diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2020-01-20 10:49:22 +0000 |
|---|---|---|
| committer | Jani Nikula <jani.nikula@intel.com> | 2020-02-11 11:49:31 +0200 |
| commit | 07ccd6bdafa22aacc4f72b7eb14474d0b356e6c3 (patch) | |
| tree | 2ce00ad8a95c698dadb75c41c30adfd7542f0db0 /drivers/gpu/drm/i915/gem/i915_gem_object_types.h | |
| parent | a754012b9f2323a5d640da7eb7b095ac3b8cd012 (diff) | |
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>
Diffstat (limited to 'drivers/gpu/drm/i915/gem/i915_gem_object_types.h')
| -rw-r--r-- | drivers/gpu/drm/i915/gem/i915_gem_object_types.h | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h index 88e268633fdc..f64ad77e6b1e 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h @@ -71,13 +71,11 @@ enum i915_mmap_type { }; struct i915_mmap_offset { - struct drm_device *dev; struct drm_vma_offset_node vma_node; struct drm_i915_gem_object *obj; - struct drm_file *file; enum i915_mmap_type mmap_type; - struct list_head offset; + struct rb_node offset; }; struct drm_i915_gem_object { @@ -137,7 +135,7 @@ struct drm_i915_gem_object { struct { spinlock_t lock; /* Protects access to mmo offsets */ - struct list_head offsets; + struct rb_root offsets; } mmo; I915_SELFTEST_DECLARE(struct list_head st_link); |