* Copyright (C) 1994, Karl Keyte: Added support for disk statistics
* Elevator latency, (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE
* Queue request tables / lock, selectable elevator, Jens Axboe <axboe@suse.de>
- * kernel-doc documentation started by NeilBrown <neilb@cse.unsw.edu.au> - July2000
+ * kernel-doc documentation started by NeilBrown <neilb@cse.unsw.edu.au>
+ * - July2000
* bio rewrite, highmem i/o, etc, Jens Axboe <axboe@suse.de> - may 2001
*/
#include <linux/cpu.h>
#include <linux/blktrace_api.h>
#include <linux/fault-inject.h>
-#include <linux/scatterlist.h>
#include "blk.h"
/*
* For the allocated request tables
*/
-struct kmem_cache *request_cachep;
+static struct kmem_cache *request_cachep;
/*
* For queue allocation
*/
-struct kmem_cache *blk_requestq_cachep = NULL;
+struct kmem_cache *blk_requestq_cachep;
/*
* Controlling structure to kblockd
static void drive_stat_acct(struct request *rq, int new_io)
{
+ struct hd_struct *part;
int rw = rq_data_dir(rq);
if (!blk_fs_request(rq) || !rq->rq_disk)
return;
- if (!new_io) {
- __disk_stat_inc(rq->rq_disk, merges[rw]);
- } else {
+ part = get_part(rq->rq_disk, rq->sector);
+ if (!new_io)
+ __all_stat_inc(rq->rq_disk, part, merges[rw], rq->sector);
+ else {
disk_round_stats(rq->rq_disk);
rq->rq_disk->in_flight++;
+ if (part) {
+ part_round_stats(part);
+ part->in_flight++;
+ }
}
}
}
EXPORT_SYMBOL(blk_get_backing_dev_info);
-void rq_init(struct request_queue *q, struct request *rq)
+void blk_rq_init(struct request_queue *q, struct request *rq)
{
+ memset(rq, 0, sizeof(*rq));
+
INIT_LIST_HEAD(&rq->queuelist);
INIT_LIST_HEAD(&rq->donelist);
-
- rq->errors = 0;
- rq->bio = rq->biotail = NULL;
+ rq->q = q;
+ rq->sector = rq->hard_sector = (sector_t) -1;
INIT_HLIST_NODE(&rq->hash);
RB_CLEAR_NODE(&rq->rb_node);
- rq->ioprio = 0;
- rq->buffer = NULL;
+ rq->cmd = rq->__cmd;
+ rq->tag = -1;
rq->ref_count = 1;
- rq->q = q;
- rq->special = NULL;
- rq->data_len = 0;
- rq->data = NULL;
- rq->nr_phys_segments = 0;
- rq->sense = NULL;
- rq->end_io = NULL;
- rq->end_io_data = NULL;
- rq->completion_data = NULL;
- rq->next_rq = NULL;
}
+EXPORT_SYMBOL(blk_rq_init);
static void req_bio_endio(struct request *rq, struct bio *bio,
unsigned int nbytes, int error)
error = -EIO;
if (unlikely(nbytes > bio->bi_size)) {
- printk("%s: want %u bytes done, only %u left\n",
- __FUNCTION__, nbytes, bio->bi_size);
+ printk(KERN_ERR "%s: want %u bytes done, %u left\n",
+ __func__, nbytes, bio->bi_size);
nbytes = bio->bi_size;
}
{
int bit;
- printk("%s: dev %s: type=%x, flags=%x\n", msg,
+ printk(KERN_INFO "%s: dev %s: type=%x, flags=%x\n", msg,
rq->rq_disk ? rq->rq_disk->disk_name : "?", rq->cmd_type,
rq->cmd_flags);
- printk("\nsector %llu, nr/cnr %lu/%u\n", (unsigned long long)rq->sector,
- rq->nr_sectors,
- rq->current_nr_sectors);
- printk("bio %p, biotail %p, buffer %p, data %p, len %u\n", rq->bio, rq->biotail, rq->buffer, rq->data, rq->data_len);
+ printk(KERN_INFO " sector %llu, nr/cnr %lu/%u\n",
+ (unsigned long long)rq->sector,
+ rq->nr_sectors,
+ rq->current_nr_sectors);
+ printk(KERN_INFO " bio %p, biotail %p, buffer %p, data %p, len %u\n",
+ rq->bio, rq->biotail,
+ rq->buffer, rq->data,
+ rq->data_len);
if (blk_pc_request(rq)) {
- printk("cdb: ");
- for (bit = 0; bit < sizeof(rq->cmd); bit++)
+ printk(KERN_INFO " cdb: ");
+ for (bit = 0; bit < BLK_MAX_CDB; bit++)
printk("%02x ", rq->cmd[bit]);
printk("\n");
}
}
-
EXPORT_SYMBOL(blk_dump_rq_flags);
-static void blk_recalc_rq_segments(struct request *rq)
-{
- int nr_phys_segs;
- int nr_hw_segs;
- unsigned int phys_size;
- unsigned int hw_size;
- struct bio_vec *bv, *bvprv = NULL;
- int seg_size;
- int hw_seg_size;
- int cluster;
- struct req_iterator iter;
- int high, highprv = 1;
- struct request_queue *q = rq->q;
-
- if (!rq->bio)
- return;
-
- cluster = q->queue_flags & (1 << QUEUE_FLAG_CLUSTER);
- hw_seg_size = seg_size = 0;
- phys_size = hw_size = nr_phys_segs = nr_hw_segs = 0;
- rq_for_each_segment(bv, rq, iter) {
- /*
- * 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) > q->bounce_pfn;
- if (high || highprv)
- goto new_hw_segment;
- if (cluster) {
- if (seg_size + bv->bv_len > q->max_segment_size)
- goto new_segment;
- if (!BIOVEC_PHYS_MERGEABLE(bvprv, bv))
- goto new_segment;
- if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bv))
- goto new_segment;
- if (BIOVEC_VIRT_OVERSIZE(hw_seg_size + bv->bv_len))
- goto new_hw_segment;
-
- seg_size += bv->bv_len;
- hw_seg_size += bv->bv_len;
- bvprv = bv;
- continue;
- }
-new_segment:
- if (BIOVEC_VIRT_MERGEABLE(bvprv, bv) &&
- !BIOVEC_VIRT_OVERSIZE(hw_seg_size + bv->bv_len))
- hw_seg_size += bv->bv_len;
- else {
-new_hw_segment:
- if (nr_hw_segs == 1 &&
- hw_seg_size > rq->bio->bi_hw_front_size)
- rq->bio->bi_hw_front_size = hw_seg_size;
- hw_seg_size = BIOVEC_VIRT_START_SIZE(bv) + bv->bv_len;
- nr_hw_segs++;
- }
-
- nr_phys_segs++;
- bvprv = bv;
- seg_size = bv->bv_len;
- highprv = high;
- }
-
- if (nr_hw_segs == 1 &&
- hw_seg_size > rq->bio->bi_hw_front_size)
- rq->bio->bi_hw_front_size = hw_seg_size;
- if (hw_seg_size > rq->biotail->bi_hw_back_size)
- rq->biotail->bi_hw_back_size = hw_seg_size;
- rq->nr_phys_segments = nr_phys_segs;
- rq->nr_hw_segments = nr_hw_segs;
-}
-
-void blk_recount_segments(struct request_queue *q, struct bio *bio)
-{
- struct request rq;
- struct bio *nxt = bio->bi_next;
- rq.q = q;
- rq.bio = rq.biotail = bio;
- bio->bi_next = NULL;
- blk_recalc_rq_segments(&rq);
- bio->bi_next = nxt;
- bio->bi_phys_segments = rq.nr_phys_segments;
- bio->bi_hw_segments = rq.nr_hw_segments;
- 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 (!(q->queue_flags & (1 << QUEUE_FLAG_CLUSTER)))
- return 0;
-
- if (!BIOVEC_PHYS_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt)))
- return 0;
- if (bio->bi_size + nxt->bi_size > q->max_segment_size)
- return 0;
-
- /*
- * bio and nxt are contigous 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 int blk_hw_contig_segment(struct request_queue *q, struct bio *bio,
- struct bio *nxt)
-{
- if (unlikely(!bio_flagged(bio, BIO_SEG_VALID)))
- blk_recount_segments(q, bio);
- if (unlikely(!bio_flagged(nxt, BIO_SEG_VALID)))
- blk_recount_segments(q, nxt);
- if (!BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt)) ||
- BIOVEC_VIRT_OVERSIZE(bio->bi_hw_back_size + nxt->bi_hw_front_size))
- return 0;
- if (bio->bi_hw_back_size + nxt->bi_hw_front_size > q->max_segment_size)
- return 0;
-
- return 1;
-}
-
-/*
- * 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;
-
- nsegs = 0;
- cluster = q->queue_flags & (1 << QUEUE_FLAG_CLUSTER);
-
- /*
- * for each bio in rq
- */
- bvprv = NULL;
- sg = NULL;
- rq_for_each_segment(bvec, rq, iter) {
- int nbytes = bvec->bv_len;
-
- if (bvprv && cluster) {
- if (sg->length + nbytes > q->max_segment_size)
- 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->page_link &= ~0x02;
- sg = sg_next(sg);
- }
-
- sg_set_page(sg, bvec->bv_page, nbytes, bvec->bv_offset);
- nsegs++;
- }
- bvprv = bvec;
- } /* segments in rq */
-
- if (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++;
- }
-
- if (sg)
- sg_mark_end(sg);
-
- return nsegs;
-}
-
-EXPORT_SYMBOL(blk_rq_map_sg);
-
-static inline int ll_new_mergeable(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 > q->max_phys_segments) {
- req->cmd_flags |= REQ_NOMERGE;
- if (req == q->last_merge)
- q->last_merge = NULL;
- return 0;
- }
-
- /*
- * A hw segment is just getting larger, bump just the phys
- * counter.
- */
- req->nr_phys_segments += nr_phys_segs;
- return 1;
-}
-
-static inline int ll_new_hw_segment(struct request_queue *q,
- struct request *req,
- struct bio *bio)
-{
- int nr_hw_segs = bio_hw_segments(q, bio);
- int nr_phys_segs = bio_phys_segments(q, bio);
-
- if (req->nr_hw_segments + nr_hw_segs > q->max_hw_segments
- || req->nr_phys_segments + nr_phys_segs > q->max_phys_segments) {
- req->cmd_flags |= REQ_NOMERGE;
- if (req == q->last_merge)
- q->last_merge = NULL;
- return 0;
- }
-
- /*
- * This will form the start of a new hw segment. Bump both
- * counters.
- */
- req->nr_hw_segments += nr_hw_segs;
- req->nr_phys_segments += nr_phys_segs;
- return 1;
-}
-
-int ll_back_merge_fn(struct request_queue *q, struct request *req,
- struct bio *bio)
-{
- unsigned short max_sectors;
- int len;
-
- if (unlikely(blk_pc_request(req)))
- max_sectors = q->max_hw_sectors;
- else
- max_sectors = q->max_sectors;
-
- if (req->nr_sectors + bio_sectors(bio) > max_sectors) {
- req->cmd_flags |= REQ_NOMERGE;
- if (req == q->last_merge)
- q->last_merge = NULL;
- return 0;
- }
- if (unlikely(!bio_flagged(req->biotail, BIO_SEG_VALID)))
- blk_recount_segments(q, req->biotail);
- if (unlikely(!bio_flagged(bio, BIO_SEG_VALID)))
- blk_recount_segments(q, bio);
- len = req->biotail->bi_hw_back_size + bio->bi_hw_front_size;
- if (BIOVEC_VIRT_MERGEABLE(__BVEC_END(req->biotail), __BVEC_START(bio)) &&
- !BIOVEC_VIRT_OVERSIZE(len)) {
- int mergeable = ll_new_mergeable(q, req, bio);
-
- if (mergeable) {
- if (req->nr_hw_segments == 1)
- req->bio->bi_hw_front_size = len;
- if (bio->bi_hw_segments == 1)
- bio->bi_hw_back_size = len;
- }
- return mergeable;
- }
-
- return ll_new_hw_segment(q, req, bio);
-}
-
-static int ll_front_merge_fn(struct request_queue *q, struct request *req,
- struct bio *bio)
-{
- unsigned short max_sectors;
- int len;
-
- if (unlikely(blk_pc_request(req)))
- max_sectors = q->max_hw_sectors;
- else
- max_sectors = q->max_sectors;
-
-
- if (req->nr_sectors + bio_sectors(bio) > max_sectors) {
- req->cmd_flags |= REQ_NOMERGE;
- if (req == q->last_merge)
- q->last_merge = NULL;
- return 0;
- }
- len = bio->bi_hw_back_size + req->bio->bi_hw_front_size;
- if (unlikely(!bio_flagged(bio, BIO_SEG_VALID)))
- blk_recount_segments(q, bio);
- if (unlikely(!bio_flagged(req->bio, BIO_SEG_VALID)))
- blk_recount_segments(q, req->bio);
- if (BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(req->bio)) &&
- !BIOVEC_VIRT_OVERSIZE(len)) {
- int mergeable = ll_new_mergeable(q, req, bio);
-
- if (mergeable) {
- if (bio->bi_hw_segments == 1)
- bio->bi_hw_front_size = len;
- if (req->nr_hw_segments == 1)
- req->biotail->bi_hw_back_size = len;
- }
- return mergeable;
- }
-
- 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;
- int total_hw_segments;
-
- /*
- * 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 ((req->nr_sectors + next->nr_sectors) > q->max_sectors)
- return 0;
-
- total_phys_segments = req->nr_phys_segments + next->nr_phys_segments;
- if (blk_phys_contig_segment(q, req->biotail, next->bio))
- total_phys_segments--;
-
- if (total_phys_segments > q->max_phys_segments)
- return 0;
-
- total_hw_segments = req->nr_hw_segments + next->nr_hw_segments;
- if (blk_hw_contig_segment(q, req->biotail, next->bio)) {
- int len = req->biotail->bi_hw_back_size + next->bio->bi_hw_front_size;
- /*
- * propagate the combined length to the end of the requests
- */
- if (req->nr_hw_segments == 1)
- req->bio->bi_hw_front_size = len;
- if (next->nr_hw_segments == 1)
- next->biotail->bi_hw_back_size = len;
- total_hw_segments--;
- }
-
- if (total_hw_segments > q->max_hw_segments)
- return 0;
-
- /* Merge is OK... */
- req->nr_phys_segments = total_phys_segments;
- req->nr_hw_segments = total_hw_segments;
- return 1;
-}
-
/*
* "plug" the device if there are no outstanding requests: this will
* force the transfer to start only after we have put all the requests
if (blk_queue_stopped(q))
return;
- if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) {
+ if (!test_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) {
+ __set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags);
mod_timer(&q->unplug_timer, jiffies + q->unplug_delay);
blk_add_trace_generic(q, NULL, 0, BLK_TA_PLUG);
}
}
-
EXPORT_SYMBOL(blk_plug_device);
/*
{
WARN_ON(!irqs_disabled());
- if (!test_and_clear_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags))
+ if (!test_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags))
return 0;
+ queue_flag_clear(QUEUE_FLAG_PLUGGED, q);
del_timer(&q->unplug_timer);
return 1;
}
-
EXPORT_SYMBOL(blk_remove_plug);
/*
**/
void generic_unplug_device(struct request_queue *q)
{
- spin_lock_irq(q->queue_lock);
- __generic_unplug_device(q);
- spin_unlock_irq(q->queue_lock);
+ if (blk_queue_plugged(q)) {
+ spin_lock_irq(q->queue_lock);
+ __generic_unplug_device(q);
+ spin_unlock_irq(q->queue_lock);
+ }
}
EXPORT_SYMBOL(generic_unplug_device);
{
WARN_ON(!irqs_disabled());
- clear_bit(QUEUE_FLAG_STOPPED, &q->queue_flags);
+ queue_flag_clear(QUEUE_FLAG_STOPPED, q);
/*
* one level of recursion is ok and is much faster than kicking
* the unplug handling
*/
- if (!test_and_set_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) {
+ if (!test_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) {
+ queue_flag_set(QUEUE_FLAG_REENTER, q);
q->request_fn(q);
- clear_bit(QUEUE_FLAG_REENTER, &q->queue_flags);
+ queue_flag_clear(QUEUE_FLAG_REENTER, q);
} else {
blk_plug_device(q);
kblockd_schedule_work(&q->unplug_work);
}
}
-
EXPORT_SYMBOL(blk_start_queue);
/**
void blk_stop_queue(struct request_queue *q)
{
blk_remove_plug(q);
- set_bit(QUEUE_FLAG_STOPPED, &q->queue_flags);
+ queue_flag_set(QUEUE_FLAG_STOPPED, q);
}
EXPORT_SYMBOL(blk_stop_queue);
* blk_run_queue - run a single device queue
* @q: The queue to run
*/
-void blk_run_queue(struct request_queue *q)
+void __blk_run_queue(struct request_queue *q)
{
- unsigned long flags;
-
- spin_lock_irqsave(q->queue_lock, flags);
blk_remove_plug(q);
/*
* handling reinvoke the handler shortly if we already got there.
*/
if (!elv_queue_empty(q)) {
- if (!test_and_set_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) {
+ if (!test_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) {
+ queue_flag_set(QUEUE_FLAG_REENTER, q);
q->request_fn(q);
- clear_bit(QUEUE_FLAG_REENTER, &q->queue_flags);
+ queue_flag_clear(QUEUE_FLAG_REENTER, q);
} else {
blk_plug_device(q);
kblockd_schedule_work(&q->unplug_work);
}
}
+}
+EXPORT_SYMBOL(__blk_run_queue);
+/**
+ * blk_run_queue - run a single device queue
+ * @q: The queue to run
+ */
+void blk_run_queue(struct request_queue *q)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ __blk_run_queue(q);
spin_unlock_irqrestore(q->queue_lock, flags);
}
EXPORT_SYMBOL(blk_run_queue);
{
kobject_put(&q->kobj);
}
-EXPORT_SYMBOL(blk_put_queue);
-void blk_cleanup_queue(struct request_queue * q)
+void blk_cleanup_queue(struct request_queue *q)
{
mutex_lock(&q->sysfs_lock);
- set_bit(QUEUE_FLAG_DEAD, &q->queue_flags);
+ queue_flag_set_unlocked(QUEUE_FLAG_DEAD, q);
mutex_unlock(&q->sysfs_lock);
if (q->elevator)
blk_put_queue(q);
}
-
EXPORT_SYMBOL(blk_cleanup_queue);
static int blk_init_free_list(struct request_queue *q)
kobject_init(&q->kobj, &blk_queue_ktype);
mutex_init(&q->sysfs_lock);
+ spin_lock_init(&q->__queue_lock);
return q;
}
* if caller didn't supply a lock, they get per-queue locking with
* our embedded lock
*/
- if (!lock) {
- spin_lock_init(&q->__queue_lock);
+ if (!lock)
lock = &q->__queue_lock;
- }
q->request_fn = rfn;
q->prep_rq_fn = NULL;
return 1;
}
-EXPORT_SYMBOL(blk_get_queue);
-
static inline void blk_free_request(struct request_queue *q, struct request *rq)
{
if (rq->cmd_flags & REQ_ELVPRIV)
if (!rq)
return NULL;
+ blk_rq_init(q, rq);
+
/*
* first three bits are identical in rq->cmd_flags and bio->bi_rw,
* see bio.h and blkdev.h
*/
if (ioc_batching(q, ioc))
ioc->nr_batch_requests--;
-
- rq_init(q, rq);
blk_add_trace_generic(q, bio, rw, BLK_TA_GETRQ);
out:
rq = get_request(q, rw_flags, bio, GFP_NOIO);
while (!rq) {
DEFINE_WAIT(wait);
+ struct io_context *ioc;
struct request_list *rl = &q->rq;
prepare_to_wait_exclusive(&rl->wait[rw], &wait,
TASK_UNINTERRUPTIBLE);
- rq = get_request(q, rw_flags, bio, GFP_NOIO);
-
- if (!rq) {
- struct io_context *ioc;
+ blk_add_trace_generic(q, bio, rw, BLK_TA_SLEEPRQ);
- blk_add_trace_generic(q, bio, rw, BLK_TA_SLEEPRQ);
-
- __generic_unplug_device(q);
- spin_unlock_irq(q->queue_lock);
- io_schedule();
+ __generic_unplug_device(q);
+ spin_unlock_irq(q->queue_lock);
+ io_schedule();
- /*
- * After sleeping, we become a "batching" process and
- * will be able to allocate at least one request, and
- * up to a big batch of them for a small period time.
- * See ioc_batching, ioc_set_batching
- */
- ioc = current_io_context(GFP_NOIO, q->node);
- ioc_set_batching(q, ioc);
+ /*
+ * After sleeping, we become a "batching" process and
+ * will be able to allocate at least one request, and
+ * up to a big batch of them for a small period time.
+ * See ioc_batching, ioc_set_batching
+ */
+ ioc = current_io_context(GFP_NOIO, q->node);
+ ioc_set_batching(q, ioc);
- spin_lock_irq(q->queue_lock);
- }
+ spin_lock_irq(q->queue_lock);
finish_wait(&rl->wait[rw], &wait);
- }
+
+ rq = get_request(q, rw_flags, bio, GFP_NOIO);
+ };
return rq;
}
elv_requeue_request(q, rq);
}
-
EXPORT_SYMBOL(blk_requeue_request);
/**
blk_start_queueing(q);
spin_unlock_irqrestore(q->queue_lock, flags);
}
-
EXPORT_SYMBOL(blk_insert_request);
/*
* queue lock is held and interrupts disabled, as we muck with the
* request queue list.
*/
-static inline void add_request(struct request_queue * q, struct request * req)
+static inline void add_request(struct request_queue *q, struct request *req)
{
drive_stat_acct(req, 1);
*/
__elv_add_request(q, req, ELEVATOR_INSERT_SORT, 0);
}
-
+
/*
* disk_round_stats() - Round off the performance stats on a struct
* disk_stats.
}
disk->stamp = now;
}
-
EXPORT_SYMBOL_GPL(disk_round_stats);
+void part_round_stats(struct hd_struct *part)
+{
+ unsigned long now = jiffies;
+
+ if (now == part->stamp)
+ return;
+
+ if (part->in_flight) {
+ __part_stat_add(part, time_in_queue,
+ part->in_flight * (now - part->stamp));
+ __part_stat_add(part, io_ticks, (now - part->stamp));
+ }
+ part->stamp = now;
+}
+
/*
* queue lock must be held
*/
freed_request(q, rw, priv);
}
}
-
EXPORT_SYMBOL_GPL(__blk_put_request);
void blk_put_request(struct request *req)
spin_unlock_irqrestore(q->queue_lock, flags);
}
}
-
EXPORT_SYMBOL(blk_put_request);
-/*
- * 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;
-
- /*
- * not contiguous
- */
- if (req->sector + req->nr_sectors != next->sector)
- return 0;
-
- if (rq_data_dir(req) != rq_data_dir(next)
- || req->rq_disk != next->rq_disk
- || next->special)
- 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;
-
- /*
- * 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->nr_sectors = req->hard_nr_sectors += next->hard_nr_sectors;
-
- elv_merge_requests(q, req, next);
-
- if (req->rq_disk) {
- disk_round_stats(req->rq_disk);
- req->rq_disk->in_flight--;
- }
-
- req->ioprio = ioprio_best(req->ioprio, next->ioprio);
-
- __blk_put_request(q, next);
- return 1;
-}
-
-static inline 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;
-}
-
-static inline 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;
-}
-
void init_request_from_bio(struct request *req, struct bio *bio)
{
req->cmd_type = REQ_TYPE_FS;
el_ret = elv_merge(q, &req, bio);
switch (el_ret) {
- case ELEVATOR_BACK_MERGE:
- BUG_ON(!rq_mergeable(req));
+ case ELEVATOR_BACK_MERGE:
+ BUG_ON(!rq_mergeable(req));
- if (!ll_back_merge_fn(q, req, bio))
- break;
+ if (!ll_back_merge_fn(q, req, bio))
+ break;
- blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE);
+ blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE);
- req->biotail->bi_next = bio;
- req->biotail = bio;
- req->nr_sectors = req->hard_nr_sectors += nr_sectors;
- req->ioprio = ioprio_best(req->ioprio, prio);
- drive_stat_acct(req, 0);
- if (!attempt_back_merge(q, req))
- elv_merged_request(q, req, el_ret);
- goto out;
+ req->biotail->bi_next = bio;
+ req->biotail = bio;
+ req->nr_sectors = req->hard_nr_sectors += nr_sectors;
+ req->ioprio = ioprio_best(req->ioprio, prio);
+ drive_stat_acct(req, 0);
+ if (!attempt_back_merge(q, req))
+ elv_merged_request(q, req, el_ret);
+ goto out;
- case ELEVATOR_FRONT_MERGE:
- BUG_ON(!rq_mergeable(req));
+ case ELEVATOR_FRONT_MERGE:
+ BUG_ON(!rq_mergeable(req));
- if (!ll_front_merge_fn(q, req, bio))
- break;
+ if (!ll_front_merge_fn(q, req, bio))
+ break;
- blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE);
+ blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE);
- bio->bi_next = req->bio;
- req->bio = bio;
+ bio->bi_next = req->bio;
+ req->bio = bio;
- /*
- * may not be valid. if the low level driver said
- * it didn't need a bounce buffer then it better
- * not touch req->buffer either...
- */
- req->buffer = bio_data(bio);
- req->current_nr_sectors = bio_cur_sectors(bio);
- req->hard_cur_sectors = req->current_nr_sectors;
- req->sector = req->hard_sector = bio->bi_sector;
- req->nr_sectors = req->hard_nr_sectors += nr_sectors;
- req->ioprio = ioprio_best(req->ioprio, prio);
- drive_stat_acct(req, 0);
- if (!attempt_front_merge(q, req))
- elv_merged_request(q, req, el_ret);
- goto out;
-
- /* ELV_NO_MERGE: elevator says don't/can't merge. */
- default:
- ;
+ /*
+ * may not be valid. if the low level driver said
+ * it didn't need a bounce buffer then it better
+ * not touch req->buffer either...
+ */
+ req->buffer = bio_data(bio);
+ req->current_nr_sectors = bio_cur_sectors(bio);
+ req->hard_cur_sectors = req->current_nr_sectors;
+ req->sector = req->hard_sector = bio->bi_sector;
+ req->nr_sectors = req->hard_nr_sectors += nr_sectors;
+ req->ioprio = ioprio_best(req->ioprio, prio);
+ drive_stat_acct(req, 0);
+ if (!attempt_front_merge(q, req))
+ elv_merged_request(q, req, el_ret);
+ goto out;
+
+ /* ELV_NO_MERGE: elevator says don't/can't merge. */
+ default:
+ ;
}
get_rq:
if (bio_sectors(bio) && bdev != bdev->bd_contains) {
struct hd_struct *p = bdev->bd_part;
- const int rw = bio_data_dir(bio);
-
- p->sectors[rw] += bio_sectors(bio);
- p->ios[rw]++;
bio->bi_sector += p->start_sect;
bio->bi_bdev = bdev->bd_contains;
}
if (unlikely(nr_sectors > q->max_hw_sectors)) {
- printk("bio too big device %s (%u > %u)\n",
+ printk(KERN_ERR "bio too big device %s (%u > %u)\n",
bdevname(bio->bi_bdev, b),
bio_sectors(bio),
q->max_hw_sectors);
} while (bio);
current->bio_tail = NULL; /* deactivate */
}
-
EXPORT_SYMBOL(generic_make_request);
/**
current->comm, task_pid_nr(current),
(rw & WRITE) ? "WRITE" : "READ",
(unsigned long long)bio->bi_sector,
- bdevname(bio->bi_bdev,b));
+ bdevname(bio->bi_bdev, b));
}
}
generic_make_request(bio);
}
-
EXPORT_SYMBOL(submit_bio);
-static void blk_recalc_rq_sectors(struct request *rq, int nsect)
-{
- if (blk_fs_request(rq)) {
- rq->hard_sector += nsect;
- rq->hard_nr_sectors -= nsect;
-
- /*
- * Move the I/O submission pointers ahead if required.
- */
- if ((rq->nr_sectors >= rq->hard_nr_sectors) &&
- (rq->sector <= rq->hard_sector)) {
- rq->sector = rq->hard_sector;
- rq->nr_sectors = rq->hard_nr_sectors;
- rq->hard_cur_sectors = bio_cur_sectors(rq->bio);
- rq->current_nr_sectors = rq->hard_cur_sectors;
- rq->buffer = bio_data(rq->bio);
- }
-
- /*
- * if total number of sectors is less than the first segment
- * size, something has gone terribly wrong
- */
- if (rq->nr_sectors < rq->current_nr_sectors) {
- printk("blk: request botched\n");
- rq->nr_sectors = rq->current_nr_sectors;
- }
- }
-}
-
/**
* __end_that_request_first - end I/O on a request
* @req: the request being processed
if (!blk_pc_request(req))
req->errors = 0;
- if (error) {
- if (blk_fs_request(req) && !(req->cmd_flags & REQ_QUIET))
- printk("end_request: I/O error, dev %s, sector %llu\n",
+ if (error && (blk_fs_request(req) && !(req->cmd_flags & REQ_QUIET))) {
+ printk(KERN_ERR "end_request: I/O error, dev %s, sector %llu\n",
req->rq_disk ? req->rq_disk->disk_name : "?",
(unsigned long long)req->sector);
}
if (blk_fs_request(req) && req->rq_disk) {
+ struct hd_struct *part = get_part(req->rq_disk, req->sector);
const int rw = rq_data_dir(req);
- disk_stat_add(req->rq_disk, sectors[rw], nr_bytes >> 9);
+ all_stat_add(req->rq_disk, part, sectors[rw],
+ nr_bytes >> 9, req->sector);
}
total_bytes = bio_nbytes = 0;
if (unlikely(bio->bi_idx >= bio->bi_vcnt)) {
blk_dump_rq_flags(req, "__end_that");
- printk("%s: bio idx %d >= vcnt %d\n",
- __FUNCTION__,
- bio->bi_idx, bio->bi_vcnt);
+ printk(KERN_ERR "%s: bio idx %d >= vcnt %d\n",
+ __func__, bio->bi_idx, bio->bi_vcnt);
break;
}
total_bytes += nbytes;
nr_bytes -= nbytes;
- if ((bio = req->bio)) {
+ bio = req->bio;
+ if (bio) {
/*
* end more in this run, or just return 'not-done'
*/
local_irq_enable();
while (!list_empty(&local_list)) {
- struct request *rq = list_entry(local_list.next, struct request, donelist);
+ struct request *rq;
+ rq = list_entry(local_list.next, struct request, donelist);
list_del_init(&rq->donelist);
rq->q->softirq_done_fn(rq);
}
}
-static int __cpuinit blk_cpu_notify(struct notifier_block *self, unsigned long action,
- void *hcpu)
+static int __cpuinit blk_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
{
/*
* If a CPU goes away, splice its entries to the current CPU
unsigned long flags;
BUG_ON(!req->q->softirq_done_fn);
-
+
local_irq_save(flags);
cpu_list = &__get_cpu_var(blk_cpu_done);
local_irq_restore(flags);
}
-
EXPORT_SYMBOL(blk_complete_request);
-
+
/*
* queue lock must be held
*/
if (disk && blk_fs_request(req) && req != &req->q->bar_rq) {
unsigned long duration = jiffies - req->start_time;
const int rw = rq_data_dir(req);
+ struct hd_struct *part = get_part(disk, req->sector);
- __disk_stat_inc(disk, ios[rw]);
- __disk_stat_add(disk, ticks[rw], duration);
+ __all_stat_inc(disk, part, ios[rw], req->sector);
+ __all_stat_add(disk, part, ticks[rw], duration, req->sector);
disk_round_stats(disk);
disk->in_flight--;
+ if (part) {
+ part_round_stats(part);
+ part->in_flight--;
+ }
}
if (req->end_io)
/**
* blk_rq_bytes - Returns bytes left to complete in the entire request
+ * @rq: the request being processed
**/
unsigned int blk_rq_bytes(struct request *rq)
{
/**
* blk_rq_cur_bytes - Returns bytes left to complete in the current segment
+ * @rq: the request being processed
**/
unsigned int blk_rq_cur_bytes(struct request *rq)
{
* 0 - we are done with this request
* 1 - this request is not freed yet, it still has pending buffers.
**/
-static int blk_end_io(struct request *rq, int error, int nr_bytes,
- int bidi_bytes, int (drv_callback)(struct request *))
+static int blk_end_io(struct request *rq, int error, unsigned int nr_bytes,
+ unsigned int bidi_bytes,
+ int (drv_callback)(struct request *))
{
struct request_queue *q = rq->q;
unsigned long flags = 0UL;
* 0 - we are done with this request
* 1 - still buffers pending for this request
**/
-int blk_end_request(struct request *rq, int error, int nr_bytes)
+int blk_end_request(struct request *rq, int error, unsigned int nr_bytes)
{
return blk_end_io(rq, error, nr_bytes, 0, NULL);
}
* 0 - we are done with this request
* 1 - still buffers pending for this request
**/
-int __blk_end_request(struct request *rq, int error, int nr_bytes)
+int __blk_end_request(struct request *rq, int error, unsigned int nr_bytes)
{
if (blk_fs_request(rq) || blk_pc_request(rq)) {
if (__end_that_request_first(rq, error, nr_bytes))
* 0 - we are done with this request
* 1 - still buffers pending for this request
**/
-int blk_end_bidi_request(struct request *rq, int error, int nr_bytes,
- int bidi_bytes)
+int blk_end_bidi_request(struct request *rq, int error, unsigned int nr_bytes,
+ unsigned int bidi_bytes)
{
return blk_end_io(rq, error, nr_bytes, bidi_bytes, NULL);
}
* this request still has pending buffers or
* the driver doesn't want to finish this request yet.
**/
-int blk_end_request_callback(struct request *rq, int error, int nr_bytes,
+int blk_end_request_callback(struct request *rq, int error,
+ unsigned int nr_bytes,
int (drv_callback)(struct request *))
{
return blk_end_io(rq, error, nr_bytes, 0, drv_callback);
{
return queue_work(kblockd_workqueue, work);
}
-
EXPORT_SYMBOL(kblockd_schedule_work);
void kblockd_flush_work(struct work_struct *work)