LU-709 build: clean up quota_read, follow_link and RCU

[fs/lustre-release.git] / lustre / llite / symlink.c

diff --git a/lustre/llite/symlink.c b/lustre/llite/symlink.c
index af46369..67a3107 100644 (file)
--- a/lustre/llite/symlink.c
+++ b/lustre/llite/symlink.c
@@ -1,6 +1,4 @@
-/* -*- 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.
@@ -28,6 +26,8 @@
 /*
  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, Whamcloud, Inc.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
@@ -37,7 +37,6 @@
 #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
 
@@ -56,14 +55,24 @@ static int ll_readlink_internal(struct inode *inode,
 
         *request = NULL;
 
-        if (lli->lli_symlink_name) {
-                *symname = lli->lli_symlink_name;
-                CDEBUG(D_INODE, "using cached symlink %s\n", *symname);
-                RETURN(0);
-        }
+       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);
@@ -117,8 +126,8 @@ static int ll_readlink(struct dentry *dentry, char *buffer, int buflen)
         ENTRY;
 
         CDEBUG(D_VFSTRACE, "VFS Op\n");
-        /* on symlinks lli_open_sem protects lli_symlink_name allocation/data */
-        ll_inode_size_lock(inode, 0);
+
+       ll_inode_size_lock(inode);
         rc = ll_readlink_internal(inode, &request, &symname);
         if (rc)
                 GOTO(out, rc);
@@ -126,24 +135,17 @@ static int ll_readlink(struct dentry *dentry, char *buffer, int buflen)
         rc = vfs_readlink(dentry, buffer, buflen, symname);
  out:
         ptlrpc_req_finished(request);
-        ll_inode_size_unlock(inode, 0);
-        RETURN(rc);
+       ll_inode_size_unlock(inode);
+       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)
+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;
-        ENTRY;
+       struct inode *inode = dentry->d_inode;
+       struct ptlrpc_request *request = NULL;
+       int rc;
+       char *symname;
+       ENTRY;
 
         CDEBUG(D_VFSTRACE, "VFS Op\n");
         /* Limit the recursive symlink depth to 5 instead of default
@@ -154,9 +156,9 @@ static LL_FOLLOW_LINK_RETURN_TYPE ll_follow_link(struct dentry *dentry,
         } 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);
+               ll_inode_size_lock(inode);
+               rc = ll_readlink_internal(inode, &request, &symname);
+               ll_inode_size_unlock(inode);
         }
         if (rc) {
                 cfs_path_put(nd); /* Kernel assumes that ->follow_link()
@@ -164,48 +166,30 @@ static LL_FOLLOW_LINK_RETURN_TYPE ll_follow_link(struct dentry *dentry,
                 GOTO(out, rc);
         }
 
-#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
+       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);
 out:
-        ptlrpc_req_finished(request);
-#ifdef HAVE_COOKIE_FOLLOW_LINK
-        RETURN(ERR_PTR(rc));
-#else
-        RETURN(rc);
-#endif
+       ptlrpc_req_finished(request);
+       RETURN(ERR_PTR(rc));
 }
 
-#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,
-        .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,
+       .readlink       = ll_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,
 };