[PATCH 023/437] char/lp: convert to read/write iterators

From: Jens Axboe
Date: Thu Apr 11 2024 - 11:46:14 EST


Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
drivers/char/lp.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/char/lp.c b/drivers/char/lp.c
index 2f171d14b9b5..3967115f6c75 100644
--- a/drivers/char/lp.c
+++ b/drivers/char/lp.c
@@ -298,10 +298,11 @@ static int lp_wait_ready(int minor, int nonblock)
return error;
}

-static ssize_t lp_write(struct file *file, const char __user *buf,
- size_t count, loff_t *ppos)
+static ssize_t lp_write(struct kiocb *iocb, struct iov_iter *from)
{
+ struct file *file = iocb->ki_filp;
unsigned int minor = iminor(file_inode(file));
+ size_t count = iov_iter_count(from);
struct parport *port = lp_table[minor].dev->port;
char *kbuf = lp_table[minor].lp_buffer;
ssize_t retv = 0;
@@ -324,7 +325,7 @@ static ssize_t lp_write(struct file *file, const char __user *buf,
if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
return -EINTR;

- if (copy_from_user(kbuf, buf, copy_size)) {
+ if (!copy_from_iter_full(kbuf, copy_size, from)) {
retv = -EFAULT;
goto out_unlock;
}
@@ -347,7 +348,6 @@ static ssize_t lp_write(struct file *file, const char __user *buf,
if (written > 0) {
copy_size -= written;
count -= written;
- buf += written;
retv += written;
}

@@ -391,7 +391,7 @@ static ssize_t lp_write(struct file *file, const char __user *buf,
if (copy_size > LP_BUFFER_SIZE)
copy_size = LP_BUFFER_SIZE;

- if (copy_from_user(kbuf, buf, copy_size)) {
+ if (!copy_from_iter_full(kbuf, copy_size, from)) {
if (retv == 0)
retv = -EFAULT;
break;
@@ -416,9 +416,10 @@ static ssize_t lp_write(struct file *file, const char __user *buf,
#ifdef CONFIG_PARPORT_1284

/* Status readback conforming to ieee1284 */
-static ssize_t lp_read(struct file *file, char __user *buf,
- size_t count, loff_t *ppos)
+static ssize_t lp_read(struct kiocb *iocb, struct iov_iter *to)
{
+ struct file *file = iocb->ki_filp;
+ size_t count = iov_iter_count(to);
DEFINE_WAIT(wait);
unsigned int minor=iminor(file_inode(file));
struct parport *port = lp_table[minor].dev->port;
@@ -485,7 +486,7 @@ static ssize_t lp_read(struct file *file, char __user *buf,
out:
lp_release_parport(&lp_table[minor]);

- if (retval > 0 && copy_to_user(buf, kbuf, retval))
+ if (retval > 0 && !copy_to_iter_full(kbuf, retval, to))
retval = -EFAULT;

mutex_unlock(&lp_table[minor].port_mutex);
@@ -785,7 +786,7 @@ static long lp_compat_ioctl(struct file *file, unsigned int cmd,

static const struct file_operations lp_fops = {
.owner = THIS_MODULE,
- .write = lp_write,
+ .write_iter = lp_write,
.unlocked_ioctl = lp_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = lp_compat_ioctl,
@@ -793,7 +794,7 @@ static const struct file_operations lp_fops = {
.open = lp_open,
.release = lp_release,
#ifdef CONFIG_PARPORT_1284
- .read = lp_read,
+ .read_iter = lp_read,
#endif
.llseek = noop_llseek,
};
--
2.43.0