1 files changed, 168 insertions, 148 deletions

diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index ba9af8d62055..d77c81d7068a 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -1,48 +1,38 @@
 /*
- * Copyright (C) 2002- 2004 Jeff Dike (jdike@addtoit.com)
+ * Copyright (C) 2002- 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  * Licensed under the GPL
  */
 
 #include <stdlib.h>
-#include <string.h>
 #include <unistd.h>
-#include <errno.h>
-#include <signal.h>
 #include <sched.h>
-#include "ptrace_user.h"
-#include <sys/wait.h>
+#include <errno.h>
+#include <string.h>
 #include <sys/mman.h>
-#include <sys/user.h>
-#include <sys/time.h>
-#include <sys/syscall.h>
-#include <asm/types.h>
-#include "user.h"
-#include "sysdep/ptrace.h"
-#include "kern_util.h"
-#include "skas.h"
-#include "stub-data.h"
-#include "mm_id.h"
-#include "sysdep/sigcontext.h"
-#include "sysdep/stub.h"
-#include "os.h"
-#include "proc_mm.h"
-#include "skas_ptrace.h"
+#include <sys/ptrace.h>
+#include <sys/wait.h>
+#include <asm/unistd.h>
+#include "as-layout.h"
 #include "chan_user.h"
-#include "registers.h"
+#include "kern_constants.h"
 #include "mem.h"
-#include "uml-config.h"
+#include "os.h"
 #include "process.h"
-#include "longjmp.h"
-#include "kern_constants.h"
-#include "as-layout.h"
+#include "proc_mm.h"
+#include "ptrace_user.h"
+#include "registers.h"
+#include "skas.h"
+#include "skas_ptrace.h"
+#include "user.h"
+#include "sysdep/stub.h"
 
 int is_skas_winch(int pid, int fd, void *data)
 {
-        if(pid != os_getpgrp())
-                return(0);
+        if (pid != getpgrp())
+                return 0;
 
         register_winch_irq(-1, fd, -1, data, 0);
-        return(1);
+        return 1;
 }
 
 static int ptrace_dump_regs(int pid)
@@ -50,13 +40,12 @@ static int ptrace_dump_regs(int pid)
         unsigned long regs[MAX_REG_NR];
         int i;
 
-        if(ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
+        if (ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
                 return -errno;
-        else {
-                printk("Stub registers -\n");
-                for(i = 0; i < ARRAY_SIZE(regs); i++)
-                        printk("\t%d - %lx\n", i, regs[i]);
-        }
+
+        printk(UM_KERN_ERR "Stub registers -\n");
+        for (i = 0; i < ARRAY_SIZE(regs); i++)
+                printk(UM_KERN_ERR "\t%d - %lx\n", i, regs[i]);
 
         return 0;
 }
@@ -74,27 +63,28 @@ void wait_stub_done(int pid)
 {
         int n, status, err;
 
-        while(1){
+        while (1) {
                 CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
-                if((n < 0) || !WIFSTOPPED(status))
+                if ((n < 0) || !WIFSTOPPED(status))
                         goto bad_wait;
 
-                if(((1 << WSTOPSIG(status)) & STUB_SIG_MASK) == 0)
+                if (((1 << WSTOPSIG(status)) & STUB_SIG_MASK) == 0)
                         break;
 
                 err = ptrace(PTRACE_CONT, pid, 0, 0);
-                if(err)
+                if (err)
                         panic("wait_stub_done : continue failed, errno = %d\n",
                               errno);
         }
 
-        if(((1 << WSTOPSIG(status)) & STUB_DONE_MASK) != 0)
+        if (((1 << WSTOPSIG(status)) & STUB_DONE_MASK) != 0)
                 return;
 
 bad_wait:
         err = ptrace_dump_regs(pid);
-        if(err)
-                printk("Failed to get registers from stub, errno = %d\n", -err);
+        if (err)
+                printk(UM_KERN_ERR "Failed to get registers from stub, "
+                       "errno = %d\n", -err);
         panic("wait_stub_done : failed to wait for SIGUSR1/SIGTRAP, pid = %d, "
               "n = %d, errno = %d, status = 0x%x\n", pid, n, errno, status);
 }
@@ -105,9 +95,9 @@ void get_skas_faultinfo(int pid, struct faultinfo * fi)
 {
         int err;
 
-        if(ptrace_faultinfo){
+        if (ptrace_faultinfo) {
                 err = ptrace(PTRACE_FAULTINFO, pid, 0, fi);
-                if(err)
+                if (err)
                         panic("get_skas_faultinfo - PTRACE_FAULTINFO failed, "
                               "errno = %d\n", errno);
 
@@ -119,52 +109,57 @@ void get_skas_faultinfo(int pid, struct faultinfo * fi)
         }
         else {
                 err = ptrace(PTRACE_CONT, pid, 0, SIGSEGV);
-                if(err)
+                if (err)
                         panic("Failed to continue stub, pid = %d, errno = %d\n",
                               pid, errno);
                 wait_stub_done(pid);
 
-                /* faultinfo is prepared by the stub-segv-handler at start of
+                /*
+                 * faultinfo is prepared by the stub-segv-handler at start of
                  * the stub stack page. We just have to copy it.
                  */
                 memcpy(fi, (void *)current_stub_stack(), sizeof(*fi));
         }
 }
 
-static void handle_segv(int pid, union uml_pt_regs * regs)
+static void handle_segv(int pid, struct uml_pt_regs * regs)
 {
-        get_skas_faultinfo(pid, &regs->skas.faultinfo);
-        segv(regs->skas.faultinfo, 0, 1, NULL);
+        get_skas_faultinfo(pid, &regs->faultinfo);
+        segv(regs->faultinfo, 0, 1, NULL);
 }
 
-/*To use the same value of using_sysemu as the caller, ask it that value (in local_using_sysemu)*/
-static void handle_trap(int pid, union uml_pt_regs *regs, int local_using_sysemu)
+/*
+ * To use the same value of using_sysemu as the caller, ask it that value
+ * (in local_using_sysemu
+ */
+static void handle_trap(int pid, struct uml_pt_regs *regs,
+                        int local_using_sysemu)
 {
         int err, status;
 
         /* Mark this as a syscall */
-        UPT_SYSCALL_NR(regs) = PT_SYSCALL_NR(regs->skas.regs);
+        UPT_SYSCALL_NR(regs) = PT_SYSCALL_NR(regs->gp);
 
         if (!local_using_sysemu)
         {
                 err = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_NR_OFFSET,
                              __NR_getpid);
-                if(err < 0)
-                        panic("handle_trap - nullifying syscall failed errno = %d\n",
-                              errno);
+                if (err < 0)
+                        panic("handle_trap - nullifying syscall failed, "
+                              "errno = %d\n", errno);
 
                 err = ptrace(PTRACE_SYSCALL, pid, 0, 0);
-                if(err < 0)
-                        panic("handle_trap - continuing to end of syscall failed, "
-                              "errno = %d\n", errno);
+                if (err < 0)
+                        panic("handle_trap - continuing to end of syscall "
+                              "failed, errno = %d\n", errno);
 
                 CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED));
-                if((err < 0) || !WIFSTOPPED(status) ||
-                   (WSTOPSIG(status) != SIGTRAP + 0x80)){
+                if ((err < 0) || !WIFSTOPPED(status) ||
+                   (WSTOPSIG(status) != SIGTRAP + 0x80)) {
                         err = ptrace_dump_regs(pid);
-                        if(err)
-                                printk("Failed to get registers from process, "
-                                       "errno = %d\n", -err);
+                        if (err)
+                                printk(UM_KERN_ERR "Failed to get registers "
+                                       "from process, errno = %d\n", -err);
                         panic("handle_trap - failed to wait at end of syscall, "
                               "errno = %d, status = %d\n", errno, status);
                 }
@@ -182,63 +177,64 @@ static int userspace_tramp(void *stack)
 
         ptrace(PTRACE_TRACEME, 0, 0, 0);
 
-        init_new_thread_signals();
-        err = set_interval(1);
-        if(err)
+        signal(SIGTERM, SIG_DFL);
+        err = set_interval();
+        if (err)
                 panic("userspace_tramp - setting timer failed, errno = %d\n",
                       err);
 
-        if(!proc_mm){
-                /* This has a pte, but it can't be mapped in with the usual
+        if (!proc_mm) {
+                /*
+                 * This has a pte, but it can't be mapped in with the usual
                  * tlb_flush mechanism because this is part of that mechanism
                  */
                 int fd;
-                __u64 offset;
+                unsigned long long offset;
                 fd = phys_mapping(to_phys(&__syscall_stub_start), &offset);
-                addr = mmap64((void *) UML_CONFIG_STUB_CODE, UM_KERN_PAGE_SIZE,
+                addr = mmap64((void *) STUB_CODE, UM_KERN_PAGE_SIZE,
                               PROT_EXEC, MAP_FIXED | MAP_PRIVATE, fd, offset);
-                if(addr == MAP_FAILED){
-                        printk("mapping mmap stub failed, errno = %d\n",
-                               errno);
+                if (addr == MAP_FAILED) {
+                        printk(UM_KERN_ERR "mapping mmap stub at 0x%lx failed, "
+                               "errno = %d\n", STUB_CODE, errno);
                         exit(1);
                 }
 
-                if(stack != NULL){
+                if (stack != NULL) {
                         fd = phys_mapping(to_phys(stack), &offset);
-                        addr = mmap((void *) UML_CONFIG_STUB_DATA,
+                        addr = mmap((void *) STUB_DATA,
                                     UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,
                                     MAP_FIXED | MAP_SHARED, fd, offset);
-                        if(addr == MAP_FAILED){
-                                printk("mapping segfault stack failed, "
-                                       "errno = %d\n", errno);
+                        if (addr == MAP_FAILED) {
+                                printk(UM_KERN_ERR "mapping segfault stack "
+                                       "at 0x%lx failed, errno = %d\n",
+                                       STUB_DATA, errno);
                                 exit(1);
                         }
                 }
         }
-        if(!ptrace_faultinfo && (stack != NULL)){
+        if (!ptrace_faultinfo && (stack != NULL)) {
                 struct sigaction sa;
 
-                unsigned long v = UML_CONFIG_STUB_CODE +
+                unsigned long v = STUB_CODE +
                                   (unsigned long) stub_segv_handler -
                                   (unsigned long) &__syscall_stub_start;
 
-                set_sigstack((void *) UML_CONFIG_STUB_DATA, UM_KERN_PAGE_SIZE);
+                set_sigstack((void *) STUB_DATA, UM_KERN_PAGE_SIZE);
                 sigemptyset(&sa.sa_mask);
                 sigaddset(&sa.sa_mask, SIGIO);
                 sigaddset(&sa.sa_mask, SIGWINCH);
-                sigaddset(&sa.sa_mask, SIGALRM);
                 sigaddset(&sa.sa_mask, SIGVTALRM);
                 sigaddset(&sa.sa_mask, SIGUSR1);
                 sa.sa_flags = SA_ONSTACK;
                 sa.sa_handler = (void *) v;
                 sa.sa_restorer = NULL;
-                if(sigaction(SIGSEGV, &sa, NULL) < 0)
+                if (sigaction(SIGSEGV, &sa, NULL) < 0)
                         panic("userspace_tramp - setting SIGSEGV handler "
                               "failed - errno = %d\n", errno);
         }
 
-        os_stop_process(os_getpid());
-        return(0);
+        kill(os_getpid(), SIGSTOP);
+        return 0;
 }
 
 /* Each element set once, and only accessed by a single processor anyway */
@@ -255,44 +251,55 @@ int start_userspace(unsigned long stub_stack)
         stack = mmap(NULL, UM_KERN_PAGE_SIZE,
                      PROT_READ | PROT_WRITE | PROT_EXEC,
                      MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
-        if(stack == MAP_FAILED)
+        if (stack == MAP_FAILED)
                 panic("start_userspace : mmap failed, errno = %d", errno);
         sp = (unsigned long) stack + UM_KERN_PAGE_SIZE - sizeof(void *);
 
         flags = CLONE_FILES | SIGCHLD;
-        if(proc_mm) flags |= CLONE_VM;
+        if (proc_mm)
+                flags |= CLONE_VM;
+
         pid = clone(userspace_tramp, (void *) sp, flags, (void *) stub_stack);
-        if(pid < 0)
+        if (pid < 0)
                 panic("start_userspace : clone failed, errno = %d", errno);
 
         do {
                 CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
-                if(n < 0)
+                if (n < 0)
                         panic("start_userspace : wait failed, errno = %d",
                               errno);
-        } while(WIFSTOPPED(status) && (WSTOPSIG(status) == SIGVTALRM));
+        } while (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGVTALRM));
 
-        if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP))
+        if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP))
                 panic("start_userspace : expected SIGSTOP, got status = %d",
                       status);
 
-        if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL, (void *)PTRACE_O_TRACESYSGOOD) < 0)
-                panic("start_userspace : PTRACE_OLDSETOPTIONS failed, errno=%d\n",
-                      errno);
+        if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL,
+                   (void *) PTRACE_O_TRACESYSGOOD) < 0)
+                panic("start_userspace : PTRACE_OLDSETOPTIONS failed, "
+                      "errno = %d\n", errno);
 
-        if(munmap(stack, UM_KERN_PAGE_SIZE) < 0)
+        if (munmap(stack, UM_KERN_PAGE_SIZE) < 0)
                 panic("start_userspace : munmap failed, errno = %d\n", errno);
 
-        return(pid);
+        return pid;
 }
 
-void userspace(union uml_pt_regs *regs)
+void userspace(struct uml_pt_regs *regs)
 {
+        struct itimerval timer;
+        unsigned long long nsecs, now;
         int err, status, op, pid = userspace_pid[0];
         /* To prevent races if using_sysemu changes under us.*/
         int local_using_sysemu;
 
-        while(1){
+        if (getitimer(ITIMER_VIRTUAL, &timer))
+                printk("Failed to get itimer, errno = %d\n", errno);
+        nsecs = timer.it_value.tv_sec * UM_NSEC_PER_SEC +
+                timer.it_value.tv_usec * UM_NSEC_PER_USEC;
+        nsecs += os_nsecs();
+
+        while (1) {
                 restore_registers(pid, regs);
 
                 /* Now we set local_using_sysemu to be used for one loop */
@@ -302,26 +309,28 @@ void userspace(union uml_pt_regs *regs)
                                              singlestepping(NULL));
 
                 err = ptrace(op, pid, 0, 0);
-                if(err)
+                if (err)
                         panic("userspace - could not resume userspace process, "
                               "pid=%d, ptrace operation = %d, errno = %d\n",
                               pid, op, errno);
 
                 CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED));
-                if(err < 0)
+                if (err < 0)
                         panic("userspace - waitpid failed, errno = %d\n",
                               errno);
 
-                regs->skas.is_user = 1;
+                regs->is_user = 1;
                 save_registers(pid, regs);
                 UPT_SYSCALL_NR(regs) = -1; /* Assume: It's not a syscall */
 
-                if(WIFSTOPPED(status)){
+                if (WIFSTOPPED(status)) {
                         int sig = WSTOPSIG(status);
-                        switch(sig){
+                        switch(sig) {
                         case SIGSEGV:
-                                if(PTRACE_FULL_FAULTINFO || !ptrace_faultinfo){
-                                        get_skas_faultinfo(pid, &regs->skas.faultinfo);
+                                if (PTRACE_FULL_FAULTINFO ||
+                                    !ptrace_faultinfo) {
+                                        get_skas_faultinfo(pid,
+                                                           &regs->faultinfo);
                                         (*sig_info[SIGSEGV])(SIGSEGV, regs);
                                 }
                                 else handle_segv(pid, regs);
@@ -332,8 +341,20 @@ void userspace(union uml_pt_regs *regs)
                         case SIGTRAP:
                                 relay_signal(SIGTRAP, regs);
                                 break;
-                        case SIGIO:
                         case SIGVTALRM:
+                                now = os_nsecs();
+                                if(now < nsecs)
+                                        break;
+                                block_signals();
+                                (*sig_info[sig])(sig, regs);
+                                unblock_signals();
+                                nsecs = timer.it_value.tv_sec *
+                                        UM_NSEC_PER_SEC +
+                                        timer.it_value.tv_usec *
+                                        UM_NSEC_PER_USEC;
+                                nsecs += os_nsecs();
+                                break;
+                        case SIGIO:
                         case SIGILL:
                         case SIGBUS:
                         case SIGFPE:
@@ -343,30 +364,29 @@ void userspace(union uml_pt_regs *regs)
                                 unblock_signals();
                                 break;
                         default:
-                                printk("userspace - child stopped with signal "
-                                       "%d\n", sig);
+                                printk(UM_KERN_ERR "userspace - child stopped "
+                                       "with signal %d\n", sig);
                         }
                         pid = userspace_pid[0];
                         interrupt_end();
 
                         /* Avoid -ERESTARTSYS handling in host */
-                        if(PT_SYSCALL_NR_OFFSET != PT_SYSCALL_RET_OFFSET)
-                                PT_SYSCALL_NR(regs->skas.regs) = -1;
+                        if (PT_SYSCALL_NR_OFFSET != PT_SYSCALL_RET_OFFSET)
+                                PT_SYSCALL_NR(regs->gp) = -1;
                 }
         }
 }
 
 static unsigned long thread_regs[MAX_REG_NR];
-static unsigned long thread_fp_regs[HOST_FP_SIZE];
 
 static int __init init_thread_regs(void)
 {
-        get_safe_registers(thread_regs, thread_fp_regs);
+        get_safe_registers(thread_regs);
         /* Set parent's instruction pointer to start of clone-stub */
-        thread_regs[REGS_IP_INDEX] = UML_CONFIG_STUB_CODE +
+        thread_regs[REGS_IP_INDEX] = STUB_CODE +
                                 (unsigned long) stub_clone_handler -
                                 (unsigned long) &__syscall_stub_start;
-        thread_regs[REGS_SP_INDEX] = UML_CONFIG_STUB_DATA + UM_KERN_PAGE_SIZE -
+        thread_regs[REGS_SP_INDEX] = STUB_DATA + UM_KERN_PAGE_SIZE -
                 sizeof(void *);
 #ifdef __SIGNAL_FRAMESIZE
         thread_regs[REGS_SP_INDEX] -= __SIGNAL_FRAMESIZE;
@@ -378,53 +398,53 @@ __initcall(init_thread_regs);
 
 int copy_context_skas0(unsigned long new_stack, int pid)
 {
+        struct timeval tv = { .tv_sec = 0, .tv_usec = UM_USEC_PER_SEC / UM_HZ };
         int err;
         unsigned long current_stack = current_stub_stack();
         struct stub_data *data = (struct stub_data *) current_stack;
         struct stub_data *child_data = (struct stub_data *) new_stack;
-        __u64 new_offset;
+        unsigned long long new_offset;
         int new_fd = phys_mapping(to_phys((void *)new_stack), &new_offset);
 
-        /* prepare offset and fd of child's stack as argument for parent's
+        /*
+         * prepare offset and fd of child's stack as argument for parent's
          * and child's mmap2 calls
          */
         *data = ((struct stub_data) { .offset   = MMAP_OFFSET(new_offset),
                                       .fd       = new_fd,
                                       .timer    = ((struct itimerval)
-                                                    { { 0, 1000000 / hz() },
-                                                      { 0, 1000000 / hz() }})});
+                                                   { .it_value = tv,
+                                                     .it_interval = tv }) });
+
         err = ptrace_setregs(pid, thread_regs);
-        if(err < 0)
+        if (err < 0)
                 panic("copy_context_skas0 : PTRACE_SETREGS failed, "
                       "pid = %d, errno = %d\n", pid, -err);
 
-        err = ptrace_setfpregs(pid, thread_fp_regs);
-        if(err < 0)
-                panic("copy_context_skas0 : PTRACE_SETFPREGS failed, "
-                      "pid = %d, errno = %d\n", pid, -err);
-
         /* set a well known return code for detection of child write failure */
         child_data->err = 12345678;
 
-        /* Wait, until parent has finished its work: read child's pid from
+        /*
+         * Wait, until parent has finished its work: read child's pid from
          * parent's stack, and check, if bad result.
          */
         err = ptrace(PTRACE_CONT, pid, 0, 0);
-        if(err)
+        if (err)
                 panic("Failed to continue new process, pid = %d, "
                       "errno = %d\n", pid, errno);
         wait_stub_done(pid);
 
         pid = data->err;
-        if(pid < 0)
+        if (pid < 0)
                 panic("copy_context_skas0 - stub-parent reports error %d\n",
                       -pid);
 
-        /* Wait, until child has finished too: read child's result from
+        /*
+         * Wait, until child has finished too: read child's result from
          * child's stack and check it.
          */
         wait_stub_done(pid);
-        if (child_data->err != UML_CONFIG_STUB_DATA)
+        if (child_data->err != STUB_DATA)
                 panic("copy_context_skas0 - stub-child reports error %ld\n",
                       child_data->err);
 
@@ -446,7 +466,7 @@ void map_stub_pages(int fd, unsigned long code,
 {
         struct proc_mm_op mmop;
         int n;
-        __u64 code_offset;
+        unsigned long long code_offset;
         int code_fd = phys_mapping(to_phys((void *) &__syscall_stub_start),
                                    &code_offset);
 
@@ -461,16 +481,17 @@ void map_stub_pages(int fd, unsigned long code,
                                           .offset  = code_offset
         } } });
         CATCH_EINTR(n = write(fd, &mmop, sizeof(mmop)));
-        if(n != sizeof(mmop)){
+        if (n != sizeof(mmop)) {
                 n = errno;
-                printk("mmap args - addr = 0x%lx, fd = %d, offset = %llx\n",
-                       code, code_fd, (unsigned long long) code_offset);
+                printk(UM_KERN_ERR "mmap args - addr = 0x%lx, fd = %d, "
+                       "offset = %llx\n", code, code_fd,
+                       (unsigned long long) code_offset);
                 panic("map_stub_pages : /proc/mm map for code failed, "
                       "err = %d\n", n);
         }
 
-        if ( stack ) {
-                __u64 map_offset;
+        if (stack) {
+                unsigned long long map_offset;
                 int map_fd = phys_mapping(to_phys((void *)stack), &map_offset);
                 mmop = ((struct proc_mm_op)
                                 { .op        = MM_MMAP,
@@ -484,7 +505,7 @@ void map_stub_pages(int fd, unsigned long code,
                                       .offset  = map_offset
                 } } });
                 CATCH_EINTR(n = write(fd, &mmop, sizeof(mmop)));
-                if(n != sizeof(mmop))
+                if (n != sizeof(mmop))
                         panic("map_stub_pages : /proc/mm map for data failed, "
                               "err = %d\n", errno);
         }
@@ -504,7 +525,7 @@ void new_thread(void *stack, jmp_buf *buf, void (*handler)(void))
 
 void switch_threads(jmp_buf *me, jmp_buf *you)
 {
-        if(UML_SETJMP(me) == 0)
+        if (UML_SETJMP(me) == 0)
                 UML_LONGJMP(you, 1);
 }
 
@@ -520,8 +541,7 @@ int start_idle_thread(void *stack, jmp_buf *switch_buf)
         int n;
 
         set_handler(SIGWINCH, (__sighandler_t) sig_handler,
-                    SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGALRM,
-                    SIGVTALRM, -1);
+                    SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGVTALRM, -1);
 
         /*
          * Can't use UML_SETJMP or UML_LONGJMP here because they save
@@ -532,7 +552,7 @@ int start_idle_thread(void *stack, jmp_buf *switch_buf)
          * after returning to the jumper.
          */
         n = setjmp(initial_jmpbuf);
-        switch(n){
+        switch(n) {
         case INIT_JMP_NEW_THREAD:
                 (*switch_buf)[0].JB_IP = (unsigned long) new_thread_handler;
                 (*switch_buf)[0].JB_SP = (unsigned long) stack +
@@ -544,10 +564,10 @@ int start_idle_thread(void *stack, jmp_buf *switch_buf)
                 break;
         case INIT_JMP_HALT:
                 kmalloc_ok = 0;
-                return(0);
+                return 0;
         case INIT_JMP_REBOOT:
                 kmalloc_ok = 0;
-                return(1);
+                return 1;
         default:
                 panic("Bad sigsetjmp return in start_idle_thread - %d\n", n);
         }
@@ -563,7 +583,7 @@ void initial_thread_cb_skas(void (*proc)(void *), void *arg)
         cb_back = &here;
 
         block_signals();
-        if(UML_SETJMP(&here) == 0)
+        if (UML_SETJMP(&here) == 0)
                 UML_LONGJMP(&initial_jmpbuf, INIT_JMP_CALLBACK);
         unblock_signals();
 
@@ -584,16 +604,16 @@ void reboot_skas(void)
         UML_LONGJMP(&initial_jmpbuf, INIT_JMP_REBOOT);
 }
 
-void switch_mm_skas(struct mm_id *mm_idp)
+void __switch_mm(struct mm_id *mm_idp)
 {
         int err;
 
-        /* FIXME: need cpu pid in switch_mm_skas */
-        if(proc_mm){
+        /* FIXME: need cpu pid in __switch_mm */
+        if (proc_mm) {
                 err = ptrace(PTRACE_SWITCH_MM, userspace_pid[0], 0,
                              mm_idp->u.mm_fd);
-                if(err)
-                        panic("switch_mm_skas - PTRACE_SWITCH_MM failed, "
+                if (err)
+                        panic("__switch_mm - PTRACE_SWITCH_MM failed, "
                               "errno = %d\n", errno);
         }
         else userspace_pid[0] = mm_idp->u.pid;