nfsd: allow layout state to be admin-revoked.

When there is layout state on a filesystem that is being "unlocked" that
is now revoked, which involves closing the nfsd_file and releasing the
vfs lease.

To avoid races, ->ls_file can now be accessed either:
 - under ->fi_lock for the state's sc_file or
 - under rcu_read_lock() if nfsd_file_get() is used.
To support this, ->fence_client and nfsd4_cb_layout_fail() now take a
second argument being the nfsd_file.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/blocklayout.c b/fs/nfsd/blocklayout.c
index 46fd74d91ea929d31d173deefe485372b80cd8b4..3c040c81c77d019c88f0694463da10a04487b4ce 100644 (file)
--- a/fs/nfsd/blocklayout.c
+++ b/fs/nfsd/blocklayout.c
@@ -328,10 +328,10 @@ nfsd4_scsi_proc_layoutcommit(struct inode *inode,
 }
 
 static void
-nfsd4_scsi_fence_client(struct nfs4_layout_stateid *ls)
+nfsd4_scsi_fence_client(struct nfs4_layout_stateid *ls, struct nfsd_file *file)
 {
        struct nfs4_client *clp = ls->ls_stid.sc_client;
-       struct block_device *bdev = ls->ls_file->nf_file->f_path.mnt->mnt_sb->s_bdev;
+       struct block_device *bdev = file->nf_file->f_path.mnt->mnt_sb->s_bdev;
 
        bdev->bd_disk->fops->pr_ops->pr_preempt(bdev, NFSD_MDS_PR_KEY,
                        nfsd4_scsi_pr_key(clp), 0, true);

diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c
index 857b822450b4fee85f6aac4e44106968c50f5c1a..1cfd61db247297ca77fcf92e33374be817c9bffd 100644 (file)
--- a/fs/nfsd/nfs4layouts.c
+++ b/fs/nfsd/nfs4layouts.c
@@ -152,6 +152,23 @@ void nfsd4_setup_layout_type(struct svc_export *exp)
 #endif
 }
 
+void nfsd4_close_layout(struct nfs4_layout_stateid *ls)
+{
+       struct nfsd_file *fl;
+
+       spin_lock(&ls->ls_stid.sc_file->fi_lock);
+       fl = ls->ls_file;
+       ls->ls_file = NULL;
+       spin_unlock(&ls->ls_stid.sc_file->fi_lock);
+
+       if (fl) {
+               if (!nfsd4_layout_ops[ls->ls_layout_type]->disable_recalls)
+                       vfs_setlease(fl->nf_file, F_UNLCK, NULL,
+                                    (void **)&ls);
+               nfsd_file_put(fl);
+       }
+}
+
 static void
 nfsd4_free_layout_stateid(struct nfs4_stid *stid)
 {
@@ -169,9 +186,7 @@ nfsd4_free_layout_stateid(struct nfs4_stid *stid)
        list_del_init(&ls->ls_perfile);
        spin_unlock(&fp->fi_lock);
 
-       if (!nfsd4_layout_ops[ls->ls_layout_type]->disable_recalls)
-               vfs_setlease(ls->ls_file->nf_file, F_UNLCK, NULL, (void **)&ls);
-       nfsd_file_put(ls->ls_file);
+       nfsd4_close_layout(ls);
 
        if (ls->ls_recalled)
                atomic_dec(&ls->ls_stid.sc_file->fi_lo_recalls);
@@ -605,7 +620,7 @@ nfsd4_return_all_file_layouts(struct nfs4_client *clp, struct nfs4_file *fp)
 }
 
 static void
-nfsd4_cb_layout_fail(struct nfs4_layout_stateid *ls)
+nfsd4_cb_layout_fail(struct nfs4_layout_stateid *ls, struct nfsd_file *file)
 {
        struct nfs4_client *clp = ls->ls_stid.sc_client;
        char addr_str[INET6_ADDRSTRLEN];
@@ -627,7 +642,7 @@ nfsd4_cb_layout_fail(struct nfs4_layout_stateid *ls)
 
        argv[0] = (char *)nfsd_recall_failed;
        argv[1] = addr_str;
-       argv[2] = ls->ls_file->nf_file->f_path.mnt->mnt_sb->s_id;
+       argv[2] = file->nf_file->f_path.mnt->mnt_sb->s_id;
        argv[3] = NULL;
 
        error = call_usermodehelper(nfsd_recall_failed, argv, envp,
@@ -657,6 +672,7 @@ nfsd4_cb_layout_done(struct nfsd4_callback *cb, struct rpc_task *task)
        struct nfsd_net *nn;
        ktime_t now, cutoff;
        const struct nfsd4_layout_ops *ops;
+       struct nfsd_file *fl;
 
        trace_nfsd_cb_layout_done(&ls->ls_stid.sc_stateid, task);
        switch (task->tk_status) {
@@ -688,12 +704,17 @@ nfsd4_cb_layout_done(struct nfsd4_callback *cb, struct rpc_task *task)
                 * Unknown error or non-responding client, we'll need to fence.
                 */
                trace_nfsd_layout_recall_fail(&ls->ls_stid.sc_stateid);
-
-               ops = nfsd4_layout_ops[ls->ls_layout_type];
-               if (ops->fence_client)
-                       ops->fence_client(ls);
-               else
-                       nfsd4_cb_layout_fail(ls);
+               rcu_read_lock();
+               fl = nfsd_file_get(ls->ls_file);
+               rcu_read_unlock();
+               if (fl) {
+                       ops = nfsd4_layout_ops[ls->ls_layout_type];
+                       if (ops->fence_client)
+                               ops->fence_client(ls, fl);
+                       else
+                               nfsd4_cb_layout_fail(ls, fl);
+                       nfsd_file_put(fl);
+               }
                return 1;
        case -NFS4ERR_NOMATCHING_LAYOUT:
                trace_nfsd_layout_recall_done(&ls->ls_stid.sc_stateid);

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index d418c28cd77a061321f8d42012c4b0f4751a225a..4464e4d8aef520759ce3af8fd51a5fd844849b7b 100644 (file)
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1721,7 +1721,7 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
        unsigned int idhashval;
        unsigned int sc_types;
 
-       sc_types = SC_TYPE_OPEN | SC_TYPE_LOCK | SC_TYPE_DELEG;
+       sc_types = SC_TYPE_OPEN | SC_TYPE_LOCK | SC_TYPE_DELEG | SC_TYPE_LAYOUT;
 
        spin_lock(&nn->client_lock);
        for (idhashval = 0; idhashval < CLIENT_HASH_MASK; idhashval++) {
@@ -1734,6 +1734,7 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
                        if (stid) {
                                struct nfs4_ol_stateid *stp;
                                struct nfs4_delegation *dp;
+                               struct nfs4_layout_stateid *ls;
 
                                spin_unlock(&nn->client_lock);
                                switch (stid->sc_type) {
@@ -1789,6 +1790,10 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
                                        if (dp)
                                                revoke_delegation(dp);
                                        break;
+                               case SC_TYPE_LAYOUT:
+                                       ls = layoutstateid(stid);
+                                       nfsd4_close_layout(ls);
+                                       break;
                                }
                                nfs4_put_stid(stid);
                                spin_lock(&nn->client_lock);
@@ -2868,7 +2873,6 @@ static int nfs4_show_layout(struct seq_file *s, struct nfs4_stid *st)
        struct nfsd_file *file;
 
        ls = container_of(st, struct nfs4_layout_stateid, ls_stid);
-       file = ls->ls_file;
 
        seq_puts(s, "- ");
        nfs4_show_stateid(s, &st->sc_stateid);
@@ -2876,12 +2880,15 @@ static int nfs4_show_layout(struct seq_file *s, struct nfs4_stid *st)
 
        /* XXX: What else would be useful? */
 
+       spin_lock(&ls->ls_stid.sc_file->fi_lock);
+       file = ls->ls_file;
        if (file) {
                seq_puts(s, ", ");
                nfs4_show_superblock(s, file);
                seq_puts(s, ", ");
                nfs4_show_fname(s, file);
        }
+       spin_unlock(&ls->ls_stid.sc_file->fi_lock);
        if (st->sc_status & SC_STATUS_ADMIN_REVOKED)
                seq_puts(s, ", admin-revoked");
        seq_puts(s, " }\n");

diff --git a/fs/nfsd/pnfs.h b/fs/nfsd/pnfs.h
index de1e0dfed06a23d378b8a9a2bfaebfbb3217aab7..925817f669176cc1ff3b7a1ddfc32429ee82745c 100644 (file)
--- a/fs/nfsd/pnfs.h
+++ b/fs/nfsd/pnfs.h
@@ -37,7 +37,8 @@ struct nfsd4_layout_ops {
        __be32 (*proc_layoutcommit)(struct inode *inode,
                        struct nfsd4_layoutcommit *lcp);
 
-       void (*fence_client)(struct nfs4_layout_stateid *ls);
+       void (*fence_client)(struct nfs4_layout_stateid *ls,
+                            struct nfsd_file *file);
 };
 
 extern const struct nfsd4_layout_ops *nfsd4_layout_ops[];
@@ -72,11 +73,13 @@ void nfsd4_setup_layout_type(struct svc_export *exp);
 void nfsd4_return_all_client_layouts(struct nfs4_client *);
 void nfsd4_return_all_file_layouts(struct nfs4_client *clp,
                struct nfs4_file *fp);
+void nfsd4_close_layout(struct nfs4_layout_stateid *ls);
 int nfsd4_init_pnfs(void);
 void nfsd4_exit_pnfs(void);
 #else
 struct nfs4_client;
 struct nfs4_file;
+struct nfs4_layout_stateid;
 
 static inline void nfsd4_setup_layout_type(struct svc_export *exp)
 {
@@ -89,6 +92,9 @@ static inline void nfsd4_return_all_file_layouts(struct nfs4_client *clp,
                struct nfs4_file *fp)
 {
 }
+static inline void nfsd4_close_layout(struct nfs4_layout_stateid *ls)
+{
+}
 static inline void nfsd4_exit_pnfs(void)
 {
 }