[PATCH 377/437] iio: convert to read/write iterators

[Jens Axboe]

Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
 drivers/iio/iio_core.h            |  7 +++----
 drivers/iio/industrialio-buffer.c | 20 +++++++++---------
 drivers/iio/industrialio-core.c   | 34 +++++++++++++++----------------
 drivers/iio/industrialio-event.c  |  3 ++-
 4 files changed, 31 insertions(+), 33 deletions(-)

diff --git a/drivers/iio/iio_core.h b/drivers/iio/iio_core.h
index 1a38b1915e7a..8aac545ec4d0 100644
--- a/drivers/iio/iio_core.h
+++ b/drivers/iio/iio_core.h
@@ -11,6 +11,7 @@
 #define _IIO_CORE_H_
 #include <linux/kernel.h>
 #include <linux/device.h>
+#include <linux/fs.h>
 
 struct iio_buffer;
 struct iio_chan_spec;
@@ -63,10 +64,8 @@ struct poll_table_struct;
 
 __poll_t iio_buffer_poll_wrapper(struct file *filp,
 				 struct poll_table_struct *wait);
-ssize_t iio_buffer_read_wrapper(struct file *filp, char __user *buf,
-				size_t n, loff_t *f_ps);
-ssize_t iio_buffer_write_wrapper(struct file *filp, const char __user *buf,
-				 size_t n, loff_t *f_ps);
+ssize_t iio_buffer_read_wrapper( struct kiocb *iocb, struct iov_iter *to);
+ssize_t iio_buffer_write_wrapper( struct kiocb *iocb, struct iov_iter *from);
 
 int iio_buffers_alloc_sysfs_and_mask(struct iio_dev *indio_dev);
 void iio_buffers_free_sysfs_and_mask(struct iio_dev *indio_dev);
diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index b581a7e80566..38a75f88adf6 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -163,6 +163,7 @@ static ssize_t iio_buffer_read(struct file *filp, char __user *buf,
 
 	return ret;
 }
+FOPS_READ_ITER_HELPER(iio_buffer_read);
 
 static size_t iio_buffer_space_available(struct iio_buffer *buf)
 {
@@ -225,6 +226,7 @@ static ssize_t iio_buffer_write(struct file *filp, const char __user *buf,
 
 	return ret < 0 ? ret : written;
 }
+FOPS_WRITE_ITER_HELPER(iio_buffer_write);
 
 /**
  * iio_buffer_poll() - poll the buffer to find out if it has data
@@ -261,30 +263,28 @@ static __poll_t iio_buffer_poll(struct file *filp,
 	return 0;
 }
 
-ssize_t iio_buffer_read_wrapper(struct file *filp, char __user *buf,
-				size_t n, loff_t *f_ps)
+ssize_t iio_buffer_read_wrapper(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct iio_dev_buffer_pair *ib = filp->private_data;
+	struct iio_dev_buffer_pair *ib = iocb->ki_filp->private_data;
 	struct iio_buffer *rb = ib->buffer;
 
 	/* check if buffer was opened through new API */
 	if (test_bit(IIO_BUSY_BIT_POS, &rb->flags))
 		return -EBUSY;
 
-	return iio_buffer_read(filp, buf, n, f_ps);
+	return vfs_read_iter(iocb, to, iio_buffer_read);
 }
 
-ssize_t iio_buffer_write_wrapper(struct file *filp, const char __user *buf,
-				 size_t n, loff_t *f_ps)
+ssize_t iio_buffer_write_wrapper(struct kiocb *iocb, struct iov_iter *from)
 {
-	struct iio_dev_buffer_pair *ib = filp->private_data;
+	struct iio_dev_buffer_pair *ib = iocb->ki_filp->private_data;
 	struct iio_buffer *rb = ib->buffer;
 
 	/* check if buffer was opened through new API */
 	if (test_bit(IIO_BUSY_BIT_POS, &rb->flags))
 		return -EBUSY;
 
-	return iio_buffer_write(filp, buf, n, f_ps);
+	return vfs_write_iter(iocb, from, iio_buffer_write);
 }
 
 __poll_t iio_buffer_poll_wrapper(struct file *filp,
@@ -1537,8 +1537,8 @@ static int iio_buffer_chrdev_release(struct inode *inode, struct file *filep)
 static const struct file_operations iio_buffer_chrdev_fileops = {
 	.owner = THIS_MODULE,
 	.llseek = noop_llseek,
-	.read = iio_buffer_read,
-	.write = iio_buffer_write,
+	.read_iter = iio_buffer_read_iter,
+	.write_iter = iio_buffer_write_iter,
 	.poll = iio_buffer_poll,
 	.release = iio_buffer_chrdev_release,
 };
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 4302093b92c7..6bf6818e505c 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -369,18 +369,17 @@ static void __exit iio_exit(void)
 }
 
 #if defined(CONFIG_DEBUG_FS)
-static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
-			      size_t count, loff_t *ppos)
+static ssize_t iio_debugfs_read_reg(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct iio_dev *indio_dev = file->private_data;
+	struct iio_dev *indio_dev = iocb->ki_filp->private_data;
 	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
 	unsigned int val = 0;
 	int ret;
 
-	if (*ppos > 0)
-		return simple_read_from_buffer(userbuf, count, ppos,
-					       iio_dev_opaque->read_buf,
-					       iio_dev_opaque->read_buf_len);
+	if (iocb->ki_pos > 0)
+		return simple_copy_to_iter(iio_dev_opaque->read_buf,
+					   &iocb->ki_pos,
+					   iio_dev_opaque->read_buf_len, to);
 
 	ret = indio_dev->info->debugfs_reg_access(indio_dev,
 						  iio_dev_opaque->cached_reg_addr,
@@ -394,22 +393,21 @@ static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
 						sizeof(iio_dev_opaque->read_buf),
 						"0x%X\n", val);
 
-	return simple_read_from_buffer(userbuf, count, ppos,
-				       iio_dev_opaque->read_buf,
-				       iio_dev_opaque->read_buf_len);
+	return simple_copy_to_iter(iio_dev_opaque->read_buf, &iocb->ki_pos,
+				       iio_dev_opaque->read_buf_len, to);
 }
 
-static ssize_t iio_debugfs_write_reg(struct file *file,
-		     const char __user *userbuf, size_t count, loff_t *ppos)
+static ssize_t iio_debugfs_write_reg(struct kiocb *iocb, struct iov_iter *from)
 {
-	struct iio_dev *indio_dev = file->private_data;
+	struct iio_dev *indio_dev = iocb->ki_filp->private_data;
 	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
+	size_t count = iov_iter_count(from);
 	unsigned int reg, val;
 	char buf[80];
 	int ret;
 
 	count = min(count, sizeof(buf) - 1);
-	if (copy_from_user(buf, userbuf, count))
+	if (!copy_from_iter_full(buf, count, from))
 		return -EFAULT;
 
 	buf[count] = 0;
@@ -439,8 +437,8 @@ static ssize_t iio_debugfs_write_reg(struct file *file,
 
 static const struct file_operations iio_debugfs_reg_fops = {
 	.open = simple_open,
-	.read = iio_debugfs_read_reg,
-	.write = iio_debugfs_write_reg,
+	.read_iter = iio_debugfs_read_reg,
+	.write_iter = iio_debugfs_write_reg,
 };
 
 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
@@ -1839,8 +1837,8 @@ static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 static const struct file_operations iio_buffer_fileops = {
 	.owner = THIS_MODULE,
 	.llseek = noop_llseek,
-	.read = iio_buffer_read_outer_addr,
-	.write = iio_buffer_write_outer_addr,
+	.read_iter = iio_buffer_read_outer_addr,
+	.write_iter = iio_buffer_write_outer_addr,
 	.poll = iio_buffer_poll_addr,
 	.unlocked_ioctl = iio_ioctl,
 	.compat_ioctl = compat_ptr_ioctl,
diff --git a/drivers/iio/industrialio-event.c b/drivers/iio/industrialio-event.c
index 910c1f14abd5..b6ce1ac1d1ca 100644
--- a/drivers/iio/industrialio-event.c
+++ b/drivers/iio/industrialio-event.c
@@ -167,6 +167,7 @@ static ssize_t iio_event_chrdev_read(struct file *filep,
 
 	return copied;
 }
+FOPS_READ_ITER_HELPER(iio_event_chrdev_read);
 
 static int iio_event_chrdev_release(struct inode *inode, struct file *filep)
 {
@@ -182,7 +183,7 @@ static int iio_event_chrdev_release(struct inode *inode, struct file *filep)
 }
 
 static const struct file_operations iio_event_chrdev_fileops = {
-	.read =  iio_event_chrdev_read,
+	.read_iter =  iio_event_chrdev_read_iter,
 	.poll =  iio_event_poll,
 	.release = iio_event_chrdev_release,
 	.owner = THIS_MODULE,
-- 
2.43.0