linux-kernel - [RFC PATCH v2 08/12] PCI: Introduce /sys/bus/pci/devices/.../rescan

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 13 Feb 2009 13:19:34 -0700
From:	Alex Chiang <achiang@...com>
To:	jbarnes@...tuousgeek.org
Cc:	linux-pci@...r.kernel.org, linux-kernel@...r.kernel.org,
	Trent Piepho <xyzzy@...akeasy.org>, djwong@...ibm.com,
	Alex Chiang <achiang@...com>
Subject: [RFC PATCH v2 08/12] PCI: Introduce /sys/bus/pci/devices/.../rescan

This interface allows the user to force a rescan of the device's
parent bus and all subordinate buses, and rediscover devices removed
earlier from this part of the device tree.

Cc: Trent Piepho <xyzzy@...akeasy.org>
Cc: djwong@...ibm.com
Reviewed-by: James Cameron <qz@...com>
Signed-off-by: Alex Chiang <achiang@...com>
---

 Documentation/ABI/testing/sysfs-bus-pci |   10 ++++++++++
 drivers/pci/pci-sysfs.c                 |   20 ++++++++++++++++++++
 2 files changed, 30 insertions(+), 0 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index 8c0abc7..f59e963 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -15,6 +15,16 @@ Description:
 		hot-remove the PCI device and any of its children.
 		Depends on CONFIG_HOTPLUG.
 
+What:		/sys/bus/pci/devices/.../rescan
+Date:		January 2009
+Contact:	Linux PCI developers <linux-pci@...r.kernel.org>
+Description:
+		Writing a non-zero value to this attribute will
+		force a rescan of the device's parent 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/.../vpd
 Date:		February 2008
 Contact:	Ben Hutchings <bhutchings@...arflare.com>
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index e4d2c0d..6e5f141 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -220,6 +220,25 @@ msi_bus_store(struct device *dev, struct device_attribute *attr,
 }
 
 #ifdef CONFIG_HOTPLUG
+static ssize_t
+dev_rescan_store(struct device *dev, struct device_attribute *attr,
+	      const char *buf, size_t count)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	unsigned long val;
+
+	if (strict_strtoul(buf, 0, &val) < 0)
+		return -EINVAL;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (val)
+		pci_do_scan_bus(pdev->bus);
+
+	return count;
+}
+
 static void remove_callback(void *data)
 {
 	struct pci_dev *pdev = (struct pci_dev *)data;
@@ -268,6 +287,7 @@ struct device_attribute pci_dev_attrs[] = {
 	__ATTR(msi_bus, 0644, msi_bus_show, msi_bus_store),
 #ifdef CONFIG_HOTPLUG
 	__ATTR(remove, S_IWUSR, NULL, remove_store),
+	__ATTR(rescan, S_IWUSR, NULL, dev_rescan_store),
 #endif
 	__ATTR_NULL,
 };

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/