DRM drivers share a common address_space across all character-devices of a
single DRM device. This allows simple buffer eviction and mapping-control.
However, DRM core currently waits for the first ->open() on any char-dev
to mark the underlying inode as backing inode of the device. This delayed
initialization causes ugly conditions all over the place:
  if (dev->dev_mapping)
    do_sth();

To avoid delayed initialization and to stop reusing the inode of the
char-dev, we allocate an anonymous inode for each DRM device and reset
filp->f_mapping to it on ->open().
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

Our current DRM design uses a single address_space for all users of the
same DRM device. However, there is no way to create an anonymous
address_space without an underlying inode. Therefore, we wait for the
first ->open() callback on a registered char-dev and take-over the inode
of the char-dev. This worked well so far, but has several drawbacks:
 - We screw with FS internals and rely on some non-obvious invariants like
   inode->i_mapping being the same as inode->i_data for char-devs.
 - We don't have any address_space prior to the first ->open() from
   user-space. This leads to ugly fallback code and we cannot allocate
   global objects early.

As pointed out by Al-Viro, fs/anon_inode.c is *not* supposed to be used by
drivers for anonymous inode-allocation. Therefore, this patch follows the
proposed alternative solution and adds a pseudo filesystem mount-point to
DRM. We can then allocate private inodes including a private address_space
for each DRM device at initialization time.

Note that we could use:
  sysfs_get_inode(sysfs_mnt->mnt_sb, drm_device->dev->kobj.sd);
to get access to the underlying sysfs-inode of a "struct device" object.
However, most of this information is currently hidden and it's not clear
whether this address_space is suitable for driver access. Thus, unless
linux allows anonymous address_space objects or driver-core provides a
public inode per device, we're left with our own private internal mount
point.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>

Call drm_pci_agp_destroy directly, there's no point in the
indirection. Long term we want to shuffle this into each driver's
unload logic, but that needs cleared-up drm lifetime rules first.

v2: Add a dummy function for !CONFIG_PCI, spotted my David Herrmann.

v3: Fixup for the coding style police.
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Cc: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The PCI bus helper is the only user of it. Call it directly before
device-registration to get rid of the callback.

Note that all drm_agp_*() calls are locked with the drm-global-mutex so we
need to explicitly lock it during initialization. It's not really clear
why it's needed, but lets be safe.

v2: Rebase on top of the agp_init interface change.

v3: Remove the rebase-fail where I've accidentally killed the ->irq_by_busid
callback a bit too early.

Cc: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com> (v1)
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Thanks to the removal of REQUIRE_AGP we can use a void return value
and shed a bit of complexity.
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

There's really no need for the drm core to keep a list of all
devices of a given driver - the linux device model keeps perfect
track of this already for us.

The exception is old legacy ums drivers using pci shadow attaching.
So rename the lists to make the use case clearer and rip out everything
else.

v2: Rebase on top of David Herrmann's drm device register changes.
Also drop the bogus dev_set_drvdata for platform drivers that somehow
crept into the original version - drivers really should be in full
control of that field.

v3: Initialize driver->legacy_dev_list outside of the loop, spotted by
David Herrmann.

v4: Rebase on top of the newly created host1x drm_bus for tegra.

Cc: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Otherwise we risk that the 2nd part of the line ends up on a line of
it's own, which means a kernel dmesg line without a log level. This
then upsets the dmesg checker in piglit.

Only really happens in some of the truly nasty igt testcases which
race cache dropping (through debugfs) with other gem operations.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

All instances of drm_dev_register are followed by drm_dev_free on
failure. Don't free dev->control/render/primary on failure, as they will
be freed by drm_dev_free since commit 8f6599da (drm: delay minor
destruction to drm_dev_free()). Instead unplug them.
Signed-off-by: NIlia Mirkin <imirkin@alum.mit.edu>
Reported-and-tested-by: NBruno Prémont <bonbons@linux-vserver.org>
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

We moved minor deallocation to drm_dev_free() in:
  commit 8f6599da
  Author: David Herrmann <dh.herrmann@gmail.com>
  Date:   Sun Oct 20 18:55:45 2013 +0200

      drm: delay minor destruction to drm_dev_free()

However, this causes a call to drm_unplug_minor(), which should just do
nothing as drm_dev_unregister() already called this.

But a separate patch caused kdev lifetime changes:
  commit 5bdebb18
  Author: Dave Airlie <airlied@redhat.com>
  Date:   Fri Oct 11 14:07:25 2013 +1000

      drm/sysfs: sort out minor and connector device object lifetimes.

Thus making our dev_is_registered() call useles (and even segfault if it
is NULL). Replace it with a simple !kdev test and we're fine.
Reported-by: NHuax Lu <huax.lu@intel.com>
Reported-by: NDaniel Vetter <daniel@ffwll.ch>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=71208Tested-by: Nlu hua <huax.lu@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@gmail.com>

Instead of freeing minors in drm_dev_unregister(), we only unplug them and
delay the free to drm_dev_free(). Note that if drm_dev_register() has
never been called, minors are NULL and this has no effect.

This change is needed to allow early device unregistration. If we want to
call drm_dev_unregister() on live devices, we need to guarantee that
minors are still valid (but unplugged). This way, any open file can still
access file_priv->minor->dev to get the DRM device. However, the minor is
unplugged so no new users can occur.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Don't delay minor removal to drm_put_minor(). Otherwise, user-space can
still open the minor and cause the kernel to oops. Instead, remove the
minor during unplug so any new open() will fail to access this minor.

Note that open() and drm_unplug_minor() are both protected by the global
DRM mutex so we're fine.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

There is no reason to delay debugfs-cleanup to drm_put_minor(). We should
forbid any access to debugfs files once the device is dead. Chances they
oops once a card was unplugged are very high, anyway.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

drm_get_minor() is only used in one file. Make it static and add a
kernel-doc comment which documents the current semantics.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Allow passing NULL as minor to simplify DRM destruction paths. Also remove
the double-pointer reset as it is no longer needed. drm_put_minor() is
only called when the underlying object is destroyed. Hence, resetting
minors to NULL is not necessary.

As drm_put_minor() is no longer used by other DRM files, we can make it
static, too.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This protects drm_unplug_minor() against repeated calls so we can use it
in drm_put_minor(). This allows us to further simplify it in follow-ups as
we no longer do minor-destruction in both functions but only in
drm_unplug_minor().
Also add kernel-doc comments about what these calls do.

[airlied: fixup for changes to kdev stuff]
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The user of these counters was killed in

 commit d79cdc83
 Author: Daniel Vetter <daniel.vetter@ffwll.ch>
 Date:   Thu Aug 8 15:41:32 2013 +0200

    drm: no-op out GET_STATS ioctl

so clean up the leftovers as well.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Analog to drm_dev_register(), we now provide drm_dev_unregister() which
does the reverse. drm_dev_put() is still in place and combines the calls
to drm_dev_unregister() and drm_dev_free() so buses don't have to change.

*_get() and *_put() are used for reference-counting in the kernel.
However, drm_dev_put() definitely does not do any kind of ref-counting.
Hence, use the more appropriate *_register(), *_unregister(), *_alloc()
and *_free() names.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The error paths in DRM bus drivers currently leak memory as they don't
correctly revert drm_dev_alloc(). Introduce drm_dev_free() to free DRM
devices which haven't been registered, yet.

We must be careful not to introduce any side-effects with cleanups done in
drm_dev_free(). drm_ht_remove(), drm_ctxbitmap_cleanup() and
drm_gem_destroy() are all fine in that regard.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

All bus drivers do device setup themselves. This requires us to adjust all
of them if we introduce new core features. Thus, merge all these into a
uniform drm_dev_register() helper.

Note that this removes the drm_lastclose() error path for AGP as it is
horribly broken. Moreover, no bus driver called this in any other error
path either. Instead, we use the recently introduced AGP cleanup helpers.

We also keep a DRIVER_MODESET condition around pci_set_drvdata() to keep
semantics.

[airlied: keep passing flags through so drivers don't oops on load]
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Instead of managing device allocation+initialization in each bus-driver,
we should do that in a central place. drm_fill_in_dev() already does most
of it, but also requires the global drm lock for partial AGP device
registration.

Split both apart so we have a clean device initialization/allocation
phase, and a registration phase.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This reverts commit 7c510133.

Well looks like not enough digging was done, libdrm_nouveau before 2.4.33
used contexts,

292da616fe1f936ca78a3fa8e1b1b19883e343b6 nouveau: pull in major libdrm rewrite

got rid of them,
Reported-by: NPaul Zimmerman <Paul.Zimmerman@synopsys.com>
Reported-by: NMikael Pettersson <mikpe@it.uu.se>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Render nodes provide an API for userspace to use non-privileged GPU
commands without any running DRM-Master. It is useful for offscreen
rendering, GPGPU clients, and normal render clients which do not perform
modesetting.

Compared to legacy clients, render clients no longer need any
authentication to perform client ioctls. Instead, user-space controls
render/client access to GPUs via filesystem access-modes on the
render-node. Once a render-node was opened, a client has full access to
the client/render operations on the GPU. However, no modesetting or ioctls
that affect global state are allowed on render nodes.

To prevent privilege-escalation, drivers must explicitly state that they
support render nodes. They must mark their render-only ioctls as
DRM_RENDER_ALLOW so render clients can use them. Furthermore, they must
support clients without any attached master.

If filesystem access-modes are not enough for fine-grained access control
to render nodes (very unlikely, considering the versaitlity of FS-ACLs),
you may still fall-back to fd-passing from server to client (which allows
arbitrary access-control). However, note that revoking access is
currently impossible and unlikely to get implemented.

Note: Render clients no longer have any associated DRM-Master as they are
supposed to be independent of any server state. DRM core highly depends on
file_priv->master to be non-NULL for modesetting/ctx/etc. commands.
Therefore, drivers must be very careful to not require DRM-Master if they
support DRIVER_RENDER.

So far render-nodes are protected by "drm_rnodes". As long as this
module-parameter is not set to 1, a driver will not create render nodes.
This allows us to experiment with the API a bit before we stabilize it.

v2: drop insecure GEM_FLINK to force use of dmabuf
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

So almost two years ago I've tried to nuke the procfs code already
once before:

http://lists.freedesktop.org/archives/dri-devel/2011-October/015707.html

The conclusion was that userspace drivers (specifically libdrm device
node detection) stopped relying on procfs in 2001. But after some
digging it turned out that the drmstat tool in libdrm is still using
those files (but only when certain options are set). So we've decided
to keep profcs.

But I when I've started to dig around again what exactly this tool
does I've noticed that it tries to read the "mem", "vm", and "vma"
files from procfs. Now as far my git history digging shows "mem" never
did anything useful (at least in the version that first showed up in
upstream history in 2004) and the file was remove in

commit 955b12de
Author: Ben Gamari <bgamari@gmail.com>
Date:   Tue Feb 17 20:08:49 2009 -0500

    drm: Convert proc files to seq_file and introduce debugfs

Which means that for over 4 years drmstat has been broken, and no one
cared. In my opinion that's proof enough that no one is actually using
drmstat, and so that we can savely nuke the procfs support from drm.

While at it fix up the error case cleanup for debugfs in drm_get_minor.

v2: Fix dates, libdrm stopped relying on procfs for drm node detection
in 2001.

v3: fixup compilation warning for !CONFIG_DEBUG_FS, reported by
Fengguang Wu.

Cc: kbuild test robot <fengguang.wu@intel.com>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Currently, both ranges overlap. Fix the limits so both ranges are mutually
exclusive. Also use the occasion to convert whitespaces to tabs.
Signed-off-by: NKristian Høgsberg <krh@bitplanet.net>
(fixed up tabs and adjust commit-msg accordingly)
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

So after a lot of digging around in git histories it looks like this
has only ever be used by dri1 render clients. Hence we can fully
disable the entire thing for modesetting drivers and so greatly reduce
the attack surface for potential exploits (or at least tools like
trinity ...).

Also add the drm_legacy prefix for functions which are called from
common code. To further reduce the impact on common code also extract
all the ctx release handling into a function (instead of only
releasing individual handles) and make ctxbitmap_cleanup return void -
it can never fail.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Introduce two new helpers, drm_agp_clear() and drm_agp_destroy() which
clear all AGP mappings and destroy the AGP head. This allows to reduce the
AGP code in core DRM and move it all to drm_agpsupport.c.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

When dev->driver->master_set() failed ioctl call return 0
but the caller is not the DRM-Master because file_priv->is_master = 0.
Fix that by returning to ioctl caller the driver master_set error code.
Signed-off-by: NBenjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

I'm not sure I understand the intent of the previous behavior.  mmap
on /dev/agpgart and DRM_AGP maps had no cache flags set, so they
would be fully cacheable.  But the DRM code (most of the time) would
add a write-combining MTRR that would change the effective memory
type to WC.

The new behavior just requests WC explicitly for all AGP maps.

If there is any code out there that expects cacheable access to the
AGP aperture (because the drm driver doesn't request an MTRR or
because it's using /dev/agpgart directly), then it will now end up
with a UC or WC mapping, depending on the architecture and PAT
availability.  But cacheable access to the aperture seems like it's
asking for trouble, because, AIUI, the aperture is an alias of RAM.
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Use minor->index to label things, not the name field from the proc_dir_entry
of the /proc/dwm/<minor>/ directory.

Also, use "%u" not "%d" to render the value and use a 12-byte buffer in which
to render the integer, not a 16-byte buffer.  The longest string an unsigned
int can give you is 10 chars (4294967295) plus a NUL, so round up to 12 as the
stack is likely to be 4- or 8-byte aligned.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
cc: dri-devel@lists.freedesktop.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Convert to the much saner new idr interface.

* drm_ctxbitmap_next() error handling in drm_addctx() seems broken.
  drm_ctxbitmap_next() return -errno on failure not -1.

[artem.savkov@gmail.com: missing idr_preload_end in drm_gem_flink_ioctl]
[jslaby@suse.cz: fix drm_gem_flink_ioctl() return value]
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NDavid Airlie <airlied@linux.ie>
Signed-off-by: NArtem Savkov <artem.savkov@gmail.com>
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Jumps in the vblank and page flip event timestamps cause trouble for
clients, so we should avoid them. The timestamp we get currently with
gettimeofday can jump, so use instead monotonic timestamps.

For backward compatibility use a module flag to revert back to using
gettimeofday timestamps. Add also a DRM_CAP_TIMESTAMP_MONOTONIC flag
that is simply a read only version of the module flag, so that clients
can query this without depending on sysfs.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

kfree on a null argument is a no-op.
Silences the following smatch warning:
drivers/gpu/drm/drm_stub.c:496 drm_put_dev() info:
redundant null check on dev->devname calling kfree()
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

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>