blob: be4392ca20983345ae180a450fd0497442b135a8 [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>
Alexey Dobriyana99bbaf2009-10-04 16:11:37 +040025#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/slab.h>
27#include <linux/ioport.h>
28#include <linux/fcntl.h>
29#include <linux/delay.h>
30#include <linux/skbuff.h>
31#include <linux/proc_fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#include <linux/vmalloc.h>
33#include <linux/fs.h>
34#include <linux/file.h>
35#include <linux/poll.h>
36#include <linux/init.h>
37#include <linux/list.h>
38#include <linux/smp_lock.h>
39#include <linux/device.h>
40#include <asm/io.h>
41#include <asm/system.h>
42#include <asm/poll.h>
43#include <asm/uaccess.h>
44
45#include <linux/coda.h>
46#include <linux/coda_linux.h>
47#include <linux/coda_fs_i.h>
48#include <linux/coda_psdev.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
Adrian Bunkc98d8cf2006-03-24 03:15:53 -080050#include "coda_int.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
Linus Torvalds1da177e2005-04-16 15:20:36 -070052/* statistics */
53int coda_hard; /* allows signals during upcalls */
54unsigned long coda_timeout = 30; /* .. secs, then signals will dequeue */
55
56
57struct venus_comm coda_comms[MAX_CODADEVS];
gregkh@suse.de1db560a2005-03-23 10:02:26 -080058static struct class *coda_psdev_class;
Linus Torvalds1da177e2005-04-16 15:20:36 -070059
60/*
61 * Device operations
62 */
63
64static unsigned int coda_psdev_poll(struct file *file, poll_table * wait)
65{
66 struct venus_comm *vcp = (struct venus_comm *) file->private_data;
67 unsigned int mask = POLLOUT | POLLWRNORM;
68
69 poll_wait(file, &vcp->vc_waitq, wait);
70 if (!list_empty(&vcp->vc_pending))
71 mask |= POLLIN | POLLRDNORM;
72
73 return mask;
74}
75
76static int coda_psdev_ioctl(struct inode * inode, struct file * filp,
77 unsigned int cmd, unsigned long arg)
78{
79 unsigned int data;
80
81 switch(cmd) {
82 case CIOC_KERNEL_VERSION:
83 data = CODA_KERNEL_VERSION;
84 return put_user(data, (int __user *) arg);
85 default:
86 return -ENOTTY;
87 }
88
89 return 0;
90}
91
92/*
93 * Receive a message written by Venus to the psdev
94 */
95
96static ssize_t coda_psdev_write(struct file *file, const char __user *buf,
97 size_t nbytes, loff_t *off)
98{
99 struct venus_comm *vcp = (struct venus_comm *) file->private_data;
100 struct upc_req *req = NULL;
101 struct upc_req *tmp;
102 struct list_head *lh;
103 struct coda_in_hdr hdr;
104 ssize_t retval = 0, count = 0;
105 int error;
106
107 /* Peek at the opcode, uniquefier */
108 if (copy_from_user(&hdr, buf, 2 * sizeof(u_long)))
109 return -EFAULT;
110
111 if (DOWNCALL(hdr.opcode)) {
112 struct super_block *sb = NULL;
113 union outputArgs *dcbuf;
114 int size = sizeof(*dcbuf);
115
116 sb = vcp->vc_sb;
117 if ( !sb ) {
118 count = nbytes;
119 goto out;
120 }
121
122 if ( nbytes < sizeof(struct coda_out_hdr) ) {
123 printk("coda_downcall opc %d uniq %d, not enough!\n",
124 hdr.opcode, hdr.unique);
125 count = nbytes;
126 goto out;
127 }
128 if ( nbytes > size ) {
129 printk("Coda: downcall opc %d, uniq %d, too much!",
130 hdr.opcode, hdr.unique);
131 nbytes = size;
132 }
133 CODA_ALLOC(dcbuf, union outputArgs *, nbytes);
134 if (copy_from_user(dcbuf, buf, nbytes)) {
135 CODA_FREE(dcbuf, nbytes);
136 retval = -EFAULT;
137 goto out;
138 }
139
140 /* what downcall errors does Venus handle ? */
141 lock_kernel();
142 error = coda_downcall(hdr.opcode, dcbuf, sb);
143 unlock_kernel();
144
145 CODA_FREE(dcbuf, nbytes);
146 if (error) {
147 printk("psdev_write: coda_downcall error: %d\n", error);
148 retval = error;
149 goto out;
150 }
151 count = nbytes;
152 goto out;
153 }
154
155 /* Look for the message on the processing queue. */
156 lock_kernel();
157 list_for_each(lh, &vcp->vc_processing) {
158 tmp = list_entry(lh, struct upc_req , uc_chain);
159 if (tmp->uc_unique == hdr.unique) {
160 req = tmp;
161 list_del(&req->uc_chain);
162 break;
163 }
164 }
165 unlock_kernel();
166
167 if (!req) {
168 printk("psdev_write: msg (%d, %d) not found\n",
169 hdr.opcode, hdr.unique);
170 retval = -ESRCH;
171 goto out;
172 }
173
174 /* move data into response buffer. */
175 if (req->uc_outSize < nbytes) {
176 printk("psdev_write: too much cnt: %d, cnt: %ld, opc: %d, uniq: %d.\n",
177 req->uc_outSize, (long)nbytes, hdr.opcode, hdr.unique);
178 nbytes = req->uc_outSize; /* don't have more space! */
179 }
180 if (copy_from_user(req->uc_data, buf, nbytes)) {
181 req->uc_flags |= REQ_ABORT;
182 wake_up(&req->uc_sleep);
183 retval = -EFAULT;
184 goto out;
185 }
186
187 /* adjust outsize. is this useful ?? */
188 req->uc_outSize = nbytes;
189 req->uc_flags |= REQ_WRITE;
190 count = nbytes;
191
192 /* Convert filedescriptor into a file handle */
193 if (req->uc_opcode == CODA_OPEN_BY_FD) {
194 struct coda_open_by_fd_out *outp =
195 (struct coda_open_by_fd_out *)req->uc_data;
Jan Harkes38c2e432007-07-19 01:48:41 -0700196 if (!outp->oh.result)
197 outp->fh = fget(outp->fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 }
199
200 wake_up(&req->uc_sleep);
201out:
202 return(count ? count : retval);
203}
204
205/*
206 * Read a message from the kernel to Venus
207 */
208
209static ssize_t coda_psdev_read(struct file * file, char __user * buf,
210 size_t nbytes, loff_t *off)
211{
212 DECLARE_WAITQUEUE(wait, current);
213 struct venus_comm *vcp = (struct venus_comm *) file->private_data;
214 struct upc_req *req;
215 ssize_t retval = 0, count = 0;
216
217 if (nbytes == 0)
218 return 0;
219
220 lock_kernel();
221
222 add_wait_queue(&vcp->vc_waitq, &wait);
223 set_current_state(TASK_INTERRUPTIBLE);
224
225 while (list_empty(&vcp->vc_pending)) {
226 if (file->f_flags & O_NONBLOCK) {
227 retval = -EAGAIN;
228 break;
229 }
230 if (signal_pending(current)) {
231 retval = -ERESTARTSYS;
232 break;
233 }
234 schedule();
235 }
236
237 set_current_state(TASK_RUNNING);
238 remove_wait_queue(&vcp->vc_waitq, &wait);
239
240 if (retval)
241 goto out;
242
243 req = list_entry(vcp->vc_pending.next, struct upc_req,uc_chain);
244 list_del(&req->uc_chain);
245
246 /* Move the input args into userspace */
247 count = req->uc_inSize;
248 if (nbytes < req->uc_inSize) {
249 printk ("psdev_read: Venus read %ld bytes of %d in message\n",
250 (long)nbytes, req->uc_inSize);
251 count = nbytes;
252 }
253
254 if (copy_to_user(buf, req->uc_data, count))
255 retval = -EFAULT;
256
257 /* If request was not a signal, enqueue and don't free */
258 if (!(req->uc_flags & REQ_ASYNC)) {
259 req->uc_flags |= REQ_READ;
Akinobu Mita8e130592006-06-26 00:24:37 -0700260 list_add_tail(&(req->uc_chain), &vcp->vc_processing);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 goto out;
262 }
263
264 CODA_FREE(req->uc_data, sizeof(struct coda_in_hdr));
Jan Harkes37461e12007-07-19 01:48:48 -0700265 kfree(req);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266out:
267 unlock_kernel();
268 return (count ? count : retval);
269}
270
271static int coda_psdev_open(struct inode * inode, struct file * file)
272{
Jan Harkes87065512007-07-19 01:48:45 -0700273 struct venus_comm *vcp;
274 int idx, err;
275
276 idx = iminor(inode);
277 if (idx < 0 || idx >= MAX_CODADEVS)
278 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279
280 lock_kernel();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281
Jan Harkes87065512007-07-19 01:48:45 -0700282 err = -EBUSY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 vcp = &coda_comms[idx];
Jan Harkes87065512007-07-19 01:48:45 -0700284 if (!vcp->vc_inuse) {
285 vcp->vc_inuse++;
286
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 INIT_LIST_HEAD(&vcp->vc_pending);
288 INIT_LIST_HEAD(&vcp->vc_processing);
289 init_waitqueue_head(&vcp->vc_waitq);
290 vcp->vc_sb = NULL;
291 vcp->vc_seq = 0;
Jan Harkes87065512007-07-19 01:48:45 -0700292
293 file->private_data = vcp;
294 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296
297 unlock_kernel();
Jan Harkes87065512007-07-19 01:48:45 -0700298 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299}
300
301
302static int coda_psdev_release(struct inode * inode, struct file * file)
303{
Jan Harkes87065512007-07-19 01:48:45 -0700304 struct venus_comm *vcp = (struct venus_comm *) file->private_data;
305 struct upc_req *req, *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306
Jan Harkes87065512007-07-19 01:48:45 -0700307 if (!vcp || !vcp->vc_inuse ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308 printk("psdev_release: Not open.\n");
309 return -1;
310 }
311
Jan Harkes87065512007-07-19 01:48:45 -0700312 lock_kernel();
313
314 /* Wakeup clients so they can return. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315 list_for_each_entry_safe(req, tmp, &vcp->vc_pending, uc_chain) {
Jan Harkes87065512007-07-19 01:48:45 -0700316 list_del(&req->uc_chain);
317
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318 /* Async requests need to be freed here */
319 if (req->uc_flags & REQ_ASYNC) {
320 CODA_FREE(req->uc_data, sizeof(struct coda_in_hdr));
Jan Harkes37461e12007-07-19 01:48:48 -0700321 kfree(req);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 continue;
323 }
324 req->uc_flags |= REQ_ABORT;
325 wake_up(&req->uc_sleep);
Jan Harkes87065512007-07-19 01:48:45 -0700326 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327
Jan Harkes87065512007-07-19 01:48:45 -0700328 list_for_each_entry_safe(req, tmp, &vcp->vc_processing, uc_chain) {
329 list_del(&req->uc_chain);
330
331 req->uc_flags |= REQ_ABORT;
332 wake_up(&req->uc_sleep);
333 }
334
335 file->private_data = NULL;
336 vcp->vc_inuse--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 unlock_kernel();
338 return 0;
339}
340
341
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800342static const struct file_operations coda_psdev_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 .owner = THIS_MODULE,
344 .read = coda_psdev_read,
345 .write = coda_psdev_write,
346 .poll = coda_psdev_poll,
347 .ioctl = coda_psdev_ioctl,
348 .open = coda_psdev_open,
349 .release = coda_psdev_release,
350};
351
352static int init_coda_psdev(void)
353{
354 int i, err = 0;
355 if (register_chrdev(CODA_PSDEV_MAJOR, "coda", &coda_psdev_fops)) {
356 printk(KERN_ERR "coda_psdev: unable to get major %d\n",
357 CODA_PSDEV_MAJOR);
358 return -EIO;
359 }
gregkh@suse.de1db560a2005-03-23 10:02:26 -0800360 coda_psdev_class = class_create(THIS_MODULE, "coda");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 if (IS_ERR(coda_psdev_class)) {
362 err = PTR_ERR(coda_psdev_class);
363 goto out_chrdev;
364 }
Greg Kroah-Hartman7c69ef72005-06-20 21:15:16 -0700365 for (i = 0; i < MAX_CODADEVS; i++)
Greg Kroah-Hartmana9b12612008-07-21 20:03:34 -0700366 device_create(coda_psdev_class, NULL,
367 MKDEV(CODA_PSDEV_MAJOR, i), NULL, "cfs%d", i);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368 coda_sysctl_init();
369 goto out;
370
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371out_chrdev:
372 unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
373out:
374 return err;
375}
376
Jan Harkes5b7f13b2007-07-19 01:48:52 -0700377MODULE_AUTHOR("Jan Harkes, Peter J. Braam");
378MODULE_DESCRIPTION("Coda Distributed File System VFS interface");
379MODULE_ALIAS_CHARDEV_MAJOR(CODA_PSDEV_MAJOR);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380MODULE_LICENSE("GPL");
Jan Harkes5b7f13b2007-07-19 01:48:52 -0700381MODULE_VERSION("6.6");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383static int __init init_coda(void)
384{
385 int status;
386 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387
388 status = coda_init_inodecache();
389 if (status)
390 goto out2;
391 status = init_coda_psdev();
392 if ( status ) {
393 printk("Problem (%d) in init_coda_psdev\n", status);
394 goto out1;
395 }
396
397 status = register_filesystem(&coda_fs_type);
398 if (status) {
399 printk("coda: failed to register filesystem!\n");
400 goto out;
401 }
402 return 0;
403out:
Greg Kroah-Hartman8ab5e4c2005-06-20 21:15:16 -0700404 for (i = 0; i < MAX_CODADEVS; i++)
Kay Sievers62ca8792007-09-25 02:03:03 +0200405 device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
gregkh@suse.de1db560a2005-03-23 10:02:26 -0800406 class_destroy(coda_psdev_class);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
408 coda_sysctl_clean();
409out1:
410 coda_destroy_inodecache();
411out2:
412 return status;
413}
414
415static void __exit exit_coda(void)
416{
417 int err, i;
418
419 err = unregister_filesystem(&coda_fs_type);
420 if ( err != 0 ) {
421 printk("coda: failed to unregister filesystem\n");
422 }
Greg Kroah-Hartman8ab5e4c2005-06-20 21:15:16 -0700423 for (i = 0; i < MAX_CODADEVS; i++)
Kay Sievers62ca8792007-09-25 02:03:03 +0200424 device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
gregkh@suse.de1db560a2005-03-23 10:02:26 -0800425 class_destroy(coda_psdev_class);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
427 coda_sysctl_clean();
428 coda_destroy_inodecache();
429}
430
431module_init(init_coda);
432module_exit(exit_coda);
433