summaryrefslogtreecommitdiff
path: root/fs/nfs/blocklayout/rpc_pipefs.c
diff options
context:
space:
mode:
authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/nfs/blocklayout/rpc_pipefs.c
Initial import
Diffstat (limited to 'fs/nfs/blocklayout/rpc_pipefs.c')
-rw-r--r--fs/nfs/blocklayout/rpc_pipefs.c288
1 files changed, 288 insertions, 0 deletions
diff --git a/fs/nfs/blocklayout/rpc_pipefs.c b/fs/nfs/blocklayout/rpc_pipefs.c
new file mode 100644
index 000000000..dbe5839cd
--- /dev/null
+++ b/fs/nfs/blocklayout/rpc_pipefs.c
@@ -0,0 +1,288 @@
+/*
+ * Copyright (c) 2006,2007 The Regents of the University of Michigan.
+ * All rights reserved.
+ *
+ * Andy Adamson <andros@citi.umich.edu>
+ * Fred Isaman <iisaman@umich.edu>
+ *
+ * permission is granted to use, copy, create derivative works and
+ * redistribute this software and such derivative works for any purpose,
+ * so long as the name of the university of michigan is not used in
+ * any advertising or publicity pertaining to the use or distribution
+ * of this software without specific, written prior authorization. if
+ * the above copyright notice or any other identification of the
+ * university of michigan is included in any copy of any portion of
+ * this software, then the disclaimer below must also be included.
+ *
+ * this software is provided as is, without representation from the
+ * university of michigan as to its fitness for any purpose, and without
+ * warranty by the university of michigan of any kind, either express
+ * or implied, including without limitation the implied warranties of
+ * merchantability and fitness for a particular purpose. the regents
+ * of the university of michigan shall not be liable for any damages,
+ * including special, indirect, incidental, or consequential damages,
+ * with respect to any claim arising out or in connection with the use
+ * of the software, even if it has been or is hereafter advised of the
+ * possibility of such damages.
+ */
+
+#include <linux/module.h>
+#include <linux/genhd.h>
+#include <linux/blkdev.h>
+
+#include "blocklayout.h"
+
+#define NFSDBG_FACILITY NFSDBG_PNFS_LD
+
+static void
+nfs4_encode_simple(__be32 *p, struct pnfs_block_volume *b)
+{
+ int i;
+
+ *p++ = cpu_to_be32(1);
+ *p++ = cpu_to_be32(b->type);
+ *p++ = cpu_to_be32(b->simple.nr_sigs);
+ for (i = 0; i < b->simple.nr_sigs; i++) {
+ p = xdr_encode_hyper(p, b->simple.sigs[i].offset);
+ p = xdr_encode_opaque(p, b->simple.sigs[i].sig,
+ b->simple.sigs[i].sig_len);
+ }
+}
+
+dev_t
+bl_resolve_deviceid(struct nfs_server *server, struct pnfs_block_volume *b,
+ gfp_t gfp_mask)
+{
+ struct net *net = server->nfs_client->cl_net;
+ struct nfs_net *nn = net_generic(net, nfs_net_id);
+ struct bl_dev_msg *reply = &nn->bl_mount_reply;
+ struct bl_pipe_msg bl_pipe_msg;
+ struct rpc_pipe_msg *msg = &bl_pipe_msg.msg;
+ struct bl_msg_hdr *bl_msg;
+ DECLARE_WAITQUEUE(wq, current);
+ dev_t dev = 0;
+ int rc;
+
+ dprintk("%s CREATING PIPEFS MESSAGE\n", __func__);
+
+ mutex_lock(&nn->bl_mutex);
+ bl_pipe_msg.bl_wq = &nn->bl_wq;
+
+ b->simple.len += 4; /* single volume */
+ if (b->simple.len > PAGE_SIZE)
+ goto out_unlock;
+
+ memset(msg, 0, sizeof(*msg));
+ msg->len = sizeof(*bl_msg) + b->simple.len;
+ msg->data = kzalloc(msg->len, gfp_mask);
+ if (!msg->data)
+ goto out_free_data;
+
+ bl_msg = msg->data;
+ bl_msg->type = BL_DEVICE_MOUNT,
+ bl_msg->totallen = b->simple.len;
+ nfs4_encode_simple(msg->data + sizeof(*bl_msg), b);
+
+ dprintk("%s CALLING USERSPACE DAEMON\n", __func__);
+ add_wait_queue(&nn->bl_wq, &wq);
+ rc = rpc_queue_upcall(nn->bl_device_pipe, msg);
+ if (rc < 0) {
+ remove_wait_queue(&nn->bl_wq, &wq);
+ goto out_free_data;
+ }
+
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule();
+ remove_wait_queue(&nn->bl_wq, &wq);
+
+ if (reply->status != BL_DEVICE_REQUEST_PROC) {
+ printk(KERN_WARNING "%s failed to decode device: %d\n",
+ __func__, reply->status);
+ goto out_free_data;
+ }
+
+ dev = MKDEV(reply->major, reply->minor);
+out_free_data:
+ kfree(msg->data);
+out_unlock:
+ mutex_unlock(&nn->bl_mutex);
+ return dev;
+}
+
+static ssize_t bl_pipe_downcall(struct file *filp, const char __user *src,
+ size_t mlen)
+{
+ struct nfs_net *nn = net_generic(file_inode(filp)->i_sb->s_fs_info,
+ nfs_net_id);
+
+ if (mlen != sizeof (struct bl_dev_msg))
+ return -EINVAL;
+
+ if (copy_from_user(&nn->bl_mount_reply, src, mlen) != 0)
+ return -EFAULT;
+
+ wake_up(&nn->bl_wq);
+
+ return mlen;
+}
+
+static void bl_pipe_destroy_msg(struct rpc_pipe_msg *msg)
+{
+ struct bl_pipe_msg *bl_pipe_msg =
+ container_of(msg, struct bl_pipe_msg, msg);
+
+ if (msg->errno >= 0)
+ return;
+ wake_up(bl_pipe_msg->bl_wq);
+}
+
+static const struct rpc_pipe_ops bl_upcall_ops = {
+ .upcall = rpc_pipe_generic_upcall,
+ .downcall = bl_pipe_downcall,
+ .destroy_msg = bl_pipe_destroy_msg,
+};
+
+static struct dentry *nfs4blocklayout_register_sb(struct super_block *sb,
+ struct rpc_pipe *pipe)
+{
+ struct dentry *dir, *dentry;
+
+ dir = rpc_d_lookup_sb(sb, NFS_PIPE_DIRNAME);
+ if (dir == NULL)
+ return ERR_PTR(-ENOENT);
+ dentry = rpc_mkpipe_dentry(dir, "blocklayout", NULL, pipe);
+ dput(dir);
+ return dentry;
+}
+
+static void nfs4blocklayout_unregister_sb(struct super_block *sb,
+ struct rpc_pipe *pipe)
+{
+ if (pipe->dentry)
+ rpc_unlink(pipe->dentry);
+}
+
+static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
+ void *ptr)
+{
+ struct super_block *sb = ptr;
+ struct net *net = sb->s_fs_info;
+ struct nfs_net *nn = net_generic(net, nfs_net_id);
+ struct dentry *dentry;
+ int ret = 0;
+
+ if (!try_module_get(THIS_MODULE))
+ return 0;
+
+ if (nn->bl_device_pipe == NULL) {
+ module_put(THIS_MODULE);
+ return 0;
+ }
+
+ switch (event) {
+ case RPC_PIPEFS_MOUNT:
+ dentry = nfs4blocklayout_register_sb(sb, nn->bl_device_pipe);
+ if (IS_ERR(dentry)) {
+ ret = PTR_ERR(dentry);
+ break;
+ }
+ nn->bl_device_pipe->dentry = dentry;
+ break;
+ case RPC_PIPEFS_UMOUNT:
+ if (nn->bl_device_pipe->dentry)
+ nfs4blocklayout_unregister_sb(sb, nn->bl_device_pipe);
+ break;
+ default:
+ ret = -ENOTSUPP;
+ break;
+ }
+ module_put(THIS_MODULE);
+ return ret;
+}
+
+static struct notifier_block nfs4blocklayout_block = {
+ .notifier_call = rpc_pipefs_event,
+};
+
+static struct dentry *nfs4blocklayout_register_net(struct net *net,
+ struct rpc_pipe *pipe)
+{
+ struct super_block *pipefs_sb;
+ struct dentry *dentry;
+
+ pipefs_sb = rpc_get_sb_net(net);
+ if (!pipefs_sb)
+ return NULL;
+ dentry = nfs4blocklayout_register_sb(pipefs_sb, pipe);
+ rpc_put_sb_net(net);
+ return dentry;
+}
+
+static void nfs4blocklayout_unregister_net(struct net *net,
+ struct rpc_pipe *pipe)
+{
+ struct super_block *pipefs_sb;
+
+ pipefs_sb = rpc_get_sb_net(net);
+ if (pipefs_sb) {
+ nfs4blocklayout_unregister_sb(pipefs_sb, pipe);
+ rpc_put_sb_net(net);
+ }
+}
+
+static int nfs4blocklayout_net_init(struct net *net)
+{
+ struct nfs_net *nn = net_generic(net, nfs_net_id);
+ struct dentry *dentry;
+
+ mutex_init(&nn->bl_mutex);
+ init_waitqueue_head(&nn->bl_wq);
+ nn->bl_device_pipe = rpc_mkpipe_data(&bl_upcall_ops, 0);
+ if (IS_ERR(nn->bl_device_pipe))
+ return PTR_ERR(nn->bl_device_pipe);
+ dentry = nfs4blocklayout_register_net(net, nn->bl_device_pipe);
+ if (IS_ERR(dentry)) {
+ rpc_destroy_pipe_data(nn->bl_device_pipe);
+ return PTR_ERR(dentry);
+ }
+ nn->bl_device_pipe->dentry = dentry;
+ return 0;
+}
+
+static void nfs4blocklayout_net_exit(struct net *net)
+{
+ struct nfs_net *nn = net_generic(net, nfs_net_id);
+
+ nfs4blocklayout_unregister_net(net, nn->bl_device_pipe);
+ rpc_destroy_pipe_data(nn->bl_device_pipe);
+ nn->bl_device_pipe = NULL;
+}
+
+static struct pernet_operations nfs4blocklayout_net_ops = {
+ .init = nfs4blocklayout_net_init,
+ .exit = nfs4blocklayout_net_exit,
+};
+
+int __init bl_init_pipefs(void)
+{
+ int ret;
+
+ ret = rpc_pipefs_notifier_register(&nfs4blocklayout_block);
+ if (ret)
+ goto out;
+ ret = register_pernet_subsys(&nfs4blocklayout_net_ops);
+ if (ret)
+ goto out_unregister_notifier;
+ return 0;
+
+out_unregister_notifier:
+ rpc_pipefs_notifier_unregister(&nfs4blocklayout_block);
+out:
+ return ret;
+}
+
+void __exit bl_cleanup_pipefs(void)
+{
+ rpc_pipefs_notifier_unregister(&nfs4blocklayout_block);
+ unregister_pernet_subsys(&nfs4blocklayout_net_ops);
+}