iplink: add gso and gro max_size attributes for ipv4

This patch adds two attributes gso/gro_ipv4_max_size in iplink for the
user space support of the BIG TCP for IPv4:

  https://lore.kernel.org/netdev/de811bf3-e2d8-f727-72bc-c8a754a9d929@tessares.net/T/

Note that after this kernel patchset, "gso/gro_max_size" are used for IPv6
packets while "gso/gro_ipv4_max_size" are for IPv4 patckets. To not break
these old applications using "gso/gro_ipv4_max_size" for IPv4 GSO packets,
the new size will also be set on "gso/gro_ipv4_max_size" in kernel when
"gso/gro_max_size" changes to a value <= 65536.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David Ahern <dsahern@kernel.org>

diff --git a/ip/ipaddress.c b/ip/ipaddress.c
index c7553bcdbc5e7cb49214597ecb5747eadc3abd8d..9ba8143803422fa6fac72f1959acb56a6bba7f4b 100644 (file)
--- a/ip/ipaddress.c
+++ b/ip/ipaddress.c
@@ -1264,6 +1264,18 @@ int print_linkinfo(struct nlmsghdr *n, void *arg)
                                   "gro_max_size %u ",
                                   rta_getattr_u32(tb[IFLA_GRO_MAX_SIZE]));
 
+               if (tb[IFLA_GSO_IPV4_MAX_SIZE])
+                       print_uint(PRINT_ANY,
+                                  "gso_ipv4_max_size",
+                                  "gso_ipv4_max_size %u ",
+                                  rta_getattr_u32(tb[IFLA_GSO_IPV4_MAX_SIZE]));
+
+               if (tb[IFLA_GRO_IPV4_MAX_SIZE])
+                       print_uint(PRINT_ANY,
+                                  "gro_ipv4_max_size",
+                                  "gro_ipv4_max_size %u ",
+                                  rta_getattr_u32(tb[IFLA_GRO_IPV4_MAX_SIZE]));
+
                if (tb[IFLA_PHYS_PORT_NAME])
                        print_string(PRINT_ANY,
                                     "phys_port_name",

diff --git a/ip/iplink.c b/ip/iplink.c
index 4ec9e370b107d1c2a5d3d35d615235a5c054d367..a8da52f9f7ca5a8320008980d23961460ac480c2 100644 (file)
--- a/ip/iplink.c
+++ b/ip/iplink.c
@@ -114,8 +114,8 @@ void iplink_usage(void)
                "               [ addrgenmode { eui64 | none | stable_secret | random } ]\n"
                "               [ protodown { on | off } ]\n"
                "               [ protodown_reason PREASON { on | off } ]\n"
-               "               [ gso_max_size BYTES ] | [ gso_max_segs PACKETS ]\n"
-               "               [ gro_max_size BYTES ]\n"
+               "               [ gso_max_size BYTES ] [ gso_ipv4_max_size BYTES ] [ gso_max_segs PACKETS ]\n"
+               "               [ gro_max_size BYTES ] [ gro_ipv4_max_size BYTES ]\n"
                "\n"
                "       ip link show [ DEVICE | group GROUP ] [up] [master DEV] [vrf NAME] [type TYPE]\n"
                "               [nomaster]\n"
@@ -948,6 +948,24 @@ int iplink_parse(int argc, char **argv, struct iplink_req *req, char **type)
                                       *argv);
                        addattr32(&req->n, sizeof(*req),
                                  IFLA_GRO_MAX_SIZE, max_size);
+               } else if (strcmp(*argv, "gso_ipv4_max_size") == 0) {
+                       unsigned int max_size;
+
+                       NEXT_ARG();
+                       if (get_unsigned(&max_size, *argv, 0))
+                               invarg("Invalid \"gso_ipv4_max_size\" value\n",
+                                      *argv);
+                       addattr32(&req->n, sizeof(*req),
+                                 IFLA_GSO_IPV4_MAX_SIZE, max_size);
+               }  else if (strcmp(*argv, "gro_ipv4_max_size") == 0) {
+                       unsigned int max_size;
+
+                       NEXT_ARG();
+                       if (get_unsigned(&max_size, *argv, 0))
+                               invarg("Invalid \"gro_ipv4_max_size\" value\n",
+                                      *argv);
+                       addattr32(&req->n, sizeof(*req),
+                                 IFLA_GRO_IPV4_MAX_SIZE, max_size);
                } else if (strcmp(*argv, "parentdev") == 0) {
                        NEXT_ARG();
                        addattr_l(&req->n, sizeof(*req), IFLA_PARENT_DEV_NAME,

diff --git a/man/man8/ip-link.8.in b/man/man8/ip-link.8.in
index eeddf4932c831facbeb03b7d936910cebe216bd7..c8c656579364f7015f06b619198ad279541b86d3 100644 (file)
--- a/man/man8/ip-link.8.in
+++ b/man/man8/ip-link.8.in
@@ -38,11 +38,16 @@ ip-link \- network device configuration
 .br
 .RB "[ " gso_max_size
 .IR BYTES " ]"
+.RB "[ " gso_ipv4_max_size
+.IR BYTES " ]"
 .RB "[ " gso_max_segs
 .IR SEGMENTS " ]"
 .br
 .RB "[ " gro_max_size
 .IR BYTES " ]"
+.RB "[ " gro_ipv4_max_size
+.IR BYTES " ]"
+.br
 .RB "[ " netns " {"
 .IR PID " | " NETNSNAME " } ]"
 .br
@@ -90,10 +95,15 @@ ip-link \- network device configuration
 .br
 .RB "[ " gso_max_size
 .IR BYTES " ]"
+.RB "[ " gso_ipv4_max_size
+.IR BYTES " ]"
 .RB "[ " gso_max_segs
 .IR SEGMENTS " ]"
+.br
 .RB "[ " gro_max_size
 .IR BYTES " ]"
+.RB "[ " gro_ipv4_max_size
+.IR BYTES " ]"
 .br
 .RB "[ " name
 .IR NEWNAME " ]"
@@ -423,7 +433,14 @@ specifies the number of receive queues for new device.
 .TP
 .BI gso_max_size " BYTES "
 specifies the recommended maximum size of a Generic Segment Offload
-packet the new device should accept.
+packet the new device should accept. This is also used to enable BIG
+TCP for IPv6 on this device when the size is greater than 65536.
+
+.TP
+.BI gso_ipv4_max_size " BYTES "
+specifies the recommended maximum size of a IPv4 Generic Segment Offload
+packet the new device should accept. This is especially used to enable
+BIG TCP for IPv4 on this device by setting to a size greater than 65536.
 
 .TP
 .BI gso_max_segs " SEGMENTS "
@@ -432,8 +449,15 @@ segments the new device should accept.
 
 .TP
 .BI gro_max_size " BYTES "
-specifies the maximum size of a packet built by GRO stack
-on this device.
+specifies the maximum size of a packet built by GRO stack on this
+device. This is also used for BIG TCP to allow the size of a
+merged IPv6 GSO packet on this device greater than 65536.
+
+.TP
+.BI gro_ipv4_max_size " BYTES "
+specifies the maximum size of a IPv4 packet built by GRO stack on this
+device. This is especially used for BIG TCP to allow the size of a
+merged IPv4 GSO packet on this device greater than 65536.
 
 .TP
 .BI index " IDX "