Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * An implementation of a loadable kernel mode driver providing | |
3 | * multiple kernel/user space bidirectional communications links. | |
4 | * | |
5 | * Author: Alan Cox <alan@redhat.com> | |
6 | * | |
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> | |
1da177e4 LT |
31 | #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> | |
48 | #include <linux/coda_proc.h> | |
49 | ||
c98d8cfb | 50 | #include "coda_int.h" |
1da177e4 | 51 | |
c98d8cfb | 52 | #define upc_free(r) kfree(r) |
1da177e4 LT |
53 | |
54 | /* statistics */ | |
55 | int coda_hard; /* allows signals during upcalls */ | |
56 | unsigned long coda_timeout = 30; /* .. secs, then signals will dequeue */ | |
57 | ||
58 | ||
59 | struct venus_comm coda_comms[MAX_CODADEVS]; | |
1db560af | 60 | static struct class *coda_psdev_class; |
1da177e4 LT |
61 | |
62 | /* | |
63 | * Device operations | |
64 | */ | |
65 | ||
66 | static unsigned int coda_psdev_poll(struct file *file, poll_table * wait) | |
67 | { | |
68 | struct venus_comm *vcp = (struct venus_comm *) file->private_data; | |
69 | unsigned int mask = POLLOUT | POLLWRNORM; | |
70 | ||
71 | poll_wait(file, &vcp->vc_waitq, wait); | |
72 | if (!list_empty(&vcp->vc_pending)) | |
73 | mask |= POLLIN | POLLRDNORM; | |
74 | ||
75 | return mask; | |
76 | } | |
77 | ||
78 | static int coda_psdev_ioctl(struct inode * inode, struct file * filp, | |
79 | unsigned int cmd, unsigned long arg) | |
80 | { | |
81 | unsigned int data; | |
82 | ||
83 | switch(cmd) { | |
84 | case CIOC_KERNEL_VERSION: | |
85 | data = CODA_KERNEL_VERSION; | |
86 | return put_user(data, (int __user *) arg); | |
87 | default: | |
88 | return -ENOTTY; | |
89 | } | |
90 | ||
91 | return 0; | |
92 | } | |
93 | ||
94 | /* | |
95 | * Receive a message written by Venus to the psdev | |
96 | */ | |
97 | ||
98 | static ssize_t coda_psdev_write(struct file *file, const char __user *buf, | |
99 | size_t nbytes, loff_t *off) | |
100 | { | |
101 | struct venus_comm *vcp = (struct venus_comm *) file->private_data; | |
102 | struct upc_req *req = NULL; | |
103 | struct upc_req *tmp; | |
104 | struct list_head *lh; | |
105 | struct coda_in_hdr hdr; | |
106 | ssize_t retval = 0, count = 0; | |
107 | int error; | |
108 | ||
109 | /* Peek at the opcode, uniquefier */ | |
110 | if (copy_from_user(&hdr, buf, 2 * sizeof(u_long))) | |
111 | return -EFAULT; | |
112 | ||
113 | if (DOWNCALL(hdr.opcode)) { | |
114 | struct super_block *sb = NULL; | |
115 | union outputArgs *dcbuf; | |
116 | int size = sizeof(*dcbuf); | |
117 | ||
118 | sb = vcp->vc_sb; | |
119 | if ( !sb ) { | |
120 | count = nbytes; | |
121 | goto out; | |
122 | } | |
123 | ||
124 | if ( nbytes < sizeof(struct coda_out_hdr) ) { | |
125 | printk("coda_downcall opc %d uniq %d, not enough!\n", | |
126 | hdr.opcode, hdr.unique); | |
127 | count = nbytes; | |
128 | goto out; | |
129 | } | |
130 | if ( nbytes > size ) { | |
131 | printk("Coda: downcall opc %d, uniq %d, too much!", | |
132 | hdr.opcode, hdr.unique); | |
133 | nbytes = size; | |
134 | } | |
135 | CODA_ALLOC(dcbuf, union outputArgs *, nbytes); | |
136 | if (copy_from_user(dcbuf, buf, nbytes)) { | |
137 | CODA_FREE(dcbuf, nbytes); | |
138 | retval = -EFAULT; | |
139 | goto out; | |
140 | } | |
141 | ||
142 | /* what downcall errors does Venus handle ? */ | |
143 | lock_kernel(); | |
144 | error = coda_downcall(hdr.opcode, dcbuf, sb); | |
145 | unlock_kernel(); | |
146 | ||
147 | CODA_FREE(dcbuf, nbytes); | |
148 | if (error) { | |
149 | printk("psdev_write: coda_downcall error: %d\n", error); | |
150 | retval = error; | |
151 | goto out; | |
152 | } | |
153 | count = nbytes; | |
154 | goto out; | |
155 | } | |
156 | ||
157 | /* Look for the message on the processing queue. */ | |
158 | lock_kernel(); | |
159 | list_for_each(lh, &vcp->vc_processing) { | |
160 | tmp = list_entry(lh, struct upc_req , uc_chain); | |
161 | if (tmp->uc_unique == hdr.unique) { | |
162 | req = tmp; | |
163 | list_del(&req->uc_chain); | |
164 | break; | |
165 | } | |
166 | } | |
167 | unlock_kernel(); | |
168 | ||
169 | if (!req) { | |
170 | printk("psdev_write: msg (%d, %d) not found\n", | |
171 | hdr.opcode, hdr.unique); | |
172 | retval = -ESRCH; | |
173 | goto out; | |
174 | } | |
175 | ||
176 | /* move data into response buffer. */ | |
177 | if (req->uc_outSize < nbytes) { | |
178 | printk("psdev_write: too much cnt: %d, cnt: %ld, opc: %d, uniq: %d.\n", | |
179 | req->uc_outSize, (long)nbytes, hdr.opcode, hdr.unique); | |
180 | nbytes = req->uc_outSize; /* don't have more space! */ | |
181 | } | |
182 | if (copy_from_user(req->uc_data, buf, nbytes)) { | |
183 | req->uc_flags |= REQ_ABORT; | |
184 | wake_up(&req->uc_sleep); | |
185 | retval = -EFAULT; | |
186 | goto out; | |
187 | } | |
188 | ||
189 | /* adjust outsize. is this useful ?? */ | |
190 | req->uc_outSize = nbytes; | |
191 | req->uc_flags |= REQ_WRITE; | |
192 | count = nbytes; | |
193 | ||
194 | /* Convert filedescriptor into a file handle */ | |
195 | if (req->uc_opcode == CODA_OPEN_BY_FD) { | |
196 | struct coda_open_by_fd_out *outp = | |
197 | (struct coda_open_by_fd_out *)req->uc_data; | |
198 | outp->fh = fget(outp->fd); | |
199 | } | |
200 | ||
201 | wake_up(&req->uc_sleep); | |
202 | out: | |
203 | return(count ? count : retval); | |
204 | } | |
205 | ||
206 | /* | |
207 | * Read a message from the kernel to Venus | |
208 | */ | |
209 | ||
210 | static ssize_t coda_psdev_read(struct file * file, char __user * buf, | |
211 | size_t nbytes, loff_t *off) | |
212 | { | |
213 | DECLARE_WAITQUEUE(wait, current); | |
214 | struct venus_comm *vcp = (struct venus_comm *) file->private_data; | |
215 | struct upc_req *req; | |
216 | ssize_t retval = 0, count = 0; | |
217 | ||
218 | if (nbytes == 0) | |
219 | return 0; | |
220 | ||
221 | lock_kernel(); | |
222 | ||
223 | add_wait_queue(&vcp->vc_waitq, &wait); | |
224 | set_current_state(TASK_INTERRUPTIBLE); | |
225 | ||
226 | while (list_empty(&vcp->vc_pending)) { | |
227 | if (file->f_flags & O_NONBLOCK) { | |
228 | retval = -EAGAIN; | |
229 | break; | |
230 | } | |
231 | if (signal_pending(current)) { | |
232 | retval = -ERESTARTSYS; | |
233 | break; | |
234 | } | |
235 | schedule(); | |
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) { | |
250 | printk ("psdev_read: Venus read %ld bytes of %d in message\n", | |
251 | (long)nbytes, req->uc_inSize); | |
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 */ | |
259 | if (!(req->uc_flags & REQ_ASYNC)) { | |
260 | req->uc_flags |= REQ_READ; | |
8e13059a | 261 | list_add_tail(&(req->uc_chain), &vcp->vc_processing); |
1da177e4 LT |
262 | goto out; |
263 | } | |
264 | ||
265 | CODA_FREE(req->uc_data, sizeof(struct coda_in_hdr)); | |
266 | upc_free(req); | |
267 | out: | |
268 | unlock_kernel(); | |
269 | return (count ? count : retval); | |
270 | } | |
271 | ||
272 | static int coda_psdev_open(struct inode * inode, struct file * file) | |
273 | { | |
274 | struct venus_comm *vcp; | |
275 | int idx; | |
276 | ||
277 | lock_kernel(); | |
278 | idx = iminor(inode); | |
279 | if(idx >= MAX_CODADEVS) { | |
280 | unlock_kernel(); | |
281 | return -ENODEV; | |
282 | } | |
283 | ||
284 | vcp = &coda_comms[idx]; | |
285 | if(vcp->vc_inuse) { | |
286 | unlock_kernel(); | |
287 | return -EBUSY; | |
288 | } | |
289 | ||
290 | if (!vcp->vc_inuse++) { | |
291 | INIT_LIST_HEAD(&vcp->vc_pending); | |
292 | INIT_LIST_HEAD(&vcp->vc_processing); | |
293 | init_waitqueue_head(&vcp->vc_waitq); | |
294 | vcp->vc_sb = NULL; | |
295 | vcp->vc_seq = 0; | |
296 | } | |
297 | ||
298 | file->private_data = vcp; | |
299 | ||
300 | unlock_kernel(); | |
301 | return 0; | |
302 | } | |
303 | ||
304 | ||
305 | static int coda_psdev_release(struct inode * inode, struct file * file) | |
306 | { | |
307 | struct venus_comm *vcp = (struct venus_comm *) file->private_data; | |
308 | struct upc_req *req, *tmp; | |
309 | ||
310 | lock_kernel(); | |
311 | if ( !vcp->vc_inuse ) { | |
312 | unlock_kernel(); | |
313 | printk("psdev_release: Not open.\n"); | |
314 | return -1; | |
315 | } | |
316 | ||
317 | if (--vcp->vc_inuse) { | |
318 | unlock_kernel(); | |
319 | return 0; | |
320 | } | |
321 | ||
322 | /* Wakeup clients so they can return. */ | |
323 | list_for_each_entry_safe(req, tmp, &vcp->vc_pending, uc_chain) { | |
324 | /* Async requests need to be freed here */ | |
325 | if (req->uc_flags & REQ_ASYNC) { | |
326 | CODA_FREE(req->uc_data, sizeof(struct coda_in_hdr)); | |
327 | upc_free(req); | |
328 | continue; | |
329 | } | |
330 | req->uc_flags |= REQ_ABORT; | |
331 | wake_up(&req->uc_sleep); | |
332 | } | |
333 | ||
334 | list_for_each_entry(req, &vcp->vc_processing, uc_chain) { | |
335 | req->uc_flags |= REQ_ABORT; | |
336 | wake_up(&req->uc_sleep); | |
337 | } | |
338 | ||
339 | unlock_kernel(); | |
340 | return 0; | |
341 | } | |
342 | ||
343 | ||
4b6f5d20 | 344 | static const struct file_operations coda_psdev_fops = { |
1da177e4 LT |
345 | .owner = THIS_MODULE, |
346 | .read = coda_psdev_read, | |
347 | .write = coda_psdev_write, | |
348 | .poll = coda_psdev_poll, | |
349 | .ioctl = coda_psdev_ioctl, | |
350 | .open = coda_psdev_open, | |
351 | .release = coda_psdev_release, | |
352 | }; | |
353 | ||
354 | static int init_coda_psdev(void) | |
355 | { | |
356 | int i, err = 0; | |
357 | if (register_chrdev(CODA_PSDEV_MAJOR, "coda", &coda_psdev_fops)) { | |
358 | printk(KERN_ERR "coda_psdev: unable to get major %d\n", | |
359 | CODA_PSDEV_MAJOR); | |
360 | return -EIO; | |
361 | } | |
1db560af | 362 | coda_psdev_class = class_create(THIS_MODULE, "coda"); |
1da177e4 LT |
363 | if (IS_ERR(coda_psdev_class)) { |
364 | err = PTR_ERR(coda_psdev_class); | |
365 | goto out_chrdev; | |
366 | } | |
7c69ef79 | 367 | for (i = 0; i < MAX_CODADEVS; i++) |
53f46542 GKH |
368 | class_device_create(coda_psdev_class, NULL, |
369 | MKDEV(CODA_PSDEV_MAJOR,i), NULL, "cfs%d", i); | |
1da177e4 LT |
370 | coda_sysctl_init(); |
371 | goto out; | |
372 | ||
1da177e4 LT |
373 | out_chrdev: |
374 | unregister_chrdev(CODA_PSDEV_MAJOR, "coda"); | |
375 | out: | |
376 | return err; | |
377 | } | |
378 | ||
379 | ||
380 | MODULE_AUTHOR("Peter J. Braam <braam@cs.cmu.edu>"); | |
381 | MODULE_LICENSE("GPL"); | |
382 | ||
1da177e4 LT |
383 | static int __init init_coda(void) |
384 | { | |
385 | int status; | |
386 | int i; | |
387 | printk(KERN_INFO "Coda Kernel/Venus communications, " | |
388 | #ifdef CONFIG_CODA_FS_OLD_API | |
389 | "v5.3.20" | |
390 | #else | |
391 | "v6.0.0" | |
392 | #endif | |
393 | ", coda@cs.cmu.edu\n"); | |
394 | ||
395 | status = coda_init_inodecache(); | |
396 | if (status) | |
397 | goto out2; | |
398 | status = init_coda_psdev(); | |
399 | if ( status ) { | |
400 | printk("Problem (%d) in init_coda_psdev\n", status); | |
401 | goto out1; | |
402 | } | |
403 | ||
404 | status = register_filesystem(&coda_fs_type); | |
405 | if (status) { | |
406 | printk("coda: failed to register filesystem!\n"); | |
407 | goto out; | |
408 | } | |
409 | return 0; | |
410 | out: | |
8ab5e4c1 | 411 | for (i = 0; i < MAX_CODADEVS; i++) |
1db560af | 412 | class_device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i)); |
1db560af | 413 | class_destroy(coda_psdev_class); |
1da177e4 LT |
414 | unregister_chrdev(CODA_PSDEV_MAJOR, "coda"); |
415 | coda_sysctl_clean(); | |
416 | out1: | |
417 | coda_destroy_inodecache(); | |
418 | out2: | |
419 | return status; | |
420 | } | |
421 | ||
422 | static void __exit exit_coda(void) | |
423 | { | |
424 | int err, i; | |
425 | ||
426 | err = unregister_filesystem(&coda_fs_type); | |
427 | if ( err != 0 ) { | |
428 | printk("coda: failed to unregister filesystem\n"); | |
429 | } | |
8ab5e4c1 | 430 | for (i = 0; i < MAX_CODADEVS; i++) |
1db560af | 431 | class_device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i)); |
1db560af | 432 | class_destroy(coda_psdev_class); |
1da177e4 LT |
433 | unregister_chrdev(CODA_PSDEV_MAJOR, "coda"); |
434 | coda_sysctl_clean(); | |
435 | coda_destroy_inodecache(); | |
436 | } | |
437 | ||
438 | module_init(init_coda); | |
439 | module_exit(exit_coda); | |
440 |