[GitHub/mt8127/android_kernel_alcatel_ttab.git] / block / blk-merge.c

/*
 * Functions related to segment and merge handling
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/scatterlist.h>

#include "blk.h"

static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
					     struct bio *bio)
{
	struct bio_vec *bv, *bvprv = NULL;
	int cluster, i, high, highprv = 1;
	unsigned int seg_size, nr_phys_segs;
	struct bio *fbio, *bbio;

	if (!bio)
		return 0;

	fbio = bio;
	cluster = blk_queue_cluster(q);
	seg_size = 0;
	nr_phys_segs = 0;
	for_each_bio(bio) {
		bio_for_each_segment(bv, bio, i) {
			/*
			 * the trick here is making sure that a high page is
			 * never considered part of another segment, since that
			 * might change with the bounce page.
			 */
			high = page_to_pfn(bv->bv_page) > queue_bounce_pfn(q);
			if (high || highprv)
				goto new_segment;
			if (cluster) {
				if (seg_size + bv->bv_len
				    > queue_max_segment_size(q))
					goto new_segment;
				if (!BIOVEC_PHYS_MERGEABLE(bvprv, bv))
					goto new_segment;
				if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bv))
					goto new_segment;

				seg_size += bv->bv_len;
				bvprv = bv;
				continue;
			}
new_segment:
			if (nr_phys_segs == 1 && seg_size >
			    fbio->bi_seg_front_size)
				fbio->bi_seg_front_size = seg_size;

			nr_phys_segs++;
			bvprv = bv;
			seg_size = bv->bv_len;
			highprv = high;
		}
		bbio = bio;
	}

	if (nr_phys_segs == 1 && seg_size > fbio->bi_seg_front_size)
		fbio->bi_seg_front_size = seg_size;
	if (seg_size > bbio->bi_seg_back_size)
		bbio->bi_seg_back_size = seg_size;

	return nr_phys_segs;
}

void blk_recalc_rq_segments(struct request *rq)
{
	rq->nr_phys_segments = __blk_recalc_rq_segments(rq->q, rq->bio);
}

void blk_recount_segments(struct request_queue *q, struct bio *bio)
{
	struct bio *nxt = bio->bi_next;

	bio->bi_next = NULL;
	bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio);
	bio->bi_next = nxt;
	bio->bi_flags |= (1 << BIO_SEG_VALID);
}
EXPORT_SYMBOL(blk_recount_segments);

static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio,
				   struct bio *nxt)
{
	if (!blk_queue_cluster(q))
		return 0;

	if (bio->bi_seg_back_size + nxt->bi_seg_front_size >
	    queue_max_segment_size(q))
		return 0;

	if (!bio_has_data(bio))
		return 1;

	if (!BIOVEC_PHYS_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt)))
		return 0;

	/*
	 * bio and nxt are contiguous in memory; check if the queue allows
	 * these two to be merged into one
	 */
	if (BIO_SEG_BOUNDARY(q, bio, nxt))
		return 1;

	return 0;
}

static void
__blk_segment_map_sg(struct request_queue *q, struct bio_vec *bvec,
		     struct scatterlist *sglist, struct bio_vec **bvprv,
		     struct scatterlist **sg, int *nsegs, int *cluster)
{

	int nbytes = bvec->bv_len;

	if (*bvprv && *cluster) {
		if ((*sg)->length + nbytes > queue_max_segment_size(q))
			goto new_segment;

		if (!BIOVEC_PHYS_MERGEABLE(*bvprv, bvec))
			goto new_segment;
		if (!BIOVEC_SEG_BOUNDARY(q, *bvprv, bvec))
			goto new_segment;

		(*sg)->length += nbytes;
	} else {
new_segment:
		if (!*sg)
			*sg = sglist;
		else {
			/*
			 * If the driver previously mapped a shorter
			 * list, we could see a termination bit
			 * prematurely unless it fully inits the sg
			 * table on each mapping. We KNOW that there
			 * must be more entries here or the driver
			 * would be buggy, so force clear the
			 * termination bit to avoid doing a full
			 * sg_init_table() in drivers for each command.
			 */
			sg_unmark_end(*sg);
			*sg = sg_next(*sg);
		}

		sg_set_page(*sg, bvec->bv_page, nbytes, bvec->bv_offset);
		(*nsegs)++;
	}
	*bvprv = bvec;
}

/*
 * map a request to scatterlist, return number of sg entries setup. Caller
 * must make sure sg can hold rq->nr_phys_segments entries
 */
int blk_rq_map_sg(struct request_queue *q, struct request *rq,
		  struct scatterlist *sglist)
{
	struct bio_vec *bvec, *bvprv;
	struct req_iterator iter;
	struct scatterlist *sg;
	int nsegs, cluster;
#if defined(FEATURE_STORAGE_PID_LOGGER)
        struct page_pid_logger *prev_logger = 0;
#endif

	nsegs = 0;
	cluster = blk_queue_cluster(q);

	/*
	 * for each bio in rq
	 */
	bvprv = NULL;
	sg = NULL;
	rq_for_each_segment(bvec, rq, iter) {
		__blk_segment_map_sg(q, bvec, sglist, &bvprv, &sg,
				     &nsegs, &cluster);
//#undef FEATURE_STORAGE_PID_LOGGER
#if defined(FEATURE_STORAGE_PID_LOGGER)              
			do {
				extern spinlock_t g_locker;
				extern unsigned char *page_logger;
				
				extern struct struct_pid_logger g_pid_logger[PID_ID_CNT];
				unsigned long flags;
				if(page_logger) { 
					struct page_pid_logger *tmp_logger;
					unsigned long page_offset;
					int index, mmcqd_index;
					pid_t current_pid=0;
					//#if defined(CONFIG_FLATMEM)
					//page_offset = (unsigned long)((bvec->bv_page) - mem_map);
					//#else
					page_offset = (unsigned long)(__page_to_pfn(bvec->bv_page))- PHYS_PFN_OFFSET;
					//#endif
					tmp_logger =((struct page_pid_logger *)page_logger) + page_offset;
					//tmp_locker =((struct page_pid_locker *)page_logger_lock) + page_offset;
					#if defined(CONFIG_FLATMEM)
					//printk(KERN_INFO"hank merge pid1:%u pid2:%u bv_page:%p vmemmap:%p pfn:%ld %s \n", tmp_logger->pid1, tmp_logger->pid2, bvec->bv_page, vmemmap, (unsigned long)(__page_to_pfn(bvec->bv_page)), q->backing_dev_info.name);
					#else
					//printk(KERN_INFO"hank merge pid1:%u pid2:%u bv_page:%x mem_map:%x pfn:%d %s \n", tmp_logger->pid1, tmp_logger->pid2, bvec->bv_page, mem_map, (unsigned long)(__page_to_pfn(bvec->bv_page)), q->backing_dev_info.name);
					#endif
					current_pid = current->pid;

					//find the exactly pid record array
					for( mmcqd_index=0; mmcqd_index<PID_ID_CNT; mmcqd_index++) {
						//printk(KERN_INFO"hank merge mmcqd_index:%d qcurrent_pid:%d current_pid:%d", mmcqd_index, g_pid_logger[mmcqd_index].current_pid, current_pid);
						if( g_pid_logger[mmcqd_index].current_pid==0 || g_pid_logger[mmcqd_index].current_pid == current_pid ) {
							g_pid_logger[mmcqd_index].current_pid = current_pid;
							break;
						}		
					}
					//no match array
					if( mmcqd_index == PID_ID_CNT )
						break;
					/*
					if( tmp_logger->pid1 == 0XFFFF && tmp_logger->pid2 == 0XFFFF)
                                        {
                                           printk(KERN_INFO"hank merge fail offset:%d of:%d bytes:%d rw:%d", page_offset, bvec->bv_offset, nbytes, (rq->cmd_flags & REQ_WRITE));
                                        }else
                                        {
                                           printk(KERN_INFO"hank merge success offset:%d of:%d bytes:%d rw:%d", page_offset, bvec->bv_offset, nbytes, (rq->cmd_flags & REQ_WRITE));
                                        }
					*/
					if( tmp_logger->pid1 != 0xFFFF) {
						spin_lock_irqsave(&g_locker, flags);
						for( index=0; index<PID_LOGGER_COUNT; index++) {
							if( tmp_logger->pid1 == 0xFFFF)
								break;
							if( (g_pid_logger[mmcqd_index].pid_logger[index] == 0 || g_pid_logger[mmcqd_index].pid_logger[index] == tmp_logger->pid1)) {
								g_pid_logger[mmcqd_index].pid_logger[index] = tmp_logger->pid1;
								if (rq->cmd_flags & REQ_WRITE) {
									g_pid_logger[mmcqd_index].pid_logger_counter[index]++;
									g_pid_logger[mmcqd_index].pid_logger_length[index]+=bvec->bv_len;
								}else {
									g_pid_logger[mmcqd_index].pid_logger_r_counter[index]++;
									g_pid_logger[mmcqd_index].pid_logger_r_length[index]+=bvec->bv_len;
								}
								if( prev_logger && prev_logger != tmp_logger)
								   prev_logger->pid1 = 0XFFFF;
								//tmp_logger->pid1 = 0XFFFF;
								break;
							}
							
						}
						spin_unlock_irqrestore(&g_locker, flags);
					}
					if( tmp_logger->pid2 != 0xFFFF) {
						spin_lock_irqsave(&g_locker, flags);
						for( index=0; index<PID_LOGGER_COUNT; index++) {
							if( tmp_logger->pid2 == 0xFFFF)
								break;
							if( (g_pid_logger[mmcqd_index].pid_logger[index] == 0 || g_pid_logger[mmcqd_index].pid_logger[index] == tmp_logger->pid2)) {
								g_pid_logger[mmcqd_index].pid_logger[index] = tmp_logger->pid2;
								if (rq->cmd_flags & REQ_WRITE) {
									g_pid_logger[mmcqd_index].pid_logger_counter[index]++;
									g_pid_logger[mmcqd_index].pid_logger_length[index]+=bvec->bv_len;
								}else {
									g_pid_logger[mmcqd_index].pid_logger_r_counter[index]++;
									g_pid_logger[mmcqd_index].pid_logger_r_length[index]+=bvec->bv_len;
								}
								if( prev_logger && prev_logger != tmp_logger)
								   prev_logger->pid2 = 0XFFFF;
								//tmp_logger->pid2 = 0XFFFF;
								break;
							}
							
						}
						spin_unlock_irqrestore(&g_locker, flags);
					}
					prev_logger = tmp_logger;
					
				}
			} while (0);
						
#endif
	} /* segments in rq */


	if (unlikely(rq->cmd_flags & REQ_COPY_USER) &&
	    (blk_rq_bytes(rq) & q->dma_pad_mask)) {
		unsigned int pad_len =
			(q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1;

		sg->length += pad_len;
		rq->extra_len += pad_len;
	}

	if (q->dma_drain_size && q->dma_drain_needed(rq)) {
		if (rq->cmd_flags & REQ_WRITE)
			memset(q->dma_drain_buffer, 0, q->dma_drain_size);

		sg->page_link &= ~0x02;
		sg = sg_next(sg);
		sg_set_page(sg, virt_to_page(q->dma_drain_buffer),
			    q->dma_drain_size,
			    ((unsigned long)q->dma_drain_buffer) &
			    (PAGE_SIZE - 1));
		nsegs++;
		rq->extra_len += q->dma_drain_size;
	}

	if (sg)
		sg_mark_end(sg);

	return nsegs;
}
EXPORT_SYMBOL(blk_rq_map_sg);

/**
 * blk_bio_map_sg - map a bio to a scatterlist
 * @q: request_queue in question
 * @bio: bio being mapped
 * @sglist: scatterlist being mapped
 *
 * Note:
 *    Caller must make sure sg can hold bio->bi_phys_segments entries
 *
 * Will return the number of sg entries setup
 */
int blk_bio_map_sg(struct request_queue *q, struct bio *bio,
		   struct scatterlist *sglist)
{
	struct bio_vec *bvec, *bvprv;
	struct scatterlist *sg;
	int nsegs, cluster;
	unsigned long i;

	nsegs = 0;
	cluster = blk_queue_cluster(q);

	bvprv = NULL;
	sg = NULL;
	bio_for_each_segment(bvec, bio, i) {
		__blk_segment_map_sg(q, bvec, sglist, &bvprv, &sg,
				     &nsegs, &cluster);
	} /* segments in bio */

	if (sg)
		sg_mark_end(sg);

	BUG_ON(bio->bi_phys_segments && nsegs > bio->bi_phys_segments);
	return nsegs;
}
EXPORT_SYMBOL(blk_bio_map_sg);

static inline int ll_new_hw_segment(struct request_queue *q,
				    struct request *req,
				    struct bio *bio)
{
	int nr_phys_segs = bio_phys_segments(q, bio);

	if (req->nr_phys_segments + nr_phys_segs > queue_max_segments(q))
		goto no_merge;

	if (bio_integrity(bio) && blk_integrity_merge_bio(q, req, bio))
		goto no_merge;

	/*
	 * This will form the start of a new hw segment.  Bump both
	 * counters.
	 */
	req->nr_phys_segments += nr_phys_segs;
	return 1;

no_merge:
	req->cmd_flags |= REQ_NOMERGE;
	if (req == q->last_merge)
		q->last_merge = NULL;
	return 0;
}

int ll_back_merge_fn(struct request_queue *q, struct request *req,
		     struct bio *bio)
{
	if (blk_rq_sectors(req) + bio_sectors(bio) >
	    blk_rq_get_max_sectors(req)) {
		req->cmd_flags |= REQ_NOMERGE;
		if (req == q->last_merge)
			q->last_merge = NULL;
		return 0;
	}
	if (!bio_flagged(req->biotail, BIO_SEG_VALID))
		blk_recount_segments(q, req->biotail);
	if (!bio_flagged(bio, BIO_SEG_VALID))
		blk_recount_segments(q, bio);

	return ll_new_hw_segment(q, req, bio);
}

int ll_front_merge_fn(struct request_queue *q, struct request *req,
		      struct bio *bio)
{
	if (blk_rq_sectors(req) + bio_sectors(bio) >
	    blk_rq_get_max_sectors(req)) {
		req->cmd_flags |= REQ_NOMERGE;
		if (req == q->last_merge)
			q->last_merge = NULL;
		return 0;
	}
	if (!bio_flagged(bio, BIO_SEG_VALID))
		blk_recount_segments(q, bio);
	if (!bio_flagged(req->bio, BIO_SEG_VALID))
		blk_recount_segments(q, req->bio);

	return ll_new_hw_segment(q, req, bio);
}

static int ll_merge_requests_fn(struct request_queue *q, struct request *req,
				struct request *next)
{
	int total_phys_segments;
	unsigned int seg_size =
		req->biotail->bi_seg_back_size + next->bio->bi_seg_front_size;

	/*
	 * First check if the either of the requests are re-queued
	 * requests.  Can't merge them if they are.
	 */
	if (req->special || next->special)
		return 0;

	/*
	 * Will it become too large?
	 */
	if ((blk_rq_sectors(req) + blk_rq_sectors(next)) >
	    blk_rq_get_max_sectors(req))
		return 0;

	total_phys_segments = req->nr_phys_segments + next->nr_phys_segments;
	if (blk_phys_contig_segment(q, req->biotail, next->bio)) {
		if (req->nr_phys_segments == 1)
			req->bio->bi_seg_front_size = seg_size;
		if (next->nr_phys_segments == 1)
			next->biotail->bi_seg_back_size = seg_size;
		total_phys_segments--;
	}

	if (total_phys_segments > queue_max_segments(q))
		return 0;

	if (blk_integrity_rq(req) && blk_integrity_merge_rq(q, req, next))
		return 0;

	/* Merge is OK... */
	req->nr_phys_segments = total_phys_segments;
	return 1;
}

/**
 * blk_rq_set_mixed_merge - mark a request as mixed merge
 * @rq: request to mark as mixed merge
 *
 * Description:
 *     @rq is about to be mixed merged.  Make sure the attributes
 *     which can be mixed are set in each bio and mark @rq as mixed
 *     merged.
 */
void blk_rq_set_mixed_merge(struct request *rq)
{
	unsigned int ff = rq->cmd_flags & REQ_FAILFAST_MASK;
	struct bio *bio;

	if (rq->cmd_flags & REQ_MIXED_MERGE)
		return;

	/*
	 * @rq will no longer represent mixable attributes for all the
	 * contained bios.  It will just track those of the first one.
	 * Distributes the attributs to each bio.
	 */
	for (bio = rq->bio; bio; bio = bio->bi_next) {
		WARN_ON_ONCE((bio->bi_rw & REQ_FAILFAST_MASK) &&
			     (bio->bi_rw & REQ_FAILFAST_MASK) != ff);
		bio->bi_rw |= ff;
	}
	rq->cmd_flags |= REQ_MIXED_MERGE;
}

static void blk_account_io_merge(struct request *req)
{
	if (blk_do_io_stat(req)) {
		struct hd_struct *part;
		int cpu;

		cpu = part_stat_lock();
		part = req->part;

		part_round_stats(cpu, part);
		part_dec_in_flight(part, rq_data_dir(req));

		hd_struct_put(part);
		part_stat_unlock();
	}
}

/*
 * Has to be called with the request spinlock acquired
 */
static int attempt_merge(struct request_queue *q, struct request *req,
			  struct request *next)
{
	if (!rq_mergeable(req) || !rq_mergeable(next))
		return 0;

	if (!blk_check_merge_flags(req->cmd_flags, next->cmd_flags))
		return 0;

	/*
	 * not contiguous
	 */
	if (blk_rq_pos(req) + blk_rq_sectors(req) != blk_rq_pos(next))
		return 0;

	if (rq_data_dir(req) != rq_data_dir(next)
	    || req->rq_disk != next->rq_disk
	    || next->special)
		return 0;

	if (req->cmd_flags & REQ_WRITE_SAME &&
	    !blk_write_same_mergeable(req->bio, next->bio))
		return 0;

	/*
	 * If we are allowed to merge, then append bio list
	 * from next to rq and release next. merge_requests_fn
	 * will have updated segment counts, update sector
	 * counts here.
	 */
	if (!ll_merge_requests_fn(q, req, next))
		return 0;

	/*
	 * If failfast settings disagree or any of the two is already
	 * a mixed merge, mark both as mixed before proceeding.  This
	 * makes sure that all involved bios have mixable attributes
	 * set properly.
	 */
	if ((req->cmd_flags | next->cmd_flags) & REQ_MIXED_MERGE ||
	    (req->cmd_flags & REQ_FAILFAST_MASK) !=
	    (next->cmd_flags & REQ_FAILFAST_MASK)) {
		blk_rq_set_mixed_merge(req);
		blk_rq_set_mixed_merge(next);
	}

	/*
	 * At this point we have either done a back merge
	 * or front merge. We need the smaller start_time of
	 * the merged requests to be the current request
	 * for accounting purposes.
	 */
	if (time_after(req->start_time, next->start_time))
		req->start_time = next->start_time;

	req->biotail->bi_next = next->bio;
	req->biotail = next->biotail;

	req->__data_len += blk_rq_bytes(next);

	elv_merge_requests(q, req, next);

	/*
	 * 'next' is going away, so update stats accordingly
	 */
	blk_account_io_merge(next);

	req->ioprio = ioprio_best(req->ioprio, next->ioprio);
	if (blk_rq_cpu_valid(next))
		req->cpu = next->cpu;

	/* owner-ship of bio passed from next to req */
	next->bio = NULL;
	__blk_put_request(q, next);
	return 1;
}

int attempt_back_merge(struct request_queue *q, struct request *rq)
{
	struct request *next = elv_latter_request(q, rq);

	if (next)
		return attempt_merge(q, rq, next);

	return 0;
}

int attempt_front_merge(struct request_queue *q, struct request *rq)
{
	struct request *prev = elv_former_request(q, rq);

	if (prev)
		return attempt_merge(q, prev, rq);

	return 0;
}

int blk_attempt_req_merge(struct request_queue *q, struct request *rq,
			  struct request *next)
{
	return attempt_merge(q, rq, next);
}

bool blk_rq_merge_ok(struct request *rq, struct bio *bio)
{
	if (!rq_mergeable(rq) || !bio_mergeable(bio))
		return false;

	if (!blk_check_merge_flags(rq->cmd_flags, bio->bi_rw))
		return false;

	/* different data direction or already started, don't merge */
	if (bio_data_dir(bio) != rq_data_dir(rq))
		return false;

	/* must be same device and not a special request */
	if (rq->rq_disk != bio->bi_bdev->bd_disk || rq->special)
		return false;

	/* only merge integrity protected bio into ditto rq */
	if (bio_integrity(bio) != blk_integrity_rq(rq))
		return false;

	/* must be using the same buffer */
	if (rq->cmd_flags & REQ_WRITE_SAME &&
	    !blk_write_same_mergeable(rq->bio, bio))
		return false;

	return true;
}

int blk_try_merge(struct request *rq, struct bio *bio)
{
	if (blk_rq_pos(rq) + blk_rq_sectors(rq) == bio->bi_sector)
		return ELEVATOR_BACK_MERGE;
	else if (blk_rq_pos(rq) - bio_sectors(bio) == bio->bi_sector)
		return ELEVATOR_FRONT_MERGE;
	return ELEVATOR_NO_MERGE;
}
Commit	Line	Data
d6d48196 JA	1	/*
	2	* Functions related to segment and merge handling
	3	*/
	4	#include <linux/kernel.h>
	5	#include <linux/module.h>
	6	#include <linux/bio.h>
	7	#include <linux/blkdev.h>
	8	#include <linux/scatterlist.h>
	9
	10	#include "blk.h"
	11
1e428079	12	static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
59247eae	13	struct bio *bio)
d6d48196	14	{
d6d48196	15	struct bio_vec bv, bvprv = NULL;
1e428079 JA	16	int cluster, i, high, highprv = 1;
1e428079 JA	17	unsigned int seg_size, nr_phys_segs;
59247eae	18	struct bio fbio, bbio;
d6d48196	19
1e428079 JA	20	if (!bio)
1e428079 JA	21	return 0;
d6d48196	22
1e428079	23	fbio = bio;
e692cb66	24	cluster = blk_queue_cluster(q);
5df97b91	25	seg_size = 0;
2c8919de	26	nr_phys_segs = 0;
1e428079 JA	27	for_each_bio(bio) {
	28	bio_for_each_segment(bv, bio, i) {
	29	/*
	30	* the trick here is making sure that a high page is
	31	* never considered part of another segment, since that
	32	* might change with the bounce page.
	33	*/
ae03bf63	34	high = page_to_pfn(bv->bv_page) > queue_bounce_pfn(q);
1e428079	35	if (high \|\| highprv)
d6d48196	36	goto new_segment;
1e428079	37	if (cluster) {
ae03bf63 MP	38	if (seg_size + bv->bv_len
ae03bf63 MP	39	> queue_max_segment_size(q))
1e428079 JA	40	goto new_segment;
	41	if (!BIOVEC_PHYS_MERGEABLE(bvprv, bv))
	42	goto new_segment;
	43	if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bv))
	44	goto new_segment;
d6d48196	45
1e428079 JA	46	seg_size += bv->bv_len;
	47	bvprv = bv;
	48	continue;
	49	}
d6d48196	50	new_segment:
1e428079 JA	51	if (nr_phys_segs == 1 && seg_size >
	52	fbio->bi_seg_front_size)
	53	fbio->bi_seg_front_size = seg_size;
86771427	54
1e428079 JA	55	nr_phys_segs++;
	56	bvprv = bv;
	57	seg_size = bv->bv_len;
	58	highprv = high;
	59	}
59247eae	60	bbio = bio;
d6d48196 JA	61	}
d6d48196 JA	62
59247eae JA	63	if (nr_phys_segs == 1 && seg_size > fbio->bi_seg_front_size)
	64	fbio->bi_seg_front_size = seg_size;
	65	if (seg_size > bbio->bi_seg_back_size)
	66	bbio->bi_seg_back_size = seg_size;
1e428079 JA	67
	68	return nr_phys_segs;
	69	}
	70
	71	void blk_recalc_rq_segments(struct request *rq)
	72	{
59247eae	73	rq->nr_phys_segments = __blk_recalc_rq_segments(rq->q, rq->bio);
d6d48196 JA	74	}
	75
	76	void blk_recount_segments(struct request_queue q, struct bio bio)
	77	{
d6d48196	78	struct bio *nxt = bio->bi_next;
1e428079	79
d6d48196	80	bio->bi_next = NULL;
59247eae	81	bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio);
d6d48196	82	bio->bi_next = nxt;
d6d48196 JA	83	bio->bi_flags \|= (1 << BIO_SEG_VALID);
	84	}
	85	EXPORT_SYMBOL(blk_recount_segments);
	86
	87	static int blk_phys_contig_segment(struct request_queue q, struct bio bio,
	88	struct bio *nxt)
	89	{
e692cb66	90	if (!blk_queue_cluster(q))
d6d48196 JA	91	return 0;
d6d48196 JA	92
86771427	93	if (bio->bi_seg_back_size + nxt->bi_seg_front_size >
ae03bf63	94	queue_max_segment_size(q))
d6d48196 JA	95	return 0;
d6d48196 JA	96
e17fc0a1 DW	97	if (!bio_has_data(bio))
	98	return 1;
	99
	100	if (!BIOVEC_PHYS_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt)))
	101	return 0;
	102
d6d48196	103	/*
e17fc0a1	104	* bio and nxt are contiguous in memory; check if the queue allows
d6d48196 JA	105	* these two to be merged into one
	106	*/
	107	if (BIO_SEG_BOUNDARY(q, bio, nxt))
	108	return 1;
	109
	110	return 0;
	111	}
	112
963ab9e5 AH	113	static void
	114	__blk_segment_map_sg(struct request_queue q, struct bio_vec bvec,
	115	struct scatterlist sglist, struct bio_vec *bvprv,
	116	struct scatterlist *sg, int nsegs, int *cluster)
	117	{
	118
	119	int nbytes = bvec->bv_len;
	120
	121	if (bvprv && cluster) {
	122	if ((*sg)->length + nbytes > queue_max_segment_size(q))
	123	goto new_segment;
	124
	125	if (!BIOVEC_PHYS_MERGEABLE(*bvprv, bvec))
	126	goto new_segment;
	127	if (!BIOVEC_SEG_BOUNDARY(q, *bvprv, bvec))
	128	goto new_segment;
	129
	130	(*sg)->length += nbytes;
	131	} else {
	132	new_segment:
	133	if (!*sg)
	134	*sg = sglist;
	135	else {
	136	/*
	137	* If the driver previously mapped a shorter
	138	* list, we could see a termination bit
	139	* prematurely unless it fully inits the sg
	140	* table on each mapping. We KNOW that there
	141	* must be more entries here or the driver
	142	* would be buggy, so force clear the
	143	* termination bit to avoid doing a full
	144	* sg_init_table() in drivers for each command.
	145	*/
c8164d89	146	sg_unmark_end(*sg);
963ab9e5 AH	147	sg = sg_next(sg);
	148	}
	149
	150	sg_set_page(*sg, bvec->bv_page, nbytes, bvec->bv_offset);
	151	(*nsegs)++;
	152	}
	153	*bvprv = bvec;
	154	}
	155
d6d48196 JA	156	/*
	157	* map a request to scatterlist, return number of sg entries setup. Caller
	158	* must make sure sg can hold rq->nr_phys_segments entries
	159	*/
	160	int blk_rq_map_sg(struct request_queue q, struct request rq,
	161	struct scatterlist *sglist)
	162	{
	163	struct bio_vec bvec, bvprv;
	164	struct req_iterator iter;
	165	struct scatterlist *sg;
	166	int nsegs, cluster;
6fa3eb70 S	167	#if defined(FEATURE_STORAGE_PID_LOGGER)
	168	struct page_pid_logger *prev_logger = 0;
	169	#endif
d6d48196 JA	170
d6d48196 JA	171	nsegs = 0;
e692cb66	172	cluster = blk_queue_cluster(q);
d6d48196 JA	173
	174	/*
	175	* for each bio in rq
	176	*/
	177	bvprv = NULL;
	178	sg = NULL;
	179	rq_for_each_segment(bvec, rq, iter) {
963ab9e5 AH	180	__blk_segment_map_sg(q, bvec, sglist, &bvprv, &sg,
963ab9e5 AH	181	&nsegs, &cluster);
6fa3eb70 S	182	//#undef FEATURE_STORAGE_PID_LOGGER
	183	#if defined(FEATURE_STORAGE_PID_LOGGER)
	184	do {
	185	extern spinlock_t g_locker;
	186	extern unsigned char *page_logger;
	187
	188	extern struct struct_pid_logger g_pid_logger[PID_ID_CNT];
	189	unsigned long flags;
	190	if(page_logger) {
	191	struct page_pid_logger *tmp_logger;
	192	unsigned long page_offset;
	193	int index, mmcqd_index;
	194	pid_t current_pid=0;
	195	//#if defined(CONFIG_FLATMEM)
	196	//page_offset = (unsigned long)((bvec->bv_page) - mem_map);
	197	//#else
	198	page_offset = (unsigned long)(__page_to_pfn(bvec->bv_page))- PHYS_PFN_OFFSET;
	199	//#endif
	200	tmp_logger =((struct page_pid_logger *)page_logger) + page_offset;
	201	//tmp_locker =((struct page_pid_locker *)page_logger_lock) + page_offset;
	202	#if defined(CONFIG_FLATMEM)
	203	//printk(KERN_INFO"hank merge pid1:%u pid2:%u bv_page:%p vmemmap:%p pfn:%ld %s \n", tmp_logger->pid1, tmp_logger->pid2, bvec->bv_page, vmemmap, (unsigned long)(__page_to_pfn(bvec->bv_page)), q->backing_dev_info.name);
	204	#else
	205	//printk(KERN_INFO"hank merge pid1:%u pid2:%u bv_page:%x mem_map:%x pfn:%d %s \n", tmp_logger->pid1, tmp_logger->pid2, bvec->bv_page, mem_map, (unsigned long)(__page_to_pfn(bvec->bv_page)), q->backing_dev_info.name);
	206	#endif
	207	current_pid = current->pid;
	208
	209	//find the exactly pid record array
	210	for( mmcqd_index=0; mmcqd_index<PID_ID_CNT; mmcqd_index++) {
	211	//printk(KERN_INFO"hank merge mmcqd_index:%d qcurrent_pid:%d current_pid:%d", mmcqd_index, g_pid_logger[mmcqd_index].current_pid, current_pid);
	212	if( g_pid_logger[mmcqd_index].current_pid==0 \|\| g_pid_logger[mmcqd_index].current_pid == current_pid ) {
	213	g_pid_logger[mmcqd_index].current_pid = current_pid;
	214	break;
	215	}
	216	}
	217	//no match array
	218	if( mmcqd_index == PID_ID_CNT )
	219	break;
	220	/*
	221	if( tmp_logger->pid1 == 0XFFFF && tmp_logger->pid2 == 0XFFFF)
	222	{
	223	printk(KERN_INFO"hank merge fail offset:%d of:%d bytes:%d rw:%d", page_offset, bvec->bv_offset, nbytes, (rq->cmd_flags & REQ_WRITE));
	224	}else
	225	{
	226	printk(KERN_INFO"hank merge success offset:%d of:%d bytes:%d rw:%d", page_offset, bvec->bv_offset, nbytes, (rq->cmd_flags & REQ_WRITE));
	227	}
	228	*/
	229	if( tmp_logger->pid1 != 0xFFFF) {
	230	spin_lock_irqsave(&g_locker, flags);
	231	for( index=0; index<PID_LOGGER_COUNT; index++) {
	232	if( tmp_logger->pid1 == 0xFFFF)
	233	break;
	234	if( (g_pid_logger[mmcqd_index].pid_logger[index] == 0 \|\| g_pid_logger[mmcqd_index].pid_logger[index] == tmp_logger->pid1)) {
	235	g_pid_logger[mmcqd_index].pid_logger[index] = tmp_logger->pid1;
	236	if (rq->cmd_flags & REQ_WRITE) {
	237	g_pid_logger[mmcqd_index].pid_logger_counter[index]++;
	238	g_pid_logger[mmcqd_index].pid_logger_length[index]+=bvec->bv_len;
	239	}else {
	240	g_pid_logger[mmcqd_index].pid_logger_r_counter[index]++;
	241	g_pid_logger[mmcqd_index].pid_logger_r_length[index]+=bvec->bv_len;
	242	}
	243	if( prev_logger && prev_logger != tmp_logger)
	244	prev_logger->pid1 = 0XFFFF;
	245	//tmp_logger->pid1 = 0XFFFF;
246	break;
247	}
248
249	}
250	spin_unlock_irqrestore(&g_locker, flags);
251	}
252	if( tmp_logger->pid2 != 0xFFFF) {
253	spin_lock_irqsave(&g_locker, flags);
254	for( index=0; index<PID_LOGGER_COUNT; index++) {
255	if( tmp_logger->pid2 == 0xFFFF)
256	break;
257	if( (g_pid_logger[mmcqd_index].pid_logger[index] == 0 \|\| g_pid_logger[mmcqd_index].pid_logger[index] == tmp_logger->pid2)) {
258	g_pid_logger[mmcqd_index].pid_logger[index] = tmp_logger->pid2;
259	if (rq->cmd_flags & REQ_WRITE) {
260	g_pid_logger[mmcqd_index].pid_logger_counter[index]++;
261	g_pid_logger[mmcqd_index].pid_logger_length[index]+=bvec->bv_len;
262	}else {
263	g_pid_logger[mmcqd_index].pid_logger_r_counter[index]++;
264	g_pid_logger[mmcqd_index].pid_logger_r_length[index]+=bvec->bv_len;
265	}
266	if( prev_logger && prev_logger != tmp_logger)
267	prev_logger->pid2 = 0XFFFF;
268	//tmp_logger->pid2 = 0XFFFF;
269	break;
270	}
271
272	}
273	spin_unlock_irqrestore(&g_locker, flags);
274	}
275	prev_logger = tmp_logger;
276
277	}
278	} while (0);
279
280	#endif
d6d48196 JA	281	} /* segments in rq */
d6d48196 JA	282
f18573ab FT	283
f18573ab FT	284	if (unlikely(rq->cmd_flags & REQ_COPY_USER) &&
2e46e8b2 TH	285	(blk_rq_bytes(rq) & q->dma_pad_mask)) {
	286	unsigned int pad_len =
	287	(q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1;
f18573ab FT	288
	289	sg->length += pad_len;
	290	rq->extra_len += pad_len;
	291	}
	292
2fb98e84	293	if (q->dma_drain_size && q->dma_drain_needed(rq)) {
7b6d91da	294	if (rq->cmd_flags & REQ_WRITE)
db0a2e00 TH	295	memset(q->dma_drain_buffer, 0, q->dma_drain_size);
db0a2e00 TH	296
d6d48196 JA	297	sg->page_link &= ~0x02;
	298	sg = sg_next(sg);
	299	sg_set_page(sg, virt_to_page(q->dma_drain_buffer),
	300	q->dma_drain_size,
	301	((unsigned long)q->dma_drain_buffer) &
	302	(PAGE_SIZE - 1));
	303	nsegs++;
7a85f889	304	rq->extra_len += q->dma_drain_size;
d6d48196 JA	305	}
	306
	307	if (sg)
	308	sg_mark_end(sg);
	309
	310	return nsegs;
	311	}
d6d48196 JA	312	EXPORT_SYMBOL(blk_rq_map_sg);
d6d48196 JA	313
85b9f66a AH	314	/**
	315	* blk_bio_map_sg - map a bio to a scatterlist
	316	* @q: request_queue in question
	317	* @bio: bio being mapped
	318	* @sglist: scatterlist being mapped
	319	*
	320	* Note:
	321	* Caller must make sure sg can hold bio->bi_phys_segments entries
	322	*
	323	* Will return the number of sg entries setup
	324	*/
	325	int blk_bio_map_sg(struct request_queue q, struct bio bio,
	326	struct scatterlist *sglist)
	327	{
	328	struct bio_vec bvec, bvprv;
	329	struct scatterlist *sg;
	330	int nsegs, cluster;
	331	unsigned long i;
	332
	333	nsegs = 0;
	334	cluster = blk_queue_cluster(q);
	335
	336	bvprv = NULL;
	337	sg = NULL;
	338	bio_for_each_segment(bvec, bio, i) {
	339	__blk_segment_map_sg(q, bvec, sglist, &bvprv, &sg,
	340	&nsegs, &cluster);
	341	} /* segments in bio */
	342
	343	if (sg)
	344	sg_mark_end(sg);
	345
	346	BUG_ON(bio->bi_phys_segments && nsegs > bio->bi_phys_segments);
	347	return nsegs;
	348	}
	349	EXPORT_SYMBOL(blk_bio_map_sg);
	350
d6d48196 JA	351	static inline int ll_new_hw_segment(struct request_queue *q,
	352	struct request *req,
	353	struct bio *bio)
	354	{
d6d48196 JA	355	int nr_phys_segs = bio_phys_segments(q, bio);
d6d48196 JA	356
13f05c8d MP	357	if (req->nr_phys_segments + nr_phys_segs > queue_max_segments(q))
	358	goto no_merge;
	359
	360	if (bio_integrity(bio) && blk_integrity_merge_bio(q, req, bio))
	361	goto no_merge;
d6d48196 JA	362
	363	/*
	364	* This will form the start of a new hw segment. Bump both
	365	* counters.
	366	*/
d6d48196 JA	367	req->nr_phys_segments += nr_phys_segs;
d6d48196 JA	368	return 1;
13f05c8d MP	369
	370	no_merge:
	371	req->cmd_flags \|= REQ_NOMERGE;
	372	if (req == q->last_merge)
	373	q->last_merge = NULL;
	374	return 0;
d6d48196 JA	375	}
	376
	377	int ll_back_merge_fn(struct request_queue q, struct request req,
	378	struct bio *bio)
	379	{
f31dc1cd MP	380	if (blk_rq_sectors(req) + bio_sectors(bio) >
f31dc1cd MP	381	blk_rq_get_max_sectors(req)) {
d6d48196 JA	382	req->cmd_flags \|= REQ_NOMERGE;
	383	if (req == q->last_merge)
	384	q->last_merge = NULL;
	385	return 0;
	386	}
2cdf79ca	387	if (!bio_flagged(req->biotail, BIO_SEG_VALID))
d6d48196	388	blk_recount_segments(q, req->biotail);
2cdf79ca	389	if (!bio_flagged(bio, BIO_SEG_VALID))
d6d48196	390	blk_recount_segments(q, bio);
d6d48196 JA	391
	392	return ll_new_hw_segment(q, req, bio);
	393	}
	394
6728cb0e	395	int ll_front_merge_fn(struct request_queue q, struct request req,
d6d48196 JA	396	struct bio *bio)
d6d48196 JA	397	{
f31dc1cd MP	398	if (blk_rq_sectors(req) + bio_sectors(bio) >
f31dc1cd MP	399	blk_rq_get_max_sectors(req)) {
d6d48196 JA	400	req->cmd_flags \|= REQ_NOMERGE;
	401	if (req == q->last_merge)
	402	q->last_merge = NULL;
	403	return 0;
	404	}
2cdf79ca	405	if (!bio_flagged(bio, BIO_SEG_VALID))
d6d48196	406	blk_recount_segments(q, bio);
2cdf79ca	407	if (!bio_flagged(req->bio, BIO_SEG_VALID))
d6d48196	408	blk_recount_segments(q, req->bio);
d6d48196 JA	409
	410	return ll_new_hw_segment(q, req, bio);
	411	}
	412
	413	static int ll_merge_requests_fn(struct request_queue q, struct request req,
	414	struct request *next)
	415	{
	416	int total_phys_segments;
86771427 FT	417	unsigned int seg_size =
86771427 FT	418	req->biotail->bi_seg_back_size + next->bio->bi_seg_front_size;
d6d48196 JA	419
	420	/*
	421	* First check if the either of the requests are re-queued
	422	* requests. Can't merge them if they are.
	423	*/
	424	if (req->special \|\| next->special)
	425	return 0;
	426
	427	/*
	428	* Will it become too large?
	429	*/
f31dc1cd MP	430	if ((blk_rq_sectors(req) + blk_rq_sectors(next)) >
f31dc1cd MP	431	blk_rq_get_max_sectors(req))
d6d48196 JA	432	return 0;
	433
	434	total_phys_segments = req->nr_phys_segments + next->nr_phys_segments;
86771427 FT	435	if (blk_phys_contig_segment(q, req->biotail, next->bio)) {
	436	if (req->nr_phys_segments == 1)
	437	req->bio->bi_seg_front_size = seg_size;
	438	if (next->nr_phys_segments == 1)
	439	next->biotail->bi_seg_back_size = seg_size;
d6d48196	440	total_phys_segments--;
86771427	441	}
d6d48196	442
8a78362c	443	if (total_phys_segments > queue_max_segments(q))
d6d48196 JA	444	return 0;
d6d48196 JA	445
13f05c8d MP	446	if (blk_integrity_rq(req) && blk_integrity_merge_rq(q, req, next))
	447	return 0;
	448
d6d48196 JA	449	/* Merge is OK... */
d6d48196 JA	450	req->nr_phys_segments = total_phys_segments;
d6d48196 JA	451	return 1;
	452	}
	453
80a761fd TH	454	/**
	455	* blk_rq_set_mixed_merge - mark a request as mixed merge
	456	* @rq: request to mark as mixed merge
	457	*
	458	* Description:
	459	* @rq is about to be mixed merged. Make sure the attributes
	460	* which can be mixed are set in each bio and mark @rq as mixed
	461	* merged.
	462	*/
	463	void blk_rq_set_mixed_merge(struct request *rq)
	464	{
	465	unsigned int ff = rq->cmd_flags & REQ_FAILFAST_MASK;
	466	struct bio *bio;
	467
	468	if (rq->cmd_flags & REQ_MIXED_MERGE)
	469	return;
	470
	471	/*
	472	* @rq will no longer represent mixable attributes for all the
	473	* contained bios. It will just track those of the first one.
	474	* Distributes the attributs to each bio.
	475	*/
	476	for (bio = rq->bio; bio; bio = bio->bi_next) {
	477	WARN_ON_ONCE((bio->bi_rw & REQ_FAILFAST_MASK) &&
	478	(bio->bi_rw & REQ_FAILFAST_MASK) != ff);
	479	bio->bi_rw \|= ff;
	480	}
	481	rq->cmd_flags \|= REQ_MIXED_MERGE;
	482	}
	483
26308eab JM	484	static void blk_account_io_merge(struct request *req)
	485	{
	486	if (blk_do_io_stat(req)) {
	487	struct hd_struct *part;
	488	int cpu;
	489
	490	cpu = part_stat_lock();
09e099d4	491	part = req->part;
26308eab JM	492
26308eab JM	493	part_round_stats(cpu, part);
316d315b	494	part_dec_in_flight(part, rq_data_dir(req));
26308eab	495
6c23a968	496	hd_struct_put(part);
26308eab JM	497	part_stat_unlock();
	498	}
	499	}
	500
d6d48196 JA	501	/*
	502	* Has to be called with the request spinlock acquired
	503	*/
	504	static int attempt_merge(struct request_queue q, struct request req,
	505	struct request *next)
	506	{
	507	if (!rq_mergeable(req) \|\| !rq_mergeable(next))
	508	return 0;
	509
f31dc1cd MP	510	if (!blk_check_merge_flags(req->cmd_flags, next->cmd_flags))
	511	return 0;
	512
d6d48196 JA	513	/*
	514	* not contiguous
	515	*/
83096ebf	516	if (blk_rq_pos(req) + blk_rq_sectors(req) != blk_rq_pos(next))
d6d48196 JA	517	return 0;
	518
	519	if (rq_data_dir(req) != rq_data_dir(next)
	520	\|\| req->rq_disk != next->rq_disk
	521	\|\| next->special)
	522	return 0;
	523
4363ac7c MP	524	if (req->cmd_flags & REQ_WRITE_SAME &&
	525	!blk_write_same_mergeable(req->bio, next->bio))
	526	return 0;
	527
d6d48196 JA	528	/*
	529	* If we are allowed to merge, then append bio list
	530	* from next to rq and release next. merge_requests_fn
	531	* will have updated segment counts, update sector
	532	* counts here.
	533	*/
	534	if (!ll_merge_requests_fn(q, req, next))
	535	return 0;
	536
80a761fd TH	537	/*
	538	* If failfast settings disagree or any of the two is already
	539	* a mixed merge, mark both as mixed before proceeding. This
	540	* makes sure that all involved bios have mixable attributes
	541	* set properly.
	542	*/
	543	if ((req->cmd_flags \| next->cmd_flags) & REQ_MIXED_MERGE \|\|
	544	(req->cmd_flags & REQ_FAILFAST_MASK) !=
	545	(next->cmd_flags & REQ_FAILFAST_MASK)) {
	546	blk_rq_set_mixed_merge(req);
	547	blk_rq_set_mixed_merge(next);
	548	}
	549
d6d48196 JA	550	/*
	551	* At this point we have either done a back merge
	552	* or front merge. We need the smaller start_time of
	553	* the merged requests to be the current request
	554	* for accounting purposes.
	555	*/
	556	if (time_after(req->start_time, next->start_time))
	557	req->start_time = next->start_time;
	558
	559	req->biotail->bi_next = next->bio;
	560	req->biotail = next->biotail;
	561
a2dec7b3	562	req->__data_len += blk_rq_bytes(next);
d6d48196 JA	563
	564	elv_merge_requests(q, req, next);
	565
42dad764 JM	566	/*
	567	* 'next' is going away, so update stats accordingly
	568	*/
	569	blk_account_io_merge(next);
d6d48196 JA	570
d6d48196 JA	571	req->ioprio = ioprio_best(req->ioprio, next->ioprio);
ab780f1e JA	572	if (blk_rq_cpu_valid(next))
ab780f1e JA	573	req->cpu = next->cpu;
d6d48196	574
1cd96c24 BH	575	/* owner-ship of bio passed from next to req */
1cd96c24 BH	576	next->bio = NULL;
d6d48196 JA	577	__blk_put_request(q, next);
	578	return 1;
	579	}
	580
	581	int attempt_back_merge(struct request_queue q, struct request rq)
	582	{
	583	struct request *next = elv_latter_request(q, rq);
	584
	585	if (next)
	586	return attempt_merge(q, rq, next);
	587
	588	return 0;
	589	}
	590
	591	int attempt_front_merge(struct request_queue q, struct request rq)
	592	{
	593	struct request *prev = elv_former_request(q, rq);
	594
	595	if (prev)
	596	return attempt_merge(q, prev, rq);
	597
	598	return 0;
	599	}
5e84ea3a JA	600
	601	int blk_attempt_req_merge(struct request_queue q, struct request rq,
	602	struct request *next)
	603	{
	604	return attempt_merge(q, rq, next);
	605	}
050c8ea8 TH	606
	607	bool blk_rq_merge_ok(struct request rq, struct bio bio)
	608	{
e2a60da7	609	if (!rq_mergeable(rq) \|\| !bio_mergeable(bio))
050c8ea8 TH	610	return false;
050c8ea8 TH	611
f31dc1cd MP	612	if (!blk_check_merge_flags(rq->cmd_flags, bio->bi_rw))
	613	return false;
	614
050c8ea8 TH	615	/* different data direction or already started, don't merge */
	616	if (bio_data_dir(bio) != rq_data_dir(rq))
	617	return false;
	618
	619	/* must be same device and not a special request */
	620	if (rq->rq_disk != bio->bi_bdev->bd_disk \|\| rq->special)
	621	return false;
	622
	623	/* only merge integrity protected bio into ditto rq */
	624	if (bio_integrity(bio) != blk_integrity_rq(rq))
	625	return false;
	626
4363ac7c MP	627	/* must be using the same buffer */
	628	if (rq->cmd_flags & REQ_WRITE_SAME &&
	629	!blk_write_same_mergeable(rq->bio, bio))
	630	return false;
	631
050c8ea8 TH	632	return true;
	633	}
	634
	635	int blk_try_merge(struct request rq, struct bio bio)
	636	{
	637	if (blk_rq_pos(rq) + blk_rq_sectors(rq) == bio->bi_sector)
	638	return ELEVATOR_BACK_MERGE;
	639	else if (blk_rq_pos(rq) - bio_sectors(bio) == bio->bi_sector)
	640	return ELEVATOR_FRONT_MERGE;
	641	return ELEVATOR_NO_MERGE;
	642	}