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/configfs/symlink.c b/fs/configfs/symlink.c
index ec5c832..b91c01e 100644
--- a/fs/configfs/symlink.c
+++ b/fs/configfs/symlink.c
@@ -279,11 +279,16 @@
}
-static const char *configfs_follow_link(struct dentry *dentry, void **cookie)
+static const char *configfs_get_link(struct dentry *dentry,
+ struct inode *inode, void **cookie)
{
- unsigned long page = get_zeroed_page(GFP_KERNEL);
+ unsigned long page;
int error;
+ if (!dentry)
+ return ERR_PTR(-ECHILD);
+
+ page = get_zeroed_page(GFP_KERNEL);
if (!page)
return ERR_PTR(-ENOMEM);
@@ -297,7 +302,7 @@
}
const struct inode_operations configfs_symlink_inode_operations = {
- .follow_link = configfs_follow_link,
+ .get_link = configfs_get_link,
.readlink = generic_readlink,
.put_link = free_page_put_link,
.setattr = configfs_setattr,