Re: [PATCH v5.1] fs: Allow fine-grained control of folio sizes
From: Pankaj Raghav (Samsung) <hidden>
Date: 2024-05-27 22:09:34
Also in:
linux-fsdevel, linux-mm, linux-xfs
On Mon, May 27, 2024 at 10:01:23PM +0100, Matthew Wilcox (Oracle) wrote:
We need filesystems to be able to communicate acceptable folio sizes to the pagecache for a variety of uses (e.g. large block sizes). Support a range of folio sizes between order-0 and order-31. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Co-developed-by: Pankaj Raghav <redacted> Signed-off-by: Pankaj Raghav <redacted> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> --- For this version, I fixed the TODO that the maximum folio size was not being honoured. I made some other changes too like adding const, moving the location of the constants, checking CONFIG_TRANSPARENT_HUGEPAGE, and dropping some of the functions which aren't needed until later patches. (They can be added in the commits that need them). Also rebased against current Linus tree, so MAX_PAGECACHE_ORDER no longer needs to be moved).
Thanks for this! So I am currently running my xfstests on the new series I am planning to send in a day or two based on next-20240523. I assume this patch is intended to be folded in to the next LBS series?
quoted hunk ↗ jump to hunk
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 1ed9274a0deb..c6aaceed0de6 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h@@ -204,13 +204,18 @@ enum mapping_flags { AS_EXITING = 4, /* final truncate in progress */ /* writeback related tags are not used */ AS_NO_WRITEBACK_TAGS = 5, - AS_LARGE_FOLIO_SUPPORT = 6, - AS_RELEASE_ALWAYS, /* Call ->release_folio(), even if no private data */ - AS_STABLE_WRITES, /* must wait for writeback before modifying + AS_RELEASE_ALWAYS = 6, /* Call ->release_folio(), even if no private data */ + AS_STABLE_WRITES = 7, /* must wait for writeback before modifying folio contents */ - AS_UNMOVABLE, /* The mapping cannot be moved, ever */ + AS_UNMOVABLE = 8, /* The mapping cannot be moved, ever */ + AS_FOLIO_ORDER_MIN = 16, + AS_FOLIO_ORDER_MAX = 21, /* Bits 16-25 are used for FOLIO_ORDER */ }; +#define AS_FOLIO_ORDER_MIN_MASK 0x001f0000 +#define AS_FOLIO_ORDER_MAX_MASK 0x03e00000
As you changed the mapping flag offset, these masks also needs to be changed accordingly. I moved(pun intended) the AS_UNMOVABLE and kept the AS_FOLIO_ORDER_(MIN|MAX) value the same. AS_FOLIO_ORDER_MIN = 8, AS_FOLIO_ORDER_MAX = 13, /* Bit 8-17 are used for FOLIO_ORDER */ AS_UNMOVABLE = 18, /* The mapping cannot be moved, ever */ AS_INACCESSIBLE, /* Do not attempt direct R/W access to the mapping */
+#define AS_FOLIO_ORDER_MASK (AS_FOLIO_ORDER_MIN_MASK | AS_FOLIO_ORDER_MAX_MASK) +
-- Pankaj