The patch titled
Subject: filemap: add a kiocb_write_and_wait helper
has been added to the -mm mm-unstable branch. Its filename is
filemap-add-a-kiocb_write_and_wait-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_write_and_wait-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_write_and_wait helper
Date: Thu, 1 Jun 2023 16:58:56 +0200
Factor out a helper that does filemap_write_and_wait_range for the range
covered by a read kiocb, or returns -EAGAIN if the kiocb is marked as
nowait and there would be pages to write.
Link: https://lkml.kernel.org/r/20230601145904.1385409-5-hch@xxxxxx
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>
Acked-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
Cc: Anna Schumaker <anna@xxxxxxxxxx>
Cc: Chao Yu <chao@xxxxxxxxxx>
Cc: Christian Brauner <brauner@xxxxxxxxxx>
Cc: Ilya Dryomov <idryomov@xxxxxxxxx>
Cc: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Miklos Szeredi <miklos@xxxxxxxxxx>
Cc: Miklos Szeredi <mszeredi@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>
---
block/fops.c | 18 +++---------------
include/linux/pagemap.h | 2 ++
mm/filemap.c | 30 ++++++++++++++++++------------
3 files changed, 23 insertions(+), 27 deletions(-)
--- a/block/fops.c~filemap-add-a-kiocb_write_and_wait-helper
+++ a/block/fops.c
@@ -576,21 +576,9 @@ static ssize_t blkdev_read_iter(struct k
goto reexpand; /* skip atime */
if (iocb->ki_flags & IOCB_DIRECT) {
- struct address_space *mapping = iocb->ki_filp->f_mapping;
-
- if (iocb->ki_flags & IOCB_NOWAIT) {
- if (filemap_range_needs_writeback(mapping, pos,
- pos + count - 1)) {
- ret = -EAGAIN;
- goto reexpand;
- }
- } else {
- ret = filemap_write_and_wait_range(mapping, pos,
- pos + count - 1);
- if (ret < 0)
- goto reexpand;
- }
-
+ ret = kiocb_write_and_wait(iocb, count);
+ if (ret < 0)
+ goto reexpand;
file_accessed(iocb->ki_filp);
ret = blkdev_direct_IO(iocb, to);
--- a/include/linux/pagemap.h~filemap-add-a-kiocb_write_and_wait-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 write_inode_now(struct inode *, int sync);
int filemap_fdatawrite(struct address_space *);
int filemap_flush(struct address_space *);
@@ -54,6 +55,7 @@ int filemap_check_errors(struct address_
void __filemap_set_wb_err(struct address_space *mapping, int err);
int filemap_fdatawrite_wbc(struct address_space *mapping,
struct writeback_control *wbc);
+int kiocb_write_and_wait(struct kiocb *iocb, size_t count);
static inline int filemap_write_and_wait(struct address_space *mapping)
{
--- a/mm/filemap.c~filemap-add-a-kiocb_write_and_wait-helper
+++ a/mm/filemap.c
@@ -2735,6 +2735,21 @@ put_folios:
}
EXPORT_SYMBOL_GPL(filemap_read);
+int kiocb_write_and_wait(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;
+
+ if (iocb->ki_flags & IOCB_NOWAIT) {
+ if (filemap_range_needs_writeback(mapping, pos, end))
+ return -EAGAIN;
+ return 0;
+ }
+
+ return filemap_write_and_wait_range(mapping, pos, end);
+}
+
/**
* generic_file_read_iter - generic filesystem read routine
* @iocb: kernel I/O control block
@@ -2770,18 +2785,9 @@ generic_file_read_iter(struct kiocb *ioc
struct address_space *mapping = file->f_mapping;
struct inode *inode = mapping->host;
- if (iocb->ki_flags & IOCB_NOWAIT) {
- if (filemap_range_needs_writeback(mapping, iocb->ki_pos,
- iocb->ki_pos + count - 1))
- return -EAGAIN;
- } else {
- retval = filemap_write_and_wait_range(mapping,
- iocb->ki_pos,
- iocb->ki_pos + count - 1);
- if (retval < 0)
- return retval;
- }
-
+ retval = kiocb_write_and_wait(iocb, count);
+ if (retval < 0)
+ return retval;
file_accessed(file);
retval = mapping->a_ops->direct_IO(iocb, iter);
_
Patches currently in -mm which might be from hch@xxxxxx are
backing_dev-remove-current-backing_dev_info.patch
iomap-update-ki_pos-a-little-later-in-iomap_dio_complete.patch
filemap-update-ki_pos-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_direct_write-helper.patch
iomap-update-ki_pos-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
