Commit 7594bf37 authored by Al Viro's avatar Al Viro
Browse files

9p: untangle ->poll() mess 



First of all, NULL ->poll() means "always POLLIN, always POLLOUT", not an error.
Furthermore, mixing -EREMOTEIO with POLL... masks and expecting it to do anything
good is insane - both are arch-dependent, to start with.  Pass a pointer to
store the error value separately and make it return POLLERR in such case.

And ->poll() calling conventions do *not* include "return -Esomething".  Never
had.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 5dc533c6

net/9p/trans_fd.c

+30 −30
Original line number Diff line number Diff line
@@ -228,32 +228,31 @@ static void p9_conn_cancel(struct p9_conn *m, int err) 
	}

}



static int

p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt)

static __poll_t

p9_fd_poll(struct p9_client *client, struct poll_table_struct *pt, int *err)

{

	int ret, n;

	__poll_t ret, n;

	struct p9_trans_fd *ts = NULL;



	if (client && client->status == Connected)

		ts = client->trans;



	if (!ts)

		return -EREMOTEIO;

	if (!ts) {

		if (err)

			*err = -EREMOTEIO;

		return POLLERR;

	}



	if (!ts->rd->f_op->poll)

		return -EIO;



	if (!ts->wr->f_op->poll)

		return -EIO;



		ret = DEFAULT_POLLMASK;

	else

		ret = ts->rd->f_op->poll(ts->rd, pt);

	if (ret < 0)

		return ret;



	if (ts->rd != ts->wr) {

		if (!ts->wr->f_op->poll)

			n = DEFAULT_POLLMASK;

		else

			n = ts->wr->f_op->poll(ts->wr, pt);

		if (n < 0)

			return n;

		ret = (ret & ~POLLOUT) | (n & ~POLLIN);

	}
@@ -298,7 +297,8 @@ static int p9_fd_read(struct p9_client *client, void *v, int len) 


static void p9_read_work(struct work_struct *work)

{

	int n, err;

	__poll_t n;

	int err;

	struct p9_conn *m;

	int status = REQ_STATUS_ERROR;
@@ -398,7 +398,7 @@ end_clear: 
		if (test_and_clear_bit(Rpending, &m->wsched))

			n = POLLIN;

		else

			n = p9_fd_poll(m->client, NULL);

			n = p9_fd_poll(m->client, NULL, NULL);



		if ((n & POLLIN) && !test_and_set_bit(Rworksched, &m->wsched)) {

			p9_debug(P9_DEBUG_TRANS, "sched read work %p\n", m);
@@ -448,7 +448,8 @@ static int p9_fd_write(struct p9_client *client, void *v, int len) 


static void p9_write_work(struct work_struct *work)

{

	int n, err;

	__poll_t n;

	int err;

	struct p9_conn *m;

	struct p9_req_t *req;
@@ -506,7 +507,7 @@ end_clear: 
		if (test_and_clear_bit(Wpending, &m->wsched))

			n = POLLOUT;

		else

			n = p9_fd_poll(m->client, NULL);

			n = p9_fd_poll(m->client, NULL, NULL);



		if ((n & POLLOUT) &&

		   !test_and_set_bit(Wworksched, &m->wsched)) {
@@ -581,7 +582,7 @@ p9_pollwait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p) 


static void p9_conn_create(struct p9_client *client)

{

	int n;

	__poll_t n;

	struct p9_trans_fd *ts = client->trans;

	struct p9_conn *m = &ts->conn;
@@ -597,7 +598,7 @@ static void p9_conn_create(struct p9_client *client) 
	INIT_LIST_HEAD(&m->poll_pending_link);

	init_poll_funcptr(&m->pt, p9_pollwait);



	n = p9_fd_poll(client, &m->pt);

	n = p9_fd_poll(client, &m->pt, NULL);

	if (n & POLLIN) {

		p9_debug(P9_DEBUG_TRANS, "mux %p can read\n", m);

		set_bit(Rpending, &m->wsched);
@@ -617,17 +618,16 @@ static void p9_conn_create(struct p9_client *client) 


static void p9_poll_mux(struct p9_conn *m)

{

	int n;

	__poll_t n;

	int err = -ECONNRESET;



	if (m->err < 0)

		return;



	n = p9_fd_poll(m->client, NULL);

	if (n < 0 || n & (POLLERR | POLLHUP | POLLNVAL)) {

	n = p9_fd_poll(m->client, NULL, &err);

	if (n & (POLLERR | POLLHUP | POLLNVAL)) {

		p9_debug(P9_DEBUG_TRANS, "error mux %p err %d\n", m, n);

		if (n >= 0)

			n = -ECONNRESET;

		p9_conn_cancel(m, n);

		p9_conn_cancel(m, err);

	}



	if (n & POLLIN) {
@@ -663,7 +663,7 @@ static void p9_poll_mux(struct p9_conn *m) 


static int p9_fd_request(struct p9_client *client, struct p9_req_t *req)

{

	int n;

	__poll_t n;

	struct p9_trans_fd *ts = client->trans;

	struct p9_conn *m = &ts->conn;
@@ -680,7 +680,7 @@ static int p9_fd_request(struct p9_client *client, struct p9_req_t *req) 
	if (test_and_clear_bit(Wpending, &m->wsched))

		n = POLLOUT;

	else

		n = p9_fd_poll(m->client, NULL);

		n = p9_fd_poll(m->client, NULL, NULL);



	if (n & POLLOUT && !test_and_set_bit(Wworksched, &m->wsched))

		schedule_work(&m->wq);

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