Don't let a lessee control what the current DRM master is set to;
that's the job of the "real" master. Otherwise, the lessee would
disable all access to master operations for the owner and all lessees
under it.
This matches the same check made in the SET_MASTER ioctl.
Signed-off-by: Keith Packard <keithp@keithp.com>
Fixes: 2ed077e467 ("drm: Add drm_object lease infrastructure [v5]")
Cc: <stable@vger.kernel.org> # v4.15+
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180119015159.1606-1-keithp@keithp.com
Attempts to modify un-leased objects are rejected with an error.
Information returned about unleased objects is modified to make them
appear unusable and/or disconnected.
Changes for v2 as suggested by Daniel Vetter <daniel.vetter@ffwll.ch>:
* With the change in the __drm_mode_object_find API to pass the
file_priv along, we can now centralize most of the lease-based
access checks in that function.
* A few places skip that API and require in-line checks.
Changes for v3 provided by Dave Airlie <airlied@redhat.com>
* remove support for leasing encoders.
* add support for leasing planes.
Changes for v4
* Only call drm_lease_held if DRIVER_MODESET.
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This provides new data structures to hold "lease" information about
drm mode setting objects, and provides for creating new drm_masters
which have access to a subset of the available drm resources.
An 'owner' is a drm_master which is not leasing the objects from
another drm_master, and hence 'owns' them.
A 'lessee' is a drm_master which is leasing objects from some other
drm_master. Each lessee holds the set of objects which it is leasing
from the lessor.
A 'lessor' is a drm_master which is leasing objects to another
drm_master. This is the same as the owner in the current code.
The set of objects any drm_master 'controls' is limited to the set of
objects it leases (for lessees) or all objects (for owners).
Objects not controlled by a drm_master cannot be modified through the
various state manipulating ioctls, and any state reported back to user
space will be edited to make them appear idle and/or unusable. For
instance, connectors always report 'disconnected', while encoders
report no possible crtcs or clones.
The full list of lessees leasing objects from an owner (either
directly, or indirectly through another lessee), can be searched from
an idr in the drm_master of the owner.
Changes for v2 as suggested by Daniel Vetter <daniel.vetter@ffwll.ch>:
* Sub-leasing has been disabled.
* BUG_ON for lock checking replaced with lockdep_assert_held
* 'change' ioctl has been removed.
* Leased objects can always be controlled by the lessor; the
'mask_lease' flag has been removed
* Checking for leased status has been simplified, replacing
the drm_lease_check function with drm_lease_held.
Changes in v3, some suggested by Dave Airlie <airlied@gmail.com>
* Add revocation. This allows leases to be effectively revoked by
removing all of the objects they have access to. The lease itself
hangs around as it's hanging off a file.
* Free the leases IDR when the master is destroyed
* _drm_lease_held should look at lessees, not lessor
* Allow non-master files to check for lease status
Changes in v4, suggested by Dave Airlie <airlied@gmail.com>
* Formatting and whitespace changes
Changes in v5 (airlied)
* check DRIVER_MODESET before lease destroy call
* check DRIVER_MODESET for lease revoke (Chris)
* Use idr_mutex uniformly for all lease elements of struct drm_master. (Keith)
Signed-off-by: Keith Packard <keithp@keithp.com>
I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).
Also some minor drive-by polish where it makes sense, I read a lot
of docs ...
v2: Review from Gustavo.
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-6-daniel.vetter@ffwll.ch
sed -e 's/\( \* .*\)struct &\([_a-z]*\)/\1\&struct \2/' -i
Originally I wasnt a friend of this style because I thought a
line-break between the "&struct" and "foo" part would break it. But a
quick test shows that " * &struct \n * foo\n" works pefectly well with
current kernel-doc. So time to mass-apply these changes!
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483044517-5770-6-git-send-email-daniel.vetter@ffwll.ch
Except for nouveau, only legacy drivers need this really. And nouveau
is already marked up with DRIVER_KMS_LEGACY_CONTEXT as the special
case.
I've tried to be careful to leave everything related to modeset still
using the DRIVER_MODESET flag. Otherwise it's a direct replacement of
!DRIVER_MODESET with DRIVER_LEGACY checks. Also helps readability
since fewer negative checks overall.
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Frank Binns <frank.binns@imgtec.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470251470-30830-2-git-send-email-daniel.vetter@ffwll.ch
Also extract drm_auth.h for nicer grouping.
v2: Nuke the other comments since they don't really explain a lot, and
within the drm core we generally only document functions exported to
drivers: The main audience for these docs are driver writers.
v3: Limit the exposure of drm_master internals by only including
drm_auth.h where it is neede (Chris).
v4: Spelling polish (Emil).
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
- is_master can be removed, we can compute this by checking allowed_master
(which really just tracks whether a master struct has been allocated
for this fpriv in either open or set_master), and whether the fpriv is
the current master on the device.
- that frees up is_master as a good replacement name for allowed_master.
With that it's clear that it tracks whether the fpriv is a master (with
possibly clients attached to it and authenticated against it), and that
one of those fprivs with is_master set is the current master.
v2: Fix kerneldoc for is_master (Emil).
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1466499262-18717-10-git-send-email-daniel.vetter@ffwll.ch
Just rolling out a bit of abstraction to be able to clean
up the master logic in the next step.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
File open/set_maseter ioctl and file close/drop_master ioctl share the
same master handling code. Extract it.
Note that vmwgfx's master_set callback needs to know whether the
master is a new one or has been used already, so thread this through.
On the close/drop side a similar parameter existed, but wasnt used.
Drop it to simplify the flow.
v2: Try to make it not leak so much (Emil).
v3: Send out the right version ...
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466511638-9885-1-git-send-email-daniel.vetter@ffwll.ch
There can only be one current master, and it's for the overall device.
Render/control minors don't support master-based auth at all.
This simplifies the master logic a lot, at least in my eyes: All these
additional pointer chases are just confusing.
While doing the conversion I spotted some locking fail:
- drm_lock/drm_auth check dev->master without holding the
master_mutex. This is fallout from
commit c996fd0b95
Author: Thomas Hellstrom <thellstrom@vmware.com>
Date: Tue Feb 25 19:57:44 2014 +0100
drm: Protect the master management with a drm_device::master_mutex v3
but I honestly don't care one bit about those old legacy drivers
using this.
- debugfs name info should just grab master_mutex.
- And the fbdev helper looked at it to figure out whether someone is
using KMS. We just need a consistent value, so READ_ONCE. Aside: We
should probably check if anyone has opened a control node too, but I
guess current userspace doesn't really do that yet.
v2: Balance locking, reported by Julia.
v3: Rebase on top of Chris' oops fixes.
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v2)
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com> (v2)
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466499262-18717-1-git-send-email-daniel.vetter@ffwll.ch
Simplifies cleanup, and there's no reason drivers should ever care
about authmagic at all - it's all handled in the core.
And with that, Ladies and Gentlemen, it's time to pop the champagen
and celebrate: dev->struct_mutex is now officially gone from modern
drivers, and if a driver is using gem_free_object_unlocked and doesn't
do anything else silly it's positively impossible to ever touch
dev->struct_mutex at runtime, anywhere.
Well except for the mutex_init on driver load ;-)
v2: Rebased.
Cc: Chris Wilson <chris@chris-wilson.co.uk> (v1)
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v1)
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466148814-8194-4-git-send-email-daniel.vetter@ffwll.ch
It's related, and soon authmagic will also use the master_mutex.
There is an ever-so-slightly semantic change here:
- authmagic will only be cleaned up for primary_client drm_minors. But
it's impossible to create authmagic on render/control nodes, so this
is fine.
- The cleanup is moved down a bit in the release processing. Doesn't
matter at all since authmagic is purely internal logic used by the
core ioctl access checks, and when we're in a file's release
callback no one can do ioctls any more.
v2: Rebased.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v1)
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466148814-8194-3-git-send-email-daniel.vetter@ffwll.ch
Another place gone where modern drivers could have hit
dev->struct_mutex.
To avoid too deeply nesting control flow rework it a bit.
v2: Review from Chris:
- remove spurious newline.
- fix file_priv->master like for the !file_priv->is_master case.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466148814-8194-2-git-send-email-daniel.vetter@ffwll.ch
And pull out the primary_client check to make it really obvious that
this can't happen on control/render nodes. Bonus that we can avoid the
master lock in this case.
v2: Don't leak locks on error path (and simplify control flow while
at it), reported by Julia.
Cc: Julia Lawall <julia.lawall@lip6.fr>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1465930269-7883-6-git-send-email-daniel.vetter@ffwll.ch
For modern drivers pretty much the only thing drm_master does is
handling authentication for the primary/legacy drm_minor node. Instead
of having it all over drm files, move it all together into drm_auth.c.
This patch just does code-motion, follow up patches will also extract
the master logic from file open&release paths.
Reviewed-by: Chris Wilson Mchris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1465930269-7883-5-git-send-email-daniel.vetter@ffwll.ch
The magic auth tokens we have are a simple map from cyclic IDs to drm_file
objects. Remove all the old bulk of code and replace it with a simple,
direct IDR.
The previous behavior is kept. Especially calling authmagic multiple times
on the same magic results in EINVAL except on the first call. The only
difference in behavior is that we never allocate IDs multiple times as
long as a client has its FD open.
v2:
- Fix return code of GetMagic()
- Use non-cyclic IDR allocator
- fix off-by-one in "magic > INT_MAX" sanity check
v3:
- drop redundant "magic > INT_MAX" check
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This list is write-only. It's never used for read-access, so no reason to
keep it around. Drop it!
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This way drivers can't grow crazy ideas any more, and it also
helps a bit in reviewing EXPORT_SYMBOLS.
v2: Even more stuff. Unfortunately we can't move drm_vm_open_locked
because exynos does some horrible stuff with it.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
In drm_release(), we currently call drm_remove_magic() if the drm_file
has a drm-magic attached. Therefore, once drm_master_release() is called,
the magic-list _must_ be empty.
By dropping the no-op cleanup, we can move "struct drm_magic_entry" to
drm_auth.c and avoid exposing it to all of DRM.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Convert #include "..." to #include <path/...> in drivers/gpu/.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
If the master tries to authenticate a client using drm_authmagic and
that client has already closed its drm file descriptor,
either wilfully or because it was terminated, the
call to drm_authmagic will dereference a stale pointer into kmalloc'ed memory
and corrupt it.
Typically this results in a hard system hang.
This patch fixes that problem by removing any authentication tokens
(struct drm_magic_entry) open for a file descriptor when that file
descriptor is closed.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
Use kzalloc rather than the combination of kmalloc and memset.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression x,size,flags;
statement S;
@@
-x = kmalloc(size,flags);
+x = kzalloc(size,flags);
if (x == NULL) S
-memset(x, 0, size);
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Reviewed-by: Corbin Simpson <MostAwesomeDude@gmail.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
It hasn't been used in ages, and having the user tell your how much
memory is being freed at free time is a recipe for disaster even if it
was ever used.
Signed-off-by: Eric Anholt <eric@anholt.net>
This is step one towards having multiple masters sharing a drm
device in order to get fast-user-switching to work.
It splits out the information associated with the drm master
into a separate kref counted structure, and allocates this when
a master opens the device node. It also allows the current master
to abdicate (say while VT switched), and a new master to take over
the hardware.
It moves the Intel and radeon drivers to using the sarea from
within the new master structures.
Signed-off-by: Dave Airlie <airlied@redhat.com>
With the coming of kernel based modesetting and the memory manager stuff,
the everything in one directory approach was getting very ugly and
starting to be unmanageable.
This restructures the drm along the lines of other kernel components.
It creates a drivers/gpu/drm directory and moves the hw drivers into
subdirectores. It moves the includes into an include/drm, and
sets up the unifdef for the userspace headers we should be exporting.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Keith Packard