Using this wrapper allows us to avoid the in-kernel calls to the
sys_unlink() syscall. The ksys_ prefix denotes that this function is meant
s a drop-in replacement for the syscall. In particular, it uses the same
calling convention as sys_unlink().
In the near future, all callers of ksys_unlink() should be converted to
call do_unlinkat() directly or, at least, to operate on regular kernel
pointers.
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>
ssize_t ksys_write(unsigned int fd, const char __user *buf, size_t count);
int ksys_chdir(const char __user *filename);
+/*
+ * The following kernel syscall equivalents are just wrappers to fs-internal
+ * functions. Therefore, provide stubs to be inlined at the callsites.
+ */
+extern long do_unlinkat(int dfd, struct filename *name);
+
+static inline long ksys_unlink(const char __user *pathname)
+{
+ return do_unlinkat(AT_FDCWD, getname(pathname));
+}
+
#endif
static inline int create_dev(char *name, dev_t dev)
{
- sys_unlink(name);
+ ksys_unlink(name);
return sys_mknod(name, S_IFBLK|0600, new_encode_dev(dev));
}
* mounted in the normal path.
*/
if (rd_load_image("/initrd.image") && ROOT_DEV != Root_RAM0) {
- sys_unlink("/initrd.image");
+ ksys_unlink("/initrd.image");
handle_initrd();
return true;
}
}
- sys_unlink("/initrd.image");
+ ksys_unlink("/initrd.image");
return false;
}
sys_close(out_fd);
out:
kfree(buf);
- sys_unlink("/dev/ram");
+ ksys_unlink("/dev/ram");
return res;
}
if (S_ISDIR(st.mode))
sys_rmdir(path);
else
- sys_unlink(path);
+ ksys_unlink(path);
}
}
if (S_ISDIR(st.mode))
sys_rmdir(dirp->d_name);
else
- sys_unlink(dirp->d_name);
+ ksys_unlink(dirp->d_name);
}
num -= dirp->d_reclen;