diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/as-iosched.c | 69 | ||||
| -rw-r--r-- | block/cfq-iosched.c | 74 | ||||
| -rw-r--r-- | block/deadline-iosched.c | 64 | ||||
| -rw-r--r-- | block/elevator.c | 146 |
4 files changed, 152 insertions, 201 deletions
diff --git a/block/as-iosched.c b/block/as-iosched.c index 55a997fc4bb..3fb60eb7093 100644 --- a/block/as-iosched.c +++ b/block/as-iosched.c @@ -1709,11 +1709,6 @@ static int as_init_queue(request_queue_t *q, elevator_t *e) /* * sysfs parts below */ -struct as_fs_entry { - struct attribute attr; - ssize_t (*show)(struct as_data *, char *); - ssize_t (*store)(struct as_data *, const char *, size_t); -}; static ssize_t as_var_show(unsigned int var, char *page) @@ -1730,8 +1725,9 @@ as_var_store(unsigned long *var, const char *page, size_t count) return count; } -static ssize_t as_est_show(struct as_data *ad, char *page) +static ssize_t as_est_show(elevator_t *e, char *page) { + struct as_data *ad = e->elevator_data; int pos = 0; pos += sprintf(page+pos, "%lu %% exit probability\n", @@ -1747,8 +1743,9 @@ static ssize_t as_est_show(struct as_data *ad, char *page) } #define SHOW_FUNCTION(__FUNC, __VAR) \ -static ssize_t __FUNC(struct as_data *ad, char *page) \ +static ssize_t __FUNC(elevator_t *e, char *page) \ { \ + struct as_data *ad = e->elevator_data; \ return as_var_show(jiffies_to_msecs((__VAR)), (page)); \ } SHOW_FUNCTION(as_readexpire_show, ad->fifo_expire[REQ_SYNC]); @@ -1759,9 +1756,10 @@ SHOW_FUNCTION(as_write_batchexpire_show, ad->batch_expire[REQ_ASYNC]); #undef SHOW_FUNCTION #define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX) \ -static ssize_t __FUNC(struct as_data *ad, const char *page, size_t count) \ +static ssize_t __FUNC(elevator_t *e, const char *page, size_t count) \ { \ - int ret = as_var_store(__PTR, (page), count); \ + struct as_data *ad = e->elevator_data; \ + int ret = as_var_store(__PTR, (page), count); \ if (*(__PTR) < (MIN)) \ *(__PTR) = (MIN); \ else if (*(__PTR) > (MAX)) \ @@ -1778,37 +1776,37 @@ STORE_FUNCTION(as_write_batchexpire_store, &ad->batch_expire[REQ_ASYNC], 0, INT_MAX); #undef STORE_FUNCTION -static struct as_fs_entry as_est_entry = { +static struct elv_fs_entry as_est_entry = { .attr = {.name = "est_time", .mode = S_IRUGO }, .show = as_est_show, }; -static struct as_fs_entry as_readexpire_entry = { +static struct elv_fs_entry as_readexpire_entry = { .attr = {.name = "read_expire", .mode = S_IRUGO | S_IWUSR }, .show = as_readexpire_show, .store = as_readexpire_store, }; -static struct as_fs_entry as_writeexpire_entry = { +static struct elv_fs_entry as_writeexpire_entry = { .attr = {.name = "write_expire", .mode = S_IRUGO | S_IWUSR }, .show = as_writeexpire_show, .store = as_writeexpire_store, }; -static struct as_fs_entry as_anticexpire_entry = { +static struct elv_fs_entry as_anticexpire_entry = { .attr = {.name = "antic_expire", .mode = S_IRUGO | S_IWUSR }, .show = as_anticexpire_show, .store = as_anticexpire_store, }; -static struct as_fs_entry as_read_batchexpire_entry = { +static struct elv_fs_entry as_read_batchexpire_entry = { .attr = {.name = "read_batch_expire", .mode = S_IRUGO | S_IWUSR }, .show = as_read_batchexpire_show, .store = as_read_batchexpire_store, }; -static struct as_fs_entry as_write_batchexpire_entry = { +static struct elv_fs_entry as_write_batchexpire_entry = { .attr = {.name = "write_batch_expire", .mode = S_IRUGO | S_IWUSR }, .show = as_write_batchexpire_show, .store = as_write_batchexpire_store, }; -static struct attribute *default_attrs[] = { +static struct attribute *as_attrs[] = { &as_est_entry.attr, &as_readexpire_entry.attr, &as_writeexpire_entry.attr, @@ -1818,43 +1816,6 @@ static struct attribute *default_attrs[] = { NULL, }; -#define to_as(atr) container_of((atr), struct as_fs_entry, attr) - -static ssize_t -as_attr_show(struct kobject *kobj, struct attribute *attr, char *page) -{ - elevator_t *e = container_of(kobj, elevator_t, kobj); - struct as_fs_entry *entry = to_as(attr); - - if (!entry->show) - return -EIO; - - return entry->show(e->elevator_data, page); -} - -static ssize_t -as_attr_store(struct kobject *kobj, struct attribute *attr, - const char *page, size_t length) -{ - elevator_t *e = container_of(kobj, elevator_t, kobj); - struct as_fs_entry *entry = to_as(attr); - - if (!entry->store) - return -EIO; - - return entry->store(e->elevator_data, page, length); -} - -static struct sysfs_ops as_sysfs_ops = { - .show = as_attr_show, - .store = as_attr_store, -}; - -static struct kobj_type as_ktype = { - .sysfs_ops = &as_sysfs_ops, - .default_attrs = default_attrs, -}; - static struct elevator_type iosched_as = { .ops = { .elevator_merge_fn = as_merge, @@ -1876,7 +1837,7 @@ static struct elevator_type iosched_as = { .trim = as_trim, }, - .elevator_ktype = &as_ktype, + .elevator_attrs = as_attrs, .elevator_name = "anticipatory", .elevator_owner = THIS_MODULE, }; diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index d1f2ae1629f..6dc156e1c29 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -2275,11 +2275,6 @@ fail: /* * sysfs parts below --> */ -struct cfq_fs_entry { - struct attribute attr; - ssize_t (*show)(struct cfq_data *, char *); - ssize_t (*store)(struct cfq_data *, const char *, size_t); -}; static ssize_t cfq_var_show(unsigned int var, char *page) @@ -2297,8 +2292,9 @@ cfq_var_store(unsigned int *var, const char *page, size_t count) } #define SHOW_FUNCTION(__FUNC, __VAR, __CONV) \ -static ssize_t __FUNC(struct cfq_data *cfqd, char *page) \ +static ssize_t __FUNC(elevator_t *e, char *page) \ { \ + struct cfq_data *cfqd = e->elevator_data; \ unsigned int __data = __VAR; \ if (__CONV) \ __data = jiffies_to_msecs(__data); \ @@ -2318,8 +2314,9 @@ SHOW_FUNCTION(cfq_max_depth_show, cfqd->cfq_max_depth, 0); #undef SHOW_FUNCTION #define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV) \ -static ssize_t __FUNC(struct cfq_data *cfqd, const char *page, size_t count) \ +static ssize_t __FUNC(elevator_t *e, const char *page, size_t count) \ { \ + struct cfq_data *cfqd = e->elevator_data; \ unsigned int __data; \ int ret = cfq_var_store(&__data, (page), count); \ if (__data < (MIN)) \ @@ -2345,63 +2342,63 @@ STORE_FUNCTION(cfq_slice_async_rq_store, &cfqd->cfq_slice_async_rq, 1, UINT_MAX, STORE_FUNCTION(cfq_max_depth_store, &cfqd->cfq_max_depth, 1, UINT_MAX, 0); #undef STORE_FUNCTION -static struct cfq_fs_entry cfq_quantum_entry = { +static struct elv_fs_entry cfq_quantum_entry = { .attr = {.name = "quantum", .mode = S_IRUGO | S_IWUSR }, .show = cfq_quantum_show, .store = cfq_quantum_store, }; -static struct cfq_fs_entry cfq_queued_entry = { +static struct elv_fs_entry cfq_queued_entry = { .attr = {.name = "queued", .mode = S_IRUGO | S_IWUSR }, .show = cfq_queued_show, .store = cfq_queued_store, }; -static struct cfq_fs_entry cfq_fifo_expire_sync_entry = { +static struct elv_fs_entry cfq_fifo_expire_sync_entry = { .attr = {.name = "fifo_expire_sync", .mode = S_IRUGO | S_IWUSR }, .show = cfq_fifo_expire_sync_show, .store = cfq_fifo_expire_sync_store, }; -static struct cfq_fs_entry cfq_fifo_expire_async_entry = { +static struct elv_fs_entry cfq_fifo_expire_async_entry = { .attr = {.name = "fifo_expire_async", .mode = S_IRUGO | S_IWUSR }, .show = cfq_fifo_expire_async_show, .store = cfq_fifo_expire_async_store, }; -static struct cfq_fs_entry cfq_back_max_entry = { +static struct elv_fs_entry cfq_back_max_entry = { .attr = {.name = "back_seek_max", .mode = S_IRUGO | S_IWUSR }, .show = cfq_back_max_show, .store = cfq_back_max_store, }; -static struct cfq_fs_entry cfq_back_penalty_entry = { +static struct elv_fs_entry cfq_back_penalty_entry = { .attr = {.name = "back_seek_penalty", .mode = S_IRUGO | S_IWUSR }, .show = cfq_back_penalty_show, .store = cfq_back_penalty_store, }; -static struct cfq_fs_entry cfq_slice_sync_entry = { +static struct elv_fs_entry cfq_slice_sync_entry = { .attr = {.name = "slice_sync", .mode = S_IRUGO | S_IWUSR }, .show = cfq_slice_sync_show, .store = cfq_slice_sync_store, }; -static struct cfq_fs_entry cfq_slice_async_entry = { +static struct elv_fs_entry cfq_slice_async_entry = { .attr = {.name = "slice_async", .mode = S_IRUGO | S_IWUSR }, .show = cfq_slice_async_show, .store = cfq_slice_async_store, }; -static struct cfq_fs_entry cfq_slice_async_rq_entry = { +static struct elv_fs_entry cfq_slice_async_rq_entry = { .attr = {.name = "slice_async_rq", .mode = S_IRUGO | S_IWUSR }, .show = cfq_slice_async_rq_show, .store = cfq_slice_async_rq_store, }; -static struct cfq_fs_entry cfq_slice_idle_entry = { +static struct elv_fs_entry cfq_slice_idle_entry = { .attr = {.name = "slice_idle", .mode = S_IRUGO | S_IWUSR }, .show = cfq_slice_idle_show, .store = cfq_slice_idle_store, }; -static struct cfq_fs_entry cfq_max_depth_entry = { +static struct elv_fs_entry cfq_max_depth_entry = { .attr = {.name = "max_depth", .mode = S_IRUGO | S_IWUSR }, .show = cfq_max_depth_show, .store = cfq_max_depth_store, }; -static struct attribute *default_attrs[] = { +static struct attribute *cfq_attrs[] = { &cfq_quantum_entry.attr, &cfq_queued_entry.attr, &cfq_fifo_expire_sync_entry.attr, @@ -2416,43 +2413,6 @@ static struct attribute *default_attrs[] = { NULL, }; -#define to_cfq(atr) container_of((atr), struct cfq_fs_entry, attr) - -static ssize_t -cfq_attr_show(struct kobject *kobj, struct attribute *attr, char *page) -{ - elevator_t *e = container_of(kobj, elevator_t, kobj); - struct cfq_fs_entry *entry = to_cfq(attr); - - if (!entry->show) - return -EIO; - - return entry->show(e->elevator_data, page); -} - -static ssize_t -cfq_attr_store(struct kobject *kobj, struct attribute *attr, - const char *page, size_t length) -{ - elevator_t *e = container_of(kobj, elevator_t, kobj); - struct cfq_fs_entry *entry = to_cfq(attr); - - if (!entry->store) - return -EIO; - - return entry->store(e->elevator_data, page, length); -} - -static struct sysfs_ops cfq_sysfs_ops = { - .show = cfq_attr_show, - .store = cfq_attr_store, -}; - -static struct kobj_type cfq_ktype = { - .sysfs_ops = &cfq_sysfs_ops, - .default_attrs = default_attrs, -}; - static struct elevator_type iosched_cfq = { .ops = { .elevator_merge_fn = cfq_merge, @@ -2473,7 +2433,7 @@ static struct elevator_type iosched_cfq = { .elevator_exit_fn = cfq_exit_queue, .trim = cfq_trim, }, - .elevator_ktype = &cfq_ktype, + .elevator_attrs = cfq_attrs, .elevator_name = "cfq", .elevator_owner = THIS_MODULE, }; diff --git a/block/deadline-iosched.c b/block/deadline-iosched.c index 27e494b1bf9..a3e3ff1e0c6 100644 --- a/block/deadline-iosched.c +++ b/block/deadline-iosched.c @@ -694,11 +694,6 @@ deadline_set_request(request_queue_t *q, struct request *rq, struct bio *bio, /* * sysfs parts below */ -struct deadline_fs_entry { - struct attribute attr; - ssize_t (*show)(struct deadline_data *, char *); - ssize_t (*store)(struct deadline_data *, const char *, size_t); -}; static ssize_t deadline_var_show(int var, char *page) @@ -716,9 +711,10 @@ deadline_var_store(int *var, const char *page, size_t count) } #define SHOW_FUNCTION(__FUNC, __VAR, __CONV) \ -static ssize_t __FUNC(struct deadline_data *dd, char *page) \ +static ssize_t __FUNC(elevator_t *e, char *page) \ { \ - int __data = __VAR; \ + struct deadline_data *dd = e->elevator_data; \ + int __data = __VAR; \ if (__CONV) \ __data = jiffies_to_msecs(__data); \ return deadline_var_show(__data, (page)); \ @@ -731,8 +727,9 @@ SHOW_FUNCTION(deadline_fifobatch_show, dd->fifo_batch, 0); #undef SHOW_FUNCTION #define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV) \ -static ssize_t __FUNC(struct deadline_data *dd, const char *page, size_t count) \ +static ssize_t __FUNC(elevator_t *e, const char *page, size_t count) \ { \ + struct deadline_data *dd = e->elevator_data; \ int __data; \ int ret = deadline_var_store(&__data, (page), count); \ if (__data < (MIN)) \ @@ -752,33 +749,33 @@ STORE_FUNCTION(deadline_frontmerges_store, &dd->front_merges, 0, 1, 0); STORE_FUNCTION(deadline_fifobatch_store, &dd->fifo_batch, 0, INT_MAX, 0); #undef STORE_FUNCTION -static struct deadline_fs_entry deadline_readexpire_entry = { +static struct elv_fs_entry deadline_readexpire_entry = { .attr = {.name = "read_expire", .mode = S_IRUGO | S_IWUSR }, .show = deadline_readexpire_show, .store = deadline_readexpire_store, }; -static struct deadline_fs_entry deadline_writeexpire_entry = { +static struct elv_fs_entry deadline_writeexpire_entry = { .attr = {.name = "write_expire", .mode = S_IRUGO | S_IWUSR }, .show = deadline_writeexpire_show, .store = deadline_writeexpire_store, }; -static struct deadline_fs_entry deadline_writesstarved_entry = { +static struct elv_fs_entry deadline_writesstarved_entry = { .attr = {.name = "writes_starved", .mode = S_IRUGO | S_IWUSR }, .show = deadline_writesstarved_show, .store = deadline_writesstarved_store, }; -static struct deadline_fs_entry deadline_frontmerges_entry = { +static struct elv_fs_entry deadline_frontmerges_entry = { .attr = {.name = "front_merges", .mode = S_IRUGO | S_IWUSR }, .show = deadline_frontmerges_show, .store = deadline_frontmerges_store, }; -static struct deadline_fs_entry deadline_fifobatch_entry = { +static struct elv_fs_entry deadline_fifobatch_entry = { .attr = {.name = "fifo_batch", .mode = S_IRUGO | S_IWUSR }, .show = deadline_fifobatch_show, .store = deadline_fifobatch_store, }; -static struct attribute *default_attrs[] = { +static struct attribute *deadline_attrs[] = { &deadline_readexpire_entry.attr, &deadline_writeexpire_entry.attr, &deadline_writesstarved_entry.attr, @@ -787,43 +784,6 @@ static struct attribute *default_attrs[] = { NULL, }; -#define to_deadline(atr) container_of((atr), struct deadline_fs_entry, attr) - -static ssize_t -deadline_attr_show(struct kobject *kobj, struct attribute *attr, char *page) -{ - elevator_t *e = container_of(kobj, elevator_t, kobj); - struct deadline_fs_entry *entry = to_deadline(attr); - - if (!entry->show) - return -EIO; - - return entry->show(e->elevator_data, page); -} - -static ssize_t -deadline_attr_store(struct kobject *kobj, struct attribute *attr, - const char *page, size_t length) -{ - elevator_t *e = container_of(kobj, elevator_t, kobj); - struct deadline_fs_entry *entry = to_deadline(attr); - - if (!entry->store) - return -EIO; - - return entry->store(e->elevator_data, page, length); -} - -static struct sysfs_ops deadline_sysfs_ops = { - .show = deadline_attr_show, - .store = deadline_attr_store, -}; - -static struct kobj_type deadline_ktype = { - .sysfs_ops = &deadline_sysfs_ops, - .default_attrs = default_attrs, -}; - static struct elevator_type iosched_deadline = { .ops = { .elevator_merge_fn = deadline_merge, @@ -840,7 +800,7 @@ static struct elevator_type iosched_deadline = { .elevator_exit_fn = deadline_exit_queue, }, - .elevator_ktype = &deadline_ktype, + .elevator_attrs = deadline_attrs, .elevator_name = "deadline", .elevator_owner = THIS_MODULE, }; diff --git a/block/elevator.c b/block/elevator.c index 0232df2b16e..0d2db536c6a 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -120,15 +120,10 @@ static struct elevator_type *elevator_get(const char *name) return e; } -static int elevator_attach(request_queue_t *q, struct elevator_type *e, - struct elevator_queue *eq) +static int elevator_attach(request_queue_t *q, struct elevator_queue *eq) { int ret = 0; - memset(eq, 0, sizeof(*eq)); - eq->ops = &e->ops; - eq->elevator_type = e; - q->elevator = eq; if (eq->ops->elevator_init_fn) @@ -154,6 +149,32 @@ static int __init elevator_setup(char *str) __setup("elevator=", elevator_setup); +static struct kobj_type elv_ktype; + +static elevator_t *elevator_alloc(struct elevator_type *e) +{ + elevator_t *eq = kmalloc(sizeof(elevator_t), GFP_KERNEL); + if (eq) { + 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; + mutex_init(&eq->sysfs_lock); + } else { + elevator_put(e); + } + return eq; +} + +static void elevator_release(struct kobject *kobj) +{ + elevator_t *e = container_of(kobj, elevator_t, kobj); + elevator_put(e->elevator_type); + kfree(e); +} + int elevator_init(request_queue_t *q, char *name) { struct elevator_type *e = NULL; @@ -176,29 +197,26 @@ int elevator_init(request_queue_t *q, char *name) e = elevator_get("noop"); } - eq = kmalloc(sizeof(struct elevator_queue), GFP_KERNEL); - if (!eq) { - elevator_put(e); + eq = elevator_alloc(e); + if (!eq) return -ENOMEM; - } - ret = elevator_attach(q, e, eq); - if (ret) { - kfree(eq); - elevator_put(e); - } + ret = elevator_attach(q, eq); + if (ret) + kobject_put(&eq->kobj); return ret; } void elevator_exit(elevator_t *e) { + mutex_lock(&e->sysfs_lock); if (e->ops->elevator_exit_fn) e->ops->elevator_exit_fn(e); + e->ops = NULL; + mutex_unlock(&e->sysfs_lock); - elevator_put(e->elevator_type); - e->elevator_type = NULL; - kfree(e); + kobject_put(&e->kobj); } /* @@ -627,26 +645,78 @@ void elv_completed_request(request_queue_t *q, struct request *rq) } } -int elv_register_queue(struct request_queue *q) +#define to_elv(atr) container_of((atr), struct elv_fs_entry, attr) + +static ssize_t +elv_attr_show(struct kobject *kobj, struct attribute *attr, char *page) { - elevator_t *e = q->elevator; + elevator_t *e = container_of(kobj, elevator_t, kobj); + struct elv_fs_entry *entry = to_elv(attr); + ssize_t error; + + if (!entry->show) + return -EIO; + + mutex_lock(&e->sysfs_lock); + error = e->ops ? entry->show(e, page) : -ENOENT; + mutex_unlock(&e->sysfs_lock); + return error; +} - e->kobj.parent = kobject_get(&q->kobj); - if (!e->kobj.parent) - return -EBUSY; +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); + ssize_t error; - snprintf(e->kobj.name, KOBJ_NAME_LEN, "%s", "iosched"); - e->kobj.ktype = e->elevator_type->elevator_ktype; + if (!entry->store) + return -EIO; - return kobject_register(&e->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 = { + .show = elv_attr_show, + .store = elv_attr_store, +}; + +static struct kobj_type elv_ktype = { + .sysfs_ops = &elv_sysfs_ops, + .release = elevator_release, +}; + +int elv_register_queue(struct request_queue *q) +{ + elevator_t *e = q->elevator; + int error; + + e->kobj.parent = &q->kobj; + + error = kobject_add(&e->kobj); + if (!error) { + struct attribute **attr = e->elevator_type->elevator_attrs; + if (attr) { + while (*attr) { + if (sysfs_create_file(&e->kobj,*attr++)) + break; + } + } + kobject_uevent(&e->kobj, KOBJ_ADD); + } + return error; } void elv_unregister_queue(struct request_queue *q) { if (q) { elevator_t *e = q->elevator; - kobject_unregister(&e->kobj); - kobject_put(&q->kobj); + kobject_uevent(&e->kobj, KOBJ_REMOVE); + kobject_del(&e->kobj); } } @@ -697,16 +767,16 @@ 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 void elevator_switch(request_queue_t *q, struct elevator_type *new_e) +static int elevator_switch(request_queue_t *q, struct elevator_type *new_e) { elevator_t *old_elevator, *e; /* * Allocate new elevator */ - e = kmalloc(sizeof(elevator_t), GFP_KERNEL); + e = elevator_alloc(new_e); if (!e) - goto error; + return 0; /* * Turn on BYPASS and drain all requests w/ elevator private data @@ -737,7 +807,7 @@ static void elevator_switch(request_queue_t *q, struct elevator_type *new_e) /* * attach and start new elevator */ - if (elevator_attach(q, new_e, e)) + if (elevator_attach(q, e)) goto fail; if (elv_register_queue(q)) @@ -748,7 +818,7 @@ static void elevator_switch(request_queue_t *q, struct elevator_type *new_e) */ elevator_exit(old_elevator); clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags); - return; + return 1; fail_register: /* @@ -761,10 +831,9 @@ fail: q->elevator = old_elevator; elv_register_queue(q); clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags); - kfree(e); -error: - elevator_put(new_e); - printk(KERN_ERR "elevator: switch to %s failed\n",new_e->elevator_name); + if (e) + kobject_put(&e->kobj); + return 0; } ssize_t elv_iosched_store(request_queue_t *q, const char *name, size_t count) @@ -791,7 +860,8 @@ ssize_t elv_iosched_store(request_queue_t *q, const char *name, size_t count) return count; } - elevator_switch(q, e); + if (!elevator_switch(q, e)) + printk(KERN_ERR "elevator: switch to %s failed\n",elevator_name); return count; } |