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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 (3.56.2-2.fc42) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Sat, 2026-05-23 at 17:58 +0200, David Sterba wrote: > On Wed, May 20, 2026 at 10:47:49AM -0700, Boris Burkov wrote: > > > @@ -689,14 +704,23 @@ int btrfs_alloc_page_array(unsigned int > > > nr_pages, struct page **page_array, > > > =C2=A0 * Populate needed folios for the extent buffer. > > > =C2=A0 * > > > =C2=A0 * For now, the folios populated are always in order 0 (aka, > > > single page). > > > + * > > > + * @movable: pass true only when the resulting pages will be > > > attached to > > > + *=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 btree= _inode->i_mapping (the alloc_extent_buffer > > > real path). > > > + *=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 Clone= d/dummy extent buffers > > > (EXTENT_BUFFER_UNMAPPED) leave > > > + *=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 folio= ->mapping NULL, never enter the LRU, and never > > > get the > > > + *=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 btree= _migrate_folio aops, so __GFP_MOVABLE would > > > violate the > > > + *=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 page-= allocator's migrability contract for them. > > > =C2=A0 */ > >=20 > > My gut says it is nicer to just transparently pass along a gfp flag > > rather than a carefully documented movable boolean and let the > > callers > > do the right thing. Just a nit, I don't care strongly about it. >=20 > Agreed, the GFP flags would be better and also a bit more self > documenting where the functions are called. The patch is not > standalone > so I don't mind having the booleans, we can clean it up later to let > the > 40-patch series proceed. I think this patch could go in by itself. It doesn't depend on anything else in the series. I sent it with this series mostly because it's needed to make the series work, and to provide context on why it's needed. I'm happy to resend it with a GFP mask passed in by each caller. That would look better, indeed! I'll send you guys a cleaned up patch this coming week. --=20 All Rights Reversed.