[linux-pm] [PATCH] Block on access to temporarily unavailable pci device

[matthew at wil.cx (Matthew Wilcox)]

On Tue, Oct 17, 2006 at 08:51:46AM -0600, Matthew Wilcox wrote:
> I'll post the patch I used to test blocking device accesses separately.

Here it is.  Not for applying.

Nacked-by: Matthew Wilcox <matthew at wil.cx>

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index a1d2e97..267bf76 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -175,6 +175,20 @@ msi_bus_store(struct device *dev, struct
 	return count;
 }
 
+static ssize_t
+block_store(struct device *dev, struct device_attribute *attr,
+	      const char *buf, size_t count)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	if (*buf == '0')
+		pci_unblock_user_cfg_access(pdev);
+	else if (*buf == '1')
+		pci_block_user_cfg_access(pdev);
+
+	return count;
+}
+
 struct device_attribute pci_dev_attrs[] = {
 	__ATTR_RO(resource),
 	__ATTR_RO(vendor),
@@ -189,6 +203,7 @@ 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),
+	__ATTR(block, 0200, NULL, block_store),
 	__ATTR_NULL,
 };