iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

PCI: add rescan to /sys/.../pci_bus/.../

Browse Source 
After remove the device from /sys, we have to rescan all or
find out the bridge and access /sys../device/rescan there.

this patch add /sys/.../pci_bus/.../rescan. So user can rescan more easy.
that is more clean and easy to understand.

like after remove 0000:c4:00.0, you can rescan 0000:c4 directly.

-v2: According to Jesse, use function instead of exposing attr, so could hide
	#ifdef in header file.
     also add code to remove rescan file in remove path.
-v3: GregKH pointed out that we should use dev_attrs to avoid racing.
     So add pcibus_attrs and make it to be member of pcibus_attrs.
-v4: Change name to pcibus_dev_attrs according to GregKH

Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Yinghai Lu 2011-05-12 17:11:39 -07:00 committed by Jesse Barnes
parent da7822e5ad
commit b9d320fcb6
4 changed files with 37 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
Documentation/ABI/testing/sysfs-bus-pci
View File

@ -74,6 +74,15 @@ Description:
hot-remove the PCI device and any of its children.
Depends on CONFIG_HOTPLUG.
What: /sys/bus/pci/devices/.../pci_bus/.../rescan
Date: May 2011
Contact: Linux PCI developers <linux-pci@vger.kernel.org>
Description:
Writing a non-zero value to this attribute will
force a rescan of the bus and all child buses,
and re-discover devices removed earlier from this
part of the device tree. Depends on CONFIG_HOTPLUG.
What: /sys/bus/pci/devices/.../rescan
Date: January 2009
Contact: Linux PCI developers <linux-pci@vger.kernel.org>

26
drivers/pci/pci-sysfs.c
View File

@ -318,6 +318,25 @@ remove_store(struct device *dev, struct device_attribute *dummy,
count = ret;
return count;
}
static ssize_t
dev_bus_rescan_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
unsigned long val;
struct pci_bus *bus = to_pci_bus(dev);
if (strict_strtoul(buf, 0, &val) < 0)
return -EINVAL;
if (val) {
mutex_lock(&pci_remove_rescan_mutex);
pci_rescan_bus(bus);
mutex_unlock(&pci_remove_rescan_mutex);
}
return count;
}
#endif
struct device_attribute pci_dev_attrs[] = {
@ -347,6 +366,13 @@ struct device_attribute pci_dev_attrs[] = {
__ATTR_NULL,
};
struct device_attribute pcibus_dev_attrs[] = {
#ifdef CONFIG_HOTPLUG
__ATTR(rescan, (S_IWUSR|S_IWGRP), NULL, dev_bus_rescan_store),
#endif
__ATTR_NULL,
};
static ssize_t
boot_vga_show(struct device *dev, struct device_attribute *attr, char *buf)
{

1
drivers/pci/pci.h
View File

@ -156,6 +156,7 @@ static inline int pci_no_d1d2(struct pci_dev *dev)
}
extern struct device_attribute pci_dev_attrs[];
extern struct device_attribute pcibus_dev_attrs[];
extern struct device_attribute dev_attr_cpuaffinity;
extern struct device_attribute dev_attr_cpulistaffinity;
#ifdef CONFIG_HOTPLUG

1
drivers/pci/probe.c
View File

@ -95,6 +95,7 @@ static void release_pcibus_dev(struct device *dev)
static struct class pcibus_class = {
.name = "pci_bus",
.dev_release = &release_pcibus_dev,
.dev_attrs = pcibus_dev_attrs,
};
static int __init pcibus_class_init(void)