1 Parameter Info Block (PIB)
3 buffer_size 32-bit Size of the destination buffer, excluding
6 The total number of bytes in all of the segments that require a
7 buffer to be created in the destination address space, with each
8 buffer individually rounded up to an 8-byte alignment. This is
9 specified so that the kernel can allocate one large buffer for all
10 segments before traversing the segment list. When returning from
11 a method, the buffer size only includes buffers allocated by the
12 caller; "inout" segments where the caller specified a non-NULL
13 ptr, and the callee did not increase the length, are not included
14 (because the kernel does not need to allocate a caller-side buffer
15 for them). The kernel may throw an exception if the actual size
16 is greater than specified in this field.
18 This only covers the "normal" segments which are mapped only
19 for the duration of the call. Copy segments are handled
22 copy_size 32-bit Size of all Copy segments.
24 This is like buffer_size, but for Copy segments.
26 objlist_ptr pointer Pointer to the object list
27 objlist_len 32-bit Length of the object list, in IDs
29 The object list is a special segment that contains object IDs
30 rather than arbitrary data. Each object ID will be translated
31 into the destination ID-space, allocating new IDs when
32 necessary. The IDs themselves are 32 bits each, unsigned,
33 regardless of the pointer size. The first object in the list
34 is the object to receive the message.
36 num_segments 32-bit Number of data segments
38 segment.ptr pointer Pointer to data segment
39 segment.len 32-bit Length of data segment in bytes
40 segment.flags 32-bit Attributes of data segment
41 reserved Reserved for future use, and for
42 power-of-two indexing -- pad to
45 Each segment describes data being transmitted to and/or from the
46 callee. For out segments, the caller may designate a buffer to hold
47 the data, or it may leave the ptr field NULL. The caller may
48 replace an out segment pointer with its own (it must do this if it
49 was NULL), and it may change the length of the segment. Except when
50 flags such as Push or Shared force the kernel to map, rather than
51 copy, the data, it will choose which method to use based on the
52 size, page-alignment, and overmap status of the segment.
54 Segment Flags (see doc/orb/memory-management for more details):
55 In 0x01 Data is copied/mapped from caller to callee.
56 Out 0x02 Data is copied/mapped from callee to caller.
57 The data is unmapped from the callee unless
59 Inline 0x04 The callee cannot change the length of an
60 Out segment, and the caller must provide the
61 buffer. Ignored for In segments.
62 Copy 0x08 The segment is permanently copied into the
63 destination address space, with read/write