X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fllite%2Fsymlink.c;h=af463696348b3950101d7cbcea60952d2b652761;hp=93a4bdb9e931e61a271c46e5b33867201148a0b4;hb=8f0121ed09cf02dc12933bb3e880194b7ef0990e;hpb=7312616768bfed768ecc00ba20322c37568138d0 diff --git a/lustre/llite/symlink.c b/lustre/llite/symlink.c index 93a4bdb..af46369 100644 --- a/lustre/llite/symlink.c +++ b/lustre/llite/symlink.c @@ -1,38 +1,57 @@ /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- * vim:expandtab:shiftwidth=8:tabstop=8: * - * Copyright (c) 2002 Cluster File Systems, Inc. + * GPL HEADER START * - * This file is part of Lustre, http://www.lustre.org. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * - * Lustre is free software; you can redistribute it and/or - * modify it under the terms of version 2 of the GNU General Public - * License as published by the Free Software Foundation. + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 only, + * as published by the Free Software Foundation. * - * Lustre 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. + * 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 version 2 for more details (a copy is included + * in the LICENSE file that accompanied this code). * - * You should have received a copy of the GNU General Public License - * along with Lustre; if not, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * You should have received a copy of the GNU General Public License + * version 2 along with this program; If not, see + * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + * GPL HEADER END + */ +/* + * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. + * Use is subject to license terms. + */ +/* + * This file is part of Lustre, http://www.lustre.org/ + * Lustre is a trademark of Sun Microsystems, Inc. */ #include #include #include #include +#include #define DEBUG_SUBSYSTEM S_LLITE -#include +#include +#include "llite_internal.h" static int ll_readlink_internal(struct inode *inode, struct ptlrpc_request **request, char **symname) { struct ll_inode_info *lli = ll_i2info(inode); struct ll_sb_info *sbi = ll_i2sbi(inode); - int rc, symlen = inode->i_size + 1; + int rc, symlen = i_size_read(inode) + 1; + struct mdt_body *body; + struct md_op_data *op_data; ENTRY; *request = NULL; @@ -43,81 +62,150 @@ static int ll_readlink_internal(struct inode *inode, RETURN(0); } - rc = mdc_getattr(&sbi->ll_mdc_conn, inode->i_ino, S_IFLNK, - OBD_MD_LINKNAME, symlen, request); + op_data = ll_prep_md_op_data(NULL, inode, NULL, NULL, 0, symlen, + LUSTRE_OPC_ANY, NULL); + op_data->op_valid = OBD_MD_LINKNAME; + rc = md_getattr(sbi->ll_md_exp, op_data, request); + ll_finish_md_op_data(op_data); if (rc) { - CERROR("inode "LPD64": rc = %d\n", inode->i_ino, rc); - RETURN(rc); + if (rc != -ENOENT) + CERROR("inode %lu: rc = %d\n", inode->i_ino, rc); + GOTO (failed, rc); + } + + body = req_capsule_server_get(&(*request)->rq_pill, &RMF_MDT_BODY); + LASSERT(body != NULL); + if ((body->valid & OBD_MD_LINKNAME) == 0) { + CERROR("OBD_MD_LINKNAME not set on reply\n"); + GOTO(failed, rc = -EPROTO); } - *symname = lustre_msg_buf((*request)->rq_repmsg, 1); + LASSERT(symlen != 0); + if (body->eadatasize != symlen) { + CERROR("inode %lu: symlink length %d not expected %d\n", + inode->i_ino, body->eadatasize - 1, symlen - 1); + GOTO(failed, rc = -EPROTO); + } + + *symname = req_capsule_server_get(&(*request)->rq_pill, &RMF_MDT_MD); + if (*symname == NULL || + strnlen(*symname, symlen) != symlen - 1) { + /* not full/NULL terminated */ + CERROR("inode %lu: symlink not NULL terminated string" + "of length %d\n", inode->i_ino, symlen - 1); + GOTO(failed, rc = -EPROTO); + } OBD_ALLOC(lli->lli_symlink_name, symlen); /* do not return an error if we cannot cache the symlink locally */ - if (lli->lli_symlink_name) + if (lli->lli_symlink_name) { memcpy(lli->lli_symlink_name, *symname, symlen); - + *symname = lli->lli_symlink_name; + } RETURN(0); + +failed: + RETURN (rc); } static int ll_readlink(struct dentry *dentry, char *buffer, int buflen) { struct inode *inode = dentry->d_inode; - struct ll_inode_info *lli = ll_i2info(inode); struct ptlrpc_request *request; char *symname; int rc; ENTRY; + CDEBUG(D_VFSTRACE, "VFS Op\n"); /* on symlinks lli_open_sem protects lli_symlink_name allocation/data */ - down(&lli->lli_open_sem); + ll_inode_size_lock(inode, 0); rc = ll_readlink_internal(inode, &request, &symname); if (rc) GOTO(out, rc); rc = vfs_readlink(dentry, buffer, buflen, symname); out: - up(&lli->lli_open_sem); ptlrpc_req_finished(request); - + ll_inode_size_unlock(inode, 0); RETURN(rc); } -static int ll_follow_link(struct dentry *dentry, struct nameidata *nd, - struct lookup_intent *it) +#ifdef HAVE_COOKIE_FOLLOW_LINK +# define LL_FOLLOW_LINK_RETURN_TYPE void * +#else +# define LL_FOLLOW_LINK_RETURN_TYPE int +#endif + +static LL_FOLLOW_LINK_RETURN_TYPE ll_follow_link(struct dentry *dentry, + struct nameidata *nd) { struct inode *inode = dentry->d_inode; - struct ll_inode_info *lli = ll_i2info(inode); - struct ptlrpc_request *request; - int op, mode; - char *symname; + struct ptlrpc_request *request = NULL; int rc; + char *symname; ENTRY; - op = it->it_op; - mode = it->it_mode; - - ll_intent_release(dentry, it); - down(&lli->lli_open_sem); - - it->it_op = op; - it->it_mode = mode; - - rc = ll_readlink_internal(inode, &request, &symname); - if (rc) + CDEBUG(D_VFSTRACE, "VFS Op\n"); + /* Limit the recursive symlink depth to 5 instead of default + * 8 links when kernel has 4k stack to prevent stack overflow. + * For 8k stacks we need to limit it to 7 for local servers. */ + if (THREAD_SIZE < 8192 && current->link_count >= 6) { + rc = -ELOOP; + } else if (THREAD_SIZE == 8192 && current->link_count >= 8) { + rc = -ELOOP; + } else { + ll_inode_size_lock(inode, 0); + rc = ll_readlink_internal(inode, &request, &symname); + ll_inode_size_unlock(inode, 0); + } + if (rc) { + cfs_path_put(nd); /* Kernel assumes that ->follow_link() + releases nameidata on error */ GOTO(out, rc); + } - rc = vfs_follow_link_it(nd, symname, it); - out: - up(&lli->lli_open_sem); +#ifdef HAVE_COOKIE_FOLLOW_LINK + nd_set_link(nd, symname); + /* @symname may contain a pointer to the request message buffer, + we delay request releasing until ll_put_link then. */ + RETURN(request); +#else + if (lli->lli_symlink_name == NULL) { + /* falling back to recursive follow link if the request + * needs to be cleaned up still. */ + rc = vfs_follow_link(nd, symname); + GOTO(out, rc); + } + nd_set_link(nd, symname); + RETURN(0); +#endif +out: ptlrpc_req_finished(request); - +#ifdef HAVE_COOKIE_FOLLOW_LINK + RETURN(ERR_PTR(rc)); +#else RETURN(rc); +#endif +} + +#ifdef HAVE_COOKIE_FOLLOW_LINK +static void ll_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie) +{ + ptlrpc_req_finished(cookie); } +#endif -extern int ll_setattr(struct dentry *de, struct iattr *attr); struct inode_operations ll_fast_symlink_inode_operations = { - readlink: ll_readlink, - setattr: ll_setattr, - follow_link2: ll_follow_link + .readlink = ll_readlink, + .setattr = ll_setattr, + .follow_link = ll_follow_link, +#ifdef HAVE_COOKIE_FOLLOW_LINK + .put_link = ll_put_link, +#endif + .getattr = ll_getattr, + .permission = ll_inode_permission, + .setxattr = ll_setxattr, + .getxattr = ll_getxattr, + .listxattr = ll_listxattr, + .removexattr = ll_removexattr, };