[Ocfs2-devel] [PATCH V6 19/30] ocfs2: add support for read_iter, write_iter, and direct_IO_bvec

[Joel Becker <jlbec@evilplan.org>]

Acked-by: Joel Becker <jlbec@evilplan.org>

On Tue, Jan 29, 2013 at 10:23:32AM -0600, Dave Kleikamp wrote:
> From: Zach Brown <zab@zabbo.net>
> 
> ocfs2's .aio_read and .aio_write methods are changed to take
> iov_iter and pass it to generic functions.  Wrappers are made to pack
> the iovecs into iters and call these new functions.
> 
> Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
> Cc: Zach Brown <zab@zabbo.net>
> Cc: Mark Fasheh <mfasheh@suse.com>
> Cc: Joel Becker <jlbec@evilplan.org>
> Cc: ocfs2-devel at oss.oracle.com
> ---
>  fs/ocfs2/aops.h        |  2 +-
>  fs/ocfs2/file.c        | 53 ++++++++++++++++++++++----------------------------
>  fs/ocfs2/inode.h       |  2 --
>  fs/ocfs2/ocfs2_trace.h |  6 +++---
>  4 files changed, 27 insertions(+), 36 deletions(-)
> 
> diff --git a/fs/ocfs2/aops.h b/fs/ocfs2/aops.h
> index ffb2da3..bd0425a 100644
> --- a/fs/ocfs2/aops.h
> +++ b/fs/ocfs2/aops.h
> @@ -72,7 +72,7 @@ static inline void ocfs2_iocb_set_rw_locked(struct kiocb *iocb, int level)
>  /*
>   * Using a named enum representing lock types in terms of #N bit stored in
>   * iocb->private, which is going to be used for communication between
> - * ocfs2_dio_end_io() and ocfs2_file_aio_write/read().
> + * ocfs2_dio_end_io() and ocfs2_file_write/read_iter().
>   */
>  enum ocfs2_iocb_lock_bits {
>  	OCFS2_IOCB_RW_LOCK = 0,
> diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
> index 37d313e..94fc309 100644
> --- a/fs/ocfs2/file.c
> +++ b/fs/ocfs2/file.c
> @@ -2219,15 +2219,13 @@ out:
>  	return ret;
>  }
>  
> -static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
> -				    const struct iovec *iov,
> -				    unsigned long nr_segs,
> -				    loff_t pos)
> +static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
> +				     struct iov_iter *iter,
> +				     loff_t pos)
>  {
>  	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;
> @@ -2238,11 +2236,11 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
>  			       OCFS2_MOUNT_COHERENCY_BUFFERED);
>  	int unaligned_dio = 0;
>  
> -	trace_ocfs2_file_aio_write(inode, file, file->f_path.dentry,
> +	trace_ocfs2_file_write_iter(inode, file, file->f_path.dentry,
>  		(unsigned long long)OCFS2_I(inode)->ip_blkno,
>  		file->f_path.dentry->d_name.len,
>  		file->f_path.dentry->d_name.name,
> -		(unsigned int)nr_segs);
> +		(unsigned long long)pos);
>  
>  	if (iocb->ki_left == 0)
>  		return 0;
> @@ -2344,28 +2342,24 @@ relock:
>  	/* communicate with ocfs2_dio_end_io */
>  	ocfs2_iocb_set_rw_locked(iocb, rw_level);
>  
> -	ret = generic_segment_checks(iov, &nr_segs, &ocount,
> -				     VERIFY_READ);
> -	if (ret)
> -		goto out_dio;
>  
> -	count = ocount;
> +	count = iov_iter_count(iter);
>  	ret = generic_write_checks(file, ppos, &count,
>  				   S_ISBLK(inode->i_mode));
>  	if (ret)
>  		goto out_dio;
>  
>  	if (direct_io) {
> -		written = generic_file_direct_write(iocb, iov, &nr_segs, *ppos,
> -						    ppos, count, ocount);
> +		written = generic_file_direct_write_iter(iocb, iter, *ppos,
> +						    ppos, count);
>  		if (written < 0) {
>  			ret = written;
>  			goto out_dio;
>  		}
>  	} else {
>  		current->backing_dev_info = file->f_mapping->backing_dev_info;
> -		written = generic_file_buffered_write(iocb, iov, nr_segs, *ppos,
> -						      ppos, count, 0);
> +		written = generic_file_buffered_write_iter(iocb, iter, *ppos,
> +							   ppos, count, 0);
>  		current->backing_dev_info = NULL;
>  	}
>  
> @@ -2524,7 +2518,7 @@ static ssize_t ocfs2_file_splice_read(struct file *in,
>  			in->f_path.dentry->d_name.name, len);
>  
>  	/*
> -	 * See the comment in ocfs2_file_aio_read()
> +	 * See the comment in ocfs2_file_read_iter()
>  	 */
>  	ret = ocfs2_inode_lock_atime(inode, in->f_vfsmnt, &lock_level);
>  	if (ret < 0) {
> @@ -2539,19 +2533,18 @@ bail:
>  	return ret;
>  }
>  
> -static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
> -				   const struct iovec *iov,
> -				   unsigned long nr_segs,
> +static ssize_t ocfs2_file_read_iter(struct kiocb *iocb,
> +				   struct iov_iter *iter,
>  				   loff_t pos)
>  {
>  	int ret = 0, rw_level = -1, have_alloc_sem = 0, lock_level = 0;
>  	struct file *filp = iocb->ki_filp;
>  	struct inode *inode = filp->f_path.dentry->d_inode;
>  
> -	trace_ocfs2_file_aio_read(inode, filp, filp->f_path.dentry,
> +	trace_ocfs2_file_read_iter(inode, filp, filp->f_path.dentry,
>  			(unsigned long long)OCFS2_I(inode)->ip_blkno,
>  			filp->f_path.dentry->d_name.len,
> -			filp->f_path.dentry->d_name.name, nr_segs);
> +			filp->f_path.dentry->d_name.name, pos);
>  
>  
>  	if (!inode) {
> @@ -2587,7 +2580,7 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
>  	 *
>  	 * Take and drop the meta data lock to update inode fields
>  	 * like i_size. This allows the checks down below
> -	 * generic_file_aio_read() a chance of actually working.
> +	 * generic_file_read_iter() a chance of actually working.
>  	 */
>  	ret = ocfs2_inode_lock_atime(inode, filp->f_vfsmnt, &lock_level);
>  	if (ret < 0) {
> @@ -2596,13 +2589,13 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
>  	}
>  	ocfs2_inode_unlock(inode, lock_level);
>  
> -	ret = generic_file_aio_read(iocb, iov, nr_segs, iocb->ki_pos);
> -	trace_generic_file_aio_read_ret(ret);
> +	ret = generic_file_read_iter(iocb, iter, iocb->ki_pos);
> +	trace_generic_file_read_iter_ret(ret);
>  
>  	/* buffered aio wouldn't have proper lock coverage today */
>  	BUG_ON(ret == -EIOCBQUEUED && !(filp->f_flags & O_DIRECT));
>  
> -	/* see ocfs2_file_aio_write */
> +	/* see ocfs2_file_write_iter */
>  	if (ret == -EIOCBQUEUED || !ocfs2_iocb_is_rw_locked(iocb)) {
>  		rw_level = -1;
>  		have_alloc_sem = 0;
> @@ -2700,8 +2693,8 @@ const struct file_operations ocfs2_fops = {
>  	.fsync		= ocfs2_sync_file,
>  	.release	= ocfs2_file_release,
>  	.open		= ocfs2_file_open,
> -	.aio_read	= ocfs2_file_aio_read,
> -	.aio_write	= ocfs2_file_aio_write,
> +	.read_iter	= ocfs2_file_read_iter,
> +	.write_iter	= ocfs2_file_write_iter,
>  	.unlocked_ioctl	= ocfs2_ioctl,
>  #ifdef CONFIG_COMPAT
>  	.compat_ioctl   = ocfs2_compat_ioctl,
> @@ -2748,8 +2741,8 @@ const struct file_operations ocfs2_fops_no_plocks = {
>  	.fsync		= ocfs2_sync_file,
>  	.release	= ocfs2_file_release,
>  	.open		= ocfs2_file_open,
> -	.aio_read	= ocfs2_file_aio_read,
> -	.aio_write	= ocfs2_file_aio_write,
> +	.read_iter	= ocfs2_file_read_iter,
> +	.write_iter	= ocfs2_file_write_iter,
>  	.unlocked_ioctl	= ocfs2_ioctl,
>  #ifdef CONFIG_COMPAT
>  	.compat_ioctl   = ocfs2_compat_ioctl,
> diff --git a/fs/ocfs2/inode.h b/fs/ocfs2/inode.h
> index 88924a3..621fc73 100644
> --- a/fs/ocfs2/inode.h
> +++ b/fs/ocfs2/inode.h
> @@ -147,8 +147,6 @@ void ocfs2_refresh_inode(struct inode *inode,
>  int ocfs2_mark_inode_dirty(handle_t *handle,
>  			   struct inode *inode,
>  			   struct buffer_head *bh);
> -int ocfs2_aio_read(struct file *file, struct kiocb *req, struct iocb *iocb);
> -int ocfs2_aio_write(struct file *file, struct kiocb *req, struct iocb *iocb);
>  struct buffer_head *ocfs2_bread(struct inode *inode,
>  				int block, int *err, int reada);
>  
> diff --git a/fs/ocfs2/ocfs2_trace.h b/fs/ocfs2/ocfs2_trace.h
> index 3b481f4..1c5018c 100644
> --- a/fs/ocfs2/ocfs2_trace.h
> +++ b/fs/ocfs2/ocfs2_trace.h
> @@ -1310,13 +1310,13 @@ DEFINE_OCFS2_FILE_OPS(ocfs2_file_release);
>  
>  DEFINE_OCFS2_FILE_OPS(ocfs2_sync_file);
>  
> -DEFINE_OCFS2_FILE_OPS(ocfs2_file_aio_write);
> +DEFINE_OCFS2_FILE_OPS(ocfs2_file_write_iter);
>  
>  DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_write);
>  
>  DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_read);
>  
> -DEFINE_OCFS2_FILE_OPS(ocfs2_file_aio_read);
> +DEFINE_OCFS2_FILE_OPS(ocfs2_file_read_iter);
>  
>  DEFINE_OCFS2_ULL_ULL_ULL_EVENT(ocfs2_truncate_file);
>  
> @@ -1474,7 +1474,7 @@ TRACE_EVENT(ocfs2_prepare_inode_for_write,
>  		  __entry->direct_io, __entry->has_refcount)
>  );
>  
> -DEFINE_OCFS2_INT_EVENT(generic_file_aio_read_ret);
> +DEFINE_OCFS2_INT_EVENT(generic_file_read_iter_ret);
>  
>  /* End of trace events for fs/ocfs2/file.c. */
>  
> -- 
> 1.8.1.1
> 

-- 

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	- Paul Leach, Microsoft

			http://www.jlbec.org/
			jlbec at evilplan.org