GNU Linux-libre 4.19.211-gnu1
[releases.git] / fs / orangefs / devorangefs-req.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * (C) 2001 Clemson University and The University of Chicago
4  *
5  * Changes by Acxiom Corporation to add protocol version to kernel
6  * communication, Copyright Acxiom Corporation, 2005.
7  *
8  * See COPYING in top-level directory.
9  */
10
11 #include "protocol.h"
12 #include "orangefs-kernel.h"
13 #include "orangefs-dev-proto.h"
14 #include "orangefs-bufmap.h"
15 #include "orangefs-debugfs.h"
16
17 #include <linux/debugfs.h>
18 #include <linux/slab.h>
19
20 /* this file implements the /dev/pvfs2-req device node */
21
22 uint32_t orangefs_userspace_version;
23
24 static int open_access_count;
25
26 static DEFINE_MUTEX(devreq_mutex);
27
28 #define DUMP_DEVICE_ERROR()                                                   \
29 do {                                                                          \
30         gossip_err("*****************************************************\n");\
31         gossip_err("ORANGEFS Device Error:  You cannot open the device file ");  \
32         gossip_err("\n/dev/%s more than once.  Please make sure that\nthere " \
33                    "are no ", ORANGEFS_REQDEVICE_NAME);                          \
34         gossip_err("instances of a program using this device\ncurrently "     \
35                    "running. (You must verify this!)\n");                     \
36         gossip_err("For example, you can use the lsof program as follows:\n");\
37         gossip_err("'lsof | grep %s' (run this as root)\n",                   \
38                    ORANGEFS_REQDEVICE_NAME);                                     \
39         gossip_err("  open_access_count = %d\n", open_access_count);          \
40         gossip_err("*****************************************************\n");\
41 } while (0)
42
43 static int hash_func(__u64 tag, int table_size)
44 {
45         return do_div(tag, (unsigned int)table_size);
46 }
47
48 static void orangefs_devreq_add_op(struct orangefs_kernel_op_s *op)
49 {
50         int index = hash_func(op->tag, hash_table_size);
51
52         list_add_tail(&op->list, &orangefs_htable_ops_in_progress[index]);
53 }
54
55 /*
56  * find the op with this tag and remove it from the in progress
57  * hash table.
58  */
59 static struct orangefs_kernel_op_s *orangefs_devreq_remove_op(__u64 tag)
60 {
61         struct orangefs_kernel_op_s *op, *next;
62         int index;
63
64         index = hash_func(tag, hash_table_size);
65
66         spin_lock(&orangefs_htable_ops_in_progress_lock);
67         list_for_each_entry_safe(op,
68                                  next,
69                                  &orangefs_htable_ops_in_progress[index],
70                                  list) {
71                 if (op->tag == tag && !op_state_purged(op) &&
72                     !op_state_given_up(op)) {
73                         list_del_init(&op->list);
74                         spin_unlock(&orangefs_htable_ops_in_progress_lock);
75                         return op;
76                 }
77         }
78
79         spin_unlock(&orangefs_htable_ops_in_progress_lock);
80         return NULL;
81 }
82
83 /* Returns whether any FS are still pending remounted */
84 static int mark_all_pending_mounts(void)
85 {
86         int unmounted = 1;
87         struct orangefs_sb_info_s *orangefs_sb = NULL;
88
89         spin_lock(&orangefs_superblocks_lock);
90         list_for_each_entry(orangefs_sb, &orangefs_superblocks, list) {
91                 /* All of these file system require a remount */
92                 orangefs_sb->mount_pending = 1;
93                 unmounted = 0;
94         }
95         spin_unlock(&orangefs_superblocks_lock);
96         return unmounted;
97 }
98
99 /*
100  * Determine if a given file system needs to be remounted or not
101  *  Returns -1 on error
102  *           0 if already mounted
103  *           1 if needs remount
104  */
105 static int fs_mount_pending(__s32 fsid)
106 {
107         int mount_pending = -1;
108         struct orangefs_sb_info_s *orangefs_sb = NULL;
109
110         spin_lock(&orangefs_superblocks_lock);
111         list_for_each_entry(orangefs_sb, &orangefs_superblocks, list) {
112                 if (orangefs_sb->fs_id == fsid) {
113                         mount_pending = orangefs_sb->mount_pending;
114                         break;
115                 }
116         }
117         spin_unlock(&orangefs_superblocks_lock);
118         return mount_pending;
119 }
120
121 static int orangefs_devreq_open(struct inode *inode, struct file *file)
122 {
123         int ret = -EINVAL;
124
125         /* in order to ensure that the filesystem driver sees correct UIDs */
126         if (file->f_cred->user_ns != &init_user_ns) {
127                 gossip_err("%s: device cannot be opened outside init_user_ns\n",
128                            __func__);
129                 goto out;
130         }
131
132         if (!(file->f_flags & O_NONBLOCK)) {
133                 gossip_err("%s: device cannot be opened in blocking mode\n",
134                            __func__);
135                 goto out;
136         }
137         ret = -EACCES;
138         gossip_debug(GOSSIP_DEV_DEBUG, "client-core: opening device\n");
139         mutex_lock(&devreq_mutex);
140
141         if (open_access_count == 0) {
142                 open_access_count = 1;
143                 ret = 0;
144         } else {
145                 DUMP_DEVICE_ERROR();
146         }
147         mutex_unlock(&devreq_mutex);
148
149 out:
150
151         gossip_debug(GOSSIP_DEV_DEBUG,
152                      "pvfs2-client-core: open device complete (ret = %d)\n",
153                      ret);
154         return ret;
155 }
156
157 /* Function for read() callers into the device */
158 static ssize_t orangefs_devreq_read(struct file *file,
159                                  char __user *buf,
160                                  size_t count, loff_t *offset)
161 {
162         struct orangefs_kernel_op_s *op, *temp;
163         __s32 proto_ver = ORANGEFS_KERNEL_PROTO_VERSION;
164         static __s32 magic = ORANGEFS_DEVREQ_MAGIC;
165         struct orangefs_kernel_op_s *cur_op;
166         unsigned long ret;
167
168         /* We do not support blocking IO. */
169         if (!(file->f_flags & O_NONBLOCK)) {
170                 gossip_err("%s: blocking read from client-core.\n",
171                            __func__);
172                 return -EINVAL;
173         }
174
175         /*
176          * The client will do an ioctl to find MAX_DEV_REQ_UPSIZE, then
177          * always read with that size buffer.
178          */
179         if (count != MAX_DEV_REQ_UPSIZE) {
180                 gossip_err("orangefs: client-core tried to read wrong size\n");
181                 return -EINVAL;
182         }
183
184         /* Check for an empty list before locking. */
185         if (list_empty(&orangefs_request_list))
186                 return -EAGAIN;
187
188 restart:
189         cur_op = NULL;
190         /* Get next op (if any) from top of list. */
191         spin_lock(&orangefs_request_list_lock);
192         list_for_each_entry_safe(op, temp, &orangefs_request_list, list) {
193                 __s32 fsid;
194                 /* This lock is held past the end of the loop when we break. */
195                 spin_lock(&op->lock);
196                 if (unlikely(op_state_purged(op) || op_state_given_up(op))) {
197                         spin_unlock(&op->lock);
198                         continue;
199                 }
200
201                 fsid = fsid_of_op(op);
202                 if (fsid != ORANGEFS_FS_ID_NULL) {
203                         int ret;
204                         /* Skip ops whose filesystem needs to be mounted. */
205                         ret = fs_mount_pending(fsid);
206                         if (ret == 1) {
207                                 gossip_debug(GOSSIP_DEV_DEBUG,
208                                     "%s: mount pending, skipping op tag "
209                                     "%llu %s\n",
210                                     __func__,
211                                     llu(op->tag),
212                                     get_opname_string(op));
213                                 spin_unlock(&op->lock);
214                                 continue;
215                         /*
216                          * Skip ops whose filesystem we don't know about unless
217                          * it is being mounted or unmounted.  It is possible for
218                          * a filesystem we don't know about to be unmounted if
219                          * it fails to mount in the kernel after userspace has
220                          * been sent the mount request.
221                          */
222                         /* XXX: is there a better way to detect this? */
223                         } else if (ret == -1 &&
224                                    !(op->upcall.type ==
225                                         ORANGEFS_VFS_OP_FS_MOUNT ||
226                                      op->upcall.type ==
227                                         ORANGEFS_VFS_OP_GETATTR ||
228                                      op->upcall.type ==
229                                         ORANGEFS_VFS_OP_FS_UMOUNT)) {
230                                 gossip_debug(GOSSIP_DEV_DEBUG,
231                                     "orangefs: skipping op tag %llu %s\n",
232                                     llu(op->tag), get_opname_string(op));
233                                 gossip_err(
234                                     "orangefs: ERROR: fs_mount_pending %d\n",
235                                     fsid);
236                                 spin_unlock(&op->lock);
237                                 continue;
238                         }
239                 }
240                 /*
241                  * Either this op does not pertain to a filesystem, is mounting
242                  * a filesystem, or pertains to a mounted filesystem. Let it
243                  * through.
244                  */
245                 cur_op = op;
246                 break;
247         }
248
249         /*
250          * At this point we either have a valid op and can continue or have not
251          * found an op and must ask the client to try again later.
252          */
253         if (!cur_op) {
254                 spin_unlock(&orangefs_request_list_lock);
255                 return -EAGAIN;
256         }
257
258         gossip_debug(GOSSIP_DEV_DEBUG, "%s: reading op tag %llu %s\n",
259                      __func__,
260                      llu(cur_op->tag),
261                      get_opname_string(cur_op));
262
263         /*
264          * Such an op should never be on the list in the first place. If so, we
265          * will abort.
266          */
267         if (op_state_in_progress(cur_op) || op_state_serviced(cur_op)) {
268                 gossip_err("orangefs: ERROR: Current op already queued.\n");
269                 list_del_init(&cur_op->list);
270                 spin_unlock(&cur_op->lock);
271                 spin_unlock(&orangefs_request_list_lock);
272                 return -EAGAIN;
273         }
274
275         list_del_init(&cur_op->list);
276         spin_unlock(&orangefs_request_list_lock);
277
278         spin_unlock(&cur_op->lock);
279
280         /* Push the upcall out. */
281         ret = copy_to_user(buf, &proto_ver, sizeof(__s32));
282         if (ret != 0)
283                 goto error;
284         ret = copy_to_user(buf + sizeof(__s32), &magic, sizeof(__s32));
285         if (ret != 0)
286                 goto error;
287         ret = copy_to_user(buf + 2 * sizeof(__s32),
288                 &cur_op->tag,
289                 sizeof(__u64));
290         if (ret != 0)
291                 goto error;
292         ret = copy_to_user(buf + 2 * sizeof(__s32) + sizeof(__u64),
293                 &cur_op->upcall,
294                 sizeof(struct orangefs_upcall_s));
295         if (ret != 0)
296                 goto error;
297
298         spin_lock(&orangefs_htable_ops_in_progress_lock);
299         spin_lock(&cur_op->lock);
300         if (unlikely(op_state_given_up(cur_op))) {
301                 spin_unlock(&cur_op->lock);
302                 spin_unlock(&orangefs_htable_ops_in_progress_lock);
303                 complete(&cur_op->waitq);
304                 goto restart;
305         }
306
307         /*
308          * Set the operation to be in progress and move it between lists since
309          * it has been sent to the client.
310          */
311         set_op_state_inprogress(cur_op);
312         gossip_debug(GOSSIP_DEV_DEBUG,
313                      "%s: 1 op:%s: op_state:%d: process:%s:\n",
314                      __func__,
315                      get_opname_string(cur_op),
316                      cur_op->op_state,
317                      current->comm);
318         orangefs_devreq_add_op(cur_op);
319         spin_unlock(&cur_op->lock);
320         spin_unlock(&orangefs_htable_ops_in_progress_lock);
321
322         /* The client only asks to read one size buffer. */
323         return MAX_DEV_REQ_UPSIZE;
324 error:
325         /*
326          * We were unable to copy the op data to the client. Put the op back in
327          * list. If client has crashed, the op will be purged later when the
328          * device is released.
329          */
330         gossip_err("orangefs: Failed to copy data to user space\n");
331         spin_lock(&orangefs_request_list_lock);
332         spin_lock(&cur_op->lock);
333         if (likely(!op_state_given_up(cur_op))) {
334                 set_op_state_waiting(cur_op);
335                 gossip_debug(GOSSIP_DEV_DEBUG,
336                              "%s: 2 op:%s: op_state:%d: process:%s:\n",
337                              __func__,
338                              get_opname_string(cur_op),
339                              cur_op->op_state,
340                              current->comm);
341                 list_add(&cur_op->list, &orangefs_request_list);
342                 spin_unlock(&cur_op->lock);
343         } else {
344                 spin_unlock(&cur_op->lock);
345                 complete(&cur_op->waitq);
346         }
347         spin_unlock(&orangefs_request_list_lock);
348         return -EFAULT;
349 }
350
351 /*
352  * Function for writev() callers into the device.
353  *
354  * Userspace should have written:
355  *  - __u32 version
356  *  - __u32 magic
357  *  - __u64 tag
358  *  - struct orangefs_downcall_s
359  *  - trailer buffer (in the case of READDIR operations)
360  */
361 static ssize_t orangefs_devreq_write_iter(struct kiocb *iocb,
362                                       struct iov_iter *iter)
363 {
364         ssize_t ret;
365         struct orangefs_kernel_op_s *op = NULL;
366         struct {
367                 __u32 version;
368                 __u32 magic;
369                 __u64 tag;
370         } head;
371         int total = ret = iov_iter_count(iter);
372         int downcall_size = sizeof(struct orangefs_downcall_s);
373         int head_size = sizeof(head);
374
375         gossip_debug(GOSSIP_DEV_DEBUG, "%s: total:%d: ret:%zd:\n",
376                      __func__,
377                      total,
378                      ret);
379
380         if (total < MAX_DEV_REQ_DOWNSIZE) {
381                 gossip_err("%s: total:%d: must be at least:%u:\n",
382                            __func__,
383                            total,
384                            (unsigned int) MAX_DEV_REQ_DOWNSIZE);
385                 return -EFAULT;
386         }
387
388         if (!copy_from_iter_full(&head, head_size, iter)) {
389                 gossip_err("%s: failed to copy head.\n", __func__);
390                 return -EFAULT;
391         }
392
393         if (head.version < ORANGEFS_MINIMUM_USERSPACE_VERSION) {
394                 gossip_err("%s: userspace claims version"
395                            "%d, minimum version required: %d.\n",
396                            __func__,
397                            head.version,
398                            ORANGEFS_MINIMUM_USERSPACE_VERSION);
399                 return -EPROTO;
400         }
401
402         if (head.magic != ORANGEFS_DEVREQ_MAGIC) {
403                 gossip_err("Error: Device magic number does not match.\n");
404                 return -EPROTO;
405         }
406
407         if (!orangefs_userspace_version) {
408                 orangefs_userspace_version = head.version;
409         } else if (orangefs_userspace_version != head.version) {
410                 gossip_err("Error: userspace version changes\n");
411                 return -EPROTO;
412         }
413
414         /* remove the op from the in progress hash table */
415         op = orangefs_devreq_remove_op(head.tag);
416         if (!op) {
417                 gossip_debug(GOSSIP_DEV_DEBUG,
418                              "%s: No one's waiting for tag %llu\n",
419                              __func__, llu(head.tag));
420                 return ret;
421         }
422
423         if (!copy_from_iter_full(&op->downcall, downcall_size, iter)) {
424                 gossip_err("%s: failed to copy downcall.\n", __func__);
425                 goto Efault;
426         }
427
428         if (op->downcall.status)
429                 goto wakeup;
430
431         /*
432          * We've successfully peeled off the head and the downcall.
433          * Something has gone awry if total doesn't equal the
434          * sum of head_size, downcall_size and trailer_size.
435          */
436         if ((head_size + downcall_size + op->downcall.trailer_size) != total) {
437                 gossip_err("%s: funky write, head_size:%d"
438                            ": downcall_size:%d: trailer_size:%lld"
439                            ": total size:%d:\n",
440                            __func__,
441                            head_size,
442                            downcall_size,
443                            op->downcall.trailer_size,
444                            total);
445                 goto Efault;
446         }
447
448         /* Only READDIR operations should have trailers. */
449         if ((op->downcall.type != ORANGEFS_VFS_OP_READDIR) &&
450             (op->downcall.trailer_size != 0)) {
451                 gossip_err("%s: %x operation with trailer.",
452                            __func__,
453                            op->downcall.type);
454                 goto Efault;
455         }
456
457         /* READDIR operations should always have trailers. */
458         if ((op->downcall.type == ORANGEFS_VFS_OP_READDIR) &&
459             (op->downcall.trailer_size == 0)) {
460                 gossip_err("%s: %x operation with no trailer.",
461                            __func__,
462                            op->downcall.type);
463                 goto Efault;
464         }
465
466         if (op->downcall.type != ORANGEFS_VFS_OP_READDIR)
467                 goto wakeup;
468
469         op->downcall.trailer_buf = vzalloc(op->downcall.trailer_size);
470         if (!op->downcall.trailer_buf)
471                 goto Enomem;
472
473         if (!copy_from_iter_full(op->downcall.trailer_buf,
474                                  op->downcall.trailer_size, iter)) {
475                 gossip_err("%s: failed to copy trailer.\n", __func__);
476                 vfree(op->downcall.trailer_buf);
477                 goto Efault;
478         }
479
480 wakeup:
481         /*
482          * Return to vfs waitqueue, and back to service_operation
483          * through wait_for_matching_downcall.
484          */
485         spin_lock(&op->lock);
486         if (unlikely(op_is_cancel(op))) {
487                 spin_unlock(&op->lock);
488                 put_cancel(op);
489         } else if (unlikely(op_state_given_up(op))) {
490                 spin_unlock(&op->lock);
491                 complete(&op->waitq);
492         } else {
493                 set_op_state_serviced(op);
494                 gossip_debug(GOSSIP_DEV_DEBUG,
495                              "%s: op:%s: op_state:%d: process:%s:\n",
496                              __func__,
497                              get_opname_string(op),
498                              op->op_state,
499                              current->comm);
500                 spin_unlock(&op->lock);
501         }
502         return ret;
503
504 Efault:
505         op->downcall.status = -(ORANGEFS_ERROR_BIT | 9);
506         ret = -EFAULT;
507         goto wakeup;
508
509 Enomem:
510         op->downcall.status = -(ORANGEFS_ERROR_BIT | 8);
511         ret = -ENOMEM;
512         goto wakeup;
513 }
514
515 /*
516  * NOTE: gets called when the last reference to this device is dropped.
517  * Using the open_access_count variable, we enforce a reference count
518  * on this file so that it can be opened by only one process at a time.
519  * the devreq_mutex is used to make sure all i/o has completed
520  * before we call orangefs_bufmap_finalize, and similar such tricky
521  * situations
522  */
523 static int orangefs_devreq_release(struct inode *inode, struct file *file)
524 {
525         int unmounted = 0;
526
527         gossip_debug(GOSSIP_DEV_DEBUG,
528                      "%s:pvfs2-client-core: exiting, closing device\n",
529                      __func__);
530
531         mutex_lock(&devreq_mutex);
532         orangefs_bufmap_finalize();
533
534         open_access_count = -1;
535
536         unmounted = mark_all_pending_mounts();
537         gossip_debug(GOSSIP_DEV_DEBUG, "ORANGEFS Device Close: Filesystem(s) %s\n",
538                      (unmounted ? "UNMOUNTED" : "MOUNTED"));
539
540         purge_waiting_ops();
541         purge_inprogress_ops();
542
543         orangefs_bufmap_run_down();
544
545         gossip_debug(GOSSIP_DEV_DEBUG,
546                      "pvfs2-client-core: device close complete\n");
547         open_access_count = 0;
548         orangefs_userspace_version = 0;
549         mutex_unlock(&devreq_mutex);
550         return 0;
551 }
552
553 int is_daemon_in_service(void)
554 {
555         int in_service;
556
557         /*
558          * What this function does is checks if client-core is alive
559          * based on the access count we maintain on the device.
560          */
561         mutex_lock(&devreq_mutex);
562         in_service = open_access_count == 1 ? 0 : -EIO;
563         mutex_unlock(&devreq_mutex);
564         return in_service;
565 }
566
567 bool __is_daemon_in_service(void)
568 {
569         return open_access_count == 1;
570 }
571
572 static inline long check_ioctl_command(unsigned int command)
573 {
574         /* Check for valid ioctl codes */
575         if (_IOC_TYPE(command) != ORANGEFS_DEV_MAGIC) {
576                 gossip_err("device ioctl magic numbers don't match! Did you rebuild pvfs2-client-core/libpvfs2? [cmd %x, magic %x != %x]\n",
577                         command,
578                         _IOC_TYPE(command),
579                         ORANGEFS_DEV_MAGIC);
580                 return -EINVAL;
581         }
582         /* and valid ioctl commands */
583         if (_IOC_NR(command) >= ORANGEFS_DEV_MAXNR || _IOC_NR(command) <= 0) {
584                 gossip_err("Invalid ioctl command number [%d >= %d]\n",
585                            _IOC_NR(command), ORANGEFS_DEV_MAXNR);
586                 return -ENOIOCTLCMD;
587         }
588         return 0;
589 }
590
591 static long dispatch_ioctl_command(unsigned int command, unsigned long arg)
592 {
593         static __s32 magic = ORANGEFS_DEVREQ_MAGIC;
594         static __s32 max_up_size = MAX_DEV_REQ_UPSIZE;
595         static __s32 max_down_size = MAX_DEV_REQ_DOWNSIZE;
596         struct ORANGEFS_dev_map_desc user_desc;
597         int ret = 0;
598         int upstream_kmod = 1;
599         struct orangefs_sb_info_s *orangefs_sb;
600
601         /* mtmoore: add locking here */
602
603         switch (command) {
604         case ORANGEFS_DEV_GET_MAGIC:
605                 return ((put_user(magic, (__s32 __user *) arg) == -EFAULT) ?
606                         -EIO :
607                         0);
608         case ORANGEFS_DEV_GET_MAX_UPSIZE:
609                 return ((put_user(max_up_size,
610                                   (__s32 __user *) arg) == -EFAULT) ?
611                                         -EIO :
612                                         0);
613         case ORANGEFS_DEV_GET_MAX_DOWNSIZE:
614                 return ((put_user(max_down_size,
615                                   (__s32 __user *) arg) == -EFAULT) ?
616                                         -EIO :
617                                         0);
618         case ORANGEFS_DEV_MAP:
619                 ret = copy_from_user(&user_desc,
620                                      (struct ORANGEFS_dev_map_desc __user *)
621                                      arg,
622                                      sizeof(struct ORANGEFS_dev_map_desc));
623                 /* WTF -EIO and not -EFAULT? */
624                 return ret ? -EIO : orangefs_bufmap_initialize(&user_desc);
625         case ORANGEFS_DEV_REMOUNT_ALL:
626                 gossip_debug(GOSSIP_DEV_DEBUG,
627                              "%s: got ORANGEFS_DEV_REMOUNT_ALL\n",
628                              __func__);
629
630                 /*
631                  * remount all mounted orangefs volumes to regain the lost
632                  * dynamic mount tables (if any) -- NOTE: this is done
633                  * without keeping the superblock list locked due to the
634                  * upcall/downcall waiting.  also, the request mutex is
635                  * used to ensure that no operations will be serviced until
636                  * all of the remounts are serviced (to avoid ops between
637                  * mounts to fail)
638                  */
639                 ret = mutex_lock_interruptible(&orangefs_request_mutex);
640                 if (ret < 0)
641                         return ret;
642                 gossip_debug(GOSSIP_DEV_DEBUG,
643                              "%s: priority remount in progress\n",
644                              __func__);
645                 spin_lock(&orangefs_superblocks_lock);
646                 list_for_each_entry(orangefs_sb, &orangefs_superblocks, list) {
647                         /*
648                          * We have to drop the spinlock, so entries can be
649                          * removed.  They can't be freed, though, so we just
650                          * keep the forward pointers and zero the back ones -
651                          * that way we can get to the rest of the list.
652                          */
653                         if (!orangefs_sb->list.prev)
654                                 continue;
655                         gossip_debug(GOSSIP_DEV_DEBUG,
656                                      "%s: Remounting SB %p\n",
657                                      __func__,
658                                      orangefs_sb);
659
660                         spin_unlock(&orangefs_superblocks_lock);
661                         ret = orangefs_remount(orangefs_sb);
662                         spin_lock(&orangefs_superblocks_lock);
663                         if (ret) {
664                                 gossip_debug(GOSSIP_DEV_DEBUG,
665                                              "SB %p remount failed\n",
666                                              orangefs_sb);
667                                 break;
668                         }
669                 }
670                 spin_unlock(&orangefs_superblocks_lock);
671                 gossip_debug(GOSSIP_DEV_DEBUG,
672                              "%s: priority remount complete\n",
673                              __func__);
674                 mutex_unlock(&orangefs_request_mutex);
675                 return ret;
676
677         case ORANGEFS_DEV_UPSTREAM:
678                 ret = copy_to_user((void __user *)arg,
679                                     &upstream_kmod,
680                                     sizeof(upstream_kmod));
681
682                 if (ret != 0)
683                         return -EIO;
684                 else
685                         return ret;
686
687         case ORANGEFS_DEV_CLIENT_MASK:
688                 return orangefs_debugfs_new_client_mask((void __user *)arg);
689         case ORANGEFS_DEV_CLIENT_STRING:
690                 return orangefs_debugfs_new_client_string((void __user *)arg);
691         case ORANGEFS_DEV_DEBUG:
692                 return orangefs_debugfs_new_debug((void __user *)arg);
693         default:
694                 return -ENOIOCTLCMD;
695         }
696         return -ENOIOCTLCMD;
697 }
698
699 static long orangefs_devreq_ioctl(struct file *file,
700                                unsigned int command, unsigned long arg)
701 {
702         long ret;
703
704         /* Check for properly constructed commands */
705         ret = check_ioctl_command(command);
706         if (ret < 0)
707                 return (int)ret;
708
709         return (int)dispatch_ioctl_command(command, arg);
710 }
711
712 #ifdef CONFIG_COMPAT            /* CONFIG_COMPAT is in .config */
713
714 /*  Compat structure for the ORANGEFS_DEV_MAP ioctl */
715 struct ORANGEFS_dev_map_desc32 {
716         compat_uptr_t ptr;
717         __s32 total_size;
718         __s32 size;
719         __s32 count;
720 };
721
722 /*
723  * 32 bit user-space apps' ioctl handlers when kernel modules
724  * is compiled as a 64 bit one
725  */
726 static long orangefs_devreq_compat_ioctl(struct file *filp, unsigned int cmd,
727                                       unsigned long args)
728 {
729         long ret;
730
731         /* Check for properly constructed commands */
732         ret = check_ioctl_command(cmd);
733         if (ret < 0)
734                 return ret;
735         if (cmd == ORANGEFS_DEV_MAP) {
736                 struct ORANGEFS_dev_map_desc desc;
737                 struct ORANGEFS_dev_map_desc32 d32;
738
739                 if (copy_from_user(&d32, (void __user *)args, sizeof(d32)))
740                         return -EFAULT;
741
742                 desc.ptr = compat_ptr(d32.ptr);
743                 desc.total_size = d32.total_size;
744                 desc.size = d32.size;
745                 desc.count = d32.count;
746                 return orangefs_bufmap_initialize(&desc);
747         }
748         /* no other ioctl requires translation */
749         return dispatch_ioctl_command(cmd, args);
750 }
751
752 #endif /* CONFIG_COMPAT is in .config */
753
754 static __poll_t orangefs_devreq_poll(struct file *file,
755                                       struct poll_table_struct *poll_table)
756 {
757         __poll_t poll_revent_mask = 0;
758
759         poll_wait(file, &orangefs_request_list_waitq, poll_table);
760
761         if (!list_empty(&orangefs_request_list))
762                 poll_revent_mask |= EPOLLIN;
763         return poll_revent_mask;
764 }
765
766 /* the assigned character device major number */
767 static int orangefs_dev_major;
768
769 static const struct file_operations orangefs_devreq_file_operations = {
770         .owner = THIS_MODULE,
771         .read = orangefs_devreq_read,
772         .write_iter = orangefs_devreq_write_iter,
773         .open = orangefs_devreq_open,
774         .release = orangefs_devreq_release,
775         .unlocked_ioctl = orangefs_devreq_ioctl,
776
777 #ifdef CONFIG_COMPAT            /* CONFIG_COMPAT is in .config */
778         .compat_ioctl = orangefs_devreq_compat_ioctl,
779 #endif
780         .poll = orangefs_devreq_poll
781 };
782
783 /*
784  * Initialize orangefs device specific state:
785  * Must be called at module load time only
786  */
787 int orangefs_dev_init(void)
788 {
789         /* register orangefs-req device  */
790         orangefs_dev_major = register_chrdev(0,
791                                           ORANGEFS_REQDEVICE_NAME,
792                                           &orangefs_devreq_file_operations);
793         if (orangefs_dev_major < 0) {
794                 gossip_debug(GOSSIP_DEV_DEBUG,
795                              "Failed to register /dev/%s (error %d)\n",
796                              ORANGEFS_REQDEVICE_NAME, orangefs_dev_major);
797                 return orangefs_dev_major;
798         }
799
800         gossip_debug(GOSSIP_DEV_DEBUG,
801                      "*** /dev/%s character device registered ***\n",
802                      ORANGEFS_REQDEVICE_NAME);
803         gossip_debug(GOSSIP_DEV_DEBUG, "'mknod /dev/%s c %d 0'.\n",
804                      ORANGEFS_REQDEVICE_NAME, orangefs_dev_major);
805         return 0;
806 }
807
808 void orangefs_dev_cleanup(void)
809 {
810         unregister_chrdev(orangefs_dev_major, ORANGEFS_REQDEVICE_NAME);
811         gossip_debug(GOSSIP_DEV_DEBUG,
812                      "*** /dev/%s character device unregistered ***\n",
813                      ORANGEFS_REQDEVICE_NAME);
814 }