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Diffstat (limited to 'include/asm-parisc/compat_rt_sigframe.h')
-rw-r--r--include/asm-parisc/compat_rt_sigframe.h50
1 files changed, 50 insertions, 0 deletions
diff --git a/include/asm-parisc/compat_rt_sigframe.h b/include/asm-parisc/compat_rt_sigframe.h
new file mode 100644
index 000000000000..81bec28bdc48
--- /dev/null
+++ b/include/asm-parisc/compat_rt_sigframe.h
@@ -0,0 +1,50 @@
+#include<linux/compat.h>
+#include<linux/compat_siginfo.h>
+#include<asm/compat_ucontext.h>
+
+#ifndef _ASM_PARISC_COMPAT_RT_SIGFRAME_H
+#define _ASM_PARISC_COMPAT_RT_SIGFRAME_H
+
+/* In a deft move of uber-hackery, we decide to carry the top half of all
+ * 64-bit registers in a non-portable, non-ABI, hidden structure.
+ * Userspace can read the hidden structure if it *wants* but is never
+ * guaranteed to be in the same place. Infact the uc_sigmask from the
+ * ucontext_t structure may push the hidden register file downards
+ */
+struct compat_regfile {
+ /* Upper half of all the 64-bit registers that were truncated
+ on a copy to a 32-bit userspace */
+ compat_int_t rf_gr[32];
+ compat_int_t rf_iasq[2];
+ compat_int_t rf_iaoq[2];
+ compat_int_t rf_sar;
+};
+
+#define COMPAT_SIGRETURN_TRAMP 4
+#define COMPAT_SIGRESTARTBLOCK_TRAMP 5
+#define COMPAT_TRAMP_SIZE (COMPAT_SIGRETURN_TRAMP + COMPAT_SIGRESTARTBLOCK_TRAMP)
+
+struct compat_rt_sigframe {
+ /* XXX: Must match trampoline size in arch/parisc/kernel/signal.c
+ Secondary to that it must protect the ERESTART_RESTARTBLOCK
+ trampoline we left on the stack (we were bad and didn't
+ change sp so we could run really fast.) */
+ compat_uint_t tramp[COMPAT_TRAMP_SIZE];
+ compat_siginfo_t info;
+ struct compat_ucontext uc;
+ /* Hidden location of truncated registers, *must* be last. */
+ struct compat_regfile regs;
+};
+
+/*
+ * The 32-bit ABI wants at least 48 bytes for a function call frame:
+ * 16 bytes for arg0-arg3, and 32 bytes for magic (the only part of
+ * which Linux/parisc uses is sp-20 for the saved return pointer...)
+ * Then, the stack pointer must be rounded to a cache line (64 bytes).
+ */
+#define SIGFRAME32 64
+#define FUNCTIONCALLFRAME32 48
+#define PARISC_RT_SIGFRAME_SIZE32 \
+ (((sizeof(struct compat_rt_sigframe) + FUNCTIONCALLFRAME32) + SIGFRAME32) & -SIGFRAME32)
+
+#endif