/* * linux/fs/lockd/svcshare.c * * Management of DOS shares. * * Copyright (C) 1996 Olaf Kirch <okir@monad.swb.de> */#include <linux/time.h>#include <linux/unistd.h>#include <linux/string.h>#include <linux/slab.h>#include <linux/sunrpc/clnt.h>#include <linux/sunrpc/svc.h>#include <linux/lockd/lockd.h>#include <linux/lockd/share.h>static inline intnlm_cmp_owner(struct nlm_share *share, struct xdr_netobj *oh){	return share->s_owner.len == oh->len	    && !memcmp(share->s_owner.data, oh->data, oh->len);}__be32nlmsvc_share_file(struct nlm_host *host, struct nlm_file *file,			struct nlm_args *argp){	struct nlm_share	*share;	struct xdr_netobj	*oh = &argp->lock.oh;	u8			*ohdata;	for (share = file->f_shares; share; share = share->s_next) {		if (share->s_host == host && nlm_cmp_owner(share, oh))			goto update;		if ((argp->fsm_access & share->s_mode)		 || (argp->fsm_mode   & share->s_access ))			return nlm_lck_denied;	}	share = kmalloc(sizeof(*share) + oh->len,						GFP_KERNEL);	if (share == NULL)		return nlm_lck_denied_nolocks;	/* Copy owner handle */	ohdata = (u8 *) (share + 1);	memcpy(ohdata, oh->data, oh->len);	share->s_file	    = file;	share->s_host       = host;	share->s_owner.data = ohdata;	share->s_owner.len  = oh->len;	share->s_next       = file->f_shares;	file->f_shares      = share;update:	share->s_access = argp->fsm_access;	share->s_mode   = argp->fsm_mode;	return nlm_granted;}/* * Delete a share. */__be32nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file,			struct nlm_args *argp){	struct nlm_share	*share, **shpp;	struct xdr_netobj	*oh = &argp->lock.oh;	for (shpp = &file->f_shares; (share = *shpp) != NULL;					shpp = &share->s_next) {		if (share->s_host == host && nlm_cmp_owner(share, oh)) {			*shpp = share->s_next;			kfree(share);			return nlm_granted;		}	}	/* X/Open spec says return success even if there was no	 * corresponding share. */	return nlm_granted;}/* * Traverse all shares for a given file, and delete * those owned by the given (type of) host */void nlmsvc_traverse_shares(struct nlm_host *host, struct nlm_file *file,		nlm_host_match_fn_t match){	struct nlm_share	*share, **shpp;	shpp = &file->f_shares;	while ((share = *shpp) !=  NULL) {		if (match(share->s_host, host)) {			*shpp = share->s_next;			kfree(share);			continue;		}		shpp = &share->s_next;	}}