[S390] 64-bit register support for 31-bit processes

From: Heiko Carstens <heiko.carstens@de.ibm.com>
From: Martin Schwidefsky <schwidefsky@de.ibm.com>

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 34 insertions, 1 deletions

diff --git a/arch/s390/kernel/compat_signal.c b/arch/s390/kernel/compat_signal.c
index b537cb0e9b55..eee999853a7c 100644
--- a/arch/s390/kernel/compat_signal.c
+++ b/arch/s390/kernel/compat_signal.c
@@ -39,6 +39,7 @@ typedef struct
         struct sigcontext32 sc;
         _sigregs32 sregs;
         int signo;
+        __u32 gprs_high[NUM_GPRS];
         __u8 retcode[S390_SYSCALL_SIZE];
 } sigframe32;
 
@@ -48,6 +49,7 @@ typedef struct
         __u8 retcode[S390_SYSCALL_SIZE];
         compat_siginfo_t info;
         struct ucontext32 uc;
+        __u32 gprs_high[NUM_GPRS];
 } rt_sigframe32;
 
 int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from)
@@ -344,6 +346,30 @@ static int restore_sigregs32(struct pt_regs *regs,_sigregs32 __user *sregs)
         return 0;
 }
 
+static int save_sigregs_gprs_high(struct pt_regs *regs, __u32 __user *uregs)
+{
+        __u32 gprs_high[NUM_GPRS];
+        int i;
+
+        for (i = 0; i < NUM_GPRS; i++)
+                gprs_high[i] = regs->gprs[i] >> 32;
+
+        return __copy_to_user(uregs, &gprs_high, sizeof(gprs_high));
+}
+
+static int restore_sigregs_gprs_high(struct pt_regs *regs, __u32 __user *uregs)
+{
+        __u32 gprs_high[NUM_GPRS];
+        int err, i;
+
+        err = __copy_from_user(&gprs_high, uregs, sizeof(gprs_high));
+        if (err)
+                return err;
+        for (i = 0; i < NUM_GPRS; i++)
+                *(__u32 *)&regs->gprs[i] = gprs_high[i];
+        return 0;
+}
+
 asmlinkage long sys32_sigreturn(void)
 {
         struct pt_regs *regs = task_pt_regs(current);
@@ -363,6 +389,8 @@ asmlinkage long sys32_sigreturn(void)
 
         if (restore_sigregs32(regs, &frame->sregs))
                 goto badframe;
+        if (restore_sigregs_gprs_high(regs, frame->gprs_high))
+                goto badframe;
 
         return regs->gprs[2];
 
@@ -394,6 +422,8 @@ asmlinkage long sys32_rt_sigreturn(void)
 
         if (restore_sigregs32(regs, &frame->uc.uc_mcontext))
                 goto badframe;
+        if (restore_sigregs_gprs_high(regs, frame->gprs_high))
+                goto badframe;
 
         err = __get_user(ss_sp, &frame->uc.uc_stack.ss_sp);
         st.ss_sp = compat_ptr(ss_sp);
@@ -474,6 +504,8 @@ static int setup_frame32(int sig, struct k_sigaction *ka,
 
         if (save_sigregs32(regs, &frame->sregs))
                 goto give_sigsegv;
+        if (save_sigregs_gprs_high(regs, frame->gprs_high))
+                goto give_sigsegv;
         if (__put_user((unsigned long) &frame->sregs, &frame->sc.sregs))
                 goto give_sigsegv;
 
@@ -529,13 +561,14 @@ static int setup_rt_frame32(int sig, struct k_sigaction *ka, siginfo_t *info,
                 goto give_sigsegv;
 
         /* Create the ucontext.  */
-        err |= __put_user(0, &frame->uc.uc_flags);
+        err |= __put_user(UC_EXTENDED, &frame->uc.uc_flags);
         err |= __put_user(0, &frame->uc.uc_link);
         err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
         err |= __put_user(sas_ss_flags(regs->gprs[15]),
                           &frame->uc.uc_stack.ss_flags);
         err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
         err |= save_sigregs32(regs, &frame->uc.uc_mcontext);
+        err |= save_sigregs_gprs_high(regs, frame->gprs_high);
         err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
         if (err)
                 goto give_sigsegv;