blkdev_write_iter: expand generic_file_checks() call in there
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/block_dev.c b/fs/block_dev.c
index bcd7f97..897ee05 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1595,18 +1595,21 @@
ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
struct file *file = iocb->ki_filp;
+ struct inode *bd_inode = file->f_mapping->host;
+ loff_t size = i_size_read(bd_inode);
struct blk_plug plug;
ssize_t ret;
- size_t count = iov_iter_count(from);
- ret = generic_write_checks(file, &iocb->ki_pos, &count, 1);
- if (ret)
- return ret;
+ if (bdev_read_only(I_BDEV(bd_inode)))
+ return -EPERM;
- if (count == 0)
+ if (!iov_iter_count(from))
return 0;
- iov_iter_truncate(from, count);
+ if (iocb->ki_pos >= size)
+ return -ENOSPC;
+
+ iov_iter_truncate(from, size - iocb->ki_pos);
blk_start_plug(&plug);
ret = __generic_file_write_iter(iocb, from);