switch /dev/kmsg to ->write_iter()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 7 insertions, 13 deletions

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 1ce770687ea8..7a6e69441f75 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -519,14 +519,13 @@ struct devkmsg_user {
         char buf[8192];
 };
 
-static ssize_t devkmsg_writev(struct kiocb *iocb, const struct iovec *iv,
-                              unsigned long count, loff_t pos)
+static ssize_t devkmsg_write(struct kiocb *iocb, struct iov_iter *from)
 {
         char *buf, *line;
         int i;
         int level = default_message_loglevel;
         int facility = 1;       /* LOG_USER */
-        size_t len = iov_length(iv, count);
+        size_t len = iocb->ki_nbytes;
         ssize_t ret = len;
 
         if (len > LOG_LINE_MAX)
@@ -535,13 +534,10 @@ static ssize_t devkmsg_writev(struct kiocb *iocb, const struct iovec *iv,
         if (buf == NULL)
                 return -ENOMEM;
 
-        line = buf;
-        for (i = 0; i < count; i++) {
-                if (copy_from_user(line, iv[i].iov_base, iv[i].iov_len)) {
-                        ret = -EFAULT;
-                        goto out;
-                }
-                line += iv[i].iov_len;
+        buf[len] = '\0';
+        if (copy_from_iter(buf, len, from) != len) {
+                kfree(buf);
+                return -EFAULT;
         }
 
         /*
@@ -567,10 +563,8 @@ static ssize_t devkmsg_writev(struct kiocb *iocb, const struct iovec *iv,
                         line = endp;
                 }
         }
-        line[len] = '\0';
 
         printk_emit(facility, level, NULL, 0, "%s", line);
-out:
         kfree(buf);
         return ret;
 }
@@ -802,7 +796,7 @@ static int devkmsg_release(struct inode *inode, struct file *file)
 const struct file_operations kmsg_fops = {
         .open = devkmsg_open,
         .read = devkmsg_read,
-        .aio_write = devkmsg_writev,
+        .write_iter = devkmsg_write,
         .llseek = devkmsg_llseek,
         .poll = devkmsg_poll,
         .release = devkmsg_release,