blob: 0376ac66c44a6127199c5389f33f138f73c53fba [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * An implementation of a loadable kernel mode driver providing
3 * multiple kernel/user space bidirectional communications links.
4 *
Alan Cox526719b2008-10-27 15:19:48 +00005 * Author: Alan Cox <alan@lxorguk.ukuu.org.uk>
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 *
12 * Adapted to become the Linux 2.0 Coda pseudo device
13 * Peter Braam <braam@maths.ox.ac.uk>
14 * Michael Callahan <mjc@emmy.smith.edu>
15 *
16 * Changes for Linux 2.1
17 * Copyright (c) 1997 Carnegie-Mellon University
18 */
19
20#include <linux/module.h>
21#include <linux/errno.h>
22#include <linux/kernel.h>
23#include <linux/major.h>
24#include <linux/time.h>
25#include <linux/slab.h>
26#include <linux/ioport.h>
27#include <linux/fcntl.h>
28#include <linux/delay.h>
29#include <linux/skbuff.h>
30#include <linux/proc_fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031#include <linux/vmalloc.h>
32#include <linux/fs.h>
33#include <linux/file.h>
34#include <linux/poll.h>
35#include <linux/init.h>
36#include <linux/list.h>
37#include <linux/smp_lock.h>
38#include <linux/device.h>
39#include <asm/io.h>
40#include <asm/system.h>
41#include <asm/poll.h>
42#include <asm/uaccess.h>
43
44#include <linux/coda.h>
45#include <linux/coda_linux.h>
46#include <linux/coda_fs_i.h>
47#include <linux/coda_psdev.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070048
Adrian Bunkc98d8cf2006-03-24 03:15:53 -080049#include "coda_int.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
Linus Torvalds1da177e2005-04-16 15:20:36 -070051/* statistics */
52int coda_hard; /* allows signals during upcalls */
53unsigned long coda_timeout = 30; /* .. secs, then signals will dequeue */
54
55
56struct venus_comm coda_comms[MAX_CODADEVS];
gregkh@suse.de1db560a2005-03-23 10:02:26 -080057static struct class *coda_psdev_class;
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
59/*
60 * Device operations
61 */
62
63static unsigned int coda_psdev_poll(struct file *file, poll_table * wait)
64{
65 struct venus_comm *vcp = (struct venus_comm *) file->private_data;
66 unsigned int mask = POLLOUT | POLLWRNORM;
67
68 poll_wait(file, &vcp->vc_waitq, wait);
69 if (!list_empty(&vcp->vc_pending))
70 mask |= POLLIN | POLLRDNORM;
71
72 return mask;
73}
74
75static int coda_psdev_ioctl(struct inode * inode, struct file * filp,
76 unsigned int cmd, unsigned long arg)
77{
78 unsigned int data;
79
80 switch(cmd) {
81 case CIOC_KERNEL_VERSION:
82 data = CODA_KERNEL_VERSION;
83 return put_user(data, (int __user *) arg);
84 default:
85 return -ENOTTY;
86 }
87
88 return 0;
89}
90
91/*
92 * Receive a message written by Venus to the psdev
93 */
94
95static ssize_t coda_psdev_write(struct file *file, const char __user *buf,
96 size_t nbytes, loff_t *off)
97{
98 struct venus_comm *vcp = (struct venus_comm *) file->private_data;
99 struct upc_req *req = NULL;
100 struct upc_req *tmp;
101 struct list_head *lh;
102 struct coda_in_hdr hdr;
103 ssize_t retval = 0, count = 0;
104 int error;
105
106 /* Peek at the opcode, uniquefier */
107 if (copy_from_user(&hdr, buf, 2 * sizeof(u_long)))
108 return -EFAULT;
109
110 if (DOWNCALL(hdr.opcode)) {
111 struct super_block *sb = NULL;
112 union outputArgs *dcbuf;
113 int size = sizeof(*dcbuf);
114
115 sb = vcp->vc_sb;
116 if ( !sb ) {
117 count = nbytes;
118 goto out;
119 }
120
121 if ( nbytes < sizeof(struct coda_out_hdr) ) {
122 printk("coda_downcall opc %d uniq %d, not enough!\n",
123 hdr.opcode, hdr.unique);
124 count = nbytes;
125 goto out;
126 }
127 if ( nbytes > size ) {
128 printk("Coda: downcall opc %d, uniq %d, too much!",
129 hdr.opcode, hdr.unique);
130 nbytes = size;
131 }
132 CODA_ALLOC(dcbuf, union outputArgs *, nbytes);
133 if (copy_from_user(dcbuf, buf, nbytes)) {
134 CODA_FREE(dcbuf, nbytes);
135 retval = -EFAULT;
136 goto out;
137 }
138
139 /* what downcall errors does Venus handle ? */
140 lock_kernel();
141 error = coda_downcall(hdr.opcode, dcbuf, sb);
142 unlock_kernel();
143
144 CODA_FREE(dcbuf, nbytes);
145 if (error) {
146 printk("psdev_write: coda_downcall error: %d\n", error);
147 retval = error;
148 goto out;
149 }
150 count = nbytes;
151 goto out;
152 }
153
154 /* Look for the message on the processing queue. */
155 lock_kernel();
156 list_for_each(lh, &vcp->vc_processing) {
157 tmp = list_entry(lh, struct upc_req , uc_chain);
158 if (tmp->uc_unique == hdr.unique) {
159 req = tmp;
160 list_del(&req->uc_chain);
161 break;
162 }
163 }
164 unlock_kernel();
165
166 if (!req) {
167 printk("psdev_write: msg (%d, %d) not found\n",
168 hdr.opcode, hdr.unique);
169 retval = -ESRCH;
170 goto out;
171 }
172
173 /* move data into response buffer. */
174 if (req->uc_outSize < nbytes) {
175 printk("psdev_write: too much cnt: %d, cnt: %ld, opc: %d, uniq: %d.\n",
176 req->uc_outSize, (long)nbytes, hdr.opcode, hdr.unique);
177 nbytes = req->uc_outSize; /* don't have more space! */
178 }
179 if (copy_from_user(req->uc_data, buf, nbytes)) {
180 req->uc_flags |= REQ_ABORT;
181 wake_up(&req->uc_sleep);
182 retval = -EFAULT;
183 goto out;
184 }
185
186 /* adjust outsize. is this useful ?? */
187 req->uc_outSize = nbytes;
188 req->uc_flags |= REQ_WRITE;
189 count = nbytes;
190
191 /* Convert filedescriptor into a file handle */
192 if (req->uc_opcode == CODA_OPEN_BY_FD) {
193 struct coda_open_by_fd_out *outp =
194 (struct coda_open_by_fd_out *)req->uc_data;
Jan Harkes38c2e432007-07-19 01:48:41 -0700195 if (!outp->oh.result)
196 outp->fh = fget(outp->fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 }
198
199 wake_up(&req->uc_sleep);
200out:
201 return(count ? count : retval);
202}
203
204/*
205 * Read a message from the kernel to Venus
206 */
207
208static 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
219 lock_kernel();
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 }
233 schedule();
234 }
235
236 set_current_state(TASK_RUNNING);
237 remove_wait_queue(&vcp->vc_waitq, &wait);
238
239 if (retval)
240 goto out;
241
242 req = list_entry(vcp->vc_pending.next, struct upc_req,uc_chain);
243 list_del(&req->uc_chain);
244
245 /* Move the input args into userspace */
246 count = req->uc_inSize;
247 if (nbytes < req->uc_inSize) {
248 printk ("psdev_read: Venus read %ld bytes of %d in message\n",
249 (long)nbytes, req->uc_inSize);
250 count = nbytes;
251 }
252
253 if (copy_to_user(buf, req->uc_data, count))
254 retval = -EFAULT;
255
256 /* If request was not a signal, enqueue and don't free */
257 if (!(req->uc_flags & REQ_ASYNC)) {
258 req->uc_flags |= REQ_READ;
Akinobu Mita8e130592006-06-26 00:24:37 -0700259 list_add_tail(&(req->uc_chain), &vcp->vc_processing);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260 goto out;
261 }
262
263 CODA_FREE(req->uc_data, sizeof(struct coda_in_hdr));
Jan Harkes37461e12007-07-19 01:48:48 -0700264 kfree(req);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265out:
266 unlock_kernel();
267 return (count ? count : retval);
268}
269
270static int coda_psdev_open(struct inode * inode, struct file * file)
271{
Jan Harkes87065512007-07-19 01:48:45 -0700272 struct venus_comm *vcp;
273 int idx, err;
274
275 idx = iminor(inode);
276 if (idx < 0 || idx >= MAX_CODADEVS)
277 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278
279 lock_kernel();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280
Jan Harkes87065512007-07-19 01:48:45 -0700281 err = -EBUSY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 vcp = &coda_comms[idx];
Jan Harkes87065512007-07-19 01:48:45 -0700283 if (!vcp->vc_inuse) {
284 vcp->vc_inuse++;
285
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286 INIT_LIST_HEAD(&vcp->vc_pending);
287 INIT_LIST_HEAD(&vcp->vc_processing);
288 init_waitqueue_head(&vcp->vc_waitq);
289 vcp->vc_sb = NULL;
290 vcp->vc_seq = 0;
Jan Harkes87065512007-07-19 01:48:45 -0700291
292 file->private_data = vcp;
293 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295
296 unlock_kernel();
Jan Harkes87065512007-07-19 01:48:45 -0700297 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298}
299
300
301static int coda_psdev_release(struct inode * inode, struct file * file)
302{
Jan Harkes87065512007-07-19 01:48:45 -0700303 struct venus_comm *vcp = (struct venus_comm *) file->private_data;
304 struct upc_req *req, *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305
Jan Harkes87065512007-07-19 01:48:45 -0700306 if (!vcp || !vcp->vc_inuse ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 printk("psdev_release: Not open.\n");
308 return -1;
309 }
310
Jan Harkes87065512007-07-19 01:48:45 -0700311 lock_kernel();
312
313 /* Wakeup clients so they can return. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 list_for_each_entry_safe(req, tmp, &vcp->vc_pending, uc_chain) {
Jan Harkes87065512007-07-19 01:48:45 -0700315 list_del(&req->uc_chain);
316
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 /* Async requests need to be freed here */
318 if (req->uc_flags & REQ_ASYNC) {
319 CODA_FREE(req->uc_data, sizeof(struct coda_in_hdr));
Jan Harkes37461e12007-07-19 01:48:48 -0700320 kfree(req);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 continue;
322 }
323 req->uc_flags |= REQ_ABORT;
324 wake_up(&req->uc_sleep);
Jan Harkes87065512007-07-19 01:48:45 -0700325 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326
Jan Harkes87065512007-07-19 01:48:45 -0700327 list_for_each_entry_safe(req, tmp, &vcp->vc_processing, uc_chain) {
328 list_del(&req->uc_chain);
329
330 req->uc_flags |= REQ_ABORT;
331 wake_up(&req->uc_sleep);
332 }
333
334 file->private_data = NULL;
335 vcp->vc_inuse--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 unlock_kernel();
337 return 0;
338}
339
340
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800341static const struct file_operations coda_psdev_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342 .owner = THIS_MODULE,
343 .read = coda_psdev_read,
344 .write = coda_psdev_write,
345 .poll = coda_psdev_poll,
346 .ioctl = coda_psdev_ioctl,
347 .open = coda_psdev_open,
348 .release = coda_psdev_release,
349};
350
351static int init_coda_psdev(void)
352{
353 int i, err = 0;
354 if (register_chrdev(CODA_PSDEV_MAJOR, "coda", &coda_psdev_fops)) {
355 printk(KERN_ERR "coda_psdev: unable to get major %d\n",
356 CODA_PSDEV_MAJOR);
357 return -EIO;
358 }
gregkh@suse.de1db560a2005-03-23 10:02:26 -0800359 coda_psdev_class = class_create(THIS_MODULE, "coda");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360 if (IS_ERR(coda_psdev_class)) {
361 err = PTR_ERR(coda_psdev_class);
362 goto out_chrdev;
363 }
Greg Kroah-Hartman7c69ef72005-06-20 21:15:16 -0700364 for (i = 0; i < MAX_CODADEVS; i++)
Greg Kroah-Hartmana9b12612008-07-21 20:03:34 -0700365 device_create(coda_psdev_class, NULL,
366 MKDEV(CODA_PSDEV_MAJOR, i), NULL, "cfs%d", i);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 coda_sysctl_init();
368 goto out;
369
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370out_chrdev:
371 unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
372out:
373 return err;
374}
375
Jan Harkes5b7f13b2007-07-19 01:48:52 -0700376MODULE_AUTHOR("Jan Harkes, Peter J. Braam");
377MODULE_DESCRIPTION("Coda Distributed File System VFS interface");
378MODULE_ALIAS_CHARDEV_MAJOR(CODA_PSDEV_MAJOR);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379MODULE_LICENSE("GPL");
Jan Harkes5b7f13b2007-07-19 01:48:52 -0700380MODULE_VERSION("6.6");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382static int __init init_coda(void)
383{
384 int status;
385 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386
387 status = coda_init_inodecache();
388 if (status)
389 goto out2;
390 status = init_coda_psdev();
391 if ( status ) {
392 printk("Problem (%d) in init_coda_psdev\n", status);
393 goto out1;
394 }
395
396 status = register_filesystem(&coda_fs_type);
397 if (status) {
398 printk("coda: failed to register filesystem!\n");
399 goto out;
400 }
401 return 0;
402out:
Greg Kroah-Hartman8ab5e4c2005-06-20 21:15:16 -0700403 for (i = 0; i < MAX_CODADEVS; i++)
Kay Sievers62ca8792007-09-25 02:03:03 +0200404 device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
gregkh@suse.de1db560a2005-03-23 10:02:26 -0800405 class_destroy(coda_psdev_class);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406 unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
407 coda_sysctl_clean();
408out1:
409 coda_destroy_inodecache();
410out2:
411 return status;
412}
413
414static void __exit exit_coda(void)
415{
416 int err, i;
417
418 err = unregister_filesystem(&coda_fs_type);
419 if ( err != 0 ) {
420 printk("coda: failed to unregister filesystem\n");
421 }
Greg Kroah-Hartman8ab5e4c2005-06-20 21:15:16 -0700422 for (i = 0; i < MAX_CODADEVS; i++)
Kay Sievers62ca8792007-09-25 02:03:03 +0200423 device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
gregkh@suse.de1db560a2005-03-23 10:02:26 -0800424 class_destroy(coda_psdev_class);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425 unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
426 coda_sysctl_clean();
427 coda_destroy_inodecache();
428}
429
430module_init(init_coda);
431module_exit(exit_coda);
432