nfsproc.c

linux 内核源代码

		/* we've used the SIZE information, so discard it */
		attr->ia_valid &= ~ATTR_SIZE;

		/* Make sure the type and device matches */
		nfserr = nfserr_exist;
		if (inode && type != (inode->i_mode & S_IFMT))
			goto out_unlock;
	}

	nfserr = 0;
	if (!inode) {
		/* File doesn't exist. Create it and set attrs */
		nfserr = nfsd_create(rqstp, dirfhp, argp->name, argp->len,
					attr, type, rdev, newfhp);
	} else if (type == S_IFREG) {
		dprintk("nfsd:   existing %s, valid=%x, size=%ld\n",
			argp->name, attr->ia_valid, (long) attr->ia_size);
		/* File already exists. We ignore all attributes except
		 * size, so that creat() behaves exactly like
		 * open(..., O_CREAT|O_TRUNC|O_WRONLY).
		 */
		attr->ia_valid &= ATTR_SIZE;
		if (attr->ia_valid)
			nfserr = nfsd_setattr(rqstp, newfhp, attr, 0, (time_t)0);
	}

out_unlock:
	/* We don't really need to unlock, as fh_put does it. */
	fh_unlock(dirfhp);

done:
	fh_put(dirfhp);
	return nfsd_return_dirop(nfserr, resp);
}

static __be32
nfsd_proc_remove(struct svc_rqst *rqstp, struct nfsd_diropargs *argp,
					 void		       *resp)
{
	__be32	nfserr;

	dprintk("nfsd: REMOVE   %s %.*s\n", SVCFH_fmt(&argp->fh),
		argp->len, argp->name);

	/* Unlink. -SIFDIR means file must not be a directory */
	nfserr = nfsd_unlink(rqstp, &argp->fh, -S_IFDIR, argp->name, argp->len);
	fh_put(&argp->fh);
	return nfserr;
}

static __be32
nfsd_proc_rename(struct svc_rqst *rqstp, struct nfsd_renameargs *argp,
				  	 void		        *resp)
{
	__be32	nfserr;

	dprintk("nfsd: RENAME   %s %.*s -> \n",
		SVCFH_fmt(&argp->ffh), argp->flen, argp->fname);
	dprintk("nfsd:        ->  %s %.*s\n",
		SVCFH_fmt(&argp->tfh), argp->tlen, argp->tname);

	nfserr = nfsd_rename(rqstp, &argp->ffh, argp->fname, argp->flen,
				    &argp->tfh, argp->tname, argp->tlen);
	fh_put(&argp->ffh);
	fh_put(&argp->tfh);
	return nfserr;
}

static __be32
nfsd_proc_link(struct svc_rqst *rqstp, struct nfsd_linkargs *argp,
				void			    *resp)
{
	__be32	nfserr;

	dprintk("nfsd: LINK     %s ->\n",
		SVCFH_fmt(&argp->ffh));
	dprintk("nfsd:    %s %.*s\n",
		SVCFH_fmt(&argp->tfh),
		argp->tlen,
		argp->tname);

	nfserr = nfsd_link(rqstp, &argp->tfh, argp->tname, argp->tlen,
				  &argp->ffh);
	fh_put(&argp->ffh);
	fh_put(&argp->tfh);
	return nfserr;
}

static __be32
nfsd_proc_symlink(struct svc_rqst *rqstp, struct nfsd_symlinkargs *argp,
				          void			  *resp)
{
	struct svc_fh	newfh;
	__be32		nfserr;

	dprintk("nfsd: SYMLINK  %s %.*s -> %.*s\n",
		SVCFH_fmt(&argp->ffh), argp->flen, argp->fname,
		argp->tlen, argp->tname);

	fh_init(&newfh, NFS_FHSIZE);
	/*
	 * Create the link, look up new file and set attrs.
	 */
	nfserr = nfsd_symlink(rqstp, &argp->ffh, argp->fname, argp->flen,
						 argp->tname, argp->tlen,
				 		 &newfh, &argp->attrs);


	fh_put(&argp->ffh);
	fh_put(&newfh);
	return nfserr;
}

/*
 * Make directory. This operation is not idempotent.
 * N.B. After this call resp->fh needs an fh_put
 */
static __be32
nfsd_proc_mkdir(struct svc_rqst *rqstp, struct nfsd_createargs *argp,
					struct nfsd_diropres   *resp)
{
	__be32	nfserr;

	dprintk("nfsd: MKDIR    %s %.*s\n", SVCFH_fmt(&argp->fh), argp->len, argp->name);

	if (resp->fh.fh_dentry) {
		printk(KERN_WARNING
			"nfsd_proc_mkdir: response already verified??\n");
	}

	argp->attrs.ia_valid &= ~ATTR_SIZE;
	fh_init(&resp->fh, NFS_FHSIZE);
	nfserr = nfsd_create(rqstp, &argp->fh, argp->name, argp->len,
				    &argp->attrs, S_IFDIR, 0, &resp->fh);
	fh_put(&argp->fh);
	return nfsd_return_dirop(nfserr, resp);
}

/*
 * Remove a directory
 */
static __be32
nfsd_proc_rmdir(struct svc_rqst *rqstp, struct nfsd_diropargs *argp,
				 	void		      *resp)
{
	__be32	nfserr;

	dprintk("nfsd: RMDIR    %s %.*s\n", SVCFH_fmt(&argp->fh), argp->len, argp->name);

	nfserr = nfsd_unlink(rqstp, &argp->fh, S_IFDIR, argp->name, argp->len);
	fh_put(&argp->fh);
	return nfserr;
}

/*
 * Read a portion of a directory.
 */
static __be32
nfsd_proc_readdir(struct svc_rqst *rqstp, struct nfsd_readdirargs *argp,
					  struct nfsd_readdirres  *resp)
{
	int		count;
	__be32		nfserr;
	loff_t		offset;

	dprintk("nfsd: READDIR  %s %d bytes at %d\n",
		SVCFH_fmt(&argp->fh),		
		argp->count, argp->cookie);

	/* Shrink to the client read size */
	count = (argp->count >> 2) - 2;

	/* Make sure we've room for the NULL ptr & eof flag */
	count -= 2;
	if (count < 0)
		count = 0;

	resp->buffer = argp->buffer;
	resp->offset = NULL;
	resp->buflen = count;
	resp->common.err = nfs_ok;
	/* Read directory and encode entries on the fly */
	offset = argp->cookie;
	nfserr = nfsd_readdir(rqstp, &argp->fh, &offset, 
			      &resp->common, nfssvc_encode_entry);

	resp->count = resp->buffer - argp->buffer;
	if (resp->offset)
		*resp->offset = htonl(offset);

	fh_put(&argp->fh);
	return nfserr;
}

/*
 * Get file system info
 */
static __be32
nfsd_proc_statfs(struct svc_rqst * rqstp, struct nfsd_fhandle   *argp,
					  struct nfsd_statfsres *resp)
{
	__be32	nfserr;

	dprintk("nfsd: STATFS   %s\n", SVCFH_fmt(&argp->fh));

	nfserr = nfsd_statfs(rqstp, &argp->fh, &resp->stats);
	fh_put(&argp->fh);
	return nfserr;
}

/*
 * NFSv2 Server procedures.
 * Only the results of non-idempotent operations are cached.
 */
#define nfsd_proc_none		NULL
#define nfssvc_release_none	NULL
struct nfsd_void { int dummy; };

#define PROC(name, argt, rest, relt, cache, respsize)	\
 { (svc_procfunc) nfsd_proc_##name,		\
   (kxdrproc_t) nfssvc_decode_##argt,		\
   (kxdrproc_t) nfssvc_encode_##rest,		\
   (kxdrproc_t) nfssvc_release_##relt,		\
   sizeof(struct nfsd_##argt),			\
   sizeof(struct nfsd_##rest),			\
   0,						\
   cache,					\
   respsize,				       	\
 }

#define ST 1		/* status */
#define FH 8		/* filehandle */
#define	AT 18		/* attributes */

static struct svc_procedure		nfsd_procedures2[18] = {
  PROC(null,	 void,		void,		none,		RC_NOCACHE, ST),
  PROC(getattr,	 fhandle,	attrstat,	fhandle,	RC_NOCACHE, ST+AT),
  PROC(setattr,  sattrargs,	attrstat,	fhandle,	RC_REPLBUFF, ST+AT),
  PROC(none,	 void,		void,		none,		RC_NOCACHE, ST),
  PROC(lookup,	 diropargs,	diropres,	fhandle,	RC_NOCACHE, ST+FH+AT),
  PROC(readlink, readlinkargs,	readlinkres,	none,		RC_NOCACHE, ST+1+NFS_MAXPATHLEN/4),
  PROC(read,	 readargs,	readres,	fhandle,	RC_NOCACHE, ST+AT+1+NFSSVC_MAXBLKSIZE_V2/4),
  PROC(none,	 void,		void,		none,		RC_NOCACHE, ST),
  PROC(write,	 writeargs,	attrstat,	fhandle,	RC_REPLBUFF, ST+AT),
  PROC(create,	 createargs,	diropres,	fhandle,	RC_REPLBUFF, ST+FH+AT),
  PROC(remove,	 diropargs,	void,		none,		RC_REPLSTAT, ST),
  PROC(rename,	 renameargs,	void,		none,		RC_REPLSTAT, ST),
  PROC(link,	 linkargs,	void,		none,		RC_REPLSTAT, ST),
  PROC(symlink,	 symlinkargs,	void,		none,		RC_REPLSTAT, ST),
  PROC(mkdir,	 createargs,	diropres,	fhandle,	RC_REPLBUFF, ST+FH+AT),
  PROC(rmdir,	 diropargs,	void,		none,		RC_REPLSTAT, ST),
  PROC(readdir,	 readdirargs,	readdirres,	none,		RC_NOCACHE, 0),
  PROC(statfs,	 fhandle,	statfsres,	none,		RC_NOCACHE, ST+5),
};


struct svc_version	nfsd_version2 = {
		.vs_vers	= 2,
		.vs_nproc	= 18,
		.vs_proc	= nfsd_procedures2,
		.vs_dispatch	= nfsd_dispatch,
		.vs_xdrsize	= NFS2_SVC_XDRSIZE,
};

/*
 * Map errnos to NFS errnos.
 */
__be32
nfserrno (int errno)
{
	static struct {
		__be32	nfserr;
		int	syserr;
	} nfs_errtbl[] = {
		{ nfs_ok, 0 },
		{ nfserr_perm, -EPERM },
		{ nfserr_noent, -ENOENT },
		{ nfserr_io, -EIO },
		{ nfserr_nxio, -ENXIO },
		{ nfserr_acces, -EACCES },
		{ nfserr_exist, -EEXIST },
		{ nfserr_xdev, -EXDEV },
		{ nfserr_mlink, -EMLINK },
		{ nfserr_nodev, -ENODEV },
		{ nfserr_notdir, -ENOTDIR },
		{ nfserr_isdir, -EISDIR },
		{ nfserr_inval, -EINVAL },
		{ nfserr_fbig, -EFBIG },
		{ nfserr_nospc, -ENOSPC },
		{ nfserr_rofs, -EROFS },
		{ nfserr_mlink, -EMLINK },
		{ nfserr_nametoolong, -ENAMETOOLONG },
		{ nfserr_notempty, -ENOTEMPTY },
#ifdef EDQUOT
		{ nfserr_dquot, -EDQUOT },
#endif
		{ nfserr_stale, -ESTALE },
		{ nfserr_jukebox, -ETIMEDOUT },
		{ nfserr_dropit, -EAGAIN },
		{ nfserr_dropit, -ENOMEM },
		{ nfserr_badname, -ESRCH },
		{ nfserr_io, -ETXTBSY },
		{ nfserr_notsupp, -EOPNOTSUPP },
	};
	int	i;

	for (i = 0; i < ARRAY_SIZE(nfs_errtbl); i++) {
		if (nfs_errtbl[i].syserr == errno)
			return nfs_errtbl[i].nfserr;
	}
	printk (KERN_INFO "nfsd: non-standard errno: %d\n", errno);
	return nfserr_io;
}