[PATCH] elevator_t lifetime rules and sysfs fixes
diff --git a/block/as-iosched.c b/block/as-iosched.c
index 55a997f..3fb60eb 100644
--- a/block/as-iosched.c
+++ b/block/as-iosched.c
@@ -1709,11 +1709,6 @@
/*
* 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 @@
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 @@
}
#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 @@
#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 @@
&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 @@
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 @@
.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 d1f2ae1..6dc156e 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -2275,11 +2275,6 @@
/*
* 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 @@
}
#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 @@
#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_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 @@
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 @@
.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 27e494b..a3e3ff1 100644
--- a/block/deadline-iosched.c
+++ b/block/deadline-iosched.c
@@ -694,11 +694,6 @@
/*
* 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 @@
}
#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 @@
#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_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 @@
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 @@
.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 0232df2..0d2db53 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -120,15 +120,10 @@
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 @@
__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 @@
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 @@
}
}
+#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 = 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;
+}
+
+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;
+
+ if (!entry->store)
+ return -EIO;
+
+ 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 = kobject_get(&q->kobj);
- if (!e->kobj.parent)
- return -EBUSY;
+ e->kobj.parent = &q->kobj;
- snprintf(e->kobj.name, KOBJ_NAME_LEN, "%s", "iosched");
- e->kobj.ktype = e->elevator_type->elevator_ktype;
-
- return kobject_register(&e->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 @@
* 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 @@
/*
* 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 @@
*/
elevator_exit(old_elevator);
clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
- return;
+ return 1;
fail_register:
/*
@@ -761,10 +831,9 @@
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 @@
return count;
}
- elevator_switch(q, e);
+ if (!elevator_switch(q, e))
+ printk(KERN_ERR "elevator: switch to %s failed\n",elevator_name);
return count;
}
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index f65766e..4d0a80f 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -61,7 +61,7 @@
struct list_head list;
struct elevator_ops ops;
struct elevator_type *elevator_type;
- struct kobj_type *elevator_ktype;
+ struct attribute **elevator_attrs;
char elevator_name[ELV_NAME_MAX];
struct module *elevator_owner;
};
@@ -75,6 +75,7 @@
void *elevator_data;
struct kobject kobj;
struct elevator_type *elevator_type;
+ struct mutex sysfs_lock;
};
/*
@@ -141,6 +142,12 @@
ELV_MQUEUE_MUST,
};
+struct elv_fs_entry {
+ struct attribute attr;
+ ssize_t (*show)(elevator_t *, char *);
+ ssize_t (*store)(elevator_t *, const char *, size_t);
+};
+
#define rq_end_sector(rq) ((rq)->sector + (rq)->nr_sectors)
#endif