[Devel] [PATCH rh7 23/30] dax: dax_iomap_rw(): switch to iov_iter

[Kirill Tkhai]

Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
---
 fs/dax.c            |   13 +++++--------
 fs/ext4/file.c      |   12 ++++++++++--
 fs/xfs/xfs_file.c   |   10 ++++++++--
 include/linux/dax.h |    4 ++--
 4 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/fs/dax.c b/fs/dax.c
index 57d5b0a86a30..f22e3b32b6cc 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -1357,25 +1357,22 @@ dax_iomap_actor_write(struct inode *inode, loff_t pos, loff_t length, void *data
  * and evicting any page cache pages in the region under I/O.
  */
 ssize_t
-dax_iomap_rw(int rw, struct kiocb *iocb, const struct iovec *iov,
-                unsigned long nr_segs, loff_t pos,
+dax_iomap_rw(int rw, struct kiocb *iocb, struct iov_iter *iter,
+                loff_t pos,
                 size_t count, const struct iomap_ops *ops)
 {
 	struct address_space *mapping = iocb->ki_filp->f_mapping;
 	struct inode *inode = mapping->host;
 	loff_t ret = 0, done = 0;
 	unsigned flags = 0;
-	struct iov_iter iter;
-
-	iov_iter_init(&iter, iov, nr_segs, count, 0);
 
 	if (rw & WRITE)
 		flags |= IOMAP_WRITE;
 
 
-	while (iov_iter_count(&iter)) {
-		ret = iomap_apply(inode, pos, iov_iter_count(&iter), flags, ops,
-				&iter,
+	while (iov_iter_count(iter)) {
+		ret = iomap_apply(inode, pos, iov_iter_count(iter), flags, ops,
+				iter,
 				(rw & WRITE) ?
 				  dax_iomap_actor_write : dax_iomap_actor_read);
 		if (ret <= 0)
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 3adbb7b72c5a..2808aadd4033 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -220,6 +220,7 @@ ext4_file_dax_write(
 	struct inode *inode = file_inode(iocb->ki_filp);
 	ssize_t			ret;
 	size_t			size = iov_length(iovp, nr_segs);
+	struct iov_iter iter;
 
 	inode_lock(inode);
 	ret = ext4_write_checks(iocb, iovp, nr_segs, &pos);
@@ -232,7 +233,9 @@ ext4_file_dax_write(
 	if (ret)
 		goto out;
 
-	ret = dax_iomap_rw(WRITE, iocb, iovp, nr_segs, pos,
+	iov_iter_init(&iter, iovp, nr_segs, size, 0);
+
+	ret = dax_iomap_rw(WRITE, iocb, &iter, pos,
 					size, &ext4_iomap_ops);
 out:
 	inode_unlock(inode);
@@ -516,6 +519,8 @@ ext4_file_dax_read(
 	size_t			size = iov_length(iovp, nr_segs);
 	ssize_t			ret = 0;
 	struct inode *inode = file_inode(iocb->ki_filp);
+	struct iov_iter iter;
+
 	if (!size)
 		return 0; /* skip atime */
 
@@ -529,7 +534,10 @@ ext4_file_dax_read(
 		/* Fallback to buffered IO in case we cannot support DAX */
 		return generic_file_aio_read(iocb, iovp, nr_segs, pos);
 	}
-	ret = dax_iomap_rw(READ, iocb, iovp, nr_segs, pos,
+
+	iov_iter_init(&iter, iovp, nr_segs, size, 0);
+
+	ret = dax_iomap_rw(READ, iocb, &iter, pos,
 					size, &ext4_iomap_ops);
 	inode_unlock(inode);
 
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 67a632f2c00f..378e8e826474 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -318,6 +318,7 @@ xfs_file_dax_read(
 	struct xfs_inode	*ip = XFS_I(iocb->ki_filp->f_mapping->host);
 	size_t			size = 0;
 	ssize_t			ret = 0;
+	struct iov_iter iter;
 
 	size = iov_length(iovp, nr_segs);
 
@@ -326,8 +327,10 @@ xfs_file_dax_read(
 	if (!size)
 		return 0; /* skip atime */
 
+	iov_iter_init(&iter, iovp, nr_segs, size, 0);
+
 	xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
-	ret = dax_iomap_rw(READ, iocb, iovp, nr_segs, pos,
+	ret = dax_iomap_rw(READ, iocb, &iter, pos,
 			   size, &xfs_iomap_ops);
 	xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
 
@@ -776,6 +779,7 @@ xfs_file_dax_write(
 	size_t			count = ocount;
 	int			iolock = XFS_IOLOCK_EXCL;
 	ssize_t			ret, error = 0;
+	struct iov_iter iter;
 
 	xfs_rw_ilock(ip, iolock);
 	ret = xfs_file_aio_write_checks(file, &pos, &count, &iolock);
@@ -787,7 +791,9 @@ xfs_file_dax_write(
 
 	trace_xfs_file_dax_write(ip, count, pos);
 
-	ret = dax_iomap_rw(WRITE, iocb, iovp, nr_segs, pos,
+	iov_iter_init(&iter, iovp, nr_segs, count, 0);
+
+	ret = dax_iomap_rw(WRITE, iocb, &iter, pos,
 			   count, &xfs_iomap_ops);
 	if (ret > 0 && iocb->ki_pos > i_size_read(inode)) {
 		i_size_write(inode, iocb->ki_pos);
diff --git a/include/linux/dax.h b/include/linux/dax.h
index 0195fd3db7c9..7e3a23236ec4 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -144,8 +144,8 @@ int dax_memcpy_toiovecend(struct dax_device *dax_dev, pgoff_t pgoff,
 		const struct iovec *iov, void *addr, int offset, int len);
 void dax_flush(struct dax_device *dax_dev, void *addr, size_t size);
 
-ssize_t dax_iomap_rw(int rw, struct kiocb *iocb, const struct iovec *iov,
-		unsigned long nr_segs, loff_t pos,
+ssize_t dax_iomap_rw(int rw, struct kiocb *iocb, struct iov_iter *iter,
+		loff_t pos,
 		size_t count, const struct iomap_ops *ops);
 int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
 		pfn_t *pfnp, int *errp, const struct iomap_ops *ops);