/* * 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 bl_cleanup_pipefs(void) { rpc_pipefs_notifier_unregister(&nfs4blocklayout_block); unregister_pernet_subsys(&nfs4blocklayout_net_ops); }