update snapfs 1)add mntget and mntput for snap_current when mount snap_clone 2)get...

[fs/lustre-release.git] / lustre / snapfs / cache.c

diff --git a/lustre/snapfs/cache.c b/lustre/snapfs/cache.c
index d0c8f1b..68efe98 100644 (file)
--- a/lustre/snapfs/cache.c
+++ b/lustre/snapfs/cache.c
@@ -1,56 +1,35 @@
-/*
- *
- *
- *  Copyright (C) 2000 Stelias Computing, Inc.
- *  Copyright (C) 2000 Red Hat, Inc.
- *
- *
+/*  
+ *  snapfs/cache.c
  */
 
+#define DEBUG_SUBSYSTEM S_SNAP
 
-#include <stdarg.h>
-
-#include <asm/bitops.h>
-#include <asm/uaccess.h>
-#include <asm/system.h>
-
-#include <linux/errno.h>
+#include <linux/kmod.h>
+#include <linux/init.h>
 #include <linux/fs.h>
-#include <linux/ext2_fs.h>
-#include <linux/malloc.h>
-#include <linux/vmalloc.h>
-#include <linux/sched.h>
-#include <linux/stat.h>
+#include <linux/slab.h>
 #include <linux/string.h>
-#include <linux/locks.h>
-#include <linux/blkdev.h>
-#include <linux/init.h>
-#define __NO_VERSION__
-#include <linux/module.h>
-
-#include <linux/filter.h>
-#include <linux/snapfs.h>
-#include <linux/snapsupport.h>
-
+#include <linux/jbd.h>
+#include <linux/ext3_fs.h>
+#include <linux/snap.h>
+#include <portals/list.h>
+#include "snapfs_internal.h" 
 /*
  * XXX - Not sure for snapfs that the cache functions are even needed.
  * Can't all lookups be done by an inode->superblock->u.generic_sbp
  * lookup?
  */
 
-/*
-   This file contains the routines associated with managing a
-   cache of files .  These caches need to be found
-   fast so they are hashed by the device, with an attempt to have
-   collision chains of length 1.
-*/
+extern struct snap_table snap_tables[SNAP_MAX_TABLES];
 
 /* the intent of this hash is to have collision chains of length 1 */
 #define CACHES_BITS 8
 #define CACHES_SIZE (1 << CACHES_BITS)
 #define CACHES_MASK CACHES_SIZE - 1
+
 static struct list_head snap_caches[CACHES_SIZE];
 
+
 static inline int snap_cache_hash(kdev_t dev)
 {
        return (CACHES_MASK) & ((0x000F & (dev)) + ((0x0F00 & (dev)) >>8));
@@ -75,62 +54,46 @@ inline void snap_init_cache_hash(void)
 struct snap_cache *snap_find_cache(kdev_t dev)
 {
        struct snap_cache *cache;
-       struct list_head *lh, *tmp;
+       struct list_head *lh;
 
-       lh = tmp = &(snap_caches[snap_cache_hash(dev)]);
-       while ( (tmp = lh->next) != lh ) {
-               cache = list_entry(tmp, struct snap_cache, cache_chain);
+       lh = &(snap_caches[snap_cache_hash(dev)]);
+        list_for_each_entry(cache, lh, cache_chain) { 
                if ( cache->cache_dev == dev )
                        return cache;
        }
        return NULL;
 }
 
-
-/* map an inode to a cache */
-struct snap_cache *snap_get_cache(struct inode *inode)
-{
-       struct snap_cache *cache;
-
-       /* find the correct snap_cache here, based on the device */
-       cache = snap_find_cache(inode->i_dev);
-       if ( !cache ) {
-               printk("WARNING: no  cache for dev %d, ino %ld\n",
-                      inode->i_dev, inode->i_ino);
-               return NULL;
-       }
-
-       return cache;
-}
-
-
-/* another debugging routine: check fs is InterMezzo fs */
-int snap_ispresto(struct inode *inode)
-{
-       struct snap_cache *cache;
-
-       if ( !inode )
-               return 0;
-       cache = snap_get_cache(inode);
-       if ( !cache )
-               return 0;
-       return (inode->i_dev == cache->cache_dev);
-}
-
 /* setup a cache structure when we need one */
 struct snap_cache *snap_init_cache(void)
 {
        struct snap_cache *cache;
 
        /* make a snap_cache structure for the hash */
-       SNAP_ALLOC(cache, struct snap_cache *, sizeof(struct snap_cache));
+       SNAP_ALLOC(cache,  sizeof(struct snap_cache));
        if ( cache ) {
-               memset(cache, 0, sizeof(struct snap_cache));
+                memset(cache, 0, sizeof(struct snap_cache));
                INIT_LIST_HEAD(&cache->cache_chain);
                INIT_LIST_HEAD(&cache->cache_clone_list);
-       }
+        }
        return cache;
 }
+/*walk through the cache structure*/
+int snap_cache_process(snap_cache_cb_t cb, void* in, unsigned long* out)
+{
+       int i = 0;
+
+       for (i = 0; i < CACHES_SIZE; i++) {
+               struct snap_cache *cache;
+               struct list_head *lh = &(snap_caches[i]);
+               list_for_each_entry(cache, lh, cache_chain) {   
+                       if (cb(cache, in, out))
+                               goto exit;
+               }
+       }
+exit:
+       return 0;
+}
 
 
 /* free a cache structure and all of the memory it is pointing to */
@@ -138,8 +101,6 @@ inline void snap_free_cache(struct snap_cache *cache)
 {
        if (!cache)
                return;
-
-
        SNAP_FREE(cache, sizeof(struct snap_cache));
 }