flat_binder_object is used for both handling binder objects and file descriptors, even though the two are mostly independent. Since we'll have more fixup objects in binder in the future, instead of extending flat_binder_object again, split out file descriptors to their own object while retaining backwards compatibility to existing user-space clients. All binder objects just share a header.
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| @@ -48,6 +48,14 @@ typedef __u64 binder_size_t; · 47 unmodified lines | ||
| 48 | 48 | typedef __u64 binder_uintptr_t; |
| 49 | 49 | #endif |
| 50 | 50 | |
| 51 | +/** | |
| 52 | + * struct binder_object_header - header shared by all binder metadata objects. | |
| 53 | + * @type: type of the object | |
| 54 | + */ | |
| 55 | +struct binder_object_header { | |
| 56 | + __u32 type; | |
| 57 | +}; | |
| 58 | + | |
| 51 | 59 | /* |
| 52 | 60 | * This is the flattened representation of a Binder object for transfer |
| 53 | 61 | * between processes. The 'offsets' supplied as part of a binder transaction |
| @@ -56,9 +64,8 @@ typedef __u64 binder_uintptr_t; · 2 unmodified lines | ||
| 56 | 64 | * between processes. |
| 57 | 65 | */ |
| 58 | 66 | struct flat_binder_object { |
| 59 | − /* 8 bytes for large_flat_header. */ | |
| 60 | − __u32 type; | |
| 61 | − __u32 flags; | |
| 67 | + struct binder_object_header hdr; | |
| 68 | + __u32 flags; | |
| 62 | 69 | |
| 63 | 70 | /* 8 bytes of data. */ |
| 64 | 71 | union { |
| @@ -70,6 +77,24 @@ struct flat_binder_object { · 5 unmodified lines | ||
| 70 | 77 | binder_uintptr_t cookie; |
| 71 | 78 | }; |
| 72 | 79 | |
| 80 | +/** | |
| 81 | + * struct binder_fd_object - describes a filedescriptor to be fixed up. | |
| 82 | + * @hdr: common header structure | |
| 83 | + * @pad_flags: padding to remain compatible with old userspace code | |
| 84 | + * @pad_binder: padding to remain compatible with old userspace code | |
| 85 | + * @fd: file descriptor | |
| 86 | + * @cookie: opaque data, used by user-space | |
| 87 | + */ | |
| 88 | +struct binder_fd_object { | |
| 89 | + struct binder_object_header hdr; | |
| 90 | + __u32 pad_flags; | |
| 91 | + union { | |
| 92 | + binder_uintptr_t pad_binder; | |
| 93 | + __u32 fd; | |
| 94 | + }; | |
| 95 | + | |
| 96 | + binder_uintptr_t cookie; | |
| 97 | +}; | |
| 73 | 98 | /* |
| 74 | 99 | * On 64-bit platforms where user code may run in 32-bits the driver must |
| 75 | 100 | * translate the buffer (and local binder) addresses appropriately. |