replace ->follow_link() with new method that could stay in RCU mode
new method: ->get_link(); replacement of ->follow_link(). The differences
are:
* inode and dentry are passed separately
* might be called both in RCU and non-RCU mode;
the former is indicated by passing it a NULL dentry.
* when called that way it isn't allowed to block
and should return ERR_PTR(-ECHILD) if it needs to be called
in non-RCU mode.
It's a flagday change - the old method is gone, all in-tree instances
converted. Conversion isn't hard; said that, so far very few instances
do not immediately bail out when called in RCU mode. That'll change
in the next commits.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c
index f6e8354..63861c1 100644
--- a/fs/proc/namespaces.c
+++ b/fs/proc/namespaces.c
@@ -30,14 +30,17 @@
&mntns_operations,
};
-static const char *proc_ns_follow_link(struct dentry *dentry, void **cookie)
+static const char *proc_ns_get_link(struct dentry *dentry,
+ struct inode *inode, void **cookie)
{
- struct inode *inode = d_inode(dentry);
const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns_ops;
struct task_struct *task;
struct path ns_path;
void *error = ERR_PTR(-EACCES);
+ if (!dentry)
+ return ERR_PTR(-ECHILD);
+
task = get_proc_task(inode);
if (!task)
return error;
@@ -74,7 +77,7 @@
static const struct inode_operations proc_ns_link_inode_operations = {
.readlink = proc_ns_readlink,
- .follow_link = proc_ns_follow_link,
+ .get_link = proc_ns_get_link,
.setattr = proc_setattr,
};