#include <linux/compiler.h>
#include <linux/delay.h>
#include <linux/blktrace_api.h>
+#include <trace/block.h>
#include <linux/hash.h>
+#include <linux/uaccess.h>
-#include <asm/uaccess.h>
+#include "blk.h"
static DEFINE_SPINLOCK(elv_list_lock);
static LIST_HEAD(elv_list);
+DEFINE_TRACE(block_rq_abort);
+
/*
* Merge hash stuff.
*/
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_TRACE(block_rq_insert);
+DEFINE_TRACE(block_rq_issue);
+
/*
* Query io scheduler to see if the current process issuing bio may be
* merged with rq.
/*
* 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_discard(bio) != bio_discard(rq->bio))
+ return 0;
+
+ /*
* different data direction or already started, don't merge
*/
if (bio_data_dir(bio) != rq_data_dir(rq))
if (rq->rq_disk != bio->bi_bdev->bd_disk || rq->special)
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;
spin_lock(&elv_list_lock);
e = elevator_find(name);
+ if (!e) {
+ char elv[ELV_NAME_MAX + strlen("-iosched")];
+
+ spin_unlock(&elv_list_lock);
+
+ if (!strcmp(name, "anticipatory"))
+ sprintf(elv, "as-iosched");
+ else
+ sprintf(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;
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(q, e);
elevator_attach(q, eq, data);
return ret;
}
-
EXPORT_SYMBOL(elevator_init);
void elevator_exit(elevator_t *e)
kobject_put(&e->kobj);
}
-
EXPORT_SYMBOL(elevator_exit);
static void elv_activate_rq(struct request_queue *q, struct request *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)
return NULL;
}
-
EXPORT_SYMBOL(elv_rb_find);
/*
{
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 (blk_discard_rq(rq) != blk_discard_rq(pos))
+ break;
if (rq_data_dir(rq) != rq_data_dir(pos))
break;
- if (pos->cmd_flags & (REQ_SOFTBARRIER|REQ_HARDBARRIER|REQ_STARTED))
+ if (pos->cmd_flags & stop_flags)
break;
if (rq->sector >= boundary) {
if (pos->sector < boundary)
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(struct request_queue *q, struct request **req, struct bio *bio)
}
}
+ if (blk_queue_nomerges(q))
+ return ELEVATOR_NO_MERGE;
+
/*
* See if our hash lookup can find a potential backmerge.
*/
unsigned ordseq;
int unplug_it = 1;
- blk_add_trace_rq(q, rq, BLK_TA_INSERT);
+ trace_block_rq_insert(q, rq);
rq->q = q;
* processing.
*/
blk_remove_plug(q);
- q->request_fn(q);
+ blk_start_queueing(q);
break;
case ELEVATOR_INSERT_SORT:
- BUG_ON(!blk_fs_request(rq));
+ BUG_ON(!blk_fs_request(rq) && !blk_discard_rq(rq));
rq->cmd_flags |= REQ_SORTED;
q->nr_sorted++;
if (rq_mergeable(rq)) {
default:
printk(KERN_ERR "%s: bad insertion point %d\n",
- __FUNCTION__, where);
+ __func__, where);
BUG();
}
* this request is scheduling boundary, update
* end_sector
*/
- if (blk_fs_request(rq)) {
+ if (blk_fs_request(rq) || blk_discard_rq(rq)) {
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(struct request_queue *q, struct request *rq, int where,
__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(struct request_queue *q)
* not ever see it.
*/
if (blk_empty_barrier(rq)) {
- end_queued_request(rq, 1);
+ __blk_end_request(rq, 0, blk_rq_bytes(rq));
continue;
}
if (!(rq->cmd_flags & REQ_STARTED)) {
* not be passed by new incoming requests
*/
rq->cmd_flags |= REQ_STARTED;
- blk_add_trace_rq(q, rq, BLK_TA_ISSUE);
+ trace_block_rq_issue(q, rq);
}
if (!q->boundary_rq || q->boundary_rq == rq) {
q->boundary_rq = NULL;
}
- if ((rq->cmd_flags & REQ_DONTPREP) || !q->prep_rq_fn)
+ if (rq->cmd_flags & REQ_DONTPREP)
+ break;
+
+ if (q->dma_drain_size && rq->data_len) {
+ /*
+ * make sure space for the drain appears we
+ * know we can do this because max_hw_segments
+ * has been adjusted to be one fewer than the
+ * device can handle
+ */
+ rq->nr_phys_segments++;
+ }
+
+ if (!q->prep_rq_fn)
break;
ret = q->prep_rq_fn(q, rq);
* avoid resource deadlock. REQ_STARTED will
* prevent other fs requests from passing this one.
*/
+ if (q->dma_drain_size && rq->data_len &&
+ !(rq->cmd_flags & REQ_DONTPREP)) {
+ /*
+ * remove the space for the drain we added
+ * so that we don't add it again
+ */
+ --rq->nr_phys_segments;
+ }
+
rq = NULL;
break;
} else if (ret == BLKPREP_KILL) {
rq->cmd_flags |= REQ_QUIET;
- end_queued_request(rq, 0);
+ __blk_end_request(rq, -EIO, blk_rq_bytes(rq));
} else {
- printk(KERN_ERR "%s: bad return=%d\n", __FUNCTION__,
- ret);
+ printk(KERN_ERR "%s: bad return=%d\n", __func__, ret);
break;
}
}
return rq;
}
-
EXPORT_SYMBOL(elv_next_request);
void elv_dequeue_request(struct request_queue *q, struct request *rq)
q->in_flight++;
}
-EXPORT_SYMBOL(elv_dequeue_request);
-
int elv_queue_empty(struct request_queue *q)
{
elevator_t *e = q->elevator;
return 1;
}
-
EXPORT_SYMBOL(elv_queue_empty);
struct request *elv_latter_request(struct request_queue *q, struct request *rq)
return ELV_MQUEUE_MAY;
}
+void elv_abort_queue(struct request_queue *q)
+{
+ 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);
+ __blk_end_request(rq, -EIO, blk_rq_bytes(rq));
+ }
+}
+EXPORT_SYMBOL(elv_abort_queue);
+
void elv_completed_request(struct request_queue *q, struct request *rq)
{
elevator_t *e = q->elevator;
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);
+ blk_start_queueing(q);
}
}
}
!strcmp(e->elevator_name, CONFIG_DEFAULT_IOSCHED)))
def = " (default)";
- printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name, def);
+ printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name,
+ def);
}
EXPORT_SYMBOL_GPL(elv_register);
*/
spin_lock_irq(q->queue_lock);
- set_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
+ queue_flag_set(QUEUE_FLAG_ELVSWITCH, q);
elv_drain_elevator(q);
while (q->rq.elvpriv) {
- blk_remove_plug(q);
- q->request_fn(q);
+ blk_start_queueing(q);
spin_unlock_irq(q->queue_lock);
msleep(10);
spin_lock_irq(q->queue_lock);
* finally exit old elevator and turn off BYPASS.
*/
elevator_exit(old_elevator);
- clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
+ spin_lock_irq(q->queue_lock);
+ queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q);
+ spin_unlock_irq(q->queue_lock);
+
+ blk_add_trace_msg(q, "elv switch: %s", e->elevator_type->elevator_name);
+
return 1;
fail_register:
elevator_exit(e);
q->elevator = old_elevator;
elv_register_queue(q);
- clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
+
+ spin_lock_irq(q->queue_lock);
+ queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q);
+ spin_unlock_irq(q->queue_lock);
+
return 0;
}
size_t count)
{
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';
+ strlcpy(elevator_name, name, sizeof(elevator_name));
+ strstrip(elevator_name);
e = elevator_get(elevator_name);
if (!e) {
}
if (!elevator_switch(q, e))
- printk(KERN_ERR "elevator: switch to %s failed\n",elevator_name);
+ printk(KERN_ERR "elevator: switch to %s failed\n",
+ elevator_name);
return count;
}
return NULL;
}
-
EXPORT_SYMBOL(elv_rb_former_request);
struct request *elv_rb_latter_request(struct request_queue *q,
return NULL;
}
-
EXPORT_SYMBOL(elv_rb_latter_request);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff