diff options
| -rw-r--r-- | arch/powerpc/platforms/pseries/eeh_driver.c | 91 |
1 files changed, 70 insertions, 21 deletions
diff --git a/arch/powerpc/platforms/pseries/eeh_driver.c b/arch/powerpc/platforms/pseries/eeh_driver.c index 37c2cf743133..a3fefb61097c 100644 --- a/arch/powerpc/platforms/pseries/eeh_driver.c +++ b/arch/powerpc/platforms/pseries/eeh_driver.c @@ -25,6 +25,7 @@ #include <linux/delay.h> #include <linux/interrupt.h> #include <linux/irq.h> +#include <linux/module.h> #include <linux/pci.h> #include <asm/eeh.h> #include <asm/eeh_event.h> @@ -47,6 +48,41 @@ static inline const char *eeh_pcid_name(struct pci_dev *pdev) return ""; } +/** + * eeh_pcid_get - Get the PCI device driver + * @pdev: PCI device + * + * The function is used to retrieve the PCI device driver for + * the indicated PCI device. Besides, we will increase the reference + * of the PCI device driver to prevent that being unloaded on + * the fly. Otherwise, kernel crash would be seen. + */ +static inline struct pci_driver *eeh_pcid_get(struct pci_dev *pdev) +{ + if (!pdev || !pdev->driver) + return NULL; + + if (!try_module_get(pdev->driver->driver.owner)) + return NULL; + + return pdev->driver; +} + +/** + * eeh_pcid_put - Dereference on the PCI device driver + * @pdev: PCI device + * + * The function is called to do dereference on the PCI device + * driver of the indicated PCI device. + */ +static inline void eeh_pcid_put(struct pci_dev *pdev) +{ + if (!pdev || !pdev->driver) + return; + + module_put(pdev->driver->driver.owner); +} + #if 0 static void print_device_node_tree(struct pci_dn *pdn, int dent) { @@ -128,23 +164,24 @@ static void *eeh_report_error(void *data, void *userdata) struct eeh_dev *edev = (struct eeh_dev *)data; struct pci_dev *dev = eeh_dev_to_pci_dev(edev); enum pci_ers_result rc, *res = userdata; - struct pci_driver *driver = dev->driver; + struct pci_driver *driver; /* We might not have the associated PCI device, * then we should continue for next one. */ if (!dev) return NULL; - dev->error_state = pci_channel_io_frozen; - if (!driver) - return NULL; + driver = eeh_pcid_get(dev); + if (!driver) return NULL; eeh_disable_irq(dev); if (!driver->err_handler || - !driver->err_handler->error_detected) + !driver->err_handler->error_detected) { + eeh_pcid_put(dev); return NULL; + } rc = driver->err_handler->error_detected(dev, pci_channel_io_frozen); @@ -152,6 +189,7 @@ static void *eeh_report_error(void *data, void *userdata) if (rc == PCI_ERS_RESULT_NEED_RESET) *res = rc; if (*res == PCI_ERS_RESULT_NONE) *res = rc; + eeh_pcid_put(dev); return NULL; } @@ -171,12 +209,14 @@ static void *eeh_report_mmio_enabled(void *data, void *userdata) enum pci_ers_result rc, *res = userdata; struct pci_driver *driver; - if (!dev) return NULL; + driver = eeh_pcid_get(dev); + if (!driver) return NULL; - if (!(driver = dev->driver) || - !driver->err_handler || - !driver->err_handler->mmio_enabled) + if (!driver->err_handler || + !driver->err_handler->mmio_enabled) { + eeh_pcid_put(dev); return NULL; + } rc = driver->err_handler->mmio_enabled(dev); @@ -184,6 +224,7 @@ static void *eeh_report_mmio_enabled(void *data, void *userdata) if (rc == PCI_ERS_RESULT_NEED_RESET) *res = rc; if (*res == PCI_ERS_RESULT_NONE) *res = rc; + eeh_pcid_put(dev); return NULL; } @@ -204,16 +245,19 @@ static void *eeh_report_reset(void *data, void *userdata) enum pci_ers_result rc, *res = userdata; struct pci_driver *driver; - if (!dev || !(driver = dev->driver)) - return NULL; - + if (!dev) return NULL; dev->error_state = pci_channel_io_normal; + driver = eeh_pcid_get(dev); + if (!driver) return NULL; + eeh_enable_irq(dev); if (!driver->err_handler || - !driver->err_handler->slot_reset) + !driver->err_handler->slot_reset) { + eeh_pcid_put(dev); return NULL; + } rc = driver->err_handler->slot_reset(dev); if ((*res == PCI_ERS_RESULT_NONE) || @@ -221,6 +265,7 @@ static void *eeh_report_reset(void *data, void *userdata) if (*res == PCI_ERS_RESULT_DISCONNECT && rc == PCI_ERS_RESULT_NEED_RESET) *res = rc; + eeh_pcid_put(dev); return NULL; } @@ -240,20 +285,22 @@ static void *eeh_report_resume(void *data, void *userdata) struct pci_driver *driver; if (!dev) return NULL; - dev->error_state = pci_channel_io_normal; - if (!(driver = dev->driver)) - return NULL; + driver = eeh_pcid_get(dev); + if (!driver) return NULL; eeh_enable_irq(dev); if (!driver->err_handler || - !driver->err_handler->resume) + !driver->err_handler->resume) { + eeh_pcid_put(dev); return NULL; + } driver->err_handler->resume(dev); + eeh_pcid_put(dev); return NULL; } @@ -272,20 +319,22 @@ static void *eeh_report_failure(void *data, void *userdata) struct pci_driver *driver; if (!dev) return NULL; - dev->error_state = pci_channel_io_perm_failure; - if (!(driver = dev->driver)) - return NULL; + driver = eeh_pcid_get(dev); + if (!driver) return NULL; eeh_disable_irq(dev); if (!driver->err_handler || - !driver->err_handler->error_detected) + !driver->err_handler->error_detected) { + eeh_pcid_put(dev); return NULL; + } driver->err_handler->error_detected(dev, pci_channel_io_perm_failure); + eeh_pcid_put(dev); return NULL; } |