On Sat, Jan 27, 2007 at 11:59:55PM -0800, H. Peter Anvin wrote: > Alexey Dobriyan wrote: > >+asmlinkage long sys_lutimesat(int dfd, char __user *filename, struct > >timeval __user *utimes) > > Could we get these to take struct timespec instead of struct timeval? > > Right now we have a real problem in that the interfaces that *set* times > take struct timeval (microsecond granularity) but the interfaces that > *get* times return struct timespec (nanosecond granularity), which means > information loss on any setting operations.
OK. XFS could use it. --------------------- [PATCH 3/3] lutimesat: actual syscall and wire-up on i386 lutimesat(2) does everything futimesat(2) does except it doesn't follow symlinks. It could be used by tar(1) and cp(1). FreeBSD and NetBSD have lutimes(2) which can be emulated by C library. lutimesat(2) accepts "struct timespec" which means timestamps with nanosecond granularity. Tested on XFS which has nanosecond timestamps on-disk. Changes to do_utimes() which is used by all existing utime* syscalls pass LTP utime tests. Closes http://bugme.osdl.org/show_bug.cgi?id=4433 Signed-off-by: Alexey Dobriyan <[EMAIL PROTECTED]> --- arch/i386/kernel/syscall_table.S | 1 + fs/utimes.c | 30 +++++++++++++++++++++++++----- include/asm-i386/unistd.h | 4 ++-- 3 files changed, 28 insertions(+), 7 deletions(-) --- a/arch/i386/kernel/syscall_table.S +++ b/arch/i386/kernel/syscall_table.S @@ -319,3 +319,4 @@ ENTRY(sys_call_table) .long sys_move_pages .long sys_getcpu .long sys_epoll_pwait + .long sys_lutimesat /* 320 */ --- a/fs/utimes.c +++ b/fs/utimes.c @@ -40,7 +40,7 @@ #endif * must be owner or have write permission. * Else, update from *times, must be owner or super user. */ -long do_utimes(int dfd, char __user *filename, struct timeval *times, int flags) +static long do_utimes_nsec(int dfd, char __user *filename, struct timespec *times, int flags) { int error = -EINVAL; struct nameidata nd; @@ -69,10 +69,8 @@ long do_utimes(int dfd, char __user *fil if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) goto dput_and_out; - newattrs.ia_atime.tv_sec = times[0].tv_sec; - newattrs.ia_atime.tv_nsec = times[0].tv_usec * 1000; - newattrs.ia_mtime.tv_sec = times[1].tv_sec; - newattrs.ia_mtime.tv_nsec = times[1].tv_usec * 1000; + newattrs.ia_atime = times[0]; + newattrs.ia_mtime = times[1]; newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET; } else { error = -EACCES; @@ -92,6 +90,19 @@ out: return error; } +long do_utimes(int dfd, char __user *filename, struct timeval *times, int flags) +{ + struct timespec ts[2]; + + if (times) { + ts[0].tv_sec = times[0].tv_sec; + ts[0].tv_nsec = times[0].tv_usec * 1000; + ts[1].tv_sec = times[1].tv_sec; + ts[1].tv_nsec = times[1].tv_usec * 1000; + } + return do_utimes_nsec(dfd, filename, times ? ts : NULL, flags); +} + asmlinkage long sys_futimesat(int dfd, char __user *filename, struct timeval __user *utimes) { struct timeval times[2]; @@ -105,3 +116,12 @@ asmlinkage long sys_utimes(char __user * { return sys_futimesat(AT_FDCWD, filename, utimes); } + +asmlinkage long sys_lutimesat(int dfd, char __user *filename, struct timespec __user *utimes) +{ + struct timespec times[2]; + + if (utimes && copy_from_user(×, utimes, sizeof(times))) + return -EFAULT; + return do_utimes_nsec(dfd, filename, utimes ? times : NULL, AT_SYMLINK_NOFOLLOW); +} --- a/include/asm-i386/unistd.h +++ b/include/asm-i386/unistd.h @@ -325,10 +325,11 @@ #define __NR_vmsplice 316 #define __NR_move_pages 317 #define __NR_getcpu 318 #define __NR_epoll_pwait 319 +#define __NR_lutimesat 320 #ifdef __KERNEL__ -#define NR_syscalls 320 +#define NR_syscalls 321 #define __ARCH_WANT_IPC_PARSE_VERSION #define __ARCH_WANT_OLD_READDIR - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
