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author | Christian König <christian.koenig@amd.com> | 2021-11-03 10:02:08 +0100 |
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committer | Christian König <christian.koenig@amd.com> | 2022-04-03 17:53:28 +0200 |
commit | 92cedee6a6a3e6fcc3ffc0e3866baae5f6f76ac1 (patch) | |
tree | ec31e50f6de3b5ebaaf8c17aa9e311dad3dcbb7e /drivers/dma-buf | |
parent | d791aec9ff43df4ea0a6690eabd6c395e982ef6f (diff) | |
download | linux-92cedee6a6a3e6fcc3ffc0e3866baae5f6f76ac1.tar.gz linux-92cedee6a6a3e6fcc3ffc0e3866baae5f6f76ac1.tar.bz2 linux-92cedee6a6a3e6fcc3ffc0e3866baae5f6f76ac1.zip |
dma-buf: add dma_resv_get_singleton v2
Add a function to simplify getting a single fence for all the fences in
the dma_resv object.
v2: fix ref leak in error handling
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220321135856.1331-3-christian.koenig@amd.com
Diffstat (limited to 'drivers/dma-buf')
-rw-r--r-- | drivers/dma-buf/dma-resv.c | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index be65522f0f47..ff16da0a54ec 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -34,6 +34,7 @@ */ #include <linux/dma-resv.h> +#include <linux/dma-fence-array.h> #include <linux/export.h> #include <linux/mm.h> #include <linux/sched/mm.h> @@ -637,6 +638,59 @@ int dma_resv_get_fences(struct dma_resv *obj, bool write, EXPORT_SYMBOL_GPL(dma_resv_get_fences); /** + * dma_resv_get_singleton - Get a single fence for all the fences + * @obj: the reservation object + * @write: true if we should return all fences + * @fence: the resulting fence + * + * Get a single fence representing all the fences inside the resv object. + * Returns either 0 for success or -ENOMEM. + * + * Warning: This can't be used like this when adding the fence back to the resv + * object since that can lead to stack corruption when finalizing the + * dma_fence_array. + * + * Returns 0 on success and negative error values on failure. + */ +int dma_resv_get_singleton(struct dma_resv *obj, bool write, + struct dma_fence **fence) +{ + struct dma_fence_array *array; + struct dma_fence **fences; + unsigned count; + int r; + + r = dma_resv_get_fences(obj, write, &count, &fences); + if (r) + return r; + + if (count == 0) { + *fence = NULL; + return 0; + } + + if (count == 1) { + *fence = fences[0]; + kfree(fences); + return 0; + } + + array = dma_fence_array_create(count, fences, + dma_fence_context_alloc(1), + 1, false); + if (!array) { + while (count--) + dma_fence_put(fences[count]); + kfree(fences); + return -ENOMEM; + } + + *fence = &array->base; + return 0; +} +EXPORT_SYMBOL_GPL(dma_resv_get_singleton); + +/** * dma_resv_wait_timeout - Wait on reservation's objects * shared and/or exclusive fences. * @obj: the reservation object |