nfs4proc.c

linux 内核源代码

static __be32
nfsd4_readlink(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	       struct nfsd4_readlink *readlink)
{
	readlink->rl_rqstp = rqstp;
	readlink->rl_fhp = &cstate->current_fh;
	return nfs_ok;
}

static __be32
nfsd4_remove(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	     struct nfsd4_remove *remove)
{
	__be32 status;

	if (nfs4_in_grace())
		return nfserr_grace;
	status = nfsd_unlink(rqstp, &cstate->current_fh, 0,
			     remove->rm_name, remove->rm_namelen);
	if (status == nfserr_symlink)
		return nfserr_notdir;
	if (!status) {
		fh_unlock(&cstate->current_fh);
		set_change_info(&remove->rm_cinfo, &cstate->current_fh);
	}
	return status;
}

static __be32
nfsd4_rename(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	     struct nfsd4_rename *rename)
{
	__be32 status = nfserr_nofilehandle;

	if (!cstate->save_fh.fh_dentry)
		return status;
	if (nfs4_in_grace() && !(cstate->save_fh.fh_export->ex_flags
					& NFSEXP_NOSUBTREECHECK))
		return nfserr_grace;
	status = nfsd_rename(rqstp, &cstate->save_fh, rename->rn_sname,
			     rename->rn_snamelen, &cstate->current_fh,
			     rename->rn_tname, rename->rn_tnamelen);

	/* the underlying filesystem returns different error's than required
	 * by NFSv4. both save_fh and current_fh have been verified.. */
	if (status == nfserr_isdir)
		status = nfserr_exist;
	else if ((status == nfserr_notdir) &&
                  (S_ISDIR(cstate->save_fh.fh_dentry->d_inode->i_mode) &&
                   S_ISDIR(cstate->current_fh.fh_dentry->d_inode->i_mode)))
		status = nfserr_exist;
	else if (status == nfserr_symlink)
		status = nfserr_notdir;

	if (!status) {
		set_change_info(&rename->rn_sinfo, &cstate->current_fh);
		set_change_info(&rename->rn_tinfo, &cstate->save_fh);
	}
	return status;
}

static __be32
nfsd4_secinfo(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	      struct nfsd4_secinfo *secinfo)
{
	struct svc_fh resfh;
	struct svc_export *exp;
	struct dentry *dentry;
	__be32 err;

	fh_init(&resfh, NFS4_FHSIZE);
	err = nfsd_lookup_dentry(rqstp, &cstate->current_fh,
				    secinfo->si_name, secinfo->si_namelen,
				    &exp, &dentry);
	if (err)
		return err;
	if (dentry->d_inode == NULL) {
		exp_put(exp);
		err = nfserr_noent;
	} else
		secinfo->si_exp = exp;
	dput(dentry);
	return err;
}

static __be32
nfsd4_setattr(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	      struct nfsd4_setattr *setattr)
{
	__be32 status = nfs_ok;

	if (setattr->sa_iattr.ia_valid & ATTR_SIZE) {
		nfs4_lock_state();
		status = nfs4_preprocess_stateid_op(&cstate->current_fh,
			&setattr->sa_stateid, CHECK_FH | WR_STATE, NULL);
		nfs4_unlock_state();
		if (status) {
			dprintk("NFSD: nfsd4_setattr: couldn't process stateid!\n");
			return status;
		}
	}
	status = nfs_ok;
	if (setattr->sa_acl != NULL)
		status = nfsd4_set_nfs4_acl(rqstp, &cstate->current_fh,
					    setattr->sa_acl);
	if (status)
		return status;
	status = nfsd_setattr(rqstp, &cstate->current_fh, &setattr->sa_iattr,
				0, (time_t)0);
	return status;
}

static __be32
nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	    struct nfsd4_write *write)
{
	stateid_t *stateid = &write->wr_stateid;
	struct file *filp = NULL;
	u32 *p;
	__be32 status = nfs_ok;

	/* no need to check permission - this will be done in nfsd_write() */

	if (write->wr_offset >= OFFSET_MAX)
		return nfserr_inval;

	nfs4_lock_state();
	status = nfs4_preprocess_stateid_op(&cstate->current_fh, stateid,
					CHECK_FH | WR_STATE, &filp);
	if (filp)
		get_file(filp);
	nfs4_unlock_state();

	if (status) {
		dprintk("NFSD: nfsd4_write: couldn't process stateid!\n");
		return status;
	}

	write->wr_bytes_written = write->wr_buflen;
	write->wr_how_written = write->wr_stable_how;
	p = (u32 *)write->wr_verifier.data;
	*p++ = nfssvc_boot.tv_sec;
	*p++ = nfssvc_boot.tv_usec;

	status =  nfsd_write(rqstp, &cstate->current_fh, filp,
			     write->wr_offset, rqstp->rq_vec, write->wr_vlen,
			     write->wr_buflen, &write->wr_how_written);
	if (filp)
		fput(filp);

	if (status == nfserr_symlink)
		status = nfserr_inval;
	return status;
}

/* This routine never returns NFS_OK!  If there are no other errors, it
 * will return NFSERR_SAME or NFSERR_NOT_SAME depending on whether the
 * attributes matched.  VERIFY is implemented by mapping NFSERR_SAME
 * to NFS_OK after the call; NVERIFY by mapping NFSERR_NOT_SAME to NFS_OK.
 */
static __be32
_nfsd4_verify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	     struct nfsd4_verify *verify)
{
	__be32 *buf, *p;
	int count;
	__be32 status;

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

	if ((verify->ve_bmval[0] & ~NFSD_SUPPORTED_ATTRS_WORD0)
	    || (verify->ve_bmval[1] & ~NFSD_SUPPORTED_ATTRS_WORD1))
		return nfserr_attrnotsupp;
	if ((verify->ve_bmval[0] & FATTR4_WORD0_RDATTR_ERROR)
	    || (verify->ve_bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1))
		return nfserr_inval;
	if (verify->ve_attrlen & 3)
		return nfserr_inval;

	/* count in words:
	 *   bitmap_len(1) + bitmap(2) + attr_len(1) = 4
	 */
	count = 4 + (verify->ve_attrlen >> 2);
	buf = kmalloc(count << 2, GFP_KERNEL);
	if (!buf)
		return nfserr_resource;

	status = nfsd4_encode_fattr(&cstate->current_fh,
				    cstate->current_fh.fh_export,
				    cstate->current_fh.fh_dentry, buf,
				    &count, verify->ve_bmval,
				    rqstp);

	/* this means that nfsd4_encode_fattr() ran out of space */
	if (status == nfserr_resource && count == 0)
		status = nfserr_not_same;
	if (status)
		goto out_kfree;

	p = buf + 3;
	status = nfserr_not_same;
	if (ntohl(*p++) != verify->ve_attrlen)
		goto out_kfree;
	if (!memcmp(p, verify->ve_attrval, verify->ve_attrlen))
		status = nfserr_same;

out_kfree:
	kfree(buf);
	return status;
}

static __be32
nfsd4_nverify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	      struct nfsd4_verify *verify)
{
	__be32 status;

	status = _nfsd4_verify(rqstp, cstate, verify);
	return status == nfserr_not_same ? nfs_ok : status;
}

static __be32
nfsd4_verify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	     struct nfsd4_verify *verify)
{
	__be32 status;

	status = _nfsd4_verify(rqstp, cstate, verify);
	return status == nfserr_same ? nfs_ok : status;
}

/*
 * NULL call.
 */
static __be32
nfsd4_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
{
	return nfs_ok;
}

static inline void nfsd4_increment_op_stats(u32 opnum)
{
	if (opnum >= FIRST_NFS4_OP && opnum <= LAST_NFS4_OP)
		nfsdstats.nfs4_opcount[opnum]++;
}

static void cstate_free(struct nfsd4_compound_state *cstate)
{
	if (cstate == NULL)
		return;
	fh_put(&cstate->current_fh);
	fh_put(&cstate->save_fh);
	BUG_ON(cstate->replay_owner);
	kfree(cstate);
}

static struct nfsd4_compound_state *cstate_alloc(void)
{
	struct nfsd4_compound_state *cstate;

	cstate = kmalloc(sizeof(struct nfsd4_compound_state), GFP_KERNEL);
	if (cstate == NULL)
		return NULL;
	fh_init(&cstate->current_fh, NFS4_FHSIZE);
	fh_init(&cstate->save_fh, NFS4_FHSIZE);
	cstate->replay_owner = NULL;
	return cstate;
}

typedef __be32(*nfsd4op_func)(struct svc_rqst *, struct nfsd4_compound_state *,
			      void *);

struct nfsd4_operation {
	nfsd4op_func op_func;
	u32 op_flags;
/* Most ops require a valid current filehandle; a few don't: */
#define ALLOWED_WITHOUT_FH 1
/* GETATTR and ops not listed as returning NFS4ERR_MOVED: */
#define ALLOWED_ON_ABSENT_FS 2
};

static struct nfsd4_operation nfsd4_ops[];

/*
 * COMPOUND call.
 */
static __be32
nfsd4_proc_compound(struct svc_rqst *rqstp,
		    struct nfsd4_compoundargs *args,
		    struct nfsd4_compoundres *resp)
{
	struct nfsd4_op	*op;
	struct nfsd4_operation *opdesc;
	struct nfsd4_compound_state *cstate = NULL;
	int		slack_bytes;
	__be32		status;

	status = nfserr_resource;
	cstate = cstate_alloc();
	if (cstate == NULL)
		goto out;

	resp->xbuf = &rqstp->rq_res;
	resp->p = rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len;
	resp->tagp = resp->p;
	/* reserve space for: taglen, tag, and opcnt */
	resp->p += 2 + XDR_QUADLEN(args->taglen);
	resp->end = rqstp->rq_res.head[0].iov_base + PAGE_SIZE;
	resp->taglen = args->taglen;
	resp->tag = args->tag;
	resp->opcnt = 0;
	resp->rqstp = rqstp;

	/*
	 * According to RFC3010, this takes precedence over all other errors.
	 */
	status = nfserr_minor_vers_mismatch;
	if (args->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
		goto out;

	status = nfs_ok;
	while (!status && resp->opcnt < args->opcnt) {
		op = &args->ops[resp->opcnt++];

		dprintk("nfsv4 compound op #%d: %d\n", resp->opcnt, op->opnum);

		/*
		 * The XDR decode routines may have pre-set op->status;
		 * for example, if there is a miscellaneous XDR error
		 * it will be set to nfserr_bad_xdr.
		 */
		if (op->status)
			goto encode_op;

		/* We must be able to encode a successful response to
		 * this operation, with enough room left over to encode a
		 * failed response to the next operation.  If we don't
		 * have enough room, fail with ERR_RESOURCE.
		 */
		slack_bytes = (char *)resp->end - (char *)resp->p;
		if (slack_bytes < COMPOUND_SLACK_SPACE
				+ COMPOUND_ERR_SLACK_SPACE) {
			BUG_ON(slack_bytes < COMPOUND_ERR_SLACK_SPACE);
			op->status = nfserr_resource;
			goto encode_op;
		}

		opdesc = &nfsd4_ops[op->opnum];

		if (!cstate->current_fh.fh_dentry) {
			if (!(opdesc->op_flags & ALLOWED_WITHOUT_FH)) {
				op->status = nfserr_nofilehandle;
				goto encode_op;
			}
		} else if (cstate->current_fh.fh_export->ex_fslocs.migrated &&
			  !(opdesc->op_flags & ALLOWED_ON_ABSENT_FS)) {
			op->status = nfserr_moved;
			goto encode_op;
		}

		if (opdesc->op_func)
			op->status = opdesc->op_func(rqstp, cstate, &op->u);
		else
			BUG_ON(op->status == nfs_ok);

encode_op:
		if (op->status == nfserr_replay_me) {
			op->replay = &cstate->replay_owner->so_replay;
			nfsd4_encode_replay(resp, op);
			status = op->status = op->replay->rp_status;
		} else {
			nfsd4_encode_operation(resp, op);
			status = op->status;
		}
		if (cstate->replay_owner) {
			nfs4_put_stateowner(cstate->replay_owner);
			cstate->replay_owner = NULL;
		}
		/* XXX Ugh, we need to get rid of this kind of special case: */
		if (op->opnum == OP_READ && op->u.read.rd_filp)
			fput(op->u.read.rd_filp);

		nfsd4_increment_op_stats(op->opnum);
	}

out:
	nfsd4_release_compoundargs(args);
	cstate_free(cstate);
	return status;
}

static struct nfsd4_operation nfsd4_ops[OP_RELEASE_LOCKOWNER+1] = {
	[OP_ACCESS] = {
		.op_func = (nfsd4op_func)nfsd4_access,
	},
	[OP_CLOSE] = {
		.op_func = (nfsd4op_func)nfsd4_close,
	},
	[OP_COMMIT] = {
		.op_func = (nfsd4op_func)nfsd4_commit,
	},
	[OP_CREATE] = {
		.op_func = (nfsd4op_func)nfsd4_create,
	},
	[OP_DELEGRETURN] = {
		.op_func = (nfsd4op_func)nfsd4_delegreturn,
	},
	[OP_GETATTR] = {
		.op_func = (nfsd4op_func)nfsd4_getattr,
		.op_flags = ALLOWED_ON_ABSENT_FS,
	},
	[OP_GETFH] = {
		.op_func = (nfsd4op_func)nfsd4_getfh,
	},
	[OP_LINK] = {
		.op_func = (nfsd4op_func)nfsd4_link,
	},
	[OP_LOCK] = {
		.op_func = (nfsd4op_func)nfsd4_lock,
	},
	[OP_LOCKT] = {
		.op_func = (nfsd4op_func)nfsd4_lockt,
	},
	[OP_LOCKU] = {
		.op_func = (nfsd4op_func)nfsd4_locku,
	},
	[OP_LOOKUP] = {
		.op_func = (nfsd4op_func)nfsd4_lookup,
	},
	[OP_LOOKUPP] = {
		.op_func = (nfsd4op_func)nfsd4_lookupp,
	},
	[OP_NVERIFY] = {
		.op_func = (nfsd4op_func)nfsd4_nverify,
	},
	[OP_OPEN] = {
		.op_func = (nfsd4op_func)nfsd4_open,
	},
	[OP_OPEN_CONFIRM] = {
		.op_func = (nfsd4op_func)nfsd4_open_confirm,
	},
	[OP_OPEN_DOWNGRADE] = {
		.op_func = (nfsd4op_func)nfsd4_open_downgrade,
	},
	[OP_PUTFH] = {
		.op_func = (nfsd4op_func)nfsd4_putfh,
		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
	},
	[OP_PUTPUBFH] = {
		/* unsupported; just for future reference: */
		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
	},
	[OP_PUTROOTFH] = {
		.op_func = (nfsd4op_func)nfsd4_putrootfh,
		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
	},
	[OP_READ] = {
		.op_func = (nfsd4op_func)nfsd4_read,
	},
	[OP_READDIR] = {
		.op_func = (nfsd4op_func)nfsd4_readdir,
	},
	[OP_READLINK] = {
		.op_func = (nfsd4op_func)nfsd4_readlink,
	},
	[OP_REMOVE] = {
		.op_func = (nfsd4op_func)nfsd4_remove,
	},
	[OP_RENAME] = {
		.op_func = (nfsd4op_func)nfsd4_rename,
	},
	[OP_RENEW] = {
		.op_func = (nfsd4op_func)nfsd4_renew,
		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
	},
	[OP_RESTOREFH] = {
		.op_func = (nfsd4op_func)nfsd4_restorefh,
		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
	},
	[OP_SAVEFH] = {
		.op_func = (nfsd4op_func)nfsd4_savefh,
	},
	[OP_SECINFO] = {
		.op_func = (nfsd4op_func)nfsd4_secinfo,
	},
	[OP_SETATTR] = {
		.op_func = (nfsd4op_func)nfsd4_setattr,
	},
	[OP_SETCLIENTID] = {
		.op_func = (nfsd4op_func)nfsd4_setclientid,
		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
	},
	[OP_SETCLIENTID_CONFIRM] = {
		.op_func = (nfsd4op_func)nfsd4_setclientid_confirm,
		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
	},
	[OP_VERIFY] = {
		.op_func = (nfsd4op_func)nfsd4_verify,
	},
	[OP_WRITE] = {
		.op_func = (nfsd4op_func)nfsd4_write,
	},
	[OP_RELEASE_LOCKOWNER] = {
		.op_func = (nfsd4op_func)nfsd4_release_lockowner,
		.op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
	},
};

#define nfs4svc_decode_voidargs		NULL
#define nfs4svc_release_void		NULL
#define nfsd4_voidres			nfsd4_voidargs
#define nfs4svc_release_compound	NULL
struct nfsd4_voidargs { int dummy; };

#define PROC(name, argt, rest, relt, cache, respsize)	\
 { (svc_procfunc) nfsd4_proc_##name,		\
   (kxdrproc_t) nfs4svc_decode_##argt##args,	\
   (kxdrproc_t) nfs4svc_encode_##rest##res,	\
   (kxdrproc_t) nfs4svc_release_##relt,		\
   sizeof(struct nfsd4_##argt##args),		\
   sizeof(struct nfsd4_##rest##res),		\
   0,						\
   cache,					\
   respsize,					\
 }

/*
 * TODO: At the present time, the NFSv4 server does not do XID caching
 * of requests.  Implementing XID caching would not be a serious problem,
 * although it would require a mild change in interfaces since one
 * doesn't know whether an NFSv4 request is idempotent until after the
 * XDR decode.  However, XID caching totally confuses pynfs (Peter
 * Astrand's regression testsuite for NFSv4 servers), which reuses
 * XID's liberally, so I've left it unimplemented until pynfs generates
 * better XID's.
 */
static struct svc_procedure		nfsd_procedures4[2] = {
  PROC(null,	 void,		void,		void,	  RC_NOCACHE, 1),
  PROC(compound, compound,	compound,	compound, RC_NOCACHE, NFSD_BUFSIZE/4)
};

struct svc_version	nfsd_version4 = {
		.vs_vers	= 4,
		.vs_nproc	= 2,
		.vs_proc	= nfsd_procedures4,
		.vs_dispatch	= nfsd_dispatch,
		.vs_xdrsize	= NFS4_SVC_XDRSIZE,
};

/*
 * Local variables:
 *  c-basic-offset: 8
 * End:
 */