Commit 87fa0f3e authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Linus Torvalds
Browse files

mm/filemap: rename generic_file_buffered_read to filemap_read 

Rename generic_file_buffered_read to match the naming of filemap_fault,
also update the written parameter to a more descriptive name and improve
the kerneldoc comment.

Link: https://lkml.kernel.org/r/20210122160140.223228-18-willy@infradead.org


Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatarKent Overstreet <kent.overstreet@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent aa1ec2f6

fs/btrfs/file.c

+1 −1
Original line number Diff line number Diff line
@@ -3634,7 +3634,7 @@ static ssize_t btrfs_file_read_iter(struct kiocb *iocb, struct iov_iter *to) 
			return ret;

	}



	return generic_file_buffered_read(iocb, to, ret);

	return filemap_read(iocb, to, ret);

}



const struct file_operations btrfs_file_operations = {

include/linux/fs.h

+2 −2
Original line number Diff line number Diff line
@@ -3080,8 +3080,8 @@ extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *); 
extern int generic_write_check_limits(struct file *file, loff_t pos,

		loff_t *count);

extern int generic_file_rw_checks(struct file *file_in, struct file *file_out);

extern ssize_t generic_file_buffered_read(struct kiocb *iocb,

		struct iov_iter *to, ssize_t already_read);

ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *to,

		ssize_t already_read);

extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);

extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *);

extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *);

mm/filemap.c

+16 −19
Original line number Diff line number Diff line
@@ -2394,23 +2394,20 @@ static int filemap_get_pages(struct kiocb *iocb, struct iov_iter *iter, 
}



/**

 * generic_file_buffered_read - generic file read routine

 * @iocb:	the iocb to read

 * @iter:	data destination

 * @written:	already copied

 * filemap_read - Read data from the page cache.

 * @iocb: The iocb to read.

 * @iter: Destination for the data.

 * @already_read: Number of bytes already read by the caller.

 *

 * This is a generic file read routine, and uses the

 * mapping->a_ops->readpage() function for the actual low-level stuff.

 * Copies data from the page cache.  If the data is not currently present,

 * uses the readahead and readpage address_space operations to fetch it.

 *

 * This is really ugly. But the goto's actually try to clarify some

 * of the logic when it comes to error handling etc.

 *

 * Return:

 * * total number of bytes copied, including those the were already @written

 * * negative error code if nothing was copied

 * Return: Total number of bytes copied, including those already read by

 * the caller.  If an error happens before any bytes are copied, returns

 * a negative error number.

 */

ssize_t generic_file_buffered_read(struct kiocb *iocb,

		struct iov_iter *iter, ssize_t written)

ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *iter,

		ssize_t already_read)

{

	struct file *filp = iocb->ki_filp;

	struct file_ra_state *ra = &filp->f_ra;
@@ -2437,7 +2434,7 @@ ssize_t generic_file_buffered_read(struct kiocb *iocb, 
		 * can no longer safely return -EIOCBQUEUED. Hence mark

		 * an async read NOWAIT at that point.

		 */

		if ((iocb->ki_flags & IOCB_WAITQ) && written)

		if ((iocb->ki_flags & IOCB_WAITQ) && already_read)

			iocb->ki_flags |= IOCB_NOWAIT;



		error = filemap_get_pages(iocb, iter, &pvec);
@@ -2497,7 +2494,7 @@ ssize_t generic_file_buffered_read(struct kiocb *iocb, 


			copied = copy_page_to_iter(page, offset, bytes, iter);



			written += copied;

			already_read += copied;

			iocb->ki_pos += copied;

			ra->prev_pos = iocb->ki_pos;
@@ -2514,9 +2511,9 @@ ssize_t generic_file_buffered_read(struct kiocb *iocb, 


	file_accessed(filp);



	return written ? written : error;

	return already_read ? already_read : error;

}

EXPORT_SYMBOL_GPL(generic_file_buffered_read);

EXPORT_SYMBOL_GPL(filemap_read);



/**

 * generic_file_read_iter - generic filesystem read routine
@@ -2591,7 +2588,7 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) 
			goto out;

	}



	retval = generic_file_buffered_read(iocb, iter, retval);

	retval = filemap_read(iocb, iter, retval);

out:

	return retval;

}