From d2ccde1c8e90d38cee87a1b0309ad2827f3fd30d Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Mon, 11 Dec 2023 02:45:28 +0000
Subject: [PATCH] add boot partition size
---
kernel/drivers/base/core.c | 1524 ++++++++++++++++++++++++++++++++++++++++++++--------------
1 files changed, 1,160 insertions(+), 364 deletions(-)
diff --git a/kernel/drivers/base/core.c b/kernel/drivers/base/core.c
index ac565ae..23fce12 100644
--- a/kernel/drivers/base/core.c
+++ b/kernel/drivers/base/core.c
@@ -8,6 +8,7 @@
* Copyright (c) 2006 Novell, Inc.
*/
+#include <linux/acpi.h>
#include <linux/cpufreq.h>
#include <linux/device.h>
#include <linux/err.h>
@@ -25,6 +26,7 @@
#include <linux/pm_runtime.h>
#include <linux/netdevice.h>
#include <linux/sched/signal.h>
+#include <linux/sched/mm.h>
#include <linux/sysfs.h>
#include "base.h"
@@ -44,13 +46,122 @@
#endif
/* Device links support. */
-static LIST_HEAD(wait_for_suppliers);
-static DEFINE_MUTEX(wfs_lock);
static LIST_HEAD(deferred_sync);
static unsigned int defer_sync_state_count = 1;
-static unsigned int defer_fw_devlink_count;
-static LIST_HEAD(deferred_fw_devlink);
-static DEFINE_MUTEX(defer_fw_devlink_lock);
+static DEFINE_MUTEX(fwnode_link_lock);
+static bool fw_devlink_is_permissive(void);
+
+/**
+ * fwnode_link_add - Create a link between two fwnode_handles.
+ * @con: Consumer end of the link.
+ * @sup: Supplier end of the link.
+ *
+ * Create a fwnode link between fwnode handles @con and @sup. The fwnode link
+ * represents the detail that the firmware lists @sup fwnode as supplying a
+ * resource to @con.
+ *
+ * The driver core will use the fwnode link to create a device link between the
+ * two device objects corresponding to @con and @sup when they are created. The
+ * driver core will automatically delete the fwnode link between @con and @sup
+ * after doing that.
+ *
+ * Attempts to create duplicate links between the same pair of fwnode handles
+ * are ignored and there is no reference counting.
+ */
+int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup)
+{
+ struct fwnode_link *link;
+ int ret = 0;
+
+ mutex_lock(&fwnode_link_lock);
+
+ list_for_each_entry(link, &sup->consumers, s_hook)
+ if (link->consumer == con)
+ goto out;
+
+ link = kzalloc(sizeof(*link), GFP_KERNEL);
+ if (!link) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ link->supplier = sup;
+ INIT_LIST_HEAD(&link->s_hook);
+ link->consumer = con;
+ INIT_LIST_HEAD(&link->c_hook);
+
+ list_add(&link->s_hook, &sup->consumers);
+ list_add(&link->c_hook, &con->suppliers);
+out:
+ mutex_unlock(&fwnode_link_lock);
+
+ return ret;
+}
+
+/**
+ * fwnode_links_purge_suppliers - Delete all supplier links of fwnode_handle.
+ * @fwnode: fwnode whose supplier links need to be deleted
+ *
+ * Deletes all supplier links connecting directly to @fwnode.
+ */
+static void fwnode_links_purge_suppliers(struct fwnode_handle *fwnode)
+{
+ struct fwnode_link *link, *tmp;
+
+ mutex_lock(&fwnode_link_lock);
+ list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) {
+ list_del(&link->s_hook);
+ list_del(&link->c_hook);
+ kfree(link);
+ }
+ mutex_unlock(&fwnode_link_lock);
+}
+
+/**
+ * fwnode_links_purge_consumers - Delete all consumer links of fwnode_handle.
+ * @fwnode: fwnode whose consumer links need to be deleted
+ *
+ * Deletes all consumer links connecting directly to @fwnode.
+ */
+static void fwnode_links_purge_consumers(struct fwnode_handle *fwnode)
+{
+ struct fwnode_link *link, *tmp;
+
+ mutex_lock(&fwnode_link_lock);
+ list_for_each_entry_safe(link, tmp, &fwnode->consumers, s_hook) {
+ list_del(&link->s_hook);
+ list_del(&link->c_hook);
+ kfree(link);
+ }
+ mutex_unlock(&fwnode_link_lock);
+}
+
+/**
+ * fwnode_links_purge - Delete all links connected to a fwnode_handle.
+ * @fwnode: fwnode whose links needs to be deleted
+ *
+ * Deletes all links connecting directly to a fwnode.
+ */
+void fwnode_links_purge(struct fwnode_handle *fwnode)
+{
+ fwnode_links_purge_suppliers(fwnode);
+ fwnode_links_purge_consumers(fwnode);
+}
+
+static void fw_devlink_purge_absent_suppliers(struct fwnode_handle *fwnode)
+{
+ struct fwnode_handle *child;
+
+ /* Don't purge consumer links of an added child */
+ if (fwnode->dev)
+ return;
+
+ fwnode->flags |= FWNODE_FLAG_NOT_DEVICE;
+ fwnode_links_purge_consumers(fwnode);
+
+ fwnode_for_each_available_child_node(fwnode, child)
+ fw_devlink_purge_absent_suppliers(child);
+}
#ifdef CONFIG_SRCU
static DEFINE_MUTEX(device_links_lock);
@@ -66,14 +177,30 @@
mutex_unlock(&device_links_lock);
}
-int device_links_read_lock(void)
+int device_links_read_lock(void) __acquires(&device_links_srcu)
{
return srcu_read_lock(&device_links_srcu);
}
-void device_links_read_unlock(int idx)
+void device_links_read_unlock(int idx) __releases(&device_links_srcu)
{
srcu_read_unlock(&device_links_srcu, idx);
+}
+
+int device_links_read_lock_held(void)
+{
+ return srcu_read_lock_held(&device_links_srcu);
+}
+
+static void device_link_synchronize_removal(void)
+{
+ synchronize_srcu(&device_links_srcu);
+}
+
+static void device_link_remove_from_lists(struct device_link *link)
+{
+ list_del_rcu(&link->s_node);
+ list_del_rcu(&link->c_node);
}
#else /* !CONFIG_SRCU */
static DECLARE_RWSEM(device_links_lock);
@@ -98,10 +225,24 @@
{
up_read(&device_links_lock);
}
-#endif /* !CONFIG_SRCU */
-EXPORT_SYMBOL(device_links_read_lock);
-EXPORT_SYMBOL(device_links_read_unlock);
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+int device_links_read_lock_held(void)
+{
+ return lockdep_is_held(&device_links_lock);
+}
+#endif
+
+static inline void device_link_synchronize_removal(void)
+{
+}
+
+static void device_link_remove_from_lists(struct device_link *link)
+{
+ list_del(&link->s_node);
+ list_del(&link->c_node);
+}
+#endif /* !CONFIG_SRCU */
static bool device_is_ancestor(struct device *dev, struct device *target)
{
@@ -121,7 +262,7 @@
* 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)
+int device_is_dependent(struct device *dev, void *target)
{
struct device_link *link;
int ret;
@@ -139,7 +280,8 @@
return ret;
list_for_each_entry(link, &dev->links.consumers, s_node) {
- if (link->flags == (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED))
+ if ((link->flags & ~DL_FLAG_INFERRED) ==
+ (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED))
continue;
if (link->consumer == target)
@@ -212,7 +354,8 @@
device_for_each_child(dev, NULL, device_reorder_to_tail);
list_for_each_entry(link, &dev->links.consumers, s_node) {
- if (link->flags == (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED))
+ if ((link->flags & ~DL_FLAG_INFERRED) ==
+ (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED))
continue;
device_reorder_to_tail(link->consumer, NULL);
}
@@ -240,10 +383,230 @@
device_links_read_unlock(idx);
}
+#define to_devlink(dev) container_of((dev), struct device_link, link_dev)
+
+static ssize_t status_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ const char *output;
+
+ switch (to_devlink(dev)->status) {
+ case DL_STATE_NONE:
+ output = "not tracked";
+ break;
+ case DL_STATE_DORMANT:
+ output = "dormant";
+ break;
+ case DL_STATE_AVAILABLE:
+ output = "available";
+ break;
+ case DL_STATE_CONSUMER_PROBE:
+ output = "consumer probing";
+ break;
+ case DL_STATE_ACTIVE:
+ output = "active";
+ break;
+ case DL_STATE_SUPPLIER_UNBIND:
+ output = "supplier unbinding";
+ break;
+ default:
+ output = "unknown";
+ break;
+ }
+
+ return sysfs_emit(buf, "%s\n", output);
+}
+static DEVICE_ATTR_RO(status);
+
+static ssize_t auto_remove_on_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct device_link *link = to_devlink(dev);
+ const char *output;
+
+ if (link->flags & DL_FLAG_AUTOREMOVE_SUPPLIER)
+ output = "supplier unbind";
+ else if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER)
+ output = "consumer unbind";
+ else
+ output = "never";
+
+ return sysfs_emit(buf, "%s\n", output);
+}
+static DEVICE_ATTR_RO(auto_remove_on);
+
+static ssize_t runtime_pm_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct device_link *link = to_devlink(dev);
+
+ return sysfs_emit(buf, "%d\n", !!(link->flags & DL_FLAG_PM_RUNTIME));
+}
+static DEVICE_ATTR_RO(runtime_pm);
+
+static ssize_t sync_state_only_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct device_link *link = to_devlink(dev);
+
+ return sysfs_emit(buf, "%d\n",
+ !!(link->flags & DL_FLAG_SYNC_STATE_ONLY));
+}
+static DEVICE_ATTR_RO(sync_state_only);
+
+static struct attribute *devlink_attrs[] = {
+ &dev_attr_status.attr,
+ &dev_attr_auto_remove_on.attr,
+ &dev_attr_runtime_pm.attr,
+ &dev_attr_sync_state_only.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(devlink);
+
+static void device_link_release_fn(struct work_struct *work)
+{
+ struct device_link *link = container_of(work, struct device_link, rm_work);
+
+ /* Ensure that all references to the link object have been dropped. */
+ device_link_synchronize_removal();
+
+ pm_runtime_release_supplier(link);
+ pm_request_idle(link->supplier);
+
+ put_device(link->consumer);
+ put_device(link->supplier);
+ kfree(link);
+}
+
+static void devlink_dev_release(struct device *dev)
+{
+ struct device_link *link = to_devlink(dev);
+
+ INIT_WORK(&link->rm_work, device_link_release_fn);
+ /*
+ * It may take a while to complete this work because of the SRCU
+ * synchronization in device_link_release_fn() and if the consumer or
+ * supplier devices get deleted when it runs, so put it into the "long"
+ * workqueue.
+ */
+ queue_work(system_long_wq, &link->rm_work);
+}
+
+static struct class devlink_class = {
+ .name = "devlink",
+ .owner = THIS_MODULE,
+ .dev_groups = devlink_groups,
+ .dev_release = devlink_dev_release,
+};
+
+static int devlink_add_symlinks(struct device *dev,
+ struct class_interface *class_intf)
+{
+ int ret;
+ size_t len;
+ struct device_link *link = to_devlink(dev);
+ struct device *sup = link->supplier;
+ struct device *con = link->consumer;
+ char *buf;
+
+ len = max(strlen(dev_bus_name(sup)) + strlen(dev_name(sup)),
+ strlen(dev_bus_name(con)) + strlen(dev_name(con)));
+ len += strlen(":");
+ len += strlen("supplier:") + 1;
+ buf = kzalloc(len, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ ret = sysfs_create_link(&link->link_dev.kobj, &sup->kobj, "supplier");
+ if (ret)
+ goto out;
+
+ ret = sysfs_create_link(&link->link_dev.kobj, &con->kobj, "consumer");
+ if (ret)
+ goto err_con;
+
+ snprintf(buf, len, "consumer:%s:%s", dev_bus_name(con), dev_name(con));
+ ret = sysfs_create_link(&sup->kobj, &link->link_dev.kobj, buf);
+ if (ret)
+ goto err_con_dev;
+
+ snprintf(buf, len, "supplier:%s:%s", dev_bus_name(sup), dev_name(sup));
+ ret = sysfs_create_link(&con->kobj, &link->link_dev.kobj, buf);
+ if (ret)
+ goto err_sup_dev;
+
+ goto out;
+
+err_sup_dev:
+ snprintf(buf, len, "consumer:%s:%s", dev_bus_name(con), dev_name(con));
+ sysfs_remove_link(&sup->kobj, buf);
+err_con_dev:
+ sysfs_remove_link(&link->link_dev.kobj, "consumer");
+err_con:
+ sysfs_remove_link(&link->link_dev.kobj, "supplier");
+out:
+ kfree(buf);
+ return ret;
+}
+
+static void devlink_remove_symlinks(struct device *dev,
+ struct class_interface *class_intf)
+{
+ struct device_link *link = to_devlink(dev);
+ size_t len;
+ struct device *sup = link->supplier;
+ struct device *con = link->consumer;
+ char *buf;
+
+ sysfs_remove_link(&link->link_dev.kobj, "consumer");
+ sysfs_remove_link(&link->link_dev.kobj, "supplier");
+
+ len = max(strlen(dev_bus_name(sup)) + strlen(dev_name(sup)),
+ strlen(dev_bus_name(con)) + strlen(dev_name(con)));
+ len += strlen(":");
+ len += strlen("supplier:") + 1;
+ buf = kzalloc(len, GFP_KERNEL);
+ if (!buf) {
+ WARN(1, "Unable to properly free device link symlinks!\n");
+ return;
+ }
+
+ if (device_is_registered(con)) {
+ snprintf(buf, len, "supplier:%s:%s", dev_bus_name(sup), dev_name(sup));
+ sysfs_remove_link(&con->kobj, buf);
+ }
+ snprintf(buf, len, "consumer:%s:%s", dev_bus_name(con), dev_name(con));
+ sysfs_remove_link(&sup->kobj, buf);
+ kfree(buf);
+}
+
+static struct class_interface devlink_class_intf = {
+ .class = &devlink_class,
+ .add_dev = devlink_add_symlinks,
+ .remove_dev = devlink_remove_symlinks,
+};
+
+static int __init devlink_class_init(void)
+{
+ int ret;
+
+ ret = class_register(&devlink_class);
+ if (ret)
+ return ret;
+
+ ret = class_interface_register(&devlink_class_intf);
+ if (ret)
+ class_unregister(&devlink_class);
+
+ return ret;
+}
+postcore_initcall(devlink_class_init);
+
#define DL_MANAGED_LINK_FLAGS (DL_FLAG_AUTOREMOVE_CONSUMER | \
DL_FLAG_AUTOREMOVE_SUPPLIER | \
DL_FLAG_AUTOPROBE_CONSUMER | \
- DL_FLAG_SYNC_STATE_ONLY)
+ DL_FLAG_SYNC_STATE_ONLY | \
+ DL_FLAG_INFERRED)
#define DL_ADD_VALID_FLAGS (DL_MANAGED_LINK_FLAGS | DL_FLAG_STATELESS | \
DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE)
@@ -309,10 +672,11 @@
{
struct device_link *link;
- if (!consumer || !supplier || flags & ~DL_ADD_VALID_FLAGS ||
+ if (!consumer || !supplier || consumer == supplier ||
+ flags & ~DL_ADD_VALID_FLAGS ||
(flags & DL_FLAG_STATELESS && flags & DL_MANAGED_LINK_FLAGS) ||
(flags & DL_FLAG_SYNC_STATE_ONLY &&
- flags != DL_FLAG_SYNC_STATE_ONLY) ||
+ (flags & ~DL_FLAG_INFERRED) != DL_FLAG_SYNC_STATE_ONLY) ||
(flags & DL_FLAG_AUTOPROBE_CONSUMER &&
flags & (DL_FLAG_AUTOREMOVE_CONSUMER |
DL_FLAG_AUTOREMOVE_SUPPLIER)))
@@ -346,6 +710,17 @@
}
/*
+ * SYNC_STATE_ONLY links are useless once a consumer device has probed.
+ * So, only create it if the consumer hasn't probed yet.
+ */
+ if (flags & DL_FLAG_SYNC_STATE_ONLY &&
+ consumer->links.status != DL_DEV_NO_DRIVER &&
+ consumer->links.status != DL_DEV_PROBING) {
+ link = NULL;
+ goto out;
+ }
+
+ /*
* 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.
@@ -356,6 +731,10 @@
list_for_each_entry(link, &supplier->links.consumers, s_node) {
if (link->consumer != consumer)
continue;
+
+ if (link->flags & DL_FLAG_INFERRED &&
+ !(flags & DL_FLAG_INFERRED))
+ link->flags &= ~DL_FLAG_INFERRED;
if (flags & DL_FLAG_PM_RUNTIME) {
if (!(link->flags & DL_FLAG_PM_RUNTIME)) {
@@ -412,13 +791,6 @@
refcount_set(&link->rpm_active, 1);
- if (flags & DL_FLAG_PM_RUNTIME) {
- if (flags & DL_FLAG_RPM_ACTIVE)
- refcount_inc(&link->rpm_active);
-
- pm_runtime_new_link(consumer);
- }
-
get_device(supplier);
link->supplier = supplier;
INIT_LIST_HEAD(&link->s_node);
@@ -427,6 +799,24 @@
INIT_LIST_HEAD(&link->c_node);
link->flags = flags;
kref_init(&link->kref);
+
+ link->link_dev.class = &devlink_class;
+ device_set_pm_not_required(&link->link_dev);
+ dev_set_name(&link->link_dev, "%s:%s--%s:%s",
+ dev_bus_name(supplier), dev_name(supplier),
+ dev_bus_name(consumer), dev_name(consumer));
+ if (device_register(&link->link_dev)) {
+ put_device(&link->link_dev);
+ link = NULL;
+ goto out;
+ }
+
+ if (flags & DL_FLAG_PM_RUNTIME) {
+ if (flags & DL_FLAG_RPM_ACTIVE)
+ refcount_inc(&link->rpm_active);
+
+ pm_runtime_new_link(consumer);
+ }
/* Determine the initial link state. */
if (flags & DL_FLAG_STATELESS)
@@ -462,7 +852,7 @@
*/
device_reorder_to_tail(consumer, NULL);
- 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();
@@ -475,120 +865,18 @@
}
EXPORT_SYMBOL_GPL(device_link_add);
-/**
- * device_link_wait_for_supplier - Add device to wait_for_suppliers list
- * @consumer: Consumer device
- *
- * Marks the @consumer device as waiting for suppliers to become available by
- * adding it to the wait_for_suppliers list. The consumer device will never be
- * probed until it's removed from the wait_for_suppliers list.
- *
- * The caller is responsible for adding the links to the supplier devices once
- * they are available and removing the @consumer device from the
- * wait_for_suppliers list once links to all the suppliers have been created.
- *
- * This function is NOT meant to be called from the probe function of the
- * consumer but rather from code that creates/adds the consumer device.
- */
-static void device_link_wait_for_supplier(struct device *consumer,
- bool need_for_probe)
-{
- mutex_lock(&wfs_lock);
- list_add_tail(&consumer->links.needs_suppliers, &wait_for_suppliers);
- consumer->links.need_for_probe = need_for_probe;
- mutex_unlock(&wfs_lock);
-}
-
-static void device_link_wait_for_mandatory_supplier(struct device *consumer)
-{
- device_link_wait_for_supplier(consumer, true);
-}
-
-static void device_link_wait_for_optional_supplier(struct device *consumer)
-{
- device_link_wait_for_supplier(consumer, false);
-}
-
-/**
- * device_link_add_missing_supplier_links - Add links from consumer devices to
- * supplier devices, leaving any
- * consumer with inactive suppliers on
- * the wait_for_suppliers list
- *
- * Loops through all consumers waiting on suppliers and tries to add all their
- * supplier links. If that succeeds, the consumer device is removed from
- * wait_for_suppliers list. Otherwise, they are left in the wait_for_suppliers
- * list. Devices left on the wait_for_suppliers list will not be probed.
- *
- * The fwnode add_links callback is expected to return 0 if it has found and
- * added all the supplier links for the consumer device. It should return an
- * error if it isn't able to do so.
- *
- * The caller of device_link_wait_for_supplier() is expected to call this once
- * it's aware of potential suppliers becoming available.
- */
-static void device_link_add_missing_supplier_links(void)
-{
- struct device *dev, *tmp;
-
- mutex_lock(&wfs_lock);
- list_for_each_entry_safe(dev, tmp, &wait_for_suppliers,
- links.needs_suppliers) {
- int ret = fwnode_call_int_op(dev->fwnode, add_links, dev);
- if (!ret)
- list_del_init(&dev->links.needs_suppliers);
- else if (ret != -ENODEV)
- dev->links.need_for_probe = false;
- }
- mutex_unlock(&wfs_lock);
-}
-
-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);
-}
-
-#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 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);
+ pm_runtime_drop_link(link);
- list_del_rcu(&link->s_node);
- list_del_rcu(&link->c_node);
- call_srcu(&device_links_srcu, &link->rcu_head, __device_link_free_srcu);
+ device_link_remove_from_lists(link);
+ device_unregister(&link->link_dev);
}
-#else /* !CONFIG_SRCU */
-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));
-
- if (link->flags & DL_FLAG_PM_RUNTIME)
- pm_runtime_drop_link(link->consumer);
-
- list_del(&link->s_node);
- list_del(&link->c_node);
- device_link_free(link);
-}
-#endif /* !CONFIG_SRCU */
static void device_link_put_kref(struct device_link *link)
{
@@ -610,9 +898,7 @@
void device_link_del(struct device_link *link)
{
device_links_write_lock();
- device_pm_lock();
device_link_put_kref(link);
- device_pm_unlock();
device_links_write_unlock();
}
EXPORT_SYMBOL_GPL(device_link_del);
@@ -633,7 +919,6 @@
return;
device_links_write_lock();
- device_pm_lock();
list_for_each_entry(link, &supplier->links.consumers, s_node) {
if (link->consumer == consumer) {
@@ -642,7 +927,6 @@
}
}
- device_pm_unlock();
device_links_write_unlock();
}
EXPORT_SYMBOL_GPL(device_link_remove);
@@ -689,13 +973,17 @@
* Device waiting for supplier to become available is not allowed to
* probe.
*/
- mutex_lock(&wfs_lock);
- if (!list_empty(&dev->links.needs_suppliers) &&
- dev->links.need_for_probe) {
- mutex_unlock(&wfs_lock);
+ mutex_lock(&fwnode_link_lock);
+ if (dev->fwnode && !list_empty(&dev->fwnode->suppliers) &&
+ !fw_devlink_is_permissive()) {
+ dev_dbg(dev, "probe deferral - wait for supplier %pfwP\n",
+ list_first_entry(&dev->fwnode->suppliers,
+ struct fwnode_link,
+ c_hook)->supplier);
+ mutex_unlock(&fwnode_link_lock);
return -EPROBE_DEFER;
}
- mutex_unlock(&wfs_lock);
+ mutex_unlock(&fwnode_link_lock);
device_links_write_lock();
@@ -706,6 +994,8 @@
if (link->status != DL_STATE_AVAILABLE &&
!(link->flags & DL_FLAG_SYNC_STATE_ONLY)) {
device_links_missing_supplier(dev);
+ dev_dbg(dev, "probe deferral - supplier %s not ready\n",
+ dev_name(link->supplier));
ret = -EPROBE_DEFER;
break;
}
@@ -740,6 +1030,8 @@
{
struct device_link *link;
+ if (!dev_has_sync_state(dev))
+ return;
if (dev->state_synced)
return;
@@ -757,11 +1049,11 @@
*/
dev->state_synced = true;
- if (WARN_ON(!list_empty(&dev->links.defer_hook)))
+ if (WARN_ON(!list_empty(&dev->links.defer_sync)))
return;
get_device(dev);
- list_add_tail(&dev->links.defer_hook, list);
+ list_add_tail(&dev->links.defer_sync, list);
}
/**
@@ -779,8 +1071,8 @@
{
struct device *dev, *tmp;
- list_for_each_entry_safe(dev, tmp, list, links.defer_hook) {
- list_del_init(&dev->links.defer_hook);
+ list_for_each_entry_safe(dev, tmp, list, links.defer_sync) {
+ list_del_init(&dev->links.defer_sync);
if (dev != dont_lock_dev)
device_lock(dev);
@@ -818,12 +1110,12 @@
if (defer_sync_state_count)
goto out;
- list_for_each_entry_safe(dev, tmp, &deferred_sync, links.defer_hook) {
+ list_for_each_entry_safe(dev, tmp, &deferred_sync, links.defer_sync) {
/*
* Delete from deferred_sync list before queuing it to
- * sync_list because defer_hook is used for both lists.
+ * sync_list because defer_sync is used for both lists.
*/
- list_del_init(&dev->links.defer_hook);
+ list_del_init(&dev->links.defer_sync);
__device_links_queue_sync_state(dev, &sync_list);
}
out:
@@ -841,8 +1133,8 @@
static void __device_links_supplier_defer_sync(struct device *sup)
{
- if (list_empty(&sup->links.defer_hook))
- list_add_tail(&sup->links.defer_hook, &deferred_sync);
+ if (list_empty(&sup->links.defer_sync) && dev_has_sync_state(sup))
+ list_add_tail(&sup->links.defer_sync, &deferred_sync);
}
static void device_link_drop_managed(struct device_link *link)
@@ -851,6 +1143,19 @@
WRITE_ONCE(link->status, DL_STATE_NONE);
kref_put(&link->kref, __device_link_del);
}
+
+static ssize_t waiting_for_supplier_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ bool val;
+
+ device_lock(dev);
+ val = !list_empty(&dev->fwnode->suppliers);
+ device_unlock(dev);
+ return sysfs_emit(buf, "%u\n", val);
+}
+static DEVICE_ATTR_RO(waiting_for_supplier);
/**
* device_links_driver_bound - Update device links after probing its driver.
@@ -869,13 +1174,23 @@
LIST_HEAD(sync_list);
/*
- * If a device probes successfully, it's expected to have created all
+ * If a device binds successfully, it's expected to have created all
* the device links it needs to or make new device links as it needs
- * them. So, it no longer needs to wait on any suppliers.
+ * them. So, fw_devlink no longer needs to create device links to any
+ * of the device's suppliers.
+ *
+ * Also, if a child firmware node of this bound device is not added as
+ * a device by now, assume it is never going to be added and make sure
+ * other devices don't defer probe indefinitely by waiting for such a
+ * child device.
*/
- mutex_lock(&wfs_lock);
- list_del_init(&dev->links.needs_suppliers);
- mutex_unlock(&wfs_lock);
+ if (dev->fwnode && dev->fwnode->dev == dev) {
+ struct fwnode_handle *child;
+ fwnode_links_purge_suppliers(dev->fwnode);
+ fwnode_for_each_available_child_node(dev->fwnode, child)
+ fw_devlink_purge_absent_suppliers(child);
+ }
+ device_remove_file(dev, &dev_attr_waiting_for_supplier);
device_links_write_lock();
@@ -1055,7 +1370,7 @@
WRITE_ONCE(link->status, DL_STATE_DORMANT);
}
- list_del_init(&dev->links.defer_hook);
+ list_del_init(&dev->links.defer_sync);
__device_links_no_driver(dev);
device_links_write_unlock();
@@ -1162,9 +1477,8 @@
{
struct device_link *link, *ln;
- mutex_lock(&wfs_lock);
- list_del(&dev->links.needs_suppliers);
- mutex_unlock(&wfs_lock);
+ if (dev->class == &devlink_class)
+ return;
/*
* Delete all of the remaining links from this device to any other
@@ -1186,134 +1500,393 @@
device_links_write_unlock();
}
-static void fw_devlink_link_device(struct device *dev)
+#define FW_DEVLINK_FLAGS_PERMISSIVE (DL_FLAG_INFERRED | \
+ DL_FLAG_SYNC_STATE_ONLY)
+#define FW_DEVLINK_FLAGS_ON (DL_FLAG_INFERRED | \
+ DL_FLAG_AUTOPROBE_CONSUMER)
+#define FW_DEVLINK_FLAGS_RPM (FW_DEVLINK_FLAGS_ON | \
+ DL_FLAG_PM_RUNTIME)
+
+static u32 fw_devlink_flags = FW_DEVLINK_FLAGS_ON;
+static int __init fw_devlink_setup(char *arg)
{
- int fw_ret;
+ if (!arg)
+ return -EINVAL;
- mutex_lock(&defer_fw_devlink_lock);
- if (!defer_fw_devlink_count)
- device_link_add_missing_supplier_links();
-
- /*
- * The device's fwnode not having add_links() doesn't affect if other
- * consumers can find this device as a supplier. So, this check is
- * intentionally placed after device_link_add_missing_supplier_links().
- */
- if (!fwnode_has_op(dev->fwnode, add_links))
- goto out;
-
- /*
- * If fw_devlink is being deferred, assume all devices have mandatory
- * suppliers they need to link to later. Then, when the fw_devlink is
- * resumed, all these devices will get a chance to try and link to any
- * suppliers they have.
- */
- if (!defer_fw_devlink_count) {
- fw_ret = fwnode_call_int_op(dev->fwnode, add_links, dev);
- } else {
- fw_ret = -ENODEV;
- /*
- * defer_hook is not used to add device to deferred_sync list
- * until device is bound. Since deferred fw devlink also blocks
- * probing, same list hook can be used for deferred_fw_devlink.
- */
- list_add_tail(&dev->links.defer_hook, &deferred_fw_devlink);
+ if (strcmp(arg, "off") == 0) {
+ fw_devlink_flags = 0;
+ } else if (strcmp(arg, "permissive") == 0) {
+ fw_devlink_flags = FW_DEVLINK_FLAGS_PERMISSIVE;
+ } else if (strcmp(arg, "on") == 0) {
+ fw_devlink_flags = FW_DEVLINK_FLAGS_ON;
+ } else if (strcmp(arg, "rpm") == 0) {
+ fw_devlink_flags = FW_DEVLINK_FLAGS_RPM;
}
+ return 0;
+}
+early_param("fw_devlink", fw_devlink_setup);
- if (fw_ret == -ENODEV)
- device_link_wait_for_mandatory_supplier(dev);
- else if (fw_ret)
- device_link_wait_for_optional_supplier(dev);
+static bool fw_devlink_strict = true;
+static int __init fw_devlink_strict_setup(char *arg)
+{
+ return strtobool(arg, &fw_devlink_strict);
+}
+early_param("fw_devlink.strict", fw_devlink_strict_setup);
-out:
- mutex_unlock(&defer_fw_devlink_lock);
+u32 fw_devlink_get_flags(void)
+{
+ return fw_devlink_flags;
+}
+
+static bool fw_devlink_is_permissive(void)
+{
+ return fw_devlink_flags == FW_DEVLINK_FLAGS_PERMISSIVE;
+}
+
+bool fw_devlink_is_strict(void)
+{
+ return fw_devlink_strict && !fw_devlink_is_permissive();
+}
+
+static void fw_devlink_parse_fwnode(struct fwnode_handle *fwnode)
+{
+ if (fwnode->flags & FWNODE_FLAG_LINKS_ADDED)
+ return;
+
+ fwnode_call_int_op(fwnode, add_links);
+ fwnode->flags |= FWNODE_FLAG_LINKS_ADDED;
+}
+
+static void fw_devlink_parse_fwtree(struct fwnode_handle *fwnode)
+{
+ struct fwnode_handle *child = NULL;
+
+ fw_devlink_parse_fwnode(fwnode);
+
+ while ((child = fwnode_get_next_available_child_node(fwnode, child)))
+ fw_devlink_parse_fwtree(child);
}
/**
- * fw_devlink_pause - Pause parsing of fwnode to create device links
+ * fw_devlink_relax_cycle - Convert cyclic links to SYNC_STATE_ONLY links
+ * @con: Device to check dependencies for.
+ * @sup: Device to check against.
*
- * Calling this function defers any fwnode parsing to create device links until
- * fw_devlink_resume() is called. Both these functions are ref counted and the
- * caller needs to match the calls.
+ * Check if @sup depends on @con or any device dependent on it (its child or
+ * its consumer etc). When such a cyclic dependency is found, convert all
+ * device links created solely by fw_devlink into SYNC_STATE_ONLY device links.
+ * This is the equivalent of doing fw_devlink=permissive just between the
+ * devices in the cycle. We need to do this because, at this point, fw_devlink
+ * can't tell which of these dependencies is not a real dependency.
*
- * While fw_devlink is paused:
- * - Any device that is added won't have its fwnode parsed to create device
- * links.
- * - The probe of the device will also be deferred during this period.
- * - Any devices that were already added, but waiting for suppliers won't be
- * able to link to newly added devices.
- *
- * Once fw_devlink_resume():
- * - All the fwnodes that was not parsed will be parsed.
- * - All the devices that were deferred probing will be reattempted if they
- * aren't waiting for any more suppliers.
- *
- * This pair of functions, is mainly meant to optimize the parsing of fwnodes
- * when a lot of devices that need to link to each other are added in a short
- * interval of time. For example, adding all the top level devices in a system.
- *
- * For example, if N devices are added and:
- * - All the consumers are added before their suppliers
- * - All the suppliers of the N devices are part of the N devices
- *
- * Then:
- *
- * - With the use of fw_devlink_pause() and fw_devlink_resume(), each device
- * will only need one parsing of its fwnode because it is guaranteed to find
- * all the supplier devices already registered and ready to link to. It won't
- * have to do another pass later to find one or more suppliers it couldn't
- * find in the first parse of the fwnode. So, we'll only need O(N) fwnode
- * parses.
- *
- * - Without the use of fw_devlink_pause() and fw_devlink_resume(), we would
- * end up doing O(N^2) parses of fwnodes because every device that's added is
- * guaranteed to trigger a parse of the fwnode of every device added before
- * it. This O(N^2) parse is made worse by the fact that when a fwnode of a
- * device is parsed, all it descendant devices might need to have their
- * fwnodes parsed too (even if the devices themselves aren't added).
+ * Return 1 if a cycle is found. Otherwise, return 0.
*/
-void fw_devlink_pause(void)
+int fw_devlink_relax_cycle(struct device *con, void *sup)
{
- mutex_lock(&defer_fw_devlink_lock);
- defer_fw_devlink_count++;
- mutex_unlock(&defer_fw_devlink_lock);
+ struct device_link *link;
+ int ret;
+
+ if (con == sup)
+ return 1;
+
+ ret = device_for_each_child(con, sup, fw_devlink_relax_cycle);
+ if (ret)
+ return ret;
+
+ list_for_each_entry(link, &con->links.consumers, s_node) {
+ if ((link->flags & ~DL_FLAG_INFERRED) ==
+ (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED))
+ continue;
+
+ if (!fw_devlink_relax_cycle(link->consumer, sup))
+ continue;
+
+ ret = 1;
+
+ if (!(link->flags & DL_FLAG_INFERRED))
+ continue;
+
+ pm_runtime_drop_link(link);
+ link->flags = DL_FLAG_MANAGED | FW_DEVLINK_FLAGS_PERMISSIVE;
+ dev_dbg(link->consumer, "Relaxing link with %s\n",
+ dev_name(link->supplier));
+ }
+ return ret;
}
-/** fw_devlink_resume - Resume parsing of fwnode to create device links
+/**
+ * fw_devlink_create_devlink - Create a device link from a consumer to fwnode
+ * @con - Consumer device for the device link
+ * @sup_handle - fwnode handle of supplier
*
- * This function is used in conjunction with fw_devlink_pause() and is ref
- * counted. See documentation for fw_devlink_pause() for more details.
+ * This function will try to create a device link between the consumer device
+ * @con and the supplier device represented by @sup_handle.
+ *
+ * The supplier has to be provided as a fwnode because incorrect cycles in
+ * fwnode links can sometimes cause the supplier device to never be created.
+ * This function detects such cases and returns an error if it cannot create a
+ * device link from the consumer to a missing supplier.
+ *
+ * Returns,
+ * 0 on successfully creating a device link
+ * -EINVAL if the device link cannot be created as expected
+ * -EAGAIN if the device link cannot be created right now, but it may be
+ * possible to do that in the future
*/
-void fw_devlink_resume(void)
+static int fw_devlink_create_devlink(struct device *con,
+ struct fwnode_handle *sup_handle, u32 flags)
{
- struct device *dev, *tmp;
- LIST_HEAD(probe_list);
+ struct device *sup_dev;
+ int ret = 0;
- mutex_lock(&defer_fw_devlink_lock);
- if (!defer_fw_devlink_count) {
- WARN(true, "Unmatched fw_devlink pause/resume!");
+ sup_dev = get_dev_from_fwnode(sup_handle);
+ if (sup_dev) {
+ /*
+ * If it's one of those drivers that don't actually bind to
+ * their device using driver core, then don't wait on this
+ * supplier device indefinitely.
+ */
+ if (sup_dev->links.status == DL_DEV_NO_DRIVER &&
+ sup_handle->flags & FWNODE_FLAG_INITIALIZED) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /*
+ * If this fails, it is due to cycles in device links. Just
+ * give up on this link and treat it as invalid.
+ */
+ if (!device_link_add(con, sup_dev, flags) &&
+ !(flags & DL_FLAG_SYNC_STATE_ONLY)) {
+ dev_info(con, "Fixing up cyclic dependency with %s\n",
+ dev_name(sup_dev));
+ device_links_write_lock();
+ fw_devlink_relax_cycle(con, sup_dev);
+ device_links_write_unlock();
+ device_link_add(con, sup_dev,
+ FW_DEVLINK_FLAGS_PERMISSIVE);
+ ret = -EINVAL;
+ }
+
goto out;
}
- defer_fw_devlink_count--;
- if (defer_fw_devlink_count)
- goto out;
-
- device_link_add_missing_supplier_links();
- list_splice_tail_init(&deferred_fw_devlink, &probe_list);
-out:
- mutex_unlock(&defer_fw_devlink_lock);
+ /* Supplier that's already initialized without a struct device. */
+ if (sup_handle->flags & FWNODE_FLAG_INITIALIZED)
+ return -EINVAL;
/*
- * bus_probe_device() can cause new devices to get added and they'll
- * try to grab defer_fw_devlink_lock. So, this needs to be done outside
- * the defer_fw_devlink_lock.
+ * DL_FLAG_SYNC_STATE_ONLY doesn't block probing and supports
+ * cycles. So cycle detection isn't necessary and shouldn't be
+ * done.
*/
- list_for_each_entry_safe(dev, tmp, &probe_list, links.defer_hook) {
- list_del_init(&dev->links.defer_hook);
- bus_probe_device(dev);
+ if (flags & DL_FLAG_SYNC_STATE_ONLY)
+ return -EAGAIN;
+
+ /*
+ * If we can't find the supplier device from its fwnode, it might be
+ * due to a cyclic dependency between fwnodes. Some of these cycles can
+ * be broken by applying logic. Check for these types of cycles and
+ * break them so that devices in the cycle probe properly.
+ *
+ * If the supplier's parent is dependent on the consumer, then the
+ * consumer and supplier have a cyclic dependency. Since fw_devlink
+ * can't tell which of the inferred dependencies are incorrect, don't
+ * enforce probe ordering between any of the devices in this cyclic
+ * dependency. Do this by relaxing all the fw_devlink device links in
+ * this cycle and by treating the fwnode link between the consumer and
+ * the supplier as an invalid dependency.
+ */
+ sup_dev = fwnode_get_next_parent_dev(sup_handle);
+ if (sup_dev && device_is_dependent(con, sup_dev)) {
+ dev_info(con, "Fixing up cyclic dependency with %pfwP (%s)\n",
+ sup_handle, dev_name(sup_dev));
+ device_links_write_lock();
+ fw_devlink_relax_cycle(con, sup_dev);
+ device_links_write_unlock();
+ ret = -EINVAL;
+ } else {
+ /*
+ * Can't check for cycles or no cycles. So let's try
+ * again later.
+ */
+ ret = -EAGAIN;
+ }
+
+out:
+ put_device(sup_dev);
+ return ret;
+}
+
+/**
+ * __fw_devlink_link_to_consumers - Create device links to consumers of a device
+ * @dev - Device that needs to be linked to its consumers
+ *
+ * This function looks at all the consumer fwnodes of @dev and creates device
+ * links between the consumer device and @dev (supplier).
+ *
+ * If the consumer device has not been added yet, then this function creates a
+ * SYNC_STATE_ONLY link between @dev (supplier) and the closest ancestor device
+ * of the consumer fwnode. This is necessary to make sure @dev doesn't get a
+ * sync_state() callback before the real consumer device gets to be added and
+ * then probed.
+ *
+ * Once device links are created from the real consumer to @dev (supplier), the
+ * fwnode links are deleted.
+ */
+static void __fw_devlink_link_to_consumers(struct device *dev)
+{
+ struct fwnode_handle *fwnode = dev->fwnode;
+ struct fwnode_link *link, *tmp;
+
+ list_for_each_entry_safe(link, tmp, &fwnode->consumers, s_hook) {
+ u32 dl_flags = fw_devlink_get_flags();
+ struct device *con_dev;
+ bool own_link = true;
+ int ret;
+
+ con_dev = get_dev_from_fwnode(link->consumer);
+ /*
+ * If consumer device is not available yet, make a "proxy"
+ * SYNC_STATE_ONLY link from the consumer's parent device to
+ * the supplier device. This is necessary to make sure the
+ * supplier doesn't get a sync_state() callback before the real
+ * consumer can create a device link to the supplier.
+ *
+ * This proxy link step is needed to handle the case where the
+ * consumer's parent device is added before the supplier.
+ */
+ if (!con_dev) {
+ con_dev = fwnode_get_next_parent_dev(link->consumer);
+ /*
+ * However, if the consumer's parent device is also the
+ * parent of the supplier, don't create a
+ * consumer-supplier link from the parent to its child
+ * device. Such a dependency is impossible.
+ */
+ if (con_dev &&
+ fwnode_is_ancestor_of(con_dev->fwnode, fwnode)) {
+ put_device(con_dev);
+ con_dev = NULL;
+ } else {
+ own_link = false;
+ dl_flags = FW_DEVLINK_FLAGS_PERMISSIVE;
+ }
+ }
+
+ if (!con_dev)
+ continue;
+
+ ret = fw_devlink_create_devlink(con_dev, fwnode, dl_flags);
+ put_device(con_dev);
+ if (!own_link || ret == -EAGAIN)
+ continue;
+
+ list_del(&link->s_hook);
+ list_del(&link->c_hook);
+ kfree(link);
}
}
+
+/**
+ * __fw_devlink_link_to_suppliers - Create device links to suppliers of a device
+ * @dev - The consumer device that needs to be linked to its suppliers
+ * @fwnode - Root of the fwnode tree that is used to create device links
+ *
+ * This function looks at all the supplier fwnodes of fwnode tree rooted at
+ * @fwnode and creates device links between @dev (consumer) and all the
+ * supplier devices of the entire fwnode tree at @fwnode.
+ *
+ * The function creates normal (non-SYNC_STATE_ONLY) device links between @dev
+ * and the real suppliers of @dev. Once these device links are created, the
+ * fwnode links are deleted. When such device links are successfully created,
+ * this function is called recursively on those supplier devices. This is
+ * needed to detect and break some invalid cycles in fwnode links. See
+ * fw_devlink_create_devlink() for more details.
+ *
+ * In addition, it also looks at all the suppliers of the entire fwnode tree
+ * because some of the child devices of @dev that have not been added yet
+ * (because @dev hasn't probed) might already have their suppliers added to
+ * driver core. So, this function creates SYNC_STATE_ONLY device links between
+ * @dev (consumer) and these suppliers to make sure they don't execute their
+ * sync_state() callbacks before these child devices have a chance to create
+ * their device links. The fwnode links that correspond to the child devices
+ * aren't delete because they are needed later to create the device links
+ * between the real consumer and supplier devices.
+ */
+static void __fw_devlink_link_to_suppliers(struct device *dev,
+ struct fwnode_handle *fwnode)
+{
+ bool own_link = (dev->fwnode == fwnode);
+ struct fwnode_link *link, *tmp;
+ struct fwnode_handle *child = NULL;
+ u32 dl_flags;
+
+ if (own_link)
+ dl_flags = fw_devlink_get_flags();
+ else
+ dl_flags = FW_DEVLINK_FLAGS_PERMISSIVE;
+
+ list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) {
+ int ret;
+ struct device *sup_dev;
+ struct fwnode_handle *sup = link->supplier;
+
+ ret = fw_devlink_create_devlink(dev, sup, dl_flags);
+ if (!own_link || ret == -EAGAIN)
+ continue;
+
+ list_del(&link->s_hook);
+ list_del(&link->c_hook);
+ kfree(link);
+
+ /* If no device link was created, nothing more to do. */
+ if (ret)
+ continue;
+
+ /*
+ * If a device link was successfully created to a supplier, we
+ * now need to try and link the supplier to all its suppliers.
+ *
+ * This is needed to detect and delete false dependencies in
+ * fwnode links that haven't been converted to a device link
+ * yet. See comments in fw_devlink_create_devlink() for more
+ * details on the false dependency.
+ *
+ * Without deleting these false dependencies, some devices will
+ * never probe because they'll keep waiting for their false
+ * dependency fwnode links to be converted to device links.
+ */
+ sup_dev = get_dev_from_fwnode(sup);
+ __fw_devlink_link_to_suppliers(sup_dev, sup_dev->fwnode);
+ put_device(sup_dev);
+ }
+
+ /*
+ * Make "proxy" SYNC_STATE_ONLY device links to represent the needs of
+ * all the descendants. This proxy link step is needed to handle the
+ * case where the supplier is added before the consumer's parent device
+ * (@dev).
+ */
+ while ((child = fwnode_get_next_available_child_node(fwnode, child)))
+ __fw_devlink_link_to_suppliers(dev, child);
+}
+
+static void fw_devlink_link_device(struct device *dev)
+{
+ struct fwnode_handle *fwnode = dev->fwnode;
+
+ if (!fw_devlink_flags)
+ return;
+
+ fw_devlink_parse_fwtree(fwnode);
+
+ mutex_lock(&fwnode_link_lock);
+ __fw_devlink_link_to_consumers(dev);
+ __fw_devlink_link_to_suppliers(dev, fwnode);
+ mutex_unlock(&fwnode_link_lock);
+}
+
/* Device links support end. */
int (*platform_notify)(struct device *dev) = NULL;
@@ -1356,6 +1929,26 @@
}
#endif
+static int
+device_platform_notify(struct device *dev, enum kobject_action action)
+{
+ int ret;
+
+ ret = acpi_platform_notify(dev, action);
+ if (ret)
+ return ret;
+
+ ret = software_node_notify(dev, action);
+ if (ret)
+ return ret;
+
+ if (platform_notify && action == KOBJ_ADD)
+ platform_notify(dev);
+ else if (platform_notify_remove && action == KOBJ_REMOVE)
+ platform_notify_remove(dev);
+ return 0;
+}
+
/**
* dev_driver_string - Return a device's driver name, if at all possible
* @dev: struct device to get the name of
@@ -1374,9 +1967,7 @@
* never change once they are set, so they don't need special care.
*/
drv = READ_ONCE(dev->driver);
- return drv ? drv->name :
- (dev->bus ? dev->bus->name :
- (dev->class ? dev->class->name : ""));
+ return drv ? drv->name : dev_bus_name(dev);
}
EXPORT_SYMBOL(dev_driver_string);
@@ -1422,10 +2013,12 @@
const char *buf, size_t size)
{
struct dev_ext_attribute *ea = to_ext_attr(attr);
- char *end;
- unsigned long new = simple_strtoul(buf, &end, 0);
- if (end == buf)
- return -EINVAL;
+ int ret;
+ unsigned long new;
+
+ ret = kstrtoul(buf, 0, &new);
+ if (ret)
+ return ret;
*(unsigned long *)(ea->var) = new;
/* Always return full write size even if we didn't consume all */
return size;
@@ -1437,7 +2030,7 @@
char *buf)
{
struct dev_ext_attribute *ea = to_ext_attr(attr);
- return snprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var));
+ return sysfs_emit(buf, "%lx\n", *(unsigned long *)(ea->var));
}
EXPORT_SYMBOL_GPL(device_show_ulong);
@@ -1446,9 +2039,14 @@
const char *buf, size_t size)
{
struct dev_ext_attribute *ea = to_ext_attr(attr);
- char *end;
- long new = simple_strtol(buf, &end, 0);
- if (end == buf || new > INT_MAX || new < INT_MIN)
+ int ret;
+ long new;
+
+ ret = kstrtol(buf, 0, &new);
+ if (ret)
+ return ret;
+
+ if (new > INT_MAX || new < INT_MIN)
return -EINVAL;
*(int *)(ea->var) = new;
/* Always return full write size even if we didn't consume all */
@@ -1462,7 +2060,7 @@
{
struct dev_ext_attribute *ea = to_ext_attr(attr);
- return snprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var));
+ return sysfs_emit(buf, "%d\n", *(int *)(ea->var));
}
EXPORT_SYMBOL_GPL(device_show_int);
@@ -1483,7 +2081,7 @@
{
struct dev_ext_attribute *ea = to_ext_attr(attr);
- return snprintf(buf, PAGE_SIZE, "%d\n", *(bool *)(ea->var));
+ return sysfs_emit(buf, "%d\n", *(bool *)(ea->var));
}
EXPORT_SYMBOL_GPL(device_show_bool);
@@ -1511,6 +2109,8 @@
*/
devres_release_all(dev);
+ kfree(dev->dma_range_map);
+
if (dev->release)
dev->release(dev);
else if (dev->type && dev->type->release)
@@ -1518,8 +2118,7 @@
else if (dev->class && dev->class->dev_release)
dev->class->dev_release(dev);
else
- WARN(1, KERN_ERR "Device '%s' does not have a release() "
- "function, it is broken and must be fixed.\n",
+ WARN(1, KERN_ERR "Device '%s' does not have a release() function, it is broken and must be fixed. See Documentation/core-api/kobject.rst.\n",
dev_name(dev));
kfree(p);
}
@@ -1656,7 +2255,7 @@
struct kset *kset;
struct kobj_uevent_env *env = NULL;
int i;
- size_t count = 0;
+ int len = 0;
int retval;
/* search the kset, the device belongs to */
@@ -1686,10 +2285,10 @@
/* copy keys to file */
for (i = 0; i < env->envp_idx; i++)
- count += sprintf(&buf[count], "%s\n", env->envp[i]);
+ len += sysfs_emit_at(buf, len, "%s\n", env->envp[i]);
out:
kfree(env);
- return count;
+ return len;
}
static ssize_t uevent_store(struct device *dev, struct device_attribute *attr,
@@ -1716,7 +2315,7 @@
device_lock(dev);
val = !dev->offline;
device_unlock(dev);
- return sprintf(buf, "%u\n", val);
+ return sysfs_emit(buf, "%u\n", val);
}
static ssize_t online_store(struct device *dev, struct device_attribute *attr,
@@ -1910,8 +2509,16 @@
goto err_remove_dev_groups;
}
+ if (fw_devlink_flags && !fw_devlink_is_permissive() && dev->fwnode) {
+ error = device_create_file(dev, &dev_attr_waiting_for_supplier);
+ if (error)
+ goto err_remove_dev_online;
+ }
+
return 0;
+ err_remove_dev_online:
+ device_remove_file(dev, &dev_attr_online);
err_remove_dev_groups:
device_remove_groups(dev, dev->groups);
err_remove_type_groups:
@@ -1929,6 +2536,7 @@
struct class *class = dev->class;
const struct device_type *type = dev->type;
+ device_remove_file(dev, &dev_attr_waiting_for_supplier);
device_remove_file(dev, &dev_attr_online);
device_remove_groups(dev, dev->groups);
@@ -2119,6 +2727,9 @@
kobject_init(&dev->kobj, &device_ktype);
INIT_LIST_HEAD(&dev->dma_pools);
mutex_init(&dev->mutex);
+#ifdef CONFIG_PROVE_LOCKING
+ mutex_init(&dev->lockdep_mutex);
+#endif
lockdep_set_novalidate_class(&dev->mutex);
spin_lock_init(&dev->devres_lock);
INIT_LIST_HEAD(&dev->devres_head);
@@ -2129,8 +2740,7 @@
#endif
INIT_LIST_HEAD(&dev->links.consumers);
INIT_LIST_HEAD(&dev->links.suppliers);
- INIT_LIST_HEAD(&dev->links.needs_suppliers);
- INIT_LIST_HEAD(&dev->links.defer_hook);
+ INIT_LIST_HEAD(&dev->links.defer_sync);
dev->links.status = DL_DEV_NO_DRIVER;
}
EXPORT_SYMBOL_GPL(device_initialize);
@@ -2508,6 +3118,11 @@
* NOTE: _Never_ directly free @dev after calling this function, even
* if it returned an error! Always use put_device() to give up your
* reference instead.
+ *
+ * Rule of thumb is: if device_add() succeeds, you should call
+ * device_del() when you want to get rid of it. If device_add() has
+ * *not* succeeded, use *only* put_device() to drop the reference
+ * count.
*/
int device_add(struct device *dev)
{
@@ -2570,8 +3185,9 @@
}
/* notify platform of device entry */
- if (platform_notify)
- platform_notify(dev);
+ error = device_platform_notify(dev, KOBJ_ADD);
+ if (error)
+ goto platform_error;
error = device_create_file(dev, &dev_attr_uevent);
if (error)
@@ -2637,7 +3253,7 @@
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 */
@@ -2665,6 +3281,8 @@
SymlinkError:
device_remove_file(dev, &dev_attr_uevent);
attrError:
+ device_platform_notify(dev, KOBJ_REMOVE);
+platform_error:
kobject_uevent(&dev->kobj, KOBJ_REMOVE);
glue_dir = get_glue_dir(dev);
kobject_del(&dev->kobj);
@@ -2766,6 +3384,7 @@
struct device *parent = dev->parent;
struct kobject *glue_dir = NULL;
struct class_interface *class_intf;
+ unsigned int noio_flag;
device_lock(dev);
kill_device(dev);
@@ -2777,6 +3396,7 @@
/* Notify clients of device removal. This call must come
* before dpm_sysfs_remove().
*/
+ noio_flag = memalloc_noio_save();
if (dev->bus)
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
BUS_NOTIFY_DEL_DEVICE, dev);
@@ -2799,7 +3419,7 @@
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);
@@ -2807,14 +3427,10 @@
bus_remove_device(dev);
device_pm_remove(dev);
driver_deferred_probe_del(dev);
+ device_platform_notify(dev, KOBJ_REMOVE);
device_remove_properties(dev);
device_links_purge(dev);
- /* Notify the platform of the removal, in case they
- * need to do anything...
- */
- if (platform_notify_remove)
- platform_notify_remove(dev);
if (dev->bus)
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
BUS_NOTIFY_REMOVED_DEVICE, dev);
@@ -2822,6 +3438,7 @@
glue_dir = get_glue_dir(dev);
kobject_del(&dev->kobj);
cleanup_glue_dir(dev, glue_dir);
+ memalloc_noio_restore(noio_flag);
put_device(parent);
}
EXPORT_SYMBOL_GPL(device_del);
@@ -3011,6 +3628,34 @@
}
EXPORT_SYMBOL_GPL(device_find_child);
+/**
+ * device_find_child_by_name - device iterator for locating a child device.
+ * @parent: parent struct device
+ * @name: name of the child device
+ *
+ * This is similar to the device_find_child() function above, but it
+ * returns a reference to a device that has the name @name.
+ *
+ * NOTE: you will need to drop the reference with put_device() after use.
+ */
+struct device *device_find_child_by_name(struct device *parent,
+ const char *name)
+{
+ struct klist_iter i;
+ struct device *child;
+
+ if (!parent)
+ return NULL;
+
+ klist_iter_init(&parent->p->klist_children, &i);
+ while ((child = next_device(&i)))
+ if (sysfs_streq(dev_name(child), name) && get_device(child))
+ break;
+ klist_iter_exit(&i);
+ return child;
+}
+EXPORT_SYMBOL_GPL(device_find_child_by_name);
+
int __init devices_init(void)
{
devices_kset = kset_create_and_add("devices", &device_uevent_ops, NULL);
@@ -3117,7 +3762,6 @@
return ret;
}
-EXPORT_SYMBOL_GPL(device_online);
struct root_device {
struct device dev;
@@ -3263,40 +3907,6 @@
}
/**
- * device_create_vargs - creates a device and registers it with sysfs
- * @class: pointer to the struct class that this device should be registered to
- * @parent: pointer to the parent struct device of this new device, if any
- * @devt: the dev_t for the char device to be added
- * @drvdata: the data to be added to the device for callbacks
- * @fmt: string for the device's name
- * @args: va_list for the device's name
- *
- * This function can be used by char device classes. A struct device
- * will be created in sysfs, registered to the specified class.
- *
- * A "dev" file will be created, showing the dev_t for the device, if
- * the dev_t is not 0,0.
- * If a pointer to a parent struct device is passed in, the newly created
- * struct device will be a child of that device in sysfs.
- * The pointer to the struct device will be returned from the call.
- * Any further sysfs files that might be required can be created using this
- * pointer.
- *
- * Returns &struct device pointer on success, or ERR_PTR() on error.
- *
- * Note: the struct class passed to this function must have previously
- * been created with a call to class_create().
- */
-struct device *device_create_vargs(struct class *class, struct device *parent,
- dev_t devt, void *drvdata, const char *fmt,
- va_list args)
-{
- return device_create_groups_vargs(class, parent, devt, drvdata, NULL,
- fmt, args);
-}
-EXPORT_SYMBOL_GPL(device_create_vargs);
-
-/**
* device_create - creates a device and registers it with sysfs
* @class: pointer to the struct class that this device should be registered to
* @parent: pointer to the parent struct device of this new device, if any
@@ -3327,7 +3937,8 @@
struct device *dev;
va_start(vargs, fmt);
- dev = device_create_vargs(class, parent, devt, drvdata, fmt, vargs);
+ dev = device_create_groups_vargs(class, parent, devt, drvdata, NULL,
+ fmt, vargs);
va_end(vargs);
return dev;
}
@@ -3377,13 +3988,6 @@
}
EXPORT_SYMBOL_GPL(device_create_with_groups);
-static int __match_devt(struct device *dev, const void *data)
-{
- const dev_t *devt = data;
-
- return dev->devt == *devt;
-}
-
/**
* device_destroy - removes a device that was created with device_create()
* @class: pointer to the struct class that this device was registered with
@@ -3396,7 +4000,7 @@
{
struct device *dev;
- dev = class_find_device(class, NULL, &devt, __match_devt);
+ dev = class_find_device_by_devt(class, devt);
if (dev) {
put_device(dev);
device_unregister(dev);
@@ -3585,6 +4189,126 @@
}
EXPORT_SYMBOL_GPL(device_move);
+static int device_attrs_change_owner(struct device *dev, kuid_t kuid,
+ kgid_t kgid)
+{
+ struct kobject *kobj = &dev->kobj;
+ struct class *class = dev->class;
+ const struct device_type *type = dev->type;
+ int error;
+
+ if (class) {
+ /*
+ * Change the device groups of the device class for @dev to
+ * @kuid/@kgid.
+ */
+ error = sysfs_groups_change_owner(kobj, class->dev_groups, kuid,
+ kgid);
+ if (error)
+ return error;
+ }
+
+ if (type) {
+ /*
+ * Change the device groups of the device type for @dev to
+ * @kuid/@kgid.
+ */
+ error = sysfs_groups_change_owner(kobj, type->groups, kuid,
+ kgid);
+ if (error)
+ return error;
+ }
+
+ /* Change the device groups of @dev to @kuid/@kgid. */
+ error = sysfs_groups_change_owner(kobj, dev->groups, kuid, kgid);
+ if (error)
+ return error;
+
+ if (device_supports_offline(dev) && !dev->offline_disabled) {
+ /* Change online device attributes of @dev to @kuid/@kgid. */
+ error = sysfs_file_change_owner(kobj, dev_attr_online.attr.name,
+ kuid, kgid);
+ if (error)
+ return error;
+ }
+
+ return 0;
+}
+
+/**
+ * device_change_owner - change the owner of an existing device.
+ * @dev: device.
+ * @kuid: new owner's kuid
+ * @kgid: new owner's kgid
+ *
+ * This changes the owner of @dev and its corresponding sysfs entries to
+ * @kuid/@kgid. This function closely mirrors how @dev was added via driver
+ * core.
+ *
+ * Returns 0 on success or error code on failure.
+ */
+int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid)
+{
+ int error;
+ struct kobject *kobj = &dev->kobj;
+
+ dev = get_device(dev);
+ if (!dev)
+ return -EINVAL;
+
+ /*
+ * Change the kobject and the default attributes and groups of the
+ * ktype associated with it to @kuid/@kgid.
+ */
+ error = sysfs_change_owner(kobj, kuid, kgid);
+ if (error)
+ goto out;
+
+ /*
+ * Change the uevent file for @dev to the new owner. The uevent file
+ * was created in a separate step when @dev got added and we mirror
+ * that step here.
+ */
+ error = sysfs_file_change_owner(kobj, dev_attr_uevent.attr.name, kuid,
+ kgid);
+ if (error)
+ goto out;
+
+ /*
+ * Change the device groups, the device groups associated with the
+ * device class, and the groups associated with the device type of @dev
+ * to @kuid/@kgid.
+ */
+ error = device_attrs_change_owner(dev, kuid, kgid);
+ if (error)
+ goto out;
+
+ error = dpm_sysfs_change_owner(dev, kuid, kgid);
+ if (error)
+ goto out;
+
+#ifdef CONFIG_BLOCK
+ if (sysfs_deprecated && dev->class == &block_class)
+ goto out;
+#endif
+
+ /*
+ * Change the owner of the symlink located in the class directory of
+ * the device class associated with @dev which points to the actual
+ * directory entry for @dev to @kuid/@kgid. This ensures that the
+ * symlink shows the same permissions as its target.
+ */
+ error = sysfs_link_change_owner(&dev->class->p->subsys.kobj, &dev->kobj,
+ dev_name(dev), kuid, kgid);
+ if (error)
+ goto out;
+
+out:
+ put_device(dev);
+ return error;
+}
+EXPORT_SYMBOL_GPL(device_change_owner);
+
/**
* device_shutdown - call ->shutdown() on each device to shutdown.
*/
@@ -3662,22 +4386,21 @@
*/
#ifdef CONFIG_PRINTK
-static int
-create_syslog_header(const struct device *dev, char *hdr, size_t hdrlen)
+static void
+set_dev_info(const struct device *dev, struct dev_printk_info *dev_info)
{
const char *subsys;
- size_t pos = 0;
+
+ memset(dev_info, 0, sizeof(*dev_info));
if (dev->class)
subsys = dev->class->name;
else if (dev->bus)
subsys = dev->bus->name;
else
- return 0;
+ return;
- pos += snprintf(hdr + pos, hdrlen - pos, "SUBSYSTEM=%s", subsys);
- if (pos >= hdrlen)
- goto overflow;
+ strscpy(dev_info->subsystem, subsys, sizeof(dev_info->subsystem));
/*
* Add device identifier DEVICE=:
@@ -3693,41 +4416,28 @@
c = 'b';
else
c = 'c';
- pos++;
- pos += snprintf(hdr + pos, hdrlen - pos,
- "DEVICE=%c%u:%u",
- c, MAJOR(dev->devt), MINOR(dev->devt));
+
+ snprintf(dev_info->device, sizeof(dev_info->device),
+ "%c%u:%u", c, MAJOR(dev->devt), MINOR(dev->devt));
} else if (strcmp(subsys, "net") == 0) {
struct net_device *net = to_net_dev(dev);
- pos++;
- pos += snprintf(hdr + pos, hdrlen - pos,
- "DEVICE=n%u", net->ifindex);
+ snprintf(dev_info->device, sizeof(dev_info->device),
+ "n%u", net->ifindex);
} else {
- pos++;
- pos += snprintf(hdr + pos, hdrlen - pos,
- "DEVICE=+%s:%s", subsys, dev_name(dev));
+ snprintf(dev_info->device, sizeof(dev_info->device),
+ "+%s:%s", subsys, dev_name(dev));
}
-
- if (pos >= hdrlen)
- goto overflow;
-
- return pos;
-
-overflow:
- dev_WARN(dev, "device/subsystem name too long");
- return 0;
}
int dev_vprintk_emit(int level, const struct device *dev,
const char *fmt, va_list args)
{
- char hdr[128];
- size_t hdrlen;
+ struct dev_printk_info dev_info;
- hdrlen = create_syslog_header(dev, hdr, sizeof(hdr));
+ set_dev_info(dev, &dev_info);
- return vprintk_emit(0, level, hdrlen ? hdr : NULL, hdrlen, fmt, args);
+ return vprintk_emit(0, level, &dev_info, fmt, args);
}
EXPORT_SYMBOL(dev_vprintk_emit);
@@ -3800,6 +4510,55 @@
#endif
+/**
+ * dev_err_probe - probe error check and log helper
+ * @dev: the pointer to the struct device
+ * @err: error value to test
+ * @fmt: printf-style format string
+ * @...: arguments as specified in the format string
+ *
+ * This helper implements common pattern present in probe functions for error
+ * checking: print debug or error message depending if the error value is
+ * -EPROBE_DEFER and propagate error upwards.
+ * In case of -EPROBE_DEFER it sets also defer probe reason, which can be
+ * checked later by reading devices_deferred debugfs attribute.
+ * It replaces code sequence::
+ *
+ * if (err != -EPROBE_DEFER)
+ * dev_err(dev, ...);
+ * else
+ * dev_dbg(dev, ...);
+ * return err;
+ *
+ * with::
+ *
+ * return dev_err_probe(dev, err, ...);
+ *
+ * Returns @err.
+ *
+ */
+int dev_err_probe(const struct device *dev, int err, const char *fmt, ...)
+{
+ struct va_format vaf;
+ va_list args;
+
+ va_start(args, fmt);
+ vaf.fmt = fmt;
+ vaf.va = &args;
+
+ if (err != -EPROBE_DEFER) {
+ dev_err(dev, "error %pe: %pV", ERR_PTR(err), &vaf);
+ } else {
+ device_set_deferred_probe_reason(dev, &vaf);
+ dev_dbg(dev, "error %pe: %pV", ERR_PTR(err), &vaf);
+ }
+
+ va_end(args);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(dev_err_probe);
+
static inline bool fwnode_is_primary(struct fwnode_handle *fwnode)
{
return fwnode && !IS_ERR(fwnode->secondary);
@@ -3858,6 +4617,7 @@
else
dev->fwnode = fwnode;
}
+EXPORT_SYMBOL_GPL(set_secondary_fwnode);
/**
* device_set_of_node_from_dev - reuse device-tree node of another device
@@ -3874,3 +4634,39 @@
dev->of_node_reused = true;
}
EXPORT_SYMBOL_GPL(device_set_of_node_from_dev);
+
+int device_match_name(struct device *dev, const void *name)
+{
+ return sysfs_streq(dev_name(dev), name);
+}
+EXPORT_SYMBOL_GPL(device_match_name);
+
+int device_match_of_node(struct device *dev, const void *np)
+{
+ return dev->of_node == np;
+}
+EXPORT_SYMBOL_GPL(device_match_of_node);
+
+int device_match_fwnode(struct device *dev, const void *fwnode)
+{
+ return dev_fwnode(dev) == fwnode;
+}
+EXPORT_SYMBOL_GPL(device_match_fwnode);
+
+int device_match_devt(struct device *dev, const void *pdevt)
+{
+ return dev->devt == *(dev_t *)pdevt;
+}
+EXPORT_SYMBOL_GPL(device_match_devt);
+
+int device_match_acpi_dev(struct device *dev, const void *adev)
+{
+ return ACPI_COMPANION(dev) == adev;
+}
+EXPORT_SYMBOL(device_match_acpi_dev);
+
+int device_match_any(struct device *dev, const void *unused)
+{
+ return 1;
+}
+EXPORT_SYMBOL_GPL(device_match_any);
--
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