Commit cceba6f7 authored by Jens Axboe's avatar Jens Axboe Committed by Andrew Morton
Browse files

mm: add PG_dropbehind folio flag 

Add a folio flag that file IO can use to indicate that the cached IO being
done should be dropped from the page cache upon completion.

Link: https://lkml.kernel.org/r/20241220154831.1086649-5-axboe@kernel.dk


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
Reviewed-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Brian Foster <bfoster@redhat.com>
Cc: Chris Mason <clm@meta.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 1963de79

include/linux/page-flags.h

+5 −0
Original line number Diff line number Diff line
@@ -110,6 +110,7 @@ enum pageflags { 
	PG_reclaim,		/* To be reclaimed asap */

	PG_swapbacked,		/* Page is backed by RAM/swap */

	PG_unevictable,		/* Page is "unevictable"  */

	PG_dropbehind,		/* drop pages on IO completion */

#ifdef CONFIG_MMU

	PG_mlocked,		/* Page is vma mlocked */

#endif
@@ -562,6 +563,10 @@ PAGEFLAG(Reclaim, reclaim, PF_NO_TAIL) 
FOLIO_FLAG(readahead, FOLIO_HEAD_PAGE)

	FOLIO_TEST_CLEAR_FLAG(readahead, FOLIO_HEAD_PAGE)



FOLIO_FLAG(dropbehind, FOLIO_HEAD_PAGE)

	FOLIO_TEST_CLEAR_FLAG(dropbehind, FOLIO_HEAD_PAGE)

	__FOLIO_SET_FLAG(dropbehind, FOLIO_HEAD_PAGE)



#ifdef CONFIG_HIGHMEM

/*

 * Must use a macro here due to header dependency issues. page_zone() is not

include/trace/events/mmflags.h

+2 −1
Original line number Diff line number Diff line
@@ -116,7 +116,8 @@ 
	DEF_PAGEFLAG_NAME(head),					\

	DEF_PAGEFLAG_NAME(reclaim),					\

	DEF_PAGEFLAG_NAME(swapbacked),					\

	DEF_PAGEFLAG_NAME(unevictable)					\

	DEF_PAGEFLAG_NAME(unevictable),					\

	DEF_PAGEFLAG_NAME(dropbehind)					\

IF_HAVE_PG_MLOCK(mlocked)						\

IF_HAVE_PG_HWPOISON(hwpoison)						\

IF_HAVE_PG_IDLE(idle)							\