[PATCH] [1/6] Add pselect/ppoll system call implementation

From: David Woodhouse
Date: Fri Dec 16 2005 - 06:43:16 EST

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 <dwmw2@xxxxxxxxxxxxx>

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 <asm/mmu_context.h>
#include <asm/ioctls.h>

+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(&current->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(&current->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(&current->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(&current->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

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