Commit f4c48b44 authored by David Sterba's avatar David Sterba
Browse files

Revert "btrfs: split btrfs_direct_IO to read and write part" 



This reverts commit d8f3e735.

The patch is a cleanup of direct IO port to iomap infrastructure,
which gets reverted.

Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 2166e5ed

fs/btrfs/ctree.h

+0 −3
Original line number Diff line number Diff line
@@ -28,7 +28,6 @@ 
#include <linux/dynamic_debug.h>

#include <linux/refcount.h>

#include <linux/crc32c.h>

#include <linux/iomap.h>

#include "extent-io-tree.h"

#include "extent_io.h"

#include "extent_map.h"
@@ -2935,8 +2934,6 @@ void btrfs_writepage_endio_finish_ordered(struct page *page, u64 start, 
					  u64 end, int uptodate);

extern const struct dentry_operations btrfs_dentry_operations;

ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter);

extern const struct iomap_ops btrfs_dio_iomap_ops;

extern const struct iomap_dio_ops btrfs_dops;



/* ioctl.c */

long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);

fs/btrfs/file.c

+10 −78
Original line number Diff line number Diff line
@@ -1809,61 +1809,21 @@ static noinline ssize_t btrfs_buffered_write(struct kiocb *iocb, 
	return num_written ? num_written : ret;

}



static ssize_t check_direct_IO(struct btrfs_fs_info *fs_info,

                               const struct iov_iter *iter, loff_t offset)

{

        const unsigned int blocksize_mask = fs_info->sectorsize - 1;



        if (offset & blocksize_mask)

                return -EINVAL;



        if (iov_iter_alignment(iter) & blocksize_mask)

                return -EINVAL;



	return 0;

}



static ssize_t btrfs_direct_write(struct kiocb *iocb, struct iov_iter *from)

static ssize_t __btrfs_direct_write(struct kiocb *iocb, struct iov_iter *from)

{

	struct file *file = iocb->ki_filp;

	struct inode *inode = file_inode(file);

	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);

	loff_t pos = iocb->ki_pos;

	ssize_t written = 0;

	loff_t pos;

	ssize_t written;

	ssize_t written_buffered;

	loff_t endbyte;

	int err;

	size_t count = 0;

	bool relock = false;



	if (check_direct_IO(fs_info, from, pos))

		goto buffered;



	count = iov_iter_count(from);

	/*

	 * If the write DIO is beyond the EOF, we need update the isize, but it

	 * is protected by i_mutex. So we can not unlock the i_mutex at this

	 * case.

	 */

	if (pos + count <= inode->i_size) {

		inode_unlock(inode);

		relock = true;

	} else if (iocb->ki_flags & IOCB_NOWAIT) {

		return -EAGAIN;

	}



	down_read(&BTRFS_I(inode)->dio_sem);

	written = iomap_dio_rw(iocb, from, &btrfs_dio_iomap_ops, &btrfs_dops,

			       is_sync_kiocb(iocb));

	up_read(&BTRFS_I(inode)->dio_sem);



	if (relock)

		inode_lock(inode);

	written = btrfs_direct_IO(iocb, from);



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

		return written;



buffered:

	pos = iocb->ki_pos;

	written_buffered = btrfs_buffered_write(iocb, from);

	if (written_buffered < 0) {
@@ -2002,7 +1962,7 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, 
		atomic_inc(&BTRFS_I(inode)->sync_writers);



	if (iocb->ki_flags & IOCB_DIRECT) {

		num_written = btrfs_direct_write(iocb, from);

		num_written = __btrfs_direct_write(iocb, from);

	} else {

		num_written = btrfs_buffered_write(iocb, from);

		if (num_written > 0)
@@ -3516,44 +3476,16 @@ static int btrfs_file_open(struct inode *inode, struct file *filp) 
	return generic_file_open(inode, filp);

}



static int check_direct_read(struct btrfs_fs_info *fs_info,

                               const struct iov_iter *iter, loff_t offset)

static ssize_t btrfs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)

{

	int ret;

	int i, seg;



	ret = check_direct_IO(fs_info, iter, offset);

	if (ret < 0)

		return ret;



	for (seg = 0; seg < iter->nr_segs; seg++)

		for (i = seg + 1; i < iter->nr_segs; i++)

			if (iter->iov[seg].iov_base == iter->iov[i].iov_base)

				return -EINVAL;

	return 0;

}

	ssize_t ret = 0;



static ssize_t btrfs_direct_read(struct kiocb *iocb, struct iov_iter *to)

{

	if (iocb->ki_flags & IOCB_DIRECT) {

		struct inode *inode = file_inode(iocb->ki_filp);

	ssize_t ret;



	if (check_direct_read(btrfs_sb(inode->i_sb), to, iocb->ki_pos))

		return 0;



		inode_lock_shared(inode);

        ret = iomap_dio_rw(iocb, to, &btrfs_dio_iomap_ops, &btrfs_dops,

			   is_sync_kiocb(iocb));

		ret = btrfs_direct_IO(iocb, to);

		inode_unlock_shared(inode);

	return ret;

}



static ssize_t btrfs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)

{

	ssize_t ret = 0;



	if (iocb->ki_flags & IOCB_DIRECT) {

		ret = btrfs_direct_read(iocb, to);

		if (ret < 0)

			return ret;

	}

fs/btrfs/inode.c

+80 −2
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ 
#include <linux/swap.h>

#include <linux/migrate.h>

#include <linux/sched/mm.h>

#include <linux/iomap.h>

#include <asm/unaligned.h>

#include "misc.h"

#include "ctree.h"
@@ -7819,15 +7820,92 @@ static blk_qc_t btrfs_submit_direct(struct inode *inode, struct iomap *iomap, 
	return BLK_QC_T_NONE;

}



const struct iomap_ops btrfs_dio_iomap_ops = {

static ssize_t check_direct_IO(struct btrfs_fs_info *fs_info,

			       const struct iov_iter *iter, loff_t offset)

{

	int seg;

	int i;

	unsigned int blocksize_mask = fs_info->sectorsize - 1;

	ssize_t retval = -EINVAL;



	if (offset & blocksize_mask)

		goto out;



	if (iov_iter_alignment(iter) & blocksize_mask)

		goto out;



	/* If this is a write we don't need to check anymore */

	if (iov_iter_rw(iter) != READ || !iter_is_iovec(iter))

		return 0;

	/*

	 * Check to make sure we don't have duplicate iov_base's in this

	 * iovec, if so return EINVAL, otherwise we'll get csum errors

	 * when reading back.

	 */

	for (seg = 0; seg < iter->nr_segs; seg++) {

		for (i = seg + 1; i < iter->nr_segs; i++) {

			if (iter->iov[seg].iov_base == iter->iov[i].iov_base)

				goto out;

		}

	}

	retval = 0;

out:

	return retval;

}



static const struct iomap_ops btrfs_dio_iomap_ops = {

	.iomap_begin            = btrfs_dio_iomap_begin,

	.iomap_end              = btrfs_dio_iomap_end,

};



const struct iomap_dio_ops btrfs_dops = {

static const struct iomap_dio_ops btrfs_dops = {

	.submit_io		= btrfs_submit_direct,

};



ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)

{

	struct file *file = iocb->ki_filp;

	struct inode *inode = file->f_mapping->host;

	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);

	struct extent_changeset *data_reserved = NULL;

	loff_t offset = iocb->ki_pos;

	size_t count = 0;

	bool relock = false;

	ssize_t ret;



	if (check_direct_IO(fs_info, iter, offset))

		return 0;



	count = iov_iter_count(iter);

	if (iov_iter_rw(iter) == WRITE) {

		/*

		 * If the write DIO is beyond the EOF, we need update

		 * the isize, but it is protected by i_mutex. So we can

		 * not unlock the i_mutex at this case.

		 */

		if (offset + count <= inode->i_size) {

			inode_unlock(inode);

			relock = true;

		} else if (iocb->ki_flags & IOCB_NOWAIT) {

			ret = -EAGAIN;

			goto out;

		}

		down_read(&BTRFS_I(inode)->dio_sem);

	}



	ret = iomap_dio_rw(iocb, iter, &btrfs_dio_iomap_ops, &btrfs_dops,

			is_sync_kiocb(iocb));



	if (iov_iter_rw(iter) == WRITE) {

		up_read(&BTRFS_I(inode)->dio_sem);

	}

out:

	if (relock)

		inode_lock(inode);

	extent_changeset_free(data_reserved);

	return ret;

}



#define BTRFS_FIEMAP_FLAGS	(FIEMAP_FLAG_SYNC)



static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,