static void __ide_requeue_and_plug(struct request_queue *q, struct request *rq)
{
if (rq)
blk_requeue_request(q, rq);
if (rq || blk_peek_request(q)) {
/* Use 3ms as that was the old plug delay */
blk_delay_queue(q, 3);
}
}
/*
* q->request_fn for old request-based dm.
* Called with the queue lock held.
*/
static void dm_old_request_fn(struct request_queue *q)
{
struct mapped_device *md = q->queuedata;
struct dm_target *ti = md->immutable_target;
struct request *rq;
struct dm_rq_target_io *tio;
sector_t pos = 0;
if (unlikely(!ti)) {
int srcu_idx;
struct dm_table *map = dm_get_live_table(md, &srcu_idx);
if (unlikely(!map)) {
dm_put_live_table(md, srcu_idx);
return;
}
ti = dm_table_find_target(map, pos);
dm_put_live_table(md, srcu_idx);
}
/*
* For suspend, check blk_queue_stopped() and increment
* ->pending within a single queue_lock not to increment the
* number of in-flight I/Os after the queue is stopped in
* dm_suspend().
*/
while (!blk_queue_stopped(q)) {
rq = blk_peek_request(q);
if (!rq)
return;
/* always use block 0 to find the target for flushes for now */
pos = 0;
if (req_op(rq) != REQ_OP_FLUSH)
pos = blk_rq_pos(rq);
if ((dm_old_request_peeked_before_merge_deadline(md) &&
md_in_flight(md) && rq->bio && !bio_multiple_segments(rq->bio) &&
md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) ||
(ti->type->busy && ti->type->busy(ti))) {
blk_delay_queue(q, 10);
return;
}
dm_start_request(md, rq);
tio = tio_from_request(rq);
init_tio(tio, rq, md);
/* Establish tio->ti before queuing work (map_tio_request) */
tio->ti = ti;
kthread_queue_work(&md->kworker, &tio->work);
BUG_ON(!irqs_disabled());
}
}
/* Get the next read/write request; ending requests that we don't handle */
struct request *ace_get_next_request(struct request_queue * q)
{
struct request *req;
while ((req = blk_peek_request(q)) != NULL) {
if (req->cmd_type == REQ_TYPE_FS)
break;
blk_start_request(req);
__blk_end_request_all(req, -EIO);
}
return req;
}
/* Get the next read/write request; ending requests that we don't handle */
struct request *ace_get_next_request(struct request_queue * q)
{
struct request *req;
while ((req = blk_peek_request(q)) != NULL) {
if (blk_fs_request(req))
break;
blk_start_request(req);
__blk_end_request_all(req, -EIO);
}
return req;
}
/*
*****************************************************************************
* READ/WRITE REQUESTS
*****************************************************************************
*/
static void skd_fail_all_pending(struct skd_device *skdev)
{
struct request_queue *q = skdev->queue;
struct request *req;
for (;; ) {
req = blk_peek_request(q);
if (req == NULL)
break;
blk_start_request(req);
__blk_end_request_all(req, -EIO);
}
}
/*
* do_blkif_request
* read a block; request is in a request queue
*/
static void do_blkif_request(struct request_queue *rq)
{
struct blkfront_info *info = NULL;
struct request *req;
int queued;
pr_debug("Entered do_blkif_request\n");
queued = 0;
while ((req = blk_peek_request(rq)) != NULL) {
info = req->rq_disk->private_data;
if (RING_FULL(&info->ring))
goto wait;
blk_start_request(req);
if (!blk_fs_request(req)) {
__blk_end_request_all(req, -EIO);
continue;
}
pr_debug("do_blk_req %p: cmd %p, sec %lx, "
"(%u/%u) buffer:%p [%s]\n",
req, req->cmd, (unsigned long)blk_rq_pos(req),
blk_rq_cur_sectors(req), blk_rq_sectors(req),
req->buffer, rq_data_dir(req) ? "write" : "read");
if (blkif_queue_request(req)) {
blk_requeue_request(rq, req);
wait:
/* Avoid pointless unplugs. */
blk_stop_queue(rq);
break;
}
queued++;
}
if (queued != 0)
flush_requests(info);
}
void
aoedev_downdev(struct aoedev *d)
{
struct aoetgt *t, **tt, **te;
struct list_head *head, *pos, *nx;
struct request *rq;
int i;
d->flags &= ~DEVFL_UP;
/* clean out active and to-be-retransmitted buffers */
for (i = 0; i < NFACTIVE; i++) {
head = &d->factive[i];
list_for_each_safe(pos, nx, head)
downdev_frame(pos);
}
head = &d->rexmitq;
list_for_each_safe(pos, nx, head)
downdev_frame(pos);
/* reset window dressings */
tt = d->targets;
te = tt + d->ntargets;
for (; tt < te && (t = *tt); tt++) {
aoecmd_wreset(t);
t->nout = 0;
}
/* clean out the in-process request (if any) */
aoe_failip(d);
/* fast fail all pending I/O */
if (d->blkq) {
while ((rq = blk_peek_request(d->blkq))) {
blk_start_request(rq);
aoe_end_request(d, rq, 1);
}
}
if (d->gd)
set_capacity(d->gd, 0);
}
static void
aoeblk_request(struct request_queue *q)
{
struct aoedev *d;
struct request *rq;
d = q->queuedata;
if ((d->flags & DEVFL_UP) == 0) {
printk(KERN_INFO "aoe: device %ld.%d is not up\n",
d->aoemajor, d->aoeminor);
while ((rq = blk_peek_request(q))) {
blk_start_request(rq);
aoe_end_request(d, rq, 1);
}
return;
}
aoecmd_work(d);
return;
}
/*
* The simple form of the request function.
*/
static void sbull_request(struct request_queue *q)
{
struct request *req;
while ((req = blk_peek_request(q)) != NULL) {
struct sbull_dev *dev = req->rq_disk->private_data;
blk_start_request(req);
if (! req->cmd_type != REQ_TYPE_FS) {
printk (KERN_NOTICE "Skip non-fs request\n");
__blk_end_request_all(req, -EIO);
continue;
}
// printk (KERN_NOTICE "Req dev %d dir %ld sec %ld, nr %d f %lx\n",
// dev - Devices, rq_data_dir(req),
// req->sector, req->current_nr_sectors,
// req->flags);
sbull_transfer(dev, blk_rq_pos(req), blk_rq_cur_bytes(req),
req->buffer, rq_data_dir(req));
__blk_end_request_all(req, 0);
}
}
static void skd_request_fn(struct request_queue *q)
{
struct skd_device *skdev = q->queuedata;
struct skd_fitmsg_context *skmsg = NULL;
struct fit_msg_hdr *fmh = NULL;
struct skd_request_context *skreq;
struct request *req = NULL;
struct skd_scsi_request *scsi_req;
struct page *page;
unsigned long io_flags;
int error;
u32 lba;
u32 count;
int data_dir;
u32 be_lba;
u32 be_count;
u64 be_dmaa;
u64 cmdctxt;
u32 timo_slot;
void *cmd_ptr;
int flush, fua;
if (skdev->state != SKD_DRVR_STATE_ONLINE) {
skd_request_fn_not_online(q);
return;
}
if (blk_queue_stopped(skdev->queue)) {
if (skdev->skmsg_free_list == NULL ||
skdev->skreq_free_list == NULL ||
skdev->in_flight >= skdev->queue_low_water_mark)
/* There is still some kind of shortage */
return;
queue_flag_clear(QUEUE_FLAG_STOPPED, skdev->queue);
}
/*
* Stop conditions:
* - There are no more native requests
* - There are already the maximum number of requests in progress
* - There are no more skd_request_context entries
* - There are no more FIT msg buffers
*/
for (;; ) {
flush = fua = 0;
req = blk_peek_request(q);
/* Are there any native requests to start? */
if (req == NULL)
break;
lba = (u32)blk_rq_pos(req);
count = blk_rq_sectors(req);
data_dir = rq_data_dir(req);
io_flags = req->cmd_flags;
if (io_flags & REQ_FLUSH)
flush++;
if (io_flags & REQ_FUA)
fua++;
pr_debug("%s:%s:%d new req=%p lba=%u(0x%x) "
"count=%u(0x%x) dir=%d\n",
skdev->name, __func__, __LINE__,
req, lba, lba, count, count, data_dir);
/* At this point we know there is a request */
/* Are too many requets already in progress? */
if (skdev->in_flight >= skdev->cur_max_queue_depth) {
pr_debug("%s:%s:%d qdepth %d, limit %d\n",
skdev->name, __func__, __LINE__,
skdev->in_flight, skdev->cur_max_queue_depth);
break;
}
/* Is a skd_request_context available? */
skreq = skdev->skreq_free_list;
if (skreq == NULL) {
pr_debug("%s:%s:%d Out of req=%p\n",
skdev->name, __func__, __LINE__, q);
break;
}
SKD_ASSERT(skreq->state == SKD_REQ_STATE_IDLE);
SKD_ASSERT((skreq->id & SKD_ID_INCR) == 0);
/* Now we check to see if we can get a fit msg */
if (skmsg == NULL) {
if (skdev->skmsg_free_list == NULL) {
pr_debug("%s:%s:%d Out of msg\n",
skdev->name, __func__, __LINE__);
break;
}
}
skreq->flush_cmd = 0;
skreq->n_sg = 0;
skreq->sg_byte_count = 0;
skreq->discard_page = 0;
/*
* OK to now dequeue request from q.
*
* At this point we are comitted to either start or reject
* the native request. Note that skd_request_context is
* available but is still at the head of the free list.
*/
blk_start_request(req);
skreq->req = req;
skreq->fitmsg_id = 0;
/* Either a FIT msg is in progress or we have to start one. */
if (skmsg == NULL) {
/* Are there any FIT msg buffers available? */
skmsg = skdev->skmsg_free_list;
if (skmsg == NULL) {
pr_debug("%s:%s:%d Out of msg skdev=%p\n",
skdev->name, __func__, __LINE__,
skdev);
break;
}
SKD_ASSERT(skmsg->state == SKD_MSG_STATE_IDLE);
SKD_ASSERT((skmsg->id & SKD_ID_INCR) == 0);
skdev->skmsg_free_list = skmsg->next;
skmsg->state = SKD_MSG_STATE_BUSY;
skmsg->id += SKD_ID_INCR;
/* Initialize the FIT msg header */
fmh = (struct fit_msg_hdr *)skmsg->msg_buf;
memset(fmh, 0, sizeof(*fmh));
fmh->protocol_id = FIT_PROTOCOL_ID_SOFIT;
skmsg->length = sizeof(*fmh);
}
skreq->fitmsg_id = skmsg->id;
/*
* Note that a FIT msg may have just been started
* but contains no SoFIT requests yet.
*/
/*
* Transcode the request, checking as we go. The outcome of
* the transcoding is represented by the error variable.
*/
cmd_ptr = &skmsg->msg_buf[skmsg->length];
memset(cmd_ptr, 0, 32);
be_lba = cpu_to_be32(lba);
be_count = cpu_to_be32(count);
be_dmaa = cpu_to_be64((u64)skreq->sksg_dma_address);
cmdctxt = skreq->id + SKD_ID_INCR;
scsi_req = cmd_ptr;
scsi_req->hdr.tag = cmdctxt;
scsi_req->hdr.sg_list_dma_address = be_dmaa;
if (data_dir == READ)
skreq->sg_data_dir = SKD_DATA_DIR_CARD_TO_HOST;
else
skreq->sg_data_dir = SKD_DATA_DIR_HOST_TO_CARD;
if (io_flags & REQ_DISCARD) {
page = alloc_page(GFP_ATOMIC | __GFP_ZERO);
if (!page) {
pr_err("request_fn:Page allocation failed.\n");
skd_end_request(skdev, skreq, -ENOMEM);
break;
}
skreq->discard_page = 1;
req->completion_data = page;
skd_prep_discard_cdb(scsi_req, skreq, page, lba, count);
} else if (flush == SKD_FLUSH_ZERO_SIZE_FIRST) {
skd_prep_zerosize_flush_cdb(scsi_req, skreq);
SKD_ASSERT(skreq->flush_cmd == 1);
} else {
skd_prep_rw_cdb(scsi_req, data_dir, lba, count);
}
if (fua)
scsi_req->cdb[1] |= SKD_FUA_NV;
if (!req->bio)
goto skip_sg;
error = skd_preop_sg_list(skdev, skreq);
if (error != 0) {
/*
* Complete the native request with error.
* Note that the request context is still at the
* head of the free list, and that the SoFIT request
* was encoded into the FIT msg buffer but the FIT
* msg length has not been updated. In short, the
* only resource that has been allocated but might
* not be used is that the FIT msg could be empty.
*/
pr_debug("%s:%s:%d error Out\n",
skdev->name, __func__, __LINE__);
skd_end_request(skdev, skreq, error);
continue;
}
skip_sg:
scsi_req->hdr.sg_list_len_bytes =
cpu_to_be32(skreq->sg_byte_count);
/* Complete resource allocations. */
skdev->skreq_free_list = skreq->next;
skreq->state = SKD_REQ_STATE_BUSY;
skreq->id += SKD_ID_INCR;
skmsg->length += sizeof(struct skd_scsi_request);
fmh->num_protocol_cmds_coalesced++;
/*
* Update the active request counts.
* Capture the timeout timestamp.
*/
skreq->timeout_stamp = skdev->timeout_stamp;
timo_slot = skreq->timeout_stamp & SKD_TIMEOUT_SLOT_MASK;
skdev->timeout_slot[timo_slot]++;
skdev->in_flight++;
pr_debug("%s:%s:%d req=0x%x busy=%d\n",
skdev->name, __func__, __LINE__,
skreq->id, skdev->in_flight);
/*
* If the FIT msg buffer is full send it.
*/
if (skmsg->length >= SKD_N_FITMSG_BYTES ||
fmh->num_protocol_cmds_coalesced >= skd_max_req_per_msg) {
skd_send_fitmsg(skdev, skmsg);
skmsg = NULL;
fmh = NULL;
}
}
/*
* Is a FIT msg in progress? If it is empty put the buffer back
* on the free list. If it is non-empty send what we got.
* This minimizes latency when there are fewer requests than
* what fits in a FIT msg.
*/
if (skmsg != NULL) {
/* Bigger than just a FIT msg header? */
if (skmsg->length > sizeof(struct fit_msg_hdr)) {
pr_debug("%s:%s:%d sending msg=%p, len %d\n",
skdev->name, __func__, __LINE__,
skmsg, skmsg->length);
skd_send_fitmsg(skdev, skmsg);
} else {
/*
* The FIT msg is empty. It means we got started
* on the msg, but the requests were rejected.
*/
skmsg->state = SKD_MSG_STATE_IDLE;
skmsg->id += SKD_ID_INCR;
skmsg->next = skdev->skmsg_free_list;
skdev->skmsg_free_list = skmsg;
}
skmsg = NULL;
fmh = NULL;
}
/*
* If req is non-NULL it means there is something to do but
* we are out of a resource.
*/
if (req)
blk_stop_queue(skdev->queue);
}
