Commit 98d5c7c5 authored by Jeff Layton's avatar Jeff Layton Committed by J. Bruce Fields
Browse files

nfsd: add more granular locking to *_delegations fault injectors 



...instead of relying on the client_mutex.

Signed-off-by: default avatarJeff Layton <jlayton@primarydata.com>
Signed-off-by: default avatarJ. Bruce Fields <bfields@redhat.com>
parent 82e05efa

fs/nfsd/fault_inject.c

+6 −10
Original line number Diff line number Diff line
@@ -152,19 +152,15 @@ static struct nfsd_fault_inject_op inject_ops[] = { 
	},

	{

		.file     = "forget_delegations",

		.get	  = nfsd_inject_get,

		.set_val  = nfsd_inject_set,

		.set_clnt = nfsd_inject_set_client,

		.forget   = nfsd_forget_client_delegations,

		.print    = nfsd_print_client_delegations,

		.get	  = nfsd_inject_print_delegations,

		.set_val  = nfsd_inject_forget_delegations,

		.set_clnt = nfsd_inject_forget_client_delegations,

	},

	{

		.file     = "recall_delegations",

		.get	  = nfsd_inject_get,

		.set_val  = nfsd_inject_set,

		.set_clnt = nfsd_inject_set_client,

		.forget   = nfsd_recall_client_delegations,

		.print    = nfsd_print_client_delegations,

		.get	  = nfsd_inject_print_delegations,

		.set_val  = nfsd_inject_recall_delegations,

		.set_clnt = nfsd_inject_recall_client_delegations,

	},

};

fs/nfsd/nfs4state.c

+149 −26
Original line number Diff line number Diff line
@@ -6102,9 +6102,13 @@ static u64 nfsd_find_all_delegations(struct nfs4_client *clp, u64 max, 
				     struct list_head *victims)

{

	struct nfs4_delegation *dp, *next;

	struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,

						nfsd_net_id);

	u64 count = 0;



	lockdep_assert_held(&state_lock);

	lockdep_assert_held(&nn->client_lock);



	spin_lock(&state_lock);

	list_for_each_entry_safe(dp, next, &clp->cl_delegations, dl_perclnt) {

		if (victims) {

			/*
@@ -6116,62 +6120,180 @@ static u64 nfsd_find_all_delegations(struct nfs4_client *clp, u64 max, 
			if (dp->dl_time != 0)

				continue;



			atomic_inc(&clp->cl_refcount);

			unhash_delegation_locked(dp);

			list_add(&dp->dl_recall_lru, victims);

		}

		if (++count == max)

		++count;

		/*

		 * Despite the fact that these functions deal with

		 * 64-bit integers for "count", we must ensure that

		 * it doesn't blow up the clp->cl_refcount. Throw a

		 * warning if we start to approach INT_MAX here.

		 */

		WARN_ON_ONCE(count == (INT_MAX / 2));

		if (count == max)

			break;

	}

	spin_unlock(&state_lock);

	return count;

}



static u64

nfsd_print_client_delegations(struct nfs4_client *clp)

{

	u64 count = nfsd_find_all_delegations(clp, 0, NULL);



	nfsd_print_count(clp, count, "delegations");

	return count;

}



u64 nfsd_forget_client_delegations(struct nfs4_client *clp, u64 max)

u64

nfsd_inject_print_delegations(struct nfsd_fault_inject_op *op)

{

	struct nfs4_delegation *dp, *next;

	LIST_HEAD(victims);

	u64 count;

	struct nfs4_client *clp;

	u64 count = 0;

	struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,

						nfsd_net_id);



	spin_lock(&state_lock);

	count = nfsd_find_all_delegations(clp, max, &victims);

	spin_unlock(&state_lock);

	if (!nfsd_netns_ready(nn))

		return 0;



	list_for_each_entry_safe(dp, next, &victims, dl_recall_lru) {

	spin_lock(&nn->client_lock);

	list_for_each_entry(clp, &nn->client_lru, cl_lru)

		count += nfsd_print_client_delegations(clp);

	spin_unlock(&nn->client_lock);



	return count;

}



static void

nfsd_forget_delegations(struct list_head *reaplist)

{

	struct nfs4_client *clp;

	struct nfs4_delegation *dp, *next;



	list_for_each_entry_safe(dp, next, reaplist, dl_recall_lru) {

		list_del_init(&dp->dl_recall_lru);

		clp = dp->dl_stid.sc_client;

		revoke_delegation(dp);

		put_client(clp);

	}

}



u64

nfsd_inject_forget_client_delegations(struct nfsd_fault_inject_op *op,

				struct sockaddr_storage *addr, size_t addr_size)

{

	u64 count = 0;

	struct nfs4_client *clp;

	struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,

						nfsd_net_id);

	LIST_HEAD(reaplist);



	if (!nfsd_netns_ready(nn))

		return count;



	spin_lock(&nn->client_lock);

	clp = nfsd_find_client(addr, addr_size);

	if (clp)

		count = nfsd_find_all_delegations(clp, 0, &reaplist);

	spin_unlock(&nn->client_lock);



	nfsd_forget_delegations(&reaplist);

	return count;

}



u64 nfsd_recall_client_delegations(struct nfs4_client *clp, u64 max)

u64

nfsd_inject_forget_delegations(struct nfsd_fault_inject_op *op, u64 max)

{

	struct nfs4_delegation *dp;

	LIST_HEAD(victims);

	u64 count;

	u64 count = 0;

	struct nfs4_client *clp;

	struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,

						nfsd_net_id);

	LIST_HEAD(reaplist);



	spin_lock(&state_lock);

	count = nfsd_find_all_delegations(clp, max, &victims);

	while (!list_empty(&victims)) {

		dp = list_first_entry(&victims, struct nfs4_delegation,

					dl_recall_lru);

	if (!nfsd_netns_ready(nn))

		return count;



	spin_lock(&nn->client_lock);

	list_for_each_entry(clp, &nn->client_lru, cl_lru) {

		count += nfsd_find_all_delegations(clp, max - count, &reaplist);

		if (max != 0 && count >= max)

			break;

	}

	spin_unlock(&nn->client_lock);

	nfsd_forget_delegations(&reaplist);

	return count;

}



static void

nfsd_recall_delegations(struct list_head *reaplist)

{

	struct nfs4_client *clp;

	struct nfs4_delegation *dp, *next;



	list_for_each_entry_safe(dp, next, reaplist, dl_recall_lru) {

		list_del_init(&dp->dl_recall_lru);

		clp = dp->dl_stid.sc_client;

		/*

		 * We skipped all entries that had a zero dl_time before,

		 * so we can now reset the dl_time back to 0. If a delegation

		 * break comes in now, then it won't make any difference since

		 * we're recalling it either way.

		 */

		spin_lock(&state_lock);

		dp->dl_time = 0;

		spin_unlock(&state_lock);

		nfsd_break_one_deleg(dp);

		put_client(clp);

	}

	spin_unlock(&state_lock);

}



u64

nfsd_inject_recall_client_delegations(struct nfsd_fault_inject_op *op,

				      struct sockaddr_storage *addr,

				      size_t addr_size)

{

	u64 count = 0;

	struct nfs4_client *clp;

	struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,

						nfsd_net_id);

	LIST_HEAD(reaplist);



	if (!nfsd_netns_ready(nn))

		return count;



	spin_lock(&nn->client_lock);

	clp = nfsd_find_client(addr, addr_size);

	if (clp)

		count = nfsd_find_all_delegations(clp, 0, &reaplist);

	spin_unlock(&nn->client_lock);



	nfsd_recall_delegations(&reaplist);

	return count;

}



u64 nfsd_print_client_delegations(struct nfs4_client *clp, u64 max)

u64

nfsd_inject_recall_delegations(struct nfsd_fault_inject_op *op, u64 max)

{

	u64 count = 0;

	struct nfs4_client *clp, *next;

	struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,

						nfsd_net_id);

	LIST_HEAD(reaplist);



	spin_lock(&state_lock);

	count = nfsd_find_all_delegations(clp, max, NULL);

	spin_unlock(&state_lock);

	if (!nfsd_netns_ready(nn))

		return count;



	nfsd_print_count(clp, count, "delegations");

	spin_lock(&nn->client_lock);

	list_for_each_entry_safe(clp, next, &nn->client_lru, cl_lru) {

		count += nfsd_find_all_delegations(clp, max - count, &reaplist);

		if (max != 0 && ++count >= max)

			break;

	}

	spin_unlock(&nn->client_lock);

	nfsd_recall_delegations(&reaplist);

	return count;

}
@@ -6179,7 +6301,8 @@ u64 nfsd_for_n_state(u64 max, u64 (*func)(struct nfs4_client *, u64)) 
{

	struct nfs4_client *clp, *next;

	u64 count = 0;

	struct nfsd_net *nn = net_generic(current->nsproxy->net_ns, nfsd_net_id);

	struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,

						nfsd_net_id);



	if (!nfsd_netns_ready(nn))

		return 0;

fs/nfsd/state.h

+7 −4
Original line number Diff line number Diff line
@@ -493,10 +493,13 @@ u64 nfsd_inject_forget_client_openowners(struct nfsd_fault_inject_op *, 
					 struct sockaddr_storage *, size_t);

u64 nfsd_inject_forget_openowners(struct nfsd_fault_inject_op *, u64);



u64 nfsd_forget_client_delegations(struct nfs4_client *, u64);

u64 nfsd_recall_client_delegations(struct nfs4_client *, u64);



u64 nfsd_print_client_delegations(struct nfs4_client *, u64);

u64 nfsd_inject_print_delegations(struct nfsd_fault_inject_op *);

u64 nfsd_inject_forget_client_delegations(struct nfsd_fault_inject_op *,

					  struct sockaddr_storage *, size_t);

u64 nfsd_inject_forget_delegations(struct nfsd_fault_inject_op *, u64);

u64 nfsd_inject_recall_client_delegations(struct nfsd_fault_inject_op *,

					  struct sockaddr_storage *, size_t);

u64 nfsd_inject_recall_delegations(struct nfsd_fault_inject_op *, u64);

#else /* CONFIG_NFSD_FAULT_INJECTION */

static inline int nfsd_fault_inject_init(void) { return 0; }

static inline void nfsd_fault_inject_cleanup(void) {}