Better permission handling, add chmod/chown

include/sys/amd64/sys_file.h

@@ -22,3 +22,6 @@ int sys_access(const char *path, int mode);
 
 // TODO: const struct termios *termp, const struct winsize *winp
 int sys_openpty(int *master, int *slave);
+
+int sys_chmod(const char *path, mode_t mode);
+int sys_chown(const char *path, uid_t uid, gid_t gid);

include/sys/fs/node.h

@@ -45,6 +45,8 @@ struct vnode_operations {
 
     int (*stat) (struct vnode *at, struct stat *st);
     int (*access) (struct vnode *node, uid_t *uid, gid_t *gid, mode_t *mode);
+    int (*chmod) (struct vnode *node, mode_t mode);
+    int (*chown) (struct vnode *node, uid_t uid, gid_t gid);
 
     int (*readlink) (struct vnode *at, char *buf, size_t lim);
 

include/sys/fs/vfs.h

@@ -39,6 +39,8 @@ int vfs_readdir(struct vfs_ioctx *ctx, struct ofile *fd, struct dirent *ent);
 int vfs_unlink(struct vfs_ioctx *ctx, const char *path);
 int vfs_rmdir(struct vfs_ioctx *ctx, const char *path);
 int vfs_mkdir(struct vfs_ioctx *ctx, const char *path, mode_t mode);
+int vfs_chmod(struct vfs_ioctx *ctx, const char *path, mode_t mode);
+int vfs_chown(struct vfs_ioctx *ctx, const char *path, uid_t uid, gid_t gid);
 
 int vfs_access(struct vfs_ioctx *ctx, const char *path, int accmode);
 int vfs_stat(struct vfs_ioctx *ctx, const char *path, struct stat *st);

include/sys/syscall.h

@@ -13,6 +13,8 @@
 #define SYSCALL_NR_CREAT        85
 #define SYSCALL_NR_UNLINK       87
 #define SYSCALL_NR_READDIR      89
+#define SYSCALL_NR_CHMOD        90
+#define SYSCALL_NR_CHOWN        92
 
 #define SYSCALL_NR_BRK          12
 #define SYSCALL_NR_NANOSLEEP    35