[linux-2.6-block.git] / fs / coda / psdev.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *      	An implementation of a loadable kernel mode driver providing
 *		multiple kernel/user space bidirectional communications links.
 *
 * 		Author: 	Alan Cox <alan@lxorguk.ukuu.org.uk>
 * 
 *              Adapted to become the Linux 2.0 Coda pseudo device
 *              Peter  Braam  <braam@maths.ox.ac.uk> 
 *              Michael Callahan <mjc@emmy.smith.edu>           
 *
 *              Changes for Linux 2.1
 *              Copyright (c) 1997 Carnegie-Mellon University
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/major.h>
#include <linux/time.h>
#include <linux/sched/signal.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/fcntl.h>
#include <linux/delay.h>
#include <linux/skbuff.h>
#include <linux/proc_fs.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/device.h>
#include <linux/pid_namespace.h>
#include <asm/io.h>
#include <linux/uaccess.h>

#include <linux/coda.h>
#include "coda_psdev.h"
#include "coda_linux.h"

#include "coda_int.h"

/* statistics */
int           coda_hard;         /* allows signals during upcalls */
unsigned long coda_timeout = 30; /* .. secs, then signals will dequeue */


struct venus_comm coda_comms[MAX_CODADEVS];
static struct class *coda_psdev_class;

/*
 * Device operations
 */

static __poll_t coda_psdev_poll(struct file *file, poll_table * wait)
{
        struct venus_comm *vcp = (struct venus_comm *) file->private_data;
	__poll_t mask = EPOLLOUT | EPOLLWRNORM;

	poll_wait(file, &vcp->vc_waitq, wait);
	mutex_lock(&vcp->vc_mutex);
	if (!list_empty(&vcp->vc_pending))
                mask |= EPOLLIN | EPOLLRDNORM;
	mutex_unlock(&vcp->vc_mutex);

	return mask;
}

static long coda_psdev_ioctl(struct file * filp, unsigned int cmd, unsigned long arg)
{
	unsigned int data;

	switch(cmd) {
	case CIOC_KERNEL_VERSION:
		data = CODA_KERNEL_VERSION;
		return put_user(data, (int __user *) arg);
	default:
		return -ENOTTY;
	}

	return 0;
}

/*
 *	Receive a message written by Venus to the psdev
 */
 
static ssize_t coda_psdev_write(struct file *file, const char __user *buf, 
				size_t nbytes, loff_t *off)
{
        struct venus_comm *vcp = (struct venus_comm *) file->private_data;
        struct upc_req *req = NULL;
        struct upc_req *tmp;
	struct list_head *lh;
	struct coda_in_hdr hdr;
	ssize_t retval = 0, count = 0;
	int error;

	/* make sure there is enough to copy out the (opcode, unique) values */
	if (nbytes < (2 * sizeof(u_int32_t)))
		return -EINVAL;

        /* Peek at the opcode, uniquefier */
	if (copy_from_user(&hdr, buf, 2 * sizeof(u_int32_t)))
	        return -EFAULT;

        if (DOWNCALL(hdr.opcode)) {
		union outputArgs *dcbuf;
		int size = sizeof(*dcbuf);

		if  ( nbytes < sizeof(struct coda_out_hdr) ) {
			pr_warn("coda_downcall opc %d uniq %d, not enough!\n",
				hdr.opcode, hdr.unique);
			count = nbytes;
			goto out;
		}
		if ( nbytes > size ) {
			pr_warn("downcall opc %d, uniq %d, too much!",
				hdr.opcode, hdr.unique);
		        nbytes = size;
		}
		dcbuf = kvmalloc(nbytes, GFP_KERNEL);
		if (!dcbuf) {
			retval = -ENOMEM;
			goto out;
		}
		if (copy_from_user(dcbuf, buf, nbytes)) {
			kvfree(dcbuf);
			retval = -EFAULT;
			goto out;
		}

		/* what downcall errors does Venus handle ? */
		error = coda_downcall(vcp, hdr.opcode, dcbuf, nbytes);

		kvfree(dcbuf);
		if (error) {
			pr_warn("%s: coda_downcall error: %d\n",
				__func__, error);
			retval = error;
			goto out;
		}
		count = nbytes;
		goto out;
	}
        
	/* Look for the message on the processing queue. */
	mutex_lock(&vcp->vc_mutex);
	list_for_each(lh, &vcp->vc_processing) {
		tmp = list_entry(lh, struct upc_req , uc_chain);
		if (tmp->uc_unique == hdr.unique) {
			req = tmp;
			list_del(&req->uc_chain);
			break;
		}
	}
	mutex_unlock(&vcp->vc_mutex);

	if (!req) {
		pr_warn("%s: msg (%d, %d) not found\n",
			__func__, hdr.opcode, hdr.unique);
		retval = -ESRCH;
		goto out;
	}

        /* move data into response buffer. */
	if (req->uc_outSize < nbytes) {
		pr_warn("%s: too much cnt: %d, cnt: %ld, opc: %d, uniq: %d.\n",
			__func__, req->uc_outSize, (long)nbytes,
			hdr.opcode, hdr.unique);
		nbytes = req->uc_outSize; /* don't have more space! */
	}
        if (copy_from_user(req->uc_data, buf, nbytes)) {
		req->uc_flags |= CODA_REQ_ABORT;
		wake_up(&req->uc_sleep);
		retval = -EFAULT;
		goto out;
	}

	/* adjust outsize. is this useful ?? */
	req->uc_outSize = nbytes;
	req->uc_flags |= CODA_REQ_WRITE;
	count = nbytes;

	/* Convert filedescriptor into a file handle */
	if (req->uc_opcode == CODA_OPEN_BY_FD) {
		struct coda_open_by_fd_out *outp =
			(struct coda_open_by_fd_out *)req->uc_data;
		if (!outp->oh.result) {
			outp->fh = fget(outp->fd);
			if (!outp->fh)
				return -EBADF;
		}
	}

        wake_up(&req->uc_sleep);
out:
        return(count ? count : retval);  
}

/*
 *	Read a message from the kernel to Venus
 */

static ssize_t coda_psdev_read(struct file * file, char __user * buf, 
			       size_t nbytes, loff_t *off)
{
	DECLARE_WAITQUEUE(wait, current);
        struct venus_comm *vcp = (struct venus_comm *) file->private_data;
        struct upc_req *req;
	ssize_t retval = 0, count = 0;

	if (nbytes == 0)
		return 0;

	mutex_lock(&vcp->vc_mutex);

	add_wait_queue(&vcp->vc_waitq, &wait);
	set_current_state(TASK_INTERRUPTIBLE);

	while (list_empty(&vcp->vc_pending)) {
		if (file->f_flags & O_NONBLOCK) {
			retval = -EAGAIN;
			break;
		}
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		mutex_unlock(&vcp->vc_mutex);
		schedule();
		mutex_lock(&vcp->vc_mutex);
	}

	set_current_state(TASK_RUNNING);
	remove_wait_queue(&vcp->vc_waitq, &wait);

	if (retval)
		goto out;

	req = list_entry(vcp->vc_pending.next, struct upc_req,uc_chain);
	list_del(&req->uc_chain);

	/* Move the input args into userspace */
	count = req->uc_inSize;
	if (nbytes < req->uc_inSize) {
		pr_warn("%s: Venus read %ld bytes of %d in message\n",
			__func__, (long)nbytes, req->uc_inSize);
		count = nbytes;
        }

	if (copy_to_user(buf, req->uc_data, count))
	        retval = -EFAULT;
        
	/* If request was not a signal, enqueue and don't free */
	if (!(req->uc_flags & CODA_REQ_ASYNC)) {
		req->uc_flags |= CODA_REQ_READ;
		list_add_tail(&(req->uc_chain), &vcp->vc_processing);
		goto out;
	}

	kvfree(req->uc_data);
	kfree(req);
out:
	mutex_unlock(&vcp->vc_mutex);
	return (count ? count : retval);
}

static int coda_psdev_open(struct inode * inode, struct file * file)
{
	struct venus_comm *vcp;
	int idx, err;

	if (task_active_pid_ns(current) != &init_pid_ns)
		return -EINVAL;

	if (current_user_ns() != &init_user_ns)
		return -EINVAL;

	idx = iminor(inode);
	if (idx < 0 || idx >= MAX_CODADEVS)
		return -ENODEV;

	err = -EBUSY;
	vcp = &coda_comms[idx];
	mutex_lock(&vcp->vc_mutex);

	if (!vcp->vc_inuse) {
		vcp->vc_inuse++;

		INIT_LIST_HEAD(&vcp->vc_pending);
		INIT_LIST_HEAD(&vcp->vc_processing);
		init_waitqueue_head(&vcp->vc_waitq);
		vcp->vc_sb = NULL;
		vcp->vc_seq = 0;

		file->private_data = vcp;
		err = 0;
	}

	mutex_unlock(&vcp->vc_mutex);
	return err;
}


static int coda_psdev_release(struct inode * inode, struct file * file)
{
	struct venus_comm *vcp = (struct venus_comm *) file->private_data;
	struct upc_req *req, *tmp;

	if (!vcp || !vcp->vc_inuse ) {
		pr_warn("%s: Not open.\n", __func__);
		return -1;
	}

	mutex_lock(&vcp->vc_mutex);

	/* Wakeup clients so they can return. */
	list_for_each_entry_safe(req, tmp, &vcp->vc_pending, uc_chain) {
		list_del(&req->uc_chain);

		/* Async requests need to be freed here */
		if (req->uc_flags & CODA_REQ_ASYNC) {
			kvfree(req->uc_data);
			kfree(req);
			continue;
		}
		req->uc_flags |= CODA_REQ_ABORT;
		wake_up(&req->uc_sleep);
	}

	list_for_each_entry_safe(req, tmp, &vcp->vc_processing, uc_chain) {
		list_del(&req->uc_chain);

		req->uc_flags |= CODA_REQ_ABORT;
		wake_up(&req->uc_sleep);
	}

	file->private_data = NULL;
	vcp->vc_inuse--;
	mutex_unlock(&vcp->vc_mutex);
	return 0;
}


static const struct file_operations coda_psdev_fops = {
	.owner		= THIS_MODULE,
	.read		= coda_psdev_read,
	.write		= coda_psdev_write,
	.poll		= coda_psdev_poll,
	.unlocked_ioctl	= coda_psdev_ioctl,
	.open		= coda_psdev_open,
	.release	= coda_psdev_release,
	.llseek		= noop_llseek,
};

static int __init init_coda_psdev(void)
{
	int i, err = 0;
	if (register_chrdev(CODA_PSDEV_MAJOR, "coda", &coda_psdev_fops)) {
		pr_err("%s: unable to get major %d\n",
		       __func__, CODA_PSDEV_MAJOR);
		return -EIO;
	}
	coda_psdev_class = class_create(THIS_MODULE, "coda");
	if (IS_ERR(coda_psdev_class)) {
		err = PTR_ERR(coda_psdev_class);
		goto out_chrdev;
	}		
	for (i = 0; i < MAX_CODADEVS; i++) {
		mutex_init(&(&coda_comms[i])->vc_mutex);
		device_create(coda_psdev_class, NULL,
			      MKDEV(CODA_PSDEV_MAJOR, i), NULL, "cfs%d", i);
	}
	coda_sysctl_init();
	goto out;

out_chrdev:
	unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
out:
	return err;
}

MODULE_AUTHOR("Jan Harkes, Peter J. Braam");
MODULE_DESCRIPTION("Coda Distributed File System VFS interface");
MODULE_ALIAS_CHARDEV_MAJOR(CODA_PSDEV_MAJOR);
MODULE_LICENSE("GPL");
MODULE_VERSION("7.0");

static int __init init_coda(void)
{
	int status;
	int i;

	status = coda_init_inodecache();
	if (status)
		goto out2;
	status = init_coda_psdev();
	if ( status ) {
		pr_warn("Problem (%d) in init_coda_psdev\n", status);
		goto out1;
	}
	
	status = register_filesystem(&coda_fs_type);
	if (status) {
		pr_warn("failed to register filesystem!\n");
		goto out;
	}
	return 0;
out:
	for (i = 0; i < MAX_CODADEVS; i++)
		device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
	class_destroy(coda_psdev_class);
	unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
	coda_sysctl_clean();
out1:
	coda_destroy_inodecache();
out2:
	return status;
}

static void __exit exit_coda(void)
{
        int err, i;

	err = unregister_filesystem(&coda_fs_type);
	if (err != 0)
		pr_warn("failed to unregister filesystem\n");
	for (i = 0; i < MAX_CODADEVS; i++)
		device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
	class_destroy(coda_psdev_class);
	unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
	coda_sysctl_clean();
	coda_destroy_inodecache();
}

module_init(init_coda);
module_exit(exit_coda);
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4 LT	2	/*
	3	* An implementation of a loadable kernel mode driver providing
	4	* multiple kernel/user space bidirectional communications links.
	5	*
526719ba	6	* Author: Alan Cox <alan@lxorguk.ukuu.org.uk>
1da177e4 LT	7	*
	8	* Adapted to become the Linux 2.0 Coda pseudo device
	9	* Peter Braam <braam@maths.ox.ac.uk>
	10	* Michael Callahan <mjc@emmy.smith.edu>
	11	*
	12	* Changes for Linux 2.1
	13	* Copyright (c) 1997 Carnegie-Mellon University
	14	*/
	15
	16	#include <linux/module.h>
	17	#include <linux/errno.h>
	18	#include <linux/kernel.h>
	19	#include <linux/major.h>
	20	#include <linux/time.h>
174cd4b1	21	#include <linux/sched/signal.h>
1da177e4 LT	22	#include <linux/slab.h>
	23	#include <linux/ioport.h>
	24	#include <linux/fcntl.h>
	25	#include <linux/delay.h>
	26	#include <linux/skbuff.h>
	27	#include <linux/proc_fs.h>
1da177e4 LT	28	#include <linux/vmalloc.h>
	29	#include <linux/fs.h>
	30	#include <linux/file.h>
	31	#include <linux/poll.h>
	32	#include <linux/init.h>
	33	#include <linux/list.h>
da47c19e	34	#include <linux/mutex.h>
1da177e4	35	#include <linux/device.h>
9fd973e0	36	#include <linux/pid_namespace.h>
1da177e4	37	#include <asm/io.h>
834b46c3	38	#include <linux/uaccess.h>
1da177e4 LT	39
1da177e4 LT	40	#include <linux/coda.h>
8fc8b9df	41	#include "coda_psdev.h"
31a203df AV	42	#include "coda_linux.h"
31a203df AV	43
c98d8cfb	44	#include "coda_int.h"
1da177e4	45
1da177e4 LT	46	/* statistics */
	47	int coda_hard; /* allows signals during upcalls */
	48	unsigned long coda_timeout = 30; /* .. secs, then signals will dequeue */
	49
	50
	51	struct venus_comm coda_comms[MAX_CODADEVS];
1db560af	52	static struct class *coda_psdev_class;
1da177e4 LT	53
	54	/*
	55	* Device operations
	56	*/
	57
076ccb76	58	static __poll_t coda_psdev_poll(struct file file, poll_table wait)
1da177e4 LT	59	{
1da177e4 LT	60	struct venus_comm vcp = (struct venus_comm ) file->private_data;
a9a08845	61	__poll_t mask = EPOLLOUT \| EPOLLWRNORM;
1da177e4 LT	62
1da177e4 LT	63	poll_wait(file, &vcp->vc_waitq, wait);
da47c19e	64	mutex_lock(&vcp->vc_mutex);
1da177e4	65	if (!list_empty(&vcp->vc_pending))
a9a08845	66	mask \|= EPOLLIN \| EPOLLRDNORM;
da47c19e	67	mutex_unlock(&vcp->vc_mutex);
1da177e4 LT	68
	69	return mask;
	70	}
	71
97718390	72	static long coda_psdev_ioctl(struct file * filp, unsigned int cmd, unsigned long arg)
1da177e4 LT	73	{
	74	unsigned int data;
	75
	76	switch(cmd) {
	77	case CIOC_KERNEL_VERSION:
	78	data = CODA_KERNEL_VERSION;
	79	return put_user(data, (int __user *) arg);
	80	default:
	81	return -ENOTTY;
	82	}
	83
	84	return 0;
	85	}
	86
	87	/*
	88	* Receive a message written by Venus to the psdev
	89	*/
	90
	91	static ssize_t coda_psdev_write(struct file file, const char __user buf,
	92	size_t nbytes, loff_t *off)
	93	{
	94	struct venus_comm vcp = (struct venus_comm ) file->private_data;
	95	struct upc_req *req = NULL;
	96	struct upc_req *tmp;
	97	struct list_head *lh;
	98	struct coda_in_hdr hdr;
	99	ssize_t retval = 0, count = 0;
	100	int error;
	101
6e51f8aa JH	102	/* make sure there is enough to copy out the (opcode, unique) values */
	103	if (nbytes < (2 * sizeof(u_int32_t)))
	104	return -EINVAL;
	105
1da177e4	106	/* Peek at the opcode, uniquefier */
6e51f8aa	107	if (copy_from_user(&hdr, buf, 2 * sizeof(u_int32_t)))
1da177e4 LT	108	return -EFAULT;
	109
	110	if (DOWNCALL(hdr.opcode)) {
f7cc02b8	111	union outputArgs *dcbuf;
1da177e4 LT	112	int size = sizeof(*dcbuf);
1da177e4 LT	113
1da177e4	114	if ( nbytes < sizeof(struct coda_out_hdr) ) {
d9b4b319 FF	115	pr_warn("coda_downcall opc %d uniq %d, not enough!\n",
d9b4b319 FF	116	hdr.opcode, hdr.unique);
1da177e4 LT	117	count = nbytes;
	118	goto out;
	119	}
	120	if ( nbytes > size ) {
f38cfb25	121	pr_warn("downcall opc %d, uniq %d, too much!",
d9b4b319	122	hdr.opcode, hdr.unique);
1da177e4 LT	123	nbytes = size;
1da177e4 LT	124	}
4dc48193 DC	125	dcbuf = kvmalloc(nbytes, GFP_KERNEL);
	126	if (!dcbuf) {
	127	retval = -ENOMEM;
	128	goto out;
	129	}
1da177e4	130	if (copy_from_user(dcbuf, buf, nbytes)) {
936dae45	131	kvfree(dcbuf);
1da177e4 LT	132	retval = -EFAULT;
	133	goto out;
	134	}
	135
	136	/* what downcall errors does Venus handle ? */
6e51f8aa	137	error = coda_downcall(vcp, hdr.opcode, dcbuf, nbytes);
1da177e4	138
936dae45	139	kvfree(dcbuf);
1da177e4	140	if (error) {
6d6bd94f FF	141	pr_warn("%s: coda_downcall error: %d\n",
6d6bd94f FF	142	__func__, error);
1da177e4 LT	143	retval = error;
	144	goto out;
	145	}
	146	count = nbytes;
	147	goto out;
	148	}
	149
	150	/* Look for the message on the processing queue. */
da47c19e	151	mutex_lock(&vcp->vc_mutex);
1da177e4 LT	152	list_for_each(lh, &vcp->vc_processing) {
	153	tmp = list_entry(lh, struct upc_req , uc_chain);
	154	if (tmp->uc_unique == hdr.unique) {
	155	req = tmp;
	156	list_del(&req->uc_chain);
	157	break;
	158	}
	159	}
da47c19e	160	mutex_unlock(&vcp->vc_mutex);
1da177e4 LT	161
1da177e4 LT	162	if (!req) {
6d6bd94f FF	163	pr_warn("%s: msg (%d, %d) not found\n",
6d6bd94f FF	164	__func__, hdr.opcode, hdr.unique);
1da177e4 LT	165	retval = -ESRCH;
	166	goto out;
	167	}
	168
	169	/* move data into response buffer. */
	170	if (req->uc_outSize < nbytes) {
6d6bd94f FF	171	pr_warn("%s: too much cnt: %d, cnt: %ld, opc: %d, uniq: %d.\n",
	172	__func__, req->uc_outSize, (long)nbytes,
	173	hdr.opcode, hdr.unique);
1da177e4 LT	174	nbytes = req->uc_outSize; /* don't have more space! */
	175	}
	176	if (copy_from_user(req->uc_data, buf, nbytes)) {
4aeefdc6	177	req->uc_flags \|= CODA_REQ_ABORT;
1da177e4 LT	178	wake_up(&req->uc_sleep);
	179	retval = -EFAULT;
	180	goto out;
	181	}
	182
	183	/* adjust outsize. is this useful ?? */
112d421d JH	184	req->uc_outSize = nbytes;
112d421d JH	185	req->uc_flags \|= CODA_REQ_WRITE;
1da177e4 LT	186	count = nbytes;
	187
	188	/* Convert filedescriptor into a file handle */
	189	if (req->uc_opcode == CODA_OPEN_BY_FD) {
	190	struct coda_open_by_fd_out *outp =
	191	(struct coda_open_by_fd_out *)req->uc_data;
02551c23	192	if (!outp->oh.result) {
38c2e437	193	outp->fh = fget(outp->fd);
02551c23 ZJ	194	if (!outp->fh)
	195	return -EBADF;
	196	}
1da177e4 LT	197	}
	198
	199	wake_up(&req->uc_sleep);
	200	out:
	201	return(count ? count : retval);
	202	}
	203
	204	/*
	205	* Read a message from the kernel to Venus
	206	*/
	207
	208	static ssize_t coda_psdev_read(struct file * file, char __user * buf,
	209	size_t nbytes, loff_t *off)
	210	{
	211	DECLARE_WAITQUEUE(wait, current);
	212	struct venus_comm vcp = (struct venus_comm ) file->private_data;
	213	struct upc_req *req;
	214	ssize_t retval = 0, count = 0;
	215
	216	if (nbytes == 0)
	217	return 0;
	218
da47c19e	219	mutex_lock(&vcp->vc_mutex);
1da177e4 LT	220
	221	add_wait_queue(&vcp->vc_waitq, &wait);
	222	set_current_state(TASK_INTERRUPTIBLE);
	223
	224	while (list_empty(&vcp->vc_pending)) {
	225	if (file->f_flags & O_NONBLOCK) {
	226	retval = -EAGAIN;
	227	break;
	228	}
	229	if (signal_pending(current)) {
	230	retval = -ERESTARTSYS;
	231	break;
	232	}
da47c19e	233	mutex_unlock(&vcp->vc_mutex);
1da177e4	234	schedule();
da47c19e	235	mutex_lock(&vcp->vc_mutex);
1da177e4 LT	236	}
	237
	238	set_current_state(TASK_RUNNING);
	239	remove_wait_queue(&vcp->vc_waitq, &wait);
	240
	241	if (retval)
	242	goto out;
	243
	244	req = list_entry(vcp->vc_pending.next, struct upc_req,uc_chain);
	245	list_del(&req->uc_chain);
	246
	247	/* Move the input args into userspace */
	248	count = req->uc_inSize;
	249	if (nbytes < req->uc_inSize) {
6d6bd94f FF	250	pr_warn("%s: Venus read %ld bytes of %d in message\n",
6d6bd94f FF	251	__func__, (long)nbytes, req->uc_inSize);
1da177e4 LT	252	count = nbytes;
	253	}
	254
	255	if (copy_to_user(buf, req->uc_data, count))
	256	retval = -EFAULT;
	257
	258	/* If request was not a signal, enqueue and don't free */
4aeefdc6 JA	259	if (!(req->uc_flags & CODA_REQ_ASYNC)) {
4aeefdc6 JA	260	req->uc_flags \|= CODA_REQ_READ;
8e13059a	261	list_add_tail(&(req->uc_chain), &vcp->vc_processing);
1da177e4 LT	262	goto out;
	263	}
	264
936dae45	265	kvfree(req->uc_data);
37461e19	266	kfree(req);
1da177e4	267	out:
da47c19e	268	mutex_unlock(&vcp->vc_mutex);
1da177e4 LT	269	return (count ? count : retval);
	270	}
	271
	272	static int coda_psdev_open(struct inode * inode, struct file * file)
	273	{
87065519 JH	274	struct venus_comm *vcp;
87065519 JH	275	int idx, err;
1da177e4	276
9fd973e0 EB	277	if (task_active_pid_ns(current) != &init_pid_ns)
	278	return -EINVAL;
	279
d83f5901 EB	280	if (current_user_ns() != &init_user_ns)
	281	return -EINVAL;
	282
1da177e4	283	idx = iminor(inode);
87065519	284	if (idx < 0 \|\| idx >= MAX_CODADEVS)
1da177e4	285	return -ENODEV;
1da177e4	286
87065519	287	err = -EBUSY;
1da177e4	288	vcp = &coda_comms[idx];
da47c19e YA	289	mutex_lock(&vcp->vc_mutex);
da47c19e YA	290
87065519 JH	291	if (!vcp->vc_inuse) {
	292	vcp->vc_inuse++;
	293
1da177e4 LT	294	INIT_LIST_HEAD(&vcp->vc_pending);
	295	INIT_LIST_HEAD(&vcp->vc_processing);
	296	init_waitqueue_head(&vcp->vc_waitq);
	297	vcp->vc_sb = NULL;
	298	vcp->vc_seq = 0;
87065519 JH	299
	300	file->private_data = vcp;
	301	err = 0;
1da177e4	302	}
1da177e4	303
da47c19e	304	mutex_unlock(&vcp->vc_mutex);
87065519	305	return err;
1da177e4 LT	306	}
	307
	308
	309	static int coda_psdev_release(struct inode * inode, struct file * file)
	310	{
87065519 JH	311	struct venus_comm vcp = (struct venus_comm ) file->private_data;
87065519 JH	312	struct upc_req req, tmp;
1da177e4	313
87065519	314	if (!vcp \|\| !vcp->vc_inuse ) {
6d6bd94f	315	pr_warn("%s: Not open.\n", __func__);
1da177e4 LT	316	return -1;
	317	}
	318
da47c19e	319	mutex_lock(&vcp->vc_mutex);
87065519 JH	320
87065519 JH	321	/* Wakeup clients so they can return. */
1da177e4	322	list_for_each_entry_safe(req, tmp, &vcp->vc_pending, uc_chain) {
87065519 JH	323	list_del(&req->uc_chain);
87065519 JH	324
1da177e4	325	/* Async requests need to be freed here */
4aeefdc6	326	if (req->uc_flags & CODA_REQ_ASYNC) {
936dae45	327	kvfree(req->uc_data);
37461e19	328	kfree(req);
1da177e4 LT	329	continue;
1da177e4 LT	330	}
4aeefdc6	331	req->uc_flags \|= CODA_REQ_ABORT;
1da177e4	332	wake_up(&req->uc_sleep);
87065519 JH	333	}
	334
	335	list_for_each_entry_safe(req, tmp, &vcp->vc_processing, uc_chain) {
	336	list_del(&req->uc_chain);
	337
4aeefdc6	338	req->uc_flags \|= CODA_REQ_ABORT;
87065519 JH	339	wake_up(&req->uc_sleep);
87065519 JH	340	}
1da177e4	341
87065519 JH	342	file->private_data = NULL;
87065519 JH	343	vcp->vc_inuse--;
da47c19e	344	mutex_unlock(&vcp->vc_mutex);
1da177e4 LT	345	return 0;
	346	}
	347
	348
4b6f5d20	349	static const struct file_operations coda_psdev_fops = {
1da177e4 LT	350	.owner = THIS_MODULE,
	351	.read = coda_psdev_read,
	352	.write = coda_psdev_write,
	353	.poll = coda_psdev_poll,
97718390	354	.unlocked_ioctl = coda_psdev_ioctl,
1da177e4 LT	355	.open = coda_psdev_open,
1da177e4 LT	356	.release = coda_psdev_release,
6038f373	357	.llseek = noop_llseek,
1da177e4 LT	358	};
1da177e4 LT	359
f9484528	360	static int __init init_coda_psdev(void)
1da177e4 LT	361	{
	362	int i, err = 0;
	363	if (register_chrdev(CODA_PSDEV_MAJOR, "coda", &coda_psdev_fops)) {
6d6bd94f FF	364	pr_err("%s: unable to get major %d\n",
6d6bd94f FF	365	__func__, CODA_PSDEV_MAJOR);
85062213	366	return -EIO;
1da177e4	367	}
1db560af	368	coda_psdev_class = class_create(THIS_MODULE, "coda");
1da177e4 LT	369	if (IS_ERR(coda_psdev_class)) {
	370	err = PTR_ERR(coda_psdev_class);
	371	goto out_chrdev;
	372	}
da47c19e YA	373	for (i = 0; i < MAX_CODADEVS; i++) {
da47c19e YA	374	mutex_init(&(&coda_comms[i])->vc_mutex);
a9b12619 GKH	375	device_create(coda_psdev_class, NULL,
a9b12619 GKH	376	MKDEV(CODA_PSDEV_MAJOR, i), NULL, "cfs%d", i);
da47c19e	377	}
1da177e4 LT	378	coda_sysctl_init();
	379	goto out;
	380
1da177e4 LT	381	out_chrdev:
	382	unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
	383	out:
	384	return err;
	385	}
	386
5b7f13bd JH	387	MODULE_AUTHOR("Jan Harkes, Peter J. Braam");
	388	MODULE_DESCRIPTION("Coda Distributed File System VFS interface");
	389	MODULE_ALIAS_CHARDEV_MAJOR(CODA_PSDEV_MAJOR);
1da177e4	390	MODULE_LICENSE("GPL");
a9fba24c	391	MODULE_VERSION("7.0");
1da177e4	392
1da177e4 LT	393	static int __init init_coda(void)
	394	{
	395	int status;
	396	int i;
1da177e4 LT	397
	398	status = coda_init_inodecache();
	399	if (status)
	400	goto out2;
	401	status = init_coda_psdev();
	402	if ( status ) {
d9b4b319	403	pr_warn("Problem (%d) in init_coda_psdev\n", status);
1da177e4 LT	404	goto out1;
	405	}
	406
	407	status = register_filesystem(&coda_fs_type);
	408	if (status) {
f38cfb25	409	pr_warn("failed to register filesystem!\n");
1da177e4 LT	410	goto out;
	411	}
	412	return 0;
	413	out:
8ab5e4c1	414	for (i = 0; i < MAX_CODADEVS; i++)
62ca8792	415	device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
1db560af	416	class_destroy(coda_psdev_class);
1da177e4 LT	417	unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
	418	coda_sysctl_clean();
	419	out1:
	420	coda_destroy_inodecache();
	421	out2:
	422	return status;
	423	}
	424
	425	static void __exit exit_coda(void)
	426	{
	427	int err, i;
	428
	429	err = unregister_filesystem(&coda_fs_type);
d9b4b319	430	if (err != 0)
f38cfb25	431	pr_warn("failed to unregister filesystem\n");
8ab5e4c1	432	for (i = 0; i < MAX_CODADEVS; i++)
62ca8792	433	device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
1db560af	434	class_destroy(coda_psdev_class);
1da177e4 LT	435	unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
	436	coda_sysctl_clean();
	437	coda_destroy_inodecache();
	438	}
	439
	440	module_init(init_coda);
	441	module_exit(exit_coda);
	442