diff options
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/base.h | 12 | ||||
| -rw-r--r-- | drivers/base/bus.c | 66 | ||||
| -rw-r--r-- | drivers/base/class.c | 14 | ||||
| -rw-r--r-- | drivers/base/component.c | 14 | ||||
| -rw-r--r-- | drivers/base/core.c | 246 | ||||
| -rw-r--r-- | drivers/base/cpu.c | 1 | ||||
| -rw-r--r-- | drivers/base/dd.c | 188 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/Makefile | 4 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/builtin/.gitignore | 1 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/builtin/Makefile | 40 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/fallback_table.c | 5 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/main.c | 8 | ||||
| -rw-r--r-- | drivers/base/platform.c | 21 | ||||
| -rw-r--r-- | drivers/base/power/main.c | 12 | ||||
| -rw-r--r-- | drivers/base/power/runtime.c | 101 | ||||
| -rw-r--r-- | drivers/base/test/test_async_driver_probe.c | 261 |
16 files changed, 752 insertions, 242 deletions
diff --git a/drivers/base/base.h b/drivers/base/base.h index 7a419a7a6235..b405436ee28e 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -60,12 +60,17 @@ struct driver_private { * @knode_parent - node in sibling list * @knode_driver - node in driver list * @knode_bus - node in bus list + * @knode_class - node in class list * @deferred_probe - entry in deferred_probe_list which is used to retry the * binding of drivers which were unable to get all the resources needed by * the device; typically because it depends on another driver getting * probed first. + * @async_driver - pointer to device driver awaiting probe via async_probe * @device - pointer back to the struct device that this structure is * associated with. + * @dead - This device is currently either in the process of or has been + * removed from the system. Any asynchronous events scheduled for this + * device should exit without taking any action. * * Nothing outside of the driver core should ever touch these fields. */ @@ -74,8 +79,11 @@ struct device_private { struct klist_node knode_parent; struct klist_node knode_driver; struct klist_node knode_bus; + struct klist_node knode_class; struct list_head deferred_probe; + struct device_driver *async_driver; struct device *device; + u8 dead:1; }; #define to_device_private_parent(obj) \ container_of(obj, struct device_private, knode_parent) @@ -83,6 +91,8 @@ struct device_private { container_of(obj, struct device_private, knode_driver) #define to_device_private_bus(obj) \ container_of(obj, struct device_private, knode_bus) +#define to_device_private_class(obj) \ + container_of(obj, struct device_private, knode_class) /* initialisation functions */ extern int devices_init(void); @@ -124,6 +134,8 @@ extern int driver_add_groups(struct device_driver *drv, const struct attribute_group **groups); extern void driver_remove_groups(struct device_driver *drv, const struct attribute_group **groups); +int device_driver_attach(struct device_driver *drv, struct device *dev); +void device_driver_detach(struct device *dev); extern char *make_class_name(const char *name, struct kobject *kobj); diff --git a/drivers/base/bus.c b/drivers/base/bus.c index e06a57936cc9..0a58e969f8b7 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -187,11 +187,7 @@ static ssize_t unbind_store(struct device_driver *drv, const char *buf, dev = bus_find_device_by_name(bus, NULL, buf); if (dev && dev->driver == drv) { - if (dev->parent && dev->bus->need_parent_lock) - device_lock(dev->parent); - device_release_driver(dev); - if (dev->parent && dev->bus->need_parent_lock) - device_unlock(dev->parent); + device_driver_detach(dev); err = count; } put_device(dev); @@ -214,13 +210,7 @@ static ssize_t bind_store(struct device_driver *drv, const char *buf, dev = bus_find_device_by_name(bus, NULL, buf); if (dev && dev->driver == NULL && driver_match_device(drv, dev)) { - if (dev->parent && bus->need_parent_lock) - device_lock(dev->parent); - device_lock(dev); - err = driver_probe_device(drv, dev); - device_unlock(dev); - if (dev->parent && bus->need_parent_lock) - device_unlock(dev->parent); + err = device_driver_attach(drv, dev); if (err > 0) { /* success */ @@ -236,12 +226,12 @@ static ssize_t bind_store(struct device_driver *drv, const char *buf, } static DRIVER_ATTR_IGNORE_LOCKDEP(bind, S_IWUSR, NULL, bind_store); -static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf) +static ssize_t drivers_autoprobe_show(struct bus_type *bus, char *buf) { return sprintf(buf, "%d\n", bus->p->drivers_autoprobe); } -static ssize_t store_drivers_autoprobe(struct bus_type *bus, +static ssize_t drivers_autoprobe_store(struct bus_type *bus, const char *buf, size_t count) { if (buf[0] == '0') @@ -251,7 +241,7 @@ static ssize_t store_drivers_autoprobe(struct bus_type *bus, return count; } -static ssize_t store_drivers_probe(struct bus_type *bus, +static ssize_t drivers_probe_store(struct bus_type *bus, const char *buf, size_t count) { struct device *dev; @@ -586,9 +576,8 @@ static void remove_bind_files(struct device_driver *drv) driver_remove_file(drv, &driver_attr_unbind); } -static BUS_ATTR(drivers_probe, S_IWUSR, NULL, store_drivers_probe); -static BUS_ATTR(drivers_autoprobe, S_IWUSR | S_IRUGO, - show_drivers_autoprobe, store_drivers_autoprobe); +static BUS_ATTR_WO(drivers_probe); +static BUS_ATTR_RW(drivers_autoprobe); static int add_probe_files(struct bus_type *bus) { @@ -621,17 +610,6 @@ static ssize_t uevent_store(struct device_driver *drv, const char *buf, } static DRIVER_ATTR_WO(uevent); -static void driver_attach_async(void *_drv, async_cookie_t cookie) -{ - struct device_driver *drv = _drv; - int ret; - - ret = driver_attach(drv); - - pr_debug("bus: '%s': driver %s async attach completed: %d\n", - drv->bus->name, drv->name, ret); -} - /** * bus_add_driver - Add a driver to the bus. * @drv: driver. @@ -664,15 +642,9 @@ int bus_add_driver(struct device_driver *drv) klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers); if (drv->bus->p->drivers_autoprobe) { - if (driver_allows_async_probing(drv)) { - pr_debug("bus: '%s': probing driver %s asynchronously\n", - drv->bus->name, drv->name); - async_schedule(driver_attach_async, drv); - } else { - error = driver_attach(drv); - if (error) - goto out_unregister; - } + error = driver_attach(drv); + if (error) + goto out_unregister; } module_add_driver(drv->owner, drv); @@ -774,13 +746,8 @@ EXPORT_SYMBOL_GPL(bus_rescan_devices); */ int device_reprobe(struct device *dev) { - if (dev->driver) { - if (dev->parent && dev->bus->need_parent_lock) - device_lock(dev->parent); - device_release_driver(dev); - if (dev->parent && dev->bus->need_parent_lock) - device_unlock(dev->parent); - } + if (dev->driver) + device_driver_detach(dev); return bus_rescan_devices_helper(dev, NULL); } EXPORT_SYMBOL_GPL(device_reprobe); @@ -838,7 +805,14 @@ static ssize_t bus_uevent_store(struct bus_type *bus, rc = kobject_synth_uevent(&bus->p->subsys.kobj, buf, count); return rc ? rc : count; } -static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store); +/* + * "open code" the old BUS_ATTR() macro here. We want to use BUS_ATTR_WO() + * here, but can not use it as earlier in the file we have + * DEVICE_ATTR_WO(uevent), which would cause a clash with the with the store + * function name. + */ +static struct bus_attribute bus_attr_uevent = __ATTR(uevent, S_IWUSR, NULL, + bus_uevent_store); /** * bus_register - register a driver-core subsystem diff --git a/drivers/base/class.c b/drivers/base/class.c index 54def4e02f00..d8a6a5864c2e 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -117,16 +117,22 @@ static void class_put(struct class *cls) kset_put(&cls->p->subsys); } +static struct device *klist_class_to_dev(struct klist_node *n) +{ + struct device_private *p = to_device_private_class(n); + return p->device; +} + static void klist_class_dev_get(struct klist_node *n) { - struct device *dev = container_of(n, struct device, knode_class); + struct device *dev = klist_class_to_dev(n); get_device(dev); } static void klist_class_dev_put(struct klist_node *n) { - struct device *dev = container_of(n, struct device, knode_class); + struct device *dev = klist_class_to_dev(n); put_device(dev); } @@ -277,7 +283,7 @@ void class_dev_iter_init(struct class_dev_iter *iter, struct class *class, struct klist_node *start_knode = NULL; if (start) - start_knode = &start->knode_class; + start_knode = &start->p->knode_class; klist_iter_init_node(&class->p->klist_devices, &iter->ki, start_knode); iter->type = type; } @@ -304,7 +310,7 @@ struct device *class_dev_iter_next(struct class_dev_iter *iter) knode = klist_next(&iter->ki); if (!knode) return NULL; - dev = container_of(knode, struct device, knode_class); + dev = klist_class_to_dev(knode); if (!iter->type || iter->type == dev->type) return dev; } diff --git a/drivers/base/component.c b/drivers/base/component.c index 7dbc41cccd58..532a3a5d8f63 100644 --- a/drivers/base/component.c +++ b/drivers/base/component.c @@ -27,7 +27,7 @@ * helper fills the niche of aggregate drivers for specific hardware, where * further standardization into a subsystem would not be practical. The common * example is when a logical device (e.g. a DRM display driver) is spread around - * the SoC on various component (scanout engines, blending blocks, transcoders + * the SoC on various components (scanout engines, blending blocks, transcoders * for various outputs and so on). * * The component helper also doesn't solve runtime dependencies, e.g. for system @@ -378,7 +378,7 @@ static void __component_match_add(struct device *master, } /** - * component_match_add_release - add a component match with release callback + * component_match_add_release - add a component match entry with release callback * @master: device with the aggregate driver * @matchptr: pointer to the list of component matches * @release: release function for @compare_data @@ -408,7 +408,7 @@ void component_match_add_release(struct device *master, EXPORT_SYMBOL(component_match_add_release); /** - * component_match_add_typed - add a compent match for a typed component + * component_match_add_typed - add a component match entry for a typed component * @master: device with the aggregate driver * @matchptr: pointer to the list of component matches * @compare_typed: compare function to match against all typed components @@ -537,11 +537,11 @@ static void component_unbind(struct component *component, } /** - * component_unbind_all - unbind all component to an aggregate driver + * component_unbind_all - unbind all components of an aggregate driver * @master_dev: device with the aggregate driver * @data: opaque pointer, passed to all components * - * Unbinds all components to the aggregate @dev by passing @data to their + * Unbinds all components of the aggregate @dev by passing @data to their * &component_ops.unbind functions. Should be called from * &component_master_ops.unbind. */ @@ -619,11 +619,11 @@ static int component_bind(struct component *component, struct master *master, } /** - * component_bind_all - bind all component to an aggregate driver + * component_bind_all - bind all components of an aggregate driver * @master_dev: device with the aggregate driver * @data: opaque pointer, passed to all components * - * Binds all components to the aggregate @dev by passing @data to their + * Binds all components of the aggregate @dev by passing @data to their * &component_ops.bind functions. Should be called from * &component_master_ops.bind. */ diff --git a/drivers/base/core.c b/drivers/base/core.c index 0073b09bb99f..4aeaa0c92bda 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -179,10 +179,31 @@ void device_pm_move_to_tail(struct device *dev) * of the link. If DL_FLAG_PM_RUNTIME is not set, DL_FLAG_RPM_ACTIVE will be * ignored. * - * If the DL_FLAG_AUTOREMOVE_CONSUMER is set, the link will be removed - * automatically when the consumer device driver unbinds from it. - * The combination of both DL_FLAG_AUTOREMOVE_CONSUMER and DL_FLAG_STATELESS - * set is invalid and will cause NULL to be returned. + * If DL_FLAG_STATELESS is set in @flags, the link is not going to be managed by + * the driver core and, in particular, the caller of this function is expected + * to drop the reference to the link acquired by it directly. + * + * If that flag is not set, however, the caller of this function is handing the + * management of the link over to the driver core entirely and its return value + * can only be used to check whether or not the link is present. In that case, + * the DL_FLAG_AUTOREMOVE_CONSUMER and DL_FLAG_AUTOREMOVE_SUPPLIER device link + * flags can be used to indicate to the driver core when the link can be safely + * deleted. Namely, setting one of them in @flags indicates to the driver core + * that the link is not going to be used (by the given caller of this function) + * after unbinding the consumer or supplier driver, respectively, from its + * device, so the link can be deleted at that point. If none of them is set, + * the link will be maintained until one of the devices pointed to by it (either + * the consumer or the supplier) is unregistered. + * + * Also, if DL_FLAG_STATELESS, DL_FLAG_AUTOREMOVE_CONSUMER and + * DL_FLAG_AUTOREMOVE_SUPPLIER are not set in @flags (that is, a persistent + * managed device link is being added), the DL_FLAG_AUTOPROBE_CONSUMER flag can + * be used to request the driver core to automaticall probe for a consmer + * driver after successfully binding a driver to the supplier device. + * + * The combination of DL_FLAG_STATELESS and either DL_FLAG_AUTOREMOVE_CONSUMER + * or DL_FLAG_AUTOREMOVE_SUPPLIER set in @flags at the same time is invalid and + * will cause NULL to be returned upfront. * * A side effect of the link creation is re-ordering of dpm_list and the * devices_kset list by moving the consumer device and all devices depending @@ -199,10 +220,22 @@ struct device_link *device_link_add(struct device *consumer, struct device_link *link; if (!consumer || !supplier || - ((flags & DL_FLAG_STATELESS) && - (flags & DL_FLAG_AUTOREMOVE_CONSUMER))) + (flags & DL_FLAG_STATELESS && + flags & (DL_FLAG_AUTOREMOVE_CONSUMER | + DL_FLAG_AUTOREMOVE_SUPPLIER | + DL_FLAG_AUTOPROBE_CONSUMER)) || + (flags & DL_FLAG_AUTOPROBE_CONSUMER && + flags & (DL_FLAG_AUTOREMOVE_CONSUMER | + DL_FLAG_AUTOREMOVE_SUPPLIER))) return NULL; + if (flags & DL_FLAG_PM_RUNTIME && flags & DL_FLAG_RPM_ACTIVE) { + if (pm_runtime_get_sync(supplier) < 0) { + pm_runtime_put_noidle(supplier); + return NULL; + } + } + device_links_write_lock(); device_pm_lock(); @@ -217,35 +250,71 @@ struct device_link *device_link_add(struct device *consumer, goto out; } - list_for_each_entry(link, &supplier->links.consumers, s_node) - if (link->consumer == consumer) { + /* + * DL_FLAG_AUTOREMOVE_SUPPLIER indicates that the link will be needed + * longer than for DL_FLAG_AUTOREMOVE_CONSUMER and setting them both + * together doesn't make sense, so prefer DL_FLAG_AUTOREMOVE_SUPPLIER. + */ + if (flags & DL_FLAG_AUTOREMOVE_SUPPLIER) + flags &= ~DL_FLAG_AUTOREMOVE_CONSUMER; + + list_for_each_entry(link, &supplier->links.consumers, s_node) { + if (link->consumer != consumer) + continue; + + /* + * Don't return a stateless link if the caller wants a stateful + * one and vice versa. + */ + if (WARN_ON((flags & DL_FLAG_STATELESS) != (link->flags & DL_FLAG_STATELESS))) { + link = NULL; + goto out; + } + + if (flags & DL_FLAG_PM_RUNTIME) { + if (!(link->flags & DL_FLAG_PM_RUNTIME)) { + pm_runtime_new_link(consumer); + link->flags |= DL_FLAG_PM_RUNTIME; + } + if (flags & DL_FLAG_RPM_ACTIVE) + refcount_inc(&link->rpm_active); + } + + if (flags & DL_FLAG_STATELESS) { kref_get(&link->kref); goto out; } + /* + * If the life time of the link following from the new flags is + * longer than indicated by the flags of the existing link, + * update the existing link to stay around longer. + */ + if (flags & DL_FLAG_AUTOREMOVE_SUPPLIER) { + if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER) { + link->flags &= ~DL_FLAG_AUTOREMOVE_CONSUMER; + link->flags |= DL_FLAG_AUTOREMOVE_SUPPLIER; + } + } else if (!(flags & DL_FLAG_AUTOREMOVE_CONSUMER)) { + link->flags &= ~(DL_FLAG_AUTOREMOVE_CONSUMER | + DL_FLAG_AUTOREMOVE_SUPPLIER); + } + goto out; + } + link = kzalloc(sizeof(*link), GFP_KERNEL); if (!link) goto out; + refcount_set(&link->rpm_active, 1); + if (flags & DL_FLAG_PM_RUNTIME) { - if (flags & DL_FLAG_RPM_ACTIVE) { - if (pm_runtime_get_sync(supplier) < 0) { - pm_runtime_put_noidle(supplier); - kfree(link); - link = NULL; - goto out; - } - link->rpm_active = true; - } + if (flags & DL_FLAG_RPM_ACTIVE) + refcount_inc(&link->rpm_active); + pm_runtime_new_link(consumer); - /* - * If the link is being added by the consumer driver at probe - * time, balance the decrementation of the supplier's runtime PM - * usage counter after consumer probe in driver_probe_device(). - */ - if (consumer->links.status == DL_DEV_PROBING) - pm_runtime_get_noresume(supplier); } + get_device(supplier); link->supplier = supplier; INIT_LIST_HEAD(&link->s_node); @@ -260,17 +329,26 @@ struct device_link *device_link_add(struct device *consumer, link->status = DL_STATE_NONE; } else { switch (supplier->links.status) { - case DL_DEV_DRIVER_BOUND: + case DL_DEV_PROBING: switch (consumer->links.status) { case DL_DEV_PROBING: /* - * Some callers expect the link creation during - * consumer driver probe to resume the supplier - * even without DL_FLAG_RPM_ACTIVE. + * A consumer driver can create a link to a + * supplier that has not completed its probing + * yet as long as it knows that the supplier is + * already functional (for example, it has just + * acquired some resources from the supplier). */ - if (flags & DL_FLAG_PM_RUNTIME) - pm_runtime_resume(supplier); - + link->status = DL_STATE_CONSUMER_PROBE; + break; + default: + link->status = DL_STATE_DORMANT; + break; + } + break; + case DL_DEV_DRIVER_BOUND: + switch (consumer->links.status) { + case DL_DEV_PROBING: link->status = DL_STATE_CONSUMER_PROBE; break; case DL_DEV_DRIVER_BOUND: @@ -291,6 +369,14 @@ struct device_link *device_link_add(struct device *consumer, } /* + * Some callers expect the link creation during consumer driver probe to + * resume the supplier even without DL_FLAG_RPM_ACTIVE. + */ + if (link->status == DL_STATE_CONSUMER_PROBE && + flags & DL_FLAG_PM_RUNTIME) + pm_runtime_resume(supplier); + + /* * Move the consumer and all of the devices depending on it to the end * of dpm_list and the devices_kset list. * @@ -302,17 +388,24 @@ struct device_link *device_link_add(struct device *consumer, list_add_tail_rcu(&link->s_node, &supplier->links.consumers); list_add_tail_rcu(&link->c_node, &consumer->links.suppliers); - dev_info(consumer, "Linked as a consumer to %s\n", dev_name(supplier)); + dev_dbg(consumer, "Linked as a consumer to %s\n", dev_name(supplier)); out: device_pm_unlock(); device_links_write_unlock(); + + if ((flags & DL_FLAG_PM_RUNTIME && flags & DL_FLAG_RPM_ACTIVE) && !link) + pm_runtime_put(supplier); + return link; } EXPORT_SYMBOL_GPL(device_link_add); static void device_link_free(struct device_link *link) { + while (refcount_dec_not_one(&link->rpm_active)) + pm_runtime_put(link->supplier); + put_device(link->consumer); put_device(link->supplier); kfree(link); @@ -328,8 +421,8 @@ static void __device_link_del(struct kref *kref) { struct device_link *link = container_of(kref, struct device_link, kref); - dev_info(link->consumer, "Dropping the link to %s\n", - dev_name(link->supplier)); + dev_dbg(link->consumer, "Dropping the link to %s\n", + dev_name(link->supplier)); if (link->flags & DL_FLAG_PM_RUNTIME) pm_runtime_drop_link(link->consumer); @@ -355,8 +448,16 @@ static void __device_link_del(struct kref *kref) } #endif /* !CONFIG_SRCU */ +static void device_link_put_kref(struct device_link *link) +{ + if (link->flags & DL_FLAG_STATELESS) + kref_put(&link->kref, __device_link_del); + else + WARN(1, "Unable to drop a managed device link reference\n"); +} + /** - * device_link_del - Delete a link between two devices. + * device_link_del - Delete a stateless link between two devices. * @link: Device link to delete. * * The caller must ensure proper synchronization of this function with runtime @@ -368,14 +469,14 @@ void device_link_del(struct device_link *link) { device_links_write_lock(); device_pm_lock(); - kref_put(&link->kref, __device_link_del); + device_link_put_kref(link); device_pm_unlock(); device_links_write_unlock(); } EXPORT_SYMBOL_GPL(device_link_del); /** - * device_link_remove - remove a link between two devices. + * device_link_remove - Delete a stateless link between two devices. * @consumer: Consumer end of the link. * @supplier: Supplier end of the link. * @@ -394,7 +495,7 @@ void device_link_remove(void *consumer, struct device *supplier) list_for_each_entry(link, &supplier->links.consumers, s_node) { if (link->consumer == consumer) { - kref_put(&link->kref, __device_link_del); + device_link_put_kref(link); break; } } @@ -474,8 +575,21 @@ void device_links_driver_bound(struct device *dev) if (link->flags & DL_FLAG_STATELESS) continue; + /* + * Links created during consumer probe may be in the "consumer + * probe" state to start with if the supplier is still probing + * when they are created and they may become "active" if the + * consumer probe returns first. Skip them here. + */ + if (link->status == DL_STATE_CONSUMER_PROBE || + link->status == DL_STATE_ACTIVE) + continue; + WARN_ON(link->status != DL_STATE_DORMANT); WRITE_ONCE(link->status, DL_STATE_AVAILABLE); + + if (link->flags & DL_FLAG_AUTOPROBE_CONSUMER) + driver_deferred_probe_add(link->consumer); } list_for_each_entry(link, &dev->links.suppliers, c_node) { @@ -512,18 +626,49 @@ static void __device_links_no_driver(struct device *dev) continue; if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER) - kref_put(&link->kref, __device_link_del); - else if (link->status != DL_STATE_SUPPLIER_UNBIND) + __device_link_del(&link->kref); + else if (link->status == DL_STATE_CONSUMER_PROBE || + link->status == DL_STATE_ACTIVE) WRITE_ONCE(link->status, DL_STATE_AVAILABLE); } dev->links.status = DL_DEV_NO_DRIVER; } +/** + * device_links_no_driver - Update links after failing driver probe. + * @dev: Device whose driver has just failed to probe. + * + * Clean up leftover links to consumers for @dev and invoke + * %__device_links_no_driver() to update links to suppliers for it as + * appropriate. + * + * Links with the DL_FLAG_STATELESS flag set are ignored. + */ void device_links_no_driver(struct device *dev) { + struct device_link *link; + device_links_write_lock(); + + list_for_each_entry(link, &dev->links.consumers, s_node) { + if (link->flags & DL_FLAG_STATELESS) + continue; + + /* + * The probe has failed, so if the status of the link is + * "consumer probe" or "active", it must have been added by + * a probing consumer while this device was still probing. + * Change its state to "dormant", as it represents a valid + * relationship, but it is not functionally meaningful. + */ + if (link->status == DL_STATE_CONSUMER_PROBE || + link->status == DL_STATE_ACTIVE) + WRITE_ONCE(link->status, DL_STATE_DORMANT); + } + __device_links_no_driver(dev); + device_links_write_unlock(); } @@ -539,11 +684,11 @@ void device_links_no_driver(struct device *dev) */ void device_links_driver_cleanup(struct device *dev) { - struct device_link *link; + struct device_link *link, *ln; device_links_write_lock(); - list_for_each_entry(link, &dev->links.consumers, s_node) { + list_for_each_entry_safe(link, ln, &dev->links.consumers, s_node) { if (link->flags & DL_FLAG_STATELESS) continue; @@ -557,7 +702,7 @@ void device_links_driver_cleanup(struct device *dev) */ if (link->status == DL_STATE_SUPPLIER_UNBIND && link->flags & DL_FLAG_AUTOREMOVE_SUPPLIER) - kref_put(&link->kref, __device_link_del); + __device_link_del(&link->kref); WRITE_ONCE(link->status, DL_STATE_DORMANT); } @@ -1966,7 +2111,7 @@ int device_add(struct device *dev) if (dev->class) { mutex_lock(&dev->class->p->mutex); /* tie the class to the device */ - klist_add_tail(&dev->knode_class, + klist_add_tail(&dev->p->knode_class, &dev->class->p->klist_devices); /* notify any interfaces that the device is here */ @@ -2080,6 +2225,17 @@ void device_del(struct device *dev) struct kobject *glue_dir = NULL; struct class_interface *class_intf; + /* + * Hold the device lock and set the "dead" flag to guarantee that + * the update behavior is consistent with the other bitfields near + * it and that we cannot have an asynchronous probe routine trying + * to run while we are tearing out the bus/class/sysfs from + * underneath the device. + */ + device_lock(dev); + dev->p->dead = true; + device_unlock(dev); + /* Notify clients of device removal. This call must come * before dpm_sysfs_remove(). */ @@ -2105,7 +2261,7 @@ void device_del(struct device *dev) if (class_intf->remove_dev) class_intf->remove_dev(dev, class_intf); /* remove the device from the class list */ - klist_del(&dev->knode_class); + klist_del(&dev->p->knode_class); mutex_unlock(&dev->class->p->mutex); } device_remove_file(dev, &dev_attr_uevent); diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 6ce93a52bf3f..668139cfa664 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -409,6 +409,7 @@ static void device_create_release(struct device *dev) kfree(dev); } +__printf(4, 0) static struct device * __cpu_device_create(struct device *parent, void *drvdata, const struct attribute_group **groups, diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 8ac10af17c00..a823f469e53f 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -57,6 +57,10 @@ static atomic_t deferred_trigger_count = ATOMIC_INIT(0); static struct dentry *deferred_devices; static bool initcalls_done; +/* Save the async probe drivers' name from kernel cmdline */ +#define ASYNC_DRV_NAMES_MAX_LEN 256 +static char async_probe_drv_names[ASYNC_DRV_NAMES_MAX_LEN]; + /* * In some cases, like suspend to RAM or hibernation, It might be reasonable * to prohibit probing of devices as it could be unsafe. @@ -116,7 +120,7 @@ static void deferred_probe_work_func(struct work_struct *work) } static DECLARE_WORK(deferred_probe_work, deferred_probe_work_func); -static void driver_deferred_probe_add(struct device *dev) +void driver_deferred_probe_add(struct device *dev) { mutex_lock(&deferred_probe_mutex); if (list_empty(&dev->p->deferred_probe)) { @@ -674,6 +678,23 @@ int driver_probe_device(struct device_driver *drv, struct device *dev) return ret; } +static inline bool cmdline_requested_async_probing(const char *drv_name) +{ + return parse_option_str(async_probe_drv_names, drv_name); +} + +/* The option format is "driver_async_probe=drv_name1,drv_name2,..." */ +static int __init save_async_options(char *buf) +{ + if (strlen(buf) >= ASYNC_DRV_NAMES_MAX_LEN) + printk(KERN_WARNING + "Too long list of driver names for 'driver_async_probe'!\n"); + + strlcpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN); + return 0; +} +__setup("driver_async_probe=", save_async_options); + bool driver_allows_async_probing(struct device_driver *drv) { switch (drv->probe_type) { @@ -684,6 +705,9 @@ bool driver_allows_async_probing(struct device_driver *drv) return false; default: + if (cmdline_requested_async_probing(drv->name)) + return true; + if (module_requested_async_probing(drv->owner)) return true; @@ -731,15 +755,6 @@ static int __device_attach_driver(struct device_driver *drv, void *_data) bool async_allowed; int ret; - /* - * Check if device has already been claimed. This may - * happen with driver loading, device discovery/registration, - * and deferred probe processing happens all at once with - * multiple threads. - */ - if (dev->driver) - return -EBUSY; - ret = driver_match_device(drv, dev); if (ret == 0) { /* no match */ @@ -774,6 +789,15 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie) device_lock(dev); + /* + * Check if device has already been removed or claimed. This may + * happen with driver loading, device discovery/registration, + * and deferred probe processing happens all at once with + * multiple threads. + */ + if (dev->p->dead || dev->driver) + goto out_unlock; + if (dev->parent) pm_runtime_get_sync(dev->parent); @@ -784,7 +808,7 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie) if (dev->parent) pm_runtime_put(dev->parent); - +out_unlock: device_unlock(dev); put_device(dev); @@ -829,7 +853,7 @@ static int __device_attach(struct device *dev, bool allow_async) */ dev_dbg(dev, "scheduling asynchronous probe\n"); get_device(dev); - async_schedule(__device_attach_async_helper, dev); + async_schedule_dev(__device_attach_async_helper, dev); } else { pm_request_idle(dev); } @@ -867,6 +891,88 @@ void device_initial_probe(struct device *dev) __device_attach(dev, true); } +/* + * __device_driver_lock - acquire locks needed to manipulate dev->drv + * @dev: Device we will update driver info for + * @parent: Parent device. Needed if the bus requires parent lock + * + * This function will take the required locks for manipulating dev->drv. + * Normally this will just be the @dev lock, but when called for a USB + * interface, @parent lock will be held as well. + */ +static void __device_driver_lock(struct device *dev, struct device *parent) +{ + if (parent && dev->bus->need_parent_lock) + device_lock(parent); + device_lock(dev); +} + +/* + * __device_driver_unlock - release locks needed to manipulate dev->drv + * @dev: Device we will update driver info for + * @parent: Parent device. Needed if the bus requires parent lock + * + * This function will release the required locks for manipulating dev->drv. + * Normally this will just be the the @dev lock, but when called for a + * USB interface, @parent lock will be released as well. + */ +static void __device_driver_unlock(struct device *dev, struct device *parent) +{ + device_unlock(dev); + if (parent && dev->bus->need_parent_lock) + device_unlock(parent); +} + +/** + * device_driver_attach - attach a specific driver to a specific device + * @drv: Driver to attach + * @dev: Device to attach it to + * + * Manually attach driver to a device. Will acquire both @dev lock and + * @dev->parent lock if needed. + */ +int device_driver_attach(struct device_driver *drv, struct device *dev) +{ + i |