Merge tag 'mlx5-updates-2019-06-13' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux

Saeed Mahameed says:

====================
mlx5-updates-2019-06-13

Mlx5 devlink health fw reporters and sw reset support

This series provides mlx5 firmware reset support and firmware devlink health
reporters.

1) Add initial mlx5 kernel documentation and include devlink health reporters

2) Add CR-Space access and FW Crdump snapshot support via devlink region_snapshot

3) Issue software reset upon FW asserts

4) Add fw and fw_fatal devlink heath reporters to follow fw errors indication by
dump and recover procedures and enable trigger these functionality by user.

4.1) fw reporter:
The fw reporter implements diagnose and dump callbacks.
It follows symptoms of fw error such as fw syndrome by triggering
fw core dump and storing it and any other fw trace into the dump buffer.
The fw reporter diagnose command can be triggered any time by the user to check
current fw status.

4.2) fw_fatal repoter:
The fw_fatal reporter implements dump and recover callbacks.
It follows fatal errors indications by CR-space dump and recover flow.
The CR-space dump uses vsc interface which is valid even if the FW command
interface is not functional, which is the case in most FW fatal errors. The
CR-space dump is stored as a memory region snapshot to ease read by address.
The recover function runs recover flow which reloads the driver and triggers fw
reset if needed.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 98 insertions, 20 deletions

diff --git a/net/core/devlink.c b/net/core/devlink.c
index fd15a66c1d2f..4baf716e535e 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -4518,6 +4518,35 @@ nla_put_failure:
 	return err;
 }
 
+static int devlink_fmsg_dumpit(struct devlink_fmsg *fmsg, struct sk_buff *skb,
+			       struct netlink_callback *cb,
+			       enum devlink_command cmd)
+{
+	int index = cb->args[0];
+	int tmp_index = index;
+	void *hdr;
+	int err;
+
+	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
+			  &devlink_nl_family, NLM_F_ACK | NLM_F_MULTI, cmd);
+	if (!hdr) {
+		err = -EMSGSIZE;
+		goto nla_put_failure;
+	}
+
+	err = devlink_fmsg_prepare_skb(fmsg, skb, &index);
+	if ((err && err != -EMSGSIZE) || tmp_index == index)
+		goto nla_put_failure;
+
+	cb->args[0] = index;
+	genlmsg_end(skb, hdr);
+	return skb->len;
+
+nla_put_failure:
+	genlmsg_cancel(skb, hdr);
+	return err;
+}
+
 struct devlink_health_reporter {
 	struct list_head list;
 	void *priv;
@@ -4750,17 +4779,16 @@ int devlink_health_report(struct devlink_health_reporter *reporter,
 EXPORT_SYMBOL_GPL(devlink_health_report);
 
 static struct devlink_health_reporter *
-devlink_health_reporter_get_from_info(struct devlink *devlink,
-				      struct genl_info *info)
+devlink_health_reporter_get_from_attrs(struct devlink *devlink,
+				       struct nlattr **attrs)
 {
 	struct devlink_health_reporter *reporter;
 	char *reporter_name;
 
-	if (!info->attrs[DEVLINK_ATTR_HEALTH_REPORTER_NAME])
+	if (!attrs[DEVLINK_ATTR_HEALTH_REPORTER_NAME])
 		return NULL;
 
-	reporter_name =
-		nla_data(info->attrs[DEVLINK_ATTR_HEALTH_REPORTER_NAME]);
+	reporter_name = nla_data(attrs[DEVLINK_ATTR_HEALTH_REPORTER_NAME]);
 	mutex_lock(&devlink->reporters_lock);
 	reporter = devlink_health_reporter_find_by_name(devlink, reporter_name);
 	if (reporter)
@@ -4769,6 +4797,48 @@ devlink_health_reporter_get_from_info(struct devlink *devlink,
 	return reporter;
 }
 
+static struct devlink_health_reporter *
+devlink_health_reporter_get_from_info(struct devlink *devlink,
+				      struct genl_info *info)
+{
+	return devlink_health_reporter_get_from_attrs(devlink, info->attrs);
+}
+
+static struct devlink_health_reporter *
+devlink_health_reporter_get_from_cb(struct netlink_callback *cb)
+{
+	struct devlink_health_reporter *reporter;
+	struct devlink *devlink;
+	struct nlattr **attrs;
+	int err;
+
+	attrs = kmalloc_array(DEVLINK_ATTR_MAX + 1, sizeof(*attrs), GFP_KERNEL);
+	if (!attrs)
+		return NULL;
+
+	err = nlmsg_parse_deprecated(cb->nlh,
+				     GENL_HDRLEN + devlink_nl_family.hdrsize,
+				     attrs, DEVLINK_ATTR_MAX,
+				     devlink_nl_family.policy, cb->extack);
+	if (err)
+		goto free;
+
+	mutex_lock(&devlink_mutex);
+	devlink = devlink_get_from_attrs(sock_net(cb->skb->sk), attrs);
+	if (IS_ERR(devlink))
+		goto unlock;
+
+	reporter = devlink_health_reporter_get_from_attrs(devlink, attrs);
+	mutex_unlock(&devlink_mutex);
+	kfree(attrs);
+	return reporter;
+unlock:
+	mutex_unlock(&devlink_mutex);
+free:
+	kfree(attrs);
+	return NULL;
+}
+
 static void
 devlink_health_reporter_put(struct devlink_health_reporter *reporter)
 {
@@ -5004,32 +5074,40 @@ out:
 	return err;
 }
 
-static int devlink_nl_cmd_health_reporter_dump_get_doit(struct sk_buff *skb,
-							struct genl_info *info)
+static int
+devlink_nl_cmd_health_reporter_dump_get_dumpit(struct sk_buff *skb,
+					       struct netlink_callback *cb)
 {
-	struct devlink *devlink = info->user_ptr[0];
 	struct devlink_health_reporter *reporter;
+	u64 start = cb->args[0];
 	int err;
 
-	reporter = devlink_health_reporter_get_from_info(devlink, info);
+	reporter = devlink_health_reporter_get_from_cb(cb);
 	if (!reporter)
 		return -EINVAL;
 
 	if (!reporter->ops->dump) {
-		devlink_health_reporter_put(reporter);
-		return -EOPNOTSUPP;
+		err = -EOPNOTSUPP;
+		goto out;
 	}
-
 	mutex_lock(&reporter->dump_lock);
-	err = devlink_health_do_dump(reporter, NULL);
-	if (err)
-		goto out;
-
-	err = devlink_fmsg_snd(reporter->dump_fmsg, info,
-			       DEVLINK_CMD_HEALTH_REPORTER_DUMP_GET, 0);
+	if (!start) {
+		err = devlink_health_do_dump(reporter, NULL);
+		if (err)
+			goto unlock;
+		cb->args[1] = reporter->dump_ts;
+	}
+	if (!reporter->dump_fmsg || cb->args[1] != reporter->dump_ts) {
+		NL_SET_ERR_MSG_MOD(cb->extack, "Dump trampled, please retry");
+		err = -EAGAIN;
+		goto unlock;
+	}
 
-out:
+	err = devlink_fmsg_dumpit(reporter->dump_fmsg, skb, cb,
+				  DEVLINK_CMD_HEALTH_REPORTER_DUMP_GET);
+unlock:
 	mutex_unlock(&reporter->dump_lock);
+out:
 	devlink_health_reporter_put(reporter);
 	return err;
 }
@@ -5366,7 +5444,7 @@ static const struct genl_ops devlink_nl_ops[] = {
 	{
 		.cmd = DEVLINK_CMD_HEALTH_REPORTER_DUMP_GET,
 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
-		.doit = devlink_nl_cmd_health_reporter_dump_get_doit,
+		.dumpit = devlink_nl_cmd_health_reporter_dump_get_dumpit,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK |
 				  DEVLINK_NL_FLAG_NO_LOCK,