[PATCH 2/2] dma-buf/sync-file: fix warning about fence containers
Christian König
ckoenig.leichtzumerken at gmail.com
Fri Mar 11 11:02:44 UTC 2022
The dma_fence_chain containers can show up in sync_files as well resulting in
warnings that those can't be added to dma_fence_array containers when merging
multiple sync_files together.
Solve this by using the dma_fence_unwrap iterator to deep dive into the
contained fences and then add those flatten out into a dma_fence_array.
Signed-off-by: Christian König <christian.koenig at amd.com>
---
drivers/dma-buf/sync_file.c | 141 +++++++++++++++++++-----------------
1 file changed, 73 insertions(+), 68 deletions(-)
diff --git a/drivers/dma-buf/sync_file.c b/drivers/dma-buf/sync_file.c
index 394e6e1e9686..b8dea4ec123b 100644
--- a/drivers/dma-buf/sync_file.c
+++ b/drivers/dma-buf/sync_file.c
@@ -5,6 +5,7 @@
* Copyright (C) 2012 Google, Inc.
*/
+#include <linux/dma-fence-unwrap.h>
#include <linux/export.h>
#include <linux/file.h>
#include <linux/fs.h>
@@ -172,20 +173,6 @@ static int sync_file_set_fence(struct sync_file *sync_file,
return 0;
}
-static struct dma_fence **get_fences(struct sync_file *sync_file,
- int *num_fences)
-{
- if (dma_fence_is_array(sync_file->fence)) {
- struct dma_fence_array *array = to_dma_fence_array(sync_file->fence);
-
- *num_fences = array->num_fences;
- return array->fences;
- }
-
- *num_fences = 1;
- return &sync_file->fence;
-}
-
static void add_fence(struct dma_fence **fences,
int *i, struct dma_fence *fence)
{
@@ -210,86 +197,97 @@ static void add_fence(struct dma_fence **fences,
static struct sync_file *sync_file_merge(const char *name, struct sync_file *a,
struct sync_file *b)
{
+ struct dma_fence *a_fence, *b_fence, **fences;
+ struct dma_fence_unwrap a_iter, b_iter;
+ unsigned int index, num_fences;
struct sync_file *sync_file;
- struct dma_fence **fences = NULL, **nfences, **a_fences, **b_fences;
- int i = 0, i_a, i_b, num_fences, a_num_fences, b_num_fences;
sync_file = sync_file_alloc();
if (!sync_file)
return NULL;
- a_fences = get_fences(a, &a_num_fences);
- b_fences = get_fences(b, &b_num_fences);
- if (a_num_fences > INT_MAX - b_num_fences)
- goto err;
+ num_fences = 0;
+ dma_fence_unwrap_for_each(a_fence, &a_iter, a->fence)
+ ++num_fences;
+ dma_fence_unwrap_for_each(b_fence, &b_iter, b->fence)
+ ++num_fences;
- num_fences = a_num_fences + b_num_fences;
+ if (num_fences > INT_MAX)
+ goto err_free_sync_file;
fences = kcalloc(num_fences, sizeof(*fences), GFP_KERNEL);
if (!fences)
- goto err;
+ goto err_free_sync_file;
/*
- * Assume sync_file a and b are both ordered and have no
- * duplicates with the same context.
+ * We can't guarantee that fences in both a and b are ordered, but it is
+ * still quite likely.
*
- * If a sync_file can only be created with sync_file_merge
- * and sync_file_create, this is a reasonable assumption.
+ * So attempt to order the fences as we pass over them and merge fences
+ * with the same context.
*/
- for (i_a = i_b = 0; i_a < a_num_fences && i_b < b_num_fences; ) {
- struct dma_fence *pt_a = a_fences[i_a];
- struct dma_fence *pt_b = b_fences[i_b];
- if (pt_a->context < pt_b->context) {
- add_fence(fences, &i, pt_a);
+ index = 0;
+ for (a_fence = dma_fence_unwrap_first(a->fence, &a_iter),
+ b_fence = dma_fence_unwrap_first(b->fence, &b_iter);
+ a_fence || b_fence; ) {
+
+ if (!b_fence) {
+ add_fence(fences, &index, a_fence);
+ a_fence = dma_fence_unwrap_next(&a_iter);
+
+ } else if (!a_fence) {
+ add_fence(fences, &index, b_fence);
+ b_fence = dma_fence_unwrap_next(&b_iter);
+
+ } else if (a_fence->context < b_fence->context) {
+ add_fence(fences, &index, a_fence);
+ a_fence = dma_fence_unwrap_next(&a_iter);
- i_a++;
- } else if (pt_a->context > pt_b->context) {
- add_fence(fences, &i, pt_b);
+ } else if (b_fence->context < a_fence->context) {
+ add_fence(fences, &index, b_fence);
+ b_fence = dma_fence_unwrap_next(&b_iter);
+
+ } else if (__dma_fence_is_later(a_fence->seqno, b_fence->seqno,
+ a_fence->ops)) {
+ add_fence(fences, &index, a_fence);
+ a_fence = dma_fence_unwrap_next(&a_iter);
+ b_fence = dma_fence_unwrap_next(&b_iter);
- i_b++;
} else {
- if (__dma_fence_is_later(pt_a->seqno, pt_b->seqno,
- pt_a->ops))
- add_fence(fences, &i, pt_a);
- else
- add_fence(fences, &i, pt_b);
-
- i_a++;
- i_b++;
+ add_fence(fences, &index, b_fence);
+ a_fence = dma_fence_unwrap_next(&a_iter);
+ b_fence = dma_fence_unwrap_next(&b_iter);
}
}
- for (; i_a < a_num_fences; i_a++)
- add_fence(fences, &i, a_fences[i_a]);
-
- for (; i_b < b_num_fences; i_b++)
- add_fence(fences, &i, b_fences[i_b]);
-
- if (i == 0)
- fences[i++] = dma_fence_get(a_fences[0]);
+ if (index == 0)
+ add_fence(fences, &index, dma_fence_get_stub());
- if (num_fences > i) {
- nfences = krealloc_array(fences, i, sizeof(*fences), GFP_KERNEL);
- if (!nfences)
- goto err;
+ if (num_fences > index) {
+ struct dma_fence **tmp;
- fences = nfences;
+ /* Keep going even when reducing the size failed */
+ tmp = krealloc_array(fences, index, sizeof(*fences),
+ GFP_KERNEL);
+ if (tmp)
+ fences = tmp;
}
- if (sync_file_set_fence(sync_file, fences, i) < 0)
- goto err;
+ if (sync_file_set_fence(sync_file, fences, index) < 0)
+ goto err_put_fences;
strlcpy(sync_file->user_name, name, sizeof(sync_file->user_name));
return sync_file;
-err:
- while (i)
- dma_fence_put(fences[--i]);
+err_put_fences:
+ while (index)
+ dma_fence_put(fences[--index]);
kfree(fences);
+
+err_free_sync_file:
fput(sync_file->file);
return NULL;
-
}
static int sync_file_release(struct inode *inode, struct file *file)
@@ -398,11 +396,13 @@ static int sync_fill_fence_info(struct dma_fence *fence,
static long sync_file_ioctl_fence_info(struct sync_file *sync_file,
unsigned long arg)
{
- struct sync_file_info info;
struct sync_fence_info *fence_info = NULL;
- struct dma_fence **fences;
+ struct dma_fence_unwrap iter;
+ struct sync_file_info info;
+ unsigned int num_fences;
+ struct dma_fence *fence;
+ int ret;
__u32 size;
- int num_fences, ret, i;
if (copy_from_user(&info, (void __user *)arg, sizeof(info)))
return -EFAULT;
@@ -410,7 +410,9 @@ static long sync_file_ioctl_fence_info(struct sync_file *sync_file,
if (info.flags || info.pad)
return -EINVAL;
- fences = get_fences(sync_file, &num_fences);
+ num_fences = 0;
+ dma_fence_unwrap_for_each(fence, &iter, sync_file->fence)
+ ++num_fences;
/*
* Passing num_fences = 0 means that userspace doesn't want to
@@ -433,8 +435,11 @@ static long sync_file_ioctl_fence_info(struct sync_file *sync_file,
if (!fence_info)
return -ENOMEM;
- for (i = 0; i < num_fences; i++) {
- int status = sync_fill_fence_info(fences[i], &fence_info[i]);
+ num_fences = 0;
+ dma_fence_unwrap_for_each(fence, &iter, sync_file->fence) {
+ int status;
+
+ status = sync_fill_fence_info(fence, &fence_info[num_fences++]);
info.status = info.status <= 0 ? info.status : status;
}
--
2.25.1
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