Change the name to reflect what we're really doing: testing two stateids for whether or not they match according the the rules in RFC3530 and RFC5661. Move the code from callback_proc.c to nfs4proc.c Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
		
			
				
	
	
		
			716 lines
		
	
	
	
		
			18 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			716 lines
		
	
	
	
		
			18 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * linux/fs/nfs/delegation.c
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 *
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 * Copyright (C) 2004 Trond Myklebust
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 *
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 * NFS file delegation management
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 *
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 */
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#include <linux/completion.h>
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#include <linux/kthread.h>
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/nfs4.h>
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#include <linux/nfs_fs.h>
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#include <linux/nfs_xdr.h>
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#include "nfs4_fs.h"
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#include "delegation.h"
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#include "internal.h"
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static void nfs_free_delegation(struct nfs_delegation *delegation)
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{
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	if (delegation->cred) {
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		put_rpccred(delegation->cred);
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		delegation->cred = NULL;
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	}
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	kfree_rcu(delegation, rcu);
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}
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/**
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 * nfs_mark_delegation_referenced - set delegation's REFERENCED flag
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 * @delegation: delegation to process
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 *
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 */
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void nfs_mark_delegation_referenced(struct nfs_delegation *delegation)
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{
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	set_bit(NFS_DELEGATION_REFERENCED, &delegation->flags);
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}
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/**
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 * nfs_have_delegation - check if inode has a delegation
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 * @inode: inode to check
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 * @flags: delegation types to check for
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 *
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 * Returns one if inode has the indicated delegation, otherwise zero.
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 */
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int nfs_have_delegation(struct inode *inode, fmode_t flags)
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{
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	struct nfs_delegation *delegation;
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	int ret = 0;
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	flags &= FMODE_READ|FMODE_WRITE;
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	rcu_read_lock();
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	delegation = rcu_dereference(NFS_I(inode)->delegation);
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	if (delegation != NULL && (delegation->type & flags) == flags) {
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		nfs_mark_delegation_referenced(delegation);
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		ret = 1;
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	}
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	rcu_read_unlock();
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	return ret;
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}
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static int nfs_delegation_claim_locks(struct nfs_open_context *ctx, struct nfs4_state *state)
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{
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	struct inode *inode = state->inode;
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	struct file_lock *fl;
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	int status = 0;
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	if (inode->i_flock == NULL)
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		goto out;
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	/* Protect inode->i_flock using the file locks lock */
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	lock_flocks();
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	for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
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		if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
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			continue;
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		if (nfs_file_open_context(fl->fl_file) != ctx)
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			continue;
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		unlock_flocks();
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		status = nfs4_lock_delegation_recall(state, fl);
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		if (status < 0)
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			goto out;
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		lock_flocks();
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	}
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	unlock_flocks();
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out:
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	return status;
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}
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static int nfs_delegation_claim_opens(struct inode *inode, const nfs4_stateid *stateid)
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{
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	struct nfs_inode *nfsi = NFS_I(inode);
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	struct nfs_open_context *ctx;
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	struct nfs4_state *state;
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	int err;
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again:
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	spin_lock(&inode->i_lock);
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	list_for_each_entry(ctx, &nfsi->open_files, list) {
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		state = ctx->state;
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		if (state == NULL)
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			continue;
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		if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
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			continue;
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		if (memcmp(state->stateid.data, stateid->data, sizeof(state->stateid.data)) != 0)
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			continue;
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		get_nfs_open_context(ctx);
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		spin_unlock(&inode->i_lock);
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		err = nfs4_open_delegation_recall(ctx, state, stateid);
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		if (err >= 0)
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			err = nfs_delegation_claim_locks(ctx, state);
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		put_nfs_open_context(ctx);
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		if (err != 0)
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			return err;
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		goto again;
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	}
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	spin_unlock(&inode->i_lock);
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	return 0;
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}
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/**
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 * nfs_inode_reclaim_delegation - process a delegation reclaim request
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 * @inode: inode to process
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 * @cred: credential to use for request
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 * @res: new delegation state from server
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 *
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 */
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void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred,
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				  struct nfs_openres *res)
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{
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	struct nfs_delegation *delegation;
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	struct rpc_cred *oldcred = NULL;
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	rcu_read_lock();
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	delegation = rcu_dereference(NFS_I(inode)->delegation);
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	if (delegation != NULL) {
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		spin_lock(&delegation->lock);
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		if (delegation->inode != NULL) {
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			memcpy(delegation->stateid.data, res->delegation.data,
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			       sizeof(delegation->stateid.data));
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			delegation->type = res->delegation_type;
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			delegation->maxsize = res->maxsize;
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			oldcred = delegation->cred;
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			delegation->cred = get_rpccred(cred);
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			clear_bit(NFS_DELEGATION_NEED_RECLAIM,
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				  &delegation->flags);
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			NFS_I(inode)->delegation_state = delegation->type;
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			spin_unlock(&delegation->lock);
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			put_rpccred(oldcred);
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			rcu_read_unlock();
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		} else {
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			/* We appear to have raced with a delegation return. */
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			spin_unlock(&delegation->lock);
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			rcu_read_unlock();
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			nfs_inode_set_delegation(inode, cred, res);
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		}
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	} else {
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		rcu_read_unlock();
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	}
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}
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static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
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{
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	int res = 0;
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	res = nfs4_proc_delegreturn(inode, delegation->cred, &delegation->stateid, issync);
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	nfs_free_delegation(delegation);
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	return res;
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}
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static struct inode *nfs_delegation_grab_inode(struct nfs_delegation *delegation)
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{
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	struct inode *inode = NULL;
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	spin_lock(&delegation->lock);
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	if (delegation->inode != NULL)
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		inode = igrab(delegation->inode);
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	spin_unlock(&delegation->lock);
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	return inode;
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}
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static struct nfs_delegation *
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nfs_detach_delegation_locked(struct nfs_inode *nfsi,
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			     struct nfs_server *server)
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{
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	struct nfs_delegation *delegation =
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		rcu_dereference_protected(nfsi->delegation,
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				lockdep_is_held(&server->nfs_client->cl_lock));
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	if (delegation == NULL)
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		goto nomatch;
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	spin_lock(&delegation->lock);
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	list_del_rcu(&delegation->super_list);
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	delegation->inode = NULL;
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	nfsi->delegation_state = 0;
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	rcu_assign_pointer(nfsi->delegation, NULL);
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	spin_unlock(&delegation->lock);
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	return delegation;
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nomatch:
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	return NULL;
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}
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static struct nfs_delegation *nfs_detach_delegation(struct nfs_inode *nfsi,
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						    struct nfs_server *server)
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{
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	struct nfs_client *clp = server->nfs_client;
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	struct nfs_delegation *delegation;
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	spin_lock(&clp->cl_lock);
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	delegation = nfs_detach_delegation_locked(nfsi, server);
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	spin_unlock(&clp->cl_lock);
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	return delegation;
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}
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/**
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 * nfs_inode_set_delegation - set up a delegation on an inode
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 * @inode: inode to which delegation applies
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 * @cred: cred to use for subsequent delegation processing
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 * @res: new delegation state from server
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 *
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 * Returns zero on success, or a negative errno value.
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 */
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int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res)
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{
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	struct nfs_server *server = NFS_SERVER(inode);
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	struct nfs_client *clp = server->nfs_client;
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	struct nfs_inode *nfsi = NFS_I(inode);
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	struct nfs_delegation *delegation, *old_delegation;
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	struct nfs_delegation *freeme = NULL;
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	int status = 0;
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	delegation = kmalloc(sizeof(*delegation), GFP_NOFS);
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	if (delegation == NULL)
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		return -ENOMEM;
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	memcpy(delegation->stateid.data, res->delegation.data,
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			sizeof(delegation->stateid.data));
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	delegation->type = res->delegation_type;
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	delegation->maxsize = res->maxsize;
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	delegation->change_attr = inode->i_version;
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	delegation->cred = get_rpccred(cred);
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	delegation->inode = inode;
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	delegation->flags = 1<<NFS_DELEGATION_REFERENCED;
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	spin_lock_init(&delegation->lock);
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	spin_lock(&clp->cl_lock);
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	old_delegation = rcu_dereference_protected(nfsi->delegation,
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					lockdep_is_held(&clp->cl_lock));
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	if (old_delegation != NULL) {
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		if (memcmp(&delegation->stateid, &old_delegation->stateid,
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					sizeof(old_delegation->stateid)) == 0 &&
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				delegation->type == old_delegation->type) {
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			goto out;
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		}
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		/*
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		 * Deal with broken servers that hand out two
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		 * delegations for the same file.
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		 */
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		dfprintk(FILE, "%s: server %s handed out "
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				"a duplicate delegation!\n",
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				__func__, clp->cl_hostname);
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		if (delegation->type <= old_delegation->type) {
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			freeme = delegation;
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			delegation = NULL;
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			goto out;
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		}
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		freeme = nfs_detach_delegation_locked(nfsi, server);
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	}
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	list_add_rcu(&delegation->super_list, &server->delegations);
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	nfsi->delegation_state = delegation->type;
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	rcu_assign_pointer(nfsi->delegation, delegation);
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	delegation = NULL;
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	/* Ensure we revalidate the attributes and page cache! */
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	spin_lock(&inode->i_lock);
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	nfsi->cache_validity |= NFS_INO_REVAL_FORCED;
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	spin_unlock(&inode->i_lock);
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out:
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	spin_unlock(&clp->cl_lock);
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	if (delegation != NULL)
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		nfs_free_delegation(delegation);
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	if (freeme != NULL)
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		nfs_do_return_delegation(inode, freeme, 0);
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	return status;
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}
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/*
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 * Basic procedure for returning a delegation to the server
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 */
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static int __nfs_inode_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
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{
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	struct nfs_inode *nfsi = NFS_I(inode);
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	int err;
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	/*
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	 * Guard against new delegated open/lock/unlock calls and against
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	 * state recovery
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	 */
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	down_write(&nfsi->rwsem);
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	err = nfs_delegation_claim_opens(inode, &delegation->stateid);
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	up_write(&nfsi->rwsem);
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	if (err)
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		goto out;
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	err = nfs_do_return_delegation(inode, delegation, issync);
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out:
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	return err;
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}
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/**
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 * nfs_client_return_marked_delegations - return previously marked delegations
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 * @clp: nfs_client to process
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 *
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 * Returns zero on success, or a negative errno value.
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 */
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int nfs_client_return_marked_delegations(struct nfs_client *clp)
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{
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	struct nfs_delegation *delegation;
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	struct nfs_server *server;
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	struct inode *inode;
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	int err = 0;
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restart:
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	rcu_read_lock();
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	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
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		list_for_each_entry_rcu(delegation, &server->delegations,
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								super_list) {
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			if (!test_and_clear_bit(NFS_DELEGATION_RETURN,
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							&delegation->flags))
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				continue;
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			inode = nfs_delegation_grab_inode(delegation);
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			if (inode == NULL)
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				continue;
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			delegation = nfs_detach_delegation(NFS_I(inode),
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								server);
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			rcu_read_unlock();
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			if (delegation != NULL) {
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				filemap_flush(inode->i_mapping);
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				err = __nfs_inode_return_delegation(inode,
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								delegation, 0);
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			}
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			iput(inode);
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			if (!err)
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				goto restart;
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			set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
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			return err;
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		}
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	}
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	rcu_read_unlock();
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	return 0;
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}
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/**
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 * nfs_inode_return_delegation_noreclaim - return delegation, don't reclaim opens
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 * @inode: inode to process
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 *
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 * Does not protect against delegation reclaims, therefore really only safe
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 * to be called from nfs4_clear_inode().
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 */
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void nfs_inode_return_delegation_noreclaim(struct inode *inode)
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{
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	struct nfs_server *server = NFS_SERVER(inode);
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	struct nfs_inode *nfsi = NFS_I(inode);
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	struct nfs_delegation *delegation;
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	if (rcu_access_pointer(nfsi->delegation) != NULL) {
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		delegation = nfs_detach_delegation(nfsi, server);
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		if (delegation != NULL)
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			nfs_do_return_delegation(inode, delegation, 0);
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	}
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}
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/**
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 * nfs_inode_return_delegation - synchronously return a delegation
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 * @inode: inode to process
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 *
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 * Returns zero on success, or a negative errno value.
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 */
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int nfs_inode_return_delegation(struct inode *inode)
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{
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	struct nfs_server *server = NFS_SERVER(inode);
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	struct nfs_inode *nfsi = NFS_I(inode);
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	struct nfs_delegation *delegation;
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	int err = 0;
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	if (rcu_access_pointer(nfsi->delegation) != NULL) {
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		delegation = nfs_detach_delegation(nfsi, server);
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		if (delegation != NULL) {
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			nfs_wb_all(inode);
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			err = __nfs_inode_return_delegation(inode, delegation, 1);
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		}
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	}
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	return err;
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}
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static void nfs_mark_return_delegation(struct nfs_server *server,
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		struct nfs_delegation *delegation)
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{
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	set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
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	set_bit(NFS4CLNT_DELEGRETURN, &server->nfs_client->cl_state);
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}
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/**
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 * nfs_super_return_all_delegations - return delegations for one superblock
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 * @sb: sb to process
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 *
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 */
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void nfs_super_return_all_delegations(struct super_block *sb)
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{
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	struct nfs_server *server = NFS_SB(sb);
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	struct nfs_client *clp = server->nfs_client;
 | 
						|
	struct nfs_delegation *delegation;
 | 
						|
 | 
						|
	if (clp == NULL)
 | 
						|
		return;
 | 
						|
 | 
						|
	rcu_read_lock();
 | 
						|
	list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
 | 
						|
		spin_lock(&delegation->lock);
 | 
						|
		set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
 | 
						|
		spin_unlock(&delegation->lock);
 | 
						|
	}
 | 
						|
	rcu_read_unlock();
 | 
						|
 | 
						|
	if (nfs_client_return_marked_delegations(clp) != 0)
 | 
						|
		nfs4_schedule_state_manager(clp);
 | 
						|
}
 | 
						|
 | 
						|
static void nfs_mark_return_all_delegation_types(struct nfs_server *server,
 | 
						|
						 fmode_t flags)
 | 
						|
{
 | 
						|
	struct nfs_delegation *delegation;
 | 
						|
 | 
						|
	list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
 | 
						|
		if ((delegation->type == (FMODE_READ|FMODE_WRITE)) && !(flags & FMODE_WRITE))
 | 
						|
			continue;
 | 
						|
		if (delegation->type & flags)
 | 
						|
			nfs_mark_return_delegation(server, delegation);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
static void nfs_client_mark_return_all_delegation_types(struct nfs_client *clp,
 | 
						|
							fmode_t flags)
 | 
						|
{
 | 
						|
	struct nfs_server *server;
 | 
						|
 | 
						|
	rcu_read_lock();
 | 
						|
	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
 | 
						|
		nfs_mark_return_all_delegation_types(server, flags);
 | 
						|
	rcu_read_unlock();
 | 
						|
}
 | 
						|
 | 
						|
static void nfs_client_mark_return_all_delegations(struct nfs_client *clp)
 | 
						|
{
 | 
						|
	nfs_client_mark_return_all_delegation_types(clp, FMODE_READ|FMODE_WRITE);
 | 
						|
}
 | 
						|
 | 
						|
static void nfs_delegation_run_state_manager(struct nfs_client *clp)
 | 
						|
{
 | 
						|
	if (test_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state))
 | 
						|
		nfs4_schedule_state_manager(clp);
 | 
						|
}
 | 
						|
 | 
						|
void nfs_remove_bad_delegation(struct inode *inode)
 | 
						|
{
 | 
						|
	struct nfs_delegation *delegation;
 | 
						|
 | 
						|
	delegation = nfs_detach_delegation(NFS_I(inode), NFS_SERVER(inode));
 | 
						|
	if (delegation) {
 | 
						|
		nfs_inode_find_state_and_recover(inode, &delegation->stateid);
 | 
						|
		nfs_free_delegation(delegation);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * nfs_expire_all_delegation_types
 | 
						|
 * @clp: client to process
 | 
						|
 * @flags: delegation types to expire
 | 
						|
 *
 | 
						|
 */
 | 
						|
void nfs_expire_all_delegation_types(struct nfs_client *clp, fmode_t flags)
 | 
						|
{
 | 
						|
	nfs_client_mark_return_all_delegation_types(clp, flags);
 | 
						|
	nfs_delegation_run_state_manager(clp);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * nfs_expire_all_delegations
 | 
						|
 * @clp: client to process
 | 
						|
 *
 | 
						|
 */
 | 
						|
void nfs_expire_all_delegations(struct nfs_client *clp)
 | 
						|
{
 | 
						|
	nfs_expire_all_delegation_types(clp, FMODE_READ|FMODE_WRITE);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * nfs_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
 | 
						|
 * @clp: client to process
 | 
						|
 *
 | 
						|
 */
 | 
						|
void nfs_handle_cb_pathdown(struct nfs_client *clp)
 | 
						|
{
 | 
						|
	if (clp == NULL)
 | 
						|
		return;
 | 
						|
	nfs_client_mark_return_all_delegations(clp);
 | 
						|
}
 | 
						|
 | 
						|
static void nfs_mark_return_unreferenced_delegations(struct nfs_server *server)
 | 
						|
{
 | 
						|
	struct nfs_delegation *delegation;
 | 
						|
 | 
						|
	list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
 | 
						|
		if (test_and_clear_bit(NFS_DELEGATION_REFERENCED, &delegation->flags))
 | 
						|
			continue;
 | 
						|
		nfs_mark_return_delegation(server, delegation);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * nfs_expire_unreferenced_delegations - Eliminate unused delegations
 | 
						|
 * @clp: nfs_client to process
 | 
						|
 *
 | 
						|
 */
 | 
						|
void nfs_expire_unreferenced_delegations(struct nfs_client *clp)
 | 
						|
{
 | 
						|
	struct nfs_server *server;
 | 
						|
 | 
						|
	rcu_read_lock();
 | 
						|
	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
 | 
						|
		nfs_mark_return_unreferenced_delegations(server);
 | 
						|
	rcu_read_unlock();
 | 
						|
 | 
						|
	nfs_delegation_run_state_manager(clp);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * nfs_async_inode_return_delegation - asynchronously return a delegation
 | 
						|
 * @inode: inode to process
 | 
						|
 * @stateid: state ID information
 | 
						|
 *
 | 
						|
 * Returns zero on success, or a negative errno value.
 | 
						|
 */
 | 
						|
int nfs_async_inode_return_delegation(struct inode *inode,
 | 
						|
				      const nfs4_stateid *stateid)
 | 
						|
{
 | 
						|
	struct nfs_server *server = NFS_SERVER(inode);
 | 
						|
	struct nfs_client *clp = server->nfs_client;
 | 
						|
	struct nfs_delegation *delegation;
 | 
						|
 | 
						|
	rcu_read_lock();
 | 
						|
	delegation = rcu_dereference(NFS_I(inode)->delegation);
 | 
						|
 | 
						|
	if (!clp->cl_mvops->match_stateid(&delegation->stateid, stateid)) {
 | 
						|
		rcu_read_unlock();
 | 
						|
		return -ENOENT;
 | 
						|
	}
 | 
						|
	nfs_mark_return_delegation(server, delegation);
 | 
						|
	rcu_read_unlock();
 | 
						|
 | 
						|
	nfs_delegation_run_state_manager(clp);
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
static struct inode *
 | 
						|
nfs_delegation_find_inode_server(struct nfs_server *server,
 | 
						|
				 const struct nfs_fh *fhandle)
 | 
						|
{
 | 
						|
	struct nfs_delegation *delegation;
 | 
						|
	struct inode *res = NULL;
 | 
						|
 | 
						|
	list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
 | 
						|
		spin_lock(&delegation->lock);
 | 
						|
		if (delegation->inode != NULL &&
 | 
						|
		    nfs_compare_fh(fhandle, &NFS_I(delegation->inode)->fh) == 0) {
 | 
						|
			res = igrab(delegation->inode);
 | 
						|
		}
 | 
						|
		spin_unlock(&delegation->lock);
 | 
						|
		if (res != NULL)
 | 
						|
			break;
 | 
						|
	}
 | 
						|
	return res;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * nfs_delegation_find_inode - retrieve the inode associated with a delegation
 | 
						|
 * @clp: client state handle
 | 
						|
 * @fhandle: filehandle from a delegation recall
 | 
						|
 *
 | 
						|
 * Returns pointer to inode matching "fhandle," or NULL if a matching inode
 | 
						|
 * cannot be found.
 | 
						|
 */
 | 
						|
struct inode *nfs_delegation_find_inode(struct nfs_client *clp,
 | 
						|
					const struct nfs_fh *fhandle)
 | 
						|
{
 | 
						|
	struct nfs_server *server;
 | 
						|
	struct inode *res = NULL;
 | 
						|
 | 
						|
	rcu_read_lock();
 | 
						|
	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 | 
						|
		res = nfs_delegation_find_inode_server(server, fhandle);
 | 
						|
		if (res != NULL)
 | 
						|
			break;
 | 
						|
	}
 | 
						|
	rcu_read_unlock();
 | 
						|
	return res;
 | 
						|
}
 | 
						|
 | 
						|
static void nfs_delegation_mark_reclaim_server(struct nfs_server *server)
 | 
						|
{
 | 
						|
	struct nfs_delegation *delegation;
 | 
						|
 | 
						|
	list_for_each_entry_rcu(delegation, &server->delegations, super_list)
 | 
						|
		set_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * nfs_delegation_mark_reclaim - mark all delegations as needing to be reclaimed
 | 
						|
 * @clp: nfs_client to process
 | 
						|
 *
 | 
						|
 */
 | 
						|
void nfs_delegation_mark_reclaim(struct nfs_client *clp)
 | 
						|
{
 | 
						|
	struct nfs_server *server;
 | 
						|
 | 
						|
	rcu_read_lock();
 | 
						|
	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
 | 
						|
		nfs_delegation_mark_reclaim_server(server);
 | 
						|
	rcu_read_unlock();
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * nfs_delegation_reap_unclaimed - reap unclaimed delegations after reboot recovery is done
 | 
						|
 * @clp: nfs_client to process
 | 
						|
 *
 | 
						|
 */
 | 
						|
void nfs_delegation_reap_unclaimed(struct nfs_client *clp)
 | 
						|
{
 | 
						|
	struct nfs_delegation *delegation;
 | 
						|
	struct nfs_server *server;
 | 
						|
	struct inode *inode;
 | 
						|
 | 
						|
restart:
 | 
						|
	rcu_read_lock();
 | 
						|
	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 | 
						|
		list_for_each_entry_rcu(delegation, &server->delegations,
 | 
						|
								super_list) {
 | 
						|
			if (test_bit(NFS_DELEGATION_NEED_RECLAIM,
 | 
						|
						&delegation->flags) == 0)
 | 
						|
				continue;
 | 
						|
			inode = nfs_delegation_grab_inode(delegation);
 | 
						|
			if (inode == NULL)
 | 
						|
				continue;
 | 
						|
			delegation = nfs_detach_delegation(NFS_I(inode),
 | 
						|
								server);
 | 
						|
			rcu_read_unlock();
 | 
						|
 | 
						|
			if (delegation != NULL)
 | 
						|
				nfs_free_delegation(delegation);
 | 
						|
			iput(inode);
 | 
						|
			goto restart;
 | 
						|
		}
 | 
						|
	}
 | 
						|
	rcu_read_unlock();
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * nfs_delegations_present - check for existence of delegations
 | 
						|
 * @clp: client state handle
 | 
						|
 *
 | 
						|
 * Returns one if there are any nfs_delegation structures attached
 | 
						|
 * to this nfs_client.
 | 
						|
 */
 | 
						|
int nfs_delegations_present(struct nfs_client *clp)
 | 
						|
{
 | 
						|
	struct nfs_server *server;
 | 
						|
	int ret = 0;
 | 
						|
 | 
						|
	rcu_read_lock();
 | 
						|
	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
 | 
						|
		if (!list_empty(&server->delegations)) {
 | 
						|
			ret = 1;
 | 
						|
			break;
 | 
						|
		}
 | 
						|
	rcu_read_unlock();
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * nfs4_copy_delegation_stateid - Copy inode's state ID information
 | 
						|
 * @dst: stateid data structure to fill in
 | 
						|
 * @inode: inode to check
 | 
						|
 *
 | 
						|
 * Returns one and fills in "dst->data" * if inode had a delegation,
 | 
						|
 * otherwise zero is returned.
 | 
						|
 */
 | 
						|
int nfs4_copy_delegation_stateid(nfs4_stateid *dst, struct inode *inode)
 | 
						|
{
 | 
						|
	struct nfs_inode *nfsi = NFS_I(inode);
 | 
						|
	struct nfs_delegation *delegation;
 | 
						|
	int ret = 0;
 | 
						|
 | 
						|
	rcu_read_lock();
 | 
						|
	delegation = rcu_dereference(nfsi->delegation);
 | 
						|
	if (delegation != NULL) {
 | 
						|
		memcpy(dst->data, delegation->stateid.data, sizeof(dst->data));
 | 
						|
		ret = 1;
 | 
						|
	}
 | 
						|
	rcu_read_unlock();
 | 
						|
	return ret;
 | 
						|
}
 |