summaryrefslogtreecommitdiff
path: root/include/linux/syscalls.h
diff options
context:
space:
mode:
authorDominik Brodowski <linux@dominikbrodowski.net>2018-03-11 11:34:55 +0100
committerDominik Brodowski <linux@dominikbrodowski.net>2018-04-02 20:15:59 +0200
commit55731b3cda3a85ee888dac3bf1f36489f275c187 (patch)
treea322dc9efdd89932a35b294d221f90eccad45f23 /include/linux/syscalls.h
parentcbfe20f565228966f0249f016752437df95df679 (diff)
fs: add do_fchownat(), ksys_fchown() helpers and ksys_{,l}chown() wrappers
Using the fs-interal do_fchownat() wrapper allows us to get rid of fs-internal calls to the sys_fchownat() syscall. Introducing the ksys_fchown() helper and the ksys_{,}chown() wrappers allows us to avoid the in-kernel calls to the sys_{,l,f}chown() syscalls. The ksys_ prefix denotes that these functions are meant as a drop-in replacement for the syscalls. In particular, they use the same calling convention as sys_{,l,f}chown(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Diffstat (limited to 'include/linux/syscalls.h')
-rw-r--r--include/linux/syscalls.h17
1 files changed, 17 insertions, 0 deletions
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 33f06de090ea..df0d1e818a6e 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -954,6 +954,7 @@ int ksys_chroot(const char __user *filename);
ssize_t ksys_write(unsigned int fd, const char __user *buf, size_t count);
int ksys_chdir(const char __user *filename);
int ksys_fchmod(unsigned int fd, umode_t mode);
+int ksys_fchown(unsigned int fd, uid_t user, gid_t group);
/*
* The following kernel syscall equivalents are just wrappers to fs-internal
@@ -1021,4 +1022,20 @@ static inline long ksys_access(const char __user *filename, int mode)
return do_faccessat(AT_FDCWD, filename, mode);
}
+extern int do_fchownat(int dfd, const char __user *filename, uid_t user,
+ gid_t group, int flag);
+
+static inline long ksys_chown(const char __user *filename, uid_t user,
+ gid_t group)
+{
+ return do_fchownat(AT_FDCWD, filename, user, group, 0);
+}
+
+static inline long ksys_lchown(const char __user *filename, uid_t user,
+ gid_t group)
+{
+ return do_fchownat(AT_FDCWD, filename, user, group,
+ AT_SYMLINK_NOFOLLOW);
+}
+
#endif