Using an order 19 drm_ht for the mmap offsets is a little obscene. That
means that will a fully populated GTT with every single object mmaped at
least once in its lifetime, there will be exactly one object in each
bucket.

Typically systems only have at most a few thousand objects, though you
may see a KDE desktop hit 50000. And most of those should never be
mapped... On my systems, just using an order 10 ht would still have an
average occupancy less than 1, so apply a small safety factor and
use an order 12 ht, like the other mmap offset ht.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This is just an idea that might or might not be a good idea,
it basically adds two ioctls to create a dumb and map a dumb buffer
suitable for scanout. The handle can be passed to the KMS ioctls to create
a framebuffer.

It looks to me like it would be useful in the following cases:
a) in development drivers - we can always provide a shadowfb fallback.
b) libkms users - we can clean up libkms a lot and avoid linking
to libdrm_*.
c) plymouth via libkms is a lot easier.

Userspace bits would be just calls + mmaps. We could probably
mark these handles somehow as not being suitable for acceleartion
so as top stop people who are dumber than dumb.
Signed-off-by: NDave Airlie <airlied@redhat.com>

Only drm/i915 does the bookkeeping that makes the information useful,
and the information maintained is driver specific, so move it out of the
core and into its single user.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Airlie <airlied@redhat.com>

In order to be fully threadsafe we need to check that the drm_gem_object
refcount is still 0 after acquiring the mutex in order to call the free
function. Otherwise, we may encounter scenarios like:

Thread A:                                        Thread B:
drm_gem_close
unreference_unlocked
kref_put                                         mutex_lock
...                                              i915_gem_evict
...                                              kref_get -> BUG
...                                              i915_gem_unbind
...                                              kref_put
...                                              i915_gem_object_free
...                                              mutex_unlock
mutex_lock
i915_gem_object_free -> BUG
i915_gem_object_unbind
kfree
mutex_unlock

Note that no driver is currently using the free_unlocked vfunc and it is
scheduled for removal, hasten that process.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=30454Reported-and-Tested-by: NMagnus Kessler <Magnus.Kessler@gmx.net>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
Signed-off-by: NDave Airlie <airlied@redhat.com>

There were lots of places being inconsistent since handle count
looked like a kref but it really wasn't.

Fix this my just making handle count an atomic on the object,
and have it increase the normal object kref.

Now i915/radeon/nouveau drivers can drop the normal reference on
userspace object creation, and have the handle hold it.

This patch fixes a memory leak or corruption on unload, because
the driver had no way of knowing if a handle had been actually
added for this object, and the fbcon object needed to know this
to clean itself up properly.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Hook the GEM vm open/close ops into the generic drm vm open/close so
that the private vma entries are created and destroy appropriately.
Fixes the leak of the drm_vma_entries during the lifetime of the filp.
Reported-by: NMatt Mackall <mpm@selenic.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Cc: stable@kernel.org
Signed-off-by: NDave Airlie <airlied@redhat.com>

Not used by any current driver.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This is consistent with trying to access a filename that not exist
within a directory which is a good analogy here. The main reason for the
change is that it is easy to confuse the error code of EBADF as an
performing an ioctl on an invalid file descriptor (rather than an
unknown object).
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDave Airlie <airlied@redhat.com>

/* A typical clean-up sequence for objects stored in an idr tree, will
 * use idr_for_each() to free all objects, if necessary, then
 * idr_remove_all() to remove all ids, and idr_destroy() to free
 * up the cached idr_layers.
 */

We were missing the vital idr_rmove_all() step and so were leaking
the used layers for every dri client:

unreferenced object 0xf32133c0 (size 148):
  comm "plymouthd", pid 131, jiffies 4294678490 (age 2308.030s)
  hex dump (first 32 bytes):
    04 00 00 00 00 00 00 00 00 00 00 00 00 40 19 f3  .............@..
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<c04e5657>] create_object+0x124/0x1f1
    [<c07cf100>] kmemleak_alloc+0x4c/0x90
    [<c04db6a9>] kmem_cache_alloc+0xee/0x13c
    [<c05c3d25>] idr_pre_get+0x24/0x61
    [<f8315c9c>] drm_gem_handle_create+0x27/0x7f [drm]
    [<f89925b2>] i915_gem_create_ioctl+0x4f/0x71 [i915]
    [<f83148ac>] drm_ioctl+0x272/0x356 [drm]
    [<c04f27c4>] vfs_ioctl+0x33/0x91
    [<c04f31cf>] do_vfs_ioctl+0x46b/0x496
    [<c04f3240>] sys_ioctl+0x46/0x66
    [<c040325f>] sysenter_do_call+0x12/0x38
    [<ffffffff>] 0xffffffff

Fixes https://bugzilla.kernel.org/show_bug.cgi?id=15803Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The pgoff option in mmap() is defined as an unsigned long
so the offset generated by DRM needs to fit into
BITS_PER_LONG for the CPU in question.
Signed-off-by: NJordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

When drivers embed the core gem object into their own structures,
they'll have to do this. Temporarily this results in an ugly

kfree(gem_obj);

in every gem driver.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This function can be used by drivers who allocate the drm gem object
on their own. No functional change in here, just preparation.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Mostly obvious simplifications.

The i915 pread/pwrite ioctls, intel_overlay_put_image and
nouveau_gem_new were incorrectly using the locked versions
without locking: this is also fixed in this patch.
Signed-off-by: NLuca Barbieri <luca@luca-barbieri.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This patch introduces the drm_gem_object_unreference_unlocked
and drm_gem_object_handle_unreference_unlocked functions that
do not require holding struct_mutex.

drm_gem_object_unreference_unlocked calls the new
->gem_free_object_unlocked entry point if available, and
otherwise just takes struct_mutex and just calls ->gem_free_object
Signed-off-by: NLuca Barbieri <luca@luca-barbieri.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Having missed the ENOMEM return via i915_gem_fault(), there are probably
other paths that I also missed. By not enabling NORETRY by default these
paths can run the shrinker and take memory from the system (but not from
our own inactive lists because our shrinker can not run whilst we hold
the struct mutex) and this may allow the system to survive a little longer
whilst our drivers consume all available memory.

References:
  OOM killer unexpectedly called with kernel 2.6.32
  http://bugzilla.kernel.org/show_bug.cgi?id=14933

v2: Pass gfp into page mapping.
v3: Use new read_cache_page_gfp() instead of open-coding.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Eric Anholt <eric@anholt.net>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some architectures compute ->vm_page_prot depending on ->vm_flags, so we
need to update the protections after adjusting the flags.

AFAIK this only affects running X under Xen; without this patch you get
lots of coloured blobs on the screen, or maybe a complete lockup.  Or
anything really.

But that still depends on lots of out-of-tree stuff, so I don't think
there are any consequences for anyone else.  But it is wrong in principle.
Reported-by: NJan Beulich <JBeulich@novell.com>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Due to the necessity of having to take the struct_mutex, the i915
shrinker can not free the inactive lists if we fail to allocate memory
whilst processing a batch buffer, triggering an OOM and an ENOMEM that
is reported back to userspace. In order to fare better under such
circumstances we need to manually retry a failed allocation after
evicting inactive buffers.

To do so involves 3 steps:
1. Marking the backing shm pages as NORETRY.
2. Updating the get_pages() callers to evict something on failure and then
   retry.
3. Revamping the evict something logic to be smarter about the required
   buffer size and prefer to use volatile or clean inactive pages.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Several functions in the GEM kernel API used int as handle type, but
user API has it __u32 which is also the intended type.

Replace int with u32.
Signed-off-by: NPekka Paalanen <pq@iki.fi>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Check kzalloc retval against NULL in drm_gem_object_alloc and bail out
appropriately.

While at it merge the fail paths and jump to them by gotos at the end
of the function.
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Signed-off-by: NDave Airlie <airlied@linux.ie>

It hasn't been used in ages, and having the user tell your how much
memory is being freed at free time is a recipe for disaster even if it
was ever used.
Signed-off-by: NEric Anholt <eric@anholt.net>

Calls to kcalloc() for a single element can be simplified to calls to
kzalloc().
Signed-off-by: NRobert P. J. Day <rpjday@crashcourse.ca>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Eric Anholt <eric@anholt.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Otherwise, the PAGE_CACHE_WC would end up getting us a UC-only mapping, and
the write performance of GTT maps dropped 10x.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[anholt: cleaned up unused var]
Signed-off-by: NEric Anholt <eric@anholt.net>

Once upon a time, the DRM made the distinction between the drm_map
data structure exchanged with user space and the drm_local_map used
in the kernel.

For some reasons, while the BSD port still has that "feature", the
linux part abused drm_map for kernel internal usage as the local
map only existed as a typedef of the struct drm_map.

This patch fixes it by declaring struct drm_local_map separately
(though its content is currently identical to the userspace variant),
and changing the kernel code to only use that, except when it's a
user<->kernel interface (ie. ioctl).

This allows subsequent changes to the in-kernel format

I've also replaced the use of drm_local_map_t with struct drm_local_map
in a couple of places. Mostly by accident but they are the same (the
former is a typedef of the later) and I have some remote plans and
half finished patch to completely kill the drm_local_map_t typedef
so I left those bits in.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@linux.ie>

This fixes potential fault at fault time if the object was unreferenced
while the mapping still existed.  Now, while the mmap_offset only lives
for the lifetime of the object, the object also stays alive while a vma
exists that needs it.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>

The name table should only hold a single reference, so avoid leaking
additional references for secondary calls to flink().
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@linux.ie>

Ensure that the object is unreferenced if we fail to allocate during
drm_gem_flink_ioctl().
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@linux.ie>

Remove the member from the hash table before we free the structure!
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@linux.ie>

The mmap_region() code would temporarily set the VM_ACCOUNT flag for
anonymous shared mappings just to inform shmem_zero_setup() that it
should enable accounting for the resulting shm object.  It would then
clear the flag after calling ->mmap (for the /dev/zero case) or doing
shmem_zero_setup() (for the MAP_ANON case).

This just resulted in vma merge issues, but also made for just
unnecessary confusion.  Use the already-existing VM_NORESERVE flag for
this instead, and let shmem_{zero|file}_setup() just figure it out from
that.

This also happens to make it obvious that the new DRI2 GEM layer uses a
non-reserving backing store for its object allocation - which is quite
possibly not intentional.  But since I didn't want to change semantics
in this patch, I left it alone, and just updated the caller to use the
new flag semantics.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The page protections need to be checked whether they need to be more flexible.
Signed-off-by: NDave Airlie <airlied@redhat.com>

Add core support for mapping of GEM objects.  Drivers should provide a
vm_operations_struct if they want to support page faulting of objects.
The code for handling GEM object offsets was taken from TTM, which was
written by Thomas Hellström.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Signed-off-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>

GEM allows the creation of persistent buffer objects accessible by the
graphics device through new ioctls for managing execution of commands on the
device.  The userland API is almost entirely driver-specific to ensure that
any driver building on this model can easily map the interface to individual
driver requirements.

GEM is used by the 2d driver for managing its internal state allocations and
will be used for pixmap storage to reduce memory consumption and enable
zero-copy GLX_EXT_texture_from_pixmap, and in the 3d driver is used to enable
GL_EXT_framebuffer_object and GL_ARB_pixel_buffer_object.
Signed-off-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>