X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fllite%2Fsymlink.c;h=70577cecc660c957b8f60e430969a6055ab332da;hp=ab87a92c67b9fa413245ff93b593b82e14cef62b;hb=e8e440b36aaf8e45649e72f7a92d2ebc1ae8d874;hpb=6f3d8ea4fc072430642aa93f31284ce89a09cb27 diff --git a/lustre/llite/symlink.c b/lustre/llite/symlink.c index ab87a92..70577ce 100644 --- a/lustre/llite/symlink.c +++ b/lustre/llite/symlink.c @@ -1,62 +1,242 @@ /* - * linux/fs/ext2/symlink.c + * GPL HEADER START * - * This code is issued under the GNU General Public License. - * See the file COPYING in this distribution + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * - * Copyright (C) 1992, 1993, 1994, 1995 - * Remy Card (card@masi.ibp.fr) - * Laboratoire MASI - Institut Blaise Pascal - * Universite Pierre et Marie Curie (Paris VI) + * 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. * - * Copyright (C) 1991, 1992 Linus Torvalds + * 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). * - * ext2 symlink handling code + * 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 * - * Modified for OBDFS: - * Copyright (C) 1999 Seagate Technology Inc. (author: braam@stelias.com) + * 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, 2014, 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 -#include /* for ENTRY and EXIT only */ -#include +#include "llite_internal.h" -static int ll_readlink(struct dentry *dentry, char *buffer, int buflen) +static int ll_readlink_internal(struct inode *inode, + struct ptlrpc_request **request, char **symname) { - struct ll_sb_info *sbi = ll_i2sbi(dentry->d_inode); - struct ptlrpc_request *request; - char *tmp; - int rc, size; + struct ll_inode_info *lli = ll_i2info(inode); + struct ll_sb_info *sbi = ll_i2sbi(inode); + int rc, symlen = i_size_read(inode) + 1; + struct mdt_body *body; + struct md_op_data *op_data; ENTRY; - rc = mdc_getattr(&sbi->ll_mds_client, sbi->ll_mds_conn, - dentry->d_inode->i_ino, S_IFLNK, - OBD_MD_LINKNAME, dentry->d_inode->i_size, &request); + *request = NULL; + + 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) { - CERROR("failure %d inode %ld\n", rc, - (long)dentry->d_inode->i_ino); - ptlrpc_free_req(request); - RETURN(rc); + if (rc != -ENOENT) + CERROR("%s: inode "DFID": rc = %d\n", + ll_get_fsname(inode->i_sb, NULL, 0), + PFID(ll_inode2fid(inode)), rc); + GOTO (failed, rc); + } + + body = req_capsule_server_get(&(*request)->rq_pill, &RMF_MDT_BODY); + LASSERT(body != NULL); + 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 = req_capsule_server_get(&(*request)->rq_pill, &RMF_MDT_MD); + if (*symname == NULL || + strnlen(*symname, symlen) != symlen - 1) { + /* not full/NULL terminated */ + 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); + } + + OBD_ALLOC(lli->lli_symlink_name, symlen); + /* do not return an error if we cannot cache the symlink locally */ + if (lli->lli_symlink_name) { + memcpy(lli->lli_symlink_name, *symname, symlen); + *symname = lli->lli_symlink_name; } + RETURN(0); + +failed: + RETURN (rc); +} + +#ifdef HAVE_SYMLINK_OPS_USE_NAMEIDATA +static void ll_put_link(struct dentry *dentry, + struct nameidata *nd, void *cookie) +#else +# ifdef HAVE_IOP_GET_LINK +static void ll_put_link(void *cookie) +# else +static void ll_put_link(struct inode *unused, void *cookie) +# endif +#endif +{ + ptlrpc_req_finished(cookie); +} + +#ifdef HAVE_SYMLINK_OPS_USE_NAMEIDATA +static void *ll_follow_link(struct dentry *dentry, struct nameidata *nd) +{ + struct inode *inode = dentry->d_inode; + struct ptlrpc_request *request = NULL; + int rc; + char *symname = NULL; + ENTRY; + + 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); + rc = ll_readlink_internal(inode, &request, &symname); + ll_inode_size_unlock(inode); + } + 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); +} +#else +# ifdef HAVE_IOP_GET_LINK +static const char *ll_get_link(struct dentry *dentry, + struct inode *inode, + struct delayed_call *done) +{ + struct ptlrpc_request *request; + char *symname = NULL; + int rc; + + ENTRY; + CDEBUG(D_VFSTRACE, "VFS Op\n"); + if (!dentry) + RETURN(ERR_PTR(-ECHILD)); + ll_inode_size_lock(inode); + rc = ll_readlink_internal(inode, &request, &symname); + ll_inode_size_unlock(inode); + if (rc < 0) { + ptlrpc_req_finished(request); + return ERR_PTR(rc); + } + + /* symname may contain a pointer to the request message buffer, + * we delay request releasing then. + */ + set_delayed_call(done, ll_put_link, request); + RETURN(symname); +} +# else +static const char *ll_follow_link(struct dentry *dentry, void **cookie) +{ + struct inode *inode = d_inode(dentry); + struct ptlrpc_request *request; + char *symname = NULL; + int rc; + ENTRY; - tmp = lustre_msg_buf(request->rq_repmsg, 1); - size = MIN(request->rq_repmsg->buflens[1], buflen); - rc = copy_to_user(buffer, tmp, size); - if (rc == 0) - rc = size; + CDEBUG(D_VFSTRACE, "VFS Op\n"); + ll_inode_size_lock(inode); + rc = ll_readlink_internal(inode, &request, &symname); + ll_inode_size_unlock(inode); + if (rc < 0) { + ptlrpc_req_finished(request); + return ERR_PTR(rc); + } - ptlrpc_free_req(request); - RETURN(rc); + /* symname may contain a pointer to the request message buffer, + * we delay request releasing until ll_put_link then. + */ + *cookie = request; + RETURN(symname); } +# endif /* HAVE_IOP_GET_LINK */ +#endif /* HAVE_SYMLINK_OPS_USE_NAMEIDATA */ -extern int ll_setattr(struct dentry *de, struct iattr *attr); struct inode_operations ll_fast_symlink_inode_operations = { - readlink: ll_readlink, - setattr: ll_setattr + .readlink = generic_readlink, + .setattr = ll_setattr, +#ifdef HAVE_IOP_GET_LINK + .get_link = ll_get_link, +#else + .follow_link = ll_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, };