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authorLinus Torvalds <torvalds@linux-foundation.org>2012-04-04 14:26:40 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-04-04 14:26:40 -0700
commit64ebe987311853ea857a244439de5b947a4b1b07 (patch)
treeb33ab6efd7f118e0f6ab5a6bcbd59ba31a313da5 /drivers/base
parenta5149bf3fed59b94207809704b5d06fec337a771 (diff)
parentc4772d192c70b61d52262b0db76f7abd8aeb51c6 (diff)
Merge tag 'pm-for-3.4-part-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management updates from Rafael Wysocki: - Patch series that hopefully fixes races between the freezer and request_firmware() and request_firmware_nowait() for good, with two cleanups from Stephen Boyd on top. - Runtime PM fix from Alan Stern preventing tasks from getting stuck indefinitely in the runtime PM wait queue. - Device PM QoS update from MyungJoo Ham introducing a new variant of pm_qos_update_request() allowing the callers to specify a timeout. * tag 'pm-for-3.4-part-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM / QoS: add pm_qos_update_request_timeout() API firmware_class: Move request_firmware_nowait() to workqueues firmware_class: Reorganize fw_create_instance() PM / Sleep: Mitigate race between the freezer and request_firmware() PM / Sleep: Move disabling of usermode helpers to the freezer PM / Hibernate: Disable usermode helpers right before freezing tasks firmware_class: Do not warn that system is not ready from async loads firmware_class: Split _request_firmware() into three functions, v2 firmware_class: Rework usermodehelper check PM / Runtime: don't forget to wake up waitqueue on failure
Diffstat (limited to 'drivers/base')
-rw-r--r--drivers/base/firmware_class.c208
-rw-r--r--drivers/base/power/runtime.c3
2 files changed, 110 insertions, 101 deletions
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 6c9387d646ec..5401814c874d 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -16,10 +16,11 @@
#include <linux/interrupt.h>
#include <linux/bitops.h>
#include <linux/mutex.h>
-#include <linux/kthread.h>
+#include <linux/workqueue.h>
#include <linux/highmem.h>
#include <linux/firmware.h>
#include <linux/slab.h>
+#include <linux/sched.h>
#define to_dev(obj) container_of(obj, struct device, kobj)
@@ -81,6 +82,11 @@ enum {
static int loading_timeout = 60; /* In seconds */
+static inline long firmware_loading_timeout(void)
+{
+ return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
+}
+
/* fw_lock could be moved to 'struct firmware_priv' but since it is just
* guarding for corner cases a global lock should be OK */
static DEFINE_MUTEX(fw_lock);
@@ -440,13 +446,11 @@ fw_create_instance(struct firmware *firmware, const char *fw_name,
{
struct firmware_priv *fw_priv;
struct device *f_dev;
- int error;
fw_priv = kzalloc(sizeof(*fw_priv) + strlen(fw_name) + 1 , GFP_KERNEL);
if (!fw_priv) {
dev_err(device, "%s: kmalloc failed\n", __func__);
- error = -ENOMEM;
- goto err_out;
+ return ERR_PTR(-ENOMEM);
}
fw_priv->fw = firmware;
@@ -463,98 +467,80 @@ fw_create_instance(struct firmware *firmware, const char *fw_name,
f_dev->parent = device;
f_dev->class = &firmware_class;
- dev_set_uevent_suppress(f_dev, true);
-
- /* Need to pin this module until class device is destroyed */
- __module_get(THIS_MODULE);
-
- error = device_add(f_dev);
- if (error) {
- dev_err(device, "%s: device_register failed\n", __func__);
- goto err_put_dev;
- }
-
- error = device_create_bin_file(f_dev, &firmware_attr_data);
- if (error) {
- dev_err(device, "%s: sysfs_create_bin_file failed\n", __func__);
- goto err_del_dev;
- }
-
- error = device_create_file(f_dev, &dev_attr_loading);
- if (error) {
- dev_err(device, "%s: device_create_file failed\n", __func__);
- goto err_del_bin_attr;
- }
-
- if (uevent)
- dev_set_uevent_suppress(f_dev, false);
-
return fw_priv;
-
-err_del_bin_attr:
- device_remove_bin_file(f_dev, &firmware_attr_data);
-err_del_dev:
- device_del(f_dev);
-err_put_dev:
- put_device(f_dev);
-err_out:
- return ERR_PTR(error);
}
-static void fw_destroy_instance(struct firmware_priv *fw_priv)
-{
- struct device *f_dev = &fw_priv->dev;
-
- device_remove_file(f_dev, &dev_attr_loading);
- device_remove_bin_file(f_dev, &firmware_attr_data);
- device_unregister(f_dev);
-}
-
-static int _request_firmware(const struct firmware **firmware_p,
- const char *name, struct device *device,
- bool uevent, bool nowait)
+static struct firmware_priv *
+_request_firmware_prepare(const struct firmware **firmware_p, const char *name,
+ struct device *device, bool uevent, bool nowait)
{
- struct firmware_priv *fw_priv;
struct firmware *firmware;
- int retval = 0;
+ struct firmware_priv *fw_priv;
if (!firmware_p)
- return -EINVAL;
+ return ERR_PTR(-EINVAL);
*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
if (!firmware) {
dev_err(device, "%s: kmalloc(struct firmware) failed\n",
__func__);
- return -ENOMEM;
+ return ERR_PTR(-ENOMEM);
}
if (fw_get_builtin_firmware(firmware, name)) {
dev_dbg(device, "firmware: using built-in firmware %s\n", name);
- return 0;
+ return NULL;
+ }
+
+ fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
+ if (IS_ERR(fw_priv)) {
+ release_firmware(firmware);
+ *firmware_p = NULL;
}
+ return fw_priv;
+}
- read_lock_usermodehelper();
+static void _request_firmware_cleanup(const struct firmware **firmware_p)
+{
+ release_firmware(*firmware_p);
+ *firmware_p = NULL;
+}
- if (WARN_ON(usermodehelper_is_disabled())) {
- dev_err(device, "firmware: %s will not be loaded\n", name);
- retval = -EBUSY;
- goto out;
+static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
+ long timeout)
+{
+ int retval = 0;
+ struct device *f_dev = &fw_priv->dev;
+
+ dev_set_uevent_suppress(f_dev, true);
+
+ /* Need to pin this module until class device is destroyed */
+ __module_get(THIS_MODULE);
+
+ retval = device_add(f_dev);
+ if (retval) {
+ dev_err(f_dev, "%s: device_register failed\n", __func__);
+ goto err_put_dev;
}
- if (uevent)
- dev_dbg(device, "firmware: requesting %s\n", name);
+ retval = device_create_bin_file(f_dev, &firmware_attr_data);
+ if (retval) {
+ dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
+ goto err_del_dev;
+ }
- fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
- if (IS_ERR(fw_priv)) {
- retval = PTR_ERR(fw_priv);
- goto out;
+ retval = device_create_file(f_dev, &dev_attr_loading);
+ if (retval) {
+ dev_err(f_dev, "%s: device_create_file failed\n", __func__);
+ goto err_del_bin_attr;
}
if (uevent) {
- if (loading_timeout > 0)
+ dev_set_uevent_suppress(f_dev, false);
+ dev_dbg(f_dev, "firmware: requesting %s\n", fw_priv->fw_id);
+ if (timeout != MAX_SCHEDULE_TIMEOUT)
mod_timer(&fw_priv->timeout,
- round_jiffies_up(jiffies +
- loading_timeout * HZ));
+ round_jiffies_up(jiffies + timeout));
kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
}
@@ -570,16 +556,13 @@ static int _request_firmware(const struct firmware **firmware_p,
fw_priv->fw = NULL;
mutex_unlock(&fw_lock);
- fw_destroy_instance(fw_priv);
-
-out:
- read_unlock_usermodehelper();
-
- if (retval) {
- release_firmware(firmware);
- *firmware_p = NULL;
- }
-
+ device_remove_file(f_dev, &dev_attr_loading);
+err_del_bin_attr:
+ device_remove_bin_file(f_dev, &firmware_attr_data);
+err_del_dev:
+ device_del(f_dev);
+err_put_dev:
+ put_device(f_dev);
return retval;
}
@@ -602,7 +585,26 @@ int
request_firmware(const struct firmware **firmware_p, const char *name,
struct device *device)
{
- return _request_firmware(firmware_p, name, device, true, false);
+ struct firmware_priv *fw_priv;
+ int ret;
+
+ fw_priv = _request_firmware_prepare(firmware_p, name, device, true,
+ false);
+ if (IS_ERR_OR_NULL(fw_priv))
+ return PTR_RET(fw_priv);
+
+ ret = usermodehelper_read_trylock();
+ if (WARN_ON(ret)) {
+ dev_err(device, "firmware: %s will not be loaded\n", name);
+ } else {
+ ret = _request_firmware_load(fw_priv, true,
+ firmware_loading_timeout());
+ usermodehelper_read_unlock();
+ }
+ if (ret)
+ _request_firmware_cleanup(firmware_p);
+
+ return ret;
}
/**
@@ -629,25 +631,39 @@ struct firmware_work {
bool uevent;
};
-static int request_firmware_work_func(void *arg)
+static void request_firmware_work_func(struct work_struct *work)
{
- struct firmware_work *fw_work = arg;
+ struct firmware_work *fw_work;
const struct firmware *fw;
+ struct firmware_priv *fw_priv;
+ long timeout;
int ret;
- if (!arg) {
- WARN_ON(1);
- return 0;
+ fw_work = container_of(work, struct firmware_work, work);
+ fw_priv = _request_firmware_prepare(&fw, fw_work->name, fw_work->device,
+ fw_work->uevent, true);
+ if (IS_ERR_OR_NULL(fw_priv)) {
+ ret = PTR_RET(fw_priv);
+ goto out;
+ }
+
+ timeout = usermodehelper_read_lock_wait(firmware_loading_timeout());
+ if (timeout) {
+ ret = _request_firmware_load(fw_priv, fw_work->uevent, timeout);
+ usermodehelper_read_unlock();
+ } else {
+ dev_dbg(fw_work->device, "firmware: %s loading timed out\n",
+ fw_work->name);
+ ret = -EAGAIN;
}
+ if (ret)
+ _request_firmware_cleanup(&fw);
- ret = _request_firmware(&fw, fw_work->name, fw_work->device,
- fw_work->uevent, true);
+ out:
fw_work->cont(fw, fw_work->context);
module_put(fw_work->module);
kfree(fw_work);
-
- return ret;
}
/**
@@ -673,7 +689,6 @@ request_firmware_nowait(
const char *name, struct device *device, gfp_t gfp, void *context,
void (*cont)(const struct firmware *fw, void *context))
{
- struct task_struct *task;
struct firmware_work *fw_work;
fw_work = kzalloc(sizeof (struct firmware_work), gfp);
@@ -692,15 +707,8 @@ request_firmware_nowait(
return -EFAULT;
}
- task = kthread_run(request_firmware_work_func, fw_work,
- "firmware/%s", name);
- if (IS_ERR(task)) {
- fw_work->cont(NULL, fw_work->context);
- module_put(fw_work->module);
- kfree(fw_work);
- return PTR_ERR(task);
- }
-
+ INIT_WORK(&fw_work->work, request_firmware_work_func);
+ schedule_work(&fw_work->work);
return 0;
}
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index 541f821d4ea6..bd0f3949bcf9 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -532,6 +532,8 @@ static int rpm_suspend(struct device *dev, int rpmflags)
dev->power.suspend_time = ktime_set(0, 0);
dev->power.max_time_suspended_ns = -1;
dev->power.deferred_resume = false;
+ wake_up_all(&dev->power.wait_queue);
+
if (retval == -EAGAIN || retval == -EBUSY) {
dev->power.runtime_error = 0;
@@ -547,7 +549,6 @@ static int rpm_suspend(struct device *dev, int rpmflags)
} else {
pm_runtime_cancel_pending(dev);
}
- wake_up_all(&dev->power.wait_queue);
goto out;
}