Hi Bernd,
On 7/5/23 18:23, Bernd Schubert wrote:
From: Bernd Schubert <bschubert@xxxxxxx>
In commit 153524053bbb0d27bb2e0be36d1b46862e9ce74c DIO
writes can be handled in parallel, as long as the file
is not extended. So far this only works when daemon/server
side set FOPEN_DIRECT_IO and FOPEN_PARALLEL_DIRECT_WRITES,
but O_DIRECT (iocb->ki_flags & IOCB_DIRECT) went another
code path that doesn't have the parallel DIO write
optimization.
Given that fuse_direct_write_iter has to handle page writes
and invalidation anyway (for mmap), the DIO handler in
fuse_cache_write_iter() is removed and DIO writes are now
only handled by fuse_direct_write_iter().
Note: Correctness of this patch depends on a non-merged
series from Hao Xu <hao.xu@xxxxxxxxx>
( fuse: add a new fuse init flag to relax restrictions in no cache mode)
---
fs/fuse/file.c | 38 +++++---------------------------------
1 file changed, 5 insertions(+), 33 deletions(-)
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 89d97f6188e0..1490329b536c 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1337,11 +1337,9 @@ static ssize_t fuse_cache_write_iter(struct kiocb
*iocb, struct iov_iter *from)
struct file *file = iocb->ki_filp;
struct address_space *mapping = file->f_mapping;
ssize_t written = 0;
- ssize_t written_buffered = 0;
struct inode *inode = mapping->host;
ssize_t err;
struct fuse_conn *fc = get_fuse_conn(inode);
- loff_t endbyte = 0;
if (fc->writeback_cache) {
/* Update size (EOF optimization) and mode (SUID clearing) */
@@ -1377,37 +1375,10 @@ static ssize_t fuse_cache_write_iter(struct
kiocb *iocb, struct iov_iter *from)
if (err)
goto out;
- if (iocb->ki_flags & IOCB_DIRECT) {
- loff_t pos = iocb->ki_pos;
- written = generic_file_direct_write(iocb, from);
- if (written < 0 || !iov_iter_count(from))
- goto out;
-
- pos += written;
-
- written_buffered = fuse_perform_write(iocb, mapping, from, pos);
- if (written_buffered < 0) {
- err = written_buffered;
- goto out;
- }
- endbyte = pos + written_buffered - 1;
-
- err = filemap_write_and_wait_range(file->f_mapping, pos,
- endbyte);
- if (err)
- goto out;
-
- invalidate_mapping_pages(file->f_mapping,
- pos >> PAGE_SHIFT,
- endbyte >> PAGE_SHIFT);
+ written = fuse_perform_write(iocb, mapping, from, iocb->ki_pos);
+ if (written >= 0)
+ iocb->ki_pos += written;
- written += written_buffered;
- iocb->ki_pos = pos + written_buffered;
- } else {
- written = fuse_perform_write(iocb, mapping, from, iocb->ki_pos);
- if (written >= 0)
- iocb->ki_pos += written;
- }
out:
current->backing_dev_info = NULL;
inode_unlock(inode);
@@ -1691,7 +1662,8 @@ static ssize_t fuse_file_write_iter(struct kiocb
*iocb, struct iov_iter *from)
if (FUSE_IS_DAX(inode))
return fuse_dax_write_iter(iocb, from);
- if (!(ff->open_flags & FOPEN_DIRECT_IO))
+ if (!(ff->open_flags & FOPEN_DIRECT_IO) &&
+ !(iocb->ki_flags & IOCB_DIRECT))
return fuse_cache_write_iter(iocb, from);
else
return fuse_direct_write_iter(iocb, from);
For normal direct io(IOCB_DIRECT set, FOPEN_DIRECT_IO not set), it now
goes to fuse_direct_write_iter() but the thing is the previous patchset
I sent adds page flush and invalidation in FOPEN_DIRECT_IO
and/or fc->direct_io_relax, so I guess this part(flush and invalidation)
is not included in the normal direct io code path.
Regards,
Hao
