9p: Reorganization of 9p file system code
This patchset moves non-filesystem interfaces of v9fs from fs/9p to net/9p.
It moves the transport, packet marshalling and connection layers to net/9p
leaving only the VFS related files in fs/9p. This work is being done in
preparation for in-kernel 9p servers as well as alternate 9p clients (other
than VFS).
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/net/9p/util.c b/net/9p/util.c
new file mode 100644
index 0000000..22077b7
--- /dev/null
+++ b/net/9p/util.c
@@ -0,0 +1,125 @@
+/*
+ * net/9p/util.c
+ *
+ * This file contains some helper functions
+ *
+ * Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
+ * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to:
+ * Free Software Foundation
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA 02111-1301 USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/parser.h>
+#include <linux/idr.h>
+#include <net/9p/9p.h>
+
+struct p9_idpool {
+ struct semaphore lock;
+ struct idr pool;
+};
+
+struct p9_idpool *p9_idpool_create(void)
+{
+ struct p9_idpool *p;
+
+ p = kmalloc(sizeof(struct p9_idpool), GFP_KERNEL);
+ if (!p)
+ return ERR_PTR(-ENOMEM);
+
+ init_MUTEX(&p->lock);
+ idr_init(&p->pool);
+
+ return p;
+}
+EXPORT_SYMBOL(p9_idpool_create);
+
+void p9_idpool_destroy(struct p9_idpool *p)
+{
+ idr_destroy(&p->pool);
+ kfree(p);
+}
+EXPORT_SYMBOL(p9_idpool_destroy);
+
+/**
+ * p9_idpool_get - allocate numeric id from pool
+ * @p - pool to allocate from
+ *
+ * XXX - This seems to be an awful generic function, should it be in idr.c with
+ * the lock included in struct idr?
+ */
+
+int p9_idpool_get(struct p9_idpool *p)
+{
+ int i = 0;
+ int error;
+
+retry:
+ if (idr_pre_get(&p->pool, GFP_KERNEL) == 0)
+ return 0;
+
+ if (down_interruptible(&p->lock) == -EINTR) {
+ P9_EPRINTK(KERN_WARNING, "Interrupted while locking\n");
+ return -1;
+ }
+
+ /* no need to store exactly p, we just need something non-null */
+ error = idr_get_new(&p->pool, p, &i);
+ up(&p->lock);
+
+ if (error == -EAGAIN)
+ goto retry;
+ else if (error)
+ return -1;
+
+ return i;
+}
+EXPORT_SYMBOL(p9_idpool_get);
+
+/**
+ * p9_idpool_put - release numeric id from pool
+ * @p - pool to allocate from
+ *
+ * XXX - This seems to be an awful generic function, should it be in idr.c with
+ * the lock included in struct idr?
+ */
+
+void p9_idpool_put(int id, struct p9_idpool *p)
+{
+ if (down_interruptible(&p->lock) == -EINTR) {
+ P9_EPRINTK(KERN_WARNING, "Interrupted while locking\n");
+ return;
+ }
+ idr_remove(&p->pool, id);
+ up(&p->lock);
+}
+EXPORT_SYMBOL(p9_idpool_put);
+
+/**
+ * p9_idpool_check - check if the specified id is available
+ * @id - id to check
+ * @p - pool
+ */
+int p9_idpool_check(int id, struct p9_idpool *p)
+{
+ return idr_find(&p->pool, id) != NULL;
+}
+EXPORT_SYMBOL(p9_idpool_check);
