The patch titled
Subject: filemap: add a kiocb_invalidate_pages helper
has been added to the -mm mm-unstable branch. Its filename is
filemap-add-a-kiocb_invalidate_pages-helper.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/filemap-add-a-kiocb_invalidate_pages-helper.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: Christoph Hellwig <hch@xxxxxx>
Subject: filemap: add a kiocb_invalidate_pages helper
Date: Fri, 19 May 2023 11:35:13 +0200
Factor out a helper that calls filemap_write_and_wait_range and
invalidate_inode_pages2_rangefor a the range covered by a write kiocb or
returns -EAGAIN if the kiocb is marked as nowait and there would be pages
to write or invalidate.
Link: https://lkml.kernel.org/r/20230519093521.133226-6-hch@xxxxxx
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
Cc: Anna Schumaker <anna@xxxxxxxxxx>
Cc: Chao Yu <chao@xxxxxxxxxx>
Cc: Christian Brauner <brauner@xxxxxxxxxx>
Cc: Damien Le Moal <dlemoal@xxxxxxxxxx>
Cc: Darrick J. Wong <djwong@xxxxxxxxxx>
Cc: Ilya Dryomov <idryomov@xxxxxxxxx>
Cc: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Miklos Szeredi <miklos@xxxxxxxxxx>
Cc: Theodore Ts'o <tytso@xxxxxxx>
Cc: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Cc: Xiubo Li <xiubli@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/pagemap.h | 1
mm/filemap.c | 48 ++++++++++++++++++++++----------------
2 files changed, 29 insertions(+), 20 deletions(-)
--- a/include/linux/pagemap.h~filemap-add-a-kiocb_invalidate_pages-helper
+++ a/include/linux/pagemap.h
@@ -30,6 +30,7 @@ static inline void invalidate_remote_ino
int invalidate_inode_pages2(struct address_space *mapping);
int invalidate_inode_pages2_range(struct address_space *mapping,
pgoff_t start, pgoff_t end);
+int kiocb_invalidate_pages(struct kiocb *iocb, size_t count);
int write_inode_now(struct inode *, int sync);
int filemap_fdatawrite(struct address_space *);
--- a/mm/filemap.c~filemap-add-a-kiocb_invalidate_pages-helper
+++ a/mm/filemap.c
@@ -2750,6 +2750,33 @@ int kiocb_write_and_wait(struct kiocb *i
return filemap_write_and_wait_range(mapping, pos, end);
}
+int kiocb_invalidate_pages(struct kiocb *iocb, size_t count)
+{
+ struct address_space *mapping = iocb->ki_filp->f_mapping;
+ loff_t pos = iocb->ki_pos;
+ loff_t end = pos + count - 1;
+ int ret;
+
+ if (iocb->ki_flags & IOCB_NOWAIT) {
+ /* we could block if there are any pages in the range */
+ if (filemap_range_has_page(mapping, pos, end))
+ return -EAGAIN;
+ } else {
+ ret = filemap_write_and_wait_range(mapping, pos, end);
+ if (ret)
+ return ret;
+ }
+
+ /*
+ * After a write we want buffered reads to be sure to go to disk to get
+ * the new data. We invalidate clean cached page from the region we're
+ * about to write. We do this *before* the write so that we can return
+ * without clobbering -EIOCBQUEUED from ->direct_IO().
+ */
+ return invalidate_inode_pages2_range(mapping, pos >> PAGE_SHIFT,
+ end >> PAGE_SHIFT);
+}
+
/**
* generic_file_read_iter - generic filesystem read routine
* @iocb: kernel I/O control block
@@ -3793,30 +3820,11 @@ generic_file_direct_write(struct kiocb *
write_len = iov_iter_count(from);
end = (pos + write_len - 1) >> PAGE_SHIFT;
- if (iocb->ki_flags & IOCB_NOWAIT) {
- /* If there are pages to writeback, return */
- if (filemap_range_has_page(file->f_mapping, pos,
- pos + write_len - 1))
- return -EAGAIN;
- } else {
- written = filemap_write_and_wait_range(mapping, pos,
- pos + write_len - 1);
- if (written)
- goto out;
- }
-
- /*
- * After a write we want buffered reads to be sure to go to disk to get
- * the new data. We invalidate clean cached page from the region we're
- * about to write. We do this *before* the write so that we can return
- * without clobbering -EIOCBQUEUED from ->direct_IO().
- */
- written = invalidate_inode_pages2_range(mapping,
- pos >> PAGE_SHIFT, end);
/*
* If a page can not be invalidated, return 0 to fall back
* to buffered write.
*/
+ written = kiocb_invalidate_pages(iocb, write_len);
if (written) {
if (written == -EBUSY)
return 0;
_
Patches currently in -mm which might be from hch@xxxxxx are
iomap-update-ki_pos-a-little-later-in-iomap_dio_complete.patch
filemap-update-ki_pos-in-generic_perform_write.patch
filemap-assign-current-backing_dev_info-in-generic_perform_write.patch
filemap-add-a-kiocb_write_and_wait-helper.patch
filemap-add-a-kiocb_invalidate_pages-helper.patch
filemap-add-a-kiocb_invalidate_post_write-helper.patch
iomap-update-ki_pos-in-iomap_file_buffered_write.patch
iomap-assign-current-backing_dev_info-in-iomap_file_buffered_write.patch
iomap-use-kiocb_write_and_wait-and-kiocb_invalidate_pages.patch
fs-factor-out-a-direct_write_fallback-helper.patch
fuse-update-ki_pos-in-fuse_perform_write.patch
fuse-drop-redundant-arguments-to-fuse_perform_write.patch
fuse-use-direct_write_fallback.patch
squashfs-dont-include-buffer_headh.patch
