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-rw-r--r--block/as-iosched.c144
-rw-r--r--block/cfq-iosched.c16
-rw-r--r--block/deadline-iosched.c8
-rw-r--r--block/elevator.c86
-rw-r--r--block/ll_rw_blk.c536
-rw-r--r--block/scsi_ioctl.c2
6 files changed, 424 insertions, 368 deletions
diff --git a/block/as-iosched.c b/block/as-iosched.c
index 43fa204..8da3cf6 100644
--- a/block/as-iosched.c
+++ b/block/as-iosched.c
@@ -182,6 +182,9 @@ struct as_rq {
static kmem_cache_t *arq_pool;
+static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq);
+static void as_antic_stop(struct as_data *ad);
+
/*
* IO Context helper functions
*/
@@ -370,7 +373,7 @@ static struct as_rq *as_find_first_arq(struct as_data *ad, int data_dir)
* existing request against the same sector), which can happen when using
* direct IO, then return the alias.
*/
-static struct as_rq *as_add_arq_rb(struct as_data *ad, struct as_rq *arq)
+static struct as_rq *__as_add_arq_rb(struct as_data *ad, struct as_rq *arq)
{
struct rb_node **p = &ARQ_RB_ROOT(ad, arq)->rb_node;
struct rb_node *parent = NULL;
@@ -397,6 +400,16 @@ static struct as_rq *as_add_arq_rb(struct as_data *ad, struct as_rq *arq)
return NULL;
}
+static void as_add_arq_rb(struct as_data *ad, struct as_rq *arq)
+{
+ struct as_rq *alias;
+
+ while ((unlikely(alias = __as_add_arq_rb(ad, arq)))) {
+ as_move_to_dispatch(ad, alias);
+ as_antic_stop(ad);
+ }
+}
+
static inline void as_del_arq_rb(struct as_data *ad, struct as_rq *arq)
{
if (!ON_RB(&arq->rb_node)) {
@@ -1133,23 +1146,6 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
/*
* take it off the sort and fifo list, add to dispatch queue
*/
- while (!list_empty(&rq->queuelist)) {
- struct request *__rq = list_entry_rq(rq->queuelist.next);
- struct as_rq *__arq = RQ_DATA(__rq);
-
- list_del(&__rq->queuelist);
-
- elv_dispatch_add_tail(ad->q, __rq);
-
- if (__arq->io_context && __arq->io_context->aic)
- atomic_inc(&__arq->io_context->aic->nr_dispatched);
-
- WARN_ON(__arq->state != AS_RQ_QUEUED);
- __arq->state = AS_RQ_DISPATCHED;
-
- ad->nr_dispatched++;
- }
-
as_remove_queued_request(ad->q, rq);
WARN_ON(arq->state != AS_RQ_QUEUED);
@@ -1326,49 +1322,12 @@ fifo_expired:
}
/*
- * Add arq to a list behind alias
- */
-static inline void
-as_add_aliased_request(struct as_data *ad, struct as_rq *arq,
- struct as_rq *alias)
-{
- struct request *req = arq->request;
- struct list_head *insert = alias->request->queuelist.prev;
-
- /*
- * Transfer list of aliases
- */
- while (!list_empty(&req->queuelist)) {
- struct request *__rq = list_entry_rq(req->queuelist.next);
- struct as_rq *__arq = RQ_DATA(__rq);
-
- list_move_tail(&__rq->queuelist, &alias->request->queuelist);
-
- WARN_ON(__arq->state != AS_RQ_QUEUED);
- }
-
- /*
- * Another request with the same start sector on the rbtree.
- * Link this request to that sector. They are untangled in
- * as_move_to_dispatch
- */
- list_add(&arq->request->queuelist, insert);
-
- /*
- * Don't want to have to handle merges.
- */
- as_del_arq_hash(arq);
- arq->request->flags |= REQ_NOMERGE;
-}
-
-/*
* add arq to rbtree and fifo
*/
static void as_add_request(request_queue_t *q, struct request *rq)
{
struct as_data *ad = q->elevator->elevator_data;
struct as_rq *arq = RQ_DATA(rq);
- struct as_rq *alias;
int data_dir;
arq->state = AS_RQ_NEW;
@@ -1387,33 +1346,17 @@ static void as_add_request(request_queue_t *q, struct request *rq)
atomic_inc(&arq->io_context->aic->nr_queued);
}
- alias = as_add_arq_rb(ad, arq);
- if (!alias) {
- /*
- * set expire time (only used for reads) and add to fifo list
- */
- arq->expires = jiffies + ad->fifo_expire[data_dir];
- list_add_tail(&arq->fifo, &ad->fifo_list[data_dir]);
+ as_add_arq_rb(ad, arq);
+ if (rq_mergeable(arq->request))
+ as_add_arq_hash(ad, arq);
- if (rq_mergeable(arq->request))
- as_add_arq_hash(ad, arq);
- as_update_arq(ad, arq); /* keep state machine up to date */
-
- } else {
- as_add_aliased_request(ad, arq, alias);
-
- /*
- * have we been anticipating this request?
- * or does it come from the same process as the one we are
- * anticipating for?
- */
- if (ad->antic_status == ANTIC_WAIT_REQ
- || ad->antic_status == ANTIC_WAIT_NEXT) {
- if (as_can_break_anticipation(ad, arq))
- as_antic_stop(ad);
- }
- }
+ /*
+ * set expire time (only used for reads) and add to fifo list
+ */
+ arq->expires = jiffies + ad->fifo_expire[data_dir];
+ list_add_tail(&arq->fifo, &ad->fifo_list[data_dir]);
+ as_update_arq(ad, arq); /* keep state machine up to date */
arq->state = AS_RQ_QUEUED;
}
@@ -1536,23 +1479,8 @@ static void as_merged_request(request_queue_t *q, struct request *req)
* if the merge was a front merge, we need to reposition request
*/
if (rq_rb_key(req) != arq->rb_key) {
- struct as_rq *alias, *next_arq = NULL;
-
- if (ad->next_arq[arq->is_sync] == arq)
- next_arq = as_find_next_arq(ad, arq);
-
- /*
- * Note! We should really be moving any old aliased requests
- * off this request and try to insert them into the rbtree. We
- * currently don't bother. Ditto the next function.
- */
as_del_arq_rb(ad, arq);
- if ((alias = as_add_arq_rb(ad, arq))) {
- list_del_init(&arq->fifo);
- as_add_aliased_request(ad, arq, alias);
- if (next_arq)
- ad->next_arq[arq->is_sync] = next_arq;
- }
+ as_add_arq_rb(ad, arq);
/*
* Note! At this stage of this and the next function, our next
* request may not be optimal - eg the request may have "grown"
@@ -1579,18 +1507,8 @@ static void as_merged_requests(request_queue_t *q, struct request *req,
as_add_arq_hash(ad, arq);
if (rq_rb_key(req) != arq->rb_key) {
- struct as_rq *alias, *next_arq = NULL;
-
- if (ad->next_arq[arq->is_sync] == arq)
- next_arq = as_find_next_arq(ad, arq);
-
as_del_arq_rb(ad, arq);
- if ((alias = as_add_arq_rb(ad, arq))) {
- list_del_init(&arq->fifo);
- as_add_aliased_request(ad, arq, alias);
- if (next_arq)
- ad->next_arq[arq->is_sync] = next_arq;
- }
+ as_add_arq_rb(ad, arq);
}
/*
@@ -1610,18 +1528,6 @@ static void as_merged_requests(request_queue_t *q, struct request *req,
}
/*
- * Transfer list of aliases
- */
- while (!list_empty(&next->queuelist)) {
- struct request *__rq = list_entry_rq(next->queuelist.next);
- struct as_rq *__arq = RQ_DATA(__rq);
-
- list_move_tail(&__rq->queuelist, &req->queuelist);
-
- WARN_ON(__arq->state != AS_RQ_QUEUED);
- }
-
- /*
* kill knowledge of next, this one is a goner
*/
as_remove_queued_request(q, next);
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index ee0bb41..74fae2d 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -25,15 +25,15 @@
/*
* tunables
*/
-static int cfq_quantum = 4; /* max queue in one round of service */
-static int cfq_queued = 8; /* minimum rq allocate limit per-queue*/
-static int cfq_fifo_expire[2] = { HZ / 4, HZ / 8 };
-static int cfq_back_max = 16 * 1024; /* maximum backwards seek, in KiB */
-static int cfq_back_penalty = 2; /* penalty of a backwards seek */
+static const int cfq_quantum = 4; /* max queue in one round of service */
+static const int cfq_queued = 8; /* minimum rq allocate limit per-queue*/
+static const int cfq_fifo_expire[2] = { HZ / 4, HZ / 8 };
+static const int cfq_back_max = 16 * 1024; /* maximum backwards seek, in KiB */
+static const int cfq_back_penalty = 2; /* penalty of a backwards seek */
-static int cfq_slice_sync = HZ / 10;
+static const int cfq_slice_sync = HZ / 10;
static int cfq_slice_async = HZ / 25;
-static int cfq_slice_async_rq = 2;
+static const int cfq_slice_async_rq = 2;
static int cfq_slice_idle = HZ / 100;
#define CFQ_IDLE_GRACE (HZ / 10)
@@ -45,7 +45,7 @@ static int cfq_slice_idle = HZ / 100;
/*
* disable queueing at the driver/hardware level
*/
-static int cfq_max_depth = 2;
+static const int cfq_max_depth = 2;
/*
* for the hash of cfqq inside the cfqd
diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c
index 9cbec09..27e494b 100644
--- a/block/deadline-iosched.c
+++ b/block/deadline-iosched.c
@@ -19,10 +19,10 @@
/*
* See Documentation/block/deadline-iosched.txt
*/
-static int read_expire = HZ / 2; /* max time before a read is submitted. */
-static int write_expire = 5 * HZ; /* ditto for writes, these limits are SOFT! */
-static int writes_starved = 2; /* max times reads can starve a write */
-static int fifo_batch = 16; /* # of sequential requests treated as one
+static const int read_expire = HZ / 2; /* max time before a read is submitted. */
+static const int write_expire = 5 * HZ; /* ditto for writes, these limits are SOFT! */
+static const int writes_starved = 2; /* max times reads can starve a write */
+static const int fifo_batch = 16; /* # of sequential requests treated as one
by the above parameters. For throughput. */
static const int deadline_hash_shift = 5;
diff --git a/block/elevator.c b/block/elevator.c
index 6c3fc8a..39dcccc 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -304,15 +304,7 @@ void elv_requeue_request(request_queue_t *q, struct request *rq)
rq->flags &= ~REQ_STARTED;
- /*
- * if this is the flush, requeue the original instead and drop the flush
- */
- if (rq->flags & REQ_BAR_FLUSH) {
- clear_bit(QUEUE_FLAG_FLUSH, &q->queue_flags);
- rq = rq->end_io_data;
- }
-
- __elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 0);
+ __elv_add_request(q, rq, ELEVATOR_INSERT_REQUEUE, 0);
}
static void elv_drain_elevator(request_queue_t *q)
@@ -332,8 +324,19 @@ static void elv_drain_elevator(request_queue_t *q)
void __elv_add_request(request_queue_t *q, struct request *rq, int where,
int plug)
{
+ struct list_head *pos;
+ unsigned ordseq;
+
+ if (q->ordcolor)
+ rq->flags |= REQ_ORDERED_COLOR;
+
if (rq->flags & (REQ_SOFTBARRIER | REQ_HARDBARRIER)) {
/*
+ * toggle ordered color
+ */
+ q->ordcolor ^= 1;
+
+ /*
* barriers implicitly indicate back insertion
*/
if (where == ELEVATOR_INSERT_SORT)
@@ -393,6 +396,30 @@ void __elv_add_request(request_queue_t *q, struct request *rq, int where,
q->elevator->ops->elevator_add_req_fn(q, rq);
break;
+ case ELEVATOR_INSERT_REQUEUE:
+ /*
+ * If ordered flush isn't in progress, we do front
+ * insertion; otherwise, requests should be requeued
+ * in ordseq order.
+ */
+ rq->flags |= REQ_SOFTBARRIER;
+
+ if (q->ordseq == 0) {
+ list_add(&rq->queuelist, &q->queue_head);
+ break;
+ }
+
+ ordseq = blk_ordered_req_seq(rq);
+
+ list_for_each(pos, &q->queue_head) {
+ struct request *pos_rq = list_entry_rq(pos);
+ if (ordseq <= blk_ordered_req_seq(pos_rq))
+ break;
+ }
+
+ list_add_tail(&rq->queuelist, pos);
+ break;
+
default:
printk(KERN_ERR "%s: bad insertion point %d\n",
__FUNCTION__, where);
@@ -422,25 +449,16 @@ static inline struct request *__elv_next_request(request_queue_t *q)
{
struct request *rq;
- if (unlikely(list_empty(&q->queue_head) &&
- !q->elevator->ops->elevator_dispatch_fn(q, 0)))
- return NULL;
-
- rq = list_entry_rq(q->queue_head.next);
-
- /*
- * if this is a barrier write and the device has to issue a
- * flush sequence to support it, check how far we are
- */
- if (blk_fs_request(rq) && blk_barrier_rq(rq)) {
- BUG_ON(q->ordered == QUEUE_ORDERED_NONE);
+ while (1) {
+ while (!list_empty(&q->queue_head)) {
+ rq = list_entry_rq(q->queue_head.next);
+ if (blk_do_ordered(q, &rq))
+ return rq;
+ }
- if (q->ordered == QUEUE_ORDERED_FLUSH &&
- !blk_barrier_preflush(rq))
- rq = blk_start_pre_flush(q, rq);
+ if (!q->elevator->ops->elevator_dispatch_fn(q, 0))
+ return NULL;
}
-
- return rq;
}
struct request *elv_next_request(request_queue_t *q)
@@ -498,7 +516,7 @@ struct request *elv_next_request(request_queue_t *q)
blkdev_dequeue_request(rq);
rq->flags |= REQ_QUIET;
end_that_request_chunk(rq, 0, nr_bytes);
- end_that_request_last(rq);
+ end_that_request_last(rq, 0);
} else {
printk(KERN_ERR "%s: bad return=%d\n", __FUNCTION__,
ret);
@@ -593,7 +611,21 @@ void elv_completed_request(request_queue_t *q, struct request *rq)
* request is released from the driver, io must be done
*/
if (blk_account_rq(rq)) {
+ struct request *first_rq = list_entry_rq(q->queue_head.next);
+
q->in_flight--;
+
+ /*
+ * Check if the queue is waiting for fs requests to be
+ * drained for flush sequence.
+ */
+ if (q->ordseq && q->in_flight == 0 &&
+ blk_ordered_cur_seq(q) == QUEUE_ORDSEQ_DRAIN &&
+ blk_ordered_req_seq(first_rq) > QUEUE_ORDSEQ_DRAIN) {
+ blk_ordered_complete_seq(q, QUEUE_ORDSEQ_DRAIN, 0);
+ q->request_fn(q);
+ }
+
if (blk_sorted_rq(rq) && e->ops->elevator_completed_req_fn)
e->ops->elevator_completed_req_fn(q, rq);
}
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index d4beb9a..91d3b48 100644
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -36,6 +36,8 @@
static void blk_unplug_work(void *data);
static void blk_unplug_timeout(unsigned long data);
static void drive_stat_acct(struct request *rq, int nr_sectors, int new_io);
+static void init_request_from_bio(struct request *req, struct bio *bio);
+static int __make_request(request_queue_t *q, struct bio *bio);
/*
* For the allocated request tables
@@ -288,8 +290,8 @@ static inline void rq_init(request_queue_t *q, struct request *rq)
/**
* blk_queue_ordered - does this queue support ordered writes
- * @q: the request queue
- * @flag: see below
+ * @q: the request queue
+ * @ordered: one of QUEUE_ORDERED_*
*
* Description:
* For journalled file systems, doing ordered writes on a commit
@@ -298,28 +300,30 @@ static inline void rq_init(request_queue_t *q, struct request *rq)
* feature should call this function and indicate so.
*
**/
-void blk_queue_ordered(request_queue_t *q, int flag)
-{
- switch (flag) {
- case QUEUE_ORDERED_NONE:
- if (q->flush_rq)
- kmem_cache_free(request_cachep, q->flush_rq);
- q->flush_rq = NULL;
- q->ordered = flag;
- break;
- case QUEUE_ORDERED_TAG:
- q->ordered = flag;
- break;
- case QUEUE_ORDERED_FLUSH:
- q->ordered = flag;
- if (!q->flush_rq)
- q->flush_rq = kmem_cache_alloc(request_cachep,
- GFP_KERNEL);
- break;
- default:
- printk("blk_queue_ordered: bad value %d\n", flag);
- break;
+int blk_queue_ordered(request_queue_t *q, unsigned ordered,
+ prepare_flush_fn *prepare_flush_fn)
+{
+ if (ordered & (QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_POSTFLUSH) &&
+ prepare_flush_fn == NULL) {
+ printk(KERN_ERR "blk_queue_ordered: prepare_flush_fn required\n");
+ return -EINVAL;
+ }
+
+ if (ordered != QUEUE_ORDERED_NONE &&
+ ordered != QUEUE_ORDERED_DRAIN &&
+ ordered != QUEUE_ORDERED_DRAIN_FLUSH &&
+ ordered != QUEUE_ORDERED_DRAIN_FUA &&
+ ordered != QUEUE_ORDERED_TAG &&
+ ordered != QUEUE_ORDERED_TAG_FLUSH &&
+ ordered != QUEUE_ORDERED_TAG_FUA) {
+ printk(KERN_ERR "blk_queue_ordered: bad value %d\n", ordered);
+ return -EINVAL;
}
+
+ q->next_ordered = ordered;
+ q->prepare_flush_fn = prepare_flush_fn;
+
+ return 0;
}
EXPORT_SYMBOL(blk_queue_ordered);
@@ -344,167 +348,265 @@ EXPORT_SYMBOL(blk_queue_issue_flush_fn);
/*
* Cache flushing for ordered writes handling
*/
-static void blk_pre_flush_end_io(struct request *flush_rq)
+inline unsigned blk_ordered_cur_seq(request_queue_t *q)
{
- struct request *rq = flush_rq->end_io_data;
- request_queue_t *q = rq->q;
-
- elv_completed_request(q, flush_rq);
-
- rq->flags |= REQ_BAR_PREFLUSH;
-
- if (!flush_rq->errors)
- elv_requeue_request(q, rq);
- else {
- q->end_flush_fn(q, flush_rq);
- clear_bit(QUEUE_FLAG_FLUSH, &q->queue_flags);
- q->request_fn(q);
- }
+ if (!q->ordseq)
+ return 0;
+ return 1 << ffz(q->ordseq);
}
-static void blk_post_flush_end_io(struct request *flush_rq)
+unsigned blk_ordered_req_seq(struct request *rq)
{
- struct request *rq = flush_rq->end_io_data;
request_queue_t *q = rq->q;
- elv_completed_request(q, flush_rq);
+ BUG_ON(q->ordseq == 0);
- rq->flags |= REQ_BAR_POSTFLUSH;
+ if (rq == &q->pre_flush_rq)
+ return QUEUE_ORDSEQ_PREFLUSH;
+ if (rq == &q->bar_rq)
+ return QUEUE_ORDSEQ_BAR;
+ if (rq == &q->post_flush_rq)
+ return QUEUE_ORDSEQ_POSTFLUSH;
- q->end_flush_fn(q, flush_rq);
- clear_bit(QUEUE_FLAG_FLUSH, &q->queue_flags);
- q->request_fn(q);
+ if ((rq->flags & REQ_ORDERED_COLOR) ==
+ (q->orig_bar_rq->flags & REQ_ORDERED_COLOR))
+ return QUEUE_ORDSEQ_DRAIN;
+ else
+ return QUEUE_ORDSEQ_DONE;
}
-struct request *blk_start_pre_flush(request_queue_t *q, struct request *rq)
+void blk_ordered_complete_seq(request_queue_t *q, unsigned seq, int error)
{
- struct request *flush_rq = q->flush_rq;
-
- BUG_ON(!blk_barrier_rq(rq));
+ struct request *rq;
+ int uptodate;
- if (test_and_set_bit(QUEUE_FLAG_FLUSH, &q->queue_flags))
- return NULL;
+ if (error && !q->orderr)
+ q->orderr = error;
- rq_init(q, flush_rq);
- flush_rq->elevator_private = NULL;
- flush_rq->flags = REQ_BAR_FLUSH;
- flush_rq->rq_disk = rq->rq_disk;
- flush_rq->rl = NULL;
+ BUG_ON(q->ordseq & seq);
+ q->ordseq |= seq;
- /*
- * prepare_flush returns 0 if no flush is needed, just mark both
- * pre and post flush as done in that case
- */
- if (!q->prepare_flush_fn(q, flush_rq)) {
- rq->flags |= REQ_BAR_PREFLUSH | REQ_BAR_POSTFLUSH;
- clear_bit(QUEUE_FLAG_FLUSH, &q->queue_flags);
- return rq;
- }
+ if (blk_ordered_cur_seq(q) != QUEUE_ORDSEQ_DONE)
+ return;
/*
- * some drivers dequeue requests right away, some only after io
- * completion. make sure the request is dequeued.
+ * Okay, sequence complete.
*/
- if (!list_empty(&rq->queuelist))
- blkdev_dequeue_request(rq);
+ rq = q->orig_bar_rq;
+ uptodate = q->orderr ? q->orderr : 1;
- flush_rq->end_io_data = rq;
- flush_rq->end_io = blk_pre_flush_end_io;
+ q->ordseq = 0;
- __elv_add_request(q, flush_rq, ELEVATOR_INSERT_FRONT, 0);
- return flush_rq;
+ end_that_request_first(rq, uptodate, rq->hard_nr_sectors);
+ end_that_request_last(rq, uptodate);
}
-static void blk_start_post_flush(request_queue_t *q, struct request *rq)
+static void pre_flush_end_io(struct request *rq, int error)
{
- struct request *flush_rq = q->flush_rq;
+ elv_completed_request(rq->q, rq);
+ blk_ordered_complete_seq(rq->q, QUEUE_ORDSEQ_PREFLUSH, error);
+}
- BUG_ON(!blk_barrier_rq(rq));
+static void bar_end_io(struct request *rq, int error)
+{
+ elv_completed_request(rq->q, rq);
+ blk_ordered_complete_seq(rq->q, QUEUE_ORDSEQ_BAR, error);
+}
- rq_init(q, flush_rq);
- flush_rq->elevator_private = NULL;
- flush_rq->flags = REQ_BAR_FLUSH;
- flush_rq->rq_disk = rq->rq_disk;
- flush_rq->rl = NULL;
+static void post_flush_end_io(struct request *rq, int error)
+{
+ elv_completed_request(rq->q, rq);
+ blk_ordered_complete_seq(rq->q, QUEUE_ORDSEQ_POSTFLUSH, error);
+}
- if (q->prepare_flush_fn(q, flush_rq)) {
- flush_rq->end_io_data = rq;
- flush_rq->end_io = blk_post_flush_end_io;
+static void queue_flush(request_queue_t *q, unsigned which)
+{
+ struct request *rq;
+ rq_end_io_fn *end_io;
- __elv_add_request(q, flush_rq, ELEVATOR_INSERT_FRONT, 0);
- q->request_fn(q);
+ if (which == QUEUE_ORDERED_PREFLUSH) {
+ rq = &q->pre_flush_rq;
+ end_io = pre_flush_end_io;
+ } else {
+ rq = &q->post_flush_rq;
+ end_io = post_flush_end_io;
}
+
+ rq_init(q, rq);
+ rq->flags = REQ_HARDBARRIER;
+ rq->elevator_private = NULL;
+ rq->rq_disk = q->bar_rq.rq_disk;
+ rq->rl = NULL;
+ rq->end_io = end_io;
+ q->prepare_flush_fn(q, rq);
+
+ __elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 0);
}
-static inline int blk_check_end_barrier(request_queue_t *q, struct request *rq,
- int sectors)
+static inline struct request *start_ordered(request_queue_t *q,
+ struct request *rq)
{
- if (sectors > rq->nr_sectors)
- sectors = rq->nr_sectors;
+ q->bi_size = 0;
+ q->orderr = 0;
+ q->ordered = q->next_ordered;
+ q->ordseq |= QUEUE_ORDSEQ_STARTED;
+
+ /*
+ * Prep proxy barrier request.
+ */
+ blkdev_dequeue_request(rq);
+ q->orig_bar_rq = rq;
+ rq = &q->bar_rq;
+ rq_init(q, rq);
+ rq->flags = bio_data_dir(q->orig_bar_rq->bio);
+ rq->flags |= q->ordered & QUEUE_ORDERED_FUA ? REQ_FUA : 0;
+ rq->elevator_private = NULL;
+ rq->rl = NULL;
+ init_request_from_bio(rq, q->orig_bar_rq->bio);
+ rq->end_io = bar_end_io;
+
+ /*
+ * Queue ordered sequence. As we stack them at the head, we
+ * need to queue in reverse order. Note that we rely on that
+ * no fs request uses ELEVATOR_INSERT_FRONT and thus no fs
+ * request gets inbetween ordered sequence.
+ */
+ if (q->ordered & QUEUE_ORDERED_POSTFLUSH)
+ queue_flush(q, QUEUE_ORDERED_POSTFLUSH);
+ else
+ q->ordseq |= QUEUE_ORDSEQ_POSTFLUSH;
+
+ __elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 0);
+
+ if (q->ordered & QUEUE_ORDERED_PREFLUSH) {
+ queue_flush(q, QUEUE_ORDERED_PREFLUSH);
+ rq = &q->pre_flush_rq;
+ } else
+ q->ordseq |= QUEUE_ORDSEQ_PREFLUSH;
- rq->nr_sectors -= sectors;
- return rq->nr_sectors;
+ if ((q->ordered & QUEUE_ORDERED_TAG) || q->in_flight == 0)
+ q->ordseq |= QUEUE_ORDSEQ_DRAIN;
+ else
+ rq = NULL;
+
+ return rq;
}
-static int __blk_complete_barrier_rq(request_queue_t *q, struct request *rq,
- int sectors, int queue_locked)
+int blk_do_ordered(request_queue_t *q, struct request **rqp)
{
- if (q->ordered != QUEUE_ORDERED_FLUSH)
- return 0;
- if (!blk_fs_request(rq) || !blk_barrier_rq(rq))
- return 0;
- if (blk_barrier_postflush(rq))
- return 0;
+ struct request *rq = *rqp, *allowed_rq;
+ int is_barrier = blk_fs_request(rq) && blk_barrier_rq(rq);
- if (!blk_check_end_barrier(q, rq, sectors)) {
- unsigned long flags = 0;
+ if (!q->ordseq) {
+ if (!is_barrier)
+ return 1;
- if (!queue_locked)
- spin_lock_irqsave(q->queue_lock, flags);
+ if (q->next_ordered != QUEUE_ORDERED_NONE) {
+ *rqp = start_ordered(q, rq);
+ return 1;
+ } else {
+ /*
+ * This can happen when the queue switches to
+ * ORDERED_NONE while this request is on it.
+ */
+ blkdev_dequeue_request(rq);
+ end_that_request_first(rq, -EOPNOTSUPP,
+ rq->hard_nr_sectors);
+ end_that_request_last(rq, -EOPNOTSUPP);
+ *rqp = NULL;
+ return 0;
+ }
+ }
- blk_start_post_flush(q, rq);
+ if (q->ordered & QUEUE_ORDERED_TAG) {
+ if (is_barrier && rq != &q->bar_rq)
+ *rqp = NULL;
+ return 1;
+ }
- if (!queue_locked)
- spin_unlock_irqrestore(q->queue_lock, flags);
+ switch (blk_ordered_cur_seq(q)) {
+ case QUEUE_ORDSEQ_PREFLUSH:
+ allowed_rq = &q->pre_flush_rq;
+ break;
+ case QUEUE_ORDSEQ_BAR:
+ allowed_rq = &q->bar_rq;
+ break;
+ case QUEUE_ORDSEQ_POSTFLUSH:
+ allowed_rq = &q->post_flush_rq;
+ break;
+ default:
+ allowed_rq = NULL;
+ break;
}
+ if (rq != allowed_rq &&
+ (blk_fs_request(rq) || rq == &q->pre_flush_rq ||
+ rq == &q->post_flush_rq))
+ *rqp = NULL;
+
return 1;
}
-/**
- * blk_complete_barrier_rq - complete possible barrier request
- * @q: the request queue for the device
- * @rq: the request
- * @sectors: number of sectors to complete
- *
- * Description:
- * Used in driver end_io handling to determine whether to postpone
- * completion of a barrier request until a post flush has been done. This
- * is the unlocked variant, used if the caller doesn't already hold the
- * queue lock.
- **/
-int blk_complete_barrier_rq(request_queue_t *q, struct request *rq, int sectors)
+static int flush_dry_bio_endio(struct bio *bio, unsigned int bytes, int error)
{
- return __blk_complete_barrier_rq(q, rq, sectors, 0);
+ request_queue_t *q = bio->bi_private;
+ struct bio_vec *bvec;
+ int i;
+
+ /*
+ * This is dry run, restore bio_sector and size. We'll finish
+ * this request again with the original bi_end_io after an
+ * error occurs or post flush is complete.
+ */
+ q->bi_size += bytes;
+
+ if (bio->bi_size)
+ return 1;
+
+ /* Rewind bvec's */
+ bio->bi_idx = 0;
+ bio_for_each_segment(bvec, bio, i) {
+ bvec->bv_len += bvec->bv_offset;
+ bvec->bv_offset = 0;
+ }
+
+ /* Reset bio */
+ set_bit(BIO_UPTODATE, &bio->bi_flags);
+ bio->bi_size = q->bi_size;
+ bio->bi_sector -= (q->bi_size >> 9);
+ q->bi_size = 0;
+
+ return 0;
}
-EXPORT_SYMBOL(blk_complete_barrier_rq);
-/**
- * blk_complete_barrier_rq_locked - complete possible barrier request
- * @q: the request queue for the device
- * @rq: the request
- * @sectors: number of sectors to complete
- *
- * Description:
- * See blk_complete_barrier_rq(). This variant must be used if the caller
- * holds the queue lock.
- **/
-int blk_complete_barrier_rq_locked(request_queue_t *q, struct request *rq,
- int sectors)
+static inline int ordered_bio_endio(struct request *rq, struct bio *bio,
+ unsigned int nbytes, int error)
{
- return __blk_complete_barrier_rq(q, rq, sectors, 1);
+ request_queue_t *q = rq->q;
+ bio_end_io_t *endio;
+ void *private;
+
+ if (&q->bar_rq != rq)
+ return 0;
+
+ /*
+ * Okay, this is the barrier request in progress, dry finish it.
+ */
+ if (error && !q->orderr)
+ q->orderr = error;
+
+ endio = bio->bi_end_io;
+ private = bio->bi_private;
+ bio->bi_end_io = flush_dry_bio_endio;
+ bio->bi_private = q;
+
+ bio_endio(bio, nbytes, error);
+
+ bio->bi_end_io = endio;
+ bio->bi_private = private;
+
+ return 1;
}
-EXPORT_SYMBOL(blk_complete_barrier_rq_locked);
/**
* blk_queue_bounce_limit - set bounce buffer limit for queue
@@ -1039,12 +1141,13 @@ void blk_queue_invalidate_tags(request_queue_t *q)
EXPORT_SYMBOL(blk_queue_invalidate_tags);
-static char *rq_flags[] = {
+static const char * const rq_flags[] = {
"REQ_RW",
"REQ_FAILFAST",
"REQ_SORTED",
"REQ_SOFTBARRIER",
"REQ_HARDBARRIER",
+ "REQ_FUA",
"REQ_CMD",
"REQ_NOMERGE",
"REQ_STARTED",
@@ -1064,6 +1167,7 @@ static char *rq_flags[] = {
"REQ_PM_SUSPEND",
"REQ_PM_RESUME",
"REQ_PM_SHUTDOWN",
+ "REQ_ORDERED_COLOR",
};
void blk_dump_rq_flags(struct request *rq, char *msg)
@@ -1641,8 +1745,6 @@ void blk_cleanup_queue(request_queue_t * q)
if (q->queue_tags)
__blk_queue_free_tags(q);
- blk_queue_ordered(q, QUEUE_ORDERED_NONE);
-
kmem_cache_free(requestq_cachep, q);
}
@@ -1667,8 +1769,6 @@ static int blk_init_free_list(request_queue_t *q)
return 0;
}
-static int __make_request(request_queue_t *, struct bio *);
-
request_queue_t *blk_alloc_queue(gfp_t gfp_mask)
{
return blk_alloc_queue_node(gfp_mask, -1);
@@ -1908,40 +2008,40 @@ static struct request *get_request(request_queue_t *q, int rw, struct bio *bio,
{
struct request *rq = NULL;
struct request_list *rl = &q->rq;
- struct io_context *ioc = current_io_context(GFP_ATOMIC);
- int priv;
+ struct io_context *ioc = NULL;
+ int may_queue, priv;
- if (rl->count[rw]+1 >= q->nr_requests) {
- /*
- * The queue will fill after this allocation, so set it as
- * full, and mark this process as "batching". This process
- * will be allowed to complete a batch of requests, others
- * will be blocked.
- */
- if (!blk_queue_full(q, rw)) {
- ioc_set_batching(q, ioc);
- blk_set_queue_full(q, rw);
- }
- }
+ may_queue = elv_may_queue(q, rw, bio);
+ if (may_queue == ELV_MQUEUE_NO)
+ goto rq_starved;
- switch (elv_may_queue(q, rw, bio)) {
- case ELV_MQUEUE_NO:
- goto rq_starved;
- case ELV_MQUEUE_MAY:
- break;
- case ELV_MQUEUE_MUST:
- goto get_rq;
- }
-
- if (blk_queue_full(q, rw) && !ioc_batching(q, ioc)) {
- /*
- * The queue is full and the allocating process is not a
- * "batcher", and not exempted by the IO scheduler
- */
- goto out;
+ if (rl->count[rw]+1 >= queue_congestion_on_threshold(q)) {
+ if (rl->count[rw]+1 >= q->nr_requests) {
+ ioc = current_io_context(GFP_ATOMIC);
+ /*
+ * The queue will fill after this allocation, so set
+ * it as full, and mark this process as "batching".
+ * This process will be allowed to complete a batch of
+ * requests, others will be blocked.
+ */
+ if (!blk_queue_full(q, rw)) {
+ ioc_set_batching(q, ioc);
+ blk_set_queue_full(q, rw);
+ } else {
+ if (may_queue != ELV_MQUEUE_MUST
+ && !ioc_batching(q, ioc)) {
+ /*
+ * The queue is full and the allocating
+ * process is not a "batcher", and not
+ * exempted by the IO scheduler
+ */
+ goto out;
+ }
+ }
+ }
+ set_queue_congested(q, rw);
}
-get_rq:
/*
* Only allow batching queuers to allocate up to 50% over the defined
* limit of requests, otherwise we could have thousands of requests
@@ -1952,8 +2052,6 @@ get_rq:
rl->count[rw]++;
rl->starved[rw] = 0;
- if (rl->count[rw] >= queue_congestion_on_threshold(q))
- set_queue_congested(q, rw);
priv = !test_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
if (priv)
@@ -1962,7 +2060,7 @@ get_rq:
spin_unlock_irq(q->queue_lock);
rq = blk_alloc_request(q, rw, bio, priv, gfp_mask);
- if (!rq) {
+ if (unlikely(!rq)) {
/*
* Allocation failed presumably due to memory. Undo anything
* we might have messed up.
@@ -1987,6 +2085,12 @@ rq_starved:
goto out;
}
+ /*
+ * ioc may be NULL here, and ioc_batching will be false. That's
+ * OK, if the queue is under the request limit then requests need
+ * not count toward the nr_batch_requests limit. There will always
+ * be some limit enforced by BLK_BATCH_TIME.
+ */
if (ioc_batching(q, ioc))
ioc->nr_batch_requests--;
@@ -2313,7 +2417,7 @@ EXPORT_SYMBOL(blk_rq_map_kern);
*/
void blk_execute_rq_nowait(request_queue_t *q, struct gendisk *bd_disk,
struct request *rq, int at_head,
- void (*done)(struct request *))
+ rq_end_io_fn *done)
{
int where = at_head ? ELEVATOR_INSERT_FRONT : ELEVATOR_INSERT_BACK;
@@ -2517,7 +2621,7 @@ EXPORT_SYMBOL(blk_put_request);
* blk_end_sync_rq - executes a completion event on a request
* @rq: request to complete
*/
-void blk_end_sync_rq(struct request *rq)
+void blk_end_sync_rq(struct request *rq, int error)
{
struct completion *waiting = rq->waiting;
@@ -2655,6 +2759,36 @@ void blk_attempt_remerge(request_queue_t *q, struct request *rq)
EXPORT_SYMBOL(blk_attempt_remerge);
+static void init_request_from_bio(struct request *req, struct bio *bio)
+{
+ req->flags |= REQ_CMD;
+
+ /*
+ * inherit FAILFAST from bio (for read-ahead, and explicit FAILFAST)
+ */
+ if (bio_rw_ahead(bio) || bio_failfast(bio))
+ req->flags |= REQ_FAILFAST;
+
+ /*
+ * REQ_BARRIER implies no merging, but lets make it explicit
+ */
+ if (unlikely(bio_barrier(bio)))
+ req->flags |= (REQ_HARDBARRIER | REQ_NOMERGE);
+
+ req->errors = 0;
+ req->hard_sector = req->sector = bio->bi_sector;
+ req->hard_nr_sectors = req->nr_sectors = bio_sectors(bio);
+ req->current_nr_sectors = req->hard_cur_sectors = bio_cur_sectors(bio);
+ req->nr_phys_segments = bio_phys_segments(req->q, bio);
+ req->nr_hw_segments = bio_hw_segments(req->q, bio);
+ req->buffer = bio_data(bio); /* see ->buffer comment above */
+ req->waiting = NULL;
+ req->bio = req->biotail = bio;
+ req->ioprio = bio_prio(bio);
+ req->rq_disk = bio->bi_bdev->bd_disk;
+ req->start_time = jiffies;
+}
+
static int __make_request(request_queue_t *q, struct bio *bio)
{
struct request *req;
@@ -2680,7 +2814,7 @@ static int __make_request(request_queue_t *q, struct bio *bio)
spin_lock_prefetch(q->queue_lock);
barrier = bio_barrier(bio);
- if (unlikely(barrier) && (q->ordered == QUEUE_ORDERED_NONE)) {
+ if (unlikely(barrier) && (q->next_ordered == QUEUE_ORDERED_NONE)) {
err = -EOPNOTSUPP;
goto end_io;
}
@@ -2750,33 +2884,7 @@ get_rq:
* We don't worry about that case for efficiency. It won't happen
* often, and the elevators are able to handle it.
*/
-
- req->flags |= REQ_CMD;
-
- /*
- * inherit FAILFAST from bio (for read-ahead, and explicit FAILFAST)
- */
- if (bio_rw_ahead(bio) || bio_failfast(bio))
- req->flags |= REQ_FAILFAST;
-
- /*
- * REQ_BARRIER implies no merging, but lets make it explicit
- */
- if (unlikely(barrier))
- req->flags |= (REQ_HARDBARRIER | REQ_NOMERGE);
-
- req->errors = 0;
- req->hard_sector = req->sector = sector;
- req->hard_nr_sectors = req->nr_sectors = nr_sectors;
- req->current_nr_sectors = req->hard_cur_sectors = cur_nr_sectors;
- req->nr_phys_segments = bio_phys_segments(q, bio);
- req->nr_hw_segments = bio_hw_segments(q, bio);
- req->buffer = bio_data(bio); /* see ->buffer comment above */
- req->waiting = NULL;
- req->bio = req->biotail = bio;
- req->ioprio = prio;
- req->rq_disk = bio->bi_bdev->bd_disk;
- req->start_time = jiffies;
+ init_request_from_bio(req, bio);
spin_lock_irq(q->queue_lock);
if (elv_queue_empty(q))
@@ -3067,7 +3175,8 @@ static int __end_that_request_first(struct request *req, int uptodate,
if (nr_bytes >= bio->bi_size) {
req->bio = bio->bi_next;
nbytes = bio->bi_size;
- bio_endio(bio, nbytes, error);
+ if (!ordered_bio_endio(req, bio, nbytes, error))
+ bio_endio(bio, nbytes, error);
next_idx = 0;
bio_nbytes = 0;
} else {
@@ -3122,7 +3231,8 @@ static int __end_that_request_first(struct request *req, int uptodate,
* if the request wasn't completed, update state
*/
if (bio_nbytes) {
- bio_endio(bio, bio_nbytes, error);
+ if (!ordered_bio_endio(req, bio, bio_nbytes, error))
+ bio_endio(bio, bio_nbytes, error);
bio->bi_idx += next_idx;
bio_iovec(bio)->bv_offset += nr_bytes;
bio_iovec(bio)->bv_len -= nr_bytes;
@@ -3179,9 +3289,17 @@ EXPORT_SYMBOL(end_that_request_chunk);
/*
* queue lock must be held
*/
-void end_that_request_last(struct request *req)
+void end_that_request_last(struct request *req, int uptodate)
{
struct gendisk *disk = req->rq_disk;
+ int error;
+
+ /*
+ * extend uptodate bool to allow < 0 value to be direct io error
+ */
+ error = 0;
+ if (end_io_error(uptodate))
+ error = !uptodate ? -EIO : uptodate;
if (unlikely(laptop_mode) && blk_fs_request(req))
laptop_io_completion();
@@ -3196,7 +3314,7 @@ void end_that_request_last(struct request *req)
disk->in_flight--;
}
if (req->end_io)
- req->end_io(req);
+ req->end_io(req, error);
else
__blk_put_request(req->q, req);
}
@@ -3208,7 +3326,7 @@ void end_request(struct request *req, int uptodate)
if (!end_that_request_first(req, uptodate, req->hard_cur_sectors)) {
add_disk_randomness(req->rq_disk);
blkdev_dequeue_request(req);
- end_that_request_last(req);
+ end_that_request_last(req, uptodate);
}
}
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index 1d8852f..c2ac36d 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -46,7 +46,7 @@ EXPORT_SYMBOL(scsi_command_size);
static int sg_get_version(int __user *p)
{
- static int sg_version_num = 30527;
+ static const int sg_version_num = 30527;
return put_user(sg_version_num, p);
}
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