diff options
Diffstat (limited to 'arch/s390/net')
| -rw-r--r-- | arch/s390/net/Makefile | 1 | ||||
| -rw-r--r-- | arch/s390/net/pnet.c | 80 |
2 files changed, 81 insertions, 0 deletions
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"); |
