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
70#ifdef FALSE
71#undef FALSE
72#endif
73#define FALSE 0
74
75#ifdef TRUE
76#undef TRUE
77#endif
78#define TRUE 1
79
80#define SPAN_DEBUG 0
81#define SPAN_ROW_SIZE(map, ld, index_) (MR_LdSpanPtrGet(ld, index_, map)->spanRowSize)
82#define SPAN_ROW_DATA_SIZE(map_, ld, index_)   (MR_LdSpanPtrGet(ld, index_, map)->spanRowDataSize)
83#define SPAN_INVALID  0xff
84
85/* Prototypes */
86static void mr_update_span_set(struct MR_DRV_RAID_MAP_ALL *map,
87	PLD_SPAN_INFO ldSpanInfo);
88static u8 mr_spanset_get_phy_params(struct megasas_instance *instance, u32 ld,
89	u64 stripRow, u16 stripRef, struct IO_REQUEST_INFO *io_info,
90	struct RAID_CONTEXT *pRAID_Context, struct MR_DRV_RAID_MAP_ALL *map);
91static u64 get_row_from_strip(struct megasas_instance *instance, u32 ld,
92	u64 strip, struct MR_DRV_RAID_MAP_ALL *map);
93
94u32 mega_mod64(u64 dividend, u32 divisor)
95{
96	u64 d;
97	u32 remainder;
98
99	if (!divisor)
100		printk(KERN_ERR "megasas : DIVISOR is zero, in div fn\n");
101	d = dividend;
102	remainder = do_div(d, divisor);
103	return remainder;
104}
105
106/**
107 * @param dividend    : Dividend
108 * @param divisor    : Divisor
109 *
110 * @return quotient
111 **/
112u64 mega_div64_32(uint64_t dividend, uint32_t divisor)
113{
114	u32 remainder;
115	u64 d;
116
117	if (!divisor)
118		printk(KERN_ERR "megasas : DIVISOR is zero in mod fn\n");
119
120	d = dividend;
121	remainder = do_div(d, divisor);
122
123	return d;
124}
125
126struct MR_LD_RAID *MR_LdRaidGet(u32 ld, struct MR_DRV_RAID_MAP_ALL *map)
127{
128	return &map->raidMap.ldSpanMap[ld].ldRaid;
129}
130
131static struct MR_SPAN_BLOCK_INFO *MR_LdSpanInfoGet(u32 ld,
132						   struct MR_DRV_RAID_MAP_ALL
133						   *map)
134{
135	return &map->raidMap.ldSpanMap[ld].spanBlock[0];
136}
137
138static u8 MR_LdDataArmGet(u32 ld, u32 armIdx, struct MR_DRV_RAID_MAP_ALL *map)
139{
140	return map->raidMap.ldSpanMap[ld].dataArmMap[armIdx];
141}
142
143u16 MR_ArPdGet(u32 ar, u32 arm, struct MR_DRV_RAID_MAP_ALL *map)
144{
145	return le16_to_cpu(map->raidMap.arMapInfo[ar].pd[arm]);
146}
147
148u16 MR_LdSpanArrayGet(u32 ld, u32 span, struct MR_DRV_RAID_MAP_ALL *map)
149{
150	return le16_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].span.arrayRef);
151}
152
153__le16 MR_PdDevHandleGet(u32 pd, struct MR_DRV_RAID_MAP_ALL *map)
154{
155	return map->raidMap.devHndlInfo[pd].curDevHdl;
156}
157
158u16 MR_GetLDTgtId(u32 ld, struct MR_DRV_RAID_MAP_ALL *map)
159{
160	return le16_to_cpu(map->raidMap.ldSpanMap[ld].ldRaid.targetId);
161}
162
163u8 MR_TargetIdToLdGet(u32 ldTgtId, struct MR_DRV_RAID_MAP_ALL *map)
164{
165	return map->raidMap.ldTgtIdToLd[ldTgtId];
166}
167
168static struct MR_LD_SPAN *MR_LdSpanPtrGet(u32 ld, u32 span,
169					  struct MR_DRV_RAID_MAP_ALL *map)
170{
171	return &map->raidMap.ldSpanMap[ld].spanBlock[span].span;
172}
173
174/*
175 * This function will Populate Driver Map using firmware raid map
176 */
177void MR_PopulateDrvRaidMap(struct megasas_instance *instance)
178{
179	struct fusion_context *fusion = instance->ctrl_context;
180	struct MR_FW_RAID_MAP_ALL     *fw_map_old    = NULL;
181	struct MR_FW_RAID_MAP         *pFwRaidMap    = NULL;
182	int i;
183	u16 ld_count;
184
185
186	struct MR_DRV_RAID_MAP_ALL *drv_map =
187			fusion->ld_drv_map[(instance->map_id & 1)];
188	struct MR_DRV_RAID_MAP *pDrvRaidMap = &drv_map->raidMap;
189
190	if (instance->supportmax256vd) {
191		memcpy(fusion->ld_drv_map[instance->map_id & 1],
192			fusion->ld_map[instance->map_id & 1],
193			fusion->current_map_sz);
194		/* New Raid map will not set totalSize, so keep expected value
195		 * for legacy code in ValidateMapInfo
196		 */
197		pDrvRaidMap->totalSize =
198			cpu_to_le32(sizeof(struct MR_FW_RAID_MAP_EXT));
199	} else {
200		fw_map_old = (struct MR_FW_RAID_MAP_ALL *)
201			fusion->ld_map[(instance->map_id & 1)];
202		pFwRaidMap = &fw_map_old->raidMap;
203		ld_count = (u16)le32_to_cpu(pFwRaidMap->ldCount);
204
205#if VD_EXT_DEBUG
206		for (i = 0; i < ld_count; i++) {
207			dev_dbg(&instance->pdev->dev, "(%d) :Index 0x%x "
208				"Target Id 0x%x Seq Num 0x%x Size 0/%llx\n",
209				instance->unique_id, i,
210				fw_map_old->raidMap.ldSpanMap[i].ldRaid.targetId,
211				fw_map_old->raidMap.ldSpanMap[i].ldRaid.seqNum,
212				fw_map_old->raidMap.ldSpanMap[i].ldRaid.size);
213		}
214#endif
215
216		memset(drv_map, 0, fusion->drv_map_sz);
217		pDrvRaidMap->totalSize = pFwRaidMap->totalSize;
218		pDrvRaidMap->ldCount = (__le16)cpu_to_le16(ld_count);
219		pDrvRaidMap->fpPdIoTimeoutSec = pFwRaidMap->fpPdIoTimeoutSec;
220		for (i = 0; i < MAX_RAIDMAP_LOGICAL_DRIVES + MAX_RAIDMAP_VIEWS; i++)
221			pDrvRaidMap->ldTgtIdToLd[i] =
222				(u8)pFwRaidMap->ldTgtIdToLd[i];
223		for (i = (MAX_RAIDMAP_LOGICAL_DRIVES + MAX_RAIDMAP_VIEWS);
224			i < MAX_LOGICAL_DRIVES_EXT; i++)
225			pDrvRaidMap->ldTgtIdToLd[i] = 0xff;
226		for (i = 0; i < ld_count; i++) {
227			pDrvRaidMap->ldSpanMap[i] = pFwRaidMap->ldSpanMap[i];
228#if VD_EXT_DEBUG
229			dev_dbg(&instance->pdev->dev,
230				"pFwRaidMap->ldSpanMap[%d].ldRaid.targetId 0x%x "
231				"pFwRaidMap->ldSpanMap[%d].ldRaid.seqNum 0x%x "
232				"size 0x%x\n", i, i,
233				pFwRaidMap->ldSpanMap[i].ldRaid.targetId,
234				pFwRaidMap->ldSpanMap[i].ldRaid.seqNum,
235				(u32)pFwRaidMap->ldSpanMap[i].ldRaid.rowSize);
236			dev_dbg(&instance->pdev->dev,
237				"pDrvRaidMap->ldSpanMap[%d].ldRaid.targetId 0x%x "
238				"pDrvRaidMap->ldSpanMap[%d].ldRaid.seqNum 0x%x "
239				"size 0x%x\n", i, i,
240				pDrvRaidMap->ldSpanMap[i].ldRaid.targetId,
241				pDrvRaidMap->ldSpanMap[i].ldRaid.seqNum,
242				(u32)pDrvRaidMap->ldSpanMap[i].ldRaid.rowSize);
243			dev_dbg(&instance->pdev->dev, "Driver raid map all %p "
244				"raid map %p LD RAID MAP %p/%p\n", drv_map,
245				pDrvRaidMap, &pFwRaidMap->ldSpanMap[i].ldRaid,
246				&pDrvRaidMap->ldSpanMap[i].ldRaid);
247#endif
248		}
249		memcpy(pDrvRaidMap->arMapInfo, pFwRaidMap->arMapInfo,
250			sizeof(struct MR_ARRAY_INFO) * MAX_RAIDMAP_ARRAYS);
251		memcpy(pDrvRaidMap->devHndlInfo, pFwRaidMap->devHndlInfo,
252			sizeof(struct MR_DEV_HANDLE_INFO) *
253			MAX_RAIDMAP_PHYSICAL_DEVICES);
254	}
255}
256
257/*
258 * This function will validate Map info data provided by FW
259 */
260u8 MR_ValidateMapInfo(struct megasas_instance *instance)
261{
262	struct fusion_context *fusion;
263	struct MR_DRV_RAID_MAP_ALL *drv_map;
264	struct MR_DRV_RAID_MAP *pDrvRaidMap;
265	struct LD_LOAD_BALANCE_INFO *lbInfo;
266	PLD_SPAN_INFO ldSpanInfo;
267	struct MR_LD_RAID         *raid;
268	u16 ldCount, num_lds;
269	u16 ld;
270	u32 expected_size;
271
272
273	MR_PopulateDrvRaidMap(instance);
274
275	fusion = instance->ctrl_context;
276	drv_map = fusion->ld_drv_map[(instance->map_id & 1)];
277	pDrvRaidMap = &drv_map->raidMap;
278
279	lbInfo = fusion->load_balance_info;
280	ldSpanInfo = fusion->log_to_span;
281
282	if (instance->supportmax256vd)
283		expected_size = sizeof(struct MR_FW_RAID_MAP_EXT);
284	else
285		expected_size =
286			(sizeof(struct MR_FW_RAID_MAP) - sizeof(struct MR_LD_SPAN_MAP) +
287			(sizeof(struct MR_LD_SPAN_MAP) * le16_to_cpu(pDrvRaidMap->ldCount)));
288
289	if (le32_to_cpu(pDrvRaidMap->totalSize) != expected_size) {
290		dev_err(&instance->pdev->dev, "map info structure size 0x%x is not matching with ld count\n",
291		       (unsigned int) expected_size);
292		dev_err(&instance->pdev->dev, "megasas: span map %x, pDrvRaidMap->totalSize : %x\n",
293			(unsigned int)sizeof(struct MR_LD_SPAN_MAP),
294			le32_to_cpu(pDrvRaidMap->totalSize));
295		return 0;
296	}
297
298	if (instance->UnevenSpanSupport)
299		mr_update_span_set(drv_map, ldSpanInfo);
300
301	mr_update_load_balance_params(drv_map, lbInfo);
302
303	num_lds = le16_to_cpu(drv_map->raidMap.ldCount);
304
305	/*Convert Raid capability values to CPU arch */
306	for (ldCount = 0; ldCount < num_lds; ldCount++) {
307		ld = MR_TargetIdToLdGet(ldCount, drv_map);
308		raid = MR_LdRaidGet(ld, drv_map);
309		le32_to_cpus((u32 *)&raid->capability);
310	}
311
312	return 1;
313}
314
315u32 MR_GetSpanBlock(u32 ld, u64 row, u64 *span_blk,
316		    struct MR_DRV_RAID_MAP_ALL *map)
317{
318	struct MR_SPAN_BLOCK_INFO *pSpanBlock = MR_LdSpanInfoGet(ld, map);
319	struct MR_QUAD_ELEMENT    *quad;
320	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
321	u32                span, j;
322
323	for (span = 0; span < raid->spanDepth; span++, pSpanBlock++) {
324
325		for (j = 0; j < le32_to_cpu(pSpanBlock->block_span_info.noElements); j++) {
326			quad = &pSpanBlock->block_span_info.quad[j];
327
328			if (le32_to_cpu(quad->diff) == 0)
329				return SPAN_INVALID;
330			if (le64_to_cpu(quad->logStart) <= row && row <=
331				le64_to_cpu(quad->logEnd) && (mega_mod64(row - le64_to_cpu(quad->logStart),
332				le32_to_cpu(quad->diff))) == 0) {
333				if (span_blk != NULL) {
334					u64  blk, debugBlk;
335					blk =  mega_div64_32((row-le64_to_cpu(quad->logStart)), le32_to_cpu(quad->diff));
336					debugBlk = blk;
337
338					blk = (blk + le64_to_cpu(quad->offsetInSpan)) << raid->stripeShift;
339					*span_blk = blk;
340				}
341				return span;
342			}
343		}
344	}
345	return SPAN_INVALID;
346}
347
348/*
349******************************************************************************
350*
351* Function to print info about span set created in driver from FW raid map
352*
353* Inputs :
354* map    - LD map
355* ldSpanInfo - ldSpanInfo per HBA instance
356*/
357#if SPAN_DEBUG
358static int getSpanInfo(struct MR_DRV_RAID_MAP_ALL *map,
359	PLD_SPAN_INFO ldSpanInfo)
360{
361
362	u8   span;
363	u32    element;
364	struct MR_LD_RAID *raid;
365	LD_SPAN_SET *span_set;
366	struct MR_QUAD_ELEMENT    *quad;
367	int ldCount;
368	u16 ld;
369
370	for (ldCount = 0; ldCount < MAX_LOGICAL_DRIVES_EXT; ldCount++) {
371		ld = MR_TargetIdToLdGet(ldCount, map);
372			if (ld >= (MAX_LOGICAL_DRIVES_EXT - 1))
373				continue;
374		raid = MR_LdRaidGet(ld, map);
375		dev_dbg(&instance->pdev->dev, "LD %x: span_depth=%x\n",
376			ld, raid->spanDepth);
377		for (span = 0; span < raid->spanDepth; span++)
378			dev_dbg(&instance->pdev->dev, "Span=%x,"
379			" number of quads=%x\n", span,
380			le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
381			block_span_info.noElements));
382		for (element = 0; element < MAX_QUAD_DEPTH; element++) {
383			span_set = &(ldSpanInfo[ld].span_set[element]);
384			if (span_set->span_row_data_width == 0)
385				break;
386
387			dev_dbg(&instance->pdev->dev, "Span Set %x:"
388				"width=%x, diff=%x\n", element,
389				(unsigned int)span_set->span_row_data_width,
390				(unsigned int)span_set->diff);
391			dev_dbg(&instance->pdev->dev, "logical LBA"
392				"start=0x%08lx, end=0x%08lx\n",
393				(long unsigned int)span_set->log_start_lba,
394				(long unsigned int)span_set->log_end_lba);
395			dev_dbg(&instance->pdev->dev, "span row start=0x%08lx,"
396				" end=0x%08lx\n",
397				(long unsigned int)span_set->span_row_start,
398				(long unsigned int)span_set->span_row_end);
399			dev_dbg(&instance->pdev->dev, "data row start=0x%08lx,"
400				" end=0x%08lx\n",
401				(long unsigned int)span_set->data_row_start,
402				(long unsigned int)span_set->data_row_end);
403			dev_dbg(&instance->pdev->dev, "data strip start=0x%08lx,"
404				" end=0x%08lx\n",
405				(long unsigned int)span_set->data_strip_start,
406				(long unsigned int)span_set->data_strip_end);
407
408			for (span = 0; span < raid->spanDepth; span++) {
409				if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
410					block_span_info.noElements) >=
411					element + 1) {
412					quad = &map->raidMap.ldSpanMap[ld].
413						spanBlock[span].block_span_info.
414						quad[element];
415				dev_dbg(&instance->pdev->dev, "Span=%x,"
416					"Quad=%x, diff=%x\n", span,
417					element, le32_to_cpu(quad->diff));
418				dev_dbg(&instance->pdev->dev,
419					"offset_in_span=0x%08lx\n",
420					(long unsigned int)le64_to_cpu(quad->offsetInSpan));
421				dev_dbg(&instance->pdev->dev,
422					"logical start=0x%08lx, end=0x%08lx\n",
423					(long unsigned int)le64_to_cpu(quad->logStart),
424					(long unsigned int)le64_to_cpu(quad->logEnd));
425				}
426			}
427		}
428	}
429	return 0;
430}
431#endif
432
433/*
434******************************************************************************
435*
436* This routine calculates the Span block for given row using spanset.
437*
438* Inputs :
439*    instance - HBA instance
440*    ld   - Logical drive number
441*    row        - Row number
442*    map    - LD map
443*
444* Outputs :
445*
446*    span          - Span number
447*    block         - Absolute Block number in the physical disk
448*    div_error	   - Devide error code.
449*/
450
451u32 mr_spanset_get_span_block(struct megasas_instance *instance,
452		u32 ld, u64 row, u64 *span_blk, struct MR_DRV_RAID_MAP_ALL *map)
453{
454	struct fusion_context *fusion = instance->ctrl_context;
455	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
456	LD_SPAN_SET *span_set;
457	struct MR_QUAD_ELEMENT    *quad;
458	u32    span, info;
459	PLD_SPAN_INFO ldSpanInfo = fusion->log_to_span;
460
461	for (info = 0; info < MAX_QUAD_DEPTH; info++) {
462		span_set = &(ldSpanInfo[ld].span_set[info]);
463
464		if (span_set->span_row_data_width == 0)
465			break;
466
467		if (row > span_set->data_row_end)
468			continue;
469
470		for (span = 0; span < raid->spanDepth; span++)
471			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
472				block_span_info.noElements) >= info+1) {
473				quad = &map->raidMap.ldSpanMap[ld].
474					spanBlock[span].
475					block_span_info.quad[info];
476				if (le32_to_cpu(quad->diff) == 0)
477					return SPAN_INVALID;
478				if (le64_to_cpu(quad->logStart) <= row  &&
479					row <= le64_to_cpu(quad->logEnd)  &&
480					(mega_mod64(row - le64_to_cpu(quad->logStart),
481						le32_to_cpu(quad->diff))) == 0) {
482					if (span_blk != NULL) {
483						u64  blk;
484						blk = mega_div64_32
485						    ((row - le64_to_cpu(quad->logStart)),
486						    le32_to_cpu(quad->diff));
487						blk = (blk + le64_to_cpu(quad->offsetInSpan))
488							 << raid->stripeShift;
489						*span_blk = blk;
490					}
491					return span;
492				}
493			}
494	}
495	return SPAN_INVALID;
496}
497
498/*
499******************************************************************************
500*
501* This routine calculates the row for given strip using spanset.
502*
503* Inputs :
504*    instance - HBA instance
505*    ld   - Logical drive number
506*    Strip        - Strip
507*    map    - LD map
508*
509* Outputs :
510*
511*    row         - row associated with strip
512*/
513
514static u64  get_row_from_strip(struct megasas_instance *instance,
515	u32 ld, u64 strip, struct MR_DRV_RAID_MAP_ALL *map)
516{
517	struct fusion_context *fusion = instance->ctrl_context;
518	struct MR_LD_RAID	*raid = MR_LdRaidGet(ld, map);
519	LD_SPAN_SET	*span_set;
520	PLD_SPAN_INFO	ldSpanInfo = fusion->log_to_span;
521	u32		info, strip_offset, span, span_offset;
522	u64		span_set_Strip, span_set_Row, retval;
523
524	for (info = 0; info < MAX_QUAD_DEPTH; info++) {
525		span_set = &(ldSpanInfo[ld].span_set[info]);
526
527		if (span_set->span_row_data_width == 0)
528			break;
529		if (strip > span_set->data_strip_end)
530			continue;
531
532		span_set_Strip = strip - span_set->data_strip_start;
533		strip_offset = mega_mod64(span_set_Strip,
534				span_set->span_row_data_width);
535		span_set_Row = mega_div64_32(span_set_Strip,
536				span_set->span_row_data_width) * span_set->diff;
537		for (span = 0, span_offset = 0; span < raid->spanDepth; span++)
538			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
539				block_span_info.noElements) >= info+1) {
540				if (strip_offset >=
541					span_set->strip_offset[span])
542					span_offset++;
543				else
544					break;
545			}
546#if SPAN_DEBUG
547		dev_info(&instance->pdev->dev, "Strip 0x%llx,"
548			"span_set_Strip 0x%llx, span_set_Row 0x%llx"
549			"data width 0x%llx span offset 0x%x\n", strip,
550			(unsigned long long)span_set_Strip,
551			(unsigned long long)span_set_Row,
552			(unsigned long long)span_set->span_row_data_width,
553			span_offset);
554		dev_info(&instance->pdev->dev, "For strip 0x%llx"
555			"row is 0x%llx\n", strip,
556			(unsigned long long) span_set->data_row_start +
557			(unsigned long long) span_set_Row + (span_offset - 1));
558#endif
559		retval = (span_set->data_row_start + span_set_Row +
560				(span_offset - 1));
561		return retval;
562	}
563	return -1LLU;
564}
565
566
567/*
568******************************************************************************
569*
570* This routine calculates the Start Strip for given row using spanset.
571*
572* Inputs :
573*    instance - HBA instance
574*    ld   - Logical drive number
575*    row        - Row number
576*    map    - LD map
577*
578* Outputs :
579*
580*    Strip         - Start strip associated with row
581*/
582
583static u64 get_strip_from_row(struct megasas_instance *instance,
584		u32 ld, u64 row, struct MR_DRV_RAID_MAP_ALL *map)
585{
586	struct fusion_context *fusion = instance->ctrl_context;
587	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
588	LD_SPAN_SET *span_set;
589	struct MR_QUAD_ELEMENT    *quad;
590	PLD_SPAN_INFO ldSpanInfo = fusion->log_to_span;
591	u32    span, info;
592	u64  strip;
593
594	for (info = 0; info < MAX_QUAD_DEPTH; info++) {
595		span_set = &(ldSpanInfo[ld].span_set[info]);
596
597		if (span_set->span_row_data_width == 0)
598			break;
599		if (row > span_set->data_row_end)
600			continue;
601
602		for (span = 0; span < raid->spanDepth; span++)
603			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
604				block_span_info.noElements) >= info+1) {
605				quad = &map->raidMap.ldSpanMap[ld].
606					spanBlock[span].block_span_info.quad[info];
607				if (le64_to_cpu(quad->logStart) <= row  &&
608					row <= le64_to_cpu(quad->logEnd)  &&
609					mega_mod64((row - le64_to_cpu(quad->logStart)),
610					le32_to_cpu(quad->diff)) == 0) {
611					strip = mega_div64_32
612						(((row - span_set->data_row_start)
613							- le64_to_cpu(quad->logStart)),
614							le32_to_cpu(quad->diff));
615					strip *= span_set->span_row_data_width;
616					strip += span_set->data_strip_start;
617					strip += span_set->strip_offset[span];
618					return strip;
619				}
620			}
621	}
622	dev_err(&instance->pdev->dev, "get_strip_from_row"
623		"returns invalid strip for ld=%x, row=%lx\n",
624		ld, (long unsigned int)row);
625	return -1;
626}
627
628/*
629******************************************************************************
630*
631* This routine calculates the Physical Arm for given strip using spanset.
632*
633* Inputs :
634*    instance - HBA instance
635*    ld   - Logical drive number
636*    strip      - Strip
637*    map    - LD map
638*
639* Outputs :
640*
641*    Phys Arm         - Phys Arm associated with strip
642*/
643
644static u32 get_arm_from_strip(struct megasas_instance *instance,
645	u32 ld, u64 strip, struct MR_DRV_RAID_MAP_ALL *map)
646{
647	struct fusion_context *fusion = instance->ctrl_context;
648	struct MR_LD_RAID         *raid = MR_LdRaidGet(ld, map);
649	LD_SPAN_SET *span_set;
650	PLD_SPAN_INFO ldSpanInfo = fusion->log_to_span;
651	u32    info, strip_offset, span, span_offset, retval;
652
653	for (info = 0 ; info < MAX_QUAD_DEPTH; info++) {
654		span_set = &(ldSpanInfo[ld].span_set[info]);
655
656		if (span_set->span_row_data_width == 0)
657			break;
658		if (strip > span_set->data_strip_end)
659			continue;
660
661		strip_offset = (uint)mega_mod64
662				((strip - span_set->data_strip_start),
663				span_set->span_row_data_width);
664
665		for (span = 0, span_offset = 0; span < raid->spanDepth; span++)
666			if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
667				block_span_info.noElements) >= info+1) {
668				if (strip_offset >=
669					span_set->strip_offset[span])
670					span_offset =
671						span_set->strip_offset[span];
672				else
673					break;
674			}
675#if SPAN_DEBUG
676		dev_info(&instance->pdev->dev, "get_arm_from_strip:"
677			"for ld=0x%x strip=0x%lx arm is  0x%x\n", ld,
678			(long unsigned int)strip, (strip_offset - span_offset));
679#endif
680		retval = (strip_offset - span_offset);
681		return retval;
682	}
683
684	dev_err(&instance->pdev->dev, "get_arm_from_strip"
685		"returns invalid arm for ld=%x strip=%lx\n",
686		ld, (long unsigned int)strip);
687
688	return -1;
689}
690
691/* This Function will return Phys arm */
692u8 get_arm(struct megasas_instance *instance, u32 ld, u8 span, u64 stripe,
693		struct MR_DRV_RAID_MAP_ALL *map)
694{
695	struct MR_LD_RAID  *raid = MR_LdRaidGet(ld, map);
696	/* Need to check correct default value */
697	u32    arm = 0;
698
699	switch (raid->level) {
700	case 0:
701	case 5:
702	case 6:
703		arm = mega_mod64(stripe, SPAN_ROW_SIZE(map, ld, span));
704		break;
705	case 1:
706		/* start with logical arm */
707		arm = get_arm_from_strip(instance, ld, stripe, map);
708		if (arm != -1U)
709			arm *= 2;
710		break;
711	}
712
713	return arm;
714}
715
716
717/*
718******************************************************************************
719*
720* This routine calculates the arm, span and block for the specified stripe and
721* reference in stripe using spanset
722*
723* Inputs :
724*
725*    ld   - Logical drive number
726*    stripRow        - Stripe number
727*    stripRef    - Reference in stripe
728*
729* Outputs :
730*
731*    span          - Span number
732*    block         - Absolute Block number in the physical disk
733*/
734static u8 mr_spanset_get_phy_params(struct megasas_instance *instance, u32 ld,
735		u64 stripRow, u16 stripRef, struct IO_REQUEST_INFO *io_info,
736		struct RAID_CONTEXT *pRAID_Context,
737		struct MR_DRV_RAID_MAP_ALL *map)
738{
739	struct MR_LD_RAID  *raid = MR_LdRaidGet(ld, map);
740	u32     pd, arRef;
741	u8      physArm, span;
742	u64     row;
743	u8	retval = TRUE;
744	u64	*pdBlock = &io_info->pdBlock;
745	__le16	*pDevHandle = &io_info->devHandle;
746	u32	logArm, rowMod, armQ, arm;
747	struct fusion_context *fusion;
748
749	fusion = instance->ctrl_context;
750
751	/*Get row and span from io_info for Uneven Span IO.*/
752	row	    = io_info->start_row;
753	span	    = io_info->start_span;
754
755
756	if (raid->level == 6) {
757		logArm = get_arm_from_strip(instance, ld, stripRow, map);
758		if (logArm == -1U)
759			return FALSE;
760		rowMod = mega_mod64(row, SPAN_ROW_SIZE(map, ld, span));
761		armQ = SPAN_ROW_SIZE(map, ld, span) - 1 - rowMod;
762		arm = armQ + 1 + logArm;
763		if (arm >= SPAN_ROW_SIZE(map, ld, span))
764			arm -= SPAN_ROW_SIZE(map, ld, span);
765		physArm = (u8)arm;
766	} else
767		/* Calculate the arm */
768		physArm = get_arm(instance, ld, span, stripRow, map);
769	if (physArm == 0xFF)
770		return FALSE;
771
772	arRef       = MR_LdSpanArrayGet(ld, span, map);
773	pd          = MR_ArPdGet(arRef, physArm, map);
774
775	if (pd != MR_PD_INVALID)
776		*pDevHandle = MR_PdDevHandleGet(pd, map);
777	else {
778		*pDevHandle = cpu_to_le16(MR_PD_INVALID);
779		if ((raid->level >= 5) &&
780			((fusion->adapter_type == THUNDERBOLT_SERIES)  ||
781			((fusion->adapter_type == INVADER_SERIES) &&
782			(raid->regTypeReqOnRead != REGION_TYPE_UNUSED))))
783			pRAID_Context->regLockFlags = REGION_TYPE_EXCLUSIVE;
784		else if (raid->level == 1) {
785			pd = MR_ArPdGet(arRef, physArm + 1, map);
786			if (pd != MR_PD_INVALID)
787				*pDevHandle = MR_PdDevHandleGet(pd, map);
788		}
789	}
790
791	*pdBlock += stripRef + le64_to_cpu(MR_LdSpanPtrGet(ld, span, map)->startBlk);
792	pRAID_Context->spanArm = (span << RAID_CTX_SPANARM_SPAN_SHIFT) |
793					physArm;
794	io_info->span_arm = pRAID_Context->spanArm;
795	return retval;
796}
797
798/*
799******************************************************************************
800*
801* This routine calculates the arm, span and block for the specified stripe and
802* reference in stripe.
803*
804* Inputs :
805*
806*    ld   - Logical drive number
807*    stripRow        - Stripe number
808*    stripRef    - Reference in stripe
809*
810* Outputs :
811*
812*    span          - Span number
813*    block         - Absolute Block number in the physical disk
814*/
815u8 MR_GetPhyParams(struct megasas_instance *instance, u32 ld, u64 stripRow,
816		u16 stripRef, struct IO_REQUEST_INFO *io_info,
817		struct RAID_CONTEXT *pRAID_Context,
818		struct MR_DRV_RAID_MAP_ALL *map)
819{
820	struct MR_LD_RAID  *raid = MR_LdRaidGet(ld, map);
821	u32         pd, arRef;
822	u8          physArm, span;
823	u64         row;
824	u8	    retval = TRUE;
825	u64	    *pdBlock = &io_info->pdBlock;
826	__le16	    *pDevHandle = &io_info->devHandle;
827	struct fusion_context *fusion;
828
829	fusion = instance->ctrl_context;
830
831
832	row =  mega_div64_32(stripRow, raid->rowDataSize);
833
834	if (raid->level == 6) {
835		/* logical arm within row */
836		u32 logArm =  mega_mod64(stripRow, raid->rowDataSize);
837		u32 rowMod, armQ, arm;
838
839		if (raid->rowSize == 0)
840			return FALSE;
841		/* get logical row mod */
842		rowMod = mega_mod64(row, raid->rowSize);
843		armQ = raid->rowSize-1-rowMod; /* index of Q drive */
844		arm = armQ+1+logArm; /* data always logically follows Q */
845		if (arm >= raid->rowSize) /* handle wrap condition */
846			arm -= raid->rowSize;
847		physArm = (u8)arm;
848	} else  {
849		if (raid->modFactor == 0)
850			return FALSE;
851		physArm = MR_LdDataArmGet(ld,  mega_mod64(stripRow,
852							  raid->modFactor),
853					  map);
854	}
855
856	if (raid->spanDepth == 1) {
857		span = 0;
858		*pdBlock = row << raid->stripeShift;
859	} else {
860		span = (u8)MR_GetSpanBlock(ld, row, pdBlock, map);
861		if (span == SPAN_INVALID)
862			return FALSE;
863	}
864
865	/* Get the array on which this span is present */
866	arRef       = MR_LdSpanArrayGet(ld, span, map);
867	pd          = MR_ArPdGet(arRef, physArm, map); /* Get the pd */
868
869	if (pd != MR_PD_INVALID)
870		/* Get dev handle from Pd. */
871		*pDevHandle = MR_PdDevHandleGet(pd, map);
872	else {
873		/* set dev handle as invalid. */
874		*pDevHandle = cpu_to_le16(MR_PD_INVALID);
875		if ((raid->level >= 5) &&
876			((fusion->adapter_type == THUNDERBOLT_SERIES)  ||
877			((fusion->adapter_type == INVADER_SERIES) &&
878			(raid->regTypeReqOnRead != REGION_TYPE_UNUSED))))
879			pRAID_Context->regLockFlags = REGION_TYPE_EXCLUSIVE;
880		else if (raid->level == 1) {
881			/* Get alternate Pd. */
882			pd = MR_ArPdGet(arRef, physArm + 1, map);
883			if (pd != MR_PD_INVALID)
884				/* Get dev handle from Pd */
885				*pDevHandle = MR_PdDevHandleGet(pd, map);
886		}
887	}
888
889	*pdBlock += stripRef + le64_to_cpu(MR_LdSpanPtrGet(ld, span, map)->startBlk);
890	pRAID_Context->spanArm = (span << RAID_CTX_SPANARM_SPAN_SHIFT) |
891		physArm;
892	io_info->span_arm = pRAID_Context->spanArm;
893	return retval;
894}
895
896/*
897******************************************************************************
898*
899* MR_BuildRaidContext function
900*
901* This function will initiate command processing.  The start/end row and strip
902* information is calculated then the lock is acquired.
903* This function will return 0 if region lock was acquired OR return num strips
904*/
905u8
906MR_BuildRaidContext(struct megasas_instance *instance,
907		    struct IO_REQUEST_INFO *io_info,
908		    struct RAID_CONTEXT *pRAID_Context,
909		    struct MR_DRV_RAID_MAP_ALL *map, u8 **raidLUN)
910{
911	struct fusion_context *fusion;
912	struct MR_LD_RAID  *raid;
913	u32         ld, stripSize, stripe_mask;
914	u64         endLba, endStrip, endRow, start_row, start_strip;
915	u64         regStart;
916	u32         regSize;
917	u8          num_strips, numRows;
918	u16         ref_in_start_stripe, ref_in_end_stripe;
919	u64         ldStartBlock;
920	u32         numBlocks, ldTgtId;
921	u8          isRead;
922	u8	    retval = 0;
923	u8	    startlba_span = SPAN_INVALID;
924	u64 *pdBlock = &io_info->pdBlock;
925
926	ldStartBlock = io_info->ldStartBlock;
927	numBlocks = io_info->numBlocks;
928	ldTgtId = io_info->ldTgtId;
929	isRead = io_info->isRead;
930	io_info->IoforUnevenSpan = 0;
931	io_info->start_span	= SPAN_INVALID;
932	fusion = instance->ctrl_context;
933
934	ld = MR_TargetIdToLdGet(ldTgtId, map);
935	raid = MR_LdRaidGet(ld, map);
936
937	/*
938	 * if rowDataSize @RAID map and spanRowDataSize @SPAN INFO are zero
939	 * return FALSE
940	 */
941	if (raid->rowDataSize == 0) {
942		if (MR_LdSpanPtrGet(ld, 0, map)->spanRowDataSize == 0)
943			return FALSE;
944		else if (instance->UnevenSpanSupport) {
945			io_info->IoforUnevenSpan = 1;
946		} else {
947			dev_info(&instance->pdev->dev,
948				"raid->rowDataSize is 0, but has SPAN[0]"
949				"rowDataSize = 0x%0x,"
950				"but there is _NO_ UnevenSpanSupport\n",
951				MR_LdSpanPtrGet(ld, 0, map)->spanRowDataSize);
952			return FALSE;
953		}
954	}
955
956	stripSize = 1 << raid->stripeShift;
957	stripe_mask = stripSize-1;
958
959
960	/*
961	 * calculate starting row and stripe, and number of strips and rows
962	 */
963	start_strip         = ldStartBlock >> raid->stripeShift;
964	ref_in_start_stripe = (u16)(ldStartBlock & stripe_mask);
965	endLba              = ldStartBlock + numBlocks - 1;
966	ref_in_end_stripe   = (u16)(endLba & stripe_mask);
967	endStrip            = endLba >> raid->stripeShift;
968	num_strips          = (u8)(endStrip - start_strip + 1); /* End strip */
969
970	if (io_info->IoforUnevenSpan) {
971		start_row = get_row_from_strip(instance, ld, start_strip, map);
972		endRow	  = get_row_from_strip(instance, ld, endStrip, map);
973		if (start_row == -1ULL || endRow == -1ULL) {
974			dev_info(&instance->pdev->dev, "return from %s %d."
975				"Send IO w/o region lock.\n",
976				__func__, __LINE__);
977			return FALSE;
978		}
979
980		if (raid->spanDepth == 1) {
981			startlba_span = 0;
982			*pdBlock = start_row << raid->stripeShift;
983		} else
984			startlba_span = (u8)mr_spanset_get_span_block(instance,
985						ld, start_row, pdBlock, map);
986		if (startlba_span == SPAN_INVALID) {
987			dev_info(&instance->pdev->dev, "return from %s %d"
988				"for row 0x%llx,start strip %llx"
989				"endSrip %llx\n", __func__, __LINE__,
990				(unsigned long long)start_row,
991				(unsigned long long)start_strip,
992				(unsigned long long)endStrip);
993			return FALSE;
994		}
995		io_info->start_span	= startlba_span;
996		io_info->start_row	= start_row;
997#if SPAN_DEBUG
998		dev_dbg(&instance->pdev->dev, "Check Span number from %s %d"
999			"for row 0x%llx, start strip 0x%llx end strip 0x%llx"
1000			" span 0x%x\n", __func__, __LINE__,
1001			(unsigned long long)start_row,
1002			(unsigned long long)start_strip,
1003			(unsigned long long)endStrip, startlba_span);
1004		dev_dbg(&instance->pdev->dev, "start_row 0x%llx endRow 0x%llx"
1005			"Start span 0x%x\n", (unsigned long long)start_row,
1006			(unsigned long long)endRow, startlba_span);
1007#endif
1008	} else {
1009		start_row = mega_div64_32(start_strip, raid->rowDataSize);
1010		endRow    = mega_div64_32(endStrip, raid->rowDataSize);
1011	}
1012	numRows = (u8)(endRow - start_row + 1);
1013
1014	/*
1015	 * calculate region info.
1016	 */
1017
1018	/* assume region is at the start of the first row */
1019	regStart            = start_row << raid->stripeShift;
1020	/* assume this IO needs the full row - we'll adjust if not true */
1021	regSize             = stripSize;
1022
1023	/* Check if we can send this I/O via FastPath */
1024	if (raid->capability.fpCapable) {
1025		if (isRead)
1026			io_info->fpOkForIo = (raid->capability.fpReadCapable &&
1027					      ((num_strips == 1) ||
1028					       raid->capability.
1029					       fpReadAcrossStripe));
1030		else
1031			io_info->fpOkForIo = (raid->capability.fpWriteCapable &&
1032					      ((num_strips == 1) ||
1033					       raid->capability.
1034					       fpWriteAcrossStripe));
1035	} else
1036		io_info->fpOkForIo = FALSE;
1037
1038	if (numRows == 1) {
1039		/* single-strip IOs can always lock only the data needed */
1040		if (num_strips == 1) {
1041			regStart += ref_in_start_stripe;
1042			regSize = numBlocks;
1043		}
1044		/* multi-strip IOs always need to full stripe locked */
1045	} else if (io_info->IoforUnevenSpan == 0) {
1046		/*
1047		 * For Even span region lock optimization.
1048		 * If the start strip is the last in the start row
1049		 */
1050		if (start_strip == (start_row + 1) * raid->rowDataSize - 1) {
1051			regStart += ref_in_start_stripe;
1052			/* initialize count to sectors from startref to end
1053			   of strip */
1054			regSize = stripSize - ref_in_start_stripe;
1055		}
1056
1057		/* add complete rows in the middle of the transfer */
1058		if (numRows > 2)
1059			regSize += (numRows-2) << raid->stripeShift;
1060
1061		/* if IO ends within first strip of last row*/
1062		if (endStrip == endRow*raid->rowDataSize)
1063			regSize += ref_in_end_stripe+1;
1064		else
1065			regSize += stripSize;
1066	} else {
1067		/*
1068		 * For Uneven span region lock optimization.
1069		 * If the start strip is the last in the start row
1070		 */
1071		if (start_strip == (get_strip_from_row(instance, ld, start_row, map) +
1072				SPAN_ROW_DATA_SIZE(map, ld, startlba_span) - 1)) {
1073			regStart += ref_in_start_stripe;
1074			/* initialize count to sectors from
1075			 * startRef to end of strip
1076			 */
1077			regSize = stripSize - ref_in_start_stripe;
1078		}
1079		/* Add complete rows in the middle of the transfer*/
1080
1081		if (numRows > 2)
1082			/* Add complete rows in the middle of the transfer*/
1083			regSize += (numRows-2) << raid->stripeShift;
1084
1085		/* if IO ends within first strip of last row */
1086		if (endStrip == get_strip_from_row(instance, ld, endRow, map))
1087			regSize += ref_in_end_stripe + 1;
1088		else
1089			regSize += stripSize;
1090	}
1091
1092	pRAID_Context->timeoutValue =
1093		cpu_to_le16(raid->fpIoTimeoutForLd ?
1094			    raid->fpIoTimeoutForLd :
1095			    map->raidMap.fpPdIoTimeoutSec);
1096	if (fusion->adapter_type == INVADER_SERIES)
1097		pRAID_Context->regLockFlags = (isRead) ?
1098			raid->regTypeReqOnRead : raid->regTypeReqOnWrite;
1099	else
1100		pRAID_Context->regLockFlags = (isRead) ?
1101			REGION_TYPE_SHARED_READ : raid->regTypeReqOnWrite;
1102	pRAID_Context->VirtualDiskTgtId = raid->targetId;
1103	pRAID_Context->regLockRowLBA    = cpu_to_le64(regStart);
1104	pRAID_Context->regLockLength    = cpu_to_le32(regSize);
1105	pRAID_Context->configSeqNum	= raid->seqNum;
1106	/* save pointer to raid->LUN array */
1107	*raidLUN = raid->LUN;
1108
1109
1110	/*Get Phy Params only if FP capable, or else leave it to MR firmware
1111	  to do the calculation.*/
1112	if (io_info->fpOkForIo) {
1113		retval = io_info->IoforUnevenSpan ?
1114				mr_spanset_get_phy_params(instance, ld,
1115					start_strip, ref_in_start_stripe,
1116					io_info, pRAID_Context, map) :
1117				MR_GetPhyParams(instance, ld, start_strip,
1118					ref_in_start_stripe, io_info,
1119					pRAID_Context, map);
1120		/* If IO on an invalid Pd, then FP is not possible.*/
1121		if (io_info->devHandle == cpu_to_le16(MR_PD_INVALID))
1122			io_info->fpOkForIo = FALSE;
1123		return retval;
1124	} else if (isRead) {
1125		uint stripIdx;
1126		for (stripIdx = 0; stripIdx < num_strips; stripIdx++) {
1127			retval = io_info->IoforUnevenSpan ?
1128				mr_spanset_get_phy_params(instance, ld,
1129				    start_strip + stripIdx,
1130				    ref_in_start_stripe, io_info,
1131				    pRAID_Context, map) :
1132				MR_GetPhyParams(instance, ld,
1133				    start_strip + stripIdx, ref_in_start_stripe,
1134				    io_info, pRAID_Context, map);
1135			if (!retval)
1136				return TRUE;
1137		}
1138	}
1139
1140#if SPAN_DEBUG
1141	/* Just for testing what arm we get for strip.*/
1142	if (io_info->IoforUnevenSpan)
1143		get_arm_from_strip(instance, ld, start_strip, map);
1144#endif
1145	return TRUE;
1146}
1147
1148/*
1149******************************************************************************
1150*
1151* This routine pepare spanset info from Valid Raid map and store it into
1152* local copy of ldSpanInfo per instance data structure.
1153*
1154* Inputs :
1155* map    - LD map
1156* ldSpanInfo - ldSpanInfo per HBA instance
1157*
1158*/
1159void mr_update_span_set(struct MR_DRV_RAID_MAP_ALL *map,
1160	PLD_SPAN_INFO ldSpanInfo)
1161{
1162	u8   span, count;
1163	u32  element, span_row_width;
1164	u64  span_row;
1165	struct MR_LD_RAID *raid;
1166	LD_SPAN_SET *span_set, *span_set_prev;
1167	struct MR_QUAD_ELEMENT    *quad;
1168	int ldCount;
1169	u16 ld;
1170
1171
1172	for (ldCount = 0; ldCount < MAX_LOGICAL_DRIVES_EXT; ldCount++) {
1173		ld = MR_TargetIdToLdGet(ldCount, map);
1174		if (ld >= (MAX_LOGICAL_DRIVES_EXT - 1))
1175			continue;
1176		raid = MR_LdRaidGet(ld, map);
1177		for (element = 0; element < MAX_QUAD_DEPTH; element++) {
1178			for (span = 0; span < raid->spanDepth; span++) {
1179				if (le32_to_cpu(map->raidMap.ldSpanMap[ld].spanBlock[span].
1180					block_span_info.noElements) <
1181					element + 1)
1182					continue;
1183				span_set = &(ldSpanInfo[ld].span_set[element]);
1184				quad = &map->raidMap.ldSpanMap[ld].
1185					spanBlock[span].block_span_info.
1186					quad[element];
1187
1188				span_set->diff = le32_to_cpu(quad->diff);
1189
1190				for (count = 0, span_row_width = 0;
1191					count < raid->spanDepth; count++) {
1192					if (le32_to_cpu(map->raidMap.ldSpanMap[ld].
1193						spanBlock[count].
1194						block_span_info.
1195						noElements) >= element + 1) {
1196						span_set->strip_offset[count] =
1197							span_row_width;
1198						span_row_width +=
1199							MR_LdSpanPtrGet
1200							(ld, count, map)->spanRowDataSize;
1201					}
1202				}
1203
1204				span_set->span_row_data_width = span_row_width;
1205				span_row = mega_div64_32(((le64_to_cpu(quad->logEnd) -
1206					le64_to_cpu(quad->logStart)) + le32_to_cpu(quad->diff)),
1207					le32_to_cpu(quad->diff));
1208
1209				if (element == 0) {
1210					span_set->log_start_lba = 0;
1211					span_set->log_end_lba =
1212						((span_row << raid->stripeShift)
1213						* span_row_width) - 1;
1214
1215					span_set->span_row_start = 0;
1216					span_set->span_row_end = span_row - 1;
1217
1218					span_set->data_strip_start = 0;
1219					span_set->data_strip_end =
1220						(span_row * span_row_width) - 1;
1221
1222					span_set->data_row_start = 0;
1223					span_set->data_row_end =
1224						(span_row * le32_to_cpu(quad->diff)) - 1;
1225				} else {
1226					span_set_prev = &(ldSpanInfo[ld].
1227							span_set[element - 1]);
1228					span_set->log_start_lba =
1229						span_set_prev->log_end_lba + 1;
1230					span_set->log_end_lba =
1231						span_set->log_start_lba +
1232						((span_row << raid->stripeShift)
1233						* span_row_width) - 1;
1234
1235					span_set->span_row_start =
1236						span_set_prev->span_row_end + 1;
1237					span_set->span_row_end =
1238					span_set->span_row_start + span_row - 1;
1239
1240					span_set->data_strip_start =
1241					span_set_prev->data_strip_end + 1;
1242					span_set->data_strip_end =
1243						span_set->data_strip_start +
1244						(span_row * span_row_width) - 1;
1245
1246					span_set->data_row_start =
1247						span_set_prev->data_row_end + 1;
1248					span_set->data_row_end =
1249						span_set->data_row_start +
1250						(span_row * le32_to_cpu(quad->diff)) - 1;
1251				}
1252				break;
1253		}
1254		if (span == raid->spanDepth)
1255			break;
1256	    }
1257	}
1258#if SPAN_DEBUG
1259	getSpanInfo(map, ldSpanInfo);
1260#endif
1261
1262}
1263
1264void mr_update_load_balance_params(struct MR_DRV_RAID_MAP_ALL *drv_map,
1265	struct LD_LOAD_BALANCE_INFO *lbInfo)
1266{
1267	int ldCount;
1268	u16 ld;
1269	struct MR_LD_RAID *raid;
1270
1271	if (lb_pending_cmds > 128 || lb_pending_cmds < 1)
1272		lb_pending_cmds = LB_PENDING_CMDS_DEFAULT;
1273
1274	for (ldCount = 0; ldCount < MAX_LOGICAL_DRIVES_EXT; ldCount++) {
1275		ld = MR_TargetIdToLdGet(ldCount, drv_map);
1276		if (ld >= MAX_LOGICAL_DRIVES_EXT) {
1277			lbInfo[ldCount].loadBalanceFlag = 0;
1278			continue;
1279		}
1280
1281		raid = MR_LdRaidGet(ld, drv_map);
1282		if ((raid->level != 1) ||
1283			(raid->ldState != MR_LD_STATE_OPTIMAL)) {
1284			lbInfo[ldCount].loadBalanceFlag = 0;
1285			continue;
1286		}
1287		lbInfo[ldCount].loadBalanceFlag = 1;
1288	}
1289}
1290
1291u8 megasas_get_best_arm_pd(struct megasas_instance *instance,
1292	struct LD_LOAD_BALANCE_INFO *lbInfo, struct IO_REQUEST_INFO *io_info)
1293{
1294	struct fusion_context *fusion;
1295	struct MR_LD_RAID  *raid;
1296	struct MR_DRV_RAID_MAP_ALL *drv_map;
1297	u16     pend0, pend1, ld;
1298	u64     diff0, diff1;
1299	u8      bestArm, pd0, pd1, span, arm;
1300	u32     arRef, span_row_size;
1301
1302	u64 block = io_info->ldStartBlock;
1303	u32 count = io_info->numBlocks;
1304
1305	span = ((io_info->span_arm & RAID_CTX_SPANARM_SPAN_MASK)
1306			>> RAID_CTX_SPANARM_SPAN_SHIFT);
1307	arm = (io_info->span_arm & RAID_CTX_SPANARM_ARM_MASK);
1308
1309
1310	fusion = instance->ctrl_context;
1311	drv_map = fusion->ld_drv_map[(instance->map_id & 1)];
1312	ld = MR_TargetIdToLdGet(io_info->ldTgtId, drv_map);
1313	raid = MR_LdRaidGet(ld, drv_map);
1314	span_row_size = instance->UnevenSpanSupport ?
1315			SPAN_ROW_SIZE(drv_map, ld, span) : raid->rowSize;
1316
1317	arRef = MR_LdSpanArrayGet(ld, span, drv_map);
1318	pd0 = MR_ArPdGet(arRef, arm, drv_map);
1319	pd1 = MR_ArPdGet(arRef, (arm + 1) >= span_row_size ?
1320		(arm + 1 - span_row_size) : arm + 1, drv_map);
1321
1322	/* get the pending cmds for the data and mirror arms */
1323	pend0 = atomic_read(&lbInfo->scsi_pending_cmds[pd0]);
1324	pend1 = atomic_read(&lbInfo->scsi_pending_cmds[pd1]);
1325
1326	/* Determine the disk whose head is nearer to the req. block */
1327	diff0 = ABS_DIFF(block, lbInfo->last_accessed_block[pd0]);
1328	diff1 = ABS_DIFF(block, lbInfo->last_accessed_block[pd1]);
1329	bestArm = (diff0 <= diff1 ? arm : arm ^ 1);
1330
1331	if ((bestArm == arm && pend0 > pend1 + lb_pending_cmds)  ||
1332			(bestArm != arm && pend1 > pend0 + lb_pending_cmds))
1333		bestArm ^= 1;
1334
1335	/* Update the last accessed block on the correct pd */
1336	io_info->pd_after_lb = (bestArm == arm) ? pd0 : pd1;
1337	lbInfo->last_accessed_block[io_info->pd_after_lb] = block + count - 1;
1338	io_info->span_arm = (span << RAID_CTX_SPANARM_SPAN_SHIFT) | bestArm;
1339#if SPAN_DEBUG
1340	if (arm != bestArm)
1341		dev_dbg(&instance->pdev->dev, "LSI Debug R1 Load balance "
1342			"occur - span 0x%x arm 0x%x bestArm 0x%x "
1343			"io_info->span_arm 0x%x\n",
1344			span, arm, bestArm, io_info->span_arm);
1345#endif
1346	return io_info->pd_after_lb;
1347}
1348
1349__le16 get_updated_dev_handle(struct megasas_instance *instance,
1350	struct LD_LOAD_BALANCE_INFO *lbInfo, struct IO_REQUEST_INFO *io_info)
1351{
1352	u8 arm_pd;
1353	__le16 devHandle;
1354	struct fusion_context *fusion;
1355	struct MR_DRV_RAID_MAP_ALL *drv_map;
1356
1357	fusion = instance->ctrl_context;
1358	drv_map = fusion->ld_drv_map[(instance->map_id & 1)];
1359
1360	/* get best new arm (PD ID) */
1361	arm_pd  = megasas_get_best_arm_pd(instance, lbInfo, io_info);
1362	devHandle = MR_PdDevHandleGet(arm_pd, drv_map);
1363	atomic_inc(&lbInfo->scsi_pending_cmds[arm_pd]);
1364	return devHandle;
1365}
1366