*
* Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE
*
- * 30042000 Jens Axboe <axboe@suse.de> :
+ * 30042000 Jens Axboe <axboe@kernel.dk> :
*
* Split the elevator a bit so that it is possible to choose a different
* one or even write a new "plug in". There are three pieces:
#include <linux/delay.h>
#include <linux/blktrace_api.h>
#include <linux/hash.h>
+#include <linux/uaccess.h>
-#include <asm/uaccess.h>
+#include <trace/events/block.h>
+
+#include "blk.h"
static DEFINE_SPINLOCK(elv_list_lock);
static LIST_HEAD(elv_list);
*/
static const int elv_hash_shift = 6;
#define ELV_HASH_BLOCK(sec) ((sec) >> 3)
-#define ELV_HASH_FN(sec) (hash_long(ELV_HASH_BLOCK((sec)), elv_hash_shift))
+#define ELV_HASH_FN(sec) \
+ (hash_long(ELV_HASH_BLOCK((sec)), elv_hash_shift))
#define ELV_HASH_ENTRIES (1 << elv_hash_shift)
-#define rq_hash_key(rq) ((rq)->sector + (rq)->nr_sectors)
-#define ELV_ON_HASH(rq) (!hlist_unhashed(&(rq)->hash))
+#define rq_hash_key(rq) (blk_rq_pos(rq) + blk_rq_sectors(rq))
+
+/*
+ * Query io scheduler to see if the current process issuing bio may be
+ * merged with rq.
+ */
+static int elv_iosched_allow_merge(struct request *rq, struct bio *bio)
+{
+ struct request_queue *q = rq->q;
+ struct elevator_queue *e = q->elevator;
+
+ if (e->ops->elevator_allow_merge_fn)
+ return e->ops->elevator_allow_merge_fn(q, rq, bio);
+
+ return 1;
+}
/*
* can we safely merge with this request?
*/
-inline int elv_rq_merge_ok(struct request *rq, struct bio *bio)
+int elv_rq_merge_ok(struct request *rq, struct bio *bio)
{
if (!rq_mergeable(rq))
return 0;
+ /*
+ * Don't merge file system requests and discard requests
+ */
+ if ((bio->bi_rw & REQ_DISCARD) != (rq->bio->bi_rw & REQ_DISCARD))
+ return 0;
+
+ /*
+ * Don't merge discard requests and secure discard requests
+ */
+ if ((bio->bi_rw & REQ_SECURE) != (rq->bio->bi_rw & REQ_SECURE))
+ return 0;
+
/*
* different data direction or already started, don't merge
*/
return 0;
/*
- * same device and no special stuff set, merge is ok
+ * must be same device and not a special request
*/
- if (rq->rq_disk == bio->bi_bdev->bd_disk && !rq->special)
- return 1;
+ if (rq->rq_disk != bio->bi_bdev->bd_disk || rq->special)
+ return 0;
- return 0;
+ /*
+ * only merge integrity protected bio into ditto rq
+ */
+ if (bio_integrity(bio) != blk_integrity_rq(rq))
+ return 0;
+
+ if (!elv_iosched_allow_merge(rq, bio))
+ return 0;
+
+ return 1;
}
EXPORT_SYMBOL(elv_rq_merge_ok);
* we can merge and sequence is ok, check if it's possible
*/
if (elv_rq_merge_ok(__rq, bio)) {
- if (__rq->sector + __rq->nr_sectors == bio->bi_sector)
+ if (blk_rq_pos(__rq) + blk_rq_sectors(__rq) == bio->bi_sector)
ret = ELEVATOR_BACK_MERGE;
- else if (__rq->sector - bio_sectors(bio) == bio->bi_sector)
+ else if (blk_rq_pos(__rq) - bio_sectors(bio) == bio->bi_sector)
ret = ELEVATOR_FRONT_MERGE;
}
static struct elevator_type *elevator_find(const char *name)
{
- struct elevator_type *e = NULL;
- struct list_head *entry;
-
- list_for_each(entry, &elv_list) {
- struct elevator_type *__e;
-
- __e = list_entry(entry, struct elevator_type, list);
+ struct elevator_type *e;
- if (!strcmp(__e->elevator_name, name)) {
- e = __e;
- break;
- }
+ list_for_each_entry(e, &elv_list, list) {
+ if (!strcmp(e->elevator_name, name))
+ return e;
}
- return e;
+ return NULL;
}
static void elevator_put(struct elevator_type *e)
{
struct elevator_type *e;
- spin_lock_irq(&elv_list_lock);
+ spin_lock(&elv_list_lock);
e = elevator_find(name);
+ if (!e) {
+ char elv[ELV_NAME_MAX + strlen("-iosched")];
+
+ spin_unlock(&elv_list_lock);
+
+ snprintf(elv, sizeof(elv), "%s-iosched", name);
+
+ request_module("%s", elv);
+ spin_lock(&elv_list_lock);
+ e = elevator_find(name);
+ }
+
if (e && !try_module_get(e->elevator_owner))
e = NULL;
- spin_unlock_irq(&elv_list_lock);
+ spin_unlock(&elv_list_lock);
return e;
}
-static void *elevator_init_queue(request_queue_t *q, struct elevator_queue *eq)
+static void *elevator_init_queue(struct request_queue *q,
+ struct elevator_queue *eq)
{
- return eq->ops->elevator_init_fn(q, eq);
+ return eq->ops->elevator_init_fn(q);
}
-static void elevator_attach(request_queue_t *q, struct elevator_queue *eq,
+static void elevator_attach(struct request_queue *q, struct elevator_queue *eq,
void *data)
{
q->elevator = eq;
* Be backwards-compatible with previous kernels, so users
* won't get the wrong elevator.
*/
- if (!strcmp(str, "as"))
- strcpy(chosen_elevator, "anticipatory");
- else
- strncpy(chosen_elevator, str, sizeof(chosen_elevator) - 1);
+ strncpy(chosen_elevator, str, sizeof(chosen_elevator) - 1);
return 1;
}
static struct kobj_type elv_ktype;
-static elevator_t *elevator_alloc(struct elevator_type *e)
+static struct elevator_queue *elevator_alloc(struct request_queue *q,
+ struct elevator_type *e)
{
- elevator_t *eq;
+ struct elevator_queue *eq;
int i;
- eq = kmalloc(sizeof(elevator_t), GFP_KERNEL);
+ eq = kmalloc_node(sizeof(*eq), GFP_KERNEL | __GFP_ZERO, q->node);
if (unlikely(!eq))
goto err;
- memset(eq, 0, sizeof(*eq));
eq->ops = &e->ops;
eq->elevator_type = e;
- kobject_init(&eq->kobj);
- snprintf(eq->kobj.name, KOBJ_NAME_LEN, "%s", "iosched");
- eq->kobj.ktype = &elv_ktype;
+ kobject_init(&eq->kobj, &elv_ktype);
mutex_init(&eq->sysfs_lock);
- eq->hash = kmalloc(sizeof(struct hlist_head) * ELV_HASH_ENTRIES, GFP_KERNEL);
+ eq->hash = kmalloc_node(sizeof(struct hlist_head) * ELV_HASH_ENTRIES,
+ GFP_KERNEL, q->node);
if (!eq->hash)
goto err;
static void elevator_release(struct kobject *kobj)
{
- elevator_t *e = container_of(kobj, elevator_t, kobj);
+ struct elevator_queue *e;
+ e = container_of(kobj, struct elevator_queue, kobj);
elevator_put(e->elevator_type);
kfree(e->hash);
kfree(e);
}
-int elevator_init(request_queue_t *q, char *name)
+int elevator_init(struct request_queue *q, char *name)
{
struct elevator_type *e = NULL;
struct elevator_queue *eq;
- int ret = 0;
void *data;
+ if (unlikely(q->elevator))
+ return 0;
+
INIT_LIST_HEAD(&q->queue_head);
q->last_merge = NULL;
q->end_sector = 0;
q->boundary_rq = NULL;
- if (name && !(e = elevator_get(name)))
- return -EINVAL;
+ if (name) {
+ e = elevator_get(name);
+ if (!e)
+ return -EINVAL;
+ }
- if (!e && *chosen_elevator && !(e = elevator_get(chosen_elevator)))
- printk("I/O scheduler %s not found\n", chosen_elevator);
+ if (!e && *chosen_elevator) {
+ e = elevator_get(chosen_elevator);
+ if (!e)
+ printk(KERN_ERR "I/O scheduler %s not found\n",
+ chosen_elevator);
+ }
- if (!e && !(e = elevator_get(CONFIG_DEFAULT_IOSCHED))) {
- printk("Default I/O scheduler not found, using no-op\n");
- e = elevator_get("noop");
+ if (!e) {
+ e = elevator_get(CONFIG_DEFAULT_IOSCHED);
+ if (!e) {
+ printk(KERN_ERR
+ "Default I/O scheduler not found. " \
+ "Using noop.\n");
+ e = elevator_get("noop");
+ }
}
- eq = elevator_alloc(e);
+ eq = elevator_alloc(q, e);
if (!eq)
return -ENOMEM;
}
elevator_attach(q, eq, data);
- return ret;
+ return 0;
}
-
EXPORT_SYMBOL(elevator_init);
-void elevator_exit(elevator_t *e)
+void elevator_exit(struct elevator_queue *e)
{
mutex_lock(&e->sysfs_lock);
if (e->ops->elevator_exit_fn)
kobject_put(&e->kobj);
}
-
EXPORT_SYMBOL(elevator_exit);
static inline void __elv_rqhash_del(struct request *rq)
hlist_del_init(&rq->hash);
}
-static void elv_rqhash_del(request_queue_t *q, struct request *rq)
+static void elv_rqhash_del(struct request_queue *q, struct request *rq)
{
if (ELV_ON_HASH(rq))
__elv_rqhash_del(rq);
}
-static void elv_rqhash_add(request_queue_t *q, struct request *rq)
+static void elv_rqhash_add(struct request_queue *q, struct request *rq)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
BUG_ON(ELV_ON_HASH(rq));
hlist_add_head(&rq->hash, &e->hash[ELV_HASH_FN(rq_hash_key(rq))]);
}
-static void elv_rqhash_reposition(request_queue_t *q, struct request *rq)
+static void elv_rqhash_reposition(struct request_queue *q, struct request *rq)
{
__elv_rqhash_del(rq);
elv_rqhash_add(q, rq);
}
-static struct request *elv_rqhash_find(request_queue_t *q, sector_t offset)
+static struct request *elv_rqhash_find(struct request_queue *q, sector_t offset)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
struct hlist_head *hash_list = &e->hash[ELV_HASH_FN(offset)];
struct hlist_node *entry, *next;
struct request *rq;
parent = *p;
__rq = rb_entry(parent, struct request, rb_node);
- if (rq->sector < __rq->sector)
+ if (blk_rq_pos(rq) < blk_rq_pos(__rq))
p = &(*p)->rb_left;
- else if (rq->sector > __rq->sector)
+ else if (blk_rq_pos(rq) > blk_rq_pos(__rq))
p = &(*p)->rb_right;
else
return __rq;
rb_insert_color(&rq->rb_node, root);
return NULL;
}
-
EXPORT_SYMBOL(elv_rb_add);
void elv_rb_del(struct rb_root *root, struct request *rq)
rb_erase(&rq->rb_node, root);
RB_CLEAR_NODE(&rq->rb_node);
}
-
EXPORT_SYMBOL(elv_rb_del);
struct request *elv_rb_find(struct rb_root *root, sector_t sector)
while (n) {
rq = rb_entry(n, struct request, rb_node);
- if (sector < rq->sector)
+ if (sector < blk_rq_pos(rq))
n = n->rb_left;
- else if (sector > rq->sector)
+ else if (sector > blk_rq_pos(rq))
n = n->rb_right;
else
return rq;
return NULL;
}
-
EXPORT_SYMBOL(elv_rb_find);
/*
* Insert rq into dispatch queue of q. Queue lock must be held on
- * entry. rq is sort insted into the dispatch queue. To be used by
+ * entry. rq is sort instead into the dispatch queue. To be used by
* specific elevators.
*/
-void elv_dispatch_sort(request_queue_t *q, struct request *rq)
+void elv_dispatch_sort(struct request_queue *q, struct request *rq)
{
sector_t boundary;
struct list_head *entry;
+ int stop_flags;
if (q->last_merge == rq)
q->last_merge = NULL;
q->nr_sorted--;
boundary = q->end_sector;
-
+ stop_flags = REQ_SOFTBARRIER | REQ_HARDBARRIER | REQ_STARTED;
list_for_each_prev(entry, &q->queue_head) {
struct request *pos = list_entry_rq(entry);
- if (pos->cmd_flags & (REQ_SOFTBARRIER|REQ_HARDBARRIER|REQ_STARTED))
+ if ((rq->cmd_flags & REQ_DISCARD) !=
+ (pos->cmd_flags & REQ_DISCARD))
break;
- if (rq->sector >= boundary) {
- if (pos->sector < boundary)
+ if (rq_data_dir(rq) != rq_data_dir(pos))
+ break;
+ if (pos->cmd_flags & stop_flags)
+ break;
+ if (blk_rq_pos(rq) >= boundary) {
+ if (blk_rq_pos(pos) < boundary)
continue;
} else {
- if (pos->sector >= boundary)
+ if (blk_rq_pos(pos) >= boundary)
break;
}
- if (rq->sector >= pos->sector)
+ if (blk_rq_pos(rq) >= blk_rq_pos(pos))
break;
}
list_add(&rq->queuelist, entry);
}
-
EXPORT_SYMBOL(elv_dispatch_sort);
/*
q->boundary_rq = rq;
list_add_tail(&rq->queuelist, &q->queue_head);
}
-
EXPORT_SYMBOL(elv_dispatch_add_tail);
-int elv_merge(request_queue_t *q, struct request **req, struct bio *bio)
+int elv_merge(struct request_queue *q, struct request **req, struct bio *bio)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
struct request *__rq;
int ret;
+ /*
+ * Levels of merges:
+ * nomerges: No merges at all attempted
+ * noxmerges: Only simple one-hit cache try
+ * merges: All merge tries attempted
+ */
+ if (blk_queue_nomerges(q))
+ return ELEVATOR_NO_MERGE;
+
/*
* First try one-hit cache.
*/
}
}
+ if (blk_queue_noxmerges(q))
+ return ELEVATOR_NO_MERGE;
+
/*
* See if our hash lookup can find a potential backmerge.
*/
return ELEVATOR_NO_MERGE;
}
-void elv_merged_request(request_queue_t *q, struct request *rq, int type)
+void elv_merged_request(struct request_queue *q, struct request *rq, int type)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
if (e->ops->elevator_merged_fn)
e->ops->elevator_merged_fn(q, rq, type);
q->last_merge = rq;
}
-void elv_merge_requests(request_queue_t *q, struct request *rq,
+void elv_merge_requests(struct request_queue *q, struct request *rq,
struct request *next)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
if (e->ops->elevator_merge_req_fn)
e->ops->elevator_merge_req_fn(q, rq, next);
q->last_merge = rq;
}
-void elv_requeue_request(request_queue_t *q, struct request *rq)
+void elv_bio_merged(struct request_queue *q, struct request *rq,
+ struct bio *bio)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
+
+ if (e->ops->elevator_bio_merged_fn)
+ e->ops->elevator_bio_merged_fn(q, rq, bio);
+}
+void elv_requeue_request(struct request_queue *q, struct request *rq)
+{
/*
* it already went through dequeue, we need to decrement the
* in_flight count again
*/
if (blk_account_rq(rq)) {
- q->in_flight--;
- if (blk_sorted_rq(rq) && e->ops->elevator_deactivate_req_fn)
- e->ops->elevator_deactivate_req_fn(q, rq);
+ q->in_flight[rq_is_sync(rq)]--;
+ if (rq->cmd_flags & REQ_SORTED)
+ elv_deactivate_rq(q, rq);
}
rq->cmd_flags &= ~REQ_STARTED;
elv_insert(q, rq, ELEVATOR_INSERT_REQUEUE);
}
-static void elv_drain_elevator(request_queue_t *q)
+void elv_drain_elevator(struct request_queue *q)
{
static int printed;
while (q->elevator->ops->elevator_dispatch_fn(q, 1))
}
}
-void elv_insert(request_queue_t *q, struct request *rq, int where)
+/*
+ * Call with queue lock held, interrupts disabled
+ */
+void elv_quiesce_start(struct request_queue *q)
+{
+ if (!q->elevator)
+ return;
+
+ queue_flag_set(QUEUE_FLAG_ELVSWITCH, q);
+
+ /*
+ * make sure we don't have any requests in flight
+ */
+ elv_drain_elevator(q);
+ while (q->rq.elvpriv) {
+ __blk_run_queue(q);
+ spin_unlock_irq(q->queue_lock);
+ msleep(10);
+ spin_lock_irq(q->queue_lock);
+ elv_drain_elevator(q);
+ }
+}
+
+void elv_quiesce_end(struct request_queue *q)
+{
+ queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q);
+}
+
+void elv_insert(struct request_queue *q, struct request *rq, int where)
{
struct list_head *pos;
unsigned ordseq;
int unplug_it = 1;
- blk_add_trace_rq(q, rq, BLK_TA_INSERT);
+ trace_block_rq_insert(q, rq);
rq->q = q;
* with anything. There's no point in delaying queue
* processing.
*/
- blk_remove_plug(q);
- q->request_fn(q);
+ __blk_run_queue(q);
break;
case ELEVATOR_INSERT_SORT:
- BUG_ON(!blk_fs_request(rq));
+ BUG_ON(rq->cmd_type != REQ_TYPE_FS &&
+ !(rq->cmd_flags & REQ_DISCARD));
rq->cmd_flags |= REQ_SORTED;
q->nr_sorted++;
if (rq_mergeable(rq)) {
*/
rq->cmd_flags |= REQ_SOFTBARRIER;
+ /*
+ * Most requeues happen because of a busy condition,
+ * don't force unplug of the queue for that case.
+ */
+ unplug_it = 0;
+
if (q->ordseq == 0) {
list_add(&rq->queuelist, &q->queue_head);
break;
}
list_add_tail(&rq->queuelist, pos);
- /*
- * most requeues happen because of a busy condition, don't
- * force unplug of the queue for that case.
- */
- unplug_it = 0;
break;
default:
printk(KERN_ERR "%s: bad insertion point %d\n",
- __FUNCTION__, where);
+ __func__, where);
BUG();
}
if (unplug_it && blk_queue_plugged(q)) {
- int nrq = q->rq.count[READ] + q->rq.count[WRITE]
- - q->in_flight;
+ int nrq = q->rq.count[BLK_RW_SYNC] + q->rq.count[BLK_RW_ASYNC]
+ - queue_in_flight(q);
if (nrq >= q->unplug_thresh)
__generic_unplug_device(q);
}
}
-void __elv_add_request(request_queue_t *q, struct request *rq, int where,
+void __elv_add_request(struct request_queue *q, struct request *rq, int where,
int plug)
{
if (q->ordcolor)
/*
* toggle ordered color
*/
- if (blk_barrier_rq(rq))
+ if (rq->cmd_flags & REQ_HARDBARRIER)
q->ordcolor ^= 1;
/*
* this request is scheduling boundary, update
* end_sector
*/
- if (blk_fs_request(rq)) {
+ if (rq->cmd_type == REQ_TYPE_FS ||
+ (rq->cmd_flags & REQ_DISCARD)) {
q->end_sector = rq_end_sector(rq);
q->boundary_rq = rq;
}
- } else if (!(rq->cmd_flags & REQ_ELVPRIV) && where == ELEVATOR_INSERT_SORT)
+ } else if (!(rq->cmd_flags & REQ_ELVPRIV) &&
+ where == ELEVATOR_INSERT_SORT)
where = ELEVATOR_INSERT_BACK;
if (plug)
elv_insert(q, rq, where);
}
-
EXPORT_SYMBOL(__elv_add_request);
-void elv_add_request(request_queue_t *q, struct request *rq, int where,
+void elv_add_request(struct request_queue *q, struct request *rq, int where,
int plug)
{
unsigned long flags;
__elv_add_request(q, rq, where, plug);
spin_unlock_irqrestore(q->queue_lock, flags);
}
-
EXPORT_SYMBOL(elv_add_request);
-static inline struct request *__elv_next_request(request_queue_t *q)
+int elv_queue_empty(struct request_queue *q)
{
- struct request *rq;
-
- 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->elevator->ops->elevator_dispatch_fn(q, 0))
- return NULL;
- }
-}
-
-struct request *elv_next_request(request_queue_t *q)
-{
- struct request *rq;
- int ret;
-
- while ((rq = __elv_next_request(q)) != NULL) {
- if (!(rq->cmd_flags & REQ_STARTED)) {
- elevator_t *e = q->elevator;
-
- /*
- * This is the first time the device driver
- * sees this request (possibly after
- * requeueing). Notify IO scheduler.
- */
- if (blk_sorted_rq(rq) &&
- e->ops->elevator_activate_req_fn)
- e->ops->elevator_activate_req_fn(q, rq);
-
- /*
- * just mark as started even if we don't start
- * it, a request that has been delayed should
- * not be passed by new incoming requests
- */
- rq->cmd_flags |= REQ_STARTED;
- blk_add_trace_rq(q, rq, BLK_TA_ISSUE);
- }
-
- if (!q->boundary_rq || q->boundary_rq == rq) {
- q->end_sector = rq_end_sector(rq);
- q->boundary_rq = NULL;
- }
-
- if ((rq->cmd_flags & REQ_DONTPREP) || !q->prep_rq_fn)
- break;
-
- ret = q->prep_rq_fn(q, rq);
- if (ret == BLKPREP_OK) {
- break;
- } else if (ret == BLKPREP_DEFER) {
- /*
- * the request may have been (partially) prepped.
- * we need to keep this request in the front to
- * avoid resource deadlock. REQ_STARTED will
- * prevent other fs requests from passing this one.
- */
- rq = NULL;
- break;
- } else if (ret == BLKPREP_KILL) {
- int nr_bytes = rq->hard_nr_sectors << 9;
-
- if (!nr_bytes)
- nr_bytes = rq->data_len;
-
- blkdev_dequeue_request(rq);
- rq->cmd_flags |= REQ_QUIET;
- end_that_request_chunk(rq, 0, nr_bytes);
- end_that_request_last(rq, 0);
- } else {
- printk(KERN_ERR "%s: bad return=%d\n", __FUNCTION__,
- ret);
- break;
- }
- }
-
- return rq;
-}
-
-EXPORT_SYMBOL(elv_next_request);
-
-void elv_dequeue_request(request_queue_t *q, struct request *rq)
-{
- BUG_ON(list_empty(&rq->queuelist));
- BUG_ON(ELV_ON_HASH(rq));
-
- list_del_init(&rq->queuelist);
-
- /*
- * the time frame between a request being removed from the lists
- * and to it is freed is accounted as io that is in progress at
- * the driver side.
- */
- if (blk_account_rq(rq))
- q->in_flight++;
-}
-
-EXPORT_SYMBOL(elv_dequeue_request);
-
-int elv_queue_empty(request_queue_t *q)
-{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
if (!list_empty(&q->queue_head))
return 0;
return 1;
}
-
EXPORT_SYMBOL(elv_queue_empty);
-struct request *elv_latter_request(request_queue_t *q, struct request *rq)
+struct request *elv_latter_request(struct request_queue *q, struct request *rq)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
if (e->ops->elevator_latter_req_fn)
return e->ops->elevator_latter_req_fn(q, rq);
return NULL;
}
-struct request *elv_former_request(request_queue_t *q, struct request *rq)
+struct request *elv_former_request(struct request_queue *q, struct request *rq)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
if (e->ops->elevator_former_req_fn)
return e->ops->elevator_former_req_fn(q, rq);
return NULL;
}
-int elv_set_request(request_queue_t *q, struct request *rq, struct bio *bio,
- gfp_t gfp_mask)
+int elv_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
if (e->ops->elevator_set_req_fn)
- return e->ops->elevator_set_req_fn(q, rq, bio, gfp_mask);
+ return e->ops->elevator_set_req_fn(q, rq, gfp_mask);
rq->elevator_private = NULL;
return 0;
}
-void elv_put_request(request_queue_t *q, struct request *rq)
+void elv_put_request(struct request_queue *q, struct request *rq)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
if (e->ops->elevator_put_req_fn)
- e->ops->elevator_put_req_fn(q, rq);
+ e->ops->elevator_put_req_fn(rq);
}
-int elv_may_queue(request_queue_t *q, int rw, struct bio *bio)
+int elv_may_queue(struct request_queue *q, int rw)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
if (e->ops->elevator_may_queue_fn)
- return e->ops->elevator_may_queue_fn(q, rw, bio);
+ return e->ops->elevator_may_queue_fn(q, rw);
return ELV_MQUEUE_MAY;
}
-void elv_completed_request(request_queue_t *q, struct request *rq)
+void elv_abort_queue(struct request_queue *q)
{
- elevator_t *e = q->elevator;
+ struct request *rq;
+
+ while (!list_empty(&q->queue_head)) {
+ rq = list_entry_rq(q->queue_head.next);
+ rq->cmd_flags |= REQ_QUIET;
+ trace_block_rq_abort(q, rq);
+ /*
+ * Mark this request as started so we don't trigger
+ * any debug logic in the end I/O path.
+ */
+ blk_start_request(rq);
+ __blk_end_request_all(rq, -EIO);
+ }
+}
+EXPORT_SYMBOL(elv_abort_queue);
+
+void elv_completed_request(struct request_queue *q, struct request *rq)
+{
+ struct elevator_queue *e = q->elevator;
/*
* request is released from the driver, io must be done
*/
if (blk_account_rq(rq)) {
- q->in_flight--;
- if (blk_sorted_rq(rq) && e->ops->elevator_completed_req_fn)
+ q->in_flight[rq_is_sync(rq)]--;
+ if ((rq->cmd_flags & REQ_SORTED) &&
+ e->ops->elevator_completed_req_fn)
e->ops->elevator_completed_req_fn(q, rq);
}
* drained for flush sequence.
*/
if (unlikely(q->ordseq)) {
- struct request *first_rq = list_entry_rq(q->queue_head.next);
- if (q->in_flight == 0 &&
+ struct request *next = NULL;
+
+ if (!list_empty(&q->queue_head))
+ next = list_entry_rq(q->queue_head.next);
+
+ if (!queue_in_flight(q) &&
blk_ordered_cur_seq(q) == QUEUE_ORDSEQ_DRAIN &&
- blk_ordered_req_seq(first_rq) > QUEUE_ORDSEQ_DRAIN) {
+ (!next || blk_ordered_req_seq(next) > QUEUE_ORDSEQ_DRAIN)) {
blk_ordered_complete_seq(q, QUEUE_ORDSEQ_DRAIN, 0);
- q->request_fn(q);
+ __blk_run_queue(q);
}
}
}
static ssize_t
elv_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
{
- elevator_t *e = container_of(kobj, elevator_t, kobj);
struct elv_fs_entry *entry = to_elv(attr);
+ struct elevator_queue *e;
ssize_t error;
if (!entry->show)
return -EIO;
+ e = container_of(kobj, struct elevator_queue, kobj);
mutex_lock(&e->sysfs_lock);
error = e->ops ? entry->show(e, page) : -ENOENT;
mutex_unlock(&e->sysfs_lock);
elv_attr_store(struct kobject *kobj, struct attribute *attr,
const char *page, size_t length)
{
- elevator_t *e = container_of(kobj, elevator_t, kobj);
struct elv_fs_entry *entry = to_elv(attr);
+ struct elevator_queue *e;
ssize_t error;
if (!entry->store)
return -EIO;
+ e = container_of(kobj, struct elevator_queue, kobj);
mutex_lock(&e->sysfs_lock);
error = e->ops ? entry->store(e, page, length) : -ENOENT;
mutex_unlock(&e->sysfs_lock);
return error;
}
-static struct sysfs_ops elv_sysfs_ops = {
+static const struct sysfs_ops elv_sysfs_ops = {
.show = elv_attr_show,
.store = elv_attr_store,
};
int elv_register_queue(struct request_queue *q)
{
- elevator_t *e = q->elevator;
+ struct elevator_queue *e = q->elevator;
int error;
- e->kobj.parent = &q->kobj;
-
- error = kobject_add(&e->kobj);
+ error = kobject_add(&e->kobj, &q->kobj, "%s", "iosched");
if (!error) {
struct elv_fs_entry *attr = e->elevator_type->elevator_attrs;
if (attr) {
}
}
kobject_uevent(&e->kobj, KOBJ_ADD);
+ e->registered = 1;
}
return error;
}
+EXPORT_SYMBOL(elv_register_queue);
-static void __elv_unregister_queue(elevator_t *e)
+static void __elv_unregister_queue(struct elevator_queue *e)
{
kobject_uevent(&e->kobj, KOBJ_REMOVE);
kobject_del(&e->kobj);
+ e->registered = 0;
}
void elv_unregister_queue(struct request_queue *q)
if (q)
__elv_unregister_queue(q->elevator);
}
+EXPORT_SYMBOL(elv_unregister_queue);
-int elv_register(struct elevator_type *e)
+void elv_register(struct elevator_type *e)
{
- spin_lock_irq(&elv_list_lock);
+ char *def = "";
+
+ spin_lock(&elv_list_lock);
BUG_ON(elevator_find(e->elevator_name));
list_add_tail(&e->list, &elv_list);
- spin_unlock_irq(&elv_list_lock);
+ spin_unlock(&elv_list_lock);
- printk(KERN_INFO "io scheduler %s registered", e->elevator_name);
if (!strcmp(e->elevator_name, chosen_elevator) ||
(!*chosen_elevator &&
!strcmp(e->elevator_name, CONFIG_DEFAULT_IOSCHED)))
- printk(" (default)");
- printk("\n");
- return 0;
+ def = " (default)";
+
+ printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name,
+ def);
}
EXPORT_SYMBOL_GPL(elv_register);
read_unlock(&tasklist_lock);
}
- spin_lock_irq(&elv_list_lock);
+ spin_lock(&elv_list_lock);
list_del_init(&e->list);
- spin_unlock_irq(&elv_list_lock);
+ spin_unlock(&elv_list_lock);
}
EXPORT_SYMBOL_GPL(elv_unregister);
* need for the new one. this way we have a chance of going back to the old
* one, if the new one fails init for some reason.
*/
-static int elevator_switch(request_queue_t *q, struct elevator_type *new_e)
+static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
{
- elevator_t *old_elevator, *e;
+ struct elevator_queue *old_elevator, *e;
void *data;
+ int err;
/*
* Allocate new elevator
*/
- e = elevator_alloc(new_e);
+ e = elevator_alloc(q, new_e);
if (!e)
- return 0;
+ return -ENOMEM;
data = elevator_init_queue(q, e);
if (!data) {
kobject_put(&e->kobj);
- return 0;
+ return -ENOMEM;
}
/*
* Turn on BYPASS and drain all requests w/ elevator private data
*/
spin_lock_irq(q->queue_lock);
-
- set_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
-
- elv_drain_elevator(q);
-
- while (q->rq.elvpriv) {
- blk_remove_plug(q);
- q->request_fn(q);
- spin_unlock_irq(q->queue_lock);
- msleep(10);
- spin_lock_irq(q->queue_lock);
- elv_drain_elevator(q);
- }
+ elv_quiesce_start(q);
/*
* Remember old elevator.
spin_unlock_irq(q->queue_lock);
- __elv_unregister_queue(old_elevator);
+ if (old_elevator->registered) {
+ __elv_unregister_queue(old_elevator);
- if (elv_register_queue(q))
- goto fail_register;
+ err = elv_register_queue(q);
+ if (err)
+ goto fail_register;
+ }
/*
* finally exit old elevator and turn off BYPASS.
*/
elevator_exit(old_elevator);
- clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
- return 1;
+ spin_lock_irq(q->queue_lock);
+ elv_quiesce_end(q);
+ spin_unlock_irq(q->queue_lock);
+
+ blk_add_trace_msg(q, "elv switch: %s", e->elevator_type->elevator_name);
+
+ return 0;
fail_register:
/*
elevator_exit(e);
q->elevator = old_elevator;
elv_register_queue(q);
- clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
- return 0;
+
+ spin_lock_irq(q->queue_lock);
+ queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q);
+ spin_unlock_irq(q->queue_lock);
+
+ return err;
}
-ssize_t elv_iosched_store(request_queue_t *q, const char *name, size_t count)
+/*
+ * Switch this queue to the given IO scheduler.
+ */
+int elevator_change(struct request_queue *q, const char *name)
{
char elevator_name[ELV_NAME_MAX];
- size_t len;
struct elevator_type *e;
- elevator_name[sizeof(elevator_name) - 1] = '\0';
- strncpy(elevator_name, name, sizeof(elevator_name) - 1);
- len = strlen(elevator_name);
-
- if (len && elevator_name[len - 1] == '\n')
- elevator_name[len - 1] = '\0';
+ if (!q->elevator)
+ return -ENXIO;
- e = elevator_get(elevator_name);
+ strlcpy(elevator_name, name, sizeof(elevator_name));
+ e = elevator_get(strstrip(elevator_name));
if (!e) {
printk(KERN_ERR "elevator: type %s not found\n", elevator_name);
return -EINVAL;
if (!strcmp(elevator_name, q->elevator->elevator_type->elevator_name)) {
elevator_put(e);
- return count;
+ return 0;
}
- if (!elevator_switch(q, e))
- printk(KERN_ERR "elevator: switch to %s failed\n",elevator_name);
- return count;
+ return elevator_switch(q, e);
}
+EXPORT_SYMBOL(elevator_change);
-ssize_t elv_iosched_show(request_queue_t *q, char *name)
+ssize_t elv_iosched_store(struct request_queue *q, const char *name,
+ size_t count)
{
- elevator_t *e = q->elevator;
- struct elevator_type *elv = e->elevator_type;
- struct list_head *entry;
+ int ret;
+
+ if (!q->elevator)
+ return count;
+
+ ret = elevator_change(q, name);
+ if (!ret)
+ return count;
+
+ printk(KERN_ERR "elevator: switch to %s failed\n", name);
+ return ret;
+}
+
+ssize_t elv_iosched_show(struct request_queue *q, char *name)
+{
+ struct elevator_queue *e = q->elevator;
+ struct elevator_type *elv;
+ struct elevator_type *__e;
int len = 0;
- spin_lock_irq(q->queue_lock);
- list_for_each(entry, &elv_list) {
- struct elevator_type *__e;
+ if (!q->elevator || !blk_queue_stackable(q))
+ return sprintf(name, "none\n");
+
+ elv = e->elevator_type;
- __e = list_entry(entry, struct elevator_type, list);
+ spin_lock(&elv_list_lock);
+ list_for_each_entry(__e, &elv_list, list) {
if (!strcmp(elv->elevator_name, __e->elevator_name))
len += sprintf(name+len, "[%s] ", elv->elevator_name);
else
len += sprintf(name+len, "%s ", __e->elevator_name);
}
- spin_unlock_irq(q->queue_lock);
+ spin_unlock(&elv_list_lock);
len += sprintf(len+name, "\n");
return len;
}
-struct request *elv_rb_former_request(request_queue_t *q, struct request *rq)
+struct request *elv_rb_former_request(struct request_queue *q,
+ struct request *rq)
{
struct rb_node *rbprev = rb_prev(&rq->rb_node);
return NULL;
}
-
EXPORT_SYMBOL(elv_rb_former_request);
-struct request *elv_rb_latter_request(request_queue_t *q, struct request *rq)
+struct request *elv_rb_latter_request(struct request_queue *q,
+ struct request *rq)
{
struct rb_node *rbnext = rb_next(&rq->rb_node);
return NULL;
}
-
EXPORT_SYMBOL(elv_rb_latter_request);
Code Review / linux-2.6.git / blobdiff