static void blk_unplug_work(struct work_struct *work);
static void blk_unplug_timeout(unsigned long data);
-static void drive_stat_acct(struct request *rq, int nr_sectors, int new_io);
+static void drive_stat_acct(struct request *rq, int new_io);
static void init_request_from_bio(struct request *req, struct bio *bio);
static int __make_request(struct request_queue *q, struct bio *bio);
static struct io_context *current_io_context(gfp_t gfp_flags, int node);
retval = atomic_dec_and_test(&bqt->refcnt);
if (retval) {
BUG_ON(bqt->busy);
- BUG_ON(!list_empty(&bqt->busy_list));
kfree(bqt->tag_index);
bqt->tag_index = NULL;
if (init_tag_map(q, tags, depth))
goto fail;
- INIT_LIST_HEAD(&tags->busy_list);
tags->busy = 0;
atomic_set(&tags->refcnt, 1);
return tags;
*/
q->queue_tags = tags;
q->queue_flags |= (1 << QUEUE_FLAG_QUEUED);
+ INIT_LIST_HEAD(&q->tag_busy_list);
return 0;
fail:
kfree(tags);
bqt->tag_index[tag] = NULL;
- /*
- * We use test_and_clear_bit's memory ordering properties here.
- * The tag_map bit acts as a lock for tag_index[bit], so we need
- * a barrer before clearing the bit (precisely: release semantics).
- * Could use clear_bit_unlock when it is merged.
- */
- if (unlikely(!test_and_clear_bit(tag, bqt->tag_map))) {
+ if (unlikely(!test_bit(tag, bqt->tag_map))) {
printk(KERN_ERR "%s: attempt to clear non-busy tag (%d)\n",
__FUNCTION__, tag);
return;
}
-
+ /*
+ * The tag_map bit acts as a lock for tag_index[bit], so we need
+ * unlock memory barrier semantics.
+ */
+ clear_bit_unlock(tag, bqt->tag_map);
bqt->busy--;
}
if (tag >= bqt->max_depth)
return 1;
- } while (test_and_set_bit(tag, bqt->tag_map));
+ } while (test_and_set_bit_lock(tag, bqt->tag_map));
/*
- * We rely on test_and_set_bit providing lock memory ordering semantics
- * (could use test_and_set_bit_lock when it is merged).
+ * We need lock ordering semantics given by test_and_set_bit_lock.
+ * See blk_queue_end_tag for details.
*/
rq->cmd_flags |= REQ_QUEUED;
rq->tag = tag;
bqt->tag_index[tag] = rq;
blkdev_dequeue_request(rq);
- list_add(&rq->queuelist, &bqt->busy_list);
+ list_add(&rq->queuelist, &q->tag_busy_list);
bqt->busy++;
return 0;
}
**/
void blk_queue_invalidate_tags(struct request_queue *q)
{
- struct blk_queue_tag *bqt = q->queue_tags;
struct list_head *tmp, *n;
struct request *rq;
- list_for_each_safe(tmp, n, &bqt->busy_list) {
+ list_for_each_safe(tmp, n, &q->tag_busy_list) {
rq = list_entry_rq(tmp);
if (rq->tag == -1) {
struct scatterlist *sglist)
{
struct bio_vec *bvec, *bvprv;
- struct scatterlist *next_sg, *sg;
struct req_iterator iter;
+ struct scatterlist *sg;
int nsegs, cluster;
nsegs = 0;
* for each bio in rq
*/
bvprv = NULL;
- sg = next_sg = &sglist[0];
+ sg = NULL;
rq_for_each_segment(bvec, rq, iter) {
int nbytes = bvec->bv_len;
sg->length += nbytes;
} else {
new_segment:
- sg = next_sg;
- next_sg = sg_next(sg);
+ 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->page = bvec->bv_page;
- sg->length = nbytes;
- sg->offset = bvec->bv_offset;
+ sg_set_page(sg, bvec->bv_page, nbytes, bvec->bv_offset);
nsegs++;
}
bvprv = bvec;
} /* segments in rq */
+ if (sg)
+ __sg_mark_end(sg);
+
return nsegs;
}
void blk_sync_queue(struct request_queue *q)
{
del_timer_sync(&q->unplug_timer);
+ kblockd_flush_work(&q->unplug_work);
}
EXPORT_SYMBOL(blk_sync_queue);
blk_trace_shutdown(q);
+ bdi_destroy(&q->backing_dev_info);
kmem_cache_free(requestq_cachep, q);
}
struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
{
struct request_queue *q;
+ int err;
q = kmem_cache_alloc_node(requestq_cachep,
gfp_mask | __GFP_ZERO, node_id);
if (!q)
return NULL;
+ q->backing_dev_info.unplug_io_fn = blk_backing_dev_unplug;
+ q->backing_dev_info.unplug_io_data = q;
+ err = bdi_init(&q->backing_dev_info);
+ if (err) {
+ kmem_cache_free(requestq_cachep, q);
+ return NULL;
+ }
+
init_timer(&q->unplug_timer);
kobject_set_name(&q->kobj, "%s", "queue");
q->kobj.ktype = &queue_ktype;
kobject_init(&q->kobj);
- q->backing_dev_info.unplug_io_fn = blk_backing_dev_unplug;
- q->backing_dev_info.unplug_io_data = q;
-
mutex_init(&q->sysfs_lock);
return q;
if (blk_rq_tagged(rq))
blk_queue_end_tag(q, rq);
- drive_stat_acct(rq, rq->nr_sectors, 1);
+ drive_stat_acct(rq, 1);
__elv_add_request(q, rq, where, 0);
blk_start_queueing(q);
spin_unlock_irqrestore(q->queue_lock, flags);
EXPORT_SYMBOL(blkdev_issue_flush);
-static void drive_stat_acct(struct request *rq, int nr_sectors, int new_io)
+static void drive_stat_acct(struct request *rq, int new_io)
{
int rw = rq_data_dir(rq);
*/
static inline void add_request(struct request_queue * q, struct request * req)
{
- drive_stat_acct(req, req->nr_sectors, 1);
+ drive_stat_acct(req, 1);
/*
* elevator indicated where it wants this request to be
req->biotail = bio;
req->nr_sectors = req->hard_nr_sectors += nr_sectors;
req->ioprio = ioprio_best(req->ioprio, prio);
- drive_stat_acct(req, nr_sectors, 0);
+ drive_stat_acct(req, 0);
if (!attempt_back_merge(q, req))
elv_merged_request(q, req, el_ret);
goto out;
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, nr_sectors, 0);
+ drive_stat_acct(req, 0);
if (!attempt_front_merge(q, req))
elv_merged_request(q, req, el_ret);
goto out;
if (unlikely(block_dump)) {
char b[BDEVNAME_SIZE];
printk(KERN_DEBUG "%s(%d): %s block %Lu on %s\n",
- current->comm, current->pid,
+ current->comm, task_pid_nr(current),
(rw & WRITE) ? "WRITE" : "READ",
(unsigned long long)bio->bi_sector,
bdevname(bio->bi_bdev,b));
/**
* end_request - end I/O on the current segment of the request
- * @rq: the request being processed
+ * @req: the request being processed
* @uptodate: error value or 0/1 uptodate flag
*
* Description:
git.samba.org / sfrench / cifs-2.6.git / blobdiff