/* * linux/fs/nfs/inode.c * * Copyright (C) 1992 Rick Sladkey * * nfs inode and superblock handling functions * * Modularised by Alan Cox , while hacking some * experimental NFS changes. Modularisation taken straight from SYS5 fs. * * Change to nfs_read_super() to permit NFS mounts to multi-homed hosts. * J.S.Peatfield@damtp.cam.ac.uk * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define CONFIG_NFS_SNAPSHOT 1 #define NFSDBG_FACILITY NFSDBG_VFS #define NFS_PARANOIA 1 static struct inode * __nfs_fhget(struct super_block *, struct nfs_fattr *); void nfs_zap_caches(struct inode *); static void nfs_invalidate_inode(struct inode *); static void nfs_read_inode(struct inode *); static void nfs_put_inode(struct inode *); static void nfs_delete_inode(struct inode *); static int nfs_notify_change(struct dentry *, struct iattr *); static void nfs_put_super(struct super_block *); static void nfs_umount_begin(struct super_block *); static int nfs_statfs(struct super_block *, struct statfs *, int); static struct super_operations nfs_sops = { nfs_read_inode, /* read inode */ NULL, /* write inode */ nfs_put_inode, /* put inode */ nfs_delete_inode, /* delete inode */ nfs_notify_change, /* notify change */ nfs_put_super, /* put superblock */ NULL, /* write superblock */ nfs_statfs, /* stat filesystem */ NULL, /* no remount */ NULL, /* no clear inode */ nfs_umount_begin /* umount attempt begin */ }; struct rpc_stat nfs_rpcstat = { &nfs_program }; /* * The "read_inode" function doesn't actually do anything: * the real data is filled in later in nfs_fhget. Here we * just mark the cache times invalid, and zero out i_mode * (the latter makes "nfs_refresh_inode" do the right thing * wrt pipe inodes) */ static void nfs_read_inode(struct inode * inode) { inode->i_blksize = inode->i_sb->s_blocksize; inode->i_mode = 0; inode->i_rdev = 0; inode->i_op = NULL; NFS_FILEID(inode) = 0; NFS_FSID(inode) = 0; NFS_CACHEINV(inode); NFS_ATTRTIMEO(inode) = NFS_MINATTRTIMEO(inode); } static void nfs_put_inode(struct inode * inode) { dprintk("NFS: put_inode(%x/%ld)\n", inode->i_dev, inode->i_ino); /* * We want to get rid of unused inodes ... */ if (inode->i_count == 1) inode->i_nlink = 0; } static void nfs_delete_inode(struct inode * inode) { int failed; dprintk("NFS: delete_inode(%x/%ld)\n", inode->i_dev, inode->i_ino); if (S_ISDIR(inode->i_mode)) { nfs_free_dircache(inode); } else { /* * Flush out any pending write requests ... */ if (NFS_WRITEBACK(inode) != NULL) { unsigned long timeout = jiffies + 5*HZ; #ifdef NFS_DEBUG_VERBOSE printk("nfs_delete_inode: inode %ld has pending RPC requests\n", inode->i_ino); #endif nfs_inval(inode); while (NFS_WRITEBACK(inode) != NULL && time_before(jiffies, timeout)) { current->state = TASK_INTERRUPTIBLE; schedule_timeout(HZ/10); } current->state = TASK_RUNNING; if (NFS_WRITEBACK(inode) != NULL) printk("NFS: Arghhh, stuck RPC requests!\n"); } } failed = nfs_check_failed_request(inode); if (failed) printk("NFS: inode %ld had %d failed requests\n", inode->i_ino, failed); clear_inode(inode); } void nfs_put_super(struct super_block *sb) { struct nfs_server *server = &sb->u.nfs_sb.s_server; struct rpc_clnt *rpc; if ((rpc = server->client) != NULL) rpc_shutdown_client(rpc); if (!(server->flags & NFS_MOUNT_NONLM)) lockd_down(); /* release rpc.lockd */ rpciod_down(); /* release rpciod */ kfree(server->hostname); MOD_DEC_USE_COUNT; } void nfs_umount_begin(struct super_block *sb) { struct nfs_server *server = &sb->u.nfs_sb.s_server; struct rpc_clnt *rpc; /* -EIO all pending I/O */ if ((rpc = server->client) != NULL) rpc_killall_tasks(rpc); } /* * Compute and set NFS server blocksize */ static unsigned int nfs_block_size(unsigned int bsize, unsigned char *nrbitsp) { if (bsize < 1024) bsize = NFS_DEF_FILE_IO_BUFFER_SIZE; else if (bsize >= NFS_MAX_FILE_IO_BUFFER_SIZE) bsize = NFS_MAX_FILE_IO_BUFFER_SIZE; /* make sure blocksize is a power of two */ if ((bsize & (bsize - 1)) || nrbitsp) { unsigned int nrbits; for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--) ; bsize = 1 << nrbits; if (nrbitsp) *nrbitsp = nrbits; if (bsize < NFS_DEF_FILE_IO_BUFFER_SIZE) bsize = NFS_DEF_FILE_IO_BUFFER_SIZE; } return bsize; } extern struct nfs_fh *nfs_fh_alloc(void); extern void nfs_fh_free(struct nfs_fh *p); /* * The way this works is that the mount process passes a structure * in the data argument which contains the server's IP address * and the root file handle obtained from the server's mount * daemon. We stash these away in the private superblock fields. */ struct super_block * nfs_read_super(struct super_block *sb, void *raw_data, int silent) { struct nfs_mount_data *data = (struct nfs_mount_data *) raw_data; struct nfs_server *server; struct rpc_xprt *xprt; struct rpc_clnt *clnt; struct nfs_fh *root_fh; struct inode *root_inode; unsigned int authflavor; int tcp; struct sockaddr_in srvaddr; struct rpc_timeout timeparms; struct nfs_fattr fattr; MOD_INC_USE_COUNT; if (!data) goto out_miss_args; if (data->version != NFS_MOUNT_VERSION) { printk("nfs warning: mount version %s than kernel\n", data->version < NFS_MOUNT_VERSION ? "older" : "newer"); if (data->version < 2) data->namlen = 0; if (data->version < 3) data->bsize = 0; } /* We now require that the mount process passes the remote address */ memcpy(&srvaddr, &data->addr, sizeof(srvaddr)); if (srvaddr.sin_addr.s_addr == INADDR_ANY) goto out_no_remote; lock_super(sb); sb->s_flags |= MS_ODD_RENAME; /* This should go away */ sb->s_magic = NFS_SUPER_MAGIC; sb->s_op = &nfs_sops; sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits); sb->u.nfs_sb.s_root = data->root; server = &sb->u.nfs_sb.s_server; server->rsize = nfs_block_size(data->rsize, NULL); server->wsize = nfs_block_size(data->wsize, NULL); server->flags = data->flags; if (data->flags & NFS_MOUNT_NOAC) { data->acregmin = data->acregmax = 0; data->acdirmin = data->acdirmax = 0; } server->acregmin = data->acregmin*HZ; server->acregmax = data->acregmax*HZ; server->acdirmin = data->acdirmin*HZ; server->acdirmax = data->acdirmax*HZ; server->hostname = kmalloc(strlen(data->hostname) + 1, GFP_KERNEL); if (!server->hostname) goto out_unlock; strcpy(server->hostname, data->hostname); /* Which protocol do we use? */ tcp = (data->flags & NFS_MOUNT_TCP); /* Initialize timeout values */ timeparms.to_initval = data->timeo * HZ / 10; timeparms.to_retries = data->retrans; timeparms.to_maxval = tcp? RPC_MAX_TCP_TIMEOUT : RPC_MAX_UDP_TIMEOUT; timeparms.to_exponential = 1; /* Now create transport and client */ xprt = xprt_create_proto(tcp? IPPROTO_TCP : IPPROTO_UDP, &srvaddr, &timeparms); if (xprt == NULL) goto out_no_xprt; /* Choose authentication flavor */ authflavor = RPC_AUTH_UNIX; if (data->flags & NFS_MOUNT_SECURE) authflavor = RPC_AUTH_DES; else if (data->flags & NFS_MOUNT_KERBEROS) authflavor = RPC_AUTH_KRB; clnt = rpc_create_client(xprt, server->hostname, &nfs_program, NFS_VERSION, authflavor); if (clnt == NULL) goto out_no_client; clnt->cl_intr = (data->flags & NFS_MOUNT_INTR)? 1 : 0; clnt->cl_softrtry = (data->flags & NFS_MOUNT_SOFT)? 1 : 0; clnt->cl_chatty = 1; server->client = clnt; /* Fire up rpciod if not yet running */ if (rpciod_up() != 0) goto out_no_iod; /* * Keep the super block locked while we try to get * the root fh attributes. */ root_fh = nfs_fh_alloc(); if (!root_fh) goto out_no_fh; *root_fh = data->root; if (nfs_proc_getattr(server, root_fh, &fattr) != 0) goto out_no_fattr; root_inode = __nfs_fhget(sb, &fattr); if (!root_inode) goto out_no_root; sb->s_root = d_alloc_root(root_inode); if (!sb->s_root) goto out_no_root; sb->s_root->d_op = &nfs_dentry_operations; sb->s_root->d_fsdata = root_fh; /* We're airborne */ unlock_super(sb); /* Check whether to start the lockd process */ if (!(server->flags & NFS_MOUNT_NONLM)) lockd_up(); return sb; /* Yargs. It didn't work out. */ out_no_root: printk("nfs_read_super: get root inode failed\n"); iput(root_inode); goto out_free_fh; out_no_fattr: printk("nfs_read_super: get root fattr failed\n"); out_free_fh: nfs_fh_free(root_fh); out_no_fh: rpciod_down(); goto out_shutdown; out_no_iod: printk(KERN_WARNING "NFS: couldn't start rpciod!\n"); out_shutdown: rpc_shutdown_client(server->client); goto out_free_host; out_no_client: printk(KERN_WARNING "NFS: cannot create RPC client.\n"); xprt_destroy(xprt); goto out_free_host; out_no_xprt: printk(KERN_WARNING "NFS: cannot create RPC transport.\n"); out_free_host: kfree(server->hostname); out_unlock: unlock_super(sb); goto out_fail; out_no_remote: printk("NFS: mount program didn't pass remote address!\n"); goto out_fail; out_miss_args: printk("nfs_read_super: missing data argument\n"); out_fail: sb->s_dev = 0; MOD_DEC_USE_COUNT; return NULL; } static int nfs_statfs(struct super_block *sb, struct statfs *buf, int bufsiz) { int error; struct nfs_fsinfo res; struct statfs tmp; error = nfs_proc_statfs(&sb->u.nfs_sb.s_server, &sb->u.nfs_sb.s_root, &res); if (error) { printk("nfs_statfs: statfs error = %d\n", -error); res.bsize = res.blocks = res.bfree = res.bavail = 0; } tmp.f_type = NFS_SUPER_MAGIC; tmp.f_bsize = res.bsize; tmp.f_blocks = res.blocks; tmp.f_bfree = res.bfree; tmp.f_bavail = res.bavail; tmp.f_files = 0; tmp.f_ffree = 0; tmp.f_namelen = NAME_MAX; return copy_to_user(buf, &tmp, bufsiz) ? -EFAULT : 0; } /* * Free all unused dentries in an inode's alias list. * * Subtle note: we have to be very careful not to cause * any IO operations with the stale dentries, as this * could cause file corruption. But since the dentry * count is 0 and all pending IO for a dentry has been * flushed when the count went to 0, we're safe here. * Also returns the number of unhashed dentries */ static int nfs_free_dentries(struct inode *inode) { struct list_head *tmp, *head = &inode->i_dentry; int unhashed; restart: tmp = head; unhashed = 0; while ((tmp = tmp->next) != head) { struct dentry *dentry = list_entry(tmp, struct dentry, d_alias); dprintk("nfs_free_dentries: found %s/%s, d_count=%d, hashed=%d\n", dentry->d_parent->d_name.name, dentry->d_name.name, dentry->d_count, !list_empty(&dentry->d_hash)); if (!list_empty(&dentry->d_subdirs)) shrink_dcache_parent(dentry); if (!dentry->d_count) { dget(dentry); d_drop(dentry); dput(dentry); goto restart; } if (list_empty(&dentry->d_hash)) unhashed++; } return unhashed; } /* * Invalidate the local caches */ void nfs_zap_caches(struct inode *inode) { NFS_ATTRTIMEO(inode) = NFS_MINATTRTIMEO(inode); NFS_CACHEINV(inode); invalidate_inode_pages(inode); if (S_ISDIR(inode->i_mode)) nfs_flush_dircache(inode); } /* * Invalidate, but do not unhash, the inode */ static void nfs_invalidate_inode(struct inode *inode) { umode_t save_mode = inode->i_mode; make_bad_inode(inode); inode->i_mode = save_mode; nfs_inval(inode); nfs_zap_caches(inode); } /* * Fill in inode information from the fattr. */ static void nfs_fill_inode(struct inode *inode, struct nfs_fattr *fattr) { /* * Check whether the mode has been set, as we only want to * do this once. (We don't allow inodes to change types.) */ if (inode->i_mode == 0) { NFS_FILEID(inode) = fattr->fileid; NFS_FSID(inode) = fattr->fsid; inode->i_mode = fattr->mode; if (S_ISREG(inode->i_mode)) inode->i_op = &nfs_file_inode_operations; else if (S_ISDIR(inode->i_mode)) inode->i_op = &nfs_dir_inode_operations; else if (S_ISLNK(inode->i_mode)) inode->i_op = &nfs_symlink_inode_operations; else init_special_inode(inode, inode->i_mode, fattr->rdev); /* * Preset the size and mtime, as there's no need * to invalidate the caches. */ inode->i_size = fattr->size; inode->i_mtime = fattr->mtime.seconds; NFS_OLDMTIME(inode) = fattr->mtime.seconds; } nfs_refresh_inode(inode, fattr); } /* * In NFSv3 we can have 64bit inode numbers. In order to support * this, and re-exported directories (also seen in NFSv2) * we are forced to allow 2 different inodes to have the same * i_ino. */ static int nfs_find_actor(struct inode *inode, unsigned long ino, void *opaque) { struct nfs_fattr *fattr = (struct nfs_fattr *)opaque; if (NFS_FSID(inode) != fattr->fsid) return 0; if (NFS_FILEID(inode) != fattr->fileid) return 0; return 1; } static int nfs_inode_is_stale(struct inode *inode, struct nfs_fattr *fattr) { int unhashed; int is_stale = 0; if (inode->i_mode && (fattr->mode & S_IFMT) != (inode->i_mode & S_IFMT)) is_stale = 1; if (is_bad_inode(inode)) is_stale = 1; /* * If the inode seems stale, free up cached dentries. */ unhashed = nfs_free_dentries(inode); /* Assume we're holding an i_count * * NB: sockets sometimes have volatile file handles * don't invalidate their inodes even if all dentries are * unhashed. */ if (unhashed && inode->i_count == unhashed + 1 && !S_ISSOCK(inode->i_mode) && !S_ISFIFO(inode->i_mode)) is_stale = 1; return is_stale; } /* * This is our own version of iget that looks up inodes by file handle * instead of inode number. We use this technique instead of using * the vfs read_inode function because there is no way to pass the * file handle or current attributes into the read_inode function. * * We provide a special check for NetApp .snapshot directories to avoid * inode aliasing problems. All snapshot inodes are anonymous (unhashed). */ struct inode * nfs_fhget(struct dentry *dentry, struct nfs_fh *fhandle, struct nfs_fattr *fattr) { struct super_block *sb = dentry->d_sb; dprintk("NFS: nfs_fhget(%s/%s fileid=%d)\n", dentry->d_parent->d_name.name, dentry->d_name.name, fattr->fileid); /* Install the file handle in the dentry */ *((struct nfs_fh *) dentry->d_fsdata) = *fhandle; #ifdef CONFIG_NFS_SNAPSHOT /* * Check for NetApp snapshot dentries, and get an * unhashed inode to avoid aliasing problems. */ if ((dentry->d_parent->d_inode->u.nfs_i.flags & NFS_IS_SNAPSHOT) || (dentry->d_name.len == 9 && memcmp(dentry->d_name.name, ".snapshot", 9) == 0)) { struct inode *inode = get_empty_inode(); if (!inode) goto out; inode->i_sb = sb; inode->i_dev = sb->s_dev; inode->i_flags = 0; inode->i_ino = fattr->fileid; nfs_read_inode(inode); nfs_fill_inode(inode, fattr); inode->u.nfs_i.flags |= NFS_IS_SNAPSHOT; dprintk("NFS: nfs_fhget(snapshot ino=%ld)\n", inode->i_ino); out: return inode; } #endif return __nfs_fhget(sb, fattr); } /* * Look up the inode by super block and fattr->fileid. * * Note carefully the special handling of busy inodes (i_count > 1). * With the kernel 2.1.xx dcache all inodes except hard links must * have i_count == 1 after iget(). Otherwise, it indicates that the * server has reused a fileid (i_ino) and we have a stale inode. */ static struct inode * __nfs_fhget(struct super_block *sb, struct nfs_fattr *fattr) { struct inode *inode = NULL; unsigned long ino; if (!fattr->nlink) { printk("NFS: Buggy server - nlink == 0!\n"); goto out_no_inode; } ino = fattr->fileid; while((inode = iget4(sb, ino, nfs_find_actor, fattr)) != NULL) { /* * Check for busy inodes, and attempt to get rid of any * unused local references. If successful, we release the * inode and try again. * * Note that the busy test uses the values in the fattr, * as the inode may have become a different object. * (We can probably handle modes changes here, too.) */ if (!nfs_inode_is_stale(inode,fattr)) break; dprintk("__nfs_fhget: inode %ld still busy, i_count=%d\n", inode->i_ino, inode->i_count); nfs_zap_caches(inode); remove_inode_hash(inode); iput(inode); } if (!inode) goto out_no_inode; nfs_fill_inode(inode, fattr); dprintk("NFS: __nfs_fhget(%x/%ld ct=%d)\n", inode->i_dev, inode->i_ino, inode->i_count); out: return inode; out_no_inode: printk("__nfs_fhget: iget failed\n"); goto out; } int nfs_notify_change(struct dentry *dentry, struct iattr *attr) { struct inode *inode = dentry->d_inode; struct nfs_fattr fattr; int error; /* * Make sure the inode is up-to-date. */ error = nfs_revalidate(dentry); if (error) { #ifdef NFS_PARANOIA printk("nfs_notify_change: revalidate failed, error=%d\n", error); #endif goto out; } if (!S_ISREG(inode->i_mode)) attr->ia_valid &= ~ATTR_SIZE; error = nfs_wb_all(inode); if (error) goto out; error = nfs_proc_setattr(NFS_DSERVER(dentry), NFS_FH(dentry), &fattr, attr); if (error) goto out; /* * If we changed the size or mtime, update the inode * now to avoid invalidating the page cache. */ if (attr->ia_valid & ATTR_SIZE) { if (attr->ia_size != fattr.size) printk("nfs_notify_change: attr=%ld, fattr=%d??\n", attr->ia_size, fattr.size); inode->i_size = attr->ia_size; inode->i_mtime = fattr.mtime.seconds; } if (attr->ia_valid & ATTR_MTIME) inode->i_mtime = fattr.mtime.seconds; error = nfs_refresh_inode(inode, &fattr); out: return error; } /* * Wait for the inode to get unlocked. * (Used for NFS_INO_LOCKED and NFS_INO_REVALIDATING). */ int nfs_wait_on_inode(struct inode *inode, int flag) { struct task_struct *tsk = current; DECLARE_WAITQUEUE(wait, tsk); int intr, error = 0; intr = NFS_SERVER(inode)->flags & NFS_MOUNT_INTR; add_wait_queue(&inode->i_wait, &wait); for (;;) { set_task_state(tsk, (intr ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE)); error = 0; if (!(NFS_FLAGS(inode) & flag)) break; error = -ERESTARTSYS; if (intr && signalled()) break; schedule(); } set_task_state(tsk, TASK_RUNNING); remove_wait_queue(&inode->i_wait, &wait); return error; } /* * Externally visible revalidation function */ int nfs_revalidate(struct dentry *dentry) { return nfs_revalidate_inode(NFS_DSERVER(dentry), dentry); } /* * These are probably going to contain hooks for * allocating and releasing RPC credentials for * the file. I'll have to think about Tronds patch * a bit more.. */ int nfs_open(struct inode *inode, struct file *filp) { return 0; } int nfs_release(struct inode *inode, struct file *filp) { return 0; } /* * This function is called whenever some part of NFS notices that * the cached attributes have to be refreshed. */ int __nfs_revalidate_inode(struct nfs_server *server, struct dentry *dentry) { struct inode *inode = dentry->d_inode; int status = 0; struct nfs_fattr fattr; dfprintk(PAGECACHE, "NFS: revalidating %s/%s, ino=%ld\n", dentry->d_parent->d_name.name, dentry->d_name.name, inode->i_ino); if (!inode || is_bad_inode(inode)) return -ESTALE; while (NFS_REVALIDATING(inode)) { status = nfs_wait_on_inode(inode, NFS_INO_REVALIDATING); if (status < 0) return status; if (time_before(jiffies,NFS_READTIME(inode)+NFS_ATTRTIMEO(inode))) return 0; } NFS_FLAGS(inode) |= NFS_INO_REVALIDATING; status = nfs_proc_getattr(server, NFS_FH(dentry), &fattr); if (status) { int error; u32 *fh; struct nfs_fh fhandle; dfprintk(PAGECACHE, "nfs_revalidate_inode: %s/%s getattr failed, ino=%ld, error=%d\n", dentry->d_parent->d_name.name, dentry->d_name.name, inode->i_ino, status); if (status != -ESTALE) goto out; /* * A "stale filehandle" error ... show the current fh * and find out what the filehandle should be. */ fh = (u32 *) NFS_FH(dentry); dfprintk(PAGECACHE, "NFS: bad fh %08x%08x%08x%08x%08x%08x%08x%08x\n", fh[0],fh[1],fh[2],fh[3],fh[4],fh[5],fh[6],fh[7]); error = nfs_proc_lookup(server, NFS_FH(dentry->d_parent), dentry->d_name.name, &fhandle, &fattr); if (error) { dfprintk(PAGECACHE, "NFS: lookup failed, error=%d\n", error); goto out; } fh = (u32 *) &fhandle; dfprintk(PAGECACHE, " %08x%08x%08x%08x%08x%08x%08x%08x\n", fh[0],fh[1],fh[2],fh[3],fh[4],fh[5],fh[6],fh[7]); goto out; } status = nfs_refresh_inode(inode, &fattr); if (status) { dfprintk(PAGECACHE, "nfs_revalidate_inode: %s/%s refresh failed, ino=%ld, error=%d\n", dentry->d_parent->d_name.name, dentry->d_name.name, inode->i_ino, status); goto out; } dfprintk(PAGECACHE, "NFS: %s/%s revalidation complete\n", dentry->d_parent->d_name.name, dentry->d_name.name); out: NFS_FLAGS(inode) &= ~NFS_INO_REVALIDATING; wake_up(&inode->i_wait); return status; } /* * Many nfs protocol calls return the new file attributes after * an operation. Here we update the inode to reflect the state * of the server's inode. * * This is a bit tricky because we have to make sure all dirty pages * have been sent off to the server before calling invalidate_inode_pages. * To make sure no other process adds more write requests while we try * our best to flush them, we make them sleep during the attribute refresh. * * A very similar scenario holds for the dir cache. */ int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr) { int invalid = 0; int error = -EIO; dfprintk(VFS, "NFS: refresh_inode(%x/%ld ct=%d)\n", inode->i_dev, inode->i_ino, inode->i_count); if (!inode || !fattr) { printk("nfs_refresh_inode: inode or fattr is NULL\n"); goto out; } if (inode->i_ino != fattr->fileid) { printk("nfs_refresh_inode: mismatch, ino=%ld, fattr=%d\n", inode->i_ino, fattr->fileid); goto out; } /* * Make sure the inode's type hasn't changed. */ if ((inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT)) goto out_changed; inode->i_mode = fattr->mode; inode->i_nlink = fattr->nlink; inode->i_uid = fattr->uid; inode->i_gid = fattr->gid; inode->i_blocks = fattr->blocks; inode->i_atime = fattr->atime.seconds; inode->i_ctime = fattr->ctime.seconds; /* * Update the read time so we don't revalidate too often. */ NFS_READTIME(inode) = jiffies; error = 0; /* * If we have pending write-back entries, we don't want * to look at the size or the mtime the server sends us * too closely, as we're in the middle of modifying them. */ if (NFS_WRITEBACK(inode)) goto out; if (inode->i_size != fattr->size) { #ifdef NFS_DEBUG_VERBOSE printk("NFS: size change on %x/%ld\n", inode->i_dev, inode->i_ino); #endif inode->i_size = fattr->size; invalid = 1; } if (inode->i_mtime != fattr->mtime.seconds) { #ifdef NFS_DEBUG_VERBOSE printk("NFS: mtime change on %x/%ld\n", inode->i_dev, inode->i_ino); #endif inode->i_mtime = fattr->mtime.seconds; invalid = 1; } if (invalid) goto out_invalid; /* Update attrtimeo value */ if (fattr->mtime.seconds == NFS_OLDMTIME(inode)) { if ((NFS_ATTRTIMEO(inode) <<= 1) > NFS_MAXATTRTIMEO(inode)) NFS_ATTRTIMEO(inode) = NFS_MAXATTRTIMEO(inode); } NFS_OLDMTIME(inode) = fattr->mtime.seconds; out: return error; out_changed: /* * Big trouble! The inode has become a different object. */ #ifdef NFS_PARANOIA printk("nfs_refresh_inode: inode %ld mode changed, %07o to %07o\n", inode->i_ino, inode->i_mode, fattr->mode); #endif /* * No need to worry about unhashing the dentry, as the * lookup validation will know that the inode is bad. */ nfs_invalidate_inode(inode); goto out; out_invalid: #ifdef NFS_DEBUG_VERBOSE printk("nfs_refresh_inode: invalidating %ld pages\n", inode->i_nrpages); #endif nfs_zap_caches(inode); goto out; } /* * File system information */ static struct file_system_type nfs_fs_type = { "nfs", 0 /* FS_NO_DCACHE - this doesn't work right now*/, nfs_read_super, NULL }; extern int nfs_init_fhcache(void); extern int nfs_init_wreqcache(void); /* * Initialize NFS */ int init_nfs_fs(void) { int err; err = nfs_init_fhcache(); if (err) return err; err = nfs_init_wreqcache(); if (err) return err; #ifdef CONFIG_PROC_FS rpc_register_sysctl(); rpc_proc_init(); rpc_proc_register(&nfs_rpcstat); #endif return register_filesystem(&nfs_fs_type); } /* * Every kernel module contains stuff like this. */ #ifdef MODULE EXPORT_NO_SYMBOLS; /* Not quite true; I just maintain it */ MODULE_AUTHOR("Olaf Kirch "); int init_module(void) { return init_nfs_fs(); } void cleanup_module(void) { #ifdef CONFIG_PROC_FS rpc_proc_unregister("nfs"); #endif unregister_filesystem(&nfs_fs_type); } #endif