blob: 761d5b31b18d0b27ce83d6d7ed7a815d3e63b75d [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>
Yoshihisa Abeda47c192010-10-25 02:03:46 -040038#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#include <linux/device.h>
40#include <asm/io.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070041#include <asm/poll.h>
42#include <asm/uaccess.h>
43
44#include <linux/coda.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070045#include <linux/coda_psdev.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
Al Viro31a203d2011-01-12 16:36:09 -050047#include "coda_linux.h"
48
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);
Yoshihisa Abeda47c192010-10-25 02:03:46 -040069 mutex_lock(&vcp->vc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 if (!list_empty(&vcp->vc_pending))
71 mask |= POLLIN | POLLRDNORM;
Yoshihisa Abeda47c192010-10-25 02:03:46 -040072 mutex_unlock(&vcp->vc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
74 return mask;
75}
76
Arnd Bergmann97718392010-04-27 16:24:24 +020077static long coda_psdev_ioctl(struct file * filp, unsigned int cmd, unsigned long arg)
Linus Torvalds1da177e2005-04-16 15:20:36 -070078{
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)) {
Yoshihisa Abef7cc02b82010-10-25 02:03:45 -0400112 union outputArgs *dcbuf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113 int size = sizeof(*dcbuf);
114
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 if ( nbytes < sizeof(struct coda_out_hdr) ) {
116 printk("coda_downcall opc %d uniq %d, not enough!\n",
117 hdr.opcode, hdr.unique);
118 count = nbytes;
119 goto out;
120 }
121 if ( nbytes > size ) {
122 printk("Coda: downcall opc %d, uniq %d, too much!",
123 hdr.opcode, hdr.unique);
124 nbytes = size;
125 }
126 CODA_ALLOC(dcbuf, union outputArgs *, nbytes);
127 if (copy_from_user(dcbuf, buf, nbytes)) {
128 CODA_FREE(dcbuf, nbytes);
129 retval = -EFAULT;
130 goto out;
131 }
132
133 /* what downcall errors does Venus handle ? */
Yoshihisa Abef7cc02b82010-10-25 02:03:45 -0400134 error = coda_downcall(vcp, hdr.opcode, dcbuf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135
136 CODA_FREE(dcbuf, nbytes);
137 if (error) {
138 printk("psdev_write: coda_downcall error: %d\n", error);
139 retval = error;
140 goto out;
141 }
142 count = nbytes;
143 goto out;
144 }
145
146 /* Look for the message on the processing queue. */
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400147 mutex_lock(&vcp->vc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148 list_for_each(lh, &vcp->vc_processing) {
149 tmp = list_entry(lh, struct upc_req , uc_chain);
150 if (tmp->uc_unique == hdr.unique) {
151 req = tmp;
152 list_del(&req->uc_chain);
153 break;
154 }
155 }
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400156 mutex_unlock(&vcp->vc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157
158 if (!req) {
159 printk("psdev_write: msg (%d, %d) not found\n",
160 hdr.opcode, hdr.unique);
161 retval = -ESRCH;
162 goto out;
163 }
164
165 /* move data into response buffer. */
166 if (req->uc_outSize < nbytes) {
167 printk("psdev_write: too much cnt: %d, cnt: %ld, opc: %d, uniq: %d.\n",
168 req->uc_outSize, (long)nbytes, hdr.opcode, hdr.unique);
169 nbytes = req->uc_outSize; /* don't have more space! */
170 }
171 if (copy_from_user(req->uc_data, buf, nbytes)) {
Jens Axboe4aeefdc2010-08-03 13:22:51 +0200172 req->uc_flags |= CODA_REQ_ABORT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 wake_up(&req->uc_sleep);
174 retval = -EFAULT;
175 goto out;
176 }
177
178 /* adjust outsize. is this useful ?? */
Jan Harkes112d4212010-09-17 23:26:01 -0400179 req->uc_outSize = nbytes;
180 req->uc_flags |= CODA_REQ_WRITE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 count = nbytes;
182
183 /* Convert filedescriptor into a file handle */
184 if (req->uc_opcode == CODA_OPEN_BY_FD) {
185 struct coda_open_by_fd_out *outp =
186 (struct coda_open_by_fd_out *)req->uc_data;
Jan Harkes38c2e432007-07-19 01:48:41 -0700187 if (!outp->oh.result)
188 outp->fh = fget(outp->fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 }
190
191 wake_up(&req->uc_sleep);
192out:
193 return(count ? count : retval);
194}
195
196/*
197 * Read a message from the kernel to Venus
198 */
199
200static ssize_t coda_psdev_read(struct file * file, char __user * buf,
201 size_t nbytes, loff_t *off)
202{
203 DECLARE_WAITQUEUE(wait, current);
204 struct venus_comm *vcp = (struct venus_comm *) file->private_data;
205 struct upc_req *req;
206 ssize_t retval = 0, count = 0;
207
208 if (nbytes == 0)
209 return 0;
210
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400211 mutex_lock(&vcp->vc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212
213 add_wait_queue(&vcp->vc_waitq, &wait);
214 set_current_state(TASK_INTERRUPTIBLE);
215
216 while (list_empty(&vcp->vc_pending)) {
217 if (file->f_flags & O_NONBLOCK) {
218 retval = -EAGAIN;
219 break;
220 }
221 if (signal_pending(current)) {
222 retval = -ERESTARTSYS;
223 break;
224 }
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400225 mutex_unlock(&vcp->vc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 schedule();
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400227 mutex_lock(&vcp->vc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228 }
229
230 set_current_state(TASK_RUNNING);
231 remove_wait_queue(&vcp->vc_waitq, &wait);
232
233 if (retval)
234 goto out;
235
236 req = list_entry(vcp->vc_pending.next, struct upc_req,uc_chain);
237 list_del(&req->uc_chain);
238
239 /* Move the input args into userspace */
240 count = req->uc_inSize;
241 if (nbytes < req->uc_inSize) {
242 printk ("psdev_read: Venus read %ld bytes of %d in message\n",
243 (long)nbytes, req->uc_inSize);
244 count = nbytes;
245 }
246
247 if (copy_to_user(buf, req->uc_data, count))
248 retval = -EFAULT;
249
250 /* If request was not a signal, enqueue and don't free */
Jens Axboe4aeefdc2010-08-03 13:22:51 +0200251 if (!(req->uc_flags & CODA_REQ_ASYNC)) {
252 req->uc_flags |= CODA_REQ_READ;
Akinobu Mita8e130592006-06-26 00:24:37 -0700253 list_add_tail(&(req->uc_chain), &vcp->vc_processing);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 goto out;
255 }
256
257 CODA_FREE(req->uc_data, sizeof(struct coda_in_hdr));
Jan Harkes37461e12007-07-19 01:48:48 -0700258 kfree(req);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259out:
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400260 mutex_unlock(&vcp->vc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 return (count ? count : retval);
262}
263
264static int coda_psdev_open(struct inode * inode, struct file * file)
265{
Jan Harkes87065512007-07-19 01:48:45 -0700266 struct venus_comm *vcp;
267 int idx, err;
268
269 idx = iminor(inode);
270 if (idx < 0 || idx >= MAX_CODADEVS)
271 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272
Jan Harkes87065512007-07-19 01:48:45 -0700273 err = -EBUSY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 vcp = &coda_comms[idx];
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400275 mutex_lock(&vcp->vc_mutex);
276
Jan Harkes87065512007-07-19 01:48:45 -0700277 if (!vcp->vc_inuse) {
278 vcp->vc_inuse++;
279
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 INIT_LIST_HEAD(&vcp->vc_pending);
281 INIT_LIST_HEAD(&vcp->vc_processing);
282 init_waitqueue_head(&vcp->vc_waitq);
283 vcp->vc_sb = NULL;
284 vcp->vc_seq = 0;
Jan Harkes87065512007-07-19 01:48:45 -0700285
286 file->private_data = vcp;
287 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400290 mutex_unlock(&vcp->vc_mutex);
Jan Harkes87065512007-07-19 01:48:45 -0700291 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292}
293
294
295static int coda_psdev_release(struct inode * inode, struct file * file)
296{
Jan Harkes87065512007-07-19 01:48:45 -0700297 struct venus_comm *vcp = (struct venus_comm *) file->private_data;
298 struct upc_req *req, *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299
Jan Harkes87065512007-07-19 01:48:45 -0700300 if (!vcp || !vcp->vc_inuse ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 printk("psdev_release: Not open.\n");
302 return -1;
303 }
304
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400305 mutex_lock(&vcp->vc_mutex);
Jan Harkes87065512007-07-19 01:48:45 -0700306
307 /* Wakeup clients so they can return. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308 list_for_each_entry_safe(req, tmp, &vcp->vc_pending, uc_chain) {
Jan Harkes87065512007-07-19 01:48:45 -0700309 list_del(&req->uc_chain);
310
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 /* Async requests need to be freed here */
Jens Axboe4aeefdc2010-08-03 13:22:51 +0200312 if (req->uc_flags & CODA_REQ_ASYNC) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 CODA_FREE(req->uc_data, sizeof(struct coda_in_hdr));
Jan Harkes37461e12007-07-19 01:48:48 -0700314 kfree(req);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315 continue;
316 }
Jens Axboe4aeefdc2010-08-03 13:22:51 +0200317 req->uc_flags |= CODA_REQ_ABORT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318 wake_up(&req->uc_sleep);
Jan Harkes87065512007-07-19 01:48:45 -0700319 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320
Jan Harkes87065512007-07-19 01:48:45 -0700321 list_for_each_entry_safe(req, tmp, &vcp->vc_processing, uc_chain) {
322 list_del(&req->uc_chain);
323
Jens Axboe4aeefdc2010-08-03 13:22:51 +0200324 req->uc_flags |= CODA_REQ_ABORT;
Jan Harkes87065512007-07-19 01:48:45 -0700325 wake_up(&req->uc_sleep);
326 }
327
328 file->private_data = NULL;
329 vcp->vc_inuse--;
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400330 mutex_unlock(&vcp->vc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 return 0;
332}
333
334
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800335static const struct file_operations coda_psdev_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 .owner = THIS_MODULE,
337 .read = coda_psdev_read,
338 .write = coda_psdev_write,
339 .poll = coda_psdev_poll,
Arnd Bergmann97718392010-04-27 16:24:24 +0200340 .unlocked_ioctl = coda_psdev_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 .open = coda_psdev_open,
342 .release = coda_psdev_release,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200343 .llseek = noop_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344};
345
346static int init_coda_psdev(void)
347{
348 int i, err = 0;
349 if (register_chrdev(CODA_PSDEV_MAJOR, "coda", &coda_psdev_fops)) {
350 printk(KERN_ERR "coda_psdev: unable to get major %d\n",
351 CODA_PSDEV_MAJOR);
352 return -EIO;
353 }
gregkh@suse.de1db560a2005-03-23 10:02:26 -0800354 coda_psdev_class = class_create(THIS_MODULE, "coda");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 if (IS_ERR(coda_psdev_class)) {
356 err = PTR_ERR(coda_psdev_class);
357 goto out_chrdev;
358 }
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400359 for (i = 0; i < MAX_CODADEVS; i++) {
360 mutex_init(&(&coda_comms[i])->vc_mutex);
Greg Kroah-Hartmana9b12612008-07-21 20:03:34 -0700361 device_create(coda_psdev_class, NULL,
362 MKDEV(CODA_PSDEV_MAJOR, i), NULL, "cfs%d", i);
Yoshihisa Abeda47c192010-10-25 02:03:46 -0400363 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 coda_sysctl_init();
365 goto out;
366
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367out_chrdev:
368 unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
369out:
370 return err;
371}
372
Jan Harkes5b7f13b2007-07-19 01:48:52 -0700373MODULE_AUTHOR("Jan Harkes, Peter J. Braam");
374MODULE_DESCRIPTION("Coda Distributed File System VFS interface");
375MODULE_ALIAS_CHARDEV_MAJOR(CODA_PSDEV_MAJOR);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376MODULE_LICENSE("GPL");
Jan Harkes5b7f13b2007-07-19 01:48:52 -0700377MODULE_VERSION("6.6");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379static int __init init_coda(void)
380{
381 int status;
382 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383
384 status = coda_init_inodecache();
385 if (status)
386 goto out2;
387 status = init_coda_psdev();
388 if ( status ) {
389 printk("Problem (%d) in init_coda_psdev\n", status);
390 goto out1;
391 }
392
393 status = register_filesystem(&coda_fs_type);
394 if (status) {
395 printk("coda: failed to register filesystem!\n");
396 goto out;
397 }
398 return 0;
399out:
Greg Kroah-Hartman8ab5e4c2005-06-20 21:15:16 -0700400 for (i = 0; i < MAX_CODADEVS; i++)
Kay Sievers62ca8792007-09-25 02:03:03 +0200401 device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
gregkh@suse.de1db560a2005-03-23 10:02:26 -0800402 class_destroy(coda_psdev_class);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
404 coda_sysctl_clean();
405out1:
406 coda_destroy_inodecache();
407out2:
408 return status;
409}
410
411static void __exit exit_coda(void)
412{
413 int err, i;
414
415 err = unregister_filesystem(&coda_fs_type);
416 if ( err != 0 ) {
417 printk("coda: failed to unregister filesystem\n");
418 }
Greg Kroah-Hartman8ab5e4c2005-06-20 21:15:16 -0700419 for (i = 0; i < MAX_CODADEVS; i++)
Kay Sievers62ca8792007-09-25 02:03:03 +0200420 device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i));
gregkh@suse.de1db560a2005-03-23 10:02:26 -0800421 class_destroy(coda_psdev_class);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422 unregister_chrdev(CODA_PSDEV_MAJOR, "coda");
423 coda_sysctl_clean();
424 coda_destroy_inodecache();
425}
426
427module_init(init_coda);
428module_exit(exit_coda);
429