xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

PCI: pciehp: Add hotplug_lock to serialize hotplug events

Browse Source 
Today it is there is no protection around pciehp_enable_slot() and
pciehp_disable_slot() to ensure that they complete before another
hot-plug operation can be done on that particular slot.

This patch introduces the slot->hotplug_lock to ensure that any hotplug
operations (add / remove) complete before another hotplug event can begin
processing on that particular slot.

Signed-off-by: Rajat Jain <rajatxjain@gmail.com>
Signed-off-by: Rajat Jain <rajatjain@juniper.net>
Signed-off-by: Guenter Roeck <groeck@juniper.net>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Rajat Jain
2014-02-04 18:31:11 -08:00
committed by Bjorn Helgaas
parent c4f2f5e498
commit 50b52fdee0
4 changed files with 23 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
drivers/pci/hotplug/pciehp_ctrl.c
View File

@@ -293,6 +293,7 @@ static void pciehp_power_thread(struct work_struct *work)
struct power_work_info *info =
container_of(work, struct power_work_info, work);
struct slot *p_slot = info->p_slot;
int ret;
switch (info->req) {
case DISABLE_REQ:
@@ -300,7 +301,9 @@ static void pciehp_power_thread(struct work_struct *work)
"Disabling domain:bus:device=%04x:%02x:00\n",
pci_domain_nr(p_slot->ctrl->pcie->port->subordinate),
p_slot->ctrl->pcie->port->subordinate->number);
mutex_lock(&p_slot->hotplug_lock);
pciehp_disable_slot(p_slot);
mutex_unlock(&p_slot->hotplug_lock);
mutex_lock(&p_slot->lock);
p_slot->state = STATIC_STATE;
mutex_unlock(&p_slot->lock);
@@ -310,7 +313,10 @@ static void pciehp_power_thread(struct work_struct *work)
"Enabling domain:bus:device=%04x:%02x:00\n",
pci_domain_nr(p_slot->ctrl->pcie->port->subordinate),
p_slot->ctrl->pcie->port->subordinate->number);
if (pciehp_enable_slot(p_slot))
mutex_lock(&p_slot->hotplug_lock);
ret = pciehp_enable_slot(p_slot);
mutex_unlock(&p_slot->hotplug_lock);
if (ret)
pciehp_green_led_off(p_slot);
mutex_lock(&p_slot->lock);
p_slot->state = STATIC_STATE;
@@ -546,6 +552,9 @@ static void interrupt_event_handler(struct work_struct *work)
kfree(info);
}
/*
* Note: This function must be called with slot->hotplug_lock held
*/
int pciehp_enable_slot(struct slot *p_slot)
{
u8 getstatus = 0;
@@ -584,7 +593,9 @@ int pciehp_enable_slot(struct slot *p_slot)
return rc;
}
/*
* Note: This function must be called with slot->hotplug_lock held
*/
int pciehp_disable_slot(struct slot *p_slot)
{
u8 getstatus = 0;
@@ -617,7 +628,9 @@ int pciehp_sysfs_enable_slot(struct slot *p_slot)
case STATIC_STATE:
p_slot->state = POWERON_STATE;
mutex_unlock(&p_slot->lock);
mutex_lock(&p_slot->hotplug_lock);
retval = pciehp_enable_slot(p_slot);
mutex_unlock(&p_slot->hotplug_lock);
mutex_lock(&p_slot->lock);
p_slot->state = STATIC_STATE;
break;