linux-stable.git/drivers/dma-buf/sync_file.c, branch linux-4.9.y

dma-buf: Fix memory leak in sync_file_merge()

2019-12-21T09:42:32+00:00

commit 6645d42d79d33e8a9fe262660a75d5f4556bbea9 upstream.

In the implementation of sync_file_merge() the allocated sync_file is
leaked if number of fences overflows. Release sync_file by goto err.

Fixes: a02b9dc90d84 ("dma-buf/sync_file: refactor fence storage in struct sync_file")
Signed-off-by: Navid Emamdoost 
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20191122220957.30427-1-navid.emamdoost@gmail.com
Signed-off-by: Greg Kroah-Hartman

dma-buf: Update kerneldoc for sync_file_create

2017-12-09T21:01:56+00:00

commit 24a367348a017555f982a9ee137070a7a821fa97 upstream.

This was missed when adding a dma_fence_get call. While at it also
remove the kerneldoc for the static inline helper - no point
documenting internals down to every detail.

Fixes: 30cd85dd6edc ("dma-buf/sync_file: hold reference to fence when creating sync_file")
Cc: Gustavo Padovan 
Cc: Sean Paul 
Cc: linux-doc@vger.kernel.org
Cc: Jonathan Corbet 
Cc: Sumit Semwal 
Signed-off-by: Daniel Vetter 
Reviewed-by: Gustavo Padovan 
Signed-off-by: Sumit Semwal 
Link: http://patchwork.freedesktop.org/patch/msgid/20161209185309.1682-3-daniel.vetter@ffwll.ch
Signed-off-by: Greg Kroah-Hartman

dma-buf/sync_file: hold reference to fence when creating sync_file

2017-12-09T21:01:56+00:00

commit 30cd85dd6edc86ea8d8589efb813f1fad41ef233 upstream.

fence referencing was out of balance. It was not taking any ref to the
fence at creating time, but it was putting a reference when freeing the
sync file.

This patch fixes the balancing issue by getting a reference for the fence
when creating the sync_file.

Signed-off-by: Gustavo Padovan 
Signed-off-by: Sean Paul 
Link: http://patchwork.freedesktop.org/patch/msgid/1476899313-22241-1-git-send-email-gustavo@padovan.org
Signed-off-by: Greg Kroah-Hartman

dma-fence: Wrap querying the fence->status

2017-12-09T21:01:56+00:00

commit d6c99f4bf093a58d3ab47caaec74b81f18bc4e3f upstream.

The fence->status is an optional field that is only valid once the fence
has been signaled. (Driver may fill the fence->status with an error code
prior to calling dma_fence_signal().) Given the restriction upon its
validity, wrap querying of the fence->status into a helper
dma_fence_get_status().

Signed-off-by: Chris Wilson 
Reviewed-by: Daniel Vetter 
Reviewed-by: Sumit Semwal 
Signed-off-by: Sumit Semwal 
Link: http://patchwork.freedesktop.org/patch/msgid/20170104141222.6992-2-chris@chris-wilson.co.uk
[s/dma_fence/fence/g - gregkh]
Cc: Jisheng Zhang 
Signed-off-by: Greg Kroah-Hartman

dma-buf/sync_file: free fences array in num_fences is 1

2016-09-22T11:06:16+00:00

When merging sync_files there is a case when we can end up with only one
fence in the merged sync_file: when all fences belong to the same
timeline.

So for this case a fence_array is not created instead we just assigned the
fence to sync_file->fence. Then we do not use the fences array anymore nor
does free it.

This patch frees the array.

Reported-by:  Chris Wilson 
Reviewed-by: Chris Wilson 
Signed-off-by: Gustavo Padovan 
Signed-off-by: Sean Paul 
Link: http://patchwork.freedesktop.org/patch/msgid/1474442419-6040-1-git-send-email-gustavo@padovan.org

dma-buf/sync_file: Increment refcount of fence when all are signaled.

2016-09-20T12:23:39+00:00

When we merge several fences, if all of them are signaled already, we
still keep one of them. So instead of using add_fence(), which will not
increase the refcount of signaled fences, we should explicitly call
fence_get() for the fence we are keeping.

This patch fixes a kernel panic that can be triggered by creating a fence
that is expired (or increasing the timeline until it expires), then
creating a merged fence out of it, and deleting the merged fence. This
will make the original expired fence's refcount go to zero.

Testcase: igt/sw_sync/sync_expired_merge
Signed-off-by: Rafael Antognolli 
Reviewed-by: Chris Wilson 
Reviewed-by: Gustavo Padovan 
Signed-off-by: Sumit Semwal 
Link: http://patchwork.freedesktop.org/patch/msgid/1473966865-4508-1-git-send-email-rafael.antognolli@intel.com

dma-buf/sync-file: Avoid enable fence signaling if poll(.timeout=0)

2016-09-13T14:39:49+00:00

If we being polled with a timeout of zero, a nonblocking busy query,
we don't need to install any fence callbacks as we will not be waiting.
As we only install the callback once, the overhead comes from the atomic
bit test that also causes serialisation between threads.

Signed-off-by: Chris Wilson 
Cc: Sumit Semwal 
Cc: Gustavo Padovan 
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Reviewed-by: Gustavo Padovan 
Signed-off-by: Sumit Semwal 
Link: http://patchwork.freedesktop.org/patch/msgid/20160829181613.30722-1-chris@chris-wilson.co.uk

dma-buf/sync_file: only enable fence signalling on poll()

2016-08-11T10:09:38+00:00

Signalling doesn't need to be enabled at sync_file creation, it is only
required if userspace waiting the fence to signal through poll().

Thus we delay fence_add_callback() until poll is called. It only adds the
callback the first time poll() is called. This avoid re-adding the same
callback multiple times.

v2: rebase and update to work with new fence support for sync_file

v3: use atomic operation to set enabled and protect fence_add_callback()

v4: use user bit from fence flags (comment from Chris Wilson)

v5: use ternary if on poll return (comment from Chris Wilson)

Signed-off-by: Gustavo Padovan 
Reviewed-by: Chris Wilson 
Signed-off-by: Sumit Semwal 
  [sumits: remove unused var status]
Link: http://patchwork.freedesktop.org/patch/msgid/1470404378-27961-1-git-send-email-gustavo@padovan.org

dma-buf/sync_file: add sync_file_get_fence()

2016-08-11T10:03:24+00:00

Creates a function that given an sync file descriptor returns a
fence containing all fences in the sync_file.

v2: Comments by Daniel Vetter
	- Adapt to new version of fence_collection_init()
	- Hold a reference for the fence we return

v3:
	- Adapt to use fput() directly
	- rename to sync_file_get_fence() as we always return one fence

v4: Adapt to use fence_array

v5: set fence through fence_get()

Signed-off-by: Gustavo Padovan 
Reviewed-by: Chris Wilson 
Acked-by: Christian König 
Signed-off-by: Sumit Semwal

dma-buf/sync_file: refactor fence storage in struct sync_file

2016-08-11T10:03:24+00:00

Create sync_file->fence to abstract the type of fence we are using for
each sync_file. If only one fence is present we use a normal struct fence
but if there is more fences to be added to the sync_file a fence_array
is created.

This change cleans up sync_file a bit. We don't need to have sync_file_cb
array anymore. Instead, as we always have  one fence, only one fence
callback is registered per sync_file.

v2: Comments from Chris Wilson and Christian König
	- Not using fence_ops anymore
	- fence_is_array() was created to differentiate fence from fence_array
	- fence_array_teardown() is now exported and used under fence_is_array()
	- struct sync_file lost num_fences member

v3: Comments from Chris Wilson and Christian König
	- struct sync_file lost status member in favor of fence_is_signaled()
	- drop use of fence_array_teardown()
	- use sizeof(*fence) to allocate only an array on fence pointers

v4: Comments from Chris Wilson
	- use sizeof(*fence) to reallocate array
	- fix typo in comments
	- protect num_fences sum against overflows
	- use array->base instead of casting the to struct fence

v5: fixes checkpatch warnings

v6: fix case where all fences are signaled.

Signed-off-by: Gustavo Padovan 
Reviewed-by: Chris Wilson 
Acked-by: Christian König 
Acked-by: Greg Kroah-Hartman 
Signed-off-by: Sumit Semwal