pnfs/blocklayout: move all rpc_pipefs related code into a single file
authorChristoph Hellwig <hch@lst.de>
Thu, 11 Sep 2014 00:37:26 +0000 (17:37 -0700)
committerTrond Myklebust <trond.myklebust@primarydata.com>
Fri, 12 Sep 2014 17:33:50 +0000 (13:33 -0400)
Create a file to house all the rpc_pipefs boilerplate code instead of
sprinkling it over a few files.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
fs/nfs/blocklayout/Makefile
fs/nfs/blocklayout/blocklayout.c
fs/nfs/blocklayout/blocklayout.h
fs/nfs/blocklayout/blocklayoutdev.c [deleted file]
fs/nfs/blocklayout/blocklayoutdm.c [deleted file]
fs/nfs/blocklayout/rpc_pipefs.c [new file with mode: 0644]

index 3fa5ec780a8e30f774c6c974778f1546ef19ef7e..e177026e0119dca8388aa0b9d07aa07c86b08541 100644 (file)
@@ -2,5 +2,5 @@
 # Makefile for the pNFS block layout driver kernel module
 #
 obj-$(CONFIG_PNFS_BLOCK) += blocklayoutdriver.o
-blocklayoutdriver-objs := blocklayout.o blocklayoutdev.o blocklayoutdm.o \
-       extent_tree.o
+
+blocklayoutdriver-y += blocklayout.o extent_tree.o rpc_pipefs.o
index 76ec017a6f0a47bdf10cf632c3f8a0cfd58f0304..65a6b19b17a26895c3d9598c01b9213f8e54f391 100644 (file)
@@ -863,132 +863,6 @@ static struct pnfs_layoutdriver_type blocklayout_type = {
        .pg_write_ops                   = &bl_pg_write_ops,
 };
 
-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;
-
-       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,
-};
-
 static int __init nfs4blocklayout_init(void)
 {
        int ret;
@@ -998,20 +872,14 @@ static int __init nfs4blocklayout_init(void)
        ret = pnfs_register_layoutdriver(&blocklayout_type);
        if (ret)
                goto out;
-
-       ret = rpc_pipefs_notifier_register(&nfs4blocklayout_block);
-       if (ret)
-               goto out_remove;
-       ret = register_pernet_subsys(&nfs4blocklayout_net_ops);
+       ret = bl_init_pipefs();
        if (ret)
-               goto out_notifier;
-out:
-       return ret;
+               goto out_unregister;
+       return 0;
 
-out_notifier:
-       rpc_pipefs_notifier_unregister(&nfs4blocklayout_block);
-out_remove:
+out_unregister:
        pnfs_unregister_layoutdriver(&blocklayout_type);
+out:
        return ret;
 }
 
@@ -1020,8 +888,7 @@ static void __exit nfs4blocklayout_exit(void)
        dprintk("%s: NFSv4 Block Layout Driver Unregistering...\n",
               __func__);
 
-       rpc_pipefs_notifier_unregister(&nfs4blocklayout_block);
-       unregister_pernet_subsys(&nfs4blocklayout_net_ops);
+       bl_cleanup_pipefs();
        pnfs_unregister_layoutdriver(&blocklayout_type);
 }
 
index 00c11eb9d76557af86102d2ad01b3a64a638bc92..c98d98a626642f733cb7b27371362392151fd5e3 100644 (file)
@@ -110,17 +110,6 @@ struct bl_msg_hdr {
 #define BL_DEVICE_REQUEST_PROC         0x1 /* User level process succeeds */
 #define BL_DEVICE_REQUEST_ERR          0x2 /* User level process fails */
 
-/* blocklayoutdev.c */
-ssize_t bl_pipe_downcall(struct file *, const char __user *, size_t);
-void bl_pipe_destroy_msg(struct rpc_pipe_msg *);
-
-struct nfs4_deviceid_node *bl_alloc_deviceid_node(struct nfs_server *server,
-               struct pnfs_device *pdev, gfp_t gfp_mask);
-void bl_free_deviceid_node(struct nfs4_deviceid_node *d);
-
-/* blocklayoutdm.c */
-void bl_dm_remove(struct net *net, dev_t dev);
-
 /* extent_tree.c */
 int ext_tree_insert(struct pnfs_block_layout *bl,
                struct pnfs_block_extent *new);
@@ -133,4 +122,12 @@ bool ext_tree_lookup(struct pnfs_block_layout *bl, sector_t isect,
 int ext_tree_prepare_commit(struct nfs4_layoutcommit_args *arg);
 void ext_tree_mark_committed(struct nfs4_layoutcommit_args *arg, int status);
 
+/* rpc_pipefs.c */
+struct nfs4_deviceid_node *bl_alloc_deviceid_node(struct nfs_server *server,
+               struct pnfs_device *pdev, gfp_t gfp_mask);
+void bl_free_deviceid_node(struct nfs4_deviceid_node *d);
+
+int __init bl_init_pipefs(void);
+void __exit bl_cleanup_pipefs(void);
+
 #endif /* FS_NFS_NFS4BLOCKLAYOUT_H */
diff --git a/fs/nfs/blocklayout/blocklayoutdev.c b/fs/nfs/blocklayout/blocklayoutdev.c
deleted file mode 100644 (file)
index 2b54e29..0000000
+++ /dev/null
@@ -1,172 +0,0 @@
-/*
- *  linux/fs/nfs/blocklayout/blocklayoutdev.c
- *
- *  Device operations for the pnfs nfs4 file layout driver.
- *
- *  Copyright (c) 2006 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/buffer_head.h> /* __bread */
-
-#include <linux/genhd.h>
-#include <linux/blkdev.h>
-#include <linux/hash.h>
-
-#include "blocklayout.h"
-
-#define NFSDBG_FACILITY         NFSDBG_PNFS_LD
-
-ssize_t bl_pipe_downcall(struct file *filp, const char __user *src,
-                        size_t mlen)
-{
-       struct nfs_net *nn = net_generic(filp->f_dentry->d_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;
-}
-
-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);
-}
-
-/*
- * Decodes pnfs_block_deviceaddr4 which is XDR encoded in dev->dev_addr_buf.
- */
-struct nfs4_deviceid_node *
-bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *dev,
-               gfp_t gfp_mask)
-{
-       struct pnfs_block_dev *rv;
-       struct block_device *bd;
-       struct bl_pipe_msg bl_pipe_msg;
-       struct rpc_pipe_msg *msg = &bl_pipe_msg.msg;
-       struct bl_msg_hdr bl_msg = {
-               .type = BL_DEVICE_MOUNT,
-               .totallen = dev->mincount,
-       };
-       uint8_t *dataptr;
-       DECLARE_WAITQUEUE(wq, current);
-       int offset, len, i, rc;
-       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;
-
-       dprintk("%s CREATING PIPEFS MESSAGE\n", __func__);
-       dprintk("%s: deviceid: %s, mincount: %d\n", __func__, dev->dev_id.data,
-               dev->mincount);
-
-       bl_pipe_msg.bl_wq = &nn->bl_wq;
-       memset(msg, 0, sizeof(*msg));
-       msg->data = kzalloc(sizeof(bl_msg) + dev->mincount, gfp_mask);
-       if (!msg->data)
-               goto out;
-
-       memcpy(msg->data, &bl_msg, sizeof(bl_msg));
-       dataptr = (uint8_t *) msg->data;
-       len = dev->mincount;
-       offset = sizeof(bl_msg);
-       for (i = 0; len > 0; i++) {
-               memcpy(&dataptr[offset], page_address(dev->pages[i]),
-                               len < PAGE_CACHE_SIZE ? len : PAGE_CACHE_SIZE);
-               len -= PAGE_CACHE_SIZE;
-               offset += PAGE_CACHE_SIZE;
-       }
-       msg->len = sizeof(bl_msg) + dev->mincount;
-
-       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;
-       }
-
-       set_current_state(TASK_UNINTERRUPTIBLE);
-       schedule();
-       __set_current_state(TASK_RUNNING);
-       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;
-       }
-
-       bd = blkdev_get_by_dev(MKDEV(reply->major, reply->minor),
-                              FMODE_READ, NULL);
-       if (IS_ERR(bd)) {
-               printk(KERN_WARNING "%s failed to open device %d:%d (%ld)\n",
-                       __func__, reply->major, reply->minor,
-                       PTR_ERR(bd));
-               goto out;
-       }
-
-       rv = kzalloc(sizeof(*rv), gfp_mask);
-       if (!rv)
-               goto out;
-
-       nfs4_init_deviceid_node(&rv->d_node, server, &dev->dev_id);
-       rv->d_bdev = bd;
-
-       dprintk("%s Created device %s with bd_block_size %u\n",
-               __func__,
-               bd->bd_disk->disk_name,
-               bd->bd_block_size);
-
-       kfree(msg->data);
-       return &rv->d_node;
-
-out:
-       kfree(msg->data);
-       return NULL;
-}
-
-void
-bl_free_deviceid_node(struct nfs4_deviceid_node *d)
-{
-       struct pnfs_block_dev *dev =
-               container_of(d, struct pnfs_block_dev, d_node);
-       struct net *net = d->nfs_client->cl_net;
-
-       blkdev_put(dev->d_bdev, FMODE_READ);
-       bl_dm_remove(net, dev->d_bdev->bd_dev);
-
-       kfree(dev);
-}
diff --git a/fs/nfs/blocklayout/blocklayoutdm.c b/fs/nfs/blocklayout/blocklayoutdm.c
deleted file mode 100644 (file)
index abc2e9e..0000000
+++ /dev/null
@@ -1,84 +0,0 @@
-/*
- *  linux/fs/nfs/blocklayout/blocklayoutdm.c
- *
- *  Module for the NFSv4.1 pNFS block layout driver.
- *
- *  Copyright (c) 2007 The Regents of the University of Michigan.
- *  All rights reserved.
- *
- *  Fred Isaman <iisaman@umich.edu>
- *  Andy Adamson <andros@citi.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/genhd.h> /* gendisk - used in a dprintk*/
-#include <linux/sched.h>
-#include <linux/hash.h>
-
-#include "blocklayout.h"
-
-#define NFSDBG_FACILITY         NFSDBG_PNFS_LD
-
-void bl_dm_remove(struct net *net, dev_t dev)
-{
-       struct bl_pipe_msg bl_pipe_msg;
-       struct rpc_pipe_msg *msg = &bl_pipe_msg.msg;
-       struct bl_dev_msg bl_umount_request;
-       struct bl_msg_hdr bl_msg = {
-               .type = BL_DEVICE_UMOUNT,
-               .totallen = sizeof(bl_umount_request),
-       };
-       uint8_t *dataptr;
-       DECLARE_WAITQUEUE(wq, current);
-       struct nfs_net *nn = net_generic(net, nfs_net_id);
-
-       dprintk("Entering %s\n", __func__);
-
-       bl_pipe_msg.bl_wq = &nn->bl_wq;
-       memset(msg, 0, sizeof(*msg));
-       msg->len = sizeof(bl_msg) + bl_msg.totallen;
-       msg->data = kzalloc(msg->len, GFP_NOFS);
-       if (!msg->data)
-               goto out;
-
-       memset(&bl_umount_request, 0, sizeof(bl_umount_request));
-       bl_umount_request.major = MAJOR(dev);
-       bl_umount_request.minor = MINOR(dev);
-
-       memcpy(msg->data, &bl_msg, sizeof(bl_msg));
-       dataptr = (uint8_t *) msg->data;
-       memcpy(&dataptr[sizeof(bl_msg)], &bl_umount_request, sizeof(bl_umount_request));
-
-       add_wait_queue(&nn->bl_wq, &wq);
-       if (rpc_queue_upcall(nn->bl_device_pipe, msg) < 0) {
-               remove_wait_queue(&nn->bl_wq, &wq);
-               goto out;
-       }
-
-       set_current_state(TASK_UNINTERRUPTIBLE);
-       schedule();
-       __set_current_state(TASK_RUNNING);
-       remove_wait_queue(&nn->bl_wq, &wq);
-
-out:
-       kfree(msg->data);
-}
diff --git a/fs/nfs/blocklayout/rpc_pipefs.c b/fs/nfs/blocklayout/rpc_pipefs.c
new file mode 100644 (file)
index 0000000..bfb0486
--- /dev/null
@@ -0,0 +1,362 @@
+/*
+ *  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 bl_dm_remove(struct net *net, dev_t dev)
+{
+       struct bl_pipe_msg bl_pipe_msg;
+       struct rpc_pipe_msg *msg = &bl_pipe_msg.msg;
+       struct bl_dev_msg bl_umount_request;
+       struct bl_msg_hdr bl_msg = {
+               .type = BL_DEVICE_UMOUNT,
+               .totallen = sizeof(bl_umount_request),
+       };
+       uint8_t *dataptr;
+       DECLARE_WAITQUEUE(wq, current);
+       struct nfs_net *nn = net_generic(net, nfs_net_id);
+
+       dprintk("Entering %s\n", __func__);
+
+       bl_pipe_msg.bl_wq = &nn->bl_wq;
+       memset(msg, 0, sizeof(*msg));
+       msg->len = sizeof(bl_msg) + bl_msg.totallen;
+       msg->data = kzalloc(msg->len, GFP_NOFS);
+       if (!msg->data)
+               goto out;
+
+       memset(&bl_umount_request, 0, sizeof(bl_umount_request));
+       bl_umount_request.major = MAJOR(dev);
+       bl_umount_request.minor = MINOR(dev);
+
+       memcpy(msg->data, &bl_msg, sizeof(bl_msg));
+       dataptr = (uint8_t *) msg->data;
+       memcpy(&dataptr[sizeof(bl_msg)], &bl_umount_request, sizeof(bl_umount_request));
+
+       add_wait_queue(&nn->bl_wq, &wq);
+       if (rpc_queue_upcall(nn->bl_device_pipe, msg) < 0) {
+               remove_wait_queue(&nn->bl_wq, &wq);
+               goto out;
+       }
+
+       set_current_state(TASK_UNINTERRUPTIBLE);
+       schedule();
+       __set_current_state(TASK_RUNNING);
+       remove_wait_queue(&nn->bl_wq, &wq);
+
+out:
+       kfree(msg->data);
+}
+
+/*
+ * Decodes pnfs_block_deviceaddr4 which is XDR encoded in dev->dev_addr_buf.
+ */
+struct nfs4_deviceid_node *
+bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *dev,
+               gfp_t gfp_mask)
+{
+       struct pnfs_block_dev *rv;
+       struct block_device *bd;
+       struct bl_pipe_msg bl_pipe_msg;
+       struct rpc_pipe_msg *msg = &bl_pipe_msg.msg;
+       struct bl_msg_hdr bl_msg = {
+               .type = BL_DEVICE_MOUNT,
+               .totallen = dev->mincount,
+       };
+       uint8_t *dataptr;
+       DECLARE_WAITQUEUE(wq, current);
+       int offset, len, i, rc;
+       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;
+
+       dprintk("%s CREATING PIPEFS MESSAGE\n", __func__);
+       dprintk("%s: deviceid: %s, mincount: %d\n", __func__, dev->dev_id.data,
+               dev->mincount);
+
+       bl_pipe_msg.bl_wq = &nn->bl_wq;
+       memset(msg, 0, sizeof(*msg));
+       msg->data = kzalloc(sizeof(bl_msg) + dev->mincount, gfp_mask);
+       if (!msg->data)
+               goto out;
+
+       memcpy(msg->data, &bl_msg, sizeof(bl_msg));
+       dataptr = (uint8_t *) msg->data;
+       len = dev->mincount;
+       offset = sizeof(bl_msg);
+       for (i = 0; len > 0; i++) {
+               memcpy(&dataptr[offset], page_address(dev->pages[i]),
+                               len < PAGE_CACHE_SIZE ? len : PAGE_CACHE_SIZE);
+               len -= PAGE_CACHE_SIZE;
+               offset += PAGE_CACHE_SIZE;
+       }
+       msg->len = sizeof(bl_msg) + dev->mincount;
+
+       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;
+       }
+
+       set_current_state(TASK_UNINTERRUPTIBLE);
+       schedule();
+       __set_current_state(TASK_RUNNING);
+       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;
+       }
+
+       bd = blkdev_get_by_dev(MKDEV(reply->major, reply->minor),
+                              FMODE_READ, NULL);
+       if (IS_ERR(bd)) {
+               printk(KERN_WARNING "%s failed to open device %d:%d (%ld)\n",
+                       __func__, reply->major, reply->minor,
+                       PTR_ERR(bd));
+               goto out;
+       }
+
+       rv = kzalloc(sizeof(*rv), gfp_mask);
+       if (!rv)
+               goto out;
+
+       nfs4_init_deviceid_node(&rv->d_node, server, &dev->dev_id);
+       rv->d_bdev = bd;
+
+       dprintk("%s Created device %s with bd_block_size %u\n",
+               __func__,
+               bd->bd_disk->disk_name,
+               bd->bd_block_size);
+
+       kfree(msg->data);
+       return &rv->d_node;
+
+out:
+       kfree(msg->data);
+       return NULL;
+}
+
+void
+bl_free_deviceid_node(struct nfs4_deviceid_node *d)
+{
+       struct pnfs_block_dev *dev =
+               container_of(d, struct pnfs_block_dev, d_node);
+       struct net *net = d->nfs_client->cl_net;
+
+       blkdev_put(dev->d_bdev, FMODE_READ);
+       bl_dm_remove(net, dev->d_bdev->bd_dev);
+
+       kfree(dev);
+}
+
+static ssize_t bl_pipe_downcall(struct file *filp, const char __user *src,
+                        size_t mlen)
+{
+       struct nfs_net *nn = net_generic(filp->f_dentry->d_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;
+
+       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);
+}