From 146902964d66881da797e45a5950732e38532e3e Mon Sep 17 00:00:00 2001 From: Alistair Francis Date: Wed, 18 Mar 2020 15:47:01 -0700 Subject: [PATCH] linux-user: Support futex_time64 Add support for host and target futex_time64. If futex_time64 exists on the host we try that first before falling back to the standard futex syscall. Signed-off-by: Alistair Francis Message-Id: [lv: define sys_futex() if __NR_futex is defined (fix bug on 32bit host), remove duplicate get_errno()] Signed-off-by: Laurent Vivier --- linux-user/syscall.c | 140 ++++++++++++++++++++++++++++++++++++++----- 1 file changed, 126 insertions(+), 14 deletions(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 49395dcea9..5af55fca78 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -245,7 +245,12 @@ static type name (type1 arg1,type2 arg2,type3 arg3,type4 arg4,type5 arg5, \ #define __NR_sys_rt_sigqueueinfo __NR_rt_sigqueueinfo #define __NR_sys_rt_tgsigqueueinfo __NR_rt_tgsigqueueinfo #define __NR_sys_syslog __NR_syslog -#define __NR_sys_futex __NR_futex +#if defined(__NR_futex) +# define __NR_sys_futex __NR_futex +#endif +#if defined(__NR_futex_time64) +# define __NR_sys_futex_time64 __NR_futex_time64 +#endif #define __NR_sys_inotify_init __NR_inotify_init #define __NR_sys_inotify_add_watch __NR_inotify_add_watch #define __NR_sys_inotify_rm_watch __NR_inotify_rm_watch @@ -295,10 +300,14 @@ _syscall1(int,exit_group,int,error_code) #if defined(TARGET_NR_set_tid_address) && defined(__NR_set_tid_address) _syscall1(int,set_tid_address,int *,tidptr) #endif -#if (defined(TARGET_NR_futex) || defined(TARGET_NR_exit)) && defined(__NR_futex) +#if defined(__NR_futex) _syscall6(int,sys_futex,int *,uaddr,int,op,int,val, const struct timespec *,timeout,int *,uaddr2,int,val3) #endif +#if defined(__NR_futex_time64) +_syscall6(int,sys_futex_time64,int *,uaddr,int,op,int,val, + const struct timespec *,timeout,int *,uaddr2,int,val3) +#endif #define __NR_sys_sched_getaffinity __NR_sched_getaffinity _syscall3(int, sys_sched_getaffinity, pid_t, pid, unsigned int, len, unsigned long *, user_mask_ptr); @@ -762,10 +771,14 @@ safe_syscall5(int, ppoll, struct pollfd *, ufds, unsigned int, nfds, safe_syscall6(int, epoll_pwait, int, epfd, struct epoll_event *, events, int, maxevents, int, timeout, const sigset_t *, sigmask, size_t, sigsetsize) -#ifdef TARGET_NR_futex +#if defined(__NR_futex) safe_syscall6(int,futex,int *,uaddr,int,op,int,val, \ const struct timespec *,timeout,int *,uaddr2,int,val3) #endif +#if defined(__NR_futex_time64) +safe_syscall6(int,futex_time64,int *,uaddr,int,op,int,val, \ + const struct timespec *,timeout,int *,uaddr2,int,val3) +#endif safe_syscall2(int, rt_sigsuspend, sigset_t *, newset, size_t, sigsetsize) safe_syscall2(int, kill, pid_t, pid, int, sig) safe_syscall2(int, tkill, int, tid, int, sig) @@ -1229,7 +1242,7 @@ static inline abi_long target_to_host_timespec(struct timespec *host_ts, } #endif -#if defined(TARGET_NR_clock_settime64) +#if defined(TARGET_NR_clock_settime64) || defined(TARGET_NR_futex_time64) static inline abi_long target_to_host_timespec64(struct timespec *host_ts, abi_ulong target_addr) { @@ -6916,6 +6929,55 @@ static inline abi_long host_to_target_statx(struct target_statx *host_stx, } #endif +static int do_sys_futex(int *uaddr, int op, int val, + const struct timespec *timeout, int *uaddr2, + int val3) +{ +#if HOST_LONG_BITS == 64 +#if defined(__NR_futex) + /* always a 64-bit time_t, it doesn't define _time64 version */ + return sys_futex(uaddr, op, val, timeout, uaddr2, val3); + +#endif +#else /* HOST_LONG_BITS == 64 */ +#if defined(__NR_futex_time64) + if (sizeof(timeout->tv_sec) == 8) { + /* _time64 function on 32bit arch */ + return sys_futex_time64(uaddr, op, val, timeout, uaddr2, val3); + } +#endif +#if defined(__NR_futex) + /* old function on 32bit arch */ + return sys_futex(uaddr, op, val, timeout, uaddr2, val3); +#endif +#endif /* HOST_LONG_BITS == 64 */ + g_assert_not_reached(); +} + +static int do_safe_futex(int *uaddr, int op, int val, + const struct timespec *timeout, int *uaddr2, + int val3) +{ +#if HOST_LONG_BITS == 64 +#if defined(__NR_futex) + /* always a 64-bit time_t, it doesn't define _time64 version */ + return get_errno(safe_futex(uaddr, op, val, timeout, uaddr2, val3)); +#endif +#else /* HOST_LONG_BITS == 64 */ +#if defined(__NR_futex_time64) + if (sizeof(timeout->tv_sec) == 8) { + /* _time64 function on 32bit arch */ + return get_errno(safe_futex_time64(uaddr, op, val, timeout, uaddr2, + val3)); + } +#endif +#if defined(__NR_futex) + /* old function on 32bit arch */ + return get_errno(safe_futex(uaddr, op, val, timeout, uaddr2, val3)); +#endif +#endif /* HOST_LONG_BITS == 64 */ + return -TARGET_ENOSYS; +} /* ??? Using host futex calls even when target atomic operations are not really atomic probably breaks things. However implementing @@ -6945,12 +7007,11 @@ static int do_futex(target_ulong uaddr, int op, int val, target_ulong timeout, } else { pts = NULL; } - return get_errno(safe_futex(g2h(uaddr), op, tswap32(val), - pts, NULL, val3)); + return do_safe_futex(g2h(uaddr), op, tswap32(val), pts, NULL, val3); case FUTEX_WAKE: - return get_errno(safe_futex(g2h(uaddr), op, val, NULL, NULL, 0)); + return do_safe_futex(g2h(uaddr), op, val, NULL, NULL, 0); case FUTEX_FD: - return get_errno(safe_futex(g2h(uaddr), op, val, NULL, NULL, 0)); + return do_safe_futex(g2h(uaddr), op, val, NULL, NULL, 0); case FUTEX_REQUEUE: case FUTEX_CMP_REQUEUE: case FUTEX_WAKE_OP: @@ -6960,16 +7021,63 @@ static int do_futex(target_ulong uaddr, int op, int val, target_ulong timeout, to satisfy the compiler. We do not need to tswap TIMEOUT since it's not compared to guest memory. */ pts = (struct timespec *)(uintptr_t) timeout; - return get_errno(safe_futex(g2h(uaddr), op, val, pts, - g2h(uaddr2), - (base_op == FUTEX_CMP_REQUEUE - ? tswap32(val3) - : val3))); + return do_safe_futex(g2h(uaddr), op, val, pts, g2h(uaddr2), + (base_op == FUTEX_CMP_REQUEUE + ? tswap32(val3) + : val3)); default: return -TARGET_ENOSYS; } } #endif + +#if defined(TARGET_NR_futex_time64) +static int do_futex_time64(target_ulong uaddr, int op, int val, target_ulong timeout, + target_ulong uaddr2, int val3) +{ + struct timespec ts, *pts; + int base_op; + + /* ??? We assume FUTEX_* constants are the same on both host + and target. */ +#ifdef FUTEX_CMD_MASK + base_op = op & FUTEX_CMD_MASK; +#else + base_op = op; +#endif + switch (base_op) { + case FUTEX_WAIT: + case FUTEX_WAIT_BITSET: + if (timeout) { + pts = &ts; + target_to_host_timespec64(pts, timeout); + } else { + pts = NULL; + } + return do_safe_futex(g2h(uaddr), op, tswap32(val), pts, NULL, val3); + case FUTEX_WAKE: + return do_safe_futex(g2h(uaddr), op, val, NULL, NULL, 0); + case FUTEX_FD: + return do_safe_futex(g2h(uaddr), op, val, NULL, NULL, 0); + case FUTEX_REQUEUE: + case FUTEX_CMP_REQUEUE: + case FUTEX_WAKE_OP: + /* For FUTEX_REQUEUE, FUTEX_CMP_REQUEUE, and FUTEX_WAKE_OP, the + TIMEOUT parameter is interpreted as a uint32_t by the kernel. + But the prototype takes a `struct timespec *'; insert casts + to satisfy the compiler. We do not need to tswap TIMEOUT + since it's not compared to guest memory. */ + pts = (struct timespec *)(uintptr_t) timeout; + return do_safe_futex(g2h(uaddr), op, val, pts, g2h(uaddr2), + (base_op == FUTEX_CMP_REQUEUE + ? tswap32(val3) + : val3)); + default: + return -TARGET_ENOSYS; + } +} +#endif + #if defined(TARGET_NR_name_to_handle_at) && defined(CONFIG_OPEN_BY_HANDLE) static abi_long do_name_to_handle_at(abi_long dirfd, abi_long pathname, abi_long handle, abi_long mount_id, @@ -7541,7 +7649,7 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, ts = cpu->opaque; if (ts->child_tidptr) { put_user_u32(0, ts->child_tidptr); - sys_futex(g2h(ts->child_tidptr), FUTEX_WAKE, INT_MAX, + do_sys_futex(g2h(ts->child_tidptr), FUTEX_WAKE, INT_MAX, NULL, NULL, 0); } thread_cpu = NULL; @@ -11635,6 +11743,10 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, case TARGET_NR_futex: return do_futex(arg1, arg2, arg3, arg4, arg5, arg6); #endif +#ifdef TARGET_NR_futex_time64 + case TARGET_NR_futex_time64: + return do_futex_time64(arg1, arg2, arg3, arg4, arg5, arg6); +#endif #if defined(TARGET_NR_inotify_init) && defined(__NR_inotify_init) case TARGET_NR_inotify_init: ret = get_errno(sys_inotify_init());