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Diffstat (limited to 'net/sunrpc/rpc_pipe.c')
-rw-r--r--net/sunrpc/rpc_pipe.c59
1 files changed, 56 insertions, 3 deletions
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index c59f3ca2b41..7e197168a24 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -76,6 +76,16 @@ rpc_timeout_upcall_queue(struct work_struct *work)
rpc_purge_list(rpci, &free_list, destroy_msg, -ETIMEDOUT);
}
+/**
+ * rpc_queue_upcall
+ * @inode: inode of upcall pipe on which to queue given message
+ * @msg: message to queue
+ *
+ * Call with an @inode created by rpc_mkpipe() to queue an upcall.
+ * A userspace process may then later read the upcall by performing a
+ * read on an open file for this inode. It is up to the caller to
+ * initialize the fields of @msg (other than @msg->list) appropriately.
+ */
int
rpc_queue_upcall(struct inode *inode, struct rpc_pipe_msg *msg)
{
@@ -103,6 +113,7 @@ out:
wake_up(&rpci->waitq);
return res;
}
+EXPORT_SYMBOL(rpc_queue_upcall);
static inline void
rpc_inode_setowner(struct inode *inode, void *private)
@@ -512,8 +523,8 @@ rpc_get_inode(struct super_block *sb, int mode)
/*
* FIXME: This probably has races.
*/
-static void
-rpc_depopulate(struct dentry *parent, int start, int eof)
+static void rpc_depopulate(struct dentry *parent,
+ unsigned long start, unsigned long eof)
{
struct inode *dir = parent->d_inode;
struct list_head *pos, *next;
@@ -663,7 +674,16 @@ rpc_lookup_negative(char *path, struct nameidata *nd)
return dentry;
}
-
+/**
+ * rpc_mkdir - Create a new directory in rpc_pipefs
+ * @path: path from the rpc_pipefs root to the new directory
+ * @rpc_clnt: rpc client to associate with this directory
+ *
+ * This creates a directory at the given @path associated with
+ * @rpc_clnt, which will contain a file named "info" with some basic
+ * information about the client, together with any "pipes" that may
+ * later be created using rpc_mkpipe().
+ */
struct dentry *
rpc_mkdir(char *path, struct rpc_clnt *rpc_client)
{
@@ -699,6 +719,10 @@ err_dput:
goto out;
}
+/**
+ * rpc_rmdir - Remove a directory created with rpc_mkdir()
+ * @dentry: directory to remove
+ */
int
rpc_rmdir(struct dentry *dentry)
{
@@ -717,6 +741,25 @@ rpc_rmdir(struct dentry *dentry)
return error;
}
+/**
+ * rpc_mkpipe - make an rpc_pipefs file for kernel<->userspace communication
+ * @parent: dentry of directory to create new "pipe" in
+ * @name: name of pipe
+ * @private: private data to associate with the pipe, for the caller's use
+ * @ops: operations defining the behavior of the pipe: upcall, downcall,
+ * release_pipe, and destroy_msg.
+ *
+ * Data is made available for userspace to read by calls to
+ * rpc_queue_upcall(). The actual reads will result in calls to
+ * @ops->upcall, which will be called with the file pointer,
+ * message, and userspace buffer to copy to.
+ *
+ * Writes can come at any time, and do not necessarily have to be
+ * responses to upcalls. They will result in calls to @msg->downcall.
+ *
+ * The @private argument passed here will be available to all these methods
+ * from the file pointer, via RPC_I(file->f_dentry->d_inode)->private.
+ */
struct dentry *
rpc_mkpipe(struct dentry *parent, const char *name, void *private, struct rpc_pipe_ops *ops, int flags)
{
@@ -763,7 +806,16 @@ err_dput:
-ENOMEM);
goto out;
}
+EXPORT_SYMBOL(rpc_mkpipe);
+/**
+ * rpc_unlink - remove a pipe
+ * @dentry: dentry for the pipe, as returned from rpc_mkpipe
+ *
+ * After this call, lookups will no longer find the pipe, and any
+ * attempts to read or write using preexisting opens of the pipe will
+ * return -EPIPE.
+ */
int
rpc_unlink(struct dentry *dentry)
{
@@ -785,6 +837,7 @@ rpc_unlink(struct dentry *dentry)
dput(parent);
return error;
}
+EXPORT_SYMBOL(rpc_unlink);
/*
* populate the filesystem