block: set the bounce_pfn to the actual DMA limit rather than to max memory
[linux-2.6.git] / block / elevator.c
index ebee948..ec585c9 100644 (file)
 #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 <trace/events/block.h>
+
 #include "blk.h"
 
 static DEFINE_SPINLOCK(elv_list_lock);
 static LIST_HEAD(elv_list);
 
-DEFINE_TRACE(block_rq_abort);
-
 /*
  * Merge hash stuff.
  */
@@ -54,9 +53,6 @@ static const int elv_hash_shift = 6;
 #define ELV_HASH_ENTRIES       (1 << elv_hash_shift)
 #define rq_hash_key(rq)                (blk_rq_pos(rq) + blk_rq_sectors(rq))
 
-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.
@@ -83,7 +79,13 @@ int elv_rq_merge_ok(struct request *rq, struct bio *bio)
        /*
         * Don't merge file system requests and discard requests
         */
-       if (bio_discard(bio) != bio_discard(rq->bio))
+       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;
 
        /*
@@ -157,10 +159,7 @@ static struct elevator_type *elevator_get(const char *name)
 
                spin_unlock(&elv_list_lock);
 
-               if (!strcmp(name, "anticipatory"))
-                       sprintf(elv, "as-iosched");
-               else
-                       sprintf(elv, "%s-iosched", name);
+               snprintf(elv, sizeof(elv), "%s-iosched", name);
 
                request_module("%s", elv);
                spin_lock(&elv_list_lock);
@@ -196,10 +195,7 @@ static int __init elevator_setup(char *str)
         * 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;
 }
 
@@ -251,9 +247,11 @@ 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;
@@ -293,7 +291,7 @@ int elevator_init(struct request_queue *q, char *name)
        }
 
        elevator_attach(q, eq, data);
-       return ret;
+       return 0;
 }
 EXPORT_SYMBOL(elevator_init);
 
@@ -435,7 +433,8 @@ void elv_dispatch_sort(struct request_queue *q, struct request *rq)
        list_for_each_prev(entry, &q->queue_head) {
                struct request *pos = list_entry_rq(entry);
 
-               if (blk_discard_rq(rq) != blk_discard_rq(pos))
+               if ((rq->cmd_flags & REQ_DISCARD) !=
+                   (pos->cmd_flags & REQ_DISCARD))
                        break;
                if (rq_data_dir(rq) != rq_data_dir(pos))
                        break;
@@ -483,6 +482,15 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio)
        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 (q->last_merge) {
@@ -493,7 +501,7 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio)
                }
        }
 
-       if (blk_queue_nomerges(q))
+       if (blk_queue_noxmerges(q))
                return ELEVATOR_NO_MERGE;
 
        /*
@@ -539,6 +547,15 @@ void elv_merge_requests(struct request_queue *q, struct request *rq,
        q->last_merge = rq;
 }
 
+void elv_bio_merged(struct request_queue *q, struct request *rq,
+                       struct bio *bio)
+{
+       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)
 {
        /*
@@ -547,7 +564,7 @@ void elv_requeue_request(struct request_queue *q, struct request *rq)
         */
        if (blk_account_rq(rq)) {
                q->in_flight[rq_is_sync(rq)]--;
-               if (blk_sorted_rq(rq))
+               if (rq->cmd_flags & REQ_SORTED)
                        elv_deactivate_rq(q, rq);
        }
 
@@ -575,6 +592,9 @@ void elv_drain_elevator(struct request_queue *q)
  */
 void elv_quiesce_start(struct request_queue *q)
 {
+       if (!q->elevator)
+               return;
+
        queue_flag_set(QUEUE_FLAG_ELVSWITCH, q);
 
        /*
@@ -630,7 +650,8 @@ void elv_insert(struct request_queue *q, struct request *rq, int where)
                break;
 
        case ELEVATOR_INSERT_SORT:
-               BUG_ON(!blk_fs_request(rq) && !blk_discard_rq(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)) {
@@ -702,7 +723,7 @@ void __elv_add_request(struct request_queue *q, struct request *rq, int where,
                /*
                 * toggle ordered color
                 */
-               if (blk_barrier_rq(rq))
+               if (rq->cmd_flags & REQ_HARDBARRIER)
                        q->ordcolor ^= 1;
 
                /*
@@ -715,7 +736,8 @@ void __elv_add_request(struct request_queue *q, struct request *rq, int where,
                 * this request is scheduling boundary, update
                 * end_sector
                 */
-               if (blk_fs_request(rq) || blk_discard_rq(rq)) {
+               if (rq->cmd_type == REQ_TYPE_FS ||
+                   (rq->cmd_flags & REQ_DISCARD)) {
                        q->end_sector = rq_end_sector(rq);
                        q->boundary_rq = rq;
                }
@@ -810,6 +832,11 @@ void elv_abort_queue(struct request_queue *q)
                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);
        }
 }
@@ -824,7 +851,8 @@ void elv_completed_request(struct request_queue *q, struct request *rq)
         */
        if (blk_account_rq(rq)) {
                q->in_flight[rq_is_sync(rq)]--;
-               if (blk_sorted_rq(rq) && e->ops->elevator_completed_req_fn)
+               if ((rq->cmd_flags & REQ_SORTED) &&
+                   e->ops->elevator_completed_req_fn)
                        e->ops->elevator_completed_req_fn(q, rq);
        }
 
@@ -884,7 +912,7 @@ elv_attr_store(struct kobject *kobj, struct attribute *attr,
        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,
 };
@@ -913,6 +941,7 @@ int elv_register_queue(struct request_queue *q)
        }
        return error;
 }
+EXPORT_SYMBOL(elv_register_queue);
 
 static void __elv_unregister_queue(struct elevator_queue *e)
 {
@@ -925,6 +954,7 @@ void elv_unregister_queue(struct request_queue *q)
        if (q)
                __elv_unregister_queue(q->elevator);
 }
+EXPORT_SYMBOL(elv_unregister_queue);
 
 void elv_register(struct elevator_type *e)
 {
@@ -1050,10 +1080,11 @@ ssize_t elv_iosched_store(struct request_queue *q, const char *name,
        char elevator_name[ELV_NAME_MAX];
        struct elevator_type *e;
 
-       strlcpy(elevator_name, name, sizeof(elevator_name));
-       strstrip(elevator_name);
+       if (!q->elevator)
+               return count;
 
-       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;
@@ -1073,10 +1104,15 @@ ssize_t elv_iosched_store(struct request_queue *q, const char *name,
 ssize_t elv_iosched_show(struct request_queue *q, char *name)
 {
        struct elevator_queue *e = q->elevator;
-       struct elevator_type *elv = e->elevator_type;
+       struct elevator_type *elv;
        struct elevator_type *__e;
        int len = 0;
 
+       if (!q->elevator || !blk_queue_stackable(q))
+               return sprintf(name, "none\n");
+
+       elv = e->elevator_type;
+
        spin_lock(&elv_list_lock);
        list_for_each_entry(__e, &elv_list, list) {
                if (!strcmp(elv->elevator_name, __e->elevator_name))