Commit fdd1e74c authored by Trond Myklebust's avatar Trond Myklebust
Browse files

NFS: Ensure that the read code cleans up properly when rpc_run_task() fails 



In the case of readpage() we need to ensure that the pages get unlocked,
and that the error is flagged.

In the case of O_DIRECT, we need to ensure that the pages are all released.

Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 73e3302f

fs/nfs/direct.c

+13 −6
Original line number Diff line number Diff line
@@ -229,14 +229,20 @@ static void nfs_direct_complete(struct nfs_direct_req *dreq) 
static void nfs_direct_read_result(struct rpc_task *task, void *calldata)

{

	struct nfs_read_data *data = calldata;

	struct nfs_direct_req *dreq = (struct nfs_direct_req *) data->req;



	if (nfs_readpage_result(task, data) != 0)

		return;

	nfs_readpage_result(task, data);

}



static void nfs_direct_read_release(void *calldata)

{



	struct nfs_read_data *data = calldata;

	struct nfs_direct_req *dreq = (struct nfs_direct_req *) data->req;

	int status = data->task.tk_status;



	spin_lock(&dreq->lock);

	if (unlikely(task->tk_status < 0)) {

		dreq->error = task->tk_status;

	if (unlikely(status < 0)) {

		dreq->error = status;

		spin_unlock(&dreq->lock);

	} else {

		dreq->count += data->res.count;
@@ -249,11 +255,12 @@ static void nfs_direct_read_result(struct rpc_task *task, void *calldata) 


	if (put_dreq(dreq))

		nfs_direct_complete(dreq);

	nfs_readdata_release(calldata);

}



static const struct rpc_call_ops nfs_read_direct_ops = {

	.rpc_call_done = nfs_direct_read_result,

	.rpc_release = nfs_readdata_release,

	.rpc_release = nfs_direct_read_release,

};



/*

fs/nfs/read.c

+33 −20
Original line number Diff line number Diff line
@@ -338,26 +338,25 @@ int nfs_readpage_result(struct rpc_task *task, struct nfs_read_data *data) 
	return 0;

}



static int nfs_readpage_retry(struct rpc_task *task, struct nfs_read_data *data)

static void nfs_readpage_retry(struct rpc_task *task, struct nfs_read_data *data)

{

	struct nfs_readargs *argp = &data->args;

	struct nfs_readres *resp = &data->res;



	if (resp->eof || resp->count == argp->count)

		return 0;

		return;



	/* This is a short read! */

	nfs_inc_stats(data->inode, NFSIOS_SHORTREAD);

	/* Has the server at least made some progress? */

	if (resp->count == 0)

		return 0;

		return;



	/* Yes, so retry the read at the end of the data */

	argp->offset += resp->count;

	argp->pgbase += resp->count;

	argp->count -= resp->count;

	rpc_restart_call(task);

	return -EAGAIN;

}



/*
@@ -366,29 +365,37 @@ static int nfs_readpage_retry(struct rpc_task *task, struct nfs_read_data *data) 
static void nfs_readpage_result_partial(struct rpc_task *task, void *calldata)

{

	struct nfs_read_data *data = calldata;

	struct nfs_page *req = data->req;

	struct page *page = req->wb_page;

 

	if (nfs_readpage_result(task, data) != 0)

		return;

	if (task->tk_status < 0)

		return;



	if (likely(task->tk_status >= 0)) {

	nfs_readpage_truncate_uninitialised_page(data);

		if (nfs_readpage_retry(task, data) != 0)

			return;

	nfs_readpage_retry(task, data);

}

	if (unlikely(task->tk_status < 0))



static void nfs_readpage_release_partial(void *calldata)

{

	struct nfs_read_data *data = calldata;

	struct nfs_page *req = data->req;

	struct page *page = req->wb_page;

	int status = data->task.tk_status;



	if (status < 0)

		SetPageError(page);



	if (atomic_dec_and_test(&req->wb_complete)) {

		if (!PageError(page))

			SetPageUptodate(page);

		nfs_readpage_release(req);

	}

	nfs_readdata_release(calldata);

}



static const struct rpc_call_ops nfs_read_partial_ops = {

	.rpc_call_done = nfs_readpage_result_partial,

	.rpc_release = nfs_readdata_release,

	.rpc_release = nfs_readpage_release_partial,

};



static void nfs_readpage_set_pages_uptodate(struct nfs_read_data *data)
@@ -423,29 +430,35 @@ static void nfs_readpage_result_full(struct rpc_task *task, void *calldata) 


	if (nfs_readpage_result(task, data) != 0)

		return;

	if (task->tk_status < 0)

		return;

	/*

	 * Note: nfs_readpage_retry may change the values of

	 * data->args. In the multi-page case, we therefore need

	 * to ensure that we call nfs_readpage_set_pages_uptodate()

	 * first.

	 */

	if (likely(task->tk_status >= 0)) {

	nfs_readpage_truncate_uninitialised_page(data);

	nfs_readpage_set_pages_uptodate(data);

		if (nfs_readpage_retry(task, data) != 0)

			return;

	nfs_readpage_retry(task, data);

}



static void nfs_readpage_release_full(void *calldata)

{

	struct nfs_read_data *data = calldata;



	while (!list_empty(&data->pages)) {

		struct nfs_page *req = nfs_list_entry(data->pages.next);



		nfs_list_remove_request(req);

		nfs_readpage_release(req);

	}

	nfs_readdata_release(calldata);

}



static const struct rpc_call_ops nfs_read_full_ops = {

	.rpc_call_done = nfs_readpage_result_full,

	.rpc_release = nfs_readdata_release,

	.rpc_release = nfs_readpage_release_full,

};



/*