On Thu, Feb 20, 2020 at 07:49:12AM -0800, Christoph Hellwig wrote: > > +/** > > + * iomap_readahead - Attempt to read pages from a file. > > + * @rac: Describes the pages to be read. > > + * @ops: The operations vector for the filesystem. > > + * > > + * This function is for filesystems to call to implement their readahead > > + * address_space operation. > > + * > > + * Context: The file is pinned by the caller, and the pages to be read are > > + * all locked and have an elevated refcount. This function will unlock > > + * the pages (once I/O has completed on them, or I/O has been determined to > > + * not be necessary). It will also decrease the refcount once the pages > > + * have been submitted for I/O. After this point, the page may be removed > > + * from the page cache, and should not be referenced. > > + */ > > Isn't the context documentation something that belongs into the aop > documentation? I've never really seen the value of duplicating this > information in method instances, as it is just bound to be out of date > rather sooner than later. I'm in two minds about it as well. There's definitely no value in providing kernel-doc for implementations of a common interface ... so rather than fixing the nilfs2 kernel-doc, I just deleted it. But this isn't just the implementation, like nilfs2_readahead() is, it's a library function for filesystems to call, so it deserves documentation. On the other hand, there's no real thought to this on the part of the filesystem; the implementation just calls this with the appropriate ops pointer. Then again, I kind of feel like we need more documentation of iomap to help filesystems convert to using it. But maybe kernel-doc isn't the mechanism to provide that.