xref: /rk3399_rockchip-uboot/fs/ext4/ext4_write.c (revision de9e831675d72c08c2cc3361a8e9b413ff3facec)
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(struct ext2_block_group *bg)
42 {
43 	bg->free_inodes = cpu_to_le16(le16_to_cpu(bg->free_inodes) + 1);
44 }
45 
46 static inline void ext4fs_bg_free_blocks_inc(struct ext2_block_group *bg)
47 {
48 	bg->free_blocks = cpu_to_le16(le16_to_cpu(bg->free_blocks) + 1);
49 }
50 
51 static void ext4fs_update(void)
52 {
53 	short i;
54 	ext4fs_update_journal();
55 	struct ext_filesystem *fs = get_fs();
56 
57 	/* update  super block */
58 	put_ext4((uint64_t)(SUPERBLOCK_SIZE),
59 		 (struct ext2_sblock *)fs->sb, (uint32_t)SUPERBLOCK_SIZE);
60 
61 	/* update block groups */
62 	for (i = 0; i < fs->no_blkgrp; i++) {
63 		fs->bgd[i].bg_checksum = cpu_to_le16(ext4fs_checksum_update(i));
64 		put_ext4((uint64_t)le32_to_cpu(fs->bgd[i].block_id) * fs->blksz,
65 			 fs->blk_bmaps[i], fs->blksz);
66 	}
67 
68 	/* update inode table groups */
69 	for (i = 0; i < fs->no_blkgrp; i++) {
70 		put_ext4((uint64_t)le32_to_cpu(fs->bgd[i].inode_id) * fs->blksz,
71 			 fs->inode_bmaps[i], fs->blksz);
72 	}
73 
74 	/* update the block group descriptor table */
75 	put_ext4((uint64_t)((uint64_t)fs->gdtable_blkno * (uint64_t)fs->blksz),
76 		 (struct ext2_block_group *)fs->gdtable,
77 		 (fs->blksz * fs->no_blk_pergdt));
78 
79 	ext4fs_dump_metadata();
80 
81 	gindex = 0;
82 	gd_index = 0;
83 }
84 
85 int ext4fs_get_bgdtable(void)
86 {
87 	int status;
88 	int grp_desc_size;
89 	struct ext_filesystem *fs = get_fs();
90 	grp_desc_size = sizeof(struct ext2_block_group);
91 	fs->no_blk_pergdt = (fs->no_blkgrp * grp_desc_size) / fs->blksz;
92 	if ((fs->no_blkgrp * grp_desc_size) % fs->blksz)
93 		fs->no_blk_pergdt++;
94 
95 	/* allocate memory for gdtable */
96 	fs->gdtable = zalloc(fs->blksz * fs->no_blk_pergdt);
97 	if (!fs->gdtable)
98 		return -ENOMEM;
99 	/* read the group descriptor table */
100 	status = ext4fs_devread((lbaint_t)fs->gdtable_blkno * fs->sect_perblk,
101 				0, fs->blksz * fs->no_blk_pergdt, fs->gdtable);
102 	if (status == 0)
103 		goto fail;
104 
105 	if (ext4fs_log_gdt(fs->gdtable)) {
106 		printf("Error in ext4fs_log_gdt\n");
107 		return -1;
108 	}
109 
110 	return 0;
111 fail:
112 	free(fs->gdtable);
113 	fs->gdtable = NULL;
114 
115 	return -1;
116 }
117 
118 static void delete_single_indirect_block(struct ext2_inode *inode)
119 {
120 	struct ext2_block_group *bgd = NULL;
121 	static int prev_bg_bmap_idx = -1;
122 	uint32_t blknr;
123 	int remainder;
124 	int bg_idx;
125 	int status;
126 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
127 	struct ext_filesystem *fs = get_fs();
128 	char *journal_buffer = zalloc(fs->blksz);
129 	if (!journal_buffer) {
130 		printf("No memory\n");
131 		return;
132 	}
133 	/* get  block group descriptor table */
134 	bgd = (struct ext2_block_group *)fs->gdtable;
135 
136 	/* deleting the single indirect block associated with inode */
137 	if (inode->b.blocks.indir_block != 0) {
138 		blknr = le32_to_cpu(inode->b.blocks.indir_block);
139 		debug("SIPB releasing %u\n", blknr);
140 		bg_idx = blknr / blk_per_grp;
141 		if (fs->blksz == 1024) {
142 			remainder = blknr % blk_per_grp;
143 			if (!remainder)
144 				bg_idx--;
145 		}
146 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
147 		ext4fs_bg_free_blocks_inc(&bgd[bg_idx]);
148 		ext4fs_sb_free_blocks_inc(fs->sb);
149 		/* journal backup */
150 		if (prev_bg_bmap_idx != bg_idx) {
151 			status = ext4fs_devread(
152 					   (lbaint_t)le32_to_cpu(bgd[bg_idx].block_id) *
153 					   fs->sect_perblk, 0, fs->blksz,
154 					   journal_buffer);
155 			if (status == 0)
156 				goto fail;
157 			if (ext4fs_log_journal
158 			    (journal_buffer, le32_to_cpu(bgd[bg_idx].block_id)))
159 				goto fail;
160 			prev_bg_bmap_idx = bg_idx;
161 		}
162 	}
163 fail:
164 	free(journal_buffer);
165 }
166 
167 static void delete_double_indirect_block(struct ext2_inode *inode)
168 {
169 	int i;
170 	short status;
171 	static int prev_bg_bmap_idx = -1;
172 	uint32_t blknr;
173 	int remainder;
174 	int bg_idx;
175 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
176 	__le32 *di_buffer = NULL;
177 	void *dib_start_addr = NULL;
178 	struct ext2_block_group *bgd = NULL;
179 	struct ext_filesystem *fs = get_fs();
180 	char *journal_buffer = zalloc(fs->blksz);
181 	if (!journal_buffer) {
182 		printf("No memory\n");
183 		return;
184 	}
185 	/* get the block group descriptor table */
186 	bgd = (struct ext2_block_group *)fs->gdtable;
187 
188 	if (inode->b.blocks.double_indir_block != 0) {
189 		di_buffer = zalloc(fs->blksz);
190 		if (!di_buffer) {
191 			printf("No memory\n");
192 			return;
193 		}
194 		dib_start_addr = di_buffer;
195 		blknr = le32_to_cpu(inode->b.blocks.double_indir_block);
196 		status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
197 					fs->blksz, (char *)di_buffer);
198 		for (i = 0; i < fs->blksz / sizeof(int); i++) {
199 			if (*di_buffer == 0)
200 				break;
201 
202 			debug("DICB releasing %u\n", *di_buffer);
203 			bg_idx = le32_to_cpu(*di_buffer) / blk_per_grp;
204 			if (fs->blksz == 1024) {
205 				remainder = le32_to_cpu(*di_buffer) % blk_per_grp;
206 				if (!remainder)
207 					bg_idx--;
208 			}
209 			ext4fs_reset_block_bmap(le32_to_cpu(*di_buffer),
210 					fs->blk_bmaps[bg_idx], bg_idx);
211 			di_buffer++;
212 			ext4fs_bg_free_blocks_inc(&bgd[bg_idx]);
213 			ext4fs_sb_free_blocks_inc(fs->sb);
214 			/* journal backup */
215 			if (prev_bg_bmap_idx != bg_idx) {
216 				status = ext4fs_devread(
217 							(lbaint_t)le32_to_cpu(bgd[bg_idx].block_id)
218 							* fs->sect_perblk, 0,
219 							fs->blksz,
220 							journal_buffer);
221 				if (status == 0)
222 					goto fail;
223 
224 				if (ext4fs_log_journal(journal_buffer,
225 							le32_to_cpu(bgd[bg_idx].block_id)))
226 					goto fail;
227 				prev_bg_bmap_idx = bg_idx;
228 			}
229 		}
230 
231 		/* removing the parent double indirect block */
232 		blknr = le32_to_cpu(inode->b.blocks.double_indir_block);
233 		bg_idx = blknr / blk_per_grp;
234 		if (fs->blksz == 1024) {
235 			remainder = blknr % blk_per_grp;
236 			if (!remainder)
237 				bg_idx--;
238 		}
239 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
240 		ext4fs_bg_free_blocks_inc(&bgd[bg_idx]);
241 		ext4fs_sb_free_blocks_inc(fs->sb);
242 		/* journal backup */
243 		if (prev_bg_bmap_idx != bg_idx) {
244 			memset(journal_buffer, '\0', fs->blksz);
245 			status = ext4fs_devread((lbaint_t)le32_to_cpu(bgd[bg_idx].block_id) *
246 						fs->sect_perblk, 0, fs->blksz,
247 						journal_buffer);
248 			if (status == 0)
249 				goto fail;
250 
251 			if (ext4fs_log_journal(journal_buffer,
252 						le32_to_cpu(bgd[bg_idx].block_id)))
253 				goto fail;
254 			prev_bg_bmap_idx = bg_idx;
255 		}
256 		debug("DIPB releasing %d\n", blknr);
257 	}
258 fail:
259 	free(dib_start_addr);
260 	free(journal_buffer);
261 }
262 
263 static void delete_triple_indirect_block(struct ext2_inode *inode)
264 {
265 	int i, j;
266 	short status;
267 	static int prev_bg_bmap_idx = -1;
268 	uint32_t blknr;
269 	int remainder;
270 	int bg_idx;
271 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
272 	__le32 *tigp_buffer = NULL;
273 	void *tib_start_addr = NULL;
274 	__le32 *tip_buffer = NULL;
275 	void *tipb_start_addr = NULL;
276 	struct ext2_block_group *bgd = NULL;
277 	struct ext_filesystem *fs = get_fs();
278 	char *journal_buffer = zalloc(fs->blksz);
279 	if (!journal_buffer) {
280 		printf("No memory\n");
281 		return;
282 	}
283 	/* get block group descriptor table */
284 	bgd = (struct ext2_block_group *)fs->gdtable;
285 
286 	if (inode->b.blocks.triple_indir_block != 0) {
287 		tigp_buffer = zalloc(fs->blksz);
288 		if (!tigp_buffer) {
289 			printf("No memory\n");
290 			return;
291 		}
292 		tib_start_addr = tigp_buffer;
293 		blknr = le32_to_cpu(inode->b.blocks.triple_indir_block);
294 		status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
295 					fs->blksz, (char *)tigp_buffer);
296 		for (i = 0; i < fs->blksz / sizeof(int); i++) {
297 			if (*tigp_buffer == 0)
298 				break;
299 			debug("tigp buffer releasing %u\n", *tigp_buffer);
300 
301 			tip_buffer = zalloc(fs->blksz);
302 			if (!tip_buffer)
303 				goto fail;
304 			tipb_start_addr = tip_buffer;
305 			status = ext4fs_devread((lbaint_t)le32_to_cpu(*tigp_buffer) *
306 						fs->sect_perblk, 0, fs->blksz,
307 						(char *)tip_buffer);
308 			for (j = 0; j < fs->blksz / sizeof(int); j++) {
309 				if (le32_to_cpu(*tip_buffer) == 0)
310 					break;
311 				bg_idx = le32_to_cpu(*tip_buffer) / blk_per_grp;
312 				if (fs->blksz == 1024) {
313 					remainder = le32_to_cpu(*tip_buffer) % blk_per_grp;
314 					if (!remainder)
315 						bg_idx--;
316 				}
317 
318 				ext4fs_reset_block_bmap(le32_to_cpu(*tip_buffer),
319 							fs->blk_bmaps[bg_idx],
320 							bg_idx);
321 
322 				tip_buffer++;
323 				ext4fs_bg_free_blocks_inc(&bgd[bg_idx]);
324 				ext4fs_sb_free_blocks_inc(fs->sb);
325 				/* journal backup */
326 				if (prev_bg_bmap_idx != bg_idx) {
327 					status =
328 					    ext4fs_devread(
329 							(lbaint_t)le32_to_cpu(bgd[bg_idx].block_id) *
330 							fs->sect_perblk, 0,
331 							fs->blksz,
332 							journal_buffer);
333 					if (status == 0)
334 						goto fail;
335 
336 					if (ext4fs_log_journal(journal_buffer,
337 							       le32_to_cpu(bgd[bg_idx].block_id)))
338 						goto fail;
339 					prev_bg_bmap_idx = bg_idx;
340 				}
341 			}
342 			free(tipb_start_addr);
343 			tipb_start_addr = NULL;
344 
345 			/*
346 			 * removing the grand parent blocks
347 			 * which is connected to inode
348 			 */
349 			bg_idx = le32_to_cpu(*tigp_buffer) / blk_per_grp;
350 			if (fs->blksz == 1024) {
351 				remainder = le32_to_cpu(*tigp_buffer) % blk_per_grp;
352 				if (!remainder)
353 					bg_idx--;
354 			}
355 			ext4fs_reset_block_bmap(le32_to_cpu(*tigp_buffer),
356 						fs->blk_bmaps[bg_idx], bg_idx);
357 
358 			tigp_buffer++;
359 			ext4fs_bg_free_blocks_inc(&bgd[bg_idx]);
360 			ext4fs_sb_free_blocks_inc(fs->sb);
361 			/* journal backup */
362 			if (prev_bg_bmap_idx != bg_idx) {
363 				memset(journal_buffer, '\0', fs->blksz);
364 				status =
365 				    ext4fs_devread(
366 						   (lbaint_t)le32_to_cpu(bgd[bg_idx].block_id) *
367 						   fs->sect_perblk, 0,
368 						   fs->blksz, journal_buffer);
369 				if (status == 0)
370 					goto fail;
371 
372 				if (ext4fs_log_journal(journal_buffer,
373 							le32_to_cpu(bgd[bg_idx].block_id)))
374 					goto fail;
375 				prev_bg_bmap_idx = bg_idx;
376 			}
377 		}
378 
379 		/* removing the grand parent triple indirect block */
380 		blknr = le32_to_cpu(inode->b.blocks.triple_indir_block);
381 		bg_idx = blknr / blk_per_grp;
382 		if (fs->blksz == 1024) {
383 			remainder = blknr % blk_per_grp;
384 			if (!remainder)
385 				bg_idx--;
386 		}
387 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
388 		ext4fs_bg_free_blocks_inc(&bgd[bg_idx]);
389 		ext4fs_sb_free_blocks_inc(fs->sb);
390 		/* journal backup */
391 		if (prev_bg_bmap_idx != bg_idx) {
392 			memset(journal_buffer, '\0', fs->blksz);
393 			status = ext4fs_devread(
394 						(lbaint_t)le32_to_cpu(bgd[bg_idx].block_id) *
395 						fs->sect_perblk, 0, fs->blksz,
396 						journal_buffer);
397 			if (status == 0)
398 				goto fail;
399 
400 			if (ext4fs_log_journal(journal_buffer,
401 						le32_to_cpu(bgd[bg_idx].block_id)))
402 				goto fail;
403 			prev_bg_bmap_idx = bg_idx;
404 		}
405 		debug("tigp buffer itself releasing %d\n", blknr);
406 	}
407 fail:
408 	free(tib_start_addr);
409 	free(tipb_start_addr);
410 	free(journal_buffer);
411 }
412 
413 static int ext4fs_delete_file(int inodeno)
414 {
415 	struct ext2_inode inode;
416 	short status;
417 	int i;
418 	int remainder;
419 	long int blknr;
420 	int bg_idx;
421 	int ibmap_idx;
422 	char *read_buffer = NULL;
423 	char *start_block_address = NULL;
424 	uint32_t no_blocks;
425 
426 	static int prev_bg_bmap_idx = -1;
427 	unsigned int inodes_per_block;
428 	uint32_t blkno;
429 	unsigned int blkoff;
430 	uint32_t blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
431 	uint32_t inode_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
432 	struct ext2_inode *inode_buffer = NULL;
433 	struct ext2_block_group *bgd = NULL;
434 	struct ext_filesystem *fs = get_fs();
435 	char *journal_buffer = zalloc(fs->blksz);
436 	if (!journal_buffer)
437 		return -ENOMEM;
438 	/* get the block group descriptor table */
439 	bgd = (struct ext2_block_group *)fs->gdtable;
440 	status = ext4fs_read_inode(ext4fs_root, inodeno, &inode);
441 	if (status == 0)
442 		goto fail;
443 
444 	/* read the block no allocated to a file */
445 	no_blocks = le32_to_cpu(inode.size) / fs->blksz;
446 	if (le32_to_cpu(inode.size) % fs->blksz)
447 		no_blocks++;
448 
449 	if (le32_to_cpu(inode.flags) & EXT4_EXTENTS_FL) {
450 		/* FIXME delete extent index blocks, i.e. eh_depth >= 1 */
451 		struct ext4_extent_header *eh =
452 			(struct ext4_extent_header *)
453 				inode.b.blocks.dir_blocks;
454 		debug("del: dep=%d entries=%d\n", eh->eh_depth, eh->eh_entries);
455 	} else {
456 		delete_single_indirect_block(&inode);
457 		delete_double_indirect_block(&inode);
458 		delete_triple_indirect_block(&inode);
459 	}
460 
461 	/* release data blocks */
462 	for (i = 0; i < no_blocks; i++) {
463 		blknr = read_allocated_block(&inode, i);
464 		if (blknr == 0)
465 			continue;
466 		if (blknr < 0)
467 			goto fail;
468 		bg_idx = blknr / blk_per_grp;
469 		if (fs->blksz == 1024) {
470 			remainder = blknr % blk_per_grp;
471 			if (!remainder)
472 				bg_idx--;
473 		}
474 		ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx],
475 					bg_idx);
476 		debug("EXT4 Block releasing %ld: %d\n", blknr, bg_idx);
477 
478 		ext4fs_bg_free_blocks_inc(&bgd[bg_idx]);
479 		ext4fs_sb_free_blocks_inc(fs->sb);
480 		/* journal backup */
481 		if (prev_bg_bmap_idx != bg_idx) {
482 			uint32_t bgd_blknr = le32_to_cpu(bgd[bg_idx].block_id);
483 			status = ext4fs_devread((lbaint_t)bgd_blknr *
484 						fs->sect_perblk,
485 						0, fs->blksz,
486 						journal_buffer);
487 			if (status == 0)
488 				goto fail;
489 			if (ext4fs_log_journal(journal_buffer, bgd_blknr))
490 				goto fail;
491 			prev_bg_bmap_idx = bg_idx;
492 		}
493 	}
494 
495 	/* release inode */
496 	/* from the inode no to blockno */
497 	inodes_per_block = fs->blksz / fs->inodesz;
498 	ibmap_idx = inodeno / inode_per_grp;
499 
500 	/* get the block no */
501 	inodeno--;
502 	blkno = le32_to_cpu(bgd[ibmap_idx].inode_table_id) +
503 		(inodeno % inode_per_grp) / inodes_per_block;
504 
505 	/* get the offset of the inode */
506 	blkoff = ((inodeno) % inodes_per_block) * fs->inodesz;
507 
508 	/* read the block no containing the inode */
509 	read_buffer = zalloc(fs->blksz);
510 	if (!read_buffer)
511 		goto fail;
512 	start_block_address = read_buffer;
513 	status = ext4fs_devread((lbaint_t)blkno * fs->sect_perblk,
514 				0, fs->blksz, read_buffer);
515 	if (status == 0)
516 		goto fail;
517 
518 	if (ext4fs_log_journal(read_buffer, blkno))
519 		goto fail;
520 
521 	read_buffer = read_buffer + blkoff;
522 	inode_buffer = (struct ext2_inode *)read_buffer;
523 	memset(inode_buffer, '\0', fs->inodesz);
524 
525 	/* write the inode to original position in inode table */
526 	if (ext4fs_put_metadata(start_block_address, blkno))
527 		goto fail;
528 
529 	/* update the respective inode bitmaps */
530 	inodeno++;
531 	ext4fs_reset_inode_bmap(inodeno, fs->inode_bmaps[ibmap_idx], ibmap_idx);
532 	ext4fs_bg_free_inodes_inc(&bgd[ibmap_idx]);
533 	ext4fs_sb_free_inodes_inc(fs->sb);
534 	/* journal backup */
535 	memset(journal_buffer, '\0', fs->blksz);
536 	status = ext4fs_devread((lbaint_t)le32_to_cpu(bgd[ibmap_idx].inode_id) *
537 				fs->sect_perblk, 0, fs->blksz, journal_buffer);
538 	if (status == 0)
539 		goto fail;
540 	if (ext4fs_log_journal(journal_buffer, le32_to_cpu(bgd[ibmap_idx].inode_id)))
541 		goto fail;
542 
543 	ext4fs_update();
544 	ext4fs_deinit();
545 	ext4fs_reinit_global();
546 
547 	if (ext4fs_init() != 0) {
548 		printf("error in File System init\n");
549 		goto fail;
550 	}
551 
552 	free(start_block_address);
553 	free(journal_buffer);
554 
555 	return 0;
556 fail:
557 	free(start_block_address);
558 	free(journal_buffer);
559 
560 	return -1;
561 }
562 
563 int ext4fs_init(void)
564 {
565 	short status;
566 	int i;
567 	uint32_t real_free_blocks = 0;
568 	struct ext_filesystem *fs = get_fs();
569 
570 	/* populate fs */
571 	fs->blksz = EXT2_BLOCK_SIZE(ext4fs_root);
572 	fs->sect_perblk = fs->blksz >> fs->dev_desc->log2blksz;
573 
574 	/* get the superblock */
575 	fs->sb = zalloc(SUPERBLOCK_SIZE);
576 	if (!fs->sb)
577 		return -ENOMEM;
578 	if (!ext4_read_superblock((char *)fs->sb))
579 		goto fail;
580 
581 	/* init journal */
582 	if (ext4fs_init_journal())
583 		goto fail;
584 
585 	/* get total no of blockgroups */
586 	fs->no_blkgrp = (uint32_t)ext4fs_div_roundup(
587 			le32_to_cpu(ext4fs_root->sblock.total_blocks)
588 			- le32_to_cpu(ext4fs_root->sblock.first_data_block),
589 			le32_to_cpu(ext4fs_root->sblock.blocks_per_group));
590 
591 	/* get the block group descriptor table */
592 	fs->gdtable_blkno = ((EXT2_MIN_BLOCK_SIZE == fs->blksz) + 1);
593 	if (ext4fs_get_bgdtable() == -1) {
594 		printf("Error in getting the block group descriptor table\n");
595 		goto fail;
596 	}
597 	fs->bgd = (struct ext2_block_group *)fs->gdtable;
598 
599 	/* load all the available bitmap block of the partition */
600 	fs->blk_bmaps = zalloc(fs->no_blkgrp * sizeof(char *));
601 	if (!fs->blk_bmaps)
602 		goto fail;
603 	for (i = 0; i < fs->no_blkgrp; i++) {
604 		fs->blk_bmaps[i] = zalloc(fs->blksz);
605 		if (!fs->blk_bmaps[i])
606 			goto fail;
607 	}
608 
609 	for (i = 0; i < fs->no_blkgrp; i++) {
610 		status =
611 		    ext4fs_devread(
612 				   (lbaint_t)le32_to_cpu(fs->bgd[i].block_id) *
613 				   fs->sect_perblk, 0,
614 				   fs->blksz, (char *)fs->blk_bmaps[i]);
615 		if (status == 0)
616 			goto fail;
617 	}
618 
619 	/* load all the available inode bitmap of the partition */
620 	fs->inode_bmaps = zalloc(fs->no_blkgrp * sizeof(unsigned char *));
621 	if (!fs->inode_bmaps)
622 		goto fail;
623 	for (i = 0; i < fs->no_blkgrp; i++) {
624 		fs->inode_bmaps[i] = zalloc(fs->blksz);
625 		if (!fs->inode_bmaps[i])
626 			goto fail;
627 	}
628 
629 	for (i = 0; i < fs->no_blkgrp; i++) {
630 		status = ext4fs_devread(
631 					(lbaint_t)le32_to_cpu(fs->bgd[i].inode_id) *
632 					fs->sect_perblk,
633 					0, fs->blksz,
634 					(char *)fs->inode_bmaps[i]);
635 		if (status == 0)
636 			goto fail;
637 	}
638 
639 	/*
640 	 * check filesystem consistency with free blocks of file system
641 	 * some time we observed that superblock freeblocks does not match
642 	 * with the  blockgroups freeblocks when improper
643 	 * reboot of a linux kernel
644 	 */
645 	for (i = 0; i < fs->no_blkgrp; i++)
646 		real_free_blocks = real_free_blocks + le16_to_cpu(fs->bgd[i].free_blocks);
647 	if (real_free_blocks != le32_to_cpu(fs->sb->free_blocks))
648 		fs->sb->free_blocks = cpu_to_le32(real_free_blocks);
649 
650 	return 0;
651 fail:
652 	ext4fs_deinit();
653 
654 	return -1;
655 }
656 
657 void ext4fs_deinit(void)
658 {
659 	int i;
660 	struct ext2_inode inode_journal;
661 	struct journal_superblock_t *jsb;
662 	uint32_t blknr;
663 	struct ext_filesystem *fs = get_fs();
664 	uint32_t new_feature_incompat;
665 
666 	/* free journal */
667 	char *temp_buff = zalloc(fs->blksz);
668 	if (temp_buff) {
669 		ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO,
670 				  &inode_journal);
671 		blknr = read_allocated_block(&inode_journal,
672 					EXT2_JOURNAL_SUPERBLOCK);
673 		ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0, fs->blksz,
674 			       temp_buff);
675 		jsb = (struct journal_superblock_t *)temp_buff;
676 		jsb->s_start = 0;
677 		put_ext4((uint64_t) ((uint64_t)blknr * (uint64_t)fs->blksz),
678 			 (struct journal_superblock_t *)temp_buff, fs->blksz);
679 		free(temp_buff);
680 	}
681 	ext4fs_free_journal();
682 
683 	/* get the superblock */
684 	ext4_read_superblock((char *)fs->sb);
685 	new_feature_incompat = le32_to_cpu(fs->sb->feature_incompat);
686 	new_feature_incompat &= ~EXT3_FEATURE_INCOMPAT_RECOVER;
687 	fs->sb->feature_incompat = cpu_to_le32(new_feature_incompat);
688 	put_ext4((uint64_t)(SUPERBLOCK_SIZE),
689 		 (struct ext2_sblock *)fs->sb, (uint32_t)SUPERBLOCK_SIZE);
690 	free(fs->sb);
691 	fs->sb = NULL;
692 
693 	if (fs->blk_bmaps) {
694 		for (i = 0; i < fs->no_blkgrp; i++) {
695 			free(fs->blk_bmaps[i]);
696 			fs->blk_bmaps[i] = NULL;
697 		}
698 		free(fs->blk_bmaps);
699 		fs->blk_bmaps = NULL;
700 	}
701 
702 	if (fs->inode_bmaps) {
703 		for (i = 0; i < fs->no_blkgrp; i++) {
704 			free(fs->inode_bmaps[i]);
705 			fs->inode_bmaps[i] = NULL;
706 		}
707 		free(fs->inode_bmaps);
708 		fs->inode_bmaps = NULL;
709 	}
710 
711 
712 	free(fs->gdtable);
713 	fs->gdtable = NULL;
714 	fs->bgd = NULL;
715 	/*
716 	 * reinitiliazed the global inode and
717 	 * block bitmap first execution check variables
718 	 */
719 	fs->first_pass_ibmap = 0;
720 	fs->first_pass_bbmap = 0;
721 	fs->curr_inode_no = 0;
722 	fs->curr_blkno = 0;
723 }
724 
725 /*
726  * Write data to filesystem blocks. Uses same optimization for
727  * contigous sectors as ext4fs_read_file
728  */
729 static int ext4fs_write_file(struct ext2_inode *file_inode,
730 			     int pos, unsigned int len, char *buf)
731 {
732 	int i;
733 	int blockcnt;
734 	uint32_t filesize = le32_to_cpu(file_inode->size);
735 	struct ext_filesystem *fs = get_fs();
736 	int log2blksz = fs->dev_desc->log2blksz;
737 	int log2_fs_blocksize = LOG2_BLOCK_SIZE(ext4fs_root) - log2blksz;
738 	int previous_block_number = -1;
739 	int delayed_start = 0;
740 	int delayed_extent = 0;
741 	int delayed_next = 0;
742 	char *delayed_buf = NULL;
743 
744 	/* Adjust len so it we can't read past the end of the file. */
745 	if (len > filesize)
746 		len = filesize;
747 
748 	blockcnt = ((len + pos) + fs->blksz - 1) / fs->blksz;
749 
750 	for (i = pos / fs->blksz; i < blockcnt; i++) {
751 		long int blknr;
752 		int blockend = fs->blksz;
753 		int skipfirst = 0;
754 		blknr = read_allocated_block(file_inode, i);
755 		if (blknr <= 0)
756 			return -1;
757 
758 		blknr = blknr << log2_fs_blocksize;
759 
760 		if (blknr) {
761 			if (previous_block_number != -1) {
762 				if (delayed_next == blknr) {
763 					delayed_extent += blockend;
764 					delayed_next += blockend >> log2blksz;
765 				} else {	/* spill */
766 					put_ext4((uint64_t)
767 						 ((uint64_t)delayed_start << log2blksz),
768 						 delayed_buf,
769 						 (uint32_t) delayed_extent);
770 					previous_block_number = blknr;
771 					delayed_start = blknr;
772 					delayed_extent = blockend;
773 					delayed_buf = buf;
774 					delayed_next = blknr +
775 					    (blockend >> log2blksz);
776 				}
777 			} else {
778 				previous_block_number = blknr;
779 				delayed_start = blknr;
780 				delayed_extent = blockend;
781 				delayed_buf = buf;
782 				delayed_next = blknr +
783 				    (blockend >> log2blksz);
784 			}
785 		} else {
786 			if (previous_block_number != -1) {
787 				/* spill */
788 				put_ext4((uint64_t) ((uint64_t)delayed_start <<
789 						     log2blksz),
790 					 delayed_buf,
791 					 (uint32_t) delayed_extent);
792 				previous_block_number = -1;
793 			}
794 			memset(buf, 0, fs->blksz - skipfirst);
795 		}
796 		buf += fs->blksz - skipfirst;
797 	}
798 	if (previous_block_number != -1) {
799 		/* spill */
800 		put_ext4((uint64_t) ((uint64_t)delayed_start << log2blksz),
801 			 delayed_buf, (uint32_t) delayed_extent);
802 		previous_block_number = -1;
803 	}
804 
805 	return len;
806 }
807 
808 int ext4fs_write(const char *fname, unsigned char *buffer,
809 					unsigned long sizebytes)
810 {
811 	int ret = 0;
812 	struct ext2_inode *file_inode = NULL;
813 	unsigned char *inode_buffer = NULL;
814 	int parent_inodeno;
815 	int inodeno;
816 	time_t timestamp = 0;
817 
818 	uint64_t bytes_reqd_for_file;
819 	unsigned int blks_reqd_for_file;
820 	unsigned int blocks_remaining;
821 	int existing_file_inodeno;
822 	char *temp_ptr = NULL;
823 	long int itable_blkno;
824 	long int parent_itable_blkno;
825 	long int blkoff;
826 	struct ext2_sblock *sblock = &(ext4fs_root->sblock);
827 	unsigned int inodes_per_block;
828 	unsigned int ibmap_idx;
829 	struct ext_filesystem *fs = get_fs();
830 	ALLOC_CACHE_ALIGN_BUFFER(char, filename, 256);
831 	memset(filename, 0x00, 256);
832 
833 	g_parent_inode = zalloc(fs->inodesz);
834 	if (!g_parent_inode)
835 		goto fail;
836 
837 	if (ext4fs_init() != 0) {
838 		printf("error in File System init\n");
839 		return -1;
840 	}
841 	inodes_per_block = fs->blksz / fs->inodesz;
842 	parent_inodeno = ext4fs_get_parent_inode_num(fname, filename, F_FILE);
843 	if (parent_inodeno == -1)
844 		goto fail;
845 	if (ext4fs_iget(parent_inodeno, g_parent_inode))
846 		goto fail;
847 	/* do not mess up a directory using hash trees */
848 	if (le32_to_cpu(g_parent_inode->flags) & EXT4_INDEX_FL) {
849 		printf("hash tree directory\n");
850 		goto fail;
851 	}
852 	/* check if the filename is already present in root */
853 	existing_file_inodeno = ext4fs_filename_unlink(filename);
854 	if (existing_file_inodeno != -1) {
855 		ret = ext4fs_delete_file(existing_file_inodeno);
856 		fs->first_pass_bbmap = 0;
857 		fs->curr_blkno = 0;
858 
859 		fs->first_pass_ibmap = 0;
860 		fs->curr_inode_no = 0;
861 		if (ret)
862 			goto fail;
863 	}
864 	/* calucalate how many blocks required */
865 	bytes_reqd_for_file = sizebytes;
866 	blks_reqd_for_file = lldiv(bytes_reqd_for_file, fs->blksz);
867 	if (do_div(bytes_reqd_for_file, fs->blksz) != 0) {
868 		blks_reqd_for_file++;
869 		debug("total bytes for a file %u\n", blks_reqd_for_file);
870 	}
871 	blocks_remaining = blks_reqd_for_file;
872 	/* test for available space in partition */
873 	if (le32_to_cpu(fs->sb->free_blocks) < blks_reqd_for_file) {
874 		printf("Not enough space on partition !!!\n");
875 		goto fail;
876 	}
877 
878 	inodeno = ext4fs_update_parent_dentry(filename, FILETYPE_REG);
879 	if (inodeno == -1)
880 		goto fail;
881 	/* prepare file inode */
882 	inode_buffer = zalloc(fs->inodesz);
883 	if (!inode_buffer)
884 		goto fail;
885 	file_inode = (struct ext2_inode *)inode_buffer;
886 	file_inode->mode = cpu_to_le16(S_IFREG | S_IRWXU |
887 	    S_IRGRP | S_IROTH | S_IXGRP | S_IXOTH);
888 	/* ToDo: Update correct time */
889 	file_inode->mtime = cpu_to_le32(timestamp);
890 	file_inode->atime = cpu_to_le32(timestamp);
891 	file_inode->ctime = cpu_to_le32(timestamp);
892 	file_inode->nlinks = cpu_to_le16(1);
893 	file_inode->size = cpu_to_le32(sizebytes);
894 
895 	/* Allocate data blocks */
896 	ext4fs_allocate_blocks(file_inode, blocks_remaining,
897 			       &blks_reqd_for_file);
898 	file_inode->blockcnt = cpu_to_le32((blks_reqd_for_file * fs->blksz) >>
899 		fs->dev_desc->log2blksz);
900 
901 	temp_ptr = zalloc(fs->blksz);
902 	if (!temp_ptr)
903 		goto fail;
904 	ibmap_idx = inodeno / le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
905 	inodeno--;
906 	itable_blkno = le32_to_cpu(fs->bgd[ibmap_idx].inode_table_id) +
907 			(inodeno % le32_to_cpu(sblock->inodes_per_group)) /
908 			inodes_per_block;
909 	blkoff = (inodeno % inodes_per_block) * fs->inodesz;
910 	ext4fs_devread((lbaint_t)itable_blkno * fs->sect_perblk, 0, fs->blksz,
911 		       temp_ptr);
912 	if (ext4fs_log_journal(temp_ptr, itable_blkno))
913 		goto fail;
914 
915 	memcpy(temp_ptr + blkoff, inode_buffer, fs->inodesz);
916 	if (ext4fs_put_metadata(temp_ptr, itable_blkno))
917 		goto fail;
918 	/* copy the file content into data blocks */
919 	if (ext4fs_write_file(file_inode, 0, sizebytes, (char *)buffer) == -1) {
920 		printf("Error in copying content\n");
921 		/* FIXME: Deallocate data blocks */
922 		goto fail;
923 	}
924 	ibmap_idx = parent_inodeno / le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
925 	parent_inodeno--;
926 	parent_itable_blkno = le32_to_cpu(fs->bgd[ibmap_idx].inode_table_id) +
927 	    (parent_inodeno %
928 	     le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
929 	blkoff = (parent_inodeno % inodes_per_block) * fs->inodesz;
930 	if (parent_itable_blkno != itable_blkno) {
931 		memset(temp_ptr, '\0', fs->blksz);
932 		ext4fs_devread((lbaint_t)parent_itable_blkno * fs->sect_perblk,
933 			       0, fs->blksz, temp_ptr);
934 		if (ext4fs_log_journal(temp_ptr, parent_itable_blkno))
935 			goto fail;
936 
937 		memcpy(temp_ptr + blkoff, g_parent_inode, fs->inodesz);
938 		if (ext4fs_put_metadata(temp_ptr, parent_itable_blkno))
939 			goto fail;
940 	} else {
941 		/*
942 		 * If parent and child fall in same inode table block
943 		 * both should be kept in 1 buffer
944 		 */
945 		memcpy(temp_ptr + blkoff, g_parent_inode, fs->inodesz);
946 		gd_index--;
947 		if (ext4fs_put_metadata(temp_ptr, itable_blkno))
948 			goto fail;
949 	}
950 	ext4fs_update();
951 	ext4fs_deinit();
952 
953 	fs->first_pass_bbmap = 0;
954 	fs->curr_blkno = 0;
955 	fs->first_pass_ibmap = 0;
956 	fs->curr_inode_no = 0;
957 	free(inode_buffer);
958 	free(g_parent_inode);
959 	free(temp_ptr);
960 	g_parent_inode = NULL;
961 
962 	return 0;
963 fail:
964 	ext4fs_deinit();
965 	free(inode_buffer);
966 	free(g_parent_inode);
967 	free(temp_ptr);
968 	g_parent_inode = NULL;
969 
970 	return -1;
971 }
972 
973 int ext4_write_file(const char *filename, void *buf, loff_t offset,
974 		    loff_t len, loff_t *actwrite)
975 {
976 	int ret;
977 
978 	if (offset != 0) {
979 		printf("** Cannot support non-zero offset **\n");
980 		return -1;
981 	}
982 
983 	ret = ext4fs_write(filename, buf, len);
984 	if (ret) {
985 		printf("** Error ext4fs_write() **\n");
986 		goto fail;
987 	}
988 
989 	*actwrite = len;
990 
991 	return 0;
992 
993 fail:
994 	*actwrite = 0;
995 
996 	return -1;
997 }
998