/*
- * 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/wait.h>
#include <asm/unistd.h>
-#include <asm/types.h>
-#include "user.h"
-#include "sysdep/ptrace.h"
-#include "user_util.h"
+#include "as-layout.h"
+#include "init.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 "mem.h"
#include "os.h"
#include "proc_mm.h"
-#include "skas_ptrace.h"
-#include "chan_user.h"
+#include "ptrace_user.h"
#include "registers.h"
-#include "mem.h"
-#include "uml-config.h"
-#include "process.h"
-#include "longjmp.h"
+#include "skas.h"
+#include "skas_ptrace.h"
+#include "sysdep/stub.h"
int is_skas_winch(int pid, int fd, void *data)
{
- if(pid != os_getpgrp())
- return(0);
+ return pid == getpgrp();
+}
+
+static int ptrace_dump_regs(int pid)
+{
+ unsigned long regs[MAX_REG_NR];
+ int i;
- register_winch_irq(-1, fd, -1, data);
- return(1);
+ if (ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
+ return -errno;
+
+ 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;
}
-void wait_stub_done(int pid, int sig, char * fname)
+/*
+ * Signals that are OK to receive in the stub - we'll just continue it.
+ * SIGWINCH will happen when UML is inside a detached screen.
+ */
+#define STUB_SIG_MASK ((1 << SIGVTALRM) | (1 << SIGWINCH))
+
+/* Signals that the stub will finish with - anything else is an error */
+#define STUB_DONE_MASK (1 << SIGTRAP)
+
+void wait_stub_done(int pid)
{
int n, status, err;
- do {
- if ( sig != -1 ) {
- err = ptrace(PTRACE_CONT, pid, 0, sig);
- if(err)
- panic("%s : continue failed, errno = %d\n",
- fname, errno);
- }
- sig = 0;
-
- CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
- } while((n >= 0) && WIFSTOPPED(status) &&
- ((WSTOPSIG(status) == SIGVTALRM) ||
- /* running UML inside a detached screen can cause
- * SIGWINCHes
- */
- (WSTOPSIG(status) == SIGWINCH)));
-
- if((n < 0) || !WIFSTOPPED(status) ||
- (WSTOPSIG(status) != SIGUSR1 && WSTOPSIG(status) != SIGTRAP)){
- unsigned long regs[HOST_FRAME_SIZE];
-
- if(ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
- printk("Failed to get registers from stub, "
- "errno = %d\n", errno);
- else {
- int i;
+ while (1) {
+ CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED | __WALL));
+ if ((n < 0) || !WIFSTOPPED(status))
+ goto bad_wait;
+
+ if (((1 << WSTOPSIG(status)) & STUB_SIG_MASK) == 0)
+ break;
- printk("Stub registers -\n");
- for(i = 0; i < HOST_FRAME_SIZE; i++)
- printk("\t%d - %lx\n", i, regs[i]);
+ err = ptrace(PTRACE_CONT, pid, 0, 0);
+ if (err) {
+ printk(UM_KERN_ERR "wait_stub_done : continue failed, "
+ "errno = %d\n", errno);
+ fatal_sigsegv();
}
- panic("%s : failed to wait for SIGUSR1/SIGTRAP, "
- "pid = %d, n = %d, errno = %d, status = 0x%x\n",
- fname, pid, n, errno, status);
}
+
+ if (((1 << WSTOPSIG(status)) & STUB_DONE_MASK) != 0)
+ return;
+
+bad_wait:
+ err = ptrace_dump_regs(pid);
+ if (err)
+ printk(UM_KERN_ERR "Failed to get registers from stub, "
+ "errno = %d\n", -err);
+ printk(UM_KERN_ERR "wait_stub_done : failed to wait for SIGTRAP, "
+ "pid = %d, n = %d, errno = %d, status = 0x%x\n", pid, n, errno,
+ status);
+ fatal_sigsegv();
}
extern unsigned long current_stub_stack(void);
-void get_skas_faultinfo(int pid, struct faultinfo * fi)
+static 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)
- panic("get_skas_faultinfo - PTRACE_FAULTINFO failed, "
- "errno = %d\n", errno);
+ if (err) {
+ printk(UM_KERN_ERR "get_skas_faultinfo - "
+ "PTRACE_FAULTINFO failed, errno = %d\n", errno);
+ fatal_sigsegv();
+ }
/* Special handling for i386, which has different structs */
if (sizeof(struct ptrace_faultinfo) < sizeof(struct faultinfo))
sizeof(struct ptrace_faultinfo));
}
else {
- wait_stub_done(pid, SIGSEGV, "get_skas_faultinfo");
+ unsigned long fpregs[FP_SIZE];
+
+ err = get_fp_registers(pid, fpregs);
+ if (err < 0) {
+ printk(UM_KERN_ERR "save_fp_registers returned %d\n",
+ err);
+ fatal_sigsegv();
+ }
+ err = ptrace(PTRACE_CONT, pid, 0, SIGSEGV);
+ if (err) {
+ printk(UM_KERN_ERR "Failed to continue stub, pid = %d, "
+ "errno = %d\n", pid, errno);
+ fatal_sigsegv();
+ }
+ 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));
+
+ err = put_fp_registers(pid, fpregs);
+ if (err < 0) {
+ printk(UM_KERN_ERR "put_fp_registers returned %d\n",
+ err);
+ fatal_sigsegv();
+ }
}
}
-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, ®s->skas.faultinfo);
- segv(regs->skas.faultinfo, 0, 1, NULL);
+ get_skas_faultinfo(pid, ®s->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;
+ if ((UPT_IP(regs) >= STUB_START) && (UPT_IP(regs) < STUB_END))
+ fatal_sigsegv();
+
/* 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,
+ err = ptrace(PTRACE_POKEUSER, pid, PT_SYSCALL_NR_OFFSET,
__NR_getpid);
- if(err < 0)
- panic("handle_trap - nullifying syscall failed errno = %d\n",
- errno);
+ if (err < 0) {
+ printk(UM_KERN_ERR "handle_trap - nullifying syscall "
+ "failed, errno = %d\n", errno);
+ fatal_sigsegv();
+ }
err = ptrace(PTRACE_SYSCALL, pid, 0, 0);
- 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))
- panic("handle_trap - failed to wait at end of syscall, "
- "errno = %d, status = %d\n", errno, status);
+ if (err < 0) {
+ printk(UM_KERN_ERR "handle_trap - continuing to end of "
+ "syscall failed, errno = %d\n", errno);
+ fatal_sigsegv();
+ }
+
+ CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED | __WALL));
+ if ((err < 0) || !WIFSTOPPED(status) ||
+ (WSTOPSIG(status) != SIGTRAP + 0x80)) {
+ err = ptrace_dump_regs(pid);
+ if (err)
+ printk(UM_KERN_ERR "Failed to get registers "
+ "from process, errno = %d\n", -err);
+ printk(UM_KERN_ERR "handle_trap - failed to wait at "
+ "end of syscall, errno = %d, status = %d\n",
+ errno, status);
+ fatal_sigsegv();
+ }
}
handle_syscall(regs);
static int userspace_tramp(void *stack)
{
void *addr;
+ int err;
ptrace(PTRACE_TRACEME, 0, 0, 0);
- init_new_thread_signals();
- enable_timer();
+ signal(SIGTERM, SIG_DFL);
+ signal(SIGWINCH, SIG_IGN);
+ err = set_interval();
+ if (err) {
+ printk(UM_KERN_ERR "userspace_tramp - setting timer failed, "
+ "errno = %d\n", err);
+ exit(1);
+ }
- 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, 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, page_size(),
- PROT_READ | PROT_WRITE,
+ 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, 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_flags = SA_ONSTACK | SA_NODEFER | SA_SIGINFO;
+ sa.sa_sigaction = (void *) v;
sa.sa_restorer = NULL;
- if(sigaction(SIGSEGV, &sa, NULL) < 0)
- panic("userspace_tramp - setting SIGSEGV handler "
- "failed - errno = %d\n", errno);
+ if (sigaction(SIGSEGV, &sa, NULL) < 0) {
+ printk(UM_KERN_ERR "userspace_tramp - setting SIGSEGV "
+ "handler failed - errno = %d\n", errno);
+ exit(1);
+ }
}
- 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 */
{
void *stack;
unsigned long sp;
- int pid, status, n, flags;
+ int pid, status, n, flags, err;
- stack = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE | PROT_EXEC,
+ stack = mmap(NULL, UM_KERN_PAGE_SIZE,
+ PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- if(stack == MAP_FAILED)
- panic("start_userspace : mmap failed, errno = %d", errno);
- sp = (unsigned long) stack + PAGE_SIZE - sizeof(void *);
+ if (stack == MAP_FAILED) {
+ err = -errno;
+ printk(UM_KERN_ERR "start_userspace : mmap failed, "
+ "errno = %d\n", errno);
+ return err;
+ }
+
+ sp = (unsigned long) stack + UM_KERN_PAGE_SIZE - sizeof(void *);
+
+ flags = CLONE_FILES;
+ if (proc_mm)
+ flags |= CLONE_VM;
+ else
+ flags |= SIGCHLD;
- flags = CLONE_FILES | SIGCHLD;
- if(proc_mm) flags |= CLONE_VM;
pid = clone(userspace_tramp, (void *) sp, flags, (void *) stub_stack);
- if(pid < 0)
- panic("start_userspace : clone failed, errno = %d", errno);
+ if (pid < 0) {
+ err = -errno;
+ printk(UM_KERN_ERR "start_userspace : clone failed, "
+ "errno = %d\n", errno);
+ return err;
+ }
do {
- CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
- if(n < 0)
- panic("start_userspace : wait failed, errno = %d",
- errno);
- } while(WIFSTOPPED(status) && (WSTOPSIG(status) == SIGVTALRM));
+ CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED | __WALL));
+ if (n < 0) {
+ err = -errno;
+ printk(UM_KERN_ERR "start_userspace : wait failed, "
+ "errno = %d\n", errno);
+ goto out_kill;
+ }
+ } while (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGVTALRM));
- if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP))
- panic("start_userspace : expected SIGSTOP, got status = %d",
- status);
+ if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP)) {
+ err = -EINVAL;
+ printk(UM_KERN_ERR "start_userspace : expected SIGSTOP, got "
+ "status = %d\n", status);
+ goto out_kill;
+ }
- 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) {
+ err = -errno;
+ printk(UM_KERN_ERR "start_userspace : PTRACE_OLDSETOPTIONS "
+ "failed, errno = %d\n", errno);
+ goto out_kill;
+ }
- if(munmap(stack, PAGE_SIZE) < 0)
- panic("start_userspace : munmap failed, errno = %d\n", errno);
+ if (munmap(stack, UM_KERN_PAGE_SIZE) < 0) {
+ err = -errno;
+ printk(UM_KERN_ERR "start_userspace : munmap failed, "
+ "errno = %d\n", errno);
+ goto out_kill;
+ }
- return(pid);
+ return pid;
+
+ out_kill:
+ os_kill_ptraced_process(pid, 1);
+ return err;
}
-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];
- int local_using_sysemu; /*To prevent races if using_sysemu changes under us.*/
+ /* To prevent races if using_sysemu changes under us.*/
+ int local_using_sysemu;
+
+ /* Handle any immediate reschedules or signals */
+ interrupt_end();
+
+ if (getitimer(ITIMER_VIRTUAL, &timer))
+ printk(UM_KERN_ERR "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) {
+ /*
+ * This can legitimately fail if the process loads a
+ * bogus value into a segment register. It will
+ * segfault and PTRACE_GETREGS will read that value
+ * out of the process. However, PTRACE_SETREGS will
+ * fail. In this case, there is nothing to do but
+ * just kill the process.
+ */
+ if (ptrace(PTRACE_SETREGS, pid, 0, regs->gp))
+ fatal_sigsegv();
- while(1){
- restore_registers(pid, regs);
+ if (put_fp_registers(pid, regs->fp))
+ fatal_sigsegv();
/* Now we set local_using_sysemu to be used for one loop */
local_using_sysemu = get_using_sysemu();
- op = SELECT_PTRACE_OPERATION(local_using_sysemu, singlestepping(NULL));
+ op = SELECT_PTRACE_OPERATION(local_using_sysemu,
+ singlestepping(NULL));
- err = ptrace(op, pid, 0, 0);
- if(err)
- panic("userspace - could not resume userspace process, "
- "pid=%d, ptrace operation = %d, errno = %d\n",
- pid, op, errno);
+ if (ptrace(op, pid, 0, 0)) {
+ printk(UM_KERN_ERR "userspace - ptrace continue "
+ "failed, op = %d, errno = %d\n", op, errno);
+ fatal_sigsegv();
+ }
- CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED));
- if(err < 0)
- panic("userspace - waitpid failed, errno = %d\n",
- errno);
+ CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED | __WALL));
+ if (err < 0) {
+ printk(UM_KERN_ERR "userspace - wait failed, "
+ "errno = %d\n", errno);
+ fatal_sigsegv();
+ }
+
+ regs->is_user = 1;
+ if (ptrace(PTRACE_GETREGS, pid, 0, regs->gp)) {
+ printk(UM_KERN_ERR "userspace - PTRACE_GETREGS failed, "
+ "errno = %d\n", errno);
+ fatal_sigsegv();
+ }
+
+ if (get_fp_registers(pid, regs->fp)) {
+ printk(UM_KERN_ERR "userspace - get_fp_registers failed, "
+ "errno = %d\n", errno);
+ fatal_sigsegv();
+ }
- regs->skas.is_user = 1;
- save_registers(pid, regs);
UPT_SYSCALL_NR(regs) = -1; /* Assume: It's not a syscall */
- if(WIFSTOPPED(status)){
- switch(WSTOPSIG(status)){
+ if (WIFSTOPPED(status)) {
+ int sig = WSTOPSIG(status);
+ switch (sig) {
case SIGSEGV:
- if(PTRACE_FULL_FAULTINFO || !ptrace_faultinfo)
- user_signal(SIGSEGV, regs, pid);
+ if (PTRACE_FULL_FAULTINFO ||
+ !ptrace_faultinfo) {
+ get_skas_faultinfo(pid,
+ ®s->faultinfo);
+ (*sig_info[SIGSEGV])(SIGSEGV, regs);
+ }
else handle_segv(pid, regs);
break;
case SIGTRAP + 0x80:
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:
case SIGWINCH:
- user_signal(WSTOPSIG(status), regs, pid);
+ block_signals();
+ (*sig_info[sig])(sig, regs);
+ unblock_signals();
break;
default:
- printk("userspace - child stopped with signal "
- "%d\n", WSTOPSIG(status));
+ printk(UM_KERN_ERR "userspace - child stopped "
+ "with signal %d\n", sig);
+ fatal_sigsegv();
}
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[FP_SIZE];
+
+static int __init init_thread_regs(void)
+{
+ get_safe_registers(thread_regs, thread_fp_regs);
+ /* Set parent's instruction pointer to start of clone-stub */
+ thread_regs[REGS_IP_INDEX] = STUB_CODE +
+ (unsigned long) stub_clone_handler -
+ (unsigned long) &__syscall_stub_start;
+ thread_regs[REGS_SP_INDEX] = STUB_DATA + UM_KERN_PAGE_SIZE -
+ sizeof(void *);
+#ifdef __SIGNAL_FRAMESIZE
+ thread_regs[REGS_SP_INDEX] -= __SIGNAL_FRAMESIZE;
+#endif
+ return 0;
+}
+
+__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 regs[HOST_FRAME_SIZE];
- unsigned long fp_regs[HOST_FP_SIZE];
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() }})});
- get_safe_registers(regs, fp_regs);
-
- /* Set parent's instruction pointer to start of clone-stub */
- regs[REGS_IP_INDEX] = UML_CONFIG_STUB_CODE +
- (unsigned long) stub_clone_handler -
- (unsigned long) &__syscall_stub_start;
- regs[REGS_SP_INDEX] = UML_CONFIG_STUB_DATA + PAGE_SIZE -
- sizeof(void *);
-#ifdef __SIGNAL_FRAMESIZE
- regs[REGS_SP_INDEX] -= __SIGNAL_FRAMESIZE;
-#endif
- err = ptrace_setregs(pid, regs);
- if(err < 0)
- panic("copy_context_skas0 : PTRACE_SETREGS failed, "
- "pid = %d, errno = %d\n", pid, -err);
+ { .it_value = tv,
+ .it_interval = tv }) });
+
+ err = ptrace_setregs(pid, thread_regs);
+ if (err < 0) {
+ err = -errno;
+ printk(UM_KERN_ERR "copy_context_skas0 : PTRACE_SETREGS "
+ "failed, pid = %d, errno = %d\n", pid, -err);
+ return err;
+ }
- err = ptrace_setfpregs(pid, fp_regs);
- if(err < 0)
- panic("copy_context_skas0 : PTRACE_SETFPREGS failed, "
- "pid = %d, errno = %d\n", pid, -err);
+ err = put_fp_registers(pid, thread_fp_regs);
+ if (err < 0) {
+ printk(UM_KERN_ERR "copy_context_skas0 : put_fp_registers "
+ "failed, pid = %d, err = %d\n", pid, err);
+ return 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.
*/
- wait_stub_done(pid, 0, "copy_context_skas0");
+ err = ptrace(PTRACE_CONT, pid, 0, 0);
+ if (err) {
+ err = -errno;
+ printk(UM_KERN_ERR "Failed to continue new process, pid = %d, "
+ "errno = %d\n", pid, errno);
+ return err;
+ }
+
+ wait_stub_done(pid);
pid = data->err;
- if(pid < 0)
- panic("copy_context_skas0 - stub-parent reports error %d\n",
- -pid);
+ if (pid < 0) {
+ printk(UM_KERN_ERR "copy_context_skas0 - stub-parent reports "
+ "error %d\n", -pid);
+ return 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, -1, "copy_context_skas0");
- if (child_data->err != UML_CONFIG_STUB_DATA)
- panic("copy_context_skas0 - stub-child reports error %ld\n",
- child_data->err);
+ wait_stub_done(pid);
+ if (child_data->err != STUB_DATA) {
+ printk(UM_KERN_ERR "copy_context_skas0 - stub-child reports "
+ "error %ld\n", child_data->err);
+ err = child_data->err;
+ goto out_kill;
+ }
if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL,
- (void *)PTRACE_O_TRACESYSGOOD) < 0)
- panic("copy_context_skas0 : PTRACE_OLDSETOPTIONS failed, "
- "errno = %d\n", errno);
+ (void *)PTRACE_O_TRACESYSGOOD) < 0) {
+ err = -errno;
+ printk(UM_KERN_ERR "copy_context_skas0 : PTRACE_OLDSETOPTIONS "
+ "failed, errno = %d\n", errno);
+ goto out_kill;
+ }
return pid;
+
+ out_kill:
+ os_kill_ptraced_process(pid, 1);
+ return err;
}
/*
* This is used only, if stub pages are needed, while proc_mm is
- * availabl. Opening /proc/mm creates a new mm_context, which lacks
+ * available. Opening /proc/mm creates a new mm_context, which lacks
* the stub-pages. Thus, we map them using /proc/mm-fd
*/
-void map_stub_pages(int fd, unsigned long code,
- unsigned long data, unsigned long stack)
+int map_stub_pages(int fd, unsigned long code, unsigned long data,
+ unsigned long stack)
{
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);
.u =
{ .mmap =
{ .addr = code,
- .len = PAGE_SIZE,
+ .len = UM_KERN_PAGE_SIZE,
.prot = PROT_EXEC,
.flags = MAP_FIXED | MAP_PRIVATE,
.fd = code_fd,
.offset = code_offset
} } });
- n = os_write_file(fd, &mmop, sizeof(mmop));
- if(n != sizeof(mmop))
- panic("map_stub_pages : /proc/mm map for code failed, "
- "err = %d\n", -n);
+ CATCH_EINTR(n = write(fd, &mmop, sizeof(mmop)));
+ if (n != sizeof(mmop)) {
+ n = errno;
+ printk(UM_KERN_ERR "mmap args - addr = 0x%lx, fd = %d, "
+ "offset = %llx\n", code, code_fd,
+ (unsigned long long) code_offset);
+ printk(UM_KERN_ERR "map_stub_pages : /proc/mm map for code "
+ "failed, err = %d\n", n);
+ return -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,
.u =
{ .mmap =
{ .addr = data,
- .len = PAGE_SIZE,
+ .len = UM_KERN_PAGE_SIZE,
.prot = PROT_READ | PROT_WRITE,
.flags = MAP_FIXED | MAP_SHARED,
.fd = map_fd,
.offset = map_offset
} } });
- n = os_write_file(fd, &mmop, sizeof(mmop));
- if(n != sizeof(mmop))
- panic("map_stub_pages : /proc/mm map for data failed, "
- "err = %d\n", -n);
+ CATCH_EINTR(n = write(fd, &mmop, sizeof(mmop)));
+ if (n != sizeof(mmop)) {
+ n = errno;
+ printk(UM_KERN_ERR "map_stub_pages : /proc/mm map for "
+ "data failed, err = %d\n", n);
+ return -n;
+ }
}
+
+ return 0;
}
-void new_thread(void *stack, void **switch_buf_ptr, void **fork_buf_ptr,
- void (*handler)(int))
+void new_thread(void *stack, jmp_buf *buf, void (*handler)(void))
{
- unsigned long flags;
- jmp_buf switch_buf, fork_buf;
-
- *switch_buf_ptr = &switch_buf;
- *fork_buf_ptr = &fork_buf;
-
- /* Somewhat subtle - siglongjmp restores the signal mask before doing
- * the longjmp. This means that when jumping from one stack to another
- * when the target stack has interrupts enabled, an interrupt may occur
- * on the source stack. This is bad when starting up a process because
- * it's not supposed to get timer ticks until it has been scheduled.
- * So, we disable interrupts around the sigsetjmp to ensure that
- * they can't happen until we get back here where they are safe.
- */
- flags = get_signals();
- block_signals();
- if(UML_SETJMP(&fork_buf) == 0)
- new_thread_proc(stack, handler);
-
- remove_sigstack();
-
- set_signals(flags);
+ (*buf)[0].JB_IP = (unsigned long) handler;
+ (*buf)[0].JB_SP = (unsigned long) stack + UM_THREAD_SIZE -
+ sizeof(void *);
}
#define INIT_JMP_NEW_THREAD 0
-#define INIT_JMP_REMOVE_SIGSTACK 1
-#define INIT_JMP_CALLBACK 2
-#define INIT_JMP_HALT 3
-#define INIT_JMP_REBOOT 4
-
-void thread_wait(void *sw, void *fb)
-{
- jmp_buf buf, **switch_buf = sw, *fork_buf;
-
- *switch_buf = &buf;
- fork_buf = fb;
- if(UML_SETJMP(&buf) == 0)
- UML_LONGJMP(fork_buf, INIT_JMP_REMOVE_SIGSTACK);
-}
+#define INIT_JMP_CALLBACK 1
+#define INIT_JMP_HALT 2
+#define INIT_JMP_REBOOT 3
-void switch_threads(void *me, void *next)
+void switch_threads(jmp_buf *me, jmp_buf *you)
{
- jmp_buf my_buf, **me_ptr = me, *next_buf = next;
-
- *me_ptr = &my_buf;
- if(UML_SETJMP(&my_buf) == 0)
- UML_LONGJMP(next_buf, 1);
+ if (UML_SETJMP(me) == 0)
+ UML_LONGJMP(you, 1);
}
static jmp_buf initial_jmpbuf;
static void *cb_arg;
static jmp_buf *cb_back;
-int start_idle_thread(void *stack, void *switch_buf_ptr, void **fork_buf_ptr)
+int start_idle_thread(void *stack, jmp_buf *switch_buf)
{
- jmp_buf **switch_buf = switch_buf_ptr;
int n;
- set_handler(SIGWINCH, (__sighandler_t) sig_handler,
- SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGALRM,
- SIGVTALRM, -1);
+ set_handler(SIGWINCH);
- *fork_buf_ptr = &initial_jmpbuf;
- n = UML_SETJMP(&initial_jmpbuf);
- switch(n){
+ /*
+ * Can't use UML_SETJMP or UML_LONGJMP here because they save
+ * and restore signals, with the possible side-effect of
+ * trying to handle any signals which came when they were
+ * blocked, which can't be done on this stack.
+ * Signals must be blocked when jumping back here and restored
+ * after returning to the jumper.
+ */
+ n = setjmp(initial_jmpbuf);
+ switch (n) {
case INIT_JMP_NEW_THREAD:
- new_thread_proc((void *) stack, new_thread_handler);
- break;
- case INIT_JMP_REMOVE_SIGSTACK:
- remove_sigstack();
+ (*switch_buf)[0].JB_IP = (unsigned long) new_thread_handler;
+ (*switch_buf)[0].JB_SP = (unsigned long) stack +
+ UM_THREAD_SIZE - sizeof(void *);
break;
case INIT_JMP_CALLBACK:
(*cb_proc)(cb_arg);
- UML_LONGJMP(cb_back, 1);
+ longjmp(*cb_back, 1);
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);
+ printk(UM_KERN_ERR "Bad sigsetjmp return in "
+ "start_idle_thread - %d\n", n);
+ fatal_sigsegv();
}
- UML_LONGJMP(*switch_buf, 1);
+ longjmp(*switch_buf, 1);
}
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();
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;
-#warning 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, "
- "errno = %d\n", errno);
+ if (err) {
+ printk(UM_KERN_ERR "__switch_mm - PTRACE_SWITCH_MM "
+ "failed, errno = %d\n", errno);
+ fatal_sigsegv();
+ }
}
else userspace_pid[0] = mm_idp->u.pid;
}
Code Review / linux-3.10.git / blobdiff