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);
EXPORT_SYMBOL(blk_queue_stack_limits);
+/**
+ * blk_queue_dma_drain - Set up a drain buffer for excess dma.
+ *
+ * @q: the request queue for the device
+ * @buf: physically contiguous buffer
+ * @size: size of the buffer in bytes
+ *
+ * Some devices have excess DMA problems and can't simply discard (or
+ * zero fill) the unwanted piece of the transfer. They have to have a
+ * real area of memory to transfer it into. The use case for this is
+ * ATAPI devices in DMA mode. If the packet command causes a transfer
+ * bigger than the transfer size some HBAs will lock up if there
+ * aren't DMA elements to contain the excess transfer. What this API
+ * does is adjust the queue so that the buf is always appended
+ * silently to the scatterlist.
+ *
+ * Note: This routine adjusts max_hw_segments to make room for
+ * appending the drain buffer. If you call
+ * blk_queue_max_hw_segments() or blk_queue_max_phys_segments() after
+ * calling this routine, you must set the limit to one fewer than your
+ * device can support otherwise there won't be room for the drain
+ * buffer.
+ */
+int blk_queue_dma_drain(struct request_queue *q, void *buf,
+ unsigned int size)
+{
+ if (q->max_hw_segments < 2 || q->max_phys_segments < 2)
+ return -EINVAL;
+ /* make room for appending the drain */
+ --q->max_hw_segments;
+ --q->max_phys_segments;
+ q->dma_drain_buffer = buf;
+ q->dma_drain_size = size;
+
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(blk_queue_dma_drain);
+
/**
* blk_queue_segment_boundary - set boundary rules for segment merging
* @q: the request queue for the device
EXPORT_SYMBOL(blk_queue_dma_alignment);
+/**
+ * blk_queue_update_dma_alignment - update dma length and memory alignment
+ * @q: the request queue for the device
+ * @mask: alignment mask
+ *
+ * description:
+ * update required memory and length aligment for direct dma transactions.
+ * If the requested alignment is larger than the current alignment, then
+ * the current queue alignment is updated to the new value, otherwise it
+ * is left alone. The design of this is to allow multiple objects
+ * (driver, device, transport etc) to set their respective
+ * alignments without having them interfere.
+ *
+ **/
+void blk_queue_update_dma_alignment(struct request_queue *q, int mask)
+{
+ BUG_ON(mask > PAGE_SIZE);
+
+ if (mask > q->dma_alignment)
+ q->dma_alignment = mask;
+}
+
+EXPORT_SYMBOL(blk_queue_update_dma_alignment);
+
/**
* blk_queue_find_tag - find a request by its tag and queue
* @q: The request queue for the device
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) {
- rq = list_entry_rq(tmp);
- if (rq->tag == -1) {
- printk(KERN_ERR
- "%s: bad tag found on list\n", __FUNCTION__);
- list_del_init(&rq->queuelist);
- rq->cmd_flags &= ~REQ_QUEUED;
- } else
- blk_queue_end_tag(q, rq);
-
- rq->cmd_flags &= ~REQ_STARTED;
- __elv_add_request(q, rq, ELEVATOR_INSERT_BACK, 0);
- }
+ list_for_each_safe(tmp, n, &q->tag_busy_list)
+ blk_requeue_request(q, list_entry_rq(tmp));
}
EXPORT_SYMBOL(blk_queue_invalidate_tags);
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);
+ sg_mark_end(sg);
return nsegs;
}
{
struct request_queue *q = bdi->unplug_io_data;
- /*
- * devices don't necessarily have an ->unplug_fn defined
- */
- if (q->unplug_fn) {
- blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL,
- q->rq.count[READ] + q->rq.count[WRITE]);
-
- q->unplug_fn(q);
- }
+ blk_unplug(q);
}
static void blk_unplug_work(struct work_struct *work)
kblockd_schedule_work(&q->unplug_work);
}
+void blk_unplug(struct request_queue *q)
+{
+ /*
+ * devices don't necessarily have an ->unplug_fn defined
+ */
+ if (q->unplug_fn) {
+ blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL,
+ q->rq.count[READ] + q->rq.count[WRITE]);
+
+ q->unplug_fn(q);
+ }
+}
+EXPORT_SYMBOL(blk_unplug);
+
/**
* blk_start_queue - restart a previously stopped queue
* @q: The &struct request_queue in question
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);
init_timer(&q->unplug_timer);
- kobject_set_name(&q->kobj, "%s", "queue");
- q->kobj.ktype = &queue_ktype;
- kobject_init(&q->kobj);
+ kobject_init(&q->kobj, &queue_ktype);
mutex_init(&q->sysfs_lock);
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;
sector_t old_sector;
int ret, nr_sectors = bio_sectors(bio);
dev_t old_dev;
+ int err = -EIO;
might_sleep();
bdevname(bio->bi_bdev, b),
(long long) bio->bi_sector);
end_io:
- bio_endio(bio, -EIO);
+ bio_endio(bio, err);
break;
}
if (bio_check_eod(bio, nr_sectors))
goto end_io;
+ if (bio_empty_barrier(bio) && !q->prepare_flush_fn) {
+ err = -EOPNOTSUPP;
+ goto end_io;
+ }
ret = q->make_request_fn(q, bio);
} while (ret);
return queue_var_show(max_hw_sectors_kb, (page));
}
-static ssize_t queue_max_segments_show(struct request_queue *q, char *page)
-{
- return queue_var_show(q->max_phys_segments, page);
-}
-
-static ssize_t queue_max_segments_store(struct request_queue *q,
- const char *page, size_t count)
-{
- unsigned long segments;
- ssize_t ret = queue_var_store(&segments, page, count);
- spin_lock_irq(q->queue_lock);
- q->max_phys_segments = segments;
- spin_unlock_irq(q->queue_lock);
-
- return ret;
-}
static struct queue_sysfs_entry queue_requests_entry = {
.attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR },
.show = queue_requests_show,
.show = queue_max_hw_sectors_show,
};
-static struct queue_sysfs_entry queue_max_segments_entry = {
- .attr = {.name = "max_segments", .mode = S_IRUGO | S_IWUSR },
- .show = queue_max_segments_show,
- .store = queue_max_segments_store,
-};
-
static struct queue_sysfs_entry queue_iosched_entry = {
.attr = {.name = "scheduler", .mode = S_IRUGO | S_IWUSR },
.show = elv_iosched_show,
&queue_ra_entry.attr,
&queue_max_hw_sectors_entry.attr,
&queue_max_sectors_entry.attr,
- &queue_max_segments_entry.attr,
&queue_iosched_entry.attr,
NULL,
};
if (!q || !q->request_fn)
return -ENXIO;
- q->kobj.parent = kobject_get(&disk->kobj);
-
- ret = kobject_add(&q->kobj);
+ ret = kobject_add(&q->kobj, kobject_get(&disk->dev.kobj),
+ "%s", "queue");
if (ret < 0)
return ret;
kobject_uevent(&q->kobj, KOBJ_REMOVE);
kobject_del(&q->kobj);
- kobject_put(&disk->kobj);
+ kobject_put(&disk->dev.kobj);
}
}
projects / linux-2.6-omap-h63xx.git / blobdiff