| /* |
| * 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/slab.h> |
| #include <linux/smp_lock.h> |
| #include <linux/nfs_fs.h> |
| #include <linux/nfs_idmap.h> |
| #include <linux/kthread.h> |
| #include <linux/module.h> |
| #include <linux/random.h> |
| #include <linux/workqueue.h> |
| #include <linux/bitops.h> |
| |
| #include "nfs4_fs.h" |
| #include "callback.h" |
| #include "delegation.h" |
| #include "internal.h" |
| |
| #define OPENOWNER_POOL_SIZE 8 |
| |
| const nfs4_stateid zero_stateid; |
| |
| static LIST_HEAD(nfs4_clientid_list); |
| |
| static int nfs4_init_client(struct nfs_client *clp, struct rpc_cred *cred) |
| { |
| int status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, |
| nfs_callback_tcpport, cred); |
| if (status == 0) |
| status = nfs4_proc_setclientid_confirm(clp, cred); |
| if (status == 0) |
| nfs4_schedule_state_renewal(clp); |
| return status; |
| } |
| |
| struct rpc_cred *nfs4_get_renew_cred(struct nfs_client *clp) |
| { |
| 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); |
| if (list_empty(&sp->so_states)) |
| continue; |
| cred = get_rpccred(sp->so_cred); |
| break; |
| } |
| return cred; |
| } |
| |
| static struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp) |
| { |
| struct nfs4_state_owner *sp; |
| struct rb_node *pos; |
| |
| pos = rb_first(&clp->cl_state_owners); |
| if (pos != NULL) { |
| sp = rb_entry(pos, struct nfs4_state_owner, so_client_node); |
| return get_rpccred(sp->so_cred); |
| } |
| return NULL; |
| } |
| |
| static void nfs_alloc_unique_id(struct rb_root *root, struct nfs_unique_id *new, |
| __u64 minval, int maxbits) |
| { |
| struct rb_node **p, *parent; |
| struct nfs_unique_id *pos; |
| __u64 mask = ~0ULL; |
| |
| if (maxbits < 64) |
| mask = (1ULL << maxbits) - 1ULL; |
| |
| /* Ensure distribution is more or less flat */ |
| get_random_bytes(&new->id, sizeof(new->id)); |
| new->id &= mask; |
| if (new->id < minval) |
| new->id += minval; |
| retry: |
| p = &root->rb_node; |
| parent = NULL; |
| |
| while (*p != NULL) { |
| parent = *p; |
| pos = rb_entry(parent, struct nfs_unique_id, rb_node); |
| |
| if (new->id < pos->id) |
| p = &(*p)->rb_left; |
| else if (new->id > pos->id) |
| p = &(*p)->rb_right; |
| else |
| goto id_exists; |
| } |
| rb_link_node(&new->rb_node, parent, p); |
| rb_insert_color(&new->rb_node, root); |
| return; |
| id_exists: |
| for (;;) { |
| new->id++; |
| if (new->id < minval || (new->id & mask) != new->id) { |
| new->id = minval; |
| break; |
| } |
| parent = rb_next(parent); |
| if (parent == NULL) |
| break; |
| pos = rb_entry(parent, struct nfs_unique_id, rb_node); |
| if (new->id < pos->id) |
| break; |
| } |
| goto retry; |
| } |
| |
| static void nfs_free_unique_id(struct rb_root *root, struct nfs_unique_id *id) |
| { |
| rb_erase(&id->rb_node, root); |
| } |
| |
| static struct nfs4_state_owner * |
| nfs4_find_state_owner(struct nfs_client *clp, struct rpc_cred *cred) |
| { |
| struct rb_node **p = &clp->cl_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); |
| |
| if (cred < sp->so_cred) |
| p = &parent->rb_left; |
| else if (cred > sp->so_cred) |
| p = &parent->rb_right; |
| else { |
| atomic_inc(&sp->so_count); |
| res = sp; |
| break; |
| } |
| } |
| return res; |
| } |
| |
| static struct nfs4_state_owner * |
| nfs4_insert_state_owner(struct nfs_client *clp, struct nfs4_state_owner *new) |
| { |
| struct rb_node **p = &clp->cl_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); |
| |
| if (new->so_cred < sp->so_cred) |
| p = &parent->rb_left; |
| else if (new->so_cred > sp->so_cred) |
| p = &parent->rb_right; |
| else { |
| atomic_inc(&sp->so_count); |
| 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); |
| return new; |
| } |
| |
| static void |
| nfs4_remove_state_owner(struct nfs_client *clp, 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); |
| } |
| |
| /* |
| * 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 = kzalloc(sizeof(*sp),GFP_KERNEL); |
| if (!sp) |
| return NULL; |
| spin_lock_init(&sp->so_lock); |
| INIT_LIST_HEAD(&sp->so_states); |
| INIT_LIST_HEAD(&sp->so_delegations); |
| rpc_init_wait_queue(&sp->so_sequence.wait, "Seqid_waitqueue"); |
| sp->so_seqid.sequence = &sp->so_sequence; |
| spin_lock_init(&sp->so_sequence.lock); |
| INIT_LIST_HEAD(&sp->so_sequence.list); |
| atomic_set(&sp->so_count, 1); |
| return sp; |
| } |
| |
| void |
| nfs4_drop_state_owner(struct nfs4_state_owner *sp) |
| { |
| if (!RB_EMPTY_NODE(&sp->so_client_node)) { |
| struct nfs_client *clp = sp->so_client; |
| |
| spin_lock(&clp->cl_lock); |
| rb_erase(&sp->so_client_node, &clp->cl_state_owners); |
| RB_CLEAR_NODE(&sp->so_client_node); |
| 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 nfs_client *clp = server->nfs_client; |
| struct nfs4_state_owner *sp, *new; |
| |
| spin_lock(&clp->cl_lock); |
| sp = nfs4_find_state_owner(clp, cred); |
| spin_unlock(&clp->cl_lock); |
| if (sp != NULL) |
| return sp; |
| new = nfs4_alloc_state_owner(); |
| if (new == NULL) |
| return NULL; |
| new->so_client = clp; |
| new->so_cred = cred; |
| spin_lock(&clp->cl_lock); |
| sp = nfs4_insert_state_owner(clp, new); |
| spin_unlock(&clp->cl_lock); |
| if (sp == new) |
| get_rpccred(cred); |
| else |
| kfree(new); |
| return sp; |
| } |
| |
| /* |
| * 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 nfs_client *clp = sp->so_client; |
| struct rpc_cred *cred = sp->so_cred; |
| |
| if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock)) |
| return; |
| nfs4_remove_state_owner(clp, sp); |
| spin_unlock(&clp->cl_lock); |
| put_rpccred(cred); |
| kfree(sp); |
| } |
| |
| static struct nfs4_state * |
| nfs4_alloc_open_state(void) |
| { |
| struct nfs4_state *state; |
| |
| state = kzalloc(sizeof(*state), GFP_KERNEL); |
| if (!state) |
| return NULL; |
| atomic_set(&state->count, 1); |
| INIT_LIST_HEAD(&state->lock_states); |
| spin_lock_init(&state->state_lock); |
| return state; |
| } |
| |
| void |
| nfs4_state_set_mode_locked(struct nfs4_state *state, mode_t mode) |
| { |
| if (state->state == mode) |
| return; |
| /* NB! List reordering - see the reclaim code for why. */ |
| if ((mode & FMODE_WRITE) != (state->state & FMODE_WRITE)) { |
| if (mode & FMODE_WRITE) |
| list_move(&state->open_states, &state->owner->so_states); |
| else |
| list_move_tail(&state->open_states, &state->owner->so_states); |
| } |
| if (mode == 0) |
| list_del_init(&state->inode_states); |
| state->state = mode; |
| } |
| |
| 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->state == 0) |
| continue; |
| if (state->owner == owner) { |
| atomic_inc(&state->count); |
| return state; |
| } |
| } |
| return NULL; |
| } |
| |
| 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(&owner->so_lock); |
| spin_lock(&inode->i_lock); |
| state = __nfs4_find_state_byowner(inode, owner); |
| if (state == NULL && new != NULL) { |
| state = new; |
| 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); |
| /* 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); |
| spin_unlock(&owner->so_lock); |
| } else { |
| spin_unlock(&inode->i_lock); |
| spin_unlock(&owner->so_lock); |
| if (new) |
| nfs4_free_open_state(new); |
| } |
| out: |
| return state; |
| } |
| |
| /* |
| * Beware! Caller must be holding exactly one |
| * reference to clp->cl_sem! |
| */ |
| 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, &owner->so_lock)) |
| return; |
| spin_lock(&inode->i_lock); |
| if (!list_empty(&state->inode_states)) |
| list_del(&state->inode_states); |
| list_del(&state->open_states); |
| spin_unlock(&inode->i_lock); |
| spin_unlock(&owner->so_lock); |
| iput(inode); |
| nfs4_free_open_state(state); |
| nfs4_put_state_owner(owner); |
| } |
| |
| /* |
| * Close the current file. |
| */ |
| void nfs4_close_state(struct path *path, struct nfs4_state *state, mode_t mode) |
| { |
| struct inode *inode = state->inode; |
| struct nfs4_state_owner *owner = state->owner; |
| int oldstate, newstate = 0; |
| |
| atomic_inc(&owner->so_count); |
| /* Protect against nfs4_find_state() */ |
| spin_lock(&owner->so_lock); |
| spin_lock(&inode->i_lock); |
| switch (mode & (FMODE_READ | FMODE_WRITE)) { |
| case FMODE_READ: |
| state->n_rdonly--; |
| break; |
| case FMODE_WRITE: |
| state->n_wronly--; |
| break; |
| case FMODE_READ|FMODE_WRITE: |
| state->n_rdwr--; |
| } |
| oldstate = newstate = state->state; |
| if (state->n_rdwr == 0) { |
| if (state->n_rdonly == 0) |
| newstate &= ~FMODE_READ; |
| if (state->n_wronly == 0) |
| newstate &= ~FMODE_WRITE; |
| } |
| if (test_bit(NFS_DELEGATED_STATE, &state->flags)) { |
| nfs4_state_set_mode_locked(state, newstate); |
| oldstate = newstate; |
| } |
| spin_unlock(&inode->i_lock); |
| spin_unlock(&owner->so_lock); |
| |
| if (oldstate == newstate) { |
| nfs4_put_open_state(state); |
| nfs4_put_state_owner(owner); |
| } else |
| nfs4_do_close(path, state); |
| } |
| |
| /* |
| * 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; |
| } |
| |
| /* |
| * Return a compatible lock_state. If no initialized lock_state structure |
| * exists, return an uninitialized one. |
| * |
| */ |
| static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner) |
| { |
| struct nfs4_lock_state *lsp; |
| struct nfs_client *clp = state->owner->so_client; |
| |
| lsp = kzalloc(sizeof(*lsp), GFP_KERNEL); |
| if (lsp == NULL) |
| return NULL; |
| lsp->ls_seqid.sequence = &state->owner->so_sequence; |
| atomic_set(&lsp->ls_count, 1); |
| lsp->ls_owner = fl_owner; |
| spin_lock(&clp->cl_lock); |
| nfs_alloc_unique_id(&clp->cl_lockowner_id, &lsp->ls_id, 1, 64); |
| spin_unlock(&clp->cl_lock); |
| INIT_LIST_HEAD(&lsp->ls_locks); |
| return lsp; |
| } |
| |
| static void nfs4_free_lock_state(struct nfs4_lock_state *lsp) |
| { |
| struct nfs_client *clp = lsp->ls_state->owner->so_client; |
| |
| spin_lock(&clp->cl_lock); |
| nfs_free_unique_id(&clp->cl_lockowner_id, &lsp->ls_id); |
| spin_unlock(&clp->cl_lock); |
| kfree(lsp); |
| } |
| |
| /* |
| * Return a compatible lock_state. If no initialized lock_state structure |
| * exists, return an uninitialized one. |
| * |
| * The caller must be holding clp->cl_sem |
| */ |
| static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner) |
| { |
| struct nfs4_lock_state *lsp, *new = NULL; |
| |
| for(;;) { |
| spin_lock(&state->state_lock); |
| lsp = __nfs4_find_lock_state(state, owner); |
| if (lsp != NULL) |
| break; |
| if (new != NULL) { |
| new->ls_state = state; |
| list_add(&new->ls_locks, &state->lock_states); |
| set_bit(LK_STATE_IN_USE, &state->flags); |
| lsp = new; |
| new = NULL; |
| break; |
| } |
| spin_unlock(&state->state_lock); |
| new = nfs4_alloc_lock_state(state, owner); |
| if (new == NULL) |
| return NULL; |
| } |
| spin_unlock(&state->state_lock); |
| if (new != NULL) |
| nfs4_free_lock_state(new); |
| return 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) |
| { |
| struct nfs4_state *state; |
| |
| if (lsp == NULL) |
| return; |
| state = lsp->ls_state; |
| if (!atomic_dec_and_lock(&lsp->ls_count, &state->state_lock)) |
| return; |
| list_del(&lsp->ls_locks); |
| if (list_empty(&state->lock_states)) |
| clear_bit(LK_STATE_IN_USE, &state->flags); |
| spin_unlock(&state->state_lock); |
| nfs4_free_lock_state(lsp); |
| } |
| |
| static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src) |
| { |
| struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner; |
| |
| dst->fl_u.nfs4_fl.owner = lsp; |
| atomic_inc(&lsp->ls_count); |
| } |
| |
| static void nfs4_fl_release_lock(struct file_lock *fl) |
| { |
| nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner); |
| } |
| |
| static struct file_lock_operations nfs4_fl_lock_ops = { |
| .fl_copy_lock = nfs4_fl_copy_lock, |
| .fl_release_private = nfs4_fl_release_lock, |
| }; |
| |
| int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl) |
| { |
| struct nfs4_lock_state *lsp; |
| |
| if (fl->fl_ops != NULL) |
| return 0; |
| lsp = nfs4_get_lock_state(state, fl->fl_owner); |
| if (lsp == NULL) |
| return -ENOMEM; |
| fl->fl_u.nfs4_fl.owner = lsp; |
| fl->fl_ops = &nfs4_fl_lock_ops; |
| return 0; |
| } |
| |
| /* |
| * 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) |
| { |
| struct nfs4_lock_state *lsp; |
| |
| memcpy(dst, &state->stateid, sizeof(*dst)); |
| if (test_bit(LK_STATE_IN_USE, &state->flags) == 0) |
| return; |
| |
| spin_lock(&state->state_lock); |
| lsp = __nfs4_find_lock_state(state, fl_owner); |
| if (lsp != NULL && (lsp->ls_flags & NFS_LOCK_INITIALIZED) != 0) |
| memcpy(dst, &lsp->ls_stateid, sizeof(*dst)); |
| spin_unlock(&state->state_lock); |
| nfs4_put_lock_state(lsp); |
| } |
| |
| struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter) |
| { |
| struct rpc_sequence *sequence = counter->sequence; |
| struct nfs_seqid *new; |
| |
| new = kmalloc(sizeof(*new), GFP_KERNEL); |
| if (new != NULL) { |
| new->sequence = counter; |
| spin_lock(&sequence->lock); |
| list_add_tail(&new->list, &sequence->list); |
| spin_unlock(&sequence->lock); |
| } |
| return new; |
| } |
| |
| void nfs_free_seqid(struct nfs_seqid *seqid) |
| { |
| struct rpc_sequence *sequence = seqid->sequence->sequence; |
| |
| spin_lock(&sequence->lock); |
| list_del(&seqid->list); |
| spin_unlock(&sequence->lock); |
| rpc_wake_up(&sequence->wait); |
| kfree(seqid); |
| } |
| |
| /* |
| * 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() |
| */ |
| static void nfs_increment_seqid(int status, struct nfs_seqid *seqid) |
| { |
| switch (status) { |
| case 0: |
| break; |
| case -NFS4ERR_BAD_SEQID: |
| case -NFS4ERR_STALE_CLIENTID: |
| case -NFS4ERR_STALE_STATEID: |
| case -NFS4ERR_BAD_STATEID: |
| case -NFS4ERR_BADXDR: |
| case -NFS4ERR_RESOURCE: |
| case -NFS4ERR_NOFILEHANDLE: |
| /* Non-seqid mutating errors */ |
| return; |
| }; |
| /* |
| * Note: no locking needed as we are guaranteed to be first |
| * on the sequence list |
| */ |
| seqid->sequence->counter++; |
| } |
| |
| void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid) |
| { |
| if (status == -NFS4ERR_BAD_SEQID) { |
| struct nfs4_state_owner *sp = container_of(seqid->sequence, |
| struct nfs4_state_owner, so_seqid); |
| nfs4_drop_state_owner(sp); |
| } |
| nfs_increment_seqid(status, seqid); |
| } |
| |
| /* |
| * Increment the seqid if the LOCK/LOCKU succeeded, or |
| * failed with a seqid incrementing error - |
| * see comments nfs_fs.h:seqid_mutating_error() |
| */ |
| void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid) |
| { |
| nfs_increment_seqid(status, seqid); |
| } |
| |
| int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task) |
| { |
| struct rpc_sequence *sequence = seqid->sequence->sequence; |
| int status = 0; |
| |
| if (sequence->list.next == &seqid->list) |
| goto out; |
| spin_lock(&sequence->lock); |
| if (sequence->list.next != &seqid->list) { |
| rpc_sleep_on(&sequence->wait, task, NULL, NULL); |
| status = -EAGAIN; |
| } |
| spin_unlock(&sequence->lock); |
| out: |
| return status; |
| } |
| |
| static int reclaimer(void *); |
| |
| static inline void nfs4_clear_recover_bit(struct nfs_client *clp) |
| { |
| smp_mb__before_clear_bit(); |
| clear_bit(NFS4CLNT_STATE_RECOVER, &clp->cl_state); |
| smp_mb__after_clear_bit(); |
| wake_up_bit(&clp->cl_state, NFS4CLNT_STATE_RECOVER); |
| rpc_wake_up(&clp->cl_rpcwaitq); |
| } |
| |
| /* |
| * State recovery routine |
| */ |
| static void nfs4_recover_state(struct nfs_client *clp) |
| { |
| struct task_struct *task; |
| |
| __module_get(THIS_MODULE); |
| atomic_inc(&clp->cl_count); |
| task = kthread_run(reclaimer, clp, "%u.%u.%u.%u-reclaim", |
| NIPQUAD(clp->cl_addr.sin_addr)); |
| if (!IS_ERR(task)) |
| return; |
| nfs4_clear_recover_bit(clp); |
| nfs_put_client(clp); |
| module_put(THIS_MODULE); |
| } |
| |
| /* |
| * Schedule a state recovery attempt |
| */ |
| void nfs4_schedule_state_recovery(struct nfs_client *clp) |
| { |
| if (!clp) |
| return; |
| if (test_and_set_bit(NFS4CLNT_STATE_RECOVER, &clp->cl_state) == 0) |
| nfs4_recover_state(clp); |
| } |
| |
| 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|FL_FLOCK))) |
| 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_pid, 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); |
| 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 void nfs4_state_mark_reclaim(struct nfs_client *clp) |
| { |
| struct nfs4_state_owner *sp; |
| struct rb_node *pos; |
| struct nfs4_state *state; |
| struct nfs4_lock_state *lock; |
| |
| /* 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); |
| sp->so_seqid.counter = 0; |
| sp->so_seqid.flags = 0; |
| spin_lock(&sp->so_lock); |
| list_for_each_entry(state, &sp->so_states, open_states) { |
| list_for_each_entry(lock, &state->lock_states, ls_locks) { |
| lock->ls_seqid.counter = 0; |
| lock->ls_seqid.flags = 0; |
| lock->ls_flags &= ~NFS_LOCK_INITIALIZED; |
| } |
| } |
| spin_unlock(&sp->so_lock); |
| } |
| } |
| |
| static int reclaimer(void *ptr) |
| { |
| struct nfs_client *clp = ptr; |
| struct nfs4_state_owner *sp; |
| struct rb_node *pos; |
| struct nfs4_state_recovery_ops *ops; |
| struct rpc_cred *cred; |
| int status = 0; |
| |
| allow_signal(SIGKILL); |
| |
| /* 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: |
| ops = &nfs4_network_partition_recovery_ops; |
| /* Are there any open files on this volume? */ |
| cred = nfs4_get_renew_cred(clp); |
| if (cred != NULL) { |
| /* Yes there are: try to renew the old lease */ |
| status = nfs4_proc_renew(clp, cred); |
| switch (status) { |
| case 0: |
| case -NFS4ERR_CB_PATH_DOWN: |
| put_rpccred(cred); |
| goto out; |
| case -NFS4ERR_STALE_CLIENTID: |
| case -NFS4ERR_LEASE_MOVED: |
| ops = &nfs4_reboot_recovery_ops; |
| } |
| } else { |
| /* "reboot" to ensure we clear all state on the server */ |
| clp->cl_boot_time = CURRENT_TIME; |
| cred = nfs4_get_setclientid_cred(clp); |
| } |
| /* We're going to have to re-establish a clientid */ |
| nfs4_state_mark_reclaim(clp); |
| status = -ENOENT; |
| if (cred != NULL) { |
| status = nfs4_init_client(clp, cred); |
| put_rpccred(cred); |
| } |
| 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 */ |
| 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); |
| 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: |
| up_write(&clp->cl_sem); |
| unlock_kernel(); |
| if (status == -NFS4ERR_CB_PATH_DOWN) |
| nfs_handle_cb_pathdown(clp); |
| nfs4_clear_recover_bit(clp); |
| nfs_put_client(clp); |
| module_put_and_exit(0); |
| 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.sin_addr), -status); |
| set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state); |
| goto out; |
| } |
| |
| /* |
| * Local variables: |
| * c-basic-offset: 8 |
| * End: |
| */ |