We link every DRM "file_priv" to a "drm_master" structure. Currently, the
drmSetMaster() call returns 0 when there is _any_ active master associated
with the "drm_master" structure of the calling "file_priv". This means,
that after drmSetMaster() we are not guaranteed to be DRM-Master and might
not be able to perform mode-setting.

A way to reproduce this is by starting weston with the DRM backend from
within an X-console (eg., xterm). Because the xserver's "drm_master" is
currently active, weston is assigned to the same master but is inactive
because its VT is inactive and the xserver is still active. But when
"fake-activating" weston, it calls drmSetMaster(). With current behavior
this returns "0/success" and weston thinks that it is DRM-Master, even
though it is not (as the xserver is still DRM-Master).
Expected behavior would be drmSetMaster() to return -EINVAL, because the
xserver is still DRM-Master. This patch changes exactly that.

The only way this bogus behavior would be useful is for clients to check
whether their associated "drm_master" is currently the active DRM-Master.
But this logic fails if no DRM-Master is currently active at all. Because
then the client itself would become DRM-Master (if it is root) and this
makes this whole thing useles.

Also note that the second "if-condition":
  file_priv->minor->master != file_priv->master
is always true and can be skipped.
Signed-off-by: NDavid Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Convert #include "..." to #include <path/...> in drivers/gpu/.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NDave Airlie <airlied@redhat.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NDave Jones <davej@redhat.com>

Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The error handling code w.r.t. idr usage looks inconsistent.

In the case of drm_mode_object_get() and drm_ctxbitmap_next() the error
handling is also incomplete.

Unify the code to follow the same pattern always.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

In order to satisfy all the various Kconfig options between
USB and DRM, we need to split the USB code out into a separate module
and export symbols to it.

This fixes build problems in -next reported by sfr.
Signed-off-by: NDave Airlie <airlied@redhat.com>

Two parts to this, one is simple unplug from sysfs for the device node.

The second adds an unplugged state, if we have device opens, we
just set the unplugged state and return, if we have no device
opens we drop the drm device.

If after a lastclose we discover we are unplugged we then
drop the drm device.

v2: use an atomic for unplugged and wrap it for users,
add checks on open + mmap + ioctl entry points.
Signed-off-by: NDave Airlie <airlied@redhat.com>

Reduce drm text size ~1% by using drm_err and
printf extension %pV to emit error messages.

Remove unused macro DRM_MEM_ERROR.

$ size drivers/gpu/drm/built-in.o*
   text	   data	    bss	    dec	    hex	filename
 361159	   9663	    256	 371078	  5a986	drivers/gpu/drm/built-in.o.new
 365416	   9663	    256	 375335	  5ba27	drivers/gpu/drm/built-in.o.old
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This adds an initial framework to plug USB graphics devices
into the drm/kms subsystem.

I've started writing a displaylink driver using this interface.
Signed-off-by: NDave Airlie <airlied@redhat.com>

This abstracts the pci/platform interface out a step further,
we can go further but this is far enough for now to allow USB
to be plugged in.

The drivers now just call the init code directly for their
device type.
Signed-off-by: NDave Airlie <airlied@redhat.com>

The DRI2 swap & sync implementation needs precise
vblank counts and precise timestamps corresponding
to those vblank counts. For conformance to the OpenML
OML_sync_control extension specification the DRM
timestamp associated with a vblank count should
correspond to the start of video scanout of the first
scanline of the video frame following the vblank
interval for that vblank count.

Therefore we need to carry around precise timestamps
for vblanks. Currently the DRM and KMS drivers generate
timestamps ad-hoc via do_gettimeofday() in some
places. The resulting timestamps are sometimes not
very precise due to interrupt handling delays, they
don't conform to OML_sync_control and some are wrong,
as they aren't taken synchronized to the vblank.

This patch implements support inside the drm core
for precise and robust timestamping. It consists
of the following interrelated pieces.

1. Vblank timestamp caching:

A per-crtc ringbuffer stores the most recent vblank
timestamps corresponding to vblank counts.

The ringbuffer can be read out lock-free via the
accessor function:

struct timeval timestamp;
vblankcount = drm_vblank_count_and_time(dev, crtcid, &timestamp).

The function returns the current vblank count and
the corresponding timestamp for start of video
scanout following the vblank interval. It can be
used anywhere between enclosing drm_vblank_get(dev, crtcid)
and drm_vblank_put(dev,crtcid) statements. It is used
inside the drmWaitVblank ioctl and in the vblank event
queueing and handling. It should be used by kms drivers for
timestamping of bufferswap completion.

The timestamp ringbuffer is reinitialized each time
vblank irq's get reenabled in drm_vblank_get()/
drm_update_vblank_count(). It is invalidated when
vblank irq's get disabled.

The ringbuffer is updated inside drm_handle_vblank()
at each vblank irq.

2. Calculation of precise vblank timestamps:

drm_get_last_vbltimestamp() is used to compute the
timestamp for the end of the most recent vblank (if
inside active scanout), or the expected end of the
current vblank interval (if called inside a vblank
interval). The function calls into a new optional kms
driver entry point dev->driver->get_vblank_timestamp()
which is supposed to provide the precise timestamp.
If a kms driver doesn't implement the entry point or
if the call fails, a simple do_gettimeofday() timestamp
is returned as crude approximation of the true vblank time.

A new drm module parameter drm.timestamp_precision_usec
allows to disable high precision timestamps (if set to
zero) or to specify the maximum acceptable error in
the timestamps in microseconds.

Kms drivers could implement their get_vblank_timestamp()
function in a gpu specific way, as long as returned
timestamps conform to OML_sync_control, e.g., by use
of gpu specific hardware timestamps.

Optionally, kms drivers can simply wrap and use the new
utility function drm_calc_vbltimestamp_from_scanoutpos().
This function calls a new optional kms driver function
dev->driver->get_scanout_position() which returns the
current horizontal and vertical video scanout position
of the crtc. The scanout position together with the
drm_display_timing of the current video mode is used
to calculate elapsed time relative to start of active scanout
for the current video frame. This elapsed time is subtracted
from the current do_gettimeofday() time to get the timestamp
corresponding to start of video scanout. Currently
non-interlaced, non-doublescan video modes, with or
without panel scaling are handled correctly. Interlaced/
doublescan modes are tbd in a future patch.

3. Filtering of redundant vblank irq's and removal of
some race-conditions in the vblank irq enable/disable path:

Some gpu's (e.g., Radeon R500/R600) send spurious vblank
irq's outside the vblank if vblank irq's get reenabled.
These get detected by use of the vblank timestamps and
filtered out to avoid miscounting of vblanks.

Some race-conditions between the vblank irq enable/disable
functions, the vblank irq handler and the gpu itself (updating
its hardware vblank counter in the "wrong" moment) are
fixed inside vblank_disable_and_save() and
drm_update_vblank_count() by use of the vblank timestamps and
a new spinlock dev->vblank_time_lock.

The time until vblank irq disable is now configurable via
a new drm module parameter drm.vblankoffdelay to allow
experimentation with timeouts that are much shorter than
the current 5 seconds and should allow longer vblank off
periods for better power savings.

Followup patches will use these new functions to
implement precise timestamping for the intel and radeon
kms drivers.
Signed-off-by: NMario Kleiner <mario.kleiner@tuebingen.mpg.de>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Totally unused.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The information supplied by userspace through these ioctls is only
accessible by dev->drw_idr. But there's no in-tree user of that.
Also userspace does not really care about return values of these ioctls,
either. Only hw/xfree86/dri/dri.c from the xserver actually checks the
return from adddraw and keeps on trying to create a kernel drawable
every time somebody creates a dri drawable. But since that's now a noop,
who cares.

Therefore it's safe to replace these three ioctls with noops and rip
out the implementation.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NKristian Høgsberg <krh@bitplanet.net>
Reviewed-by: NMichel Dänzer <michel@daenzer.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The device name is tightly coupled and created at the same time as the
master->unique address, so we need to free it with the master. Currently
we overwrite it each time we create a new master:

unreferenced object 0xe32c54b0 (size 32):
  comm "Xorg", pid 1455, jiffies 4294721798 (age 3196.879s)
  hex dump (first 32 bytes):
    69 39 31 35 40 70 63 69 3a 30 30 30 30 3a 30 30  i915@pci:0000:00
    3a 30 32 2e 30 00 6b 6b 6b 6b 6b 6b 6b 6b 6b a5  :02.0.kkkkkkkkk.
  backtrace:
    [<c04e5657>] create_object+0x124/0x1f1
    [<c07cf0f0>] kmemleak_alloc+0x4c/0x90
    [<c04db84c>] __kmalloc+0x155/0x175
    [<f8316665>] drm_setversion+0x11d/0x1b1 [drm]
    [<f83148d4>] drm_ioctl+0x29a/0x356 [drm]
    [<c04f27c4>] vfs_ioctl+0x33/0x91
    [<c04f31cf>] do_vfs_ioctl+0x46b/0x496
    [<c04f3240>] sys_ioctl+0x46/0x66
    [<c040325f>] sysenter_do_call+0x12/0x38
    [<ffffffff>] 0xffffffff
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Allow platform devices without PCI resources to be DRM devices.

[airlied: fixup warnings with dev pointers]
Signed-off-by: NJordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Drivers may use vblank calls now (e.g. drm_vblank_off) in their unload
paths, so don't clean up the vblank related structures until after
driver unload.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NKristian Høgsberg <krh@bitplanet.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The vmwgfx driver has a per master rw lock around TTM, to guarantee 
mutual exclusion when needed.

This is typically when all evictable buffers are evicted due to

1) vt switch
2) master switch
3) suspend / resume.

In the multi-master case, on master switch the new master takes the 
previously active master lock in write mode, and then evicts all 
buffers. Any clients to previous masters will then block on that lock 
when trying to validate a buffer. fbdev also acts as a virtual master
wrt this.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NJakob Bornecrantz <jakob@vmware.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This patch adds a new flag to the drmWaitVblank ioctl, which asks the drm
to return immediately and notify userspace when the specified vblank sequence
happens by sending an event back on the drm fd.

The event mechanism works with the other flags supported by the ioctls,
specifically, the vblank sequence can be specified relatively or absolutely,
and works for primary and seconday crtc.

The signal field of the vblank request is used to provide user data,
which will be sent back to user space in the vblank event.
Signed-off-by: NKristian Høgsberg <krh@redhat.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This patch adds a new flag to the drmWaitVblank ioctl, which asks the drm
to return immediately and notify userspace when the specified vblank sequence
happens by sending an event back on the drm fd.

The event mechanism works with the other flags supported by the ioctls,
specifically, the vblank sequence can be specified relatively or absolutely,
and works for primary and seconday crtc.

The signal field of the vblank request is used to provide user data,
which will be sent back to user space in the vblank event.
Signed-off-by: NKristian Høgsberg <krh@redhat.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

If the NULL test is necessary, then the dereference should be moved below
the NULL test.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
type T;
expression E;
identifier i,fld;
statement S;
@@

- T i = E->fld;
+ T i;
  ... when != E
      when != i
  if (E == NULL) S
+ i = E->fld;
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NDave Airlie <airlied@linux.ie>

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: NEric Anholt <eric@anholt.net>

Many developers use "/debug/" or "/debugfs/" or "/sys/kernel/debug/"
directory name to mount debugfs filesystem for ftrace according to
./Documentation/tracers/ftrace.txt file.

And, three directory names(ex:/debug/, /debugfs/, /sys/kernel/debug/) is
existed in kernel source like ftrace, DRM, Wireless, Documentation,
Network[sky2]files to mount debugfs filesystem.

debugfs means debug filesystem for debugging easy to use by greg kroah
hartman. "/sys/kernel/debug/" name is suitable as directory name
of debugfs filesystem.
- debugfs related reference: http://lwn.net/Articles/334546/

Fix inconsistency of directory name to mount debugfs filesystem.

* From Steven Rostedt
  - find_debugfs() and tracing_files() in this patch.
Signed-off-by: NGeunSik Lim <geunsik.lim@samsung.com>
Acked-by     : Inaky Perez-Gonzalez <inaky@linux.intel.com>
Reviewed-by  : Steven Rostedt <rostedt@goodmis.org>
Reviewed-by  : James Smart <james.smart@emulex.com>
CC: Jiri Kosina <trivial@kernel.org>
CC: David Airlie <airlied@linux.ie>
CC: Peter Osterlund <petero2@telia.com>
CC: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
CC: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
CC: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Now all the DRM debug info will be reported if the boot option of
"drm.debug=1" is added. Sometimes it is inconvenient to get the debug
info in KMS mode. We will get too much unrelated info.

This will separate several DRM debug levels and the debug level can be used
to print the different debug info. And the debug level is controlled by the
module parameter of drm.debug

In this patch it is divided into four debug levels;
       	drm_core, drm_driver, drm_kms, drm_mode.

At the same time we can get the different debug info by changing the debug
level. This can be done by adding the module parameter. Of course it can
be changed through the /sys/module/drm/parameters/debug after the system is
booted.

Four debug macro definitions are provided.
	DRM_DEBUG(fmt, args...)
	DRM_DEBUG_DRIVER(prefix, fmt, args...)
	DRM_DEBUG_KMS(prefix, fmt, args...)
	DRM_DEBUG_MODE(prefix, fmt, args...)

When the boot option of "drm.debug=4" is added, it will print the debug info
using DRM_DEBUG_KMS macro definition.
When the boot option of "drm.debug=6" is added, it will print the debug info
using DRM_DEBUG_KMS/DRM_DEBUG_DRIVER.

Sometimes we expect to print the value of an array.
For example: SDVO command,
In such case the following four DRM debug macro definitions are added:
	DRM_LOG(fmt, args...)
	DRM_LOG_DRIVER(fmt, args...)
	DRM_LOG_KMS(fmt, args...)
	DRM_LOG_MODE(fmt, args...)
Signed-off-by: NZhao Yakui <yakui.zhao@intel.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The hash tables contains some of the mapping
so its really nice to have it for the deletion phase.
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

When fast user switching a lot eventually we get to the point,
where we were checking for the wrong thing in this function.
Signed-off-by: NDave Airlie <airlied@redhat.com>

The variable is_master is being used to track the drm_file that is currently
master, so its value needs to be updated accordingly when the master is
changed.
Signed-off-by: NJonas Bonn <jonas@southpole.se>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The old mechanism to formatting proc files is extremely ugly. The
seq_file API was designed specifically for cases like this and greatly
simplifies the process.

Also, most of the files in /proc really don't belong there. This patch
introduces the infrastructure for putting these into debugfs and exposes
all of the proc files in debugfs as well.
Signed-off-by: NBen Gamari <bgamari@gmail.com>
Signed-off-by: NEric Anholt <eric@anholt.net>

The old mechanism to formatting proc files is extremely ugly. The
seq_file API was designed specifically for cases like this and greatly
simplifies the process.

Also, most of the files in /proc really don't belong there. This patch
introduces the infrastructure for putting these into debugfs and exposes
all of the proc files in debugfs as well.

This contains the i915 hooks rewrite as well, to make bisectability better.
Signed-off-by: NBen Gamari <bgamari@gmail.com>
Signed-off-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This is usedul when you have multiple cards to figure out which
one is which minor.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Under kernel modesetting, we manage the device at all times, regardless
of VT switching and X servers, so the only decent thing to do is to
claim the PCI device.  In that case, we call the suspend/resume hooks
directly from the pci driver hooks instead of the current class device detour.
Signed-off-by: NKristian Høgsberg <krh@redhat.com>
Signed-off-by: NDave Airlie <airlied@linux.ie>

[airlied: you shall not retype patches from other trees half asleep]
Signed-of-by: NDave Airlie <airlied@redhat.com>

This is done by
1) Wake up lock waiters when we close the master file descriptor.
   Not when the master structure is removed, since the latter
   requires the waiters themselves to release the refcount on the
   master structure -> Deadlock.
2) Send a SIGTERM to all clients waiting for the lock.
   Normally these clients will get a SIGPIPE when the X server dies,
   but clients may also spin trying to grab the DRM lock, without
   getting any sort of notification.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@linux.ie>

Currently only one waiter is woken up, leaving other waiters
hanging waiting for the DRM lock.
Signed-off-by: NThomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDave Airlie <airlied@linux.ie>

Device maps now contain a link to the master that created them, so
when cleaning up the master, remove any maps that are connected to it.
Also delete any remaining maps at driver unload time.
Signed-off-by: NDave Airlie <airlied@redhat.com>

Add mode setting support to the DRM layer.

This is a fairly big chunk of work that allows DRM drivers to provide
full output control and configuration capabilities to userspace.  It was
motivated by several factors:
  - the fb layer's APIs aren't suited for anything but simple
    configurations
  - coordination between the fb layer, DRM layer, and various userspace
    drivers is poor to non-existent (radeonfb excepted)
  - user level mode setting drivers makes displaying panic & oops
    messages more difficult
  - suspend/resume of graphics state is possible in many more
    configurations with kernel level support

This commit just adds the core DRM part of the mode setting APIs.
Driver specific commits using these new structure and APIs will follow.

Co-authors: Jesse Barnes <jbarnes@virtuousgeek.org>, Jakob Bornecrantz <jakob@tungstengraphics.com>
Contributors: Alan Hourihane <alanh@tungstengraphics.com>, Maarten Maathuis <madman2003@gmail.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Make sure we have the primary node so the device can add maps.
Signed-off-by: NDave Airlie <airlied@redhat.com>

...so drm_getunique() is trying to copy some uninitialized data to
userspace. The ECX register contains the number of words that are
left to copy -- so there are 5 * 4 = 20 bytes left. The offset of the
first uninitialized byte (counting from the start of the string) is
also 20 (i.e. 0xf65d2294&((1 << 5)-1) == 20). So somebody tried to
copy 40 bytes when the string was only 19 long.

In drm_set_busid() we have this code:

        dev->unique_len = 40;
        dev->unique = drm_alloc(dev->unique_len + 1, DRM_MEM_DRIVER);
      ...
        len = snprintf(dev->unique, dev->unique_len, pci:%04x:%02x:%02x.%d",

...so it seems that dev->unique is never updated to reflect the
actual length of the string. The remaining bytes (20 in this case)
are random uninitialized bytes that are copied into userspace.

This patch fixes the problem by setting dev->unique_len after the
snprintf().

airlied- I've had to fix this up to store the alloced size so
we have it for drm_free later.
Reported-by: NSitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: NVegard Nossum <vegardno@thuin.ifi.uio.no>
Signed-off-by: NDave Airlie <airlied@redhat.com>

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: NDave Airlie <airlied@redhat.com>