On Thu, Mar 18, 2021 at 08:02:30AM -0700, Darrick J. Wong wrote:
> On Thu, Mar 18, 2021 at 07:23:10AM +0100, Christoph Hellwig wrote:
> > > +/* open_tree() */
> > > +#ifndef OPEN_TREE_CLONE
> > > +#define OPEN_TREE_CLONE 1
> > > +#endif
> > > +
> > > +#ifndef OPEN_TREE_CLOEXEC
> > > +#define OPEN_TREE_CLOEXEC O_CLOEXEC
> > > +#endif
> > > +
> > > +#ifndef __NR_open_tree
> > > + #if defined __alpha__
> > > + #define __NR_open_tree 538
> > > + #elif defined _MIPS_SIM
> > > + #if _MIPS_SIM == _MIPS_SIM_ABI32 /* o32 */
> > > + #define __NR_open_tree 4428
> > > + #endif
> > > + #if _MIPS_SIM == _MIPS_SIM_NABI32 /* n32 */
> > > + #define __NR_open_tree 6428
> > > + #endif
> > > + #if _MIPS_SIM == _MIPS_SIM_ABI64 /* n64 */
> > > + #define __NR_open_tree 5428
> > > + #endif
> > > + #elif defined __ia64__
> > > + #define __NR_open_tree (428 + 1024)
> > > + #else
> > > + #define __NR_open_tree 428
> > > + #endif
> > > +#endif
> > > +
> > > +/* move_mount() */
> > > +#ifndef MOVE_MOUNT_F_EMPTY_PATH
> > > +#define MOVE_MOUNT_F_EMPTY_PATH 0x00000004 /* Empty from path permitted */
> > > +#endif
> > > +
> > > +#ifndef __NR_move_mount
> > > + #if defined __alpha__
> > > + #define __NR_move_mount 539
> > > + #elif defined _MIPS_SIM
> > > + #if _MIPS_SIM == _MIPS_SIM_ABI32 /* o32 */
> > > + #define __NR_move_mount 4429
> > > + #endif
> > > + #if _MIPS_SIM == _MIPS_SIM_NABI32 /* n32 */
> > > + #define __NR_move_mount 6429
> > > + #endif
> > > + #if _MIPS_SIM == _MIPS_SIM_ABI64 /* n64 */
> > > + #define __NR_move_mount 5429
> > > + #endif
> > > + #elif defined __ia64__
> > > + #define __NR_move_mount (428 + 1024)
> > > + #else
> > > + #define __NR_move_mount 429
> > > + #endif
> > > +#endif
> > > +
> > > +static inline int sys_open_tree(int dfd, const char *filename, unsigned int flags)
> > > +{
> > > + return syscall(__NR_open_tree, dfd, filename, flags);
> > > +}
> > > +
> > > +static inline int sys_move_mount(int from_dfd, const char *from_pathname, int to_dfd,
> > > + const char *to_pathname, unsigned int flags)
> > > +{
> > > + return syscall(__NR_move_mount, from_dfd, from_pathname, to_dfd, to_pathname, flags);
> > > +}
> >
> > Not directly new in your patch, but I wish we'd have a central header
> > for missing UAPI bits in xfstests instead of spreading it over
> > various files.
>
> FWIW if you (or anyone else) /does/ create a src/linux_calls.h or
> similar for things like this, I will totally start adding things to it
> instead of scattering them everywhere. :)
I do usually have in my C projects two .h files (without corresponding
.c files):
1. syscall_numbers.h
https://github.com/lxc/lxc/blob/master/src/lxc/syscall_numbers.h
Where syscall_numbers defines the missing syscall numbers. For new
syscalls in the style exhibited in this patch and for legacy syscalls
it's a bit more nasty (i.e. syscalls before we unified numbering [apart
from alpha]):
#ifndef __NR_memfd_create
#if defined __i386__
#define __NR_memfd_create 356
#elif defined __x86_64__
#define __NR_memfd_create 319
#elif defined __arm__
#define __NR_memfd_create 385
#elif defined __aarch64__
#define __NR_memfd_create 279
#elif defined __s390__
#define __NR_memfd_create 350
#elif defined __powerpc__
#define __NR_memfd_create 360
#elif defined __riscv
#define __NR_memfd_create 279
#elif defined __sparc__
#define __NR_memfd_create 348
#elif defined __blackfin__
#define __NR_memfd_create 390
#elif defined __ia64__
#define __NR_memfd_create 1340
#elif defined _MIPS_SIM
#if _MIPS_SIM == _MIPS_SIM_ABI32
#define __NR_memfd_create 4354
#endif
#if _MIPS_SIM == _MIPS_SIM_NABI32
#define __NR_memfd_create 6318
#endif
#if _MIPS_SIM == _MIPS_SIM_ABI64
#define __NR_memfd_create 5314
#endif
#else
#define -1
#warning "__NR_memfd_create not defined for your architecture"
#endif
#endif
2. syscall_wrappers.h
https://github.com/lxc/lxc/blob/master/src/lxc/syscall_wrappers.h
Where syscall_wrappers.h defines minimal wrappers for missing
syscalls and their corresponding types.
#ifndef HAVE_SYS_SIGNALFD_H
struct signalfd_siginfo {
uint32_t ssi_signo;
int32_t ssi_errno;
int32_t ssi_code;
uint32_t ssi_pid;
uint32_t ssi_uid;
int32_t ssi_fd;
uint32_t ssi_tid;
uint32_t ssi_band;
uint32_t ssi_overrun;
uint32_t ssi_trapno;
int32_t ssi_status;
int32_t ssi_int;
uint64_t ssi_ptr;
uint64_t ssi_utime;
uint64_t ssi_stime;
uint64_t ssi_addr;
uint8_t __pad[48];
};
static inline int signalfd(int fd, const sigset_t *mask, int flags)
{
int retval;
retval = syscall(__NR_signalfd4, fd, mask, _NSIG / 8, flags);
#ifdef __NR_signalfd
if (errno == ENOSYS && flags == 0)
retval = syscall(__NR_signalfd, fd, mask, _NSIG / 8);
#endif
return retval;
}
#endif
Something like this might also work for xfstests.
Christian
