[PARISC] Arch-specific compat signals

Add enough arch-specific compat signals code to enable parisc64
to compile and boot out of the mainline tree. There are likely still
many dragons here, but this is a start to squashing the last
big difference between the mainline tree and the parisc-linux tree.
The remaining bugs can be squashed as they come up.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>

1 files changed, 125 insertions, 2 deletions

diff --git a/arch/parisc/kernel/signal32.h b/arch/parisc/kernel/signal32.h
index 4d1569e717cc..e39b38a67a87 100644
--- a/arch/parisc/kernel/signal32.h
+++ b/arch/parisc/kernel/signal32.h
@@ -20,8 +20,34 @@
 #define _PARISC64_KERNEL_SIGNAL32_H
 
 #include <linux/compat.h>
-#include <asm/compat_signal.h>
-#include <asm/compat_rt_sigframe.h>
+
+typedef compat_uptr_t compat_sighandler_t;
+
+typedef struct compat_sigaltstack {
+        compat_uptr_t ss_sp;
+        compat_int_t ss_flags;
+        compat_size_t ss_size;
+} compat_stack_t;
+
+/* Most things should be clean enough to redefine this at will, if care
+   is taken to make libc match.  */
+
+struct compat_sigaction {
+        compat_sighandler_t sa_handler;
+        compat_uint_t sa_flags;
+        compat_sigset_t sa_mask;               /* mask last for extensibility */
+};
+
+/* 32-bit ucontext as seen from an 64-bit kernel */
+struct compat_ucontext {
+        compat_uint_t uc_flags;
+        compat_uptr_t uc_link;
+        compat_stack_t uc_stack;        /* struct compat_sigaltstack (12 bytes)*/
+        /* FIXME: Pad out to get uc_mcontext to start at an 8-byte aligned boundary */
+        compat_uint_t pad[1];
+        struct compat_sigcontext uc_mcontext;
+        compat_sigset_t uc_sigmask;     /* mask last for extensibility */
+};
 
 /* ELF32 signal handling */
 
@@ -29,6 +55,103 @@ struct k_sigaction32 {
         struct compat_sigaction sa;
 };
 
+typedef struct compat_siginfo {
+        int si_signo;
+        int si_errno;
+        int si_code;
+
+        union {
+                int _pad[((128/sizeof(int)) - 3)];
+
+                /* kill() */
+                struct {
+                        unsigned int _pid;      /* sender's pid */
+                        unsigned int _uid;      /* sender's uid */
+                } _kill;
+
+                /* POSIX.1b timers */
+                struct {
+                        compat_timer_t _tid;            /* timer id */
+                        int _overrun;           /* overrun count */
+                        char _pad[sizeof(unsigned int) - sizeof(int)];
+                        compat_sigval_t _sigval;        /* same as below */
+                        int _sys_private;       /* not to be passed to user */
+                } _timer;
+
+                /* POSIX.1b signals */
+                struct {
+                        unsigned int _pid;      /* sender's pid */
+                        unsigned int _uid;      /* sender's uid */
+                        compat_sigval_t _sigval;
+                } _rt;
+
+                /* SIGCHLD */
+                struct {
+                        unsigned int _pid;      /* which child */
+                        unsigned int _uid;      /* sender's uid */
+                        int _status;            /* exit code */
+                        compat_clock_t _utime;
+                        compat_clock_t _stime;
+                } _sigchld;
+
+                /* SIGILL, SIGFPE, SIGSEGV, SIGBUS */
+                struct {
+                        unsigned int _addr;     /* faulting insn/memory ref. */
+                } _sigfault;
+
+                /* SIGPOLL */
+                struct {
+                        int _band;      /* POLL_IN, POLL_OUT, POLL_MSG */
+                        int _fd;
+                } _sigpoll;
+        } _sifields;
+} compat_siginfo_t;
+
+int copy_siginfo_to_user32 (compat_siginfo_t __user *to, siginfo_t *from);
+int copy_siginfo_from_user32 (siginfo_t *to, compat_siginfo_t __user *from);
+
+/* 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)
+
 void sigset_32to64(sigset_t *s64, compat_sigset_t *s32);
 void sigset_64to32(compat_sigset_t *s32, sigset_t *s64);
 int do_sigaltstack32 (const compat_stack_t __user *uss32,