The patch titled
Subject: fs/dax: refactor wait for dax idle page
has been added to the -mm mm-unstable branch. Its filename is
fs-dax-refactor-wait-for-dax-idle-page.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/fs-dax-refactor-wait-for-dax-idle-page.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Alistair Popple <apopple@xxxxxxxxxx>
Subject: fs/dax: refactor wait for dax idle page
Date: Wed, 5 Feb 2025 09:48:01 +1100
A FS DAX page is considered idle when its refcount drops to one. This is
currently open-coded in all file systems supporting FS DAX. Move the idle
detection to a common function to make future changes easier.
Link: https://lkml.kernel.org/r/8e6f61482cd0c0be1750ecd5b7412fbfab414e49.1738709036.git-series.apopple@xxxxxxxxxx
Signed-off-by: Alistair Popple <apopple@xxxxxxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Acked-by: Theodore Ts'o <tytso@xxxxxxx>
Tested-by: Alison Schofield <alison.schofield@xxxxxxxxx>
Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Cc: Asahi Lina <lina@xxxxxxxxxxxxx>
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx>
Cc: Chunyan Zhang <zhang.lyra@xxxxxxxxx>
Cc: "Darrick J. Wong" <djwong@xxxxxxxxxx>
Cc: Dave Chinner <david@xxxxxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Dave Jiang <dave.jiang@xxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Gerald Schaefer <gerald.schaefer@xxxxxxxxxxxxx>
Cc: Heiko Carstens <hca@xxxxxxxxxxxxx>
Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: linmiaohe <linmiaohe@xxxxxxxxxx>
Cc: Logan Gunthorpe <logang@xxxxxxxxxxxx>
Cc: Mattew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Peter Xu <peterx@xxxxxxxxxx>
Cc: Sven Schnelle <svens@xxxxxxxxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Cc: Vivek Goyal <vgoyal@xxxxxxxxxx>
Cc: WANG Xuerui <kernel@xxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/ext4/inode.c | 5 +----
fs/fuse/dax.c | 4 +---
fs/xfs/xfs_inode.c | 4 +---
include/linux/dax.h | 8 ++++++++
4 files changed, 11 insertions(+), 10 deletions(-)
--- a/fs/ext4/inode.c~fs-dax-refactor-wait-for-dax-idle-page
+++ a/fs/ext4/inode.c
@@ -3922,10 +3922,7 @@ int ext4_break_layouts(struct inode *ino
if (!page)
return 0;
- error = ___wait_var_event(&page->_refcount,
- atomic_read(&page->_refcount) == 1,
- TASK_INTERRUPTIBLE, 0, 0,
- ext4_wait_dax_page(inode));
+ error = dax_wait_page_idle(page, ext4_wait_dax_page, inode);
} while (error == 0);
return error;
--- a/fs/fuse/dax.c~fs-dax-refactor-wait-for-dax-idle-page
+++ a/fs/fuse/dax.c
@@ -677,9 +677,7 @@ static int __fuse_dax_break_layouts(stru
return 0;
*retry = true;
- return ___wait_var_event(&page->_refcount,
- atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE,
- 0, 0, fuse_wait_dax_page(inode));
+ return dax_wait_page_idle(page, fuse_wait_dax_page, inode);
}
int fuse_dax_break_layouts(struct inode *inode, u64 dmap_start,
--- a/fs/xfs/xfs_inode.c~fs-dax-refactor-wait-for-dax-idle-page
+++ a/fs/xfs/xfs_inode.c
@@ -3017,9 +3017,7 @@ xfs_break_dax_layouts(
return 0;
*retry = true;
- return ___wait_var_event(&page->_refcount,
- atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE,
- 0, 0, xfs_wait_dax_page(inode));
+ return dax_wait_page_idle(page, xfs_wait_dax_page, inode);
}
int
--- a/include/linux/dax.h~fs-dax-refactor-wait-for-dax-idle-page
+++ a/include/linux/dax.h
@@ -207,6 +207,14 @@ int dax_zero_range(struct inode *inode,
int dax_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
const struct iomap_ops *ops);
+static inline int dax_wait_page_idle(struct page *page,
+ void (cb)(struct inode *),
+ struct inode *inode)
+{
+ return ___wait_var_event(page, page_ref_count(page) == 1,
+ TASK_INTERRUPTIBLE, 0, 0, cb(inode));
+}
+
#if IS_ENABLED(CONFIG_DAX)
int dax_read_lock(void);
void dax_read_unlock(int id);
_
Patches currently in -mm which might be from apopple@xxxxxxxxxx are
fuse-fix-dax-truncate-punch_hole-fault-path.patch
fs-dax-return-unmapped-busy-pages-from-dax_layout_busy_page_range.patch
fs-dax-dont-skip-locked-entries-when-scanning-entries.patch
fs-dax-refactor-wait-for-dax-idle-page.patch
fs-dax-create-a-common-implementation-to-break-dax-layouts.patch
fs-dax-always-remove-dax-page-cache-entries-when-breaking-layouts.patch
fs-dax-ensure-all-pages-are-idle-prior-to-filesystem-unmount.patch
fs-dax-remove-page_mapping_dax_shared-mapping-flag.patch
mm-gup-remove-redundant-check-for-pci-p2pdma-page.patch
mm-mm_init-move-p2pdma-page-refcount-initialisation-to-p2pdma.patch
mm-allow-compound-zone-device-pages.patch
mm-memory-enhance-insert_page_into_pte_locked-to-create-writable-mappings.patch
mm-memory-add-vmf_insert_page_mkwrite.patch
rmap-add-support-for-pud-sized-mappings-to-rmap.patch
huge_memory-add-vmf_insert_folio_pud.patch
huge_memory-add-vmf_insert_folio_pmd.patch
mm-gup-dont-allow-foll_longterm-pinning-of-fs-dax-pages.patch
fs-dax-properly-refcount-fs-dax-pages.patch
device-dax-properly-refcount-device-dax-pages-when-mapping.patch
