X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fllite%2Fsymlink.c;h=e394efa327e0b81f507295fddd0076a9c5e012bc;hp=232ff19ee92d91cfd225ba86ddcf51b08f18f678;hb=71f7a897f96307e22b57c6527881ef90d10ef2c5;hpb=eef822668e9c4794fc5f06747e03985518fa1d19;ds=sidebyside diff --git a/lustre/llite/symlink.c b/lustre/llite/symlink.c index 232ff19..e394efa 100644 --- a/lustre/llite/symlink.c +++ b/lustre/llite/symlink.c @@ -1,28 +1,42 @@ -/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- - * vim:expandtab:shiftwidth=8:tabstop=8: +/* + * GPL HEADER START * - * Copyright (c) 2002 Cluster File Systems, Inc. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * - * This file is part of Lustre, http://www.lustre.org. + * 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 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 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). * - * 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. + * 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 * - * 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. + * 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. + * + * Copyright (c) 2011, 2012, Intel Corporation. + */ +/* + * 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 @@ -36,51 +50,63 @@ static int ll_readlink_internal(struct inode *inode, struct ll_sb_info *sbi = ll_i2sbi(inode); int rc, symlen = i_size_read(inode) + 1; struct mdt_body *body; - struct obd_capa *oc; + struct md_op_data *op_data; ENTRY; *request = NULL; - if (lli->lli_symlink_name) { - *symname = lli->lli_symlink_name; - CDEBUG(D_INODE, "using cached symlink %s\n", *symname); - RETURN(0); - } - - oc = ll_mdscapa_get(inode); - rc = md_getattr(sbi->ll_md_exp, ll_inode2fid(inode), oc, - OBD_MD_LINKNAME, symlen, request); - capa_put(oc); + if (lli->lli_symlink_name) { + int print_limit = min_t(int, PAGE_SIZE - 128, symlen); + + *symname = lli->lli_symlink_name; + /* If the total CDEBUG() size is larger than a page, it + * will print a warning to the console, avoid this by + * printing just the last part of the symlink. */ + CDEBUG(D_INODE, "using cached symlink %s%.*s, len = %d\n", + print_limit < symlen ? "..." : "", print_limit, + (*symname) + symlen - print_limit, symlen); + RETURN(0); + } + + op_data = ll_prep_md_op_data(NULL, inode, NULL, NULL, 0, symlen, + LUSTRE_OPC_ANY, NULL); + if (IS_ERR(op_data)) + RETURN(PTR_ERR(op_data)); + + 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) { if (rc != -ENOENT) - CERROR("inode %lu: rc = %d\n", inode->i_ino, rc); + CERROR("%s: inode "DFID": rc = %d\n", + ll_get_fsname(inode->i_sb, NULL, 0), + PFID(ll_inode2fid(inode)), rc); GOTO (failed, rc); } - body = lustre_msg_buf((*request)->rq_repmsg, REPLY_REC_OFF, - sizeof(*body)); + body = req_capsule_server_get(&(*request)->rq_pill, &RMF_MDT_BODY); LASSERT(body != NULL); - LASSERT_REPSWABBED(*request, REPLY_REC_OFF); - - if ((body->valid & OBD_MD_LINKNAME) == 0) { - CERROR("OBD_MD_LINKNAME not set on reply\n"); - GOTO(failed, rc = -EPROTO); - } - - 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); + if ((body->mbo_valid & OBD_MD_LINKNAME) == 0) { + CERROR("OBD_MD_LINKNAME not set on reply\n"); + GOTO(failed, rc = -EPROTO); + } + + LASSERT(symlen != 0); + if (body->mbo_eadatasize != symlen) { + CERROR("%s: inode "DFID": symlink length %d not expected %d\n", + ll_get_fsname(inode->i_sb, NULL, 0), + PFID(ll_inode2fid(inode)), body->mbo_eadatasize - 1, + symlen - 1); GOTO(failed, rc = -EPROTO); } - *symname = lustre_msg_buf((*request)->rq_repmsg, REPLY_REC_OFF + 1, - symlen); + *symname = req_capsule_server_get(&(*request)->rq_pill, &RMF_MDT_MD); if (*symname == NULL || - strnlen (*symname, symlen) != symlen - 1) { + 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); + CERROR("%s: inode "DFID": symlink not NULL terminated string" + "of length %d\n", ll_get_fsname(inode->i_sb, NULL, 0), + PFID(ll_inode2fid(inode)), symlen - 1); GOTO(failed, rc = -EPROTO); } @@ -88,134 +114,62 @@ static int ll_readlink_internal(struct inode *inode, /* do not return an error if we cannot cache the symlink locally */ if (lli->lli_symlink_name) { memcpy(lli->lli_symlink_name, *symname, symlen); - ptlrpc_req_finished (*request); - *request = NULL; *symname = lli->lli_symlink_name; } - RETURN(0); - failed: - ptlrpc_req_finished (*request); +failed: RETURN (rc); } -static int ll_readlink(struct dentry *dentry, char *buffer, int buflen) +static void *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; - char *symname; - int rc; - ENTRY; + struct inode *inode = dentry->d_inode; + struct ptlrpc_request *request = NULL; + int rc; + char *symname = NULL; + ENTRY; CDEBUG(D_VFSTRACE, "VFS Op\n"); - /* on symlinks lli_open_sem protects lli_symlink_name allocation/data */ - down(&lli->lli_size_sem); - rc = ll_readlink_internal(inode, &request, &symname); - if (rc) - GOTO(out, rc); - - rc = vfs_readlink(dentry, buffer, buflen, symname); - ptlrpc_req_finished(request); - out: - up(&lli->lli_size_sem); - RETURN(rc); -} - -#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); -#ifdef LUSTRE_KERNEL_VERSION - struct lookup_intent *it = ll_nd2it(nd); -#endif - struct ptlrpc_request *request; - int rc; - char *symname; - ENTRY; - -#ifdef LUSTRE_KERNEL_VERSION - if (it != NULL) { - int op = it->it_op; - int mode = it->it_create_mode; - - ll_intent_release(it); - it->it_op = op; - it->it_create_mode = mode; + /* 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); + rc = ll_readlink_internal(inode, &request, &symname); + ll_inode_size_unlock(inode); } -#endif - - CDEBUG(D_VFSTRACE, "VFS Op\n"); - down(&lli->lli_size_sem); - rc = ll_readlink_internal(inode, &request, &symname); - up(&lli->lli_size_sem); - if (rc) { - path_release(nd); /* Kernel assumes that ->follow_link() - releases nameidata on error */ - GOTO(out, rc); - } - -#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,8)) - rc = vfs_follow_link(nd, symname); -#else -#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 (request != 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 -#endif -out: - ptlrpc_req_finished(request); -#ifdef HAVE_COOKIE_FOLLOW_LINK - RETURN(ERR_PTR(rc)); -#else - RETURN(rc); -#endif + if (rc) { + ptlrpc_req_finished(request); + request = NULL; + symname = ERR_PTR(rc); + } + + 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); } -#ifdef HAVE_COOKIE_FOLLOW_LINK static void ll_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie) { - ptlrpc_req_finished(cookie); + ptlrpc_req_finished(cookie); } -#endif struct inode_operations ll_fast_symlink_inode_operations = { - .readlink = ll_readlink, - .setattr = ll_setattr, -#ifdef LUSTRE_KERNEL_VERSION - .setattr_raw = ll_setattr_raw, -#endif - .follow_link = ll_follow_link, -#ifdef HAVE_COOKIE_FOLLOW_LINK - .put_link = ll_put_link, -#endif -#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)) - .revalidate_it = ll_inode_revalidate_it, -#else - .getattr = ll_getattr, -#endif - .permission = ll_inode_permission, - .setxattr = ll_setxattr, - .getxattr = ll_getxattr, - .listxattr = ll_listxattr, - .removexattr = ll_removexattr, + .readlink = generic_readlink, + .setattr = ll_setattr, + .follow_link = ll_follow_link, + .put_link = ll_put_link, + .getattr = ll_getattr, + .permission = ll_inode_permission, + .setxattr = ll_setxattr, + .getxattr = ll_getxattr, + .listxattr = ll_listxattr, + .removexattr = ll_removexattr, };