-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
+/*
* GPL HEADER START
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
* in the LICENSE file that accompanied this code).
*
* You should have received a copy of the GNU General Public License
- * version 2 along with this program; If not, see [sun.com URL with a
- * copy of GPLv2].
+ * 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
* GPL HEADER END
*/
/*
- * Copyright 2008 Sun Microsystems, Inc. All rights reserved
+ * 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/
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/stat.h>
-#include <linux/smp_lock.h>
#include <linux/version.h>
#define DEBUG_SUBSYSTEM S_LLITE
-#include <lustre_lite.h>
#include "llite_internal.h"
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 = 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);
- }
-
- 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);
}
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);
+ 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);
}
/* 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)
-{
- 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_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 *
+#ifdef HAVE_SYMLINK_OPS_USE_NAMEIDATA
+static void ll_put_link(struct dentry *dentry,
+ struct nameidata *nd, void *cookie)
#else
-# define LL_FOLLOW_LINK_RETURN_TYPE int
+# 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
-
-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 HAVE_VFS_INTENT_PATCHES
- struct lookup_intent *it = ll_nd2it(nd);
-#endif
- struct ptlrpc_request *request;
- int rc;
- char *symname;
- ENTRY;
-
-#ifdef HAVE_VFS_INTENT_PATCHES
- if (it != NULL) {
- int op = it->it_op;
- int mode = it->it_create_mode;
+ ptlrpc_req_finished(cookie);
+}
- ll_intent_release(it);
- it->it_op = op;
- it->it_create_mode = mode;
- }
-#endif
+#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");
- 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);
+ /* 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);
}
- nd_set_link(nd, symname);
- RETURN(0);
-#endif
-#endif
-out:
- ptlrpc_req_finished(request);
-#ifdef HAVE_COOKIE_FOLLOW_LINK
- RETURN(ERR_PTR(rc));
+ 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
- RETURN(rc);
-#endif
+# 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);
}
-
-#ifdef HAVE_COOKIE_FOLLOW_LINK
-static void ll_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
+# else
+static const char *ll_follow_link(struct dentry *dentry, void **cookie)
{
- ptlrpc_req_finished(cookie);
+ struct inode *inode = d_inode(dentry);
+ struct ptlrpc_request *request;
+ char *symname = NULL;
+ int rc;
+ ENTRY;
+
+ 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);
+ }
+
+ /* symname may contain a pointer to the request message buffer,
+ * we delay request releasing until ll_put_link then.
+ */
+ *cookie = request;
+ RETURN(symname);
}
-#endif
+# endif /* HAVE_IOP_GET_LINK */
+#endif /* HAVE_SYMLINK_OPS_USE_NAMEIDATA */
struct inode_operations ll_fast_symlink_inode_operations = {
- .readlink = ll_readlink,
- .setattr = ll_setattr,
-#ifdef HAVE_VFS_INTENT_PATCHES
- .setattr_raw = ll_setattr_raw,
-#endif
- .follow_link = ll_follow_link,
-#ifdef HAVE_COOKIE_FOLLOW_LINK
- .put_link = ll_put_link,
+ .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,
+ .getattr = ll_getattr,
+ .permission = ll_inode_permission,
+ .setxattr = ll_setxattr,
+ .getxattr = ll_getxattr,
+ .listxattr = ll_listxattr,
+ .removexattr = ll_removexattr,
};