1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /*
3 * DMABUF Heaps Userspace API
4 *
5 * Copyright (C) 2011 Google, Inc.
6 * Copyright (C) 2019 Linaro Ltd.
7 */
8 #ifndef _UAPI_LINUX_DMABUF_POOL_H
9 #define _UAPI_LINUX_DMABUF_POOL_H
10
11 #include <linux/ioctl.h>
12 #include <linux/types.h>
13
14 /**
15 * DOC: DMABUF Heaps Userspace API
16 */
17
18 /* Valid FD_FLAGS are O_CLOEXEC, O_RDONLY, O_WRONLY, O_RDWR */
19 #define DMA_HEAP_VALID_FD_FLAGS (O_CLOEXEC | O_ACCMODE)
20
21 /* Currently no heap flags */
22 #define DMA_HEAP_VALID_HEAP_FLAGS (0)
23
24 /**
25 * struct dma_heap_allocation_data - metadata passed from userspace for
26 * allocations
27 * @len: size of the allocation
28 * @fd: will be populated with a fd which provides the
29 * handle to the allocated dma-buf
30 * @fd_flags: file descriptor flags used when allocating
31 * @heap_flags: flags passed to heap
32 *
33 * Provided by userspace as an argument to the ioctl
34 */
35 struct dma_heap_allocation_data {
36 __u64 len;
37 __u32 fd;
38 __u32 fd_flags;
39 __u64 heap_flags;
40 };
41
42 #define DMA_HEAP_IOC_MAGIC 'H'
43
44 enum dma_heap_flag_owner_id {
45 OWNER_DEFAULT = 0,
46 OWNER_GPU,
47 OWNER_MEDIA_CODEC,
48 COUNT_DMA_HEAP_FLAG_OWNER,
49 };
50
51 #define OWNER_OFFSET_BIT 27 /* 27 bit */
52 #define OWNER_MASK (0xfUL << OWNER_OFFSET_BIT)
53
54 /* Use the 27-30 bits of heap flags as owner_id flag */
set_owner_id_for_heap_flags(__u64 * heap_flags,__u64 owner_id)55 static inline void set_owner_id_for_heap_flags(__u64 *heap_flags, __u64 owner_id)
56 {
57 if (heap_flags == NULL || owner_id >= COUNT_DMA_HEAP_FLAG_OWNER) {
58 return;
59 }
60 *heap_flags |= owner_id << OWNER_OFFSET_BIT;
61 }
62
63 /* To get the binary number of owner_id */
get_owner_id_from_heap_flags(__u64 heap_flags)64 static inline __u64 get_owner_id_from_heap_flags(__u64 heap_flags)
65 {
66 return (heap_flags & OWNER_MASK) >> OWNER_OFFSET_BIT;
67 }
68
69 /**
70 * DOC: DMA_HEAP_IOCTL_ALLOC - allocate memory from pool
71 *
72 * Takes a dma_heap_allocation_data struct and returns it with the fd field
73 * populated with the dmabuf handle of the allocation.
74 */
75 #define DMA_HEAP_IOCTL_ALLOC _IOWR(DMA_HEAP_IOC_MAGIC, 0x0,\
76 struct dma_heap_allocation_data)
77
78 #endif /* _UAPI_LINUX_DMABUF_POOL_H */
79