diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-pci-devices-pvpanic | 12 | ||||
| -rw-r--r-- | drivers/misc/pvpanic.c | 30 |
2 files changed, 41 insertions, 1 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-pci-devices-pvpanic b/Documentation/ABI/testing/sysfs-bus-pci-devices-pvpanic index 79b7dc31cd55..1936f7324155 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci-devices-pvpanic +++ b/Documentation/ABI/testing/sysfs-bus-pci-devices-pvpanic @@ -10,3 +10,15 @@ Description: Detailed bit definition refers to section <Bit Definition> from pvpanic device specification: https://git.qemu.org/?p=qemu.git;a=blob_plain;f=docs/specs/pvpanic.txt + +What: /sys/devices/pci0000:00/*/QEMU0001:00/events +Date: Jan 2021 +Contact: zhenwei pi <pizhenwei@bytedance.com> +Description: + RW attribute. Set/get which features in-use. This attribute + is used to enable/disable feature(s) of pvpanic device. + Notice that this value should be a subset of capability. + + Format: %x. + + Also refer to pvpanic device specification. diff --git a/drivers/misc/pvpanic.c b/drivers/misc/pvpanic.c index 80cdfa8f951a..b1e4922a7fda 100644 --- a/drivers/misc/pvpanic.c +++ b/drivers/misc/pvpanic.c @@ -20,6 +20,7 @@ static void __iomem *base; static unsigned int capability = PVPANIC_PANICKED | PVPANIC_CRASH_LOADED; +static unsigned int events; static ssize_t capability_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -28,8 +29,34 @@ static ssize_t capability_show(struct device *dev, } static DEVICE_ATTR_RO(capability); +static ssize_t events_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%x", events); +} + +static ssize_t events_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + unsigned int tmp; + int err; + + err = kstrtouint(buf, 16, &tmp); + if (err) + return err; + + if ((tmp & capability) != tmp) + return -EINVAL; + + events = tmp; + + return count; + +} +static DEVICE_ATTR_RW(events); + static struct attribute *pvpanic_dev_attrs[] = { &dev_attr_capability.attr, + &dev_attr_events.attr, NULL }; ATTRIBUTE_GROUPS(pvpanic_dev); @@ -41,7 +68,7 @@ MODULE_LICENSE("GPL"); static void pvpanic_send_event(unsigned int event) { - if (event & capability) + if (event & capability & events) iowrite8(event, base); } @@ -90,6 +117,7 @@ static int pvpanic_mmio_probe(struct platform_device *pdev) /* initlize capability by RDPT */ capability &= ioread8(base); + events = capability; if (capability) atomic_notifier_chain_register(&panic_notifier_list, |