Commit graph

21 commits

Author SHA1 Message Date
Daniel Vetter
3b96a0b140 drm: document drm_auth.c
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>
2016-06-21 22:10:55 +02:00
Daniel Vetter
0aae5920a8 drm: Clear up master tracking booleans
- 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
2016-06-21 21:58:29 +02:00
Daniel Vetter
b3ac9f2591 drm: Extract drm_is_current_master
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>
2016-06-21 21:58:12 +02:00
Daniel Vetter
d6ed682eba drm: Refactor drop/set master code a bit
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
2016-06-21 21:56:28 +02:00
Daniel Vetter
95c081c17f drm: Move master pointer from drm_minor to drm_device
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
2016-06-21 21:43:24 +02:00
Daniel Vetter
d2b34ee62b drm: Protect authmagic with master_mutex
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
2016-06-20 22:02:09 +02:00
Daniel Vetter
a77316bf24 drm: Move authmagic cleanup into drm_master_release
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
2016-06-20 22:02:01 +02:00
Daniel Vetter
0de4cc99c6 drm: Only do the hw.lock cleanup in master_relase for !MODESET
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
2016-06-20 22:01:29 +02:00
Daniel Vetter
14d71ebdb5 drm: Extract drm_master_relase
Like with drm_master_open protect it with a check for primary_client
to make it clear that this can't happen on render/control nodes.

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/1465930269-7883-7-git-send-email-daniel.vetter@ffwll.ch
2016-06-16 10:17:58 +02:00
Daniel Vetter
2cbae7e637 drm: Extract drm_master_open
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
2016-06-16 10:17:42 +02:00
Daniel Vetter
6548f4e7a3 drm: Move master functions into drm_auth.c
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
2016-06-16 10:17:23 +02:00
David Herrmann
32e7b94a3f drm: simplify authentication management
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>
2015-05-05 09:45:57 +02:00
David Herrmann
acab18b5c3 drm: drop unused 'magicfree' list
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>
2015-05-05 09:40:50 +02:00
Daniel Vetter
67d0ec4e88 drm: Move piles of functions from drmP.h to drm_internal.h
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>
2014-09-12 11:16:29 +02:00
David Herrmann
71d39483de drm: move "struct drm_magic_entry" to drm_auth.c
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>
2014-09-10 17:39:50 +10:00
David Howells
760285e7e7 UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/
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>
2012-10-02 18:01:07 +01:00
Thomas Hellstrom
598781d711 drm: Fix authentication kernel crash
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>
2012-01-25 09:27:45 +00:00
Julia Lawall
6ebc22e6d0 drivers/gpu/drm: Use kzalloc
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>
2010-05-18 15:57:05 +10:00
Eric Anholt
9a298b2acd drm: Remove memory debugging infrastructure.
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>
2009-06-18 13:00:33 -07:00
Dave Airlie
7c1c2871a6 drm: move to kref per-master structures.
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>
2008-12-29 17:47:22 +10:00
Dave Airlie
c0e09200dc drm: reorganise drm tree to be more future proof.
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>
2008-07-14 10:45:01 +10:00
Renamed from drivers/char/drm/drm_auth.c (Browse further)