diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /fs/nfs/nfs4state.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/nfs/nfs4state.c')
-rw-r--r-- | fs/nfs/nfs4state.c | 2768 |
1 files changed, 2768 insertions, 0 deletions
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c new file mode 100644 index 000000000..afb617a4a --- /dev/null +++ b/fs/nfs/nfs4state.c @@ -0,0 +1,2768 @@ +/* + * 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/kernel.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/nfs_fs.h> +#include <linux/kthread.h> +#include <linux/module.h> +#include <linux/random.h> +#include <linux/ratelimit.h> +#include <linux/workqueue.h> +#include <linux/bitops.h> +#include <linux/jiffies.h> +#include <linux/sched/mm.h> + +#include <linux/sunrpc/clnt.h> + +#include "nfs4_fs.h" +#include "callback.h" +#include "delegation.h" +#include "internal.h" +#include "nfs4idmap.h" +#include "nfs4session.h" +#include "pnfs.h" +#include "netns.h" +#include "nfs4trace.h" + +#define NFSDBG_FACILITY NFSDBG_STATE + +#define OPENOWNER_POOL_SIZE 8 + +static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp); + +const nfs4_stateid zero_stateid = { + { .data = { 0 } }, + .type = NFS4_SPECIAL_STATEID_TYPE, +}; +const nfs4_stateid invalid_stateid = { + { + /* Funky initialiser keeps older gcc versions happy */ + .data = { 0xff, 0xff, 0xff, 0xff, 0 }, + }, + .type = NFS4_INVALID_STATEID_TYPE, +}; + +const nfs4_stateid current_stateid = { + { + /* Funky initialiser keeps older gcc versions happy */ + .data = { 0x0, 0x0, 0x0, 0x1, 0 }, + }, + .type = NFS4_SPECIAL_STATEID_TYPE, +}; + +static DEFINE_MUTEX(nfs_clid_init_mutex); + +static int nfs4_setup_state_renewal(struct nfs_client *clp) +{ + int status; + struct nfs_fsinfo fsinfo; + + if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) { + nfs4_schedule_state_renewal(clp); + return 0; + } + + status = nfs4_proc_get_lease_time(clp, &fsinfo); + if (status == 0) { + nfs4_set_lease_period(clp, fsinfo.lease_time * HZ); + nfs4_schedule_state_renewal(clp); + } + + return status; +} + +int nfs4_init_clientid(struct nfs_client *clp, const struct cred *cred) +{ + struct nfs4_setclientid_res clid = { + .clientid = clp->cl_clientid, + .confirm = clp->cl_confirm, + }; + unsigned short port; + int status; + struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id); + + if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state)) + goto do_confirm; + port = nn->nfs_callback_tcpport; + if (clp->cl_addr.ss_family == AF_INET6) + port = nn->nfs_callback_tcpport6; + + status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid); + if (status != 0) + goto out; + clp->cl_clientid = clid.clientid; + clp->cl_confirm = clid.confirm; + set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); +do_confirm: + status = nfs4_proc_setclientid_confirm(clp, &clid, cred); + if (status != 0) + goto out; + clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); + nfs4_setup_state_renewal(clp); +out: + return status; +} + +/** + * nfs40_discover_server_trunking - Detect server IP address trunking (mv0) + * + * @clp: nfs_client under test + * @result: OUT: found nfs_client, or clp + * @cred: credential to use for trunking test + * + * Returns zero, a negative errno, or a negative NFS4ERR status. + * If zero is returned, an nfs_client pointer is planted in + * "result". + * + * Note: The returned client may not yet be marked ready. + */ +int nfs40_discover_server_trunking(struct nfs_client *clp, + struct nfs_client **result, + const struct cred *cred) +{ + struct nfs4_setclientid_res clid = { + .clientid = clp->cl_clientid, + .confirm = clp->cl_confirm, + }; + struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id); + unsigned short port; + int status; + + port = nn->nfs_callback_tcpport; + if (clp->cl_addr.ss_family == AF_INET6) + port = nn->nfs_callback_tcpport6; + + status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid); + if (status != 0) + goto out; + clp->cl_clientid = clid.clientid; + clp->cl_confirm = clid.confirm; + + status = nfs40_walk_client_list(clp, result, cred); + if (status == 0) { + /* Sustain the lease, even if it's empty. If the clientid4 + * goes stale it's of no use for trunking discovery. */ + nfs4_schedule_state_renewal(*result); + + /* If the client state need to recover, do it. */ + if (clp->cl_state) + nfs4_schedule_state_manager(clp); + } +out: + return status; +} + +const struct cred *nfs4_get_machine_cred(struct nfs_client *clp) +{ + return get_cred(rpc_machine_cred()); +} + +static void nfs4_root_machine_cred(struct nfs_client *clp) +{ + + /* Force root creds instead of machine */ + clp->cl_principal = NULL; + clp->cl_rpcclient->cl_principal = NULL; +} + +static const struct cred * +nfs4_get_renew_cred_server_locked(struct nfs_server *server) +{ + const struct cred *cred = NULL; + struct nfs4_state_owner *sp; + struct rb_node *pos; + + 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_cred(sp->so_cred); + break; + } + return cred; +} + +/** + * nfs4_get_renew_cred - 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. + */ +const struct cred *nfs4_get_renew_cred(struct nfs_client *clp) +{ + const struct cred *cred = NULL; + struct nfs_server *server; + + /* Use machine credentials if available */ + cred = nfs4_get_machine_cred(clp); + if (cred != NULL) + goto out; + + spin_lock(&clp->cl_lock); + 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(); + spin_unlock(&clp->cl_lock); + +out: + return cred; +} + +static void nfs4_end_drain_slot_table(struct nfs4_slot_table *tbl) +{ + if (test_and_clear_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) { + spin_lock(&tbl->slot_tbl_lock); + nfs41_wake_slot_table(tbl); + spin_unlock(&tbl->slot_tbl_lock); + } +} + +static void nfs4_end_drain_session(struct nfs_client *clp) +{ + struct nfs4_session *ses = clp->cl_session; + + if (clp->cl_slot_tbl) { + nfs4_end_drain_slot_table(clp->cl_slot_tbl); + return; + } + + if (ses != NULL) { + nfs4_end_drain_slot_table(&ses->bc_slot_table); + nfs4_end_drain_slot_table(&ses->fc_slot_table); + } +} + +static int nfs4_drain_slot_tbl(struct nfs4_slot_table *tbl) +{ + set_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state); + spin_lock(&tbl->slot_tbl_lock); + if (tbl->highest_used_slotid != NFS4_NO_SLOT) { + reinit_completion(&tbl->complete); + spin_unlock(&tbl->slot_tbl_lock); + return wait_for_completion_interruptible(&tbl->complete); + } + spin_unlock(&tbl->slot_tbl_lock); + return 0; +} + +static int nfs4_begin_drain_session(struct nfs_client *clp) +{ + struct nfs4_session *ses = clp->cl_session; + int ret; + + if (clp->cl_slot_tbl) + return nfs4_drain_slot_tbl(clp->cl_slot_tbl); + + /* back channel */ + ret = nfs4_drain_slot_tbl(&ses->bc_slot_table); + if (ret) + return ret; + /* fore channel */ + return nfs4_drain_slot_tbl(&ses->fc_slot_table); +} + +#if defined(CONFIG_NFS_V4_1) + +static void nfs41_finish_session_reset(struct nfs_client *clp) +{ + clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); + clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state); + /* create_session negotiated new slot table */ + clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state); + nfs4_setup_state_renewal(clp); +} + +int nfs41_init_clientid(struct nfs_client *clp, const struct cred *cred) +{ + int status; + + if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state)) + goto do_confirm; + status = nfs4_proc_exchange_id(clp, cred); + if (status != 0) + goto out; + set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); +do_confirm: + status = nfs4_proc_create_session(clp, cred); + if (status != 0) + goto out; + if (!(clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R)) + nfs4_state_start_reclaim_reboot(clp); + nfs41_finish_session_reset(clp); + nfs_mark_client_ready(clp, NFS_CS_READY); +out: + return status; +} + +/** + * nfs41_discover_server_trunking - Detect server IP address trunking (mv1) + * + * @clp: nfs_client under test + * @result: OUT: found nfs_client, or clp + * @cred: credential to use for trunking test + * + * Returns NFS4_OK, a negative errno, or a negative NFS4ERR status. + * If NFS4_OK is returned, an nfs_client pointer is planted in + * "result". + * + * Note: The returned client may not yet be marked ready. + */ +int nfs41_discover_server_trunking(struct nfs_client *clp, + struct nfs_client **result, + const struct cred *cred) +{ + int status; + + status = nfs4_proc_exchange_id(clp, cred); + if (status != NFS4_OK) + return status; + + status = nfs41_walk_client_list(clp, result, cred); + if (status < 0) + return status; + if (clp != *result) + return 0; + + /* + * Purge state if the client id was established in a prior + * instance and the client id could not have arrived on the + * server via Transparent State Migration. + */ + if (clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R) { + if (!test_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags)) + set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state); + else + set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); + } + nfs4_schedule_state_manager(clp); + status = nfs_wait_client_init_complete(clp); + if (status < 0) + nfs_put_client(clp); + return status; +} + +#endif /* CONFIG_NFS_V4_1 */ + +/** + * nfs4_get_clid_cred - Acquire credential for a setclientid operation + * @clp: client state handle + * + * Returns a cred with reference count bumped, or NULL. + */ +const struct cred *nfs4_get_clid_cred(struct nfs_client *clp) +{ + const struct cred *cred; + + cred = nfs4_get_machine_cred(clp); + return cred; +} + +static struct nfs4_state_owner * +nfs4_find_state_owner_locked(struct nfs_server *server, const struct cred *cred) +{ + struct rb_node **p = &server->state_owners.rb_node, + *parent = NULL; + struct nfs4_state_owner *sp; + int cmp; + + while (*p != NULL) { + parent = *p; + sp = rb_entry(parent, struct nfs4_state_owner, so_server_node); + cmp = cred_fscmp(cred, sp->so_cred); + + if (cmp < 0) + p = &parent->rb_left; + else if (cmp > 0) + p = &parent->rb_right; + else { + if (!list_empty(&sp->so_lru)) + list_del_init(&sp->so_lru); + atomic_inc(&sp->so_count); + return sp; + } + } + return NULL; +} + +static struct nfs4_state_owner * +nfs4_insert_state_owner_locked(struct nfs4_state_owner *new) +{ + struct nfs_server *server = new->so_server; + struct rb_node **p = &server->state_owners.rb_node, + *parent = NULL; + struct nfs4_state_owner *sp; + int cmp; + + while (*p != NULL) { + parent = *p; + sp = rb_entry(parent, struct nfs4_state_owner, so_server_node); + cmp = cred_fscmp(new->so_cred, sp->so_cred); + + if (cmp < 0) + p = &parent->rb_left; + else if (cmp > 0) + p = &parent->rb_right; + else { + if (!list_empty(&sp->so_lru)) + list_del_init(&sp->so_lru); + atomic_inc(&sp->so_count); + return sp; + } + } + 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_locked(struct nfs4_state_owner *sp) +{ + struct nfs_server *server = sp->so_server; + + if (!RB_EMPTY_NODE(&sp->so_server_node)) + rb_erase(&sp->so_server_node, &server->state_owners); +} + +static void +nfs4_init_seqid_counter(struct nfs_seqid_counter *sc) +{ + sc->create_time = ktime_get(); + sc->flags = 0; + sc->counter = 0; + spin_lock_init(&sc->lock); + INIT_LIST_HEAD(&sc->list); + rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue"); +} + +static void +nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc) +{ + rpc_destroy_wait_queue(&sc->wait); +} + +/* + * 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(struct nfs_server *server, + const struct cred *cred, + gfp_t gfp_flags) +{ + struct nfs4_state_owner *sp; + + sp = kzalloc(sizeof(*sp), gfp_flags); + if (!sp) + return NULL; + sp->so_seqid.owner_id = ida_simple_get(&server->openowner_id, 0, 0, + gfp_flags); + if (sp->so_seqid.owner_id < 0) { + kfree(sp); + return NULL; + } + sp->so_server = server; + sp->so_cred = get_cred(cred); + spin_lock_init(&sp->so_lock); + INIT_LIST_HEAD(&sp->so_states); + nfs4_init_seqid_counter(&sp->so_seqid); + atomic_set(&sp->so_count, 1); + INIT_LIST_HEAD(&sp->so_lru); + seqcount_spinlock_init(&sp->so_reclaim_seqcount, &sp->so_lock); + mutex_init(&sp->so_delegreturn_mutex); + return sp; +} + +static void +nfs4_reset_state_owner(struct nfs4_state_owner *sp) +{ + /* This state_owner is no longer usable, but must + * remain in place so that state recovery can find it + * and the opens associated with it. + * It may also be used for new 'open' request to + * return a delegation to the server. + * So update the 'create_time' so that it looks like + * a new state_owner. This will cause the server to + * request an OPEN_CONFIRM to start a new sequence. + */ + sp->so_seqid.create_time = ktime_get(); +} + +static void nfs4_free_state_owner(struct nfs4_state_owner *sp) +{ + nfs4_destroy_seqid_counter(&sp->so_seqid); + put_cred(sp->so_cred); + ida_simple_remove(&sp->so_server->openowner_id, sp->so_seqid.owner_id); + kfree(sp); +} + +static void nfs4_gc_state_owners(struct nfs_server *server) +{ + struct nfs_client *clp = server->nfs_client; + struct nfs4_state_owner *sp, *tmp; + unsigned long time_min, time_max; + LIST_HEAD(doomed); + + spin_lock(&clp->cl_lock); + time_max = jiffies; + time_min = (long)time_max - (long)clp->cl_lease_time; + list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) { + /* NB: LRU is sorted so that oldest is at the head */ + if (time_in_range(sp->so_expires, time_min, time_max)) + break; + list_move(&sp->so_lru, &doomed); + nfs4_remove_state_owner_locked(sp); + } + spin_unlock(&clp->cl_lock); + + list_for_each_entry_safe(sp, tmp, &doomed, so_lru) { + list_del(&sp->so_lru); + nfs4_free_state_owner(sp); + } +} + +/** + * nfs4_get_state_owner - Look up a state owner given a credential + * @server: nfs_server to search + * @cred: RPC credential to match + * @gfp_flags: allocation mode + * + * Returns a pointer to an instantiated nfs4_state_owner struct, or NULL. + */ +struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, + const struct cred *cred, + gfp_t gfp_flags) +{ + struct nfs_client *clp = server->nfs_client; + struct nfs4_state_owner *sp, *new; + + spin_lock(&clp->cl_lock); + sp = nfs4_find_state_owner_locked(server, cred); + spin_unlock(&clp->cl_lock); + if (sp != NULL) + goto out; + new = nfs4_alloc_state_owner(server, cred, gfp_flags); + if (new == NULL) + goto out; + spin_lock(&clp->cl_lock); + sp = nfs4_insert_state_owner_locked(new); + spin_unlock(&clp->cl_lock); + if (sp != new) + nfs4_free_state_owner(new); +out: + nfs4_gc_state_owners(server); + return sp; +} + +/** + * nfs4_put_state_owner - Release a nfs4_state_owner + * @sp: state owner data to release + * + * Note that we keep released state owners on an LRU + * list. + * This caches valid state owners so that they can be + * reused, to avoid the OPEN_CONFIRM on minor version 0. + * It also pins the uniquifier of dropped state owners for + * a while, to ensure that those state owner names are + * never reused. + */ +void nfs4_put_state_owner(struct nfs4_state_owner *sp) +{ + struct nfs_server *server = sp->so_server; + struct nfs_client *clp = server->nfs_client; + + if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock)) + return; + + sp->so_expires = jiffies; + list_add_tail(&sp->so_lru, &server->state_owners_lru); + spin_unlock(&clp->cl_lock); +} + +/** + * nfs4_purge_state_owners - Release all cached state owners + * @server: nfs_server with cached state owners to release + * @head: resulting list of state owners + * + * Called at umount time. Remaining state owners will be on + * the LRU with ref count of zero. + * Note that the state owners are not freed, but are added + * to the list @head, which can later be used as an argument + * to nfs4_free_state_owners. + */ +void nfs4_purge_state_owners(struct nfs_server *server, struct list_head *head) +{ + struct nfs_client *clp = server->nfs_client; + struct nfs4_state_owner *sp, *tmp; + + spin_lock(&clp->cl_lock); + list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) { + list_move(&sp->so_lru, head); + nfs4_remove_state_owner_locked(sp); + } + spin_unlock(&clp->cl_lock); +} + +/** + * nfs4_purge_state_owners - Release all cached state owners + * @head: resulting list of state owners + * + * Frees a list of state owners that was generated by + * nfs4_purge_state_owners + */ +void nfs4_free_state_owners(struct list_head *head) +{ + struct nfs4_state_owner *sp, *tmp; + + list_for_each_entry_safe(sp, tmp, head, so_lru) { + list_del(&sp->so_lru); + nfs4_free_state_owner(sp); + } +} + +static struct nfs4_state * +nfs4_alloc_open_state(void) +{ + struct nfs4_state *state; + + state = kzalloc(sizeof(*state), GFP_NOFS); + if (!state) + return NULL; + refcount_set(&state->count, 1); + INIT_LIST_HEAD(&state->lock_states); + spin_lock_init(&state->state_lock); + seqlock_init(&state->seqlock); + init_waitqueue_head(&state->waitq); + return state; +} + +void +nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode) +{ + if (state->state == fmode) + return; + /* NB! List reordering - see the reclaim code for why. */ + if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) { + if (fmode & FMODE_WRITE) + list_move(&state->open_states, &state->owner->so_states); + else + list_move_tail(&state->open_states, &state->owner->so_states); + } + state->state = fmode; +} + +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_rcu(state, &nfsi->open_states, inode_states) { + if (state->owner != owner) + continue; + if (!nfs4_valid_open_stateid(state)) + continue; + if (refcount_inc_not_zero(&state->count)) + return state; + } + return NULL; +} + +static void +nfs4_free_open_state(struct nfs4_state *state) +{ + kfree_rcu(state, rcu_head); +} + +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); + + rcu_read_lock(); + state = __nfs4_find_state_byowner(inode, owner); + rcu_read_unlock(); + 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); + ihold(inode); + state->inode = inode; + list_add_rcu(&state->inode_states, &nfsi->open_states); + 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; +} + +void nfs4_put_open_state(struct nfs4_state *state) +{ + struct inode *inode = state->inode; + struct nfs4_state_owner *owner = state->owner; + + if (!refcount_dec_and_lock(&state->count, &owner->so_lock)) + return; + spin_lock(&inode->i_lock); + list_del_rcu(&state->inode_states); + list_del(&state->open_states); + spin_unlock(&inode->i_lock); + spin_unlock(&owner->so_lock); + nfs4_inode_return_delegation_on_close(inode); + iput(inode); + nfs4_free_open_state(state); + nfs4_put_state_owner(owner); +} + +/* + * Close the current file. + */ +static void __nfs4_close(struct nfs4_state *state, + fmode_t fmode, gfp_t gfp_mask, int wait) +{ + struct nfs4_state_owner *owner = state->owner; + int call_close = 0; + fmode_t newstate; + + atomic_inc(&owner->so_count); + /* Protect against nfs4_find_state() */ + spin_lock(&owner->so_lock); + switch (fmode & (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--; + } + newstate = FMODE_READ|FMODE_WRITE; + if (state->n_rdwr == 0) { + if (state->n_rdonly == 0) { + newstate &= ~FMODE_READ; + call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags); + call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags); + } + if (state->n_wronly == 0) { + newstate &= ~FMODE_WRITE; + call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags); + call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags); + } + if (newstate == 0) + clear_bit(NFS_DELEGATED_STATE, &state->flags); + } + nfs4_state_set_mode_locked(state, newstate); + spin_unlock(&owner->so_lock); + + if (!call_close) { + nfs4_put_open_state(state); + nfs4_put_state_owner(owner); + } else + nfs4_do_close(state, gfp_mask, wait); +} + +void nfs4_close_state(struct nfs4_state *state, fmode_t fmode) +{ + __nfs4_close(state, fmode, GFP_NOFS, 0); +} + +void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode) +{ + __nfs4_close(state, fmode, GFP_KERNEL, 1); +} + +/* + * Search the state->lock_states for an existing lock_owner + * that is compatible with either of the given owners. + * If the second is non-zero, then the first refers to a Posix-lock + * owner (current->files) and the second refers to a flock/OFD + * owner (struct file*). In that case, prefer a match for the first + * owner. + * If both sorts of locks are held on the one file we cannot know + * which stateid was intended to be used, so a "correct" choice cannot + * be made. Failing that, a "consistent" choice is preferable. The + * consistent choice we make is to prefer the first owner, that of a + * Posix lock. + */ +static struct nfs4_lock_state * +__nfs4_find_lock_state(struct nfs4_state *state, + fl_owner_t fl_owner, fl_owner_t fl_owner2) +{ + struct nfs4_lock_state *pos, *ret = NULL; + list_for_each_entry(pos, &state->lock_states, ls_locks) { + if (pos->ls_owner == fl_owner) { + ret = pos; + break; + } + if (pos->ls_owner == fl_owner2) + ret = pos; + } + if (ret) + refcount_inc(&ret->ls_count); + return ret; +} + +/* + * 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_server *server = state->owner->so_server; + + lsp = kzalloc(sizeof(*lsp), GFP_NOFS); + if (lsp == NULL) + return NULL; + nfs4_init_seqid_counter(&lsp->ls_seqid); + refcount_set(&lsp->ls_count, 1); + lsp->ls_state = state; + lsp->ls_owner = fl_owner; + lsp->ls_seqid.owner_id = ida_simple_get(&server->lockowner_id, 0, 0, GFP_NOFS); + if (lsp->ls_seqid.owner_id < 0) + goto out_free; + INIT_LIST_HEAD(&lsp->ls_locks); + return lsp; +out_free: + kfree(lsp); + return NULL; +} + +void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp) +{ + ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id); + nfs4_destroy_seqid_counter(&lsp->ls_seqid); + kfree(lsp); +} + +/* + * Return a compatible lock_state. If no initialized lock_state structure + * exists, return an uninitialized one. + * + */ +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, NULL); + if (lsp != NULL) + break; + if (new != NULL) { + 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(state->owner->so_server, 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 nfs_server *server; + struct nfs4_state *state; + + if (lsp == NULL) + return; + state = lsp->ls_state; + if (!refcount_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); + server = state->owner->so_server; + if (test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags)) { + struct nfs_client *clp = server->nfs_client; + + clp->cl_mvops->free_lock_state(server, lsp); + } else + nfs4_free_lock_state(server, 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; + refcount_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 const 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; +} + +static int nfs4_copy_lock_stateid(nfs4_stateid *dst, + struct nfs4_state *state, + const struct nfs_lock_context *l_ctx) +{ + struct nfs4_lock_state *lsp; + fl_owner_t fl_owner, fl_flock_owner; + int ret = -ENOENT; + + if (l_ctx == NULL) + goto out; + + if (test_bit(LK_STATE_IN_USE, &state->flags) == 0) + goto out; + + fl_owner = l_ctx->lockowner; + fl_flock_owner = l_ctx->open_context->flock_owner; + + spin_lock(&state->state_lock); + lsp = __nfs4_find_lock_state(state, fl_owner, fl_flock_owner); + if (lsp && test_bit(NFS_LOCK_LOST, &lsp->ls_flags)) + ret = -EIO; + else if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) { + nfs4_stateid_copy(dst, &lsp->ls_stateid); + ret = 0; + } + spin_unlock(&state->state_lock); + nfs4_put_lock_state(lsp); +out: + return ret; +} + +bool nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state) +{ + bool ret; + const nfs4_stateid *src; + int seq; + + do { + ret = false; + src = &zero_stateid; + seq = read_seqbegin(&state->seqlock); + if (test_bit(NFS_OPEN_STATE, &state->flags)) { + src = &state->open_stateid; + ret = true; + } + nfs4_stateid_copy(dst, src); + } while (read_seqretry(&state->seqlock, seq)); + return ret; +} + +/* + * Byte-range lock aware utility to initialize the stateid of read/write + * requests. + */ +int nfs4_select_rw_stateid(struct nfs4_state *state, + fmode_t fmode, const struct nfs_lock_context *l_ctx, + nfs4_stateid *dst, const struct cred **cred) +{ + int ret; + + if (!nfs4_valid_open_stateid(state)) + return -EIO; + if (cred != NULL) + *cred = NULL; + ret = nfs4_copy_lock_stateid(dst, state, l_ctx); + if (ret == -EIO) + /* A lost lock - don't even consider delegations */ + goto out; + /* returns true if delegation stateid found and copied */ + if (nfs4_copy_delegation_stateid(state->inode, fmode, dst, cred)) { + ret = 0; + goto out; + } + if (ret != -ENOENT) + /* nfs4_copy_delegation_stateid() didn't over-write + * dst, so it still has the lock stateid which we now + * choose to use. + */ + goto out; + ret = nfs4_copy_open_stateid(dst, state) ? 0 : -EAGAIN; +out: + if (nfs_server_capable(state->inode, NFS_CAP_STATEID_NFSV41)) + dst->seqid = 0; + return ret; +} + +struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask) +{ + struct nfs_seqid *new; + + new = kmalloc(sizeof(*new), gfp_mask); + if (new == NULL) + return ERR_PTR(-ENOMEM); + new->sequence = counter; + INIT_LIST_HEAD(&new->list); + new->task = NULL; + return new; +} + +void nfs_release_seqid(struct nfs_seqid *seqid) +{ + struct nfs_seqid_counter *sequence; + + if (seqid == NULL || list_empty(&seqid->list)) + return; + sequence = seqid->sequence; + spin_lock(&sequence->lock); + list_del_init(&seqid->list); + if (!list_empty(&sequence->list)) { + struct nfs_seqid *next; + + next = list_first_entry(&sequence->list, + struct nfs_seqid, list); + rpc_wake_up_queued_task(&sequence->wait, next->task); + } + spin_unlock(&sequence->lock); +} + +void nfs_free_seqid(struct nfs_seqid *seqid) +{ + nfs_release_seqid(seqid); + kfree(seqid); +} + +/* + * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or + * failed with a seqid incrementing error - + * see comments nfs4.h:seqid_mutating_error() + */ +static void nfs_increment_seqid(int status, struct nfs_seqid *seqid) +{ + switch (status) { + case 0: + break; + case -NFS4ERR_BAD_SEQID: + if (seqid->sequence->flags & NFS_SEQID_CONFIRMED) + return; + pr_warn_ratelimited("NFS: v4 server returned a bad" + " sequence-id error on an" + " unconfirmed sequence %p!\n", + seqid->sequence); + case -NFS4ERR_STALE_CLIENTID: + case -NFS4ERR_STALE_STATEID: + case -NFS4ERR_BAD_STATEID: + case -NFS4ERR_BADXDR: + case -NFS4ERR_RESOURCE: + case -NFS4ERR_NOFILEHANDLE: + case -NFS4ERR_MOVED: + /* 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) +{ + struct nfs4_state_owner *sp; + + if (seqid == NULL) + return; + + sp = container_of(seqid->sequence, struct nfs4_state_owner, so_seqid); + if (status == -NFS4ERR_BAD_SEQID) + nfs4_reset_state_owner(sp); + if (!nfs4_has_session(sp->so_server->nfs_client)) + nfs_increment_seqid(status, seqid); +} + +/* + * Increment the seqid if the LOCK/LOCKU succeeded, or + * failed with a seqid incrementing error - + * see comments nfs4.h:seqid_mutating_error() + */ +void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid) +{ + if (seqid != NULL) + nfs_increment_seqid(status, seqid); +} + +int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task) +{ + struct nfs_seqid_counter *sequence; + int status = 0; + + if (seqid == NULL) + goto out; + sequence = seqid->sequence; + spin_lock(&sequence->lock); + seqid->task = task; + if (list_empty(&seqid->list)) + list_add_tail(&seqid->list, &sequence->list); + if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid) + goto unlock; + rpc_sleep_on(&sequence->wait, task, NULL); + status = -EAGAIN; +unlock: + spin_unlock(&sequence->lock); +out: + return status; +} + +static int nfs4_run_state_manager(void *); + +static void nfs4_clear_state_manager_bit(struct nfs_client *clp) +{ + smp_mb__before_atomic(); + clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state); + smp_mb__after_atomic(); + wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING); + rpc_wake_up(&clp->cl_rpcwaitq); +} + +/* + * Schedule the nfs_client asynchronous state management routine + */ +void nfs4_schedule_state_manager(struct nfs_client *clp) +{ + struct task_struct *task; + char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1]; + struct rpc_clnt *clnt = clp->cl_rpcclient; + bool swapon = false; + + set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state); + + if (atomic_read(&clnt->cl_swapper)) { + swapon = !test_and_set_bit(NFS4CLNT_MANAGER_AVAILABLE, + &clp->cl_state); + if (!swapon) { + wake_up_var(&clp->cl_state); + return; + } + } + + if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0) + return; + + __module_get(THIS_MODULE); + refcount_inc(&clp->cl_count); + + /* The rcu_read_lock() is not strictly necessary, as the state + * manager is the only thread that ever changes the rpc_xprt + * after it's initialized. At this point, we're single threaded. */ + rcu_read_lock(); + snprintf(buf, sizeof(buf), "%s-manager", + rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR)); + rcu_read_unlock(); + task = kthread_run(nfs4_run_state_manager, clp, "%s", buf); + if (IS_ERR(task)) { + printk(KERN_ERR "%s: kthread_run: %ld\n", + __func__, PTR_ERR(task)); + if (!nfs_client_init_is_complete(clp)) + nfs_mark_client_ready(clp, PTR_ERR(task)); + if (swapon) + clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state); + nfs4_clear_state_manager_bit(clp); + nfs_put_client(clp); + module_put(THIS_MODULE); + } +} + +/* + * Schedule a lease recovery attempt + */ +void nfs4_schedule_lease_recovery(struct nfs_client *clp) +{ + if (!clp) + return; + if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) + set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state); + dprintk("%s: scheduling lease recovery for server %s\n", __func__, + clp->cl_hostname); + nfs4_schedule_state_manager(clp); +} +EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery); + +/** + * nfs4_schedule_migration_recovery - trigger migration recovery + * + * @server: FSID that is migrating + * + * Returns zero if recovery has started, otherwise a negative NFS4ERR + * value is returned. + */ +int nfs4_schedule_migration_recovery(const struct nfs_server *server) +{ + struct nfs_client *clp = server->nfs_client; + + if (server->fh_expire_type != NFS4_FH_PERSISTENT) { + pr_err("NFS: volatile file handles not supported (server %s)\n", + clp->cl_hostname); + return -NFS4ERR_IO; + } + + if (test_bit(NFS_MIG_FAILED, &server->mig_status)) + return -NFS4ERR_IO; + + dprintk("%s: scheduling migration recovery for (%llx:%llx) on %s\n", + __func__, + (unsigned long long)server->fsid.major, + (unsigned long long)server->fsid.minor, + clp->cl_hostname); + + set_bit(NFS_MIG_IN_TRANSITION, + &((struct nfs_server *)server)->mig_status); + set_bit(NFS4CLNT_MOVED, &clp->cl_state); + + nfs4_schedule_state_manager(clp); + return 0; +} +EXPORT_SYMBOL_GPL(nfs4_schedule_migration_recovery); + +/** + * nfs4_schedule_lease_moved_recovery - start lease-moved recovery + * + * @clp: server to check for moved leases + * + */ +void nfs4_schedule_lease_moved_recovery(struct nfs_client *clp) +{ + dprintk("%s: scheduling lease-moved recovery for client ID %llx on %s\n", + __func__, clp->cl_clientid, clp->cl_hostname); + + set_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state); + nfs4_schedule_state_manager(clp); +} +EXPORT_SYMBOL_GPL(nfs4_schedule_lease_moved_recovery); + +int nfs4_wait_clnt_recover(struct nfs_client *clp) +{ + int res; + + might_sleep(); + + refcount_inc(&clp->cl_count); + res = wait_on_bit_action(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING, + nfs_wait_bit_killable, TASK_KILLABLE); + if (res) + goto out; + if (clp->cl_cons_state < 0) + res = clp->cl_cons_state; +out: + nfs_put_client(clp); + return res; +} + +int nfs4_client_recover_expired_lease(struct nfs_client *clp) +{ + unsigned int loop; + int ret; + + for (loop = NFS4_MAX_LOOP_ON_RECOVER; loop != 0; loop--) { + ret = nfs4_wait_clnt_recover(clp); + if (ret != 0) + break; + if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) && + !test_bit(NFS4CLNT_CHECK_LEASE,&clp->cl_state)) + break; + nfs4_schedule_state_manager(clp); + ret = -EIO; + } + return ret; +} + +/* + * nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN + * @clp: client to process + * + * Set the NFS4CLNT_LEASE_EXPIRED state in order to force a + * resend of the SETCLIENTID and hence re-establish the + * callback channel. Then return all existing delegations. + */ +static void nfs40_handle_cb_pathdown(struct nfs_client *clp) +{ + set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state); + nfs_expire_all_delegations(clp); + dprintk("%s: handling CB_PATHDOWN recovery for server %s\n", __func__, + clp->cl_hostname); +} + +void nfs4_schedule_path_down_recovery(struct nfs_client *clp) +{ + nfs40_handle_cb_pathdown(clp); + nfs4_schedule_state_manager(clp); +} + +static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state) +{ + + if (!nfs4_valid_open_stateid(state)) + return 0; + set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags); + /* Don't recover state that expired before the reboot */ + if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) { + clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags); + return 0; + } + set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags); + set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state); + return 1; +} + +int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state) +{ + if (!nfs4_valid_open_stateid(state)) + return 0; + set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags); + clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags); + set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags); + set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state); + return 1; +} + +int nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state) +{ + struct nfs_client *clp = server->nfs_client; + + if (!nfs4_state_mark_reclaim_nograce(clp, state)) + return -EBADF; + nfs_inode_find_delegation_state_and_recover(state->inode, + &state->stateid); + dprintk("%s: scheduling stateid recovery for server %s\n", __func__, + clp->cl_hostname); + nfs4_schedule_state_manager(clp); + return 0; +} +EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery); + +static struct nfs4_lock_state * +nfs_state_find_lock_state_by_stateid(struct nfs4_state *state, + const nfs4_stateid *stateid) +{ + struct nfs4_lock_state *pos; + + list_for_each_entry(pos, &state->lock_states, ls_locks) { + if (!test_bit(NFS_LOCK_INITIALIZED, &pos->ls_flags)) + continue; + if (nfs4_stateid_match_or_older(&pos->ls_stateid, stateid)) + return pos; + } + return NULL; +} + +static bool nfs_state_lock_state_matches_stateid(struct nfs4_state *state, + const nfs4_stateid *stateid) +{ + bool found = false; + + if (test_bit(LK_STATE_IN_USE, &state->flags)) { + spin_lock(&state->state_lock); + if (nfs_state_find_lock_state_by_stateid(state, stateid)) + found = true; + spin_unlock(&state->state_lock); + } + return found; +} + +void nfs_inode_find_state_and_recover(struct inode *inode, + const nfs4_stateid *stateid) +{ + struct nfs_client *clp = NFS_SERVER(inode)->nfs_client; + struct nfs_inode *nfsi = NFS_I(inode); + struct nfs_open_context *ctx; + struct nfs4_state *state; + bool found = false; + + rcu_read_lock(); + list_for_each_entry_rcu(ctx, &nfsi->open_files, list) { + state = ctx->state; + if (state == NULL) + continue; + if (nfs4_stateid_match_or_older(&state->stateid, stateid) && + nfs4_state_mark_reclaim_nograce(clp, state)) { + found = true; + continue; + } + if (test_bit(NFS_OPEN_STATE, &state->flags) && + nfs4_stateid_match_or_older(&state->open_stateid, stateid) && + nfs4_state_mark_reclaim_nograce(clp, state)) { + found = true; + continue; + } + if (nfs_state_lock_state_matches_stateid(state, stateid) && + nfs4_state_mark_reclaim_nograce(clp, state)) + found = true; + } + rcu_read_unlock(); + + nfs_inode_find_delegation_state_and_recover(inode, stateid); + if (found) + nfs4_schedule_state_manager(clp); +} + +static void nfs4_state_mark_open_context_bad(struct nfs4_state *state, int err) +{ + struct inode *inode = state->inode; + struct nfs_inode *nfsi = NFS_I(inode); + struct nfs_open_context *ctx; + + rcu_read_lock(); + list_for_each_entry_rcu(ctx, &nfsi->open_files, list) { + if (ctx->state != state) + continue; + set_bit(NFS_CONTEXT_BAD, &ctx->flags); + pr_warn("NFSv4: state recovery failed for open file %pd2, " + "error = %d\n", ctx->dentry, err); + } + rcu_read_unlock(); +} + +static void nfs4_state_mark_recovery_failed(struct nfs4_state *state, int error) +{ + set_bit(NFS_STATE_RECOVERY_FAILED, &state->flags); + nfs4_state_mark_open_context_bad(state, error); +} + + +static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops) +{ + struct inode *inode = state->inode; + struct nfs_inode *nfsi = NFS_I(inode); + struct file_lock *fl; + struct nfs4_lock_state *lsp; + int status = 0; + struct file_lock_context *flctx = inode->i_flctx; + struct list_head *list; + + if (flctx == NULL) + return 0; + + list = &flctx->flc_posix; + + /* Guard against delegation returns and new lock/unlock calls */ + down_write(&nfsi->rwsem); + spin_lock(&flctx->flc_lock); +restart: + list_for_each_entry(fl, list, fl_list) { + if (nfs_file_open_context(fl->fl_file)->state != state) + continue; + spin_unlock(&flctx->flc_lock); + status = ops->recover_lock(state, fl); + switch (status) { + case 0: + break; + case -ETIMEDOUT: + case -ESTALE: + case -NFS4ERR_ADMIN_REVOKED: + case -NFS4ERR_STALE_STATEID: + case -NFS4ERR_BAD_STATEID: + case -NFS4ERR_EXPIRED: + case -NFS4ERR_NO_GRACE: + case -NFS4ERR_STALE_CLIENTID: + case -NFS4ERR_BADSESSION: + case -NFS4ERR_BADSLOT: + case -NFS4ERR_BAD_HIGH_SLOT: + case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION: + goto out; + default: + pr_err("NFS: %s: unhandled error %d\n", + __func__, status); + fallthrough; + case -ENOMEM: + case -NFS4ERR_DENIED: + case -NFS4ERR_RECLAIM_BAD: + case -NFS4ERR_RECLAIM_CONFLICT: + lsp = fl->fl_u.nfs4_fl.owner; + if (lsp) + set_bit(NFS_LOCK_LOST, &lsp->ls_flags); + status = 0; + } + spin_lock(&flctx->flc_lock); + } + if (list == &flctx->flc_posix) { + list = &flctx->flc_flock; + goto restart; + } + spin_unlock(&flctx->flc_lock); +out: + up_write(&nfsi->rwsem); + return status; +} + +#ifdef CONFIG_NFS_V4_2 +static void nfs42_complete_copies(struct nfs4_state_owner *sp, struct nfs4_state *state) +{ + struct nfs4_copy_state *copy; + + if (!test_bit(NFS_CLNT_DST_SSC_COPY_STATE, &state->flags) && + !test_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags)) + return; + + spin_lock(&sp->so_server->nfs_client->cl_lock); + list_for_each_entry(copy, &sp->so_server->ss_copies, copies) { + if ((test_bit(NFS_CLNT_DST_SSC_COPY_STATE, &state->flags) && + !nfs4_stateid_match_other(&state->stateid, + ©->parent_dst_state->stateid))) + continue; + copy->flags = 1; + if (test_and_clear_bit(NFS_CLNT_DST_SSC_COPY_STATE, + &state->flags)) { + clear_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags); + complete(©->completion); + } + } + list_for_each_entry(copy, &sp->so_server->ss_copies, src_copies) { + if ((test_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags) && + !nfs4_stateid_match_other(&state->stateid, + ©->parent_src_state->stateid))) + continue; + copy->flags = 1; + if (test_and_clear_bit(NFS_CLNT_DST_SSC_COPY_STATE, + &state->flags)) + complete(©->completion); + } + spin_unlock(&sp->so_server->nfs_client->cl_lock); +} +#else /* !CONFIG_NFS_V4_2 */ +static inline void nfs42_complete_copies(struct nfs4_state_owner *sp, + struct nfs4_state *state) +{ +} +#endif /* CONFIG_NFS_V4_2 */ + +static int __nfs4_reclaim_open_state(struct nfs4_state_owner *sp, struct nfs4_state *state, + const struct nfs4_state_recovery_ops *ops) +{ + struct nfs4_lock_state *lock; + int status; + + status = ops->recover_open(sp, state); + if (status < 0) + return status; + + status = nfs4_reclaim_locks(state, ops); + if (status < 0) + return status; + + if (!test_bit(NFS_DELEGATED_STATE, &state->flags)) { + spin_lock(&state->state_lock); + list_for_each_entry(lock, &state->lock_states, ls_locks) { + trace_nfs4_state_lock_reclaim(state, lock); + if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags)) + pr_warn_ratelimited("NFS: %s: Lock reclaim failed!\n", __func__); + } + spin_unlock(&state->state_lock); + } + + nfs42_complete_copies(sp, state); + clear_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags); + return status; +} + +static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs4_state_recovery_ops *ops) +{ + struct nfs4_state *state; + unsigned int loop = 0; + int status = 0; +#ifdef CONFIG_NFS_V4_2 + bool found_ssc_copy_state = false; +#endif /* CONFIG_NFS_V4_2 */ + + /* 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. + */ + spin_lock(&sp->so_lock); + raw_write_seqcount_begin(&sp->so_reclaim_seqcount); +restart: + list_for_each_entry(state, &sp->so_states, open_states) { + if (!test_and_clear_bit(ops->state_flag_bit, &state->flags)) + continue; + if (!nfs4_valid_open_stateid(state)) + continue; + if (state->state == 0) + continue; +#ifdef CONFIG_NFS_V4_2 + if (test_bit(NFS_SRV_SSC_COPY_STATE, &state->flags)) { + nfs4_state_mark_recovery_failed(state, -EIO); + found_ssc_copy_state = true; + continue; + } +#endif /* CONFIG_NFS_V4_2 */ + refcount_inc(&state->count); + spin_unlock(&sp->so_lock); + status = __nfs4_reclaim_open_state(sp, state, ops); + + switch (status) { + default: + if (status >= 0) { + loop = 0; + break; + } + printk(KERN_ERR "NFS: %s: unhandled error %d\n", __func__, status); + fallthrough; + case -ENOENT: + case -ENOMEM: + case -EACCES: + case -EROFS: + case -EIO: + case -ESTALE: + /* Open state on this file cannot be recovered */ + nfs4_state_mark_recovery_failed(state, status); + break; + case -EAGAIN: + ssleep(1); + if (loop++ < 10) { + set_bit(ops->state_flag_bit, &state->flags); + break; + } + fallthrough; + case -NFS4ERR_ADMIN_REVOKED: + case -NFS4ERR_STALE_STATEID: + case -NFS4ERR_OLD_STATEID: + case -NFS4ERR_BAD_STATEID: + case -NFS4ERR_RECLAIM_BAD: + case -NFS4ERR_RECLAIM_CONFLICT: + nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state); + break; + case -NFS4ERR_EXPIRED: + case -NFS4ERR_NO_GRACE: + nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state); + fallthrough; + case -NFS4ERR_STALE_CLIENTID: + case -NFS4ERR_BADSESSION: + case -NFS4ERR_BADSLOT: + case -NFS4ERR_BAD_HIGH_SLOT: + case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION: + case -ETIMEDOUT: + goto out_err; + } + nfs4_put_open_state(state); + spin_lock(&sp->so_lock); + goto restart; + } + raw_write_seqcount_end(&sp->so_reclaim_seqcount); + spin_unlock(&sp->so_lock); +#ifdef CONFIG_NFS_V4_2 + if (found_ssc_copy_state) + return -EIO; +#endif /* CONFIG_NFS_V4_2 */ + return 0; +out_err: + nfs4_put_open_state(state); + spin_lock(&sp->so_lock); + raw_write_seqcount_end(&sp->so_reclaim_seqcount); + spin_unlock(&sp->so_lock); + return status; +} + +static void nfs4_clear_open_state(struct nfs4_state *state) +{ + struct nfs4_lock_state *lock; + + clear_bit(NFS_DELEGATED_STATE, &state->flags); + clear_bit(NFS_O_RDONLY_STATE, &state->flags); + clear_bit(NFS_O_WRONLY_STATE, &state->flags); + clear_bit(NFS_O_RDWR_STATE, &state->flags); + spin_lock(&state->state_lock); + list_for_each_entry(lock, &state->lock_states, ls_locks) { + lock->ls_seqid.flags = 0; + clear_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags); + } + spin_unlock(&state->state_lock); +} + +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; + + 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) { + if (mark_reclaim(clp, state)) + nfs4_clear_open_state(state); + } + 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) +{ + set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state); + /* Mark all delegations for reclaim */ + nfs_delegation_mark_reclaim(clp); + nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot); +} + +static int nfs4_reclaim_complete(struct nfs_client *clp, + const struct nfs4_state_recovery_ops *ops, + const struct cred *cred) +{ + /* Notify the server we're done reclaiming our state */ + if (ops->reclaim_complete) + return ops->reclaim_complete(clp, cred); + return 0; +} + +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; + + 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)) + 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; +} + +static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp) +{ + const struct nfs4_state_recovery_ops *ops; + const struct cred *cred; + int err; + + if (!nfs4_state_clear_reclaim_reboot(clp)) + return; + ops = clp->cl_mvops->reboot_recovery_ops; + cred = nfs4_get_clid_cred(clp); + err = nfs4_reclaim_complete(clp, ops, cred); + put_cred(cred); + if (err == -NFS4ERR_CONN_NOT_BOUND_TO_SESSION) + set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state); +} + +static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp) +{ + nfs_mark_test_expired_all_delegations(clp); + nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce); +} + +static int nfs4_recovery_handle_error(struct nfs_client *clp, int error) +{ + switch (error) { + case 0: + break; + case -NFS4ERR_CB_PATH_DOWN: + nfs40_handle_cb_pathdown(clp); + break; + case -NFS4ERR_NO_GRACE: + nfs4_state_end_reclaim_reboot(clp); + break; + case -NFS4ERR_STALE_CLIENTID: + set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state); + nfs4_state_start_reclaim_reboot(clp); + break; + case -NFS4ERR_EXPIRED: + set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state); + nfs4_state_start_reclaim_nograce(clp); + break; + case -NFS4ERR_BADSESSION: + case -NFS4ERR_BADSLOT: + case -NFS4ERR_BAD_HIGH_SLOT: + case -NFS4ERR_DEADSESSION: + case -NFS4ERR_SEQ_FALSE_RETRY: + case -NFS4ERR_SEQ_MISORDERED: + set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state); + /* Zero session reset errors */ + break; + case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION: + set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state); + break; + default: + dprintk("%s: failed to handle error %d for server %s\n", + __func__, error, clp->cl_hostname); + return error; + } + dprintk("%s: handled error %d for server %s\n", __func__, error, + clp->cl_hostname); + return 0; +} + +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; + LIST_HEAD(freeme); + int status = 0; + +restart: + rcu_read_lock(); + list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { + nfs4_purge_state_owners(server, &freeme); + 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; + if (!atomic_inc_not_zero(&sp->so_count)) + continue; + 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); + status = nfs4_recovery_handle_error(clp, status); + return (status != 0) ? status : -EAGAIN; + } + + nfs4_put_state_owner(sp); + goto restart; + } + spin_unlock(&clp->cl_lock); + } + rcu_read_unlock(); + nfs4_free_state_owners(&freeme); + return 0; +} + +static int nfs4_check_lease(struct nfs_client *clp) +{ + const struct cred *cred; + const struct nfs4_state_maintenance_ops *ops = + clp->cl_mvops->state_renewal_ops; + int status; + + /* Is the client already known to have an expired lease? */ + if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) + return 0; + cred = ops->get_state_renewal_cred(clp); + if (cred == NULL) { + cred = nfs4_get_clid_cred(clp); + status = -ENOKEY; + if (cred == NULL) + goto out; + } + status = ops->renew_lease(clp, cred); + put_cred(cred); + if (status == -ETIMEDOUT) { + set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state); + return 0; + } +out: + return nfs4_recovery_handle_error(clp, status); +} + +/* Set NFS4CLNT_LEASE_EXPIRED and reclaim reboot state for all v4.0 errors + * and for recoverable errors on EXCHANGE_ID for v4.1 + */ +static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status) +{ + switch (status) { + case -NFS4ERR_SEQ_MISORDERED: + if (test_and_set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) + return -ESERVERFAULT; + /* Lease confirmation error: retry after purging the lease */ + ssleep(1); + clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); + break; + case -NFS4ERR_STALE_CLIENTID: + clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); + nfs4_state_start_reclaim_reboot(clp); + break; + case -NFS4ERR_CLID_INUSE: + pr_err("NFS: Server %s reports our clientid is in use\n", + clp->cl_hostname); + nfs_mark_client_ready(clp, -EPERM); + clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); + return -EPERM; + case -EACCES: + case -NFS4ERR_DELAY: + case -EAGAIN: + ssleep(1); + break; + + case -NFS4ERR_MINOR_VERS_MISMATCH: + if (clp->cl_cons_state == NFS_CS_SESSION_INITING) + nfs_mark_client_ready(clp, -EPROTONOSUPPORT); + dprintk("%s: exit with error %d for server %s\n", + __func__, -EPROTONOSUPPORT, clp->cl_hostname); + return -EPROTONOSUPPORT; + case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery + * in nfs4_exchange_id */ + default: + dprintk("%s: exit with error %d for server %s\n", __func__, + status, clp->cl_hostname); + return status; + } + set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state); + dprintk("%s: handled error %d for server %s\n", __func__, status, + clp->cl_hostname); + return 0; +} + +static int nfs4_establish_lease(struct nfs_client *clp) +{ + const struct cred *cred; + const struct nfs4_state_recovery_ops *ops = + clp->cl_mvops->reboot_recovery_ops; + int status; + + status = nfs4_begin_drain_session(clp); + if (status != 0) + return status; + cred = nfs4_get_clid_cred(clp); + if (cred == NULL) + return -ENOENT; + status = ops->establish_clid(clp, cred); + put_cred(cred); + if (status != 0) + return status; + pnfs_destroy_all_layouts(clp); + return 0; +} + +/* + * Returns zero or a negative errno. NFS4ERR values are converted + * to local errno values. + */ +static int nfs4_reclaim_lease(struct nfs_client *clp) +{ + int status; + + status = nfs4_establish_lease(clp); + if (status < 0) + return nfs4_handle_reclaim_lease_error(clp, status); + if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH, &clp->cl_state)) + nfs4_state_start_reclaim_nograce(clp); + if (!test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) + set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state); + clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state); + clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state); + return 0; +} + +static int nfs4_purge_lease(struct nfs_client *clp) +{ + int status; + + status = nfs4_establish_lease(clp); + if (status < 0) + return nfs4_handle_reclaim_lease_error(clp, status); + clear_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state); + set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state); + nfs4_state_start_reclaim_nograce(clp); + return 0; +} + +/* + * Try remote migration of one FSID from a source server to a + * destination server. The source server provides a list of + * potential destinations. + * + * Returns zero or a negative NFS4ERR status code. + */ +static int nfs4_try_migration(struct nfs_server *server, const struct cred *cred) +{ + struct nfs_client *clp = server->nfs_client; + struct nfs4_fs_locations *locations = NULL; + struct inode *inode; + struct page *page; + int status, result; + + dprintk("--> %s: FSID %llx:%llx on \"%s\"\n", __func__, + (unsigned long long)server->fsid.major, + (unsigned long long)server->fsid.minor, + clp->cl_hostname); + + result = 0; + page = alloc_page(GFP_KERNEL); + locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL); + if (page == NULL || locations == NULL) { + dprintk("<-- %s: no memory\n", __func__); + goto out; + } + + inode = d_inode(server->super->s_root); + result = nfs4_proc_get_locations(inode, locations, page, cred); + if (result) { + dprintk("<-- %s: failed to retrieve fs_locations: %d\n", + __func__, result); + goto out; + } + + result = -NFS4ERR_NXIO; + if (!locations->nlocations) + goto out; + + if (!(locations->fattr.valid & NFS_ATTR_FATTR_V4_LOCATIONS)) { + dprintk("<-- %s: No fs_locations data, migration skipped\n", + __func__); + goto out; + } + + status = nfs4_begin_drain_session(clp); + if (status != 0) { + result = status; + goto out; + } + + status = nfs4_replace_transport(server, locations); + if (status != 0) { + dprintk("<-- %s: failed to replace transport: %d\n", + __func__, status); + goto out; + } + + result = 0; + dprintk("<-- %s: migration succeeded\n", __func__); + +out: + if (page != NULL) + __free_page(page); + kfree(locations); + if (result) { + pr_err("NFS: migration recovery failed (server %s)\n", + clp->cl_hostname); + set_bit(NFS_MIG_FAILED, &server->mig_status); + } + return result; +} + +/* + * Returns zero or a negative NFS4ERR status code. + */ +static int nfs4_handle_migration(struct nfs_client *clp) +{ + const struct nfs4_state_maintenance_ops *ops = + clp->cl_mvops->state_renewal_ops; + struct nfs_server *server; + const struct cred *cred; + + dprintk("%s: migration reported on \"%s\"\n", __func__, + clp->cl_hostname); + + cred = ops->get_state_renewal_cred(clp); + if (cred == NULL) + return -NFS4ERR_NOENT; + + clp->cl_mig_gen++; +restart: + rcu_read_lock(); + list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { + int status; + + if (server->mig_gen == clp->cl_mig_gen) + continue; + server->mig_gen = clp->cl_mig_gen; + + if (!test_and_clear_bit(NFS_MIG_IN_TRANSITION, + &server->mig_status)) + continue; + + rcu_read_unlock(); + status = nfs4_try_migration(server, cred); + if (status < 0) { + put_cred(cred); + return status; + } + goto restart; + } + rcu_read_unlock(); + put_cred(cred); + return 0; +} + +/* + * Test each nfs_server on the clp's cl_superblocks list to see + * if it's moved to another server. Stop when the server no longer + * returns NFS4ERR_LEASE_MOVED. + */ +static int nfs4_handle_lease_moved(struct nfs_client *clp) +{ + const struct nfs4_state_maintenance_ops *ops = + clp->cl_mvops->state_renewal_ops; + struct nfs_server *server; + const struct cred *cred; + + dprintk("%s: lease moved reported on \"%s\"\n", __func__, + clp->cl_hostname); + + cred = ops->get_state_renewal_cred(clp); + if (cred == NULL) + return -NFS4ERR_NOENT; + + clp->cl_mig_gen++; +restart: + rcu_read_lock(); + list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { + struct inode *inode; + int status; + + if (server->mig_gen == clp->cl_mig_gen) + continue; + server->mig_gen = clp->cl_mig_gen; + + rcu_read_unlock(); + + inode = d_inode(server->super->s_root); + status = nfs4_proc_fsid_present(inode, cred); + if (status != -NFS4ERR_MOVED) + goto restart; /* wasn't this one */ + if (nfs4_try_migration(server, cred) == -NFS4ERR_LEASE_MOVED) + goto restart; /* there are more */ + goto out; + } + rcu_read_unlock(); + +out: + put_cred(cred); + return 0; +} + +/** + * nfs4_discover_server_trunking - Detect server IP address trunking + * + * @clp: nfs_client under test + * @result: OUT: found nfs_client, or clp + * + * Returns zero or a negative errno. If zero is returned, + * an nfs_client pointer is planted in "result". + * + * Note: since we are invoked in process context, and + * not from inside the state manager, we cannot use + * nfs4_handle_reclaim_lease_error(). + */ +int nfs4_discover_server_trunking(struct nfs_client *clp, + struct nfs_client **result) +{ + const struct nfs4_state_recovery_ops *ops = + clp->cl_mvops->reboot_recovery_ops; + struct rpc_clnt *clnt; + const struct cred *cred; + int i, status; + + dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname); + + clnt = clp->cl_rpcclient; + i = 0; + + mutex_lock(&nfs_clid_init_mutex); +again: + status = -ENOENT; + cred = nfs4_get_clid_cred(clp); + if (cred == NULL) + goto out_unlock; + + status = ops->detect_trunking(clp, result, cred); + put_cred(cred); + switch (status) { + case 0: + case -EINTR: + case -ERESTARTSYS: + break; + case -ETIMEDOUT: + if (clnt->cl_softrtry) + break; + fallthrough; + case -NFS4ERR_DELAY: + case -EAGAIN: + ssleep(1); + fallthrough; + case -NFS4ERR_STALE_CLIENTID: + dprintk("NFS: %s after status %d, retrying\n", + __func__, status); + goto again; + case -EACCES: + if (i++ == 0) { + nfs4_root_machine_cred(clp); + goto again; + } + if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX) + break; + fallthrough; + case -NFS4ERR_CLID_INUSE: + case -NFS4ERR_WRONGSEC: + /* No point in retrying if we already used RPC_AUTH_UNIX */ + if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX) { + status = -EPERM; + break; + } + clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_UNIX); + if (IS_ERR(clnt)) { + status = PTR_ERR(clnt); + break; + } + /* Note: this is safe because we haven't yet marked the + * client as ready, so we are the only user of + * clp->cl_rpcclient + */ + clnt = xchg(&clp->cl_rpcclient, clnt); + rpc_shutdown_client(clnt); + clnt = clp->cl_rpcclient; + goto again; + + case -NFS4ERR_MINOR_VERS_MISMATCH: + status = -EPROTONOSUPPORT; + break; + + case -EKEYEXPIRED: + case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery + * in nfs4_exchange_id */ + status = -EKEYEXPIRED; + break; + default: + pr_warn("NFS: %s unhandled error %d. Exiting with error EIO\n", + __func__, status); + status = -EIO; + } + +out_unlock: + mutex_unlock(&nfs_clid_init_mutex); + dprintk("NFS: %s: status = %d\n", __func__, status); + return status; +} + +#ifdef CONFIG_NFS_V4_1 +void nfs4_schedule_session_recovery(struct nfs4_session *session, int err) +{ + struct nfs_client *clp = session->clp; + + switch (err) { + default: + set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state); + break; + case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION: + set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state); + } + nfs4_schedule_state_manager(clp); +} +EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery); + +void nfs41_notify_server(struct nfs_client *clp) +{ + /* Use CHECK_LEASE to ping the server with a SEQUENCE */ + set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state); + nfs4_schedule_state_manager(clp); +} + +static void nfs4_reset_all_state(struct nfs_client *clp) +{ + if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) { + set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state); + clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); + nfs4_state_start_reclaim_nograce(clp); + dprintk("%s: scheduling reset of all state for server %s!\n", + __func__, clp->cl_hostname); + nfs4_schedule_state_manager(clp); + } +} + +static void nfs41_handle_server_reboot(struct nfs_client *clp) +{ + if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) { + nfs4_state_start_reclaim_reboot(clp); + dprintk("%s: server %s rebooted!\n", __func__, + clp->cl_hostname); + nfs4_schedule_state_manager(clp); + } +} + +static void nfs41_handle_all_state_revoked(struct nfs_client *clp) +{ + nfs4_reset_all_state(clp); + dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname); +} + +static void nfs41_handle_some_state_revoked(struct nfs_client *clp) +{ + nfs4_state_start_reclaim_nograce(clp); + nfs4_schedule_state_manager(clp); + + dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname); +} + +static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp) +{ + /* FIXME: For now, we destroy all layouts. */ + pnfs_destroy_all_layouts(clp); + nfs_test_expired_all_delegations(clp); + dprintk("%s: Recallable state revoked on server %s!\n", __func__, + clp->cl_hostname); +} + +static void nfs41_handle_backchannel_fault(struct nfs_client *clp) +{ + set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state); + nfs4_schedule_state_manager(clp); + + dprintk("%s: server %s declared a backchannel fault\n", __func__, + clp->cl_hostname); +} + +static void nfs41_handle_cb_path_down(struct nfs_client *clp) +{ + if (test_and_set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, + &clp->cl_state) == 0) + nfs4_schedule_state_manager(clp); +} + +void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags, + bool recovery) +{ + if (!flags) + return; + + dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n", + __func__, clp->cl_hostname, clp->cl_clientid, flags); + /* + * If we're called from the state manager thread, then assume we're + * already handling the RECLAIM_NEEDED and/or STATE_REVOKED. + * Those flags are expected to remain set until we're done + * recovering (see RFC5661, section 18.46.3). + */ + if (recovery) + goto out_recovery; + + if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED) + nfs41_handle_server_reboot(clp); + if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED)) + nfs41_handle_all_state_revoked(clp); + if (flags & (SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED | + SEQ4_STATUS_ADMIN_STATE_REVOKED)) + nfs41_handle_some_state_revoked(clp); + if (flags & SEQ4_STATUS_LEASE_MOVED) + nfs4_schedule_lease_moved_recovery(clp); + if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED) + nfs41_handle_recallable_state_revoked(clp); +out_recovery: + if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT) + nfs41_handle_backchannel_fault(clp); + else if (flags & (SEQ4_STATUS_CB_PATH_DOWN | + SEQ4_STATUS_CB_PATH_DOWN_SESSION)) + nfs41_handle_cb_path_down(clp); +} + +static int nfs4_reset_session(struct nfs_client *clp) +{ + const struct cred *cred; + int status; + + if (!nfs4_has_session(clp)) + return 0; + status = nfs4_begin_drain_session(clp); + if (status != 0) + return status; + cred = nfs4_get_clid_cred(clp); + status = nfs4_proc_destroy_session(clp->cl_session, cred); + switch (status) { + case 0: + case -NFS4ERR_BADSESSION: + case -NFS4ERR_DEADSESSION: + break; + case -NFS4ERR_BACK_CHAN_BUSY: + case -NFS4ERR_DELAY: + set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state); + status = 0; + ssleep(1); + goto out; + default: + status = nfs4_recovery_handle_error(clp, status); + goto out; + } + + memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN); + status = nfs4_proc_create_session(clp, cred); + if (status) { + dprintk("%s: session reset failed with status %d for server %s!\n", + __func__, status, clp->cl_hostname); + status = nfs4_handle_reclaim_lease_error(clp, status); + goto out; + } + nfs41_finish_session_reset(clp); + dprintk("%s: session reset was successful for server %s!\n", + __func__, clp->cl_hostname); +out: + put_cred(cred); + return status; +} + +static int nfs4_bind_conn_to_session(struct nfs_client *clp) +{ + const struct cred *cred; + int ret; + + if (!nfs4_has_session(clp)) + return 0; + ret = nfs4_begin_drain_session(clp); + if (ret != 0) + return ret; + cred = nfs4_get_clid_cred(clp); + ret = nfs4_proc_bind_conn_to_session(clp, cred); + put_cred(cred); + clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state); + switch (ret) { + case 0: + dprintk("%s: bind_conn_to_session was successful for server %s!\n", + __func__, clp->cl_hostname); + break; + case -NFS4ERR_DELAY: + ssleep(1); + set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state); + break; + default: + return nfs4_recovery_handle_error(clp, ret); + } + return 0; +} + +static void nfs4_layoutreturn_any_run(struct nfs_client *clp) +{ + int iomode = 0; + + if (test_and_clear_bit(NFS4CLNT_RECALL_ANY_LAYOUT_READ, &clp->cl_state)) + iomode += IOMODE_READ; + if (test_and_clear_bit(NFS4CLNT_RECALL_ANY_LAYOUT_RW, &clp->cl_state)) + iomode += IOMODE_RW; + /* Note: IOMODE_READ + IOMODE_RW == IOMODE_ANY */ + if (iomode) { + pnfs_layout_return_unused_byclid(clp, iomode); + set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state); + } +} +#else /* CONFIG_NFS_V4_1 */ +static int nfs4_reset_session(struct nfs_client *clp) { return 0; } + +static int nfs4_bind_conn_to_session(struct nfs_client *clp) +{ + return 0; +} + +static void nfs4_layoutreturn_any_run(struct nfs_client *clp) +{ +} +#endif /* CONFIG_NFS_V4_1 */ + +static void nfs4_state_manager(struct nfs_client *clp) +{ + unsigned int memflags; + int status = 0; + const char *section = "", *section_sep = ""; + + /* + * State recovery can deadlock if the direct reclaim code tries + * start NFS writeback. So ensure memory allocations are all + * GFP_NOFS. + */ + memflags = memalloc_nofs_save(); + + /* Ensure exclusive access to NFSv4 state */ + do { + trace_nfs4_state_mgr(clp); + clear_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state); + if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) { + section = "purge state"; + status = nfs4_purge_lease(clp); + if (status < 0) + goto out_error; + continue; + } + + if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) { + section = "lease expired"; + /* We're going to have to re-establish a clientid */ + status = nfs4_reclaim_lease(clp); + if (status < 0) + goto out_error; + continue; + } + + /* Initialize or reset the session */ + if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) { + section = "reset session"; + status = nfs4_reset_session(clp); + if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) + continue; + if (status < 0) + goto out_error; + } + + /* Send BIND_CONN_TO_SESSION */ + if (test_and_clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, + &clp->cl_state)) { + section = "bind conn to session"; + status = nfs4_bind_conn_to_session(clp); + if (status < 0) + goto out_error; + continue; + } + + if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) { + section = "check lease"; + status = nfs4_check_lease(clp); + if (status < 0) + goto out_error; + continue; + } + + if (test_and_clear_bit(NFS4CLNT_MOVED, &clp->cl_state)) { + section = "migration"; + status = nfs4_handle_migration(clp); + if (status < 0) + goto out_error; + } + + if (test_and_clear_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state)) { + section = "lease moved"; + status = nfs4_handle_lease_moved(clp); + if (status < 0) + goto out_error; + } + + /* First recover reboot state... */ + if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) { + section = "reclaim reboot"; + status = nfs4_do_reclaim(clp, + clp->cl_mvops->reboot_recovery_ops); + if (status == -EAGAIN) + continue; + if (status < 0) + goto out_error; + nfs4_state_end_reclaim_reboot(clp); + continue; + } + + /* Detect expired delegations... */ + if (test_and_clear_bit(NFS4CLNT_DELEGATION_EXPIRED, &clp->cl_state)) { + section = "detect expired delegations"; + nfs_reap_expired_delegations(clp); + continue; + } + + /* Now recover expired state... */ + if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) { + section = "reclaim nograce"; + status = nfs4_do_reclaim(clp, + clp->cl_mvops->nograce_recovery_ops); + if (status == -EAGAIN) + continue; + if (status < 0) + goto out_error; + clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state); + } + + memalloc_nofs_restore(memflags); + nfs4_end_drain_session(clp); + nfs4_clear_state_manager_bit(clp); + + if (test_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state) && + !test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, + &clp->cl_state)) { + memflags = memalloc_nofs_save(); + continue; + } + + if (!test_and_set_bit(NFS4CLNT_RECALL_RUNNING, &clp->cl_state)) { + if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) { + nfs_client_return_marked_delegations(clp); + set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state); + } + nfs4_layoutreturn_any_run(clp); + clear_bit(NFS4CLNT_RECALL_RUNNING, &clp->cl_state); + } + + return; + + } while (refcount_read(&clp->cl_count) > 1 && !signalled()); + goto out_drain; + +out_error: + if (strlen(section)) + section_sep = ": "; + trace_nfs4_state_mgr_failed(clp, section, status); + pr_warn_ratelimited("NFS: state manager%s%s failed on NFSv4 server %s" + " with error %d\n", section_sep, section, + clp->cl_hostname, -status); + ssleep(1); +out_drain: + memalloc_nofs_restore(memflags); + nfs4_end_drain_session(clp); + nfs4_clear_state_manager_bit(clp); +} + +static int nfs4_run_state_manager(void *ptr) +{ + struct nfs_client *clp = ptr; + struct rpc_clnt *cl = clp->cl_rpcclient; + + while (cl != cl->cl_parent) + cl = cl->cl_parent; + + allow_signal(SIGKILL); +again: + nfs4_state_manager(clp); + + if (test_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state) && + !test_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state)) { + wait_var_event_interruptible(&clp->cl_state, + test_bit(NFS4CLNT_RUN_MANAGER, + &clp->cl_state)); + if (!atomic_read(&cl->cl_swapper)) + clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state); + if (refcount_read(&clp->cl_count) > 1 && !signalled() && + !test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state)) + goto again; + /* Either no longer a swapper, or were signalled */ + clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state); + } + + if (refcount_read(&clp->cl_count) > 1 && !signalled() && + test_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state) && + !test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state)) + goto again; + + nfs_put_client(clp); + module_put_and_exit(0); + return 0; +} + +/* + * Local variables: + * c-basic-offset: 8 + * End: + */ |