9p: fix device file handling

In v9fs_get_inode(), for block, as well as char devices (in theory),
the function init_special_inode() is called to set up callback functions
for file ops. this function uses the file mode's value to determine whether
to use block or char dev functions. In v9fs_inode_from_fid(), the function
p9mode2unixmode() is used, but for all devices it initially returns S_IFBLK,
then uses v9fs_get_inode() to initialise a new inode, then finally uses
v9fs_stat2inode(), which would determine whether the inode is a block or
character device. However, at that point init_special_inode() had already
decided to use the block device functions, so even if the inode's mode is
turned to a character device, the block functions are still used to operate
on them. The attached patch simply calls init_special_inode() again for devices
after parsing device node data in v9fs_stat2inode() so that the proper functions
are used.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index e96d84a..8314d3f 100644 (file)
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -864,6 +864,7 @@ v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
                                stat->extension);
                };
                inode->i_rdev = MKDEV(major, minor);
+               init_special_inode(inode, inode->i_mode, inode->i_rdev);
        } else
                inode->i_rdev = 0;