X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=fs%2Fselect.c;h=1815a57d225585122c22dd0a357dbdced59e1c40;hb=ae574a5d7aa1d80469dfcbaa757db2bea536ee66;hp=b80e7eb0ac0dac26325c8ac0d2b7d992c1d7da20;hpb=7078253c085c037c070ca4e8bc9e9e7f18aa1e84;p=pandora-kernel.git diff --git a/fs/select.c b/fs/select.c index b80e7eb0ac0d..1815a57d2255 100644 --- a/fs/select.c +++ b/fs/select.c @@ -22,6 +22,7 @@ #include /* for STICKY_TIMEOUTS */ #include #include +#include #include @@ -132,11 +133,13 @@ static int max_select_fd(unsigned long n, fd_set_bits *fds) unsigned long *open_fds; unsigned long set; int max; + struct fdtable *fdt; /* handle last in-complete long-word first */ set = ~(~0UL << (n & (__NFDBITS-1))); n /= __NFDBITS; - open_fds = current->files->open_fds->fds_bits+n; + fdt = files_fdtable(current->files); + open_fds = fdt->open_fds->fds_bits+n; max = 0; if (set) { set &= BITS(fds, n); @@ -176,16 +179,15 @@ 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, s64 *timeout) { struct poll_wqueues table; poll_table *wait; int retval, i; - long __timeout = *timeout; - spin_lock(¤t->files->file_lock); + rcu_read_lock(); retval = max_select_fd(n, fds); - spin_unlock(¤t->files->file_lock); + rcu_read_unlock(); if (retval < 0) return retval; @@ -193,11 +195,12 @@ int do_select(int n, fd_set_bits *fds, long *timeout) 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); @@ -252,22 +255,32 @@ int do_select(int n, fd_set_bits *fds, long *timeout) *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 >= (s64)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; } @@ -292,41 +305,23 @@ static void select_bits_free(void *bits, int size) #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, s64 *timeout) { fd_set_bits fds; char *bits; - long timeout; int ret, size, max_fdset; - - 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; - } - } + struct fdtable *fdt; ret = -EINVAL; if (n < 0) goto out_nofds; /* max_fdset can increase, so grab it once to avoid race */ - max_fdset = current->files->max_fdset; + rcu_read_lock(); + fdt = files_fdtable(current->files); + max_fdset = fdt->max_fdset; + rcu_read_unlock(); if (n > max_fdset) n = max_fdset; @@ -355,18 +350,7 @@ sys_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, s 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; @@ -388,6 +372,163 @@ 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) +{ + s64 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 u64 to make GCC stop complaining */ + if ((u64)tv.tv_sec >= (u64)MAX_INT64_SECONDS) + timeout = -1; /* infinite */ + else { + timeout = ROUND_UP(tv.tv_usec, USEC_PER_SEC/HZ); + timeout += tv.tv_sec * HZ; + } + } + + ret = core_sys_select(n, inp, outp, exp, &timeout); + + if (tvp) { + struct timeval rtv; + + if (current->personality & STICKY_TIMEOUTS) + goto sticky; + rtv.tv_usec = jiffies_to_usecs(do_div((*(u64*)&timeout), HZ)); + rtv.tv_sec = timeout; + if (timeval_compare(&rtv, &tv) >= 0) + rtv = tv; + if (copy_to_user(tvp, &rtv, sizeof(rtv))) { +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) +{ + s64 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 u64 to make GCC stop complaining */ + if ((u64)ts.tv_sec >= (u64)MAX_INT64_SECONDS) + timeout = -1; /* infinite */ + else { + timeout = ROUND_UP(ts.tv_nsec, NSEC_PER_SEC/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) { + struct timespec rts; + + if (current->personality & STICKY_TIMEOUTS) + goto sticky; + rts.tv_nsec = jiffies_to_usecs(do_div((*(u64*)&timeout), HZ)) * + 1000; + rts.tv_sec = timeout; + if (timespec_compare(&rts, &ts) >= 0) + rts = ts; + if (copy_to_user(tsp, &rts, sizeof(rts))) { +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 * __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; @@ -429,16 +570,19 @@ static void do_pollfd(unsigned int num, struct pollfd * fdpage, } static int do_poll(unsigned int nfds, struct poll_list *list, - struct poll_wqueues *wait, long timeout) + struct poll_wqueues *wait, s64 *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) { @@ -446,37 +590,53 @@ static int do_poll(unsigned int nfds, struct poll_list *list, 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 >= (s64)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, s64 *timeout) { struct poll_wqueues table; int fdcount, err; unsigned int i; struct poll_list *head; struct poll_list *walk; + struct fdtable *fdt; + int max_fdset; /* Do a sanity check on nfds ... */ - if (nfds > current->files->max_fdset && nfds > OPEN_MAX) + rcu_read_lock(); + fdt = files_fdtable(current->files); + max_fdset = fdt->max_fdset; + rcu_read_unlock(); + 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; @@ -506,6 +666,7 @@ asmlinkage long sys_poll(struct pollfd __user * ufds, unsigned int nfds, long ti } i -= pp->len; } + fdcount = do_poll(nfds, head, &table, timeout); /* OK, now copy the revents fields back to user space. */ @@ -534,3 +695,103 @@ out_fds: poll_freewait(&table); return err; } + +asmlinkage long sys_poll(struct pollfd __user *ufds, unsigned int nfds, + long timeout_msecs) +{ + s64 timeout_jiffies = 0; + + if (timeout_msecs) { +#if HZ > 1000 + /* We can only overflow if HZ > 1000 */ + if (timeout_msecs / 1000 > (s64)0x7fffffffffffffffULL / (s64)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; + s64 timeout = -1; + int ret; + + if (tsp) { + if (copy_from_user(&ts, tsp, sizeof(ts))) + return -EFAULT; + + /* Cast to u64 to make GCC stop complaining */ + if ((u64)ts.tv_sec >= (u64)MAX_INT64_SECONDS) + timeout = -1; /* infinite */ + else { + timeout = ROUND_UP(ts.tv_nsec, NSEC_PER_SEC/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) { + struct timespec rts; + + if (current->personality & STICKY_TIMEOUTS) + goto sticky; + /* Yes, we know it's actually an s64, but it's also positive. */ + rts.tv_nsec = jiffies_to_usecs(do_div((*(u64*)&timeout), HZ)) * + 1000; + rts.tv_sec = timeout; + if (timespec_compare(&rts, &ts) >= 0) + rts = ts; + if (copy_to_user(tsp, &rts, sizeof(rts))) { + 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 */