[linux.git] / fs / smbfs / smbiod.c

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


#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/init.h>
#include <linux/file.h>
#include <linux/dcache.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 unsigned 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;
	struct pid *pid = get_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_move(&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) {
		/* 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_pid(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_nr(pid));

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

out:
	put_pid(pid);
	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)
{
	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
1da177e4 LT	8
	9	#include <linux/sched.h>
	10	#include <linux/kernel.h>
	11	#include <linux/mm.h>
	12	#include <linux/string.h>
	13	#include <linux/stat.h>
	14	#include <linux/errno.h>
1da177e4 LT	15	#include <linux/init.h>
	16	#include <linux/file.h>
	17	#include <linux/dcache.h>
1da177e4 LT	18	#include <linux/module.h>
1da177e4 LT	19	#include <linux/net.h>
fa366ad5	20	#include <linux/kthread.h>
1da177e4 LT	21	#include <net/ip.h>
	22
	23	#include <linux/smb_fs.h>
	24	#include <linux/smbno.h>
	25	#include <linux/smb_mount.h>
	26
	27	#include <asm/system.h>
	28	#include <asm/uaccess.h>
	29
	30	#include "smb_debug.h"
	31	#include "request.h"
	32	#include "proto.h"
	33
	34	enum smbiod_state {
	35	SMBIOD_DEAD,
	36	SMBIOD_STARTING,
	37	SMBIOD_RUNNING,
	38	};
	39
	40	static enum smbiod_state smbiod_state = SMBIOD_DEAD;
fa366ad5	41	static struct task_struct *smbiod_thread;
1da177e4 LT	42	static DECLARE_WAIT_QUEUE_HEAD(smbiod_wait);
	43	static LIST_HEAD(smb_servers);
	44	static DEFINE_SPINLOCK(servers_lock);
	45
	46	#define SMBIOD_DATA_READY (1<<0)
5ba25331	47	static unsigned long smbiod_flags;
1da177e4 LT	48
	49	static int smbiod(void *);
	50	static int smbiod_start(void);
	51
	52	/*
	53	* called when there's work for us to do
	54	*/
	55	void smbiod_wake_up(void)
	56	{
	57	if (smbiod_state == SMBIOD_DEAD)
	58	return;
	59	set_bit(SMBIOD_DATA_READY, &smbiod_flags);
	60	wake_up_interruptible(&smbiod_wait);
	61	}
	62
	63	/*
	64	* start smbiod if none is running
	65	*/
	66	static int smbiod_start(void)
	67	{
fa366ad5 SH	68	struct task_struct *tsk;
	69	int err = 0;
	70
1da177e4 LT	71	if (smbiod_state != SMBIOD_DEAD)
	72	return 0;
	73	smbiod_state = SMBIOD_STARTING;
	74	__module_get(THIS_MODULE);
	75	spin_unlock(&servers_lock);
fa366ad5 SH	76	tsk = kthread_run(smbiod, NULL, "smbiod");
	77	if (IS_ERR(tsk)) {
	78	err = PTR_ERR(tsk);
1da177e4	79	module_put(THIS_MODULE);
fa366ad5	80	}
1da177e4 LT	81
1da177e4 LT	82	spin_lock(&servers_lock);
fa366ad5 SH	83	if (err < 0) {
	84	smbiod_state = SMBIOD_DEAD;
	85	smbiod_thread = NULL;
	86	} else {
	87	smbiod_state = SMBIOD_RUNNING;
	88	smbiod_thread = tsk;
	89	}
	90	return err;
1da177e4 LT	91	}
	92
	93	/*
	94	* register a server & start smbiod if necessary
	95	*/
	96	int smbiod_register_server(struct smb_sb_info *server)
	97	{
	98	int ret;
	99	spin_lock(&servers_lock);
	100	list_add(&server->entry, &smb_servers);
	101	VERBOSE("%p\n", server);
	102	ret = smbiod_start();
	103	spin_unlock(&servers_lock);
	104	return ret;
	105	}
	106
	107	/*
	108	* Unregister a server
	109	* Must be called with the server lock held.
	110	*/
	111	void smbiod_unregister_server(struct smb_sb_info *server)
	112	{
	113	spin_lock(&servers_lock);
	114	list_del_init(&server->entry);
	115	VERBOSE("%p\n", server);
	116	spin_unlock(&servers_lock);
	117
	118	smbiod_wake_up();
	119	smbiod_flush(server);
	120	}
	121
	122	void smbiod_flush(struct smb_sb_info *server)
	123	{
	124	struct list_head tmp, n;
	125	struct smb_request *req;
	126
	127	list_for_each_safe(tmp, n, &server->xmitq) {
	128	req = list_entry(tmp, struct smb_request, rq_queue);
	129	req->rq_errno = -EIO;
	130	list_del_init(&req->rq_queue);
	131	smb_rput(req);
	132	wake_up_interruptible(&req->rq_wait);
	133	}
	134	list_for_each_safe(tmp, n, &server->recvq) {
	135	req = list_entry(tmp, struct smb_request, rq_queue);
	136	req->rq_errno = -EIO;
	137	list_del_init(&req->rq_queue);
	138	smb_rput(req);
	139	wake_up_interruptible(&req->rq_wait);
	140	}
	141	}
	142
	143	/*
	144	* Wake up smbmount and make it reconnect to the server.
	145	* This must be called with the server locked.
	146	*
	147	* FIXME: add smbconnect version to this
	148	*/
	149	int smbiod_retry(struct smb_sb_info *server)
	150	{
	151	struct list_head *head;
	152	struct smb_request *req;
a71113da	153	struct pid *pid = get_pid(server->conn_pid);
1da177e4 LT	154	int result = 0;
	155
	156	VERBOSE("state: %d\n", server->state);
	157	if (server->state == CONN_VALID \|\| server->state == CONN_RETRYING)
	158	goto out;
	159
	160	smb_invalidate_inodes(server);
	161
	162	/*
	163	* Some requests are meaningless after a retry, so we abort them.
	164	* One example are all requests using 'fileid' since the files are
	165	* closed on retry.
	166	*/
	167	head = server->xmitq.next;
	168	while (head != &server->xmitq) {
	169	req = list_entry(head, struct smb_request, rq_queue);
	170	head = head->next;
	171
	172	req->rq_bytes_sent = 0;
	173	if (req->rq_flags & SMB_REQ_NORETRY) {
	174	VERBOSE("aborting request %p on xmitq\n", req);
	175	req->rq_errno = -EIO;
	176	list_del_init(&req->rq_queue);
	177	smb_rput(req);
	178	wake_up_interruptible(&req->rq_wait);
	179	}
	180	}
	181
	182	/*
	183	* FIXME: test the code for retrying request we already sent
	184	*/
	185	head = server->recvq.next;
	186	while (head != &server->recvq) {
	187	req = list_entry(head, struct smb_request, rq_queue);
	188	head = head->next;
	189	#if 0
	190	if (req->rq_flags & SMB_REQ_RETRY) {
	191	/* must move the request to the xmitq */
	192	VERBOSE("retrying request %p on recvq\n", req);
f116629d	193	list_move(&req->rq_queue, &server->xmitq);
1da177e4 LT	194	continue;
	195	}
	196	#endif
	197
	198	VERBOSE("aborting request %p on recvq\n", req);
	199	/* req->rq_rcls = ???; / / FIXME: set smb error code too? */
	200	req->rq_errno = -EIO;
	201	list_del_init(&req->rq_queue);
	202	smb_rput(req);
	203	wake_up_interruptible(&req->rq_wait);
	204	}
	205
	206	smb_close_socket(server);
	207
9dce07f1	208	if (!pid) {
1da177e4 LT	209	/* FIXME: this is fatal, umount? */
	210	printk(KERN_ERR "smb_retry: no connection process\n");
	211	server->state = CONN_RETRIED;
	212	goto out;
	213	}
	214
	215	/*
	216	* Change state so that only one retry per server will be started.
	217	*/
	218	server->state = CONN_RETRYING;
	219
	220	/*
	221	* Note: use the "priv" flag, as a user process may need to reconnect.
	222	*/
a71113da	223	result = kill_pid(pid, SIGUSR1, 1);
1da177e4 LT	224	if (result) {
	225	/* FIXME: this is most likely fatal, umount? */
	226	printk(KERN_ERR "smb_retry: signal failed [%d]\n", result);
	227	goto out;
	228	}
dbaf4c02	229	VERBOSE("signalled pid %d\n", pid_nr(pid));
1da177e4 LT	230
	231	/* FIXME: The retried requests should perhaps get a "time boost". */
	232
	233	out:
a71113da	234	put_pid(pid);
1da177e4 LT	235	return result;
	236	}
	237
	238	/*
	239	* Currently handles lockingX packets.
	240	*/
	241	static void smbiod_handle_request(struct smb_sb_info *server)
	242	{
	243	PARANOIA("smbiod got a request ... and we don't implement oplocks!\n");
	244	server->rstate = SMB_RECV_DROP;
	245	}
	246
	247	/*
	248	* Do some IO for one server.
	249	*/
	250	static void smbiod_doio(struct smb_sb_info *server)
	251	{
	252	int result;
	253	int maxwork = 7;
	254
	255	if (server->state != CONN_VALID)
	256	goto out;
	257
	258	do {
	259	result = smb_request_recv(server);
	260	if (result < 0) {
	261	server->state = CONN_INVALID;
	262	smbiod_retry(server);
	263	goto out; /* reconnecting is slow */
	264	} else if (server->rstate == SMB_RECV_REQUEST)
	265	smbiod_handle_request(server);
	266	} while (result > 0 && maxwork-- > 0);
	267
	268	/*
	269	* If there is more to read then we want to be sure to wake up again.
	270	*/
	271	if (server->state != CONN_VALID)
	272	goto out;
	273	if (smb_recv_available(server) > 0)
	274	set_bit(SMBIOD_DATA_READY, &smbiod_flags);
	275
	276	do {
	277	result = smb_request_send_server(server);
	278	if (result < 0) {
	279	server->state = CONN_INVALID;
	280	smbiod_retry(server);
	281	goto out; /* reconnecting is slow */
	282	}
	283	} while (result > 0);
	284
	285	/*
	286	* If the last request was not sent out we want to wake up again.
	287	*/
	288	if (!list_empty(&server->xmitq))
	289	set_bit(SMBIOD_DATA_READY, &smbiod_flags);
	290
	291	out:
	292	return;
	293	}
	294
	295	/*
	296	* smbiod kernel thread
	297	*/
	298	static int smbiod(void *unused)
299	{
1da177e4 LT	300	VERBOSE("SMB Kernel thread starting (%d) ...\n", current->pid);
	301
	302	for (;;) {
	303	struct smb_sb_info *server;
	304	struct list_head pos, n;
	305
	306	/* FIXME: Use poll? */
	307	wait_event_interruptible(smbiod_wait,
	308	test_bit(SMBIOD_DATA_READY, &smbiod_flags));
	309	if (signal_pending(current)) {
	310	spin_lock(&servers_lock);
	311	smbiod_state = SMBIOD_DEAD;
	312	spin_unlock(&servers_lock);
	313	break;
	314	}
	315
	316	clear_bit(SMBIOD_DATA_READY, &smbiod_flags);
	317
	318	spin_lock(&servers_lock);
	319	if (list_empty(&smb_servers)) {
	320	smbiod_state = SMBIOD_DEAD;
	321	spin_unlock(&servers_lock);
	322	break;
	323	}
	324
	325	list_for_each_safe(pos, n, &smb_servers) {
	326	server = list_entry(pos, struct smb_sb_info, entry);
	327	VERBOSE("checking server %p\n", server);
	328
	329	if (server->state == CONN_VALID) {
	330	spin_unlock(&servers_lock);
	331
	332	smb_lock_server(server);
	333	smbiod_doio(server);
	334	smb_unlock_server(server);
	335
	336	spin_lock(&servers_lock);
	337	}
	338	}
	339	spin_unlock(&servers_lock);
	340	}
	341
	342	VERBOSE("SMB Kernel thread exiting (%d) ...\n", current->pid);
	343	module_put_and_exit(0);
	344	}