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fuse: honor iocb sync flags on write

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If the IOCB_DSYNC flag is set a sync is not being performed by
fuse_file_write_iter.

Honor IOCB_DSYNC/IOCB_SYNC by setting O_DYSNC/O_SYNC respectively in the
flags filed of the write request.

We don't need to sync data or metadata, since fuse_perform_write() does
write-through and the filesystem is responsible for updating file times.

Original patch by Vitaly Zolotusky.

Reported-by: Nate Clark <nate@neworld.us>
Cc: Vitaly Zolotusky <vitaly@unitc.com>.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This commit is contained in:
Miklos Szeredi 2017-09-12 16:57:53 +02:00
parent 5d6d3a301c
commit e1c0eecba1
3 changed files with 28 additions and 22 deletions
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4
fs/fuse/cuse.c
View file

@ -90,7 +90,7 @@ static struct list_head *cuse_conntbl_head(dev_t devt)
static ssize_t cuse_read_iter(struct kiocb *kiocb, struct iov_iter *to)
{
struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(kiocb->ki_filp);
struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(kiocb);
loff_t pos = 0;
return fuse_direct_io(&io, to, &pos, FUSE_DIO_CUSE);
@ -98,7 +98,7 @@ static ssize_t cuse_read_iter(struct kiocb *kiocb, struct iov_iter *to)
static ssize_t cuse_write_iter(struct kiocb *kiocb, struct iov_iter *from)
{
struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(kiocb->ki_filp);
struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(kiocb);
loff_t pos = 0;
/*
* No locking or generic_write_checks(), the server is

41
fs/fuse/file.c
View file

@ -645,7 +645,7 @@ static size_t fuse_async_req_send(struct fuse_conn *fc, struct fuse_req *req,
static size_t fuse_send_read(struct fuse_req *req, struct fuse_io_priv *io,
loff_t pos, size_t count, fl_owner_t owner)
{
struct file *file = io->file;
struct file *file = io->iocb->ki_filp;
struct fuse_file *ff = file->private_data;
struct fuse_conn *fc = ff->fc;
@ -707,7 +707,8 @@ static void fuse_short_read(struct fuse_req *req, struct inode *inode,
static int fuse_do_readpage(struct file *file, struct page *page)
{
struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(file);
struct kiocb iocb;
struct fuse_io_priv io;
struct inode *inode = page->mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_req *req;
@ -735,6 +736,8 @@ static int fuse_do_readpage(struct file *file, struct page *page)
req->num_pages = 1;
req->pages[0] = page;
req->page_descs[0].length = count;
init_sync_kiocb(&iocb, file);
io = (struct fuse_io_priv) FUSE_IO_PRIV_SYNC(&iocb);
num_read = fuse_send_read(req, &io, pos, count, NULL);
err = req->out.h.error;
@ -957,13 +960,18 @@ static void fuse_write_fill(struct fuse_req *req, struct fuse_file *ff,
static size_t fuse_send_write(struct fuse_req *req, struct fuse_io_priv *io,
loff_t pos, size_t count, fl_owner_t owner)
{
struct file *file = io->file;
struct kiocb *iocb = io->iocb;
struct file *file = iocb->ki_filp;
struct fuse_file *ff = file->private_data;
struct fuse_conn *fc = ff->fc;
struct fuse_write_in *inarg = &req->misc.write.in;
fuse_write_fill(req, ff, pos, count);
inarg->flags = file->f_flags;
if (iocb->ki_flags & IOCB_DSYNC)
inarg->flags |= O_DSYNC;
if (iocb->ki_flags & IOCB_SYNC)
inarg->flags |= O_SYNC;
if (owner != NULL) {
inarg->write_flags |= FUSE_WRITE_LOCKOWNER;
inarg->lock_owner = fuse_lock_owner_id(fc, owner);
@ -993,14 +1001,14 @@ bool fuse_write_update_size(struct inode *inode, loff_t pos)
return ret;
}
static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file,
static size_t fuse_send_write_pages(struct fuse_req *req, struct kiocb *iocb,
struct inode *inode, loff_t pos,
size_t count)
{
size_t res;
unsigned offset;
unsigned i;
struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(file);
struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb);
for (i = 0; i < req->num_pages; i++)
fuse_wait_on_page_writeback(inode, req->pages[i]->index);
@ -1100,7 +1108,7 @@ static inline unsigned fuse_wr_pages(loff_t pos, size_t len)
FUSE_MAX_PAGES_PER_REQ);
}
static ssize_t fuse_perform_write(struct file *file,
static ssize_t fuse_perform_write(struct kiocb *iocb,
struct address_space *mapping,
struct iov_iter *ii, loff_t pos)
{
@ -1133,7 +1141,7 @@ static ssize_t fuse_perform_write(struct file *file,
} else {
size_t num_written;
num_written = fuse_send_write_pages(req, file, inode,
num_written = fuse_send_write_pages(req, iocb, inode,
pos, count);
err = req->out.h.error;
if (!err) {
@ -1201,7 +1209,7 @@ static ssize_t fuse_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
pos += written;
written_buffered = fuse_perform_write(file, mapping, from, pos);
written_buffered = fuse_perform_write(iocb, mapping, from, pos);
if (written_buffered < 0) {
err = written_buffered;
goto out;
@ -1220,13 +1228,15 @@ static ssize_t fuse_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
written += written_buffered;
iocb->ki_pos = pos + written_buffered;
} else {
written = fuse_perform_write(file, mapping, from, iocb->ki_pos);
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);
if (written > 0)
written = generic_write_sync(iocb, written);
return written ? written : err;
}
@ -1317,7 +1327,7 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
{
int write = flags & FUSE_DIO_WRITE;
int cuse = flags & FUSE_DIO_CUSE;
struct file *file = io->file;
struct file *file = io->iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
struct fuse_file *ff = file->private_data;
struct fuse_conn *fc = ff->fc;
@ -1399,8 +1409,7 @@ static ssize_t __fuse_direct_read(struct fuse_io_priv *io,
loff_t *ppos)
{
ssize_t res;
struct file *file = io->file;
struct inode *inode = file_inode(file);
struct inode *inode = file_inode(io->iocb->ki_filp);
if (is_bad_inode(inode))
return -EIO;
@ -1414,15 +1423,14 @@ static ssize_t __fuse_direct_read(struct fuse_io_priv *io,
static ssize_t fuse_direct_read_iter(struct kiocb *iocb, struct iov_iter *to)
{
struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb->ki_filp);
struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb);
return __fuse_direct_read(&io, to, &iocb->ki_pos);
}
static ssize_t fuse_direct_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file_inode(file);
struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(file);
struct inode *inode = file_inode(iocb->ki_filp);
struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb);
ssize_t res;
if (is_bad_inode(inode))
@ -2871,7 +2879,6 @@ fuse_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
io->offset = offset;
io->write = (iov_iter_rw(iter) == WRITE);
io->err = 0;
io->file = file;
/*
* By default, we want to optimize all I/Os with async request
* submission to the client filesystem if supported.

5
fs/fuse/fuse_i.h
View file

@ -252,16 +252,15 @@ struct fuse_io_priv {
bool should_dirty;
int err;
struct kiocb *iocb;
struct file *file;
struct completion *done;
bool blocking;
};
#define FUSE_IO_PRIV_SYNC(f) \
#define FUSE_IO_PRIV_SYNC(i) \
{ \
.refcnt = KREF_INIT(1), \
.async = 0, \
.file = f, \
.iocb = i, \
}
/**