Convert from the old request_fn style driver to blk-mq.

Cc: David Miller <davem@davemloft.net>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2018-10-15 08:54:23 -06:00
Родитель ea2c18e104
Коммит fa182a1fa9
1 изменённых файлов: 98 добавлений и 51 удалений

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@ -6,7 +6,7 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/blkdev.h>
#include <linux/blk-mq.h>
#include <linux/hdreg.h>
#include <linux/genhd.h>
#include <linux/cdrom.h>
@ -66,9 +66,10 @@ struct vdc_port {
u64 max_xfer_size;
u32 vdisk_block_size;
u32 drain;
u64 ldc_timeout;
struct timer_list ldc_reset_timer;
struct delayed_work ldc_reset_timer_work;
struct work_struct ldc_reset_work;
/* The server fills these in for us in the disk attribute
@ -80,12 +81,14 @@ struct vdc_port {
u8 vdisk_mtype;
u32 vdisk_phys_blksz;
struct blk_mq_tag_set tag_set;
char disk_name[32];
};
static void vdc_ldc_reset(struct vdc_port *port);
static void vdc_ldc_reset_work(struct work_struct *work);
static void vdc_ldc_reset_timer(struct timer_list *t);
static void vdc_ldc_reset_timer_work(struct work_struct *work);
static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
{
@ -175,11 +178,8 @@ static void vdc_blk_queue_start(struct vdc_port *port)
* handshake completes, so check for initial handshake before we've
* allocated a disk.
*/
if (port->disk && blk_queue_stopped(port->disk->queue) &&
vdc_tx_dring_avail(dr) * 100 / VDC_TX_RING_SIZE >= 50) {
blk_start_queue(port->disk->queue);
}
if (port->disk && vdc_tx_dring_avail(dr) * 100 / VDC_TX_RING_SIZE >= 50)
blk_mq_start_hw_queues(port->disk->queue);
}
static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
@ -197,7 +197,7 @@ static void vdc_handshake_complete(struct vio_driver_state *vio)
{
struct vdc_port *port = to_vdc_port(vio);
del_timer(&port->ldc_reset_timer);
cancel_delayed_work(&port->ldc_reset_timer_work);
vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
vdc_blk_queue_start(port);
}
@ -320,7 +320,7 @@ static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
rqe->req = NULL;
__blk_end_request(req, (desc->status ? BLK_STS_IOERR : 0), desc->size);
blk_mq_end_request(req, desc->status ? BLK_STS_IOERR : 0);
vdc_blk_queue_start(port);
}
@ -525,29 +525,40 @@ static int __send_request(struct request *req)
return err;
}
static void do_vdc_request(struct request_queue *rq)
static blk_status_t vdc_queue_rq(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *bd)
{
struct request *req;
while ((req = blk_peek_request(rq)) != NULL) {
struct vdc_port *port;
struct vdc_port *port = hctx->queue->queuedata;
struct vio_dring_state *dr;
unsigned long flags;
port = req->rq_disk->private_data;
dr = &port->vio.drings[VIO_DRIVER_TX_RING];
if (unlikely(vdc_tx_dring_avail(dr) < 1))
goto wait;
blk_start_request(req);
blk_mq_start_request(bd->rq);
if (__send_request(req) < 0) {
blk_requeue_request(rq, req);
wait:
/* Avoid pointless unplugs. */
blk_stop_queue(rq);
break;
spin_lock_irqsave(&port->vio.lock, flags);
/*
* Doing drain, just end the request in error
*/
if (unlikely(port->drain)) {
spin_unlock_irqrestore(&port->vio.lock, flags);
return BLK_STS_IOERR;
}
if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
spin_unlock_irqrestore(&port->vio.lock, flags);
blk_mq_stop_hw_queue(hctx);
return BLK_STS_DEV_RESOURCE;
}
if (__send_request(bd->rq) < 0) {
spin_unlock_irqrestore(&port->vio.lock, flags);
return BLK_STS_IOERR;
}
spin_unlock_irqrestore(&port->vio.lock, flags);
return BLK_STS_OK;
}
static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
@ -759,6 +770,32 @@ static void vdc_port_down(struct vdc_port *port)
vio_ldc_free(&port->vio);
}
static const struct blk_mq_ops vdc_mq_ops = {
.queue_rq = vdc_queue_rq,
};
static void cleanup_queue(struct request_queue *q)
{
struct vdc_port *port = q->queuedata;
blk_cleanup_queue(q);
blk_mq_free_tag_set(&port->tag_set);
}
static struct request_queue *init_queue(struct vdc_port *port)
{
struct request_queue *q;
int ret;
q = blk_mq_init_sq_queue(&port->tag_set, &vdc_mq_ops, VDC_TX_RING_SIZE,
BLK_MQ_F_SHOULD_MERGE);
if (IS_ERR(q))
return q;
q->queuedata = port;
return q;
}
static int probe_disk(struct vdc_port *port)
{
struct request_queue *q;
@ -796,17 +833,17 @@ static int probe_disk(struct vdc_port *port)
(u64)geom.num_sec);
}
q = blk_init_queue(do_vdc_request, &port->vio.lock);
if (!q) {
q = init_queue(port);
if (IS_ERR(q)) {
printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
port->vio.name);
return -ENOMEM;
return PTR_ERR(q);
}
g = alloc_disk(1 << PARTITION_SHIFT);
if (!g) {
printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
port->vio.name);
blk_cleanup_queue(q);
cleanup_queue(q);
return -ENOMEM;
}
@ -981,7 +1018,7 @@ static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
*/
ldc_timeout = mdesc_get_property(hp, vdev->mp, "vdc-timeout", NULL);
port->ldc_timeout = ldc_timeout ? *ldc_timeout : 0;
timer_setup(&port->ldc_reset_timer, vdc_ldc_reset_timer, 0);
INIT_DELAYED_WORK(&port->ldc_reset_timer_work, vdc_ldc_reset_timer_work);
INIT_WORK(&port->ldc_reset_work, vdc_ldc_reset_work);
err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
@ -1034,18 +1071,14 @@ static int vdc_port_remove(struct vio_dev *vdev)
struct vdc_port *port = dev_get_drvdata(&vdev->dev);
if (port) {
unsigned long flags;
spin_lock_irqsave(&port->vio.lock, flags);
blk_stop_queue(port->disk->queue);
spin_unlock_irqrestore(&port->vio.lock, flags);
blk_mq_stop_hw_queues(port->disk->queue);
flush_work(&port->ldc_reset_work);
del_timer_sync(&port->ldc_reset_timer);
cancel_delayed_work_sync(&port->ldc_reset_timer_work);
del_timer_sync(&port->vio.timer);
del_gendisk(port->disk);
blk_cleanup_queue(port->disk->queue);
cleanup_queue(port->disk->queue);
put_disk(port->disk);
port->disk = NULL;
@ -1080,32 +1113,46 @@ static void vdc_requeue_inflight(struct vdc_port *port)
}
rqe->req = NULL;
blk_requeue_request(port->disk->queue, req);
blk_mq_requeue_request(req, false);
}
}
static void vdc_queue_drain(struct vdc_port *port)
{
struct request *req;
struct request_queue *q = port->disk->queue;
while ((req = blk_fetch_request(port->disk->queue)) != NULL)
__blk_end_request_all(req, BLK_STS_IOERR);
/*
* Mark the queue as draining, then freeze/quiesce to ensure
* that all existing requests are seen in ->queue_rq() and killed
*/
port->drain = 1;
spin_unlock_irq(&port->vio.lock);
blk_mq_freeze_queue(q);
blk_mq_quiesce_queue(q);
spin_lock_irq(&port->vio.lock);
port->drain = 0;
blk_mq_unquiesce_queue(q);
blk_mq_unfreeze_queue(q);
}
static void vdc_ldc_reset_timer(struct timer_list *t)
static void vdc_ldc_reset_timer_work(struct work_struct *work)
{
struct vdc_port *port = from_timer(port, t, ldc_reset_timer);
struct vio_driver_state *vio = &port->vio;
unsigned long flags;
struct vdc_port *port;
struct vio_driver_state *vio;
spin_lock_irqsave(&vio->lock, flags);
port = container_of(work, struct vdc_port, ldc_reset_timer_work.work);
vio = &port->vio;
spin_lock_irq(&vio->lock);
if (!(port->vio.hs_state & VIO_HS_COMPLETE)) {
pr_warn(PFX "%s ldc down %llu seconds, draining queue\n",
port->disk_name, port->ldc_timeout);
vdc_queue_drain(port);
vdc_blk_queue_start(port);
}
spin_unlock_irqrestore(&vio->lock, flags);
spin_unlock_irq(&vio->lock);
}
static void vdc_ldc_reset_work(struct work_struct *work)
@ -1129,7 +1176,7 @@ static void vdc_ldc_reset(struct vdc_port *port)
assert_spin_locked(&port->vio.lock);
pr_warn(PFX "%s ldc link reset\n", port->disk_name);
blk_stop_queue(port->disk->queue);
blk_mq_stop_hw_queues(port->disk->queue);
vdc_requeue_inflight(port);
vdc_port_down(port);
@ -1146,7 +1193,7 @@ static void vdc_ldc_reset(struct vdc_port *port)
}
if (port->ldc_timeout)
mod_timer(&port->ldc_reset_timer,
mod_delayed_work(system_wq, &port->ldc_reset_timer_work,
round_jiffies(jiffies + HZ * port->ldc_timeout));
mod_timer(&port->vio.timer, round_jiffies(jiffies + HZ));
return;