From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932138AbVLPLoN (ORCPT ); Fri, 16 Dec 2005 06:44:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932201AbVLPLoN (ORCPT ); Fri, 16 Dec 2005 06:44:13 -0500 Received: from canuck.infradead.org ([205.233.218.70]:32700 "EHLO canuck.infradead.org") by vger.kernel.org with ESMTP id S932138AbVLPLoM (ORCPT ); Fri, 16 Dec 2005 06:44:12 -0500 Subject: [PATCH] [1/6] Add pselect/ppoll system call implementation From: David Woodhouse To: akpm@osdl.org Cc: dhowells , linux-kernel@vger.kernel.org In-Reply-To: <1134732739.7104.54.camel@pmac.infradead.org> References: <1134732739.7104.54.camel@pmac.infradead.org> Content-Type: text/plain Date: Fri, 16 Dec 2005 11:43:57 +0000 Message-Id: <1134733438.7104.89.camel@pmac.infradead.org> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Content-Transfer-Encoding: 7bit X-Bad-Reply: References and In-Reply-To but no 'Re:' in Subject. X-Spam-Score: 0.0 (/) X-SRS-Rewrite: SMTP reverse-path rewritten from by canuck.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org This patch adds the pselect() and ppoll() system calls. Most of this implementation is as it was in the -mm kernel for a period of time already before the difficulties with signal delivery became apparent. Signed-Off-By: David Woodhouse fs/compat.c | 252 +++++++++++++++++++++++++++++++------ fs/select.c | 337 +++++++++++++++++++++++++++++++++++++++++--------- include/linux/poll.h | 6 include/linux/sched.h | 1 4 files changed, 501 insertions(+), 95 deletions(-) diff -uNrp linux-2.6.15-rc5-mm3/fs/compat.c linux-2.6.15-rc5-mm3-pselect1/fs/compat.c --- linux-2.6.15-rc5-mm3/fs/compat.c 2005-12-16 10:56:15.000000000 +0000 +++ linux-2.6.15-rc5-mm3-pselect1/fs/compat.c 2005-12-16 11:01:04.000000000 +0000 @@ -53,6 +53,8 @@ #include #include +extern void sigset_from_compat(sigset_t *set, compat_sigset_t *compat); + /* * Not all architectures have sys_utime, so implement this in terms * of sys_utimes. @@ -1621,36 +1623,14 @@ static void select_bits_free(void *bits, #define MAX_SELECT_SECONDS \ ((unsigned long) (MAX_SCHEDULE_TIMEOUT / HZ)-1) -asmlinkage long -compat_sys_select(int n, compat_ulong_t __user *inp, compat_ulong_t __user *outp, - compat_ulong_t __user *exp, struct compat_timeval __user *tvp) +int compat_core_sys_select(int n, compat_ulong_t __user *inp, + compat_ulong_t __user *outp, compat_ulong_t __user *exp, int64_t *timeout) { fd_set_bits fds; char *bits; - long timeout; int size, max_fdset, ret = -EINVAL; struct fdtable *fdt; - timeout = MAX_SCHEDULE_TIMEOUT; - if (tvp) { - time_t sec, usec; - - if (!access_ok(VERIFY_READ, tvp, sizeof(*tvp)) - || __get_user(sec, &tvp->tv_sec) - || __get_user(usec, &tvp->tv_usec)) { - ret = -EFAULT; - goto out_nofds; - } - - if (sec < 0 || usec < 0) - goto out_nofds; - - if ((unsigned long) sec < MAX_SELECT_SECONDS) { - timeout = ROUND_UP(usec, 1000000/HZ); - timeout += sec * (unsigned long) HZ; - } - } - if (n < 0) goto out_nofds; @@ -1687,19 +1667,7 @@ compat_sys_select(int n, compat_ulong_t zero_fd_set(n, fds.res_out); zero_fd_set(n, fds.res_ex); - ret = do_select(n, &fds, &timeout); - - if (tvp && !(current->personality & STICKY_TIMEOUTS)) { - time_t sec = 0, usec = 0; - if (timeout) { - sec = timeout / HZ; - usec = timeout % HZ; - usec *= (1000000/HZ); - } - if (put_user(sec, &tvp->tv_sec) || - put_user(usec, &tvp->tv_usec)) - ret = -EFAULT; - } + ret = do_select(n, &fds, timeout); if (ret < 0) goto out; @@ -1720,6 +1688,216 @@ out_nofds: return ret; } +asmlinkage long compat_sys_select(int n, compat_ulong_t __user *inp, + compat_ulong_t __user *outp, compat_ulong_t __user *exp, + struct compat_timeval __user *tvp) +{ + int64_t timeout = -1; + struct compat_timeval tv; + int ret; + + if (tvp) { + if (copy_from_user(&tv, tvp, sizeof(tv))) + return -EFAULT; + + if (tv.tv_sec < 0 || tv.tv_usec < 0) + return -EINVAL; + + /* Cast to uint64_t to make GCC stop complaining */ + if ((uint64_t)tv.tv_sec >= (uint64_t)MAX_INT64_SECONDS) + timeout = -1; /* infinite */ + else { + timeout = ROUND_UP(tv.tv_sec, 1000000/HZ); + timeout += tv.tv_sec * HZ; + } + } + + ret = compat_core_sys_select(n, inp, outp, exp, &timeout); + + if (tvp) { + if (current->personality & STICKY_TIMEOUTS) + goto sticky; + tv.tv_usec = jiffies_to_usecs(do_div((*(uint64_t*)&timeout), HZ)); + tv.tv_sec = timeout; + if (copy_to_user(tvp, &tv, sizeof(tv))) { + sticky: + /* + * If an application puts its timeval in read-only + * memory, we don't want the Linux-specific update to + * the timeval to cause a fault after the select has + * completed successfully. However, because we're not + * updating the timeval, we can't restart the system + * call. + */ + if (ret == -ERESTARTNOHAND) + ret = -EINTR; + } + } + + return ret; +} + +#ifdef TIF_RESTORE_SIGMASK +asmlinkage long compat_sys_pselect7(int n, compat_ulong_t __user *inp, + compat_ulong_t __user *outp, compat_ulong_t __user *exp, + struct compat_timespec __user *tsp, compat_sigset_t __user *sigmask, + compat_size_t sigsetsize) +{ + compat_sigset_t s32; + sigset_t ksigmask, sigsaved; + long timeout = MAX_SCHEDULE_TIMEOUT; + struct compat_timespec ts; + int ret; + + if (tsp) { + if (copy_from_user(&ts, tsp, sizeof(ts))) + return -EFAULT; + + if (ts.tv_sec < 0 || ts.tv_nsec < 0) + return -EINVAL; + } + + if (sigmask) { + if (sigsetsize != sizeof(compat_sigset_t)) + return -EINVAL; + if (copy_from_user(&s32, sigmask, sizeof(s32))) + return -EFAULT; + sigset_from_compat(&ksigmask, &s32); + + sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP)); + sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); + } + + do { + if (tsp) { + if ((unsigned long)ts.tv_sec < MAX_SELECT_SECONDS) { + timeout = ROUND_UP(ts.tv_nsec, 1000000000/HZ); + timeout += ts.tv_sec * (unsigned long)HZ; + ts.tv_sec = 0; + ts.tv_nsec = 0; + } else { + ts.tv_sec -= MAX_SELECT_SECONDS; + timeout = MAX_SELECT_SECONDS * HZ; + } + } + + ret = compat_core_sys_select(n, inp, outp, exp, &timeout); + + } while (!ret && !timeout && tsp && (ts.tv_sec || ts.tv_nsec)); + + if (tsp && !(current->personality & STICKY_TIMEOUTS)) { + ts.tv_sec += timeout / HZ; + ts.tv_nsec += (timeout % HZ) * (1000000000/HZ); + if (ts.tv_nsec >= 1000000000) { + ts.tv_sec++; + ts.tv_nsec -= 1000000000; + } + (void)copy_to_user(tsp, &ts, sizeof(ts)); + } + + if (ret == -ERESTARTNOHAND) { + /* Don't restore the signal mask yet. Let do_signal() deliver the signal + on the way back to userspace, before the signal mask is restored. */ + if (sigmask) { + memcpy(¤t->saved_sigmask, &sigsaved, sizeof(sigsaved)); + set_thread_flag(TIF_RESTORE_SIGMASK); + } + } else if (sigmask) + sigprocmask(SIG_SETMASK, &sigsaved, NULL); + + return ret; +} + +asmlinkage long compat_sys_pselect6(int n, compat_ulong_t __user *inp, + compat_ulong_t __user *outp, compat_ulong_t __user *exp, + struct compat_timespec __user *tsp, void __user *sig) +{ + compat_size_t sigsetsize = 0; + compat_uptr_t up = 0; + + if (sig) { + if (!access_ok(VERIFY_READ, sig, + sizeof(compat_uptr_t)+sizeof(compat_size_t)) || + __get_user(up, (compat_uptr_t __user *)sig) || + __get_user(sigsetsize, + (compat_size_t __user *)(sig+sizeof(up)))) + return -EFAULT; + } + return compat_sys_pselect7(n, inp, outp, exp, tsp, compat_ptr(up), + sigsetsize); +} + +asmlinkage long compat_sys_ppoll(struct pollfd __user *ufds, + unsigned int nfds, struct compat_timespec __user *tsp, + const compat_sigset_t __user *sigmask, compat_size_t sigsetsize) +{ + compat_sigset_t s32; + sigset_t ksigmask, sigsaved; + struct compat_timespec ts; + int64_t timeout = -1; + int ret; + + if (tsp) { + if (copy_from_user(&ts, tsp, sizeof(ts))) + return -EFAULT; + + /* We assume that ts.tv_sec is always lower than + the number of seconds that can be expressed in + an int64_t. Otherwise the compiler bitches at us */ + timeout = ROUND_UP(ts.tv_sec, 1000000000/HZ); + timeout += ts.tv_sec * HZ; + } + + if (sigmask) { + if (sigsetsize |= sizeof(compat_sigset_t)) + return -EINVAL; + if (copy_from_user(&s32, sigmask, sizeof(s32))) + return -EFAULT; + sigset_from_compat(&ksigmask, &s32); + + sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP)); + sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); + } + + ret = do_sys_poll(ufds, nfds, &timeout); + + /* We can restart this syscall, usually */ + if (ret == -EINTR) { + /* Don't restore the signal mask yet. Let do_signal() deliver the signal + on the way back to userspace, before the signal mask is restored. */ + if (sigmask) { + memcpy(¤t->saved_sigmask, &sigsaved, sizeof(sigsaved)); + set_thread_flag(TIF_RESTORE_SIGMASK); + } + ret = -ERESTARTNOHAND; + } else if (sigmask) + sigprocmask(SIG_SETMASK, &sigsaved, NULL); + + if (tsp && timeout >= 0) { + if (current->personality & STICKY_TIMEOUTS) + goto sticky; + /* Yes, we know it's actually an int64_t, but it's also positive. */ + ts.tv_nsec = jiffies_to_usecs(do_div((*(uint64_t*)&timeout), HZ)) * 1000; + ts.tv_sec = timeout; + if (copy_to_user(tsp, &ts, sizeof(ts))) { + sticky: + /* + * If an application puts its timeval in read-only + * memory, we don't want the Linux-specific update to + * the timeval to cause a fault after the select has + * completed successfully. However, because we're not + * updating the timeval, we can't restart the system + * call. + */ + if (ret == -ERESTARTNOHAND && timeout >= 0) + ret = -EINTR; + } + } + + return ret; +} +#endif /* TIF_RESTORE_SIGMASK */ + #if defined(CONFIG_NFSD) || defined(CONFIG_NFSD_MODULE) /* Stuff for NFS server syscalls... */ struct compat_nfsctl_svc { diff -uNrp linux-2.6.15-rc5-mm3/fs/select.c linux-2.6.15-rc5-mm3-pselect1/fs/select.c --- linux-2.6.15-rc5-mm3/fs/select.c 2005-10-28 01:02:08.000000000 +0100 +++ linux-2.6.15-rc5-mm3-pselect1/fs/select.c 2005-12-16 11:01:04.000000000 +0000 @@ -179,12 +179,11 @@ get_max: #define POLLOUT_SET (POLLWRBAND | POLLWRNORM | POLLOUT | POLLERR) #define POLLEX_SET (POLLPRI) -int do_select(int n, fd_set_bits *fds, long *timeout) +int do_select(int n, fd_set_bits *fds, int64_t *timeout) { struct poll_wqueues table; poll_table *wait; int retval, i; - long __timeout = *timeout; rcu_read_lock(); retval = max_select_fd(n, fds); @@ -196,11 +195,12 @@ int do_select(int n, fd_set_bits *fds, l poll_initwait(&table); wait = &table.pt; - if (!__timeout) + if (!*timeout) wait = NULL; retval = 0; for (;;) { unsigned long *rinp, *routp, *rexp, *inp, *outp, *exp; + long __timeout; set_current_state(TASK_INTERRUPTIBLE); @@ -255,22 +255,32 @@ int do_select(int n, fd_set_bits *fds, l *rexp = res_ex; } wait = NULL; - if (retval || !__timeout || signal_pending(current)) + if (retval || !*timeout || signal_pending(current)) break; if(table.error) { retval = table.error; break; } + + if (*timeout < 0) { + /* Wait indefinitely */ + __timeout = MAX_SCHEDULE_TIMEOUT; + } else if (unlikely(*timeout >= (int64_t)MAX_SCHEDULE_TIMEOUT - 1)) { + /* Wait for longer than MAX_SCHEDULE_TIMEOUT. Do it in a loop */ + __timeout = MAX_SCHEDULE_TIMEOUT - 1; + *timeout -= __timeout; + } else { + __timeout = *timeout; + *timeout = 0; + } __timeout = schedule_timeout(__timeout); + if (*timeout >= 0) + *timeout += __timeout; } __set_current_state(TASK_RUNNING); poll_freewait(&table); - /* - * Up-to-date the caller timeout. - */ - *timeout = __timeout; return retval; } @@ -295,36 +305,14 @@ static void select_bits_free(void *bits, #define MAX_SELECT_SECONDS \ ((unsigned long) (MAX_SCHEDULE_TIMEOUT / HZ)-1) -asmlinkage long -sys_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct timeval __user *tvp) +static int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp, + fd_set __user *exp, int64_t *timeout) { fd_set_bits fds; char *bits; - long timeout; int ret, size, max_fdset; struct fdtable *fdt; - timeout = MAX_SCHEDULE_TIMEOUT; - if (tvp) { - time_t sec, usec; - - if (!access_ok(VERIFY_READ, tvp, sizeof(*tvp)) - || __get_user(sec, &tvp->tv_sec) - || __get_user(usec, &tvp->tv_usec)) { - ret = -EFAULT; - goto out_nofds; - } - - ret = -EINVAL; - if (sec < 0 || usec < 0) - goto out_nofds; - - if ((unsigned long) sec < MAX_SELECT_SECONDS) { - timeout = ROUND_UP(usec, 1000000/HZ); - timeout += sec * (unsigned long) HZ; - } - } - ret = -EINVAL; if (n < 0) goto out_nofds; @@ -362,18 +350,7 @@ sys_select(int n, fd_set __user *inp, fd zero_fd_set(n, fds.res_out); zero_fd_set(n, fds.res_ex); - ret = do_select(n, &fds, &timeout); - - if (tvp && !(current->personality & STICKY_TIMEOUTS)) { - time_t sec = 0, usec = 0; - if (timeout) { - sec = timeout / HZ; - usec = timeout % HZ; - usec *= (1000000/HZ); - } - put_user(sec, &tvp->tv_sec); - put_user(usec, &tvp->tv_usec); - } + ret = do_select(n, &fds, timeout); if (ret < 0) goto out; @@ -395,6 +372,150 @@ out_nofds: return ret; } +asmlinkage long sys_select(int n, fd_set __user *inp, fd_set __user *outp, + fd_set __user *exp, struct timeval __user *tvp) +{ + int64_t timeout = -1; + struct timeval tv; + int ret; + + if (tvp) { + if (copy_from_user(&tv, tvp, sizeof(tv))) + return -EFAULT; + + if (tv.tv_sec < 0 || tv.tv_usec < 0) + return -EINVAL; + + /* Cast to uint64_t to make GCC stop complaining */ + if ((uint64_t)tv.tv_sec >= (uint64_t)MAX_INT64_SECONDS) + timeout = -1; /* infinite */ + else { + timeout = ROUND_UP(tv.tv_sec, 1000000/HZ); + timeout += tv.tv_sec * HZ; + } + } + + ret = core_sys_select(n, inp, outp, exp, &timeout); + + if (tvp) { + if (current->personality & STICKY_TIMEOUTS) + goto sticky; + tv.tv_usec = jiffies_to_usecs(do_div((*(uint64_t*)&timeout), HZ)); + tv.tv_sec = timeout; + if (copy_to_user(tvp, &tv, sizeof(tv))) { + sticky: + /* + * If an application puts its timeval in read-only + * memory, we don't want the Linux-specific update to + * the timeval to cause a fault after the select has + * completed successfully. However, because we're not + * updating the timeval, we can't restart the system + * call. + */ + if (ret == -ERESTARTNOHAND) + ret = -EINTR; + } + } + + return ret; +} + +#ifdef TIF_RESTORE_SIGMASK +asmlinkage long sys_pselect7(int n, fd_set __user *inp, fd_set __user *outp, + fd_set __user *exp, struct timespec __user *tsp, + const sigset_t __user *sigmask, size_t sigsetsize) +{ + int64_t timeout = MAX_SCHEDULE_TIMEOUT; + sigset_t ksigmask, sigsaved; + struct timespec ts; + int ret; + + if (tsp) { + if (copy_from_user(&ts, tsp, sizeof(ts))) + return -EFAULT; + + if (ts.tv_sec < 0 || ts.tv_nsec < 0) + return -EINVAL; + + /* Cast to uint64_t to make GCC stop complaining */ + if ((uint64_t)ts.tv_sec >= (uint64_t)MAX_INT64_SECONDS) + timeout = -1; /* infinite */ + else { + timeout = ROUND_UP(ts.tv_sec, 1000000000/HZ); + timeout += ts.tv_sec * HZ; + } + } + + if (sigmask) { + /* XXX: Don't preclude handling different sized sigset_t's. */ + if (sigsetsize != sizeof(sigset_t)) + return -EINVAL; + if (copy_from_user(&ksigmask, sigmask, sizeof(ksigmask))) + return -EFAULT; + + sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP)); + sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); + } + + ret = core_sys_select(n, inp, outp, exp, &timeout); + + if (tsp) { + if (current->personality & STICKY_TIMEOUTS) + goto sticky; + ts.tv_nsec = jiffies_to_usecs(do_div((*(uint64_t*)&timeout), HZ)) * 1000; + ts.tv_sec = timeout; + if (copy_to_user(tsp, &ts, sizeof(ts))) { + sticky: + /* + * If an application puts its timeval in read-only + * memory, we don't want the Linux-specific update to + * the timeval to cause a fault after the select has + * completed successfully. However, because we're not + * updating the timeval, we can't restart the system + * call. + */ + if (ret == -ERESTARTNOHAND) + ret = -EINTR; + } + } + + if (ret == -ERESTARTNOHAND) { + /* Don't restore the signal mask yet. Let do_signal() deliver the signal + on the way back to userspace, before the signal mask is restored. */ + if (sigmask) { + memcpy(¤t->saved_sigmask, &sigsaved, sizeof(sigsaved)); + set_thread_flag(TIF_RESTORE_SIGMASK); + } + } else if (sigmask) + sigprocmask(SIG_SETMASK, &sigsaved, NULL); + + return ret; +} + +/* + * Most architectures can't handle 7-argument syscalls. So we provide a + * 6-argument version where the sixth argument is a pointer to a structure + * which has a pointer to the sigset_t itself followed by a size_t containing + * the sigset size. + */ +asmlinkage long sys_pselect6(int n, fd_set __user *inp, fd_set __user *outp, + fd_set __user *exp, struct timespec __user *tsp, void __user *sig) +{ + size_t sigsetsize = 0; + sigset_t __user *up = NULL; + + if (sig) { + if (!access_ok(VERIFY_READ, sig, sizeof(void *)+sizeof(size_t)) + || __get_user(up, (sigset_t * __user *)sig) + || __get_user(sigsetsize, + (size_t * __user)(sig+sizeof(void *)))) + return -EFAULT; + } + + return sys_pselect7(n, inp, outp, exp, tsp, up, sigsetsize); +} +#endif /* TIF_RESTORE_SIGMASK */ + struct poll_list { struct poll_list *next; int len; @@ -436,16 +557,19 @@ static void do_pollfd(unsigned int num, } static int do_poll(unsigned int nfds, struct poll_list *list, - struct poll_wqueues *wait, long timeout) + struct poll_wqueues *wait, int64_t *timeout) { int count = 0; poll_table* pt = &wait->pt; - if (!timeout) + /* Optimise the no-wait case */ + if (!(*timeout)) pt = NULL; for (;;) { struct poll_list *walk; + long __timeout; + set_current_state(TASK_INTERRUPTIBLE); walk = list; while(walk != NULL) { @@ -453,18 +577,33 @@ static int do_poll(unsigned int nfds, s walk = walk->next; } pt = NULL; - if (count || !timeout || signal_pending(current)) + if (count || !*timeout || signal_pending(current)) break; count = wait->error; if (count) break; - timeout = schedule_timeout(timeout); + + if (*timeout < 0) { + /* Wait indefinitely */ + __timeout = MAX_SCHEDULE_TIMEOUT; + } else if (unlikely(*timeout >= (int64_t)MAX_SCHEDULE_TIMEOUT - 1)) { + /* Wait for longer than MAX_SCHEDULE_TIMEOUT. Do it in a loop */ + __timeout = MAX_SCHEDULE_TIMEOUT - 1; + *timeout -= __timeout; + } else { + __timeout = *timeout; + *timeout = 0; + } + + __timeout = schedule_timeout(__timeout); + if (*timeout >= 0) + *timeout += __timeout; } __set_current_state(TASK_RUNNING); return count; } -asmlinkage long sys_poll(struct pollfd __user * ufds, unsigned int nfds, long timeout) +int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds, int64_t *timeout) { struct poll_wqueues table; int fdcount, err; @@ -482,14 +621,6 @@ asmlinkage long sys_poll(struct pollfd _ if (nfds > max_fdset && nfds > OPEN_MAX) return -EINVAL; - if (timeout) { - /* Careful about overflow in the intermediate values */ - if ((unsigned long) timeout < MAX_SCHEDULE_TIMEOUT / HZ) - timeout = (unsigned long)(timeout*HZ+999)/1000+1; - else /* Negative or overflow */ - timeout = MAX_SCHEDULE_TIMEOUT; - } - poll_initwait(&table); head = NULL; @@ -519,6 +650,7 @@ asmlinkage long sys_poll(struct pollfd _ } i -= pp->len; } + fdcount = do_poll(nfds, head, &table, timeout); /* OK, now copy the revents fields back to user space. */ @@ -547,3 +679,94 @@ out_fds: poll_freewait(&table); return err; } + +asmlinkage long sys_poll(struct pollfd __user *ufds, unsigned int nfds, + long timeout_msecs) +{ + int64_t timeout_jiffies = 0; + + if (timeout_msecs) { +#if HZ > 1000 + /* We can only overflow if HZ > 1000 */ + if (timeout_msecs / 1000 > (int64_t)0x7fffffffffffffffULL / (int64_t)HZ) + timeout_jiffies = -1; + else +#endif + timeout_jiffies = msecs_to_jiffies(timeout_msecs); + } + + return do_sys_poll(ufds, nfds, &timeout_jiffies); +} + +#ifdef TIF_RESTORE_SIGMASK +asmlinkage long sys_ppoll(struct pollfd __user *ufds, unsigned int nfds, + struct timespec __user *tsp, const sigset_t __user *sigmask, + size_t sigsetsize) +{ + sigset_t ksigmask, sigsaved; + struct timespec ts; + int64_t timeout = -1; + int ret; + + if (tsp) { + if (copy_from_user(&ts, tsp, sizeof(ts))) + return -EFAULT; + + /* Cast to uint64_t to make GCC stop complaining */ + if ((uint64_t)ts.tv_sec >= (uint64_t)MAX_INT64_SECONDS) + timeout = -1; /* infinite */ + else { + timeout = ROUND_UP(ts.tv_sec, 1000000000/HZ); + timeout += ts.tv_sec * HZ; + } + } + + if (sigmask) { + /* XXX: Don't preclude handling different sized sigset_t's. */ + if (sigsetsize != sizeof(sigset_t)) + return -EINVAL; + if (copy_from_user(&ksigmask, sigmask, sizeof(ksigmask))) + return -EFAULT; + + sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP)); + sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); + } + + ret = do_sys_poll(ufds, nfds, &timeout); + + /* We can restart this syscall, usually */ + if (ret == -EINTR) { + /* Don't restore the signal mask yet. Let do_signal() deliver the signal + on the way back to userspace, before the signal mask is restored. */ + if (sigmask) { + memcpy(¤t->saved_sigmask, &sigsaved, sizeof(sigsaved)); + set_thread_flag(TIF_RESTORE_SIGMASK); + } + ret = -ERESTARTNOHAND; + } else if (sigmask) + sigprocmask(SIG_SETMASK, &sigsaved, NULL); + + if (tsp && timeout >= 0) { + if (current->personality & STICKY_TIMEOUTS) + goto sticky; + /* Yes, we know it's actually an int64_t, but it's also positive. */ + ts.tv_nsec = jiffies_to_usecs(do_div((*(uint64_t*)&timeout), HZ)) * 1000; + ts.tv_sec = timeout; + if (copy_to_user(tsp, &ts, sizeof(ts))) { + sticky: + /* + * If an application puts its timeval in read-only + * memory, we don't want the Linux-specific update to + * the timeval to cause a fault after the select has + * completed successfully. However, because we're not + * updating the timeval, we can't restart the system + * call. + */ + if (ret == -ERESTARTNOHAND && timeout >= 0) + ret = -EINTR; + } + } + + return ret; +} +#endif /* TIF_RESTORE_SIGMASK */ diff -uNrp linux-2.6.15-rc5-mm3/include/linux/poll.h linux-2.6.15-rc5-mm3-pselect1/include/linux/poll.h --- linux-2.6.15-rc5-mm3/include/linux/poll.h 2005-10-28 01:02:08.000000000 +0100 +++ linux-2.6.15-rc5-mm3-pselect1/include/linux/poll.h 2005-12-16 11:01:04.000000000 +0000 @@ -92,7 +92,11 @@ void zero_fd_set(unsigned long nr, unsig memset(fdset, 0, FDS_BYTES(nr)); } -extern int do_select(int n, fd_set_bits *fds, long *timeout); +#define MAX_INT64_SECONDS (((int64_t)(~((uint64_t)0)>>1)/HZ)-1) + +extern int do_select(int n, fd_set_bits *fds, int64_t *timeout); +extern int do_sys_poll(struct pollfd __user * ufds, unsigned int nfds, + int64_t *timeout); #endif /* KERNEL */ diff -uNrp linux-2.6.15-rc5-mm3/include/linux/sched.h linux-2.6.15-rc5-mm3-pselect1/include/linux/sched.h --- linux-2.6.15-rc5-mm3/include/linux/sched.h 2005-12-16 10:56:18.000000000 +0000 +++ linux-2.6.15-rc5-mm3-pselect1/include/linux/sched.h 2005-12-16 11:01:04.000000000 +0000 @@ -816,6 +816,7 @@ struct task_struct { struct sighand_struct *sighand; sigset_t blocked, real_blocked; + sigset_t saved_sigmask; /* To be restored with TIF_RESTORE_SIGMASK */ struct sigpending pending; unsigned long sas_ss_sp; -- dwmw2