9p: darwin: Ignore O_{NOATIME, DIRECT}

Darwin doesn't have either of these flags. Darwin does have
F_NOCACHE, which is similar to O_DIRECT, but has different
enough semantics that other projects don't generally map
them automatically. In any case, we don't support O_DIRECT
on Linux at the moment either.

Signed-off-by: Keno Fischer <keno@juliacomputing.com>
[Michael Roitzsch: - Rebase for NixOS]
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>
[Will Cohen: - Adjust coding style]
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Message-Id: <20220227223522.91937-6-wwcohen@gmail.com>
[C.S.: - Fix compiler warning "unused label 'again'". ]
Link: https://lore.kernel.org/qemu-devel/11201492.CjeqJxXfGd@silver/
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
This commit is contained in:
Keno Fischer 2022-02-27 17:35:16 -05:00 committed by Christian Schoenebeck
parent 6b3b279bd6
commit 67a71e3b71
2 changed files with 16 additions and 1 deletions

View File

@ -37,10 +37,13 @@ static inline int openat_file(int dirfd, const char *name, int flags,
{
int fd, serrno, ret;
#ifndef CONFIG_DARWIN
again:
#endif
fd = openat(dirfd, name, flags | O_NOFOLLOW | O_NOCTTY | O_NONBLOCK,
mode);
if (fd == -1) {
#ifndef CONFIG_DARWIN
if (errno == EPERM && (flags & O_NOATIME)) {
/*
* The client passed O_NOATIME but we lack permissions to honor it.
@ -53,6 +56,7 @@ again:
flags &= ~O_NOATIME;
goto again;
}
#endif
return -1;
}

View File

@ -138,11 +138,20 @@ static int dotl_to_open_flags(int flags)
{ P9_DOTL_NONBLOCK, O_NONBLOCK } ,
{ P9_DOTL_DSYNC, O_DSYNC },
{ P9_DOTL_FASYNC, FASYNC },
#ifndef CONFIG_DARWIN
{ P9_DOTL_NOATIME, O_NOATIME },
/*
* On Darwin, we could map to F_NOCACHE, which is
* similar, but doesn't quite have the same
* semantics. However, we don't support O_DIRECT
* even on linux at the moment, so we just ignore
* it here.
*/
{ P9_DOTL_DIRECT, O_DIRECT },
#endif
{ P9_DOTL_LARGEFILE, O_LARGEFILE },
{ P9_DOTL_DIRECTORY, O_DIRECTORY },
{ P9_DOTL_NOFOLLOW, O_NOFOLLOW },
{ P9_DOTL_NOATIME, O_NOATIME },
{ P9_DOTL_SYNC, O_SYNC },
};
@ -171,10 +180,12 @@ static int get_dotl_openflags(V9fsState *s, int oflags)
*/
flags = dotl_to_open_flags(oflags);
flags &= ~(O_NOCTTY | O_ASYNC | O_CREAT);
#ifndef CONFIG_DARWIN
/*
* Ignore direct disk access hint until the server supports it.
*/
flags &= ~O_DIRECT;
#endif
return flags;
}