1 files changed, 246 insertions, 169 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 7698172ac0c7..b517a8794400 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -354,6 +354,124 @@ static const struct nfsd4_callback_ops nfsd4_cb_notify_lock_ops = {
 	.release	= nfsd4_cb_notify_lock_release,
 };
 
+/*
+ * We store the NONE, READ, WRITE, and BOTH bits separately in the
+ * st_{access,deny}_bmap field of the stateid, in order to track not
+ * only what share bits are currently in force, but also what
+ * combinations of share bits previous opens have used.  This allows us
+ * to enforce the recommendation of rfc 3530 14.2.19 that the server
+ * return an error if the client attempt to downgrade to a combination
+ * of share bits not explicable by closing some of its previous opens.
+ *
+ * XXX: This enforcement is actually incomplete, since we don't keep
+ * track of access/deny bit combinations; so, e.g., we allow:
+ *
+ *	OPEN allow read, deny write
+ *	OPEN allow both, deny none
+ *	DOWNGRADE allow read, deny none
+ *
+ * which we should reject.
+ */
+static unsigned int
+bmap_to_share_mode(unsigned long bmap)
+{
+	int i;
+	unsigned int access = 0;
+
+	for (i = 1; i < 4; i++) {
+		if (test_bit(i, &bmap))
+			access |= i;
+	}
+	return access;
+}
+
+/* set share access for a given stateid */
+static inline void
+set_access(u32 access, struct nfs4_ol_stateid *stp)
+{
+	unsigned char mask = 1 << access;
+
+	WARN_ON_ONCE(access > NFS4_SHARE_ACCESS_BOTH);
+	stp->st_access_bmap |= mask;
+}
+
+/* clear share access for a given stateid */
+static inline void
+clear_access(u32 access, struct nfs4_ol_stateid *stp)
+{
+	unsigned char mask = 1 << access;
+
+	WARN_ON_ONCE(access > NFS4_SHARE_ACCESS_BOTH);
+	stp->st_access_bmap &= ~mask;
+}
+
+/* test whether a given stateid has access */
+static inline bool
+test_access(u32 access, struct nfs4_ol_stateid *stp)
+{
+	unsigned char mask = 1 << access;
+
+	return (bool)(stp->st_access_bmap & mask);
+}
+
+/* set share deny for a given stateid */
+static inline void
+set_deny(u32 deny, struct nfs4_ol_stateid *stp)
+{
+	unsigned char mask = 1 << deny;
+
+	WARN_ON_ONCE(deny > NFS4_SHARE_DENY_BOTH);
+	stp->st_deny_bmap |= mask;
+}
+
+/* clear share deny for a given stateid */
+static inline void
+clear_deny(u32 deny, struct nfs4_ol_stateid *stp)
+{
+	unsigned char mask = 1 << deny;
+
+	WARN_ON_ONCE(deny > NFS4_SHARE_DENY_BOTH);
+	stp->st_deny_bmap &= ~mask;
+}
+
+/* test whether a given stateid is denying specific access */
+static inline bool
+test_deny(u32 deny, struct nfs4_ol_stateid *stp)
+{
+	unsigned char mask = 1 << deny;
+
+	return (bool)(stp->st_deny_bmap & mask);
+}
+
+static int nfs4_access_to_omode(u32 access)
+{
+	switch (access & NFS4_SHARE_ACCESS_BOTH) {
+	case NFS4_SHARE_ACCESS_READ:
+		return O_RDONLY;
+	case NFS4_SHARE_ACCESS_WRITE:
+		return O_WRONLY;
+	case NFS4_SHARE_ACCESS_BOTH:
+		return O_RDWR;
+	}
+	WARN_ON_ONCE(1);
+	return O_RDONLY;
+}
+
+static inline int
+access_permit_read(struct nfs4_ol_stateid *stp)
+{
+	return test_access(NFS4_SHARE_ACCESS_READ, stp) ||
+		test_access(NFS4_SHARE_ACCESS_BOTH, stp) ||
+		test_access(NFS4_SHARE_ACCESS_WRITE, stp);
+}
+
+static inline int
+access_permit_write(struct nfs4_ol_stateid *stp)
+{
+	return test_access(NFS4_SHARE_ACCESS_WRITE, stp) ||
+		test_access(NFS4_SHARE_ACCESS_BOTH, stp);
+}
+
 static inline struct nfs4_stateowner *
 nfs4_get_stateowner(struct nfs4_stateowner *sop)
 {
@@ -543,14 +661,12 @@ static unsigned int ownerstr_hashval(struct xdr_netobj *ownername)
 #define FILE_HASH_BITS                   8
 #define FILE_HASH_SIZE                  (1 << FILE_HASH_BITS)
 
-static unsigned int nfsd_fh_hashval(struct knfsd_fh *fh)
+static unsigned int file_hashval(struct svc_fh *fh)
 {
-	return jhash2(fh->fh_base.fh_pad, XDR_QUADLEN(fh->fh_size), 0);
-}
+	struct inode *inode = d_inode(fh->fh_dentry);
 
-static unsigned int file_hashval(struct knfsd_fh *fh)
-{
-	return nfsd_fh_hashval(fh) & (FILE_HASH_SIZE - 1);
+	/* XXX: why not (here & in file cache) use inode? */
+	return (unsigned int)hash_long(inode->i_ino, FILE_HASH_BITS);
 }
 
 static struct hlist_head file_hashtbl[FILE_HASH_SIZE];
@@ -1153,108 +1269,6 @@ static unsigned int clientstr_hashval(struct xdr_netobj name)
 }
 
 /*
- * We store the NONE, READ, WRITE, and BOTH bits separately in the
- * st_{access,deny}_bmap field of the stateid, in order to track not
- * only what share bits are currently in force, but also what
- * combinations of share bits previous opens have used.  This allows us
- * to enforce the recommendation of rfc 3530 14.2.19 that the server
- * return an error if the client attempt to downgrade to a combination
- * of share bits not explicable by closing some of its previous opens.
- *
- * XXX: This enforcement is actually incomplete, since we don't keep
- * track of access/deny bit combinations; so, e.g., we allow:
- *
- *	OPEN allow read, deny write
- *	OPEN allow both, deny none
- *	DOWNGRADE allow read, deny none
- *
- * which we should reject.
- */
-static unsigned int
-bmap_to_share_mode(unsigned long bmap) {
-	int i;
-	unsigned int access = 0;
-
-	for (i = 1; i < 4; i++) {
-		if (test_bit(i, &bmap))
-			access |= i;
-	}
-	return access;
-}
-
-/* set share access for a given stateid */
-static inline void
-set_access(u32 access, struct nfs4_ol_stateid *stp)
-{
-	unsigned char mask = 1 << access;
-
-	WARN_ON_ONCE(access > NFS4_SHARE_ACCESS_BOTH);
-	stp->st_access_bmap |= mask;
-}
-
-/* clear share access for a given stateid */
-static inline void
-clear_access(u32 access, struct nfs4_ol_stateid *stp)
-{
-	unsigned char mask = 1 << access;
-
-	WARN_ON_ONCE(access > NFS4_SHARE_ACCESS_BOTH);
-	stp->st_access_bmap &= ~mask;
-}
-
-/* test whether a given stateid has access */
-static inline bool
-test_access(u32 access, struct nfs4_ol_stateid *stp)
-{
-	unsigned char mask = 1 << access;
-
-	return (bool)(stp->st_access_bmap & mask);
-}
-
-/* set share deny for a given stateid */
-static inline void
-set_deny(u32 deny, struct nfs4_ol_stateid *stp)
-{
-	unsigned char mask = 1 << deny;
-
-	WARN_ON_ONCE(deny > NFS4_SHARE_DENY_BOTH);
-	stp->st_deny_bmap |= mask;
-}
-
-/* clear share deny for a given stateid */
-static inline void
-clear_deny(u32 deny, struct nfs4_ol_stateid *stp)
-{
-	unsigned char mask = 1 << deny;
-
-	WARN_ON_ONCE(deny > NFS4_SHARE_DENY_BOTH);
-	stp->st_deny_bmap &= ~mask;
-}
-
-/* test whether a given stateid is denying specific access */
-static inline bool
-test_deny(u32 deny, struct nfs4_ol_stateid *stp)
-{
-	unsigned char mask = 1 << deny;
-
-	return (bool)(stp->st_deny_bmap & mask);
-}
-
-static int nfs4_access_to_omode(u32 access)
-{
-	switch (access & NFS4_SHARE_ACCESS_BOTH) {
-	case NFS4_SHARE_ACCESS_READ:
-		return O_RDONLY;
-	case NFS4_SHARE_ACCESS_WRITE:
-		return O_WRONLY;
-	case NFS4_SHARE_ACCESS_BOTH:
-		return O_RDWR;
-	}
-	WARN_ON_ONCE(1);
-	return O_RDONLY;
-}
-
-/*
  * A stateid that had a deny mode associated with it is being released
  * or downgraded. Recalculate the deny mode on the file.
  */
@@ -3125,6 +3139,7 @@ nfsd4_exchange_id(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 			goto out_nolock;
 		}
 		new->cl_mach_cred = true;
+		break;
 	case SP4_NONE:
 		break;
 	default:				/* checked by xdr code */
@@ -4072,7 +4087,7 @@ static struct nfs4_file *nfsd4_alloc_file(void)
 }
 
 /* OPEN Share state helper functions */
-static void nfsd4_init_file(struct knfsd_fh *fh, unsigned int hashval,
+static void nfsd4_init_file(struct svc_fh *fh, unsigned int hashval,
 				struct nfs4_file *fp)
 {
 	lockdep_assert_held(&state_lock);
@@ -4082,12 +4097,14 @@ static void nfsd4_init_file(struct knfsd_fh *fh, unsigned int hashval,
 	INIT_LIST_HEAD(&fp->fi_stateids);
 	INIT_LIST_HEAD(&fp->fi_delegations);
 	INIT_LIST_HEAD(&fp->fi_clnt_odstate);
-	fh_copy_shallow(&fp->fi_fhandle, fh);
+	fh_copy_shallow(&fp->fi_fhandle, &fh->fh_handle);
 	fp->fi_deleg_file = NULL;
 	fp->fi_had_conflict = false;
 	fp->fi_share_deny = 0;
 	memset(fp->fi_fds, 0, sizeof(fp->fi_fds));
 	memset(fp->fi_access, 0, sizeof(fp->fi_access));
+	fp->fi_aliased = false;
+	fp->fi_inode = d_inode(fh->fh_dentry);
 #ifdef CONFIG_NFSD_PNFS
 	INIT_LIST_HEAD(&fp->fi_lo_states);
 	atomic_set(&fp->fi_lo_recalls, 0);
@@ -4426,13 +4443,13 @@ move_to_close_lru(struct nfs4_ol_stateid *s, struct net *net)
 
 /* search file_hashtbl[] for file */
 static struct nfs4_file *
-find_file_locked(struct knfsd_fh *fh, unsigned int hashval)
+find_file_locked(struct svc_fh *fh, unsigned int hashval)
 {
 	struct nfs4_file *fp;
 
 	hlist_for_each_entry_rcu(fp, &file_hashtbl[hashval], fi_hash,
 				lockdep_is_held(&state_lock)) {
-		if (fh_match(&fp->fi_fhandle, fh)) {
+		if (fh_match(&fp->fi_fhandle, &fh->fh_handle)) {
 			if (refcount_inc_not_zero(&fp->fi_ref))
 				return fp;
 		}
@@ -4440,8 +4457,32 @@ find_file_locked(struct knfsd_fh *fh, unsigned int hashval)
 	return NULL;
 }
 
-struct nfs4_file *
-find_file(struct knfsd_fh *fh)
+static struct nfs4_file *insert_file(struct nfs4_file *new, struct svc_fh *fh,
+				     unsigned int hashval)
+{
+	struct nfs4_file *fp;
+	struct nfs4_file *ret = NULL;
+	bool alias_found = false;
+
+	spin_lock(&state_lock);
+	hlist_for_each_entry_rcu(fp, &file_hashtbl[hashval], fi_hash,
+				 lockdep_is_held(&state_lock)) {
+		if (fh_match(&fp->fi_fhandle, &fh->fh_handle)) {
+			if (refcount_inc_not_zero(&fp->fi_ref))
+				ret = fp;
+		} else if (d_inode(fh->fh_dentry) == fp->fi_inode)
+			fp->fi_aliased = alias_found = true;
+	}
+	if (likely(ret == NULL)) {
+		nfsd4_init_file(fh, hashval, new);
+		new->fi_aliased = alias_found;
+		ret = new;
+	}
+	spin_unlock(&state_lock);
+	return ret;
+}
+
+static struct nfs4_file * find_file(struct svc_fh *fh)
 {
 	struct nfs4_file *fp;
 	unsigned int hashval = file_hashval(fh);
@@ -4453,7 +4494,7 @@ find_file(struct knfsd_fh *fh)
 }
 
 static struct nfs4_file *
-find_or_add_file(struct nfs4_file *new, struct knfsd_fh *fh)
+find_or_add_file(struct nfs4_file *new, struct svc_fh *fh)
 {
 	struct nfs4_file *fp;
 	unsigned int hashval = file_hashval(fh);
@@ -4464,15 +4505,7 @@ find_or_add_file(struct nfs4_file *new, struct knfsd_fh *fh)
 	if (fp)
 		return fp;
 
-	spin_lock(&state_lock);
-	fp = find_file_locked(fh, hashval);
-	if (likely(fp == NULL)) {
-		nfsd4_init_file(fh, hashval, new);
-		fp = new;
-	}
-	spin_unlock(&state_lock);
-
-	return fp;
+	return insert_file(new, fh, hashval);
 }
 
 /*
@@ -4485,7 +4518,7 @@ nfs4_share_conflict(struct svc_fh *current_fh, unsigned int deny_type)
 	struct nfs4_file *fp;
 	__be32 ret = nfs_ok;
 
-	fp = find_file(&current_fh->fh_handle);
+	fp = find_file(current_fh);
 	if (!fp)
 		return ret;
 	/* Check for conflicting share reservations */
@@ -4880,6 +4913,11 @@ static __be32 nfs4_get_vfs_file(struct svc_rqst *rqstp, struct nfs4_file *fp,
 	if (nf)
 		nfsd_file_put(nf);
 
+	status = nfserrno(nfsd_open_break_lease(cur_fh->fh_dentry->d_inode,
+								access));
+	if (status)
+		goto out_put_access;
+
 	status = nfsd4_truncate(rqstp, cur_fh, open);
 	if (status)
 		goto out_put_access;
@@ -4951,6 +4989,65 @@ static struct file_lock *nfs4_alloc_init_lease(struct nfs4_delegation *dp,
 	return fl;
 }
 
+static int nfsd4_check_conflicting_opens(struct nfs4_client *clp,
+					 struct nfs4_file *fp)
+{
+	struct nfs4_ol_stateid *st;
+	struct file *f = fp->fi_deleg_file->nf_file;
+	struct inode *ino = locks_inode(f);
+	int writes;
+
+	writes = atomic_read(&ino->i_writecount);
+	if (!writes)
+		return 0;
+	/*
+	 * There could be multiple filehandles (hence multiple
+	 * nfs4_files) referencing this file, but that's not too
+	 * common; let's just give up in that case rather than
+	 * trying to go look up all the clients using that other
+	 * nfs4_file as well:
+	 */
+	if (fp->fi_aliased)
+		return -EAGAIN;
+	/*
+	 * If there's a close in progress, make sure that we see it
+	 * clear any fi_fds[] entries before we see it decrement
+	 * i_writecount:
+	 */
+	smp_mb__after_atomic();
+
+	if (fp->fi_fds[O_WRONLY])
+		writes--;
+	if (fp->fi_fds[O_RDWR])
+		writes--;
+	if (writes > 0)
+		return -EAGAIN; /* There may be non-NFSv4 writers */
+	/*
+	 * It's possible there are non-NFSv4 write opens in progress,
+	 * but if they haven't incremented i_writecount yet then they
+	 * also haven't called break lease yet; so, they'll break this
+	 * lease soon enough.  So, all that's left to check for is NFSv4
+	 * opens:
+	 */
+	spin_lock(&fp->fi_lock);
+	list_for_each_entry(st, &fp->fi_stateids, st_perfile) {
+		if (st->st_openstp == NULL /* it's an open */ &&
+		    access_permit_write(st) &&
+		    st->st_stid.sc_client != clp) {
+			spin_unlock(&fp->fi_lock);
+			return -EAGAIN;
+		}
+	}
+	spin_unlock(&fp->fi_lock);
+	/*
+	 * There's a small chance that we could be racing with another
+	 * NFSv4 open.  However, any open that hasn't added itself to
+	 * the fi_stateids list also hasn't called break_lease yet; so,
+	 * they'll break this lease soon enough.
+	 */
+	return 0;
+}
+
 static struct nfs4_delegation *
 nfs4_set_delegation(struct nfs4_client *clp, struct svc_fh *fh,
 		    struct nfs4_file *fp, struct nfs4_clnt_odstate *odstate)
@@ -4970,9 +5067,12 @@ nfs4_set_delegation(struct nfs4_client *clp, struct svc_fh *fh,
 
 	nf = find_readable_file(fp);
 	if (!nf) {
-		/* We should always have a readable file here */
-		WARN_ON_ONCE(1);
-		return ERR_PTR(-EBADF);
+		/*
+		 * We probably could attempt another open and get a read
+		 * delegation, but for now, don't bother until the
+		 * client actually sends us one.
+		 */
+		return ERR_PTR(-EAGAIN);
 	}
 	spin_lock(&state_lock);
 	spin_lock(&fp->fi_lock);
@@ -5007,6 +5107,9 @@ nfs4_set_delegation(struct nfs4_client *clp, struct svc_fh *fh,
 		locks_free_lock(fl);
 	if (status)
 		goto out_clnt_odstate;
+	status = nfsd4_check_conflicting_opens(clp, fp);
+	if (status)
+		goto out_unlock;
 
 	spin_lock(&state_lock);
 	spin_lock(&fp->fi_lock);
@@ -5088,17 +5191,6 @@ nfs4_open_delegation(struct svc_fh *fh, struct nfsd4_open *open,
 				goto out_no_deleg;
 			if (!cb_up || !(oo->oo_flags & NFS4_OO_CONFIRMED))
 				goto out_no_deleg;
-			/*
-			 * Also, if the file was opened for write or
-			 * create, there's a good chance the client's
-			 * about to write to it, resulting in an
-			 * immediate recall (since we don't support
-			 * write delegations):
-			 */
-			if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
-				goto out_no_deleg;
-			if (open->op_create == NFS4_OPEN_CREATE)
-				goto out_no_deleg;
 			break;
 		default:
 			goto out_no_deleg;
@@ -5161,7 +5253,7 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
 	 * and check for delegations in the process of being recalled.
 	 * If not found, create the nfs4_file struct
 	 */
-	fp = find_or_add_file(open->op_file, &current_fh->fh_handle);
+	fp = find_or_add_file(open->op_file, current_fh);
 	if (fp != open->op_file) {
 		status = nfs4_check_deleg(cl, open, &dp);
 		if (status)
@@ -5502,21 +5594,6 @@ static inline __be32 nfs4_check_fh(struct svc_fh *fhp, struct nfs4_stid *stp)
 	return nfs_ok;
 }
 
-static inline int
-access_permit_read(struct nfs4_ol_stateid *stp)
-{
-	return test_access(NFS4_SHARE_ACCESS_READ, stp) ||
-		test_access(NFS4_SHARE_ACCESS_BOTH, stp) ||
-		test_access(NFS4_SHARE_ACCESS_WRITE, stp);
-}
-
-static inline int
-access_permit_write(struct nfs4_ol_stateid *stp)
-{
-	return test_access(NFS4_SHARE_ACCESS_WRITE, stp) ||
-		test_access(NFS4_SHARE_ACCESS_BOTH, stp);
-}
-
 static
 __be32 nfs4_check_openmode(struct nfs4_ol_stateid *stp, int flags)
 {
@@ -6288,15 +6365,6 @@ out:
 	return status;
 }
 
-static inline u64
-end_offset(u64 start, u64 len)
-{
-	u64 end;
-
-	end = start + len;
-	return end >= start ? end: NFS4_MAX_UINT64;
-}
-
 /* last octet in a range */
 static inline u64
 last_byte_offset(u64 start, u64 len)
@@ -6865,11 +6933,20 @@ out:
 static __be32 nfsd_test_lock(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file_lock *lock)
 {
 	struct nfsd_file *nf;
-	__be32 err = nfsd_file_acquire(rqstp, fhp, NFSD_MAY_READ, &nf);
-	if (!err) {
-		err = nfserrno(vfs_test_lock(nf->nf_file, lock));
-		nfsd_file_put(nf);
-	}
+	__be32 err;
+
+	err = nfsd_file_acquire(rqstp, fhp, NFSD_MAY_READ, &nf);
+	if (err)
+		return err;
+	fh_lock(fhp); /* to block new leases till after test_lock: */
+	err = nfserrno(nfsd_open_break_lease(fhp->fh_dentry->d_inode,
+							NFSD_MAY_READ));
+	if (err)
+		goto out;
+	err = nfserrno(vfs_test_lock(nf->nf_file, lock));
+out:
+	fh_unlock(fhp);
+	nfsd_file_put(nf);
 	return err;
 }