return 0;
}
+EXPORT_SYMBOL(blk_queue_resize_tags);
+
/**
* blk_queue_end_tag - end tag operations for a request
* @q: the request queue for the device
void blk_recount_segments(request_queue_t *q, struct bio *bio)
{
struct bio_vec *bv, *bvprv = NULL;
- int i, nr_phys_segs, nr_hw_segs, seg_size, cluster;
+ int i, nr_phys_segs, nr_hw_segs, seg_size, hw_seg_size, cluster;
int high, highprv = 1;
if (unlikely(!bio->bi_io_vec))
return;
cluster = q->queue_flags & (1 << QUEUE_FLAG_CLUSTER);
- seg_size = nr_phys_segs = nr_hw_segs = 0;
+ hw_seg_size = seg_size = nr_phys_segs = nr_hw_segs = 0;
bio_for_each_segment(bv, bio, i) {
/*
* the trick here is making sure that a high page is never
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))
+ 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 (hw_seg_size > bio->bi_hw_front_size)
+ 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 (hw_seg_size > bio->bi_hw_back_size)
+ bio->bi_hw_back_size = hw_seg_size;
+ if (nr_hw_segs == 1 && hw_seg_size > bio->bi_hw_front_size)
+ bio->bi_hw_front_size = hw_seg_size;
bio->bi_phys_segments = nr_phys_segs;
bio->bi_hw_segments = nr_hw_segs;
bio->bi_flags |= (1 << BIO_SEG_VALID);
int blk_hw_contig_segment(request_queue_t *q, struct bio *bio,
struct bio *nxt)
{
- if (!(q->queue_flags & (1 << QUEUE_FLAG_CLUSTER)))
- return 0;
-
- if (!BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(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_front_size + bio->bi_hw_back_size))
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;
+ return 1;
}
EXPORT_SYMBOL(blk_hw_contig_segment);
if (req->nr_phys_segments + nr_phys_segs > q->max_phys_segments) {
req->flags |= REQ_NOMERGE;
- q->last_merge = NULL;
+ if (req == q->last_merge)
+ q->last_merge = NULL;
return 0;
}
if (req->nr_hw_segments + nr_hw_segs > q->max_hw_segments
|| req->nr_phys_segments + nr_phys_segs > q->max_phys_segments) {
req->flags |= REQ_NOMERGE;
- q->last_merge = NULL;
+ if (req == q->last_merge)
+ q->last_merge = NULL;
return 0;
}
static int ll_back_merge_fn(request_queue_t *q, struct request *req,
struct bio *bio)
{
+ int len;
+
if (req->nr_sectors + bio_sectors(bio) > q->max_sectors) {
req->flags |= REQ_NOMERGE;
- q->last_merge = NULL;
+ if (req == q->last_merge)
+ q->last_merge = NULL;
return 0;
}
-
- if (BIOVEC_VIRT_MERGEABLE(__BVEC_END(req->biotail), __BVEC_START(bio)))
- return ll_new_mergeable(q, req, bio);
+ 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(request_queue_t *q, struct request *req,
struct bio *bio)
{
+ int len;
+
if (req->nr_sectors + bio_sectors(bio) > q->max_sectors) {
req->flags |= REQ_NOMERGE;
- q->last_merge = NULL;
+ if (req == q->last_merge)
+ q->last_merge = NULL;
return 0;
}
-
- if (BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(req->bio)))
- return ll_new_mergeable(q, req, bio);
+ 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);
}
return 0;
total_hw_segments = req->nr_hw_segments + next->nr_hw_segments;
- if (blk_hw_contig_segment(q, req->biotail, next->bio))
+ 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;
/*
* remove the plug and let it rip..
*/
-static inline void __generic_unplug_device(request_queue_t *q)
+void __generic_unplug_device(request_queue_t *q)
{
if (test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags))
return;
if (elv_next_request(q))
q->request_fn(q);
}
+EXPORT_SYMBOL(__generic_unplug_device);
/**
* generic_unplug_device - fire a request queue
printk("Using %s io scheduler\n", chosen_elevator->elevator_name);
}
- if (elevator_init(q, chosen_elevator))
- goto out_elv;
-
q->request_fn = rfn;
q->back_merge_fn = ll_back_merge_fn;
q->front_merge_fn = ll_front_merge_fn;
blk_queue_max_hw_segments(q, MAX_HW_SEGMENTS);
blk_queue_max_phys_segments(q, MAX_PHYS_SEGMENTS);
- return q;
-out_elv:
+ /*
+ * all done
+ */
+ if (!elevator_init(q, chosen_elevator))
+ return q;
+
blk_cleanup_queue(q);
out_init:
kmem_cache_free(requestq_cachep, q);
*
* A matching blk_rq_unmap_user() must be issued at the end of io, while
* still in process context.
+ *
+ * Note: The mapped bio may need to be bounced through blk_queue_bounce()
+ * before being submitted to the device, as pages mapped may be out of
+ * reach. It's the callers responsibility to make sure this happens. The
+ * original bio must be passed back in to blk_rq_unmap_user() for proper
+ * unmapping.
*/
struct request *blk_rq_map_user(request_queue_t *q, int rw, void __user *ubuf,
unsigned int len)
{
- struct request *rq = NULL;
- char *buf = NULL;
+ unsigned long uaddr;
+ struct request *rq;
struct bio *bio;
- int ret;
+
+ if (len > (q->max_sectors << 9))
+ return ERR_PTR(-EINVAL);
+ if ((!len && ubuf) || (len && !ubuf))
+ return ERR_PTR(-EINVAL);
rq = blk_get_request(q, rw, __GFP_WAIT);
if (!rq)
return ERR_PTR(-ENOMEM);
- bio = bio_map_user(q, NULL, (unsigned long) ubuf, len, rw == READ);
- if (!bio) {
- int bytes = (len + 511) & ~511;
-
- buf = kmalloc(bytes, q->bounce_gfp | GFP_USER);
- if (!buf) {
- ret = -ENOMEM;
- goto fault;
- }
-
- if (rw == WRITE) {
- if (copy_from_user(buf, ubuf, len)) {
- ret = -EFAULT;
- goto fault;
- }
- } else
- memset(buf, 0, len);
- }
+ /*
+ * if alignment requirement is satisfied, map in user pages for
+ * direct dma. else, set up kernel bounce buffers
+ */
+ uaddr = (unsigned long) ubuf;
+ if (!(uaddr & queue_dma_alignment(q)) && !(len & queue_dma_alignment(q)))
+ bio = bio_map_user(q, NULL, uaddr, len, rw == READ);
+ else
+ bio = bio_copy_user(q, uaddr, len, rw == READ);
- rq->bio = rq->biotail = bio;
- if (rq->bio)
+ if (!IS_ERR(bio)) {
+ rq->bio = rq->biotail = bio;
blk_rq_bio_prep(q, rq, bio);
- rq->buffer = rq->data = buf;
- rq->data_len = len;
- return rq;
-fault:
- if (buf)
- kfree(buf);
- if (bio)
- bio_unmap_user(bio, 1);
- if (rq)
- blk_put_request(rq);
+ rq->buffer = rq->data = NULL;
+ rq->data_len = len;
+ return rq;
+ }
- return ERR_PTR(ret);
+ /*
+ * bio is the err-ptr
+ */
+ blk_put_request(rq);
+ return (struct request *) bio;
}
EXPORT_SYMBOL(blk_rq_map_user);
* Description:
* Unmap a request previously mapped by blk_rq_map_user().
*/
-int blk_rq_unmap_user(struct request *rq, void __user *ubuf, struct bio *bio,
- unsigned int ulen)
+int blk_rq_unmap_user(struct request *rq, struct bio *bio, unsigned int ulen)
{
- const int read = rq_data_dir(rq) == READ;
int ret = 0;
- if (bio)
- bio_unmap_user(bio, read);
- if (rq->buffer) {
- if (read && copy_to_user(ubuf, rq->buffer, ulen))
- ret = -EFAULT;
- kfree(rq->buffer);
+ if (bio) {
+ if (bio_flagged(bio, BIO_USER_MAPPED))
+ bio_unmap_user(bio);
+ else
+ ret = bio_uncopy_user(bio);
}
blk_put_request(rq);
out:
if (freereq)
__blk_put_request(q, freereq);
+ if (bio_sync(bio))
+ __generic_unplug_device(q);
- if (blk_queue_plugged(q)) {
- int nrq = q->rq.count[READ] + q->rq.count[WRITE] - q->in_flight;
-
- if (nrq == q->unplug_thresh || bio_sync(bio))
- __generic_unplug_device(q);
- }
spin_unlock_irq(q->queue_lock);
return 0;
void blk_recalc_rq_segments(struct request *rq)
{
- struct bio *bio;
+ struct bio *bio, *prevbio = NULL;
int nr_phys_segs, nr_hw_segs;
if (!rq->bio)
nr_phys_segs += bio_phys_segments(rq->q, bio);
nr_hw_segs += bio_hw_segments(rq->q, bio);
+ if (prevbio) {
+ if (blk_phys_contig_segment(rq->q, prevbio, bio))
+ nr_phys_segs--;
+ if (blk_hw_contig_segment(rq->q, prevbio, bio))
+ nr_hw_segs--;
+ }
+ prevbio = bio;
}
rq->nr_phys_segments = nr_phys_segs;
}
total_bytes = bio_nbytes = 0;
- while ((bio = req->bio)) {
+ while ((bio = req->bio) != NULL) {
int nbytes;
if (nr_bytes >= bio->bi_size) {
return queue_work(kblockd_workqueue, work);
}
+EXPORT_SYMBOL(kblockd_schedule_work);
+
void kblockd_flush(void)
{
flush_workqueue(kblockd_workqueue);
git://git.onelab.eu / linux-2.6.git / blobdiff