From 515d86117724abe39d7d57d7ccc7cc5c44480529 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 23 Dec 2008 15:21:46 -0500 Subject: NFSv4: Clean up the support for returning multiple delegations Add a flag to mark delegations as requiring return, then run a garbage collector. In the future, this will allow for more flexible delegation management, where delegations may be marked for return if it turns out that they are not being referenced. Signed-off-by: Trond Myklebust --- fs/nfs/delegation.c | 97 +++++++++++++++++++++++++---------------------------- 1 file changed, 45 insertions(+), 52 deletions(-) (limited to 'fs/nfs/delegation.c') diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index ebc06f2da31..bc9d4f9a788 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -255,6 +255,34 @@ static int __nfs_inode_return_delegation(struct inode *inode, struct nfs_delegat return nfs_do_return_delegation(inode, delegation, 1); } +/* + * Return all delegations that have been marked for return + */ +static void nfs_client_return_marked_delegations(struct nfs_client *clp) +{ + struct nfs_delegation *delegation; + struct inode *inode; + +restart: + rcu_read_lock(); + list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) { + if (!test_and_clear_bit(NFS_DELEGATION_RETURN, &delegation->flags)) + continue; + inode = nfs_delegation_grab_inode(delegation); + if (inode == NULL) + continue; + spin_lock(&clp->cl_lock); + delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL); + spin_unlock(&clp->cl_lock); + rcu_read_unlock(); + if (delegation != NULL) + __nfs_inode_return_delegation(inode, delegation); + iput(inode); + goto restart; + } + rcu_read_unlock(); +} + /* * This function returns the delegation without reclaiming opens * or protecting against delegation reclaims. @@ -296,63 +324,46 @@ int nfs_inode_return_delegation(struct inode *inode) /* * Return all delegations associated to a super block */ -void nfs_return_all_delegations(struct super_block *sb) +void nfs_super_return_all_delegations(struct super_block *sb) { struct nfs_client *clp = NFS_SB(sb)->nfs_client; struct nfs_delegation *delegation; - struct inode *inode; if (clp == NULL) return; -restart: rcu_read_lock(); list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) { - inode = NULL; spin_lock(&delegation->lock); if (delegation->inode != NULL && delegation->inode->i_sb == sb) - inode = igrab(delegation->inode); + set_bit(NFS_DELEGATION_RETURN, &delegation->flags); spin_unlock(&delegation->lock); - if (inode == NULL) - continue; - spin_lock(&clp->cl_lock); - delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL); - spin_unlock(&clp->cl_lock); - rcu_read_unlock(); - if (delegation != NULL) - __nfs_inode_return_delegation(inode, delegation); - iput(inode); - goto restart; } rcu_read_unlock(); + nfs_client_return_marked_delegations(clp); +} + +static void nfs_client_return_all_delegations(struct nfs_client *clp) +{ + struct nfs_delegation *delegation; + + rcu_read_lock(); + list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) + set_bit(NFS_DELEGATION_RETURN, &delegation->flags); + rcu_read_unlock(); + nfs_client_return_marked_delegations(clp); } static int nfs_do_expire_all_delegations(void *ptr) { struct nfs_client *clp = ptr; - struct nfs_delegation *delegation; - struct inode *inode; allow_signal(SIGKILL); -restart: + if (test_bit(NFS4CLNT_STATE_RECOVER, &clp->cl_state) != 0) goto out; if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) goto out; - rcu_read_lock(); - list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) { - inode = nfs_delegation_grab_inode(delegation); - if (inode == NULL) - continue; - spin_lock(&clp->cl_lock); - delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL); - spin_unlock(&clp->cl_lock); - rcu_read_unlock(); - if (delegation) - __nfs_inode_return_delegation(inode, delegation); - iput(inode); - goto restart; - } - rcu_read_unlock(); + nfs_client_return_all_delegations(clp); out: nfs_put_client(clp); module_put_and_exit(0); @@ -379,27 +390,9 @@ void nfs_expire_all_delegations(struct nfs_client *clp) */ void nfs_handle_cb_pathdown(struct nfs_client *clp) { - struct nfs_delegation *delegation; - struct inode *inode; - if (clp == NULL) return; -restart: - rcu_read_lock(); - list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) { - inode = nfs_delegation_grab_inode(delegation); - if (inode == NULL) - continue; - spin_lock(&clp->cl_lock); - delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL); - spin_unlock(&clp->cl_lock); - rcu_read_unlock(); - if (delegation != NULL) - __nfs_inode_return_delegation(inode, delegation); - iput(inode); - goto restart; - } - rcu_read_unlock(); + nfs_client_return_all_delegations(clp); } struct recall_threadargs { -- cgit v1.2.3