NFS: Move cl_delegations to the nfs_server struct
Delegations are per-inode, not per-nfs_client. When a server file
system is migrated, delegations on the client must be moved from the
source to the destination nfs_server. Make it easier to manage a
mount point's delegation list across a migration event by moving the
list to the nfs_server struct.
Clean up: I added documenting comments to public functions I changed
in this patch. For consistency I added comments to all the other
public functions in fs/nfs/delegation.c.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index 521d71b..364e432 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -40,11 +40,23 @@
call_rcu(&delegation->rcu, nfs_free_delegation_callback);
}
+/**
+ * nfs_mark_delegation_referenced - set delegation's REFERENCED flag
+ * @delegation: delegation to process
+ *
+ */
void nfs_mark_delegation_referenced(struct nfs_delegation *delegation)
{
set_bit(NFS_DELEGATION_REFERENCED, &delegation->flags);
}
+/**
+ * nfs_have_delegation - check if inode has a delegation
+ * @inode: inode to check
+ * @flags: delegation types to check for
+ *
+ * Returns one if inode has the indicated delegation, otherwise zero.
+ */
int nfs_have_delegation(struct inode *inode, fmode_t flags)
{
struct nfs_delegation *delegation;
@@ -119,10 +131,15 @@
return 0;
}
-/*
- * Set up a delegation on an inode
+/**
+ * nfs_inode_reclaim_delegation - process a delegation reclaim request
+ * @inode: inode to process
+ * @cred: credential to use for request
+ * @res: new delegation state from server
+ *
*/
-void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res)
+void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred,
+ struct nfs_openres *res)
{
struct nfs_delegation *delegation;
struct rpc_cred *oldcred = NULL;
@@ -177,11 +194,11 @@
static struct nfs_delegation *
nfs_detach_delegation_locked(struct nfs_inode *nfsi,
- struct nfs_client *clp)
+ struct nfs_server *server)
{
struct nfs_delegation *delegation =
rcu_dereference_protected(nfsi->delegation,
- lockdep_is_held(&clp->cl_lock));
+ lockdep_is_held(&server->nfs_client->cl_lock));
if (delegation == NULL)
goto nomatch;
@@ -198,22 +215,29 @@
}
static struct nfs_delegation *nfs_detach_delegation(struct nfs_inode *nfsi,
- struct nfs_client *clp)
+ struct nfs_server *server)
{
+ struct nfs_client *clp = server->nfs_client;
struct nfs_delegation *delegation;
spin_lock(&clp->cl_lock);
- delegation = nfs_detach_delegation_locked(nfsi, clp);
+ delegation = nfs_detach_delegation_locked(nfsi, server);
spin_unlock(&clp->cl_lock);
return delegation;
}
-/*
- * Set up a delegation on an inode
+/**
+ * nfs_inode_set_delegation - set up a delegation on an inode
+ * @inode: inode to which delegation applies
+ * @cred: cred to use for subsequent delegation processing
+ * @res: new delegation state from server
+ *
+ * Returns zero on success, or a negative errno value.
*/
int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res)
{
- struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+ struct nfs_server *server = NFS_SERVER(inode);
+ struct nfs_client *clp = server->nfs_client;
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_delegation *delegation, *old_delegation;
struct nfs_delegation *freeme = NULL;
@@ -234,7 +258,7 @@
spin_lock(&clp->cl_lock);
old_delegation = rcu_dereference_protected(nfsi->delegation,
- lockdep_is_held(&clp->cl_lock));
+ lockdep_is_held(&clp->cl_lock));
if (old_delegation != NULL) {
if (memcmp(&delegation->stateid, &old_delegation->stateid,
sizeof(old_delegation->stateid)) == 0 &&
@@ -253,9 +277,9 @@
delegation = NULL;
goto out;
}
- freeme = nfs_detach_delegation_locked(nfsi, clp);
+ freeme = nfs_detach_delegation_locked(nfsi, server);
}
- list_add_rcu(&delegation->super_list, &clp->cl_delegations);
+ list_add_rcu(&delegation->super_list, &server->delegations);
nfsi->delegation_state = delegation->type;
rcu_assign_pointer(nfsi->delegation, delegation);
delegation = NULL;
@@ -297,67 +321,85 @@
return err;
}
-/*
- * Return all delegations that have been marked for return
+/**
+ * nfs_client_return_marked_delegations - return previously marked delegations
+ * @clp: nfs_client to process
+ *
+ * Returns zero on success, or a negative errno value.
*/
int nfs_client_return_marked_delegations(struct nfs_client *clp)
{
struct nfs_delegation *delegation;
+ struct nfs_server *server;
struct inode *inode;
int err = 0;
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;
- delegation = nfs_detach_delegation(NFS_I(inode), clp);
- rcu_read_unlock();
- if (delegation != NULL) {
- filemap_flush(inode->i_mapping);
- err = __nfs_inode_return_delegation(inode, delegation, 0);
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ list_for_each_entry_rcu(delegation, &server->delegations,
+ super_list) {
+ if (!test_and_clear_bit(NFS_DELEGATION_RETURN,
+ &delegation->flags))
+ continue;
+ inode = nfs_delegation_grab_inode(delegation);
+ if (inode == NULL)
+ continue;
+ delegation = nfs_detach_delegation(NFS_I(inode),
+ server);
+ rcu_read_unlock();
+
+ if (delegation != NULL) {
+ filemap_flush(inode->i_mapping);
+ err = __nfs_inode_return_delegation(inode,
+ delegation, 0);
+ }
+ iput(inode);
+ if (!err)
+ goto restart;
+ set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
+ return err;
}
- iput(inode);
- if (!err)
- goto restart;
- set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
- return err;
}
rcu_read_unlock();
return 0;
}
-/*
- * This function returns the delegation without reclaiming opens
- * or protecting against delegation reclaims.
- * It is therefore really only safe to be called from
- * nfs4_clear_inode()
+/**
+ * nfs_inode_return_delegation_noreclaim - return delegation, don't reclaim opens
+ * @inode: inode to process
+ *
+ * Does not protect against delegation reclaims, therefore really only safe
+ * to be called from nfs4_clear_inode().
*/
void nfs_inode_return_delegation_noreclaim(struct inode *inode)
{
- struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+ struct nfs_server *server = NFS_SERVER(inode);
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_delegation *delegation;
if (rcu_access_pointer(nfsi->delegation) != NULL) {
- delegation = nfs_detach_delegation(nfsi, clp);
+ delegation = nfs_detach_delegation(nfsi, server);
if (delegation != NULL)
nfs_do_return_delegation(inode, delegation, 0);
}
}
+/**
+ * nfs_inode_return_delegation - synchronously return a delegation
+ * @inode: inode to process
+ *
+ * Returns zero on success, or a negative errno value.
+ */
int nfs_inode_return_delegation(struct inode *inode)
{
- struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+ struct nfs_server *server = NFS_SERVER(inode);
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_delegation *delegation;
int err = 0;
if (rcu_access_pointer(nfsi->delegation) != NULL) {
- delegation = nfs_detach_delegation(nfsi, clp);
+ delegation = nfs_detach_delegation(nfsi, server);
if (delegation != NULL) {
nfs_wb_all(inode);
err = __nfs_inode_return_delegation(inode, delegation, 1);
@@ -366,46 +408,61 @@
return err;
}
-static void nfs_mark_return_delegation(struct nfs_client *clp, struct nfs_delegation *delegation)
+static void nfs_mark_return_delegation(struct nfs_delegation *delegation)
{
+ struct nfs_client *clp = NFS_SERVER(delegation->inode)->nfs_client;
+
set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
}
-/*
- * Return all delegations associated to a super block
+/**
+ * nfs_super_return_all_delegations - return delegations for one superblock
+ * @sb: sb to process
+ *
*/
void nfs_super_return_all_delegations(struct super_block *sb)
{
- struct nfs_client *clp = NFS_SB(sb)->nfs_client;
+ struct nfs_server *server = NFS_SB(sb);
+ struct nfs_client *clp = server->nfs_client;
struct nfs_delegation *delegation;
if (clp == NULL)
return;
+
rcu_read_lock();
- list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
spin_lock(&delegation->lock);
- if (delegation->inode != NULL && delegation->inode->i_sb == sb)
- set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
+ set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
spin_unlock(&delegation->lock);
}
rcu_read_unlock();
+
if (nfs_client_return_marked_delegations(clp) != 0)
nfs4_schedule_state_manager(clp);
}
-static
-void nfs_client_mark_return_all_delegation_types(struct nfs_client *clp, fmode_t flags)
+static void nfs_mark_return_all_delegation_types(struct nfs_server *server,
+ fmode_t flags)
{
struct nfs_delegation *delegation;
- rcu_read_lock();
- list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
if ((delegation->type == (FMODE_READ|FMODE_WRITE)) && !(flags & FMODE_WRITE))
continue;
if (delegation->type & flags)
- nfs_mark_return_delegation(clp, delegation);
+ nfs_mark_return_delegation(delegation);
}
+}
+
+static void nfs_client_mark_return_all_delegation_types(struct nfs_client *clp,
+ fmode_t flags)
+{
+ struct nfs_server *server;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+ nfs_mark_return_all_delegation_types(server, flags);
rcu_read_unlock();
}
@@ -420,19 +477,32 @@
nfs4_schedule_state_manager(clp);
}
+/**
+ * nfs_expire_all_delegation_types
+ * @clp: client to process
+ * @flags: delegation types to expire
+ *
+ */
void nfs_expire_all_delegation_types(struct nfs_client *clp, fmode_t flags)
{
nfs_client_mark_return_all_delegation_types(clp, flags);
nfs_delegation_run_state_manager(clp);
}
+/**
+ * nfs_expire_all_delegations
+ * @clp: client to process
+ *
+ */
void nfs_expire_all_delegations(struct nfs_client *clp)
{
nfs_expire_all_delegation_types(clp, FMODE_READ|FMODE_WRITE);
}
-/*
- * Return all delegations following an NFS4ERR_CB_PATH_DOWN error.
+/**
+ * nfs_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
+ * @clp: client to process
+ *
*/
void nfs_handle_cb_pathdown(struct nfs_client *clp)
{
@@ -441,29 +511,43 @@
nfs_client_mark_return_all_delegations(clp);
}
-static void nfs_client_mark_return_unreferenced_delegations(struct nfs_client *clp)
+static void nfs_mark_return_unreferenced_delegations(struct nfs_server *server)
{
struct nfs_delegation *delegation;
- rcu_read_lock();
- list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
if (test_and_clear_bit(NFS_DELEGATION_REFERENCED, &delegation->flags))
continue;
- nfs_mark_return_delegation(clp, delegation);
+ nfs_mark_return_delegation(delegation);
}
- rcu_read_unlock();
}
+/**
+ * nfs_expire_unreferenced_delegations - Eliminate unused delegations
+ * @clp: nfs_client to process
+ *
+ */
void nfs_expire_unreferenced_delegations(struct nfs_client *clp)
{
- nfs_client_mark_return_unreferenced_delegations(clp);
+ struct nfs_server *server;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+ nfs_mark_return_unreferenced_delegations(server);
+ rcu_read_unlock();
+
nfs_delegation_run_state_manager(clp);
}
-/*
- * Asynchronous delegation recall!
+/**
+ * nfs_async_inode_return_delegation - asynchronously return a delegation
+ * @inode: inode to process
+ * @stateid: state ID information from CB_RECALL arguments
+ *
+ * Returns zero on success, or a negative errno value.
*/
-int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *stateid)
+int nfs_async_inode_return_delegation(struct inode *inode,
+ const nfs4_stateid *stateid)
{
struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
struct nfs_delegation *delegation;
@@ -475,22 +559,21 @@
rcu_read_unlock();
return -ENOENT;
}
-
- nfs_mark_return_delegation(clp, delegation);
+ nfs_mark_return_delegation(delegation);
rcu_read_unlock();
+
nfs_delegation_run_state_manager(clp);
return 0;
}
-/*
- * Retrieve the inode associated with a delegation
- */
-struct inode *nfs_delegation_find_inode(struct nfs_client *clp, const struct nfs_fh *fhandle)
+static struct inode *
+nfs_delegation_find_inode_server(struct nfs_server *server,
+ const struct nfs_fh *fhandle)
{
struct nfs_delegation *delegation;
struct inode *res = NULL;
- rcu_read_lock();
- list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
+
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
spin_lock(&delegation->lock);
if (delegation->inode != NULL &&
nfs_compare_fh(fhandle, &NFS_I(delegation->inode)->fh) == 0) {
@@ -500,47 +583,121 @@
if (res != NULL)
break;
}
+ return res;
+}
+
+/**
+ * nfs_delegation_find_inode - retrieve the inode associated with a delegation
+ * @clp: client state handle
+ * @fhandle: filehandle from a delegation recall
+ *
+ * Returns pointer to inode matching "fhandle," or NULL if a matching inode
+ * cannot be found.
+ */
+struct inode *nfs_delegation_find_inode(struct nfs_client *clp,
+ const struct nfs_fh *fhandle)
+{
+ struct nfs_server *server;
+ struct inode *res = NULL;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ res = nfs_delegation_find_inode_server(server, fhandle);
+ if (res != NULL)
+ break;
+ }
rcu_read_unlock();
return res;
}
-/*
- * Mark all delegations as needing to be reclaimed
+static void nfs_delegation_mark_reclaim_server(struct nfs_server *server)
+{
+ struct nfs_delegation *delegation;
+
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list)
+ set_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
+}
+
+/**
+ * nfs_delegation_mark_reclaim - mark all delegations as needing to be reclaimed
+ * @clp: nfs_client to process
+ *
*/
void nfs_delegation_mark_reclaim(struct nfs_client *clp)
{
- struct nfs_delegation *delegation;
+ struct nfs_server *server;
+
rcu_read_lock();
- list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list)
- set_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+ nfs_delegation_mark_reclaim_server(server);
rcu_read_unlock();
}
-/*
- * Reap all unclaimed delegations after reboot recovery is done
+/**
+ * nfs_delegation_reap_unclaimed - reap unclaimed delegations after reboot recovery is done
+ * @clp: nfs_client to process
+ *
*/
void nfs_delegation_reap_unclaimed(struct nfs_client *clp)
{
struct nfs_delegation *delegation;
+ struct nfs_server *server;
struct inode *inode;
+
restart:
rcu_read_lock();
- list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
- if (test_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags) == 0)
- continue;
- inode = nfs_delegation_grab_inode(delegation);
- if (inode == NULL)
- continue;
- delegation = nfs_detach_delegation(NFS_I(inode), clp);
- rcu_read_unlock();
- if (delegation != NULL)
- nfs_free_delegation(delegation);
- iput(inode);
- goto restart;
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ list_for_each_entry_rcu(delegation, &server->delegations,
+ super_list) {
+ if (test_bit(NFS_DELEGATION_NEED_RECLAIM,
+ &delegation->flags) == 0)
+ continue;
+ inode = nfs_delegation_grab_inode(delegation);
+ if (inode == NULL)
+ continue;
+ delegation = nfs_detach_delegation(NFS_I(inode),
+ server);
+ rcu_read_unlock();
+
+ if (delegation != NULL)
+ nfs_free_delegation(delegation);
+ iput(inode);
+ goto restart;
+ }
}
rcu_read_unlock();
}
+/**
+ * nfs_delegations_present - check for existence of delegations
+ * @clp: client state handle
+ *
+ * Returns one if there are any nfs_delegation structures attached
+ * to this nfs_client.
+ */
+int nfs_delegations_present(struct nfs_client *clp)
+{
+ struct nfs_server *server;
+ int ret = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+ if (!list_empty(&server->delegations)) {
+ ret = 1;
+ break;
+ }
+ rcu_read_unlock();
+ return ret;
+}
+
+/**
+ * nfs4_copy_delegation_stateid - Copy inode's state ID information
+ * @dst: stateid data structure to fill in
+ * @inode: inode to check
+ *
+ * Returns one and fills in "dst->data" * if inode had a delegation,
+ * otherwise zero is returned.
+ */
int nfs4_copy_delegation_stateid(nfs4_stateid *dst, struct inode *inode)
{
struct nfs_inode *nfsi = NFS_I(inode);