Commit 226056c5 authored by Trond Myklebust's avatar Trond Myklebust
Browse files

NFSv4: Use correct locking when updating nfs4_state in nfs4_close_done 



The stateid and state->flags should be updated atomically under
protection of the state->seqlock.

Signed-off-by: default avatarTrond Myklebust <trond.myklebust@primarydata.com>
parent 78096cca

fs/nfs/nfs4proc.c

+35 −30
Original line number Diff line number Diff line
@@ -1149,6 +1149,38 @@ static bool nfs_need_update_open_stateid(struct nfs4_state *state, 
	return false;

}



static void nfs_clear_open_stateid_locked(struct nfs4_state *state,

		nfs4_stateid *stateid, fmode_t fmode)

{

	clear_bit(NFS_O_RDWR_STATE, &state->flags);

	switch (fmode & (FMODE_READ|FMODE_WRITE)) {

	case FMODE_WRITE:

		clear_bit(NFS_O_RDONLY_STATE, &state->flags);

		break;

	case FMODE_READ:

		clear_bit(NFS_O_WRONLY_STATE, &state->flags);

		break;

	case 0:

		clear_bit(NFS_O_RDONLY_STATE, &state->flags);

		clear_bit(NFS_O_WRONLY_STATE, &state->flags);

		clear_bit(NFS_OPEN_STATE, &state->flags);

	}

	if (stateid == NULL)

		return;

	if (!nfs_need_update_open_stateid(state, stateid))

		return;

	if (test_bit(NFS_DELEGATED_STATE, &state->flags) == 0)

		nfs4_stateid_copy(&state->stateid, stateid);

	nfs4_stateid_copy(&state->open_stateid, stateid);

}



static void nfs_clear_open_stateid(struct nfs4_state *state, nfs4_stateid *stateid, fmode_t fmode)

{

	write_seqlock(&state->seqlock);

	nfs_clear_open_stateid_locked(state, stateid, fmode);

	write_sequnlock(&state->seqlock);

}



static void nfs_set_open_stateid_locked(struct nfs4_state *state, nfs4_stateid *stateid, fmode_t fmode)

{

	switch (fmode) {
@@ -1168,13 +1200,6 @@ static void nfs_set_open_stateid_locked(struct nfs4_state *state, nfs4_stateid * 
	nfs4_stateid_copy(&state->open_stateid, stateid);

}



static void nfs_set_open_stateid(struct nfs4_state *state, nfs4_stateid *stateid, fmode_t fmode)

{

	write_seqlock(&state->seqlock);

	nfs_set_open_stateid_locked(state, stateid, fmode);

	write_sequnlock(&state->seqlock);

}



static void __update_open_stateid(struct nfs4_state *state, nfs4_stateid *open_stateid, const nfs4_stateid *deleg_stateid, fmode_t fmode)

{

	/*
@@ -2489,26 +2514,6 @@ static void nfs4_free_closedata(void *data) 
	kfree(calldata);

}



static void nfs4_close_clear_stateid_flags(struct nfs4_state *state,

		fmode_t fmode)

{

	spin_lock(&state->owner->so_lock);

	clear_bit(NFS_O_RDWR_STATE, &state->flags);

	switch (fmode & (FMODE_READ|FMODE_WRITE)) {

	case FMODE_WRITE:

		clear_bit(NFS_O_RDONLY_STATE, &state->flags);

		break;

	case FMODE_READ:

		clear_bit(NFS_O_WRONLY_STATE, &state->flags);

		break;

	case 0:

		clear_bit(NFS_O_RDONLY_STATE, &state->flags);

		clear_bit(NFS_O_WRONLY_STATE, &state->flags);

		clear_bit(NFS_OPEN_STATE, &state->flags);

	}

	spin_unlock(&state->owner->so_lock);

}



static void nfs4_close_done(struct rpc_task *task, void *data)

{

	struct nfs4_closedata *calldata = data;
@@ -2527,9 +2532,9 @@ static void nfs4_close_done(struct rpc_task *task, void *data) 
			if (calldata->roc)

				pnfs_roc_set_barrier(state->inode,

						     calldata->roc_barrier);

			nfs_set_open_stateid(state, &calldata->res.stateid, 0);

			nfs_clear_open_stateid(state, &calldata->res.stateid, 0);

			renew_lease(server, calldata->timestamp);

			break;

			goto out_release;

		case -NFS4ERR_ADMIN_REVOKED:

		case -NFS4ERR_STALE_STATEID:

		case -NFS4ERR_OLD_STATEID:
@@ -2543,7 +2548,7 @@ static void nfs4_close_done(struct rpc_task *task, void *data) 
				goto out_release;

			}

	}

	nfs4_close_clear_stateid_flags(state, calldata->arg.fmode);

	nfs_clear_open_stateid(state, NULL, calldata->arg.fmode);

out_release:

	nfs_release_seqid(calldata->arg.seqid);

	nfs_refresh_inode(calldata->inode, calldata->res.fattr);