drm/i915: Retry gtt fault when out of fence registers

If we can't find a free fence register to handle a fault in the GMADR
range just return VM_FAULT_NOPAGE without populating the PTE so that
userspace will retry the access and trigger another fault. Eventually
we should find a free fence and the fault will get properly handled.

A further improvement idea might be to reserve a fence (or one per CPU?)
for the express purpose of handling faults without having to retry. But
that would require some additional work.

Looks like this may have gotten broken originally by
commit 39965b376601 ("drm/i915: don't trash the gtt when running out of fences")
as that changed the errno to -EDEADLK which wasn't handle by the gtt
fault code either. But later in commit 2feeb52859fc ("drm/i915/gt: Fix
-EDEADLK handling regression") I changed it again to -ENOBUFS as -EDEADLK
was now getting used for the ww mutex dance. So this fix only makes
sense after that last commit.

Cc: stable@vger.kernel.org
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9479
Fixes: 2feeb52859fc ("drm/i915/gt: Fix -EDEADLK handling regression")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231012132801.16292-1-ville.syrjala@linux.intel.com
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>

file, i915: fix file reference for mmap_singleton()

Today we got a report at [1] for rcu stalls on the i915 testsuite in [2]
due to the conversion of files to SLAB_TYPSSAFE_BY_RCU. Afaict,
get_file_rcu() goes into an infinite loop trying to carefully verify
that i915->gem.mmap_singleton hasn't changed - see the splat below.

So I stared at this code to figure out what it actually does. It seems
that the i915->gem.mmap_singleton pointer itself never had rcu semantics.

The i915->gem.mmap_singleton is replaced in
file->f_op->release::singleton_release():

static int singleton_release(struct inode *inode, struct file *file)
{
struct drm_i915_private *i915 = file->private_data;

cmpxchg(&i915->gem.mmap_singleton, file, NULL);
drm_dev_put(&i915->drm);

return 0;
}

The cmpxchg() is ordered against a concurrent update of
i915->gem.mmap_singleton from mmap_singleton(). IOW, when
mmap_singleton() fails to get a reference on i915->gem.mmap_singleton:

While mmap_singleton() does

rcu_read_lock();
file = get_file_rcu(&i915->gem.mmap_singleton);
rcu_read_unlock();

it allocates a new file via anon_inode_getfile() and does

smp_store_mb(i915->gem.mmap_singleton, file);

So, then what happens in the case of this bug is that at some point
fput() is called and drops the file->f_count to zero leaving the pointer
in i915->gem.mmap_singleton in tact.

Now, there might be delays until
file->f_op->release::singleton_release() is called and
i915->gem.mmap_singleton is set to NULL.

Say concurrently another task hits mmap_singleton() and does:

rcu_read_lock();
file = get_file_rcu(&i915->gem.mmap_singleton);
rcu_read_unlock();

When get_file_rcu() fails to get a reference via atomic_inc_not_zero()
it will try the reload from i915->gem.mmap_singleton expecting it to be
NULL, assuming it has comparable semantics as we expect in
__fget_files_rcu().

But it hasn't so it reloads the same pointer again, trying the same
atomic_inc_not_zero() again and doing so until
file->f_op->release::singleton_release() of the old file has been
called.

So, in contrast to __fget_files_rcu() here we want to not retry when
atomic_inc_not_zero() has failed. We only want to retry in case we
managed to get a reference but the pointer did change on reload.

<3> [511.395679] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
<3> [511.395716] rcu: Tasks blocked on level-1 rcu_node (CPUs 0-9): P6238
<3> [511.395934] rcu: (detected by 16, t=65002 jiffies, g=123977, q=439 ncpus=20)
<6> [511.395944] task:i915_selftest state:R running task stack:10568 pid:6238 tgid:6238 ppid:1001 flags:0x00004002
<6> [511.395962] Call Trace:
<6> [511.395966] <TASK>
<6> [511.395974] ? __schedule+0x3a8/0xd70
<6> [511.395995] ? asm_sysvec_apic_timer_interrupt+0x1a/0x20
<6> [511.396003] ? lockdep_hardirqs_on+0xc3/0x140
<6> [511.396013] ? asm_sysvec_apic_timer_interrupt+0x1a/0x20
<6> [511.396029] ? get_file_rcu+0x10/0x30
<6> [511.396039] ? get_file_rcu+0x10/0x30
<6> [511.396046] ? i915_gem_object_mmap+0xbc/0x450 [i915]
<6> [511.396509] ? i915_gem_mmap+0x272/0x480 [i915]
<6> [511.396903] ? mmap_region+0x253/0xb60
<6> [511.396925] ? do_mmap+0x334/0x5c0
<6> [511.396939] ? vm_mmap_pgoff+0x9f/0x1c0
<6> [511.396949] ? rcu_is_watching+0x11/0x50
<6> [511.396962] ? igt_mmap_offset+0xfc/0x110 [i915]
<6> [511.397376] ? __igt_mmap+0xb3/0x570 [i915]
<6> [511.397762] ? igt_mmap+0x11e/0x150 [i915]
<6> [511.398139] ? __trace_bprintk+0x76/0x90
<6> [511.398156] ? __i915_subtests+0xbf/0x240 [i915]
<6> [511.398586] ? __pfx___i915_live_setup+0x10/0x10 [i915]
<6> [511.399001] ? __pfx___i915_live_teardown+0x10/0x10 [i915]
<6> [511.399433] ? __run_selftests+0xbc/0x1a0 [i915]
<6> [511.399875] ? i915_live_selftests+0x4b/0x90 [i915]
<6> [511.400308] ? i915_pci_probe+0x106/0x200 [i915]
<6> [511.400692] ? pci_device_probe+0x95/0x120
<6> [511.400704] ? really_probe+0x164/0x3c0
<6> [511.400715] ? __pfx___driver_attach+0x10/0x10
<6> [511.400722] ? __driver_probe_device+0x73/0x160
<6> [511.400731] ? driver_probe_device+0x19/0xa0
<6> [511.400741] ? __driver_attach+0xb6/0x180
<6> [511.400749] ? __pfx___driver_attach+0x10/0x10
<6> [511.400756] ? bus_for_each_dev+0x77/0xd0
<6> [511.400770] ? bus_add_driver+0x114/0x210
<6> [511.400781] ? driver_register+0x5b/0x110
<6> [511.400791] ? i915_init+0x23/0xc0 [i915]
<6> [511.401153] ? __pfx_i915_init+0x10/0x10 [i915]
<6> [511.401503] ? do_one_initcall+0x57/0x270
<6> [511.401515] ? rcu_is_watching+0x11/0x50
<6> [511.401521] ? kmalloc_trace+0xa3/0xb0
<6> [511.401532] ? do_init_module+0x5f/0x210
<6> [511.401544] ? load_module+0x1d00/0x1f60
<6> [511.401581] ? init_module_from_file+0x86/0xd0
<6> [511.401590] ? init_module_from_file+0x86/0xd0
<6> [511.401613] ? idempotent_init_module+0x17c/0x230
<6> [511.401639] ? __x64_sys_finit_module+0x56/0xb0
<6> [511.401650] ? do_syscall_64+0x3c/0x90
<6> [511.401659] ? entry_SYSCALL_64_after_hwframe+0x6e/0xd8
<6> [511.401684] </TASK>

Link: [1]: https://lore.kernel.org/intel-gfx/SJ1PR11MB6129CB39EED831784C331BAFB9DEA@SJ1PR11MB6129.namprd11.prod.outlook.com
Link: [2]: https://intel-gfx-ci.01.org/tree/linux-next/next-20231013/bat-dg2-11/igt@i915_selftest@live@mman.html#dmesg-warnings10963
Cc: Jann Horn <jannh@google.com>,
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20231025-formfrage-watscheln-84526cd3bd7d@brauner
Signed-off-by: Christian Brauner <brauner@kernel.org>

file: convert to SLAB_TYPESAFE_BY_RCU

In recent discussions around some performance improvements in the file
handling area we discussed switching the file cache to rely on
SLAB_TYPESAFE_BY_RCU which allows us to get rid of call_rcu() based
freeing for files completely. This is a pretty sensitive change overall
but it might actually be worth doing.

The main downside is the subtlety. The other one is that we should
really wait for Jann's patch to land that enables KASAN to handle
SLAB_TYPESAFE_BY_RCU UAFs. Currently it doesn't but a patch for this
exists.

With SLAB_TYPESAFE_BY_RCU objects may be freed and reused multiple times
which requires a few changes. So it isn't sufficient anymore to just
acquire a reference to the file in question under rcu using
atomic_long_inc_not_zero() since the file might have already been
recycled and someone else might have bumped the reference.

In other words, callers might see reference count bumps from newer
users. For this reason it is necessary to verify that the pointer is the
same before and after the reference count increment. This pattern can be
seen in get_file_rcu() and __files_get_rcu().

In addition, it isn't possible to access or check fields in struct file
without first aqcuiring a reference on it. Not doing that was always
very dodgy and it was only usable for non-pointer data in struct file.
With SLAB_TYPESAFE_BY_RCU it is necessary that callers first acquire a
reference under rcu or they must hold the files_lock of the fdtable.
Failing to do either one of this is a bug.

Thanks to Jann for pointing out that we need to ensure memory ordering
between reallocations and pointer check by ensuring that all subsequent
loads have a dependency on the second load in get_file_rcu() and
providing a fixup that was folded into this patch.

Cc: Jann Horn <jannh@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

drm/i915: Retry gtt fault when out of fence registers

If we can't find a free fence register to handle a fault in the GMADR
range just return VM_FAULT_NOPAGE without populating the PTE so that
userspace will retry the access and trigger another fault. Eventually
we should find a free fence and the fault will get properly handled.

A further improvement idea might be to reserve a fence (or one per CPU?)
for the express purpose of handling faults without having to retry. But
that would require some additional work.

Looks like this may have gotten broken originally by
commit 39965b376601 ("drm/i915: don't trash the gtt when running out of fences")
as that changed the errno to -EDEADLK which wasn't handle by the gtt
fault code either. But later in commit 2feeb52859fc ("drm/i915/gt: Fix
-EDEADLK handling regression") I changed it again to -ENOBUFS as -EDEADLK
was now getting used for the ww mutex dance. So this fix only makes
sense after that last commit.

Cc: stable@vger.kernel.org
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9479
Fixes: 2feeb52859fc ("drm/i915/gt: Fix -EDEADLK handling regression")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231012132801.16292-1-ville.syrjala@linux.intel.com
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
(cherry picked from commit 7f403caabe811b88ab0de3811ff3f4782c415761)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915: Fix a NULL vs IS_ERR() bug

The mmap_offset_attach() function returns error pointers, it doesn't
return NULL.

Fixes: eaee1c085863 ("drm/i915: Add a function to mmap framebuffer obj")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ZH7tHLRZ9oBjedjN@moroto

drm/i915: Fix a NULL vs IS_ERR() bug

The mmap_offset_attach() function returns error pointers, it doesn't
return NULL.

Fixes: eaee1c085863 ("drm/i915: Add a function to mmap framebuffer obj")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ZH7tHLRZ9oBjedjN@moroto
(cherry picked from commit 3a89311387cde27da8e290458b2d037133c1f7b5)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

drm/i915: use pat_index instead of cache_level

Currently the KMD is using enum i915_cache_level to set caching policy for
buffer objects. This is flaky because the PAT index which really controls
the caching behavior in PTE has far more levels than what's defined in the
enum. In addition, the PAT index is platform dependent, having to translate
between i915_cache_level and PAT index is not reliable, and makes the code
more complicated.

From UMD's perspective there is also a necessity to set caching policy for
performance fine tuning. It's much easier for the UMD to directly use PAT
index because the behavior of each PAT index is clearly defined in Bspec.
Having the abstracted i915_cache_level sitting in between would only cause
more ambiguity. PAT is expected to work much like MOCS already works today,
and by design userspace is expected to select the index that exactly
matches the desired behavior described in the hardware specification.

For these reasons this patch replaces i915_cache_level with PAT index. Also
note, the cache_level is not completely removed yet, because the KMD still
has the need of creating buffer objects with simple cache settings such as
cached, uncached, or writethrough. For kernel objects, cache_level is used
for simplicity and backward compatibility. For Pre-gen12 platforms PAT can
have 1:1 mapping to i915_cache_level, so these two are interchangeable. see
the use of LEGACY_CACHELEVEL.

One consequence of this change is that gen8_pte_encode is no longer working
for gen12 platforms due to the fact that gen12 platforms has different PAT
definitions. In the meantime the mtl_pte_encode introduced specfically for
MTL becomes generic for all gen12 platforms. This patch renames the MTL
PTE encode function into gen12_pte_encode and apply it to all gen12. Even
though this change looks unrelated, but separating them would temporarily
break gen12 PTE encoding, thus squash them in one patch.

Special note: this patch changes the way caching behavior is controlled in
the sense that some objects are left to be managed by userspace. For such
objects we need to be careful not to change the userspace settings.There
are kerneldoc and comments added around obj->cache_coherent, cache_dirty,
and how to bypass the checkings by i915_gem_object_has_cache_level. For
full understanding, these changes need to be looked at together with the
two follow-up patches, one disables the {set|get}_caching ioctl's and the
other adds set_pat extension to the GEM_CREATE uAPI.

Bspec: 63019

Cc: Chris Wilson <chris.p.wilson@linux.intel.com>
Signed-off-by: Fei Yang <fei.yang@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230509165200.1740-3-fei.yang@intel.com

drm/i915: Add a function to mmap framebuffer obj

Implement i915_gem_fb_mmap() to enable fb_ops.fb_mmap()
callback for i915's framebuffer objects.

v2: add a comment why i915_gem_object_get() needed(Andi).
v3: mmap also ttm objects.

Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Andi Shyti <andi.shyti@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230404143100.10452-3-nirmoy.das@intel.com

mm: replace vma->vm_flags direct modifications with modifier calls

Replace direct modifications to vma->vm_flags with calls to modifier
functions to be able to track flag changes and to keep vma locking
correctness.

[akpm@linux-foundation.org: fix drivers/misc/open-dice.c, per Hyeonggon Yoo]
Link: https://lkml.kernel.org/r/20230126193752.297968-5-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjun Roy <arjunroy@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Minchan Kim <minchan@google.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Oskolkov <posk@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Punit Agrawal <punit.agrawal@bytedance.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

drm/i915: improve the catch-all evict to handle lock contention

The catch-all evict can fail due to object lock contention, since it
only goes as far as trylocking the object, due to us already holding the
vm->mutex. Doing a full object lock here can deadlock, since the
vm->mutex is always our inner lock. Add another execbuf pass which drops
the vm->mutex and then tries to grab the object will the full lock,
before then retrying the eviction. This should be good enough for now to
fix the immediate regression with userspace seeing -ENOSPC from execbuf
due to contended object locks during GTT eviction.

v2 (Mani)
- Also revamp the docs for the different passes.

Testcase: igt@gem_ppgtt@shrink-vs-evict-*
Fixes: 7e00897be8bf ("drm/i915: Add object locking to i915_gem_evict_for_node and i915_gem_evict_something, v2.")
References: https://gitlab.freedesktop.org/drm/intel/-/issues/7627
References: https://gitlab.freedesktop.org/drm/intel/-/issues/7570
References: https://bugzilla.mozilla.org/show_bug.cgi?id=1779558
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Mani Milani <mani@chromium.org>
Cc: <stable@vger.kernel.org> # v5.18+
Reviewed-by: Mani Milani <mani@chromium.org>
Tested-by: Mani Milani <mani@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221216113456.414183-1-matthew.auld@intel.com

drm/i915: Wrap all access to i915_vma.node.start|size

We already wrap i915_vma.node.start for use with the GGTT, as there we
can perform additional sanity checks that the node belongs to the GGTT
and fits within the 32b registers. In the next couple of patches, we
will introduce guard pages around the objects _inside_ the drm_mm_node
allocation. That is we will offset the vma->pages so that the first page
is at drm_mm_node.start + vma->guard (not 0 as is currently the case).
All users must then not use i915_vma.node.start directly, but compute
the guard offset, thus all users are converted to use a
i915_vma_offset() wrapper.

The notable exceptions are the selftests that are testing exact
behaviour of i915_vma_pin/i915_vma_insert.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Tejas Upadhyay <tejaskumarx.surendrakumar.upadhyay@intel.com>
Co-developed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221130235805.221010-3-andi.shyti@linux.intel.com

drm/i915: Fix a memory leak with reused mmap_offset

drm_vma_node_allow() and drm_vma_node_revoke() should be called in
balanced pairs. We call drm_vma_node_allow() once per-file everytime a
user calls mmap_offset, but only call drm_vma_node_revoke once per-file
on each mmap_offset. As the mmap_offset is reused by the client, the
per-file vm_count may remain non-zero and the rbtree leaked.

Call drm_vma_node_allow_once() instead to prevent that memory leak.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Andi Shyti <andi.shyti@linux.intel.com>

Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Fixes: 786555987207 ("drm/i915/gem: Store mmap_offsets in an rbtree rather than a plain list")
Reported-by: Chuansheng Liu <chuansheng.liu@intel.com>
Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://lore.kernel.org/r/20230117175236.22317-2-nirmoy.das@intel.com
Signed-off-by: Maxime Ripard <maxime@cerno.tech>

drm/i915: improve the catch-all evict to handle lock contention

The catch-all evict can fail due to object lock contention, since it
only goes as far as trylocking the object, due to us already holding the
vm->mutex. Doing a full object lock here can deadlock, since the
vm->mutex is always our inner lock. Add another execbuf pass which drops
the vm->mutex and then tries to grab the object will the full lock,
before then retrying the eviction. This should be good enough for now to
fix the immediate regression with userspace seeing -ENOSPC from execbuf
due to contended object locks during GTT eviction.

v2 (Mani)
- Also revamp the docs for the different passes.

Testcase: igt@gem_ppgtt@shrink-vs-evict-*
Fixes: 7e00897be8bf ("drm/i915: Add object locking to i915_gem_evict_for_node and i915_gem_evict_something, v2.")
References: https://gitlab.freedesktop.org/drm/intel/-/issues/7627
References: https://gitlab.freedesktop.org/drm/intel/-/issues/7570
References: https://bugzilla.mozilla.org/show_bug.cgi?id=1779558
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Mani Milani <mani@chromium.org>
Cc: <stable@vger.kernel.org> # v5.18+
Reviewed-by: Mani Milani <mani@chromium.org>
Tested-by: Mani Milani <mani@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221216113456.414183-1-matthew.auld@intel.com
(cherry picked from commit 801fa7a81f6da533cc5442fc40e32c72b76cd42a)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915/guc: Don't deadlock busyness stats vs reset

The engine busyness stats has a worker function to do things like
64bit extend the 32bit hardware counters. The GuC's reset prepare
function flushes out this worker function to ensure no corruption
happens during the reset. Unforunately, the worker function has an
infinite wait for active resets to finish before doing its work. Thus
a deadlock would occur if the worker function had actually started
just as the reset starts.

The function being used to lock the reset-in-progress mutex is called
intel_gt_reset_trylock(). However, as noted it does not follow
standard 'trylock' conventions and exit if already locked. So rename
the current _trylock function to intel_gt_reset_lock_interruptible(),
which is the behaviour it actually provides. In addition, add a new
implementation of _trylock and call that from the busyness stats
worker instead.

v2: Rename existing trylock to interruptible rather than trying to
preserve the existing (confusing) naming scheme (review comments from
Tvrtko).

Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221102192109.2492625-3-John.C.Harrison@Intel.com

drm/i915/dgfx: Grab wakeref at i915_ttm_unmap_virtual

We had already grabbed the rpm wakeref at obj destruction path,
but it also required to grab the wakeref when object moves.
When i915_gem_object_release_mmap_offset() gets called by
i915_ttm_move_notify(), it will release the mmap offset without
grabbing the wakeref. We want to avoid that therefore,
grab the wakeref at i915_ttm_unmap_virtual() accordingly.

While doing that also changed the lmem_userfault_lock from
mutex to spinlock, as spinlock widely used for list.

Also changed if (obj->userfault_count) to
GEM_BUG_ON(!obj->userfault_count).

v2:
- Removed lmem_userfault_{list,lock} from intel_gt. [Matt Auld]

Fixes: ad74457a6b5a ("drm/i915/dgfx: Release mmap on rpm suspend")
Suggested-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221027092242.1476080-3-anshuman.gupta@intel.com

drm/i915: Encapsulate lmem rpm stuff in intel_runtime_pm

Runtime pm is not really per GT, therefore it make sense to
move lmem_userfault_list, lmem_userfault_lock and
userfault_wakeref from intel_gt to intel_runtime_pm structure,
which is embedded to i915.

No functional change.

v2:
- Fixes the code comment nit. [Matt Auld]

Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221027092242.1476080-2-anshuman.gupta@intel.com

drm/i915/dgfx: Release mmap on rpm suspend

Release all mmap mapping for all lmem objects which are associated
with userfault such that, while pcie function in D3hot, any access
to memory mappings will raise a userfault.

Runtime resume the dgpu(when gem object lies in lmem).
This will transition the dgpu graphics function to D0
state if it was in D3 in order to access the mmap memory
mappings.

v2:
- Squashes the patches. [Matt Auld]
- Add adequate locking for lmem_userfault_list addition. [Matt Auld]
- Reused obj->userfault_count to avoid double addition. [Matt Auld]
- Added i915_gem_object_lock to check
i915_gem_object_is_lmem. [Matt Auld]

v3:
- Use i915_ttm_cpu_maps_iomem. [Matt Auld]
- Fix 'ret == 0 to ret == VM_FAULT_NOPAGE'. [Matt Auld]
- Reuse obj->userfault_count as a bool 0 or 1. [Matt Auld]
- Delete the mmaped obj from lmem_userfault_list in obj
destruction path. [Matt Auld]
- Get a wakeref for object destruction patch. [Matt Auld]
- Use intel_wakeref_auto to delay runtime PM. [Matt Auld]

v4:
- Avoid using mmo offset to get the vma_node. [Matt Auld]
- Added comment to use the lmem_userfault_lock. [Matt Auld]
- Get lmem_userfault_lock in i915_gem_object_release_mmap_offset.
[Matt Auld]
- Fixed kernel test robot generated warning.

v5:
- Addressed the cosmetics comments. [Andi]
- Changed i915_gem_runtime_pm_object_release_mmap_offset() name to
i915_gem_object_runtime_pm_release_mmap_offset() to be rhythmic.

PCIe Specs 5.3.1.4.1

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6331
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220913152714.16541-3-anshuman.gupta@intel.com

drm/i915: Refactor userfault_wakeref to re-use

Refactor userfault_wakeref to re-use for discrete lmem mmap mapping
as well, as on discrete GTT mmap are not supported. Moving
userfault_wakeref from ggtt to gt structure.

Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220913152714.16541-2-anshuman.gupta@intel.com

drm/i915: Rename ggtt_view as gtt_view

So far, different views (normal, partial, rotated and remapped)
into the same object are only supported for GGTT mappings.
But with the upcoming VM_BIND feature, PPGTT will also use the
partial view mapping. Hence rename ggtt_view to more generic
gtt_view.

Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220901183854.3446-1-niranjana.vishwanathapura@intel.com

drm/i915: Sunset igpu legacy mmap support based on GRAPHICS_VER_FULL

The intent of the version check in the mmap ioctl was to maintain
support for existing platforms (i.e., ADL/RPL and earlier), but drop
support on all future igpu platforms. As we've seen on the dgpu side,
the hardware teams are using a more fine-grained numbering system for IP
version numbers these days, so it's possible the version number
associated with our next igpu could be some form of "12.xx" rather than
13 or higher. Comparing against the full ver.release number will ensure
the intent of the check is maintained no matter what numbering the
hardware teams settle on.

Fixes: d3f3baa3562a ("drm/i915: Reinstate the mmap ioctl for some platforms")
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220407161839.1073443-1-matthew.d.roper@intel.com

drm/i915/gem: add missing boundary check in vm_access

A missing bounds check in vm_access() can lead to an out-of-bounds read
or write in the adjacent memory area, since the len attribute is not
validated before the memcpy later in the function, potentially hitting:

[ 183.637831] BUG: unable to handle page fault for address: ffffc90000c86000
[ 183.637934] #PF: supervisor read access in kernel mode
[ 183.637997] #PF: error_code(0x0000) - not-present page
[ 183.638059] PGD 100000067 P4D 100000067 PUD 100258067 PMD 106341067 PTE 0
[ 183.638144] Oops: 0000 [#2] PREEMPT SMP NOPTI
[ 183.638201] CPU: 3 PID: 1790 Comm: poc Tainted: G D 5.17.0-rc6-ci-drm-11296+ #1
[ 183.638298] Hardware name: Intel Corporation CoffeeLake Client Platform/CoffeeLake H DDR4 RVP, BIOS CNLSFWR1.R00.X208.B00.1905301319 05/30/2019
[ 183.638430] RIP: 0010:memcpy_erms+0x6/0x10
[ 183.640213] RSP: 0018:ffffc90001763d48 EFLAGS: 00010246
[ 183.641117] RAX: ffff888109c14000 RBX: ffff888111bece40 RCX: 0000000000000ffc
[ 183.642029] RDX: 0000000000001000 RSI: ffffc90000c86000 RDI: ffff888109c14004
[ 183.642946] RBP: 0000000000000ffc R08: 800000000000016b R09: 0000000000000000
[ 183.643848] R10: ffffc90000c85000 R11: 0000000000000048 R12: 0000000000001000
[ 183.644742] R13: ffff888111bed190 R14: ffff888109c14000 R15: 0000000000001000
[ 183.645653] FS: 00007fe5ef807540(0000) GS:ffff88845b380000(0000) knlGS:0000000000000000
[ 183.646570] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 183.647481] CR2: ffffc90000c86000 CR3: 000000010ff02006 CR4: 00000000003706e0
[ 183.648384] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 183.649271] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 183.650142] Call Trace:
[ 183.650988] <TASK>
[ 183.651793] vm_access+0x1f0/0x2a0 [i915]
[ 183.652726] __access_remote_vm+0x224/0x380
[ 183.653561] mem_rw.isra.0+0xf9/0x190
[ 183.654402] vfs_read+0x9d/0x1b0
[ 183.655238] ksys_read+0x63/0xe0
[ 183.656065] do_syscall_64+0x38/0xc0
[ 183.656882] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 183.657663] RIP: 0033:0x7fe5ef725142
[ 183.659351] RSP: 002b:00007ffe1e81c7e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[ 183.660227] RAX: ffffffffffffffda RBX: 0000557055dfb780 RCX: 00007fe5ef725142
[ 183.661104] RDX: 0000000000001000 RSI: 00007ffe1e81d880 RDI: 0000000000000005
[ 183.661972] RBP: 00007ffe1e81e890 R08: 0000000000000030 R09: 0000000000000046
[ 183.662832] R10: 0000557055dfc2e0 R11: 0000000000000246 R12: 0000557055dfb1c0
[ 183.663691] R13: 00007ffe1e81e980 R14: 0000000000000000 R15: 0000000000000000

Changes since v1:
- Updated if condition with range_overflows_t [Chris Wilson]

Fixes: 9f909e215fea ("drm/i915: Implement vm_ops->access for gdb access into mmaps")
Signed-off-by: Mastan Katragadda <mastanx.katragadda@intel.com>
Suggested-by: Adam Zabrocki <adamza@microsoft.com>
Reported-by: Jackson Cody <cody.jackson@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Sudeep Dutt <sudeep.dutt@intel.com>
Cc: <stable@vger.kernel.org> # v5.8+
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
[mauld: tidy up the commit message and add Cc: stable]
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220303060428.1668844-1-mastanx.katragadda@intel.com

drm/i915: Sunset igpu legacy mmap support based on GRAPHICS_VER_FULL

The intent of the version check in the mmap ioctl was to maintain
support for existing platforms (i.e., ADL/RPL and earlier), but drop
support on all future igpu platforms. As we've seen on the dgpu side,
the hardware teams are using a more fine-grained numbering system for IP
version numbers these days, so it's possible the version number
associated with our next igpu could be some form of "12.xx" rather than
13 or higher. Comparing against the full ver.release number will ensure
the intent of the check is maintained no matter what numbering the
hardware teams settle on.

Fixes: d3f3baa3562a ("drm/i915: Reinstate the mmap ioctl for some platforms")
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220407161839.1073443-1-matthew.d.roper@intel.com
(cherry picked from commit 8e7e5c077cd57ee9a36d58c65f07257dc49a88d5)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

drm/i915/gem: add missing boundary check in vm_access

A missing bounds check in vm_access() can lead to an out-of-bounds read
or write in the adjacent memory area, since the len attribute is not
validated before the memcpy later in the function, potentially hitting:

[ 183.637831] BUG: unable to handle page fault for address: ffffc90000c86000
[ 183.637934] #PF: supervisor read access in kernel mode
[ 183.637997] #PF: error_code(0x0000) - not-present page
[ 183.638059] PGD 100000067 P4D 100000067 PUD 100258067 PMD 106341067 PTE 0
[ 183.638144] Oops: 0000 [#2] PREEMPT SMP NOPTI
[ 183.638201] CPU: 3 PID: 1790 Comm: poc Tainted: G D 5.17.0-rc6-ci-drm-11296+ #1
[ 183.638298] Hardware name: Intel Corporation CoffeeLake Client Platform/CoffeeLake H DDR4 RVP, BIOS CNLSFWR1.R00.X208.B00.1905301319 05/30/2019
[ 183.638430] RIP: 0010:memcpy_erms+0x6/0x10
[ 183.640213] RSP: 0018:ffffc90001763d48 EFLAGS: 00010246
[ 183.641117] RAX: ffff888109c14000 RBX: ffff888111bece40 RCX: 0000000000000ffc
[ 183.642029] RDX: 0000000000001000 RSI: ffffc90000c86000 RDI: ffff888109c14004
[ 183.642946] RBP: 0000000000000ffc R08: 800000000000016b R09: 0000000000000000
[ 183.643848] R10: ffffc90000c85000 R11: 0000000000000048 R12: 0000000000001000
[ 183.644742] R13: ffff888111bed190 R14: ffff888109c14000 R15: 0000000000001000
[ 183.645653] FS: 00007fe5ef807540(0000) GS:ffff88845b380000(0000) knlGS:0000000000000000
[ 183.646570] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 183.647481] CR2: ffffc90000c86000 CR3: 000000010ff02006 CR4: 00000000003706e0
[ 183.648384] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 183.649271] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 183.650142] Call Trace:
[ 183.650988] <TASK>
[ 183.651793] vm_access+0x1f0/0x2a0 [i915]
[ 183.652726] __access_remote_vm+0x224/0x380
[ 183.653561] mem_rw.isra.0+0xf9/0x190
[ 183.654402] vfs_read+0x9d/0x1b0
[ 183.655238] ksys_read+0x63/0xe0
[ 183.656065] do_syscall_64+0x38/0xc0
[ 183.656882] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 183.657663] RIP: 0033:0x7fe5ef725142
[ 183.659351] RSP: 002b:00007ffe1e81c7e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[ 183.660227] RAX: ffffffffffffffda RBX: 0000557055dfb780 RCX: 00007fe5ef725142
[ 183.661104] RDX: 0000000000001000 RSI: 00007ffe1e81d880 RDI: 0000000000000005
[ 183.661972] RBP: 00007ffe1e81e890 R08: 0000000000000030 R09: 0000000000000046
[ 183.662832] R10: 0000557055dfc2e0 R11: 0000000000000246 R12: 0000557055dfb1c0
[ 183.663691] R13: 00007ffe1e81e980 R14: 0000000000000000 R15: 0000000000000000

Changes since v1:
- Updated if condition with range_overflows_t [Chris Wilson]

Fixes: 9f909e215fea ("drm/i915: Implement vm_ops->access for gdb access into mmaps")
Signed-off-by: Mastan Katragadda <mastanx.katragadda@intel.com>
Suggested-by: Adam Zabrocki <adamza@microsoft.com>
Reported-by: Jackson Cody <cody.jackson@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Sudeep Dutt <sudeep.dutt@intel.com>
Cc: <stable@vger.kernel.org> # v5.8+
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
[mauld: tidy up the commit message and add Cc: stable]
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220303060428.1668844-1-mastanx.katragadda@intel.com
(cherry picked from commit 661412e301e2ca86799aa4f400d1cf0bd38c57c6)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

drm/i915: don't include drm_cache.h in i915_drv.h

Include it only in files that use it.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/14edab4a193ea3f73f387a88e3836c8555401871.1644507885.git.jani.nikula@intel.com

drm/i915: Add locking to i915_gem_evict_vm(), v3.

i915_gem_evict_vm will need to be able to evict objects that are
locked by the current ctx. By testing if the current context already
locked the object, we can do this correctly. This allows us to
evict the entire vm even if we already hold some objects' locks.

Previously, this was spread over several commits, but it makes
more sense to commit the changes to i915_gem_evict_vm separately
from the changes to i915_gem_evict_something() and
i915_gem_evict_for_node().

Changes since v1:
- Handle evicting dead objects better.
Changes since v2:
- Use for_i915_gem_ww in igt_evict_vm. (Thomas)

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
[mlankhorst: Fix up doc warning.]
Link: https://patchwork.freedesktop.org/patch/msgid/20220117075604.131477-1-maarten.lankhorst@linux.intel.com

drm/i915: Call i915_gem_evict_vm in vm_fault_gtt to prevent new ENOSPC errors, v2.

Now that we cannot unbind kill the currently locked object directly
because we're removing short term pinning, we may have to unbind the
object from gtt manually, using a i915_gem_evict_vm() call.

Changes since v1:
- Remove -ENOSPC warning, can still happen with concurrent mmaps
where we can't unbind the other mmap because of the lock held.
This fixes the gem_mmap_gtt@cpuset tests.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220114132320.109030-2-maarten.lankhorst@linux.intel.com

drm/i915/ttm: add unmap_virtual callback

Ensure we call ttm_bo_unmap_virtual when releasing the pages.
Importantly this should now handle the ttm swapping case, and all other
places that already call into i915_ttm_move_notify().

v2: fix up the selftest

Fixes: cf3e3e86d779 ("drm/i915: Use ttm mmap handling for ttm bo's.")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220106174910.280616-3-matthew.auld@intel.com

drm/i915/gem: Use to_gt() helper for GGTT accesses

GGTT is currently available both through i915->ggtt and gt->ggtt, and we
eventually want to get rid of the i915->ggtt one.
Use to_gt() for all i915->ggtt accesses to help with the future
refactoring.

Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Sujaritha Sundaresan <sujaritha.sundaresan@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211219212500.61432-4-andi.shyti@linux.intel.com

drm/i915/ttm: add unmap_virtual callback

Ensure we call ttm_bo_unmap_virtual when releasing the pages.
Importantly this should now handle the ttm swapping case, and all other
places that already call into i915_ttm_move_notify().

v2: fix up the selftest

Fixes: cf3e3e86d779 ("drm/i915: Use ttm mmap handling for ttm bo's.")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220106174910.280616-3-matthew.auld@intel.com
(cherry picked from commit 903e0387270eef14a711c0feb23b7bf62d2480df)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

drm/i915/gem: Use to_gt() helper

Use to_gt() helper consistently throughout the codebase.
Pure mechanical s/i915->gt/to_gt(i915). No functional changes.

Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211214193346.21231-6-andi.shyti@linux.intel.com

drm/i915: replace X86_FEATURE_PAT with pat_enabled()

PAT can be disabled on boot with "nopat" in the command line. Replace
one x86-ism with another, which is slightly more correct to prepare for
supporting other architectures.

Cc: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211202003048.1015511-1-lucas.demarchi@intel.com

drm/i915: Skip remap_io_mapping() for non-x86 platforms

Only hw that supports mappable aperture would hit this path
vm_fault_gtt/vm_fault_tmm, So we never hit this function
remap_io_mapping() in discrete, So skip this code for non-x86
architectures.

v2: use IS_ENABLED () instead of #if defined

v3: move function prototypes from i915_drv.h to i915_mm.h

v4: added kernel error message in stub function

v5: fixed compilation warnings

v6: checkpatch style

Signed-off-by: Siva Mullati <siva.mullati@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211208041215.763098-1-siva.mullati@intel.com

drm/i915: remove IS_ACTIVE

When trying to bring IS_ACTIVE to linux/kconfig.h I thought it wouldn't
provide much value just encapsulating it in a boolean context. So I also
added the support for handling undefined macros as the IS_ENABLED()
counterpart. However the feedback received from Masahiro Yamada was that
it is too ugly, not providing much value. And just wrapping in a boolean
context is too dumb - we could simply open code it.

As detailed in commit babaab2f4738 ("drm/i915: Encapsulate kconfig
constant values inside boolean predicates"), the IS_ACTIVE macro was
added to workaround a compilation warning. However after checking again
our current uses of IS_ACTIVE it turned out there is only
1 case in which it triggers a warning in clang (due
-Wconstant-logical-operand) and 2 in smatch. All the others
can simply use the shorter version, without wrapping it in any macro.

So here I'm dialing all the way back to simply removing the macro. That
single case hit by clang can be changed to make the constant come first,
so it doesn't think it's mask:

- if (context && CONFIG_DRM_I915_FENCE_TIMEOUT)
+ if (CONFIG_DRM_I915_FENCE_TIMEOUT && context)

As talked with Dan Carpenter, that logic will be added in smatch as
well, so it will also stop warning about it.

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211005171728.3147094-1-lucas.demarchi@intel.com

drm/i915/guc: Update intel_gt_wait_for_idle to work with GuC

When running the GuC the GPU can't be considered idle if the GuC still
has contexts pinned. As such, a call has been added in
intel_gt_wait_for_idle to idle the UC and in turn the GuC by waiting for
the number of unpinned contexts to go to zero.

v2: rtimeout -> remaining_timeout
v3: Drop unnecessary includes, guc_submission_busy_loop ->
guc_submission_send_busy_loop, drop negatie timeout trick, move a
refactor of guc_context_unpin to earlier path (John H)
v4: Add stddef.h back into intel_gt_requests.h, sort circuit idle
function if not in GuC submission mode

Cc: John Harrison <john.c.harrison@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210721215101.139794-16-matthew.brost@intel.com

drm/i915: Add TTM offset argument to mmap.

The FIXED mapping is only used for ttm, and tells userspace that the
mapping type is pre-defined. This disables the other type of mmap
offsets when discrete memory is used, so fix the selftests as well.

Document the struct as well, so it shows up in docbook.

Cc: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
[mauld: Included minor fixes from the review comments]
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210714122833.766586-1-maarten.lankhorst@linux.intel.com

drm/i915: Reinstate the mmap ioctl for some platforms

Reinstate the mmap ioctl for all current integrated platforms.
The intention was really to have it disabled for discrete graphics
where we enforce a single mmap mode.

This was reported to break ADL-P with the media stack, which was not the
intention. Although longer term we do still plan to sunset this ioctl
even for integrated, in favour of using mmap_offset instead.

Fixes: 35cbd91eb541 ("drm/i915: Disable mmap ioctl for gen12+")
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210624112914.311984-1-thomas.hellstrom@linux.intel.com

drm/i915: Update object placement flags to be mutable

The object ops i915_GEM_OBJECT_HAS_IOMEM and the object
I915_BO_ALLOC_STRUCT_PAGE flags are considered immutable by
much of our code. Introduce a new mem_flags member to hold these
and make sure checks for these flags being set are either done
under the object lock or with pages properly pinned. The flags
will change during migration under the object lock.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210624084240.270219-2-thomas.hellstrom@linux.intel.com

drm/i915: Use ttm mmap handling for ttm bo's.

Use the ttm handlers for servicing page faults, and vm_access.

We do our own validation of read-only access, otherwise use the
ttm handlers as much as possible.

Because the ttm handlers expect the vma_node at vma->base, we slightly
need to massage the mmap handlers to look at vma_node->driver_private
to fetch the bo, if it's NULL, we assume i915's normal mmap_offset uapi
is used.

This is the easiest way to achieve compatibility without changing ttm's
semantics.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210610070152.572423-5-thomas.hellstrom@linux.intel.com

drm/i915: Reinstate the mmap ioctl for some platforms

Reinstate the mmap ioctl for all current integrated platforms.
The intention was really to have it disabled for discrete graphics
where we enforce a single mmap mode.

This was reported to break ADL-P with the media stack, which was not the
intention. Although longer term we do still plan to sunset this ioctl
even for integrated, in favour of using mmap_offset instead.

Fixes: 35cbd91eb541 ("drm/i915: Disable mmap ioctl for gen12+")
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210624112914.311984-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit d3f3baa3562a5d09f3e87f5fdf84952112807753)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915/gem: replace IS_GEN and friends with GRAPHICS_VER

This was done by the following semantic patch:

@@ expression i915; @@
- INTEL_GEN(i915)
+ GRAPHICS_VER(i915)

@@ expression i915; expression E; @@
- INTEL_GEN(i915) >= E
+ GRAPHICS_VER(i915) >= E

@@ expression dev_priv; expression E; @@
- !IS_GEN(dev_priv, E)
+ GRAPHICS_VER(dev_priv) != E

@@ expression dev_priv; expression E; @@
- IS_GEN(dev_priv, E)
+ GRAPHICS_VER(dev_priv) == E

@@
expression dev_priv;
expression from, until;
@@
- IS_GEN_RANGE(dev_priv, from, until)
+ IS_GRAPHICS_VER(dev_priv, from, until)

@def@
expression E;
identifier id =~ "^gen$";
@@
- id = GRAPHICS_VER(E)
+ ver = GRAPHICS_VER(E)

@@
identifier def.id;
@@
- id
+ ver

It also takes care of renaming the variable we assign to GRAPHICS_VER()
so to use "ver" rather than "gen".

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210605155356.4183026-4-lucas.demarchi@intel.com

Revert "i915: use io_mapping_map_user"

This reverts commit b739f125e4ebd73d10ed30a856574e13649119ed.

We are unfortunately seeing more issues like we did in 293837b9ac8d
("Revert "i915: fix remap_io_sg to verify the pgprot""), except this is
now for the vm_fault_gtt path, where we are now hitting the same
BUG_ON(!pte_none(*pte)):

[10887.466150] kernel BUG at mm/memory.c:2183!
[10887.466162] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[10887.466168] CPU: 0 PID: 7775 Comm: ffmpeg Tainted: G U 5.13.0-rc3-CI-Nightly #1
[10887.466174] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./J4205-ITX, BIOS P1.40 07/14/2017
[10887.466177] RIP: 0010:remap_pfn_range_notrack+0x30f/0x440
[10887.466188] Code: e8 96 d7 e0 ff 84 c0 0f 84 27 01 00 00 48 ba 00 f0 ff ff ff ff 0f 00 4c 89 e0 48 c1 e0 0c 4d 85 ed 75 96 48 21 d0 31 f6 eb a9 <0f> 0b 48 39 37 0f 85 0e 01 00 00 48 8b 0c 24 48 39 4f 08 0f 85 00
[10887.466193] RSP: 0018:ffffc90006e33c50 EFLAGS: 00010286
[10887.466198] RAX: 800000000000002f RBX: 00007f5e01800000 RCX: 0000000000000028
[10887.466201] RDX: 0000000000000001 RSI: ffffea0000000000 RDI: 0000000000000000
[10887.466204] RBP: ffffea000033fea8 R08: 800000000000002f R09: ffff8881072256e0
[10887.466207] R10: ffffc9000b84fff8 R11: 0000000017dab000 R12: 0000000000089f9f
[10887.466210] R13: 800000000000002f R14: 00007f5e017e4000 R15: ffff88800cffaf20
[10887.466213] FS: 00007f5e04849640(0000) GS:ffff888278000000(0000) knlGS:0000000000000000
[10887.466216] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[10887.466220] CR2: 00007fd9b191a2ac CR3: 00000001829ac000 CR4: 00000000003506f0
[10887.466223] Call Trace:
[10887.466233] vm_fault_gtt+0x1ca/0x5d0 [i915]
[10887.466381] ? ktime_get+0x38/0x90
[10887.466389] __do_fault+0x37/0x90
[10887.466395] __handle_mm_fault+0xc46/0x1200
[10887.466402] handle_mm_fault+0xce/0x2a0
[10887.466407] do_user_addr_fault+0x1c5/0x660

Reverting this commit is reported to fix the issue.

Reported-by: Eero Tamminen <eero.t.tamminen@intel.com>
References: https://gitlab.freedesktop.org/drm/intel/-/issues/3519
Fixes: b739f125e4eb ("i915: use io_mapping_map_user")
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210527185145.458021-1-matthew.auld@intel.com

drm/i915: Disable mmap ioctl for gen12+

The platform should exclusively use mmap_offset, one less path to worry
about for discrete.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210601074654.3103-14-thomas.hellstrom@linux.intel.com

drm/i915: Avoid div-by-zero on gen2

Gen2 tiles are 2KiB in size so i915_gem_object_get_tile_row_size()
can in fact return <4KiB, which leads to div-by-zero here.
Avoid that.

Not sure i915_gem_object_get_tile_row_size() is entirely
sane anyway since it doesn't account for the different tile
layouts on i8xx/i915...

I'm not able to hit this before commit 6846895fde05 ("drm/i915:
Replace PIN_NONFAULT with calls to PIN_NOEVICT") and it looks
like I also need to run recent version of Mesa. With those in
place xonotic trips on this quite easily on my 85x.

Cc: stable@vger.kernel.org
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210421153401.13847-2-ville.syrjala@linux.intel.com

Revert "i915: use io_mapping_map_user"

This reverts commit b739f125e4ebd73d10ed30a856574e13649119ed.

We are unfortunately seeing more issues like we did in 293837b9ac8d
("Revert "i915: fix remap_io_sg to verify the pgprot""), except this is
now for the vm_fault_gtt path, where we are now hitting the same
BUG_ON(!pte_none(*pte)):

[10887.466150] kernel BUG at mm/memory.c:2183!
[10887.466162] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[10887.466168] CPU: 0 PID: 7775 Comm: ffmpeg Tainted: G U 5.13.0-rc3-CI-Nightly #1
[10887.466174] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./J4205-ITX, BIOS P1.40 07/14/2017
[10887.466177] RIP: 0010:remap_pfn_range_notrack+0x30f/0x440
[10887.466188] Code: e8 96 d7 e0 ff 84 c0 0f 84 27 01 00 00 48 ba 00 f0 ff ff ff ff 0f 00 4c 89 e0 48 c1 e0 0c 4d 85 ed 75 96 48 21 d0 31 f6 eb a9 <0f> 0b 48 39 37 0f 85 0e 01 00 00 48 8b 0c 24 48 39 4f 08 0f 85 00
[10887.466193] RSP: 0018:ffffc90006e33c50 EFLAGS: 00010286
[10887.466198] RAX: 800000000000002f RBX: 00007f5e01800000 RCX: 0000000000000028
[10887.466201] RDX: 0000000000000001 RSI: ffffea0000000000 RDI: 0000000000000000
[10887.466204] RBP: ffffea000033fea8 R08: 800000000000002f R09: ffff8881072256e0
[10887.466207] R10: ffffc9000b84fff8 R11: 0000000017dab000 R12: 0000000000089f9f
[10887.466210] R13: 800000000000002f R14: 00007f5e017e4000 R15: ffff88800cffaf20
[10887.466213] FS: 00007f5e04849640(0000) GS:ffff888278000000(0000) knlGS:0000000000000000
[10887.466216] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[10887.466220] CR2: 00007fd9b191a2ac CR3: 00000001829ac000 CR4: 00000000003506f0
[10887.466223] Call Trace:
[10887.466233] vm_fault_gtt+0x1ca/0x5d0 [i915]
[10887.466381] ? ktime_get+0x38/0x90
[10887.466389] __do_fault+0x37/0x90
[10887.466395] __handle_mm_fault+0xc46/0x1200
[10887.466402] handle_mm_fault+0xce/0x2a0
[10887.466407] do_user_addr_fault+0x1c5/0x660

Reverting this commit is reported to fix the issue.

Reported-by: Eero Tamminen <eero.t.tamminen@intel.com>
References: https://gitlab.freedesktop.org/drm/intel/-/issues/3519
Fixes: b739f125e4eb ("i915: use io_mapping_map_user")
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210527185145.458021-1-matthew.auld@intel.com
(cherry picked from commit 0e4fe0c9f2f981f26e01b73f3c465ca314c4f9c0)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

drm/i915: Avoid div-by-zero on gen2

Gen2 tiles are 2KiB in size so i915_gem_object_get_tile_row_size()
can in fact return <4KiB, which leads to div-by-zero here.
Avoid that.

Not sure i915_gem_object_get_tile_row_size() is entirely
sane anyway since it doesn't account for the different tile
layouts on i8xx/i915...

I'm not able to hit this before commit 6846895fde05 ("drm/i915:
Replace PIN_NONFAULT with calls to PIN_NOEVICT") and it looks
like I also need to run recent version of Mesa. With those in
place xonotic trips on this quite easily on my 85x.

Cc: stable@vger.kernel.org
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210421153401.13847-2-ville.syrjala@linux.intel.com
(cherry picked from commit ed52c62d386f764194e0184fdb905d5f24194cae)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

i915: use io_mapping_map_user

Replace the home-grown remap_io_mapping that abuses apply_to_page_range
with the proper io_mapping_map_user interface.

Link: https://lkml.kernel.org/r/20210326055505.1424432-4-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drm/i915: Add ww locking around vm_access()

i915_gem_object_pin_map potentially needs a ww context, so ensure we
have one we can revoke.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210323155059.628690-35-maarten.lankhorst@linux.intel.com

drm/i915: Add object locking to vm_fault_cpu

Take a simple lock so we hold ww around (un)pin_pages as needed.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210323155059.628690-24-maarten.lankhorst@linux.intel.com

drm/i915: Move HAS_STRUCT_PAGE to obj->flags

We want to remove the changing of ops structure for attaching
phys pages, so we need to kill off HAS_STRUCT_PAGE from ops->flags,
and put it in the bo.

This will remove a potential race of dereferencing the wrong obj->ops
without ww mutex held.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
[danvet: apply with wiggle]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210323155059.628690-8-maarten.lankhorst@linux.intel.com

mm: introduce vma_set_file function v5

Add the new vma_set_file() function to allow changing
vma->vm_file with the necessary refcount dance.

v2: add more users of this.
v3: add missing EXPORT_SYMBOL, rebase on mmap cleanup,
add comments why we drop the reference on two occasions.
v4: make it clear that changing an anonymous vma is illegal.
v5: move vma_set_file to mm/util.c

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v2)
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://patchwork.freedesktop.org/patch/399360/

Revert "mm: introduce vma_set_file function v4"

The kernel test robot is not happy with that.

This reverts commit 2b5b95b1ff3d70a95013a45e3b5b90f1daf42348.

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/394773/

mm: introduce vma_set_file function v4

Add the new vma_set_file() function to allow changing
vma->vm_file with the necessary refcount dance.

v2: add more users of this.
v3: add missing EXPORT_SYMBOL, rebase on mmap cleanup,
add comments why we drop the reference on two occasions.
v4: make it clear that changing an anonymous vma is illegal.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v2)
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/394773/

drm/i915: Add ww locking to vm_fault_gtt

We want to start requiring the reservation_lock instead of obj->mm.lock
for pinning objects, take the ww lock inside vm_fault_gtt as a first step
towards the legacy lock removal.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200819140904.1708856-23-maarten.lankhorst@linux.intel.com
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

drm/i915/gem: Only revoke mmap handlers if active

Avoid waking up the device and taking stale locks if we know that the
object is not currently mmapped. This is particularly useful as not many
object are actually mmapped and so we can destroy them without waking
the device up, and gives us a little more freedom of workqueue ordering
during shutdown.

v2: Pull the release_mmap() into its single user in freeing the objects,
where there can not be any race with a concurrent user of the freed
object. Or so one hopes!

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
Link: https://patchwork.freedesktop.org/patch/msgid/20200702163623.6402-2-chris@chris-wilson.co.uk

drm/i915/gem: Only revoke the GGTT mmappings on aperture detiling changes

Only a GGTT mmapping will use the aperture detiling registers, so on a
tiling change for an object, we only need to revoke those mmappings and
not the CPU mmappings (which are always linear irrespective of the tiling).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702163623.6402-1-chris@chris-wilson.co.uk

mmap locking API: use coccinelle to convert mmap_sem rwsem call sites

This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drm/i915/gem: Retry faulthandlers on ENOSPC

As we no longer use the shmemfs allocation directly, we do not expect to
receive -ENOSPC from a backing store allocation. The potential sources
for -ENOSPC are then our own internal eviction code, so the choice is
either to kill the potential application with SIGBUS or to retry the
faulthandler.

In this patch we retry the fault handler, but since this is a should
never happen condition, it is arguable that we gather up copious debug
and kill the application. At worst, we cause an interruptible busy-wait,
stalling the application -- all causes should be transient and the
system should eventually recover. A small stall is hopefully a better
outcome than random oomkiller.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515200031.12034-1-chris@chris-wilson.co.uk

drm/i915: Implement vm_ops->access for gdb access into mmaps

gdb uses ptrace() to peek and poke bytes of the target's address space.
The driver must implement an vm_ops->access() handler or else gdb will
be unable to inspect the pointer and report it as out-of-bounds.
Worse than useless as it causes immediate suspicion of the valid GTT
pointer, distracting the poor programmer trying to find his bug.

v2: Write-protect readonly objects (Matthew).

Testcase: igt/gem_mmap_gtt/ptrace
Testcase: igt/gem_mmap_offset/ptrace
Suggested-by: Kristian H. Kristensen <hoegsberg@google.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Maciej Patelczyk <maciej.patelczyk@intel.com>
Cc: Kristian H. Kristensen <hoegsberg@google.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200501145120.18830-1-chris@chris-wilson.co.uk

drm/i915/gem: Mark up the racy read of the mmap_singleton

[11057.642683] BUG: KCSAN: data-race in i915_gem_mmap [i915] / singleton_release [i915]
[11057.642717]
[11057.642740] write (marked) to 0xffff8881f24471a0 of 8 bytes by task 44668 on cpu 2:
[11057.643162] singleton_release+0x38/0x60 [i915]
[11057.643192] __fput+0x160/0x3c0
[11057.643217] ____fput+0x16/0x20
[11057.643241] task_work_run+0xba/0x100
[11057.643263] exit_to_usermode_loop+0xe4/0xf0
[11057.643286] do_syscall_64+0x27e/0x2c0
[11057.643314] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[11057.643339]
[11057.643359] read to 0xffff8881f24471a0 of 8 bytes by task 44667 on cpu 3:
[11057.643774] i915_gem_mmap+0x295/0x670 [i915]
[11057.643802] mmap_region+0x62b/0xac0
[11057.643825] do_mmap+0x414/0x6b0
[11057.643848] vm_mmap_pgoff+0xa9/0xf0
[11057.643875] ksys_mmap_pgoff+0x1ac/0x2f0
[11057.643900] do_syscall_64+0x6e/0x2c0
[11057.643924] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200311092624.10012-3-chris@chris-wilson.co.uk

drm/i915/gem: Tighten checks and acquiring the mmap object

Make sure we hold the rcu lock as we acquire the rcu protected reference
of the object when looking it up from the associated mmap vma.

Closes: https://gitlab.freedesktop.org/drm/intel/issues/1083
Fixes: cc662126b413 ("drm/i915: Introduce DRM_I915_GEM_MMAP_OFFSET")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200130143931.1906301-1-chris@chris-wilson.co.uk
(cherry picked from commit 280d14a69da2e71f43408537c008f2775d5e5360)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

drm/i915/gem: Store mmap_offsets in an rbtree rather than a plain list

Currently we create a new mmap_offset for every call to
mmap_offset_ioctl. This exposes ourselves to an abusive client that may
simply create new mmap_offsets ad infinitum, which will exhaust physical
memory and the virtual address space. In addition to the exhaustion, a
very long linear list of mmap_offsets causes other clients using the
object to incur long list walks -- these long lists can also be
generated by simply having many clients generate their own mmap_offset.

However, we can simply use the drm_vma_node itself to manage the file
association (allow/revoke) dropping our need to keep an mmo per-file.
Then if we keep a small rbtree of per-type mmap_offsets, we can lookup
duplicate requests quickly.

Fixes: cc662126b413 ("drm/i915: Introduce DRM_I915_GEM_MMAP_OFFSET")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Reviewed-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200120104924.4000706-3-chris@chris-wilson.co.uk
(cherry picked from commit 7865559872074a9ab169c87915504661d630addf)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

drm/i915: Never allow userptr into the new mapping types

Commit 4f2a572eda67 ("drm/i915/userptr: Never allow userptr into the
mappable GGTT") made I915_GEM_MMAP_GTT IOCTLs to fail when attempted
on a userptr object in order to protect from a lockdep splat. Later
on, new mapping types were introduced by commit cc662126b413
("drm/i915: Introduce DRM_I915_GEM_MMAP_OFFSET"). Those new mapping
types suffer from the same lockdep splat issue but they now succeed
when tried on top of a userptr object. Fix it.

v2: Don't play with the -ENODEV driver response (Chris)

Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200204162302.1299516-1-chris@chris-wilson.co.uk

drm/i915/gem: Tighten checks and acquiring the mmap object

Make sure we hold the rcu lock as we acquire the rcu protected reference
of the object when looking it up from the associated mmap vma.

Closes: https://gitlab.freedesktop.org/drm/intel/issues/1083
Fixes: cc662126b413 ("drm/i915: Introduce DRM_I915_GEM_MMAP_OFFSET")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200130143931.1906301-1-chris@chris-wilson.co.uk

drm/i915/gem: Store mmap_offsets in an rbtree rather than a plain list

Currently we create a new mmap_offset for every call to
mmap_offset_ioctl. This exposes ourselves to an abusive client that may
simply create new mmap_offsets ad infinitum, which will exhaust physical
memory and the virtual address space. In addition to the exhaustion, a
very long linear list of mmap_offsets causes other clients using the
object to incur long list walks -- these long lists can also be
generated by simply having many clients generate their own mmap_offset.

However, we can simply use the drm_vma_node itself to manage the file
association (allow/revoke) dropping our need to keep an mmo per-file.
Then if we keep a small rbtree of per-type mmap_offsets, we can lookup
duplicate requests quickly.

Fixes: cc662126b413 ("drm/i915: Introduce DRM_I915_GEM_MMAP_OFFSET")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Reviewed-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200120104924.4000706-3-chris@chris-wilson.co.uk

drm/i915/gem: Extend mmap support for lmem

Local memory objects are similar to our usual scatterlist, but instead
of using the struct page stored therein, we need to use the
sg->dma_address.

Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200103204137.2131004-1-chris@chris-wilson.co.uk

drm/i915/gem: Drop local vma->vm_file reference

We use the global device inode, shared amongst all files, and not the
user's device filp to provide the backing storage for the mmap. The
vma->vm_file provides a redundant reference that breaks existing
expected behaviour that closing the user's device fd will release the
resources bound to it, if a mmap persists. (Even without the
vma->vm_file, the mmap will persist past the user's fd as the storage is
bound to the device, i.e. our reference is on the object not file.)

Fixes: cc662126b413 ("drm/i915: Introduce DRM_I915_GEM_MMAP_OFFSET")
Closes: https://gitlab.freedesktop.org/drm/intel/issues/919
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200101141007.755429-1-chris@chris-wilson.co.uk

drm/i915: Introduce remap_io_sg() to prefault discontiguous objects

Provide a way to set the PTE within apply_page_range for discontiguous
objects in addition to the existing method of just incrementing the pfn
for a page range.

Fixes: cc662126b413 ("drm/i915: Introduce DRM_I915_GEM_MMAP_OFFSET")
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191231200356.409475-1-chris@chris-wilson.co.uk

drm/i915/gem: Comment on inability to check args.pad for MMAP_OFFSET

Since we didn't check and insist that args.pad must be zero for MMAP_GTT
historically, we cannot insert a check now as old userspace may be
feeding in garbage. As such the lack of check is enshrined into the ABI,
so add a comment to remind us we cannot add the check later.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191207222644.2830129-1-chris@chris-wilson.co.uk

drm/i915/gem: Hook user-extensions upto MMAP_OFFSET_IOCTL

Call i915_user_extensions() to validate the arg->extensions pointer, and
so return consistent error numbers for the future.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191204162803.3841140-1-chris@chris-wilson.co.uk

drm/i915: Introduce DRM_I915_GEM_MMAP_OFFSET

This is really just an alias of mmap_gtt. The 'mmap offset' nomenclature
comes from the value returned by this ioctl which is the offset into the
device fd which userpace uses with mmap(2).

mmap_gtt was our initial mmap_offset implementation, this extends
our CPU mmap support to allow additional fault handlers that depends on
the object's backing pages.

Note that we multiplex mmap_gtt and mmap_offset through the same ioctl,
and use the zero extending behaviour of drm to differentiate between
them, when we inspect the flags.

To support multiple mmap types on an object we need to support multiple
mmap_offsets for an object (each offset in the global device address
space corresponding to a unique instance of the object for a file + mmap
type). As we drop the simplified drm core idea of a single mmap_offset,
we need to provide replacement hooks for the dumb mmap interface as
well.

Link: https://gitlab.freedesktop.org/mesa/mesa/merge_requests/1675
Testcase: igt/gem_mmap_offset
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191204120032.3682839-1-chris@chris-wilson.co.uk

drm/i915/gem: Early rejection of no-aperture map_ggtt

If the device does not have an aperture through which we can indirectly
access and detile the buffers, simply reject the ioctl. Later we can
extend the ioctl to support different modes, but as an extension the
user must opt in and explicitly control the mmap type (viz
MMAP_OFFSET_IOCTL).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191105145305.14314-1-chris@chris-wilson.co.uk

drm/i915: Encapsulate kconfig constant values inside boolean predicates

Avoid angering clang and smatch by using a constant value in a '&&' test,
by forcing that constant value into a boolean.

E.g.,
drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c:159:13: warning: use of logical '&&' with constant operand [-Wconstant-logical-operand]
if (!delay && CONFIG_DRM_I915_PREEMPT_TIMEOUT) {
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191025135943.12524-1-chris@chris-wilson.co.uk

drm/i915/userptr: Never allow userptr into the mappable GGTT

Daniel Vetter uncovered a nasty cycle in using the mmu-notifiers to
invalidate userptr objects which also happen to be pulled into GGTT
mmaps. That is when we unbind the userptr object (on mmu invalidation),
we revoke all CPU mmaps, which may then recurse into mmu invalidation.

We looked for ways of breaking the cycle, but the revocation on
invalidation is required and cannot be avoided. The only solution we
could see was to not allow such GGTT bindings of userptr objects in the
first place. In practice, no one really wants to use a GGTT mmapping of
a CPU pointer...

Just before Daniel's explosive lockdep patches land in v5.4-rc1, we got
a genuine blip from CI:

<4>[ 246.793958] ======================================================
<4>[ 246.793972] WARNING: possible circular locking dependency detected
<4>[ 246.793989] 5.3.0-gbd6c56f50d15-drmtip_372+ #1 Tainted: G U
<4>[ 246.794003] ------------------------------------------------------
<4>[ 246.794017] kswapd0/145 is trying to acquire lock:
<4>[ 246.794030] 000000003f565be6 (&dev->struct_mutex/1){+.+.}, at: userptr_mn_invalidate_range_start+0x18f/0x220 [i915]
<4>[ 246.794250]
but task is already holding lock:
<4>[ 246.794263] 000000001799cef9 (&anon_vma->rwsem){++++}, at: page_lock_anon_vma_read+0xe6/0x2a0
<4>[ 246.794291]
which lock already depends on the new lock.

<4>[ 246.794307]
the existing dependency chain (in reverse order) is:
<4>[ 246.794322]
-> #3 (&anon_vma->rwsem){++++}:
<4>[ 246.794344] down_write+0x33/0x70
<4>[ 246.794357] __vma_adjust+0x3d9/0x7b0
<4>[ 246.794370] __split_vma+0x16a/0x180
<4>[ 246.794385] mprotect_fixup+0x2a5/0x320
<4>[ 246.794399] do_mprotect_pkey+0x208/0x2e0
<4>[ 246.794413] __x64_sys_mprotect+0x16/0x20
<4>[ 246.794429] do_syscall_64+0x55/0x1c0
<4>[ 246.794443] entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4>[ 246.794456]
-> #2 (&mapping->i_mmap_rwsem){++++}:
<4>[ 246.794478] down_write+0x33/0x70
<4>[ 246.794493] unmap_mapping_pages+0x48/0x130
<4>[ 246.794519] i915_vma_revoke_mmap+0x81/0x1b0 [i915]
<4>[ 246.794519] i915_vma_unbind+0x11d/0x4a0 [i915]
<4>[ 246.794519] i915_vma_destroy+0x31/0x300 [i915]
<4>[ 246.794519] __i915_gem_free_objects+0xb8/0x4b0 [i915]
<4>[ 246.794519] drm_file_free.part.0+0x1e6/0x290
<4>[ 246.794519] drm_release+0xa6/0xe0
<4>[ 246.794519] __fput+0xc2/0x250
<4>[ 246.794519] task_work_run+0x82/0xb0
<4>[ 246.794519] do_exit+0x35b/0xdb0
<4>[ 246.794519] do_group_exit+0x34/0xb0
<4>[ 246.794519] __x64_sys_exit_group+0xf/0x10
<4>[ 246.794519] do_syscall_64+0x55/0x1c0
<4>[ 246.794519] entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4>[ 246.794519]
-> #1 (&vm->mutex){+.+.}:
<4>[ 246.794519] i915_gem_shrinker_taints_mutex+0x6d/0xe0 [i915]
<4>[ 246.794519] i915_address_space_init+0x9f/0x160 [i915]
<4>[ 246.794519] i915_ggtt_init_hw+0x55/0x170 [i915]
<4>[ 246.794519] i915_driver_probe+0xc9f/0x1620 [i915]
<4>[ 246.794519] i915_pci_probe+0x43/0x1b0 [i915]
<4>[ 246.794519] pci_device_probe+0x9e/0x120
<4>[ 246.794519] really_probe+0xea/0x3d0
<4>[ 246.794519] driver_probe_device+0x10b/0x120
<4>[ 246.794519] device_driver_attach+0x4a/0x50
<4>[ 246.794519] __driver_attach+0x97/0x130
<4>[ 246.794519] bus_for_each_dev+0x74/0xc0
<4>[ 246.794519] bus_add_driver+0x13f/0x210
<4>[ 246.794519] driver_register+0x56/0xe0
<4>[ 246.794519] do_one_initcall+0x58/0x300
<4>[ 246.794519] do_init_module+0x56/0x1f6
<4>[ 246.794519] load_module+0x25bd/0x2a40
<4>[ 246.794519] __se_sys_finit_module+0xd3/0xf0
<4>[ 246.794519] do_syscall_64+0x55/0x1c0
<4>[ 246.794519] entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4>[ 246.794519]
-> #0 (&dev->struct_mutex/1){+.+.}:
<4>[ 246.794519] __lock_acquire+0x15d8/0x1e90
<4>[ 246.794519] lock_acquire+0xa6/0x1c0
<4>[ 246.794519] __mutex_lock+0x9d/0x9b0
<4>[ 246.794519] userptr_mn_invalidate_range_start+0x18f/0x220 [i915]
<4>[ 246.794519] __mmu_notifier_invalidate_range_start+0x85/0x110
<4>[ 246.794519] try_to_unmap_one+0x76b/0x860
<4>[ 246.794519] rmap_walk_anon+0x104/0x280
<4>[ 246.794519] try_to_unmap+0xc0/0xf0
<4>[ 246.794519] shrink_page_list+0x561/0xc10
<4>[ 246.794519] shrink_inactive_list+0x220/0x440
<4>[ 246.794519] shrink_node_memcg+0x36e/0x740
<4>[ 246.794519] shrink_node+0xcb/0x490
<4>[ 246.794519] balance_pgdat+0x241/0x580
<4>[ 246.794519] kswapd+0x16c/0x530
<4>[ 246.794519] kthread+0x119/0x130
<4>[ 246.794519] ret_from_fork+0x24/0x50
<4>[ 246.794519]
other info that might help us debug this:

<4>[ 246.794519] Chain exists of:
&dev->struct_mutex/1 --> &mapping->i_mmap_rwsem --> &anon_vma->rwsem

<4>[ 246.794519] Possible unsafe locking scenario:

<4>[ 246.794519] CPU0 CPU1
<4>[ 246.794519] ---- ----
<4>[ 246.794519] lock(&anon_vma->rwsem);
<4>[ 246.794519] lock(&mapping->i_mmap_rwsem);
<4>[ 246.794519] lock(&anon_vma->rwsem);
<4>[ 246.794519] lock(&dev->struct_mutex/1);
<4>[ 246.794519]
*** DEADLOCK ***

v2: Say no to mmap_ioctl

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111744
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111870
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190928082546.3473-1-chris@chris-wilson.co.uk
(cherry picked from commit a4311745bba9763e3c965643d4531bd5765b0513)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915: Mark contents as dirty on a write fault

Since dropping the set-to-gtt-domain in commit a679f58d0510 ("drm/i915:
Flush pages on acquisition"), we no longer mark the contents as dirty on
a write fault. This has the issue of us then not marking the pages as
dirty on releasing the buffer, which means the contents are not written
out to the swap device (should we ever pick that buffer as a victim).
Notably, this is visible in the dumb buffer interface used for cursors.
Having updated the cursor contents via mmap, and swapped away, if the
shrinker should evict the old cursor, upon next reuse, the cursor would
be invisible.

E.g. echo 80 > /proc/sys/kernel/sysrq ; echo f > /proc/sysrq-trigger

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111541
Fixes: a679f58d0510 ("drm/i915: Flush pages on acquisition")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.2+
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190920121821.7223-1-chris@chris-wilson.co.uk
(cherry picked from commit 5028851cdfdf78dc22eacbc44a0ab0b3f599ee4a)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915: Don't mix srcu tag and negative error codes

While srcu may use an integer tag, it does not exclude potential error
codes and so may overlap with our own use of -EINTR. Use a separate
outparam to store the tag, and report the error code separately.

Fixes: 2caffbf11762 ("drm/i915: Revoke mmaps and prevent access to fence registers across reset")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190912160834.30601-1-chris@chris-wilson.co.uk
(cherry picked from commit eebab60f224fcfd560957715d08c31564d8672ed)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915: Move request runtime management onto gt

Requests are run from the gt and are tided into the gt runtime power
management, so pull the runtime request management under gt/

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-12-chris@chris-wilson.co.uk

drm/i915/gem: Retire directly for mmap-offset shrinking

Now that we can retire without taking struct_mutex, we can do so to
handle shrinking the mmap-offset space after an allocation failure.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-11-chris@chris-wilson.co.uk

drm/i915: Merge wait_for_timelines with retire_request

wait_for_timelines is essentially the same loop as retiring requests
(with an extra timeout), so merge the two into one routine.

v2: i915_retire_requests_timeout and keep VT'd w/a as !interruptible

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-10-chris@chris-wilson.co.uk

drm/i915: Pull i915_vma_pin under the vm->mutex

Replace the struct_mutex requirement for pinning the i915_vma with the
local vm->mutex instead. Note that the vm->mutex is tainted by the
shrinker (we require unbinding from inside fs-reclaim) and so we cannot
allocate while holding that mutex. Instead we have to preallocate
workers to do allocate and apply the PTE updates after we have we
reserved their slot in the drm_mm (using fences to order the PTE writes
with the GPU work and with later unbind).

In adding the asynchronous vma binding, one subtle requirement is to
avoid coupling the binding fence into the backing object->resv. That is
the asynchronous binding only applies to the vma timeline itself and not
to the pages as that is a more global timeline (the binding of one vma
does not need to be ordered with another vma, nor does the implicit GEM
fencing depend on a vma, only on writes to the backing store). Keeping
the vma binding distinct from the backing store timelines is verified by
a number of async gem_exec_fence and gem_exec_schedule tests. The way we
do this is quite simple, we keep the fence for the vma binding separate
and only wait on it as required, and never add it to the obj->resv
itself.

Another consequence in reducing the locking around the vma is the
destruction of the vma is no longer globally serialised by struct_mutex.
A natural solution would be to add a kref to i915_vma, but that requires
decoupling the reference cycles, possibly by introducing a new
i915_mm_pages object that is own by both obj->mm and vma->pages.
However, we have not taken that route due to the overshadowing lmem/ttm
discussions, and instead play a series of complicated games with
trylocks to (hopefully) ensure that only one destruction path is called!

v2: Add some commentary, and some helpers to reduce patch churn.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-4-chris@chris-wilson.co.uk

drm/i915/userptr: Never allow userptr into the mappable GGTT

Daniel Vetter uncovered a nasty cycle in using the mmu-notifiers to
invalidate userptr objects which also happen to be pulled into GGTT
mmaps. That is when we unbind the userptr object (on mmu invalidation),
we revoke all CPU mmaps, which may then recurse into mmu invalidation.

We looked for ways of breaking the cycle, but the revocation on
invalidation is required and cannot be avoided. The only solution we
could see was to not allow such GGTT bindings of userptr objects in the
first place. In practice, no one really wants to use a GGTT mmapping of
a CPU pointer...

Just before Daniel's explosive lockdep patches land in v5.4-rc1, we got
a genuine blip from CI:

<4>[ 246.793958] ======================================================
<4>[ 246.793972] WARNING: possible circular locking dependency detected
<4>[ 246.793989] 5.3.0-gbd6c56f50d15-drmtip_372+ #1 Tainted: G U
<4>[ 246.794003] ------------------------------------------------------
<4>[ 246.794017] kswapd0/145 is trying to acquire lock:
<4>[ 246.794030] 000000003f565be6 (&dev->struct_mutex/1){+.+.}, at: userptr_mn_invalidate_range_start+0x18f/0x220 [i915]
<4>[ 246.794250]
but task is already holding lock:
<4>[ 246.794263] 000000001799cef9 (&anon_vma->rwsem){++++}, at: page_lock_anon_vma_read+0xe6/0x2a0
<4>[ 246.794291]
which lock already depends on the new lock.

<4>[ 246.794307]
the existing dependency chain (in reverse order) is:
<4>[ 246.794322]
-> #3 (&anon_vma->rwsem){++++}:
<4>[ 246.794344] down_write+0x33/0x70
<4>[ 246.794357] __vma_adjust+0x3d9/0x7b0
<4>[ 246.794370] __split_vma+0x16a/0x180
<4>[ 246.794385] mprotect_fixup+0x2a5/0x320
<4>[ 246.794399] do_mprotect_pkey+0x208/0x2e0
<4>[ 246.794413] __x64_sys_mprotect+0x16/0x20
<4>[ 246.794429] do_syscall_64+0x55/0x1c0
<4>[ 246.794443] entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4>[ 246.794456]
-> #2 (&mapping->i_mmap_rwsem){++++}:
<4>[ 246.794478] down_write+0x33/0x70
<4>[ 246.794493] unmap_mapping_pages+0x48/0x130
<4>[ 246.794519] i915_vma_revoke_mmap+0x81/0x1b0 [i915]
<4>[ 246.794519] i915_vma_unbind+0x11d/0x4a0 [i915]
<4>[ 246.794519] i915_vma_destroy+0x31/0x300 [i915]
<4>[ 246.794519] __i915_gem_free_objects+0xb8/0x4b0 [i915]
<4>[ 246.794519] drm_file_free.part.0+0x1e6/0x290
<4>[ 246.794519] drm_release+0xa6/0xe0
<4>[ 246.794519] __fput+0xc2/0x250
<4>[ 246.794519] task_work_run+0x82/0xb0
<4>[ 246.794519] do_exit+0x35b/0xdb0
<4>[ 246.794519] do_group_exit+0x34/0xb0
<4>[ 246.794519] __x64_sys_exit_group+0xf/0x10
<4>[ 246.794519] do_syscall_64+0x55/0x1c0
<4>[ 246.794519] entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4>[ 246.794519]
-> #1 (&vm->mutex){+.+.}:
<4>[ 246.794519] i915_gem_shrinker_taints_mutex+0x6d/0xe0 [i915]
<4>[ 246.794519] i915_address_space_init+0x9f/0x160 [i915]
<4>[ 246.794519] i915_ggtt_init_hw+0x55/0x170 [i915]
<4>[ 246.794519] i915_driver_probe+0xc9f/0x1620 [i915]
<4>[ 246.794519] i915_pci_probe+0x43/0x1b0 [i915]
<4>[ 246.794519] pci_device_probe+0x9e/0x120
<4>[ 246.794519] really_probe+0xea/0x3d0
<4>[ 246.794519] driver_probe_device+0x10b/0x120
<4>[ 246.794519] device_driver_attach+0x4a/0x50
<4>[ 246.794519] __driver_attach+0x97/0x130
<4>[ 246.794519] bus_for_each_dev+0x74/0xc0
<4>[ 246.794519] bus_add_driver+0x13f/0x210
<4>[ 246.794519] driver_register+0x56/0xe0
<4>[ 246.794519] do_one_initcall+0x58/0x300
<4>[ 246.794519] do_init_module+0x56/0x1f6
<4>[ 246.794519] load_module+0x25bd/0x2a40
<4>[ 246.794519] __se_sys_finit_module+0xd3/0xf0
<4>[ 246.794519] do_syscall_64+0x55/0x1c0
<4>[ 246.794519] entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4>[ 246.794519]
-> #0 (&dev->struct_mutex/1){+.+.}:
<4>[ 246.794519] __lock_acquire+0x15d8/0x1e90
<4>[ 246.794519] lock_acquire+0xa6/0x1c0
<4>[ 246.794519] __mutex_lock+0x9d/0x9b0
<4>[ 246.794519] userptr_mn_invalidate_range_start+0x18f/0x220 [i915]
<4>[ 246.794519] __mmu_notifier_invalidate_range_start+0x85/0x110
<4>[ 246.794519] try_to_unmap_one+0x76b/0x860
<4>[ 246.794519] rmap_walk_anon+0x104/0x280
<4>[ 246.794519] try_to_unmap+0xc0/0xf0
<4>[ 246.794519] shrink_page_list+0x561/0xc10
<4>[ 246.794519] shrink_inactive_list+0x220/0x440
<4>[ 246.794519] shrink_node_memcg+0x36e/0x740
<4>[ 246.794519] shrink_node+0xcb/0x490
<4>[ 246.794519] balance_pgdat+0x241/0x580
<4>[ 246.794519] kswapd+0x16c/0x530
<4>[ 246.794519] kthread+0x119/0x130
<4>[ 246.794519] ret_from_fork+0x24/0x50
<4>[ 246.794519]
other info that might help us debug this:

<4>[ 246.794519] Chain exists of:
&dev->struct_mutex/1 --> &mapping->i_mmap_rwsem --> &anon_vma->rwsem

<4>[ 246.794519] Possible unsafe locking scenario:

<4>[ 246.794519] CPU0 CPU1
<4>[ 246.794519] ---- ----
<4>[ 246.794519] lock(&anon_vma->rwsem);
<4>[ 246.794519] lock(&mapping->i_mmap_rwsem);
<4>[ 246.794519] lock(&anon_vma->rwsem);
<4>[ 246.794519] lock(&dev->struct_mutex/1);
<4>[ 246.794519]
*** DEADLOCK ***

v2: Say no to mmap_ioctl

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111744
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111870
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190928082546.3473-1-chris@chris-wilson.co.uk

drm/i915: Mark contents as dirty on a write fault

Since dropping the set-to-gtt-domain in commit a679f58d0510 ("drm/i915:
Flush pages on acquisition"), we no longer mark the contents as dirty on
a write fault. This has the issue of us then not marking the pages as
dirty on releasing the buffer, which means the contents are not written
out to the swap device (should we ever pick that buffer as a victim).
Notably, this is visible in the dumb buffer interface used for cursors.
Having updated the cursor contents via mmap, and swapped away, if the
shrinker should evict the old cursor, upon next reuse, the cursor would
be invisible.

E.g. echo 80 > /proc/sys/kernel/sysrq ; echo f > /proc/sysrq-trigger

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111541
Fixes: a679f58d0510 ("drm/i915: Flush pages on acquisition")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.2+
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190920121821.7223-1-chris@chris-wilson.co.uk

drm/i915: Don't mix srcu tag and negative error codes

While srcu may use an integer tag, it does not exclude potential error
codes and so may overlap with our own use of -EINTR. Use a separate
outparam to store the tag, and report the error code separately.

Fixes: 2caffbf11762 ("drm/i915: Revoke mmaps and prevent access to fence registers across reset")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190912160834.30601-1-chris@chris-wilson.co.uk

drm/i915: Use NOEVICT for first pass on attemping to pin a GGTT mmap

The intention is that we first try to pin the current vma into the
mappable aperture only if it is already in use or it fits in the free
space and will not cause contention. The first attempt was meant to be
using PIN_NOEVICT to reuse the current vma if possible, following up
with different eviction strategies.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111485
Fixes: 6846895fde05 ("drm/i915: Replace PIN_NONFAULT with calls to PIN_NOEVICT")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190826130750.17272-1-chris@chris-wilson.co.uk
(cherry picked from commit ebfdf5cd806b3bbf1ff79e69bce6a28df8bbe39d)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drm/i915: Refresh the errno to vmf_fault translations

It's been a long time since we accidentally reported -EIO upon wedging,
it can now only be generated by failure to swap in a page.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Reviewed-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190902040303.14195-4-chris@chris-wilson.co.uk

drm/i915: Use NOEVICT for first pass on attemping to pin a GGTT mmap

The intention is that we first try to pin the current vma into the
mappable aperture only if it is already in use or it fits in the free
space and will not cause contention. The first attempt was meant to be
using PIN_NOEVICT to reuse the current vma if possible, following up
with different eviction strategies.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111485
Fixes: 6846895fde05 ("drm/i915: Replace PIN_NONFAULT with calls to PIN_NOEVICT")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190826130750.17272-1-chris@chris-wilson.co.uk

drm/i915: Pull obj->userfault tracking under the ggtt->mutex

Since we want to revoke the ggtt vma from only under the ggtt->mutex, we
need to move protection of the userfault tracking from the struct_mutex
to the ggtt->mutex.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190822060914.2671-2-chris@chris-wilson.co.uk

drm/i915: Replace PIN_NONFAULT with calls to PIN_NOEVICT

When under severe stress for GTT mappable space, the LRU eviction model
falls off a cliff. We spend all our time scanning the much larger
non-mappable area searching for something within the mappable zone we can
evict. Turn this on its head by only using the full vma for the object if
it is already pinned in the mappable zone or there is sufficient *free*
space to accommodate it (prioritizing speedy reuse). If there is not,
immediately fall back to using small chunks (tilerow for GTT mmap, single
pages for pwrite/relocation) and using random eviction before doing a full
search.

Testcase: igt/gem_concurrent_blt
References: https://bugs.freedesktop.org/show_bug.cgi?id=110848
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190821123234.19194-1-chris@chris-wilson.co.uk

drm/i915: Extract intel_frontbuffer active tracking

Move the active tracking for the frontbuffer operations out of the
i915_gem_object and into its own first class (refcounted) object. In the
process of detangling, we switch from low level request tracking to the
easier i915_active -- with the plan that this avoids any potential
atomic callbacks as the frontbuffer tracking wishes to sleep as it
flushes.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190816074635.26062-1-chris@chris-wilson.co.uk

drm/i915: remove unnecessary includes of intel_display_types.h header

With its original name intel_drv.h the intel_display_types.h header was
superfluously cargo-cult included all over the place, while it's really
mostly about display internals. Remove the unnecessary includes.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/e3d737f0ab87c55969e62c1e077e15c04c238297.1565085692.git.jani.nikula@intel.com

drm/i915: rename intel_drv.h to display/intel_display_types.h

Everything about the file is about display, and mostly about types
related to display. Move under display/ as intel_display_types.h to
reflect the facts.

There's still plenty to clean up, but start off with moving the file
where it logically belongs and naming according to contents.

v2: fix the include guard name in the renamed file

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190806113933.11799-1-jani.nikula@intel.com

drm/i915: avoid including intel_drv.h via i915_drv.h->i915_trace.h

Disentangle i915_drv.h from intel_drv.h, which gets included via
i915_trace.h. This necessitates including i915_trace.h wherever it's
needed.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ed82bf259d3b725a1a1a3c3e9d6fb5c08bc4d489.1565085691.git.jani.nikula@intel.com

drm/i915: Mark expected switch fall-throughs

In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

This patch fixes the following warnings:

drivers/gpu/drm/i915/gem/i915_gem_mman.c: In function ‘i915_gem_fault’:
drivers/gpu/drm/i915/gem/i915_gem_mman.c:342:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (!i915_terminally_wedged(i915))
^
drivers/gpu/drm/i915/gem/i915_gem_mman.c:345:2: note: here
case -EAGAIN:
^~~~

drivers/gpu/drm/i915/gem/i915_gem_pages.c: In function ‘i915_gem_object_map’:
./include/linux/compiler.h:78:22: warning: this statement may fall through [-Wimplicit-fallthrough=]
# define unlikely(x) __builtin_expect(!!(x), 0)
^~~~~~~~~~~~~~~~~~~~~~~~~~
./include/asm-generic/bug.h:136:2: note: in expansion of macro ‘unlikely’
unlikely(__ret_warn_on); \
^~~~~~~~
drivers/gpu/drm/i915/i915_utils.h:49:25: note: in expansion of macro ‘WARN’
#define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \
^~~~
drivers/gpu/drm/i915/gem/i915_gem_pages.c:270:3: note: in expansion of macro ‘MISSING_CASE’
MISSING_CASE(type);
^~~~~~~~~~~~
drivers/gpu/drm/i915/gem/i915_gem_pages.c:272:2: note: here
case I915_MAP_WB:
^~~~

drivers/gpu/drm/i915/i915_gpu_error.c: In function ‘error_record_engine_registers’:
./include/linux/compiler.h:78:22: warning: this statement may fall through [-Wimplicit-fallthrough=]
# define unlikely(x) __builtin_expect(!!(x), 0)
^~~~~~~~~~~~~~~~~~~~~~~~~~
./include/asm-generic/bug.h:136:2: note: in expansion of macro ‘unlikely’
unlikely(__ret_warn_on); \
^~~~~~~~
drivers/gpu/drm/i915/i915_utils.h:49:25: note: in expansion of macro ‘WARN’
#define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \
^~~~
drivers/gpu/drm/i915/i915_gpu_error.c:1196:5: note: in expansion of macro ‘MISSING_CASE’
MISSING_CASE(engine->id);
^~~~~~~~~~~~
drivers/gpu/drm/i915/i915_gpu_error.c:1197:4: note: here
case RCS0:
^~~~

drivers/gpu/drm/i915/display/intel_dp.c: In function ‘intel_dp_get_fia_supported_lane_count’:
./include/linux/compiler.h:78:22: warning: this statement may fall through [-Wimplicit-fallthrough=]
# define unlikely(x) __builtin_expect(!!(x), 0)
^~~~~~~~~~~~~~~~~~~~~~~~~~
./include/asm-generic/bug.h:136:2: note: in expansion of macro ‘unlikely’
unlikely(__ret_warn_on); \
^~~~~~~~
drivers/gpu/drm/i915/i915_utils.h:49:25: note: in expansion of macro ‘WARN’
#define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \
^~~~
drivers/gpu/drm/i915/display/intel_dp.c:233:3: note: in expansion of macro ‘MISSING_CASE’
MISSING_CASE(lane_info);
^~~~~~~~~~~~
drivers/gpu/drm/i915/display/intel_dp.c:234:2: note: here
case 1:
^~~~

drivers/gpu/drm/i915/display/intel_display.c: In function ‘check_digital_port_conflicts’:
CC [M] drivers/gpu/drm/nouveau/nvkm/engine/disp/cursgv100.o
drivers/gpu/drm/i915/display/intel_display.c:12043:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (WARN_ON(!HAS_DDI(to_i915(dev))))
^
drivers/gpu/drm/i915/display/intel_display.c:12046:3: note: here
case INTEL_OUTPUT_DP:
^~~~

Also, notice that the Makefile is modified to stop ignoring
fall-through warnings. The -Wimplicit-fallthrough option
will be enabled globally in v5.3.

Warning level 3 was used: -Wimplicit-fallthrough=3

This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

drm/i915/gt: Use intel_gt as the primary object for handling resets

Having taken the first step in encapsulating the functionality by moving
the related files under gt/, the next step is to start encapsulating by
passing around the relevant structs rather than the global
drm_i915_private. In this step, we pass intel_gt to intel_reset.c

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190712192953.9187-1-chris@chris-wilson.co.uk

drm/i915: update rpm_get/put to use the rpm structure

The functions where internally already only using the structure, so we
need to just flip the interface.

v2: rebase

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613232156.34940-7-daniele.ceraolospurio@intel.com

drm/i915: Remove rpm asserts that use i915

Quite a few of the call points have already switched to the version
working directly on the runtime_pm structure, so let's switch over the
rest and kill the i915-based asserts.

v2: rebase

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613232156.34940-3-daniele.ceraolospurio@intel.com

drm/i915: Move fence register tracking from i915->mm to ggtt

As the fence registers only apply to regions inside the GGTT is makes
more sense that we track these as part of the i915_ggtt and not the
general mm. In the next patch, we will then pull the register locking
underneath the i915_ggtt.mutex.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613073254.24048-1-chris@chris-wilson.co.uk

drm/i915: Move mmap and friends to its own file

Continuing the decluttering of i915_gem.c, now the turn of do_mmap and
the faulthandlers

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190528092956.14910-6-chris@chris-wilson.co.uk