diff options
Diffstat (limited to 'fs/afs/callback.c')
| -rw-r--r-- | fs/afs/callback.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/fs/afs/callback.c b/fs/afs/callback.c new file mode 100644 index 000000000000..2fd62f89ae01 --- /dev/null +++ b/fs/afs/callback.c @@ -0,0 +1,168 @@ +/* + * Copyright (c) 2002 Red Hat, Inc. All rights reserved. + * + * This software may be freely redistributed under the terms of the + * GNU General Public License. + * + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Authors: David Woodhouse <dwmw2@cambridge.redhat.com> + * David Howells <dhowells@redhat.com> + * + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include "server.h" +#include "vnode.h" +#include "internal.h" + +/*****************************************************************************/ +/* + * allow the fileserver to request callback state (re-)initialisation + */ +int SRXAFSCM_InitCallBackState(struct afs_server *server) +{ + struct list_head callbacks; + + _enter("%p", server); + + INIT_LIST_HEAD(&callbacks); + + /* transfer the callback list from the server to a temp holding area */ + spin_lock(&server->cb_lock); + + list_add(&callbacks, &server->cb_promises); + list_del_init(&server->cb_promises); + + /* munch our way through the list, grabbing the inode, dropping all the + * locks and regetting them in the right order + */ + while (!list_empty(&callbacks)) { + struct afs_vnode *vnode; + struct inode *inode; + + vnode = list_entry(callbacks.next, struct afs_vnode, cb_link); + list_del_init(&vnode->cb_link); + + /* try and grab the inode - may fail */ + inode = igrab(AFS_VNODE_TO_I(vnode)); + if (inode) { + int release = 0; + + spin_unlock(&server->cb_lock); + spin_lock(&vnode->lock); + + if (vnode->cb_server == server) { + vnode->cb_server = NULL; + afs_kafstimod_del_timer(&vnode->cb_timeout); + spin_lock(&afs_cb_hash_lock); + list_del_init(&vnode->cb_hash_link); + spin_unlock(&afs_cb_hash_lock); + release = 1; + } + + spin_unlock(&vnode->lock); + + iput(inode); + afs_put_server(server); + + spin_lock(&server->cb_lock); + } + } + + spin_unlock(&server->cb_lock); + + _leave(" = 0"); + return 0; +} /* end SRXAFSCM_InitCallBackState() */ + +/*****************************************************************************/ +/* + * allow the fileserver to break callback promises + */ +int SRXAFSCM_CallBack(struct afs_server *server, size_t count, + struct afs_callback callbacks[]) +{ + _enter("%p,%u,", server, count); + + for (; count > 0; callbacks++, count--) { + struct afs_vnode *vnode = NULL; + struct inode *inode = NULL; + int valid = 0; + + _debug("- Fid { vl=%08x n=%u u=%u } CB { v=%u x=%u t=%u }", + callbacks->fid.vid, + callbacks->fid.vnode, + callbacks->fid.unique, + callbacks->version, + callbacks->expiry, + callbacks->type + ); + + /* find the inode for this fid */ + spin_lock(&afs_cb_hash_lock); + + list_for_each_entry(vnode, + &afs_cb_hash(server, &callbacks->fid), + cb_hash_link) { + if (memcmp(&vnode->fid, &callbacks->fid, + sizeof(struct afs_fid)) != 0) + continue; + + /* right vnode, but is it same server? */ + if (vnode->cb_server != server) + break; /* no */ + + /* try and nail the inode down */ + inode = igrab(AFS_VNODE_TO_I(vnode)); + break; + } + + spin_unlock(&afs_cb_hash_lock); + + if (inode) { + /* we've found the record for this vnode */ + spin_lock(&vnode->lock); + if (vnode->cb_server == server) { + /* the callback _is_ on the calling server */ + vnode->cb_server = NULL; + valid = 1; + + afs_kafstimod_del_timer(&vnode->cb_timeout); + vnode->flags |= AFS_VNODE_CHANGED; + + spin_lock(&server->cb_lock); + list_del_init(&vnode->cb_link); + spin_unlock(&server->cb_lock); + + spin_lock(&afs_cb_hash_lock); + list_del_init(&vnode->cb_hash_link); + spin_unlock(&afs_cb_hash_lock); + } + spin_unlock(&vnode->lock); + + if (valid) { + invalidate_remote_inode(inode); + afs_put_server(server); + } + iput(inode); + } + } + + _leave(" = 0"); + return 0; +} /* end SRXAFSCM_CallBack() */ + +/*****************************************************************************/ +/* + * allow the fileserver to see if the cache manager is still alive + */ +int SRXAFSCM_Probe(struct afs_server *server) +{ + _debug("SRXAFSCM_Probe(%p)\n", server); + return 0; +} /* end SRXAFSCM_Probe() */ |