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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/nfs/nfs4state.c
downloadlwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/nfs/nfs4state.c')
-rw-r--r--fs/nfs/nfs4state.c932
1 files changed, 932 insertions, 0 deletions
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
new file mode 100644
index 000000000000..231cebce3c87
--- /dev/null
+++ b/fs/nfs/nfs4state.c
@@ -0,0 +1,932 @@
+/*
+ * fs/nfs/nfs4state.c
+ *
+ * Client-side XDR for NFSv4.
+ *
+ * Copyright (c) 2002 The Regents of the University of Michigan.
+ * All rights reserved.
+ *
+ * Kendrick Smith <kmsmith@umich.edu>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Implementation of the NFSv4 state model. For the time being,
+ * this is minimal, but will be made much more complex in a
+ * subsequent patch.
+ */
+
+#include <linux/config.h>
+#include <linux/slab.h>
+#include <linux/smp_lock.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_idmap.h>
+#include <linux/workqueue.h>
+#include <linux/bitops.h>
+
+#include "callback.h"
+#include "delegation.h"
+
+#define OPENOWNER_POOL_SIZE 8
+
+static DEFINE_SPINLOCK(state_spinlock);
+
+nfs4_stateid zero_stateid;
+
+#if 0
+nfs4_stateid one_stateid =
+ { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
+#endif
+
+static LIST_HEAD(nfs4_clientid_list);
+
+static void nfs4_recover_state(void *);
+extern void nfs4_renew_state(void *);
+
+void
+init_nfsv4_state(struct nfs_server *server)
+{
+ server->nfs4_state = NULL;
+ INIT_LIST_HEAD(&server->nfs4_siblings);
+}
+
+void
+destroy_nfsv4_state(struct nfs_server *server)
+{
+ if (server->mnt_path) {
+ kfree(server->mnt_path);
+ server->mnt_path = NULL;
+ }
+ if (server->nfs4_state) {
+ nfs4_put_client(server->nfs4_state);
+ server->nfs4_state = NULL;
+ }
+}
+
+/*
+ * nfs4_get_client(): returns an empty client structure
+ * nfs4_put_client(): drops reference to client structure
+ *
+ * Since these are allocated/deallocated very rarely, we don't
+ * bother putting them in a slab cache...
+ */
+static struct nfs4_client *
+nfs4_alloc_client(struct in_addr *addr)
+{
+ struct nfs4_client *clp;
+
+ if (nfs_callback_up() < 0)
+ return NULL;
+ if ((clp = kmalloc(sizeof(*clp), GFP_KERNEL)) == NULL) {
+ nfs_callback_down();
+ return NULL;
+ }
+ memset(clp, 0, sizeof(*clp));
+ memcpy(&clp->cl_addr, addr, sizeof(clp->cl_addr));
+ init_rwsem(&clp->cl_sem);
+ INIT_LIST_HEAD(&clp->cl_delegations);
+ INIT_LIST_HEAD(&clp->cl_state_owners);
+ INIT_LIST_HEAD(&clp->cl_unused);
+ spin_lock_init(&clp->cl_lock);
+ atomic_set(&clp->cl_count, 1);
+ INIT_WORK(&clp->cl_recoverd, nfs4_recover_state, clp);
+ INIT_WORK(&clp->cl_renewd, nfs4_renew_state, clp);
+ INIT_LIST_HEAD(&clp->cl_superblocks);
+ init_waitqueue_head(&clp->cl_waitq);
+ rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS4 client");
+ clp->cl_boot_time = CURRENT_TIME;
+ clp->cl_state = 1 << NFS4CLNT_OK;
+ return clp;
+}
+
+static void
+nfs4_free_client(struct nfs4_client *clp)
+{
+ struct nfs4_state_owner *sp;
+
+ while (!list_empty(&clp->cl_unused)) {
+ sp = list_entry(clp->cl_unused.next,
+ struct nfs4_state_owner,
+ so_list);
+ list_del(&sp->so_list);
+ kfree(sp);
+ }
+ BUG_ON(!list_empty(&clp->cl_state_owners));
+ if (clp->cl_cred)
+ put_rpccred(clp->cl_cred);
+ nfs_idmap_delete(clp);
+ if (clp->cl_rpcclient)
+ rpc_shutdown_client(clp->cl_rpcclient);
+ kfree(clp);
+ nfs_callback_down();
+}
+
+static struct nfs4_client *__nfs4_find_client(struct in_addr *addr)
+{
+ struct nfs4_client *clp;
+ list_for_each_entry(clp, &nfs4_clientid_list, cl_servers) {
+ if (memcmp(&clp->cl_addr, addr, sizeof(clp->cl_addr)) == 0) {
+ atomic_inc(&clp->cl_count);
+ return clp;
+ }
+ }
+ return NULL;
+}
+
+struct nfs4_client *nfs4_find_client(struct in_addr *addr)
+{
+ struct nfs4_client *clp;
+ spin_lock(&state_spinlock);
+ clp = __nfs4_find_client(addr);
+ spin_unlock(&state_spinlock);
+ return clp;
+}
+
+struct nfs4_client *
+nfs4_get_client(struct in_addr *addr)
+{
+ struct nfs4_client *clp, *new = NULL;
+
+ spin_lock(&state_spinlock);
+ for (;;) {
+ clp = __nfs4_find_client(addr);
+ if (clp != NULL)
+ break;
+ clp = new;
+ if (clp != NULL) {
+ list_add(&clp->cl_servers, &nfs4_clientid_list);
+ new = NULL;
+ break;
+ }
+ spin_unlock(&state_spinlock);
+ new = nfs4_alloc_client(addr);
+ spin_lock(&state_spinlock);
+ if (new == NULL)
+ break;
+ }
+ spin_unlock(&state_spinlock);
+ if (new)
+ nfs4_free_client(new);
+ return clp;
+}
+
+void
+nfs4_put_client(struct nfs4_client *clp)
+{
+ if (!atomic_dec_and_lock(&clp->cl_count, &state_spinlock))
+ return;
+ list_del(&clp->cl_servers);
+ spin_unlock(&state_spinlock);
+ BUG_ON(!list_empty(&clp->cl_superblocks));
+ wake_up_all(&clp->cl_waitq);
+ rpc_wake_up(&clp->cl_rpcwaitq);
+ nfs4_kill_renewd(clp);
+ nfs4_free_client(clp);
+}
+
+static int __nfs4_init_client(struct nfs4_client *clp)
+{
+ int status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, nfs_callback_tcpport);
+ if (status == 0)
+ status = nfs4_proc_setclientid_confirm(clp);
+ if (status == 0)
+ nfs4_schedule_state_renewal(clp);
+ return status;
+}
+
+int nfs4_init_client(struct nfs4_client *clp)
+{
+ return nfs4_map_errors(__nfs4_init_client(clp));
+}
+
+u32
+nfs4_alloc_lockowner_id(struct nfs4_client *clp)
+{
+ return clp->cl_lockowner_id ++;
+}
+
+static struct nfs4_state_owner *
+nfs4_client_grab_unused(struct nfs4_client *clp, struct rpc_cred *cred)
+{
+ struct nfs4_state_owner *sp = NULL;
+
+ if (!list_empty(&clp->cl_unused)) {
+ sp = list_entry(clp->cl_unused.next, struct nfs4_state_owner, so_list);
+ atomic_inc(&sp->so_count);
+ sp->so_cred = cred;
+ list_move(&sp->so_list, &clp->cl_state_owners);
+ clp->cl_nunused--;
+ }
+ return sp;
+}
+
+static struct nfs4_state_owner *
+nfs4_find_state_owner(struct nfs4_client *clp, struct rpc_cred *cred)
+{
+ struct nfs4_state_owner *sp, *res = NULL;
+
+ list_for_each_entry(sp, &clp->cl_state_owners, so_list) {
+ if (sp->so_cred != cred)
+ continue;
+ atomic_inc(&sp->so_count);
+ /* Move to the head of the list */
+ list_move(&sp->so_list, &clp->cl_state_owners);
+ res = sp;
+ break;
+ }
+ return res;
+}
+
+/*
+ * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
+ * create a new state_owner.
+ *
+ */
+static struct nfs4_state_owner *
+nfs4_alloc_state_owner(void)
+{
+ struct nfs4_state_owner *sp;
+
+ sp = kmalloc(sizeof(*sp),GFP_KERNEL);
+ if (!sp)
+ return NULL;
+ init_MUTEX(&sp->so_sema);
+ sp->so_seqid = 0; /* arbitrary */
+ INIT_LIST_HEAD(&sp->so_states);
+ INIT_LIST_HEAD(&sp->so_delegations);
+ atomic_set(&sp->so_count, 1);
+ return sp;
+}
+
+void
+nfs4_drop_state_owner(struct nfs4_state_owner *sp)
+{
+ struct nfs4_client *clp = sp->so_client;
+ spin_lock(&clp->cl_lock);
+ list_del_init(&sp->so_list);
+ spin_unlock(&clp->cl_lock);
+}
+
+/*
+ * Note: must be called with clp->cl_sem held in order to prevent races
+ * with reboot recovery!
+ */
+struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
+{
+ struct nfs4_client *clp = server->nfs4_state;
+ struct nfs4_state_owner *sp, *new;
+
+ get_rpccred(cred);
+ new = nfs4_alloc_state_owner();
+ spin_lock(&clp->cl_lock);
+ sp = nfs4_find_state_owner(clp, cred);
+ if (sp == NULL)
+ sp = nfs4_client_grab_unused(clp, cred);
+ if (sp == NULL && new != NULL) {
+ list_add(&new->so_list, &clp->cl_state_owners);
+ new->so_client = clp;
+ new->so_id = nfs4_alloc_lockowner_id(clp);
+ new->so_cred = cred;
+ sp = new;
+ new = NULL;
+ }
+ spin_unlock(&clp->cl_lock);
+ if (new)
+ kfree(new);
+ if (sp != NULL)
+ return sp;
+ put_rpccred(cred);
+ return NULL;
+}
+
+/*
+ * Must be called with clp->cl_sem held in order to avoid races
+ * with state recovery...
+ */
+void nfs4_put_state_owner(struct nfs4_state_owner *sp)
+{
+ struct nfs4_client *clp = sp->so_client;
+ struct rpc_cred *cred = sp->so_cred;
+
+ if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
+ return;
+ if (clp->cl_nunused >= OPENOWNER_POOL_SIZE)
+ goto out_free;
+ if (list_empty(&sp->so_list))
+ goto out_free;
+ list_move(&sp->so_list, &clp->cl_unused);
+ clp->cl_nunused++;
+ spin_unlock(&clp->cl_lock);
+ put_rpccred(cred);
+ cred = NULL;
+ return;
+out_free:
+ list_del(&sp->so_list);
+ spin_unlock(&clp->cl_lock);
+ put_rpccred(cred);
+ kfree(sp);
+}
+
+static struct nfs4_state *
+nfs4_alloc_open_state(void)
+{
+ struct nfs4_state *state;
+
+ state = kmalloc(sizeof(*state), GFP_KERNEL);
+ if (!state)
+ return NULL;
+ state->state = 0;
+ state->nreaders = 0;
+ state->nwriters = 0;
+ state->flags = 0;
+ memset(state->stateid.data, 0, sizeof(state->stateid.data));
+ atomic_set(&state->count, 1);
+ INIT_LIST_HEAD(&state->lock_states);
+ init_MUTEX(&state->lock_sema);
+ rwlock_init(&state->state_lock);
+ return state;
+}
+
+static struct nfs4_state *
+__nfs4_find_state(struct inode *inode, struct rpc_cred *cred, mode_t mode)
+{
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct nfs4_state *state;
+
+ mode &= (FMODE_READ|FMODE_WRITE);
+ list_for_each_entry(state, &nfsi->open_states, inode_states) {
+ if (state->owner->so_cred != cred)
+ continue;
+ if ((mode & FMODE_READ) != 0 && state->nreaders == 0)
+ continue;
+ if ((mode & FMODE_WRITE) != 0 && state->nwriters == 0)
+ continue;
+ if ((state->state & mode) != mode)
+ continue;
+ atomic_inc(&state->count);
+ if (mode & FMODE_READ)
+ state->nreaders++;
+ if (mode & FMODE_WRITE)
+ state->nwriters++;
+ return state;
+ }
+ return NULL;
+}
+
+static struct nfs4_state *
+__nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
+{
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct nfs4_state *state;
+
+ list_for_each_entry(state, &nfsi->open_states, inode_states) {
+ /* Is this in the process of being freed? */
+ if (state->nreaders == 0 && state->nwriters == 0)
+ continue;
+ if (state->owner == owner) {
+ atomic_inc(&state->count);
+ return state;
+ }
+ }
+ return NULL;
+}
+
+struct nfs4_state *
+nfs4_find_state(struct inode *inode, struct rpc_cred *cred, mode_t mode)
+{
+ struct nfs4_state *state;
+
+ spin_lock(&inode->i_lock);
+ state = __nfs4_find_state(inode, cred, mode);
+ spin_unlock(&inode->i_lock);
+ return state;
+}
+
+static void
+nfs4_free_open_state(struct nfs4_state *state)
+{
+ kfree(state);
+}
+
+struct nfs4_state *
+nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
+{
+ struct nfs4_state *state, *new;
+ struct nfs_inode *nfsi = NFS_I(inode);
+
+ spin_lock(&inode->i_lock);
+ state = __nfs4_find_state_byowner(inode, owner);
+ spin_unlock(&inode->i_lock);
+ if (state)
+ goto out;
+ new = nfs4_alloc_open_state();
+ spin_lock(&inode->i_lock);
+ state = __nfs4_find_state_byowner(inode, owner);
+ if (state == NULL && new != NULL) {
+ state = new;
+ /* Caller *must* be holding owner->so_sem */
+ /* Note: The reclaim code dictates that we add stateless
+ * and read-only stateids to the end of the list */
+ list_add_tail(&state->open_states, &owner->so_states);
+ state->owner = owner;
+ atomic_inc(&owner->so_count);
+ list_add(&state->inode_states, &nfsi->open_states);
+ state->inode = igrab(inode);
+ spin_unlock(&inode->i_lock);
+ } else {
+ spin_unlock(&inode->i_lock);
+ if (new)
+ nfs4_free_open_state(new);
+ }
+out:
+ return state;
+}
+
+/*
+ * Beware! Caller must be holding exactly one
+ * reference to clp->cl_sem and owner->so_sema!
+ */
+void nfs4_put_open_state(struct nfs4_state *state)
+{
+ struct inode *inode = state->inode;
+ struct nfs4_state_owner *owner = state->owner;
+
+ if (!atomic_dec_and_lock(&state->count, &inode->i_lock))
+ return;
+ if (!list_empty(&state->inode_states))
+ list_del(&state->inode_states);
+ spin_unlock(&inode->i_lock);
+ list_del(&state->open_states);
+ iput(inode);
+ BUG_ON (state->state != 0);
+ nfs4_free_open_state(state);
+ nfs4_put_state_owner(owner);
+}
+
+/*
+ * Beware! Caller must be holding no references to clp->cl_sem!
+ * of owner->so_sema!
+ */
+void nfs4_close_state(struct nfs4_state *state, mode_t mode)
+{
+ struct inode *inode = state->inode;
+ struct nfs4_state_owner *owner = state->owner;
+ struct nfs4_client *clp = owner->so_client;
+ int newstate;
+
+ atomic_inc(&owner->so_count);
+ down_read(&clp->cl_sem);
+ down(&owner->so_sema);
+ /* Protect against nfs4_find_state() */
+ spin_lock(&inode->i_lock);
+ if (mode & FMODE_READ)
+ state->nreaders--;
+ if (mode & FMODE_WRITE)
+ state->nwriters--;
+ if (state->nwriters == 0) {
+ if (state->nreaders == 0)
+ list_del_init(&state->inode_states);
+ /* See reclaim code */
+ list_move_tail(&state->open_states, &owner->so_states);
+ }
+ spin_unlock(&inode->i_lock);
+ newstate = 0;
+ if (state->state != 0) {
+ if (state->nreaders)
+ newstate |= FMODE_READ;
+ if (state->nwriters)
+ newstate |= FMODE_WRITE;
+ if (state->state == newstate)
+ goto out;
+ if (nfs4_do_close(inode, state, newstate) == -EINPROGRESS)
+ return;
+ }
+out:
+ nfs4_put_open_state(state);
+ up(&owner->so_sema);
+ nfs4_put_state_owner(owner);
+ up_read(&clp->cl_sem);
+}
+
+/*
+ * Search the state->lock_states for an existing lock_owner
+ * that is compatible with current->files
+ */
+static struct nfs4_lock_state *
+__nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
+{
+ struct nfs4_lock_state *pos;
+ list_for_each_entry(pos, &state->lock_states, ls_locks) {
+ if (pos->ls_owner != fl_owner)
+ continue;
+ atomic_inc(&pos->ls_count);
+ return pos;
+ }
+ return NULL;
+}
+
+struct nfs4_lock_state *
+nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
+{
+ struct nfs4_lock_state *lsp;
+ read_lock(&state->state_lock);
+ lsp = __nfs4_find_lock_state(state, fl_owner);
+ read_unlock(&state->state_lock);
+ return lsp;
+}
+
+/*
+ * Return a compatible lock_state. If no initialized lock_state structure
+ * exists, return an uninitialized one.
+ *
+ * The caller must be holding state->lock_sema
+ */
+static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
+{
+ struct nfs4_lock_state *lsp;
+ struct nfs4_client *clp = state->owner->so_client;
+
+ lsp = kmalloc(sizeof(*lsp), GFP_KERNEL);
+ if (lsp == NULL)
+ return NULL;
+ lsp->ls_flags = 0;
+ lsp->ls_seqid = 0; /* arbitrary */
+ lsp->ls_id = -1;
+ memset(lsp->ls_stateid.data, 0, sizeof(lsp->ls_stateid.data));
+ atomic_set(&lsp->ls_count, 1);
+ lsp->ls_owner = fl_owner;
+ INIT_LIST_HEAD(&lsp->ls_locks);
+ spin_lock(&clp->cl_lock);
+ lsp->ls_id = nfs4_alloc_lockowner_id(clp);
+ spin_unlock(&clp->cl_lock);
+ return lsp;
+}
+
+/*
+ * Return a compatible lock_state. If no initialized lock_state structure
+ * exists, return an uninitialized one.
+ *
+ * The caller must be holding state->lock_sema and clp->cl_sem
+ */
+struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
+{
+ struct nfs4_lock_state * lsp;
+
+ lsp = nfs4_find_lock_state(state, owner);
+ if (lsp == NULL)
+ lsp = nfs4_alloc_lock_state(state, owner);
+ return lsp;
+}
+
+/*
+ * Byte-range lock aware utility to initialize the stateid of read/write
+ * requests.
+ */
+void
+nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner)
+{
+ if (test_bit(LK_STATE_IN_USE, &state->flags)) {
+ struct nfs4_lock_state *lsp;
+
+ lsp = nfs4_find_lock_state(state, fl_owner);
+ if (lsp) {
+ memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
+ nfs4_put_lock_state(lsp);
+ return;
+ }
+ }
+ memcpy(dst, &state->stateid, sizeof(*dst));
+}
+
+/*
+* Called with state->lock_sema and clp->cl_sem held.
+*/
+void nfs4_increment_lock_seqid(int status, struct nfs4_lock_state *lsp)
+{
+ if (status == NFS_OK || seqid_mutating_err(-status))
+ lsp->ls_seqid++;
+}
+
+/*
+* Check to see if the request lock (type FL_UNLK) effects the fl lock.
+*
+* fl and request must have the same posix owner
+*
+* return:
+* 0 -> fl not effected by request
+* 1 -> fl consumed by request
+*/
+
+static int
+nfs4_check_unlock(struct file_lock *fl, struct file_lock *request)
+{
+ if (fl->fl_start >= request->fl_start && fl->fl_end <= request->fl_end)
+ return 1;
+ return 0;
+}
+
+/*
+ * Post an initialized lock_state on the state->lock_states list.
+ */
+void nfs4_notify_setlk(struct nfs4_state *state, struct file_lock *request, struct nfs4_lock_state *lsp)
+{
+ if (!list_empty(&lsp->ls_locks))
+ return;
+ atomic_inc(&lsp->ls_count);
+ write_lock(&state->state_lock);
+ list_add(&lsp->ls_locks, &state->lock_states);
+ set_bit(LK_STATE_IN_USE, &state->flags);
+ write_unlock(&state->state_lock);
+}
+
+/*
+ * to decide to 'reap' lock state:
+ * 1) search i_flock for file_locks with fl.lock_state = to ls.
+ * 2) determine if unlock will consume found lock.
+ * if so, reap
+ *
+ * else, don't reap.
+ *
+ */
+void
+nfs4_notify_unlck(struct nfs4_state *state, struct file_lock *request, struct nfs4_lock_state *lsp)
+{
+ struct inode *inode = state->inode;
+ struct file_lock *fl;
+
+ for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
+ if (!(fl->fl_flags & FL_POSIX))
+ continue;
+ if (fl->fl_owner != lsp->ls_owner)
+ continue;
+ /* Exit if we find at least one lock which is not consumed */
+ if (nfs4_check_unlock(fl,request) == 0)
+ return;
+ }
+
+ write_lock(&state->state_lock);
+ list_del_init(&lsp->ls_locks);
+ if (list_empty(&state->lock_states))
+ clear_bit(LK_STATE_IN_USE, &state->flags);
+ write_unlock(&state->state_lock);
+ nfs4_put_lock_state(lsp);
+}
+
+/*
+ * Release reference to lock_state, and free it if we see that
+ * it is no longer in use
+ */
+void
+nfs4_put_lock_state(struct nfs4_lock_state *lsp)
+{
+ if (!atomic_dec_and_test(&lsp->ls_count))
+ return;
+ BUG_ON (!list_empty(&lsp->ls_locks));
+ kfree(lsp);
+}
+
+/*
+* Called with sp->so_sema and clp->cl_sem held.
+*
+* Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
+* failed with a seqid incrementing error -
+* see comments nfs_fs.h:seqid_mutating_error()
+*/
+void nfs4_increment_seqid(int status, struct nfs4_state_owner *sp)
+{
+ if (status == NFS_OK || seqid_mutating_err(-status))
+ sp->so_seqid++;
+ /* If the server returns BAD_SEQID, unhash state_owner here */
+ if (status == -NFS4ERR_BAD_SEQID)
+ nfs4_drop_state_owner(sp);
+}
+
+static int reclaimer(void *);
+struct reclaimer_args {
+ struct nfs4_client *clp;
+ struct completion complete;
+};
+
+/*
+ * State recovery routine
+ */
+void
+nfs4_recover_state(void *data)
+{
+ struct nfs4_client *clp = (struct nfs4_client *)data;
+ struct reclaimer_args args = {
+ .clp = clp,
+ };
+ might_sleep();
+
+ init_completion(&args.complete);
+
+ if (kernel_thread(reclaimer, &args, CLONE_KERNEL) < 0)
+ goto out_failed_clear;
+ wait_for_completion(&args.complete);
+ return;
+out_failed_clear:
+ set_bit(NFS4CLNT_OK, &clp->cl_state);
+ wake_up_all(&clp->cl_waitq);
+ rpc_wake_up(&clp->cl_rpcwaitq);
+}
+
+/*
+ * Schedule a state recovery attempt
+ */
+void
+nfs4_schedule_state_recovery(struct nfs4_client *clp)
+{
+ if (!clp)
+ return;
+ if (test_and_clear_bit(NFS4CLNT_OK, &clp->cl_state))
+ schedule_work(&clp->cl_recoverd);
+}
+
+static int nfs4_reclaim_locks(struct nfs4_state_recovery_ops *ops, struct nfs4_state *state)
+{
+ struct inode *inode = state->inode;
+ struct file_lock *fl;
+ int status = 0;
+
+ for (fl = inode->i_flock; fl != 0; fl = fl->fl_next) {
+ if (!(fl->fl_flags & FL_POSIX))
+ continue;
+ if (((struct nfs_open_context *)fl->fl_file->private_data)->state != state)
+ continue;
+ status = ops->recover_lock(state, fl);
+ if (status >= 0)
+ continue;
+ switch (status) {
+ default:
+ printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
+ __FUNCTION__, status);
+ case -NFS4ERR_EXPIRED:
+ case -NFS4ERR_NO_GRACE:
+ case -NFS4ERR_RECLAIM_BAD:
+ case -NFS4ERR_RECLAIM_CONFLICT:
+ /* kill_proc(fl->fl_owner, SIGLOST, 1); */
+ break;
+ case -NFS4ERR_STALE_CLIENTID:
+ goto out_err;
+ }
+ }
+ return 0;
+out_err:
+ return status;
+}
+
+static int nfs4_reclaim_open_state(struct nfs4_state_recovery_ops *ops, struct nfs4_state_owner *sp)
+{
+ struct nfs4_state *state;
+ struct nfs4_lock_state *lock;
+ int status = 0;
+
+ /* Note: we rely on the sp->so_states list being ordered
+ * so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
+ * states first.
+ * This is needed to ensure that the server won't give us any
+ * read delegations that we have to return if, say, we are
+ * recovering after a network partition or a reboot from a
+ * server that doesn't support a grace period.
+ */
+ list_for_each_entry(state, &sp->so_states, open_states) {
+ if (state->state == 0)
+ continue;
+ status = ops->recover_open(sp, state);
+ list_for_each_entry(lock, &state->lock_states, ls_locks)
+ lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
+ if (status >= 0) {
+ status = nfs4_reclaim_locks(ops, state);
+ if (status < 0)
+ goto out_err;
+ list_for_each_entry(lock, &state->lock_states, ls_locks) {
+ if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
+ printk("%s: Lock reclaim failed!\n",
+ __FUNCTION__);
+ }
+ continue;
+ }
+ switch (status) {
+ default:
+ printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
+ __FUNCTION__, status);
+ case -ENOENT:
+ case -NFS4ERR_RECLAIM_BAD:
+ case -NFS4ERR_RECLAIM_CONFLICT:
+ /*
+ * Open state on this file cannot be recovered
+ * All we can do is revert to using the zero stateid.
+ */
+ memset(state->stateid.data, 0,
+ sizeof(state->stateid.data));
+ /* Mark the file as being 'closed' */
+ state->state = 0;
+ break;
+ case -NFS4ERR_EXPIRED:
+ case -NFS4ERR_NO_GRACE:
+ case -NFS4ERR_STALE_CLIENTID:
+ goto out_err;
+ }
+ }
+ return 0;
+out_err:
+ return status;
+}
+
+static int reclaimer(void *ptr)
+{
+ struct reclaimer_args *args = (struct reclaimer_args *)ptr;
+ struct nfs4_client *clp = args->clp;
+ struct nfs4_state_owner *sp;
+ struct nfs4_state_recovery_ops *ops;
+ int status = 0;
+
+ daemonize("%u.%u.%u.%u-reclaim", NIPQUAD(clp->cl_addr));
+ allow_signal(SIGKILL);
+
+ atomic_inc(&clp->cl_count);
+ complete(&args->complete);
+
+ /* Ensure exclusive access to NFSv4 state */
+ lock_kernel();
+ down_write(&clp->cl_sem);
+ /* Are there any NFS mounts out there? */
+ if (list_empty(&clp->cl_superblocks))
+ goto out;
+restart_loop:
+ status = nfs4_proc_renew(clp);
+ switch (status) {
+ case 0:
+ case -NFS4ERR_CB_PATH_DOWN:
+ goto out;
+ case -NFS4ERR_STALE_CLIENTID:
+ case -NFS4ERR_LEASE_MOVED:
+ ops = &nfs4_reboot_recovery_ops;
+ break;
+ default:
+ ops = &nfs4_network_partition_recovery_ops;
+ };
+ status = __nfs4_init_client(clp);
+ if (status)
+ goto out_error;
+ /* Mark all delegations for reclaim */
+ nfs_delegation_mark_reclaim(clp);
+ /* Note: list is protected by exclusive lock on cl->cl_sem */
+ list_for_each_entry(sp, &clp->cl_state_owners, so_list) {
+ status = nfs4_reclaim_open_state(ops, sp);
+ if (status < 0) {
+ if (status == -NFS4ERR_NO_GRACE) {
+ ops = &nfs4_network_partition_recovery_ops;
+ status = nfs4_reclaim_open_state(ops, sp);
+ }
+ if (status == -NFS4ERR_STALE_CLIENTID)
+ goto restart_loop;
+ if (status == -NFS4ERR_EXPIRED)
+ goto restart_loop;
+ }
+ }
+ nfs_delegation_reap_unclaimed(clp);
+out:
+ set_bit(NFS4CLNT_OK, &clp->cl_state);
+ up_write(&clp->cl_sem);
+ unlock_kernel();
+ wake_up_all(&clp->cl_waitq);
+ rpc_wake_up(&clp->cl_rpcwaitq);
+ if (status == -NFS4ERR_CB_PATH_DOWN)
+ nfs_handle_cb_pathdown(clp);
+ nfs4_put_client(clp);
+ return 0;
+out_error:
+ printk(KERN_WARNING "Error: state recovery failed on NFSv4 server %u.%u.%u.%u with error %d\n",
+ NIPQUAD(clp->cl_addr.s_addr), -status);
+ goto out;
+}
+
+/*
+ * Local variables:
+ * c-basic-offset: 8
+ * End:
+ */