Received-SPF: pass (google.com: domain of linux-kernel+bounces-140769-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3;
From: Jens Axboe <axboe@kernel.dk>
To: linux-kernel@vger.kernel.org
Cc: Jens Axboe <axboe@kernel.dk>
Subject: [PATCH 012/437] char/adi: convert to read/write iterators
Date: Thu, 11 Apr 2024 09:12:32 -0600
Message-ID: <20240411153126.16201-13-axboe@kernel.dk>
In-Reply-To: <20240411153126.16201-1-axboe@kernel.dk>
References: <20240411153126.16201-1-axboe@kernel.dk>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 drivers/char/adi.c | 26 ++++++++++++--------------
 1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/drivers/char/adi.c b/drivers/char/adi.c
index 751d7cc0da1b..941188be2385 100644
--- a/drivers/char/adi.c
+++ b/drivers/char/adi.c
@@ -51,10 +51,10 @@ static int read_mcd_tag(unsigned long addr)
 		return ver;
 }
 
-static ssize_t adi_read(struct file *file, char __user *buf,
-			size_t count, loff_t *offp)
+static ssize_t adi_read(struct kiocb *iocb, struct iov_iter *to)
 {
 	size_t ver_buf_sz, bytes_read = 0;
+	size_t count = iov_iter_count(to);
 	int ver_buf_idx = 0;
 	loff_t offset;
 	u8 *ver_buf;
@@ -65,7 +65,7 @@ static ssize_t adi_read(struct file *file, char __user *buf,
 	if (!ver_buf)
 		return -ENOMEM;
 
-	offset = (*offp) * adi_blksize();
+	offset = iocb->ki_pos * adi_blksize();
 
 	while (bytes_read < count) {
 		ret = read_mcd_tag(offset);
@@ -77,8 +77,7 @@ static ssize_t adi_read(struct file *file, char __user *buf,
 		offset += adi_blksize();
 
 		if (ver_buf_idx >= ver_buf_sz) {
-			if (copy_to_user(buf + bytes_read, ver_buf,
-					 ver_buf_sz)) {
+			if (!copy_to_iter_full(ver_buf, ver_buf_sz, to)) {
 				ret = -EFAULT;
 				goto out;
 			}
@@ -91,7 +90,7 @@ static ssize_t adi_read(struct file *file, char __user *buf,
 		}
 	}
 
-	(*offp) += bytes_read;
+	iocb->ki_pos += bytes_read;
 	ret = bytes_read;
 out:
 	kfree(ver_buf);
@@ -128,10 +127,10 @@ static int set_mcd_tag(unsigned long addr, u8 ver)
 		return ver;
 }
 
-static ssize_t adi_write(struct file *file, const char __user *buf,
-			 size_t count, loff_t *offp)
+static ssize_t adi_write(struct kiocb *iocb, struct iov_iter *from)
 {
 	size_t ver_buf_sz, bytes_written = 0;
+	size_t count = iov_iter_count(from);
 	loff_t offset;
 	u8 *ver_buf;
 	ssize_t ret;
@@ -145,11 +144,10 @@ static ssize_t adi_write(struct file *file, const char __user *buf,
 	if (!ver_buf)
 		return -ENOMEM;
 
-	offset = (*offp) * adi_blksize();
+	offset = iocb->ki_pos * adi_blksize();
 
 	do {
-		if (copy_from_user(ver_buf, &buf[bytes_written],
-				   ver_buf_sz)) {
+		if (!copy_from_iter_full(ver_buf, ver_buf_sz, from)) {
 			ret = -EFAULT;
 			goto out;
 		}
@@ -166,7 +164,7 @@ static ssize_t adi_write(struct file *file, const char __user *buf,
 		ver_buf_sz = min(count - bytes_written, (size_t)MAX_BUF_SZ);
 	} while (bytes_written < count);
 
-	(*offp) += bytes_written;
+	iocb->ki_pos += bytes_written;
 	ret = bytes_written;
 out:
 	__asm__ __volatile__("membar #Sync");
@@ -207,8 +205,8 @@ static const struct file_operations adi_fops = {
 	.owner		= THIS_MODULE,
 	.llseek		= adi_llseek,
 	.open		= adi_open,
-	.read		= adi_read,
-	.write		= adi_write,
+	.read_iter	= adi_read,
+	.write_iter	= adi_write,
 };
 
 static struct miscdevice adi_miscdev = {
-- 
2.43.0