xref: /rk3399_rockchip-uboot/fs/ext4/ext4_write.c (revision a0d767e2c1e40e781fdaa592f06f92614b4e5cdf)
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 		struct ext2fs_node *node_inode =
451 		    zalloc(sizeof(struct ext2fs_node));
452 		if (!node_inode)
453 			goto fail;
454 		node_inode->data = ext4fs_root;
455 		node_inode->ino = inodeno;
456 		node_inode->inode_read = 0;
457 		memcpy(&(node_inode->inode), &inode, sizeof(struct ext2_inode));
458 
459 		for (i = 0; i < no_blocks; i++) {
460 			blknr = read_allocated_block(&(node_inode->inode), i);
461 			bg_idx = blknr / blk_per_grp;
462 			if (fs->blksz == 1024) {
463 				remainder = blknr % blk_per_grp;
464 				if (!remainder)
465 					bg_idx--;
466 			}
467 			ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx],
468 						bg_idx);
469 			debug("EXT4_EXTENTS Block releasing %ld: %d\n",
470 			      blknr, bg_idx);
471 
472 			ext4fs_bg_free_blocks_inc(&bgd[bg_idx]);
473 			ext4fs_sb_free_blocks_inc(fs->sb);
474 
475 			/* journal backup */
476 			if (prev_bg_bmap_idx != bg_idx) {
477 				status =
478 				    ext4fs_devread(
479 						   (lbaint_t)le32_to_cpu(bgd[bg_idx].block_id) *
480 						   fs->sect_perblk, 0,
481 						   fs->blksz, journal_buffer);
482 				if (status == 0)
483 					goto fail;
484 				if (ext4fs_log_journal(journal_buffer,
485 							le32_to_cpu(bgd[bg_idx].block_id)))
486 					goto fail;
487 				prev_bg_bmap_idx = bg_idx;
488 			}
489 		}
490 		if (node_inode) {
491 			free(node_inode);
492 			node_inode = NULL;
493 		}
494 	} else {
495 
496 		delete_single_indirect_block(&inode);
497 		delete_double_indirect_block(&inode);
498 		delete_triple_indirect_block(&inode);
499 
500 		/* read the block no allocated to a file */
501 		no_blocks = le32_to_cpu(inode.size) / fs->blksz;
502 		if (le32_to_cpu(inode.size) % fs->blksz)
503 			no_blocks++;
504 		for (i = 0; i < no_blocks; i++) {
505 			blknr = read_allocated_block(&inode, i);
506 			bg_idx = blknr / blk_per_grp;
507 			if (fs->blksz == 1024) {
508 				remainder = blknr % blk_per_grp;
509 				if (!remainder)
510 					bg_idx--;
511 			}
512 			ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx],
513 						bg_idx);
514 			debug("ActualB releasing %ld: %d\n", blknr, bg_idx);
515 
516 			ext4fs_bg_free_blocks_inc(&bgd[bg_idx]);
517 			ext4fs_sb_free_blocks_inc(fs->sb);
518 			/* journal backup */
519 			if (prev_bg_bmap_idx != bg_idx) {
520 				memset(journal_buffer, '\0', fs->blksz);
521 				status = ext4fs_devread(
522 							(lbaint_t)le32_to_cpu(bgd[bg_idx].block_id)
523 							* fs->sect_perblk,
524 							0, fs->blksz,
525 							journal_buffer);
526 				if (status == 0)
527 					goto fail;
528 				if (ext4fs_log_journal(journal_buffer,
529 						le32_to_cpu(bgd[bg_idx].block_id)))
530 					goto fail;
531 				prev_bg_bmap_idx = bg_idx;
532 			}
533 		}
534 	}
535 
536 	/* from the inode no to blockno */
537 	inodes_per_block = fs->blksz / fs->inodesz;
538 	ibmap_idx = inodeno / inode_per_grp;
539 
540 	/* get the block no */
541 	inodeno--;
542 	blkno = le32_to_cpu(bgd[ibmap_idx].inode_table_id) +
543 		(inodeno % inode_per_grp) / inodes_per_block;
544 
545 	/* get the offset of the inode */
546 	blkoff = ((inodeno) % inodes_per_block) * fs->inodesz;
547 
548 	/* read the block no containing the inode */
549 	read_buffer = zalloc(fs->blksz);
550 	if (!read_buffer)
551 		goto fail;
552 	start_block_address = read_buffer;
553 	status = ext4fs_devread((lbaint_t)blkno * fs->sect_perblk,
554 				0, fs->blksz, read_buffer);
555 	if (status == 0)
556 		goto fail;
557 
558 	if (ext4fs_log_journal(read_buffer, blkno))
559 		goto fail;
560 
561 	read_buffer = read_buffer + blkoff;
562 	inode_buffer = (struct ext2_inode *)read_buffer;
563 	memset(inode_buffer, '\0', sizeof(struct ext2_inode));
564 
565 	/* write the inode to original position in inode table */
566 	if (ext4fs_put_metadata(start_block_address, blkno))
567 		goto fail;
568 
569 	/* update the respective inode bitmaps */
570 	inodeno++;
571 	ext4fs_reset_inode_bmap(inodeno, fs->inode_bmaps[ibmap_idx], ibmap_idx);
572 	ext4fs_bg_free_inodes_inc(&bgd[ibmap_idx]);
573 	ext4fs_sb_free_inodes_inc(fs->sb);
574 	/* journal backup */
575 	memset(journal_buffer, '\0', fs->blksz);
576 	status = ext4fs_devread((lbaint_t)le32_to_cpu(bgd[ibmap_idx].inode_id) *
577 				fs->sect_perblk, 0, fs->blksz, journal_buffer);
578 	if (status == 0)
579 		goto fail;
580 	if (ext4fs_log_journal(journal_buffer, le32_to_cpu(bgd[ibmap_idx].inode_id)))
581 		goto fail;
582 
583 	ext4fs_update();
584 	ext4fs_deinit();
585 	ext4fs_reinit_global();
586 
587 	if (ext4fs_init() != 0) {
588 		printf("error in File System init\n");
589 		goto fail;
590 	}
591 
592 	free(start_block_address);
593 	free(journal_buffer);
594 
595 	return 0;
596 fail:
597 	free(start_block_address);
598 	free(journal_buffer);
599 
600 	return -1;
601 }
602 
603 int ext4fs_init(void)
604 {
605 	short status;
606 	int i;
607 	uint32_t real_free_blocks = 0;
608 	struct ext_filesystem *fs = get_fs();
609 
610 	/* populate fs */
611 	fs->blksz = EXT2_BLOCK_SIZE(ext4fs_root);
612 	fs->inodesz = INODE_SIZE_FILESYSTEM(ext4fs_root);
613 	fs->sect_perblk = fs->blksz >> fs->dev_desc->log2blksz;
614 
615 	/* get the superblock */
616 	fs->sb = zalloc(SUPERBLOCK_SIZE);
617 	if (!fs->sb)
618 		return -ENOMEM;
619 	if (!ext4_read_superblock((char *)fs->sb))
620 		goto fail;
621 
622 	/* init journal */
623 	if (ext4fs_init_journal())
624 		goto fail;
625 
626 	/* get total no of blockgroups */
627 	fs->no_blkgrp = (uint32_t)ext4fs_div_roundup(
628 			le32_to_cpu(ext4fs_root->sblock.total_blocks)
629 			- le32_to_cpu(ext4fs_root->sblock.first_data_block),
630 			le32_to_cpu(ext4fs_root->sblock.blocks_per_group));
631 
632 	/* get the block group descriptor table */
633 	fs->gdtable_blkno = ((EXT2_MIN_BLOCK_SIZE == fs->blksz) + 1);
634 	if (ext4fs_get_bgdtable() == -1) {
635 		printf("Error in getting the block group descriptor table\n");
636 		goto fail;
637 	}
638 	fs->bgd = (struct ext2_block_group *)fs->gdtable;
639 
640 	/* load all the available bitmap block of the partition */
641 	fs->blk_bmaps = zalloc(fs->no_blkgrp * sizeof(char *));
642 	if (!fs->blk_bmaps)
643 		goto fail;
644 	for (i = 0; i < fs->no_blkgrp; i++) {
645 		fs->blk_bmaps[i] = zalloc(fs->blksz);
646 		if (!fs->blk_bmaps[i])
647 			goto fail;
648 	}
649 
650 	for (i = 0; i < fs->no_blkgrp; i++) {
651 		status =
652 		    ext4fs_devread(
653 				   (lbaint_t)le32_to_cpu(fs->bgd[i].block_id) *
654 				   fs->sect_perblk, 0,
655 				   fs->blksz, (char *)fs->blk_bmaps[i]);
656 		if (status == 0)
657 			goto fail;
658 	}
659 
660 	/* load all the available inode bitmap of the partition */
661 	fs->inode_bmaps = zalloc(fs->no_blkgrp * sizeof(unsigned char *));
662 	if (!fs->inode_bmaps)
663 		goto fail;
664 	for (i = 0; i < fs->no_blkgrp; i++) {
665 		fs->inode_bmaps[i] = zalloc(fs->blksz);
666 		if (!fs->inode_bmaps[i])
667 			goto fail;
668 	}
669 
670 	for (i = 0; i < fs->no_blkgrp; i++) {
671 		status = ext4fs_devread(
672 					(lbaint_t)le32_to_cpu(fs->bgd[i].inode_id) *
673 					fs->sect_perblk,
674 					0, fs->blksz,
675 					(char *)fs->inode_bmaps[i]);
676 		if (status == 0)
677 			goto fail;
678 	}
679 
680 	/*
681 	 * check filesystem consistency with free blocks of file system
682 	 * some time we observed that superblock freeblocks does not match
683 	 * with the  blockgroups freeblocks when improper
684 	 * reboot of a linux kernel
685 	 */
686 	for (i = 0; i < fs->no_blkgrp; i++)
687 		real_free_blocks = real_free_blocks + le16_to_cpu(fs->bgd[i].free_blocks);
688 	if (real_free_blocks != le32_to_cpu(fs->sb->free_blocks))
689 		fs->sb->free_blocks = cpu_to_le32(real_free_blocks);
690 
691 	return 0;
692 fail:
693 	ext4fs_deinit();
694 
695 	return -1;
696 }
697 
698 void ext4fs_deinit(void)
699 {
700 	int i;
701 	struct ext2_inode inode_journal;
702 	struct journal_superblock_t *jsb;
703 	uint32_t blknr;
704 	struct ext_filesystem *fs = get_fs();
705 	uint32_t new_feature_incompat;
706 
707 	/* free journal */
708 	char *temp_buff = zalloc(fs->blksz);
709 	if (temp_buff) {
710 		ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO,
711 				  &inode_journal);
712 		blknr = read_allocated_block(&inode_journal,
713 					EXT2_JOURNAL_SUPERBLOCK);
714 		ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0, fs->blksz,
715 			       temp_buff);
716 		jsb = (struct journal_superblock_t *)temp_buff;
717 		jsb->s_start = 0;
718 		put_ext4((uint64_t) ((uint64_t)blknr * (uint64_t)fs->blksz),
719 			 (struct journal_superblock_t *)temp_buff, fs->blksz);
720 		free(temp_buff);
721 	}
722 	ext4fs_free_journal();
723 
724 	/* get the superblock */
725 	ext4_read_superblock((char *)fs->sb);
726 	new_feature_incompat = le32_to_cpu(fs->sb->feature_incompat);
727 	new_feature_incompat &= ~EXT3_FEATURE_INCOMPAT_RECOVER;
728 	fs->sb->feature_incompat = cpu_to_le32(new_feature_incompat);
729 	put_ext4((uint64_t)(SUPERBLOCK_SIZE),
730 		 (struct ext2_sblock *)fs->sb, (uint32_t)SUPERBLOCK_SIZE);
731 	free(fs->sb);
732 	fs->sb = NULL;
733 
734 	if (fs->blk_bmaps) {
735 		for (i = 0; i < fs->no_blkgrp; i++) {
736 			free(fs->blk_bmaps[i]);
737 			fs->blk_bmaps[i] = NULL;
738 		}
739 		free(fs->blk_bmaps);
740 		fs->blk_bmaps = NULL;
741 	}
742 
743 	if (fs->inode_bmaps) {
744 		for (i = 0; i < fs->no_blkgrp; i++) {
745 			free(fs->inode_bmaps[i]);
746 			fs->inode_bmaps[i] = NULL;
747 		}
748 		free(fs->inode_bmaps);
749 		fs->inode_bmaps = NULL;
750 	}
751 
752 
753 	free(fs->gdtable);
754 	fs->gdtable = NULL;
755 	fs->bgd = NULL;
756 	/*
757 	 * reinitiliazed the global inode and
758 	 * block bitmap first execution check variables
759 	 */
760 	fs->first_pass_ibmap = 0;
761 	fs->first_pass_bbmap = 0;
762 	fs->curr_inode_no = 0;
763 	fs->curr_blkno = 0;
764 }
765 
766 static int ext4fs_write_file(struct ext2_inode *file_inode,
767 			     int pos, unsigned int len, char *buf)
768 {
769 	int i;
770 	int blockcnt;
771 	uint32_t filesize = le32_to_cpu(file_inode->size);
772 	struct ext_filesystem *fs = get_fs();
773 	int log2blksz = fs->dev_desc->log2blksz;
774 	int log2_fs_blocksize = LOG2_BLOCK_SIZE(ext4fs_root) - log2blksz;
775 	int previous_block_number = -1;
776 	int delayed_start = 0;
777 	int delayed_extent = 0;
778 	int delayed_next = 0;
779 	char *delayed_buf = NULL;
780 
781 	/* Adjust len so it we can't read past the end of the file. */
782 	if (len > filesize)
783 		len = filesize;
784 
785 	blockcnt = ((len + pos) + fs->blksz - 1) / fs->blksz;
786 
787 	for (i = pos / fs->blksz; i < blockcnt; i++) {
788 		long int blknr;
789 		int blockend = fs->blksz;
790 		int skipfirst = 0;
791 		blknr = read_allocated_block(file_inode, i);
792 		if (blknr < 0)
793 			return -1;
794 
795 		blknr = blknr << log2_fs_blocksize;
796 
797 		if (blknr) {
798 			if (previous_block_number != -1) {
799 				if (delayed_next == blknr) {
800 					delayed_extent += blockend;
801 					delayed_next += blockend >> log2blksz;
802 				} else {	/* spill */
803 					put_ext4((uint64_t)
804 						 ((uint64_t)delayed_start << log2blksz),
805 						 delayed_buf,
806 						 (uint32_t) delayed_extent);
807 					previous_block_number = blknr;
808 					delayed_start = blknr;
809 					delayed_extent = blockend;
810 					delayed_buf = buf;
811 					delayed_next = blknr +
812 					    (blockend >> log2blksz);
813 				}
814 			} else {
815 				previous_block_number = blknr;
816 				delayed_start = blknr;
817 				delayed_extent = blockend;
818 				delayed_buf = buf;
819 				delayed_next = blknr +
820 				    (blockend >> log2blksz);
821 			}
822 		} else {
823 			if (previous_block_number != -1) {
824 				/* spill */
825 				put_ext4((uint64_t) ((uint64_t)delayed_start <<
826 						     log2blksz),
827 					 delayed_buf,
828 					 (uint32_t) delayed_extent);
829 				previous_block_number = -1;
830 			}
831 			memset(buf, 0, fs->blksz - skipfirst);
832 		}
833 		buf += fs->blksz - skipfirst;
834 	}
835 	if (previous_block_number != -1) {
836 		/* spill */
837 		put_ext4((uint64_t) ((uint64_t)delayed_start << log2blksz),
838 			 delayed_buf, (uint32_t) delayed_extent);
839 		previous_block_number = -1;
840 	}
841 
842 	return len;
843 }
844 
845 int ext4fs_write(const char *fname, unsigned char *buffer,
846 					unsigned long sizebytes)
847 {
848 	int ret = 0;
849 	struct ext2_inode *file_inode = NULL;
850 	unsigned char *inode_buffer = NULL;
851 	int parent_inodeno;
852 	int inodeno;
853 	time_t timestamp = 0;
854 
855 	uint64_t bytes_reqd_for_file;
856 	unsigned int blks_reqd_for_file;
857 	unsigned int blocks_remaining;
858 	int existing_file_inodeno;
859 	char *temp_ptr = NULL;
860 	long int itable_blkno;
861 	long int parent_itable_blkno;
862 	long int blkoff;
863 	struct ext2_sblock *sblock = &(ext4fs_root->sblock);
864 	unsigned int inodes_per_block;
865 	unsigned int ibmap_idx;
866 	struct ext_filesystem *fs = get_fs();
867 	ALLOC_CACHE_ALIGN_BUFFER(char, filename, 256);
868 	memset(filename, 0x00, 256);
869 
870 	g_parent_inode = zalloc(sizeof(struct ext2_inode));
871 	if (!g_parent_inode)
872 		goto fail;
873 
874 	if (ext4fs_init() != 0) {
875 		printf("error in File System init\n");
876 		return -1;
877 	}
878 	inodes_per_block = fs->blksz / fs->inodesz;
879 	parent_inodeno = ext4fs_get_parent_inode_num(fname, filename, F_FILE);
880 	if (parent_inodeno == -1)
881 		goto fail;
882 	if (ext4fs_iget(parent_inodeno, g_parent_inode))
883 		goto fail;
884 	/* check if the filename is already present in root */
885 	existing_file_inodeno = ext4fs_filename_unlink(filename);
886 	if (existing_file_inodeno != -1) {
887 		ret = ext4fs_delete_file(existing_file_inodeno);
888 		fs->first_pass_bbmap = 0;
889 		fs->curr_blkno = 0;
890 
891 		fs->first_pass_ibmap = 0;
892 		fs->curr_inode_no = 0;
893 		if (ret)
894 			goto fail;
895 	}
896 	/* calucalate how many blocks required */
897 	bytes_reqd_for_file = sizebytes;
898 	blks_reqd_for_file = lldiv(bytes_reqd_for_file, fs->blksz);
899 	if (do_div(bytes_reqd_for_file, fs->blksz) != 0) {
900 		blks_reqd_for_file++;
901 		debug("total bytes for a file %u\n", blks_reqd_for_file);
902 	}
903 	blocks_remaining = blks_reqd_for_file;
904 	/* test for available space in partition */
905 	if (le32_to_cpu(fs->sb->free_blocks) < blks_reqd_for_file) {
906 		printf("Not enough space on partition !!!\n");
907 		goto fail;
908 	}
909 
910 	inodeno = ext4fs_update_parent_dentry(filename, FILETYPE_REG);
911 	if (inodeno == -1)
912 		goto fail;
913 	/* prepare file inode */
914 	inode_buffer = zalloc(fs->inodesz);
915 	if (!inode_buffer)
916 		goto fail;
917 	file_inode = (struct ext2_inode *)inode_buffer;
918 	file_inode->mode = cpu_to_le16(S_IFREG | S_IRWXU |
919 	    S_IRGRP | S_IROTH | S_IXGRP | S_IXOTH);
920 	/* ToDo: Update correct time */
921 	file_inode->mtime = cpu_to_le32(timestamp);
922 	file_inode->atime = cpu_to_le32(timestamp);
923 	file_inode->ctime = cpu_to_le32(timestamp);
924 	file_inode->nlinks = cpu_to_le16(1);
925 	file_inode->size = cpu_to_le32(sizebytes);
926 
927 	/* Allocate data blocks */
928 	ext4fs_allocate_blocks(file_inode, blocks_remaining,
929 			       &blks_reqd_for_file);
930 	file_inode->blockcnt = cpu_to_le32((blks_reqd_for_file * fs->blksz) >>
931 		fs->dev_desc->log2blksz);
932 
933 	temp_ptr = zalloc(fs->blksz);
934 	if (!temp_ptr)
935 		goto fail;
936 	ibmap_idx = inodeno / le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
937 	inodeno--;
938 	itable_blkno = le32_to_cpu(fs->bgd[ibmap_idx].inode_table_id) +
939 			(inodeno % le32_to_cpu(sblock->inodes_per_group)) /
940 			inodes_per_block;
941 	blkoff = (inodeno % inodes_per_block) * fs->inodesz;
942 	ext4fs_devread((lbaint_t)itable_blkno * fs->sect_perblk, 0, fs->blksz,
943 		       temp_ptr);
944 	if (ext4fs_log_journal(temp_ptr, itable_blkno))
945 		goto fail;
946 
947 	memcpy(temp_ptr + blkoff, inode_buffer, fs->inodesz);
948 	if (ext4fs_put_metadata(temp_ptr, itable_blkno))
949 		goto fail;
950 	/* copy the file content into data blocks */
951 	if (ext4fs_write_file(file_inode, 0, sizebytes, (char *)buffer) == -1) {
952 		printf("Error in copying content\n");
953 		goto fail;
954 	}
955 	ibmap_idx = parent_inodeno / le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
956 	parent_inodeno--;
957 	parent_itable_blkno = le32_to_cpu(fs->bgd[ibmap_idx].inode_table_id) +
958 	    (parent_inodeno %
959 	     le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
960 	blkoff = (parent_inodeno % inodes_per_block) * fs->inodesz;
961 	if (parent_itable_blkno != itable_blkno) {
962 		memset(temp_ptr, '\0', fs->blksz);
963 		ext4fs_devread((lbaint_t)parent_itable_blkno * fs->sect_perblk,
964 			       0, fs->blksz, temp_ptr);
965 		if (ext4fs_log_journal(temp_ptr, parent_itable_blkno))
966 			goto fail;
967 
968 		memcpy(temp_ptr + blkoff, g_parent_inode,
969 			sizeof(struct ext2_inode));
970 		if (ext4fs_put_metadata(temp_ptr, parent_itable_blkno))
971 			goto fail;
972 		free(temp_ptr);
973 	} else {
974 		/*
975 		 * If parent and child fall in same inode table block
976 		 * both should be kept in 1 buffer
977 		 */
978 		memcpy(temp_ptr + blkoff, g_parent_inode,
979 		       sizeof(struct ext2_inode));
980 		gd_index--;
981 		if (ext4fs_put_metadata(temp_ptr, itable_blkno))
982 			goto fail;
983 		free(temp_ptr);
984 	}
985 	ext4fs_update();
986 	ext4fs_deinit();
987 
988 	fs->first_pass_bbmap = 0;
989 	fs->curr_blkno = 0;
990 	fs->first_pass_ibmap = 0;
991 	fs->curr_inode_no = 0;
992 	free(inode_buffer);
993 	free(g_parent_inode);
994 	g_parent_inode = NULL;
995 
996 	return 0;
997 fail:
998 	ext4fs_deinit();
999 	free(inode_buffer);
1000 	free(g_parent_inode);
1001 	g_parent_inode = NULL;
1002 
1003 	return -1;
1004 }
1005 
1006 int ext4_write_file(const char *filename, void *buf, loff_t offset,
1007 		    loff_t len, loff_t *actwrite)
1008 {
1009 	int ret;
1010 
1011 	if (offset != 0) {
1012 		printf("** Cannot support non-zero offset **\n");
1013 		return -1;
1014 	}
1015 
1016 	ret = ext4fs_write(filename, buf, len);
1017 	if (ret) {
1018 		printf("** Error ext4fs_write() **\n");
1019 		goto fail;
1020 	}
1021 
1022 	*actwrite = len;
1023 
1024 	return 0;
1025 
1026 fail:
1027 	*actwrite = 0;
1028 
1029 	return -1;
1030 }
1031