1 files changed, 60 insertions, 8 deletions

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 5eea14c1f7f5..af74cf02bb90 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -30,6 +30,7 @@
 #include <linux/msi.h>
 #include <linux/of.h>
 #include <linux/aperture.h>
+#include <linux/unaligned.h>
 #include "pci.h"
 
 #ifndef ARCH_PCI_DEV_GROUPS
@@ -177,6 +178,13 @@ static ssize_t resource_show(struct device *dev, struct device_attribute *attr,
 
 	for (i = 0; i < max; i++) {
 		struct resource *res =  &pci_dev->resource[i];
+		struct resource zerores = {};
+
+		/* For backwards compatibility */
+		if (i >= PCI_BRIDGE_RESOURCES && i <= PCI_BRIDGE_RESOURCE_END &&
+		    res->flags & (IORESOURCE_UNSET | IORESOURCE_DISABLED))
+			res = &zerores;
+
 		pci_resource_to_user(pci_dev, i, res, &start, &end);
 		len += sysfs_emit_at(buf, len, "0x%016llx 0x%016llx 0x%016llx\n",
 				     (unsigned long long)start,
@@ -201,8 +209,14 @@ static ssize_t max_link_width_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
+	ssize_t ret;
 
-	return sysfs_emit(buf, "%u\n", pcie_get_width_cap(pdev));
+	/* We read PCI_EXP_LNKCAP, so we need the device to be accessible. */
+	pci_config_pm_runtime_get(pdev);
+	ret = sysfs_emit(buf, "%u\n", pcie_get_width_cap(pdev));
+	pci_config_pm_runtime_put(pdev);
+
+	return ret;
 }
 static DEVICE_ATTR_RO(max_link_width);
 
@@ -214,7 +228,10 @@ static ssize_t current_link_speed_show(struct device *dev,
 	int err;
 	enum pci_bus_speed speed;
 
+	pci_config_pm_runtime_get(pci_dev);
 	err = pcie_capability_read_word(pci_dev, PCI_EXP_LNKSTA, &linkstat);
+	pci_config_pm_runtime_put(pci_dev);
+
 	if (err)
 		return -EINVAL;
 
@@ -231,7 +248,10 @@ static ssize_t current_link_width_show(struct device *dev,
 	u16 linkstat;
 	int err;
 
+	pci_config_pm_runtime_get(pci_dev);
 	err = pcie_capability_read_word(pci_dev, PCI_EXP_LNKSTA, &linkstat);
+	pci_config_pm_runtime_put(pci_dev);
+
 	if (err)
 		return -EINVAL;
 
@@ -247,7 +267,10 @@ static ssize_t secondary_bus_number_show(struct device *dev,
 	u8 sec_bus;
 	int err;
 
+	pci_config_pm_runtime_get(pci_dev);
 	err = pci_read_config_byte(pci_dev, PCI_SECONDARY_BUS, &sec_bus);
+	pci_config_pm_runtime_put(pci_dev);
+
 	if (err)
 		return -EINVAL;
 
@@ -263,7 +286,10 @@ static ssize_t subordinate_bus_number_show(struct device *dev,
 	u8 sub_bus;
 	int err;
 
+	pci_config_pm_runtime_get(pci_dev);
 	err = pci_read_config_byte(pci_dev, PCI_SUBORDINATE_BUS, &sub_bus);
+	pci_config_pm_runtime_put(pci_dev);
+
 	if (err)
 		return -EINVAL;
 
@@ -694,6 +720,22 @@ static ssize_t boot_vga_show(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR_RO(boot_vga);
 
+static ssize_t serial_number_show(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	struct pci_dev *pci_dev = to_pci_dev(dev);
+	u64 dsn;
+	u8 bytes[8];
+
+	dsn = pci_get_dsn(pci_dev);
+	if (!dsn)
+		return -EIO;
+
+	put_unaligned_be64(dsn, bytes);
+	return sysfs_emit(buf, "%8phD\n", bytes);
+}
+static DEVICE_ATTR_ADMIN_RO(serial_number);
+
 static ssize_t pci_read_config(struct file *filp, struct kobject *kobj,
 			       const struct bin_attribute *bin_attr, char *buf,
 			       loff_t off, size_t count)
@@ -1555,13 +1597,19 @@ static ssize_t __resource_resize_store(struct device *dev, int n,
 				       const char *buf, size_t count)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
-	unsigned long size, flags;
+	struct pci_bus *bus = pdev->bus;
+	struct resource *b_win, *res;
+	unsigned long size;
 	int ret, i;
 	u16 cmd;
 
 	if (kstrtoul(buf, 0, &size) < 0)
 		return -EINVAL;
 
+	b_win = pbus_select_window(bus, pci_resource_n(pdev, n));
+	if (!b_win)
+		return -EINVAL;
+
 	device_lock(dev);
 	if (dev->driver || pci_num_vf(pdev)) {
 		ret = -EBUSY;
@@ -1581,19 +1629,19 @@ static ssize_t __resource_resize_store(struct device *dev, int n,
 	pci_write_config_word(pdev, PCI_COMMAND,
 			      cmd & ~PCI_COMMAND_MEMORY);
 
-	flags = pci_resource_flags(pdev, n);
-
 	pci_remove_resource_files(pdev);
 
-	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
-		if (pci_resource_len(pdev, i) &&
-		    pci_resource_flags(pdev, i) == flags)
+	pci_dev_for_each_resource(pdev, res, i) {
+		if (i >= PCI_BRIDGE_RESOURCES)
+			break;
+
+		if (b_win == pbus_select_window(bus, res))
 			pci_release_resource(pdev, i);
 	}
 
 	ret = pci_resize_resource(pdev, n, size);
 
-	pci_assign_unassigned_bus_resources(pdev->bus);
+	pci_assign_unassigned_bus_resources(bus);
 
 	if (pci_create_resource_files(pdev))
 		pci_warn(pdev, "Failed to recreate resource files after BAR resizing\n");
@@ -1698,6 +1746,7 @@ late_initcall(pci_sysfs_init);
 
 static struct attribute *pci_dev_dev_attrs[] = {
 	&dev_attr_boot_vga.attr,
+	&dev_attr_serial_number.attr,
 	NULL,
 };
 
@@ -1710,6 +1759,9 @@ static umode_t pci_dev_attrs_are_visible(struct kobject *kobj,
 	if (a == &dev_attr_boot_vga.attr && pci_is_vga(pdev))
 		return a->mode;
 
+	if (a == &dev_attr_serial_number.attr && pci_get_dsn(pdev))
+		return a->mode;
+
 	return 0;
 }