Op 03-02-16 om 14:25 schreef Gustavo Padovan:
From: Gustavo Padovan gustavo.padovan@collabora.co.uk
Turn sync_fence_info into __u64 type enable us to extend the struct in the future without breaking the ABI.
v2: use type __u64 for fence_info
v3: fix commit message to reflect the v2 change
Signed-off-by: Gustavo Padovan gustavo.padovan@collabora.co.uk
drivers/staging/android/sync.c | 2 +- drivers/staging/android/uapi/sync.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c index 2ab0c20..8425457 100644 --- a/drivers/staging/android/sync.c +++ b/drivers/staging/android/sync.c @@ -525,7 +525,7 @@ static long sync_file_ioctl_fence_info(struct sync_file *sync_file, if (info->status >= 0) info->status = !info->status;
- len = sizeof(struct sync_file_info);
len = sizeof(struct sync_file_info) - sizeof(__u64);
for (i = 0; i < sync_file->num_fences; ++i) { struct fence *fence = sync_file->cbs[i].fence;
diff --git a/drivers/staging/android/uapi/sync.h b/drivers/staging/android/uapi/sync.h index a0cf357..e649953 100644 --- a/drivers/staging/android/uapi/sync.h +++ b/drivers/staging/android/uapi/sync.h @@ -54,7 +54,7 @@ struct sync_file_info { char name[32]; __s32 status;
- __u8 sync_fence_info[0];
- __u64 sync_fence_info;
};
#define SYNC_IOC_MAGIC '>'
This still doesn't do what you expect it to.
I think this is what you want is for userspace to do:
struct sync_file_info info;
info.flags = info.num_fences = 0; ioctl(fd, SYNC_IOC_FENCE_INFO, &info); if (info.num_fences) { info.sync_fence_info = (uintptr)kcalloc(info.num_fences, sizeof(struct sync_fence_info)); ioctl(fd, SYNC_IOC_FENCE_INFO, &info); }
Maybe userspace could preallocate the max in advance and set num_fences higher,
kernel would do something like:
num_fences = min(info.num_fences, sync->num_fences); struct sync_fence_info array[num_fences];
info.num_fences = sync->num_fences; if (num_fences && copy_to_user((void * __user)(unsigned long)info.sync_fence_info, array, num_fences * sizeof(array))) return -EFAULT;