nfsd4: look up stateid's per clientid

Use a separate stateid idr per client, and lookup a stateid by first
finding the client, then looking up the stateid relative to that client.

Also some minor refactoring.

This allows us to improve error returns: we can return expired when the
clientid is not found and bad_stateid when the clientid is found but not
the stateid, as opposed to returning expired for both cases.

I hope this will also help to replace the state lock mostly by a
per-client lock, but that hasn't been done yet.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

3 files changed, 54 insertions, 65 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index daf75fa4c027..931155f51ecc 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -32,7 +32,6 @@
 *
 */
 
-#include <linux/idr.h>
 #include <linux/file.h>
 #include <linux/fs.h>
 #include <linux/slab.h>
@@ -149,8 +148,6 @@ static struct list_head	open_ownerstr_hashtbl[OPEN_OWNER_HASH_SIZE];
 #define FILE_HASH_BITS                   8
 #define FILE_HASH_SIZE                  (1 << FILE_HASH_BITS)
 
-struct idr stateids;
-
 static unsigned int file_hashval(struct inode *ino)
 {
         /* XXX: why are we hashing on inode pointer, anyway? */
@@ -209,13 +206,14 @@ static void nfs4_file_put_access(struct nfs4_file *fp, int oflag)
 static inline int get_new_stid(struct nfs4_stid *stid)
 {
         static int min_stateid = 0;
+        struct idr *stateids = &stid->sc_client->cl_stateids;
         int new_stid;
         int error;
 
-        if (!idr_pre_get(&stateids, GFP_KERNEL))
+        if (!idr_pre_get(stateids, GFP_KERNEL))
                 return -ENOMEM;
 
-        error = idr_get_new_above(&stateids, stid, min_stateid, &new_stid);
+        error = idr_get_new_above(stateids, stid, min_stateid, &new_stid);
         /*
          * All this code is currently serialized; the preallocation
          * above should still be ours:
@@ -324,7 +322,9 @@ static void nfs4_put_deleg_lease(struct nfs4_file *fp)
 
 static void unhash_stid(struct nfs4_stid *s)
 {
-        idr_remove(&stateids, s->sc_stateid.si_opaque.so_id);
+        struct idr *stateids = &s->sc_client->cl_stateids;
+
+        idr_remove(stateids, s->sc_stateid.si_opaque.so_id);
 }
 
 /* Called under the state lock. */
@@ -1126,16 +1126,16 @@ static void gen_confirm(struct nfs4_client *clp)
         *p++ = i++;
 }
 
-static struct nfs4_stid *find_stateid(stateid_t *t)
+static struct nfs4_stid *find_stateid(struct nfs4_client *cl, stateid_t *t)
 {
-        return idr_find(&stateids, t->si_opaque.so_id);
+        return idr_find(&cl->cl_stateids, t->si_opaque.so_id);
 }
 
-static struct nfs4_stid *find_stateid_by_type(stateid_t *t, char typemask)
+static struct nfs4_stid *find_stateid_by_type(struct nfs4_client *cl, stateid_t *t, char typemask)
 {
         struct nfs4_stid *s;
 
-        s = find_stateid(t);
+        s = find_stateid(cl, t);
         if (!s)
                 return NULL;
         if (typemask & s->sc_type)
@@ -1143,16 +1143,6 @@ static struct nfs4_stid *find_stateid_by_type(stateid_t *t, char typemask)
         return NULL;
 }
 
-static struct nfs4_ol_stateid *find_ol_stateid_by_type(stateid_t *t, char typemask)
-{
-        struct nfs4_stid *s;
-
-        s = find_stateid_by_type(t, typemask);
-        if (!s)
-                return NULL;
-        return openlockstateid(s);
-}
-
 static struct nfs4_client *create_client(struct xdr_netobj name, char *recdir,
                 struct svc_rqst *rqstp, nfs4_verifier *verf)
 {
@@ -1175,6 +1165,7 @@ static struct nfs4_client *create_client(struct xdr_netobj name, char *recdir,
                 }
         }
 
+        idr_init(&clp->cl_stateids);
         memcpy(clp->cl_recdir, recdir, HEXDIR_LEN);
         atomic_set(&clp->cl_refcount, 0);
         clp->cl_cb_state = NFSD4_CB_UNKNOWN;
@@ -2611,24 +2602,24 @@ static int share_access_to_flags(u32 share_access)
         return share_access == NFS4_SHARE_ACCESS_READ ? RD_STATE : WR_STATE;
 }
 
-static struct nfs4_delegation *find_deleg_stateid(stateid_t *s)
+static struct nfs4_delegation *find_deleg_stateid(struct nfs4_client *cl, stateid_t *s)
 {
         struct nfs4_stid *ret;
 
-        ret = find_stateid_by_type(s, NFS4_DELEG_STID);
+        ret = find_stateid_by_type(cl, s, NFS4_DELEG_STID);
         if (!ret)
                 return NULL;
         return delegstateid(ret);
 }
 
 static __be32
-nfs4_check_deleg(struct nfs4_file *fp, struct nfsd4_open *open,
+nfs4_check_deleg(struct nfs4_client *cl, struct nfs4_file *fp, struct nfsd4_open *open,
                 struct nfs4_delegation **dp)
 {
         int flags;
         __be32 status = nfserr_bad_stateid;
 
-        *dp = find_deleg_stateid(&open->op_delegate_stateid);
+        *dp = find_deleg_stateid(cl, &open->op_delegate_stateid);
         if (*dp == NULL)
                 goto out;
         flags = share_access_to_flags(open->op_share_access);
@@ -2920,6 +2911,7 @@ __be32
 nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
 {
         struct nfsd4_compoundres *resp = rqstp->rq_resp;
+        struct nfs4_client *cl = open->op_openowner->oo_owner.so_client;
         struct nfs4_file *fp = NULL;
         struct inode *ino = current_fh->fh_dentry->d_inode;
         struct nfs4_ol_stateid *stp = NULL;
@@ -2939,7 +2931,7 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
         if (fp) {
                 if ((status = nfs4_check_open(fp, open, &stp)))
                         goto out;
-                status = nfs4_check_deleg(fp, open, &dp);
+                status = nfs4_check_deleg(cl, fp, open, &dp);
                 if (status)
                         goto out;
         } else {
@@ -3256,7 +3248,7 @@ static int check_stateid_generation(stateid_t *in, stateid_t *ref, bool has_sess
         return nfserr_old_stateid;
 }
 
-__be32 nfs4_validate_stateid(stateid_t *stateid)
+__be32 nfs4_validate_stateid(struct nfs4_client *cl, stateid_t *stateid)
 {
         struct nfs4_stid *s;
         struct nfs4_ol_stateid *ols;
@@ -3265,7 +3257,7 @@ __be32 nfs4_validate_stateid(stateid_t *stateid)
         if (STALE_STATEID(stateid))
                 return nfserr_stale_stateid;
 
-        s = find_stateid(stateid);
+        s = find_stateid(cl, stateid);
         if (!s)
                  return nfserr_stale_stateid;
         status = check_stateid_generation(stateid, &s->sc_stateid, 1);
@@ -3280,6 +3272,24 @@ __be32 nfs4_validate_stateid(stateid_t *stateid)
         return nfs_ok;
 }
 
+static __be32 nfsd4_lookup_stateid(stateid_t *stateid, unsigned char typemask, struct nfs4_stid **s)
+{
+        struct nfs4_client *cl;
+
+        if (ZERO_STATEID(stateid) || ONE_STATEID(stateid))
+                return nfserr_bad_stateid;
+        if (STALE_STATEID(stateid))
+                return nfserr_stale_stateid;
+        cl = find_confirmed_client(&stateid->si_opaque.so_clid);
+        if (!cl)
+                return nfserr_expired;
+        *s = find_stateid_by_type(cl, stateid, typemask);
+        if (!*s)
+                return nfserr_bad_stateid;
+        return nfs_ok;
+
+}
+
 /*
 * Checks for stateid operations
 */
@@ -3303,18 +3313,9 @@ nfs4_preprocess_stateid_op(struct nfsd4_compound_state *cstate,
         if (ZERO_STATEID(stateid) || ONE_STATEID(stateid))
                 return check_special_stateids(current_fh, stateid, flags);
 
-        status = nfserr_stale_stateid;
-        if (STALE_STATEID(stateid)) 
-                goto out;
-
-        /*
-         * We assume that any stateid that has the current boot time,
-         * but that we can't find, is expired:
-         */
-        status = nfserr_expired;
-        s = find_stateid(stateid);
-        if (!s)
-                goto out;
+        status = nfsd4_lookup_stateid(stateid, NFS4_DELEG_STID|NFS4_OPEN_STID|NFS4_LOCK_STID, &s);
+        if (status)
+                return status;
         status = check_stateid_generation(stateid, &s->sc_stateid, nfsd4_has_session(cstate));
         if (status)
                 goto out;
@@ -3384,10 +3385,11 @@ nfsd4_free_stateid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 {
         stateid_t *stateid = &free_stateid->fr_stateid;
         struct nfs4_stid *s;
+        struct nfs4_client *cl = cstate->session->se_client;
         __be32 ret = nfserr_bad_stateid;
 
         nfs4_lock_state();
-        s = find_stateid(stateid);
+        s = find_stateid(cl, stateid);
         if (!s)
                 goto out;
         switch (s->sc_type) {
@@ -3419,15 +3421,6 @@ setlkflg (int type)
                 RD_STATE : WR_STATE;
 }
 
-static __be32 nfs4_nospecial_stateid_checks(stateid_t *stateid)
-{
-        if (ZERO_STATEID(stateid) || ONE_STATEID(stateid))
-                return nfserr_bad_stateid;
-        if (STALE_STATEID(stateid))
-                return nfserr_stale_stateid;
-        return nfs_ok;
-}
-
 static __be32 nfs4_seqid_op_checks(struct nfsd4_compound_state *cstate, stateid_t *stateid, u32 seqid, struct nfs4_ol_stateid *stp)
 {
         struct svc_fh *current_fh = &cstate->current_fh;
@@ -3458,17 +3451,16 @@ nfs4_preprocess_seqid_op(struct nfsd4_compound_state *cstate, u32 seqid,
                          struct nfs4_ol_stateid **stpp)
 {
         __be32 status;
+        struct nfs4_stid *s;
 
         dprintk("NFSD: %s: seqid=%d stateid = " STATEID_FMT "\n", __func__,
                 seqid, STATEID_VAL(stateid));
 
         *stpp = NULL;
-        status = nfs4_nospecial_stateid_checks(stateid);
+        status = nfsd4_lookup_stateid(stateid, typemask, &s);
         if (status)
                 return status;
-        *stpp = find_ol_stateid_by_type(stateid, typemask);
-        if (*stpp == NULL)
-                return nfserr_expired;
+        *stpp = openlockstateid(s);
         cstate->replay_owner = (*stpp)->st_stateowner;
         renew_client((*stpp)->st_stateowner->so_client);
 
@@ -3673,6 +3665,7 @@ nfsd4_delegreturn(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 {
         struct nfs4_delegation *dp;
         stateid_t *stateid = &dr->dr_stateid;
+        struct nfs4_stid *s;
         struct inode *inode;
         __be32 status;
 
@@ -3681,16 +3674,10 @@ nfsd4_delegreturn(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
         inode = cstate->current_fh.fh_dentry->d_inode;
 
         nfs4_lock_state();
-        status = nfserr_bad_stateid;
-        if (ZERO_STATEID(stateid) || ONE_STATEID(stateid))
-                goto out;
-        status = nfserr_stale_stateid;
-        if (STALE_STATEID(stateid))
-                goto out;
-        status = nfserr_expired;
-        dp = find_deleg_stateid(stateid);
-        if (!dp)
+        status = nfsd4_lookup_stateid(stateid, NFS4_DELEG_STID, &s);
+        if (status)
                 goto out;
+        dp = delegstateid(s);
         status = check_stateid_generation(stateid, &dp->dl_stid.sc_stateid, nfsd4_has_session(cstate));
         if (status)
                 goto out;
@@ -4409,7 +4396,6 @@ nfs4_state_init(void)
         for (i = 0; i < OPEN_OWNER_HASH_SIZE; i++) {
                 INIT_LIST_HEAD(&open_ownerstr_hashtbl[i]);
         }
-        idr_init(&stateids);
         for (i = 0; i < LOCK_HASH_SIZE; i++) {
                 INIT_LIST_HEAD(&lock_ownerstr_hashtbl[i]);
         }
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 2429fffa31dd..5779acde7e70 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -3287,6 +3287,7 @@ nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, int nfserr,
                           struct nfsd4_test_stateid *test_stateid)
 {
         struct nfsd4_compoundargs *argp;
+        struct nfs4_client *cl = resp->cstate.session->se_client;
         stateid_t si;
         __be32 *p;
         int i;
@@ -3302,7 +3303,7 @@ nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, int nfserr,
         nfs4_lock_state();
         for (i = 0; i < test_stateid->ts_num_ids; i++) {
                 nfsd4_decode_stateid(argp, &si);
-                valid = nfs4_validate_stateid(&si);
+                valid = nfs4_validate_stateid(cl, &si);
                 RESERVE_SPACE(4);
                 *p++ = htonl(valid);
                 resp->p = p;
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 55a4d6a108a2..13f6f9f5ceec 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -35,6 +35,7 @@
 #ifndef _NFSD4_STATE_H
 #define _NFSD4_STATE_H
 
+#include <linux/idr.h>
 #include <linux/sunrpc/svc_xprt.h>
 #include <linux/nfsd/nfsfh.h>
 #include "nfsfh.h"
@@ -231,6 +232,7 @@ struct nfs4_client {
         struct list_head        cl_idhash;      /* hash by cl_clientid.id */
         struct list_head        cl_strhash;     /* hash by cl_name */
         struct list_head        cl_openowners;
+        struct idr              cl_stateids;    /* stateid lookup */
         struct list_head        cl_delegations;
         struct list_head        cl_lru;         /* tail queue */
         struct xdr_netobj       cl_name;        /* id generated by client */
@@ -508,7 +510,7 @@ extern void nfsd4_recdir_purge_old(void);
 extern int nfsd4_create_clid_dir(struct nfs4_client *clp);
 extern void nfsd4_remove_clid_dir(struct nfs4_client *clp);
 extern void release_session_client(struct nfsd4_session *);
-extern __be32 nfs4_validate_stateid(stateid_t *);
+extern __be32 nfs4_validate_stateid(struct nfs4_client *, stateid_t *);
 extern void nfsd4_purge_closed_stateid(struct nfs4_stateowner *);
 
 #endif   /* NFSD4_STATE_H */