LU-6158 mdt: always shrink_capsule in getxattr_all

[fs/lustre-release.git] / lustre / fld / fld_internal.h

diff --git a/lustre/fld/fld_internal.h b/lustre/fld/fld_internal.h
index 515cf88..3e25314 100644 (file)
--- a/lustre/fld/fld_internal.h
+++ b/lustre/fld/fld_internal.h
@@ -27,7 +27,7 @@
  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
- * Copyright (c) 2012, 2013, Intel Corporation.
+ * Copyright (c) 2012, 2014, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
@@ -35,6 +35,24 @@
  *
  * lustre/fld/fld_internal.h
  *
+ * Subsystem Description:
+ * FLD is FID Location Database, which stores where (IE, on which MDT)
+ * FIDs are located.
+ * The database is basically a record file, each record consists of a FID
+ * sequence range, MDT/OST index, and flags. The FLD for the whole FS
+ * is only stored on the sequence controller(MDT0) right now, but each target
+ * also has its local FLD, which only stores the local sequence.
+ *
+ * The FLD subsystem usually has two tasks:
+ * 1. maintain the database, i.e. when the sequence controller allocates
+ * new sequence ranges to some nodes, it will call the FLD API to insert the
+ * location information <sequence_range, node_index> in FLDB.
+ *
+ * 2. Handle requests from other nodes, i.e. if client needs to know where
+ * the FID is located, if it can not find the information in the local cache,
+ * it will send a FLD lookup RPC to the FLD service, and the FLD service will
+ * look up the FLDB entry and return the location information to client.
+ *
  * Author: Yury Umanets <umka@clusterfs.com>
  * Author: Tom WangDi <wangdi@clusterfs.com>
  */
@@ -46,11 +64,6 @@
 #include <libcfs/libcfs.h>
 #include <lustre_fld.h>
 
-enum {
-        LUSTRE_FLD_INIT = 1 << 0,
-        LUSTRE_FLD_RUN  = 1 << 1
-};
-
 struct fld_stats {
         __u64   fst_count;
         __u64   fst_cache;
@@ -130,11 +143,10 @@ enum {
 
 extern struct lu_fld_hash fld_hash[];
 
-#ifdef __KERNEL__
 
-#ifdef LPROCFS
+#ifdef CONFIG_PROC_FS
 extern struct proc_dir_entry *fld_type_proc_dir;
-extern struct lprocfs_seq_vars fld_client_proc_list[];
+extern struct lprocfs_vars fld_client_proc_list[];
 #endif
 
 # ifdef HAVE_SERVER_SUPPORT
@@ -161,7 +173,7 @@ int fld_index_create(const struct lu_env *env, struct lu_server_fld *fld,
                     const struct lu_seq_range *new_range, struct thandle *th);
 
 int fld_index_lookup(const struct lu_env *env, struct lu_server_fld *fld,
-                    seqno_t seq, struct lu_seq_range *range);
+                    u64 seq, struct lu_seq_range *range);
 
 int fld_name_to_index(const char *name, __u32 *index);
 int fld_server_mod_init(void);
@@ -170,9 +182,9 @@ void fld_server_mod_exit(void);
 
 int fld_server_read(const struct lu_env *env, struct lu_server_fld *fld,
                    struct lu_seq_range *range, void *data, int data_len);
-#ifdef LPROCFS
+#ifdef CONFIG_PROC_FS
 extern const struct file_operations fld_proc_seq_fops;
-extern struct lprocfs_seq_vars fld_server_proc_list[];
+extern struct lprocfs_vars fld_server_proc_list[];
 #endif
 
 # endif /* HAVE_SERVER_SUPPORT */
@@ -180,7 +192,6 @@ extern struct lprocfs_seq_vars fld_server_proc_list[];
 int fld_client_rpc(struct obd_export *exp,
                    struct lu_seq_range *range, __u32 fld_op,
                   struct ptlrpc_request **reqp);
-#endif /* __KERNEL__ */
 
 struct fld_cache *fld_cache_init(const char *name,
                                  int cache_size, int cache_threshold);
@@ -202,7 +213,7 @@ void fld_cache_delete(struct fld_cache *cache,
 void fld_cache_delete_nolock(struct fld_cache *cache,
                             const struct lu_seq_range *range);
 int fld_cache_lookup(struct fld_cache *cache,
-                     const seqno_t seq, struct lu_seq_range *range);
+                    const u64 seq, struct lu_seq_range *range);
 
 struct fld_cache_entry *
 fld_cache_entry_lookup(struct fld_cache *cache,