Commit dece1635 authored by Jens Axboe's avatar Jens Axboe

block: change ->make_request_fn() and users to return a queue cookie

No functional changes in this patch, but it prepares us for returning
a more useful cookie related to the IO that was queued up.
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
Acked-by: default avatarChristoph Hellwig <hch@lst.de>
Acked-by: default avatarKeith Busch <keith.busch@intel.com>
parent 8e483ed1
......@@ -59,7 +59,7 @@ struct nfhd_device {
struct gendisk *disk;
};
static void nfhd_make_request(struct request_queue *queue, struct bio *bio)
static blk_qc_t nfhd_make_request(struct request_queue *queue, struct bio *bio)
{
struct nfhd_device *dev = queue->queuedata;
struct bio_vec bvec;
......@@ -77,6 +77,7 @@ static void nfhd_make_request(struct request_queue *queue, struct bio *bio)
sec += len;
}
bio_endio(bio);
return BLK_QC_T_NONE;
}
static int nfhd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
......
......@@ -103,7 +103,7 @@ axon_ram_irq_handler(int irq, void *dev)
* axon_ram_make_request - make_request() method for block device
* @queue, @bio: see blk_queue_make_request()
*/
static void
static blk_qc_t
axon_ram_make_request(struct request_queue *queue, struct bio *bio)
{
struct axon_ram_bank *bank = bio->bi_bdev->bd_disk->private_data;
......@@ -120,7 +120,7 @@ axon_ram_make_request(struct request_queue *queue, struct bio *bio)
bio_for_each_segment(vec, bio, iter) {
if (unlikely(phys_mem + vec.bv_len > phys_end)) {
bio_io_error(bio);
return;
return BLK_QC_T_NONE;
}
user_mem = page_address(vec.bv_page) + vec.bv_offset;
......@@ -133,6 +133,7 @@ axon_ram_make_request(struct request_queue *queue, struct bio *bio)
transfered += vec.bv_len;
}
bio_endio(bio);
return BLK_QC_T_NONE;
}
/**
......
......@@ -101,7 +101,7 @@ static void simdisk_transfer(struct simdisk *dev, unsigned long sector,
spin_unlock(&dev->lock);
}
static void simdisk_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t simdisk_make_request(struct request_queue *q, struct bio *bio)
{
struct simdisk *dev = q->queuedata;
struct bio_vec bvec;
......@@ -119,6 +119,7 @@ static void simdisk_make_request(struct request_queue *q, struct bio *bio)
}
bio_endio(bio);
return BLK_QC_T_NONE;
}
static int simdisk_open(struct block_device *bdev, fmode_t mode)
......
......@@ -809,7 +809,7 @@ blk_init_queue_node(request_fn_proc *rfn, spinlock_t *lock, int node_id)
}
EXPORT_SYMBOL(blk_init_queue_node);
static void blk_queue_bio(struct request_queue *q, struct bio *bio);
static blk_qc_t blk_queue_bio(struct request_queue *q, struct bio *bio);
struct request_queue *
blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn,
......@@ -1678,7 +1678,7 @@ void init_request_from_bio(struct request *req, struct bio *bio)
blk_rq_bio_prep(req->q, req, bio);
}
static void blk_queue_bio(struct request_queue *q, struct bio *bio)
static blk_qc_t blk_queue_bio(struct request_queue *q, struct bio *bio)
{
const bool sync = !!(bio->bi_rw & REQ_SYNC);
struct blk_plug *plug;
......@@ -1698,7 +1698,7 @@ static void blk_queue_bio(struct request_queue *q, struct bio *bio)
if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) {
bio->bi_error = -EIO;
bio_endio(bio);
return;
return BLK_QC_T_NONE;
}
if (bio->bi_rw & (REQ_FLUSH | REQ_FUA)) {
......@@ -1713,7 +1713,7 @@ static void blk_queue_bio(struct request_queue *q, struct bio *bio)
*/
if (!blk_queue_nomerges(q)) {
if (blk_attempt_plug_merge(q, bio, &request_count, NULL))
return;
return BLK_QC_T_NONE;
} else
request_count = blk_plug_queued_count(q);
......@@ -1791,6 +1791,8 @@ static void blk_queue_bio(struct request_queue *q, struct bio *bio)
out_unlock:
spin_unlock_irq(q->queue_lock);
}
return BLK_QC_T_NONE;
}
/*
......@@ -1996,12 +1998,13 @@ generic_make_request_checks(struct bio *bio)
* a lower device by calling into generic_make_request recursively, which
* means the bio should NOT be touched after the call to ->make_request_fn.
*/
void generic_make_request(struct bio *bio)
blk_qc_t generic_make_request(struct bio *bio)
{
struct bio_list bio_list_on_stack;
blk_qc_t ret = BLK_QC_T_NONE;
if (!generic_make_request_checks(bio))
return;
goto out;
/*
* We only want one ->make_request_fn to be active at a time, else
......@@ -2015,7 +2018,7 @@ void generic_make_request(struct bio *bio)
*/
if (current->bio_list) {
bio_list_add(current->bio_list, bio);
return;
goto out;
}
/* following loop may be a bit non-obvious, and so deserves some
......@@ -2040,7 +2043,7 @@ void generic_make_request(struct bio *bio)
if (likely(blk_queue_enter(q, __GFP_WAIT) == 0)) {
q->make_request_fn(q, bio);
ret = q->make_request_fn(q, bio);
blk_queue_exit(q);
......@@ -2053,6 +2056,9 @@ void generic_make_request(struct bio *bio)
}
} while (bio);
current->bio_list = NULL; /* deactivate */
out:
return ret;
}
EXPORT_SYMBOL(generic_make_request);
......@@ -2066,7 +2072,7 @@ EXPORT_SYMBOL(generic_make_request);
* interfaces; @bio must be presetup and ready for I/O.
*
*/
void submit_bio(int rw, struct bio *bio)
blk_qc_t submit_bio(int rw, struct bio *bio)
{
bio->bi_rw |= rw;
......@@ -2100,7 +2106,7 @@ void submit_bio(int rw, struct bio *bio)
}
}
generic_make_request(bio);
return generic_make_request(bio);
}
EXPORT_SYMBOL(submit_bio);
......
......@@ -1235,7 +1235,7 @@ static int blk_mq_direct_issue_request(struct request *rq)
* but will attempt to bypass the hctx queueing if we can go straight to
* hardware for SYNC IO.
*/
static void blk_mq_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
{
const int is_sync = rw_is_sync(bio->bi_rw);
const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA);
......@@ -1249,7 +1249,7 @@ static void blk_mq_make_request(struct request_queue *q, struct bio *bio)
if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) {
bio_io_error(bio);
return;
return BLK_QC_T_NONE;
}
blk_queue_split(q, &bio, q->bio_split);
......@@ -1257,13 +1257,13 @@ static void blk_mq_make_request(struct request_queue *q, struct bio *bio)
if (!is_flush_fua && !blk_queue_nomerges(q)) {
if (blk_attempt_plug_merge(q, bio, &request_count,
&same_queue_rq))
return;
return BLK_QC_T_NONE;
} else
request_count = blk_plug_queued_count(q);
rq = blk_mq_map_request(q, bio, &data);
if (unlikely(!rq))
return;
return BLK_QC_T_NONE;
if (unlikely(is_flush_fua)) {
blk_mq_bio_to_request(rq, bio);
......@@ -1302,11 +1302,11 @@ static void blk_mq_make_request(struct request_queue *q, struct bio *bio)
old_rq = rq;
blk_mq_put_ctx(data.ctx);
if (!old_rq)
return;
return BLK_QC_T_NONE;
if (!blk_mq_direct_issue_request(old_rq))
return;
return BLK_QC_T_NONE;
blk_mq_insert_request(old_rq, false, true, true);
return;
return BLK_QC_T_NONE;
}
if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) {
......@@ -1320,13 +1320,14 @@ static void blk_mq_make_request(struct request_queue *q, struct bio *bio)
blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua);
}
blk_mq_put_ctx(data.ctx);
return BLK_QC_T_NONE;
}
/*
* Single hardware queue variant. This will attempt to use any per-process
* plug for merging and IO deferral.
*/
static void blk_sq_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t blk_sq_make_request(struct request_queue *q, struct bio *bio)
{
const int is_sync = rw_is_sync(bio->bi_rw);
const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA);
......@@ -1339,18 +1340,18 @@ static void blk_sq_make_request(struct request_queue *q, struct bio *bio)
if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) {
bio_io_error(bio);
return;
return BLK_QC_T_NONE;
}
blk_queue_split(q, &bio, q->bio_split);
if (!is_flush_fua && !blk_queue_nomerges(q) &&
blk_attempt_plug_merge(q, bio, &request_count, NULL))
return;
return BLK_QC_T_NONE;
rq = blk_mq_map_request(q, bio, &data);
if (unlikely(!rq))
return;
return BLK_QC_T_NONE;
if (unlikely(is_flush_fua)) {
blk_mq_bio_to_request(rq, bio);
......@@ -1374,7 +1375,7 @@ static void blk_sq_make_request(struct request_queue *q, struct bio *bio)
}
list_add_tail(&rq->queuelist, &plug->mq_list);
blk_mq_put_ctx(data.ctx);
return;
return BLK_QC_T_NONE;
}
if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) {
......@@ -1389,6 +1390,7 @@ static void blk_sq_make_request(struct request_queue *q, struct bio *bio)
}
blk_mq_put_ctx(data.ctx);
return BLK_QC_T_NONE;
}
/*
......
......@@ -323,7 +323,7 @@ static int brd_do_bvec(struct brd_device *brd, struct page *page,
return err;
}
static void brd_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t brd_make_request(struct request_queue *q, struct bio *bio)
{
struct block_device *bdev = bio->bi_bdev;
struct brd_device *brd = bdev->bd_disk->private_data;
......@@ -358,9 +358,10 @@ static void brd_make_request(struct request_queue *q, struct bio *bio)
out:
bio_endio(bio);
return;
return BLK_QC_T_NONE;
io_error:
bio_io_error(bio);
return BLK_QC_T_NONE;
}
static int brd_rw_page(struct block_device *bdev, sector_t sector,
......
......@@ -1448,7 +1448,7 @@ extern int proc_details;
/* drbd_req */
extern void do_submit(struct work_struct *ws);
extern void __drbd_make_request(struct drbd_device *, struct bio *, unsigned long);
extern void drbd_make_request(struct request_queue *q, struct bio *bio);
extern blk_qc_t drbd_make_request(struct request_queue *q, struct bio *bio);
extern int drbd_read_remote(struct drbd_device *device, struct drbd_request *req);
extern int is_valid_ar_handle(struct drbd_request *, sector_t);
......
......@@ -1494,7 +1494,7 @@ void do_submit(struct work_struct *ws)
}
}
void drbd_make_request(struct request_queue *q, struct bio *bio)
blk_qc_t drbd_make_request(struct request_queue *q, struct bio *bio)
{
struct drbd_device *device = (struct drbd_device *) q->queuedata;
unsigned long start_jif;
......@@ -1510,6 +1510,7 @@ void drbd_make_request(struct request_queue *q, struct bio *bio)
inc_ap_bio(device);
__drbd_make_request(device, bio, start_jif);
return BLK_QC_T_NONE;
}
void request_timer_fn(unsigned long data)
......
......@@ -321,7 +321,7 @@ static struct nullb_queue *nullb_to_queue(struct nullb *nullb)
return &nullb->queues[index];
}
static void null_queue_bio(struct request_queue *q, struct bio *bio)
static blk_qc_t null_queue_bio(struct request_queue *q, struct bio *bio)
{
struct nullb *nullb = q->queuedata;
struct nullb_queue *nq = nullb_to_queue(nullb);
......@@ -331,6 +331,7 @@ static void null_queue_bio(struct request_queue *q, struct bio *bio)
cmd->bio = bio;
null_handle_cmd(cmd);
return BLK_QC_T_NONE;
}
static int null_rq_prep_fn(struct request_queue *q, struct request *req)
......
......@@ -2441,7 +2441,7 @@ static void pkt_make_request_write(struct request_queue *q, struct bio *bio)
}
}
static void pkt_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t pkt_make_request(struct request_queue *q, struct bio *bio)
{
struct pktcdvd_device *pd;
char b[BDEVNAME_SIZE];
......@@ -2467,7 +2467,7 @@ static void pkt_make_request(struct request_queue *q, struct bio *bio)
*/
if (bio_data_dir(bio) == READ) {
pkt_make_request_read(pd, bio);
return;
return BLK_QC_T_NONE;
}
if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
......@@ -2499,13 +2499,12 @@ static void pkt_make_request(struct request_queue *q, struct bio *bio)
pkt_make_request_write(q, split);
} while (split != bio);
return;
return BLK_QC_T_NONE;
end_io:
bio_io_error(bio);
return BLK_QC_T_NONE;
}
static void pkt_init_queue(struct pktcdvd_device *pd)
{
struct request_queue *q = pd->disk->queue;
......
......@@ -598,7 +598,7 @@ static struct bio *ps3vram_do_bio(struct ps3_system_bus_device *dev,
return next;
}
static void ps3vram_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t ps3vram_make_request(struct request_queue *q, struct bio *bio)
{
struct ps3_system_bus_device *dev = q->queuedata;
struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
......@@ -614,11 +614,13 @@ static void ps3vram_make_request(struct request_queue *q, struct bio *bio)
spin_unlock_irq(&priv->lock);
if (busy)
return;
return BLK_QC_T_NONE;
do {
bio = ps3vram_do_bio(dev, bio);
} while (bio);
return BLK_QC_T_NONE;
}
static int ps3vram_probe(struct ps3_system_bus_device *dev)
......
......@@ -145,7 +145,7 @@ static void bio_dma_done_cb(struct rsxx_cardinfo *card,
}
}
static void rsxx_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t rsxx_make_request(struct request_queue *q, struct bio *bio)
{
struct rsxx_cardinfo *card = q->queuedata;
struct rsxx_bio_meta *bio_meta;
......@@ -199,7 +199,7 @@ static void rsxx_make_request(struct request_queue *q, struct bio *bio)
if (st)
goto queue_err;
return;
return BLK_QC_T_NONE;
queue_err:
kmem_cache_free(bio_meta_pool, bio_meta);
......@@ -207,6 +207,7 @@ static void rsxx_make_request(struct request_queue *q, struct bio *bio)
if (st)
bio->bi_error = st;
bio_endio(bio);
return BLK_QC_T_NONE;
}
/*----------------- Device Setup -------------------*/
......
......@@ -524,7 +524,7 @@ static int mm_check_plugged(struct cardinfo *card)
return !!blk_check_plugged(mm_unplug, card, sizeof(struct blk_plug_cb));
}
static void mm_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t mm_make_request(struct request_queue *q, struct bio *bio)
{
struct cardinfo *card = q->queuedata;
pr_debug("mm_make_request %llu %u\n",
......@@ -541,7 +541,7 @@ static void mm_make_request(struct request_queue *q, struct bio *bio)
activate(card);
spin_unlock_irq(&card->lock);
return;
return BLK_QC_T_NONE;
}
static irqreturn_t mm_interrupt(int irq, void *__card)
......
......@@ -894,7 +894,7 @@ static void __zram_make_request(struct zram *zram, struct bio *bio)
/*
* Handler function for all zram I/O requests.
*/
static void zram_make_request(struct request_queue *queue, struct bio *bio)
static blk_qc_t zram_make_request(struct request_queue *queue, struct bio *bio)
{
struct zram *zram = queue->queuedata;
......@@ -911,11 +911,12 @@ static void zram_make_request(struct request_queue *queue, struct bio *bio)
__zram_make_request(zram, bio);
zram_meta_put(zram);
return;
return BLK_QC_T_NONE;
put_zram:
zram_meta_put(zram);
error:
bio_io_error(bio);
return BLK_QC_T_NONE;
}
static void zram_slot_free_notify(struct block_device *bdev,
......
......@@ -803,7 +803,7 @@ static int rrpc_submit_io(struct rrpc *rrpc, struct bio *bio,
return NVM_IO_OK;
}
static void rrpc_make_rq(struct request_queue *q, struct bio *bio)
static blk_qc_t rrpc_make_rq(struct request_queue *q, struct bio *bio)
{
struct rrpc *rrpc = q->queuedata;
struct nvm_rq *rqd;
......@@ -811,21 +811,21 @@ static void rrpc_make_rq(struct request_queue *q, struct bio *bio)
if (bio->bi_rw & REQ_DISCARD) {
rrpc_discard(rrpc, bio);
return;
return BLK_QC_T_NONE;
}
rqd = mempool_alloc(rrpc->rq_pool, GFP_KERNEL);
if (!rqd) {
pr_err_ratelimited("rrpc: not able to queue bio.");
bio_io_error(bio);
return;
return BLK_QC_T_NONE;
}
memset(rqd, 0, sizeof(struct nvm_rq));
err = rrpc_submit_io(rrpc, bio, rqd, NVM_IOTYPE_NONE);
switch (err) {
case NVM_IO_OK:
return;
return BLK_QC_T_NONE;
case NVM_IO_ERR:
bio_io_error(bio);
break;
......@@ -841,6 +841,7 @@ static void rrpc_make_rq(struct request_queue *q, struct bio *bio)
}
mempool_free(rqd, rrpc->rq_pool);
return BLK_QC_T_NONE;
}
static void rrpc_requeue(struct work_struct *work)
......
......@@ -958,7 +958,8 @@ static void cached_dev_nodata(struct closure *cl)
/* Cached devices - read & write stuff */
static void cached_dev_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t cached_dev_make_request(struct request_queue *q,
struct bio *bio)
{
struct search *s;
struct bcache_device *d = bio->bi_bdev->bd_disk->private_data;
......@@ -997,6 +998,8 @@ static void cached_dev_make_request(struct request_queue *q, struct bio *bio)
else
generic_make_request(bio);
}
return BLK_QC_T_NONE;
}
static int cached_dev_ioctl(struct bcache_device *d, fmode_t mode,
......@@ -1070,7 +1073,8 @@ static void flash_dev_nodata(struct closure *cl)
continue_at(cl, search_free, NULL);
}
static void flash_dev_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t flash_dev_make_request(struct request_queue *q,
struct bio *bio)
{
struct search *s;
struct closure *cl;
......@@ -1093,7 +1097,7 @@ static void flash_dev_make_request(struct request_queue *q, struct bio *bio)
continue_at_nobarrier(&s->cl,
flash_dev_nodata,
bcache_wq);
return;
return BLK_QC_T_NONE;
} else if (rw) {
bch_keybuf_check_overlapping(&s->iop.c->moving_gc_keys,
&KEY(d->id, bio->bi_iter.bi_sector, 0),
......@@ -1109,6 +1113,7 @@ static void flash_dev_make_request(struct request_queue *q, struct bio *bio)
}
continue_at(cl, search_free, NULL);
return BLK_QC_T_NONE;
}
static int flash_dev_ioctl(struct bcache_device *d, fmode_t mode,
......
......@@ -1755,7 +1755,7 @@ static void __split_and_process_bio(struct mapped_device *md,
* The request function that just remaps the bio built up by
* dm_merge_bvec.
*/
static void dm_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio)
{
int rw = bio_data_dir(bio);
struct mapped_device *md = q->queuedata;
......@@ -1774,12 +1774,12 @@ static void dm_make_request(struct request_queue *q, struct bio *bio)
queue_io(md, bio);
else
bio_io_error(bio);
return;
return BLK_QC_T_NONE;
}
__split_and_process_bio(md, map, bio);
dm_put_live_table(md, srcu_idx);
return;
return BLK_QC_T_NONE;
}
int dm_request_based(struct mapped_device *md)
......
......@@ -250,7 +250,7 @@ static DEFINE_SPINLOCK(all_mddevs_lock);
* call has finished, the bio has been linked into some internal structure
* and so is visible to ->quiesce(), so we don't need the refcount any more.
*/
static void md_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t md_make_request(struct request_queue *q, struct bio *bio)
{
const int rw = bio_data_dir(bio);
struct mddev *mddev = q->queuedata;
......@@ -262,13 +262,13 @@ static void md_make_request(struct request_queue *q, struct bio *bio)
if (mddev == NULL || mddev->pers == NULL
|| !mddev->ready) {
bio_io_error(bio);
return;
return BLK_QC_T_NONE;
}
if (mddev->ro == 1 && unlikely(rw == WRITE)) {
if (bio_sectors(bio) != 0)
bio->bi_error = -EROFS;
bio_endio(bio);
return;
return BLK_QC_T_NONE;
}
smp_rmb(); /* Ensure implications of 'active' are visible */
rcu_read_lock();
......@@ -302,6 +302,8 @@ static void md_make_request(struct request_queue *q, struct bio *bio)
if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended)
wake_up(&mddev->sb_wait);
return BLK_QC_T_NONE;
}
/* mddev_suspend makes sure no new requests are submitted
......
......@@ -161,7 +161,7 @@ static int nd_blk_do_bvec(struct nd_blk_device *blk_dev,
return err;
}
static void nd_blk_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t nd_blk_make_request(struct request_queue *q, struct bio *bio)
{
struct block_device *bdev = bio->bi_bdev;
struct gendisk *disk = bdev->bd_disk;
......@@ -208,6 +208,7 @@ static void nd_blk_make_request(struct request_queue *q, struct bio *bio)
out:
bio_endio(bio);
return BLK_QC_T_NONE;
}
static int nd_blk_rw_bytes(struct nd_namespace_common *ndns,
......
......@@ -1150,7 +1150,7 @@ static int btt_do_bvec(struct btt *btt, struct bio_integrity_payload *bip,
return ret;
}
static void btt_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t btt_make_request(struct request_queue *q, struct bio *bio)
{
struct bio_integrity_payload *bip = bio_integrity(bio);
struct btt *btt = q->queuedata;
......@@ -1198,6 +1198,7 @@ static void btt_make_request(struct request_queue *q, struct bio *bio)
out:
bio_endio(bio);
return BLK_QC_T_NONE;
}
static int btt_rw_page(struct block_device *bdev, sector_t sector,
......
......@@ -64,7 +64,7 @@ static void pmem_do_bvec(struct pmem_device *pmem, struct page *page,
kunmap_atomic(mem);
}
static void pmem_make_request(struct request_queue *q, struct bio *bio)
static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio)
{
bool do_acct;
unsigned long start;
......@@ -84,6 +84,7 @@ static void pmem_make_request(struct request_queue *q, struct bio *bio)
wmb_pmem();
bio_endio(bio);
return BLK_QC_T_NONE;
}
static int pmem_rw_page(struct block_device *bdev, sector_t sector,
......
......@@ -27,7 +27,8 @@
static int dcssblk_open(struct block_device *bdev, fmode_t mode);
static void dcssblk_release(struct gendisk *disk, fmode_t mode);
static void dcssblk_make_request(struct request_queue *q, struct bio *bio)