2010-12-24 01:32:26

by Chuck Lever

[permalink] [raw]
Subject: [PATCH 0/4] Refactor data structures to support NFSv4 migration (2)

Trond-

Here are four patches that move fields related to NFSv4 state from the
nfs_client struct to the nfs_server struct. This change facilitates
the eventual implementation of NFSv4 migration.

This series passes simple tests: Full Cthon suite passes over NFSv4
against an OpenSolaris 2009.6 NFS server, and a full "allmodconfig"
-j3 kernel build completes on NFSv4 without hangs or lockdep splats
on a two-way client.

Since the first series:

. Make the new server->delegations unconditionally compiled in
. In fs/nfs/nfs4state.c, where possible, take cl_lock after invoking
rcu_read_lock() instead of before invoking it

---

Chuck Lever (4):
NFS: Move cl_delegations to the nfs_server struct
NFS: Introduce nfs_detach_delegations()
NFS: Move cl_state_owners and related fields to the nfs_server struct
NFS: Allow walking nfs_client.cl_superblocks list outside client.c


fs/nfs/client.c | 46 +++---
fs/nfs/delegation.c | 362 ++++++++++++++++++++++++++++++++-------------
fs/nfs/delegation.h | 1
fs/nfs/nfs4_fs.h | 2
fs/nfs/nfs4renewd.c | 11 +
fs/nfs/nfs4state.c | 251 ++++++++++++++++++++++---------
include/linux/nfs_fs_sb.h | 11 +
7 files changed, 481 insertions(+), 203 deletions(-)

--
Chuck Lever


2010-12-24 01:32:47

by Chuck Lever

[permalink] [raw]
Subject: [PATCH 2/4] NFS: Move cl_state_owners and related fields to the nfs_server struct

NFSv4 migration needs to reassociate state owners from the source to
the destination nfs_server data structures. To make that easier, move
the cl_state_owners field to the nfs_server struct. cl_openowner_id
and cl_lockowner_id accompany this move, as they are used in
conjunction with cl_state_owners.

The cl_lock field in the parent nfs_client continues to protect all
three of these fields.

Signed-off-by: Chuck Lever <[email protected]>
---

fs/nfs/nfs4_fs.h | 2
fs/nfs/nfs4state.c | 251 ++++++++++++++++++++++++++++++++-------------
include/linux/nfs_fs_sb.h | 9 +-
3 files changed, 186 insertions(+), 76 deletions(-)

diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 7a6eecf..fa5c5d3 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -109,7 +109,7 @@ struct nfs_unique_id {
struct nfs4_state_owner {
struct nfs_unique_id so_owner_id;
struct nfs_server *so_server;
- struct rb_node so_client_node;
+ struct rb_node so_server_node;

struct rpc_cred *so_cred; /* Associated cred */

diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index f575a31..d863723 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -105,14 +105,17 @@ static void nfs4_clear_machine_cred(struct nfs_client *clp)
put_rpccred(cred);
}

-struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
+static struct rpc_cred *
+nfs4_get_renew_cred_server_locked(struct nfs_server *server)
{
+ struct rpc_cred *cred = NULL;
struct nfs4_state_owner *sp;
struct rb_node *pos;
- struct rpc_cred *cred = NULL;

- for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
- sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
+ for (pos = rb_first(&server->state_owners);
+ pos != NULL;
+ pos = rb_next(pos)) {
+ sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
if (list_empty(&sp->so_states))
continue;
cred = get_rpccred(sp->so_cred);
@@ -121,6 +124,28 @@ struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
return cred;
}

+/**
+ * nfs4_get_renew_cred_locked - Acquire credential for a renew operation
+ * @clp: client state handle
+ *
+ * Returns an rpc_cred with reference count bumped, or NULL.
+ * Caller must hold clp->cl_lock.
+ */
+struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
+{
+ struct rpc_cred *cred = NULL;
+ struct nfs_server *server;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ cred = nfs4_get_renew_cred_server_locked(server);
+ if (cred != NULL)
+ break;
+ }
+ rcu_read_unlock();
+ return cred;
+}
+
#if defined(CONFIG_NFS_V4_1)

static int nfs41_setup_state_renewal(struct nfs_client *clp)
@@ -210,28 +235,56 @@ struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)

#endif /* CONFIG_NFS_V4_1 */

-struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
+static struct rpc_cred *
+nfs4_get_setclientid_cred_server(struct nfs_server *server)
{
+ struct nfs_client *clp = server->nfs_client;
+ struct rpc_cred *cred = NULL;
struct nfs4_state_owner *sp;
struct rb_node *pos;
+
+ spin_lock(&clp->cl_lock);
+ pos = rb_first(&server->state_owners);
+ if (pos != NULL) {
+ sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
+ cred = get_rpccred(sp->so_cred);
+ }
+ spin_unlock(&clp->cl_lock);
+ return cred;
+}
+
+/**
+ * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
+ * @clp: client state handle
+ *
+ * Returns an rpc_cred with reference count bumped, or NULL.
+ */
+struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
+{
+ struct nfs_server *server;
struct rpc_cred *cred;

spin_lock(&clp->cl_lock);
cred = nfs4_get_machine_cred_locked(clp);
+ spin_unlock(&clp->cl_lock);
if (cred != NULL)
goto out;
- pos = rb_first(&clp->cl_state_owners);
- if (pos != NULL) {
- sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
- cred = get_rpccred(sp->so_cred);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ cred = nfs4_get_setclientid_cred_server(server);
+ if (cred != NULL)
+ break;
}
+ rcu_read_unlock();
+
out:
- spin_unlock(&clp->cl_lock);
return cred;
}

-static void nfs_alloc_unique_id(struct rb_root *root, struct nfs_unique_id *new,
- __u64 minval, int maxbits)
+static void nfs_alloc_unique_id_locked(struct rb_root *root,
+ struct nfs_unique_id *new,
+ __u64 minval, int maxbits)
{
struct rb_node **p, *parent;
struct nfs_unique_id *pos;
@@ -286,16 +339,15 @@ static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id)
}

static struct nfs4_state_owner *
-nfs4_find_state_owner(struct nfs_server *server, struct rpc_cred *cred)
+nfs4_find_state_owner_locked(struct nfs_server *server, struct rpc_cred *cred)
{
- struct nfs_client *clp = server->nfs_client;
- struct rb_node **p = &clp->cl_state_owners.rb_node,
+ struct rb_node **p = &server->state_owners.rb_node,
*parent = NULL;
struct nfs4_state_owner *sp, *res = NULL;

while (*p != NULL) {
parent = *p;
- sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
+ sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);

if (server < sp->so_server) {
p = &parent->rb_left;
@@ -319,24 +371,17 @@ nfs4_find_state_owner(struct nfs_server *server, struct rpc_cred *cred)
}

static struct nfs4_state_owner *
-nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new)
+nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
{
- struct rb_node **p = &clp->cl_state_owners.rb_node,
+ struct nfs_server *server = new->so_server;
+ struct rb_node **p = &server->state_owners.rb_node,
*parent = NULL;
struct nfs4_state_owner *sp;

while (*p != NULL) {
parent = *p;
- sp = rb_entry(parent, struct nfs4_state_owner, so_client_node);
+ sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);

- if (new->so_server < sp->so_server) {
- p = &parent->rb_left;
- continue;
- }
- if (new->so_server > sp->so_server) {
- p = &parent->rb_right;
- continue;
- }
if (new->so_cred < sp->so_cred)
p = &parent->rb_left;
else if (new->so_cred > sp->so_cred)
@@ -346,18 +391,21 @@ nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new)
return sp;
}
}
- nfs_alloc_unique_id(&clp->cl_openowner_id, &new->so_owner_id, 1, 64);
- rb_link_node(&new->so_client_node, parent, p);
- rb_insert_color(&new->so_client_node, &clp->cl_state_owners);
+ nfs_alloc_unique_id_locked(&server->openowner_id,
+ &new->so_owner_id, 1, 64);
+ rb_link_node(&new->so_server_node, parent, p);
+ rb_insert_color(&new->so_server_node, &server->state_owners);
return new;
}

static void
-nfs4_remove_state_owner(struct nfs_client *clp, struct nfs4_state_owner *sp)
+nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
{
- if (!RB_EMPTY_NODE(&sp->so_client_node))
- rb_erase(&sp->so_client_node, &clp->cl_state_owners);
- nfs_free_unique_id(&clp->cl_openowner_id, &sp->so_owner_id);
+ struct nfs_server *server = sp->so_server;
+
+ if (!RB_EMPTY_NODE(&sp->so_server_node))
+ rb_erase(&sp->so_server_node, &server->state_owners);
+ nfs_free_unique_id(&server->openowner_id, &sp->so_owner_id);
}

/*
@@ -386,23 +434,32 @@ nfs4_alloc_state_owner(void)
static void
nfs4_drop_state_owner(struct nfs4_state_owner *sp)
{
- if (!RB_EMPTY_NODE(&sp->so_client_node)) {
- struct nfs_client *clp = sp->so_server->nfs_client;
+ if (!RB_EMPTY_NODE(&sp->so_server_node)) {
+ struct nfs_server *server = sp->so_server;
+ struct nfs_client *clp = server->nfs_client;

spin_lock(&clp->cl_lock);
- rb_erase(&sp->so_client_node, &clp->cl_state_owners);
- RB_CLEAR_NODE(&sp->so_client_node);
+ rb_erase(&sp->so_server_node, &server->state_owners);
+ RB_CLEAR_NODE(&sp->so_server_node);
spin_unlock(&clp->cl_lock);
}
}

-struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
+/**
+ * nfs4_get_state_owner - Look up a state owner given a credential
+ * @server: nfs_server to search
+ * @cred: RPC credential to match
+ *
+ * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
+ */
+struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
+ struct rpc_cred *cred)
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp, *new;

spin_lock(&clp->cl_lock);
- sp = nfs4_find_state_owner(server, cred);
+ sp = nfs4_find_state_owner_locked(server, cred);
spin_unlock(&clp->cl_lock);
if (sp != NULL)
return sp;
@@ -412,7 +469,7 @@ struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct
new->so_server = server;
new->so_cred = cred;
spin_lock(&clp->cl_lock);
- sp = nfs4_insert_state_owner(clp, new);
+ sp = nfs4_insert_state_owner_locked(new);
spin_unlock(&clp->cl_lock);
if (sp == new)
get_rpccred(cred);
@@ -423,6 +480,11 @@ struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct
return sp;
}

+/**
+ * nfs4_put_state_owner - Release a nfs4_state_owner
+ * @sp: state owner data to release
+ *
+ */
void nfs4_put_state_owner(struct nfs4_state_owner *sp)
{
struct nfs_client *clp = sp->so_server->nfs_client;
@@ -430,7 +492,7 @@ void nfs4_put_state_owner(struct nfs4_state_owner *sp)

if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
return;
- nfs4_remove_state_owner(clp, sp);
+ nfs4_remove_state_owner_locked(sp);
spin_unlock(&clp->cl_lock);
rpc_destroy_wait_queue(&sp->so_sequence.wait);
put_rpccred(cred);
@@ -633,7 +695,8 @@ __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_p
static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner, pid_t fl_pid, unsigned int type)
{
struct nfs4_lock_state *lsp;
- struct nfs_client *clp = state->owner->so_server->nfs_client;
+ struct nfs_server *server = state->owner->so_server;
+ struct nfs_client *clp = server->nfs_client;

lsp = kzalloc(sizeof(*lsp), GFP_NOFS);
if (lsp == NULL)
@@ -657,7 +720,7 @@ static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, f
return NULL;
}
spin_lock(&clp->cl_lock);
- nfs_alloc_unique_id(&clp->cl_lockowner_id, &lsp->ls_id, 1, 64);
+ nfs_alloc_unique_id_locked(&server->lockowner_id, &lsp->ls_id, 1, 64);
spin_unlock(&clp->cl_lock);
INIT_LIST_HEAD(&lsp->ls_locks);
return lsp;
@@ -665,10 +728,11 @@ static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, f

static void nfs4_free_lock_state(struct nfs4_lock_state *lsp)
{
- struct nfs_client *clp = lsp->ls_state->owner->so_server->nfs_client;
+ struct nfs_server *server = lsp->ls_state->owner->so_server;
+ struct nfs_client *clp = server->nfs_client;

spin_lock(&clp->cl_lock);
- nfs_free_unique_id(&clp->cl_lockowner_id, &lsp->ls_id);
+ nfs_free_unique_id(&server->lockowner_id, &lsp->ls_id);
spin_unlock(&clp->cl_lock);
rpc_destroy_wait_queue(&lsp->ls_sequence.wait);
kfree(lsp);
@@ -1114,15 +1178,19 @@ static void nfs4_clear_open_state(struct nfs4_state *state)
}
}

-static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp, int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
+static void nfs4_reset_seqids(struct nfs_server *server,
+ int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
{
+ struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp;
struct rb_node *pos;
struct nfs4_state *state;

- /* Reset all sequence ids to zero */
- for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
- sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
+ spin_lock(&clp->cl_lock);
+ for (pos = rb_first(&server->state_owners);
+ pos != NULL;
+ pos = rb_next(pos)) {
+ sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
sp->so_seqid.flags = 0;
spin_lock(&sp->so_lock);
list_for_each_entry(state, &sp->so_states, open_states) {
@@ -1131,6 +1199,18 @@ static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp, int (*mark_re
}
spin_unlock(&sp->so_lock);
}
+ spin_unlock(&clp->cl_lock);
+}
+
+static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
+ int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
+{
+ struct nfs_server *server;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+ nfs4_reset_seqids(server, mark_reclaim);
+ rcu_read_unlock();
}

static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
@@ -1148,25 +1228,41 @@ static void nfs4_reclaim_complete(struct nfs_client *clp,
(void)ops->reclaim_complete(clp);
}

-static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
+static void nfs4_clear_reclaim_server(struct nfs_server *server)
{
+ struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp;
struct rb_node *pos;
struct nfs4_state *state;

- if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
- return 0;
-
- for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
- sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
+ spin_lock(&clp->cl_lock);
+ for (pos = rb_first(&server->state_owners);
+ pos != NULL;
+ pos = rb_next(pos)) {
+ sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
spin_lock(&sp->so_lock);
list_for_each_entry(state, &sp->so_states, open_states) {
- if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags))
+ if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
+ &state->flags))
continue;
nfs4_state_mark_reclaim_nograce(clp, state);
}
spin_unlock(&sp->so_lock);
}
+ spin_unlock(&clp->cl_lock);
+}
+
+static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
+{
+ struct nfs_server *server;
+
+ if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
+ return 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+ nfs4_clear_reclaim_server(server);
+ rcu_read_unlock();

nfs_delegation_reap_unclaimed(clp);
return 1;
@@ -1238,27 +1334,40 @@ static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)

static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
{
+ struct nfs4_state_owner *sp;
+ struct nfs_server *server;
struct rb_node *pos;
int status = 0;

restart:
- spin_lock(&clp->cl_lock);
- for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
- struct nfs4_state_owner *sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
- if (!test_and_clear_bit(ops->owner_flag_bit, &sp->so_flags))
- continue;
- atomic_inc(&sp->so_count);
- spin_unlock(&clp->cl_lock);
- status = nfs4_reclaim_open_state(sp, ops);
- if (status < 0) {
- set_bit(ops->owner_flag_bit, &sp->so_flags);
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ spin_lock(&clp->cl_lock);
+ for (pos = rb_first(&server->state_owners);
+ pos != NULL;
+ pos = rb_next(pos)) {
+ sp = rb_entry(pos,
+ struct nfs4_state_owner, so_server_node);
+ if (!test_and_clear_bit(ops->owner_flag_bit,
+ &sp->so_flags))
+ continue;
+ atomic_inc(&sp->so_count);
+ spin_unlock(&clp->cl_lock);
+ rcu_read_unlock();
+
+ status = nfs4_reclaim_open_state(sp, ops);
+ if (status < 0) {
+ set_bit(ops->owner_flag_bit, &sp->so_flags);
+ nfs4_put_state_owner(sp);
+ return nfs4_recovery_handle_error(clp, status);
+ }
+
nfs4_put_state_owner(sp);
- return nfs4_recovery_handle_error(clp, status);
+ goto restart;
}
- nfs4_put_state_owner(sp);
- goto restart;
+ spin_unlock(&clp->cl_lock);
}
- spin_unlock(&clp->cl_lock);
+ rcu_read_unlock();
return status;
}

diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 452d964..e96ec55 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -47,11 +47,7 @@ struct nfs_client {
u64 cl_clientid; /* constant */
unsigned long cl_state;

- struct rb_root cl_openowner_id;
- struct rb_root cl_lockowner_id;
-
struct list_head cl_delegations;
- struct rb_root cl_state_owners;
spinlock_t cl_lock;

unsigned long cl_lease_time;
@@ -148,6 +144,11 @@ struct nfs_server {
that are supported on this
filesystem */
struct pnfs_layoutdriver_type *pnfs_curr_ld; /* Active layout driver */
+
+ /* the following fields are protected by nfs_client->cl_lock */
+ struct rb_root state_owners;
+ struct rb_root openowner_id;
+ struct rb_root lockowner_id;
#endif
void (*destroy)(struct nfs_server *);



2010-12-24 01:32:36

by Chuck Lever

[permalink] [raw]
Subject: [PATCH 1/4] NFS: Allow walking nfs_client.cl_superblocks list outside client.c

We're about to move some fields from struct nfs_client to struct
nfs_server. There is a many-to-one relationship between nfs_servers
and nfs_clients. After these fields are moved to the nfs_server
struct, to visit all of the data in these fields that is owned by one
nfs_client, code will need to visit each nfs_server on the
cl_superblocks list for that nfs_client.

To serialize changes to the cl_superblocks list during these little
expeditions, protect the list with RCU.

Signed-off-by: Chuck Lever <[email protected]>
---

fs/nfs/client.c | 44 +++++++++++++++++++++++++-------------------
fs/nfs/nfs4renewd.c | 9 +++++++--
2 files changed, 32 insertions(+), 21 deletions(-)

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 0870d0d..05e2ee2 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -988,6 +988,27 @@ static void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_serve
target->options = source->options;
}

+static void nfs_server_insert_lists(struct nfs_server *server)
+{
+ struct nfs_client *clp = server->nfs_client;
+
+ spin_lock(&nfs_client_lock);
+ list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
+ list_add_tail(&server->master_link, &nfs_volume_list);
+ spin_unlock(&nfs_client_lock);
+
+}
+
+static void nfs_server_remove_lists(struct nfs_server *server)
+{
+ spin_lock(&nfs_client_lock);
+ list_del_rcu(&server->client_link);
+ list_del(&server->master_link);
+ spin_unlock(&nfs_client_lock);
+
+ synchronize_rcu();
+}
+
/*
* Allocate and initialise a server record
*/
@@ -1029,11 +1050,8 @@ void nfs_free_server(struct nfs_server *server)
{
dprintk("--> nfs_free_server()\n");

+ nfs_server_remove_lists(server);
unset_pnfs_layoutdriver(server);
- spin_lock(&nfs_client_lock);
- list_del(&server->client_link);
- list_del(&server->master_link);
- spin_unlock(&nfs_client_lock);

if (server->destroy != NULL)
server->destroy(server);
@@ -1108,11 +1126,7 @@ struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
(unsigned long long) server->fsid.major,
(unsigned long long) server->fsid.minor);

- spin_lock(&nfs_client_lock);
- list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
- list_add_tail(&server->master_link, &nfs_volume_list);
- spin_unlock(&nfs_client_lock);
-
+ nfs_server_insert_lists(server);
server->mount_time = jiffies;
nfs_free_fattr(fattr);
return server;
@@ -1342,11 +1356,7 @@ static int nfs4_server_common_setup(struct nfs_server *server,
if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
server->namelen = NFS4_MAXNAMLEN;

- spin_lock(&nfs_client_lock);
- list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
- list_add_tail(&server->master_link, &nfs_volume_list);
- spin_unlock(&nfs_client_lock);
-
+ nfs_server_insert_lists(server);
server->mount_time = jiffies;
out:
nfs_free_fattr(fattr);
@@ -1551,11 +1561,7 @@ struct nfs_server *nfs_clone_server(struct nfs_server *source,
if (error < 0)
goto out_free_server;

- spin_lock(&nfs_client_lock);
- list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
- list_add_tail(&server->master_link, &nfs_volume_list);
- spin_unlock(&nfs_client_lock);
-
+ nfs_server_insert_lists(server);
server->mount_time = jiffies;

nfs_free_fattr(fattr_fsinfo);
diff --git a/fs/nfs/nfs4renewd.c b/fs/nfs/nfs4renewd.c
index 72b6c58..cde5650 100644
--- a/fs/nfs/nfs4renewd.c
+++ b/fs/nfs/nfs4renewd.c
@@ -63,9 +63,14 @@ nfs4_renew_state(struct work_struct *work)

ops = clp->cl_mvops->state_renewal_ops;
dprintk("%s: start\n", __func__);
- /* Are there any active superblocks? */
- if (list_empty(&clp->cl_superblocks))
+
+ rcu_read_lock();
+ if (list_empty(&clp->cl_superblocks)) {
+ rcu_read_unlock();
goto out;
+ }
+ rcu_read_unlock();
+
spin_lock(&clp->cl_lock);
lease = clp->cl_lease_time;
last = clp->cl_last_renewal;


2010-12-24 01:32:57

by Chuck Lever

[permalink] [raw]
Subject: [PATCH 3/4] NFS: Introduce nfs_detach_delegations()

Clean up: Refactor code that takes clp->cl_lock and calls
nfs_detach_delegations_locked() into its own function.

While we're changing the call sites, get rid of the second parameter
and the logic in nfs_detach_delegations_locked() that uses it, since
callers always set that parameter of nfs_detach_delegations_locked()
to NULL.

Signed-off-by: Chuck Lever <[email protected]>
---

fs/nfs/delegation.c | 41 ++++++++++++++++++++---------------------
1 files changed, 20 insertions(+), 21 deletions(-)

diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index 1fd62fc..521d71b 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -175,9 +175,9 @@ static struct inode *nfs_delegation_grab_inode(struct nfs_delegation *delegation
return inode;
}

-static struct nfs_delegation *nfs_detach_delegation_locked(struct nfs_inode *nfsi,
- const nfs4_stateid *stateid,
- struct nfs_client *clp)
+static struct nfs_delegation *
+nfs_detach_delegation_locked(struct nfs_inode *nfsi,
+ struct nfs_client *clp)
{
struct nfs_delegation *delegation =
rcu_dereference_protected(nfsi->delegation,
@@ -185,22 +185,29 @@ static struct nfs_delegation *nfs_detach_delegation_locked(struct nfs_inode *nfs

if (delegation == NULL)
goto nomatch;
+
spin_lock(&delegation->lock);
- if (stateid != NULL && memcmp(delegation->stateid.data, stateid->data,
- sizeof(delegation->stateid.data)) != 0)
- goto nomatch_unlock;
list_del_rcu(&delegation->super_list);
delegation->inode = NULL;
nfsi->delegation_state = 0;
rcu_assign_pointer(nfsi->delegation, NULL);
spin_unlock(&delegation->lock);
return delegation;
-nomatch_unlock:
- spin_unlock(&delegation->lock);
nomatch:
return NULL;
}

+static struct nfs_delegation *nfs_detach_delegation(struct nfs_inode *nfsi,
+ struct nfs_client *clp)
+{
+ struct nfs_delegation *delegation;
+
+ spin_lock(&clp->cl_lock);
+ delegation = nfs_detach_delegation_locked(nfsi, clp);
+ spin_unlock(&clp->cl_lock);
+ return delegation;
+}
+
/*
* Set up a delegation on an inode
*/
@@ -246,7 +253,7 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
delegation = NULL;
goto out;
}
- freeme = nfs_detach_delegation_locked(nfsi, NULL, clp);
+ freeme = nfs_detach_delegation_locked(nfsi, clp);
}
list_add_rcu(&delegation->super_list, &clp->cl_delegations);
nfsi->delegation_state = delegation->type;
@@ -307,9 +314,7 @@ restart:
inode = nfs_delegation_grab_inode(delegation);
if (inode == NULL)
continue;
- spin_lock(&clp->cl_lock);
- delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL, clp);
- spin_unlock(&clp->cl_lock);
+ delegation = nfs_detach_delegation(NFS_I(inode), clp);
rcu_read_unlock();
if (delegation != NULL) {
filemap_flush(inode->i_mapping);
@@ -338,9 +343,7 @@ void nfs_inode_return_delegation_noreclaim(struct inode *inode)
struct nfs_delegation *delegation;

if (rcu_access_pointer(nfsi->delegation) != NULL) {
- spin_lock(&clp->cl_lock);
- delegation = nfs_detach_delegation_locked(nfsi, NULL, clp);
- spin_unlock(&clp->cl_lock);
+ delegation = nfs_detach_delegation(nfsi, clp);
if (delegation != NULL)
nfs_do_return_delegation(inode, delegation, 0);
}
@@ -354,9 +357,7 @@ int nfs_inode_return_delegation(struct inode *inode)
int err = 0;

if (rcu_access_pointer(nfsi->delegation) != NULL) {
- spin_lock(&clp->cl_lock);
- delegation = nfs_detach_delegation_locked(nfsi, NULL, clp);
- spin_unlock(&clp->cl_lock);
+ delegation = nfs_detach_delegation(nfsi, clp);
if (delegation != NULL) {
nfs_wb_all(inode);
err = __nfs_inode_return_delegation(inode, delegation, 1);
@@ -530,9 +531,7 @@ restart:
inode = nfs_delegation_grab_inode(delegation);
if (inode == NULL)
continue;
- spin_lock(&clp->cl_lock);
- delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL, clp);
- spin_unlock(&clp->cl_lock);
+ delegation = nfs_detach_delegation(NFS_I(inode), clp);
rcu_read_unlock();
if (delegation != NULL)
nfs_free_delegation(delegation);


2010-12-24 01:33:08

by Chuck Lever

[permalink] [raw]
Subject: [PATCH 4/4] 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 <[email protected]>
---

fs/nfs/client.c | 2
fs/nfs/delegation.c | 337 +++++++++++++++++++++++++++++++++------------
fs/nfs/delegation.h | 1
fs/nfs/nfs4renewd.c | 2
include/linux/nfs_fs_sb.h | 2
5 files changed, 251 insertions(+), 93 deletions(-)

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 05e2ee2..4007031 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -144,7 +144,6 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
clp->cl_proto = cl_init->proto;

#ifdef CONFIG_NFS_V4
- INIT_LIST_HEAD(&clp->cl_delegations);
spin_lock_init(&clp->cl_lock);
INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
@@ -1025,6 +1024,7 @@ static struct nfs_server *nfs_alloc_server(void)
/* Zero out the NFS state stuff */
INIT_LIST_HEAD(&server->client_link);
INIT_LIST_HEAD(&server->master_link);
+ INIT_LIST_HEAD(&server->delegations);

atomic_set(&server->active, 0);

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 @@ static void nfs_free_delegation(struct nfs_delegation *delegation)
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 @@ again:
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 inode *nfs_delegation_grab_inode(struct nfs_delegation *delegation

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 @@ nomatch:
}

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 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct

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 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
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 @@ out:
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 @@ int nfs_inode_return_delegation(struct inode *inode)
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 @@ static void nfs_delegation_run_state_manager(struct nfs_client *clp)
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 @@ void nfs_handle_cb_pathdown(struct nfs_client *clp)
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 @@ int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *s
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 @@ struct inode *nfs_delegation_find_inode(struct nfs_client *clp, const struct nfs
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);
diff --git a/fs/nfs/delegation.h b/fs/nfs/delegation.h
index 2026304..d9322e4 100644
--- a/fs/nfs/delegation.h
+++ b/fs/nfs/delegation.h
@@ -44,6 +44,7 @@ void nfs_expire_all_delegation_types(struct nfs_client *clp, fmode_t flags);
void nfs_expire_unreferenced_delegations(struct nfs_client *clp);
void nfs_handle_cb_pathdown(struct nfs_client *clp);
int nfs_client_return_marked_delegations(struct nfs_client *clp);
+int nfs_delegations_present(struct nfs_client *clp);

void nfs_delegation_mark_reclaim(struct nfs_client *clp);
void nfs_delegation_reap_unclaimed(struct nfs_client *clp);
diff --git a/fs/nfs/nfs4renewd.c b/fs/nfs/nfs4renewd.c
index cde5650..402143d 100644
--- a/fs/nfs/nfs4renewd.c
+++ b/fs/nfs/nfs4renewd.c
@@ -80,7 +80,7 @@ nfs4_renew_state(struct work_struct *work)
cred = ops->get_state_renewal_cred_locked(clp);
spin_unlock(&clp->cl_lock);
if (cred == NULL) {
- if (list_empty(&clp->cl_delegations)) {
+ if (!nfs_delegations_present(clp)) {
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
goto out;
}
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index e96ec55..17881c0 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -47,7 +47,6 @@ struct nfs_client {
u64 cl_clientid; /* constant */
unsigned long cl_state;

- struct list_head cl_delegations;
spinlock_t cl_lock;

unsigned long cl_lease_time;
@@ -150,6 +149,7 @@ struct nfs_server {
struct rb_root openowner_id;
struct rb_root lockowner_id;
#endif
+ struct list_head delegations;
void (*destroy)(struct nfs_server *);

atomic_t active; /* Keep trace of any activity to this server */


2010-12-23 22:15:52

by Chuck Lever

[permalink] [raw]
Subject: Re: [PATCH 4/4] NFS: Move cl_delegations to the nfs_server struct


On Dec 23, 2010, at 5:09 PM, Trond Myklebust wrote:

> On Thu, 2010-12-23 at 16:54 -0500, Chuck Lever wrote:
>> 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 <[email protected]>
>> ---
>>
>> fs/nfs/client.c | 4 -
>> fs/nfs/delegation.c | 337 +++++++++++++++++++++++++++++++++------------
>> fs/nfs/delegation.h | 1
>> fs/nfs/nfs4renewd.c | 2
>> include/linux/nfs_fs_sb.h | 2
>> 5 files changed, 253 insertions(+), 93 deletions(-)
>>
>> diff --git a/fs/nfs/client.c b/fs/nfs/client.c
>> index 05e2ee2..d112887 100644
>> --- a/fs/nfs/client.c
>> +++ b/fs/nfs/client.c
>> @@ -144,7 +144,6 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
>> clp->cl_proto = cl_init->proto;
>>
>> #ifdef CONFIG_NFS_V4
>> - INIT_LIST_HEAD(&clp->cl_delegations);
>> spin_lock_init(&clp->cl_lock);
>> INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
>> rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
>> @@ -1025,6 +1024,9 @@ static struct nfs_server *nfs_alloc_server(void)
>> /* Zero out the NFS state stuff */
>> INIT_LIST_HEAD(&server->client_link);
>> INIT_LIST_HEAD(&server->master_link);
>> +#ifdef CONFIG_NFS_V4
>> + INIT_LIST_HEAD(&server->delegations);
>> +#endif
>
> As I said earlier, can we please avoid this? Just define the
> 'delegations' field unconditionally in struct nfs_server, and get rid of
> the CONFIG_NFS_V4 above.

Sorry, dude. I forgot that one.

>
> Cheers
> Trond
>
>> atomic_set(&server->active, 0);
>
>
>
>> diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
>> index e96ec55..2ddf7aa 100644
>> --- a/include/linux/nfs_fs_sb.h
>> +++ b/include/linux/nfs_fs_sb.h
>> @@ -47,7 +47,6 @@ struct nfs_client {
>> u64 cl_clientid; /* constant */
>> unsigned long cl_state;
>>
>> - struct list_head cl_delegations;
>> spinlock_t cl_lock;
>>
>> unsigned long cl_lease_time;
>> @@ -149,6 +148,7 @@ struct nfs_server {
>> struct rb_root state_owners;
>> struct rb_root openowner_id;
>> struct rb_root lockowner_id;
>> + struct list_head delegations;
>> #endif
>> void (*destroy)(struct nfs_server *);
>>
>>
>
> --
> Trond Myklebust
> Linux NFS client maintainer
>
> NetApp
> [email protected]
> http://www.netapp.com
>

--
Chuck Lever
chuck[dot]lever[at]oracle[dot]com





2011-03-04 22:45:42

by Frank Filz

[permalink] [raw]
Subject: Re: [PATCH 0/4] Refactor data structures to support NFSv4 migration (2)


Chuck, Trond,

What is the outlook for the client patchset for migration?

Thanks

Frank Filz



2011-03-04 22:58:16

by Chuck Lever

[permalink] [raw]
Subject: Re: [PATCH 0/4] Refactor data structures to support NFSv4 migration (2)


On Mar 4, 2011, at 5:45 PM, Frank Filz wrote:

>
> Chuck, Trond,
>
> What is the outlook for the client patchset for migration?

Trond and I are going to meet next week to go over the prototype and roadmap. I'll post something for people to review soon. Client-side migration will likely go in 2.6.40, but that's up to Trond.

--
Chuck Lever
chuck[dot]lever[at]oracle[dot]com