nfsd: nfsd should drop CAP_MKNOD for non-root
[safe/jmp/linux-2.6] / block / elevator.c
index e643291..98259ed 100644 (file)
@@ -3,7 +3,7 @@
  *
  *  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/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.
+ */
+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_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))
                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);
 
@@ -93,21 +131,14 @@ static inline int elv_try_merge(struct request *__rq, struct bio *bio)
 
 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)
@@ -119,23 +150,39 @@ static struct elevator_type *elevator_get(const char *name)
 {
        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);
+
+               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;
 
-       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;
@@ -161,21 +208,19 @@ __setup("elevator=", elevator_setup);
 
 static struct kobj_type elv_ktype;
 
-static elevator_t *elevator_alloc(request_queue_t *q, 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_node(sizeof(elevator_t), GFP_KERNEL, q->node);
+       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_node(sizeof(struct hlist_head) * ELV_HASH_ENTRIES,
@@ -195,14 +240,15 @@ 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;
@@ -214,15 +260,27 @@ int elevator_init(request_queue_t *q, char *name)
        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);
@@ -238,10 +296,9 @@ int elevator_init(request_queue_t *q, char *name)
        elevator_attach(q, eq, data);
        return ret;
 }
-
 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)
@@ -251,37 +308,52 @@ 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)
+{
+       struct elevator_queue *e = q->elevator;
+
+       if (e->ops->elevator_activate_req_fn)
+               e->ops->elevator_activate_req_fn(q, rq);
+}
+
+static void elv_deactivate_rq(struct request_queue *q, struct request *rq)
+{
+       struct elevator_queue *e = q->elevator;
+
+       if (e->ops->elevator_deactivate_req_fn)
+               e->ops->elevator_deactivate_req_fn(q, rq);
+}
+
 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;
@@ -327,7 +399,6 @@ struct request *elv_rb_add(struct rb_root *root, 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)
@@ -336,7 +407,6 @@ 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)
@@ -357,18 +427,18 @@ struct request *elv_rb_find(struct rb_root *root, sector_t sector)
 
        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;
@@ -378,11 +448,15 @@ void elv_dispatch_sort(request_queue_t *q, struct request *rq)
        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 (blk_discard_rq(rq) != blk_discard_rq(pos))
+                       break;
+               if (rq_data_dir(rq) != rq_data_dir(pos))
+                       break;
+               if (pos->cmd_flags & stop_flags)
                        break;
                if (rq->sector >= boundary) {
                        if (pos->sector < boundary)
@@ -397,7 +471,6 @@ void elv_dispatch_sort(request_queue_t *q, struct request *rq)
 
        list_add(&rq->queuelist, entry);
 }
-
 EXPORT_SYMBOL(elv_dispatch_sort);
 
 /*
@@ -418,12 +491,11 @@ void elv_dispatch_add_tail(struct request_queue *q, struct request *rq)
        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;
 
@@ -438,6 +510,9 @@ int elv_merge(request_queue_t *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.
         */
@@ -453,9 +528,9 @@ int elv_merge(request_queue_t *q, struct request **req, struct bio *bio)
        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);
@@ -466,10 +541,10 @@ void elv_merged_request(request_queue_t *q, struct request *rq, int 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);
@@ -481,18 +556,16 @@ void elv_merge_requests(request_queue_t *q, struct request *rq,
        q->last_merge = rq;
 }
 
-void elv_requeue_request(request_queue_t *q, struct request *rq)
+void elv_requeue_request(struct request_queue *q, struct request *rq)
 {
-       elevator_t *e = q->elevator;
-
        /*
         * 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);
+               if (blk_sorted_rq(rq))
+                       elv_deactivate_rq(q, rq);
        }
 
        rq->cmd_flags &= ~REQ_STARTED;
@@ -500,7 +573,7 @@ void elv_requeue_request(request_queue_t *q, struct request *rq)
        elv_insert(q, rq, ELEVATOR_INSERT_REQUEUE);
 }
 
-static void elv_drain_elevator(request_queue_t *q)
+static void elv_drain_elevator(struct request_queue *q)
 {
        static int printed;
        while (q->elevator->ops->elevator_dispatch_fn(q, 1))
@@ -514,13 +587,13 @@ static void elv_drain_elevator(request_queue_t *q)
        }
 }
 
-void elv_insert(request_queue_t *q, struct request *rq, int where)
+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;
 
@@ -546,11 +619,11 @@ void elv_insert(request_queue_t *q, struct request *rq, int where)
                 *   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)) {
@@ -575,6 +648,12 @@ void elv_insert(request_queue_t *q, struct request *rq, int where)
                 */
                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;
@@ -589,16 +668,11 @@ void elv_insert(request_queue_t *q, struct request *rq, int where)
                }
 
                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();
        }
 
@@ -611,7 +685,7 @@ void elv_insert(request_queue_t *q, struct request *rq, int where)
        }
 }
 
-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)
@@ -634,11 +708,12 @@ void __elv_add_request(request_queue_t *q, struct request *rq, int where,
                 * 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)
@@ -646,10 +721,9 @@ void __elv_add_request(request_queue_t *q, struct request *rq, int where,
 
        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;
@@ -658,10 +732,9 @@ void elv_add_request(request_queue_t *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(request_queue_t *q)
+static inline struct request *__elv_next_request(struct request_queue *q)
 {
        struct request *rq;
 
@@ -677,23 +750,20 @@ static inline struct request *__elv_next_request(request_queue_t *q)
        }
 }
 
-struct request *elv_next_request(request_queue_t *q)
+struct request *elv_next_request(struct request_queue *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);
+                       if (blk_sorted_rq(rq))
+                               elv_activate_rq(q, rq);
 
                        /*
                         * just mark as started even if we don't start
@@ -701,7 +771,7 @@ struct request *elv_next_request(request_queue_t *q)
                         * 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) {
@@ -709,7 +779,20 @@ struct request *elv_next_request(request_queue_t *q)
                        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);
@@ -722,31 +805,31 @@ struct request *elv_next_request(request_queue_t *q)
                         * 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) {
-                       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);
+                       __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(request_queue_t *q, struct request *rq)
+void elv_dequeue_request(struct request_queue *q, struct request *rq)
 {
        BUG_ON(list_empty(&rq->queuelist));
        BUG_ON(ELV_ON_HASH(rq));
@@ -762,11 +845,9 @@ void elv_dequeue_request(request_queue_t *q, struct request *rq)
                q->in_flight++;
 }
 
-EXPORT_SYMBOL(elv_dequeue_request);
-
-int elv_queue_empty(request_queue_t *q)
+int elv_queue_empty(struct request_queue *q)
 {
-       elevator_t *e = q->elevator;
+       struct elevator_queue *e = q->elevator;
 
        if (!list_empty(&q->queue_head))
                return 0;
@@ -776,30 +857,29 @@ int elv_queue_empty(request_queue_t *q)
 
        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, 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, gfp_mask);
@@ -808,17 +888,17 @@ int elv_set_request(request_queue_t *q, struct request *rq, gfp_t gfp_mask)
        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)
+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);
@@ -826,9 +906,22 @@ int elv_may_queue(request_queue_t *q, int rw)
        return ELV_MQUEUE_MAY;
 }
 
-void elv_completed_request(request_queue_t *q, struct request *rq)
+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;
+       struct elevator_queue *e = q->elevator;
 
        /*
         * request is released from the driver, io must be done
@@ -844,12 +937,16 @@ void elv_completed_request(request_queue_t *q, struct request *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 (!q->in_flight &&
                    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_start_queueing(q);
                }
        }
 }
@@ -859,13 +956,14 @@ void elv_completed_request(request_queue_t *q, struct request *rq)
 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);
@@ -876,13 +974,14 @@ static ssize_t
 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);
@@ -901,12 +1000,10 @@ static struct kobj_type elv_ktype = {
 
 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) {
@@ -921,7 +1018,7 @@ int elv_register_queue(struct request_queue *q)
        return error;
 }
 
-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);
@@ -933,20 +1030,22 @@ void elv_unregister_queue(struct request_queue *q)
                __elv_unregister_queue(q->elevator);
 }
 
-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);
 
@@ -968,9 +1067,9 @@ void elv_unregister(struct elevator_type *e)
                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);
 
@@ -980,9 +1079,9 @@ 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;
 
        /*
@@ -1003,13 +1102,12 @@ static int elevator_switch(request_queue_t *q, struct elevator_type *new_e)
         */
        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);
@@ -1037,7 +1135,12 @@ static int elevator_switch(request_queue_t *q, struct elevator_type *new_e)
         * 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:
@@ -1048,22 +1151,22 @@ 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;
 }
 
-ssize_t elv_iosched_store(request_queue_t *q, const char *name, size_t count)
+ssize_t elv_iosched_store(struct request_queue *q, const char *name,
+                         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) {
@@ -1077,34 +1180,33 @@ ssize_t elv_iosched_store(request_queue_t *q, const char *name, size_t count)
        }
 
        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;
 }
 
-ssize_t elv_iosched_show(request_queue_t *q, char *name)
+ssize_t elv_iosched_show(struct request_queue *q, char *name)
 {
-       elevator_t *e = q->elevator;
+       struct elevator_queue *e = q->elevator;
        struct elevator_type *elv = e->elevator_type;
-       struct list_head *entry;
+       struct elevator_type *__e;
        int len = 0;
 
-       spin_lock_irq(q->queue_lock);
-       list_for_each(entry, &elv_list) {
-               struct elevator_type *__e;
-
-               __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);
 
@@ -1113,10 +1215,10 @@ struct request *elv_rb_former_request(request_queue_t *q, struct request *rq)
 
        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);
 
@@ -1125,5 +1227,4 @@ struct request *elv_rb_latter_request(request_queue_t *q, struct request *rq)
 
        return NULL;
 }
-
 EXPORT_SYMBOL(elv_rb_latter_request);