Merge git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscache

* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscache: (41 commits)
  NFS: Add mount options to enable local caching on NFS
  NFS: Display local caching state
  NFS: Store pages from an NFS inode into a local cache
  NFS: Read pages from FS-Cache into an NFS inode
  NFS: nfs_readpage_async() needs to be accessible as a fallback for local caching
  NFS: Add read context retention for FS-Cache to call back with
  NFS: FS-Cache page management
  NFS: Add some new I/O counters for FS-Cache doing things for NFS
  NFS: Invalidate FsCache page flags when cache removed
  NFS: Use local disk inode cache
  NFS: Define and create inode-level cache objects
  NFS: Define and create superblock-level objects
  NFS: Define and create server-level objects
  NFS: Register NFS for caching and retrieve the top-level index
  NFS: Permit local filesystem caching to be enabled for NFS
  NFS: Add FS-Cache option bit and debug bit
  NFS: Add comment banners to some NFS functions
  FS-Cache: Make kAFS use FS-Cache
  CacheFiles: A cache that backs onto a mounted filesystem
  CacheFiles: Export things for CacheFiles
  ...

1 files changed, 103 insertions, 0 deletions

diff --git a/fs/fscache/netfs.c b/fs/fscache/netfs.c
new file mode 100644
index 000000000000..e028b8eb1c40
--- /dev/null
+++ b/fs/fscache/netfs.c
@@ -0,0 +1,103 @@
+/* FS-Cache netfs (client) registration
+ *
+ * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#define FSCACHE_DEBUG_LEVEL COOKIE
+#include <linux/module.h>
+#include <linux/slab.h>
+#include "internal.h"
+
+static LIST_HEAD(fscache_netfs_list);
+
+/*
+ * register a network filesystem for caching
+ */
+int __fscache_register_netfs(struct fscache_netfs *netfs)
+{
+        struct fscache_netfs *ptr;
+        int ret;
+
+        _enter("{%s}", netfs->name);
+
+        INIT_LIST_HEAD(&netfs->link);
+
+        /* allocate a cookie for the primary index */
+        netfs->primary_index =
+                kmem_cache_zalloc(fscache_cookie_jar, GFP_KERNEL);
+
+        if (!netfs->primary_index) {
+                _leave(" = -ENOMEM");
+                return -ENOMEM;
+        }
+
+        /* initialise the primary index cookie */
+        atomic_set(&netfs->primary_index->usage, 1);
+        atomic_set(&netfs->primary_index->n_children, 0);
+
+        netfs->primary_index->def               = &fscache_fsdef_netfs_def;
+        netfs->primary_index->parent            = &fscache_fsdef_index;
+        netfs->primary_index->netfs_data        = netfs;
+
+        atomic_inc(&netfs->primary_index->parent->usage);
+        atomic_inc(&netfs->primary_index->parent->n_children);
+
+        spin_lock_init(&netfs->primary_index->lock);
+        INIT_HLIST_HEAD(&netfs->primary_index->backing_objects);
+
+        /* check the netfs type is not already present */
+        down_write(&fscache_addremove_sem);
+
+        ret = -EEXIST;
+        list_for_each_entry(ptr, &fscache_netfs_list, link) {
+                if (strcmp(ptr->name, netfs->name) == 0)
+                        goto already_registered;
+        }
+
+        list_add(&netfs->link, &fscache_netfs_list);
+        ret = 0;
+
+        printk(KERN_NOTICE "FS-Cache: Netfs '%s' registered for caching\n",
+               netfs->name);
+
+already_registered:
+        up_write(&fscache_addremove_sem);
+
+        if (ret < 0) {
+                netfs->primary_index->parent = NULL;
+                __fscache_cookie_put(netfs->primary_index);
+                netfs->primary_index = NULL;
+        }
+
+        _leave(" = %d", ret);
+        return ret;
+}
+EXPORT_SYMBOL(__fscache_register_netfs);
+
+/*
+ * unregister a network filesystem from the cache
+ * - all cookies must have been released first
+ */
+void __fscache_unregister_netfs(struct fscache_netfs *netfs)
+{
+        _enter("{%s.%u}", netfs->name, netfs->version);
+
+        down_write(&fscache_addremove_sem);
+
+        list_del(&netfs->link);
+        fscache_relinquish_cookie(netfs->primary_index, 0);
+
+        up_write(&fscache_addremove_sem);
+
+        printk(KERN_NOTICE "FS-Cache: Netfs '%s' unregistered from caching\n",
+               netfs->name);
+
+        _leave("");
+}
+EXPORT_SYMBOL(__fscache_unregister_netfs);