summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--arch/s390/Kconfig4
-rw-r--r--arch/s390/include/asm/pnet.h23
-rw-r--r--arch/s390/net/Makefile1
-rw-r--r--arch/s390/net/pnet.c80
4 files changed, 108 insertions, 0 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 199ac3e4da1d..4f778af8323f 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -847,6 +847,10 @@ config CCW
source "drivers/Kconfig"
+config HAVE_PNETID
+ tristate
+ default (SMC || CCWGROUP)
+
source "fs/Kconfig"
source "arch/s390/Kconfig.debug"
diff --git a/arch/s390/include/asm/pnet.h b/arch/s390/include/asm/pnet.h
new file mode 100644
index 000000000000..6e278584f8f1
--- /dev/null
+++ b/arch/s390/include/asm/pnet.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * IBM System z PNET ID Support
+ *
+ * Copyright IBM Corp. 2018
+ */
+
+#ifndef _ASM_S390_PNET_H
+#define _ASM_S390_PNET_H
+
+#include <linux/device.h>
+#include <linux/types.h>
+
+#define PNETIDS_LEN 64 /* Total utility string length in bytes
+ * to cover up to 4 PNETIDs of 16 bytes
+ * for up to 4 device ports
+ */
+#define MAX_PNETID_LEN 16 /* Max.length of a single port PNETID */
+#define MAX_PNETID_PORTS (PNETIDS_LEN / MAX_PNETID_LEN)
+ /* Max. # of ports with a PNETID */
+
+int pnet_id_by_dev_port(struct device *dev, unsigned short port, u8 *pnetid);
+#endif /* _ASM_S390_PNET_H */
diff --git a/arch/s390/net/Makefile b/arch/s390/net/Makefile
index e0d5f245e42b..e2b85ffdbb0c 100644
--- a/arch/s390/net/Makefile
+++ b/arch/s390/net/Makefile
@@ -3,3 +3,4 @@
# Arch-specific network modules
#
obj-$(CONFIG_BPF_JIT) += bpf_jit.o bpf_jit_comp.o
+obj-$(CONFIG_HAVE_PNETID) += pnet.o
diff --git a/arch/s390/net/pnet.c b/arch/s390/net/pnet.c
new file mode 100644
index 000000000000..e22f1b10a6c7
--- /dev/null
+++ b/arch/s390/net/pnet.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IBM System z PNET ID Support
+ *
+ * Copyright IBM Corp. 2018
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/types.h>
+#include <asm/ccwgroup.h>
+#include <asm/ccwdev.h>
+#include <asm/pnet.h>
+
+/*
+ * Get the PNETIDs from a device.
+ * s390 hardware supports the definition of a so-called Physical Network
+ * Identifier (short PNETID) per network device port. These PNETIDs can be
+ * used to identify network devices that are attached to the same physical
+ * network (broadcast domain).
+ *
+ * The device can be
+ * - a ccwgroup device with all bundled subchannels having the same PNETID
+ * - a PCI attached network device
+ *
+ * Returns:
+ * 0: PNETIDs extracted from device.
+ * -ENOMEM: No memory to extract utility string.
+ * -EOPNOTSUPP: Device type without utility string support
+ */
+static int pnet_ids_by_device(struct device *dev, u8 *pnetids)
+{
+ memset(pnetids, 0, PNETIDS_LEN);
+ if (dev_is_ccwgroup(dev)) {
+ struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
+ u8 *util_str;
+
+ util_str = ccw_device_get_util_str(gdev->cdev[0], 0);
+ if (!util_str)
+ return -ENOMEM;
+ memcpy(pnetids, util_str, PNETIDS_LEN);
+ kfree(util_str);
+ return 0;
+ }
+ if (dev_is_pci(dev)) {
+ struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
+
+ memcpy(pnetids, zdev->util_str, sizeof(zdev->util_str));
+ return 0;
+ }
+ return -EOPNOTSUPP;
+}
+
+/*
+ * Extract the pnetid for a device port.
+ *
+ * Return 0 if a pnetid is found and -ENOENT otherwise.
+ */
+int pnet_id_by_dev_port(struct device *dev, unsigned short port, u8 *pnetid)
+{
+ u8 pnetids[MAX_PNETID_PORTS][MAX_PNETID_LEN];
+ static const u8 zero[MAX_PNETID_LEN] = { 0 };
+ int rc = 0;
+
+ if (!dev || port >= MAX_PNETID_PORTS)
+ return -ENOENT;
+
+ if (!pnet_ids_by_device(dev, (u8 *)pnetids) &&
+ memcmp(pnetids[port], zero, MAX_PNETID_LEN))
+ memcpy(pnetid, pnetids[port], MAX_PNETID_LEN);
+ else
+ rc = -ENOENT;
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(pnet_id_by_dev_port);
+
+MODULE_DESCRIPTION("pnetid determination from utility strings");
+MODULE_LICENSE("GPL");