PCI: Introduce /sys/bus/pci/devices/.../remove (77c27c7b) · Commits · 戴 / test

Documentation/ABI/testing/sysfs-bus-pci

+8 −0

Original line number	Diff line number	Diff line
		@@ -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>

+10 −0

Original line number	Diff line number	Diff line
		@@ -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
		----------------------------------------

+36 −0

Original line number	Diff line number	Diff line
		@@ -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,
		};