On Tue, Nov 14, 2023 at 03:56:50PM +0000, Matthew Wilcox wrote:
> On Tue, Nov 14, 2023 at 10:49:37AM -0500, Chuck Lever wrote:
> > -static void offset_iterate_dir(struct inode *inode, struct dir_context *ctx)
> > +static void *offset_iterate_dir(struct inode *inode, struct dir_context *ctx)
> > {
> > struct offset_ctx *so_ctx = inode->i_op->get_offset_ctx(inode);
> > XA_STATE(xas, &so_ctx->xa, ctx->pos);
> > @@ -437,7 +437,8 @@ static void offset_iterate_dir(struct inode *inode, struct dir_context *ctx)
> > while (true) {
> > dentry = offset_find_next(&xas);
> > if (!dentry)
> > - break;
> > + /* readdir has reached the current EOD */
> > + return (void *)0x10;
>
> Funny, you used the same bit pattern as ZERO_SIZE_PTR without using
> the macro ...
On purpose, it's an eye catcher because I didn't have a better idea.
It obviously worked!
> > @@ -479,7 +481,12 @@ static int offset_readdir(struct file *file, struct dir_context *ctx)
> > if (!dir_emit_dots(file, ctx))
> > return 0;
> >
> > - offset_iterate_dir(d_inode(dir), ctx);
> > + if (ctx->pos == 2)
> > + file->private_data = NULL;
> > + else if (file->private_data == (void *)0x10)
> > + return 0;
> > +
> > + file->private_data = offset_iterate_dir(d_inode(dir), ctx);
> > return 0;
> > }
>
> It might make more sense to use ERR_PTR(-ENOENT) or ERANGE or something
> that's a more understandable sentinel value?
Yes, thanks. That's a better idea.
--
Chuck Lever
