[IA64] Add TIF_RESTORE_SIGMASK

Preparation for pselect and ppoll.
ia32 compat code not tested. :-(

Signed-off-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>

8 files changed, 43 insertions, 166 deletions

diff --git a/arch/ia64/ia32/ia32_entry.S b/arch/ia64/ia32/ia32_entry.S
index 687e5fdc9683..99b665e2b1d5 100644
--- a/arch/ia64/ia32/ia32_entry.S
+++ b/arch/ia64/ia32/ia32_entry.S
@@ -52,43 +52,6 @@ ENTRY(ia32_clone)
         br.ret.sptk.many rp
 END(ia32_clone)
 
-ENTRY(sys32_rt_sigsuspend)
-        .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
-        alloc loc1=ar.pfs,8,2,3,0               // preserve all eight input regs
-        mov loc0=rp
-        mov out0=in0                            // mask
-        mov out1=in1                            // sigsetsize
-        mov out2=sp                             // out2 = &sigscratch
-        .fframe 16
-        adds sp=-16,sp                          // allocate dummy "sigscratch"
-        ;;
-        .body
-        br.call.sptk.many rp=ia32_rt_sigsuspend
-1:      .restore sp
-        adds sp=16,sp
-        mov rp=loc0
-        mov ar.pfs=loc1
-        br.ret.sptk.many rp
-END(sys32_rt_sigsuspend)
-
-ENTRY(sys32_sigsuspend)
-        .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
-        alloc loc1=ar.pfs,8,2,3,0               // preserve all eight input regs
-        mov loc0=rp
-        mov out0=in2                            // mask (first two args are ignored)
-        ;;
-        mov out1=sp                             // out1 = &sigscratch
-        .fframe 16
-        adds sp=-16,sp                          // allocate dummy "sigscratch"
-        .body
-        br.call.sptk.many rp=ia32_sigsuspend
-1:      .restore sp
-        adds sp=16,sp
-        mov rp=loc0
-        mov ar.pfs=loc1
-        br.ret.sptk.many rp
-END(sys32_sigsuspend)
-
 GLOBAL_ENTRY(ia32_ret_from_clone)
         PT_REGS_UNWIND_INFO(0)
 {       /*
@@ -389,7 +352,7 @@ ia32_syscall_table:
         data8 sys_rt_sigpending
         data8 compat_sys_rt_sigtimedwait
         data8 sys32_rt_sigqueueinfo
-        data8 sys32_rt_sigsuspend
+        data8 compat_sys_rt_sigsuspend
         data8 sys32_pread         /* 180 */
         data8 sys32_pwrite
         data8 sys_chown /* 16-bit version */
diff --git a/arch/ia64/ia32/ia32_signal.c b/arch/ia64/ia32/ia32_signal.c
index 7b38b73e7827..b2bb7f227920 100644
--- a/arch/ia64/ia32/ia32_signal.c
+++ b/arch/ia64/ia32/ia32_signal.c
@@ -452,59 +452,20 @@ sigact_set_handler (struct k_sigaction *sa, unsigned int handler, unsigned int r
                 sa->sa.sa_handler = (__sighandler_t) (((unsigned long) restorer << 32) | handler);
 }
 
-long
-__ia32_rt_sigsuspend (compat_sigset_t *sset, unsigned int sigsetsize, struct sigscratch *scr)
+asmlinkage long
+sys32_sigsuspend (int history0, int history1, old_sigset_t mask)
 {
-        extern long ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall);
-        sigset_t oldset, set;
-
-        scr->scratch_unat = 0;  /* avoid leaking kernel bits to user level */
-        memset(&set, 0, sizeof(set));
-
-        memcpy(&set.sig, &sset->sig, sigsetsize);
-
-        sigdelsetmask(&set, ~_BLOCKABLE);
-
+        mask &= _BLOCKABLE;
         spin_lock_irq(&current->sighand->siglock);
-        {
-                oldset = current->blocked;
-                current->blocked = set;
-                recalc_sigpending();
-        }
+        current->saved_sigmask = current->blocked;
+        siginitset(&current->blocked, mask);
+        recalc_sigpending();
         spin_unlock_irq(&current->sighand->siglock);
 
-        /*
-         * The return below usually returns to the signal handler.  We need to pre-set the
-         * correct error code here to ensure that the right values get saved in sigcontext
-         * by ia64_do_signal.
-         */
-        scr->pt.r8 = -EINTR;
-        while (1) {
-                current->state = TASK_INTERRUPTIBLE;
-                schedule();
-                if (ia64_do_signal(&oldset, scr, 1))
-                        return -EINTR;
-        }
-}
-
-asmlinkage long
-ia32_rt_sigsuspend (compat_sigset_t __user *uset, unsigned int sigsetsize, struct sigscratch *scr)
-{
-        compat_sigset_t set;
-
-        if (sigsetsize > sizeof(compat_sigset_t))
-                return -EINVAL;
-
-        if (copy_from_user(&set.sig, &uset->sig, sigsetsize))
-                return -EFAULT;
-
-        return __ia32_rt_sigsuspend(&set, sigsetsize, scr);
-}
-
-asmlinkage long
-ia32_sigsuspend (unsigned int mask, struct sigscratch *scr)
-{
-        return __ia32_rt_sigsuspend((compat_sigset_t *) &mask, sizeof(mask), scr);
+        current->state = TASK_INTERRUPTIBLE;
+        schedule();
+        set_thread_flag(TIF_RESTORE_SIGMASK);
+        return -ERESTARTNOHAND;
 }
 
 asmlinkage long
diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S
index 55fd2d5471e1..156a6fa031f4 100644
--- a/arch/ia64/kernel/entry.S
+++ b/arch/ia64/kernel/entry.S
@@ -1199,32 +1199,6 @@ ENTRY(notify_resume_user)
         br.ret.sptk.many rp
 END(notify_resume_user)
 
-GLOBAL_ENTRY(sys_rt_sigsuspend)
-        .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
-        alloc loc1=ar.pfs,8,2,3,0 // preserve all eight input regs in case of syscall restart!
-        mov r9=ar.unat
-        mov loc0=rp                             // save return address
-        mov out0=in0                            // mask
-        mov out1=in1                            // sigsetsize
-        adds out2=8,sp                          // out2=&sigscratch->ar_pfs
-        ;;
-        .fframe 16
-        .spillsp ar.unat, 16
-        st8 [sp]=r9,-16                         // allocate space for ar.unat and save it
-        st8 [out2]=loc1,-8                      // save ar.pfs, out2=&sigscratch
-        .body
-        br.call.sptk.many rp=ia64_rt_sigsuspend
-.ret17: .restore sp
-        adds sp=16,sp                           // pop scratch stack space
-        ;;
-        ld8 r9=[sp]                             // load new unat from sw->caller_unat
-        mov rp=loc0
-        ;;
-        mov ar.unat=r9
-        mov ar.pfs=loc1
-        br.ret.sptk.many rp
-END(sys_rt_sigsuspend)
-
 ENTRY(sys_rt_sigreturn)
         PT_REGS_UNWIND_INFO(0)
         /*
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
index cba6ac398736..d7b7d3da1ebb 100644
--- a/arch/ia64/kernel/process.c
+++ b/arch/ia64/kernel/process.c
@@ -156,7 +156,7 @@ show_regs (struct pt_regs *regs)
 }
 
 void
-do_notify_resume_user (sigset_t *oldset, struct sigscratch *scr, long in_syscall)
+do_notify_resume_user (sigset_t *unused, struct sigscratch *scr, long in_syscall)
 {
         if (fsys_mode(current, &scr->pt)) {
                 /* defer signal-handling etc. until we return to privilege-level 0.  */
@@ -171,8 +171,8 @@ do_notify_resume_user (sigset_t *oldset, struct sigscratch *scr, long in_syscall
 #endif
 
         /* deal with pending signal delivery */
-        if (test_thread_flag(TIF_SIGPENDING))
-                ia64_do_signal(oldset, scr, in_syscall);
+        if (test_thread_flag(TIF_SIGPENDING)||test_thread_flag(TIF_RESTORE_SIGMASK))
+                ia64_do_signal(scr, in_syscall);
 }
 
 static int pal_halt        = 1;
diff --git a/arch/ia64/kernel/sigframe.h b/arch/ia64/kernel/sigframe.h
index 37b986cb86e0..9fd9a1933b3d 100644
--- a/arch/ia64/kernel/sigframe.h
+++ b/arch/ia64/kernel/sigframe.h
@@ -22,4 +22,4 @@ struct sigframe {
         struct sigcontext sc;
 };
 
-extern long ia64_do_signal (sigset_t *, struct sigscratch *, long);
+extern void ia64_do_signal (struct sigscratch *, long);
diff --git a/arch/ia64/kernel/signal.c b/arch/ia64/kernel/signal.c
index 77f8b49c7882..034b81d62bb1 100644
--- a/arch/ia64/kernel/signal.c
+++ b/arch/ia64/kernel/signal.c
@@ -41,47 +41,6 @@
 # define GET_SIGSET(k,u)        __get_user((k)->sig[0], &(u)->sig[0])
 #endif
 
-long
-ia64_rt_sigsuspend (sigset_t __user *uset, size_t sigsetsize, struct sigscratch *scr)
-{
-        sigset_t oldset, set;
-
-        /* XXX: Don't preclude handling different sized sigset_t's.  */
-        if (sigsetsize != sizeof(sigset_t))
-                return -EINVAL;
-
-        if (!access_ok(VERIFY_READ, uset, sigsetsize))
-                return -EFAULT;
-
-        if (GET_SIGSET(&set, uset))
-                return -EFAULT;
-
-        sigdelsetmask(&set, ~_BLOCKABLE);
-
-        spin_lock_irq(&current->sighand->siglock);
-        {
-                oldset = current->blocked;
-                current->blocked = set;
-                recalc_sigpending();
-        }
-        spin_unlock_irq(&current->sighand->siglock);
-
-        /*
-         * The return below usually returns to the signal handler.  We need to
-         * pre-set the correct error code here to ensure that the right values
-         * get saved in sigcontext by ia64_do_signal.
-         */
-        scr->pt.r8 = EINTR;
-        scr->pt.r10 = -1;
-
-        while (1) {
-                current->state = TASK_INTERRUPTIBLE;
-                schedule();
-                if (ia64_do_signal(&oldset, scr, 1))
-                        return -EINTR;
-        }
-}
-
 asmlinkage long
 sys_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, long arg2,
                  long arg3, long arg4, long arg5, long arg6, long arg7,
@@ -478,10 +437,11 @@ handle_signal (unsigned long sig, struct k_sigaction *ka, siginfo_t *info, sigse
  * Note that `init' is a special process: it doesn't get signals it doesn't want to
  * handle.  Thus you cannot kill init even with a SIGKILL even by mistake.
  */
-long
-ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall)
+void
+ia64_do_signal (struct sigscratch *scr, long in_syscall)
 {
         struct k_sigaction ka;
+        sigset_t *oldset;
         siginfo_t info;
         long restart = in_syscall;
         long errno = scr->pt.r8;
@@ -493,9 +453,11 @@ ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall)
          * doing anything if so.
          */
         if (!user_mode(&scr->pt))
-                return 0;
+                return;
 
-        if (!oldset)
+        if (test_thread_flag(TIF_RESTORE_SIGMASK))
+                oldset = &current->saved_sigmask;
+        else
                 oldset = &current->blocked;
 
         /*
@@ -558,8 +520,15 @@ ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall)
                  * Whee!  Actually deliver the signal.  If the delivery failed, we need to
                  * continue to iterate in this loop so we can deliver the SIGSEGV...
                  */
-                if (handle_signal(signr, &ka, &info, oldset, scr))
-                        return 1;
+                if (handle_signal(signr, &ka, &info, oldset, scr)) {
+                        /* a signal was successfully delivered; the saved
+                         * sigmask will have been stored in the signal frame,
+                         * and will be restored by sigreturn, so we can simply
+                         * clear the TIF_RESTORE_SIGMASK flag */
+                        if (test_thread_flag(TIF_RESTORE_SIGMASK))
+                                clear_thread_flag(TIF_RESTORE_SIGMASK);
+                        return;
+                }
         }
 
         /* Did we come from a system call? */
@@ -585,5 +554,11 @@ ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall)
                         }
                 }
         }
-        return 0;
+
+        /* if there's no signal to deliver, we just put the saved sigmask
+         * back */
+        if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
+                clear_thread_flag(TIF_RESTORE_SIGMASK);
+                sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
+        }
 }
diff --git a/include/asm-ia64/thread_info.h b/include/asm-ia64/thread_info.h
index 91698599f918..077d6778575a 100644
--- a/include/asm-ia64/thread_info.h
+++ b/include/asm-ia64/thread_info.h
@@ -85,6 +85,7 @@ struct thread_info {
 #define TIF_SYSCALL_TRACE       3       /* syscall trace active */
 #define TIF_SYSCALL_AUDIT       4       /* syscall auditing active */
 #define TIF_SINGLESTEP          5       /* restore singlestep on return to user mode */
+#define TIF_RESTORE_SIGMASK     6       /* restore signal mask in do_signal() */
 #define TIF_POLLING_NRFLAG      16      /* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_MEMDIE              17
 #define TIF_MCA_INIT            18      /* this task is processing MCA or INIT */
@@ -96,6 +97,7 @@ struct thread_info {
 #define _TIF_SINGLESTEP         (1 << TIF_SINGLESTEP)
 #define _TIF_SYSCALL_TRACEAUDIT (_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP)
 #define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
+#define _TIF_RESTORE_SIGMASK    (1 << TIF_RESTORE_SIGMASK)
 #define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
 #define _TIF_POLLING_NRFLAG     (1 << TIF_POLLING_NRFLAG)
@@ -104,7 +106,7 @@ struct thread_info {
 #define _TIF_FREEZE             (1 << TIF_FREEZE)
 
 /* "work to do on user-return" bits */
-#define TIF_ALLWORK_MASK        (_TIF_NOTIFY_RESUME|_TIF_SIGPENDING|_TIF_NEED_RESCHED|_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
+#define TIF_ALLWORK_MASK        (_TIF_NOTIFY_RESUME|_TIF_SIGPENDING|_TIF_NEED_RESCHED|_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_RESTORE_SIGMASK)
 /* like TIF_ALLWORK_BITS but sans TIF_SYSCALL_TRACE or TIF_SYSCALL_AUDIT */
 #define TIF_WORK_MASK           (TIF_ALLWORK_MASK&~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT))
 
diff --git a/include/asm-ia64/unistd.h b/include/asm-ia64/unistd.h
index a9e1fa4cac4d..e586739bcc15 100644
--- a/include/asm-ia64/unistd.h
+++ b/include/asm-ia64/unistd.h
@@ -300,6 +300,7 @@
 #define NR_syscalls                     281 /* length of syscall table */
 
 #define __ARCH_WANT_SYS_RT_SIGACTION
+#define __ARCH_WANT_SYS_RT_SIGSUSPEND
 
 #ifdef CONFIG_IA32_SUPPORT
 # define __ARCH_WANT_SYS_FADVISE64
@@ -310,6 +311,7 @@
 # define __ARCH_WANT_SYS_OLDUMOUNT
 # define __ARCH_WANT_SYS_SIGPENDING
 # define __ARCH_WANT_SYS_SIGPROCMASK
+# define __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
 # define __ARCH_WANT_COMPAT_SYS_TIME
 #endif