Commit e6e21970 authored by Trond Myklebust's avatar Trond Myklebust
Browse files

NFSv4: Fix open_to_lock_owner sequenceid allocation... 



NFSv4 file locking is currently completely broken since it doesn't respect
the OPEN sequencing when it is given an unconfirmed lock_owner and needs to
do an open_to_lock_owner. Worse: it breaks the sunrpc rules by doing a
GFP_KERNEL allocation inside an rpciod callback.

Fix is to preallocate the open seqid structure in nfs4_alloc_lockdata if we
see that the lock_owner is unconfirmed.
Then, in nfs4_lock_prepare() we wait for either the open_seqid, if
the lock_owner is still unconfirmed, or else fall back to waiting on the
standard lock_seqid.

Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent bb22629e

fs/nfs/nfs4proc.c

+19 −11
Original line number Diff line number Diff line
@@ -3331,6 +3331,12 @@ static struct nfs4_lockdata *nfs4_alloc_lockdata(struct file_lock *fl, 


	p->arg.fh = NFS_FH(inode);

	p->arg.fl = &p->fl;

	if (!(lsp->ls_seqid.flags & NFS_SEQID_CONFIRMED)) {

		p->arg.open_seqid = nfs_alloc_seqid(&lsp->ls_state->owner->so_seqid);

		if (p->arg.open_seqid == NULL)

			goto out_free;



	}

	p->arg.lock_seqid = nfs_alloc_seqid(&lsp->ls_seqid);

	if (p->arg.lock_seqid == NULL)

		goto out_free;
@@ -3343,6 +3349,8 @@ static struct nfs4_lockdata *nfs4_alloc_lockdata(struct file_lock *fl, 
	memcpy(&p->fl, fl, sizeof(p->fl));

	return p;

out_free:

	if (p->arg.open_seqid != NULL)

		nfs_free_seqid(p->arg.open_seqid);

	kfree(p);

	return NULL;

}
@@ -3359,23 +3367,23 @@ static void nfs4_lock_prepare(struct rpc_task *task, void *calldata) 
		.rpc_cred = sp->so_cred,

	};



	if (nfs_wait_on_sequence(data->arg.lock_seqid, task) != 0)

		return;

	dprintk("%s: begin!\n", __FUNCTION__);

	/* Do we need to do an open_to_lock_owner? */

	if (!(data->arg.lock_seqid->sequence->flags & NFS_SEQID_CONFIRMED)) {

		data->arg.open_seqid = nfs_alloc_seqid(&sp->so_seqid);

		if (data->arg.open_seqid == NULL) {

			data->rpc_status = -ENOMEM;

			task->tk_action = NULL;

			goto out;

		}

		if (nfs_wait_on_sequence(data->arg.open_seqid, task) != 0)

			return;

		data->arg.open_stateid = &state->stateid;

		data->arg.new_lock_owner = 1;

		/* Retest in case we raced... */

		if (!(data->arg.lock_seqid->sequence->flags & NFS_SEQID_CONFIRMED))

			goto do_rpc;

	}

	if (nfs_wait_on_sequence(data->arg.lock_seqid, task) != 0)

		return;

	data->arg.new_lock_owner = 0;

do_rpc:	

	data->timestamp = jiffies;

	rpc_call_setup(task, &msg, 0);

out:

	dprintk("%s: done!, ret = %d\n", __FUNCTION__, data->rpc_status);

}
@@ -3411,8 +3419,6 @@ static void nfs4_lock_release(void *calldata) 
	struct nfs4_lockdata *data = calldata;



	dprintk("%s: begin!\n", __FUNCTION__);

	if (data->arg.open_seqid != NULL)

		nfs_free_seqid(data->arg.open_seqid);

	if (data->cancelled != 0) {

		struct rpc_task *task;

		task = nfs4_do_unlck(&data->fl, data->ctx, data->lsp,
@@ -3422,6 +3428,8 @@ static void nfs4_lock_release(void *calldata) 
		dprintk("%s: cancelling lock!\n", __FUNCTION__);

	} else

		nfs_free_seqid(data->arg.lock_seqid);

	if (data->arg.open_seqid != NULL)

		nfs_free_seqid(data->arg.open_seqid);

	nfs4_put_lock_state(data->lsp);

	put_nfs_open_context(data->ctx);

	kfree(data);

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