_DRV_RAID_MAP_ALL *map,
1151	PLD_SPAN_INFO ldSpanInfo)
1152{
1153	u8   span, count;
1154	u32  element, span_row_width;
1155	u64  span_row;
1156	struct MR_LD_RAID *raid;
1157	LD_SPAN_SET *span_set, *span_set_prev;
1158	struct MR_QUAD_ELEMENT    *quad;
1159	int ldCount;
1160	u16 ld;
1161
1162
1163	for (ldCount = 0; ldCount < MAX_LOGICAL_DRIVES_EXT; ldCount++) {
1164		ld = MR_TargetIdToLdGet(ldCount, map);
1165		if (ld >= (MAX_LOGICAL_DRIVES_EXT - 1))
1166			continue;
1167		raid = MR_LdRaidGet(ld, map);
1168		for (element = 0; element < MAX_QUAD_DEPTH; element++) {
1169			for (span = 0; span < raid->spanDepth; span++) {
1170				if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
1171					block_span_info.noElements) <
1172					element + 1)
1173					continue;
1174				span_set = &(ldSpanInfo[ld].span_set[element]);
1175				quad = &map->raidMap.ldSpanMap[ld].
1176					spanBlock[span].block_span_info.
1177					quad[element];
1178
1179				span_set->diff = le32_to_cpu(quad->diff);
1180
1181				for (count = 0, span_row_width = 0;
1182					count < raid->spanDepth; count++) {
1183					if (le32_to_cpu(map->raidMap.ldSpanMap[ld].
1184						spanBlock[count].
1185						block_span_info.
1186						noElements) >= element + 1) {
1187						span_set->strip_offset[count] =
1188							span_row_width;
1189						span_row_width +=
1190							MR_LdSpanPtrGet
1191							(ld, count, map)->spanRowDataSize;
1192						printk(KERN_INFO "megasas:"
1193							"span %x rowDataSize %x\n",
1194							count, MR_LdSpanPtrGet
1195							(ld, count, map)->spanRowDataSize);
1196					}
1197				}
1198
1199				span_set->span_row_data_width = span_row_width;
1200				span_row = mega_div64_32(((le64_to_cpu(quad->logEnd) -
1201					le64_to_cpu(quad->logStart)) + le32_to_cpu(quad->diff)),
1202					le32_to_cpu(quad->diff));
1203
1204				if (element == 0) {
1205					span_set->log_start_lba = 0;
1206					span_set->log_end_lba =
1207						((span_row << raid->stripeShift)
1208						* span_row_width) - 1;
1209
1210					span_set->span_row_start = 0;
1211					span_set->span_row_end = span_row - 1;
1212
1213					span_set->data_strip_start = 0;
1214					span_set->data_strip_end =
1215						(span_row * span_row_width) - 1;
1216
1217					span_set->data_row_start = 0;
1218					span_set->data_row_end =
1219						(span_row * le32_to_cpu(quad->diff)) - 1;
1220				} else {
1221					span_set_prev = &(ldSpanInfo[ld].
1222							span_set[element - 1]);
1223					span_set->log_start_lba =
1224						span_set_prev->log_end_lba + 1;
1225					span_set->log_end_lba =
1226						span_set->log_start_lba +
1227						((span_row << raid->stripeShift)
1228						* span_row_width) - 1;
1229
1230					span_set->span_row_start =
1231						span_set_prev->span_row_end + 1;
1232					span_set->span_row_end =
1233					span_set->span_row_start + span_row - 1;
1234
1235					span_set->data_strip_start =
1236					span_set_prev->data_strip_end + 1;
1237					span_set->data_strip_end =
1238						span_set->data_strip_start +
1239						(span_row * span_row_width) - 1;
1240
1241					span_set->data_row_start =
1242						span_set_prev->data_row_end + 1;
1243					span_set->data_row_end =
1244						span_set->data_row_start +
1245						(span_row * le32_to_cpu(quad->diff)) - 1;
1246				}
1247				break;
1248		}
1249		if (span == raid->spanDepth)
1250			break;
1251	    }
1252	}
1253#if SPAN_DEBUG
1254	getSpanInfo(map, ldSpanInfo);
1255#endif
1256
1257}
1258
1259void mr_update_load_balance_params(struct MR_DRV_RAID_MAP_ALL *drv_map,
1260	struct LD_LOAD_BALANCE_INFO *lbInfo)
1261{
1262	int ldCount;
1263	u16 ld;
1264	struct MR_LD_RAID *raid;
1265
1266	if (lb_pending_cmds > 128 || lb_pending_cmds < 1)
1267		lb_pending_cmds = LB_PENDING_CMDS_DEFAULT;
1268
1269	for (ldCount = 0; ldCount < MAX_LOGICAL_DRIVES_EXT; ldCount++) {
1270		ld = MR_TargetIdToLdGet(ldCount, drv_map);
1271		if (ld >= MAX_LOGICAL_DRIVES_EXT) {
1272			lbInfo[ldCount].loadBalanceFlag = 0;
1273			continue;
1274		}
1275
1276		raid = MR_LdRaidGet(ld, drv_map);
1277		if ((raid->level != 1) ||
1278			(raid->ldState != MR_LD_STATE_OPTIMAL)) {
1279			lbInfo[ldCount].loadBalanceFlag = 0;
1280			continue;
1281		}
1282		lbInfo[ldCount].loadBalanceFlag = 1;
1283	}
1284}
1285
1286u8 megasas_get_best_arm_pd(struct megasas_instance *instance,
1287	struct LD_LOAD_BALANCE_INFO *lbInfo, struct IO_REQUEST_INFO *io_info)
1288{
1289	struct fusion_context *fusion;
1290	struct MR_LD_RAID  *raid;
1291	struct MR_DRV_RAID_MAP_ALL *drv_map;
1292	u16     pend0, pend1, ld;
1293	u64     diff0, diff1;
1294	u8      bestArm, pd0, pd1, span, arm;
1295	u32     arRef, span_row_size;
1296
1297	u64 block = io_info->ldStartBlock;
1298	u32 count = io_info->numBlocks;
1299
1300	span = ((io_info->span_arm & RAID_CTX_SPANARM_SPAN_MASK)
1301			>> RAID_CTX_SPANARM_SPAN_SHIFT);
1302	arm = (io_info->span_arm & RAID_CTX_SPANARM_ARM_MASK);
1303
1304
1305	fusion = instance->ctrl_context;
1306	drv_map = fusion->ld_drv_map[(instance->map_id & 1)];
1307	ld = MR_TargetIdToLdGet(io_info->ldTgtId, drv_map);
1308	raid = MR_LdRaidGet(ld, drv_map);
1309	span_row_size = instance->UnevenSpanSupport ?
1310			SPAN_ROW_SIZE(drv_map, ld, span) : raid->rowSize;
1311
1312	arRef = MR_LdSpanArrayGet(ld, span, drv_map);
1313	pd0 = MR_ArPdGet(arRef, arm, drv_map);
1314	pd1 = MR_ArPdGet(arRef, (arm + 1) >= span_row_size ?
1315		(arm + 1 - span_row_size) : arm + 1, drv_map);
1316
1317	/* get the pending cmds for the data and mirror arms */
1318	pend0 = atomic_read(&lbInfo->scsi_pending_cmds[pd0]);
1319	pend1 = atomic_read(&lbInfo->scsi_pending_cmds[pd1]);
1320
1321	/* Determine the disk whose head is nearer to the req. block */
1322	diff0 = ABS_DIFF(block, lbInfo->last_accessed_block[pd0]);
1323	diff1 = ABS_DIFF(block, lbInfo->last_accessed_block[pd1]);
1324	bestArm = (diff0 <= diff1 ? arm : arm ^ 1);
1325
1326	if ((bestArm == arm && pend0 > pend1 + lb_pending_cmds)  ||
1327			(bestArm != arm && pend1 > pend0 + lb_pending_cmds))
1328		bestArm ^= 1;
1329
1330	/* Update the last accessed block on the correct pd */
1331	io_info->pd_after_lb = (bestArm == arm) ? pd0 : pd1;
1332	lbInfo->last_accessed_block[io_info->pd_after_lb] = block + count - 1;
1333	io_info->span_arm = (span << RAID_CTX_SPANARM_SPAN_SHIFT) | bestArm;
1334#if SPAN_DEBUG
1335	if (arm != bestArm)
1336		dev_dbg(&instance->pdev->dev, "LSI Debug R1 Load balance "
1337			"occur - span 0x%x arm 0x%x bestArm 0x%x "
1338			"io_info->span_arm 0x%x\n",
1339			span, arm, bestArm, io_info->span_arm);
1340#endif
1341	return io_info->pd_after_lb;
1342}
1343
1344u16 get_updated_dev_handle(struct megasas_instance *instance,
1345	struct LD_LOAD_BALANCE_INFO *lbInfo, struct IO_REQUEST_INFO *io_info)
1346{
1347	u8 arm_pd;
1348	u16 devHandle;
1349	struct fusion_context *fusion;
1350	struct MR_DRV_RAID_MAP_ALL *drv_map;
1351
1352	fusion = instance->ctrl_context;
1353	drv_map = fusion->ld_drv_map[(instance->map_id & 1)];
1354
1355	/* get best new arm (PD ID) */
1356	arm_pd  = megasas_get_best_arm_pd(instance, lbInfo, io_info);
1357	devHandle = MR_PdDevHandleGet(arm_pd, drv_map);
1358	atomic_inc(&lbInfo->scsi_pending_cmds[arm_pd]);
1359	return devHandle;
1360}
1361