sparc: switch to generic sigaltstack

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

8 files changed, 11 insertions, 84 deletions

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 89dde2f0653a..3274f5dc8deb 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -42,6 +42,7 @@ config SPARC
         select GENERIC_STRNLEN_USER
         select MODULES_USE_ELF_RELA
         select ODD_RT_SIGACTION
+        select GENERIC_SIGALTSTACK
 
 config SPARC32
         def_bool !64BIT
diff --git a/arch/sparc/include/asm/compat_signal.h b/arch/sparc/include/asm/compat_signal.h
index b759eab9b51c..9ed1f128b4d1 100644
--- a/arch/sparc/include/asm/compat_signal.h
+++ b/arch/sparc/include/asm/compat_signal.h
@@ -18,12 +18,6 @@ struct __old_sigaction32 {
         unsigned int            sa_flags;
         unsigned                sa_restorer;     /* not used by Linux/SPARC yet */
 };
-
-typedef struct sigaltstack32 {
-        u32                     ss_sp;
-        int                     ss_flags;
-        compat_size_t           ss_size;
-} stack_t32;
 #endif
 
 #endif /* !(_COMPAT_SIGNAL_H) */
diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S
index 21fd1a8f47d2..e2a030045089 100644
--- a/arch/sparc/kernel/entry.S
+++ b/arch/sparc/kernel/entry.S
@@ -820,14 +820,6 @@ sys_sparc_pipe:
          mov    %l5, %o7
 
         .align  4
-        .globl  sys_sigaltstack
-sys_sigaltstack:
-        mov     %o7, %l5
-        mov     %fp, %o2
-        call    do_sigaltstack
-         mov    %l5, %o7
-
-        .align  4
         .globl  sys_sigstack
 sys_sigstack:
         mov     %o7, %l5
diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c
index 53e48f721ce3..9d9eb91d0de1 100644
--- a/arch/sparc/kernel/signal32.c
+++ b/arch/sparc/kernel/signal32.c
@@ -61,7 +61,7 @@ struct rt_signal_frame32 {
         compat_sigset_t         mask;
         /* __siginfo_fpu_t * */ u32 fpu_save;
         unsigned int            insns[2];
-        stack_t32               stack;
+        compat_stack_t          stack;
         unsigned int            extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
         /* Only valid if (regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
         siginfo_extra_v8plus_t  v8plus;
@@ -230,13 +230,11 @@ segv:
 asmlinkage void do_rt_sigreturn32(struct pt_regs *regs)
 {
         struct rt_signal_frame32 __user *sf;
-        unsigned int psr, pc, npc, u_ss_sp;
+        unsigned int psr, pc, npc;
         compat_uptr_t fpu_save;
         compat_uptr_t rwin_save;
-        mm_segment_t old_fs;
         sigset_t set;
         compat_sigset_t seta;
-        stack_t st;
         int err, i;
         
         /* Always make any pending restarted system calls return -EINTR */
@@ -295,20 +293,10 @@ asmlinkage void do_rt_sigreturn32(struct pt_regs *regs)
         if (!err && fpu_save)
                 err |= restore_fpu_state(regs, compat_ptr(fpu_save));
         err |= copy_from_user(&seta, &sf->mask, sizeof(compat_sigset_t));
-        err |= __get_user(u_ss_sp, &sf->stack.ss_sp);
-        st.ss_sp = compat_ptr(u_ss_sp);
-        err |= __get_user(st.ss_flags, &sf->stack.ss_flags);
-        err |= __get_user(st.ss_size, &sf->stack.ss_size);
+        err |= compat_restore_altstack(&sf->stack);
         if (err)
                 goto segv;
                 
-        /* It is more difficult to avoid calling this function than to
-           call it and ignore errors.  */
-        old_fs = get_fs();
-        set_fs(KERNEL_DS);
-        do_sigaltstack((stack_t __user *) &st, NULL, (unsigned long)sf);
-        set_fs(old_fs);
-        
         err |= __get_user(rwin_save, &sf->rwin_save);
         if (!err && rwin_save) {
                 if (restore_rwin_state(compat_ptr(rwin_save)))
@@ -642,9 +630,7 @@ static int setup_rt_frame32(struct k_sigaction *ka, struct pt_regs *regs,
         err |= copy_siginfo_to_user32(&sf->info, info);
         
         /* Setup sigaltstack */
-        err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
-        err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
-        err |= __put_user(current->sas_ss_size, &sf->stack.ss_size);
+        err |= __compat_save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
 
         switch (_NSIG_WORDS) {
         case 4: seta.sig[7] = (oldset->sig[3] >> 32);
@@ -856,29 +842,3 @@ asmlinkage int do_sys32_sigstack(u32 u_ssptr, u32 u_ossptr, unsigned long sp)
 out:
         return ret;
 }
-
-asmlinkage long do_sys32_sigaltstack(u32 ussa, u32 uossa, unsigned long sp)
-{
-        stack_t uss, uoss;
-        u32 u_ss_sp = 0;
-        int ret;
-        mm_segment_t old_fs;
-        stack_t32 __user *uss32 = compat_ptr(ussa);
-        stack_t32 __user *uoss32 = compat_ptr(uossa);
-        
-        if (ussa && (get_user(u_ss_sp, &uss32->ss_sp) ||
-                    __get_user(uss.ss_flags, &uss32->ss_flags) ||
-                    __get_user(uss.ss_size, &uss32->ss_size)))
-                return -EFAULT;
-        uss.ss_sp = compat_ptr(u_ss_sp);
-        old_fs = get_fs();
-        set_fs(KERNEL_DS);
-        ret = do_sigaltstack(ussa ? (stack_t __user *) &uss : NULL,
-                             uossa ? (stack_t __user *) &uoss : NULL, sp);
-        set_fs(old_fs);
-        if (!ret && uossa && (put_user(ptr_to_compat(uoss.ss_sp), &uoss32->ss_sp) ||
-                    __put_user(uoss.ss_flags, &uoss32->ss_flags) ||
-                    __put_user(uoss.ss_size, &uoss32->ss_size)))
-                return -EFAULT;
-        return ret;
-}
diff --git a/arch/sparc/kernel/signal_32.c b/arch/sparc/kernel/signal_32.c
index 68f9c8650af4..7391fa89651f 100644
--- a/arch/sparc/kernel/signal_32.c
+++ b/arch/sparc/kernel/signal_32.c
@@ -141,9 +141,7 @@ asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
         unsigned int psr, pc, npc;
         __siginfo_fpu_t __user *fpu_save;
         __siginfo_rwin_t __user *rwin_save;
-        mm_segment_t old_fs;
         sigset_t set;
-        stack_t st;
         int err;
 
         synchronize_user_stack();
@@ -171,8 +169,7 @@ asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
         if (!err && fpu_save)
                 err |= restore_fpu_state(regs, fpu_save);
         err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
-        
-        err |= __copy_from_user(&st, &sf->stack, sizeof(stack_t));
+        err |= restore_altstack(&sf->stack);
         
         if (err)
                 goto segv;
@@ -180,14 +177,6 @@ asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
         regs->pc = pc;
         regs->npc = npc;
         
-        /* It is more difficult to avoid calling this function than to
-         * call it and ignore errors.
-         */
-        old_fs = get_fs();
-        set_fs(KERNEL_DS);
-        do_sigaltstack((const stack_t __user *) &st, NULL, (unsigned long)sf);
-        set_fs(old_fs);
-
         err |= __get_user(rwin_save, &sf->rwin_save);
         if (!err && rwin_save) {
                 if (restore_rwin_state(rwin_save))
@@ -391,9 +380,7 @@ static int setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
         err |= __copy_to_user(&sf->mask, &oldset->sig[0], sizeof(sigset_t));
         
         /* Setup sigaltstack */
-        err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
-        err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
-        err |= __put_user(current->sas_ss_size, &sf->stack.ss_size);
+        err |= __save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
         
         if (!wsaved) {
                 err |= __copy_to_user(sf, (char *) regs->u_regs[UREG_FP],
diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c
index 689e1ba62809..176e0e7b8f60 100644
--- a/arch/sparc/kernel/signal_64.c
+++ b/arch/sparc/kernel/signal_64.c
@@ -295,7 +295,8 @@ void do_rt_sigreturn(struct pt_regs *regs)
                 err |= restore_fpu_state(regs, fpu_save);
 
         err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
-        if (err || do_sigaltstack(&sf->stack, NULL, (unsigned long)sf) == -EFAULT)
+        err |= restore_altstack(&sf->stack);
+        if (err)
                 goto segv;
 
         err |= __get_user(rwin_save, &sf->rwin_save);
@@ -403,9 +404,7 @@ setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
         }
         
         /* Setup sigaltstack */
-        err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
-        err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
-        err |= __put_user(current->sas_ss_size, &sf->stack.ss_size);
+        err |= __save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
 
         err |= copy_to_user(&sf->mask, oldset, sizeof(sigset_t));
 
diff --git a/arch/sparc/kernel/syscalls.S b/arch/sparc/kernel/syscalls.S
index e0fed7711a94..22a1098961f5 100644
--- a/arch/sparc/kernel/syscalls.S
+++ b/arch/sparc/kernel/syscalls.S
@@ -25,16 +25,10 @@ sys_nis_syscall:
 sys_memory_ordering:
         ba,pt   %xcc, sparc_memory_ordering
          add    %sp, PTREGS_OFF, %o1
-sys_sigaltstack:
-        ba,pt   %xcc, do_sigaltstack
-         add    %i6, STACK_BIAS, %o2
 #ifdef CONFIG_COMPAT
 sys32_sigstack:
         ba,pt   %xcc, do_sys32_sigstack
          mov    %i6, %o2
-sys32_sigaltstack:
-        ba,pt   %xcc, do_sys32_sigaltstack
-         mov    %i6, %o2
 #endif
         .align  32
 #ifdef CONFIG_COMPAT
diff --git a/arch/sparc/kernel/systbls_64.S b/arch/sparc/kernel/systbls_64.S
index 1009ecb92678..83ec8d467083 100644
--- a/arch/sparc/kernel/systbls_64.S
+++ b/arch/sparc/kernel/systbls_64.S
@@ -23,7 +23,7 @@ sys_call_table32:
 /*10*/  .word sys_unlink, sunos_execv, sys_chdir, sys_chown16, sys32_mknod
 /*15*/  .word sys_chmod, sys_lchown16, sys_brk, sys_nis_syscall, sys32_lseek
 /*20*/  .word sys_getpid, sys_capget, sys_capset, sys_setuid16, sys_getuid16
-/*25*/  .word sys32_vmsplice, compat_sys_ptrace, sys_alarm, sys32_sigaltstack, sys_pause
+/*25*/  .word sys32_vmsplice, compat_sys_ptrace, sys_alarm, compat_sys_sigaltstack, sys_pause
 /*30*/  .word compat_sys_utime, sys_lchown, sys_fchown, sys32_access, sys32_nice
         .word sys_chown, sys_sync, sys32_kill, compat_sys_newstat, sys32_sendfile
 /*40*/  .word compat_sys_newlstat, sys_dup, sys_sparc_pipe, compat_sys_times, sys_getuid