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v6.9.4
  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/filelock.h>
 18#include <linux/pagemap.h>
 19
 20static int flush_racache(struct inode *inode)
 21{
 22	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
 23	struct orangefs_kernel_op_s *new_op;
 24	int ret;
 25
 26	gossip_debug(GOSSIP_UTILS_DEBUG,
 27	    "%s: %pU: Handle is %pU | fs_id %d\n", __func__,
 28	    get_khandle_from_ino(inode), &orangefs_inode->refn.khandle,
 29	    orangefs_inode->refn.fs_id);
 30
 31	new_op = op_alloc(ORANGEFS_VFS_OP_RA_FLUSH);
 32	if (!new_op)
 33		return -ENOMEM;
 34	new_op->upcall.req.ra_cache_flush.refn = orangefs_inode->refn;
 35
 36	ret = service_operation(new_op, "orangefs_flush_racache",
 37	    get_interruptible_flag(inode));
 38
 39	gossip_debug(GOSSIP_UTILS_DEBUG, "%s: got return value of %d\n",
 40	    __func__, ret);
 41
 42	op_release(new_op);
 43	return ret;
 44}
 45
 46/*
 47 * Post and wait for the I/O upcall to finish
 48 */
 49ssize_t wait_for_direct_io(enum ORANGEFS_io_type type, struct inode *inode,
 50	loff_t *offset, struct iov_iter *iter, size_t total_size,
 51	loff_t readahead_size, struct orangefs_write_range *wr,
 52	int *index_return, struct file *file)
 53{
 54	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
 55	struct orangefs_khandle *handle = &orangefs_inode->refn.khandle;
 56	struct orangefs_kernel_op_s *new_op = NULL;
 57	int buffer_index;
 58	ssize_t ret;
 59	size_t copy_amount;
 60	int open_for_read;
 61	int open_for_write;
 62
 63	new_op = op_alloc(ORANGEFS_VFS_OP_FILE_IO);
 64	if (!new_op)
 65		return -ENOMEM;
 66
 67	/* synchronous I/O */
 68	new_op->upcall.req.io.readahead_size = readahead_size;
 69	new_op->upcall.req.io.io_type = type;
 70	new_op->upcall.req.io.refn = orangefs_inode->refn;
 71
 72populate_shared_memory:
 73	/* get a shared buffer index */
 74	buffer_index = orangefs_bufmap_get();
 75	if (buffer_index < 0) {
 76		ret = buffer_index;
 77		gossip_debug(GOSSIP_FILE_DEBUG,
 78			     "%s: orangefs_bufmap_get failure (%zd)\n",
 79			     __func__, ret);
 80		goto out;
 81	}
 82	gossip_debug(GOSSIP_FILE_DEBUG,
 83		     "%s(%pU): GET op %p -> buffer_index %d\n",
 84		     __func__,
 85		     handle,
 86		     new_op,
 87		     buffer_index);
 88
 89	new_op->uses_shared_memory = 1;
 90	new_op->upcall.req.io.buf_index = buffer_index;
 91	new_op->upcall.req.io.count = total_size;
 92	new_op->upcall.req.io.offset = *offset;
 93	if (type == ORANGEFS_IO_WRITE && wr) {
 94		new_op->upcall.uid = from_kuid(&init_user_ns, wr->uid);
 95		new_op->upcall.gid = from_kgid(&init_user_ns, wr->gid);
 96	}
 97	/*
 98	 * Orangefs has no open, and orangefs checks file permissions
 99	 * on each file access. Posix requires that file permissions
100	 * be checked on open and nowhere else. Orangefs-through-the-kernel
101	 * needs to seem posix compliant.
102	 *
103	 * The VFS opens files, even if the filesystem provides no
104	 * method. We can see if a file was successfully opened for
105	 * read and or for write by looking at file->f_mode.
106	 *
107	 * When writes are flowing from the page cache, file is no
108	 * longer available. We can trust the VFS to have checked
109	 * file->f_mode before writing to the page cache.
110	 *
111	 * The mode of a file might change between when it is opened
112	 * and IO commences, or it might be created with an arbitrary mode.
113	 *
114	 * We'll make sure we don't hit EACCES during the IO stage by
115	 * using UID 0. Some of the time we have access without changing
116	 * to UID 0 - how to check?
117	 */
118	if (file) {
119		open_for_write = file->f_mode & FMODE_WRITE;
120		open_for_read = file->f_mode & FMODE_READ;
121	} else {
122		open_for_write = 1;
123		open_for_read = 0; /* not relevant? */
124	}
125	if ((type == ORANGEFS_IO_WRITE) && open_for_write)
126		new_op->upcall.uid = 0;
127	if ((type == ORANGEFS_IO_READ) && open_for_read)
128		new_op->upcall.uid = 0;
129
130	gossip_debug(GOSSIP_FILE_DEBUG,
131		     "%s(%pU): offset: %llu total_size: %zd\n",
132		     __func__,
133		     handle,
134		     llu(*offset),
135		     total_size);
136	/*
137	 * Stage 1: copy the buffers into client-core's address space
138	 */
139	if (type == ORANGEFS_IO_WRITE && total_size) {
140		ret = orangefs_bufmap_copy_from_iovec(iter, buffer_index,
141		    total_size);
142		if (ret < 0) {
143			gossip_err("%s: Failed to copy-in buffers. Please make sure that the pvfs2-client is running. %ld\n",
144			    __func__, (long)ret);
145			goto out;
146		}
147	}
148
149	gossip_debug(GOSSIP_FILE_DEBUG,
150		     "%s(%pU): Calling post_io_request with tag (%llu)\n",
151		     __func__,
152		     handle,
153		     llu(new_op->tag));
154
155	/* Stage 2: Service the I/O operation */
156	ret = service_operation(new_op,
157				type == ORANGEFS_IO_WRITE ?
158					"file_write" :
159					"file_read",
160				get_interruptible_flag(inode));
161
162	/*
163	 * If service_operation() returns -EAGAIN #and# the operation was
164	 * purged from orangefs_request_list or htable_ops_in_progress, then
165	 * we know that the client was restarted, causing the shared memory
166	 * area to be wiped clean.  To restart a  write operation in this
167	 * case, we must re-copy the data from the user's iovec to a NEW
168	 * shared memory location. To restart a read operation, we must get
169	 * a new shared memory location.
170	 */
171	if (ret == -EAGAIN && op_state_purged(new_op)) {
172		orangefs_bufmap_put(buffer_index);
173		if (type == ORANGEFS_IO_WRITE)
174			iov_iter_revert(iter, total_size);
175		gossip_debug(GOSSIP_FILE_DEBUG,
176			     "%s:going to repopulate_shared_memory.\n",
177			     __func__);
178		goto populate_shared_memory;
179	}
180
181	if (ret < 0) {
182		if (ret == -EINTR) {
183			/*
184			 * We can't return EINTR if any data was written,
185			 * it's not POSIX. It is minimally acceptable
186			 * to give a partial write, the way NFS does.
187			 *
188			 * It would be optimal to return all or nothing,
189			 * but if a userspace write is bigger than
190			 * an IO buffer, and the interrupt occurs
191			 * between buffer writes, that would not be
192			 * possible.
193			 */
194			switch (new_op->op_state - OP_VFS_STATE_GIVEN_UP) {
195			/*
196			 * If the op was waiting when the interrupt
197			 * occurred, then the client-core did not
198			 * trigger the write.
199			 */
200			case OP_VFS_STATE_WAITING:
201				if (*offset == 0)
202					ret = -EINTR;
203				else
204					ret = 0;
205				break;
206			/*
207			 * If the op was in progress when the interrupt
208			 * occurred, then the client-core was able to
209			 * trigger the write.
210			 */
211			case OP_VFS_STATE_INPROGR:
212				if (type == ORANGEFS_IO_READ)
213					ret = -EINTR;
214				else
215					ret = total_size;
216				break;
217			default:
218				gossip_err("%s: unexpected op state :%d:.\n",
219					   __func__,
220					   new_op->op_state);
221				ret = 0;
222				break;
223			}
224			gossip_debug(GOSSIP_FILE_DEBUG,
225				     "%s: got EINTR, state:%d: %p\n",
226				     __func__,
227				     new_op->op_state,
228				     new_op);
229		} else {
230			gossip_err("%s: error in %s handle %pU, returning %zd\n",
231				__func__,
232				type == ORANGEFS_IO_READ ?
233					"read from" : "write to",
234				handle, ret);
235		}
236		if (orangefs_cancel_op_in_progress(new_op))
237			return ret;
238
239		goto out;
240	}
241
242	/*
243	 * Stage 3: Post copy buffers from client-core's address space
244	 */
245	if (type == ORANGEFS_IO_READ && new_op->downcall.resp.io.amt_complete) {
246		/*
247		 * NOTE: the iovector can either contain addresses which
248		 *       can futher be kernel-space or user-space addresses.
249		 *       or it can pointers to struct page's
250		 */
251
252		copy_amount = new_op->downcall.resp.io.amt_complete;
253
254		ret = orangefs_bufmap_copy_to_iovec(iter, buffer_index,
255			copy_amount);
256		if (ret < 0) {
257			gossip_err("%s: Failed to copy-out buffers. Please make sure that the pvfs2-client is running (%ld)\n",
258			    __func__, (long)ret);
259			goto out;
260		}
261	}
262	gossip_debug(GOSSIP_FILE_DEBUG,
263	    "%s(%pU): Amount %s, returned by the sys-io call:%d\n",
264	    __func__,
265	    handle,
266	    type == ORANGEFS_IO_READ ?  "read" : "written",
267	    (int)new_op->downcall.resp.io.amt_complete);
268
269	ret = new_op->downcall.resp.io.amt_complete;
270
271out:
272	if (buffer_index >= 0) {
273		orangefs_bufmap_put(buffer_index);
274		gossip_debug(GOSSIP_FILE_DEBUG,
275			"%s(%pU): PUT buffer_index %d\n",
276			__func__, handle, buffer_index);
 
277	}
278	op_release(new_op);
279	return ret;
280}
281
282int orangefs_revalidate_mapping(struct inode *inode)
283{
284	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
285	struct address_space *mapping = inode->i_mapping;
286	unsigned long *bitlock = &orangefs_inode->bitlock;
287	int ret;
288
289	while (1) {
290		ret = wait_on_bit(bitlock, 1, TASK_KILLABLE);
291		if (ret)
292			return ret;
293		spin_lock(&inode->i_lock);
294		if (test_bit(1, bitlock)) {
295			spin_unlock(&inode->i_lock);
296			continue;
297		}
298		if (!time_before(jiffies, orangefs_inode->mapping_time))
299			break;
300		spin_unlock(&inode->i_lock);
301		return 0;
302	}
303
304	set_bit(1, bitlock);
305	smp_wmb();
306	spin_unlock(&inode->i_lock);
307
308	unmap_mapping_range(mapping, 0, 0, 0);
309	ret = filemap_write_and_wait(mapping);
310	if (!ret)
311		ret = invalidate_inode_pages2(mapping);
312
313	orangefs_inode->mapping_time = jiffies +
314	    orangefs_cache_timeout_msecs*HZ/1000;
315
316	clear_bit(1, bitlock);
317	smp_mb__after_atomic();
318	wake_up_bit(bitlock, 1);
319
320	return ret;
321}
322
323static ssize_t orangefs_file_read_iter(struct kiocb *iocb,
324    struct iov_iter *iter)
325{
326	int ret;
327	orangefs_stats.reads++;
328
329	down_read(&file_inode(iocb->ki_filp)->i_rwsem);
330	ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp));
331	if (ret)
332		goto out;
333
334	ret = generic_file_read_iter(iocb, iter);
335out:
336	up_read(&file_inode(iocb->ki_filp)->i_rwsem);
337	return ret;
338}
339
340static ssize_t orangefs_file_splice_read(struct file *in, loff_t *ppos,
341					 struct pipe_inode_info *pipe,
342					 size_t len, unsigned int flags)
343{
344	struct inode *inode = file_inode(in);
345	ssize_t ret;
346
347	orangefs_stats.reads++;
348
349	down_read(&inode->i_rwsem);
350	ret = orangefs_revalidate_mapping(inode);
351	if (ret)
352		goto out;
353
354	ret = filemap_splice_read(in, ppos, pipe, len, flags);
355out:
356	up_read(&inode->i_rwsem);
357	return ret;
358}
359
360static ssize_t orangefs_file_write_iter(struct kiocb *iocb,
361    struct iov_iter *iter)
362{
363	int ret;
364	orangefs_stats.writes++;
365
366	if (iocb->ki_pos > i_size_read(file_inode(iocb->ki_filp))) {
367		ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp));
368		if (ret)
369			return ret;
370	}
371
372	ret = generic_file_write_iter(iocb, iter);
373	return ret;
374}
375
376static vm_fault_t orangefs_fault(struct vm_fault *vmf)
377{
378	struct file *file = vmf->vma->vm_file;
379	int ret;
380	ret = orangefs_inode_getattr(file->f_mapping->host,
381	    ORANGEFS_GETATTR_SIZE);
382	if (ret == -ESTALE)
383		ret = -EIO;
384	if (ret) {
385		gossip_err("%s: orangefs_inode_getattr failed, "
386		    "ret:%d:.\n", __func__, ret);
387		return VM_FAULT_SIGBUS;
388	}
389	return filemap_fault(vmf);
390}
391
392static const struct vm_operations_struct orangefs_file_vm_ops = {
393	.fault = orangefs_fault,
394	.map_pages = filemap_map_pages,
395	.page_mkwrite = orangefs_page_mkwrite,
396};
397
398/*
399 * Memory map a region of a file.
400 */
401static int orangefs_file_mmap(struct file *file, struct vm_area_struct *vma)
402{
403	int ret;
404
405	ret = orangefs_revalidate_mapping(file_inode(file));
406	if (ret)
407		return ret;
408
409	gossip_debug(GOSSIP_FILE_DEBUG,
410		     "orangefs_file_mmap: called on %pD\n", file);
411
412	/* set the sequential readahead hint */
413	vm_flags_mod(vma, VM_SEQ_READ, VM_RAND_READ);
 
414
415	file_accessed(file);
416	vma->vm_ops = &orangefs_file_vm_ops;
417	return 0;
418}
419
420#define mapping_nrpages(idata) ((idata)->nrpages)
421
422/*
423 * Called to notify the module that there are no more references to
424 * this file (i.e. no processes have it open).
425 *
426 * \note Not called when each file is closed.
427 */
428static int orangefs_file_release(struct inode *inode, struct file *file)
429{
430	gossip_debug(GOSSIP_FILE_DEBUG,
431		     "orangefs_file_release: called on %pD\n",
432		     file);
433
434	/*
435	 * remove all associated inode pages from the page cache and
436	 * readahead cache (if any); this forces an expensive refresh of
437	 * data for the next caller of mmap (or 'get_block' accesses)
438	 */
439	if (mapping_nrpages(file->f_mapping)) {
 
 
440		if (orangefs_features & ORANGEFS_FEATURE_READAHEAD) {
441			gossip_debug(GOSSIP_INODE_DEBUG,
442			    "calling flush_racache on %pU\n",
443			    get_khandle_from_ino(inode));
444			flush_racache(inode);
445			gossip_debug(GOSSIP_INODE_DEBUG,
446			    "flush_racache finished\n");
447		}
448
449	}
450	return 0;
451}
452
453/*
454 * Push all data for a specific file onto permanent storage.
455 */
456static int orangefs_fsync(struct file *file,
457		       loff_t start,
458		       loff_t end,
459		       int datasync)
460{
461	int ret;
462	struct orangefs_inode_s *orangefs_inode =
463		ORANGEFS_I(file_inode(file));
464	struct orangefs_kernel_op_s *new_op = NULL;
465
466	ret = filemap_write_and_wait_range(file_inode(file)->i_mapping,
467	    start, end);
468	if (ret < 0)
469		return ret;
470
471	new_op = op_alloc(ORANGEFS_VFS_OP_FSYNC);
472	if (!new_op)
473		return -ENOMEM;
474	new_op->upcall.req.fsync.refn = orangefs_inode->refn;
475
476	ret = service_operation(new_op,
477			"orangefs_fsync",
478			get_interruptible_flag(file_inode(file)));
479
480	gossip_debug(GOSSIP_FILE_DEBUG,
481		     "orangefs_fsync got return value of %d\n",
482		     ret);
483
484	op_release(new_op);
485	return ret;
486}
487
488/*
489 * Change the file pointer position for an instance of an open file.
490 *
491 * \note If .llseek is overriden, we must acquire lock as described in
492 *       Documentation/filesystems/locking.rst.
493 *
494 * Future upgrade could support SEEK_DATA and SEEK_HOLE but would
495 * require much changes to the FS
496 */
497static loff_t orangefs_file_llseek(struct file *file, loff_t offset, int origin)
498{
499	int ret = -EINVAL;
500	struct inode *inode = file_inode(file);
501
502	if (origin == SEEK_END) {
503		/*
504		 * revalidate the inode's file size.
505		 * NOTE: We are only interested in file size here,
506		 * so we set mask accordingly.
507		 */
508		ret = orangefs_inode_getattr(file->f_mapping->host,
509		    ORANGEFS_GETATTR_SIZE);
510		if (ret == -ESTALE)
511			ret = -EIO;
512		if (ret) {
513			gossip_debug(GOSSIP_FILE_DEBUG,
514				     "%s:%s:%d calling make bad inode\n",
515				     __FILE__,
516				     __func__,
517				     __LINE__);
518			return ret;
519		}
520	}
521
522	gossip_debug(GOSSIP_FILE_DEBUG,
523		     "orangefs_file_llseek: offset is %ld | origin is %d"
524		     " | inode size is %lu\n",
525		     (long)offset,
526		     origin,
527		     (unsigned long)i_size_read(inode));
528
529	return generic_file_llseek(file, offset, origin);
530}
531
532/*
533 * Support local locks (locks that only this kernel knows about)
534 * if Orangefs was mounted -o local_lock.
535 */
536static int orangefs_lock(struct file *filp, int cmd, struct file_lock *fl)
537{
538	int rc = -EINVAL;
539
540	if (ORANGEFS_SB(file_inode(filp)->i_sb)->flags & ORANGEFS_OPT_LOCAL_LOCK) {
541		if (cmd == F_GETLK) {
542			rc = 0;
543			posix_test_lock(filp, fl);
544		} else {
545			rc = posix_lock_file(filp, fl, NULL);
546		}
547	}
548
549	return rc;
550}
551
552static int orangefs_flush(struct file *file, fl_owner_t id)
553{
554	/*
555	 * This is vfs_fsync_range(file, 0, LLONG_MAX, 0) without the
556	 * service_operation in orangefs_fsync.
557	 *
558	 * Do not send fsync to OrangeFS server on a close.  Do send fsync
559	 * on an explicit fsync call.  This duplicates historical OrangeFS
560	 * behavior.
561	 */
562	int r;
563
564	r = filemap_write_and_wait_range(file->f_mapping, 0, LLONG_MAX);
565	if (r > 0)
566		return 0;
567	else
568		return r;
569}
570
571/** ORANGEFS implementation of VFS file operations */
572const struct file_operations orangefs_file_operations = {
573	.llseek		= orangefs_file_llseek,
574	.read_iter	= orangefs_file_read_iter,
575	.write_iter	= orangefs_file_write_iter,
576	.lock		= orangefs_lock,
577	.mmap		= orangefs_file_mmap,
578	.open		= generic_file_open,
579	.splice_read    = orangefs_file_splice_read,
580	.splice_write   = iter_file_splice_write,
581	.flush		= orangefs_flush,
582	.release	= orangefs_file_release,
583	.fsync		= orangefs_fsync,
584};
v5.14.15
  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
 19static 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 */
 48ssize_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,
 51	int *index_return, struct file *file)
 52{
 53	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
 54	struct orangefs_khandle *handle = &orangefs_inode->refn.khandle;
 55	struct orangefs_kernel_op_s *new_op = NULL;
 56	int buffer_index;
 57	ssize_t ret;
 58	size_t copy_amount;
 59	int open_for_read;
 60	int open_for_write;
 61
 62	new_op = op_alloc(ORANGEFS_VFS_OP_FILE_IO);
 63	if (!new_op)
 64		return -ENOMEM;
 65
 66	/* synchronous I/O */
 67	new_op->upcall.req.io.readahead_size = readahead_size;
 68	new_op->upcall.req.io.io_type = type;
 69	new_op->upcall.req.io.refn = orangefs_inode->refn;
 70
 71populate_shared_memory:
 72	/* get a shared buffer index */
 73	buffer_index = orangefs_bufmap_get();
 74	if (buffer_index < 0) {
 75		ret = buffer_index;
 76		gossip_debug(GOSSIP_FILE_DEBUG,
 77			     "%s: orangefs_bufmap_get failure (%zd)\n",
 78			     __func__, ret);
 79		goto out;
 80	}
 81	gossip_debug(GOSSIP_FILE_DEBUG,
 82		     "%s(%pU): GET op %p -> buffer_index %d\n",
 83		     __func__,
 84		     handle,
 85		     new_op,
 86		     buffer_index);
 87
 88	new_op->uses_shared_memory = 1;
 89	new_op->upcall.req.io.buf_index = buffer_index;
 90	new_op->upcall.req.io.count = total_size;
 91	new_op->upcall.req.io.offset = *offset;
 92	if (type == ORANGEFS_IO_WRITE && wr) {
 93		new_op->upcall.uid = from_kuid(&init_user_ns, wr->uid);
 94		new_op->upcall.gid = from_kgid(&init_user_ns, wr->gid);
 95	}
 96	/*
 97	 * Orangefs has no open, and orangefs checks file permissions
 98	 * on each file access. Posix requires that file permissions
 99	 * be checked on open and nowhere else. Orangefs-through-the-kernel
100	 * needs to seem posix compliant.
101	 *
102	 * The VFS opens files, even if the filesystem provides no
103	 * method. We can see if a file was successfully opened for
104	 * read and or for write by looking at file->f_mode.
105	 *
106	 * When writes are flowing from the page cache, file is no
107	 * longer available. We can trust the VFS to have checked
108	 * file->f_mode before writing to the page cache.
109	 *
110	 * The mode of a file might change between when it is opened
111	 * and IO commences, or it might be created with an arbitrary mode.
112	 *
113	 * We'll make sure we don't hit EACCES during the IO stage by
114	 * using UID 0. Some of the time we have access without changing
115	 * to UID 0 - how to check?
116	 */
117	if (file) {
118		open_for_write = file->f_mode & FMODE_WRITE;
119		open_for_read = file->f_mode & FMODE_READ;
120	} else {
121		open_for_write = 1;
122		open_for_read = 0; /* not relevant? */
123	}
124	if ((type == ORANGEFS_IO_WRITE) && open_for_write)
125		new_op->upcall.uid = 0;
126	if ((type == ORANGEFS_IO_READ) && open_for_read)
127		new_op->upcall.uid = 0;
128
129	gossip_debug(GOSSIP_FILE_DEBUG,
130		     "%s(%pU): offset: %llu total_size: %zd\n",
131		     __func__,
132		     handle,
133		     llu(*offset),
134		     total_size);
135	/*
136	 * Stage 1: copy the buffers into client-core's address space
137	 */
138	if (type == ORANGEFS_IO_WRITE && total_size) {
139		ret = orangefs_bufmap_copy_from_iovec(iter, buffer_index,
140		    total_size);
141		if (ret < 0) {
142			gossip_err("%s: Failed to copy-in buffers. Please make sure that the pvfs2-client is running. %ld\n",
143			    __func__, (long)ret);
144			goto out;
145		}
146	}
147
148	gossip_debug(GOSSIP_FILE_DEBUG,
149		     "%s(%pU): Calling post_io_request with tag (%llu)\n",
150		     __func__,
151		     handle,
152		     llu(new_op->tag));
153
154	/* Stage 2: Service the I/O operation */
155	ret = service_operation(new_op,
156				type == ORANGEFS_IO_WRITE ?
157					"file_write" :
158					"file_read",
159				get_interruptible_flag(inode));
160
161	/*
162	 * If service_operation() returns -EAGAIN #and# the operation was
163	 * purged from orangefs_request_list or htable_ops_in_progress, then
164	 * we know that the client was restarted, causing the shared memory
165	 * area to be wiped clean.  To restart a  write operation in this
166	 * case, we must re-copy the data from the user's iovec to a NEW
167	 * shared memory location. To restart a read operation, we must get
168	 * a new shared memory location.
169	 */
170	if (ret == -EAGAIN && op_state_purged(new_op)) {
171		orangefs_bufmap_put(buffer_index);
172		if (type == ORANGEFS_IO_WRITE)
173			iov_iter_revert(iter, total_size);
174		gossip_debug(GOSSIP_FILE_DEBUG,
175			     "%s:going to repopulate_shared_memory.\n",
176			     __func__);
177		goto populate_shared_memory;
178	}
179
180	if (ret < 0) {
181		if (ret == -EINTR) {
182			/*
183			 * We can't return EINTR if any data was written,
184			 * it's not POSIX. It is minimally acceptable
185			 * to give a partial write, the way NFS does.
186			 *
187			 * It would be optimal to return all or nothing,
188			 * but if a userspace write is bigger than
189			 * an IO buffer, and the interrupt occurs
190			 * between buffer writes, that would not be
191			 * possible.
192			 */
193			switch (new_op->op_state - OP_VFS_STATE_GIVEN_UP) {
194			/*
195			 * If the op was waiting when the interrupt
196			 * occurred, then the client-core did not
197			 * trigger the write.
198			 */
199			case OP_VFS_STATE_WAITING:
200				if (*offset == 0)
201					ret = -EINTR;
202				else
203					ret = 0;
204				break;
205			/*
206			 * If the op was in progress when the interrupt
207			 * occurred, then the client-core was able to
208			 * trigger the write.
209			 */
210			case OP_VFS_STATE_INPROGR:
211				if (type == ORANGEFS_IO_READ)
212					ret = -EINTR;
213				else
214					ret = total_size;
215				break;
216			default:
217				gossip_err("%s: unexpected op state :%d:.\n",
218					   __func__,
219					   new_op->op_state);
220				ret = 0;
221				break;
222			}
223			gossip_debug(GOSSIP_FILE_DEBUG,
224				     "%s: got EINTR, state:%d: %p\n",
225				     __func__,
226				     new_op->op_state,
227				     new_op);
228		} else {
229			gossip_err("%s: error in %s handle %pU, returning %zd\n",
230				__func__,
231				type == ORANGEFS_IO_READ ?
232					"read from" : "write to",
233				handle, ret);
234		}
235		if (orangefs_cancel_op_in_progress(new_op))
236			return ret;
237
238		goto out;
239	}
240
241	/*
242	 * Stage 3: Post copy buffers from client-core's address space
243	 */
244	if (type == ORANGEFS_IO_READ && new_op->downcall.resp.io.amt_complete) {
245		/*
246		 * NOTE: the iovector can either contain addresses which
247		 *       can futher be kernel-space or user-space addresses.
248		 *       or it can pointers to struct page's
249		 */
250
251		copy_amount = new_op->downcall.resp.io.amt_complete;
252
253		ret = orangefs_bufmap_copy_to_iovec(iter, buffer_index,
254			copy_amount);
255		if (ret < 0) {
256			gossip_err("%s: Failed to copy-out buffers. Please make sure that the pvfs2-client is running (%ld)\n",
257			    __func__, (long)ret);
258			goto out;
259		}
260	}
261	gossip_debug(GOSSIP_FILE_DEBUG,
262	    "%s(%pU): Amount %s, returned by the sys-io call:%d\n",
263	    __func__,
264	    handle,
265	    type == ORANGEFS_IO_READ ?  "read" : "written",
266	    (int)new_op->downcall.resp.io.amt_complete);
267
268	ret = new_op->downcall.resp.io.amt_complete;
269
270out:
271	if (buffer_index >= 0) {
272		orangefs_bufmap_put(buffer_index);
273		gossip_debug(GOSSIP_FILE_DEBUG,
274			"%s(%pU): PUT buffer_index %d\n",
275			__func__, handle, buffer_index);
276		buffer_index = -1;
277	}
278	op_release(new_op);
279	return ret;
280}
281
282int orangefs_revalidate_mapping(struct inode *inode)
283{
284	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
285	struct address_space *mapping = inode->i_mapping;
286	unsigned long *bitlock = &orangefs_inode->bitlock;
287	int ret;
288
289	while (1) {
290		ret = wait_on_bit(bitlock, 1, TASK_KILLABLE);
291		if (ret)
292			return ret;
293		spin_lock(&inode->i_lock);
294		if (test_bit(1, bitlock)) {
295			spin_unlock(&inode->i_lock);
296			continue;
297		}
298		if (!time_before(jiffies, orangefs_inode->mapping_time))
299			break;
300		spin_unlock(&inode->i_lock);
301		return 0;
302	}
303
304	set_bit(1, bitlock);
305	smp_wmb();
306	spin_unlock(&inode->i_lock);
307
308	unmap_mapping_range(mapping, 0, 0, 0);
309	ret = filemap_write_and_wait(mapping);
310	if (!ret)
311		ret = invalidate_inode_pages2(mapping);
312
313	orangefs_inode->mapping_time = jiffies +
314	    orangefs_cache_timeout_msecs*HZ/1000;
315
316	clear_bit(1, bitlock);
317	smp_mb__after_atomic();
318	wake_up_bit(bitlock, 1);
319
320	return ret;
321}
322
323static ssize_t orangefs_file_read_iter(struct kiocb *iocb,
324    struct iov_iter *iter)
325{
326	int ret;
327	orangefs_stats.reads++;
328
329	down_read(&file_inode(iocb->ki_filp)->i_rwsem);
330	ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp));
331	if (ret)
332		goto out;
333
334	ret = generic_file_read_iter(iocb, iter);
335out:
336	up_read(&file_inode(iocb->ki_filp)->i_rwsem);
337	return ret;
338}
339
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
340static ssize_t orangefs_file_write_iter(struct kiocb *iocb,
341    struct iov_iter *iter)
342{
343	int ret;
344	orangefs_stats.writes++;
345
346	if (iocb->ki_pos > i_size_read(file_inode(iocb->ki_filp))) {
347		ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp));
348		if (ret)
349			return ret;
350	}
351
352	ret = generic_file_write_iter(iocb, iter);
353	return ret;
354}
355
356static vm_fault_t orangefs_fault(struct vm_fault *vmf)
357{
358	struct file *file = vmf->vma->vm_file;
359	int ret;
360	ret = orangefs_inode_getattr(file->f_mapping->host,
361	    ORANGEFS_GETATTR_SIZE);
362	if (ret == -ESTALE)
363		ret = -EIO;
364	if (ret) {
365		gossip_err("%s: orangefs_inode_getattr failed, "
366		    "ret:%d:.\n", __func__, ret);
367		return VM_FAULT_SIGBUS;
368	}
369	return filemap_fault(vmf);
370}
371
372static const struct vm_operations_struct orangefs_file_vm_ops = {
373	.fault = orangefs_fault,
374	.map_pages = filemap_map_pages,
375	.page_mkwrite = orangefs_page_mkwrite,
376};
377
378/*
379 * Memory map a region of a file.
380 */
381static int orangefs_file_mmap(struct file *file, struct vm_area_struct *vma)
382{
383	int ret;
384
385	ret = orangefs_revalidate_mapping(file_inode(file));
386	if (ret)
387		return ret;
388
389	gossip_debug(GOSSIP_FILE_DEBUG,
390		     "orangefs_file_mmap: called on %pD\n", file);
391
392	/* set the sequential readahead hint */
393	vma->vm_flags |= VM_SEQ_READ;
394	vma->vm_flags &= ~VM_RAND_READ;
395
396	file_accessed(file);
397	vma->vm_ops = &orangefs_file_vm_ops;
398	return 0;
399}
400
401#define mapping_nrpages(idata) ((idata)->nrpages)
402
403/*
404 * Called to notify the module that there are no more references to
405 * this file (i.e. no processes have it open).
406 *
407 * \note Not called when each file is closed.
408 */
409static int orangefs_file_release(struct inode *inode, struct file *file)
410{
411	gossip_debug(GOSSIP_FILE_DEBUG,
412		     "orangefs_file_release: called on %pD\n",
413		     file);
414
415	/*
416	 * remove all associated inode pages from the page cache and
417	 * readahead cache (if any); this forces an expensive refresh of
418	 * data for the next caller of mmap (or 'get_block' accesses)
419	 */
420	if (file_inode(file) &&
421	    file_inode(file)->i_mapping &&
422	    mapping_nrpages(&file_inode(file)->i_data)) {
423		if (orangefs_features & ORANGEFS_FEATURE_READAHEAD) {
424			gossip_debug(GOSSIP_INODE_DEBUG,
425			    "calling flush_racache on %pU\n",
426			    get_khandle_from_ino(inode));
427			flush_racache(inode);
428			gossip_debug(GOSSIP_INODE_DEBUG,
429			    "flush_racache finished\n");
430		}
431
432	}
433	return 0;
434}
435
436/*
437 * Push all data for a specific file onto permanent storage.
438 */
439static int orangefs_fsync(struct file *file,
440		       loff_t start,
441		       loff_t end,
442		       int datasync)
443{
444	int ret;
445	struct orangefs_inode_s *orangefs_inode =
446		ORANGEFS_I(file_inode(file));
447	struct orangefs_kernel_op_s *new_op = NULL;
448
449	ret = filemap_write_and_wait_range(file_inode(file)->i_mapping,
450	    start, end);
451	if (ret < 0)
452		return ret;
453
454	new_op = op_alloc(ORANGEFS_VFS_OP_FSYNC);
455	if (!new_op)
456		return -ENOMEM;
457	new_op->upcall.req.fsync.refn = orangefs_inode->refn;
458
459	ret = service_operation(new_op,
460			"orangefs_fsync",
461			get_interruptible_flag(file_inode(file)));
462
463	gossip_debug(GOSSIP_FILE_DEBUG,
464		     "orangefs_fsync got return value of %d\n",
465		     ret);
466
467	op_release(new_op);
468	return ret;
469}
470
471/*
472 * Change the file pointer position for an instance of an open file.
473 *
474 * \note If .llseek is overriden, we must acquire lock as described in
475 *       Documentation/filesystems/locking.rst.
476 *
477 * Future upgrade could support SEEK_DATA and SEEK_HOLE but would
478 * require much changes to the FS
479 */
480static loff_t orangefs_file_llseek(struct file *file, loff_t offset, int origin)
481{
482	int ret = -EINVAL;
483	struct inode *inode = file_inode(file);
484
485	if (origin == SEEK_END) {
486		/*
487		 * revalidate the inode's file size.
488		 * NOTE: We are only interested in file size here,
489		 * so we set mask accordingly.
490		 */
491		ret = orangefs_inode_getattr(file->f_mapping->host,
492		    ORANGEFS_GETATTR_SIZE);
493		if (ret == -ESTALE)
494			ret = -EIO;
495		if (ret) {
496			gossip_debug(GOSSIP_FILE_DEBUG,
497				     "%s:%s:%d calling make bad inode\n",
498				     __FILE__,
499				     __func__,
500				     __LINE__);
501			return ret;
502		}
503	}
504
505	gossip_debug(GOSSIP_FILE_DEBUG,
506		     "orangefs_file_llseek: offset is %ld | origin is %d"
507		     " | inode size is %lu\n",
508		     (long)offset,
509		     origin,
510		     (unsigned long)i_size_read(inode));
511
512	return generic_file_llseek(file, offset, origin);
513}
514
515/*
516 * Support local locks (locks that only this kernel knows about)
517 * if Orangefs was mounted -o local_lock.
518 */
519static int orangefs_lock(struct file *filp, int cmd, struct file_lock *fl)
520{
521	int rc = -EINVAL;
522
523	if (ORANGEFS_SB(file_inode(filp)->i_sb)->flags & ORANGEFS_OPT_LOCAL_LOCK) {
524		if (cmd == F_GETLK) {
525			rc = 0;
526			posix_test_lock(filp, fl);
527		} else {
528			rc = posix_lock_file(filp, fl, NULL);
529		}
530	}
531
532	return rc;
533}
534
535static int orangefs_flush(struct file *file, fl_owner_t id)
536{
537	/*
538	 * This is vfs_fsync_range(file, 0, LLONG_MAX, 0) without the
539	 * service_operation in orangefs_fsync.
540	 *
541	 * Do not send fsync to OrangeFS server on a close.  Do send fsync
542	 * on an explicit fsync call.  This duplicates historical OrangeFS
543	 * behavior.
544	 */
545	int r;
546
547	r = filemap_write_and_wait_range(file->f_mapping, 0, LLONG_MAX);
548	if (r > 0)
549		return 0;
550	else
551		return r;
552}
553
554/** ORANGEFS implementation of VFS file operations */
555const struct file_operations orangefs_file_operations = {
556	.llseek		= orangefs_file_llseek,
557	.read_iter	= orangefs_file_read_iter,
558	.write_iter	= orangefs_file_write_iter,
559	.lock		= orangefs_lock,
560	.mmap		= orangefs_file_mmap,
561	.open		= generic_file_open,
562	.splice_read    = generic_file_splice_read,
563	.splice_write   = iter_file_splice_write,
564	.flush		= orangefs_flush,
565	.release	= orangefs_file_release,
566	.fsync		= orangefs_fsync,
567};