nfs4state.c

linux 内核源代码

	return NULL;
}

static inline int
nfs4_check_fh(struct svc_fh *fhp, struct nfs4_stateid *stp)
{
	return fhp->fh_dentry->d_inode != stp->st_vfs_file->f_path.dentry->d_inode;
}

static int
STALE_STATEID(stateid_t *stateid)
{
	if (stateid->si_boot == boot_time)
		return 0;
	dprintk("NFSD: stale stateid (%08x/%08x/%08x/%08x)!\n",
		stateid->si_boot, stateid->si_stateownerid, stateid->si_fileid,
		stateid->si_generation);
	return 1;
}

static inline int
access_permit_read(unsigned long access_bmap)
{
	return test_bit(NFS4_SHARE_ACCESS_READ, &access_bmap) ||
		test_bit(NFS4_SHARE_ACCESS_BOTH, &access_bmap) ||
		test_bit(NFS4_SHARE_ACCESS_WRITE, &access_bmap);
}

static inline int
access_permit_write(unsigned long access_bmap)
{
	return test_bit(NFS4_SHARE_ACCESS_WRITE, &access_bmap) ||
		test_bit(NFS4_SHARE_ACCESS_BOTH, &access_bmap);
}

static
__be32 nfs4_check_openmode(struct nfs4_stateid *stp, int flags)
{
        __be32 status = nfserr_openmode;

	if ((flags & WR_STATE) && (!access_permit_write(stp->st_access_bmap)))
                goto out;
	if ((flags & RD_STATE) && (!access_permit_read(stp->st_access_bmap)))
                goto out;
	status = nfs_ok;
out:
	return status;
}

static inline __be32
check_special_stateids(svc_fh *current_fh, stateid_t *stateid, int flags)
{
	/* Trying to call delegreturn with a special stateid? Yuch: */
	if (!(flags & (RD_STATE | WR_STATE)))
		return nfserr_bad_stateid;
	else if (ONE_STATEID(stateid) && (flags & RD_STATE))
		return nfs_ok;
	else if (nfs4_in_grace()) {
		/* Answer in remaining cases depends on existance of
		 * conflicting state; so we must wait out the grace period. */
		return nfserr_grace;
	} else if (flags & WR_STATE)
		return nfs4_share_conflict(current_fh,
				NFS4_SHARE_DENY_WRITE);
	else /* (flags & RD_STATE) && ZERO_STATEID(stateid) */
		return nfs4_share_conflict(current_fh,
				NFS4_SHARE_DENY_READ);
}

/*
 * Allow READ/WRITE during grace period on recovered state only for files
 * that are not able to provide mandatory locking.
 */
static inline int
io_during_grace_disallowed(struct inode *inode, int flags)
{
	return nfs4_in_grace() && (flags & (RD_STATE | WR_STATE))
		&& mandatory_lock(inode);
}

/*
* Checks for stateid operations
*/
__be32
nfs4_preprocess_stateid_op(struct svc_fh *current_fh, stateid_t *stateid, int flags, struct file **filpp)
{
	struct nfs4_stateid *stp = NULL;
	struct nfs4_delegation *dp = NULL;
	stateid_t *stidp;
	struct inode *ino = current_fh->fh_dentry->d_inode;
	__be32 status;

	dprintk("NFSD: preprocess_stateid_op: stateid = (%08x/%08x/%08x/%08x)\n",
		stateid->si_boot, stateid->si_stateownerid, 
		stateid->si_fileid, stateid->si_generation); 
	if (filpp)
		*filpp = NULL;

	if (io_during_grace_disallowed(ino, flags))
		return nfserr_grace;

	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid))
		return check_special_stateids(current_fh, stateid, flags);

	/* STALE STATEID */
	status = nfserr_stale_stateid;
	if (STALE_STATEID(stateid)) 
		goto out;

	/* BAD STATEID */
	status = nfserr_bad_stateid;
	if (!stateid->si_fileid) { /* delegation stateid */
		if(!(dp = find_delegation_stateid(ino, stateid))) {
			dprintk("NFSD: delegation stateid not found\n");
			goto out;
		}
		stidp = &dp->dl_stateid;
	} else { /* open or lock stateid */
		if (!(stp = find_stateid(stateid, flags))) {
			dprintk("NFSD: open or lock stateid not found\n");
			goto out;
		}
		if ((flags & CHECK_FH) && nfs4_check_fh(current_fh, stp))
			goto out;
		if (!stp->st_stateowner->so_confirmed)
			goto out;
		stidp = &stp->st_stateid;
	}
	if (stateid->si_generation > stidp->si_generation)
		goto out;

	/* OLD STATEID */
	status = nfserr_old_stateid;
	if (stateid->si_generation < stidp->si_generation)
		goto out;
	if (stp) {
		if ((status = nfs4_check_openmode(stp,flags)))
			goto out;
		renew_client(stp->st_stateowner->so_client);
		if (filpp)
			*filpp = stp->st_vfs_file;
	} else if (dp) {
		if ((status = nfs4_check_delegmode(dp, flags)))
			goto out;
		renew_client(dp->dl_client);
		if (flags & DELEG_RET)
			unhash_delegation(dp);
		if (filpp)
			*filpp = dp->dl_vfs_file;
	}
	status = nfs_ok;
out:
	return status;
}

static inline int
setlkflg (int type)
{
	return (type == NFS4_READW_LT || type == NFS4_READ_LT) ?
		RD_STATE : WR_STATE;
}

/* 
 * Checks for sequence id mutating operations. 
 */
static __be32
nfs4_preprocess_seqid_op(struct svc_fh *current_fh, u32 seqid, stateid_t *stateid, int flags, struct nfs4_stateowner **sopp, struct nfs4_stateid **stpp, struct nfsd4_lock *lock)
{
	struct nfs4_stateid *stp;
	struct nfs4_stateowner *sop;

	dprintk("NFSD: preprocess_seqid_op: seqid=%d " 
			"stateid = (%08x/%08x/%08x/%08x)\n", seqid,
		stateid->si_boot, stateid->si_stateownerid, stateid->si_fileid,
		stateid->si_generation);

	*stpp = NULL;
	*sopp = NULL;

	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid)) {
		dprintk("NFSD: preprocess_seqid_op: magic stateid!\n");
		return nfserr_bad_stateid;
	}

	if (STALE_STATEID(stateid))
		return nfserr_stale_stateid;
	/*
	* We return BAD_STATEID if filehandle doesn't match stateid, 
	* the confirmed flag is incorrecly set, or the generation 
	* number is incorrect.  
	*/
	stp = find_stateid(stateid, flags);
	if (stp == NULL) {
		/*
		 * Also, we should make sure this isn't just the result of
		 * a replayed close:
		 */
		sop = search_close_lru(stateid->si_stateownerid, flags);
		if (sop == NULL)
			return nfserr_bad_stateid;
		*sopp = sop;
		goto check_replay;
	}

	if (lock) {
		struct nfs4_stateowner *sop = stp->st_stateowner;
		clientid_t *lockclid = &lock->v.new.clientid;
		struct nfs4_client *clp = sop->so_client;
		int lkflg = 0;
		__be32 status;

		lkflg = setlkflg(lock->lk_type);

		if (lock->lk_is_new) {
			if (!sop->so_is_open_owner)
				return nfserr_bad_stateid;
			if (!same_clid(&clp->cl_clientid, lockclid))
			       return nfserr_bad_stateid;
			/* stp is the open stateid */
			status = nfs4_check_openmode(stp, lkflg);
			if (status)
				return status;
		} else {
			/* stp is the lock stateid */
			status = nfs4_check_openmode(stp->st_openstp, lkflg);
			if (status)
				return status;
               }
	}

	if ((flags & CHECK_FH) && nfs4_check_fh(current_fh, stp)) {
		dprintk("NFSD: preprocess_seqid_op: fh-stateid mismatch!\n");
		return nfserr_bad_stateid;
	}

	*stpp = stp;
	*sopp = sop = stp->st_stateowner;

	/*
	*  We now validate the seqid and stateid generation numbers.
	*  For the moment, we ignore the possibility of 
	*  generation number wraparound.
	*/
	if (seqid != sop->so_seqid)
		goto check_replay;

	if (sop->so_confirmed && flags & CONFIRM) {
		dprintk("NFSD: preprocess_seqid_op: expected"
				" unconfirmed stateowner!\n");
		return nfserr_bad_stateid;
	}
	if (!sop->so_confirmed && !(flags & CONFIRM)) {
		dprintk("NFSD: preprocess_seqid_op: stateowner not"
				" confirmed yet!\n");
		return nfserr_bad_stateid;
	}
	if (stateid->si_generation > stp->st_stateid.si_generation) {
		dprintk("NFSD: preprocess_seqid_op: future stateid?!\n");
		return nfserr_bad_stateid;
	}

	if (stateid->si_generation < stp->st_stateid.si_generation) {
		dprintk("NFSD: preprocess_seqid_op: old stateid!\n");
		return nfserr_old_stateid;
	}
	renew_client(sop->so_client);
	return nfs_ok;

check_replay:
	if (seqid == sop->so_seqid - 1) {
		dprintk("NFSD: preprocess_seqid_op: retransmission?\n");
		/* indicate replay to calling function */
		return nfserr_replay_me;
	}
	dprintk("NFSD: preprocess_seqid_op: bad seqid (expected %d, got %d)\n",
			sop->so_seqid, seqid);
	*sopp = NULL;
	return nfserr_bad_seqid;
}

__be32
nfsd4_open_confirm(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
		   struct nfsd4_open_confirm *oc)
{
	__be32 status;
	struct nfs4_stateowner *sop;
	struct nfs4_stateid *stp;

	dprintk("NFSD: nfsd4_open_confirm on file %.*s\n",
			(int)cstate->current_fh.fh_dentry->d_name.len,
			cstate->current_fh.fh_dentry->d_name.name);

	status = fh_verify(rqstp, &cstate->current_fh, S_IFREG, 0);
	if (status)
		return status;

	nfs4_lock_state();

	if ((status = nfs4_preprocess_seqid_op(&cstate->current_fh,
					oc->oc_seqid, &oc->oc_req_stateid,
					CHECK_FH | CONFIRM | OPEN_STATE,
					&oc->oc_stateowner, &stp, NULL)))
		goto out; 

	sop = oc->oc_stateowner;
	sop->so_confirmed = 1;
	update_stateid(&stp->st_stateid);
	memcpy(&oc->oc_resp_stateid, &stp->st_stateid, sizeof(stateid_t));
	dprintk("NFSD: nfsd4_open_confirm: success, seqid=%d " 
		"stateid=(%08x/%08x/%08x/%08x)\n", oc->oc_seqid,
		         stp->st_stateid.si_boot,
		         stp->st_stateid.si_stateownerid,
		         stp->st_stateid.si_fileid,
		         stp->st_stateid.si_generation);

	nfsd4_create_clid_dir(sop->so_client);
out:
	if (oc->oc_stateowner) {
		nfs4_get_stateowner(oc->oc_stateowner);
		cstate->replay_owner = oc->oc_stateowner;
	}
	nfs4_unlock_state();
	return status;
}


/*
 * unset all bits in union bitmap (bmap) that
 * do not exist in share (from successful OPEN_DOWNGRADE)
 */
static void
reset_union_bmap_access(unsigned long access, unsigned long *bmap)
{
	int i;
	for (i = 1; i < 4; i++) {
		if ((i & access) != i)
			__clear_bit(i, bmap);
	}
}

static void
reset_union_bmap_deny(unsigned long deny, unsigned long *bmap)
{
	int i;
	for (i = 0; i < 4; i++) {
		if ((i & deny) != i)
			__clear_bit(i, bmap);
	}
}

__be32
nfsd4_open_downgrade(struct svc_rqst *rqstp,
		     struct nfsd4_compound_state *cstate,
		     struct nfsd4_open_downgrade *od)
{
	__be32 status;
	struct nfs4_stateid *stp;
	unsigned int share_access;

	dprintk("NFSD: nfsd4_open_downgrade on file %.*s\n", 
			(int)cstate->current_fh.fh_dentry->d_name.len,
			cstate->current_fh.fh_dentry->d_name.name);

	if (!access_valid(od->od_share_access)
			|| !deny_valid(od->od_share_deny))
		return nfserr_inval;

	nfs4_lock_state();
	if ((status = nfs4_preprocess_seqid_op(&cstate->current_fh,
					od->od_seqid,
					&od->od_stateid, 
					CHECK_FH | OPEN_STATE, 
					&od->od_stateowner, &stp, NULL)))
		goto out; 

	status = nfserr_inval;
	if (!test_bit(od->od_share_access, &stp->st_access_bmap)) {
		dprintk("NFSD:access not a subset current bitmap: 0x%lx, input access=%08x\n",
			stp->st_access_bmap, od->od_share_access);
		goto out;
	}
	if (!test_bit(od->od_share_deny, &stp->st_deny_bmap)) {
		dprintk("NFSD:deny not a subset current bitmap: 0x%lx, input deny=%08x\n",
			stp->st_deny_bmap, od->od_share_deny);
		goto out;
	}
	set_access(&share_access, stp->st_access_bmap);
	nfs4_file_downgrade(stp->st_vfs_file,
	                    share_access & ~od->od_share_access);

	reset_union_bmap_access(od->od_share_access, &stp->st_access_bmap);
	reset_union_bmap_deny(od->od_share_deny, &stp->st_deny_bmap);

	update_stateid(&stp->st_stateid);
	memcpy(&od->od_stateid, &stp->st_stateid, sizeof(stateid_t));
	status = nfs_ok;
out:
	if (od->od_stateowner) {
		nfs4_get_stateowner(od->od_stateowner);
		cstate->replay_owner = od->od_stateowner;
	}
	nfs4_unlock_state();
	return status;
}

/*
 * nfs4_unlock_state() called after encode
 */
__be32
nfsd4_close(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	    struct nfsd4_close *close)
{
	__be32 status;
	struct nfs4_stateid *stp;

	dprintk("NFSD: nfsd4_close on file %.*s\n", 
			(int)cstate->current_fh.fh_dentry->d_name.len,
			cstate->current_fh.fh_dentry->d_name.name);

	nfs4_lock_state();
	/* check close_lru for replay */
	if ((status = nfs4_preprocess_seqid_op(&cstate->current_fh,
					close->cl_seqid,
					&close->cl_stateid, 
					CHECK_FH | OPEN_STATE | CLOSE_STATE,
					&close->cl_stateowner, &stp, NULL)))
		goto out; 
	status = nfs_ok;
	update_stateid(&stp->st_stateid);
	memcpy(&close->cl_stateid, &stp->st_stateid, sizeof(stateid_t));

	/* release_stateid() calls nfsd_close() if needed */
	release_stateid(stp, OPEN_STATE);

	/* place unused nfs4_stateowners on so_close_lru list to be
	 * released by the laundromat service after the lease period
	 * to enable us to handle CLOSE replay
	 */
	if (list_empty(&close->cl_stateowner->so_stateids))
		move_to_close_lru(close->cl_stateowner);
out:
	if (close->cl_stateowner) {
		nfs4_get_stateowner(close->cl_stateowner);
		cstate->replay_owner = close->cl_stateowner;
	}
	nfs4_unlock_state();
	return status;
}

__be32
nfsd4_delegreturn(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
		  struct nfsd4_delegreturn *dr)
{
	__be32 status;

	if ((status = fh_verify(rqstp, &cstate->current_fh, S_IFREG, 0)))
		goto out;

	nfs4_lock_state();
	status = nfs4_preprocess_stateid_op(&cstate->current_fh,
					    &dr->dr_stateid, DELEG_RET, NULL);
	nfs4_unlock_state();
out:
	return status;
}


/* 
 * Lock owner state (byte-range locks)
 */
#define LOFF_OVERFLOW(start, len)      ((u64)(len) > ~(u64)(start))
#define LOCK_HASH_BITS              8
#define LOCK_HASH_SIZE             (1 << LOCK_HASH_BITS)
#define LOCK_HASH_MASK             (LOCK_HASH_SIZE - 1)

#define lockownerid_hashval(id) \
        ((id) & LOCK_HASH_MASK)

static inline unsigned int
lock_ownerstr_hashval(struct inode *inode, u32 cl_id,
		struct xdr_netobj *ownername)
{
	return (file_hashval(inode) + cl_id
			+ opaque_hashval(ownername->data, ownername->len))
		& LOCK_HASH_MASK;
}

static struct list_head lock_ownerid_hashtbl[LOCK_HASH_SIZE];
static struct lis