During eviction, the driver may free more than one hole in the drm_mm
due to the side-effects in evicting the scanned nodes. However,
drm_mm_scan_color_evict() expects that the scan result is the first
available hole (in the mru freed hole_stack list):

  kernel BUG at drivers/gpu/drm/drm_mm.c:844!
  invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
  Dumping ftrace buffer:
     (ftrace buffer empty)
  Modules linked in: i915 snd_hda_codec_analog snd_hda_codec_generic coretemp snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core lpc_ich snd_pcm e1000e mei_me prime_numbers mei
  CPU: 1 PID: 1490 Comm: gem_userptr_bli Tainted: G     U           4.16.0-rc1-g740f57c54ecf-kasan_6+ #1
  Hardware name: Dell Inc. OptiPlex 755                 /0PU052, BIOS A08 02/19/2008
  RIP: 0010:drm_mm_scan_color_evict+0x2b8/0x3d0
  RSP: 0018:ffff880057a573f8 EFLAGS: 00010287
  RAX: ffff8800611f5980 RBX: ffff880057a575d0 RCX: dffffc0000000000
  RDX: 00000000029d5000 RSI: 1ffff1000af4aec1 RDI: ffff8800611f5a10
  RBP: ffff88005ab884d0 R08: ffff880057a57600 R09: 000000000afff000
  R10: 1ffff1000b5710b5 R11: 0000000000001000 R12: 1ffff1000af4ae82
  R13: ffff8800611f59b0 R14: ffff8800611f5980 R15: ffff880057a57608
  FS:  00007f2de0c2e8c0(0000) GS:ffff88006ac40000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f2ddde1e000 CR3: 00000000609b2000 CR4: 00000000000006e0
  Call Trace:
   ? drm_mm_scan_remove_block+0x330/0x330
   ? drm_mm_scan_remove_block+0x151/0x330
   i915_gem_evict_something+0x711/0xbd0 [i915]
   ? igt_evict_contexts+0x50/0x50 [i915]
   ? nop_clear_range+0x10/0x10 [i915]
   ? igt_evict_something+0x90/0x90 [i915]
   ? i915_gem_gtt_reserve+0x1a1/0x320 [i915]
   i915_gem_gtt_insert+0x237/0x400 [i915]
   __i915_vma_do_pin+0xc25/0x1a20 [i915]
   eb_lookup_vmas+0x1c63/0x3790 [i915]
   ? i915_gem_check_execbuffer+0x250/0x250 [i915]
   ? trace_hardirqs_on_caller+0x33f/0x590
   ? _raw_spin_unlock_irqrestore+0x39/0x60
   ? __pm_runtime_resume+0x7d/0xf0
   i915_gem_do_execbuffer+0x86a/0x2ff0 [i915]
   ? __kmalloc+0x132/0x340
   ? i915_gem_execbuffer2_ioctl+0x10f/0x760 [i915]
   ? drm_ioctl_kernel+0x12e/0x1c0
   ? drm_ioctl+0x662/0x980
   ? eb_relocate_slow+0xa90/0xa90 [i915]
   ? i915_gem_execbuffer2_ioctl+0x10f/0x760 [i915]
   ? __might_fault+0xea/0x1a0
   i915_gem_execbuffer2_ioctl+0x3cc/0x760 [i915]
   ? i915_gem_execbuffer_ioctl+0xba0/0xba0 [i915]
   ? lock_acquire+0x3c0/0x3c0
   ? i915_gem_execbuffer_ioctl+0xba0/0xba0 [i915]
   drm_ioctl_kernel+0x12e/0x1c0
   drm_ioctl+0x662/0x980
   ? i915_gem_execbuffer_ioctl+0xba0/0xba0 [i915]
   ? drm_getstats+0x20/0x20
   ? debug_check_no_obj_freed+0x2a6/0x8c0
   do_vfs_ioctl+0x170/0xe70
   ? ioctl_preallocate+0x170/0x170
   ? task_work_run+0xbe/0x160
   ? lock_acquire+0x3c0/0x3c0
   ? trace_hardirqs_on_caller+0x33f/0x590
   ? _raw_spin_unlock_irq+0x2f/0x50
   SyS_ioctl+0x36/0x70
   ? do_vfs_ioctl+0xe70/0xe70
   do_syscall_64+0x18c/0x5d0
   entry_SYSCALL_64_after_hwframe+0x26/0x9b
  RIP: 0033:0x7f2ddf13b587
  RSP: 002b:00007fff15c4f9d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f2ddf13b587
  RDX: 00007fff15c4fa20 RSI: 0000000040406469 RDI: 0000000000000003
  RBP: 00007fff15c4fa20 R08: 0000000000000000 R09: 00007f2ddf3fe120
  R10: 0000000000000073 R11: 0000000000000246 R12: 0000000040406469
  R13: 0000000000000003 R14: 00007fff15c4fa20 R15: 00000000000000c7
  Code: 00 00 00 4a c7 44 22 08 00 00 00 00 42 c7 44 22 10 00 00 00 00 48 81 c4 b8 00 00 00 5b 5d 41 5c 41 5d 41 5e 41 5f c3 0f 0b 0f 0b <0f> 0b 31 c0 eb c0 4c 89 ef e8 9a 09 41 ff e9 1e fe ff ff 4c 89
  RIP: drm_mm_scan_color_evict+0x2b8/0x3d0 RSP: ffff880057a573f8

We can trivially relax this assumption by searching the hole_stack for
the scan result and warn instead if the driver called us without any
result.

Fixes: 3fa489da ("drm: Apply tight eviction scanning to color_adjust")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: <stable@vger.kernel.org> # v4.11+
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180219113543.8010-1-chris@chris-wilson.co.uk

Add a variant of rbtree_replace_node() that maintains the leftmost cache
of struct rbtree_root_cached when replacing nodes within the rbtree.

As drm_mm is the only rb_replace_node() being used on an interval tree,
the mistake looks fairly self-contained.  Furthermore the only user of
drm_mm_replace_node() is its testsuite...

Testcase: igt/drm_mm/replace

Link: http://lkml.kernel.org/r/20171122100729.3742-1-chris@chris-wilson.co.uk
Link: https://patchwork.freedesktop.org/patch/msgid/20171109212435.9265-1-chris@chris-wilson.co.uk
Fixes: f808c13f ("lib/interval_tree: fast overlap detection")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: NDavidlohr Bueso <dbueso@suse.de>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Minor spelling fix for 'monster' and replace 'on' with 'own' in
comments.
Signed-off-by: NLiviu Dudau <Liviu.Dudau@arm.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NGustavo Padovan <gustavo.padovan@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171101140436.2743-1-Liviu.Dudau@arm.com

Allow interval trees to quickly check for overlaps to avoid unnecesary
tree lookups in interval_tree_iter_first().

As of this patch, all interval tree flavors will require using a
'rb_root_cached' such that we can have the leftmost node easily
available.  While most users will make use of this feature, those with
special functions (in addition to the generic insert, delete, search
calls) will avoid using the cached option as they can do funky things
with insertions -- for example, vma_interval_tree_insert_after().

[jglisse@redhat.com: fix deadlock from typo vm_lock_anon_vma()]
  Link: http://lkml.kernel.org/r/20170808225719.20723-1-jglisse@redhat.com
Link: http://lkml.kernel.org/r/20170719014603.19029-12-dave@stgolabs.netSigned-off-by: NDavidlohr Bueso <dbueso@suse.de>
Signed-off-by: NJérôme Glisse <jglisse@redhat.com>
Acked-by: NChristian König <christian.koenig@amd.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NDoug Ledford <dledford@redhat.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Christian Benvenuti <benve@cisco.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As we require valid start/end parameters, we can replace the initial
potential NULL with a pointer to the drm_mm.head_node and so reduce the
test on every iteration from a NULL + address comparison to just an
address comparison.

add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-26 (-26)
function                                     old     new   delta
i915_gem_evict_for_node                      719     693     -26

(No other users outside of the test harness.)
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170204111913.12416-1-chris@chris-wilson.co.uk

The drm_mm range manager claimed to support top-down insertion, but it
was neither searching for the top-most hole that could fit the
allocation request nor fitting the request to the hole correctly.

In order to search the range efficiently, we create a secondary index
for the holes using either their size or their address. This index
allows us to find the smallest hole or the hole at the bottom or top of
the range efficiently, whilst keeping the hole stack to rapidly service
evictions.

v2: Search for holes both high and low. Rename flags to mode.
v3: Discover rb_entry_safe() and use it!
v4: Kerneldoc for enum drm_mm_insert_mode.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Sinclair Yeh <syeh@vmware.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com> # vmwgfx
Reviewed-by: Lucas Stach <l.stach@pengutronix.de> #etnaviv
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170202210438.28702-1-chris@chris-wilson.co.uk

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 ...

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NGustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-5-daniel.vetter@ffwll.ch

Added some boilerplate for the structs, documented members where they
are relevant and plenty of markup for hyperlinks all over. And a few
small wording polish.

Note that the intro needs some more love after the DRM_MM_INSERT_*
patch from Chris has landed.

v2: Spelling fixes (Chris).

v3: Use &struct foo instead of &foo structure (Chris).

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483044517-5770-3-git-send-email-daniel.vetter@ffwll.ch

Including all drivers. I thought about keeping small compat functions
to avoid having to change all drivers. But I really like the
drm_printer idea, so figured spreading it more widely is a good thing.

v2: Review from Chris:
- Natural argument order and better name for drm_mm_print.
- show_mm() macro in the selftest.

Cc: Rob Clark <robdclark@gmail.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jyri Sarha <jsarha@ti.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483009764-8281-1-git-send-email-daniel.vetter@ffwll.ch

A couple of parameters slipped through the kerneldoc net.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161228105120.14500-1-chris@chris-wilson.co.uk

Drivers need to take care. Motivated by a discussion between Mark and
Rob on dri-devel.

Cc: Mark yao <mark.yao@rock-chips.com>
Cc: Rob Clark <robdclark@gmail.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet: s/alloc|freeing/modifications/ per Chris' suggestion.]
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1482833457-29592-1-git-send-email-daniel.vetter@ffwll.ch

Remove a superfluous helper as drm_mm_insert_node is equivalent to
insert_node_in_range with a range of [0, U64_MAX].
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-37-chris@chris-wilson.co.uk

mm->color_adjust() compares the hole with its neighbouring nodes. They
only abutt before we restrict the hole, so we have to apply color_adjust
before we apply the range restriction.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-36-chris@chris-wilson.co.uk

Insulate users from changes to the internal hole tracking within
struct drm_mm_node by using an accessor for hole_follows.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
[danvet: resolve conflicts in i915_vma.c]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Using mm->color_adjust makes the eviction scanner much tricker since we
don't know the actual neighbours of the target hole until after it is
created (after scanning is complete). To work out whether we need to
evict the neighbours because they impact upon the hole, we have to then
check the hole afterwards - requiring an extra step in the user of the
eviction scanner when they apply color_adjust.

v2: Massage kerneldoc.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-34-chris@chris-wilson.co.uk

Since we mandate a strict reverse-order of drm_mm_scan_remove_block()
after drm_mm_scan_add_block() we can further simplify the list
manipulations when generating the temporary scan-hole.

v2: Highlight the games being played with the lists to track the scan
holes without allocation.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-33-chris@chris-wilson.co.uk

For power-of-two alignments, we can avoid the 64bit divide and do a
simple bitwise add instead.

v2: s/alignment_mask/remainder_mask/
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-32-chris@chris-wilson.co.uk

Compute the minimal required hole during scan and only evict those nodes
that overlap. This enables us to reduce the number of nodes we need to
evict to the bare minimum.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-31-chris@chris-wilson.co.uk

The range restriction should be applied after the color adjustment, or
else we may inadvertently apply the color adjustment to the restricted
hole (and not against its neighbours).
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-30-chris@chris-wilson.co.uk

Doing the check is trivial (low cost in comparison to overall eviction)
and helps simplify the code.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-29-chris@chris-wilson.co.uk

Acknowledging that we were building up the hole was more useful to me
when reading the code, than knowing the relationship between this node
and the previous node.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-28-chris@chris-wilson.co.uk

The scan state occupies a large proportion of the struct drm_mm and is
rarely used and only contains temporary state. That makes it suitable to
moving to its struct and onto the stack of the callers.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
[danvet: Fix up etnaviv to compile, was missing a BUG_ON.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

A simple assert to ensure that we don't overflow start + size when
initialising the drm_mm, or its scanner.

In future, we may want to switch to tracking the value of ranges (rather
than size) so that we can cover the full u64, for example like resource
tracking.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-26-chris@chris-wilson.co.uk

Since commit ea7b1dd4 ("drm: mm: track free areas implicitly"),
to test whether there are any nodes allocated within the range manager,
we merely have to ask whether the node_list is empty.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-25-chris@chris-wilson.co.uk

Protect ourselves from a caller passing in node.start + node.size that
will overflow and trick us into reserving that node.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-24-chris@chris-wilson.co.uk

The nodes must be removed in the *reverse* order. This is correct in the
overview, but backwards in the function description. Whilst here add
Intel's copyright statement and tweak some formatting.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-23-chris@chris-wilson.co.uk

In places (e.g. i915.ko), the alignment is exported to userspace as u64
and there now exists hardware for which we can indeed utilize a u64
alignment. As such, we need to keep 64bit integers throughout when
handling alignment.

Testcase: igt/drm_mm/align64
Testcase: igt/gem_exec_alignment
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-22-chris@chris-wilson.co.uk

Use CONFIG_DRM_DEBUG_MM to conditionally enable the internal and
validation checking using BUG_ON. Ideally these paths should all be
exercised by CI selftests (with the asserts enabled).
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-4-chris@chris-wilson.co.uk
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-4-chris@chris-wilson.co.uk

Fairly commonly we want to inspect the node list on the struct drm_mm,
which is buried within an embedded node. Bring it to the surface with a
bit of syntatic sugar.

Note this was intended to be split from commit ad579002 ("drm: Add
drm_mm_for_each_node_safe()") before being applied, but my timing sucks.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-3-chris@chris-wilson.co.uk

Mark up the pointers as constant through the API where appropriate.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161216074718.32500-5-chris@chris-wilson.co.uk

A complement to drm_mm_for_each_node(), wraps list_for_each_entry_safe()
for walking the list of nodes safe against removal.

Note from Joonas:

"Most of the diff is about __drm_mm_nodes(mm), which could be split into
own patch and keep the R-b's."

But I don't feel like insisting on the resend.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
[danvet: Add note.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161216074718.32500-4-chris@chris-wilson.co.uk

commit 202b52b7 ("drm: Track drm_mm nodes with an interval tree")
introduced a requirement that the special drm_mm.head_node was
initialised and marked as not being allocated. It is a very special node
that has no side but has a hole that represents the drm_mm address
space, and holds the list of nodes. Since it is not a real node, it is
not part of the node rbtree and we detect this as it being unallocated.
This presumed that drm_mm_init() was initialising it to zero. It happens
that i915 kzallocs its objects and so it was accidentally setting it,
but for generic use we cannot make that assumption.

[   22.981519] general protection fault: 0000 [#1] SMP
[   22.981521] Modules linked in: test_drm_mm(+) ctr ccm arc4 rt2800usb rt2x00usb rt2800lib rt2x00lib crc_ccitt mac80211 cmac rfcomm bnep snd_hda_codec_realtek snd_hda_codec_hdmi snd_hda_codec_generic snd_hda_intel dcdbas snd_hda_codec x86_pkg_temp_thermal intel_powerclamp btusb snd_hda_core coretemp crct10dif_pclmul cfg80211 btrtl btbcm btintel bluetooth crc32_pclmul ghash_clmulni_intel aesni_intel snd_pcm i2c_hid aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd snd_timer hid_multitouch snd joydev serio_raw lpc_ich mfd_core i2c_designware_platform i2c_designware_core 8250_dw binfmt_misc soundcore acpi_pad nls_iso8859_1 usbhid hid psmouse ahci libahci [last unloaded: test_drm_mm]
[   22.981544] CPU: 1 PID: 2088 Comm: drm_mm Tainted: G        W       4.9.0-rc7+ #234
[   22.981545] Hardware name: Dell Inc. XPS 13 9343/0310JH, BIOS A07 11/11/2015
[   22.981546] task: ffff88020c971cc0 task.stack: ffffc90001728000
[   22.981547] RIP: 0010:[<ffffffff814050f0>]  [<ffffffff814050f0>] drm_mm_interval_tree_add_node+0xa0/0xd0
[   22.981551] RSP: 0018:ffffc9000172ba98  EFLAGS: 00010202
[   22.981552] RAX: 0f0000c69cf63d80 RBX: ffff88020be00000 RCX: ffff88020be00000
[   22.981553] RDX: 0000000000000fff RSI: ffffc9000172bc48 RDI: ffffffff810ac4df
[   22.981553] RBP: ffffc9000172bb08 R08: ffffc9000172bc70 R09: 0000000000000fff
[   22.981554] R10: ffffffff810ac4d7 R11: 4dc04d8b4cffffe5 R12: 0000000000001000
[   22.981555] R13: ffffc9000172bbd0 R14: ffffc9000172bbe0 R15: 0000000002000000
[   22.981556] FS:  00007f80c9fab740(0000) GS:ffff88021f480000(0000) knlGS:0000000000000000
[   22.981557] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   22.981558] CR2: 00007f80c9fd5000 CR3: 000000020c191000 CR4: 00000000003406e0
[   22.981559] Stack:
[   22.981560]  ffffffff81405d09 ffff88020be00000 ffffc9000172bbe0 000000000172bb08
[   22.981562]  ffffffffffffffff 0000000000000000 0000000000000000 0000000000000000
[   22.981563]  0000000002000000 0000000002000000 ffffffffa02f3000 ffff88020be00000
[   22.981565] Call Trace:
[   22.981568]  [<ffffffff81405d09>] ? drm_mm_insert_node_generic+0x229/0x310
[   22.981570]  [<ffffffffa02f3000>] ? 0xffffffffa02f3000
[   22.981572]  [<ffffffffa02903c1>] __subtest_insert_range.constprop.7+0xd1/0x5b0 [test_drm_mm]
[   22.981575]  [<ffffffff81081222>] ? default_wake_function+0x12/0x20
[   22.981576]  [<ffffffff81096905>] ? __wake_up_common+0x55/0x90
[   22.981578]  [<ffffffff81085f42>] ? sched_clock_cpu+0x72/0xa0
[   22.981581]  [<ffffffff811308ad>] ? irq_work_queue+0xd/0x80
[   22.981582]  [<ffffffff810abcc4>] ? wake_up_klogd+0x34/0x40
[   22.981584]  [<ffffffff810ac19d>] ? console_unlock+0x4cd/0x530
[   22.981585]  [<ffffffff810ac4d7>] ? vprintk_emit+0x2d7/0x490
[   22.981587]  [<ffffffff810ac82f>] ? vprintk_default+0x1f/0x30
[   22.981589]  [<ffffffff81146e1c>] ? printk+0x4d/0x4f
[   22.981590]  [<ffffffffa02f3000>] ? 0xffffffffa02f3000
[   22.981592]  [<ffffffffa02908b5>] subtest_insert_range+0x15/0x80 [test_drm_mm]
[   22.981594]  [<ffffffffa02f3088>] test_drm_mm_init+0x88/0x1000 [test_drm_mm]
[   22.981597]  [<ffffffff8100043d>] do_one_initcall+0x3d/0x150
[   22.981600]  [<ffffffff8119dfbf>] ? kfree+0x13f/0x180
[   22.981602]  [<ffffffff811471f2>] do_init_module+0x60/0x1f1
[   22.981606]  [<ffffffff810db878>] load_module+0x2228/0x2790
[   22.981608]  [<ffffffff810d8590>] ? __symbol_put+0x40/0x40
[   22.981612]  [<ffffffff811c52b1>] ? kernel_read+0x41/0x60
[   22.981614]  [<ffffffff810dbfb6>] SYSC_finit_module+0x96/0xd0
[   22.981617]  [<ffffffff810dc00e>] SyS_finit_module+0xe/0x10
[   22.981620]  [<ffffffff816e7aa4>] entry_SYSCALL_64_fastpath+0x17/0x98
[   22.981622] Code: c7 41 30 00 00 00 00 48 89 e5 48 89 3a 48 c7 c2 20 4e 40 81 e8 b2 a1 f0 ff 5d c3 48 8d 56 78 45 31 d2 48 89 d6 eb 25 48 8b 51 58 <48> 39 50 38 73 04 48 89 50 38 4c 8b 58 28 4c 39 59 48 48 8d 50
[   22.981651] RIP  [<ffffffff814050f0>] drm_mm_interval_tree_add_node+0xa0/0xd0
[   22.981655]  RSP <ffffc9000172ba98>

Testcase: igt/drm_mm
Fixes: 202b52b7 ("drm: Track drm_mm nodes with an interval tree")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.9-rc1+
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161130205126.31106-1-chris@chris-wilson.co.uk

Use the color_adjust callback when reserving a node to check if
inserting a node into this hole requires any additional space, and so if
that space then conflicts with an existing allocation.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161123141118.23876-2-chris@chris-wilson.co.uk

Some clients would like to iterate over every node within a certain
range. Make a nice little macro for them to hide the mixing of the
rbtree search and linear walk.

v2: Blurb
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161123141118.23876-1-chris@chris-wilson.co.uk

0day found that stackdepot.h doesn't get automatically included on all
architectures, so remember to add our #include.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Fixes: 5705670d ("drm: Track drm_mm allocators and show leaks on shutdown")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Christian König <christian.koenig@amd.com>.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161108115601.22873-1-chris@chris-wilson.co.uk

We can use the kernel's stack tracer and depot to record the allocation
site of every drm_mm user. Then on shutdown, as well as warning that
allocated nodes still reside with the drm_mm range manager, we can
display who allocated them to aide tracking down the leak.

v2: Move Kconfig around so it lies underneath the DRM options submenu.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161031090806.20073-1-chris@chris-wilson.co.uk

At a higher level, all objects are created with definite size i.e. 0 is
illegal. In forthcoming patches, this assumption is dependent upon in
the drm_mm range manager, i.e. trying to create a drm_mm node with size
0 will have undefined behaviour. Add a couple of WARNs upon creating the
drm_mm node to prevent later bugs.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470248788-30873-1-git-send-email-chris@chris-wilson.co.uk

As we always add this to the drm_mm->hole_stack as our first operation,
we do not need to initialise the list node.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470236651-678-3-git-send-email-chris@chris-wilson.co.uk

In addition to the last-in/first-out stack for accessing drm_mm nodes,
we occasionally and in the future often want to find a drm_mm_node by an
address. To do so efficiently we need to track the nodes in an interval
tree - lookups for a particular address will then be O(lg(N)), where N
is the number of nodes in the range manager as opposed to O(N).
Insertion however gains an extra O(lg(N)) step for all nodes
irrespective of whether the interval tree is in use. For future i915
patches, eliminating the linear walk is a significant improvement.

v2: Use generic interval-tree template for u64 and faster insertion.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470236651-678-1-git-send-email-chris@chris-wilson.co.uk

Do not dereference node before the check if node is NULL.
Signed-off-by: NHeinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: NEric Engestrom <eric.engestrom@imgtec.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1463602639-4861-1-git-send-email-xypron.glpk@gmx.de