xref: /linux/fs/f2fs/file.c (revision 9ae9e2535d7dd1c21d6a7db1a7f2fc507a5e4080)
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/falloc.h>
17 #include <linux/types.h>
18 #include <linux/uaccess.h>
19 #include <linux/mount.h>
20 
21 #include "f2fs.h"
22 #include "node.h"
23 #include "segment.h"
24 #include "xattr.h"
25 #include "acl.h"
26 
27 static int f2fs_vm_page_mkwrite(struct vm_area_struct *vma,
28 						struct vm_fault *vmf)
29 {
30 	struct page *page = vmf->page;
31 	struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
32 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
33 	block_t old_blk_addr;
34 	struct dnode_of_data dn;
35 	int err;
36 
37 	f2fs_balance_fs(sbi);
38 
39 	sb_start_pagefault(inode->i_sb);
40 
41 	mutex_lock_op(sbi, DATA_NEW);
42 
43 	/* block allocation */
44 	set_new_dnode(&dn, inode, NULL, NULL, 0);
45 	err = get_dnode_of_data(&dn, page->index, 0);
46 	if (err) {
47 		mutex_unlock_op(sbi, DATA_NEW);
48 		goto out;
49 	}
50 
51 	old_blk_addr = dn.data_blkaddr;
52 
53 	if (old_blk_addr == NULL_ADDR) {
54 		err = reserve_new_block(&dn);
55 		if (err) {
56 			f2fs_put_dnode(&dn);
57 			mutex_unlock_op(sbi, DATA_NEW);
58 			goto out;
59 		}
60 	}
61 	f2fs_put_dnode(&dn);
62 
63 	mutex_unlock_op(sbi, DATA_NEW);
64 
65 	lock_page(page);
66 	if (page->mapping != inode->i_mapping ||
67 			page_offset(page) >= i_size_read(inode) ||
68 			!PageUptodate(page)) {
69 		unlock_page(page);
70 		err = -EFAULT;
71 		goto out;
72 	}
73 
74 	/*
75 	 * check to see if the page is mapped already (no holes)
76 	 */
77 	if (PageMappedToDisk(page))
78 		goto out;
79 
80 	/* fill the page */
81 	wait_on_page_writeback(page);
82 
83 	/* page is wholly or partially inside EOF */
84 	if (((page->index + 1) << PAGE_CACHE_SHIFT) > i_size_read(inode)) {
85 		unsigned offset;
86 		offset = i_size_read(inode) & ~PAGE_CACHE_MASK;
87 		zero_user_segment(page, offset, PAGE_CACHE_SIZE);
88 	}
89 	set_page_dirty(page);
90 	SetPageUptodate(page);
91 
92 	file_update_time(vma->vm_file);
93 out:
94 	sb_end_pagefault(inode->i_sb);
95 	return block_page_mkwrite_return(err);
96 }
97 
98 static const struct vm_operations_struct f2fs_file_vm_ops = {
99 	.fault		= filemap_fault,
100 	.page_mkwrite	= f2fs_vm_page_mkwrite,
101 	.remap_pages	= generic_file_remap_pages,
102 };
103 
104 static int need_to_sync_dir(struct f2fs_sb_info *sbi, struct inode *inode)
105 {
106 	struct dentry *dentry;
107 	nid_t pino;
108 
109 	inode = igrab(inode);
110 	dentry = d_find_any_alias(inode);
111 	if (!dentry) {
112 		iput(inode);
113 		return 0;
114 	}
115 	pino = dentry->d_parent->d_inode->i_ino;
116 	dput(dentry);
117 	iput(inode);
118 	return !is_checkpointed_node(sbi, pino);
119 }
120 
121 int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
122 {
123 	struct inode *inode = file->f_mapping->host;
124 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
125 	unsigned long long cur_version;
126 	int ret = 0;
127 	bool need_cp = false;
128 	struct writeback_control wbc = {
129 		.sync_mode = WB_SYNC_ALL,
130 		.nr_to_write = LONG_MAX,
131 		.for_reclaim = 0,
132 	};
133 
134 	if (inode->i_sb->s_flags & MS_RDONLY)
135 		return 0;
136 
137 	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
138 	if (ret)
139 		return ret;
140 
141 	/* guarantee free sections for fsync */
142 	f2fs_balance_fs(sbi);
143 
144 	mutex_lock(&inode->i_mutex);
145 
146 	if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
147 		goto out;
148 
149 	mutex_lock(&sbi->cp_mutex);
150 	cur_version = le64_to_cpu(F2FS_CKPT(sbi)->checkpoint_ver);
151 	mutex_unlock(&sbi->cp_mutex);
152 
153 	if (F2FS_I(inode)->data_version != cur_version &&
154 					!(inode->i_state & I_DIRTY))
155 		goto out;
156 	F2FS_I(inode)->data_version--;
157 
158 	if (!S_ISREG(inode->i_mode) || inode->i_nlink != 1)
159 		need_cp = true;
160 	if (is_inode_flag_set(F2FS_I(inode), FI_NEED_CP))
161 		need_cp = true;
162 	if (!space_for_roll_forward(sbi))
163 		need_cp = true;
164 	if (need_to_sync_dir(sbi, inode))
165 		need_cp = true;
166 
167 	if (need_cp) {
168 		/* all the dirty node pages should be flushed for POR */
169 		ret = f2fs_sync_fs(inode->i_sb, 1);
170 		clear_inode_flag(F2FS_I(inode), FI_NEED_CP);
171 	} else {
172 		/* if there is no written node page, write its inode page */
173 		while (!sync_node_pages(sbi, inode->i_ino, &wbc)) {
174 			ret = f2fs_write_inode(inode, NULL);
175 			if (ret)
176 				goto out;
177 		}
178 		filemap_fdatawait_range(sbi->node_inode->i_mapping,
179 							0, LONG_MAX);
180 	}
181 out:
182 	mutex_unlock(&inode->i_mutex);
183 	return ret;
184 }
185 
186 static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma)
187 {
188 	file_accessed(file);
189 	vma->vm_ops = &f2fs_file_vm_ops;
190 	return 0;
191 }
192 
193 static int truncate_data_blocks_range(struct dnode_of_data *dn, int count)
194 {
195 	int nr_free = 0, ofs = dn->ofs_in_node;
196 	struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
197 	struct f2fs_node *raw_node;
198 	__le32 *addr;
199 
200 	raw_node = page_address(dn->node_page);
201 	addr = blkaddr_in_node(raw_node) + ofs;
202 
203 	for ( ; count > 0; count--, addr++, dn->ofs_in_node++) {
204 		block_t blkaddr = le32_to_cpu(*addr);
205 		if (blkaddr == NULL_ADDR)
206 			continue;
207 
208 		update_extent_cache(NULL_ADDR, dn);
209 		invalidate_blocks(sbi, blkaddr);
210 		dec_valid_block_count(sbi, dn->inode, 1);
211 		nr_free++;
212 	}
213 	if (nr_free) {
214 		set_page_dirty(dn->node_page);
215 		sync_inode_page(dn);
216 	}
217 	dn->ofs_in_node = ofs;
218 	return nr_free;
219 }
220 
221 void truncate_data_blocks(struct dnode_of_data *dn)
222 {
223 	truncate_data_blocks_range(dn, ADDRS_PER_BLOCK);
224 }
225 
226 static void truncate_partial_data_page(struct inode *inode, u64 from)
227 {
228 	unsigned offset = from & (PAGE_CACHE_SIZE - 1);
229 	struct page *page;
230 
231 	if (!offset)
232 		return;
233 
234 	page = find_data_page(inode, from >> PAGE_CACHE_SHIFT);
235 	if (IS_ERR(page))
236 		return;
237 
238 	lock_page(page);
239 	wait_on_page_writeback(page);
240 	zero_user(page, offset, PAGE_CACHE_SIZE - offset);
241 	set_page_dirty(page);
242 	f2fs_put_page(page, 1);
243 }
244 
245 static int truncate_blocks(struct inode *inode, u64 from)
246 {
247 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
248 	unsigned int blocksize = inode->i_sb->s_blocksize;
249 	struct dnode_of_data dn;
250 	pgoff_t free_from;
251 	int count = 0;
252 	int err;
253 
254 	free_from = (pgoff_t)
255 			((from + blocksize - 1) >> (sbi->log_blocksize));
256 
257 	mutex_lock_op(sbi, DATA_TRUNC);
258 
259 	set_new_dnode(&dn, inode, NULL, NULL, 0);
260 	err = get_dnode_of_data(&dn, free_from, RDONLY_NODE);
261 	if (err) {
262 		if (err == -ENOENT)
263 			goto free_next;
264 		mutex_unlock_op(sbi, DATA_TRUNC);
265 		return err;
266 	}
267 
268 	if (IS_INODE(dn.node_page))
269 		count = ADDRS_PER_INODE;
270 	else
271 		count = ADDRS_PER_BLOCK;
272 
273 	count -= dn.ofs_in_node;
274 	BUG_ON(count < 0);
275 	if (dn.ofs_in_node || IS_INODE(dn.node_page)) {
276 		truncate_data_blocks_range(&dn, count);
277 		free_from += count;
278 	}
279 
280 	f2fs_put_dnode(&dn);
281 free_next:
282 	err = truncate_inode_blocks(inode, free_from);
283 	mutex_unlock_op(sbi, DATA_TRUNC);
284 
285 	/* lastly zero out the first data page */
286 	truncate_partial_data_page(inode, from);
287 
288 	return err;
289 }
290 
291 void f2fs_truncate(struct inode *inode)
292 {
293 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
294 				S_ISLNK(inode->i_mode)))
295 		return;
296 
297 	if (!truncate_blocks(inode, i_size_read(inode))) {
298 		inode->i_mtime = inode->i_ctime = CURRENT_TIME;
299 		mark_inode_dirty(inode);
300 	}
301 
302 	f2fs_balance_fs(F2FS_SB(inode->i_sb));
303 }
304 
305 static int f2fs_getattr(struct vfsmount *mnt,
306 			 struct dentry *dentry, struct kstat *stat)
307 {
308 	struct inode *inode = dentry->d_inode;
309 	generic_fillattr(inode, stat);
310 	stat->blocks <<= 3;
311 	return 0;
312 }
313 
314 #ifdef CONFIG_F2FS_FS_POSIX_ACL
315 static void __setattr_copy(struct inode *inode, const struct iattr *attr)
316 {
317 	struct f2fs_inode_info *fi = F2FS_I(inode);
318 	unsigned int ia_valid = attr->ia_valid;
319 
320 	if (ia_valid & ATTR_UID)
321 		inode->i_uid = attr->ia_uid;
322 	if (ia_valid & ATTR_GID)
323 		inode->i_gid = attr->ia_gid;
324 	if (ia_valid & ATTR_ATIME)
325 		inode->i_atime = timespec_trunc(attr->ia_atime,
326 						inode->i_sb->s_time_gran);
327 	if (ia_valid & ATTR_MTIME)
328 		inode->i_mtime = timespec_trunc(attr->ia_mtime,
329 						inode->i_sb->s_time_gran);
330 	if (ia_valid & ATTR_CTIME)
331 		inode->i_ctime = timespec_trunc(attr->ia_ctime,
332 						inode->i_sb->s_time_gran);
333 	if (ia_valid & ATTR_MODE) {
334 		umode_t mode = attr->ia_mode;
335 
336 		if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
337 			mode &= ~S_ISGID;
338 		set_acl_inode(fi, mode);
339 	}
340 }
341 #else
342 #define __setattr_copy setattr_copy
343 #endif
344 
345 int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
346 {
347 	struct inode *inode = dentry->d_inode;
348 	struct f2fs_inode_info *fi = F2FS_I(inode);
349 	int err;
350 
351 	err = inode_change_ok(inode, attr);
352 	if (err)
353 		return err;
354 
355 	if ((attr->ia_valid & ATTR_SIZE) &&
356 			attr->ia_size != i_size_read(inode)) {
357 		truncate_setsize(inode, attr->ia_size);
358 		f2fs_truncate(inode);
359 	}
360 
361 	__setattr_copy(inode, attr);
362 
363 	if (attr->ia_valid & ATTR_MODE) {
364 		err = f2fs_acl_chmod(inode);
365 		if (err || is_inode_flag_set(fi, FI_ACL_MODE)) {
366 			inode->i_mode = fi->i_acl_mode;
367 			clear_inode_flag(fi, FI_ACL_MODE);
368 		}
369 	}
370 
371 	mark_inode_dirty(inode);
372 	return err;
373 }
374 
375 const struct inode_operations f2fs_file_inode_operations = {
376 	.getattr	= f2fs_getattr,
377 	.setattr	= f2fs_setattr,
378 	.get_acl	= f2fs_get_acl,
379 #ifdef CONFIG_F2FS_FS_XATTR
380 	.setxattr	= generic_setxattr,
381 	.getxattr	= generic_getxattr,
382 	.listxattr	= f2fs_listxattr,
383 	.removexattr	= generic_removexattr,
384 #endif
385 };
386 
387 static void fill_zero(struct inode *inode, pgoff_t index,
388 					loff_t start, loff_t len)
389 {
390 	struct page *page;
391 
392 	if (!len)
393 		return;
394 
395 	page = get_new_data_page(inode, index, false);
396 
397 	if (!IS_ERR(page)) {
398 		wait_on_page_writeback(page);
399 		zero_user(page, start, len);
400 		set_page_dirty(page);
401 		f2fs_put_page(page, 1);
402 	}
403 }
404 
405 int truncate_hole(struct inode *inode, pgoff_t pg_start, pgoff_t pg_end)
406 {
407 	pgoff_t index;
408 	int err;
409 
410 	for (index = pg_start; index < pg_end; index++) {
411 		struct dnode_of_data dn;
412 		struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
413 
414 		f2fs_balance_fs(sbi);
415 
416 		mutex_lock_op(sbi, DATA_TRUNC);
417 		set_new_dnode(&dn, inode, NULL, NULL, 0);
418 		err = get_dnode_of_data(&dn, index, RDONLY_NODE);
419 		if (err) {
420 			mutex_unlock_op(sbi, DATA_TRUNC);
421 			if (err == -ENOENT)
422 				continue;
423 			return err;
424 		}
425 
426 		if (dn.data_blkaddr != NULL_ADDR)
427 			truncate_data_blocks_range(&dn, 1);
428 		f2fs_put_dnode(&dn);
429 		mutex_unlock_op(sbi, DATA_TRUNC);
430 	}
431 	return 0;
432 }
433 
434 static int punch_hole(struct inode *inode, loff_t offset, loff_t len, int mode)
435 {
436 	pgoff_t pg_start, pg_end;
437 	loff_t off_start, off_end;
438 	int ret = 0;
439 
440 	pg_start = ((unsigned long long) offset) >> PAGE_CACHE_SHIFT;
441 	pg_end = ((unsigned long long) offset + len) >> PAGE_CACHE_SHIFT;
442 
443 	off_start = offset & (PAGE_CACHE_SIZE - 1);
444 	off_end = (offset + len) & (PAGE_CACHE_SIZE - 1);
445 
446 	if (pg_start == pg_end) {
447 		fill_zero(inode, pg_start, off_start,
448 						off_end - off_start);
449 	} else {
450 		if (off_start)
451 			fill_zero(inode, pg_start++, off_start,
452 					PAGE_CACHE_SIZE - off_start);
453 		if (off_end)
454 			fill_zero(inode, pg_end, 0, off_end);
455 
456 		if (pg_start < pg_end) {
457 			struct address_space *mapping = inode->i_mapping;
458 			loff_t blk_start, blk_end;
459 
460 			blk_start = pg_start << PAGE_CACHE_SHIFT;
461 			blk_end = pg_end << PAGE_CACHE_SHIFT;
462 			truncate_inode_pages_range(mapping, blk_start,
463 					blk_end - 1);
464 			ret = truncate_hole(inode, pg_start, pg_end);
465 		}
466 	}
467 
468 	if (!(mode & FALLOC_FL_KEEP_SIZE) &&
469 		i_size_read(inode) <= (offset + len)) {
470 		i_size_write(inode, offset);
471 		mark_inode_dirty(inode);
472 	}
473 
474 	return ret;
475 }
476 
477 static int expand_inode_data(struct inode *inode, loff_t offset,
478 					loff_t len, int mode)
479 {
480 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
481 	pgoff_t index, pg_start, pg_end;
482 	loff_t new_size = i_size_read(inode);
483 	loff_t off_start, off_end;
484 	int ret = 0;
485 
486 	ret = inode_newsize_ok(inode, (len + offset));
487 	if (ret)
488 		return ret;
489 
490 	pg_start = ((unsigned long long) offset) >> PAGE_CACHE_SHIFT;
491 	pg_end = ((unsigned long long) offset + len) >> PAGE_CACHE_SHIFT;
492 
493 	off_start = offset & (PAGE_CACHE_SIZE - 1);
494 	off_end = (offset + len) & (PAGE_CACHE_SIZE - 1);
495 
496 	for (index = pg_start; index <= pg_end; index++) {
497 		struct dnode_of_data dn;
498 
499 		mutex_lock_op(sbi, DATA_NEW);
500 
501 		set_new_dnode(&dn, inode, NULL, NULL, 0);
502 		ret = get_dnode_of_data(&dn, index, 0);
503 		if (ret) {
504 			mutex_unlock_op(sbi, DATA_NEW);
505 			break;
506 		}
507 
508 		if (dn.data_blkaddr == NULL_ADDR) {
509 			ret = reserve_new_block(&dn);
510 			if (ret) {
511 				f2fs_put_dnode(&dn);
512 				mutex_unlock_op(sbi, DATA_NEW);
513 				break;
514 			}
515 		}
516 		f2fs_put_dnode(&dn);
517 
518 		mutex_unlock_op(sbi, DATA_NEW);
519 
520 		if (pg_start == pg_end)
521 			new_size = offset + len;
522 		else if (index == pg_start && off_start)
523 			new_size = (index + 1) << PAGE_CACHE_SHIFT;
524 		else if (index == pg_end)
525 			new_size = (index << PAGE_CACHE_SHIFT) + off_end;
526 		else
527 			new_size += PAGE_CACHE_SIZE;
528 	}
529 
530 	if (!(mode & FALLOC_FL_KEEP_SIZE) &&
531 		i_size_read(inode) < new_size) {
532 		i_size_write(inode, new_size);
533 		mark_inode_dirty(inode);
534 	}
535 
536 	return ret;
537 }
538 
539 static long f2fs_fallocate(struct file *file, int mode,
540 				loff_t offset, loff_t len)
541 {
542 	struct inode *inode = file->f_path.dentry->d_inode;
543 	long ret;
544 
545 	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
546 		return -EOPNOTSUPP;
547 
548 	if (mode & FALLOC_FL_PUNCH_HOLE)
549 		ret = punch_hole(inode, offset, len, mode);
550 	else
551 		ret = expand_inode_data(inode, offset, len, mode);
552 
553 	if (!ret) {
554 		inode->i_mtime = inode->i_ctime = CURRENT_TIME;
555 		mark_inode_dirty(inode);
556 	}
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 = filp->f_dentry->d_inode;
576 	struct f2fs_inode_info *fi = F2FS_I(inode);
577 	unsigned int flags;
578 	int ret;
579 
580 	switch (cmd) {
581 	case FS_IOC_GETFLAGS:
582 		flags = fi->i_flags & FS_FL_USER_VISIBLE;
583 		return put_user(flags, (int __user *) arg);
584 	case FS_IOC_SETFLAGS:
585 	{
586 		unsigned int oldflags;
587 
588 		ret = mnt_want_write(filp->f_path.mnt);
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(filp->f_path.mnt);
626 		return ret;
627 	}
628 	default:
629 		return -ENOTTY;
630 	}
631 }
632 
633 const struct file_operations f2fs_file_operations = {
634 	.llseek		= generic_file_llseek,
635 	.read		= do_sync_read,
636 	.write		= do_sync_write,
637 	.aio_read	= generic_file_aio_read,
638 	.aio_write	= generic_file_aio_write,
639 	.open		= generic_file_open,
640 	.mmap		= f2fs_file_mmap,
641 	.fsync		= f2fs_sync_file,
642 	.fallocate	= f2fs_fallocate,
643 	.unlocked_ioctl	= f2fs_ioctl,
644 	.splice_read	= generic_file_splice_read,
645 	.splice_write	= generic_file_splice_write,
646 };
647