2023-05-24 06:40:47

by Christoph Hellwig

[permalink] [raw]
Subject: [PATCH 06/11] filemap: add a kiocb_invalidate_post_direct_write helper

Add a helper to invalidate page cache after a dio write.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Damien Le Moal <[email protected]>
Acked-by: Darrick J. Wong <[email protected]>
---
fs/direct-io.c | 10 ++--------
fs/iomap/direct-io.c | 12 ++----------
include/linux/fs.h | 5 -----
include/linux/pagemap.h | 1 +
mm/filemap.c | 37 ++++++++++++++++++++-----------------
5 files changed, 25 insertions(+), 40 deletions(-)

diff --git a/fs/direct-io.c b/fs/direct-io.c
index 0b380bb8a81e11..4f9069aee0fe19 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -285,14 +285,8 @@ static ssize_t dio_complete(struct dio *dio, ssize_t ret, unsigned int flags)
* zeros from unwritten extents.
*/
if (flags & DIO_COMPLETE_INVALIDATE &&
- ret > 0 && dio_op == REQ_OP_WRITE &&
- dio->inode->i_mapping->nrpages) {
- err = invalidate_inode_pages2_range(dio->inode->i_mapping,
- offset >> PAGE_SHIFT,
- (offset + ret - 1) >> PAGE_SHIFT);
- if (err)
- dio_warn_stale_pagecache(dio->iocb->ki_filp);
- }
+ ret > 0 && dio_op == REQ_OP_WRITE)
+ kiocb_invalidate_post_direct_write(dio->iocb, ret);

inode_dio_end(dio->inode);

diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 6207a59d2162e1..0795c54a745bca 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -81,7 +81,6 @@ ssize_t iomap_dio_complete(struct iomap_dio *dio)
{
const struct iomap_dio_ops *dops = dio->dops;
struct kiocb *iocb = dio->iocb;
- struct inode *inode = file_inode(iocb->ki_filp);
loff_t offset = iocb->ki_pos;
ssize_t ret = dio->error;

@@ -108,15 +107,8 @@ ssize_t iomap_dio_complete(struct iomap_dio *dio)
* ->end_io() when necessary, otherwise a racing buffer read would cache
* zeros from unwritten extents.
*/
- if (!dio->error && dio->size &&
- (dio->flags & IOMAP_DIO_WRITE) && inode->i_mapping->nrpages) {
- int err;
- err = invalidate_inode_pages2_range(inode->i_mapping,
- offset >> PAGE_SHIFT,
- (offset + dio->size - 1) >> PAGE_SHIFT);
- if (err)
- dio_warn_stale_pagecache(iocb->ki_filp);
- }
+ if (!dio->error && dio->size && (dio->flags & IOMAP_DIO_WRITE))
+ kiocb_invalidate_post_direct_write(iocb, dio->size);

inode_dio_end(file_inode(iocb->ki_filp));

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 21a98168085641..e4efc1792a877a 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2837,11 +2837,6 @@ static inline void inode_dio_end(struct inode *inode)
wake_up_bit(&inode->i_state, __I_DIO_WAKEUP);
}

-/*
- * Warn about a page cache invalidation failure diring a direct I/O write.
- */
-void dio_warn_stale_pagecache(struct file *filp);
-
extern void inode_set_flags(struct inode *inode, unsigned int flags,
unsigned int mask);

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 6e4c9ee40baa99..6ecc4aaf5e3d51 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -31,6 +31,7 @@ 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);
+void kiocb_invalidate_post_direct_write(struct kiocb *iocb, size_t count);

int write_inode_now(struct inode *, int sync);
int filemap_fdatawrite(struct address_space *);
diff --git a/mm/filemap.c b/mm/filemap.c
index a1cb01a4b8046a..ddb6f8aa86d6ca 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -3816,7 +3816,7 @@ EXPORT_SYMBOL(read_cache_page_gfp);
/*
* Warn about a page cache invalidation failure during a direct I/O write.
*/
-void dio_warn_stale_pagecache(struct file *filp)
+static void dio_warn_stale_pagecache(struct file *filp)
{
static DEFINE_RATELIMIT_STATE(_rs, 86400 * HZ, DEFAULT_RATELIMIT_BURST);
char pathname[128];
@@ -3833,19 +3833,23 @@ void dio_warn_stale_pagecache(struct file *filp)
}
}

+void kiocb_invalidate_post_direct_write(struct kiocb *iocb, size_t count)
+{
+ struct address_space *mapping = iocb->ki_filp->f_mapping;
+
+ if (mapping->nrpages &&
+ invalidate_inode_pages2_range(mapping,
+ iocb->ki_pos >> PAGE_SHIFT,
+ (iocb->ki_pos + count - 1) >> PAGE_SHIFT))
+ dio_warn_stale_pagecache(iocb->ki_filp);
+}
+
ssize_t
generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from)
{
- struct file *file = iocb->ki_filp;
- struct address_space *mapping = file->f_mapping;
- struct inode *inode = mapping->host;
- loff_t pos = iocb->ki_pos;
- ssize_t written;
- size_t write_len;
- pgoff_t end;
-
- write_len = iov_iter_count(from);
- end = (pos + write_len - 1) >> PAGE_SHIFT;
+ struct address_space *mapping = iocb->ki_filp->f_mapping;
+ size_t write_len = iov_iter_count(from);
+ ssize_t written;

/*
* If a page can not be invalidated, return 0 to fall back
@@ -3855,7 +3859,7 @@ generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from)
if (written) {
if (written == -EBUSY)
return 0;
- goto out;
+ return written;
}

written = mapping->a_ops->direct_IO(iocb, from);
@@ -3877,11 +3881,11 @@ generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from)
*
* Skip invalidation for async writes or if mapping has no pages.
*/
- if (written > 0 && mapping->nrpages &&
- invalidate_inode_pages2_range(mapping, pos >> PAGE_SHIFT, end))
- dio_warn_stale_pagecache(file);
-
if (written > 0) {
+ struct inode *inode = mapping->host;
+ loff_t pos = iocb->ki_pos;
+
+ kiocb_invalidate_post_direct_write(iocb, written);
pos += written;
write_len -= written;
if (pos > i_size_read(inode) && !S_ISBLK(inode->i_mode)) {
@@ -3892,7 +3896,6 @@ generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from)
}
if (written != -EIOCBQUEUED)
iov_iter_revert(from, write_len - iov_iter_count(from));
-out:
return written;
}
EXPORT_SYMBOL(generic_file_direct_write);
--
2.39.2



2023-05-30 07:03:10

by Hannes Reinecke

[permalink] [raw]
Subject: Re: [PATCH 06/11] filemap: add a kiocb_invalidate_post_direct_write helper

On 5/24/23 08:38, Christoph Hellwig wrote:
> Add a helper to invalidate page cache after a dio write.
>
> Signed-off-by: Christoph Hellwig <[email protected]>
> Reviewed-by: Damien Le Moal <[email protected]>
> Acked-by: Darrick J. Wong <[email protected]>
> ---
> fs/direct-io.c | 10 ++--------
> fs/iomap/direct-io.c | 12 ++----------
> include/linux/fs.h | 5 -----
> include/linux/pagemap.h | 1 +
> mm/filemap.c | 37 ++++++++++++++++++++-----------------
> 5 files changed, 25 insertions(+), 40 deletions(-)
>
Reviewed-by: Hannes Reinecke <[email protected]>

Cheers,

Hannes
--
Dr. Hannes Reinecke Kernel Storage Architect
[email protected] +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
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