Commit graph

30 commits

Author SHA1 Message Date
Jiri Pirko
2557396808 devlink: convert linecards dump to devlink_nl_instance_iter_dump()
Benefit from recently introduced instance iteration and convert
linecards .dumpit generic netlink callback to use it.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-19 19:08:38 -08:00
Jiri Pirko
e994a75fb7 devlink: remove reporter reference counting
As long as the reporter life time is protected by devlink instance
lock, the reference counting is no longer needed. Remove it.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-19 19:08:38 -08:00
Jiri Pirko
9f167327ef devlink: remove devl*_port_health_reporter_destroy()
Remove port-specific health reporter destroy function as it is
currently the same as the instance one so no longer needed. Inline
__devlink_health_reporter_destroy() as it is no longer called from
multiple places.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-19 19:08:37 -08:00
Jiri Pirko
1dea3b4e4c devlink: remove reporters_lock
Similar to other devlink objects, rely on devlink instance lock
and remove object specific reporters_lock.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-19 19:08:37 -08:00
Jiri Pirko
dfdfd1305d devlink: protect health reporter operation with instance lock
Similar to other devlink objects, protect the reporters list
by devlink instance lock. Alongside add unlocked versions
of health reporter create/destroy functions and use them in drivers
on call paths where the instance lock is held.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-19 19:08:37 -08:00
Jiri Pirko
3a10173f48 devlink: remove linecard reference counting
As long as the linecard life time is protected by devlink instance
lock, the reference counting is no longer needed. Remove it.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-19 19:08:37 -08:00
Jiri Pirko
5cc9049cb9 devlink: remove linecards lock
Similar to other devlink objects, convert the linecards list to be
protected by devlink instance lock. Alongside with that rename the
create/destroy() functions to devl_* to indicate the devlink instance
lock needs to be held while calling them.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-19 19:08:37 -08:00
Dan Carpenter
501543b4ff devlink: remove some unnecessary code
This code checks if (attrs[DEVLINK_ATTR_TRAP_POLICER_ID]) twice.  Once
at the start of the function and then a couple lines later.  Delete the
second check since that one must be true.

Because the second condition is always true, it means the:

	policer_item = group_item->policer_item;

assignment is immediately over-written.  Delete that as well.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/Y8EJz8oxpMhfiPUb@kili
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-01-17 10:02:49 +01:00
Jakub Kicinski
93e71edfd9 devlink: keep the instance mutex alive until references are gone
The reference needs to keep the instance memory around, but also
the instance lock must remain valid. Users will take the lock,
check registration status and release the lock. mutex_destroy()
etc. belong in the same place as the freeing of the memory.

Unfortunately lockdep_unregister_key() sleeps so we need
to switch the an rcu_work.

Note that the problem is a bit hard to repro, because
devlink_pernet_pre_exit() iterates over registered instances.
AFAIU the instances must get devlink_free()d concurrently with
the namespace getting deleted for the problem to occur.

Reported-by: syzbot+d94d214ea473e218fc89@syzkaller.appspotmail.com
Reported-by: syzbot+9f0dd863b87113935acf@syzkaller.appspotmail.com
Fixes: 9053637e0d ("devlink: remove the registration guarantee of references")
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20230111042908.988199-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-11 20:49:32 -08:00
Jakub Kicinski
1d18bb1a4d devlink: allow registering parameters after the instance
It's most natural to register the instance first and then its
subobjects. Now that we can use the instance lock to protect
the atomicity of all init - it should also be safe.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-06 12:56:19 +00:00
Jakub Kicinski
6ef8f7da92 devlink: don't require setting features before registration
Requiring devlink_set_features() to be run before devlink is
registered is overzealous. devlink_set_features() itself is
a leftover from old workarounds which were trying to prevent
initiating reload before probe was complete.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-06 12:56:19 +00:00
Jakub Kicinski
9053637e0d devlink: remove the registration guarantee of references
The objective of exposing the devlink instance locks to
drivers was to let them use these locks to prevent user space
from accessing the device before it's fully initialized.
This is difficult because devlink_unregister() waits for all
references to be released, meaning that devlink_unregister()
can't itself be called under the instance lock.

To avoid this issue devlink_register() was moved after subobject
registration a while ago. Unfortunately the netdev paths get
a hold of the devlink instances _before_ they are registered.
Ideally netdev should wait for devlink init to finish (synchronizing
on the instance lock). This can't work because we don't know if the
instance will _ever_ be registered (in case of failures it may not).
The other option of returning an error until devlink_register()
is called is unappealing (user space would get a notification
netdev exist but would have to wait arbitrary amount of time
before accessing some of its attributes).

Weaken the guarantees of the devlink references.

Holding a reference will now only guarantee that the memory
of the object is around. Another way of looking at it is that
the reference now protects the object not its "registered" status.
Use devlink instance lock to synchronize unregistration.

This implies that releasing of the "main" reference of the devlink
instance moves from devlink_unregister() to devlink_free().

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-06 12:56:19 +00:00
Jakub Kicinski
ed539ba614 devlink: always check if the devlink instance is registered
Always check under the instance lock whether the devlink instance
is still / already registered.

This is a no-op for the most part, as the unregistration path currently
waits for all references. On the init path, however, we may temporarily
open up a race with netdev code, if netdevs are registered before the
devlink instance. This is temporary, the next change fixes it, and this
commit has been split out for the ease of review.

Note that in case of iterating over sub-objects which have their
own lock (regions and line cards) we assume an implicit dependency
between those objects existing and devlink unregistration.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-06 12:56:19 +00:00
Jakub Kicinski
870c7ad4a5 devlink: protect devlink->dev by the instance lock
devlink->dev is assumed to be always valid as long as any
outstanding reference to the devlink instance exists.

In prep for weakening of the references take the instance lock.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-06 12:56:18 +00:00
Jakub Kicinski
7a54a5195b devlink: update the code in netns move to latest helpers
devlink_pernet_pre_exit() is the only obvious place which takes
the instance lock without using the devl_ helpers. Update the code
and move the error print after releasing the reference
(having unlock and put together feels slightly idiomatic).

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-06 12:56:18 +00:00
Jakub Kicinski
d772781964 devlink: bump the instance index directly when iterating
xa_find_after() is designed to handle multi-index entries correctly.
If a xarray has two entries one which spans indexes 0-3 and one at
index 4 xa_find_after(0) will return the entry at index 4.

Having to juggle the two callbacks, however, is unnecessary in case
of the devlink xarray, as there is 1:1 relationship with indexes.

Always use xa_find() and increment the index manually.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-06 12:56:18 +00:00
Jakub Kicinski
5ce76d78b9 devlink: convert remaining dumps to the by-instance scheme
Soon we'll have to check if a devlink instance is alive after
locking it. Convert to the by-instance dumping scheme to make
refactoring easier.

Most of the subobject code no longer has to worry about any devlink
locking / lifetime rules (the only ones that still do are the two subject
types which stubbornly use their own locking). Both dump and do callbacks
are given a devlink instance which is already locked and good-to-access
(do from the .pre_doit handler, dump from the new dump indirection).

Note that we'll now check presence of an op (e.g. for sb_pool_get)
under the devlink instance lock, that will soon be necessary anyway,
because we don't hold refs on the driver modules so the memory
in which ops live may be gone for a dead instance, after upcoming
locking changes.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:40 -08:00
Jakub Kicinski
07f3af6608 devlink: add by-instance dump infra
Most dumpit implementations walk the devlink instances.
This requires careful lock taking and reference dropping.
Factor the loop out and provide just a callback to handle
a single instance dump.

Convert one user as an example, other users converted
in the next change.

Slightly inspired by ethtool netlink code.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:39 -08:00
Jakub Kicinski
e4d5015bc1 devlink: uniformly take the devlink instance lock in the dump loop
Move the lock taking out of devlink_nl_cmd_region_get_devlink_dumpit().
This way all dumps will take the instance lock in the main iteration
loop directly, making refactoring and reading the code easier.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:39 -08:00
Jakub Kicinski
c9666bac53 devlink: restart dump based on devlink instance ids (function)
Use xarray id for cases of sub-objects which are iterated in
a function.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:39 -08:00
Jakub Kicinski
a8f947073f devlink: restart dump based on devlink instance ids (nested)
Use xarray id for cases of simple sub-object iteration.
We'll now use the state->instance for the devlink instances
and state->idx for subobject index.

Moving the definition of idx into the inner loop makes sense,
so while at it also move other sub-object local variables into
the loop.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:39 -08:00
Jakub Kicinski
731d69a6bd devlink: restart dump based on devlink instance ids (simple)
xarray gives each devlink instance an id and allows us to restart
walk based on that id quite neatly. This is nice both from the
perspective of code brevity and from the stability of the dump
(devlink instances disappearing from before the resumption point
will not cause inconsistent dumps).

This patch takes care of simple cases where state->idx counts
devlink instances only.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:39 -08:00
Jakub Kicinski
a0e13dfdc3 devlink: health: combine loops in dump
Walk devlink instances only once. Dump the instance reporters
and port reporters before moving to the next instance.
User space should not depend on ordering of messages.

This will make improving stability of the walk easier.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:39 -08:00
Jakub Kicinski
8861c0933c devlink: drop the filter argument from devlinks_xa_find_get
Looks like devlinks_xa_find_get() was intended to get the mark
from the @filter argument. It doesn't actually use @filter, passing
DEVLINK_REGISTERED to xa_find_fn() directly. Walking marks other
than registered is unlikely so drop @filter argument completely.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:39 -08:00
Jakub Kicinski
20615659b5 devlink: remove start variables from dumps
The start variables made the code clearer when we had to access
cb->args[0] directly, as the name args doesn't explain much.
Now that we use a structure to hold state this seems no longer
needed.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:39 -08:00
Jakub Kicinski
3015f82249 devlink: use an explicit structure for dump context
Create a dump context structure instead of using cb->args
as an unsigned long array. This is a pure conversion which
is intended to be as much of a noop as possible.
Subsequent changes will use this to simplify the code.

The two non-trivial parts are:
 - devlink_nl_cmd_health_reporter_dump_get_dumpit() checks args[0]
   to see if devlink_fmsg_dumpit() has already been called (whether
   this is the first msg), but doesn't use the exact value, so we
   can drop the local variable there already
 - devlink_nl_cmd_region_read_dumpit() uses args[0] for address
   but we'll use args[1] now, shouldn't matter

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:39 -08:00
Jakub Kicinski
623cd13b16 devlink: split out netlink code
Move out the netlink glue into a separate file.
Leave the ops in the old file because we'd have to export a ton
of functions. Going forward we should switch to split ops which
will let us to put the new ops in the netlink.c file.

Pure code move, no functional changes.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:39 -08:00
Jakub Kicinski
687125b579 devlink: split out core code
Move core code into a separate file. It's spread around the main
file which makes refactoring and figuring out how devlink works
harder.

Move the xarray, all the most core devlink instance code out like
locking, ref counting, alloc, register, etc. Leave port stuff in
leftover.c, if we want to move port code it'd probably be to its
own file.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:13:31 -08:00
Jakub Kicinski
e50ef40f9a devlink: rename devlink_netdevice_event -> devlink_port_netdevice_event
To make the upcoming change a pure(er?) code move rename
devlink_netdevice_event -> devlink_port_netdevice_event.
This makes it clear that it only touches ports and doesn't
belong cleanly in the core.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:12:01 -08:00
Jakub Kicinski
f05bd8ebeb devlink: move code to a dedicated directory
The devlink code is hard to navigate with 13kLoC in one file.
I really like the way Michal split the ethtool into per-command
files and core. It'd probably be too much to split it all up,
but we can at least separate the core parts out of the per-cmd
implementations and put it in a directory so that new commands
can be separate files.

Move the code, subsequent commit will do a partial split.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-05 22:12:00 -08:00