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compat_rt_sigframe.h
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1 #include <linux/compat.h>
2 #include <linux/compat_siginfo.h>
3 #include <asm/compat_ucontext.h>
4 
5 #ifndef _ASM_PARISC_COMPAT_RT_SIGFRAME_H
6 #define _ASM_PARISC_COMPAT_RT_SIGFRAME_H
7 
8 /* In a deft move of uber-hackery, we decide to carry the top half of all
9  * 64-bit registers in a non-portable, non-ABI, hidden structure.
10  * Userspace can read the hidden structure if it *wants* but is never
11  * guaranteed to be in the same place. Infact the uc_sigmask from the
12  * ucontext_t structure may push the hidden register file downards
13  */
15  /* Upper half of all the 64-bit registers that were truncated
16  on a copy to a 32-bit userspace */
21 };
22 
23 #define COMPAT_SIGRETURN_TRAMP 4
24 #define COMPAT_SIGRESTARTBLOCK_TRAMP 5
25 #define COMPAT_TRAMP_SIZE (COMPAT_SIGRETURN_TRAMP + COMPAT_SIGRESTARTBLOCK_TRAMP)
26 
27 struct compat_rt_sigframe {
28  /* XXX: Must match trampoline size in arch/parisc/kernel/signal.c
29  Secondary to that it must protect the ERESTART_RESTARTBLOCK
30  trampoline we left on the stack (we were bad and didn't
31  change sp so we could run really fast.) */
35  /* Hidden location of truncated registers, *must* be last. */
37 };
38 
39 /*
40  * The 32-bit ABI wants at least 48 bytes for a function call frame:
41  * 16 bytes for arg0-arg3, and 32 bytes for magic (the only part of
42  * which Linux/parisc uses is sp-20 for the saved return pointer...)
43  * Then, the stack pointer must be rounded to a cache line (64 bytes).
44  */
45 #define SIGFRAME32 64
46 #define FUNCTIONCALLFRAME32 48
47 #define PARISC_RT_SIGFRAME_SIZE32 \
48  (((sizeof(struct compat_rt_sigframe) + FUNCTIONCALLFRAME32) + SIGFRAME32) & -SIGFRAME32)
49 
50 #endif