1 files changed, 721 insertions, 0 deletions

diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c
new file mode 100644
index 000000000000..3c1bfa155571
--- /dev/null
+++ b/fs/nfsd/nfs4layouts.c
@@ -0,0 +1,721 @@
+/*
+ * Copyright (c) 2014 Christoph Hellwig.
+ */
+#include <linux/kmod.h>
+#include <linux/file.h>
+#include <linux/jhash.h>
+#include <linux/sched.h>
+#include <linux/sunrpc/addr.h>
+
+#include "pnfs.h"
+#include "netns.h"
+#include "trace.h"
+
+#define NFSDDBG_FACILITY                NFSDDBG_PNFS
+
+struct nfs4_layout {
+        struct list_head                lo_perstate;
+        struct nfs4_layout_stateid      *lo_state;
+        struct nfsd4_layout_seg         lo_seg;
+};
+
+static struct kmem_cache *nfs4_layout_cache;
+static struct kmem_cache *nfs4_layout_stateid_cache;
+
+static struct nfsd4_callback_ops nfsd4_cb_layout_ops;
+static const struct lock_manager_operations nfsd4_layouts_lm_ops;
+
+const struct nfsd4_layout_ops *nfsd4_layout_ops[LAYOUT_TYPE_MAX] =  {
+        [LAYOUT_BLOCK_VOLUME]   = &bl_layout_ops,
+};
+
+/* pNFS device ID to export fsid mapping */
+#define DEVID_HASH_BITS 8
+#define DEVID_HASH_SIZE (1 << DEVID_HASH_BITS)
+#define DEVID_HASH_MASK (DEVID_HASH_SIZE - 1)
+static u64 nfsd_devid_seq = 1;
+static struct list_head nfsd_devid_hash[DEVID_HASH_SIZE];
+static DEFINE_SPINLOCK(nfsd_devid_lock);
+
+static inline u32 devid_hashfn(u64 idx)
+{
+        return jhash_2words(idx, idx >> 32, 0) & DEVID_HASH_MASK;
+}
+
+static void
+nfsd4_alloc_devid_map(const struct svc_fh *fhp)
+{
+        const struct knfsd_fh *fh = &fhp->fh_handle;
+        size_t fsid_len = key_len(fh->fh_fsid_type);
+        struct nfsd4_deviceid_map *map, *old;
+        int i;
+
+        map = kzalloc(sizeof(*map) + fsid_len, GFP_KERNEL);
+        if (!map)
+                return;
+
+        map->fsid_type = fh->fh_fsid_type;
+        memcpy(&map->fsid, fh->fh_fsid, fsid_len);
+
+        spin_lock(&nfsd_devid_lock);
+        if (fhp->fh_export->ex_devid_map)
+                goto out_unlock;
+
+        for (i = 0; i < DEVID_HASH_SIZE; i++) {
+                list_for_each_entry(old, &nfsd_devid_hash[i], hash) {
+                        if (old->fsid_type != fh->fh_fsid_type)
+                                continue;
+                        if (memcmp(old->fsid, fh->fh_fsid,
+                                        key_len(old->fsid_type)))
+                                continue;
+
+                        fhp->fh_export->ex_devid_map = old;
+                        goto out_unlock;
+                }
+        }
+
+        map->idx = nfsd_devid_seq++;
+        list_add_tail_rcu(&map->hash, &nfsd_devid_hash[devid_hashfn(map->idx)]);
+        fhp->fh_export->ex_devid_map = map;
+        map = NULL;
+
+out_unlock:
+        spin_unlock(&nfsd_devid_lock);
+        kfree(map);
+}
+
+struct nfsd4_deviceid_map *
+nfsd4_find_devid_map(int idx)
+{
+        struct nfsd4_deviceid_map *map, *ret = NULL;
+
+        rcu_read_lock();
+        list_for_each_entry_rcu(map, &nfsd_devid_hash[devid_hashfn(idx)], hash)
+                if (map->idx == idx)
+                        ret = map;
+        rcu_read_unlock();
+
+        return ret;
+}
+
+int
+nfsd4_set_deviceid(struct nfsd4_deviceid *id, const struct svc_fh *fhp,
+                u32 device_generation)
+{
+        if (!fhp->fh_export->ex_devid_map) {
+                nfsd4_alloc_devid_map(fhp);
+                if (!fhp->fh_export->ex_devid_map)
+                        return -ENOMEM;
+        }
+
+        id->fsid_idx = fhp->fh_export->ex_devid_map->idx;
+        id->generation = device_generation;
+        id->pad = 0;
+        return 0;
+}
+
+void nfsd4_setup_layout_type(struct svc_export *exp)
+{
+        struct super_block *sb = exp->ex_path.mnt->mnt_sb;
+
+        if (exp->ex_flags & NFSEXP_NOPNFS)
+                return;
+
+        if (sb->s_export_op->get_uuid &&
+            sb->s_export_op->map_blocks &&
+            sb->s_export_op->commit_blocks)
+                exp->ex_layout_type = LAYOUT_BLOCK_VOLUME;
+}
+
+static void
+nfsd4_free_layout_stateid(struct nfs4_stid *stid)
+{
+        struct nfs4_layout_stateid *ls = layoutstateid(stid);
+        struct nfs4_client *clp = ls->ls_stid.sc_client;
+        struct nfs4_file *fp = ls->ls_stid.sc_file;
+
+        trace_layoutstate_free(&ls->ls_stid.sc_stateid);
+
+        spin_lock(&clp->cl_lock);
+        list_del_init(&ls->ls_perclnt);
+        spin_unlock(&clp->cl_lock);
+
+        spin_lock(&fp->fi_lock);
+        list_del_init(&ls->ls_perfile);
+        spin_unlock(&fp->fi_lock);
+
+        vfs_setlease(ls->ls_file, F_UNLCK, NULL, (void **)&ls);
+        fput(ls->ls_file);
+
+        if (ls->ls_recalled)
+                atomic_dec(&ls->ls_stid.sc_file->fi_lo_recalls);
+
+        kmem_cache_free(nfs4_layout_stateid_cache, ls);
+}
+
+static int
+nfsd4_layout_setlease(struct nfs4_layout_stateid *ls)
+{
+        struct file_lock *fl;
+        int status;
+
+        fl = locks_alloc_lock();
+        if (!fl)
+                return -ENOMEM;
+        locks_init_lock(fl);
+        fl->fl_lmops = &nfsd4_layouts_lm_ops;
+        fl->fl_flags = FL_LAYOUT;
+        fl->fl_type = F_RDLCK;
+        fl->fl_end = OFFSET_MAX;
+        fl->fl_owner = ls;
+        fl->fl_pid = current->tgid;
+        fl->fl_file = ls->ls_file;
+
+        status = vfs_setlease(fl->fl_file, fl->fl_type, &fl, NULL);
+        if (status) {
+                locks_free_lock(fl);
+                return status;
+        }
+        BUG_ON(fl != NULL);
+        return 0;
+}
+
+static struct nfs4_layout_stateid *
+nfsd4_alloc_layout_stateid(struct nfsd4_compound_state *cstate,
+                struct nfs4_stid *parent, u32 layout_type)
+{
+        struct nfs4_client *clp = cstate->clp;
+        struct nfs4_file *fp = parent->sc_file;
+        struct nfs4_layout_stateid *ls;
+        struct nfs4_stid *stp;
+
+        stp = nfs4_alloc_stid(cstate->clp, nfs4_layout_stateid_cache);
+        if (!stp)
+                return NULL;
+        stp->sc_free = nfsd4_free_layout_stateid;
+        get_nfs4_file(fp);
+        stp->sc_file = fp;
+
+        ls = layoutstateid(stp);
+        INIT_LIST_HEAD(&ls->ls_perclnt);
+        INIT_LIST_HEAD(&ls->ls_perfile);
+        spin_lock_init(&ls->ls_lock);
+        INIT_LIST_HEAD(&ls->ls_layouts);
+        ls->ls_layout_type = layout_type;
+        nfsd4_init_cb(&ls->ls_recall, clp, &nfsd4_cb_layout_ops,
+                        NFSPROC4_CLNT_CB_LAYOUT);
+
+        if (parent->sc_type == NFS4_DELEG_STID)
+                ls->ls_file = get_file(fp->fi_deleg_file);
+        else
+                ls->ls_file = find_any_file(fp);
+        BUG_ON(!ls->ls_file);
+
+        if (nfsd4_layout_setlease(ls)) {
+                put_nfs4_file(fp);
+                kmem_cache_free(nfs4_layout_stateid_cache, ls);
+                return NULL;
+        }
+
+        spin_lock(&clp->cl_lock);
+        stp->sc_type = NFS4_LAYOUT_STID;
+        list_add(&ls->ls_perclnt, &clp->cl_lo_states);
+        spin_unlock(&clp->cl_lock);
+
+        spin_lock(&fp->fi_lock);
+        list_add(&ls->ls_perfile, &fp->fi_lo_states);
+        spin_unlock(&fp->fi_lock);
+
+        trace_layoutstate_alloc(&ls->ls_stid.sc_stateid);
+        return ls;
+}
+
+__be32
+nfsd4_preprocess_layout_stateid(struct svc_rqst *rqstp,
+                struct nfsd4_compound_state *cstate, stateid_t *stateid,
+                bool create, u32 layout_type, struct nfs4_layout_stateid **lsp)
+{
+        struct nfs4_layout_stateid *ls;
+        struct nfs4_stid *stid;
+        unsigned char typemask = NFS4_LAYOUT_STID;
+        __be32 status;
+
+        if (create)
+                typemask |= (NFS4_OPEN_STID | NFS4_LOCK_STID | NFS4_DELEG_STID);
+
+        status = nfsd4_lookup_stateid(cstate, stateid, typemask, &stid,
+                        net_generic(SVC_NET(rqstp), nfsd_net_id));
+        if (status)
+                goto out;
+
+        if (!fh_match(&cstate->current_fh.fh_handle,
+                      &stid->sc_file->fi_fhandle)) {
+                status = nfserr_bad_stateid;
+                goto out_put_stid;
+        }
+
+        if (stid->sc_type != NFS4_LAYOUT_STID) {
+                ls = nfsd4_alloc_layout_stateid(cstate, stid, layout_type);
+                nfs4_put_stid(stid);
+
+                status = nfserr_jukebox;
+                if (!ls)
+                        goto out;
+        } else {
+                ls = container_of(stid, struct nfs4_layout_stateid, ls_stid);
+
+                status = nfserr_bad_stateid;
+                if (stateid->si_generation > stid->sc_stateid.si_generation)
+                        goto out_put_stid;
+                if (layout_type != ls->ls_layout_type)
+                        goto out_put_stid;
+        }
+
+        *lsp = ls;
+        return 0;
+
+out_put_stid:
+        nfs4_put_stid(stid);
+out:
+        return status;
+}
+
+static void
+nfsd4_recall_file_layout(struct nfs4_layout_stateid *ls)
+{
+        spin_lock(&ls->ls_lock);
+        if (ls->ls_recalled)
+                goto out_unlock;
+
+        ls->ls_recalled = true;
+        atomic_inc(&ls->ls_stid.sc_file->fi_lo_recalls);
+        if (list_empty(&ls->ls_layouts))
+                goto out_unlock;
+
+        trace_layout_recall(&ls->ls_stid.sc_stateid);
+
+        atomic_inc(&ls->ls_stid.sc_count);
+        update_stateid(&ls->ls_stid.sc_stateid);
+        memcpy(&ls->ls_recall_sid, &ls->ls_stid.sc_stateid, sizeof(stateid_t));
+        nfsd4_run_cb(&ls->ls_recall);
+
+out_unlock:
+        spin_unlock(&ls->ls_lock);
+}
+
+static inline u64
+layout_end(struct nfsd4_layout_seg *seg)
+{
+        u64 end = seg->offset + seg->length;
+        return end >= seg->offset ? end : NFS4_MAX_UINT64;
+}
+
+static void
+layout_update_len(struct nfsd4_layout_seg *lo, u64 end)
+{
+        if (end == NFS4_MAX_UINT64)
+                lo->length = NFS4_MAX_UINT64;
+        else
+                lo->length = end - lo->offset;
+}
+
+static bool
+layouts_overlapping(struct nfs4_layout *lo, struct nfsd4_layout_seg *s)
+{
+        if (s->iomode != IOMODE_ANY && s->iomode != lo->lo_seg.iomode)
+                return false;
+        if (layout_end(&lo->lo_seg) <= s->offset)
+                return false;
+        if (layout_end(s) <= lo->lo_seg.offset)
+                return false;
+        return true;
+}
+
+static bool
+layouts_try_merge(struct nfsd4_layout_seg *lo, struct nfsd4_layout_seg *new)
+{
+        if (lo->iomode != new->iomode)
+                return false;
+        if (layout_end(new) < lo->offset)
+                return false;
+        if (layout_end(lo) < new->offset)
+                return false;
+
+        lo->offset = min(lo->offset, new->offset);
+        layout_update_len(lo, max(layout_end(lo), layout_end(new)));
+        return true;
+}
+
+static __be32
+nfsd4_recall_conflict(struct nfs4_layout_stateid *ls)
+{
+        struct nfs4_file *fp = ls->ls_stid.sc_file;
+        struct nfs4_layout_stateid *l, *n;
+        __be32 nfserr = nfs_ok;
+
+        assert_spin_locked(&fp->fi_lock);
+
+        list_for_each_entry_safe(l, n, &fp->fi_lo_states, ls_perfile) {
+                if (l != ls) {
+                        nfsd4_recall_file_layout(l);
+                        nfserr = nfserr_recallconflict;
+                }
+        }
+
+        return nfserr;
+}
+
+__be32
+nfsd4_insert_layout(struct nfsd4_layoutget *lgp, struct nfs4_layout_stateid *ls)
+{
+        struct nfsd4_layout_seg *seg = &lgp->lg_seg;
+        struct nfs4_file *fp = ls->ls_stid.sc_file;
+        struct nfs4_layout *lp, *new = NULL;
+        __be32 nfserr;
+
+        spin_lock(&fp->fi_lock);
+        nfserr = nfsd4_recall_conflict(ls);
+        if (nfserr)
+                goto out;
+        spin_lock(&ls->ls_lock);
+        list_for_each_entry(lp, &ls->ls_layouts, lo_perstate) {
+                if (layouts_try_merge(&lp->lo_seg, seg))
+                        goto done;
+        }
+        spin_unlock(&ls->ls_lock);
+        spin_unlock(&fp->fi_lock);
+
+        new = kmem_cache_alloc(nfs4_layout_cache, GFP_KERNEL);
+        if (!new)
+                return nfserr_jukebox;
+        memcpy(&new->lo_seg, seg, sizeof(lp->lo_seg));
+        new->lo_state = ls;
+
+        spin_lock(&fp->fi_lock);
+        nfserr = nfsd4_recall_conflict(ls);
+        if (nfserr)
+                goto out;
+        spin_lock(&ls->ls_lock);
+        list_for_each_entry(lp, &ls->ls_layouts, lo_perstate) {
+                if (layouts_try_merge(&lp->lo_seg, seg))
+                        goto done;
+        }
+
+        atomic_inc(&ls->ls_stid.sc_count);
+        list_add_tail(&new->lo_perstate, &ls->ls_layouts);
+        new = NULL;
+done:
+        update_stateid(&ls->ls_stid.sc_stateid);
+        memcpy(&lgp->lg_sid, &ls->ls_stid.sc_stateid, sizeof(stateid_t));
+        spin_unlock(&ls->ls_lock);
+out:
+        spin_unlock(&fp->fi_lock);
+        if (new)
+                kmem_cache_free(nfs4_layout_cache, new);
+        return nfserr;
+}
+
+static void
+nfsd4_free_layouts(struct list_head *reaplist)
+{
+        while (!list_empty(reaplist)) {
+                struct nfs4_layout *lp = list_first_entry(reaplist,
+                                struct nfs4_layout, lo_perstate);
+
+                list_del(&lp->lo_perstate);
+                nfs4_put_stid(&lp->lo_state->ls_stid);
+                kmem_cache_free(nfs4_layout_cache, lp);
+        }
+}
+
+static void
+nfsd4_return_file_layout(struct nfs4_layout *lp, struct nfsd4_layout_seg *seg,
+                struct list_head *reaplist)
+{
+        struct nfsd4_layout_seg *lo = &lp->lo_seg;
+        u64 end = layout_end(lo);
+
+        if (seg->offset <= lo->offset) {
+                if (layout_end(seg) >= end) {
+                        list_move_tail(&lp->lo_perstate, reaplist);
+                        return;
+                }
+                end = seg->offset;
+        } else {
+                /* retain the whole layout segment on a split. */
+                if (layout_end(seg) < end) {
+                        dprintk("%s: split not supported\n", __func__);
+                        return;
+                }
+
+                lo->offset = layout_end(seg);
+        }
+
+        layout_update_len(lo, end);
+}
+
+__be32
+nfsd4_return_file_layouts(struct svc_rqst *rqstp,
+                struct nfsd4_compound_state *cstate,
+                struct nfsd4_layoutreturn *lrp)
+{
+        struct nfs4_layout_stateid *ls;
+        struct nfs4_layout *lp, *n;
+        LIST_HEAD(reaplist);
+        __be32 nfserr;
+        int found = 0;
+
+        nfserr = nfsd4_preprocess_layout_stateid(rqstp, cstate, &lrp->lr_sid,
+                                                false, lrp->lr_layout_type,
+                                                &ls);
+        if (nfserr) {
+                trace_layout_return_lookup_fail(&lrp->lr_sid);
+                return nfserr;
+        }
+
+        spin_lock(&ls->ls_lock);
+        list_for_each_entry_safe(lp, n, &ls->ls_layouts, lo_perstate) {
+                if (layouts_overlapping(lp, &lrp->lr_seg)) {
+                        nfsd4_return_file_layout(lp, &lrp->lr_seg, &reaplist);
+                        found++;
+                }
+        }
+        if (!list_empty(&ls->ls_layouts)) {
+                if (found) {
+                        update_stateid(&ls->ls_stid.sc_stateid);
+                        memcpy(&lrp->lr_sid, &ls->ls_stid.sc_stateid,
+                                sizeof(stateid_t));
+                }
+                lrp->lrs_present = 1;
+        } else {
+                trace_layoutstate_unhash(&ls->ls_stid.sc_stateid);
+                nfs4_unhash_stid(&ls->ls_stid);
+                lrp->lrs_present = 0;
+        }
+        spin_unlock(&ls->ls_lock);
+
+        nfs4_put_stid(&ls->ls_stid);
+        nfsd4_free_layouts(&reaplist);
+        return nfs_ok;
+}
+
+__be32
+nfsd4_return_client_layouts(struct svc_rqst *rqstp,
+                struct nfsd4_compound_state *cstate,
+                struct nfsd4_layoutreturn *lrp)
+{
+        struct nfs4_layout_stateid *ls, *n;
+        struct nfs4_client *clp = cstate->clp;
+        struct nfs4_layout *lp, *t;
+        LIST_HEAD(reaplist);
+
+        lrp->lrs_present = 0;
+
+        spin_lock(&clp->cl_lock);
+        list_for_each_entry_safe(ls, n, &clp->cl_lo_states, ls_perclnt) {
+                if (lrp->lr_return_type == RETURN_FSID &&
+                    !fh_fsid_match(&ls->ls_stid.sc_file->fi_fhandle,
+                                   &cstate->current_fh.fh_handle))
+                        continue;
+
+                spin_lock(&ls->ls_lock);
+                list_for_each_entry_safe(lp, t, &ls->ls_layouts, lo_perstate) {
+                        if (lrp->lr_seg.iomode == IOMODE_ANY ||
+                            lrp->lr_seg.iomode == lp->lo_seg.iomode)
+                                list_move_tail(&lp->lo_perstate, &reaplist);
+                }
+                spin_unlock(&ls->ls_lock);
+        }
+        spin_unlock(&clp->cl_lock);
+
+        nfsd4_free_layouts(&reaplist);
+        return 0;
+}
+
+static void
+nfsd4_return_all_layouts(struct nfs4_layout_stateid *ls,
+                struct list_head *reaplist)
+{
+        spin_lock(&ls->ls_lock);
+        list_splice_init(&ls->ls_layouts, reaplist);
+        spin_unlock(&ls->ls_lock);
+}
+
+void
+nfsd4_return_all_client_layouts(struct nfs4_client *clp)
+{
+        struct nfs4_layout_stateid *ls, *n;
+        LIST_HEAD(reaplist);
+
+        spin_lock(&clp->cl_lock);
+        list_for_each_entry_safe(ls, n, &clp->cl_lo_states, ls_perclnt)
+                nfsd4_return_all_layouts(ls, &reaplist);
+        spin_unlock(&clp->cl_lock);
+
+        nfsd4_free_layouts(&reaplist);
+}
+
+void
+nfsd4_return_all_file_layouts(struct nfs4_client *clp, struct nfs4_file *fp)
+{
+        struct nfs4_layout_stateid *ls, *n;
+        LIST_HEAD(reaplist);
+
+        spin_lock(&fp->fi_lock);
+        list_for_each_entry_safe(ls, n, &fp->fi_lo_states, ls_perfile) {
+                if (ls->ls_stid.sc_client == clp)
+                        nfsd4_return_all_layouts(ls, &reaplist);
+        }
+        spin_unlock(&fp->fi_lock);
+
+        nfsd4_free_layouts(&reaplist);
+}
+
+static void
+nfsd4_cb_layout_fail(struct nfs4_layout_stateid *ls)
+{
+        struct nfs4_client *clp = ls->ls_stid.sc_client;
+        char addr_str[INET6_ADDRSTRLEN];
+        static char *envp[] = {
+                "HOME=/",
+                "TERM=linux",
+                "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
+                NULL
+        };
+        char *argv[8];
+        int error;
+
+        rpc_ntop((struct sockaddr *)&clp->cl_addr, addr_str, sizeof(addr_str));
+
+        nfsd4_cb_layout_fail(ls);
+
+        printk(KERN_WARNING
+                "nfsd: client %s failed to respond to layout recall. "
+                "  Fencing..\n", addr_str);
+
+        argv[0] = "/sbin/nfsd-recall-failed";
+        argv[1] = addr_str;
+        argv[2] = ls->ls_file->f_path.mnt->mnt_sb->s_id;
+        argv[3] = NULL;
+
+        error = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
+        if (error) {
+                printk(KERN_ERR "nfsd: fence failed for client %s: %d!\n",
+                        addr_str, error);
+        }
+}
+
+static int
+nfsd4_cb_layout_done(struct nfsd4_callback *cb, struct rpc_task *task)
+{
+        struct nfs4_layout_stateid *ls =
+                container_of(cb, struct nfs4_layout_stateid, ls_recall);
+        LIST_HEAD(reaplist);
+
+        switch (task->tk_status) {
+        case 0:
+                return 1;
+        case -NFS4ERR_NOMATCHING_LAYOUT:
+                trace_layout_recall_done(&ls->ls_stid.sc_stateid);
+                task->tk_status = 0;
+                return 1;
+        case -NFS4ERR_DELAY:
+                /* Poll the client until it's done with the layout */
+                /* FIXME: cap number of retries.
+                 * The pnfs standard states that we need to only expire
+                 * the client after at-least "lease time" .eg lease-time * 2
+                 * when failing to communicate a recall
+                 */
+                rpc_delay(task, HZ/100); /* 10 mili-seconds */
+                return 0;
+        default:
+                /*
+                 * Unknown error or non-responding client, we'll need to fence.
+                 */
+                nfsd4_cb_layout_fail(ls);
+                return -1;
+        }
+}
+
+static void
+nfsd4_cb_layout_release(struct nfsd4_callback *cb)
+{
+        struct nfs4_layout_stateid *ls =
+                container_of(cb, struct nfs4_layout_stateid, ls_recall);
+        LIST_HEAD(reaplist);
+
+        trace_layout_recall_release(&ls->ls_stid.sc_stateid);
+
+        nfsd4_return_all_layouts(ls, &reaplist);
+        nfsd4_free_layouts(&reaplist);
+        nfs4_put_stid(&ls->ls_stid);
+}
+
+static struct nfsd4_callback_ops nfsd4_cb_layout_ops = {
+        .done           = nfsd4_cb_layout_done,
+        .release        = nfsd4_cb_layout_release,
+};
+
+static bool
+nfsd4_layout_lm_break(struct file_lock *fl)
+{
+        /*
+         * We don't want the locks code to timeout the lease for us;
+         * we'll remove it ourself if a layout isn't returned
+         * in time:
+         */
+        fl->fl_break_time = 0;
+        nfsd4_recall_file_layout(fl->fl_owner);
+        return false;
+}
+
+static int
+nfsd4_layout_lm_change(struct file_lock *onlist, int arg,
+                struct list_head *dispose)
+{
+        BUG_ON(!(arg & F_UNLCK));
+        return lease_modify(onlist, arg, dispose);
+}
+
+static const struct lock_manager_operations nfsd4_layouts_lm_ops = {
+        .lm_break       = nfsd4_layout_lm_break,
+        .lm_change      = nfsd4_layout_lm_change,
+};
+
+int
+nfsd4_init_pnfs(void)
+{
+        int i;
+
+        for (i = 0; i < DEVID_HASH_SIZE; i++)
+                INIT_LIST_HEAD(&nfsd_devid_hash[i]);
+
+        nfs4_layout_cache = kmem_cache_create("nfs4_layout",
+                        sizeof(struct nfs4_layout), 0, 0, NULL);
+        if (!nfs4_layout_cache)
+                return -ENOMEM;
+
+        nfs4_layout_stateid_cache = kmem_cache_create("nfs4_layout_stateid",
+                        sizeof(struct nfs4_layout_stateid), 0, 0, NULL);
+        if (!nfs4_layout_stateid_cache) {
+                kmem_cache_destroy(nfs4_layout_cache);
+                return -ENOMEM;
+        }
+        return 0;
+}
+
+void
+nfsd4_exit_pnfs(void)
+{
+        int i;
+
+        kmem_cache_destroy(nfs4_layout_cache);
+        kmem_cache_destroy(nfs4_layout_stateid_cache);
+
+        for (i = 0; i < DEVID_HASH_SIZE; i++) {
+                struct nfsd4_deviceid_map *map, *n;
+
+                list_for_each_entry_safe(map, n, &nfsd_devid_hash[i], hash)
+                        kfree(map);
+        }
+}