From: Viktor Mihajlovski Date: Thu, 18 Mar 2021 10:03:34 +0000 (+0100) Subject: udev: fix slot based network names on s390 X-Git-Tag: v249-rc1~482 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a496a238e8ee66ce25ad13a3f46549b2e2e979fc;p=thirdparty%2Fsystemd.git udev: fix slot based network names on s390 The s390 PCI driver assigns the hotplug slot name from the function_id attribute of the PCI device using a 8 char hexadecimal format to match the underlying firmware/hypervisor notation. Further, there's always a one-to-one mapping between a PCI function and a hotplug slot, as individual functions can hot plugged even for multi-function devices. As the generic matching code will always try to parse the slot name in /sys/bus/pci/slots as a positive decimal number, either a wrong value might be produced for ID_NET_NAME_SLOT if the slot name consists of decimal numbers only, or none at all if a character in the range from 'a' to 'f' is encountered. Additionally, the generic code assumes that two interfaces share a hotplug slot, if they differ only in the function part of the PCI address. E.g., for an interface with the PCI address dddd:bb:aa.f, it will match the device to the first slot with an address dddd:bb:aa. As more than one slot may have this address for the s390 PCI driver, the wrong slot may be selected. To resolve this we're adding a new naming schema version with the flag NAMING_SLOT_FUNCTION_ID, which enables the correct matching of hotplug slots if the device has an attribute named function_id. The ID_NET_NAME_SLOT property will only be produced if there's a file /sys/bus/pci/slots/ where matches the value of /sys/bus/pci/devices/.../function_id in 8 char hex notation. Fixes #19016 See also #19078 --- diff --git a/man/systemd.net-naming-scheme.xml b/man/systemd.net-naming-scheme.xml index 646dd3e5611..fe044d236ab 100644 --- a/man/systemd.net-naming-scheme.xml +++ b/man/systemd.net-naming-scheme.xml @@ -369,6 +369,16 @@ property. + + v249 + + PCI hotplug slot names for the s390 PCI driver are a hexadecimal representation + of the function_id device attribute. This attribute is now used to build the + ID_NET_NAME_SLOT. Before that, all slot names were parsed as decimal + numbers, which could either result in an incorrect value of the ID_NET_NAME_SLOT + property or none at all. + + Note that latest may be used to denote the latest scheme known (to this diff --git a/src/shared/netif-naming-scheme.c b/src/shared/netif-naming-scheme.c index df520ab89ed..82c6625e56a 100644 --- a/src/shared/netif-naming-scheme.c +++ b/src/shared/netif-naming-scheme.c @@ -13,6 +13,7 @@ static const NamingScheme naming_schemes[] = { { "v243", NAMING_V243 }, { "v245", NAMING_V245 }, { "v247", NAMING_V247 }, + { "v249", NAMING_V249 }, /* … add more schemes here, as the logic to name devices is updated … */ }; diff --git a/src/shared/netif-naming-scheme.h b/src/shared/netif-naming-scheme.h index 28cd4e41f23..f719744d568 100644 --- a/src/shared/netif-naming-scheme.h +++ b/src/shared/netif-naming-scheme.h @@ -32,6 +32,7 @@ typedef enum NamingSchemeFlags { NAMING_LABEL_NOPREFIX = 1 << 7, /* Don't prepend ID_NET_LABEL_ONBOARD with interface type prefix */ NAMING_NSPAWN_LONG_HASH = 1 << 8, /* Shorten nspawn interfaces by including 24bit hash, instead of simple truncation */ NAMING_BRIDGE_NO_SLOT = 1 << 9, /* Don't use PCI hotplug slot information if the corresponding device is a PCI bridge */ + NAMING_SLOT_FUNCTION_ID = 1 << 10, /* Use function_id if present to identify PCI hotplug slots */ /* And now the masks that combine the features above */ NAMING_V238 = 0, @@ -41,6 +42,7 @@ typedef enum NamingSchemeFlags { NAMING_V243 = NAMING_V241 | NAMING_NETDEVSIM | NAMING_LABEL_NOPREFIX, NAMING_V245 = NAMING_V243 | NAMING_NSPAWN_LONG_HASH, NAMING_V247 = NAMING_V245 | NAMING_BRIDGE_NO_SLOT, + NAMING_V249 = NAMING_V247 | NAMING_SLOT_FUNCTION_ID, _NAMING_SCHEME_FLAGS_INVALID = -EINVAL, } NamingSchemeFlags; diff --git a/src/udev/udev-builtin-net_id.c b/src/udev/udev-builtin-net_id.c index 872833ebbc1..66c52e624cd 100644 --- a/src/udev/udev-builtin-net_id.c +++ b/src/udev/udev-builtin-net_id.c @@ -345,6 +345,32 @@ static int dev_pci_slot(sd_device *dev, struct netnames *names) { if (sd_device_get_sysname(hotplug_slot_dev, &sysname) < 0) continue; + /* The /function_id attribute is unique to the s390 PCI driver. + If present, we know that the slot's directory name for this device is + /sys/bus/pci/XXXXXXXX/ where XXXXXXXX is the fixed length 8 hexadecimal + character string representation of function_id. + Therefore we can short cut here and just check for the existence of + the slot directory. As this directory has to exist, we're emitting a + debug message for the unlikely case it's not found. + Note that the domain part of doesn't belong to the slot name here + because there's a 1-to-1 relationship between PCI function and its hotplug + slot. + */ + if (naming_scheme_has(NAMING_SLOT_FUNCTION_ID) && + sd_device_get_sysattr_value(hotplug_slot_dev, "function_id", &attr) >= 0) { + int function_id; + _cleanup_free_ char *str; + + if (safe_atoi(attr, &function_id) >= 0 && + asprintf(&str, "%s/%08x/", slots, function_id) >= 0 && + access(str, R_OK) == 0) { + hotplug_slot = function_id; + domain = 0; + } else + log_debug("No matching slot for function_id (%s).", attr); + break; + } + FOREACH_DIRENT_ALL(dent, dir, break) { int i; char str[PATH_MAX];