xref: /openbmc/u-boot/fs/ext4/ext4_write.c (revision e9c847c3)
1 /*
2  * (C) Copyright 2011 - 2012 Samsung Electronics
3  * EXT4 filesystem implementation in Uboot by
4  * Uma Shankar <uma.shankar@samsung.com>
5  * Manjunatha C Achar <a.manjunatha@samsung.com>
6  *
7  * ext4ls and ext4load : Based on ext2 ls and load support in Uboot.
8  *		       Ext4 read optimization taken from Open-Moko
9  *		       Qi bootloader
10  *
11  * (C) Copyright 2004
12  * esd gmbh <www.esd-electronics.com>
13  * Reinhard Arlt <reinhard.arlt@esd-electronics.com>
14  *
15  * based on code from grub2 fs/ext2.c and fs/fshelp.c by
16  * GRUB  --  GRand Unified Bootloader
17  * Copyright (C) 2003, 2004  Free Software Foundation, Inc.
18  *
19  * ext4write : Based on generic ext4 protocol.
20  *
21  * SPDX-License-Identifier:	GPL-2.0+
22  */
23 
24 
25 #include <common.h>
26 #include <memalign.h>
27 #include <linux/stat.h>
28 #include <div64.h>
29 #include "ext4_common.h"
30 
31 static inline void ext4fs_sb_free_inodes_inc(struct ext2_sblock *sb)
32 {
33 	sb->free_inodes = cpu_to_le32(le32_to_cpu(sb->free_inodes) + 1);
34 }
35 
36 static inline void ext4fs_sb_free_blocks_inc(struct ext2_sblock *sb)
37 {
38 	sb->free_blocks = cpu_to_le32(le32_to_cpu(sb->free_blocks) + 1);
39 }
40 
41 static inline void ext4fs_bg_free_inodes_inc
42 	(struct ext2_block_group *bg, const struct ext_filesystem *fs)
43 {
44 	uint32_t free_inodes = le16_to_cpu(bg->free_inodes);
45 	if (fs->gdsize == 64)
46 		free_inodes += le16_to_cpu(bg->free_inodes_high) << 16;
47 	free_inodes++;
48 
49 	bg->free_inodes = cpu_to_le16(free_inodes & 0xffff);
50 	if (fs->gdsize == 64)
51 		bg->free_inodes_high = cpu_to_le16(free_inodes >> 16);
52 }
53 
54 static inline void ext4fs_bg_free_blocks_inc
55 	(struct ext2_block_group *bg, const struct ext_filesystem *fs)
56 {
57 	uint32_t free_blocks = le16_to_cpu(bg->free_blocks);
58 	if (fs->gdsize == 64)
59 		free_blocks += le16_to_cpu(bg->free_blocks_high) << 16;
60 	free_blocks++;
61 
62 	bg->free_blocks = cpu_to_le16(free_blocks & 0xffff);
63 	if (fs->gdsize == 64)
64 		bg->free_blocks_high = cpu_to_le16(free_blocks >> 16);
65 }
66 
67 static void ext4fs_update(void)
68 {
69 	short i;
70 	ext4fs_update_journal();
71 	struct ext_filesystem *fs = get_fs();
72 	struct ext2_block_group *bgd = NULL;
73 
74 	/* update  super block */
75 	put_ext4((uint64_t)(SUPERBLOCK_SIZE),
76 		 (struct ext2_sblock *)fs->sb, (uint32_t)SUPERBLOCK_SIZE);
77 
78 	/* update block bitmaps */
79 	for (i = 0; i < fs->no_blkgrp; i++) {
80 		bgd = ext4fs_get_group_descriptor(fs, i);
81 		bgd->bg_checksum = cpu_to_le16(ext4fs_checksum_update(i));
82 		uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
83 		put_ext4(b_bitmap_blk * fs->blksz,
84 			 fs->blk_bmaps[i], fs->blksz);
85 	}
86 
87 	/* update inode bitmaps */
88 	for (i = 0; i < fs->no_blkgrp; i++) {
89 		bgd = ext4fs_get_group_descriptor(fs, i);
90 		uint64_t i_bitmap_blk = ext4fs_bg_get_inode_id(bgd, fs);
91 		put_ext4(i_bitmap_blk * fs->blksz,
92 			 fs->inode_bmaps[i], fs->blksz);
93 	}
94 
95 	/* update the block group descriptor table */
96 	put_ext4((uint64_t)((uint64_t)fs->gdtable_blkno * (uint64_t)fs->blksz),
97 		 (struct ext2_block_group *)fs->gdtable,
98 		 (fs->blksz * fs->no_blk_pergdt));
99 
100 	ext4fs_dump_metadata();
101 
102 	gindex = 0;
103 	gd_index = 0;
104 }
105 
106 int ext4fs_get_bgdtable(void)
107 {
108 	int status;
109 	struct ext_filesystem *fs = get_fs();
110 	int gdsize_total = ROUND(fs->no_blkgrp * fs->gdsize, fs->blksz);
111 	fs->no_blk_pergdt = gdsize_total / fs->blksz;
112 
113 	/* allocate memory for gdtable */
114 	fs->gdtable = zalloc(gdsize_total);
115 	if (!fs->gdtable)
116 		return -ENOMEM;
117 	/* read the group descriptor table */
118 	status = ext4fs_devread((lbaint_t)fs->gdtable_blkno * fs->sect_perblk,
119 				0, fs->blksz * fs->no_blk_pergdt, fs->gdtable);
120 	if (status == 0)
121 		goto fail;
122 
123 	if (ext4fs_log_gdt(fs->gdtable)) {
124 		printf("Error in ext4fs_log_gdt\n");
125 		return -1;
126 	}
127 
128 	return 0;
129 fail:
130 	free(fs->gdtable);
131 	fs->gdtable = NULL;
132 
133 	return -1;
134 }
135 
136 static void delete_single_indirect_block(struct ext2_inode *inode)
137 {
138 	struct ext2_block_group *bgd = NULL;
139 	static int prev_bg_bmap_idx = -1;
140 	uint32_t blknr;
141 	int remainder;
142 	int bg_idx;
143 	int status;
144 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
145 	struct ext_filesystem *fs = get_fs();
146 	char *journal_buffer = zalloc(fs->blksz);
147 	if (!journal_buffer) {
148 		printf("No memory\n");
149 		return;
150 	}
151 
152 	/* deleting the single indirect block associated with inode */
153 	if (inode->b.blocks.indir_block != 0) {
154 		blknr = le32_to_cpu(inode->b.blocks.indir_block);
155 		debug("SIPB releasing %u\n", blknr);
156 		bg_idx = blknr / blk_per_grp;
157 		if (fs->blksz == 1024) {
158 			remainder = blknr % blk_per_grp;
159 			if (!remainder)
160 				bg_idx--;
161 		}
162 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
163 		/* get  block group descriptor table */
164 		bgd = ext4fs_get_group_descriptor(fs, bg_idx);
165 		ext4fs_bg_free_blocks_inc(bgd, fs);
166 		ext4fs_sb_free_blocks_inc(fs->sb);
167 		/* journal backup */
168 		if (prev_bg_bmap_idx != bg_idx) {
169 			uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
170 			status = ext4fs_devread(
171 					   b_bitmap_blk * fs->sect_perblk,
172 					   0, fs->blksz, journal_buffer);
173 			if (status == 0)
174 				goto fail;
175 			if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
176 				goto fail;
177 			prev_bg_bmap_idx = bg_idx;
178 		}
179 	}
180 fail:
181 	free(journal_buffer);
182 }
183 
184 static void delete_double_indirect_block(struct ext2_inode *inode)
185 {
186 	int i;
187 	short status;
188 	static int prev_bg_bmap_idx = -1;
189 	uint32_t blknr;
190 	int remainder;
191 	int bg_idx;
192 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
193 	__le32 *di_buffer = NULL;
194 	void *dib_start_addr = NULL;
195 	struct ext2_block_group *bgd = NULL;
196 	struct ext_filesystem *fs = get_fs();
197 	char *journal_buffer = zalloc(fs->blksz);
198 	if (!journal_buffer) {
199 		printf("No memory\n");
200 		return;
201 	}
202 
203 	if (inode->b.blocks.double_indir_block != 0) {
204 		di_buffer = zalloc(fs->blksz);
205 		if (!di_buffer) {
206 			printf("No memory\n");
207 			return;
208 		}
209 		dib_start_addr = di_buffer;
210 		blknr = le32_to_cpu(inode->b.blocks.double_indir_block);
211 		status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
212 					fs->blksz, (char *)di_buffer);
213 		for (i = 0; i < fs->blksz / sizeof(int); i++) {
214 			if (*di_buffer == 0)
215 				break;
216 
217 			debug("DICB releasing %u\n", *di_buffer);
218 			bg_idx = le32_to_cpu(*di_buffer) / blk_per_grp;
219 			if (fs->blksz == 1024) {
220 				remainder = le32_to_cpu(*di_buffer) % blk_per_grp;
221 				if (!remainder)
222 					bg_idx--;
223 			}
224 			/* get  block group descriptor table */
225 			bgd = ext4fs_get_group_descriptor(fs, bg_idx);
226 			ext4fs_reset_block_bmap(le32_to_cpu(*di_buffer),
227 					fs->blk_bmaps[bg_idx], bg_idx);
228 			di_buffer++;
229 			ext4fs_bg_free_blocks_inc(bgd, fs);
230 			ext4fs_sb_free_blocks_inc(fs->sb);
231 			/* journal backup */
232 			if (prev_bg_bmap_idx != bg_idx) {
233 				uint64_t b_bitmap_blk =
234 					ext4fs_bg_get_block_id(bgd, fs);
235 				status = ext4fs_devread(b_bitmap_blk
236 							* fs->sect_perblk, 0,
237 							fs->blksz,
238 							journal_buffer);
239 				if (status == 0)
240 					goto fail;
241 
242 				if (ext4fs_log_journal(journal_buffer,
243 						       b_bitmap_blk))
244 					goto fail;
245 				prev_bg_bmap_idx = bg_idx;
246 			}
247 		}
248 
249 		/* removing the parent double indirect block */
250 		blknr = le32_to_cpu(inode->b.blocks.double_indir_block);
251 		bg_idx = blknr / blk_per_grp;
252 		if (fs->blksz == 1024) {
253 			remainder = blknr % blk_per_grp;
254 			if (!remainder)
255 				bg_idx--;
256 		}
257 		/* get  block group descriptor table */
258 		bgd = ext4fs_get_group_descriptor(fs, bg_idx);
259 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
260 		ext4fs_bg_free_blocks_inc(bgd, fs);
261 		ext4fs_sb_free_blocks_inc(fs->sb);
262 		/* journal backup */
263 		if (prev_bg_bmap_idx != bg_idx) {
264 			uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
265 			status = ext4fs_devread(b_bitmap_blk * fs->sect_perblk,
266 						0, fs->blksz, journal_buffer);
267 			if (status == 0)
268 				goto fail;
269 
270 			if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
271 				goto fail;
272 			prev_bg_bmap_idx = bg_idx;
273 		}
274 		debug("DIPB releasing %d\n", blknr);
275 	}
276 fail:
277 	free(dib_start_addr);
278 	free(journal_buffer);
279 }
280 
281 static void delete_triple_indirect_block(struct ext2_inode *inode)
282 {
283 	int i, j;
284 	short status;
285 	static int prev_bg_bmap_idx = -1;
286 	uint32_t blknr;
287 	int remainder;
288 	int bg_idx;
289 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
290 	__le32 *tigp_buffer = NULL;
291 	void *tib_start_addr = NULL;
292 	__le32 *tip_buffer = NULL;
293 	void *tipb_start_addr = NULL;
294 	struct ext2_block_group *bgd = NULL;
295 	struct ext_filesystem *fs = get_fs();
296 	char *journal_buffer = zalloc(fs->blksz);
297 	if (!journal_buffer) {
298 		printf("No memory\n");
299 		return;
300 	}
301 
302 	if (inode->b.blocks.triple_indir_block != 0) {
303 		tigp_buffer = zalloc(fs->blksz);
304 		if (!tigp_buffer) {
305 			printf("No memory\n");
306 			return;
307 		}
308 		tib_start_addr = tigp_buffer;
309 		blknr = le32_to_cpu(inode->b.blocks.triple_indir_block);
310 		status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
311 					fs->blksz, (char *)tigp_buffer);
312 		for (i = 0; i < fs->blksz / sizeof(int); i++) {
313 			if (*tigp_buffer == 0)
314 				break;
315 			debug("tigp buffer releasing %u\n", *tigp_buffer);
316 
317 			tip_buffer = zalloc(fs->blksz);
318 			if (!tip_buffer)
319 				goto fail;
320 			tipb_start_addr = tip_buffer;
321 			status = ext4fs_devread((lbaint_t)le32_to_cpu(*tigp_buffer) *
322 						fs->sect_perblk, 0, fs->blksz,
323 						(char *)tip_buffer);
324 			for (j = 0; j < fs->blksz / sizeof(int); j++) {
325 				if (le32_to_cpu(*tip_buffer) == 0)
326 					break;
327 				bg_idx = le32_to_cpu(*tip_buffer) / blk_per_grp;
328 				if (fs->blksz == 1024) {
329 					remainder = le32_to_cpu(*tip_buffer) % blk_per_grp;
330 					if (!remainder)
331 						bg_idx--;
332 				}
333 
334 				ext4fs_reset_block_bmap(le32_to_cpu(*tip_buffer),
335 							fs->blk_bmaps[bg_idx],
336 							bg_idx);
337 
338 				tip_buffer++;
339 				/* get  block group descriptor table */
340 				bgd = ext4fs_get_group_descriptor(fs, bg_idx);
341 				ext4fs_bg_free_blocks_inc(bgd, fs);
342 				ext4fs_sb_free_blocks_inc(fs->sb);
343 				/* journal backup */
344 				if (prev_bg_bmap_idx != bg_idx) {
345 					uint64_t b_bitmap_blk =
346 						ext4fs_bg_get_block_id(bgd, fs);
347 					status =
348 					    ext4fs_devread(
349 							b_bitmap_blk *
350 							fs->sect_perblk, 0,
351 							fs->blksz,
352 							journal_buffer);
353 					if (status == 0)
354 						goto fail;
355 
356 					if (ext4fs_log_journal(journal_buffer,
357 							       b_bitmap_blk))
358 						goto fail;
359 					prev_bg_bmap_idx = bg_idx;
360 				}
361 			}
362 			free(tipb_start_addr);
363 			tipb_start_addr = NULL;
364 
365 			/*
366 			 * removing the grand parent blocks
367 			 * which is connected to inode
368 			 */
369 			bg_idx = le32_to_cpu(*tigp_buffer) / blk_per_grp;
370 			if (fs->blksz == 1024) {
371 				remainder = le32_to_cpu(*tigp_buffer) % blk_per_grp;
372 				if (!remainder)
373 					bg_idx--;
374 			}
375 			ext4fs_reset_block_bmap(le32_to_cpu(*tigp_buffer),
376 						fs->blk_bmaps[bg_idx], bg_idx);
377 
378 			tigp_buffer++;
379 			/* get  block group descriptor table */
380 			bgd = ext4fs_get_group_descriptor(fs, bg_idx);
381 			ext4fs_bg_free_blocks_inc(bgd, fs);
382 			ext4fs_sb_free_blocks_inc(fs->sb);
383 			/* journal backup */
384 			if (prev_bg_bmap_idx != bg_idx) {
385 				uint64_t b_bitmap_blk =
386 					ext4fs_bg_get_block_id(bgd, fs);
387 				memset(journal_buffer, '\0', fs->blksz);
388 				status = ext4fs_devread(b_bitmap_blk *
389 							fs->sect_perblk, 0,
390 							fs->blksz,
391 							journal_buffer);
392 				if (status == 0)
393 					goto fail;
394 
395 				if (ext4fs_log_journal(journal_buffer,
396 						       b_bitmap_blk))
397 					goto fail;
398 				prev_bg_bmap_idx = bg_idx;
399 			}
400 		}
401 
402 		/* removing the grand parent triple indirect block */
403 		blknr = le32_to_cpu(inode->b.blocks.triple_indir_block);
404 		bg_idx = blknr / blk_per_grp;
405 		if (fs->blksz == 1024) {
406 			remainder = blknr % blk_per_grp;
407 			if (!remainder)
408 				bg_idx--;
409 		}
410 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
411 		/* get  block group descriptor table */
412 		bgd = ext4fs_get_group_descriptor(fs, bg_idx);
413 		ext4fs_bg_free_blocks_inc(bgd, fs);
414 		ext4fs_sb_free_blocks_inc(fs->sb);
415 		/* journal backup */
416 		if (prev_bg_bmap_idx != bg_idx) {
417 			uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
418 			status = ext4fs_devread(b_bitmap_blk * fs->sect_perblk,
419 						0, fs->blksz, journal_buffer);
420 			if (status == 0)
421 				goto fail;
422 
423 			if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
424 				goto fail;
425 			prev_bg_bmap_idx = bg_idx;
426 		}
427 		debug("tigp buffer itself releasing %d\n", blknr);
428 	}
429 fail:
430 	free(tib_start_addr);
431 	free(tipb_start_addr);
432 	free(journal_buffer);
433 }
434 
435 static int ext4fs_delete_file(int inodeno)
436 {
437 	struct ext2_inode inode;
438 	short status;
439 	int i;
440 	int remainder;
441 	long int blknr;
442 	int bg_idx;
443 	int ibmap_idx;
444 	char *read_buffer = NULL;
445 	char *start_block_address = NULL;
446 	uint32_t no_blocks;
447 
448 	static int prev_bg_bmap_idx = -1;
449 	unsigned int inodes_per_block;
450 	uint32_t blkno;
451 	unsigned int blkoff;
452 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
453 	uint32_t inode_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
454 	struct ext2_inode *inode_buffer = NULL;
455 	struct ext2_block_group *bgd = NULL;
456 	struct ext_filesystem *fs = get_fs();
457 	char *journal_buffer = zalloc(fs->blksz);
458 	if (!journal_buffer)
459 		return -ENOMEM;
460 	status = ext4fs_read_inode(ext4fs_root, inodeno, &inode);
461 	if (status == 0)
462 		goto fail;
463 
464 	/* read the block no allocated to a file */
465 	no_blocks = le32_to_cpu(inode.size) / fs->blksz;
466 	if (le32_to_cpu(inode.size) % fs->blksz)
467 		no_blocks++;
468 
469 	if (le32_to_cpu(inode.flags) & EXT4_EXTENTS_FL) {
470 		/* FIXME delete extent index blocks, i.e. eh_depth >= 1 */
471 		struct ext4_extent_header *eh =
472 			(struct ext4_extent_header *)
473 				inode.b.blocks.dir_blocks;
474 		debug("del: dep=%d entries=%d\n", eh->eh_depth, eh->eh_entries);
475 	} else {
476 		delete_single_indirect_block(&inode);
477 		delete_double_indirect_block(&inode);
478 		delete_triple_indirect_block(&inode);
479 	}
480 
481 	/* release data blocks */
482 	for (i = 0; i < no_blocks; i++) {
483 		blknr = read_allocated_block(&inode, i);
484 		if (blknr == 0)
485 			continue;
486 		if (blknr < 0)
487 			goto fail;
488 		bg_idx = blknr / blk_per_grp;
489 		if (fs->blksz == 1024) {
490 			remainder = blknr % blk_per_grp;
491 			if (!remainder)
492 				bg_idx--;
493 		}
494 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx],
495 					bg_idx);
496 		debug("EXT4 Block releasing %ld: %d\n", blknr, bg_idx);
497 
498 		/* get  block group descriptor table */
499 		bgd = ext4fs_get_group_descriptor(fs, bg_idx);
500 		ext4fs_bg_free_blocks_inc(bgd, fs);
501 		ext4fs_sb_free_blocks_inc(fs->sb);
502 		/* journal backup */
503 		if (prev_bg_bmap_idx != bg_idx) {
504 			uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
505 			status = ext4fs_devread(b_bitmap_blk * fs->sect_perblk,
506 						0, fs->blksz,
507 						journal_buffer);
508 			if (status == 0)
509 				goto fail;
510 			if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
511 				goto fail;
512 			prev_bg_bmap_idx = bg_idx;
513 		}
514 	}
515 
516 	/* release inode */
517 	/* from the inode no to blockno */
518 	inodes_per_block = fs->blksz / fs->inodesz;
519 	ibmap_idx = inodeno / inode_per_grp;
520 
521 	/* get the block no */
522 	inodeno--;
523 	/* get  block group descriptor table */
524 	bgd = ext4fs_get_group_descriptor(fs, ibmap_idx);
525 	blkno = ext4fs_bg_get_inode_table_id(bgd, fs) +
526 		(inodeno % inode_per_grp) / inodes_per_block;
527 
528 	/* get the offset of the inode */
529 	blkoff = ((inodeno) % inodes_per_block) * fs->inodesz;
530 
531 	/* read the block no containing the inode */
532 	read_buffer = zalloc(fs->blksz);
533 	if (!read_buffer)
534 		goto fail;
535 	start_block_address = read_buffer;
536 	status = ext4fs_devread((lbaint_t)blkno * fs->sect_perblk,
537 				0, fs->blksz, read_buffer);
538 	if (status == 0)
539 		goto fail;
540 
541 	if (ext4fs_log_journal(read_buffer, blkno))
542 		goto fail;
543 
544 	read_buffer = read_buffer + blkoff;
545 	inode_buffer = (struct ext2_inode *)read_buffer;
546 	memset(inode_buffer, '\0', fs->inodesz);
547 
548 	/* write the inode to original position in inode table */
549 	if (ext4fs_put_metadata(start_block_address, blkno))
550 		goto fail;
551 
552 	/* update the respective inode bitmaps */
553 	inodeno++;
554 	ext4fs_reset_inode_bmap(inodeno, fs->inode_bmaps[ibmap_idx], ibmap_idx);
555 	ext4fs_bg_free_inodes_inc(bgd, fs);
556 	ext4fs_sb_free_inodes_inc(fs->sb);
557 	/* journal backup */
558 	memset(journal_buffer, '\0', fs->blksz);
559 	status = ext4fs_devread(ext4fs_bg_get_inode_id(bgd, fs) *
560 				fs->sect_perblk, 0, fs->blksz, journal_buffer);
561 	if (status == 0)
562 		goto fail;
563 	if (ext4fs_log_journal(journal_buffer, ext4fs_bg_get_inode_id(bgd, fs)))
564 		goto fail;
565 
566 	ext4fs_update();
567 	ext4fs_deinit();
568 	ext4fs_reinit_global();
569 
570 	if (ext4fs_init() != 0) {
571 		printf("error in File System init\n");
572 		goto fail;
573 	}
574 
575 	free(start_block_address);
576 	free(journal_buffer);
577 
578 	return 0;
579 fail:
580 	free(start_block_address);
581 	free(journal_buffer);
582 
583 	return -1;
584 }
585 
586 int ext4fs_init(void)
587 {
588 	short status;
589 	int i;
590 	uint32_t real_free_blocks = 0;
591 	struct ext_filesystem *fs = get_fs();
592 
593 	/* populate fs */
594 	fs->blksz = EXT2_BLOCK_SIZE(ext4fs_root);
595 	fs->sect_perblk = fs->blksz >> fs->dev_desc->log2blksz;
596 
597 	/* get the superblock */
598 	fs->sb = zalloc(SUPERBLOCK_SIZE);
599 	if (!fs->sb)
600 		return -ENOMEM;
601 	if (!ext4_read_superblock((char *)fs->sb))
602 		goto fail;
603 
604 	/* init journal */
605 	if (ext4fs_init_journal())
606 		goto fail;
607 
608 	/* get total no of blockgroups */
609 	fs->no_blkgrp = (uint32_t)ext4fs_div_roundup(
610 			le32_to_cpu(ext4fs_root->sblock.total_blocks)
611 			- le32_to_cpu(ext4fs_root->sblock.first_data_block),
612 			le32_to_cpu(ext4fs_root->sblock.blocks_per_group));
613 
614 	/* get the block group descriptor table */
615 	fs->gdtable_blkno = ((EXT2_MIN_BLOCK_SIZE == fs->blksz) + 1);
616 	if (ext4fs_get_bgdtable() == -1) {
617 		printf("Error in getting the block group descriptor table\n");
618 		goto fail;
619 	}
620 
621 	/* load all the available bitmap block of the partition */
622 	fs->blk_bmaps = zalloc(fs->no_blkgrp * sizeof(char *));
623 	if (!fs->blk_bmaps)
624 		goto fail;
625 	for (i = 0; i < fs->no_blkgrp; i++) {
626 		fs->blk_bmaps[i] = zalloc(fs->blksz);
627 		if (!fs->blk_bmaps[i])
628 			goto fail;
629 	}
630 
631 	for (i = 0; i < fs->no_blkgrp; i++) {
632 		struct ext2_block_group *bgd =
633 			ext4fs_get_group_descriptor(fs, i);
634 		status = ext4fs_devread(ext4fs_bg_get_block_id(bgd, fs) *
635 				   fs->sect_perblk, 0,
636 				   fs->blksz, (char *)fs->blk_bmaps[i]);
637 		if (status == 0)
638 			goto fail;
639 	}
640 
641 	/* load all the available inode bitmap of the partition */
642 	fs->inode_bmaps = zalloc(fs->no_blkgrp * sizeof(unsigned char *));
643 	if (!fs->inode_bmaps)
644 		goto fail;
645 	for (i = 0; i < fs->no_blkgrp; i++) {
646 		fs->inode_bmaps[i] = zalloc(fs->blksz);
647 		if (!fs->inode_bmaps[i])
648 			goto fail;
649 	}
650 
651 	for (i = 0; i < fs->no_blkgrp; i++) {
652 		struct ext2_block_group *bgd =
653 			ext4fs_get_group_descriptor(fs, i);
654 		status = ext4fs_devread(ext4fs_bg_get_inode_id(bgd, fs) *
655 					fs->sect_perblk,
656 					0, fs->blksz,
657 					(char *)fs->inode_bmaps[i]);
658 		if (status == 0)
659 			goto fail;
660 	}
661 
662 	/*
663 	 * check filesystem consistency with free blocks of file system
664 	 * some time we observed that superblock freeblocks does not match
665 	 * with the  blockgroups freeblocks when improper
666 	 * reboot of a linux kernel
667 	 */
668 	for (i = 0; i < fs->no_blkgrp; i++) {
669 		struct ext2_block_group *bgd =
670 			ext4fs_get_group_descriptor(fs, i);
671 		real_free_blocks = real_free_blocks +
672 			ext4fs_bg_get_free_blocks(bgd, fs);
673 	}
674 	if (real_free_blocks != ext4fs_sb_get_free_blocks(fs->sb))
675 		ext4fs_sb_set_free_blocks(fs->sb, real_free_blocks);
676 
677 	return 0;
678 fail:
679 	ext4fs_deinit();
680 
681 	return -1;
682 }
683 
684 void ext4fs_deinit(void)
685 {
686 	int i;
687 	struct ext2_inode inode_journal;
688 	struct journal_superblock_t *jsb;
689 	uint32_t blknr;
690 	struct ext_filesystem *fs = get_fs();
691 	uint32_t new_feature_incompat;
692 
693 	/* free journal */
694 	char *temp_buff = zalloc(fs->blksz);
695 	if (temp_buff) {
696 		ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO,
697 				  &inode_journal);
698 		blknr = read_allocated_block(&inode_journal,
699 					EXT2_JOURNAL_SUPERBLOCK);
700 		ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0, fs->blksz,
701 			       temp_buff);
702 		jsb = (struct journal_superblock_t *)temp_buff;
703 		jsb->s_start = 0;
704 		put_ext4((uint64_t) ((uint64_t)blknr * (uint64_t)fs->blksz),
705 			 (struct journal_superblock_t *)temp_buff, fs->blksz);
706 		free(temp_buff);
707 	}
708 	ext4fs_free_journal();
709 
710 	/* get the superblock */
711 	ext4_read_superblock((char *)fs->sb);
712 	new_feature_incompat = le32_to_cpu(fs->sb->feature_incompat);
713 	new_feature_incompat &= ~EXT3_FEATURE_INCOMPAT_RECOVER;
714 	fs->sb->feature_incompat = cpu_to_le32(new_feature_incompat);
715 	put_ext4((uint64_t)(SUPERBLOCK_SIZE),
716 		 (struct ext2_sblock *)fs->sb, (uint32_t)SUPERBLOCK_SIZE);
717 	free(fs->sb);
718 	fs->sb = NULL;
719 
720 	if (fs->blk_bmaps) {
721 		for (i = 0; i < fs->no_blkgrp; i++) {
722 			free(fs->blk_bmaps[i]);
723 			fs->blk_bmaps[i] = NULL;
724 		}
725 		free(fs->blk_bmaps);
726 		fs->blk_bmaps = NULL;
727 	}
728 
729 	if (fs->inode_bmaps) {
730 		for (i = 0; i < fs->no_blkgrp; i++) {
731 			free(fs->inode_bmaps[i]);
732 			fs->inode_bmaps[i] = NULL;
733 		}
734 		free(fs->inode_bmaps);
735 		fs->inode_bmaps = NULL;
736 	}
737 
738 
739 	free(fs->gdtable);
740 	fs->gdtable = NULL;
741 	/*
742 	 * reinitiliazed the global inode and
743 	 * block bitmap first execution check variables
744 	 */
745 	fs->first_pass_ibmap = 0;
746 	fs->first_pass_bbmap = 0;
747 	fs->curr_inode_no = 0;
748 	fs->curr_blkno = 0;
749 }
750 
751 /*
752  * Write data to filesystem blocks. Uses same optimization for
753  * contigous sectors as ext4fs_read_file
754  */
755 static int ext4fs_write_file(struct ext2_inode *file_inode,
756 			     int pos, unsigned int len, char *buf)
757 {
758 	int i;
759 	int blockcnt;
760 	uint32_t filesize = le32_to_cpu(file_inode->size);
761 	struct ext_filesystem *fs = get_fs();
762 	int log2blksz = fs->dev_desc->log2blksz;
763 	int log2_fs_blocksize = LOG2_BLOCK_SIZE(ext4fs_root) - log2blksz;
764 	int previous_block_number = -1;
765 	int delayed_start = 0;
766 	int delayed_extent = 0;
767 	int delayed_next = 0;
768 	char *delayed_buf = NULL;
769 
770 	/* Adjust len so it we can't read past the end of the file. */
771 	if (len > filesize)
772 		len = filesize;
773 
774 	blockcnt = ((len + pos) + fs->blksz - 1) / fs->blksz;
775 
776 	for (i = pos / fs->blksz; i < blockcnt; i++) {
777 		long int blknr;
778 		int blockend = fs->blksz;
779 		int skipfirst = 0;
780 		blknr = read_allocated_block(file_inode, i);
781 		if (blknr <= 0)
782 			return -1;
783 
784 		blknr = blknr << log2_fs_blocksize;
785 
786 		if (blknr) {
787 			if (previous_block_number != -1) {
788 				if (delayed_next == blknr) {
789 					delayed_extent += blockend;
790 					delayed_next += blockend >> log2blksz;
791 				} else {	/* spill */
792 					put_ext4((uint64_t)
793 						 ((uint64_t)delayed_start << log2blksz),
794 						 delayed_buf,
795 						 (uint32_t) delayed_extent);
796 					previous_block_number = blknr;
797 					delayed_start = blknr;
798 					delayed_extent = blockend;
799 					delayed_buf = buf;
800 					delayed_next = blknr +
801 					    (blockend >> log2blksz);
802 				}
803 			} else {
804 				previous_block_number = blknr;
805 				delayed_start = blknr;
806 				delayed_extent = blockend;
807 				delayed_buf = buf;
808 				delayed_next = blknr +
809 				    (blockend >> log2blksz);
810 			}
811 		} else {
812 			if (previous_block_number != -1) {
813 				/* spill */
814 				put_ext4((uint64_t) ((uint64_t)delayed_start <<
815 						     log2blksz),
816 					 delayed_buf,
817 					 (uint32_t) delayed_extent);
818 				previous_block_number = -1;
819 			}
820 			memset(buf, 0, fs->blksz - skipfirst);
821 		}
822 		buf += fs->blksz - skipfirst;
823 	}
824 	if (previous_block_number != -1) {
825 		/* spill */
826 		put_ext4((uint64_t) ((uint64_t)delayed_start << log2blksz),
827 			 delayed_buf, (uint32_t) delayed_extent);
828 		previous_block_number = -1;
829 	}
830 
831 	return len;
832 }
833 
834 int ext4fs_write(const char *fname, unsigned char *buffer,
835 					unsigned long sizebytes)
836 {
837 	int ret = 0;
838 	struct ext2_inode *file_inode = NULL;
839 	unsigned char *inode_buffer = NULL;
840 	int parent_inodeno;
841 	int inodeno;
842 	time_t timestamp = 0;
843 
844 	uint64_t bytes_reqd_for_file;
845 	unsigned int blks_reqd_for_file;
846 	unsigned int blocks_remaining;
847 	int existing_file_inodeno;
848 	char *temp_ptr = NULL;
849 	long int itable_blkno;
850 	long int parent_itable_blkno;
851 	long int blkoff;
852 	struct ext2_sblock *sblock = &(ext4fs_root->sblock);
853 	unsigned int inodes_per_block;
854 	unsigned int ibmap_idx;
855 	struct ext2_block_group *bgd = NULL;
856 	struct ext_filesystem *fs = get_fs();
857 	ALLOC_CACHE_ALIGN_BUFFER(char, filename, 256);
858 	memset(filename, 0x00, 256);
859 
860 	g_parent_inode = zalloc(fs->inodesz);
861 	if (!g_parent_inode)
862 		goto fail;
863 
864 	if (ext4fs_init() != 0) {
865 		printf("error in File System init\n");
866 		return -1;
867 	}
868 	inodes_per_block = fs->blksz / fs->inodesz;
869 	parent_inodeno = ext4fs_get_parent_inode_num(fname, filename, F_FILE);
870 	if (parent_inodeno == -1)
871 		goto fail;
872 	if (ext4fs_iget(parent_inodeno, g_parent_inode))
873 		goto fail;
874 	/* do not mess up a directory using hash trees */
875 	if (le32_to_cpu(g_parent_inode->flags) & EXT4_INDEX_FL) {
876 		printf("hash tree directory\n");
877 		goto fail;
878 	}
879 	/* check if the filename is already present in root */
880 	existing_file_inodeno = ext4fs_filename_unlink(filename);
881 	if (existing_file_inodeno != -1) {
882 		ret = ext4fs_delete_file(existing_file_inodeno);
883 		fs->first_pass_bbmap = 0;
884 		fs->curr_blkno = 0;
885 
886 		fs->first_pass_ibmap = 0;
887 		fs->curr_inode_no = 0;
888 		if (ret)
889 			goto fail;
890 	}
891 	/* calucalate how many blocks required */
892 	bytes_reqd_for_file = sizebytes;
893 	blks_reqd_for_file = lldiv(bytes_reqd_for_file, fs->blksz);
894 	if (do_div(bytes_reqd_for_file, fs->blksz) != 0) {
895 		blks_reqd_for_file++;
896 		debug("total bytes for a file %u\n", blks_reqd_for_file);
897 	}
898 	blocks_remaining = blks_reqd_for_file;
899 	/* test for available space in partition */
900 	if (le32_to_cpu(fs->sb->free_blocks) < blks_reqd_for_file) {
901 		printf("Not enough space on partition !!!\n");
902 		goto fail;
903 	}
904 
905 	inodeno = ext4fs_update_parent_dentry(filename, FILETYPE_REG);
906 	if (inodeno == -1)
907 		goto fail;
908 	/* prepare file inode */
909 	inode_buffer = zalloc(fs->inodesz);
910 	if (!inode_buffer)
911 		goto fail;
912 	file_inode = (struct ext2_inode *)inode_buffer;
913 	file_inode->mode = cpu_to_le16(S_IFREG | S_IRWXU |
914 	    S_IRGRP | S_IROTH | S_IXGRP | S_IXOTH);
915 	/* ToDo: Update correct time */
916 	file_inode->mtime = cpu_to_le32(timestamp);
917 	file_inode->atime = cpu_to_le32(timestamp);
918 	file_inode->ctime = cpu_to_le32(timestamp);
919 	file_inode->nlinks = cpu_to_le16(1);
920 	file_inode->size = cpu_to_le32(sizebytes);
921 
922 	/* Allocate data blocks */
923 	ext4fs_allocate_blocks(file_inode, blocks_remaining,
924 			       &blks_reqd_for_file);
925 	file_inode->blockcnt = cpu_to_le32((blks_reqd_for_file * fs->blksz) >>
926 		fs->dev_desc->log2blksz);
927 
928 	temp_ptr = zalloc(fs->blksz);
929 	if (!temp_ptr)
930 		goto fail;
931 	ibmap_idx = inodeno / le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
932 	inodeno--;
933 	bgd = ext4fs_get_group_descriptor(fs, ibmap_idx);
934 	itable_blkno = ext4fs_bg_get_inode_table_id(bgd, fs) +
935 			(inodeno % le32_to_cpu(sblock->inodes_per_group)) /
936 			inodes_per_block;
937 	blkoff = (inodeno % inodes_per_block) * fs->inodesz;
938 	ext4fs_devread((lbaint_t)itable_blkno * fs->sect_perblk, 0, fs->blksz,
939 		       temp_ptr);
940 	if (ext4fs_log_journal(temp_ptr, itable_blkno))
941 		goto fail;
942 
943 	memcpy(temp_ptr + blkoff, inode_buffer, fs->inodesz);
944 	if (ext4fs_put_metadata(temp_ptr, itable_blkno))
945 		goto fail;
946 	/* copy the file content into data blocks */
947 	if (ext4fs_write_file(file_inode, 0, sizebytes, (char *)buffer) == -1) {
948 		printf("Error in copying content\n");
949 		/* FIXME: Deallocate data blocks */
950 		goto fail;
951 	}
952 	ibmap_idx = parent_inodeno / le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
953 	parent_inodeno--;
954 	bgd = ext4fs_get_group_descriptor(fs, ibmap_idx);
955 	parent_itable_blkno = ext4fs_bg_get_inode_table_id(bgd, fs) +
956 	    (parent_inodeno %
957 	     le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
958 	blkoff = (parent_inodeno % inodes_per_block) * fs->inodesz;
959 	if (parent_itable_blkno != itable_blkno) {
960 		memset(temp_ptr, '\0', fs->blksz);
961 		ext4fs_devread((lbaint_t)parent_itable_blkno * fs->sect_perblk,
962 			       0, fs->blksz, temp_ptr);
963 		if (ext4fs_log_journal(temp_ptr, parent_itable_blkno))
964 			goto fail;
965 
966 		memcpy(temp_ptr + blkoff, g_parent_inode, fs->inodesz);
967 		if (ext4fs_put_metadata(temp_ptr, parent_itable_blkno))
968 			goto fail;
969 	} else {
970 		/*
971 		 * If parent and child fall in same inode table block
972 		 * both should be kept in 1 buffer
973 		 */
974 		memcpy(temp_ptr + blkoff, g_parent_inode, fs->inodesz);
975 		gd_index--;
976 		if (ext4fs_put_metadata(temp_ptr, itable_blkno))
977 			goto fail;
978 	}
979 	ext4fs_update();
980 	ext4fs_deinit();
981 
982 	fs->first_pass_bbmap = 0;
983 	fs->curr_blkno = 0;
984 	fs->first_pass_ibmap = 0;
985 	fs->curr_inode_no = 0;
986 	free(inode_buffer);
987 	free(g_parent_inode);
988 	free(temp_ptr);
989 	g_parent_inode = NULL;
990 
991 	return 0;
992 fail:
993 	ext4fs_deinit();
994 	free(inode_buffer);
995 	free(g_parent_inode);
996 	free(temp_ptr);
997 	g_parent_inode = NULL;
998 
999 	return -1;
1000 }
1001 
1002 int ext4_write_file(const char *filename, void *buf, loff_t offset,
1003 		    loff_t len, loff_t *actwrite)
1004 {
1005 	int ret;
1006 
1007 	if (offset != 0) {
1008 		printf("** Cannot support non-zero offset **\n");
1009 		return -1;
1010 	}
1011 
1012 	ret = ext4fs_write(filename, buf, len);
1013 	if (ret) {
1014 		printf("** Error ext4fs_write() **\n");
1015 		goto fail;
1016 	}
1017 
1018 	*actwrite = len;
1019 
1020 	return 0;
1021 
1022 fail:
1023 	*actwrite = 0;
1024 
1025 	return -1;
1026 }
1027