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Driver core patches for 4.10-rc1

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Here's the new driver core patches for 4.10-rc1.
 
 Big thing here is the nice addition of "functional dependencies" to the
 driver core.  The idea has been talked about for a very long time, great
 job to Rafael for stepping up and implementing it. It's been tested for
 longer than the 4.9-rc1 date, we held off on merging it earlier in order
 to feel more comfortable about it.
 
 Other than that, it's just a handful of small other patches, some good
 cleanups to the mess that is the firmware class code, and we have a test
 driver for the deferred probe logic.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Merge tag 'driver-core-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here's the new driver core patches for 4.10-rc1.

  Big thing here is the nice addition of "functional dependencies" to
  the driver core. The idea has been talked about for a very long time,
  great job to Rafael for stepping up and implementing it. It's been
  tested for longer than the 4.9-rc1 date, we held off on merging it
  earlier in order to feel more comfortable about it.

  Other than that, it's just a handful of small other patches, some good
  cleanups to the mess that is the firmware class code, and we have a
  test driver for the deferred probe logic.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (30 commits)
  firmware: Correct handling of fw_state_wait() return value
  driver core: Silence device links sphinx warning
  firmware: remove warning at documentation generation time
  drivers: base: dma-mapping: Fix typo in dmam_alloc_non_coherent comments
  driver core: test_async: fix up typo found by 0-day
  firmware: move fw_state_is_done() into UHM section
  firmware: do not use fw_lock for fw_state protection
  firmware: drop bit ops in favor of simple state machine
  firmware: refactor loading status
  firmware: fix usermode helper fallback loading
  driver core: firmware_class: convert to use class_groups
  driver core: devcoredump: convert to use class_groups
  driver core: class: add class_groups support
  kernfs: Declare two local data structures static
  driver-core: fix platform_no_drv_owner.cocci warnings
  drivers/base/memory.c: Remove unused 'first_page' variable
  driver core: add CLASS_ATTR_WO()
  drivers: base: cacheinfo: support DT overrides for cache properties
  drivers: base: cacheinfo: add pr_fmt logging
  drivers: base: cacheinfo: fix boot error message when acpi is enabled
  ...
This commit is contained in:
Linus Torvalds 2016-12-13 11:42:18 -08:00
commit 098c30557a
26 changed files with 1517 additions and 128 deletions
Download patch file Download diff file Expand all files Collapse all files

2
drivers/base/Kconfig
View file

@ -224,6 +224,8 @@ config DEBUG_TEST_DRIVER_REMOVE
unusable. You should say N here unless you are explicitly looking to
test this functionality.
source "drivers/base/test/Kconfig"
config SYS_HYPERVISOR
bool
default n

2
drivers/base/Makefile
View file

@ -24,5 +24,7 @@ obj-$(CONFIG_PINCTRL) += pinctrl.o
obj-$(CONFIG_DEV_COREDUMP) += devcoredump.o
obj-$(CONFIG_GENERIC_MSI_IRQ_DOMAIN) += platform-msi.o
obj-y += test/
ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG

15
drivers/base/base.h
View file

@ -107,6 +107,9 @@ extern void bus_remove_device(struct device *dev);
extern int bus_add_driver(struct device_driver *drv);
extern void bus_remove_driver(struct device_driver *drv);
extern void device_release_driver_internal(struct device *dev,
struct device_driver *drv,
struct device *parent);
extern void driver_detach(struct device_driver *drv);
extern int driver_probe_device(struct device_driver *drv, struct device *dev);
@ -138,6 +141,8 @@ extern void device_unblock_probing(void);
extern struct kset *devices_kset;
extern void devices_kset_move_last(struct device *dev);
extern struct device_attribute dev_attr_deferred_probe;
#if defined(CONFIG_MODULES) && defined(CONFIG_SYSFS)
extern void module_add_driver(struct module *mod, struct device_driver *drv);
extern void module_remove_driver(struct device_driver *drv);
@ -152,3 +157,13 @@ extern int devtmpfs_init(void);
#else
static inline int devtmpfs_init(void) { return 0; }
#endif
/* Device links support */
extern int device_links_read_lock(void);
extern void device_links_read_unlock(int idx);
extern int device_links_check_suppliers(struct device *dev);
extern void device_links_driver_bound(struct device *dev);
extern void device_links_driver_cleanup(struct device *dev);
extern void device_links_no_driver(struct device *dev);
extern bool device_links_busy(struct device *dev);
extern void device_links_unbind_consumers(struct device *dev);

138
drivers/base/cacheinfo.c
View file

@ -16,6 +16,9 @@
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/acpi.h>
#include <linux/bitops.h>
#include <linux/cacheinfo.h>
#include <linux/compiler.h>
@ -85,7 +88,120 @@ static inline bool cache_leaves_are_shared(struct cacheinfo *this_leaf,
{
return sib_leaf->of_node == this_leaf->of_node;
}
/* OF properties to query for a given cache type */
struct cache_type_info {
const char *size_prop;
const char *line_size_props[2];
const char *nr_sets_prop;
};
static const struct cache_type_info cache_type_info[] = {
{
.size_prop = "cache-size",
.line_size_props = { "cache-line-size",
"cache-block-size", },
.nr_sets_prop = "cache-sets",
}, {
.size_prop = "i-cache-size",
.line_size_props = { "i-cache-line-size",
"i-cache-block-size", },
.nr_sets_prop = "i-cache-sets",
}, {
.size_prop = "d-cache-size",
.line_size_props = { "d-cache-line-size",
"d-cache-block-size", },
.nr_sets_prop = "d-cache-sets",
},
};
static inline int get_cacheinfo_idx(enum cache_type type)
{
if (type == CACHE_TYPE_UNIFIED)
return 0;
return type;
}
static void cache_size(struct cacheinfo *this_leaf)
{
const char *propname;
const __be32 *cache_size;
int ct_idx;
ct_idx = get_cacheinfo_idx(this_leaf->type);
propname = cache_type_info[ct_idx].size_prop;
cache_size = of_get_property(this_leaf->of_node, propname, NULL);
if (cache_size)
this_leaf->size = of_read_number(cache_size, 1);
}
/* not cache_line_size() because that's a macro in include/linux/cache.h */
static void cache_get_line_size(struct cacheinfo *this_leaf)
{
const __be32 *line_size;
int i, lim, ct_idx;
ct_idx = get_cacheinfo_idx(this_leaf->type);
lim = ARRAY_SIZE(cache_type_info[ct_idx].line_size_props);
for (i = 0; i < lim; i++) {
const char *propname;
propname = cache_type_info[ct_idx].line_size_props[i];
line_size = of_get_property(this_leaf->of_node, propname, NULL);
if (line_size)
break;
}
if (line_size)
this_leaf->coherency_line_size = of_read_number(line_size, 1);
}
static void cache_nr_sets(struct cacheinfo *this_leaf)
{
const char *propname;
const __be32 *nr_sets;
int ct_idx;
ct_idx = get_cacheinfo_idx(this_leaf->type);
propname = cache_type_info[ct_idx].nr_sets_prop;
nr_sets = of_get_property(this_leaf->of_node, propname, NULL);
if (nr_sets)
this_leaf->number_of_sets = of_read_number(nr_sets, 1);
}
static void cache_associativity(struct cacheinfo *this_leaf)
{
unsigned int line_size = this_leaf->coherency_line_size;
unsigned int nr_sets = this_leaf->number_of_sets;
unsigned int size = this_leaf->size;
/*
* If the cache is fully associative, there is no need to
* check the other properties.
*/
if (!(nr_sets == 1) && (nr_sets > 0 && size > 0 && line_size > 0))
this_leaf->ways_of_associativity = (size / nr_sets) / line_size;
}
static void cache_of_override_properties(unsigned int cpu)
{
int index;
struct cacheinfo *this_leaf;
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
for (index = 0; index < cache_leaves(cpu); index++) {
this_leaf = this_cpu_ci->info_list + index;
cache_size(this_leaf);
cache_get_line_size(this_leaf);
cache_nr_sets(this_leaf);
cache_associativity(this_leaf);
}
}
#else
static void cache_of_override_properties(unsigned int cpu) { }
static inline int cache_setup_of_node(unsigned int cpu) { return 0; }
static inline bool cache_leaves_are_shared(struct cacheinfo *this_leaf,
struct cacheinfo *sib_leaf)
@ -104,9 +220,16 @@ static int cache_shared_cpu_map_setup(unsigned int cpu)
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
struct cacheinfo *this_leaf, *sib_leaf;
unsigned int index;
int ret;
int ret = 0;
ret = cache_setup_of_node(cpu);
if (this_cpu_ci->cpu_map_populated)
return 0;
if (of_have_populated_dt())
ret = cache_setup_of_node(cpu);
else if (!acpi_disabled)
/* No cache property/hierarchy support yet in ACPI */
ret = -ENOTSUPP;
if (ret)
return ret;
@ -161,6 +284,12 @@ static void cache_shared_cpu_map_remove(unsigned int cpu)
}
}
static void cache_override_properties(unsigned int cpu)
{
if (of_have_populated_dt())
return cache_of_override_properties(cpu);
}
static void free_cache_attributes(unsigned int cpu)
{
if (!per_cpu_cacheinfo(cpu))
@ -203,10 +332,11 @@ static int detect_cache_attributes(unsigned int cpu)
*/
ret = cache_shared_cpu_map_setup(cpu);
if (ret) {
pr_warn("Unable to detect cache hierarchy from DT for CPU %d\n",
cpu);
pr_warn("Unable to detect cache hierarchy for CPU %d\n", cpu);
goto free_ci;
}
cache_override_properties(cpu);
return 0;
free_ci:

15
drivers/base/class.c
View file

@ -163,6 +163,18 @@ static void klist_class_dev_put(struct klist_node *n)
put_device(dev);
}
static int class_add_groups(struct class *cls,
const struct attribute_group **groups)
{
return sysfs_create_groups(&cls->p->subsys.kobj, groups);
}
static void class_remove_groups(struct class *cls,
const struct attribute_group **groups)
{
return sysfs_remove_groups(&cls->p->subsys.kobj, groups);
}
int __class_register(struct class *cls, struct lock_class_key *key)
{
struct subsys_private *cp;
@ -203,6 +215,8 @@ int __class_register(struct class *cls, struct lock_class_key *key)
kfree(cp);
return error;
}
error = class_add_groups(class_get(cls), cls->class_groups);
class_put(cls);
error = add_class_attrs(class_get(cls));
class_put(cls);
return error;
@ -213,6 +227,7 @@ void class_unregister(struct class *cls)
{
pr_debug("device class '%s': unregistering\n", cls->name);
remove_class_attrs(cls);
class_remove_groups(cls, cls->class_groups);
kset_unregister(&cls->p->subsys);
}

578
drivers/base/core.c
View file

@ -44,6 +44,572 @@ static int __init sysfs_deprecated_setup(char *arg)
early_param("sysfs.deprecated", sysfs_deprecated_setup);
#endif
/* Device links support. */
#ifdef CONFIG_SRCU
static DEFINE_MUTEX(device_links_lock);
DEFINE_STATIC_SRCU(device_links_srcu);
static inline void device_links_write_lock(void)
{
mutex_lock(&device_links_lock);
}
static inline void device_links_write_unlock(void)
{
mutex_unlock(&device_links_lock);
}
int device_links_read_lock(void)
{
return srcu_read_lock(&device_links_srcu);
}
void device_links_read_unlock(int idx)
{
srcu_read_unlock(&device_links_srcu, idx);
}
#else /* !CONFIG_SRCU */
static DECLARE_RWSEM(device_links_lock);
static inline void device_links_write_lock(void)
{
down_write(&device_links_lock);
}
static inline void device_links_write_unlock(void)
{
up_write(&device_links_lock);
}
int device_links_read_lock(void)
{
down_read(&device_links_lock);
return 0;
}
void device_links_read_unlock(int not_used)
{
up_read(&device_links_lock);
}
#endif /* !CONFIG_SRCU */
/**
* device_is_dependent - Check if one device depends on another one
* @dev: Device to check dependencies for.
* @target: Device to check against.
*
* Check if @target depends on @dev or any device dependent on it (its child or
* its consumer etc). Return 1 if that is the case or 0 otherwise.
*/
static int device_is_dependent(struct device *dev, void *target)
{
struct device_link *link;
int ret;
if (WARN_ON(dev == target))
return 1;
ret = device_for_each_child(dev, target, device_is_dependent);
if (ret)
return ret;
list_for_each_entry(link, &dev->links.consumers, s_node) {
if (WARN_ON(link->consumer == target))
return 1;
ret = device_is_dependent(link->consumer, target);
if (ret)
break;
}
return ret;
}
static int device_reorder_to_tail(struct device *dev, void *not_used)
{
struct device_link *link;
/*
* Devices that have not been registered yet will be put to the ends
* of the lists during the registration, so skip them here.
*/
if (device_is_registered(dev))
devices_kset_move_last(dev);
if (device_pm_initialized(dev))
device_pm_move_last(dev);
device_for_each_child(dev, NULL, device_reorder_to_tail);
list_for_each_entry(link, &dev->links.consumers, s_node)
device_reorder_to_tail(link->consumer, NULL);
return 0;
}
/**
* device_link_add - Create a link between two devices.
* @consumer: Consumer end of the link.
* @supplier: Supplier end of the link.
* @flags: Link flags.
*
* The caller is responsible for the proper synchronization of the link creation
* with runtime PM. First, setting the DL_FLAG_PM_RUNTIME flag will cause the
* runtime PM framework to take the link into account. Second, if the
* DL_FLAG_RPM_ACTIVE flag is set in addition to it, the supplier devices will
* be forced into the active metastate and reference-counted upon the creation
* of the link. If DL_FLAG_PM_RUNTIME is not set, DL_FLAG_RPM_ACTIVE will be
* ignored.
*
* If the DL_FLAG_AUTOREMOVE is set, the link will be removed automatically
* when the consumer device driver unbinds from it. The combination of both
* DL_FLAG_AUTOREMOVE and DL_FLAG_STATELESS set is invalid and will cause NULL
* to be returned.
*
* 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
* on it to the ends of these lists (that does not happen to devices that have
* not been registered when this function is called).
*
* The supplier device is required to be registered when this function is called
* and NULL will be returned if that is not the case. The consumer device need
* not be registered, however.
*/
struct device_link *device_link_add(struct device *consumer,
struct device *supplier, u32 flags)
{
struct device_link *link;
if (!consumer || !supplier ||
((flags & DL_FLAG_STATELESS) && (flags & DL_FLAG_AUTOREMOVE)))
return NULL;
device_links_write_lock();
device_pm_lock();
/*
* If the supplier has not been fully registered yet or there is a
* reverse dependency between the consumer and the supplier already in
* the graph, return NULL.
*/
if (!device_pm_initialized(supplier)
|| device_is_dependent(consumer, supplier)) {
link = NULL;
goto out;
}
list_for_each_entry(link, &supplier->links.consumers, s_node)
if (link->consumer == consumer)
goto out;
link = kzalloc(sizeof(*link), GFP_KERNEL);
if (!link)
goto out;
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;
}
pm_runtime_new_link(consumer);
}
get_device(supplier);
link->supplier = supplier;
INIT_LIST_HEAD(&link->s_node);
get_device(consumer);
link->consumer = consumer;
INIT_LIST_HEAD(&link->c_node);
link->flags = flags;
/* Determine the initial link state. */
if (flags & DL_FLAG_STATELESS) {
link->status = DL_STATE_NONE;
} else {
switch (supplier->links.status) {
case DL_DEV_DRIVER_BOUND:
switch (consumer->links.status) {
case DL_DEV_PROBING:
/*
* Balance the decrementation of the supplier's
* runtime PM usage counter after consumer probe
* in driver_probe_device().
*/
if (flags & DL_FLAG_PM_RUNTIME)
pm_runtime_get_sync(supplier);
link->status = DL_STATE_CONSUMER_PROBE;
break;
case DL_DEV_DRIVER_BOUND:
link->status = DL_STATE_ACTIVE;
break;
default:
link->status = DL_STATE_AVAILABLE;
break;
}
break;
case DL_DEV_UNBINDING:
link->status = DL_STATE_SUPPLIER_UNBIND;
break;
default:
link->status = DL_STATE_DORMANT;
break;
}
}
/*
* Move the consumer and all of the devices depending on it to the end
* of dpm_list and the devices_kset list.
*
* It is necessary to hold dpm_list locked throughout all that or else
* we may end up suspending with a wrong ordering of it.
*/
device_reorder_to_tail(consumer, NULL);
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));
out:
device_pm_unlock();
device_links_write_unlock();
return link;
}
EXPORT_SYMBOL_GPL(device_link_add);
static void device_link_free(struct device_link *link)
{
put_device(link->consumer);
put_device(link->supplier);
kfree(link);
}
#ifdef CONFIG_SRCU
static void __device_link_free_srcu(struct rcu_head *rhead)
{
device_link_free(container_of(rhead, struct device_link, rcu_head));
}
static void __device_link_del(struct device_link *link)
{
dev_info(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);
list_del_rcu(&link->s_node);
list_del_rcu(&link->c_node);
call_srcu(&device_links_srcu, &link->rcu_head, __device_link_free_srcu);
}
#else /* !CONFIG_SRCU */
static void __device_link_del(struct device_link *link)
{
dev_info(link->consumer, "Dropping the link to %s\n",
dev_name(link->supplier));
list_del(&link->s_node);
list_del(&link->c_node);
device_link_free(link);
}
#endif /* !CONFIG_SRCU */
/**
* device_link_del - Delete a link between two devices.
* @link: Device link to delete.
*
* The caller must ensure proper synchronization of this function with runtime
* PM.
*/
void device_link_del(struct device_link *link)
{
device_links_write_lock();
device_pm_lock();
__device_link_del(link);
device_pm_unlock();
device_links_write_unlock();
}
EXPORT_SYMBOL_GPL(device_link_del);
static void device_links_missing_supplier(struct device *dev)
{
struct device_link *link;
list_for_each_entry(link, &dev->links.suppliers, c_node)
if (link->status == DL_STATE_CONSUMER_PROBE)
WRITE_ONCE(link->status, DL_STATE_AVAILABLE);
}
/**
* device_links_check_suppliers - Check presence of supplier drivers.
* @dev: Consumer device.
*
* Check links from this device to any suppliers. Walk the list of the device's
* links to suppliers and see if all of them are available. If not, simply
* return -EPROBE_DEFER.
*
* We need to guarantee that the supplier will not go away after the check has
* been positive here. It only can go away in __device_release_driver() and
* that function checks the device's links to consumers. This means we need to
* mark the link as "consumer probe in progress" to make the supplier removal
* wait for us to complete (or bad things may happen).
*
* Links with the DL_FLAG_STATELESS flag set are ignored.
*/
int device_links_check_suppliers(struct device *dev)
{
struct device_link *link;
int ret = 0;
device_links_write_lock();
list_for_each_entry(link, &dev->links.suppliers, c_node) {
if (link->flags & DL_FLAG_STATELESS)
continue;
if (link->status != DL_STATE_AVAILABLE) {
device_links_missing_supplier(dev);
ret = -EPROBE_DEFER;
break;
}
WRITE_ONCE(link->status, DL_STATE_CONSUMER_PROBE);
}
dev->links.status = DL_DEV_PROBING;
device_links_write_unlock();
return ret;
}
/**
* device_links_driver_bound - Update device links after probing its driver.
* @dev: Device to update the links for.
*
* The probe has been successful, so update links from this device to any
* consumers by changing their status to "available".
*
* Also change the status of @dev's links to suppliers to "active".
*
* Links with the DL_FLAG_STATELESS flag set are ignored.
*/
void device_links_driver_bound(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;
WARN_ON(link->status != DL_STATE_DORMANT);
WRITE_ONCE(link->status, DL_STATE_AVAILABLE);
}
list_for_each_entry(link, &dev->links.suppliers, c_node) {
if (link->flags & DL_FLAG_STATELESS)
continue;
WARN_ON(link->status != DL_STATE_CONSUMER_PROBE);
WRITE_ONCE(link->status, DL_STATE_ACTIVE);
}
dev->links.status = DL_DEV_DRIVER_BOUND;
device_links_write_unlock();
}
/**
* __device_links_no_driver - Update links of a device without a driver.
* @dev: Device without a drvier.
*
* Delete all non-persistent links from this device to any suppliers.
*
* Persistent links stay around, but their status is changed to "available",
* unless they already are in the "supplier unbind in progress" state in which
* case they need not be updated.
*
* Links with the DL_FLAG_STATELESS flag set are ignored.
*/
static void __device_links_no_driver(struct device *dev)
{
struct device_link *link, *ln;
list_for_each_entry_safe_reverse(link, ln, &dev->links.suppliers, c_node) {
if (link->flags & DL_FLAG_STATELESS)
continue;
if (link->flags & DL_FLAG_AUTOREMOVE)
__device_link_del(link);
else if (link->status != DL_STATE_SUPPLIER_UNBIND)
WRITE_ONCE(link->status, DL_STATE_AVAILABLE);
}
dev->links.status = DL_DEV_NO_DRIVER;
}
void device_links_no_driver(struct device *dev)
{
device_links_write_lock();
__device_links_no_driver(dev);
device_links_write_unlock();
}
/**
* device_links_driver_cleanup - Update links after driver removal.
* @dev: Device whose driver has just gone away.
*
* Update links to consumers for @dev by changing their status to "dormant" 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_driver_cleanup(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;
WARN_ON(link->flags & DL_FLAG_AUTOREMOVE);
WARN_ON(link->status != DL_STATE_SUPPLIER_UNBIND);
WRITE_ONCE(link->status, DL_STATE_DORMANT);
}
__device_links_no_driver(dev);
device_links_write_unlock();
}
/**
* device_links_busy - Check if there are any busy links to consumers.
* @dev: Device to check.
*
* Check each consumer of the device and return 'true' if its link's status
* is one of "consumer probe" or "active" (meaning that the given consumer is
* probing right now or its driver is present). Otherwise, change the link
* state to "supplier unbind" to prevent the consumer from being probed
* successfully going forward.
*
* Return 'false' if there are no probing or active consumers.
*
* Links with the DL_FLAG_STATELESS flag set are ignored.
*/
bool device_links_busy(struct device *dev)
{
struct device_link *link;
bool ret = false;
device_links_write_lock();
list_for_each_entry(link, &dev->links.consumers, s_node) {
if (link->flags & DL_FLAG_STATELESS)
continue;
if (link->status == DL_STATE_CONSUMER_PROBE
|| link->status == DL_STATE_ACTIVE) {
ret = true;
break;
}
WRITE_ONCE(link->status, DL_STATE_SUPPLIER_UNBIND);
}
dev->links.status = DL_DEV_UNBINDING;
device_links_write_unlock();
return ret;
}
/**
* device_links_unbind_consumers - Force unbind consumers of the given device.
* @dev: Device to unbind the consumers of.
*
* Walk the list of links to consumers for @dev and if any of them is in the
* "consumer probe" state, wait for all device probes in progress to complete
* and start over.
*
* If that's not the case, change the status of the link to "supplier unbind"
* and check if the link was in the "active" state. If so, force the consumer
* driver to unbind and start over (the consumer will not re-probe as we have
* changed the state of the link already).
*
* Links with the DL_FLAG_STATELESS flag set are ignored.
*/
void device_links_unbind_consumers(struct device *dev)
{
struct device_link *link;
start:
device_links_write_lock();
list_for_each_entry(link, &dev->links.consumers, s_node) {
enum device_link_state status;
if (link->flags & DL_FLAG_STATELESS)
continue;
status = link->status;
if (status == DL_STATE_CONSUMER_PROBE) {
device_links_write_unlock();
wait_for_device_probe();
goto start;
}
WRITE_ONCE(link->status, DL_STATE_SUPPLIER_UNBIND);
if (status == DL_STATE_ACTIVE) {
struct device *consumer = link->consumer;
get_device(consumer);
device_links_write_unlock();
device_release_driver_internal(consumer, NULL,
consumer->parent);
put_device(consumer);
goto start;
}
}
device_links_write_unlock();
}
/**
* device_links_purge - Delete existing links to other devices.
* @dev: Target device.
*/
static void device_links_purge(struct device *dev)
{
struct device_link *link, *ln;
/*
* Delete all of the remaining links from this device to any other
* devices (either consumers or suppliers).
*/
device_links_write_lock();
list_for_each_entry_safe_reverse(link, ln, &dev->links.suppliers, c_node) {
WARN_ON(link->status == DL_STATE_ACTIVE);
__device_link_del(link);
}
list_for_each_entry_safe_reverse(link, ln, &dev->links.consumers, s_node) {
WARN_ON(link->status != DL_STATE_DORMANT &&
link->status != DL_STATE_NONE);
__device_link_del(link);
}
device_links_write_unlock();
}
/* Device links support end. */
int (*platform_notify)(struct device *dev) = NULL;
int (*platform_notify_remove)(struct device *dev) = NULL;
static struct kobject *dev_kobj;
@ -494,8 +1060,14 @@ static int device_add_attrs(struct device *dev)
goto err_remove_dev_groups;
}
error = device_create_file(dev, &dev_attr_deferred_probe);
if (error)
goto err_remove_online;
return 0;
err_remove_online:
device_remove_file(dev, &dev_attr_online);
err_remove_dev_groups:
device_remove_groups(dev, dev->groups);
err_remove_type_groups:
@ -513,6 +1085,7 @@ static void device_remove_attrs(struct device *dev)
struct class *class = dev->class;
const struct device_type *type = dev->type;
device_remove_file(dev, &dev_attr_deferred_probe);
device_remove_file(dev, &dev_attr_online);
device_remove_groups(dev, dev->groups);
@ -711,6 +1284,9 @@ void device_initialize(struct device *dev)
#ifdef CONFIG_GENERIC_MSI_IRQ
INIT_LIST_HEAD(&dev->msi_list);
#endif
INIT_LIST_HEAD(&dev->links.consumers);
INIT_LIST_HEAD(&dev->links.suppliers);
dev->links.status = DL_DEV_NO_DRIVER;
}
EXPORT_SYMBOL_GPL(device_initialize);
@ -1258,6 +1834,8 @@ void device_del(struct device *dev)
if (dev->bus)
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
BUS_NOTIFY_DEL_DEVICE, dev);
device_links_purge(dev);
dpm_sysfs_remove(dev);
if (parent)
klist_del(&dev->p->knode_parent);

79
drivers/base/dd.c
View file

@ -53,6 +53,19 @@ static LIST_HEAD(deferred_probe_pending_list);
static LIST_HEAD(deferred_probe_active_list);
static atomic_t deferred_trigger_count = ATOMIC_INIT(0);
static ssize_t deferred_probe_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
bool value;
mutex_lock(&deferred_probe_mutex);
value = !list_empty(&dev->p->deferred_probe);
mutex_unlock(&deferred_probe_mutex);
return sprintf(buf, "%d\n", value);
}
DEVICE_ATTR_RO(deferred_probe);
/*
* In some cases, like suspend to RAM or hibernation, It might be reasonable
* to prohibit probing of devices as it could be unsafe.
@ -244,6 +257,7 @@ static void driver_bound(struct device *dev)
__func__, dev_name(dev));
klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices);
device_links_driver_bound(dev);
device_pm_check_callbacks(dev);
@ -338,6 +352,10 @@ static int really_probe(struct device *dev, struct device_driver *drv)
return ret;
}
ret = device_links_check_suppliers(dev);
if (ret)
return ret;
atomic_inc(&probe_count);
pr_debug("bus: '%s': %s: probing driver %s with device %s\n",
drv->bus->name, __func__, drv->name, dev_name(dev));
@ -416,6 +434,7 @@ probe_failed:
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
BUS_NOTIFY_DRIVER_NOT_BOUND, dev);
pinctrl_bind_failed:
device_links_no_driver(dev);
devres_release_all(dev);
driver_sysfs_remove(dev);
dev->driver = NULL;
@ -508,6 +527,7 @@ int driver_probe_device(struct device_driver *drv, struct device *dev)
pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
drv->bus->name, __func__, dev_name(dev), drv->name);
pm_runtime_get_suppliers(dev);
if (dev->parent)
pm_runtime_get_sync(dev->parent);
@ -518,6 +538,7 @@ int driver_probe_device(struct device_driver *drv, struct device *dev)
if (dev->parent)
pm_runtime_put(dev->parent);
pm_runtime_put_suppliers(dev);
return ret;
}
@ -772,7 +793,7 @@ EXPORT_SYMBOL_GPL(driver_attach);
* __device_release_driver() must be called with @dev lock held.
* When called for a USB interface, @dev->parent lock must be held as well.
*/
static void __device_release_driver(struct device *dev)
static void __device_release_driver(struct device *dev, struct device *parent)
{
struct device_driver *drv;
@ -781,7 +802,27 @@ static void __device_release_driver(struct device *dev)
if (driver_allows_async_probing(drv))
async_synchronize_full();
while (device_links_busy(dev)) {
device_unlock(dev);
if (parent)
device_unlock(parent);
device_links_unbind_consumers(dev);
if (parent)
device_lock(parent);
device_lock(dev);
/*
* A concurrent invocation of the same function might
* have released the driver successfully while this one
* was waiting, so check for that.
*/
if (dev->driver != drv)
return;
}
pm_runtime_get_sync(dev);
pm_runtime_clean_up_links(dev);
driver_sysfs_remove(dev);
@ -796,6 +837,8 @@ static void __device_release_driver(struct device *dev)
dev->bus->remove(dev);
else if (drv->remove)
drv->remove(dev);
device_links_driver_cleanup(dev);
devres_release_all(dev);
dev->driver = NULL;
dev_set_drvdata(dev, NULL);
@ -812,12 +855,32 @@ static void __device_release_driver(struct device *dev)
}
}
void device_release_driver_internal(struct device *dev,
struct device_driver *drv,
struct device *parent)
{
if (parent)
device_lock(parent);
device_lock(dev);
if (!drv || drv == dev->driver)
__device_release_driver(dev, parent);
device_unlock(dev);
if (parent)
device_unlock(parent);
}
/**
* device_release_driver - manually detach device from driver.
* @dev: device.
*
* Manually detach device from driver.
* When called for a USB interface, @dev->parent lock must be held.
*
* If this function is to be called with @dev->parent lock held, ensure that
* the device's consumers are unbound in advance or that their locks can be
* acquired under the @dev->parent lock.
*/
void device_release_driver(struct device *dev)
{
@ -826,9 +889,7 @@ void device_release_driver(struct device *dev)
* within their ->remove callback for the same device, they
* will deadlock right here.
*/
device_lock(dev);
__device_release_driver(dev);
device_unlock(dev);
device_release_driver_internal(dev, NULL, NULL);
}
EXPORT_SYMBOL_GPL(device_release_driver);
@ -853,15 +914,7 @@ void driver_detach(struct device_driver *drv)
dev = dev_prv->device;
get_device(dev);
spin_unlock(&drv->p->klist_devices.k_lock);
if (dev->parent) /* Needed for USB */
device_lock(dev->parent);
device_lock(dev);
if (dev->driver == drv)
__device_release_driver(dev);
device_unlock(dev);
if (dev->parent)
device_unlock(dev->parent);
device_release_driver_internal(dev, drv, dev->parent);
put_device(dev);
}
}

10
drivers/base/devcoredump.c
View file

@ -160,18 +160,20 @@ static ssize_t disabled_store(struct class *class, struct class_attribute *attr,
return count;
}
static CLASS_ATTR_RW(disabled);
static struct class_attribute devcd_class_attrs[] = {
__ATTR_RW(disabled),
__ATTR_NULL
static struct attribute *devcd_class_attrs[] = {
&class_attr_disabled.attr,
NULL,
};
ATTRIBUTE_GROUPS(devcd_class);
static struct class devcd_class = {
.name = "devcoredump",
.owner = THIS_MODULE,
.dev_release = devcd_dev_release,
.dev_groups = devcd_dev_groups,
.class_attrs = devcd_class_attrs,
.class_groups = devcd_class_groups,
};
static ssize_t devcd_readv(char *buffer, loff_t offset, size_t count,

4
drivers/base/dma-mapping.c
View file

@ -108,13 +108,13 @@ void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
EXPORT_SYMBOL(dmam_free_coherent);
/**
* dmam_alloc_non_coherent - Managed dma_alloc_non_coherent()
* dmam_alloc_non_coherent - Managed dma_alloc_noncoherent()
* @dev: Device to allocate non_coherent memory for
* @size: Size of allocation
* @dma_handle: Out argument for allocated DMA handle
* @gfp: Allocation flags
*
* Managed dma_alloc_non_coherent(). Memory allocated using this
* Managed dma_alloc_noncoherent(). Memory allocated using this
* function will be automatically released on driver detach.
*
* RETURNS:

178
drivers/base/firmware_class.c
View file

@ -30,6 +30,7 @@
#include <linux/syscore_ops.h>
#include <linux/reboot.h>
#include <linux/security.h>
#include <linux/swait.h>
#include <generated/utsrelease.h>
@ -91,10 +92,11 @@ static inline bool fw_is_builtin_firmware(const struct firmware *fw)
}
#endif
enum {
enum fw_status {
FW_STATUS_UNKNOWN,
FW_STATUS_LOADING,
FW_STATUS_DONE,
FW_STATUS_ABORT,
FW_STATUS_ABORTED,
};
static int loading_timeout = 60; /* In seconds */
@ -104,6 +106,82 @@ static inline long firmware_loading_timeout(void)
return loading_timeout > 0 ? loading_timeout * HZ : MAX_JIFFY_OFFSET;
}
/*
* Concurrent request_firmware() for the same firmware need to be
* serialized. struct fw_state is simple state machine which hold the
* state of the firmware loading.
*/
struct fw_state {
struct swait_queue_head wq;
enum fw_status status;
};
static void fw_state_init(struct fw_state *fw_st)
{
init_swait_queue_head(&fw_st->wq);
fw_st->status = FW_STATUS_UNKNOWN;
}
static inline bool __fw_state_is_done(enum fw_status status)
{
return status == FW_STATUS_DONE || status == FW_STATUS_ABORTED;
}
static int __fw_state_wait_common(struct fw_state *fw_st, long timeout)
{
long ret;
ret = swait_event_interruptible_timeout(fw_st->wq,
__fw_state_is_done(READ_ONCE(fw_st->status)),
timeout);
if (ret != 0 && fw_st->status == FW_STATUS_ABORTED)
return -ENOENT;
if (!ret)
return -ETIMEDOUT;
return ret < 0 ? ret : 0;
}
static void __fw_state_set(struct fw_state *fw_st,
enum fw_status status)
{
WRITE_ONCE(fw_st->status, status);
if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED)
swake_up(&fw_st->wq);
}
#define fw_state_start(fw_st) \
__fw_state_set(fw_st, FW_STATUS_LOADING)
#define fw_state_done(fw_st) \
__fw_state_set(fw_st, FW_STATUS_DONE)
#define fw_state_wait(fw_st) \
__fw_state_wait_common(fw_st, MAX_SCHEDULE_TIMEOUT)
#ifndef CONFIG_FW_LOADER_USER_HELPER
#define fw_state_is_aborted(fw_st) false
#else /* CONFIG_FW_LOADER_USER_HELPER */
static int __fw_state_check(struct fw_state *fw_st, enum fw_status status)
{
return fw_st->status == status;
}
#define fw_state_aborted(fw_st) \
__fw_state_set(fw_st, FW_STATUS_ABORTED)
#define fw_state_is_done(fw_st) \
__fw_state_check(fw_st, FW_STATUS_DONE)
#define fw_state_is_loading(fw_st) \
__fw_state_check(fw_st, FW_STATUS_LOADING)
#define fw_state_is_aborted(fw_st) \
__fw_state_check(fw_st, FW_STATUS_ABORTED)
#define fw_state_wait_timeout(fw_st, timeout) \
__fw_state_wait_common(fw_st, timeout)
#endif /* CONFIG_FW_LOADER_USER_HELPER */
/* firmware behavior options */
#define FW_OPT_UEVENT (1U << 0)
#define FW_OPT_NOWAIT (1U << 1)
@ -145,9 +223,8 @@ struct firmware_cache {
struct firmware_buf {
struct kref ref;
struct list_head list;
struct completion completion;
struct firmware_cache *fwc;
unsigned long status;
struct fw_state fw_st;
void *data;
size_t size;
size_t allocated_size;
@ -205,7 +282,7 @@ static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
buf->fwc = fwc;
buf->data = dbuf;
buf->allocated_size = size;
init_completion(&buf->completion);
fw_state_init(&buf->fw_st);
#ifdef CONFIG_FW_LOADER_USER_HELPER
INIT_LIST_HEAD(&buf->pending_list);
#endif
@ -305,15 +382,6 @@ static const char * const fw_path[] = {
module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
static void fw_finish_direct_load(struct device *device,
struct firmware_buf *buf)
{
mutex_lock(&fw_lock);
set_bit(FW_STATUS_DONE, &buf->status);
complete_all(&buf->completion);
mutex_unlock(&fw_lock);
}
static int
fw_get_filesystem_firmware(struct device *device, struct firmware_buf *buf)
{
@ -360,7 +428,7 @@ fw_get_filesystem_firmware(struct device *device, struct firmware_buf *buf)
}
dev_dbg(device, "direct-loading %s\n", buf->fw_id);
buf->size = size;
fw_finish_direct_load(device, buf);
fw_state_done(&buf->fw_st);
break;
}
__putname(path);
@ -478,12 +546,11 @@ static void __fw_load_abort(struct firmware_buf *buf)
* There is a small window in which user can write to 'loading'
* between loading done and disappearance of 'loading'
*/
if (test_bit(FW_STATUS_DONE, &buf->status))
if (fw_state_is_done(&buf->fw_st))
return;
list_del_init(&buf->pending_list);
set_bit(FW_STATUS_ABORT, &buf->status);
complete_all(&buf->completion);
fw_state_aborted(&buf->fw_st);
}
static void fw_load_abort(struct firmware_priv *fw_priv)
@ -496,9 +563,6 @@ static void fw_load_abort(struct firmware_priv *fw_priv)
fw_priv->buf = NULL;
}
#define is_fw_load_aborted(buf) \
test_bit(FW_STATUS_ABORT, &(buf)->status)
static LIST_HEAD(pending_fw_head);
/* reboot notifier for avoid deadlock with usermode_lock */
@ -546,11 +610,13 @@ static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
return count;
}
static CLASS_ATTR_RW(timeout);
static struct class_attribute firmware_class_attrs[] = {
__ATTR_RW(timeout),
__ATTR_NULL
static struct attribute *firmware_class_attrs[] = {
&class_attr_timeout.attr,
NULL,
};
ATTRIBUTE_GROUPS(firmware_class);
static void fw_dev_release(struct device *dev)
{
@ -585,7 +651,7 @@ static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
static struct class firmware_class = {
.name = "firmware",
.class_attrs = firmware_class_attrs,
.class_groups = firmware_class_groups,
.dev_uevent = firmware_uevent,
.dev_release = fw_dev_release,
};
@ -598,7 +664,7 @@ static ssize_t firmware_loading_show(struct device *dev,
mutex_lock(&fw_lock);
if (fw_priv->buf)
loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
loading = fw_state_is_loading(&fw_priv->buf->fw_st);
mutex_unlock(&fw_lock);
return sprintf(buf, "%d\n", loading);
@ -653,23 +719,20 @@ static ssize_t firmware_loading_store(struct device *dev,
switch (loading) {
case 1:
/* discarding any previous partial load */
if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
if (!fw_state_is_done(&fw_buf->fw_st)) {
for (i = 0; i < fw_buf->nr_pages; i++)
__free_page(fw_buf->pages[i]);
vfree(fw_buf->pages);
fw_buf->pages = NULL;
fw_buf->page_array_size = 0;
fw_buf->nr_pages = 0;
set_bit(FW_STATUS_LOADING, &fw_buf->status);
fw_state_start(&fw_buf->fw_st);
}
break;
case 0:
if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
if (fw_state_is_loading(&fw_buf->fw_st)) {
int rc;
set_bit(FW_STATUS_DONE, &fw_buf->status);
clear_bit(FW_STATUS_LOADING, &fw_buf->status);
/*
* Several loading requests may be pending on
* one same firmware buf, so let all requests
@ -691,10 +754,11 @@ static ssize_t firmware_loading_store(struct device *dev,
*/
list_del_init(&fw_buf->pending_list);
if (rc) {
set_bit(FW_STATUS_ABORT, &fw_buf->status);
fw_state_aborted(&fw_buf->fw_st);
written = rc;
} else {
fw_state_done(&fw_buf->fw_st);
}
complete_all(&fw_buf->completion);
break;
}
/* fallthrough */
@ -755,7 +819,7 @@ static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
mutex_lock(&fw_lock);
buf = fw_priv->buf;
if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
if (!buf || fw_state_is_done(&buf->fw_st)) {
ret_count = -ENODEV;
goto out;
}
@ -842,7 +906,7 @@ static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
mutex_lock(&fw_lock);
buf = fw_priv->buf;
if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
if (!buf || fw_state_is_done(&buf->fw_st)) {
retval = -ENODEV;
goto out;
}
@ -955,17 +1019,14 @@ static int _request_firmware_load(struct firmware_priv *fw_priv,
timeout = MAX_JIFFY_OFFSET;
}
retval = wait_for_completion_interruptible_timeout(&buf->completion,
timeout);
if (retval == -ERESTARTSYS || !retval) {
retval = fw_state_wait_timeout(&buf->fw_st, timeout);
if (retval < 0) {
mutex_lock(&fw_lock);
fw_load_abort(fw_priv);
mutex_unlock(&fw_lock);
} else if (retval > 0) {
retval = 0;
}
if (is_fw_load_aborted(buf))
if (fw_state_is_aborted(&buf->fw_st))
retval = -EAGAIN;
else if (buf->is_paged_buf && !buf->data)
retval = -ENOMEM;
@ -1015,35 +1076,12 @@ fw_load_from_user_helper(struct firmware *firmware, const char *name,
return -ENOENT;
}
/* No abort during direct loading */
#define is_fw_load_aborted(buf) false
#ifdef CONFIG_PM_SLEEP
static inline void kill_requests_without_uevent(void) { }
#endif
#endif /* CONFIG_FW_LOADER_USER_HELPER */
/* wait until the shared firmware_buf becomes ready (or error) */
static int sync_cached_firmware_buf(struct firmware_buf *buf)
{
int ret = 0;
mutex_lock(&fw_lock);
while (!test_bit(FW_STATUS_DONE, &buf->status)) {
if (is_fw_load_aborted(buf)) {
ret = -ENOENT;
break;
}
mutex_unlock(&fw_lock);
ret = wait_for_completion_interruptible(&buf->completion);
mutex_lock(&fw_lock);
}
mutex_unlock(&fw_lock);
return ret;
}
/* prepare firmware and firmware_buf structs;
* return 0 if a firmware is already assigned, 1 if need to load one,
* or a negative error code
@ -1077,7 +1115,7 @@ _request_firmware_prepare(struct firmware **firmware_p, const char *name,
firmware->priv = buf;
if (ret > 0) {
ret = sync_cached_firmware_buf(buf);
ret = fw_state_wait(&buf->fw_st);
if (!ret) {
fw_set_page_data(buf, firmware);
return 0; /* assigned */
@ -1095,7 +1133,7 @@ static int assign_firmware_buf(struct firmware *fw, struct device *device,
struct firmware_buf *buf = fw->priv;
mutex_lock(&fw_lock);
if (!buf->size || is_fw_load_aborted(buf)) {
if (!buf->size || fw_state_is_aborted(&buf->fw_st)) {
mutex_unlock(&fw_lock);
return -ENOENT;
}
@ -1345,9 +1383,9 @@ static void request_firmware_work_func(struct work_struct *work)
*
* Asynchronous variant of request_firmware() for user contexts:
* - sleep for as small periods as possible since it may
* increase kernel boot time of built-in device drivers
* requesting firmware in their ->probe() methods, if
* @gfp is GFP_KERNEL.
* increase kernel boot time of built-in device drivers
* requesting firmware in their ->probe() methods, if
* @gfp is GFP_KERNEL.
*
* - can't sleep at all if @gfp is GFP_ATOMIC.
**/

2
drivers/base/memory.c
View file

@ -226,11 +226,9 @@ memory_block_action(unsigned long phys_index, unsigned long action, int online_t
{
unsigned long start_pfn;
unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
struct page *first_page;
int ret;
start_pfn = section_nr_to_pfn(phys_index);
first_page = pfn_to_page(start_pfn);
switch (action) {
case MEM_ONLINE:

87
drivers/base/power/main.c
View file

@ -131,6 +131,7 @@ void device_pm_add(struct device *dev)
dev_warn(dev, "parent %s should not be sleeping\n",
dev_name(dev->parent));
list_add_tail(&dev->power.entry, &dpm_list);
dev->power.in_dpm_list = true;
mutex_unlock(&dpm_list_mtx);
}
@ -145,6 +146,7 @@ void device_pm_remove(struct device *dev)
complete_all(&dev->power.completion);
mutex_lock(&dpm_list_mtx);
list_del_init(&dev->power.entry);
dev->power.in_dpm_list = false;
mutex_unlock(&dpm_list_mtx);
device_wakeup_disable(dev);
pm_runtime_remove(dev);
@ -244,6 +246,62 @@ static void dpm_wait_for_children(struct device *dev, bool async)
device_for_each_child(dev, &async, dpm_wait_fn);
}
static void dpm_wait_for_suppliers(struct device *dev, bool async)
{
struct device_link *link;
int idx;
idx = device_links_read_lock();
/*
* If the supplier goes away right after we've checked the link to it,
* we'll wait for its completion to change the state, but that's fine,
* because the only things that will block as a result are the SRCU
* callbacks freeing the link objects for the links in the list we're
* walking.
*/
list_for_each_entry_rcu(link, &dev->links.suppliers, c_node)
if (READ_ONCE(link->status) != DL_STATE_DORMANT)
dpm_wait(link->supplier, async);
device_links_read_unlock(idx);
}
static void dpm_wait_for_superior(struct device *dev, bool async)
{
dpm_wait(dev->parent, async);
dpm_wait_for_suppliers(dev, async);
}
static void dpm_wait_for_consumers(struct device *dev, bool async)
{
struct device_link *link;
int idx;
idx = device_links_read_lock();
/*
* The status of a device link can only be changed from "dormant" by a
* probe, but that cannot happen during system suspend/resume. In
* theory it can change to "dormant" at that time, but then it is
* reasonable to wait for the target device anyway (eg. if it goes
* away, it's better to wait for it to go away completely and then
* continue instead of trying to continue in parallel with its
* unregistration).
*/
list_for_each_entry_rcu(link, &dev->links.consumers, s_node)
if (READ_ONCE(link->status) != DL_STATE_DORMANT)
dpm_wait(link->consumer, async);
device_links_read_unlock(idx);
}
static void dpm_wait_for_subordinate(struct device *dev, bool async)
{
dpm_wait_for_children(dev, async);
dpm_wait_for_consumers(dev, async);
}
/**
* pm_op - Return the PM operation appropriate for given PM event.
* @ops: PM operations to choose from.
@ -488,7 +546,7 @@ static int device_resume_noirq(struct device *dev, pm_message_t state, bool asyn
if (!dev->power.is_noirq_suspended)
goto Out;
dpm_wait(dev->parent, async);
dpm_wait_for_superior(dev, async);
if (dev->pm_domain) {
info = "noirq power domain ";
@ -618,7 +676,7 @@ static int device_resume_early(struct device *dev, pm_message_t state, bool asyn
if (!dev->power.is_late_suspended)
goto Out;
dpm_wait(dev->parent, async);
dpm_wait_for_superior(dev, async);
if (dev->pm_domain) {
info = "early power domain ";
@ -750,7 +808,7 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
goto Complete;
}
dpm_wait(dev->parent, async);
dpm_wait_for_superior(dev, async);
dpm_watchdog_set(&wd, dev);
device_lock(dev);
@ -1027,7 +1085,7 @@ static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool a
TRACE_DEVICE(dev);
TRACE_SUSPEND(0);
dpm_wait_for_children(dev, async);
dpm_wait_for_subordinate(dev, async);
if (async_error)
goto Complete;
@ -1174,7 +1232,7 @@ static int __device_suspend_late(struct device *dev, pm_message_t state, bool as
__pm_runtime_disable(dev, false);
dpm_wait_for_children(dev, async);
dpm_wait_for_subordinate(dev, async);
if (async_error)
goto Complete;
@ -1342,6 +1400,22 @@ static int legacy_suspend(struct device *dev, pm_message_t state,
return error;
}
static void dpm_clear_suppliers_direct_complete(struct device *dev)
{
struct device_link *link;
int idx;
idx = device_links_read_lock();
list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) {
spin_lock_irq(&link->supplier->power.lock);
link->supplier->power.direct_complete = false;
spin_unlock_irq(&link->supplier->power.lock);
}
device_links_read_unlock(idx);
}
/**
* device_suspend - Execute "suspend" callbacks for given device.
* @dev: Device to handle.
@ -1358,7 +1432,7 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
TRACE_DEVICE(dev);
TRACE_SUSPEND(0);
dpm_wait_for_children(dev, async);
dpm_wait_for_subordinate(dev, async);
if (async_error)
goto Complete;
@ -1454,6 +1528,7 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
spin_unlock_irq(&parent->power.lock);
}
dpm_clear_suppliers_direct_complete(dev);
}
device_unlock(dev);

10
drivers/base/power/power.h
View file

@ -144,6 +144,11 @@ extern void device_pm_move_after(struct device *, struct device *);
extern void device_pm_move_last(struct device *);
extern void device_pm_check_callbacks(struct device *dev);
static inline bool device_pm_initialized(struct device *dev)
{
return dev->power.in_dpm_list;
}
#else /* !CONFIG_PM_SLEEP */
static inline void device_pm_sleep_init(struct device *dev) {}
@ -163,6 +168,11 @@ static inline void device_pm_move_last(struct device *dev) {}
static inline void device_pm_check_callbacks(struct device *dev) {}
static inline bool device_pm_initialized(struct device *dev)
{
return device_is_registered(dev);
}
#endif /* !CONFIG_PM_SLEEP */
static inline void device_pm_init(struct device *dev)

174
drivers/base/power/runtime.c
View file

@ -12,6 +12,8 @@
#include <linux/pm_runtime.h>
#include <linux/pm_wakeirq.h>
#include <trace/events/rpm.h>
#include "../base.h"
#include "power.h"
typedef int (*pm_callback_t)(struct device *);
@ -259,6 +261,42 @@ static int rpm_check_suspend_allowed(struct device *dev)
return retval;
}
static int rpm_get_suppliers(struct device *dev)
{
struct device_link *link;
list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) {
int retval;
if (!(link->flags & DL_FLAG_PM_RUNTIME))
continue;
if (READ_ONCE(link->status) == DL_STATE_SUPPLIER_UNBIND ||
link->rpm_active)
continue;
retval = pm_runtime_get_sync(link->supplier);
if (retval < 0) {
pm_runtime_put_noidle(link->supplier);
return retval;
}
link->rpm_active = true;
}
return 0;
}
static void rpm_put_suppliers(struct device *dev)
{
struct device_link *link;
list_for_each_entry_rcu(link, &dev->links.suppliers, c_node)
if (link->rpm_active &&
READ_ONCE(link->status) != DL_STATE_SUPPLIER_UNBIND) {
pm_runtime_put(link->supplier);
link->rpm_active = false;
}
}
/**
* __rpm_callback - Run a given runtime PM callback for a given device.
* @cb: Runtime PM callback to run.
@ -267,19 +305,57 @@ static int rpm_check_suspend_allowed(struct device *dev)
static int __rpm_callback(int (*cb)(struct device *), struct device *dev)
__releases(&dev->power.lock) __acquires(&dev->power.lock)
{
int retval;
int retval, idx;
bool use_links = dev->power.links_count > 0;
if (dev->power.irq_safe)
if (dev->power.irq_safe) {
spin_unlock(&dev->power.lock);
else
} else {
spin_unlock_irq(&dev->power.lock);
/*
* Resume suppliers if necessary.
*
* The device's runtime PM status cannot change until this
* routine returns, so it is safe to read the status outside of
* the lock.
*/
if (use_links && dev->power.runtime_status == RPM_RESUMING) {
idx = device_links_read_lock();
retval = rpm_get_suppliers(dev);
if (retval)
goto fail;
device_links_read_unlock(idx);
}
}
retval = cb(dev);
if (dev->power.irq_safe)
if (dev->power.irq_safe) {
spin_lock(&dev->power.lock);
else
} else {
/*
* If the device is suspending and the callback has returned
* success, drop the usage counters of the suppliers that have
* been reference counted on its resume.
*
* Do that if resume fails too.
*/
if (use_links
&& ((dev->power.runtime_status == RPM_SUSPENDING && !retval)
|| (dev->power.runtime_status == RPM_RESUMING && retval))) {
idx = device_links_read_lock();
fail:
rpm_put_suppliers(dev);
device_links_read_unlock(idx);
}
spin_lock_irq(&dev->power.lock);
}
return retval;
}
@ -1457,6 +1533,94 @@ void pm_runtime_remove(struct device *dev)
pm_runtime_reinit(dev);
}
/**
* pm_runtime_clean_up_links - Prepare links to consumers for driver removal.
* @dev: Device whose driver is going to be removed.
*
* Check links from this device to any consumers and if any of them have active
* runtime PM references to the device, drop the usage counter of the device
* (once per link).
*
* Links with the DL_FLAG_STATELESS flag set are ignored.
*
* Since the device is guaranteed to be runtime-active at the point this is
* called, nothing else needs to be done here.
*
* Moreover, this is called after device_links_busy() has returned 'false', so
* the status of each link is guaranteed to be DL_STATE_SUPPLIER_UNBIND and
* therefore rpm_active can't be manipulated concurrently.
*/
void pm_runtime_clean_up_links(struct device *dev)
{
struct device_link *link;
int idx;
idx = device_links_read_lock();
list_for_each_entry_rcu(link, &dev->links.consumers, s_node) {
if (link->flags & DL_FLAG_STATELESS)
continue;
if (link->rpm_active) {
pm_runtime_put_noidle(dev);
link->rpm_active = false;
}
}
device_links_read_unlock(idx);
}
/**
* pm_runtime_get_suppliers - Resume and reference-count supplier devices.
* @dev: Consumer device.
*/
void pm_runtime_get_suppliers(struct device *dev)
{
struct device_link *link;
int idx;
idx = device_links_read_lock();
list_for_each_entry_rcu(link, &dev->links.suppliers, c_node)
if (link->flags & DL_FLAG_PM_RUNTIME)
pm_runtime_get_sync(link->supplier);
device_links_read_unlock(idx);
}
/**
* pm_runtime_put_suppliers - Drop references to supplier devices.
* @dev: Consumer device.
*/
void pm_runtime_put_suppliers(struct device *dev)
{
struct device_link *link;
int idx;
idx = device_links_read_lock();
list_for_each_entry_rcu(link, &dev->links.suppliers, c_node)
if (link->flags & DL_FLAG_PM_RUNTIME)
pm_runtime_put(link->supplier);
device_links_read_unlock(idx);
}
void pm_runtime_new_link(struct device *dev)
{
spin_lock_irq(&dev->power.lock);
dev->power.links_count++;
spin_unlock_irq(&dev->power.lock);
}
void pm_runtime_drop_link(struct device *dev)
{
spin_lock_irq(&dev->power.lock);
WARN_ON(dev->power.links_count == 0);
dev->power.links_count--;
spin_unlock_irq(&dev->power.lock);
}
/**
* pm_runtime_force_suspend - Force a device into suspend state if needed.
* @dev: Device to suspend.

9
drivers/base/test/Kconfig Normal file
View file

@ -0,0 +1,9 @@
config TEST_ASYNC_DRIVER_PROBE
tristate "Build kernel module to test asynchronous driver probing"
depends on m
help
Enabling this option produces a kernel module that allows
testing asynchronous driver probing by the device core.
The module name will be test_async_driver_probe.ko
If unsure say N.

1
drivers/base/test/Makefile Normal file
View file

@ -0,0 +1 @@
obj-$(CONFIG_TEST_ASYNC_DRIVER_PROBE) += test_async_driver_probe.o

169
drivers/base/test/test_async_driver_probe.c Normal file
View file

@ -0,0 +1,169 @@
/*
* Copyright (C) 2014 Google, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/hrtimer.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/time.h>
#define TEST_PROBE_DELAY (5 * 1000) /* 5 sec */
#define TEST_PROBE_THRESHOLD (TEST_PROBE_DELAY / 2)
static int test_probe(struct platform_device *pdev)
{
dev_info(&pdev->dev, "sleeping for %d msecs in probe\n",
TEST_PROBE_DELAY);
msleep(TEST_PROBE_DELAY);
dev_info(&pdev->dev, "done sleeping\n");
return 0;
}
static struct platform_driver async_driver = {
.driver = {
.name = "test_async_driver",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
.probe = test_probe,
};
static struct platform_driver sync_driver = {
.driver = {
.name = "test_sync_driver",
.probe_type = PROBE_FORCE_SYNCHRONOUS,
},
.probe = test_probe,
};
static struct platform_device *async_dev_1, *async_dev_2;
static struct platform_device *sync_dev_1;
static int __init test_async_probe_init(void)
{
ktime_t calltime, delta;
unsigned long long duration;
int error;
pr_info("registering first asynchronous device...\n");
async_dev_1 = platform_device_register_simple("test_async_driver", 1,
NULL, 0);
if (IS_ERR(async_dev_1)) {
error = PTR_ERR(async_dev_1);
pr_err("failed to create async_dev_1: %d", error);
return error;
}
pr_info("registering asynchronous driver...\n");
calltime = ktime_get();
error = platform_driver_register(&async_driver);
if (error) {
pr_err("Failed to register async_driver: %d\n", error);
goto err_unregister_async_dev_1;
}
delta = ktime_sub(ktime_get(), calltime);
duration = (unsigned long long) ktime_to_ms(delta);
pr_info("registration took %lld msecs\n", duration);
if (duration > TEST_PROBE_THRESHOLD) {
pr_err("test failed: probe took too long\n");
error = -ETIMEDOUT;
goto err_unregister_async_driver;
}
pr_info("registering second asynchronous device...\n");
calltime = ktime_get();
async_dev_2 = platform_device_register_simple("test_async_driver", 2,
NULL, 0);
if (IS_ERR(async_dev_2)) {
error = PTR_ERR(async_dev_2);
pr_err("failed to create async_dev_2: %d", error);
goto err_unregister_async_driver;
}
delta = ktime_sub(ktime_get(), calltime);
duration = (unsigned long long) ktime_to_ms(delta);
pr_info("registration took %lld msecs\n", duration);
if (duration > TEST_PROBE_THRESHOLD) {
pr_err("test failed: probe took too long\n");
error = -ETIMEDOUT;
goto err_unregister_async_dev_2;
}
pr_info("registering synchronous driver...\n");
error = platform_driver_register(&sync_driver);
if (error) {
pr_err("Failed to register async_driver: %d\n", error);
goto err_unregister_async_dev_2;
}
pr_info("registering synchronous device...\n");
calltime = ktime_get();
sync_dev_1 = platform_device_register_simple("test_sync_driver", 1,
NULL, 0);
if (IS_ERR(sync_dev_1)) {
error = PTR_ERR(sync_dev_1);
pr_err("failed to create sync_dev_1: %d", error);
goto err_unregister_sync_driver;
}
delta = ktime_sub(ktime_get(), calltime);
duration = (unsigned long long) ktime_to_ms(delta);
pr_info("registration took %lld msecs\n", duration);
if (duration < TEST_PROBE_THRESHOLD) {
pr_err("test failed: probe was too quick\n");
error = -ETIMEDOUT;
goto err_unregister_sync_dev_1;
}
pr_info("completed successfully");
return 0;
err_unregister_sync_dev_1:
platform_device_unregister(sync_dev_1);
err_unregister_sync_driver:
platform_driver_unregister(&sync_driver);
err_unregister_async_dev_2:
platform_device_unregister(async_dev_2);
err_unregister_async_driver:
platform_driver_unregister(&async_driver);
err_unregister_async_dev_1:
platform_device_unregister(async_dev_1);
return error;
}
module_init(test_async_probe_init);
static void __exit test_async_probe_exit(void)
{
platform_driver_unregister(&async_driver);
platform_driver_unregister(&sync_driver);
platform_device_unregister(async_dev_1);
platform_device_unregister(async_dev_2);
platform_device_unregister(sync_dev_1);
}
module_exit(test_async_probe_exit);
MODULE_DESCRIPTION("Test module for asynchronous driver probing");
MODULE_AUTHOR("Dmitry Torokhov <[email protected]>");
MODULE_LICENSE("GPL");