Commit 0c949334 authored by Al Viro's avatar Al Viro
Browse files

iov_iter_truncate() 



Now It Can Be Done(tm) - we don't need to do iov_shorten() in
generic_file_direct_write() anymore, now that all ->direct_IO()
instances are converted to proper iov_iter methods and honour
iter->count and iter->iov_offset properly.

Get rid of count/ocount arguments of generic_file_direct_write(),
while we are at it.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 28060d5d

fs/btrfs/file.c

+8 −9
Original line number Diff line number Diff line
@@ -1659,8 +1659,7 @@ again: 


static ssize_t __btrfs_direct_write(struct kiocb *iocb,

				    struct iov_iter *from,

				    loff_t pos,

				    size_t count, size_t ocount)

				    loff_t pos)

{

	struct file *file = iocb->ki_filp;

	ssize_t written;
@@ -1668,9 +1667,9 @@ static ssize_t __btrfs_direct_write(struct kiocb *iocb, 
	loff_t endbyte;

	int err;



	written = generic_file_direct_write(iocb, from, pos, count, ocount);

	written = generic_file_direct_write(iocb, from, pos);



	if (written < 0 || written == count)

	if (written < 0 || !iov_iter_count(from))

		return written;



	pos += written;
@@ -1720,13 +1719,14 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb, 
	u64 end_pos;

	ssize_t num_written = 0;

	ssize_t err = 0;

	size_t count, ocount;

	size_t count;

	bool sync = (file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host);

	struct iov_iter i;



	mutex_lock(&inode->i_mutex);



	count = ocount = iov_length(iov, nr_segs);

	count = iov_length(iov, nr_segs);

	iov_iter_init(&i, WRITE, iov, nr_segs, count);



	current->backing_dev_info = inode->i_mapping->backing_dev_info;

	err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
@@ -1740,7 +1740,7 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb, 
		goto out;

	}



	iov_iter_init(&i, WRITE, iov, nr_segs, count);

	iov_iter_truncate(&i, count);



	err = file_remove_suid(file);

	if (err) {
@@ -1783,8 +1783,7 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb, 
		atomic_inc(&BTRFS_I(inode)->sync_writers);



	if (unlikely(file->f_flags & O_DIRECT)) {

		num_written = __btrfs_direct_write(iocb, &i,

						   pos, count, ocount);

		num_written = __btrfs_direct_write(iocb, &i, pos);

	} else {

		num_written = __btrfs_buffered_write(file, &i, pos);

		if (num_written > 0)

fs/fuse/file.c

+8 −10
Original line number Diff line number Diff line
@@ -1188,8 +1188,7 @@ static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 
{

	struct file *file = iocb->ki_filp;

	struct address_space *mapping = file->f_mapping;

	size_t count = 0;

	size_t ocount = 0;

	size_t count;

	ssize_t written = 0;

	ssize_t written_buffered = 0;

	struct inode *inode = mapping->host;
@@ -1208,7 +1207,8 @@ static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 


	WARN_ON(iocb->ki_pos != pos);



	count = ocount = iov_length(iov, nr_segs);

	count = iov_length(iov, nr_segs);

	iov_iter_init(&i, WRITE, iov, nr_segs, count);

	mutex_lock(&inode->i_mutex);



	/* We can write back this queue in page reclaim */
@@ -1217,11 +1217,11 @@ static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 
	err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));

	if (err)

		goto out;

	iov_iter_init(&i, WRITE, iov, nr_segs, count);



	if (count == 0)

		goto out;



	iov_iter_truncate(&i, count);

	err = file_remove_suid(file);

	if (err)

		goto out;
@@ -1231,8 +1231,8 @@ static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 
		goto out;



	if (file->f_flags & O_DIRECT) {

		written = generic_file_direct_write(iocb, &i, pos, count, ocount);

		if (written < 0 || written == count)

		written = generic_file_direct_write(iocb, &i, pos);

		if (written < 0 || !iov_iter_count(&i))

			goto out;



		pos += written;
@@ -1469,8 +1469,7 @@ static ssize_t __fuse_direct_write(struct fuse_io_priv *io, 


	res = generic_write_checks(file, ppos, &count, 0);

	if (!res) {

		if (iter->count > count)

			iter->count = count;

		iov_iter_truncate(iter, count);

		res = fuse_direct_io(io, iter, ppos, FUSE_DIO_WRITE);

	}
@@ -2896,8 +2895,7 @@ fuse_direct_IO(int rw, struct kiocb *iocb, struct iov_iter *iter, 
		if (offset >= i_size)

			return 0;

		count = min_t(loff_t, count, fuse_round_up(i_size - offset));

		if (iter->count > count)

			iter->count = count;

		iov_iter_truncate(iter, count);

	}



	io = kmalloc(sizeof(struct fuse_io_priv), GFP_KERNEL);

fs/ocfs2/file.c

+5 −5
Original line number Diff line number Diff line
@@ -2241,7 +2241,6 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb, 
	int ret, direct_io, appending, rw_level, have_alloc_sem  = 0;

	int can_do_direct, has_refcount = 0;

	ssize_t written = 0;

	size_t ocount;		/* original count */

	size_t count;		/* after file limit checks */

	loff_t old_size, *ppos = &iocb->ki_pos;

	u32 old_clusters;
@@ -2253,6 +2252,9 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb, 
	int unaligned_dio = 0;

	struct iov_iter from;



	count = iov_length(iov, nr_segs);

	iov_iter_init(&from, WRITE, iov, nr_segs, count);



	trace_ocfs2_file_aio_write(inode, file, file->f_path.dentry,

		(unsigned long long)OCFS2_I(inode)->ip_blkno,

		file->f_path.dentry->d_name.len,
@@ -2355,16 +2357,14 @@ relock: 
	/* communicate with ocfs2_dio_end_io */

	ocfs2_iocb_set_rw_locked(iocb, rw_level);



	count = ocount = iov_length(iov, nr_segs);

	ret = generic_write_checks(file, ppos, &count,

				   S_ISBLK(inode->i_mode));

	if (ret)

		goto out_dio;



	iov_iter_init(&from, WRITE, iov, nr_segs, count);

	iov_iter_truncate(&from, count);

	if (direct_io) {

		written = generic_file_direct_write(iocb, &from, *ppos,

						    count, ocount);

		written = generic_file_direct_write(iocb, &from, *ppos);

		if (written < 0) {

			ret = written;

			goto out_dio;

fs/xfs/xfs_file.c

+5 −4
Original line number Diff line number Diff line
@@ -626,7 +626,7 @@ xfs_file_dio_aio_write( 
	const struct iovec	*iovp,

	unsigned long		nr_segs,

	loff_t			pos,

	size_t			ocount)

	size_t			count)

{

	struct file		*file = iocb->ki_filp;

	struct address_space	*mapping = file->f_mapping;
@@ -634,7 +634,6 @@ xfs_file_dio_aio_write( 
	struct xfs_inode	*ip = XFS_I(inode);

	struct xfs_mount	*mp = ip->i_mount;

	ssize_t			ret = 0;

	size_t			count = ocount;

	int			unaligned_io = 0;

	int			iolock;

	struct xfs_buftarg	*target = XFS_IS_REALTIME_INODE(ip) ?
@@ -645,6 +644,8 @@ xfs_file_dio_aio_write( 
	if ((pos | count) & target->bt_logical_sectormask)

		return -XFS_ERROR(EINVAL);



	iov_iter_init(&from, WRITE, iovp, nr_segs, count);



	/* "unaligned" here means not aligned to a filesystem block */

	if ((pos & mp->m_blockmask) || ((pos + count) & mp->m_blockmask))

		unaligned_io = 1;
@@ -676,6 +677,7 @@ xfs_file_dio_aio_write( 
	ret = xfs_file_aio_write_checks(file, &pos, &count, &iolock);

	if (ret)

		goto out;

	iov_iter_truncate(&from, count);



	if (mapping->nrpages) {

		ret = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
@@ -697,8 +699,7 @@ xfs_file_dio_aio_write( 
	}



	trace_xfs_file_direct_write(ip, count, iocb->ki_pos, 0);

	iov_iter_init(&from, WRITE, iovp, nr_segs, count);

	ret = generic_file_direct_write(iocb, &from, pos, count, ocount);

	ret = generic_file_direct_write(iocb, &from, pos);



out:

	xfs_rw_iunlock(ip, iolock);

include/linux/fs.h

+1 −2
Original line number Diff line number Diff line
@@ -2407,8 +2407,7 @@ extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsig 
extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);

extern ssize_t __generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long);

extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);

extern ssize_t generic_file_direct_write(struct kiocb *, struct iov_iter *,

		loff_t, size_t, size_t);

extern ssize_t generic_file_direct_write(struct kiocb *, struct iov_iter *, loff_t);

extern ssize_t generic_perform_write(struct file *, struct iov_iter *, loff_t);

extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);

extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);

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