Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / ocfs2 / sysfile.c
diff --git a/kernel/fs/ocfs2/sysfile.c b/kernel/fs/ocfs2/sysfile.c
new file mode 100644 (file)
index 0000000..af155c1
--- /dev/null
@@ -0,0 +1,182 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * sysfile.c
+ *
+ * Initialize, read, write, etc. system files.
+ *
+ * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/types.h>
+#include <linux/highmem.h>
+
+#include <cluster/masklog.h>
+
+#include "ocfs2.h"
+
+#include "alloc.h"
+#include "dir.h"
+#include "inode.h"
+#include "journal.h"
+#include "sysfile.h"
+
+#include "buffer_head_io.h"
+
+static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb,
+                                                  int type,
+                                                  u32 slot);
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+static struct lock_class_key ocfs2_sysfile_cluster_lock_key[NUM_SYSTEM_INODES];
+#endif
+
+static inline int is_global_system_inode(int type)
+{
+       return type >= OCFS2_FIRST_ONLINE_SYSTEM_INODE &&
+               type <= OCFS2_LAST_GLOBAL_SYSTEM_INODE;
+}
+
+static struct inode **get_local_system_inode(struct ocfs2_super *osb,
+                                            int type,
+                                            u32 slot)
+{
+       int index;
+       struct inode **local_system_inodes, **free = NULL;
+
+       BUG_ON(slot == OCFS2_INVALID_SLOT);
+       BUG_ON(type < OCFS2_FIRST_LOCAL_SYSTEM_INODE ||
+              type > OCFS2_LAST_LOCAL_SYSTEM_INODE);
+
+       spin_lock(&osb->osb_lock);
+       local_system_inodes = osb->local_system_inodes;
+       spin_unlock(&osb->osb_lock);
+
+       if (unlikely(!local_system_inodes)) {
+               local_system_inodes = kzalloc(sizeof(struct inode *) *
+                                             NUM_LOCAL_SYSTEM_INODES *
+                                             osb->max_slots,
+                                             GFP_NOFS);
+               if (!local_system_inodes) {
+                       mlog_errno(-ENOMEM);
+                       /*
+                        * return NULL here so that ocfs2_get_sytem_file_inodes
+                        * will try to create an inode and use it. We will try
+                        * to initialize local_system_inodes next time.
+                        */
+                       return NULL;
+               }
+
+               spin_lock(&osb->osb_lock);
+               if (osb->local_system_inodes) {
+                       /* Someone has initialized it for us. */
+                       free = local_system_inodes;
+                       local_system_inodes = osb->local_system_inodes;
+               } else
+                       osb->local_system_inodes = local_system_inodes;
+               spin_unlock(&osb->osb_lock);
+               kfree(free);
+       }
+
+       index = (slot * NUM_LOCAL_SYSTEM_INODES) +
+               (type - OCFS2_FIRST_LOCAL_SYSTEM_INODE);
+
+       return &local_system_inodes[index];
+}
+
+struct inode *ocfs2_get_system_file_inode(struct ocfs2_super *osb,
+                                         int type,
+                                         u32 slot)
+{
+       struct inode *inode = NULL;
+       struct inode **arr = NULL;
+
+       /* avoid the lookup if cached in local system file array */
+       if (is_global_system_inode(type)) {
+               arr = &(osb->global_system_inodes[type]);
+       } else
+               arr = get_local_system_inode(osb, type, slot);
+
+       mutex_lock(&osb->system_file_mutex);
+       if (arr && ((inode = *arr) != NULL)) {
+               /* get a ref in addition to the array ref */
+               inode = igrab(inode);
+               mutex_unlock(&osb->system_file_mutex);
+               BUG_ON(!inode);
+
+               return inode;
+       }
+
+       /* this gets one ref thru iget */
+       inode = _ocfs2_get_system_file_inode(osb, type, slot);
+
+       /* add one more if putting into array for first time */
+       if (arr && inode) {
+               *arr = igrab(inode);
+               BUG_ON(!*arr);
+       }
+       mutex_unlock(&osb->system_file_mutex);
+       return inode;
+}
+
+static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb,
+                                                  int type,
+                                                  u32 slot)
+{
+       char namebuf[40];
+       struct inode *inode = NULL;
+       u64 blkno;
+       int status = 0;
+
+       ocfs2_sprintf_system_inode_name(namebuf,
+                                       sizeof(namebuf),
+                                       type, slot);
+
+       status = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf,
+                                           strlen(namebuf), &blkno);
+       if (status < 0) {
+               goto bail;
+       }
+
+       inode = ocfs2_iget(osb, blkno, OCFS2_FI_FLAG_SYSFILE, type);
+       if (IS_ERR(inode)) {
+               mlog_errno(PTR_ERR(inode));
+               inode = NULL;
+               goto bail;
+       }
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       if (type == LOCAL_USER_QUOTA_SYSTEM_INODE ||
+           type == LOCAL_GROUP_QUOTA_SYSTEM_INODE ||
+           type == JOURNAL_SYSTEM_INODE) {
+               /* Ignore inode lock on these inodes as the lock does not
+                * really belong to any process and lockdep cannot handle
+                * that */
+               OCFS2_I(inode)->ip_inode_lockres.l_lockdep_map.key = NULL;
+       } else {
+               lockdep_init_map(&OCFS2_I(inode)->ip_inode_lockres.
+                                                               l_lockdep_map,
+                                ocfs2_system_inodes[type].si_name,
+                                &ocfs2_sysfile_cluster_lock_key[type], 0);
+       }
+#endif
+bail:
+
+       return inode;
+}
+