[readdir] introduce ->iterate(), ctx->pos, dir_emit()

New method - ->iterate(file, ctx).  That's the replacement for ->readdir();
it takes callback from ctx->actor, uses ctx->pos instead of file->f_pos and
calls dir_emit(ctx, ...) instead of filldir(data, ...).  It does *not*
update file->f_pos (or look at it, for that matter); iterate_dir() does the
update.

Note that dir_emit() takes the offset from ctx->pos (and eventually
filldir_t will lose that argument).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/compat.c b/fs/compat.c
index 2279b59e81f2..69ca1e301766 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -975,7 +975,7 @@ asmlinkage long compat_sys_getdents(unsigned int fd,
                 error = buf.error;
         lastdirent = buf.previous;
         if (lastdirent) {
-                if (put_user(f.file->f_pos, &lastdirent->d_off))
+                if (put_user(buf.ctx.pos, &lastdirent->d_off))
                         error = -EFAULT;
                 else
                         error = count - buf.count;
@@ -1062,7 +1062,7 @@ asmlinkage long compat_sys_getdents64(unsigned int fd,
                 error = buf.error;
         lastdirent = buf.previous;
         if (lastdirent) {
-                typeof(lastdirent->d_off) d_off = f.file->f_pos;
+                typeof(lastdirent->d_off) d_off = buf.ctx.pos;
                 if (__put_user_unaligned(d_off, &lastdirent->d_off))
                         error = -EFAULT;
                 else