[Xen-devel] [PATCHv1 2/2] xen/xenfs: replace xenbus and privcmd with symlinks

[David Vrabel <david.vrabel@xxxxxxxxxx>]

/proc/xen/xenbus does not work correctly.  A read blocked waiting for
a xenbus message will deadlock a write to the same file handle due to
the requirement for atomic file position updates on regular files.

/proc/xen/xenbus and /proc/xen/privcmd are supposed to be identical to
the character devices /dev/xen/xenbus and /dev/xen/privcmd so replace
the files with symlinks.

Signed-off-by: David Vrabel <david.vrabel@xxxxxxxxxx>
---
 drivers/xen/xenfs/super.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/xen/xenfs/super.c b/drivers/xen/xenfs/super.c
index 8559a71..09c239e 100644
--- a/drivers/xen/xenfs/super.c
+++ b/drivers/xen/xenfs/super.c
@@ -45,16 +45,16 @@ static const struct file_operations capabilities_file_ops = 
{
 static int xenfs_fill_super(struct super_block *sb, void *data, int silent)
 {
        static struct tree_descr xenfs_files[] = {
-               [2] = { "xenbus", &xen_xenbus_fops, S_IRUSR|S_IWUSR },
+               [2] = { "xenbus", NULL, S_IFLNK | S_IRWXUGO, "/dev/xen/xenbus" 
},
                { "capabilities", &capabilities_file_ops, S_IRUGO },
-               { "privcmd", &xen_privcmd_fops, S_IRUSR|S_IWUSR },
+               { "privcmd", NULL, S_IFLNK | S_IRWXUGO, "/dev/xen/privcmd" },
                {""},
        };
 
        static struct tree_descr xenfs_init_files[] = {
-               [2] = { "xenbus", &xen_xenbus_fops, S_IRUSR|S_IWUSR },
+               [2] = { "xenbus", NULL, S_IFLNK | S_IRWXUGO, "/dev/xen/xenbus" 
},
                { "capabilities", &capabilities_file_ops, S_IRUGO },
-               { "privcmd", &xen_privcmd_fops, S_IRUSR|S_IWUSR },
+               { "privcmd", NULL, S_IFLNK | S_IRWXUGO, "/dev/xen/privcmd" },
                { "xsd_kva", &xsd_kva_file_ops, S_IRUSR|S_IWUSR},
                { "xsd_port", &xsd_port_file_ops, S_IRUSR|S_IWUSR},
 #ifdef CONFIG_XEN_SYMS
-- 
2.1.4


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