xref: /openbmc/linux/fs/f2fs/file.c (revision 6bacf52fb58aeb3e89d9a62970b85a5570aa8ace)
1 /*
2  * fs/f2fs/file.c
3  *
4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5  *             http://www.samsung.com/
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/fs.h>
12 #include <linux/f2fs_fs.h>
13 #include <linux/stat.h>
14 #include <linux/buffer_head.h>
15 #include <linux/writeback.h>
16 #include <linux/blkdev.h>
17 #include <linux/falloc.h>
18 #include <linux/types.h>
19 #include <linux/compat.h>
20 #include <linux/uaccess.h>
21 #include <linux/mount.h>
22 
23 #include "f2fs.h"
24 #include "node.h"
25 #include "segment.h"
26 #include "xattr.h"
27 #include "acl.h"
28 #include <trace/events/f2fs.h>
29 
30 static int f2fs_vm_page_mkwrite(struct vm_area_struct *vma,
31 						struct vm_fault *vmf)
32 {
33 	struct page *page = vmf->page;
34 	struct inode *inode = file_inode(vma->vm_file);
35 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
36 	struct dnode_of_data dn;
37 	int err;
38 
39 	f2fs_balance_fs(sbi);
40 
41 	sb_start_pagefault(inode->i_sb);
42 
43 	/* block allocation */
44 	f2fs_lock_op(sbi);
45 	set_new_dnode(&dn, inode, NULL, NULL, 0);
46 	err = f2fs_reserve_block(&dn, page->index);
47 	f2fs_unlock_op(sbi);
48 	if (err)
49 		goto out;
50 
51 	file_update_time(vma->vm_file);
52 	lock_page(page);
53 	if (unlikely(page->mapping != inode->i_mapping ||
54 			page_offset(page) > i_size_read(inode) ||
55 			!PageUptodate(page))) {
56 		unlock_page(page);
57 		err = -EFAULT;
58 		goto out;
59 	}
60 
61 	/*
62 	 * check to see if the page is mapped already (no holes)
63 	 */
64 	if (PageMappedToDisk(page))
65 		goto mapped;
66 
67 	/* page is wholly or partially inside EOF */
68 	if (((page->index + 1) << PAGE_CACHE_SHIFT) > i_size_read(inode)) {
69 		unsigned offset;
70 		offset = i_size_read(inode) & ~PAGE_CACHE_MASK;
71 		zero_user_segment(page, offset, PAGE_CACHE_SIZE);
72 	}
73 	set_page_dirty(page);
74 	SetPageUptodate(page);
75 
76 	trace_f2fs_vm_page_mkwrite(page, DATA);
77 mapped:
78 	/* fill the page */
79 	wait_on_page_writeback(page);
80 out:
81 	sb_end_pagefault(inode->i_sb);
82 	return block_page_mkwrite_return(err);
83 }
84 
85 static const struct vm_operations_struct f2fs_file_vm_ops = {
86 	.fault		= filemap_fault,
87 	.page_mkwrite	= f2fs_vm_page_mkwrite,
88 	.remap_pages	= generic_file_remap_pages,
89 };
90 
91 static int get_parent_ino(struct inode *inode, nid_t *pino)
92 {
93 	struct dentry *dentry;
94 
95 	inode = igrab(inode);
96 	dentry = d_find_any_alias(inode);
97 	iput(inode);
98 	if (!dentry)
99 		return 0;
100 
101 	if (update_dent_inode(inode, &dentry->d_name)) {
102 		dput(dentry);
103 		return 0;
104 	}
105 
106 	*pino = parent_ino(dentry);
107 	dput(dentry);
108 	return 1;
109 }
110 
111 int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
112 {
113 	struct inode *inode = file->f_mapping->host;
114 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
115 	int ret = 0;
116 	bool need_cp = false;
117 	struct writeback_control wbc = {
118 		.sync_mode = WB_SYNC_ALL,
119 		.nr_to_write = LONG_MAX,
120 		.for_reclaim = 0,
121 	};
122 
123 	if (unlikely(f2fs_readonly(inode->i_sb)))
124 		return 0;
125 
126 	trace_f2fs_sync_file_enter(inode);
127 	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
128 	if (ret) {
129 		trace_f2fs_sync_file_exit(inode, need_cp, datasync, ret);
130 		return ret;
131 	}
132 
133 	/* guarantee free sections for fsync */
134 	f2fs_balance_fs(sbi);
135 
136 	mutex_lock(&inode->i_mutex);
137 
138 	/*
139 	 * Both of fdatasync() and fsync() are able to be recovered from
140 	 * sudden-power-off.
141 	 */
142 	if (!S_ISREG(inode->i_mode) || inode->i_nlink != 1)
143 		need_cp = true;
144 	else if (file_wrong_pino(inode))
145 		need_cp = true;
146 	else if (!space_for_roll_forward(sbi))
147 		need_cp = true;
148 	else if (!is_checkpointed_node(sbi, F2FS_I(inode)->i_pino))
149 		need_cp = true;
150 	else if (F2FS_I(inode)->xattr_ver == cur_cp_version(F2FS_CKPT(sbi)))
151 		need_cp = true;
152 
153 	if (need_cp) {
154 		nid_t pino;
155 
156 		F2FS_I(inode)->xattr_ver = 0;
157 
158 		/* all the dirty node pages should be flushed for POR */
159 		ret = f2fs_sync_fs(inode->i_sb, 1);
160 		if (file_wrong_pino(inode) && inode->i_nlink == 1 &&
161 					get_parent_ino(inode, &pino)) {
162 			F2FS_I(inode)->i_pino = pino;
163 			file_got_pino(inode);
164 			mark_inode_dirty_sync(inode);
165 			ret = f2fs_write_inode(inode, NULL);
166 			if (ret)
167 				goto out;
168 		}
169 	} else {
170 		/* if there is no written node page, write its inode page */
171 		while (!sync_node_pages(sbi, inode->i_ino, &wbc)) {
172 			mark_inode_dirty_sync(inode);
173 			ret = f2fs_write_inode(inode, NULL);
174 			if (ret)
175 				goto out;
176 		}
177 		ret = wait_on_node_pages_writeback(sbi, inode->i_ino);
178 		if (ret)
179 			goto out;
180 		ret = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
181 	}
182 out:
183 	mutex_unlock(&inode->i_mutex);
184 	trace_f2fs_sync_file_exit(inode, need_cp, datasync, ret);
185 	return ret;
186 }
187 
188 static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma)
189 {
190 	file_accessed(file);
191 	vma->vm_ops = &f2fs_file_vm_ops;
192 	return 0;
193 }
194 
195 int truncate_data_blocks_range(struct dnode_of_data *dn, int count)
196 {
197 	int nr_free = 0, ofs = dn->ofs_in_node;
198 	struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
199 	struct f2fs_node *raw_node;
200 	__le32 *addr;
201 
202 	raw_node = F2FS_NODE(dn->node_page);
203 	addr = blkaddr_in_node(raw_node) + ofs;
204 
205 	for ( ; count > 0; count--, addr++, dn->ofs_in_node++) {
206 		block_t blkaddr = le32_to_cpu(*addr);
207 		if (blkaddr == NULL_ADDR)
208 			continue;
209 
210 		update_extent_cache(NULL_ADDR, dn);
211 		invalidate_blocks(sbi, blkaddr);
212 		nr_free++;
213 	}
214 	if (nr_free) {
215 		dec_valid_block_count(sbi, dn->inode, nr_free);
216 		set_page_dirty(dn->node_page);
217 		sync_inode_page(dn);
218 	}
219 	dn->ofs_in_node = ofs;
220 
221 	trace_f2fs_truncate_data_blocks_range(dn->inode, dn->nid,
222 					 dn->ofs_in_node, nr_free);
223 	return nr_free;
224 }
225 
226 void truncate_data_blocks(struct dnode_of_data *dn)
227 {
228 	truncate_data_blocks_range(dn, ADDRS_PER_BLOCK);
229 }
230 
231 static void truncate_partial_data_page(struct inode *inode, u64 from)
232 {
233 	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
234 	struct page *page;
235 
236 	if (!offset)
237 		return;
238 
239 	page = find_data_page(inode, from >> PAGE_CACHE_SHIFT, false);
240 	if (IS_ERR(page))
241 		return;
242 
243 	lock_page(page);
244 	if (unlikely(page->mapping != inode->i_mapping)) {
245 		f2fs_put_page(page, 1);
246 		return;
247 	}
248 	wait_on_page_writeback(page);
249 	zero_user(page, offset, PAGE_CACHE_SIZE - offset);
250 	set_page_dirty(page);
251 	f2fs_put_page(page, 1);
252 }
253 
254 static int truncate_blocks(struct inode *inode, u64 from)
255 {
256 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
257 	unsigned int blocksize = inode->i_sb->s_blocksize;
258 	struct dnode_of_data dn;
259 	pgoff_t free_from;
260 	int count = 0;
261 	int err;
262 
263 	trace_f2fs_truncate_blocks_enter(inode, from);
264 
265 	free_from = (pgoff_t)
266 			((from + blocksize - 1) >> (sbi->log_blocksize));
267 
268 	f2fs_lock_op(sbi);
269 	set_new_dnode(&dn, inode, NULL, NULL, 0);
270 	err = get_dnode_of_data(&dn, free_from, LOOKUP_NODE);
271 	if (err) {
272 		if (err == -ENOENT)
273 			goto free_next;
274 		f2fs_unlock_op(sbi);
275 		trace_f2fs_truncate_blocks_exit(inode, err);
276 		return err;
277 	}
278 
279 	if (IS_INODE(dn.node_page))
280 		count = ADDRS_PER_INODE(F2FS_I(inode));
281 	else
282 		count = ADDRS_PER_BLOCK;
283 
284 	count -= dn.ofs_in_node;
285 	f2fs_bug_on(count < 0);
286 
287 	if (dn.ofs_in_node || IS_INODE(dn.node_page)) {
288 		truncate_data_blocks_range(&dn, count);
289 		free_from += count;
290 	}
291 
292 	f2fs_put_dnode(&dn);
293 free_next:
294 	err = truncate_inode_blocks(inode, free_from);
295 	f2fs_unlock_op(sbi);
296 
297 	/* lastly zero out the first data page */
298 	truncate_partial_data_page(inode, from);
299 
300 	trace_f2fs_truncate_blocks_exit(inode, err);
301 	return err;
302 }
303 
304 void f2fs_truncate(struct inode *inode)
305 {
306 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
307 				S_ISLNK(inode->i_mode)))
308 		return;
309 
310 	trace_f2fs_truncate(inode);
311 
312 	if (!truncate_blocks(inode, i_size_read(inode))) {
313 		inode->i_mtime = inode->i_ctime = CURRENT_TIME;
314 		mark_inode_dirty(inode);
315 	}
316 }
317 
318 int f2fs_getattr(struct vfsmount *mnt,
319 			 struct dentry *dentry, struct kstat *stat)
320 {
321 	struct inode *inode = dentry->d_inode;
322 	generic_fillattr(inode, stat);
323 	stat->blocks <<= 3;
324 	return 0;
325 }
326 
327 #ifdef CONFIG_F2FS_FS_POSIX_ACL
328 static void __setattr_copy(struct inode *inode, const struct iattr *attr)
329 {
330 	struct f2fs_inode_info *fi = F2FS_I(inode);
331 	unsigned int ia_valid = attr->ia_valid;
332 
333 	if (ia_valid & ATTR_UID)
334 		inode->i_uid = attr->ia_uid;
335 	if (ia_valid & ATTR_GID)
336 		inode->i_gid = attr->ia_gid;
337 	if (ia_valid & ATTR_ATIME)
338 		inode->i_atime = timespec_trunc(attr->ia_atime,
339 						inode->i_sb->s_time_gran);
340 	if (ia_valid & ATTR_MTIME)
341 		inode->i_mtime = timespec_trunc(attr->ia_mtime,
342 						inode->i_sb->s_time_gran);
343 	if (ia_valid & ATTR_CTIME)
344 		inode->i_ctime = timespec_trunc(attr->ia_ctime,
345 						inode->i_sb->s_time_gran);
346 	if (ia_valid & ATTR_MODE) {
347 		umode_t mode = attr->ia_mode;
348 
349 		if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
350 			mode &= ~S_ISGID;
351 		set_acl_inode(fi, mode);
352 	}
353 }
354 #else
355 #define __setattr_copy setattr_copy
356 #endif
357 
358 int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
359 {
360 	struct inode *inode = dentry->d_inode;
361 	struct f2fs_inode_info *fi = F2FS_I(inode);
362 	int err;
363 
364 	err = inode_change_ok(inode, attr);
365 	if (err)
366 		return err;
367 
368 	if ((attr->ia_valid & ATTR_SIZE) &&
369 			attr->ia_size != i_size_read(inode)) {
370 		truncate_setsize(inode, attr->ia_size);
371 		f2fs_truncate(inode);
372 		f2fs_balance_fs(F2FS_SB(inode->i_sb));
373 	}
374 
375 	__setattr_copy(inode, attr);
376 
377 	if (attr->ia_valid & ATTR_MODE) {
378 		err = f2fs_acl_chmod(inode);
379 		if (err || is_inode_flag_set(fi, FI_ACL_MODE)) {
380 			inode->i_mode = fi->i_acl_mode;
381 			clear_inode_flag(fi, FI_ACL_MODE);
382 		}
383 	}
384 
385 	mark_inode_dirty(inode);
386 	return err;
387 }
388 
389 const struct inode_operations f2fs_file_inode_operations = {
390 	.getattr	= f2fs_getattr,
391 	.setattr	= f2fs_setattr,
392 	.get_acl	= f2fs_get_acl,
393 #ifdef CONFIG_F2FS_FS_XATTR
394 	.setxattr	= generic_setxattr,
395 	.getxattr	= generic_getxattr,
396 	.listxattr	= f2fs_listxattr,
397 	.removexattr	= generic_removexattr,
398 #endif
399 };
400 
401 static void fill_zero(struct inode *inode, pgoff_t index,
402 					loff_t start, loff_t len)
403 {
404 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
405 	struct page *page;
406 
407 	if (!len)
408 		return;
409 
410 	f2fs_balance_fs(sbi);
411 
412 	f2fs_lock_op(sbi);
413 	page = get_new_data_page(inode, NULL, index, false);
414 	f2fs_unlock_op(sbi);
415 
416 	if (!IS_ERR(page)) {
417 		wait_on_page_writeback(page);
418 		zero_user(page, start, len);
419 		set_page_dirty(page);
420 		f2fs_put_page(page, 1);
421 	}
422 }
423 
424 int truncate_hole(struct inode *inode, pgoff_t pg_start, pgoff_t pg_end)
425 {
426 	pgoff_t index;
427 	int err;
428 
429 	for (index = pg_start; index < pg_end; index++) {
430 		struct dnode_of_data dn;
431 
432 		set_new_dnode(&dn, inode, NULL, NULL, 0);
433 		err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
434 		if (err) {
435 			if (err == -ENOENT)
436 				continue;
437 			return err;
438 		}
439 
440 		if (dn.data_blkaddr != NULL_ADDR)
441 			truncate_data_blocks_range(&dn, 1);
442 		f2fs_put_dnode(&dn);
443 	}
444 	return 0;
445 }
446 
447 static int punch_hole(struct inode *inode, loff_t offset, loff_t len)
448 {
449 	pgoff_t pg_start, pg_end;
450 	loff_t off_start, off_end;
451 	int ret = 0;
452 
453 	pg_start = ((unsigned long long) offset) >> PAGE_CACHE_SHIFT;
454 	pg_end = ((unsigned long long) offset + len) >> PAGE_CACHE_SHIFT;
455 
456 	off_start = offset & (PAGE_CACHE_SIZE - 1);
457 	off_end = (offset + len) & (PAGE_CACHE_SIZE - 1);
458 
459 	if (pg_start == pg_end) {
460 		fill_zero(inode, pg_start, off_start,
461 						off_end - off_start);
462 	} else {
463 		if (off_start)
464 			fill_zero(inode, pg_start++, off_start,
465 					PAGE_CACHE_SIZE - off_start);
466 		if (off_end)
467 			fill_zero(inode, pg_end, 0, off_end);
468 
469 		if (pg_start < pg_end) {
470 			struct address_space *mapping = inode->i_mapping;
471 			loff_t blk_start, blk_end;
472 			struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
473 
474 			f2fs_balance_fs(sbi);
475 
476 			blk_start = pg_start << PAGE_CACHE_SHIFT;
477 			blk_end = pg_end << PAGE_CACHE_SHIFT;
478 			truncate_inode_pages_range(mapping, blk_start,
479 					blk_end - 1);
480 
481 			f2fs_lock_op(sbi);
482 			ret = truncate_hole(inode, pg_start, pg_end);
483 			f2fs_unlock_op(sbi);
484 		}
485 	}
486 
487 	return ret;
488 }
489 
490 static int expand_inode_data(struct inode *inode, loff_t offset,
491 					loff_t len, int mode)
492 {
493 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
494 	pgoff_t index, pg_start, pg_end;
495 	loff_t new_size = i_size_read(inode);
496 	loff_t off_start, off_end;
497 	int ret = 0;
498 
499 	ret = inode_newsize_ok(inode, (len + offset));
500 	if (ret)
501 		return ret;
502 
503 	pg_start = ((unsigned long long) offset) >> PAGE_CACHE_SHIFT;
504 	pg_end = ((unsigned long long) offset + len) >> PAGE_CACHE_SHIFT;
505 
506 	off_start = offset & (PAGE_CACHE_SIZE - 1);
507 	off_end = (offset + len) & (PAGE_CACHE_SIZE - 1);
508 
509 	for (index = pg_start; index <= pg_end; index++) {
510 		struct dnode_of_data dn;
511 
512 		f2fs_lock_op(sbi);
513 		set_new_dnode(&dn, inode, NULL, NULL, 0);
514 		ret = f2fs_reserve_block(&dn, index);
515 		f2fs_unlock_op(sbi);
516 		if (ret)
517 			break;
518 
519 		if (pg_start == pg_end)
520 			new_size = offset + len;
521 		else if (index == pg_start && off_start)
522 			new_size = (index + 1) << PAGE_CACHE_SHIFT;
523 		else if (index == pg_end)
524 			new_size = (index << PAGE_CACHE_SHIFT) + off_end;
525 		else
526 			new_size += PAGE_CACHE_SIZE;
527 	}
528 
529 	if (!(mode & FALLOC_FL_KEEP_SIZE) &&
530 		i_size_read(inode) < new_size) {
531 		i_size_write(inode, new_size);
532 		mark_inode_dirty(inode);
533 	}
534 
535 	return ret;
536 }
537 
538 static long f2fs_fallocate(struct file *file, int mode,
539 				loff_t offset, loff_t len)
540 {
541 	struct inode *inode = file_inode(file);
542 	long ret;
543 
544 	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
545 		return -EOPNOTSUPP;
546 
547 	if (mode & FALLOC_FL_PUNCH_HOLE)
548 		ret = punch_hole(inode, offset, len);
549 	else
550 		ret = expand_inode_data(inode, offset, len, mode);
551 
552 	if (!ret) {
553 		inode->i_mtime = inode->i_ctime = CURRENT_TIME;
554 		mark_inode_dirty(inode);
555 	}
556 	trace_f2fs_fallocate(inode, mode, offset, len, ret);
557 	return ret;
558 }
559 
560 #define F2FS_REG_FLMASK		(~(FS_DIRSYNC_FL | FS_TOPDIR_FL))
561 #define F2FS_OTHER_FLMASK	(FS_NODUMP_FL | FS_NOATIME_FL)
562 
563 static inline __u32 f2fs_mask_flags(umode_t mode, __u32 flags)
564 {
565 	if (S_ISDIR(mode))
566 		return flags;
567 	else if (S_ISREG(mode))
568 		return flags & F2FS_REG_FLMASK;
569 	else
570 		return flags & F2FS_OTHER_FLMASK;
571 }
572 
573 long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
574 {
575 	struct inode *inode = file_inode(filp);
576 	struct f2fs_inode_info *fi = F2FS_I(inode);
577 	unsigned int flags;
578 	int ret;
579 
580 	switch (cmd) {
581 	case F2FS_IOC_GETFLAGS:
582 		flags = fi->i_flags & FS_FL_USER_VISIBLE;
583 		return put_user(flags, (int __user *) arg);
584 	case F2FS_IOC_SETFLAGS:
585 	{
586 		unsigned int oldflags;
587 
588 		ret = mnt_want_write_file(filp);
589 		if (ret)
590 			return ret;
591 
592 		if (!inode_owner_or_capable(inode)) {
593 			ret = -EACCES;
594 			goto out;
595 		}
596 
597 		if (get_user(flags, (int __user *) arg)) {
598 			ret = -EFAULT;
599 			goto out;
600 		}
601 
602 		flags = f2fs_mask_flags(inode->i_mode, flags);
603 
604 		mutex_lock(&inode->i_mutex);
605 
606 		oldflags = fi->i_flags;
607 
608 		if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
609 			if (!capable(CAP_LINUX_IMMUTABLE)) {
610 				mutex_unlock(&inode->i_mutex);
611 				ret = -EPERM;
612 				goto out;
613 			}
614 		}
615 
616 		flags = flags & FS_FL_USER_MODIFIABLE;
617 		flags |= oldflags & ~FS_FL_USER_MODIFIABLE;
618 		fi->i_flags = flags;
619 		mutex_unlock(&inode->i_mutex);
620 
621 		f2fs_set_inode_flags(inode);
622 		inode->i_ctime = CURRENT_TIME;
623 		mark_inode_dirty(inode);
624 out:
625 		mnt_drop_write_file(filp);
626 		return ret;
627 	}
628 	default:
629 		return -ENOTTY;
630 	}
631 }
632 
633 #ifdef CONFIG_COMPAT
634 long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
635 {
636 	switch (cmd) {
637 	case F2FS_IOC32_GETFLAGS:
638 		cmd = F2FS_IOC_GETFLAGS;
639 		break;
640 	case F2FS_IOC32_SETFLAGS:
641 		cmd = F2FS_IOC_SETFLAGS;
642 		break;
643 	default:
644 		return -ENOIOCTLCMD;
645 	}
646 	return f2fs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
647 }
648 #endif
649 
650 const struct file_operations f2fs_file_operations = {
651 	.llseek		= generic_file_llseek,
652 	.read		= do_sync_read,
653 	.write		= do_sync_write,
654 	.aio_read	= generic_file_aio_read,
655 	.aio_write	= generic_file_aio_write,
656 	.open		= generic_file_open,
657 	.mmap		= f2fs_file_mmap,
658 	.fsync		= f2fs_sync_file,
659 	.fallocate	= f2fs_fallocate,
660 	.unlocked_ioctl	= f2fs_ioctl,
661 #ifdef CONFIG_COMPAT
662 	.compat_ioctl	= f2fs_compat_ioctl,
663 #endif
664 	.splice_read	= generic_file_splice_read,
665 	.splice_write	= generic_file_splice_write,
666 };
667