diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-pci | 8 | ||||
| -rw-r--r-- | Documentation/filesystems/sysfs-pci.txt | 10 | ||||
| -rw-r--r-- | drivers/pci/pci-sysfs.c | 36 |
3 files changed, 54 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index e6ad047cb3c2..daa791a9e85e 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -66,6 +66,14 @@ Description: re-discover previously removed devices. Depends on CONFIG_HOTPLUG. +What: /sys/bus/pci/devices/.../remove +Date: January 2009 +Contact: Linux PCI developers <linux-pci@vger.kernel.org> +Description: + Writing a non-zero value to this attribute will + hot-remove the PCI device and any of its children. + Depends on CONFIG_HOTPLUG. + What: /sys/bus/pci/devices/.../vpd Date: February 2008 Contact: Ben Hutchings <bhutchings@solarflare.com> diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt index 9f8740ca3f3b..26e4b8bc53ee 100644 --- a/Documentation/filesystems/sysfs-pci.txt +++ b/Documentation/filesystems/sysfs-pci.txt @@ -12,6 +12,7 @@ that support it. For example, a given bus might look like this: | |-- enable | |-- irq | |-- local_cpus + | |-- remove | |-- resource | |-- resource0 | |-- resource1 @@ -36,6 +37,7 @@ files, each with their own function. enable Whether the device is enabled (ascii, rw) irq IRQ number (ascii, ro) local_cpus nearby CPU mask (cpumask, ro) + remove remove device from kernel's list (ascii, wo) resource PCI resource host addresses (ascii, ro) resource0..N PCI resource N, if present (binary, mmap) resource0_wc..N_wc PCI WC map resource N, if prefetchable (binary, mmap) @@ -46,6 +48,7 @@ files, each with their own function. ro - read only file rw - file is readable and writable + wo - write only file mmap - file is mmapable ascii - file contains ascii text binary - file contains binary data @@ -73,6 +76,13 @@ that the device must be enabled for a rom read to return data succesfully. In the event a driver is not bound to the device, it can be enabled using the 'enable' file, documented above. +The 'remove' file is used to remove the PCI device, by writing a non-zero +integer to the file. This does not involve any kind of hot-plug functionality, +e.g. powering off the device. The device is removed from the kernel's list of +PCI devices, the sysfs directory for it is removed, and the device will be +removed from any drivers attached to it. Removal of PCI root buses is +disallowed. + Accessing legacy resources through sysfs ---------------------------------------- diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index be7468a5eb72..e16990ecc024 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -243,6 +243,39 @@ struct bus_attribute pci_bus_attrs[] = { __ATTR(rescan, (S_IWUSR|S_IWGRP), NULL, bus_rescan_store), __ATTR_NULL }; + +static void remove_callback(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + + mutex_lock(&pci_remove_rescan_mutex); + pci_remove_bus_device(pdev); + mutex_unlock(&pci_remove_rescan_mutex); +} + +static ssize_t +remove_store(struct device *dev, struct device_attribute *dummy, + const char *buf, size_t count) +{ + int ret = 0; + unsigned long val; + struct pci_dev *pdev = to_pci_dev(dev); + + if (strict_strtoul(buf, 0, &val) < 0) + return -EINVAL; + + if (pci_is_root_bus(pdev->bus)) + return -EBUSY; + + /* An attribute cannot be unregistered by one of its own methods, + * so we have to use this roundabout approach. + */ + if (val) + ret = device_schedule_callback(dev, remove_callback); + if (ret) + count = ret; + return count; +} #endif struct device_attribute pci_dev_attrs[] = { @@ -263,6 +296,9 @@ struct device_attribute pci_dev_attrs[] = { __ATTR(broken_parity_status,(S_IRUGO|S_IWUSR), broken_parity_status_show,broken_parity_status_store), __ATTR(msi_bus, 0644, msi_bus_show, msi_bus_store), +#ifdef CONFIG_HOTPLUG + __ATTR(remove, (S_IWUSR|S_IWGRP), NULL, remove_store), +#endif __ATTR_NULL, }; |