devlink: Support setting port function migratable cap

Suppor port function commands to enable / disable migratable
capability, this is used to set the port function as migratable.

Live migration is the process of transferring a live virtual machine
from one physical host to another without disrupting its normal
operation.

In order for a VM to be able to perform LM, all the VM components must
be able to perform migration. e.g.: to be migratable.
In order for VF to be migratable, VF must be bound to VFIO driver with
migration support.

When migratable capability is enable for a function of the port, the
device is making the necessary preparations for the function to be
migratable, which might include disabling features which cannot be
migrated.

Example of LM with migratable function configuration:
Set migratable of the VF's port function.

$ devlink port show pci/0000:06:00.0/2
pci/0000:06:00.0/2: type eth netdev enp6s0pf0vf1 flavour pcivf pfnum 0
vfnum 1
    function:
        hw_addr 00:00:00:00:00:00 migratable disable

$ devlink port function set pci/0000:06:00.0/2 migratable enable

$ devlink port show pci/0000:06:00.0/2
pci/0000:06:00.0/2: type eth netdev enp6s0pf0vf1 flavour pcivf pfnum 0
vfnum 1
    function:
        hw_addr 00:00:00:00:00:00 migratable enable

Bind VF to VFIO driver with migration support:
$ echo <pci_id> > /sys/bus/pci/devices/0000:08:00.0/driver/unbind
$ echo mlx5_vfio_pci > /sys/bus/pci/devices/0000:08:00.0/driver_override
$ echo <pci_id> > /sys/bus/pci/devices/0000:08:00.0/driver/bind

Attach VF to the VM.
Start the VM.
Perform LM.

Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: David Ahern <dsahern@kernel.org>

diff --git a/devlink/devlink.c b/devlink/devlink.c
index ad0ba47ee6d047900825c22da7cb6e7731fc6036..cb9b154b47b2c817ea0b824f9b861b908f9524ac 100644 (file)
--- a/devlink/devlink.c
+++ b/devlink/devlink.c
@@ -2250,6 +2250,18 @@ static int dl_argv_parse(struct dl *dl, uint64_t o_required,
                        if (roce)
                                opts->port_fn_caps.value |= DEVLINK_PORT_FN_CAP_ROCE;
                        o_found |= DL_OPT_PORT_FN_CAPS;
+               } else if (dl_argv_match(dl, "migratable") &&
+                          (o_all & DL_OPT_PORT_FN_CAPS)) {
+                       bool mig;
+
+                       dl_arg_inc(dl);
+                       err = dl_argv_bool(dl, &mig);
+                       if (err)
+                               return err;
+                       opts->port_fn_caps.selector |= DEVLINK_PORT_FN_CAP_MIGRATABLE;
+                       if (mig)
+                               opts->port_fn_caps.value |= DEVLINK_PORT_FN_CAP_MIGRATABLE;
+                       o_found |= DL_OPT_PORT_FN_CAPS;
                } else {
                        pr_err("Unknown option \"%s\"\n", dl_argv(dl));
                        return -EINVAL;
@@ -4527,7 +4539,7 @@ static void cmd_port_help(void)
        pr_err("       devlink port split DEV/PORT_INDEX count COUNT\n");
        pr_err("       devlink port unsplit DEV/PORT_INDEX\n");
        pr_err("       devlink port function set DEV/PORT_INDEX [ hw_addr ADDR ] [ state { active | inactive } ]\n");
-       pr_err("                      [ roce { enable | disable } ]\n");
+       pr_err("                      [ roce { enable | disable } ] [ migratable { enable | disable } ]\n");
        pr_err("       devlink port function rate { help | show | add | del | set }\n");
        pr_err("       devlink port param set DEV/PORT_INDEX name PARAMETER value VALUE cmode { permanent | driverinit | runtime }\n");
        pr_err("       devlink port param show [DEV/PORT_INDEX name PARAMETER]\n");
@@ -4649,6 +4661,10 @@ static void pr_out_port_function(struct dl *dl, struct nlattr **tb_port)
                        print_string(PRINT_ANY, "roce", " roce %s",
                                     port_fn_caps->value & DEVLINK_PORT_FN_CAP_ROCE ?
                                     "enable" : "disable");
+               if (port_fn_caps->selector & DEVLINK_PORT_FN_CAP_MIGRATABLE)
+                       print_string(PRINT_ANY, "migratable", " migratable %s",
+                                    port_fn_caps->value & DEVLINK_PORT_FN_CAP_MIGRATABLE ?
+                                    "enable" : "disable");
        }
 
        if (!dl->json_output)
@@ -4844,7 +4860,7 @@ static int cmd_port_param_show(struct dl *dl)
 static void cmd_port_function_help(void)
 {
        pr_err("Usage: devlink port function set DEV/PORT_INDEX [ hw_addr ADDR ] [ state STATE ]\n");
-       pr_err("                      [ roce { enable | disable } ]\n");
+       pr_err("                      [ roce { enable | disable } ] [ migratable { enable | disable } ]\n");
        pr_err("       devlink port function rate { help | show | add | del | set }\n");
 }