--- /dev/null
+/*
+ * Purpose: Export the firmware instance and label associated with
+ * a pci device to sysfs
+ * Copyright (C) 2010 Dell Inc.
+ * by Narendra K <Narendra_K@dell.com>,
+ * Jordan Hargrave <Jordan_Hargrave@dell.com>
+ *
+ * PCI Firmware Specification Revision 3.1 section 4.6.7 (DSM for Naming a
+ * PCI or PCI Express Device Under Operating Systems) defines an instance
+ * number and string name. This code retrieves them and exports them to sysfs.
+ * If the system firmware does not provide the ACPI _DSM (Device Specific
+ * Method), then the SMBIOS type 41 instance number and string is exported to
+ * sysfs.
+ *
+ * SMBIOS defines type 41 for onboard pci devices. This code retrieves
+ * the instance number and string from the type 41 record and exports
+ * it to sysfs.
+ *
+ * Please see http://linux.dell.com/wiki/index.php/Oss/libnetdevname for more
+ * information.
+ */
+
+#include <linux/dmi.h>
+#include <linux/sysfs.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/nls.h>
+#include <linux/acpi.h>
+#include <linux/pci-acpi.h>
+#include "pci.h"
+
+#ifdef CONFIG_DMI
+enum smbios_attr_enum {
+ SMBIOS_ATTR_NONE = 0,
+ SMBIOS_ATTR_LABEL_SHOW,
+ SMBIOS_ATTR_INSTANCE_SHOW,
+};
+
+static size_t find_smbios_instance_string(struct pci_dev *pdev, char *buf,
+ enum smbios_attr_enum attribute)
+{
+ const struct dmi_device *dmi;
+ struct dmi_dev_onboard *donboard;
+ int bus;
+ int devfn;
+
+ bus = pdev->bus->number;
+ devfn = pdev->devfn;
+
+ dmi = NULL;
+ while ((dmi = dmi_find_device(DMI_DEV_TYPE_DEV_ONBOARD,
+ NULL, dmi)) != NULL) {
+ donboard = dmi->device_data;
+ if (donboard && donboard->bus == bus &&
+ donboard->devfn == devfn) {
+ if (buf) {
+ if (attribute == SMBIOS_ATTR_INSTANCE_SHOW)
+ return scnprintf(buf, PAGE_SIZE,
+ "%d\n",
+ donboard->instance);
+ else if (attribute == SMBIOS_ATTR_LABEL_SHOW)
+ return scnprintf(buf, PAGE_SIZE,
+ "%s\n",
+ dmi->name);
+ }
+ return strlen(dmi->name);
+ }
+ }
+ return 0;
+}
+
+static umode_t smbios_instance_string_exist(struct kobject *kobj,
+ struct attribute *attr, int n)
+{
+ struct device *dev;
+ struct pci_dev *pdev;
+
+ dev = container_of(kobj, struct device, kobj);
+ pdev = to_pci_dev(dev);
+
+ return find_smbios_instance_string(pdev, NULL, SMBIOS_ATTR_NONE) ?
+ S_IRUGO : 0;
+}
+
+static ssize_t smbioslabel_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct pci_dev *pdev;
+ pdev = to_pci_dev(dev);
+
+ return find_smbios_instance_string(pdev, buf,
+ SMBIOS_ATTR_LABEL_SHOW);
+}
+
+static ssize_t smbiosinstance_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct pci_dev *pdev;
+ pdev = to_pci_dev(dev);
+
+ return find_smbios_instance_string(pdev, buf,
+ SMBIOS_ATTR_INSTANCE_SHOW);
+}
+
+static struct device_attribute smbios_attr_label = {
+ .attr = {.name = "label", .mode = 0444},
+ .show = smbioslabel_show,
+};
+
+static struct device_attribute smbios_attr_instance = {
+ .attr = {.name = "index", .mode = 0444},
+ .show = smbiosinstance_show,
+};
+
+static struct attribute *smbios_attributes[] = {
+ &smbios_attr_label.attr,
+ &smbios_attr_instance.attr,
+ NULL,
+};
+
+static struct attribute_group smbios_attr_group = {
+ .attrs = smbios_attributes,
+ .is_visible = smbios_instance_string_exist,
+};
+
+static int pci_create_smbiosname_file(struct pci_dev *pdev)
+{
+ return sysfs_create_group(&pdev->dev.kobj, &smbios_attr_group);
+}
+
+static void pci_remove_smbiosname_file(struct pci_dev *pdev)
+{
+ sysfs_remove_group(&pdev->dev.kobj, &smbios_attr_group);
+}
+#else
+static inline int pci_create_smbiosname_file(struct pci_dev *pdev)
+{
+ return -1;
+}
+
+static inline void pci_remove_smbiosname_file(struct pci_dev *pdev)
+{
+}
+#endif
+
+#ifdef CONFIG_ACPI
+enum acpi_attr_enum {
+ ACPI_ATTR_LABEL_SHOW,
+ ACPI_ATTR_INDEX_SHOW,
+};
+
+static void dsm_label_utf16s_to_utf8s(union acpi_object *obj, char *buf)
+{
+ int len;
+ len = utf16s_to_utf8s((const wchar_t *)obj->buffer.pointer,
+ obj->buffer.length,
+ UTF16_LITTLE_ENDIAN,
+ buf, PAGE_SIZE);
+ buf[len] = '\n';
+}
+
+static int dsm_get_label(struct device *dev, char *buf,
+ enum acpi_attr_enum attr)
+{
+ acpi_handle handle;
+ union acpi_object *obj, *tmp;
+ int len = -1;
+
+ handle = ACPI_HANDLE(dev);
+ if (!handle)
+ return -1;
+
+ obj = acpi_evaluate_dsm(handle, pci_acpi_dsm_uuid, 0x2,
+ DEVICE_LABEL_DSM, NULL);
+ if (!obj)
+ return -1;
+
+ tmp = obj->package.elements;
+ if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 2 &&
+ tmp[0].type == ACPI_TYPE_INTEGER &&
+ (tmp[1].type == ACPI_TYPE_STRING ||
+ tmp[1].type == ACPI_TYPE_BUFFER)) {
+ /*
+ * The second string element is optional even when
+ * this _DSM is implemented; when not implemented,
+ * this entry must return a null string.
+ */
+ if (attr == ACPI_ATTR_INDEX_SHOW) {
+ scnprintf(buf, PAGE_SIZE, "%llu\n", tmp->integer.value);
+ } else if (attr == ACPI_ATTR_LABEL_SHOW) {
+ if (tmp[1].type == ACPI_TYPE_STRING)
+ scnprintf(buf, PAGE_SIZE, "%s\n",
+ tmp[1].string.pointer);
+ else if (tmp[1].type == ACPI_TYPE_BUFFER)
+ dsm_label_utf16s_to_utf8s(tmp + 1, buf);
+ }
+ len = strlen(buf) > 0 ? strlen(buf) : -1;
+ }
+
+ ACPI_FREE(obj);
+
+ return len;
+}
+
+static bool device_has_dsm(struct device *dev)
+{
+ acpi_handle handle;
+
+ handle = ACPI_HANDLE(dev);
+ if (!handle)
+ return false;
+
+ return !!acpi_check_dsm(handle, pci_acpi_dsm_uuid, 0x2,
+ 1 << DEVICE_LABEL_DSM);
+}
+
+static umode_t acpi_index_string_exist(struct kobject *kobj,
+ struct attribute *attr, int n)
+{
+ struct device *dev;
+
+ dev = container_of(kobj, struct device, kobj);
+
+ if (device_has_dsm(dev))
+ return S_IRUGO;
+
+ return 0;
+}
+
+static ssize_t acpilabel_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return dsm_get_label(dev, buf, ACPI_ATTR_LABEL_SHOW);
+}
+
+static ssize_t acpiindex_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return dsm_get_label(dev, buf, ACPI_ATTR_INDEX_SHOW);
+}
+
+static struct device_attribute acpi_attr_label = {
+ .attr = {.name = "label", .mode = 0444},
+ .show = acpilabel_show,
+};
+
+static struct device_attribute acpi_attr_index = {
+ .attr = {.name = "acpi_index", .mode = 0444},
+ .show = acpiindex_show,
+};
+
+static struct attribute *acpi_attributes[] = {
+ &acpi_attr_label.attr,
+ &acpi_attr_index.attr,
+ NULL,
+};
+
+static struct attribute_group acpi_attr_group = {
+ .attrs = acpi_attributes,
+ .is_visible = acpi_index_string_exist,
+};
+
+static int pci_create_acpi_index_label_files(struct pci_dev *pdev)
+{
+ return sysfs_create_group(&pdev->dev.kobj, &acpi_attr_group);
+}
+
+static int pci_remove_acpi_index_label_files(struct pci_dev *pdev)
+{
+ sysfs_remove_group(&pdev->dev.kobj, &acpi_attr_group);
+ return 0;
+}
+#else
+static inline int pci_create_acpi_index_label_files(struct pci_dev *pdev)
+{
+ return -1;
+}
+
+static inline int pci_remove_acpi_index_label_files(struct pci_dev *pdev)
+{
+ return -1;
+}
+
+static inline bool device_has_dsm(struct device *dev)
+{
+ return false;
+}
+#endif
+
+void pci_create_firmware_label_files(struct pci_dev *pdev)
+{
+ if (device_has_dsm(&pdev->dev))
+ pci_create_acpi_index_label_files(pdev);
+ else
+ pci_create_smbiosname_file(pdev);
+}
+
+void pci_remove_firmware_label_files(struct pci_dev *pdev)
+{
+ if (device_has_dsm(&pdev->dev))
+ pci_remove_acpi_index_label_files(pdev);
+ else
+ pci_remove_smbiosname_file(pdev);
+}
Code Review / kvmfornfv.git / blobdiff