[mirror_ubuntu-hirsute-kernel.git] / fs / smbfs / smbiod.c

/*
 *  smbiod.c
 *
 *  Copyright (C) 2000, Charles Loep / Corel Corp.
 *  Copyright (C) 2001, Urban Widmark
 */

#include <linux/config.h>

#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/file.h>
#include <linux/dcache.h>
#include <linux/smp_lock.h>
#include <linux/module.h>
#include <linux/net.h>
#include <linux/kthread.h>
#include <net/ip.h>

#include <linux/smb_fs.h>
#include <linux/smbno.h>
#include <linux/smb_mount.h>

#include <asm/system.h>
#include <asm/uaccess.h>

#include "smb_debug.h"
#include "request.h"
#include "proto.h"

enum smbiod_state {
	SMBIOD_DEAD,
	SMBIOD_STARTING,
	SMBIOD_RUNNING,
};

static enum smbiod_state smbiod_state = SMBIOD_DEAD;
static struct task_struct *smbiod_thread;
static DECLARE_WAIT_QUEUE_HEAD(smbiod_wait);
static LIST_HEAD(smb_servers);
static DEFINE_SPINLOCK(servers_lock);

#define SMBIOD_DATA_READY	(1<<0)
static long smbiod_flags;

static int smbiod(void *);
static int smbiod_start(void);

/*
 * called when there's work for us to do
 */
void smbiod_wake_up(void)
{
	if (smbiod_state == SMBIOD_DEAD)
		return;
	set_bit(SMBIOD_DATA_READY, &smbiod_flags);
	wake_up_interruptible(&smbiod_wait);
}

/*
 * start smbiod if none is running
 */
static int smbiod_start(void)
{
	struct task_struct *tsk;
	int err = 0;

	if (smbiod_state != SMBIOD_DEAD)
		return 0;
	smbiod_state = SMBIOD_STARTING;
	__module_get(THIS_MODULE);
	spin_unlock(&servers_lock);
	tsk = kthread_run(smbiod, NULL, "smbiod");
	if (IS_ERR(tsk)) {
		err = PTR_ERR(tsk);
		module_put(THIS_MODULE);
	}

	spin_lock(&servers_lock);
	if (err < 0) {
		smbiod_state = SMBIOD_DEAD;
		smbiod_thread = NULL;
	} else {
		smbiod_state = SMBIOD_RUNNING;
		smbiod_thread = tsk;
	}
	return err;
}

/*
 * register a server & start smbiod if necessary
 */
int smbiod_register_server(struct smb_sb_info *server)
{
	int ret;
	spin_lock(&servers_lock);
	list_add(&server->entry, &smb_servers);
	VERBOSE("%p\n", server);
	ret = smbiod_start();
	spin_unlock(&servers_lock);
	return ret;
}

/*
 * Unregister a server
 * Must be called with the server lock held.
 */
void smbiod_unregister_server(struct smb_sb_info *server)
{
	spin_lock(&servers_lock);
	list_del_init(&server->entry);
	VERBOSE("%p\n", server);
	spin_unlock(&servers_lock);

	smbiod_wake_up();
	smbiod_flush(server);
}

void smbiod_flush(struct smb_sb_info *server)
{
	struct list_head *tmp, *n;
	struct smb_request *req;

	list_for_each_safe(tmp, n, &server->xmitq) {
		req = list_entry(tmp, struct smb_request, rq_queue);
		req->rq_errno = -EIO;
		list_del_init(&req->rq_queue);
		smb_rput(req);
		wake_up_interruptible(&req->rq_wait);
	}
	list_for_each_safe(tmp, n, &server->recvq) {
		req = list_entry(tmp, struct smb_request, rq_queue);
		req->rq_errno = -EIO;
		list_del_init(&req->rq_queue);
		smb_rput(req);
		wake_up_interruptible(&req->rq_wait);
	}
}

/*
 * Wake up smbmount and make it reconnect to the server.
 * This must be called with the server locked.
 *
 * FIXME: add smbconnect version to this
 */
int smbiod_retry(struct smb_sb_info *server)
{
	struct list_head *head;
	struct smb_request *req;
	pid_t pid = server->conn_pid;
	int result = 0;

	VERBOSE("state: %d\n", server->state);
	if (server->state == CONN_VALID || server->state == CONN_RETRYING)
		goto out;

	smb_invalidate_inodes(server);

	/*
	 * Some requests are meaningless after a retry, so we abort them.
	 * One example are all requests using 'fileid' since the files are
	 * closed on retry.
	 */
	head = server->xmitq.next;
	while (head != &server->xmitq) {
		req = list_entry(head, struct smb_request, rq_queue);
		head = head->next;

		req->rq_bytes_sent = 0;
		if (req->rq_flags & SMB_REQ_NORETRY) {
			VERBOSE("aborting request %p on xmitq\n", req);
			req->rq_errno = -EIO;
			list_del_init(&req->rq_queue);
			smb_rput(req);
			wake_up_interruptible(&req->rq_wait);
		}
	}

	/*
	 * FIXME: test the code for retrying request we already sent
	 */
	head = server->recvq.next;
	while (head != &server->recvq) {
		req = list_entry(head, struct smb_request, rq_queue);
		head = head->next;
#if 0
		if (req->rq_flags & SMB_REQ_RETRY) {
			/* must move the request to the xmitq */
			VERBOSE("retrying request %p on recvq\n", req);
			list_del(&req->rq_queue);
			list_add(&req->rq_queue, &server->xmitq);
			continue;
		}
#endif

		VERBOSE("aborting request %p on recvq\n", req);
		/* req->rq_rcls = ???; */ /* FIXME: set smb error code too? */
		req->rq_errno = -EIO;
		list_del_init(&req->rq_queue);
		smb_rput(req);
		wake_up_interruptible(&req->rq_wait);
	}

	smb_close_socket(server);

	if (pid == 0) {
		/* FIXME: this is fatal, umount? */
		printk(KERN_ERR "smb_retry: no connection process\n");
		server->state = CONN_RETRIED;
		goto out;
	}

	/*
	 * Change state so that only one retry per server will be started.
	 */
	server->state = CONN_RETRYING;

	/*
	 * Note: use the "priv" flag, as a user process may need to reconnect.
	 */
	result = kill_proc(pid, SIGUSR1, 1);
	if (result) {
		/* FIXME: this is most likely fatal, umount? */
		printk(KERN_ERR "smb_retry: signal failed [%d]\n", result);
		goto out;
	}
	VERBOSE("signalled pid %d\n", pid);

	/* FIXME: The retried requests should perhaps get a "time boost". */

out:
	return result;
}

/*
 * Currently handles lockingX packets.
 */
static void smbiod_handle_request(struct smb_sb_info *server)
{
	PARANOIA("smbiod got a request ... and we don't implement oplocks!\n");
	server->rstate = SMB_RECV_DROP;
}

/*
 * Do some IO for one server.
 */
static void smbiod_doio(struct smb_sb_info *server)
{
	int result;
	int maxwork = 7;

	if (server->state != CONN_VALID)
		goto out;

	do {
		result = smb_request_recv(server);
		if (result < 0) {
			server->state = CONN_INVALID;
			smbiod_retry(server);
			goto out;	/* reconnecting is slow */
		} else if (server->rstate == SMB_RECV_REQUEST)
			smbiod_handle_request(server);
	} while (result > 0 && maxwork-- > 0);

	/*
	 * If there is more to read then we want to be sure to wake up again.
	 */
	if (server->state != CONN_VALID)
		goto out;
	if (smb_recv_available(server) > 0)
		set_bit(SMBIOD_DATA_READY, &smbiod_flags);

	do {
		result = smb_request_send_server(server);
		if (result < 0) {
			server->state = CONN_INVALID;
			smbiod_retry(server);
			goto out;	/* reconnecting is slow */
		}
	} while (result > 0);

	/*
	 * If the last request was not sent out we want to wake up again.
	 */
	if (!list_empty(&server->xmitq))
		set_bit(SMBIOD_DATA_READY, &smbiod_flags);

out:
	return;
}

/*
 * smbiod kernel thread
 */
static int smbiod(void *unused)
{
	allow_signal(SIGKILL);

	VERBOSE("SMB Kernel thread starting (%d) ...\n", current->pid);

	for (;;) {
		struct smb_sb_info *server;
		struct list_head *pos, *n;

		/* FIXME: Use poll? */
		wait_event_interruptible(smbiod_wait,
			 test_bit(SMBIOD_DATA_READY, &smbiod_flags));
		if (signal_pending(current)) {
			spin_lock(&servers_lock);
			smbiod_state = SMBIOD_DEAD;
			spin_unlock(&servers_lock);
			break;
		}

		clear_bit(SMBIOD_DATA_READY, &smbiod_flags);

		spin_lock(&servers_lock);
		if (list_empty(&smb_servers)) {
			smbiod_state = SMBIOD_DEAD;
			spin_unlock(&servers_lock);
			break;
		}

		list_for_each_safe(pos, n, &smb_servers) {
			server = list_entry(pos, struct smb_sb_info, entry);
			VERBOSE("checking server %p\n", server);

			if (server->state == CONN_VALID) {
				spin_unlock(&servers_lock);

				smb_lock_server(server);
				smbiod_doio(server);
				smb_unlock_server(server);

				spin_lock(&servers_lock);
			}
		}
		spin_unlock(&servers_lock);
	}

	VERBOSE("SMB Kernel thread exiting (%d) ...\n", current->pid);
	module_put_and_exit(0);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* smbiod.c
	3	*
	4	* Copyright (C) 2000, Charles Loep / Corel Corp.
	5	* Copyright (C) 2001, Urban Widmark
	6	*/
	7
	8	#include <linux/config.h>
	9
	10	#include <linux/sched.h>
	11	#include <linux/kernel.h>
	12	#include <linux/mm.h>
	13	#include <linux/string.h>
	14	#include <linux/stat.h>
	15	#include <linux/errno.h>
	16	#include <linux/slab.h>
	17	#include <linux/init.h>
	18	#include <linux/file.h>
	19	#include <linux/dcache.h>
	20	#include <linux/smp_lock.h>
	21	#include <linux/module.h>
	22	#include <linux/net.h>
fa366ad5	23	#include <linux/kthread.h>
1da177e4 LT	24	#include <net/ip.h>
	25
	26	#include <linux/smb_fs.h>
	27	#include <linux/smbno.h>
	28	#include <linux/smb_mount.h>
	29
	30	#include <asm/system.h>
	31	#include <asm/uaccess.h>
	32
	33	#include "smb_debug.h"
	34	#include "request.h"
	35	#include "proto.h"
	36
	37	enum smbiod_state {
	38	SMBIOD_DEAD,
	39	SMBIOD_STARTING,
	40	SMBIOD_RUNNING,
	41	};
	42
	43	static enum smbiod_state smbiod_state = SMBIOD_DEAD;
fa366ad5	44	static struct task_struct *smbiod_thread;
1da177e4 LT	45	static DECLARE_WAIT_QUEUE_HEAD(smbiod_wait);
	46	static LIST_HEAD(smb_servers);
	47	static DEFINE_SPINLOCK(servers_lock);
	48
	49	#define SMBIOD_DATA_READY (1<<0)
	50	static long smbiod_flags;
	51
	52	static int smbiod(void *);
	53	static int smbiod_start(void);
	54
	55	/*
	56	* called when there's work for us to do
	57	*/
	58	void smbiod_wake_up(void)
	59	{
	60	if (smbiod_state == SMBIOD_DEAD)
	61	return;
	62	set_bit(SMBIOD_DATA_READY, &smbiod_flags);
	63	wake_up_interruptible(&smbiod_wait);
	64	}
	65
	66	/*
	67	* start smbiod if none is running
	68	*/
	69	static int smbiod_start(void)
	70	{
fa366ad5 SH	71	struct task_struct *tsk;
	72	int err = 0;
	73
1da177e4 LT	74	if (smbiod_state != SMBIOD_DEAD)
	75	return 0;
	76	smbiod_state = SMBIOD_STARTING;
	77	__module_get(THIS_MODULE);
	78	spin_unlock(&servers_lock);
fa366ad5 SH	79	tsk = kthread_run(smbiod, NULL, "smbiod");
	80	if (IS_ERR(tsk)) {
	81	err = PTR_ERR(tsk);
1da177e4	82	module_put(THIS_MODULE);
fa366ad5	83	}
1da177e4 LT	84
1da177e4 LT	85	spin_lock(&servers_lock);
fa366ad5 SH	86	if (err < 0) {
	87	smbiod_state = SMBIOD_DEAD;
	88	smbiod_thread = NULL;
	89	} else {
	90	smbiod_state = SMBIOD_RUNNING;
	91	smbiod_thread = tsk;
	92	}
	93	return err;
1da177e4 LT	94	}
	95
	96	/*
	97	* register a server & start smbiod if necessary
	98	*/
	99	int smbiod_register_server(struct smb_sb_info *server)
	100	{
	101	int ret;
	102	spin_lock(&servers_lock);
	103	list_add(&server->entry, &smb_servers);
	104	VERBOSE("%p\n", server);
	105	ret = smbiod_start();
	106	spin_unlock(&servers_lock);
	107	return ret;
	108	}
	109
	110	/*
	111	* Unregister a server
	112	* Must be called with the server lock held.
	113	*/
	114	void smbiod_unregister_server(struct smb_sb_info *server)
	115	{
	116	spin_lock(&servers_lock);
	117	list_del_init(&server->entry);
	118	VERBOSE("%p\n", server);
	119	spin_unlock(&servers_lock);
	120
	121	smbiod_wake_up();
	122	smbiod_flush(server);
	123	}
	124
	125	void smbiod_flush(struct smb_sb_info *server)
	126	{
	127	struct list_head tmp, n;
	128	struct smb_request *req;
	129
	130	list_for_each_safe(tmp, n, &server->xmitq) {
	131	req = list_entry(tmp, struct smb_request, rq_queue);
	132	req->rq_errno = -EIO;
	133	list_del_init(&req->rq_queue);
	134	smb_rput(req);
	135	wake_up_interruptible(&req->rq_wait);
	136	}
	137	list_for_each_safe(tmp, n, &server->recvq) {
	138	req = list_entry(tmp, struct smb_request, rq_queue);
	139	req->rq_errno = -EIO;
	140	list_del_init(&req->rq_queue);
	141	smb_rput(req);
	142	wake_up_interruptible(&req->rq_wait);
	143	}
	144	}
	145
	146	/*
	147	* Wake up smbmount and make it reconnect to the server.
	148	* This must be called with the server locked.
	149	*
	150	* FIXME: add smbconnect version to this
	151	*/
	152	int smbiod_retry(struct smb_sb_info *server)
	153	{
	154	struct list_head *head;
	155	struct smb_request *req;
	156	pid_t pid = server->conn_pid;
	157	int result = 0;
158
159	VERBOSE("state: %d\n", server->state);
160	if (server->state == CONN_VALID \|\| server->state == CONN_RETRYING)
161	goto out;
162
163	smb_invalidate_inodes(server);
164
165	/*
166	* Some requests are meaningless after a retry, so we abort them.
167	* One example are all requests using 'fileid' since the files are
168	* closed on retry.
169	*/
170	head = server->xmitq.next;
171	while (head != &server->xmitq) {
172	req = list_entry(head, struct smb_request, rq_queue);
173	head = head->next;
174
175	req->rq_bytes_sent = 0;
176	if (req->rq_flags & SMB_REQ_NORETRY) {
177	VERBOSE("aborting request %p on xmitq\n", req);
178	req->rq_errno = -EIO;
179	list_del_init(&req->rq_queue);
180	smb_rput(req);
181	wake_up_interruptible(&req->rq_wait);
182	}
183	}
184
185	/*
186	* FIXME: test the code for retrying request we already sent
187	*/
188	head = server->recvq.next;
189	while (head != &server->recvq) {
190	req = list_entry(head, struct smb_request, rq_queue);
191	head = head->next;
192	#if 0
193	if (req->rq_flags & SMB_REQ_RETRY) {
194	/* must move the request to the xmitq */
195	VERBOSE("retrying request %p on recvq\n", req);
196	list_del(&req->rq_queue);
197	list_add(&req->rq_queue, &server->xmitq);
198	continue;
199	}
200	#endif
201
202	VERBOSE("aborting request %p on recvq\n", req);
203	/* req->rq_rcls = ???; / / FIXME: set smb error code too? */
204	req->rq_errno = -EIO;
205	list_del_init(&req->rq_queue);
206	smb_rput(req);
207	wake_up_interruptible(&req->rq_wait);
208	}
209
210	smb_close_socket(server);
211
212	if (pid == 0) {
213	/* FIXME: this is fatal, umount? */
214	printk(KERN_ERR "smb_retry: no connection process\n");
215	server->state = CONN_RETRIED;
216	goto out;
217	}
218
219	/*
220	* Change state so that only one retry per server will be started.
221	*/
222	server->state = CONN_RETRYING;
223
224	/*
225	* Note: use the "priv" flag, as a user process may need to reconnect.
226	*/
227	result = kill_proc(pid, SIGUSR1, 1);
228	if (result) {
229	/* FIXME: this is most likely fatal, umount? */
230	printk(KERN_ERR "smb_retry: signal failed [%d]\n", result);
231	goto out;
232	}
233	VERBOSE("signalled pid %d\n", pid);
234
235	/* FIXME: The retried requests should perhaps get a "time boost". */
236
237	out:
238	return result;
239	}
240
241	/*
242	* Currently handles lockingX packets.
243	*/
244	static void smbiod_handle_request(struct smb_sb_info *server)
245	{
246	PARANOIA("smbiod got a request ... and we don't implement oplocks!\n");
247	server->rstate = SMB_RECV_DROP;
248	}
249
250	/*
251	* Do some IO for one server.
252	*/
253	static void smbiod_doio(struct smb_sb_info *server)
254	{
255	int result;
256	int maxwork = 7;
257
258	if (server->state != CONN_VALID)
259	goto out;
260
261	do {
262	result = smb_request_recv(server);
263	if (result < 0) {
264	server->state = CONN_INVALID;
265	smbiod_retry(server);
266	goto out; /* reconnecting is slow */
267	} else if (server->rstate == SMB_RECV_REQUEST)
268	smbiod_handle_request(server);
269	} while (result > 0 && maxwork-- > 0);
270
271	/*
272	* If there is more to read then we want to be sure to wake up again.
273	*/
274	if (server->state != CONN_VALID)
275	goto out;
276	if (smb_recv_available(server) > 0)
277	set_bit(SMBIOD_DATA_READY, &smbiod_flags);
278
279	do {
280	result = smb_request_send_server(server);
281	if (result < 0) {
282	server->state = CONN_INVALID;
283	smbiod_retry(server);
284	goto out; /* reconnecting is slow */
285	}
286	} while (result > 0);
287
288	/*
289	* If the last request was not sent out we want to wake up again.
290	*/
291	if (!list_empty(&server->xmitq))
292	set_bit(SMBIOD_DATA_READY, &smbiod_flags);
293
294	out:
295	return;
296	}
297
298	/*
299	* smbiod kernel thread
300	*/
301	static int smbiod(void *unused)
302	{
1da177e4 LT	303	allow_signal(SIGKILL);
	304
	305	VERBOSE("SMB Kernel thread starting (%d) ...\n", current->pid);
	306
	307	for (;;) {
	308	struct smb_sb_info *server;
	309	struct list_head pos, n;
	310
	311	/* FIXME: Use poll? */
	312	wait_event_interruptible(smbiod_wait,
	313	test_bit(SMBIOD_DATA_READY, &smbiod_flags));
	314	if (signal_pending(current)) {
	315	spin_lock(&servers_lock);
	316	smbiod_state = SMBIOD_DEAD;
	317	spin_unlock(&servers_lock);
	318	break;
	319	}
	320
	321	clear_bit(SMBIOD_DATA_READY, &smbiod_flags);
	322
	323	spin_lock(&servers_lock);
	324	if (list_empty(&smb_servers)) {
	325	smbiod_state = SMBIOD_DEAD;
	326	spin_unlock(&servers_lock);
	327	break;
	328	}
	329
	330	list_for_each_safe(pos, n, &smb_servers) {
	331	server = list_entry(pos, struct smb_sb_info, entry);
	332	VERBOSE("checking server %p\n", server);
	333
	334	if (server->state == CONN_VALID) {
	335	spin_unlock(&servers_lock);
	336
	337	smb_lock_server(server);
	338	smbiod_doio(server);
	339	smb_unlock_server(server);
	340
	341	spin_lock(&servers_lock);
	342	}
	343	}
	344	spin_unlock(&servers_lock);
	345	}
	346
	347	VERBOSE("SMB Kernel thread exiting (%d) ...\n", current->pid);
	348	module_put_and_exit(0);
	349	}