diff options
| author | Flavio Cruz <flaviocruz@gmail.com> | 2023-02-12 18:54:58 -0500 |
|---|---|---|
| committer | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2023-02-13 01:00:32 +0100 |
| commit | ea2646b6d6f2dc02a59a2693d08957596c84e9d3 (patch) | |
| tree | 7a6c0e61eec61c4b7231fd2f35ff6c226b53b5c5 /include | |
| parent | 7170cfbfb70cdce12ea6ec6697ed95c557aa1989 (diff) | |
Make mach_msg_header_t have the same size for both 64 bit kernel and userland.
This has several advantages:
1) We don't need to resize mach_msg_header_t, it is just a copy.
2) Mig won't require any changes because it statically computes the size
of mach_msg_header_t, otherwise we would need two sizes (28 vs 32 bytes).
Message-Id: <Y+l8UhXXX9Qo9tVA@jupiter.tail36e24.ts.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/mach/message.h | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/include/mach/message.h b/include/mach/message.h index 63341e6f..eb3b34c0 100644 --- a/include/mach/message.h +++ b/include/mach/message.h @@ -139,7 +139,15 @@ typedef integer_t mach_msg_id_t; typedef struct mach_msg_header { mach_msg_bits_t msgh_bits; mach_msg_size_t msgh_size; - mach_port_t msgh_remote_port; + union { + mach_port_t msgh_remote_port; + /* + * Ensure msgh_remote_port is wide enough to hold a kernel pointer + * to avoid message resizing for the 64 bits case. This field should + * not be used since it is here just for padding purposes. + */ + rpc_uintptr_t msgh_remote_port_do_not_use; + }; union { mach_port_t msgh_local_port; rpc_uintptr_t msgh_protected_payload; @@ -153,7 +161,10 @@ typedef struct mach_msg_header { typedef struct { mach_msg_bits_t msgh_bits; mach_msg_size_t msgh_size; - mach_port_name_t msgh_remote_port; + union { + mach_port_name_t msgh_remote_port; + rpc_uintptr_t msgh_remote_port_do_not_use; + }; union { mach_port_name_t msgh_local_port; rpc_uintptr_t msgh_protected_payload; |