Dma-bufs should already be device coherent, as they are only pulled in the
CPU domain via the begin/end cpu_access calls. As we cache the mapping set
up by dma_map_sg a CPU sync at this point will not actually guarantee proper
coherency on non-coherent architectures, so we can as well stop pretending.
This is an important performance fix for architectures which need explicit
cache synchronization and userspace doing lots of dma-buf imports.
Improves Weston on Etnaviv performance 5x, where before this patch > 90%
of Weston CPU time was spent synchronizing caches for buffers which are
already device coherent.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171130173428.8666-1-l.stach@pengutronix.de
This is a continuation of a previous commit ("drm: introduce drm_dev_{get/put}
functions") to replace all references to drm_dev_unref() in drm core files with
drm_dev_put().
Signed-off-by: Aishwarya Pant <aishpant@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20170926170400.GA7671@aishwarya
Reference counting functions in the kernel typically use get/put suffixes. For
maintaining coding style consistency, introduce drm_dev_{get/put} functions. All
callers of drm_dev_ref() API have been converted in this patch and hence it has
been dropped while the drm_dev_unref() API with non-trivial number of users
remains for compatibility.
The semantic patch scripts/coccinelle/api/drm-get-put.cocci has been updated
with the new helper for conversion of drm_dev_unref() to drm_dev_put()
Signed-off-by: Aishwarya Pant <aishpant@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/6babda56134035a98220d5d37a4fd4048df214ce.1506413698.git.aishpant@gmail.com
The existing drm_gem_prime_import function uses the underlying
struct device of a drm_device for attaching to a dma_buf. Some drivers
(notably vgem) may not have an underlying device structure. Offer
an alternate function to attach using any available device structure.
Signed-off-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1493923548-20878-3-git-send-email-labbott@redhat.com
Seeing the kunmap_atomic dma_buf_ops share the same name with a macro
in highmem.h, the former can be aliased if any dma-buf user includes
that header.
I'm personally trying to include highmem.h inside scatterlist.h and this
breaks the dma-buf code proper.
Christoph Hellwig suggested [1] renaming it and pushing this patch ASAP.
To maintain consistency I've renamed all four of kmap* and kunmap* to be
map* and unmap*. (Even though only kmap_atomic presently conflicts.)
[1] https://www.spinics.net/lists/target-devel/msg15070.html
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1492630570-879-1-git-send-email-logang@deltatee.com
For consistency with other reference counting APIs in the kernel, add
drm_gem_object_get() and drm_gem_object_put(), as well as an unlocked
variant of the latter, to reference count GEM buffer objects.
Compatibility aliases are added to keep existing code working. To help
speed up the transition, all the instances of the old functions in the
DRM core are already replaced in this commit.
The existing semantic patch for the DRM subsystem-wide conversion is
extended to account for these new helpers.
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170228144643.5668-6-thierry.reding@gmail.com
From the description of the "DMA-BUF/GEM Object references
and lifetime overview" it is not clear when exactly
dma_buf gets destroyed and memory freed: only driver
.release function mentioned which makes confusion on the
real buffer's lifetime.
Add more description so all the paths are covered.
Cc: Rob Clark <robdclark@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
[danvet: Minor spelling fixes, and some clarification of the 2nd
paragraph.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1485500665-27690-1-git-send-email-andr2000@gmail.com
I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).
Also some minor drive-by polish where it makes sense, I read a lot
of docs ...
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-5-daniel.vetter@ffwll.ch
Currently the reference for the dmabuf->obj is incremented for the
dmabuf in drm_gem_prime_handle_to_fd() (at the high level userspace
interface), but is released in drm_gem_dmabuf_release() (the lowlevel
handler). Improve the symmetry of the dmabuf->obj ownership by acquiring
the reference in drm_gem_dmabuf_export(). This makes it easier to use
the prime functions directly.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Update kerneldoc.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161207214527.22533-1-chris@chris-wilson.co.uk
I hit send before completing a make htmldoc, and lo I forgot to fix up
the cut'n'paste.
Fixes: a4fce9cb78 ("drm/prime: Take a ref on the drm_dev when exporting...")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161005174056.29869-1-chris@chris-wilson.co.uk
dma_buf may live a long time, longer than the last direct user of the
driver. We already hold a reference to the owner module (that prevents
the object code from disappearing), but there is no reference to the
drm_dev - so the pointers to the driver backend themselves may vanish.
v2: Resist temptation to fix the bug in armada_gem.c not setting the
correct flags on the exported dma-buf (it should pass the flags through
and not be arbitrarily setting O_RDWR).
Use a common wrapper for exporting the dmabuf and acquiring the
reference to the drm_device.
Testcase: igt/vgem_basic/unload
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Petri Latvala <petri.latvala@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Tested-by: Petri Latvala <petri.latvala@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161005122145.1507-2-chris@chris-wilson.co.uk
dma_buf_export() adds a reference to the owning module to the dmabuf (to
prevent the driver from being unloaded whilst a third party still refers
to the dmabuf). However, drm_gem_prime_export() was passing its own
THIS_MODULE (i.e. drm.ko) rather than the driver. Extract the right
owner from the device->fops instead.
v2: Use C99 initializers to zero out unset elements of
dma_buf_export_info
v3: Extract the right module from dev->fops.
Testcase: igt/vgem_basic/unload
Reported-by: Petri Latvala <petri.latvala@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Petri Latvala <petri.latvala@intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: stable@vger.kernel.org
Tested-by: Petri Latvala <petri.latvala@intel.com>
Reviewed-by: Petri Latvala <petri.latvala@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161005122145.1507-1-chris@chris-wilson.co.uk
Currently we use a linear walk to lookup a handle and return a dma-buf,
and vice versa. A long overdue TODO task is to convert that to a
hashtable. Since the initial implementation of dma-buf/prime, we now
have resizeable hashtables we can use (and now a future task is to RCU
enable the lookup!). However, this patch opts to use an rbtree instead
to provide O(lgN) lookups (and insertion, deletion). rbtrees were chosen
over using the RCU backed resizable hashtable to firstly avoid the
reallocations (rbtrees can be embedded entirely within the parent
struct) and to favour simpler code with predictable worst case
behaviour. In simple testing, the difference between using the constant
lookup and insertion of the rhashtable and the rbtree was less than 10%
of the wall time (igt/benchmarks/prime_lookup) - both are dramatic
improvements over the existing linear lists.
v2: Favour rbtree over rhashtable
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=94631
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20160926204414.23222-1-chris@chris-wilson.co.uk
There were a couple messed up things about this fail path.
(1) it would drop object_name_lock twice
(2) drm_gem_handle_delete() (in drm_gem_remove_prime_handles())
needs to grab prime_lock
Reported-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1465500559-17873-1-git-send-email-robdclark@gmail.com
drm_gem_object_lookup() has never required the drm_device for its file
local translation of the user handle to the GEM object. Let's remove the
unused parameter and save some space.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: dri-devel@lists.freedesktop.org
Cc: Dave Airlie <airlied@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
[danvet: Fixup kerneldoc too.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Currently DRM_IOCTL_PRIME_HANDLE_TO_FD rejects all flags except
(DRM|O)_CLOEXEC making it difficult (maybe impossible) for userspace
to mmap() the resulting dma-buf even when this is supported by the
DRM driver.
It is trivial to relax the restriction and permit read/write access.
This is safe because the flags are seldom touched by drm; mostly they
are passed verbatim to dma_buf calls.
v3 (Tiago): removed unused flags variable from drm_prime_handle_to_fd_ioctl.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Tiago Vignatti <tiago.vignatti@intel.com>
Reviewed-by: Stéphane Marchesin <marcheu@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1450820214-12509-2-git-send-email-tiago.vignatti@intel.com
DRM Docbook is now Markdown ready. This means its doc is able to
use markdown text on it.
* Documentation/DocBook/drm.tmpl: Contains a table duplicated from
drivers/gpu/drm/i915/i915_reg.h. This is not needed anymore
* drivers/gpu/drm/drm_modeset_lock.c: had a code example that used
to look pretty bad on html. Fixed by using proper code markup.
* drivers/gpu/drm/drm_prime.c: Remove spaces between lines to make
a proper markup list.
* drivers/gpu/drm/i915/i915_reg.h: Altought pandoc supports tables,
it doesn't support table cell spanning. But we can use fixed-width
for those special cases.
* include/drm/drm_vma_manager.h: Another code example that should be
proper indented with four spaces.
v2 (Daniel): Adjust name to gpu.xml due to rename.
v3 (Daniel):
Split out the actual enabling in the Makefile - this way we can merge
the conversion, while just keeping the enabling in a drm-private tree.
Signed-off-by: Danilo Cesar Lemes de Paula <danilo.cesar@collabora.co.uk> (v1)
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Stephan Mueller <smueller@chronox.de>
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kernel@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: intel-gfx <intel-gfx@lists.freedesktop.org>
Cc: dri-devel <dri-devel@lists.freedesktop.org>
Acked-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448471279-19748-2-git-send-email-daniel.vetter@ffwll.ch
gem_prime_map is not currently described in the DRM manual, lets document
it.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Currently drm_gem_prime_import() checks if gem_prime_import_sg_table()
is implemented in DRM driver ops. However it is not necessary for
internal imports (i.e. dma_buf->ops == &drm_gem_prime_dmabuf_ops
and obj->dev == dev), which only increment reference count on respective
GEM objects.
This patch makes the helper check this condition only in case of
external imports fo rwhich importing sg table is indeed needed.
Signed-off-by: Tomasz Figa <tfiga@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
At present, dma_buf_export() takes a series of parameters, which
makes it difficult to add any new parameters for exporters, if required.
Make it simpler by moving all these parameters into a struct, and pass
the struct * as parameter to dma_buf_export().
While at it, unite dma_buf_export_named() with dma_buf_export(), and
change all callers accordingly.
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
This is a small collection of fixes that I've been carrying around for a
while now. Many of these have been posted and reviewed or acked. The few
that haven't I deemed too trivial to bother.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=OUaP
-----END PGP SIGNATURE-----
Merge tag 'drm/fixes/for-3.19-rc1' of git://people.freedesktop.org/~tagr/linux into drm-next
drm: Miscellaneous fixes for v3.19-rc1
This is a small collection of fixes that I've been carrying around for a
while now. Many of these have been posted and reviewed or acked. The few
that haven't I deemed too trivial to bother.
* tag 'drm/fixes/for-3.19-rc1' of git://people.freedesktop.org/~tagr/linux:
video/hdmi: Relicense header under MIT license
drm/gma500: mdfld: Reuse video/mipi_display.h
drm: Make drm_mode_create_tv_properties() signature consistent
drm: Implement drm_get_pci_dev() dummy for !PCI
drm/prime: Use unsigned type for number of pages
drm/gem: Fix typo in kerneldoc
drm: Use const data when creating blob properties
drm: Use size_t for blob property sizes
The number of pages can never be negative, so an unsigned type is
enough. This also matches the type of the n_pages argument of the
sg_alloc_table_from_pages() function.
Signed-off-by: Thierry Reding <treding@nvidia.com>
This patch fix spelling typos found in drm.xml.
It is because the file is generated from comments in
source codes, I have to fix the typos within source files.
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
v2: Don't forget git add, noticed by David.
Cc: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Acked-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This way drivers can't grow crazy ideas any more, and it also
helps a bit in reviewing EXPORT_SYMBOLS.
v2: Even more stuff. Unfortunately we can't move drm_vm_open_locked
because exynos does some horrible stuff with it.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This allows reservation objects to be used in dma-buf. it's required
for implementing polling support on the fences that belong to a dma-buf.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Mauro Carvalho Chehab <m.chehab@samsung.com> #drivers/media/v4l2-core/
Acked-by: Thomas Hellstrom <thellstrom@vmware.com> #drivers/gpu/drm/ttm
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net> #drivers/gpu/drm/armada/
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For giant hilarity the DocBook reference overview is only generated
when in a level 2 section, not in a level 3 section. So we need to
move this up a bit as a side-by-side section to the main PRIME
documentation.
Whatever.
To have a complete set of references add the missing kerneldoc for all
functions exported to modules with the exception of the file private
init/destroy functions - drivers have no business calling those, so
let's just drop the EXPORT_SYMBOL instead.
Also reflow the function parameters to align correctly and break at 80
chars - my OCD couldn't stand them while writing the kerneldoc ;-)
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
dma_buf_map_attachment and dma_buf_vmap can return NULL or
ERR_PTR on a error. This encourages a common buggy pattern in
callers:
sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
if (IS_ERR_OR_NULL(sgt))
return PTR_ERR(sgt);
This causes the caller to return 0 on an error. IS_ERR_OR_NULL
is almost always a sign of poorly-defined error handling.
This patch converts dma_buf_map_attachment to always return
ERR_PTR, and fixes the callers that incorrectly handled NULL.
There are a few more callers that were not checking for NULL
at all, which would have dereferenced a NULL pointer later.
There are also a few more callers that correctly handled NULL
and ERR_PTR differently, I left those alone but they could also
be modified to delete the NULL check.
This patch also converts dma_buf_vmap to always return NULL.
All the callers to dma_buf_vmap only check for NULL, and would
have dereferenced an ERR_PTR and panic'd if one was ever
returned. This is not consistent with the rest of the dma buf
APIs, but matches the expectations of all of the callers.
Signed-off-by: Colin Cross <ccross@android.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a typo so deadlocks on error instead of unlocking.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@gmail.com>
... not only when the dma-buf is freshly created. In contrived
examples someone else could have exported/imported the dma-buf already
and handed us the gem object with a flink name. If such on object gets
reexported as a dma_buf we won't have it in the handle cache already,
which breaks the guarantee that for dma-buf imports we always hand
back an existing handle if there is one.
This is exercised by igt/prime_self_import/with_one_bo_two_files
Now if we extend the locked sections just a notch more we can also
plug th racy buf/handle cache setup in handle_to_fd:
If evil userspace races a concurrent gem close against a prime export
operation we can end up tearing down the gem handle before the dma buf
handle cache is set up. When handle_to_fd gets around to adding the
handle to the cache there will be no one left to clean it up,
effectily leaking the bo (and the dma-buf, since the handle cache
holds a ref on the dma-buf):
Thread A Thread B
handle_to_fd:
lookup gem object from handle
creates new dma_buf
gem_close on the same handle
obj->dma_buf is set, but file priv buf
handle cache has no entry
obj->handle_count drops to 0
drm_prime_add_buf_handle sets up the handle cache
-> We have a dma-buf reference in the handle cache, but since the
handle_count of the gem object already dropped to 0 no on will clean
it up. When closing the drm device fd we'll hit the WARN_ON in
drm_prime_destroy_file_private.
The important change is to extend the critical section of the
filp->prime.lock to cover the gem handle lookup. This serializes with
a concurrent gem handle close.
This leak is exercised by igt/prime_self_import/export-vs-gem_close-race
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
... and move it to the top of the function to avoid a forward
declaration.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The export dma-buf cache is semantically similar to an flink name. So
semantically it makes sense to treat it the same and remove the name
(i.e. the dma_buf pointer) and its references when the last gem handle
disappears.
Again we need to be careful, but double so: Not just could someone
race and export with a gem close ioctl (so we need to recheck
obj->handle_count again when assigning the new name), but multiple
exports can also race against each another. This is prevented by
holding the dev->object_name_lock across the entire section which
touches obj->dma_buf.
With the new scheme we also need to reinstate the obj->dma_buf link at
import time (in case the only reference userspace has held in-between
was through the dma-buf fd and not through any native gem handle). For
simplicity we don't check whether it's a native object but
unconditionally set up that link - with the new scheme of removing the
obj->dma_buf reference when the last handle disappears we can do that.
To make it clear that this is not just for exported buffers anymore
als rename it from export_dma_buf to dma_buf.
To make sure that now one can race a fd_to_handle or handle_to_fd with
gem_close we use the same tricks as in flink of extending the
dev->object_name_locking critical section. With this change we finally
have a guaranteed 1:1 relationship (at least for native objects)
between gem objects and dma-bufs, even accounting for races (which can
happen since the dma-buf itself holds a reference while in-flight).
This prevent igt/prime_self_import/export-vs-gem_close-race from
Oopsing the kernel. There is still a leak though since the per-file
priv dma-buf/handle cache handling is racy. That will be fixed in a
later patch.
v2: Remove the bogus dma_buf_put from the export_and_register_object
failure path if we've raced with the handle count dropping to 0.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
if (!ret) implies that ret == 0, so no need to clear it again. And
explicitly check for ret == 0 to indicate that we're checking an errno
integer.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
When exporting a gem object as a dma-buf the critical section for the
per-fd prime lock is just the adding (and in case of errors, removing)
of the handle to the per-fd lookup cache.
So restrict the critical section to just that part of the function.
This simplifies later reordering.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Part of the function uses the properly-typed dmabuf variable, the
other an untyped void *buf. Kill the later.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
handle_unreference only clears up the obj->name and the reference,
but would leave a dangling handle in the idr. The right thing
to do is to call handle_delete.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
I've checked both implementations (radeon/nouveau) and they both grab
the page array from ttm simply by dereferencing it and then wrapping
it up with drm_prime_pages_to_sg in the callback and map it with
dma_map_sg (in the helper).
Only the grabbing of the underlying page array is anything we need to
be concerned about, and either those pages are pinned independently,
or we're screwed no matter what.
And indeed, nouveau/radeon pin the backing storage in their
attach/detach functions.
Since I've created this patch cma prime support for dma_buf was added.
drm_gem_cma_prime_get_sg_table only calls kzalloc and the creates&maps
the sg table with dma_get_sgtable. It doesn't touch any gem object
state otherwise. So the cma helpers also look safe.
The only thing we might claim it does is prevent concurrent mapping of
dma_buf attachments. But a) that's not allowed and b) the current code
is racy already since it checks whether the sg mapping exists _before_
grabbing the lock.
So the dev->struct_mutex locking here does absolutely nothing useful,
but only distracts. Remove it.
This should also help Maarten's work to eventually pin the backing
storage more dynamically by preventing locking inversions around
dev->struct_mutex.
v2: Add analysis for recently added cma helper prime code.
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Note that this is slightly tricky since both drivers store their
native objects in dma_buf->priv. But both also embed the base
drm_gem_object at the first position, so the implicit cast is ok.
To use the release helper we need to export it, too.
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Intel Graphics Development <intel-gfx@lists.freedesktop.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This adds to call low-level mmap() from prime helpers.
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The drm_gem_map_detach() can be called with sgt is NULL.
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
In
commit da34242e5e
Author: YoungJun Cho <yj44.cho@samsung.com>
Date: Wed Jun 26 10:21:42 2013 +0900
drm/prime: add return check for dma_buf_fd
the failure case handling was fixed up. But in the case when we
already had the buffer exported it changed the return value:
Previously we've return 0 on success, now we return the fd.
This ABI change has been caught by i-g-t/prime_self_import/with_one_bo.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66436
Cc: YoungJun Cho <yj44.cho@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Tested-by: lu hua <huax.lu@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: YoungJun Cho <yj44.cho@samsung.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Samuel Li