Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 1134 insertions, 0 deletions

diff --git a/net/dsa/switch.c b/net/dsa/switch.c
new file mode 100644
index 000000000..a670a04ed
--- /dev/null
+++ b/net/dsa/switch.c
@@ -0,0 +1,1134 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Handling of a single switch chip, part of a switch fabric
+ *
+ * Copyright (c) 2017 Savoir-faire Linux Inc.
+ *	Vivien Didelot <vivien.didelot@savoirfairelinux.com>
+ */
+
+#include <linux/if_bridge.h>
+#include <linux/netdevice.h>
+#include <linux/notifier.h>
+#include <linux/if_vlan.h>
+#include <net/switchdev.h>
+
+#include "dsa.h"
+#include "netlink.h"
+#include "port.h"
+#include "switch.h"
+#include "tag_8021q.h"
+#include "trace.h"
+#include "user.h"
+
+static unsigned int dsa_switch_fastest_ageing_time(struct dsa_switch *ds,
+						   unsigned int ageing_time)
+{
+	struct dsa_port *dp;
+
+	dsa_switch_for_each_port(dp, ds)
+		if (dp->ageing_time && dp->ageing_time < ageing_time)
+			ageing_time = dp->ageing_time;
+
+	return ageing_time;
+}
+
+static int dsa_switch_ageing_time(struct dsa_switch *ds,
+				  struct dsa_notifier_ageing_time_info *info)
+{
+	unsigned int ageing_time = info->ageing_time;
+
+	if (ds->ageing_time_min && ageing_time < ds->ageing_time_min)
+		return -ERANGE;
+
+	if (ds->ageing_time_max && ageing_time > ds->ageing_time_max)
+		return -ERANGE;
+
+	/* Program the fastest ageing time in case of multiple bridges */
+	ageing_time = dsa_switch_fastest_ageing_time(ds, ageing_time);
+
+	if (ds->ops->set_ageing_time)
+		return ds->ops->set_ageing_time(ds, ageing_time);
+
+	return 0;
+}
+
+static bool dsa_port_mtu_match(struct dsa_port *dp,
+			       struct dsa_notifier_mtu_info *info)
+{
+	return dp == info->dp || dsa_port_is_dsa(dp) || dsa_port_is_cpu(dp);
+}
+
+static int dsa_switch_mtu(struct dsa_switch *ds,
+			  struct dsa_notifier_mtu_info *info)
+{
+	struct dsa_port *dp;
+	int ret;
+
+	if (!ds->ops->port_change_mtu)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_mtu_match(dp, info)) {
+			ret = ds->ops->port_change_mtu(ds, dp->index,
+						       info->mtu);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_bridge_join(struct dsa_switch *ds,
+				  struct dsa_notifier_bridge_info *info)
+{
+	int err;
+
+	if (info->dp->ds == ds) {
+		if (!ds->ops->port_bridge_join)
+			return -EOPNOTSUPP;
+
+		err = ds->ops->port_bridge_join(ds, info->dp->index,
+						info->bridge,
+						&info->tx_fwd_offload,
+						info->extack);
+		if (err)
+			return err;
+	}
+
+	if (info->dp->ds != ds && ds->ops->crosschip_bridge_join) {
+		err = ds->ops->crosschip_bridge_join(ds,
+						     info->dp->ds->dst->index,
+						     info->dp->ds->index,
+						     info->dp->index,
+						     info->bridge,
+						     info->extack);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static int dsa_switch_bridge_leave(struct dsa_switch *ds,
+				   struct dsa_notifier_bridge_info *info)
+{
+	if (info->dp->ds == ds && ds->ops->port_bridge_leave)
+		ds->ops->port_bridge_leave(ds, info->dp->index, info->bridge);
+
+	if (info->dp->ds != ds && ds->ops->crosschip_bridge_leave)
+		ds->ops->crosschip_bridge_leave(ds, info->dp->ds->dst->index,
+						info->dp->ds->index,
+						info->dp->index,
+						info->bridge);
+
+	return 0;
+}
+
+/* Matches for all upstream-facing ports (the CPU port and all upstream-facing
+ * DSA links) that sit between the targeted port on which the notifier was
+ * emitted and its dedicated CPU port.
+ */
+static bool dsa_port_host_address_match(struct dsa_port *dp,
+					const struct dsa_port *targeted_dp)
+{
+	struct dsa_port *cpu_dp = targeted_dp->cpu_dp;
+
+	if (dsa_switch_is_upstream_of(dp->ds, targeted_dp->ds))
+		return dp->index == dsa_towards_port(dp->ds, cpu_dp->ds->index,
+						     cpu_dp->index);
+
+	return false;
+}
+
+static struct dsa_mac_addr *dsa_mac_addr_find(struct list_head *addr_list,
+					      const unsigned char *addr, u16 vid,
+					      struct dsa_db db)
+{
+	struct dsa_mac_addr *a;
+
+	list_for_each_entry(a, addr_list, list)
+		if (ether_addr_equal(a->addr, addr) && a->vid == vid &&
+		    dsa_db_equal(&a->db, &db))
+			return a;
+
+	return NULL;
+}
+
+static int dsa_port_do_mdb_add(struct dsa_port *dp,
+			       const struct switchdev_obj_port_mdb *mdb,
+			       struct dsa_db db)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_mac_addr *a;
+	int port = dp->index;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
+		err = ds->ops->port_mdb_add(ds, port, mdb, db);
+		trace_dsa_mdb_add_hw(dp, mdb->addr, mdb->vid, &db, err);
+
+		return err;
+	}
+
+	mutex_lock(&dp->addr_lists_lock);
+
+	a = dsa_mac_addr_find(&dp->mdbs, mdb->addr, mdb->vid, db);
+	if (a) {
+		refcount_inc(&a->refcount);
+		trace_dsa_mdb_add_bump(dp, mdb->addr, mdb->vid, &db,
+				       &a->refcount);
+		goto out;
+	}
+
+	a = kzalloc_obj(*a);
+	if (!a) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = ds->ops->port_mdb_add(ds, port, mdb, db);
+	trace_dsa_mdb_add_hw(dp, mdb->addr, mdb->vid, &db, err);
+	if (err) {
+		kfree(a);
+		goto out;
+	}
+
+	ether_addr_copy(a->addr, mdb->addr);
+	a->vid = mdb->vid;
+	a->db = db;
+	refcount_set(&a->refcount, 1);
+	list_add_tail(&a->list, &dp->mdbs);
+
+out:
+	mutex_unlock(&dp->addr_lists_lock);
+
+	return err;
+}
+
+static int dsa_port_do_mdb_del(struct dsa_port *dp,
+			       const struct switchdev_obj_port_mdb *mdb,
+			       struct dsa_db db)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_mac_addr *a;
+	int port = dp->index;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
+		err = ds->ops->port_mdb_del(ds, port, mdb, db);
+		trace_dsa_mdb_del_hw(dp, mdb->addr, mdb->vid, &db, err);
+
+		return err;
+	}
+
+	mutex_lock(&dp->addr_lists_lock);
+
+	a = dsa_mac_addr_find(&dp->mdbs, mdb->addr, mdb->vid, db);
+	if (!a) {
+		trace_dsa_mdb_del_not_found(dp, mdb->addr, mdb->vid, &db);
+		err = -ENOENT;
+		goto out;
+	}
+
+	if (!refcount_dec_and_test(&a->refcount)) {
+		trace_dsa_mdb_del_drop(dp, mdb->addr, mdb->vid, &db,
+				       &a->refcount);
+		goto out;
+	}
+
+	err = ds->ops->port_mdb_del(ds, port, mdb, db);
+	trace_dsa_mdb_del_hw(dp, mdb->addr, mdb->vid, &db, err);
+	if (err) {
+		refcount_set(&a->refcount, 1);
+		goto out;
+	}
+
+	list_del(&a->list);
+	kfree(a);
+
+out:
+	mutex_unlock(&dp->addr_lists_lock);
+
+	return err;
+}
+
+static int dsa_port_do_fdb_add(struct dsa_port *dp, const unsigned char *addr,
+			       u16 vid, struct dsa_db db)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_mac_addr *a;
+	int port = dp->index;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
+		err = ds->ops->port_fdb_add(ds, port, addr, vid, db);
+		trace_dsa_fdb_add_hw(dp, addr, vid, &db, err);
+
+		return err;
+	}
+
+	mutex_lock(&dp->addr_lists_lock);
+
+	a = dsa_mac_addr_find(&dp->fdbs, addr, vid, db);
+	if (a) {
+		refcount_inc(&a->refcount);
+		trace_dsa_fdb_add_bump(dp, addr, vid, &db, &a->refcount);
+		goto out;
+	}
+
+	a = kzalloc_obj(*a);
+	if (!a) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = ds->ops->port_fdb_add(ds, port, addr, vid, db);
+	trace_dsa_fdb_add_hw(dp, addr, vid, &db, err);
+	if (err) {
+		kfree(a);
+		goto out;
+	}
+
+	ether_addr_copy(a->addr, addr);
+	a->vid = vid;
+	a->db = db;
+	refcount_set(&a->refcount, 1);
+	list_add_tail(&a->list, &dp->fdbs);
+
+out:
+	mutex_unlock(&dp->addr_lists_lock);
+
+	return err;
+}
+
+static int dsa_port_do_fdb_del(struct dsa_port *dp, const unsigned char *addr,
+			       u16 vid, struct dsa_db db)
+{
+	struct dsa_switch *ds = dp->ds;
+	struct dsa_mac_addr *a;
+	int port = dp->index;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
+		err = ds->ops->port_fdb_del(ds, port, addr, vid, db);
+		trace_dsa_fdb_del_hw(dp, addr, vid, &db, err);
+
+		return err;
+	}
+
+	mutex_lock(&dp->addr_lists_lock);
+
+	a = dsa_mac_addr_find(&dp->fdbs, addr, vid, db);
+	if (!a) {
+		trace_dsa_fdb_del_not_found(dp, addr, vid, &db);
+		err = -ENOENT;
+		goto out;
+	}
+
+	if (!refcount_dec_and_test(&a->refcount)) {
+		trace_dsa_fdb_del_drop(dp, addr, vid, &db, &a->refcount);
+		goto out;
+	}
+
+	err = ds->ops->port_fdb_del(ds, port, addr, vid, db);
+	trace_dsa_fdb_del_hw(dp, addr, vid, &db, err);
+	if (err) {
+		refcount_set(&a->refcount, 1);
+		goto out;
+	}
+
+	list_del(&a->list);
+	kfree(a);
+
+out:
+	mutex_unlock(&dp->addr_lists_lock);
+
+	return err;
+}
+
+static int dsa_switch_do_lag_fdb_add(struct dsa_switch *ds, struct dsa_lag *lag,
+				     const unsigned char *addr, u16 vid,
+				     struct dsa_db db)
+{
+	struct dsa_mac_addr *a;
+	int err = 0;
+
+	mutex_lock(&lag->fdb_lock);
+
+	a = dsa_mac_addr_find(&lag->fdbs, addr, vid, db);
+	if (a) {
+		refcount_inc(&a->refcount);
+		trace_dsa_lag_fdb_add_bump(lag->dev, addr, vid, &db,
+					   &a->refcount);
+		goto out;
+	}
+
+	a = kzalloc_obj(*a);
+	if (!a) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = ds->ops->lag_fdb_add(ds, *lag, addr, vid, db);
+	trace_dsa_lag_fdb_add_hw(lag->dev, addr, vid, &db, err);
+	if (err) {
+		kfree(a);
+		goto out;
+	}
+
+	ether_addr_copy(a->addr, addr);
+	a->vid = vid;
+	a->db = db;
+	refcount_set(&a->refcount, 1);
+	list_add_tail(&a->list, &lag->fdbs);
+
+out:
+	mutex_unlock(&lag->fdb_lock);
+
+	return err;
+}
+
+static int dsa_switch_do_lag_fdb_del(struct dsa_switch *ds, struct dsa_lag *lag,
+				     const unsigned char *addr, u16 vid,
+				     struct dsa_db db)
+{
+	struct dsa_mac_addr *a;
+	int err = 0;
+
+	mutex_lock(&lag->fdb_lock);
+
+	a = dsa_mac_addr_find(&lag->fdbs, addr, vid, db);
+	if (!a) {
+		trace_dsa_lag_fdb_del_not_found(lag->dev, addr, vid, &db);
+		err = -ENOENT;
+		goto out;
+	}
+
+	if (!refcount_dec_and_test(&a->refcount)) {
+		trace_dsa_lag_fdb_del_drop(lag->dev, addr, vid, &db,
+					   &a->refcount);
+		goto out;
+	}
+
+	err = ds->ops->lag_fdb_del(ds, *lag, addr, vid, db);
+	trace_dsa_lag_fdb_del_hw(lag->dev, addr, vid, &db, err);
+	if (err) {
+		refcount_set(&a->refcount, 1);
+		goto out;
+	}
+
+	list_del(&a->list);
+	kfree(a);
+
+out:
+	mutex_unlock(&lag->fdb_lock);
+
+	return err;
+}
+
+static int dsa_switch_host_fdb_add(struct dsa_switch *ds,
+				   struct dsa_notifier_fdb_info *info)
+{
+	struct dsa_port *dp;
+	int err = 0;
+
+	if (!ds->ops->port_fdb_add)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_address_match(dp, info->dp)) {
+			if (dsa_port_is_cpu(dp) && info->dp->cpu_port_in_lag) {
+				err = dsa_switch_do_lag_fdb_add(ds, dp->lag,
+								info->addr,
+								info->vid,
+								info->db);
+			} else {
+				err = dsa_port_do_fdb_add(dp, info->addr,
+							  info->vid, info->db);
+			}
+			if (err)
+				break;
+		}
+	}
+
+	return err;
+}
+
+static int dsa_switch_host_fdb_del(struct dsa_switch *ds,
+				   struct dsa_notifier_fdb_info *info)
+{
+	struct dsa_port *dp;
+	int err = 0;
+
+	if (!ds->ops->port_fdb_del)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_address_match(dp, info->dp)) {
+			if (dsa_port_is_cpu(dp) && info->dp->cpu_port_in_lag) {
+				err = dsa_switch_do_lag_fdb_del(ds, dp->lag,
+								info->addr,
+								info->vid,
+								info->db);
+			} else {
+				err = dsa_port_do_fdb_del(dp, info->addr,
+							  info->vid, info->db);
+			}
+			if (err)
+				break;
+		}
+	}
+
+	return err;
+}
+
+static int dsa_switch_fdb_add(struct dsa_switch *ds,
+			      struct dsa_notifier_fdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
+	struct dsa_port *dp = dsa_to_port(ds, port);
+
+	if (!ds->ops->port_fdb_add)
+		return -EOPNOTSUPP;
+
+	return dsa_port_do_fdb_add(dp, info->addr, info->vid, info->db);
+}
+
+static int dsa_switch_fdb_del(struct dsa_switch *ds,
+			      struct dsa_notifier_fdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
+	struct dsa_port *dp = dsa_to_port(ds, port);
+
+	if (!ds->ops->port_fdb_del)
+		return -EOPNOTSUPP;
+
+	return dsa_port_do_fdb_del(dp, info->addr, info->vid, info->db);
+}
+
+static int dsa_switch_lag_fdb_add(struct dsa_switch *ds,
+				  struct dsa_notifier_lag_fdb_info *info)
+{
+	struct dsa_port *dp;
+
+	if (!ds->ops->lag_fdb_add)
+		return -EOPNOTSUPP;
+
+	/* Notify switch only if it has a port in this LAG */
+	dsa_switch_for_each_port(dp, ds)
+		if (dsa_port_offloads_lag(dp, info->lag))
+			return dsa_switch_do_lag_fdb_add(ds, info->lag,
+							 info->addr, info->vid,
+							 info->db);
+
+	return 0;
+}
+
+static int dsa_switch_lag_fdb_del(struct dsa_switch *ds,
+				  struct dsa_notifier_lag_fdb_info *info)
+{
+	struct dsa_port *dp;
+
+	if (!ds->ops->lag_fdb_del)
+		return -EOPNOTSUPP;
+
+	/* Notify switch only if it has a port in this LAG */
+	dsa_switch_for_each_port(dp, ds)
+		if (dsa_port_offloads_lag(dp, info->lag))
+			return dsa_switch_do_lag_fdb_del(ds, info->lag,
+							 info->addr, info->vid,
+							 info->db);
+
+	return 0;
+}
+
+static int dsa_switch_lag_change(struct dsa_switch *ds,
+				 struct dsa_notifier_lag_info *info)
+{
+	if (info->dp->ds == ds && ds->ops->port_lag_change)
+		return ds->ops->port_lag_change(ds, info->dp->index);
+
+	if (info->dp->ds != ds && ds->ops->crosschip_lag_change)
+		return ds->ops->crosschip_lag_change(ds, info->dp->ds->index,
+						     info->dp->index);
+
+	return 0;
+}
+
+static int dsa_switch_lag_join(struct dsa_switch *ds,
+			       struct dsa_notifier_lag_info *info)
+{
+	if (info->dp->ds == ds && ds->ops->port_lag_join)
+		return ds->ops->port_lag_join(ds, info->dp->index, info->lag,
+					      info->info, info->extack);
+
+	if (info->dp->ds != ds && ds->ops->crosschip_lag_join)
+		return ds->ops->crosschip_lag_join(ds, info->dp->ds->index,
+						   info->dp->index, info->lag,
+						   info->info, info->extack);
+
+	return -EOPNOTSUPP;
+}
+
+static int dsa_switch_lag_leave(struct dsa_switch *ds,
+				struct dsa_notifier_lag_info *info)
+{
+	if (info->dp->ds == ds && ds->ops->port_lag_leave)
+		return ds->ops->port_lag_leave(ds, info->dp->index, info->lag);
+
+	if (info->dp->ds != ds && ds->ops->crosschip_lag_leave)
+		return ds->ops->crosschip_lag_leave(ds, info->dp->ds->index,
+						    info->dp->index, info->lag);
+
+	return -EOPNOTSUPP;
+}
+
+static int dsa_switch_mdb_add(struct dsa_switch *ds,
+			      struct dsa_notifier_mdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
+	struct dsa_port *dp = dsa_to_port(ds, port);
+
+	if (!ds->ops->port_mdb_add)
+		return -EOPNOTSUPP;
+
+	return dsa_port_do_mdb_add(dp, info->mdb, info->db);
+}
+
+static int dsa_switch_mdb_del(struct dsa_switch *ds,
+			      struct dsa_notifier_mdb_info *info)
+{
+	int port = dsa_towards_port(ds, info->dp->ds->index, info->dp->index);
+	struct dsa_port *dp = dsa_to_port(ds, port);
+
+	if (!ds->ops->port_mdb_del)
+		return -EOPNOTSUPP;
+
+	return dsa_port_do_mdb_del(dp, info->mdb, info->db);
+}
+
+static int dsa_switch_host_mdb_add(struct dsa_switch *ds,
+				   struct dsa_notifier_mdb_info *info)
+{
+	struct dsa_port *dp;
+	int err = 0;
+
+	if (!ds->ops->port_mdb_add)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_address_match(dp, info->dp)) {
+			err = dsa_port_do_mdb_add(dp, info->mdb, info->db);
+			if (err)
+				break;
+		}
+	}
+
+	return err;
+}
+
+static int dsa_switch_host_mdb_del(struct dsa_switch *ds,
+				   struct dsa_notifier_mdb_info *info)
+{
+	struct dsa_port *dp;
+	int err = 0;
+
+	if (!ds->ops->port_mdb_del)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_address_match(dp, info->dp)) {
+			err = dsa_port_do_mdb_del(dp, info->mdb, info->db);
+			if (err)
+				break;
+		}
+	}
+
+	return err;
+}
+
+/* Port VLANs match on the targeted port and on all DSA ports */
+static bool dsa_port_vlan_match(struct dsa_port *dp,
+				struct dsa_notifier_vlan_info *info)
+{
+	return dsa_port_is_dsa(dp) || dp == info->dp;
+}
+
+/* Host VLANs match on the targeted port's CPU port, and on all DSA ports
+ * (upstream and downstream) of that switch and its upstream switches.
+ */
+static bool dsa_port_host_vlan_match(struct dsa_port *dp,
+				     const struct dsa_port *targeted_dp)
+{
+	struct dsa_port *cpu_dp = targeted_dp->cpu_dp;
+
+	if (dsa_switch_is_upstream_of(dp->ds, targeted_dp->ds))
+		return dsa_port_is_dsa(dp) || dp == cpu_dp;
+
+	return false;
+}
+
+struct dsa_vlan *dsa_vlan_find(struct list_head *vlan_list,
+			       const struct switchdev_obj_port_vlan *vlan)
+{
+	struct dsa_vlan *v;
+
+	list_for_each_entry(v, vlan_list, list)
+		if (v->vid == vlan->vid)
+			return v;
+
+	return NULL;
+}
+
+static int dsa_port_do_vlan_add(struct dsa_port *dp,
+				const struct switchdev_obj_port_vlan *vlan,
+				struct netlink_ext_ack *extack)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+	struct dsa_vlan *v;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports. */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
+		err = ds->ops->port_vlan_add(ds, port, vlan, extack);
+		trace_dsa_vlan_add_hw(dp, vlan, err);
+
+		return err;
+	}
+
+	/* No need to propagate on shared ports the existing VLANs that were
+	 * re-notified after just the flags have changed. This would cause a
+	 * refcount bump which we need to avoid, since it unbalances the
+	 * additions with the deletions.
+	 */
+	if (vlan->changed)
+		return 0;
+
+	mutex_lock(&dp->vlans_lock);
+
+	v = dsa_vlan_find(&dp->vlans, vlan);
+	if (v) {
+		refcount_inc(&v->refcount);
+		trace_dsa_vlan_add_bump(dp, vlan, &v->refcount);
+		goto out;
+	}
+
+	v = kzalloc_obj(*v);
+	if (!v) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = ds->ops->port_vlan_add(ds, port, vlan, extack);
+	trace_dsa_vlan_add_hw(dp, vlan, err);
+	if (err) {
+		kfree(v);
+		goto out;
+	}
+
+	v->vid = vlan->vid;
+	refcount_set(&v->refcount, 1);
+	list_add_tail(&v->list, &dp->vlans);
+
+out:
+	mutex_unlock(&dp->vlans_lock);
+
+	return err;
+}
+
+static int dsa_port_do_vlan_del(struct dsa_port *dp,
+				const struct switchdev_obj_port_vlan *vlan)
+{
+	struct dsa_switch *ds = dp->ds;
+	int port = dp->index;
+	struct dsa_vlan *v;
+	int err = 0;
+
+	/* No need to bother with refcounting for user ports */
+	if (!(dsa_port_is_cpu(dp) || dsa_port_is_dsa(dp))) {
+		err = ds->ops->port_vlan_del(ds, port, vlan);
+		trace_dsa_vlan_del_hw(dp, vlan, err);
+
+		return err;
+	}
+
+	mutex_lock(&dp->vlans_lock);
+
+	v = dsa_vlan_find(&dp->vlans, vlan);
+	if (!v) {
+		trace_dsa_vlan_del_not_found(dp, vlan);
+		err = -ENOENT;
+		goto out;
+	}
+
+	if (!refcount_dec_and_test(&v->refcount)) {
+		trace_dsa_vlan_del_drop(dp, vlan, &v->refcount);
+		goto out;
+	}
+
+	err = ds->ops->port_vlan_del(ds, port, vlan);
+	trace_dsa_vlan_del_hw(dp, vlan, err);
+	if (err) {
+		refcount_set(&v->refcount, 1);
+		goto out;
+	}
+
+	list_del(&v->list);
+	kfree(v);
+
+out:
+	mutex_unlock(&dp->vlans_lock);
+
+	return err;
+}
+
+static int dsa_switch_vlan_add(struct dsa_switch *ds,
+			       struct dsa_notifier_vlan_info *info)
+{
+	struct dsa_port *dp;
+	int err;
+
+	if (!ds->ops->port_vlan_add)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_vlan_match(dp, info)) {
+			err = dsa_port_do_vlan_add(dp, info->vlan,
+						   info->extack);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_vlan_del(struct dsa_switch *ds,
+			       struct dsa_notifier_vlan_info *info)
+{
+	struct dsa_port *dp;
+	int err;
+
+	if (!ds->ops->port_vlan_del)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_vlan_match(dp, info)) {
+			err = dsa_port_do_vlan_del(dp, info->vlan);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_host_vlan_add(struct dsa_switch *ds,
+				    struct dsa_notifier_vlan_info *info)
+{
+	struct dsa_port *dp;
+	int err;
+
+	if (!ds->ops->port_vlan_add)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_vlan_match(dp, info->dp)) {
+			err = dsa_port_do_vlan_add(dp, info->vlan,
+						   info->extack);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_host_vlan_del(struct dsa_switch *ds,
+				    struct dsa_notifier_vlan_info *info)
+{
+	struct dsa_port *dp;
+	int err;
+
+	if (!ds->ops->port_vlan_del)
+		return -EOPNOTSUPP;
+
+	dsa_switch_for_each_port(dp, ds) {
+		if (dsa_port_host_vlan_match(dp, info->dp)) {
+			err = dsa_port_do_vlan_del(dp, info->vlan);
+			if (err)
+				return err;
+		}
+	}
+
+	return 0;
+}
+
+static int dsa_switch_change_tag_proto(struct dsa_switch *ds,
+				       struct dsa_notifier_tag_proto_info *info)
+{
+	const struct dsa_device_ops *tag_ops = info->tag_ops;
+	struct dsa_port *dp, *cpu_dp;
+	int err;
+
+	if (!ds->ops->change_tag_protocol)
+		return -EOPNOTSUPP;
+
+	ASSERT_RTNL();
+
+	err = ds->ops->change_tag_protocol(ds, tag_ops->proto);
+	if (err)
+		return err;
+
+	dsa_switch_for_each_cpu_port(cpu_dp, ds)
+		dsa_port_set_tag_protocol(cpu_dp, tag_ops);
+
+	/* Now that changing the tag protocol can no longer fail, let's update
+	 * the remaining bits which are "duplicated for faster access", and the
+	 * bits that depend on the tagger, such as the MTU.
+	 */
+	dsa_switch_for_each_user_port(dp, ds) {
+		struct net_device *user = dp->user;
+
+		dsa_user_setup_tagger(user);
+
+		/* rtnl_mutex is held in dsa_tree_change_tag_proto */
+		dsa_user_change_mtu(user, user->mtu);
+	}
+
+	return 0;
+}
+
+/* We use the same cross-chip notifiers to inform both the tagger side, as well
+ * as the switch side, of connection and disconnection events.
+ * Since ds->tagger_data is owned by the tagger, it isn't a hard error if the
+ * switch side doesn't support connecting to this tagger, and therefore, the
+ * fact that we don't disconnect the tagger side doesn't constitute a memory
+ * leak: the tagger will still operate with persistent per-switch memory, just
+ * with the switch side unconnected to it. What does constitute a hard error is
+ * when the switch side supports connecting but fails.
+ */
+static int
+dsa_switch_connect_tag_proto(struct dsa_switch *ds,
+			     struct dsa_notifier_tag_proto_info *info)
+{
+	const struct dsa_device_ops *tag_ops = info->tag_ops;
+	int err;
+
+	/* Notify the new tagger about the connection to this switch */
+	if (tag_ops->connect) {
+		err = tag_ops->connect(ds);
+		if (err)
+			return err;
+	}
+
+	if (!ds->ops->connect_tag_protocol)
+		return -EOPNOTSUPP;
+
+	/* Notify the switch about the connection to the new tagger */
+	err = ds->ops->connect_tag_protocol(ds, tag_ops->proto);
+	if (err) {
+		/* Revert the new tagger's connection to this tree */
+		if (tag_ops->disconnect)
+			tag_ops->disconnect(ds);
+		return err;
+	}
+
+	return 0;
+}
+
+static int
+dsa_switch_disconnect_tag_proto(struct dsa_switch *ds,
+				struct dsa_notifier_tag_proto_info *info)
+{
+	const struct dsa_device_ops *tag_ops = info->tag_ops;
+
+	/* Notify the tagger about the disconnection from this switch */
+	if (tag_ops->disconnect && ds->tagger_data)
+		tag_ops->disconnect(ds);
+
+	/* No need to notify the switch, since it shouldn't have any
+	 * resources to tear down
+	 */
+	return 0;
+}
+
+static int
+dsa_switch_conduit_state_change(struct dsa_switch *ds,
+				struct dsa_notifier_conduit_state_info *info)
+{
+	if (!ds->ops->conduit_state_change)
+		return 0;
+
+	ds->ops->conduit_state_change(ds, info->conduit, info->operational);
+
+	return 0;
+}
+
+static int dsa_switch_event(struct notifier_block *nb,
+			    unsigned long event, void *info)
+{
+	struct dsa_switch *ds = container_of(nb, struct dsa_switch, nb);
+	int err;
+
+	switch (event) {
+	case DSA_NOTIFIER_AGEING_TIME:
+		err = dsa_switch_ageing_time(ds, info);
+		break;
+	case DSA_NOTIFIER_BRIDGE_JOIN:
+		err = dsa_switch_bridge_join(ds, info);
+		break;
+	case DSA_NOTIFIER_BRIDGE_LEAVE:
+		err = dsa_switch_bridge_leave(ds, info);
+		break;
+	case DSA_NOTIFIER_FDB_ADD:
+		err = dsa_switch_fdb_add(ds, info);
+		break;
+	case DSA_NOTIFIER_FDB_DEL:
+		err = dsa_switch_fdb_del(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_FDB_ADD:
+		err = dsa_switch_host_fdb_add(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_FDB_DEL:
+		err = dsa_switch_host_fdb_del(ds, info);
+		break;
+	case DSA_NOTIFIER_LAG_FDB_ADD:
+		err = dsa_switch_lag_fdb_add(ds, info);
+		break;
+	case DSA_NOTIFIER_LAG_FDB_DEL:
+		err = dsa_switch_lag_fdb_del(ds, info);
+		break;
+	case DSA_NOTIFIER_LAG_CHANGE:
+		err = dsa_switch_lag_change(ds, info);
+		break;
+	case DSA_NOTIFIER_LAG_JOIN:
+		err = dsa_switch_lag_join(ds, info);
+		break;
+	case DSA_NOTIFIER_LAG_LEAVE:
+		err = dsa_switch_lag_leave(ds, info);
+		break;
+	case DSA_NOTIFIER_MDB_ADD:
+		err = dsa_switch_mdb_add(ds, info);
+		break;
+	case DSA_NOTIFIER_MDB_DEL:
+		err = dsa_switch_mdb_del(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_MDB_ADD:
+		err = dsa_switch_host_mdb_add(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_MDB_DEL:
+		err = dsa_switch_host_mdb_del(ds, info);
+		break;
+	case DSA_NOTIFIER_VLAN_ADD:
+		err = dsa_switch_vlan_add(ds, info);
+		break;
+	case DSA_NOTIFIER_VLAN_DEL:
+		err = dsa_switch_vlan_del(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_VLAN_ADD:
+		err = dsa_switch_host_vlan_add(ds, info);
+		break;
+	case DSA_NOTIFIER_HOST_VLAN_DEL:
+		err = dsa_switch_host_vlan_del(ds, info);
+		break;
+	case DSA_NOTIFIER_MTU:
+		err = dsa_switch_mtu(ds, info);
+		break;
+	case DSA_NOTIFIER_TAG_PROTO:
+		err = dsa_switch_change_tag_proto(ds, info);
+		break;
+	case DSA_NOTIFIER_TAG_PROTO_CONNECT:
+		err = dsa_switch_connect_tag_proto(ds, info);
+		break;
+	case DSA_NOTIFIER_TAG_PROTO_DISCONNECT:
+		err = dsa_switch_disconnect_tag_proto(ds, info);
+		break;
+	case DSA_NOTIFIER_TAG_8021Q_VLAN_ADD:
+		err = dsa_switch_tag_8021q_vlan_add(ds, info);
+		break;
+	case DSA_NOTIFIER_TAG_8021Q_VLAN_DEL:
+		err = dsa_switch_tag_8021q_vlan_del(ds, info);
+		break;
+	case DSA_NOTIFIER_CONDUIT_STATE_CHANGE:
+		err = dsa_switch_conduit_state_change(ds, info);
+		break;
+	default:
+		err = -EOPNOTSUPP;
+		break;
+	}
+
+	if (err)
+		dev_dbg(ds->dev, "breaking chain for DSA event %lu (%d)\n",
+			event, err);
+
+	return notifier_from_errno(err);
+}
+
+/**
+ * dsa_tree_notify - Execute code for all switches in a DSA switch tree.
+ * @dst: collection of struct dsa_switch devices to notify.
+ * @e: event, must be of type DSA_NOTIFIER_*
+ * @v: event-specific value.
+ *
+ * Given a struct dsa_switch_tree, this can be used to run a function once for
+ * each member DSA switch. The other alternative of traversing the tree is only
+ * through its ports list, which does not uniquely list the switches.
+ */
+int dsa_tree_notify(struct dsa_switch_tree *dst, unsigned long e, void *v)
+{
+	struct raw_notifier_head *nh = &dst->nh;
+	int err;
+
+	err = raw_notifier_call_chain(nh, e, v);
+
+	return notifier_to_errno(err);
+}
+
+/**
+ * dsa_broadcast - Notify all DSA trees in the system.
+ * @e: event, must be of type DSA_NOTIFIER_*
+ * @v: event-specific value.
+ *
+ * Can be used to notify the switching fabric of events such as cross-chip
+ * bridging between disjoint trees (such as islands of tagger-compatible
+ * switches bridged by an incompatible middle switch).
+ *
+ * WARNING: this function is not reliable during probe time, because probing
+ * between trees is asynchronous and not all DSA trees might have probed.
+ */
+int dsa_broadcast(unsigned long e, void *v)
+{
+	struct dsa_switch_tree *dst;
+	int err = 0;
+
+	list_for_each_entry(dst, &dsa_tree_list, list) {
+		err = dsa_tree_notify(dst, e, v);
+		if (err)
+			break;
+	}
+
+	return err;
+}
+
+int dsa_switch_register_notifier(struct dsa_switch *ds)
+{
+	ds->nb.notifier_call = dsa_switch_event;
+
+	return raw_notifier_chain_register(&ds->dst->nh, &ds->nb);
+}
+
+void dsa_switch_unregister_notifier(struct dsa_switch *ds)
+{
+	int err;
+
+	err = raw_notifier_chain_unregister(&ds->dst->nh, &ds->nb);
+	if (err)
+		dev_err(ds->dev, "failed to unregister notifier (%d)\n", err);
+}