Linux-libre 5.3.12-gnu
[librecmc/linux-libre.git] / fs / orangefs / file.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * (C) 2001 Clemson University and The University of Chicago
4  * Copyright 2018 Omnibond Systems, L.L.C.
5  *
6  * See COPYING in top-level directory.
7  */
8
9 /*
10  *  Linux VFS file operations.
11  */
12
13 #include "protocol.h"
14 #include "orangefs-kernel.h"
15 #include "orangefs-bufmap.h"
16 #include <linux/fs.h>
17 #include <linux/pagemap.h>
18
19 static int flush_racache(struct inode *inode)
20 {
21         struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
22         struct orangefs_kernel_op_s *new_op;
23         int ret;
24
25         gossip_debug(GOSSIP_UTILS_DEBUG,
26             "%s: %pU: Handle is %pU | fs_id %d\n", __func__,
27             get_khandle_from_ino(inode), &orangefs_inode->refn.khandle,
28             orangefs_inode->refn.fs_id);
29
30         new_op = op_alloc(ORANGEFS_VFS_OP_RA_FLUSH);
31         if (!new_op)
32                 return -ENOMEM;
33         new_op->upcall.req.ra_cache_flush.refn = orangefs_inode->refn;
34
35         ret = service_operation(new_op, "orangefs_flush_racache",
36             get_interruptible_flag(inode));
37
38         gossip_debug(GOSSIP_UTILS_DEBUG, "%s: got return value of %d\n",
39             __func__, ret);
40
41         op_release(new_op);
42         return ret;
43 }
44
45 /*
46  * Post and wait for the I/O upcall to finish
47  */
48 ssize_t wait_for_direct_io(enum ORANGEFS_io_type type, struct inode *inode,
49     loff_t *offset, struct iov_iter *iter, size_t total_size,
50     loff_t readahead_size, struct orangefs_write_range *wr, int *index_return)
51 {
52         struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
53         struct orangefs_khandle *handle = &orangefs_inode->refn.khandle;
54         struct orangefs_kernel_op_s *new_op = NULL;
55         int buffer_index;
56         ssize_t ret;
57         size_t copy_amount;
58
59         new_op = op_alloc(ORANGEFS_VFS_OP_FILE_IO);
60         if (!new_op)
61                 return -ENOMEM;
62
63         /* synchronous I/O */
64         new_op->upcall.req.io.readahead_size = readahead_size;
65         new_op->upcall.req.io.io_type = type;
66         new_op->upcall.req.io.refn = orangefs_inode->refn;
67
68 populate_shared_memory:
69         /* get a shared buffer index */
70         buffer_index = orangefs_bufmap_get();
71         if (buffer_index < 0) {
72                 ret = buffer_index;
73                 gossip_debug(GOSSIP_FILE_DEBUG,
74                              "%s: orangefs_bufmap_get failure (%zd)\n",
75                              __func__, ret);
76                 goto out;
77         }
78         gossip_debug(GOSSIP_FILE_DEBUG,
79                      "%s(%pU): GET op %p -> buffer_index %d\n",
80                      __func__,
81                      handle,
82                      new_op,
83                      buffer_index);
84
85         new_op->uses_shared_memory = 1;
86         new_op->upcall.req.io.buf_index = buffer_index;
87         new_op->upcall.req.io.count = total_size;
88         new_op->upcall.req.io.offset = *offset;
89         if (type == ORANGEFS_IO_WRITE && wr) {
90                 new_op->upcall.uid = from_kuid(&init_user_ns, wr->uid);
91                 new_op->upcall.gid = from_kgid(&init_user_ns, wr->gid);
92         }
93
94         gossip_debug(GOSSIP_FILE_DEBUG,
95                      "%s(%pU): offset: %llu total_size: %zd\n",
96                      __func__,
97                      handle,
98                      llu(*offset),
99                      total_size);
100         /*
101          * Stage 1: copy the buffers into client-core's address space
102          */
103         if (type == ORANGEFS_IO_WRITE && total_size) {
104                 ret = orangefs_bufmap_copy_from_iovec(iter, buffer_index,
105                     total_size);
106                 if (ret < 0) {
107                         gossip_err("%s: Failed to copy-in buffers. Please make sure that the pvfs2-client is running. %ld\n",
108                             __func__, (long)ret);
109                         goto out;
110                 }
111         }
112
113         gossip_debug(GOSSIP_FILE_DEBUG,
114                      "%s(%pU): Calling post_io_request with tag (%llu)\n",
115                      __func__,
116                      handle,
117                      llu(new_op->tag));
118
119         /* Stage 2: Service the I/O operation */
120         ret = service_operation(new_op,
121                                 type == ORANGEFS_IO_WRITE ?
122                                         "file_write" :
123                                         "file_read",
124                                 get_interruptible_flag(inode));
125
126         /*
127          * If service_operation() returns -EAGAIN #and# the operation was
128          * purged from orangefs_request_list or htable_ops_in_progress, then
129          * we know that the client was restarted, causing the shared memory
130          * area to be wiped clean.  To restart a  write operation in this
131          * case, we must re-copy the data from the user's iovec to a NEW
132          * shared memory location. To restart a read operation, we must get
133          * a new shared memory location.
134          */
135         if (ret == -EAGAIN && op_state_purged(new_op)) {
136                 orangefs_bufmap_put(buffer_index);
137                 if (type == ORANGEFS_IO_WRITE)
138                         iov_iter_revert(iter, total_size);
139                 gossip_debug(GOSSIP_FILE_DEBUG,
140                              "%s:going to repopulate_shared_memory.\n",
141                              __func__);
142                 goto populate_shared_memory;
143         }
144
145         if (ret < 0) {
146                 if (ret == -EINTR) {
147                         /*
148                          * We can't return EINTR if any data was written,
149                          * it's not POSIX. It is minimally acceptable
150                          * to give a partial write, the way NFS does.
151                          *
152                          * It would be optimal to return all or nothing,
153                          * but if a userspace write is bigger than
154                          * an IO buffer, and the interrupt occurs
155                          * between buffer writes, that would not be
156                          * possible.
157                          */
158                         switch (new_op->op_state - OP_VFS_STATE_GIVEN_UP) {
159                         /*
160                          * If the op was waiting when the interrupt
161                          * occurred, then the client-core did not
162                          * trigger the write.
163                          */
164                         case OP_VFS_STATE_WAITING:
165                                 if (*offset == 0)
166                                         ret = -EINTR;
167                                 else
168                                         ret = 0;
169                                 break;
170                         /*
171                          * If the op was in progress when the interrupt
172                          * occurred, then the client-core was able to
173                          * trigger the write.
174                          */
175                         case OP_VFS_STATE_INPROGR:
176                                 if (type == ORANGEFS_IO_READ)
177                                         ret = -EINTR;
178                                 else
179                                         ret = total_size;
180                                 break;
181                         default:
182                                 gossip_err("%s: unexpected op state :%d:.\n",
183                                            __func__,
184                                            new_op->op_state);
185                                 ret = 0;
186                                 break;
187                         }
188                         gossip_debug(GOSSIP_FILE_DEBUG,
189                                      "%s: got EINTR, state:%d: %p\n",
190                                      __func__,
191                                      new_op->op_state,
192                                      new_op);
193                 } else {
194                         gossip_err("%s: error in %s handle %pU, returning %zd\n",
195                                 __func__,
196                                 type == ORANGEFS_IO_READ ?
197                                         "read from" : "write to",
198                                 handle, ret);
199                 }
200                 if (orangefs_cancel_op_in_progress(new_op))
201                         return ret;
202
203                 goto out;
204         }
205
206         /*
207          * Stage 3: Post copy buffers from client-core's address space
208          */
209         if (type == ORANGEFS_IO_READ && new_op->downcall.resp.io.amt_complete) {
210                 /*
211                  * NOTE: the iovector can either contain addresses which
212                  *       can futher be kernel-space or user-space addresses.
213                  *       or it can pointers to struct page's
214                  */
215
216                 /*
217                  * When reading, readahead_size will only be zero when
218                  * we're doing O_DIRECT, otherwise we got here from
219                  * orangefs_readpage.
220                  *
221                  * If we got here from orangefs_readpage we want to
222                  * copy either a page or the whole file into the io
223                  * vector, whichever is smaller.
224                  */
225                 if (readahead_size)
226                         copy_amount =
227                                 min(new_op->downcall.resp.io.amt_complete,
228                                         (__s64)PAGE_SIZE);
229                 else
230                         copy_amount = new_op->downcall.resp.io.amt_complete;
231
232                 ret = orangefs_bufmap_copy_to_iovec(iter, buffer_index,
233                         copy_amount);
234                 if (ret < 0) {
235                         gossip_err("%s: Failed to copy-out buffers. Please make sure that the pvfs2-client is running (%ld)\n",
236                             __func__, (long)ret);
237                         goto out;
238                 }
239         }
240         gossip_debug(GOSSIP_FILE_DEBUG,
241             "%s(%pU): Amount %s, returned by the sys-io call:%d\n",
242             __func__,
243             handle,
244             type == ORANGEFS_IO_READ ?  "read" : "written",
245             (int)new_op->downcall.resp.io.amt_complete);
246
247         ret = new_op->downcall.resp.io.amt_complete;
248
249 out:
250         if (buffer_index >= 0) {
251                 if ((readahead_size) && (type == ORANGEFS_IO_READ)) {
252                         /* readpage */
253                         *index_return = buffer_index;
254                         gossip_debug(GOSSIP_FILE_DEBUG,
255                                 "%s: hold on to buffer_index :%d:\n",
256                                 __func__, buffer_index);
257                 } else {
258                         /* O_DIRECT */
259                         orangefs_bufmap_put(buffer_index);
260                         gossip_debug(GOSSIP_FILE_DEBUG,
261                                 "%s(%pU): PUT buffer_index %d\n",
262                                 __func__, handle, buffer_index);
263                 }
264         }
265         op_release(new_op);
266         return ret;
267 }
268
269 int orangefs_revalidate_mapping(struct inode *inode)
270 {
271         struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
272         struct address_space *mapping = inode->i_mapping;
273         unsigned long *bitlock = &orangefs_inode->bitlock;
274         int ret;
275
276         while (1) {
277                 ret = wait_on_bit(bitlock, 1, TASK_KILLABLE);
278                 if (ret)
279                         return ret;
280                 spin_lock(&inode->i_lock);
281                 if (test_bit(1, bitlock)) {
282                         spin_unlock(&inode->i_lock);
283                         continue;
284                 }
285                 if (!time_before(jiffies, orangefs_inode->mapping_time))
286                         break;
287                 spin_unlock(&inode->i_lock);
288                 return 0;
289         }
290
291         set_bit(1, bitlock);
292         smp_wmb();
293         spin_unlock(&inode->i_lock);
294
295         unmap_mapping_range(mapping, 0, 0, 0);
296         ret = filemap_write_and_wait(mapping);
297         if (!ret)
298                 ret = invalidate_inode_pages2(mapping);
299
300         orangefs_inode->mapping_time = jiffies +
301             orangefs_cache_timeout_msecs*HZ/1000;
302
303         clear_bit(1, bitlock);
304         smp_mb__after_atomic();
305         wake_up_bit(bitlock, 1);
306
307         return ret;
308 }
309
310 static ssize_t orangefs_file_read_iter(struct kiocb *iocb,
311     struct iov_iter *iter)
312 {
313         int ret;
314         struct orangefs_read_options *ro;
315
316         orangefs_stats.reads++;
317
318         /*
319          * Remember how they set "count" in read(2) or pread(2) or whatever -
320          * users can use count as a knob to control orangefs io size and later
321          * we can try to help them fill as many pages as possible in readpage.
322          */
323         if (!iocb->ki_filp->private_data) {
324                 iocb->ki_filp->private_data = kmalloc(sizeof *ro, GFP_KERNEL);
325                 if (!iocb->ki_filp->private_data)
326                         return(ENOMEM);
327                 ro = iocb->ki_filp->private_data;
328                 ro->blksiz = iter->count;
329         }
330
331         down_read(&file_inode(iocb->ki_filp)->i_rwsem);
332         ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp));
333         if (ret)
334                 goto out;
335
336         ret = generic_file_read_iter(iocb, iter);
337 out:
338         up_read(&file_inode(iocb->ki_filp)->i_rwsem);
339         return ret;
340 }
341
342 static ssize_t orangefs_file_write_iter(struct kiocb *iocb,
343     struct iov_iter *iter)
344 {
345         int ret;
346         orangefs_stats.writes++;
347
348         if (iocb->ki_pos > i_size_read(file_inode(iocb->ki_filp))) {
349                 ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp));
350                 if (ret)
351                         return ret;
352         }
353
354         ret = generic_file_write_iter(iocb, iter);
355         return ret;
356 }
357
358 static int orangefs_getflags(struct inode *inode, unsigned long *uval)
359 {
360         __u64 val = 0;
361         int ret;
362
363         ret = orangefs_inode_getxattr(inode,
364                                       "user.pvfs2.meta_hint",
365                                       &val, sizeof(val));
366         if (ret < 0 && ret != -ENODATA)
367                 return ret;
368         else if (ret == -ENODATA)
369                 val = 0;
370         *uval = val;
371         return 0;
372 }
373
374 /*
375  * Perform a miscellaneous operation on a file.
376  */
377 static long orangefs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
378 {
379         struct inode *inode = file_inode(file);
380         int ret = -ENOTTY;
381         __u64 val = 0;
382         unsigned long uval;
383
384         gossip_debug(GOSSIP_FILE_DEBUG,
385                      "orangefs_ioctl: called with cmd %d\n",
386                      cmd);
387
388         /*
389          * we understand some general ioctls on files, such as the immutable
390          * and append flags
391          */
392         if (cmd == FS_IOC_GETFLAGS) {
393                 ret = orangefs_getflags(inode, &uval);
394                 if (ret)
395                         return ret;
396                 gossip_debug(GOSSIP_FILE_DEBUG,
397                              "orangefs_ioctl: FS_IOC_GETFLAGS: %llu\n",
398                              (unsigned long long)uval);
399                 return put_user(uval, (int __user *)arg);
400         } else if (cmd == FS_IOC_SETFLAGS) {
401                 unsigned long old_uval;
402
403                 ret = 0;
404                 if (get_user(uval, (int __user *)arg))
405                         return -EFAULT;
406                 /*
407                  * ORANGEFS_MIRROR_FL is set internally when the mirroring mode
408                  * is turned on for a file. The user is not allowed to turn
409                  * on this bit, but the bit is present if the user first gets
410                  * the flags and then updates the flags with some new
411                  * settings. So, we ignore it in the following edit. bligon.
412                  */
413                 if ((uval & ~ORANGEFS_MIRROR_FL) &
414                     (~(FS_IMMUTABLE_FL | FS_APPEND_FL | FS_NOATIME_FL))) {
415                         gossip_err("orangefs_ioctl: the FS_IOC_SETFLAGS only supports setting one of FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NOATIME_FL\n");
416                         return -EINVAL;
417                 }
418                 ret = orangefs_getflags(inode, &old_uval);
419                 if (ret)
420                         return ret;
421                 ret = vfs_ioc_setflags_prepare(inode, old_uval, uval);
422                 if (ret)
423                         return ret;
424                 val = uval;
425                 gossip_debug(GOSSIP_FILE_DEBUG,
426                              "orangefs_ioctl: FS_IOC_SETFLAGS: %llu\n",
427                              (unsigned long long)val);
428                 ret = orangefs_inode_setxattr(inode,
429                                               "user.pvfs2.meta_hint",
430                                               &val, sizeof(val), 0);
431         }
432
433         return ret;
434 }
435
436 static vm_fault_t orangefs_fault(struct vm_fault *vmf)
437 {
438         struct file *file = vmf->vma->vm_file;
439         int ret;
440         ret = orangefs_inode_getattr(file->f_mapping->host,
441             ORANGEFS_GETATTR_SIZE);
442         if (ret == -ESTALE)
443                 ret = -EIO;
444         if (ret) {
445                 gossip_err("%s: orangefs_inode_getattr failed, "
446                     "ret:%d:.\n", __func__, ret);
447                 return VM_FAULT_SIGBUS;
448         }
449         return filemap_fault(vmf);
450 }
451
452 static const struct vm_operations_struct orangefs_file_vm_ops = {
453         .fault = orangefs_fault,
454         .map_pages = filemap_map_pages,
455         .page_mkwrite = orangefs_page_mkwrite,
456 };
457
458 /*
459  * Memory map a region of a file.
460  */
461 static int orangefs_file_mmap(struct file *file, struct vm_area_struct *vma)
462 {
463         int ret;
464
465         ret = orangefs_revalidate_mapping(file_inode(file));
466         if (ret)
467                 return ret;
468
469         gossip_debug(GOSSIP_FILE_DEBUG,
470                      "orangefs_file_mmap: called on %s\n",
471                      (file ?
472                         (char *)file->f_path.dentry->d_name.name :
473                         (char *)"Unknown"));
474
475         /* set the sequential readahead hint */
476         vma->vm_flags |= VM_SEQ_READ;
477         vma->vm_flags &= ~VM_RAND_READ;
478
479         file_accessed(file);
480         vma->vm_ops = &orangefs_file_vm_ops;
481         return 0;
482 }
483
484 #define mapping_nrpages(idata) ((idata)->nrpages)
485
486 /*
487  * Called to notify the module that there are no more references to
488  * this file (i.e. no processes have it open).
489  *
490  * \note Not called when each file is closed.
491  */
492 static int orangefs_file_release(struct inode *inode, struct file *file)
493 {
494         gossip_debug(GOSSIP_FILE_DEBUG,
495                      "orangefs_file_release: called on %pD\n",
496                      file);
497
498         /*
499          * remove all associated inode pages from the page cache and
500          * readahead cache (if any); this forces an expensive refresh of
501          * data for the next caller of mmap (or 'get_block' accesses)
502          */
503         if (file_inode(file) &&
504             file_inode(file)->i_mapping &&
505             mapping_nrpages(&file_inode(file)->i_data)) {
506                 if (orangefs_features & ORANGEFS_FEATURE_READAHEAD) {
507                         gossip_debug(GOSSIP_INODE_DEBUG,
508                             "calling flush_racache on %pU\n",
509                             get_khandle_from_ino(inode));
510                         flush_racache(inode);
511                         gossip_debug(GOSSIP_INODE_DEBUG,
512                             "flush_racache finished\n");
513                 }
514
515         }
516         return 0;
517 }
518
519 /*
520  * Push all data for a specific file onto permanent storage.
521  */
522 static int orangefs_fsync(struct file *file,
523                        loff_t start,
524                        loff_t end,
525                        int datasync)
526 {
527         int ret;
528         struct orangefs_inode_s *orangefs_inode =
529                 ORANGEFS_I(file_inode(file));
530         struct orangefs_kernel_op_s *new_op = NULL;
531
532         ret = filemap_write_and_wait_range(file_inode(file)->i_mapping,
533             start, end);
534         if (ret < 0)
535                 return ret;
536
537         new_op = op_alloc(ORANGEFS_VFS_OP_FSYNC);
538         if (!new_op)
539                 return -ENOMEM;
540         new_op->upcall.req.fsync.refn = orangefs_inode->refn;
541
542         ret = service_operation(new_op,
543                         "orangefs_fsync",
544                         get_interruptible_flag(file_inode(file)));
545
546         gossip_debug(GOSSIP_FILE_DEBUG,
547                      "orangefs_fsync got return value of %d\n",
548                      ret);
549
550         op_release(new_op);
551         return ret;
552 }
553
554 /*
555  * Change the file pointer position for an instance of an open file.
556  *
557  * \note If .llseek is overriden, we must acquire lock as described in
558  *       Documentation/filesystems/Locking.
559  *
560  * Future upgrade could support SEEK_DATA and SEEK_HOLE but would
561  * require much changes to the FS
562  */
563 static loff_t orangefs_file_llseek(struct file *file, loff_t offset, int origin)
564 {
565         int ret = -EINVAL;
566         struct inode *inode = file_inode(file);
567
568         if (origin == SEEK_END) {
569                 /*
570                  * revalidate the inode's file size.
571                  * NOTE: We are only interested in file size here,
572                  * so we set mask accordingly.
573                  */
574                 ret = orangefs_inode_getattr(file->f_mapping->host,
575                     ORANGEFS_GETATTR_SIZE);
576                 if (ret == -ESTALE)
577                         ret = -EIO;
578                 if (ret) {
579                         gossip_debug(GOSSIP_FILE_DEBUG,
580                                      "%s:%s:%d calling make bad inode\n",
581                                      __FILE__,
582                                      __func__,
583                                      __LINE__);
584                         return ret;
585                 }
586         }
587
588         gossip_debug(GOSSIP_FILE_DEBUG,
589                      "orangefs_file_llseek: offset is %ld | origin is %d"
590                      " | inode size is %lu\n",
591                      (long)offset,
592                      origin,
593                      (unsigned long)i_size_read(inode));
594
595         return generic_file_llseek(file, offset, origin);
596 }
597
598 /*
599  * Support local locks (locks that only this kernel knows about)
600  * if Orangefs was mounted -o local_lock.
601  */
602 static int orangefs_lock(struct file *filp, int cmd, struct file_lock *fl)
603 {
604         int rc = -EINVAL;
605
606         if (ORANGEFS_SB(file_inode(filp)->i_sb)->flags & ORANGEFS_OPT_LOCAL_LOCK) {
607                 if (cmd == F_GETLK) {
608                         rc = 0;
609                         posix_test_lock(filp, fl);
610                 } else {
611                         rc = posix_lock_file(filp, fl, NULL);
612                 }
613         }
614
615         return rc;
616 }
617
618 static int orangefs_file_open(struct inode * inode, struct file *file)
619 {
620         file->private_data = NULL;
621         return generic_file_open(inode, file);
622 }
623
624 static int orangefs_flush(struct file *file, fl_owner_t id)
625 {
626         /*
627          * This is vfs_fsync_range(file, 0, LLONG_MAX, 0) without the
628          * service_operation in orangefs_fsync.
629          *
630          * Do not send fsync to OrangeFS server on a close.  Do send fsync
631          * on an explicit fsync call.  This duplicates historical OrangeFS
632          * behavior.
633          */
634         struct inode *inode = file->f_mapping->host;
635         int r;
636
637         kfree(file->private_data);
638         file->private_data = NULL;
639
640         if (inode->i_state & I_DIRTY_TIME) {
641                 spin_lock(&inode->i_lock);
642                 inode->i_state &= ~I_DIRTY_TIME;
643                 spin_unlock(&inode->i_lock);
644                 mark_inode_dirty_sync(inode);
645         }
646
647         r = filemap_write_and_wait_range(file->f_mapping, 0, LLONG_MAX);
648         if (r > 0)
649                 return 0;
650         else
651                 return r;
652 }
653
654 /** ORANGEFS implementation of VFS file operations */
655 const struct file_operations orangefs_file_operations = {
656         .llseek         = orangefs_file_llseek,
657         .read_iter      = orangefs_file_read_iter,
658         .write_iter     = orangefs_file_write_iter,
659         .lock           = orangefs_lock,
660         .unlocked_ioctl = orangefs_ioctl,
661         .mmap           = orangefs_file_mmap,
662         .open           = orangefs_file_open,
663         .flush          = orangefs_flush,
664         .release        = orangefs_file_release,
665         .fsync          = orangefs_fsync,
666 };