mm/rmap: refactor some code around lazyfree folio unmapping

Browse source

For lazyfree folio unmapping, after clearing the ptes we must abort the
operation if the folio got dirtied or it has unexpected references.

Refactor this logic into a function which will return whether we need
to abort or not.

If we abort, we restore the ptes and bail out of try_to_unmap_one.
Otherwise adjust the rss stats of the mm and jump to a label.

Also rename that label from "discard" to "finish_unmap"; the former
is appropriate in the lazyfree context, but the code following the label
is executed for other successful unmap code paths too, so 'discard' does
not sound correct for them.

No functional change intended.

Link: https://lore.kernel.org/20260730094559.418003-4-dev.jain@arm.com
Signed-off-by: Dev Jain <dev.jain@arm.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Harry Yoo <harry@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

...

This commit is contained in:

Dev Jain 2026-07-30 09:45:54 +00:00 • committed by Andrew Morton

parent d4ec557282

commit 0955037b98

1 changed files with 48 additions and 39 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

87

mm/rmap.c

View file