13df3775ef
Although we have migrated extent_buffer::pages[] to folios[], we're still mostly using the folio_page() help to grab the page. This patch would do the following cleanups for metadata: - Introduce num_extent_folios() helper This is to replace most num_extent_pages() callers. - Use num_extent_folios() to iterate future large folios This allows us to use things like bio_add_folio()/bio_add_folio_nofail(), and only set the needed flags for the folio (aka the leading/tailing page), which reduces the loop iteration to 1 for large folios. - Change metadata related functions to use folio pointers Including their function name, involving: * attach_extent_buffer_page() * detach_extent_buffer_page() * page_range_has_eb() * btrfs_release_extent_buffer_pages() * btree_clear_page_dirty() * btrfs_page_inc_eb_refs() * btrfs_page_dec_eb_refs() - Change btrfs_is_subpage() to accept an address_space pointer This is to allow both page->mapping and folio->mapping to be utilized. As data is still using the old per-page code, and may keep so for a while. - Special corner case place holder for future order mismatches between extent buffer and inode filemap For now it's just a block of comments and a dead ASSERT(), no real handling yet. The subpage code would still go page, just because subpage and large folio are conflicting conditions, thus we don't need to bother subpage with higher order folios at all. Just folio_page(folio, 0) would be enough. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ minor styling tweaks ] Signed-off-by: David Sterba <dsterba@suse.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.