xref: /openbmc/u-boot/fs/yaffs2/yaffs_guts.c (revision ee5f2490)
1 /*
2  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
3  *
4  * Copyright (C) 2002-2011 Aleph One Ltd.
5  *   for Toby Churchill Ltd and Brightstar Engineering
6  *
7  * Created by Charles Manning <charles@aleph1.co.uk>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 
14 #include "yportenv.h"
15 #include "yaffs_trace.h"
16 
17 #include "yaffs_guts.h"
18 #include "yaffs_getblockinfo.h"
19 #include "yaffs_tagscompat.h"
20 #include "yaffs_nand.h"
21 #include "yaffs_yaffs1.h"
22 #include "yaffs_yaffs2.h"
23 #include "yaffs_bitmap.h"
24 #include "yaffs_verify.h"
25 #include "yaffs_nand.h"
26 #include "yaffs_packedtags2.h"
27 #include "yaffs_nameval.h"
28 #include "yaffs_allocator.h"
29 #include "yaffs_attribs.h"
30 #include "yaffs_summary.h"
31 
32 /* Note YAFFS_GC_GOOD_ENOUGH must be <= YAFFS_GC_PASSIVE_THRESHOLD */
33 #define YAFFS_GC_GOOD_ENOUGH 2
34 #define YAFFS_GC_PASSIVE_THRESHOLD 4
35 
36 #include "yaffs_ecc.h"
37 
38 /* Forward declarations */
39 
40 static int yaffs_wr_data_obj(struct yaffs_obj *in, int inode_chunk,
41 			     const u8 *buffer, int n_bytes, int use_reserve);
42 
43 
44 
45 /* Function to calculate chunk and offset */
46 
yaffs_addr_to_chunk(struct yaffs_dev * dev,loff_t addr,int * chunk_out,u32 * offset_out)47 void yaffs_addr_to_chunk(struct yaffs_dev *dev, loff_t addr,
48 				int *chunk_out, u32 *offset_out)
49 {
50 	int chunk;
51 	u32 offset;
52 
53 	chunk = (u32) (addr >> dev->chunk_shift);
54 
55 	if (dev->chunk_div == 1) {
56 		/* easy power of 2 case */
57 		offset = (u32) (addr & dev->chunk_mask);
58 	} else {
59 		/* Non power-of-2 case */
60 
61 		loff_t chunk_base;
62 
63 		chunk /= dev->chunk_div;
64 
65 		chunk_base = ((loff_t) chunk) * dev->data_bytes_per_chunk;
66 		offset = (u32) (addr - chunk_base);
67 	}
68 
69 	*chunk_out = chunk;
70 	*offset_out = offset;
71 }
72 
73 /* Function to return the number of shifts for a power of 2 greater than or
74  * equal to the given number
75  * Note we don't try to cater for all possible numbers and this does not have to
76  * be hellishly efficient.
77  */
78 
calc_shifts_ceiling(u32 x)79 static inline u32 calc_shifts_ceiling(u32 x)
80 {
81 	int extra_bits;
82 	int shifts;
83 
84 	shifts = extra_bits = 0;
85 
86 	while (x > 1) {
87 		if (x & 1)
88 			extra_bits++;
89 		x >>= 1;
90 		shifts++;
91 	}
92 
93 	if (extra_bits)
94 		shifts++;
95 
96 	return shifts;
97 }
98 
99 /* Function to return the number of shifts to get a 1 in bit 0
100  */
101 
calc_shifts(u32 x)102 static inline u32 calc_shifts(u32 x)
103 {
104 	u32 shifts;
105 
106 	shifts = 0;
107 
108 	if (!x)
109 		return 0;
110 
111 	while (!(x & 1)) {
112 		x >>= 1;
113 		shifts++;
114 	}
115 
116 	return shifts;
117 }
118 
119 /*
120  * Temporary buffer manipulations.
121  */
122 
yaffs_init_tmp_buffers(struct yaffs_dev * dev)123 static int yaffs_init_tmp_buffers(struct yaffs_dev *dev)
124 {
125 	int i;
126 	u8 *buf = (u8 *) 1;
127 
128 	memset(dev->temp_buffer, 0, sizeof(dev->temp_buffer));
129 
130 	for (i = 0; buf && i < YAFFS_N_TEMP_BUFFERS; i++) {
131 		dev->temp_buffer[i].in_use = 0;
132 		buf = kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
133 		dev->temp_buffer[i].buffer = buf;
134 	}
135 
136 	return buf ? YAFFS_OK : YAFFS_FAIL;
137 }
138 
yaffs_get_temp_buffer(struct yaffs_dev * dev)139 u8 *yaffs_get_temp_buffer(struct yaffs_dev * dev)
140 {
141 	int i;
142 
143 	dev->temp_in_use++;
144 	if (dev->temp_in_use > dev->max_temp)
145 		dev->max_temp = dev->temp_in_use;
146 
147 	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
148 		if (dev->temp_buffer[i].in_use == 0) {
149 			dev->temp_buffer[i].in_use = 1;
150 			return dev->temp_buffer[i].buffer;
151 		}
152 	}
153 
154 	yaffs_trace(YAFFS_TRACE_BUFFERS, "Out of temp buffers");
155 	/*
156 	 * If we got here then we have to allocate an unmanaged one
157 	 * This is not good.
158 	 */
159 
160 	dev->unmanaged_buffer_allocs++;
161 	return kmalloc(dev->data_bytes_per_chunk, GFP_NOFS);
162 
163 }
164 
yaffs_release_temp_buffer(struct yaffs_dev * dev,u8 * buffer)165 void yaffs_release_temp_buffer(struct yaffs_dev *dev, u8 *buffer)
166 {
167 	int i;
168 
169 	dev->temp_in_use--;
170 
171 	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
172 		if (dev->temp_buffer[i].buffer == buffer) {
173 			dev->temp_buffer[i].in_use = 0;
174 			return;
175 		}
176 	}
177 
178 	if (buffer) {
179 		/* assume it is an unmanaged one. */
180 		yaffs_trace(YAFFS_TRACE_BUFFERS,
181 			"Releasing unmanaged temp buffer");
182 		kfree(buffer);
183 		dev->unmanaged_buffer_deallocs++;
184 	}
185 
186 }
187 
188 /*
189  * Determine if we have a managed buffer.
190  */
yaffs_is_managed_tmp_buffer(struct yaffs_dev * dev,const u8 * buffer)191 int yaffs_is_managed_tmp_buffer(struct yaffs_dev *dev, const u8 *buffer)
192 {
193 	int i;
194 
195 	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
196 		if (dev->temp_buffer[i].buffer == buffer)
197 			return 1;
198 	}
199 
200 	for (i = 0; i < dev->param.n_caches; i++) {
201 		if (dev->cache[i].data == buffer)
202 			return 1;
203 	}
204 
205 	if (buffer == dev->checkpt_buffer)
206 		return 1;
207 
208 	yaffs_trace(YAFFS_TRACE_ALWAYS,
209 	  "yaffs: unmaged buffer detected.");
210 	return 0;
211 }
212 
213 /*
214  * Functions for robustisizing TODO
215  *
216  */
217 
yaffs_handle_chunk_wr_ok(struct yaffs_dev * dev,int nand_chunk,const u8 * data,const struct yaffs_ext_tags * tags)218 static void yaffs_handle_chunk_wr_ok(struct yaffs_dev *dev, int nand_chunk,
219 				     const u8 *data,
220 				     const struct yaffs_ext_tags *tags)
221 {
222 }
223 
yaffs_handle_chunk_update(struct yaffs_dev * dev,int nand_chunk,const struct yaffs_ext_tags * tags)224 static void yaffs_handle_chunk_update(struct yaffs_dev *dev, int nand_chunk,
225 				      const struct yaffs_ext_tags *tags)
226 {
227 }
228 
yaffs_handle_chunk_error(struct yaffs_dev * dev,struct yaffs_block_info * bi)229 void yaffs_handle_chunk_error(struct yaffs_dev *dev,
230 			      struct yaffs_block_info *bi)
231 {
232 	if (!bi->gc_prioritise) {
233 		bi->gc_prioritise = 1;
234 		dev->has_pending_prioritised_gc = 1;
235 		bi->chunk_error_strikes++;
236 
237 		if (bi->chunk_error_strikes > 3) {
238 			bi->needs_retiring = 1;	/* Too many stikes, so retire */
239 			yaffs_trace(YAFFS_TRACE_ALWAYS,
240 				"yaffs: Block struck out");
241 
242 		}
243 	}
244 }
245 
yaffs_handle_chunk_wr_error(struct yaffs_dev * dev,int nand_chunk,int erased_ok)246 static void yaffs_handle_chunk_wr_error(struct yaffs_dev *dev, int nand_chunk,
247 					int erased_ok)
248 {
249 	int flash_block = nand_chunk / dev->param.chunks_per_block;
250 	struct yaffs_block_info *bi = yaffs_get_block_info(dev, flash_block);
251 
252 	yaffs_handle_chunk_error(dev, bi);
253 
254 	if (erased_ok) {
255 		/* Was an actual write failure,
256 		 * so mark the block for retirement.*/
257 		bi->needs_retiring = 1;
258 		yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
259 		  "**>> Block %d needs retiring", flash_block);
260 	}
261 
262 	/* Delete the chunk */
263 	yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
264 	yaffs_skip_rest_of_block(dev);
265 }
266 
267 /*
268  * Verification code
269  */
270 
271 /*
272  *  Simple hash function. Needs to have a reasonable spread
273  */
274 
yaffs_hash_fn(int n)275 static inline int yaffs_hash_fn(int n)
276 {
277 	if (n < 0)
278 		n = -n;
279 	return n % YAFFS_NOBJECT_BUCKETS;
280 }
281 
282 /*
283  * Access functions to useful fake objects.
284  * Note that root might have a presence in NAND if permissions are set.
285  */
286 
yaffs_root(struct yaffs_dev * dev)287 struct yaffs_obj *yaffs_root(struct yaffs_dev *dev)
288 {
289 	return dev->root_dir;
290 }
291 
yaffs_lost_n_found(struct yaffs_dev * dev)292 struct yaffs_obj *yaffs_lost_n_found(struct yaffs_dev *dev)
293 {
294 	return dev->lost_n_found;
295 }
296 
297 /*
298  *  Erased NAND checking functions
299  */
300 
yaffs_check_ff(u8 * buffer,int n_bytes)301 int yaffs_check_ff(u8 *buffer, int n_bytes)
302 {
303 	/* Horrible, slow implementation */
304 	while (n_bytes--) {
305 		if (*buffer != 0xff)
306 			return 0;
307 		buffer++;
308 	}
309 	return 1;
310 }
311 
yaffs_check_chunk_erased(struct yaffs_dev * dev,int nand_chunk)312 static int yaffs_check_chunk_erased(struct yaffs_dev *dev, int nand_chunk)
313 {
314 	int retval = YAFFS_OK;
315 	u8 *data = yaffs_get_temp_buffer(dev);
316 	struct yaffs_ext_tags tags;
317 
318 	yaffs_rd_chunk_tags_nand(dev, nand_chunk, data, &tags);
319 
320 	if (tags.ecc_result > YAFFS_ECC_RESULT_NO_ERROR)
321 		retval = YAFFS_FAIL;
322 
323 	if (!yaffs_check_ff(data, dev->data_bytes_per_chunk) ||
324 		tags.chunk_used) {
325 		yaffs_trace(YAFFS_TRACE_NANDACCESS,
326 			"Chunk %d not erased", nand_chunk);
327 		retval = YAFFS_FAIL;
328 	}
329 
330 	yaffs_release_temp_buffer(dev, data);
331 
332 	return retval;
333 
334 }
335 
yaffs_verify_chunk_written(struct yaffs_dev * dev,int nand_chunk,const u8 * data,struct yaffs_ext_tags * tags)336 static int yaffs_verify_chunk_written(struct yaffs_dev *dev,
337 				      int nand_chunk,
338 				      const u8 *data,
339 				      struct yaffs_ext_tags *tags)
340 {
341 	int retval = YAFFS_OK;
342 	struct yaffs_ext_tags temp_tags;
343 	u8 *buffer = yaffs_get_temp_buffer(dev);
344 
345 	yaffs_rd_chunk_tags_nand(dev, nand_chunk, buffer, &temp_tags);
346 	if (memcmp(buffer, data, dev->data_bytes_per_chunk) ||
347 	    temp_tags.obj_id != tags->obj_id ||
348 	    temp_tags.chunk_id != tags->chunk_id ||
349 	    temp_tags.n_bytes != tags->n_bytes)
350 		retval = YAFFS_FAIL;
351 
352 	yaffs_release_temp_buffer(dev, buffer);
353 
354 	return retval;
355 }
356 
357 
yaffs_check_alloc_available(struct yaffs_dev * dev,int n_chunks)358 int yaffs_check_alloc_available(struct yaffs_dev *dev, int n_chunks)
359 {
360 	int reserved_chunks;
361 	int reserved_blocks = dev->param.n_reserved_blocks;
362 	int checkpt_blocks;
363 
364 	checkpt_blocks = yaffs_calc_checkpt_blocks_required(dev);
365 
366 	reserved_chunks =
367 	    (reserved_blocks + checkpt_blocks) * dev->param.chunks_per_block;
368 
369 	return (dev->n_free_chunks > (reserved_chunks + n_chunks));
370 }
371 
yaffs_find_alloc_block(struct yaffs_dev * dev)372 static int yaffs_find_alloc_block(struct yaffs_dev *dev)
373 {
374 	int i;
375 	struct yaffs_block_info *bi;
376 
377 	if (dev->n_erased_blocks < 1) {
378 		/* Hoosterman we've got a problem.
379 		 * Can't get space to gc
380 		 */
381 		yaffs_trace(YAFFS_TRACE_ERROR,
382 		  "yaffs tragedy: no more erased blocks");
383 
384 		return -1;
385 	}
386 
387 	/* Find an empty block. */
388 
389 	for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
390 		dev->alloc_block_finder++;
391 		if (dev->alloc_block_finder < dev->internal_start_block
392 		    || dev->alloc_block_finder > dev->internal_end_block) {
393 			dev->alloc_block_finder = dev->internal_start_block;
394 		}
395 
396 		bi = yaffs_get_block_info(dev, dev->alloc_block_finder);
397 
398 		if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
399 			bi->block_state = YAFFS_BLOCK_STATE_ALLOCATING;
400 			dev->seq_number++;
401 			bi->seq_number = dev->seq_number;
402 			dev->n_erased_blocks--;
403 			yaffs_trace(YAFFS_TRACE_ALLOCATE,
404 			  "Allocated block %d, seq  %d, %d left" ,
405 			   dev->alloc_block_finder, dev->seq_number,
406 			   dev->n_erased_blocks);
407 			return dev->alloc_block_finder;
408 		}
409 	}
410 
411 	yaffs_trace(YAFFS_TRACE_ALWAYS,
412 		"yaffs tragedy: no more erased blocks, but there should have been %d",
413 		dev->n_erased_blocks);
414 
415 	return -1;
416 }
417 
yaffs_alloc_chunk(struct yaffs_dev * dev,int use_reserver,struct yaffs_block_info ** block_ptr)418 static int yaffs_alloc_chunk(struct yaffs_dev *dev, int use_reserver,
419 			     struct yaffs_block_info **block_ptr)
420 {
421 	int ret_val;
422 	struct yaffs_block_info *bi;
423 
424 	if (dev->alloc_block < 0) {
425 		/* Get next block to allocate off */
426 		dev->alloc_block = yaffs_find_alloc_block(dev);
427 		dev->alloc_page = 0;
428 	}
429 
430 	if (!use_reserver && !yaffs_check_alloc_available(dev, 1)) {
431 		/* No space unless we're allowed to use the reserve. */
432 		return -1;
433 	}
434 
435 	if (dev->n_erased_blocks < dev->param.n_reserved_blocks
436 	    && dev->alloc_page == 0)
437 		yaffs_trace(YAFFS_TRACE_ALLOCATE, "Allocating reserve");
438 
439 	/* Next page please.... */
440 	if (dev->alloc_block >= 0) {
441 		bi = yaffs_get_block_info(dev, dev->alloc_block);
442 
443 		ret_val = (dev->alloc_block * dev->param.chunks_per_block) +
444 		    dev->alloc_page;
445 		bi->pages_in_use++;
446 		yaffs_set_chunk_bit(dev, dev->alloc_block, dev->alloc_page);
447 
448 		dev->alloc_page++;
449 
450 		dev->n_free_chunks--;
451 
452 		/* If the block is full set the state to full */
453 		if (dev->alloc_page >= dev->param.chunks_per_block) {
454 			bi->block_state = YAFFS_BLOCK_STATE_FULL;
455 			dev->alloc_block = -1;
456 		}
457 
458 		if (block_ptr)
459 			*block_ptr = bi;
460 
461 		return ret_val;
462 	}
463 
464 	yaffs_trace(YAFFS_TRACE_ERROR,
465 		"!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!");
466 
467 	return -1;
468 }
469 
yaffs_get_erased_chunks(struct yaffs_dev * dev)470 static int yaffs_get_erased_chunks(struct yaffs_dev *dev)
471 {
472 	int n;
473 
474 	n = dev->n_erased_blocks * dev->param.chunks_per_block;
475 
476 	if (dev->alloc_block > 0)
477 		n += (dev->param.chunks_per_block - dev->alloc_page);
478 
479 	return n;
480 
481 }
482 
483 /*
484  * yaffs_skip_rest_of_block() skips over the rest of the allocation block
485  * if we don't want to write to it.
486  */
yaffs_skip_rest_of_block(struct yaffs_dev * dev)487 void yaffs_skip_rest_of_block(struct yaffs_dev *dev)
488 {
489 	struct yaffs_block_info *bi;
490 
491 	if (dev->alloc_block > 0) {
492 		bi = yaffs_get_block_info(dev, dev->alloc_block);
493 		if (bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING) {
494 			bi->block_state = YAFFS_BLOCK_STATE_FULL;
495 			dev->alloc_block = -1;
496 		}
497 	}
498 }
499 
yaffs_write_new_chunk(struct yaffs_dev * dev,const u8 * data,struct yaffs_ext_tags * tags,int use_reserver)500 static int yaffs_write_new_chunk(struct yaffs_dev *dev,
501 				 const u8 *data,
502 				 struct yaffs_ext_tags *tags, int use_reserver)
503 {
504 	int attempts = 0;
505 	int write_ok = 0;
506 	int chunk;
507 
508 	yaffs2_checkpt_invalidate(dev);
509 
510 	do {
511 		struct yaffs_block_info *bi = 0;
512 		int erased_ok = 0;
513 
514 		chunk = yaffs_alloc_chunk(dev, use_reserver, &bi);
515 		if (chunk < 0) {
516 			/* no space */
517 			break;
518 		}
519 
520 		/* First check this chunk is erased, if it needs
521 		 * checking.  The checking policy (unless forced
522 		 * always on) is as follows:
523 		 *
524 		 * Check the first page we try to write in a block.
525 		 * If the check passes then we don't need to check any
526 		 * more.        If the check fails, we check again...
527 		 * If the block has been erased, we don't need to check.
528 		 *
529 		 * However, if the block has been prioritised for gc,
530 		 * then we think there might be something odd about
531 		 * this block and stop using it.
532 		 *
533 		 * Rationale: We should only ever see chunks that have
534 		 * not been erased if there was a partially written
535 		 * chunk due to power loss.  This checking policy should
536 		 * catch that case with very few checks and thus save a
537 		 * lot of checks that are most likely not needed.
538 		 *
539 		 * Mods to the above
540 		 * If an erase check fails or the write fails we skip the
541 		 * rest of the block.
542 		 */
543 
544 		/* let's give it a try */
545 		attempts++;
546 
547 		if (dev->param.always_check_erased)
548 			bi->skip_erased_check = 0;
549 
550 		if (!bi->skip_erased_check) {
551 			erased_ok = yaffs_check_chunk_erased(dev, chunk);
552 			if (erased_ok != YAFFS_OK) {
553 				yaffs_trace(YAFFS_TRACE_ERROR,
554 				  "**>> yaffs chunk %d was not erased",
555 				  chunk);
556 
557 				/* If not erased, delete this one,
558 				 * skip rest of block and
559 				 * try another chunk */
560 				yaffs_chunk_del(dev, chunk, 1, __LINE__);
561 				yaffs_skip_rest_of_block(dev);
562 				continue;
563 			}
564 		}
565 
566 		write_ok = yaffs_wr_chunk_tags_nand(dev, chunk, data, tags);
567 
568 		if (!bi->skip_erased_check)
569 			write_ok =
570 			    yaffs_verify_chunk_written(dev, chunk, data, tags);
571 
572 		if (write_ok != YAFFS_OK) {
573 			/* Clean up aborted write, skip to next block and
574 			 * try another chunk */
575 			yaffs_handle_chunk_wr_error(dev, chunk, erased_ok);
576 			continue;
577 		}
578 
579 		bi->skip_erased_check = 1;
580 
581 		/* Copy the data into the robustification buffer */
582 		yaffs_handle_chunk_wr_ok(dev, chunk, data, tags);
583 
584 	} while (write_ok != YAFFS_OK &&
585 		 (yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
586 
587 	if (!write_ok)
588 		chunk = -1;
589 
590 	if (attempts > 1) {
591 		yaffs_trace(YAFFS_TRACE_ERROR,
592 			"**>> yaffs write required %d attempts",
593 			attempts);
594 		dev->n_retried_writes += (attempts - 1);
595 	}
596 
597 	return chunk;
598 }
599 
600 /*
601  * Block retiring for handling a broken block.
602  */
603 
yaffs_retire_block(struct yaffs_dev * dev,int flash_block)604 static void yaffs_retire_block(struct yaffs_dev *dev, int flash_block)
605 {
606 	struct yaffs_block_info *bi = yaffs_get_block_info(dev, flash_block);
607 
608 	yaffs2_checkpt_invalidate(dev);
609 
610 	yaffs2_clear_oldest_dirty_seq(dev, bi);
611 
612 	if (yaffs_mark_bad(dev, flash_block) != YAFFS_OK) {
613 		if (yaffs_erase_block(dev, flash_block) != YAFFS_OK) {
614 			yaffs_trace(YAFFS_TRACE_ALWAYS,
615 				"yaffs: Failed to mark bad and erase block %d",
616 				flash_block);
617 		} else {
618 			struct yaffs_ext_tags tags;
619 			int chunk_id =
620 			    flash_block * dev->param.chunks_per_block;
621 
622 			u8 *buffer = yaffs_get_temp_buffer(dev);
623 
624 			memset(buffer, 0xff, dev->data_bytes_per_chunk);
625 			memset(&tags, 0, sizeof(tags));
626 			tags.seq_number = YAFFS_SEQUENCE_BAD_BLOCK;
627 			if (dev->param.write_chunk_tags_fn(dev, chunk_id -
628 							   dev->chunk_offset,
629 							   buffer,
630 							   &tags) != YAFFS_OK)
631 				yaffs_trace(YAFFS_TRACE_ALWAYS,
632 					"yaffs: Failed to write bad block marker to block %d",
633 					flash_block);
634 
635 			yaffs_release_temp_buffer(dev, buffer);
636 		}
637 	}
638 
639 	bi->block_state = YAFFS_BLOCK_STATE_DEAD;
640 	bi->gc_prioritise = 0;
641 	bi->needs_retiring = 0;
642 
643 	dev->n_retired_blocks++;
644 }
645 
646 /*---------------- Name handling functions ------------*/
647 
yaffs_calc_name_sum(const YCHAR * name)648 static u16 yaffs_calc_name_sum(const YCHAR *name)
649 {
650 	u16 sum = 0;
651 	u16 i = 1;
652 
653 	if (!name)
654 		return 0;
655 
656 	while ((*name) && i < (YAFFS_MAX_NAME_LENGTH / 2)) {
657 
658 		/* 0x1f mask is case insensitive */
659 		sum += ((*name) & 0x1f) * i;
660 		i++;
661 		name++;
662 	}
663 	return sum;
664 }
665 
yaffs_set_obj_name(struct yaffs_obj * obj,const YCHAR * name)666 void yaffs_set_obj_name(struct yaffs_obj *obj, const YCHAR * name)
667 {
668 	memset(obj->short_name, 0, sizeof(obj->short_name));
669 	if (name &&
670 		yaffs_strnlen(name, YAFFS_SHORT_NAME_LENGTH + 1) <=
671 		YAFFS_SHORT_NAME_LENGTH)
672 		yaffs_strcpy(obj->short_name, name);
673 	else
674 		obj->short_name[0] = _Y('\0');
675 	obj->sum = yaffs_calc_name_sum(name);
676 }
677 
yaffs_set_obj_name_from_oh(struct yaffs_obj * obj,const struct yaffs_obj_hdr * oh)678 void yaffs_set_obj_name_from_oh(struct yaffs_obj *obj,
679 				const struct yaffs_obj_hdr *oh)
680 {
681 #ifdef CONFIG_YAFFS_AUTO_UNICODE
682 	YCHAR tmp_name[YAFFS_MAX_NAME_LENGTH + 1];
683 	memset(tmp_name, 0, sizeof(tmp_name));
684 	yaffs_load_name_from_oh(obj->my_dev, tmp_name, oh->name,
685 				YAFFS_MAX_NAME_LENGTH + 1);
686 	yaffs_set_obj_name(obj, tmp_name);
687 #else
688 	yaffs_set_obj_name(obj, oh->name);
689 #endif
690 }
691 
yaffs_max_file_size(struct yaffs_dev * dev)692 loff_t yaffs_max_file_size(struct yaffs_dev *dev)
693 {
694 	return ((loff_t) YAFFS_MAX_CHUNK_ID) * dev->data_bytes_per_chunk;
695 }
696 
697 /*-------------------- TNODES -------------------
698 
699  * List of spare tnodes
700  * The list is hooked together using the first pointer
701  * in the tnode.
702  */
703 
yaffs_get_tnode(struct yaffs_dev * dev)704 struct yaffs_tnode *yaffs_get_tnode(struct yaffs_dev *dev)
705 {
706 	struct yaffs_tnode *tn = yaffs_alloc_raw_tnode(dev);
707 
708 	if (tn) {
709 		memset(tn, 0, dev->tnode_size);
710 		dev->n_tnodes++;
711 	}
712 
713 	dev->checkpoint_blocks_required = 0;	/* force recalculation */
714 
715 	return tn;
716 }
717 
718 /* FreeTnode frees up a tnode and puts it back on the free list */
yaffs_free_tnode(struct yaffs_dev * dev,struct yaffs_tnode * tn)719 static void yaffs_free_tnode(struct yaffs_dev *dev, struct yaffs_tnode *tn)
720 {
721 	yaffs_free_raw_tnode(dev, tn);
722 	dev->n_tnodes--;
723 	dev->checkpoint_blocks_required = 0;	/* force recalculation */
724 }
725 
yaffs_deinit_tnodes_and_objs(struct yaffs_dev * dev)726 static void yaffs_deinit_tnodes_and_objs(struct yaffs_dev *dev)
727 {
728 	yaffs_deinit_raw_tnodes_and_objs(dev);
729 	dev->n_obj = 0;
730 	dev->n_tnodes = 0;
731 }
732 
yaffs_load_tnode_0(struct yaffs_dev * dev,struct yaffs_tnode * tn,unsigned pos,unsigned val)733 void yaffs_load_tnode_0(struct yaffs_dev *dev, struct yaffs_tnode *tn,
734 			unsigned pos, unsigned val)
735 {
736 	u32 *map = (u32 *) tn;
737 	u32 bit_in_map;
738 	u32 bit_in_word;
739 	u32 word_in_map;
740 	u32 mask;
741 
742 	pos &= YAFFS_TNODES_LEVEL0_MASK;
743 	val >>= dev->chunk_grp_bits;
744 
745 	bit_in_map = pos * dev->tnode_width;
746 	word_in_map = bit_in_map / 32;
747 	bit_in_word = bit_in_map & (32 - 1);
748 
749 	mask = dev->tnode_mask << bit_in_word;
750 
751 	map[word_in_map] &= ~mask;
752 	map[word_in_map] |= (mask & (val << bit_in_word));
753 
754 	if (dev->tnode_width > (32 - bit_in_word)) {
755 		bit_in_word = (32 - bit_in_word);
756 		word_in_map++;
757 		mask =
758 		    dev->tnode_mask >> bit_in_word;
759 		map[word_in_map] &= ~mask;
760 		map[word_in_map] |= (mask & (val >> bit_in_word));
761 	}
762 }
763 
yaffs_get_group_base(struct yaffs_dev * dev,struct yaffs_tnode * tn,unsigned pos)764 u32 yaffs_get_group_base(struct yaffs_dev *dev, struct yaffs_tnode *tn,
765 			 unsigned pos)
766 {
767 	u32 *map = (u32 *) tn;
768 	u32 bit_in_map;
769 	u32 bit_in_word;
770 	u32 word_in_map;
771 	u32 val;
772 
773 	pos &= YAFFS_TNODES_LEVEL0_MASK;
774 
775 	bit_in_map = pos * dev->tnode_width;
776 	word_in_map = bit_in_map / 32;
777 	bit_in_word = bit_in_map & (32 - 1);
778 
779 	val = map[word_in_map] >> bit_in_word;
780 
781 	if (dev->tnode_width > (32 - bit_in_word)) {
782 		bit_in_word = (32 - bit_in_word);
783 		word_in_map++;
784 		val |= (map[word_in_map] << bit_in_word);
785 	}
786 
787 	val &= dev->tnode_mask;
788 	val <<= dev->chunk_grp_bits;
789 
790 	return val;
791 }
792 
793 /* ------------------- End of individual tnode manipulation -----------------*/
794 
795 /* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
796  * The look up tree is represented by the top tnode and the number of top_level
797  * in the tree. 0 means only the level 0 tnode is in the tree.
798  */
799 
800 /* FindLevel0Tnode finds the level 0 tnode, if one exists. */
yaffs_find_tnode_0(struct yaffs_dev * dev,struct yaffs_file_var * file_struct,u32 chunk_id)801 struct yaffs_tnode *yaffs_find_tnode_0(struct yaffs_dev *dev,
802 				       struct yaffs_file_var *file_struct,
803 				       u32 chunk_id)
804 {
805 	struct yaffs_tnode *tn = file_struct->top;
806 	u32 i;
807 	int required_depth;
808 	int level = file_struct->top_level;
809 
810 	/* Check sane level and chunk Id */
811 	if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL)
812 		return NULL;
813 
814 	if (chunk_id > YAFFS_MAX_CHUNK_ID)
815 		return NULL;
816 
817 	/* First check we're tall enough (ie enough top_level) */
818 
819 	i = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
820 	required_depth = 0;
821 	while (i) {
822 		i >>= YAFFS_TNODES_INTERNAL_BITS;
823 		required_depth++;
824 	}
825 
826 	if (required_depth > file_struct->top_level)
827 		return NULL;	/* Not tall enough, so we can't find it */
828 
829 	/* Traverse down to level 0 */
830 	while (level > 0 && tn) {
831 		tn = tn->internal[(chunk_id >>
832 				   (YAFFS_TNODES_LEVEL0_BITS +
833 				    (level - 1) *
834 				    YAFFS_TNODES_INTERNAL_BITS)) &
835 				  YAFFS_TNODES_INTERNAL_MASK];
836 		level--;
837 	}
838 
839 	return tn;
840 }
841 
842 /* add_find_tnode_0 finds the level 0 tnode if it exists,
843  * otherwise first expands the tree.
844  * This happens in two steps:
845  *  1. If the tree isn't tall enough, then make it taller.
846  *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
847  *
848  * Used when modifying the tree.
849  *
850  *  If the tn argument is NULL, then a fresh tnode will be added otherwise the
851  *  specified tn will be plugged into the ttree.
852  */
853 
yaffs_add_find_tnode_0(struct yaffs_dev * dev,struct yaffs_file_var * file_struct,u32 chunk_id,struct yaffs_tnode * passed_tn)854 struct yaffs_tnode *yaffs_add_find_tnode_0(struct yaffs_dev *dev,
855 					   struct yaffs_file_var *file_struct,
856 					   u32 chunk_id,
857 					   struct yaffs_tnode *passed_tn)
858 {
859 	int required_depth;
860 	int i;
861 	int l;
862 	struct yaffs_tnode *tn;
863 	u32 x;
864 
865 	/* Check sane level and page Id */
866 	if (file_struct->top_level < 0 ||
867 	    file_struct->top_level > YAFFS_TNODES_MAX_LEVEL)
868 		return NULL;
869 
870 	if (chunk_id > YAFFS_MAX_CHUNK_ID)
871 		return NULL;
872 
873 	/* First check we're tall enough (ie enough top_level) */
874 
875 	x = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
876 	required_depth = 0;
877 	while (x) {
878 		x >>= YAFFS_TNODES_INTERNAL_BITS;
879 		required_depth++;
880 	}
881 
882 	if (required_depth > file_struct->top_level) {
883 		/* Not tall enough, gotta make the tree taller */
884 		for (i = file_struct->top_level; i < required_depth; i++) {
885 
886 			tn = yaffs_get_tnode(dev);
887 
888 			if (tn) {
889 				tn->internal[0] = file_struct->top;
890 				file_struct->top = tn;
891 				file_struct->top_level++;
892 			} else {
893 				yaffs_trace(YAFFS_TRACE_ERROR,
894 					"yaffs: no more tnodes");
895 				return NULL;
896 			}
897 		}
898 	}
899 
900 	/* Traverse down to level 0, adding anything we need */
901 
902 	l = file_struct->top_level;
903 	tn = file_struct->top;
904 
905 	if (l > 0) {
906 		while (l > 0 && tn) {
907 			x = (chunk_id >>
908 			     (YAFFS_TNODES_LEVEL0_BITS +
909 			      (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
910 			    YAFFS_TNODES_INTERNAL_MASK;
911 
912 			if ((l > 1) && !tn->internal[x]) {
913 				/* Add missing non-level-zero tnode */
914 				tn->internal[x] = yaffs_get_tnode(dev);
915 				if (!tn->internal[x])
916 					return NULL;
917 			} else if (l == 1) {
918 				/* Looking from level 1 at level 0 */
919 				if (passed_tn) {
920 					/* If we already have one, release it */
921 					if (tn->internal[x])
922 						yaffs_free_tnode(dev,
923 							tn->internal[x]);
924 					tn->internal[x] = passed_tn;
925 
926 				} else if (!tn->internal[x]) {
927 					/* Don't have one, none passed in */
928 					tn->internal[x] = yaffs_get_tnode(dev);
929 					if (!tn->internal[x])
930 						return NULL;
931 				}
932 			}
933 
934 			tn = tn->internal[x];
935 			l--;
936 		}
937 	} else {
938 		/* top is level 0 */
939 		if (passed_tn) {
940 			memcpy(tn, passed_tn,
941 			       (dev->tnode_width * YAFFS_NTNODES_LEVEL0) / 8);
942 			yaffs_free_tnode(dev, passed_tn);
943 		}
944 	}
945 
946 	return tn;
947 }
948 
yaffs_tags_match(const struct yaffs_ext_tags * tags,int obj_id,int chunk_obj)949 static int yaffs_tags_match(const struct yaffs_ext_tags *tags, int obj_id,
950 			    int chunk_obj)
951 {
952 	return (tags->chunk_id == chunk_obj &&
953 		tags->obj_id == obj_id &&
954 		!tags->is_deleted) ? 1 : 0;
955 
956 }
957 
yaffs_find_chunk_in_group(struct yaffs_dev * dev,int the_chunk,struct yaffs_ext_tags * tags,int obj_id,int inode_chunk)958 static int yaffs_find_chunk_in_group(struct yaffs_dev *dev, int the_chunk,
959 					struct yaffs_ext_tags *tags, int obj_id,
960 					int inode_chunk)
961 {
962 	int j;
963 
964 	for (j = 0; the_chunk && j < dev->chunk_grp_size; j++) {
965 		if (yaffs_check_chunk_bit
966 		    (dev, the_chunk / dev->param.chunks_per_block,
967 		     the_chunk % dev->param.chunks_per_block)) {
968 
969 			if (dev->chunk_grp_size == 1)
970 				return the_chunk;
971 			else {
972 				yaffs_rd_chunk_tags_nand(dev, the_chunk, NULL,
973 							 tags);
974 				if (yaffs_tags_match(tags,
975 							obj_id, inode_chunk)) {
976 					/* found it; */
977 					return the_chunk;
978 				}
979 			}
980 		}
981 		the_chunk++;
982 	}
983 	return -1;
984 }
985 
yaffs_find_chunk_in_file(struct yaffs_obj * in,int inode_chunk,struct yaffs_ext_tags * tags)986 static int yaffs_find_chunk_in_file(struct yaffs_obj *in, int inode_chunk,
987 				    struct yaffs_ext_tags *tags)
988 {
989 	/*Get the Tnode, then get the level 0 offset chunk offset */
990 	struct yaffs_tnode *tn;
991 	int the_chunk = -1;
992 	struct yaffs_ext_tags local_tags;
993 	int ret_val = -1;
994 	struct yaffs_dev *dev = in->my_dev;
995 
996 	if (!tags) {
997 		/* Passed a NULL, so use our own tags space */
998 		tags = &local_tags;
999 	}
1000 
1001 	tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
1002 
1003 	if (!tn)
1004 		return ret_val;
1005 
1006 	the_chunk = yaffs_get_group_base(dev, tn, inode_chunk);
1007 
1008 	ret_val = yaffs_find_chunk_in_group(dev, the_chunk, tags, in->obj_id,
1009 					      inode_chunk);
1010 	return ret_val;
1011 }
1012 
yaffs_find_del_file_chunk(struct yaffs_obj * in,int inode_chunk,struct yaffs_ext_tags * tags)1013 static int yaffs_find_del_file_chunk(struct yaffs_obj *in, int inode_chunk,
1014 				     struct yaffs_ext_tags *tags)
1015 {
1016 	/* Get the Tnode, then get the level 0 offset chunk offset */
1017 	struct yaffs_tnode *tn;
1018 	int the_chunk = -1;
1019 	struct yaffs_ext_tags local_tags;
1020 	struct yaffs_dev *dev = in->my_dev;
1021 	int ret_val = -1;
1022 
1023 	if (!tags) {
1024 		/* Passed a NULL, so use our own tags space */
1025 		tags = &local_tags;
1026 	}
1027 
1028 	tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
1029 
1030 	if (!tn)
1031 		return ret_val;
1032 
1033 	the_chunk = yaffs_get_group_base(dev, tn, inode_chunk);
1034 
1035 	ret_val = yaffs_find_chunk_in_group(dev, the_chunk, tags, in->obj_id,
1036 					      inode_chunk);
1037 
1038 	/* Delete the entry in the filestructure (if found) */
1039 	if (ret_val != -1)
1040 		yaffs_load_tnode_0(dev, tn, inode_chunk, 0);
1041 
1042 	return ret_val;
1043 }
1044 
yaffs_put_chunk_in_file(struct yaffs_obj * in,int inode_chunk,int nand_chunk,int in_scan)1045 int yaffs_put_chunk_in_file(struct yaffs_obj *in, int inode_chunk,
1046 			    int nand_chunk, int in_scan)
1047 {
1048 	/* NB in_scan is zero unless scanning.
1049 	 * For forward scanning, in_scan is > 0;
1050 	 * for backward scanning in_scan is < 0
1051 	 *
1052 	 * nand_chunk = 0 is a dummy insert to make sure the tnodes are there.
1053 	 */
1054 
1055 	struct yaffs_tnode *tn;
1056 	struct yaffs_dev *dev = in->my_dev;
1057 	int existing_cunk;
1058 	struct yaffs_ext_tags existing_tags;
1059 	struct yaffs_ext_tags new_tags;
1060 	unsigned existing_serial, new_serial;
1061 
1062 	if (in->variant_type != YAFFS_OBJECT_TYPE_FILE) {
1063 		/* Just ignore an attempt at putting a chunk into a non-file
1064 		 * during scanning.
1065 		 * If it is not during Scanning then something went wrong!
1066 		 */
1067 		if (!in_scan) {
1068 			yaffs_trace(YAFFS_TRACE_ERROR,
1069 				"yaffs tragedy:attempt to put data chunk into a non-file"
1070 				);
1071 			BUG();
1072 		}
1073 
1074 		yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
1075 		return YAFFS_OK;
1076 	}
1077 
1078 	tn = yaffs_add_find_tnode_0(dev,
1079 				    &in->variant.file_variant,
1080 				    inode_chunk, NULL);
1081 	if (!tn)
1082 		return YAFFS_FAIL;
1083 
1084 	if (!nand_chunk)
1085 		/* Dummy insert, bail now */
1086 		return YAFFS_OK;
1087 
1088 	existing_cunk = yaffs_get_group_base(dev, tn, inode_chunk);
1089 
1090 	if (in_scan != 0) {
1091 		/* If we're scanning then we need to test for duplicates
1092 		 * NB This does not need to be efficient since it should only
1093 		 * happen when the power fails during a write, then only one
1094 		 * chunk should ever be affected.
1095 		 *
1096 		 * Correction for YAFFS2: This could happen quite a lot and we
1097 		 * need to think about efficiency! TODO
1098 		 * Update: For backward scanning we don't need to re-read tags
1099 		 * so this is quite cheap.
1100 		 */
1101 
1102 		if (existing_cunk > 0) {
1103 			/* NB Right now existing chunk will not be real
1104 			 * chunk_id if the chunk group size > 1
1105 			 * thus we have to do a FindChunkInFile to get the
1106 			 * real chunk id.
1107 			 *
1108 			 * We have a duplicate now we need to decide which
1109 			 * one to use:
1110 			 *
1111 			 * Backwards scanning YAFFS2: The old one is what
1112 			 * we use, dump the new one.
1113 			 * YAFFS1: Get both sets of tags and compare serial
1114 			 * numbers.
1115 			 */
1116 
1117 			if (in_scan > 0) {
1118 				/* Only do this for forward scanning */
1119 				yaffs_rd_chunk_tags_nand(dev,
1120 							 nand_chunk,
1121 							 NULL, &new_tags);
1122 
1123 				/* Do a proper find */
1124 				existing_cunk =
1125 				    yaffs_find_chunk_in_file(in, inode_chunk,
1126 							     &existing_tags);
1127 			}
1128 
1129 			if (existing_cunk <= 0) {
1130 				/*Hoosterman - how did this happen? */
1131 
1132 				yaffs_trace(YAFFS_TRACE_ERROR,
1133 					"yaffs tragedy: existing chunk < 0 in scan"
1134 					);
1135 
1136 			}
1137 
1138 			/* NB The deleted flags should be false, otherwise
1139 			 * the chunks will not be loaded during a scan
1140 			 */
1141 
1142 			if (in_scan > 0) {
1143 				new_serial = new_tags.serial_number;
1144 				existing_serial = existing_tags.serial_number;
1145 			}
1146 
1147 			if ((in_scan > 0) &&
1148 			    (existing_cunk <= 0 ||
1149 			     ((existing_serial + 1) & 3) == new_serial)) {
1150 				/* Forward scanning.
1151 				 * Use new
1152 				 * Delete the old one and drop through to
1153 				 * update the tnode
1154 				 */
1155 				yaffs_chunk_del(dev, existing_cunk, 1,
1156 						__LINE__);
1157 			} else {
1158 				/* Backward scanning or we want to use the
1159 				 * existing one
1160 				 * Delete the new one and return early so that
1161 				 * the tnode isn't changed
1162 				 */
1163 				yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
1164 				return YAFFS_OK;
1165 			}
1166 		}
1167 
1168 	}
1169 
1170 	if (existing_cunk == 0)
1171 		in->n_data_chunks++;
1172 
1173 	yaffs_load_tnode_0(dev, tn, inode_chunk, nand_chunk);
1174 
1175 	return YAFFS_OK;
1176 }
1177 
yaffs_soft_del_chunk(struct yaffs_dev * dev,int chunk)1178 static void yaffs_soft_del_chunk(struct yaffs_dev *dev, int chunk)
1179 {
1180 	struct yaffs_block_info *the_block;
1181 	unsigned block_no;
1182 
1183 	yaffs_trace(YAFFS_TRACE_DELETION, "soft delete chunk %d", chunk);
1184 
1185 	block_no = chunk / dev->param.chunks_per_block;
1186 	the_block = yaffs_get_block_info(dev, block_no);
1187 	if (the_block) {
1188 		the_block->soft_del_pages++;
1189 		dev->n_free_chunks++;
1190 		yaffs2_update_oldest_dirty_seq(dev, block_no, the_block);
1191 	}
1192 }
1193 
1194 /* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all
1195  * the chunks in the file.
1196  * All soft deleting does is increment the block's softdelete count and pulls
1197  * the chunk out of the tnode.
1198  * Thus, essentially this is the same as DeleteWorker except that the chunks
1199  * are soft deleted.
1200  */
1201 
yaffs_soft_del_worker(struct yaffs_obj * in,struct yaffs_tnode * tn,u32 level,int chunk_offset)1202 static int yaffs_soft_del_worker(struct yaffs_obj *in, struct yaffs_tnode *tn,
1203 				 u32 level, int chunk_offset)
1204 {
1205 	int i;
1206 	int the_chunk;
1207 	int all_done = 1;
1208 	struct yaffs_dev *dev = in->my_dev;
1209 
1210 	if (!tn)
1211 		return 1;
1212 
1213 	if (level > 0) {
1214 		for (i = YAFFS_NTNODES_INTERNAL - 1;
1215 			all_done && i >= 0;
1216 			i--) {
1217 			if (tn->internal[i]) {
1218 				all_done =
1219 				    yaffs_soft_del_worker(in,
1220 					tn->internal[i],
1221 					level - 1,
1222 					(chunk_offset <<
1223 					YAFFS_TNODES_INTERNAL_BITS)
1224 					+ i);
1225 				if (all_done) {
1226 					yaffs_free_tnode(dev,
1227 						tn->internal[i]);
1228 					tn->internal[i] = NULL;
1229 				} else {
1230 					/* Can this happen? */
1231 				}
1232 			}
1233 		}
1234 		return (all_done) ? 1 : 0;
1235 	}
1236 
1237 	/* level 0 */
1238 	 for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
1239 		the_chunk = yaffs_get_group_base(dev, tn, i);
1240 		if (the_chunk) {
1241 			yaffs_soft_del_chunk(dev, the_chunk);
1242 			yaffs_load_tnode_0(dev, tn, i, 0);
1243 		}
1244 	}
1245 	return 1;
1246 }
1247 
yaffs_remove_obj_from_dir(struct yaffs_obj * obj)1248 static void yaffs_remove_obj_from_dir(struct yaffs_obj *obj)
1249 {
1250 	struct yaffs_dev *dev = obj->my_dev;
1251 	struct yaffs_obj *parent;
1252 
1253 	yaffs_verify_obj_in_dir(obj);
1254 	parent = obj->parent;
1255 
1256 	yaffs_verify_dir(parent);
1257 
1258 	if (dev && dev->param.remove_obj_fn)
1259 		dev->param.remove_obj_fn(obj);
1260 
1261 	list_del_init(&obj->siblings);
1262 	obj->parent = NULL;
1263 
1264 	yaffs_verify_dir(parent);
1265 }
1266 
yaffs_add_obj_to_dir(struct yaffs_obj * directory,struct yaffs_obj * obj)1267 void yaffs_add_obj_to_dir(struct yaffs_obj *directory, struct yaffs_obj *obj)
1268 {
1269 	if (!directory) {
1270 		yaffs_trace(YAFFS_TRACE_ALWAYS,
1271 			"tragedy: Trying to add an object to a null pointer directory"
1272 			);
1273 		BUG();
1274 		return;
1275 	}
1276 	if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
1277 		yaffs_trace(YAFFS_TRACE_ALWAYS,
1278 			"tragedy: Trying to add an object to a non-directory"
1279 			);
1280 		BUG();
1281 	}
1282 
1283 	if (obj->siblings.prev == NULL) {
1284 		/* Not initialised */
1285 		BUG();
1286 	}
1287 
1288 	yaffs_verify_dir(directory);
1289 
1290 	yaffs_remove_obj_from_dir(obj);
1291 
1292 	/* Now add it */
1293 	list_add(&obj->siblings, &directory->variant.dir_variant.children);
1294 	obj->parent = directory;
1295 
1296 	if (directory == obj->my_dev->unlinked_dir
1297 	    || directory == obj->my_dev->del_dir) {
1298 		obj->unlinked = 1;
1299 		obj->my_dev->n_unlinked_files++;
1300 		obj->rename_allowed = 0;
1301 	}
1302 
1303 	yaffs_verify_dir(directory);
1304 	yaffs_verify_obj_in_dir(obj);
1305 }
1306 
yaffs_change_obj_name(struct yaffs_obj * obj,struct yaffs_obj * new_dir,const YCHAR * new_name,int force,int shadows)1307 static int yaffs_change_obj_name(struct yaffs_obj *obj,
1308 				 struct yaffs_obj *new_dir,
1309 				 const YCHAR *new_name, int force, int shadows)
1310 {
1311 	int unlink_op;
1312 	int del_op;
1313 	struct yaffs_obj *existing_target;
1314 
1315 	if (new_dir == NULL)
1316 		new_dir = obj->parent;	/* use the old directory */
1317 
1318 	if (new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
1319 		yaffs_trace(YAFFS_TRACE_ALWAYS,
1320 			"tragedy: yaffs_change_obj_name: new_dir is not a directory"
1321 			);
1322 		BUG();
1323 	}
1324 
1325 	unlink_op = (new_dir == obj->my_dev->unlinked_dir);
1326 	del_op = (new_dir == obj->my_dev->del_dir);
1327 
1328 	existing_target = yaffs_find_by_name(new_dir, new_name);
1329 
1330 	/* If the object is a file going into the unlinked directory,
1331 	 *   then it is OK to just stuff it in since duplicate names are OK.
1332 	 *   else only proceed if the new name does not exist and we're putting
1333 	 *   it into a directory.
1334 	 */
1335 	if (!(unlink_op || del_op || force ||
1336 	      shadows > 0 || !existing_target) ||
1337 	      new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
1338 		return YAFFS_FAIL;
1339 
1340 	yaffs_set_obj_name(obj, new_name);
1341 	obj->dirty = 1;
1342 	yaffs_add_obj_to_dir(new_dir, obj);
1343 
1344 	if (unlink_op)
1345 		obj->unlinked = 1;
1346 
1347 	/* If it is a deletion then we mark it as a shrink for gc  */
1348 	if (yaffs_update_oh(obj, new_name, 0, del_op, shadows, NULL) >= 0)
1349 		return YAFFS_OK;
1350 
1351 	return YAFFS_FAIL;
1352 }
1353 
1354 /*------------------------ Short Operations Cache ------------------------------
1355  *   In many situations where there is no high level buffering  a lot of
1356  *   reads might be short sequential reads, and a lot of writes may be short
1357  *   sequential writes. eg. scanning/writing a jpeg file.
1358  *   In these cases, a short read/write cache can provide a huge perfomance
1359  *   benefit with dumb-as-a-rock code.
1360  *   In Linux, the page cache provides read buffering and the short op cache
1361  *   provides write buffering.
1362  *
1363  *   There are a small number (~10) of cache chunks per device so that we don't
1364  *   need a very intelligent search.
1365  */
1366 
yaffs_obj_cache_dirty(struct yaffs_obj * obj)1367 static int yaffs_obj_cache_dirty(struct yaffs_obj *obj)
1368 {
1369 	struct yaffs_dev *dev = obj->my_dev;
1370 	int i;
1371 	struct yaffs_cache *cache;
1372 	int n_caches = obj->my_dev->param.n_caches;
1373 
1374 	for (i = 0; i < n_caches; i++) {
1375 		cache = &dev->cache[i];
1376 		if (cache->object == obj && cache->dirty)
1377 			return 1;
1378 	}
1379 
1380 	return 0;
1381 }
1382 
yaffs_flush_file_cache(struct yaffs_obj * obj)1383 static void yaffs_flush_file_cache(struct yaffs_obj *obj)
1384 {
1385 	struct yaffs_dev *dev = obj->my_dev;
1386 	int lowest = -99;	/* Stop compiler whining. */
1387 	int i;
1388 	struct yaffs_cache *cache;
1389 	int chunk_written = 0;
1390 	int n_caches = obj->my_dev->param.n_caches;
1391 
1392 	if (n_caches < 1)
1393 		return;
1394 	do {
1395 		cache = NULL;
1396 
1397 		/* Find the lowest dirty chunk for this object */
1398 		for (i = 0; i < n_caches; i++) {
1399 			if (dev->cache[i].object == obj &&
1400 			    dev->cache[i].dirty) {
1401 				if (!cache ||
1402 				    dev->cache[i].chunk_id < lowest) {
1403 					cache = &dev->cache[i];
1404 					lowest = cache->chunk_id;
1405 				}
1406 			}
1407 		}
1408 
1409 		if (cache && !cache->locked) {
1410 			/* Write it out and free it up */
1411 			chunk_written =
1412 			    yaffs_wr_data_obj(cache->object,
1413 					      cache->chunk_id,
1414 					      cache->data,
1415 					      cache->n_bytes, 1);
1416 			cache->dirty = 0;
1417 			cache->object = NULL;
1418 		}
1419 	} while (cache && chunk_written > 0);
1420 
1421 	if (cache)
1422 		/* Hoosterman, disk full while writing cache out. */
1423 		yaffs_trace(YAFFS_TRACE_ERROR,
1424 			"yaffs tragedy: no space during cache write");
1425 }
1426 
1427 /*yaffs_flush_whole_cache(dev)
1428  *
1429  *
1430  */
1431 
yaffs_flush_whole_cache(struct yaffs_dev * dev)1432 void yaffs_flush_whole_cache(struct yaffs_dev *dev)
1433 {
1434 	struct yaffs_obj *obj;
1435 	int n_caches = dev->param.n_caches;
1436 	int i;
1437 
1438 	/* Find a dirty object in the cache and flush it...
1439 	 * until there are no further dirty objects.
1440 	 */
1441 	do {
1442 		obj = NULL;
1443 		for (i = 0; i < n_caches && !obj; i++) {
1444 			if (dev->cache[i].object && dev->cache[i].dirty)
1445 				obj = dev->cache[i].object;
1446 		}
1447 		if (obj)
1448 			yaffs_flush_file_cache(obj);
1449 	} while (obj);
1450 
1451 }
1452 
1453 /* Grab us a cache chunk for use.
1454  * First look for an empty one.
1455  * Then look for the least recently used non-dirty one.
1456  * Then look for the least recently used dirty one...., flush and look again.
1457  */
yaffs_grab_chunk_worker(struct yaffs_dev * dev)1458 static struct yaffs_cache *yaffs_grab_chunk_worker(struct yaffs_dev *dev)
1459 {
1460 	int i;
1461 
1462 	if (dev->param.n_caches > 0) {
1463 		for (i = 0; i < dev->param.n_caches; i++) {
1464 			if (!dev->cache[i].object)
1465 				return &dev->cache[i];
1466 		}
1467 	}
1468 	return NULL;
1469 }
1470 
yaffs_grab_chunk_cache(struct yaffs_dev * dev)1471 static struct yaffs_cache *yaffs_grab_chunk_cache(struct yaffs_dev *dev)
1472 {
1473 	struct yaffs_cache *cache;
1474 	struct yaffs_obj *the_obj;
1475 	int usage;
1476 	int i;
1477 
1478 	if (dev->param.n_caches < 1)
1479 		return NULL;
1480 
1481 	/* Try find a non-dirty one... */
1482 
1483 	cache = yaffs_grab_chunk_worker(dev);
1484 
1485 	if (!cache) {
1486 		/* They were all dirty, find the LRU object and flush
1487 		 * its cache, then  find again.
1488 		 * NB what's here is not very accurate,
1489 		 * we actually flush the object with the LRU chunk.
1490 		 */
1491 
1492 		/* With locking we can't assume we can use entry zero,
1493 		 * Set the_obj to a valid pointer for Coverity. */
1494 		the_obj = dev->cache[0].object;
1495 		usage = -1;
1496 		cache = NULL;
1497 
1498 		for (i = 0; i < dev->param.n_caches; i++) {
1499 			if (dev->cache[i].object &&
1500 			    !dev->cache[i].locked &&
1501 			    (dev->cache[i].last_use < usage ||
1502 			    !cache)) {
1503 				usage = dev->cache[i].last_use;
1504 				the_obj = dev->cache[i].object;
1505 				cache = &dev->cache[i];
1506 			}
1507 		}
1508 
1509 		if (!cache || cache->dirty) {
1510 			/* Flush and try again */
1511 			yaffs_flush_file_cache(the_obj);
1512 			cache = yaffs_grab_chunk_worker(dev);
1513 		}
1514 	}
1515 	return cache;
1516 }
1517 
1518 /* Find a cached chunk */
yaffs_find_chunk_cache(const struct yaffs_obj * obj,int chunk_id)1519 static struct yaffs_cache *yaffs_find_chunk_cache(const struct yaffs_obj *obj,
1520 						  int chunk_id)
1521 {
1522 	struct yaffs_dev *dev = obj->my_dev;
1523 	int i;
1524 
1525 	if (dev->param.n_caches < 1)
1526 		return NULL;
1527 
1528 	for (i = 0; i < dev->param.n_caches; i++) {
1529 		if (dev->cache[i].object == obj &&
1530 		    dev->cache[i].chunk_id == chunk_id) {
1531 			dev->cache_hits++;
1532 
1533 			return &dev->cache[i];
1534 		}
1535 	}
1536 	return NULL;
1537 }
1538 
1539 /* Mark the chunk for the least recently used algorithym */
yaffs_use_cache(struct yaffs_dev * dev,struct yaffs_cache * cache,int is_write)1540 static void yaffs_use_cache(struct yaffs_dev *dev, struct yaffs_cache *cache,
1541 			    int is_write)
1542 {
1543 	int i;
1544 
1545 	if (dev->param.n_caches < 1)
1546 		return;
1547 
1548 	if (dev->cache_last_use < 0 ||
1549 		dev->cache_last_use > 100000000) {
1550 		/* Reset the cache usages */
1551 		for (i = 1; i < dev->param.n_caches; i++)
1552 			dev->cache[i].last_use = 0;
1553 
1554 		dev->cache_last_use = 0;
1555 	}
1556 	dev->cache_last_use++;
1557 	cache->last_use = dev->cache_last_use;
1558 
1559 	if (is_write)
1560 		cache->dirty = 1;
1561 }
1562 
1563 /* Invalidate a single cache page.
1564  * Do this when a whole page gets written,
1565  * ie the short cache for this page is no longer valid.
1566  */
yaffs_invalidate_chunk_cache(struct yaffs_obj * object,int chunk_id)1567 static void yaffs_invalidate_chunk_cache(struct yaffs_obj *object, int chunk_id)
1568 {
1569 	struct yaffs_cache *cache;
1570 
1571 	if (object->my_dev->param.n_caches > 0) {
1572 		cache = yaffs_find_chunk_cache(object, chunk_id);
1573 
1574 		if (cache)
1575 			cache->object = NULL;
1576 	}
1577 }
1578 
1579 /* Invalidate all the cache pages associated with this object
1580  * Do this whenever ther file is deleted or resized.
1581  */
yaffs_invalidate_whole_cache(struct yaffs_obj * in)1582 static void yaffs_invalidate_whole_cache(struct yaffs_obj *in)
1583 {
1584 	int i;
1585 	struct yaffs_dev *dev = in->my_dev;
1586 
1587 	if (dev->param.n_caches > 0) {
1588 		/* Invalidate it. */
1589 		for (i = 0; i < dev->param.n_caches; i++) {
1590 			if (dev->cache[i].object == in)
1591 				dev->cache[i].object = NULL;
1592 		}
1593 	}
1594 }
1595 
yaffs_unhash_obj(struct yaffs_obj * obj)1596 static void yaffs_unhash_obj(struct yaffs_obj *obj)
1597 {
1598 	int bucket;
1599 	struct yaffs_dev *dev = obj->my_dev;
1600 
1601 	/* If it is still linked into the bucket list, free from the list */
1602 	if (!list_empty(&obj->hash_link)) {
1603 		list_del_init(&obj->hash_link);
1604 		bucket = yaffs_hash_fn(obj->obj_id);
1605 		dev->obj_bucket[bucket].count--;
1606 	}
1607 }
1608 
1609 /*  FreeObject frees up a Object and puts it back on the free list */
yaffs_free_obj(struct yaffs_obj * obj)1610 static void yaffs_free_obj(struct yaffs_obj *obj)
1611 {
1612 	struct yaffs_dev *dev;
1613 
1614 	if (!obj) {
1615 		BUG();
1616 		return;
1617 	}
1618 	dev = obj->my_dev;
1619 	yaffs_trace(YAFFS_TRACE_OS, "FreeObject %p inode %p",
1620 		obj, obj->my_inode);
1621 	if (obj->parent)
1622 		BUG();
1623 	if (!list_empty(&obj->siblings))
1624 		BUG();
1625 
1626 	if (obj->my_inode) {
1627 		/* We're still hooked up to a cached inode.
1628 		 * Don't delete now, but mark for later deletion
1629 		 */
1630 		obj->defered_free = 1;
1631 		return;
1632 	}
1633 
1634 	yaffs_unhash_obj(obj);
1635 
1636 	yaffs_free_raw_obj(dev, obj);
1637 	dev->n_obj--;
1638 	dev->checkpoint_blocks_required = 0;	/* force recalculation */
1639 }
1640 
yaffs_handle_defered_free(struct yaffs_obj * obj)1641 void yaffs_handle_defered_free(struct yaffs_obj *obj)
1642 {
1643 	if (obj->defered_free)
1644 		yaffs_free_obj(obj);
1645 }
1646 
yaffs_generic_obj_del(struct yaffs_obj * in)1647 static int yaffs_generic_obj_del(struct yaffs_obj *in)
1648 {
1649 	/* Iinvalidate the file's data in the cache, without flushing. */
1650 	yaffs_invalidate_whole_cache(in);
1651 
1652 	if (in->my_dev->param.is_yaffs2 && in->parent != in->my_dev->del_dir) {
1653 		/* Move to unlinked directory so we have a deletion record */
1654 		yaffs_change_obj_name(in, in->my_dev->del_dir, _Y("deleted"), 0,
1655 				      0);
1656 	}
1657 
1658 	yaffs_remove_obj_from_dir(in);
1659 	yaffs_chunk_del(in->my_dev, in->hdr_chunk, 1, __LINE__);
1660 	in->hdr_chunk = 0;
1661 
1662 	yaffs_free_obj(in);
1663 	return YAFFS_OK;
1664 
1665 }
1666 
yaffs_soft_del_file(struct yaffs_obj * obj)1667 static void yaffs_soft_del_file(struct yaffs_obj *obj)
1668 {
1669 	if (!obj->deleted ||
1670 	    obj->variant_type != YAFFS_OBJECT_TYPE_FILE ||
1671 	    obj->soft_del)
1672 		return;
1673 
1674 	if (obj->n_data_chunks <= 0) {
1675 		/* Empty file with no duplicate object headers,
1676 		 * just delete it immediately */
1677 		yaffs_free_tnode(obj->my_dev, obj->variant.file_variant.top);
1678 		obj->variant.file_variant.top = NULL;
1679 		yaffs_trace(YAFFS_TRACE_TRACING,
1680 			"yaffs: Deleting empty file %d",
1681 			obj->obj_id);
1682 		yaffs_generic_obj_del(obj);
1683 	} else {
1684 		yaffs_soft_del_worker(obj,
1685 				      obj->variant.file_variant.top,
1686 				      obj->variant.
1687 				      file_variant.top_level, 0);
1688 		obj->soft_del = 1;
1689 	}
1690 }
1691 
1692 /* Pruning removes any part of the file structure tree that is beyond the
1693  * bounds of the file (ie that does not point to chunks).
1694  *
1695  * A file should only get pruned when its size is reduced.
1696  *
1697  * Before pruning, the chunks must be pulled from the tree and the
1698  * level 0 tnode entries must be zeroed out.
1699  * Could also use this for file deletion, but that's probably better handled
1700  * by a special case.
1701  *
1702  * This function is recursive. For levels > 0 the function is called again on
1703  * any sub-tree. For level == 0 we just check if the sub-tree has data.
1704  * If there is no data in a subtree then it is pruned.
1705  */
1706 
yaffs_prune_worker(struct yaffs_dev * dev,struct yaffs_tnode * tn,u32 level,int del0)1707 static struct yaffs_tnode *yaffs_prune_worker(struct yaffs_dev *dev,
1708 					      struct yaffs_tnode *tn, u32 level,
1709 					      int del0)
1710 {
1711 	int i;
1712 	int has_data;
1713 
1714 	if (!tn)
1715 		return tn;
1716 
1717 	has_data = 0;
1718 
1719 	if (level > 0) {
1720 		for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
1721 			if (tn->internal[i]) {
1722 				tn->internal[i] =
1723 				    yaffs_prune_worker(dev,
1724 						tn->internal[i],
1725 						level - 1,
1726 						(i == 0) ? del0 : 1);
1727 			}
1728 
1729 			if (tn->internal[i])
1730 				has_data++;
1731 		}
1732 	} else {
1733 		int tnode_size_u32 = dev->tnode_size / sizeof(u32);
1734 		u32 *map = (u32 *) tn;
1735 
1736 		for (i = 0; !has_data && i < tnode_size_u32; i++) {
1737 			if (map[i])
1738 				has_data++;
1739 		}
1740 	}
1741 
1742 	if (has_data == 0 && del0) {
1743 		/* Free and return NULL */
1744 		yaffs_free_tnode(dev, tn);
1745 		tn = NULL;
1746 	}
1747 	return tn;
1748 }
1749 
yaffs_prune_tree(struct yaffs_dev * dev,struct yaffs_file_var * file_struct)1750 static int yaffs_prune_tree(struct yaffs_dev *dev,
1751 			    struct yaffs_file_var *file_struct)
1752 {
1753 	int i;
1754 	int has_data;
1755 	int done = 0;
1756 	struct yaffs_tnode *tn;
1757 
1758 	if (file_struct->top_level < 1)
1759 		return YAFFS_OK;
1760 
1761 	file_struct->top =
1762 	   yaffs_prune_worker(dev, file_struct->top, file_struct->top_level, 0);
1763 
1764 	/* Now we have a tree with all the non-zero branches NULL but
1765 	 * the height is the same as it was.
1766 	 * Let's see if we can trim internal tnodes to shorten the tree.
1767 	 * We can do this if only the 0th element in the tnode is in use
1768 	 * (ie all the non-zero are NULL)
1769 	 */
1770 
1771 	while (file_struct->top_level && !done) {
1772 		tn = file_struct->top;
1773 
1774 		has_data = 0;
1775 		for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
1776 			if (tn->internal[i])
1777 				has_data++;
1778 		}
1779 
1780 		if (!has_data) {
1781 			file_struct->top = tn->internal[0];
1782 			file_struct->top_level--;
1783 			yaffs_free_tnode(dev, tn);
1784 		} else {
1785 			done = 1;
1786 		}
1787 	}
1788 
1789 	return YAFFS_OK;
1790 }
1791 
1792 /*-------------------- End of File Structure functions.-------------------*/
1793 
1794 /* alloc_empty_obj gets us a clean Object.*/
yaffs_alloc_empty_obj(struct yaffs_dev * dev)1795 static struct yaffs_obj *yaffs_alloc_empty_obj(struct yaffs_dev *dev)
1796 {
1797 	struct yaffs_obj *obj = yaffs_alloc_raw_obj(dev);
1798 
1799 	if (!obj)
1800 		return obj;
1801 
1802 	dev->n_obj++;
1803 
1804 	/* Now sweeten it up... */
1805 
1806 	memset(obj, 0, sizeof(struct yaffs_obj));
1807 	obj->being_created = 1;
1808 
1809 	obj->my_dev = dev;
1810 	obj->hdr_chunk = 0;
1811 	obj->variant_type = YAFFS_OBJECT_TYPE_UNKNOWN;
1812 	INIT_LIST_HEAD(&(obj->hard_links));
1813 	INIT_LIST_HEAD(&(obj->hash_link));
1814 	INIT_LIST_HEAD(&obj->siblings);
1815 
1816 	/* Now make the directory sane */
1817 	if (dev->root_dir) {
1818 		obj->parent = dev->root_dir;
1819 		list_add(&(obj->siblings),
1820 			 &dev->root_dir->variant.dir_variant.children);
1821 	}
1822 
1823 	/* Add it to the lost and found directory.
1824 	 * NB Can't put root or lost-n-found in lost-n-found so
1825 	 * check if lost-n-found exists first
1826 	 */
1827 	if (dev->lost_n_found)
1828 		yaffs_add_obj_to_dir(dev->lost_n_found, obj);
1829 
1830 	obj->being_created = 0;
1831 
1832 	dev->checkpoint_blocks_required = 0;	/* force recalculation */
1833 
1834 	return obj;
1835 }
1836 
yaffs_find_nice_bucket(struct yaffs_dev * dev)1837 static int yaffs_find_nice_bucket(struct yaffs_dev *dev)
1838 {
1839 	int i;
1840 	int l = 999;
1841 	int lowest = 999999;
1842 
1843 	/* Search for the shortest list or one that
1844 	 * isn't too long.
1845 	 */
1846 
1847 	for (i = 0; i < 10 && lowest > 4; i++) {
1848 		dev->bucket_finder++;
1849 		dev->bucket_finder %= YAFFS_NOBJECT_BUCKETS;
1850 		if (dev->obj_bucket[dev->bucket_finder].count < lowest) {
1851 			lowest = dev->obj_bucket[dev->bucket_finder].count;
1852 			l = dev->bucket_finder;
1853 		}
1854 	}
1855 
1856 	return l;
1857 }
1858 
yaffs_new_obj_id(struct yaffs_dev * dev)1859 static int yaffs_new_obj_id(struct yaffs_dev *dev)
1860 {
1861 	int bucket = yaffs_find_nice_bucket(dev);
1862 	int found = 0;
1863 	struct list_head *i;
1864 	u32 n = (u32) bucket;
1865 
1866 	/* Now find an object value that has not already been taken
1867 	 * by scanning the list.
1868 	 */
1869 
1870 	while (!found) {
1871 		found = 1;
1872 		n += YAFFS_NOBJECT_BUCKETS;
1873 		list_for_each(i, &dev->obj_bucket[bucket].list) {
1874 			/* If there is already one in the list */
1875 			if (list_entry(i, struct yaffs_obj,
1876 				       hash_link)->obj_id == n) {
1877 				found = 0;
1878 				break;
1879 			}
1880 		}
1881 	}
1882 	return n;
1883 }
1884 
yaffs_hash_obj(struct yaffs_obj * in)1885 static void yaffs_hash_obj(struct yaffs_obj *in)
1886 {
1887 	int bucket = yaffs_hash_fn(in->obj_id);
1888 	struct yaffs_dev *dev = in->my_dev;
1889 
1890 	list_add(&in->hash_link, &dev->obj_bucket[bucket].list);
1891 	dev->obj_bucket[bucket].count++;
1892 }
1893 
yaffs_find_by_number(struct yaffs_dev * dev,u32 number)1894 struct yaffs_obj *yaffs_find_by_number(struct yaffs_dev *dev, u32 number)
1895 {
1896 	int bucket = yaffs_hash_fn(number);
1897 	struct list_head *i;
1898 	struct yaffs_obj *in;
1899 
1900 	list_for_each(i, &dev->obj_bucket[bucket].list) {
1901 		/* Look if it is in the list */
1902 		in = list_entry(i, struct yaffs_obj, hash_link);
1903 		if (in->obj_id == number) {
1904 			/* Don't show if it is defered free */
1905 			if (in->defered_free)
1906 				return NULL;
1907 			return in;
1908 		}
1909 	}
1910 
1911 	return NULL;
1912 }
1913 
yaffs_new_obj(struct yaffs_dev * dev,int number,enum yaffs_obj_type type)1914 struct yaffs_obj *yaffs_new_obj(struct yaffs_dev *dev, int number,
1915 				enum yaffs_obj_type type)
1916 {
1917 	struct yaffs_obj *the_obj = NULL;
1918 	struct yaffs_tnode *tn = NULL;
1919 
1920 	if (number < 0)
1921 		number = yaffs_new_obj_id(dev);
1922 
1923 	if (type == YAFFS_OBJECT_TYPE_FILE) {
1924 		tn = yaffs_get_tnode(dev);
1925 		if (!tn)
1926 			return NULL;
1927 	}
1928 
1929 	the_obj = yaffs_alloc_empty_obj(dev);
1930 	if (!the_obj) {
1931 		if (tn)
1932 			yaffs_free_tnode(dev, tn);
1933 		return NULL;
1934 	}
1935 
1936 	the_obj->fake = 0;
1937 	the_obj->rename_allowed = 1;
1938 	the_obj->unlink_allowed = 1;
1939 	the_obj->obj_id = number;
1940 	yaffs_hash_obj(the_obj);
1941 	the_obj->variant_type = type;
1942 	yaffs_load_current_time(the_obj, 1, 1);
1943 
1944 	switch (type) {
1945 	case YAFFS_OBJECT_TYPE_FILE:
1946 		the_obj->variant.file_variant.file_size = 0;
1947 		the_obj->variant.file_variant.scanned_size = 0;
1948 		the_obj->variant.file_variant.shrink_size =
1949 						yaffs_max_file_size(dev);
1950 		the_obj->variant.file_variant.top_level = 0;
1951 		the_obj->variant.file_variant.top = tn;
1952 		break;
1953 	case YAFFS_OBJECT_TYPE_DIRECTORY:
1954 		INIT_LIST_HEAD(&the_obj->variant.dir_variant.children);
1955 		INIT_LIST_HEAD(&the_obj->variant.dir_variant.dirty);
1956 		break;
1957 	case YAFFS_OBJECT_TYPE_SYMLINK:
1958 	case YAFFS_OBJECT_TYPE_HARDLINK:
1959 	case YAFFS_OBJECT_TYPE_SPECIAL:
1960 		/* No action required */
1961 		break;
1962 	case YAFFS_OBJECT_TYPE_UNKNOWN:
1963 		/* todo this should not happen */
1964 		break;
1965 	}
1966 	return the_obj;
1967 }
1968 
yaffs_create_fake_dir(struct yaffs_dev * dev,int number,u32 mode)1969 static struct yaffs_obj *yaffs_create_fake_dir(struct yaffs_dev *dev,
1970 					       int number, u32 mode)
1971 {
1972 
1973 	struct yaffs_obj *obj =
1974 	    yaffs_new_obj(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
1975 
1976 	if (!obj)
1977 		return NULL;
1978 
1979 	obj->fake = 1;	/* it is fake so it might not use NAND */
1980 	obj->rename_allowed = 0;
1981 	obj->unlink_allowed = 0;
1982 	obj->deleted = 0;
1983 	obj->unlinked = 0;
1984 	obj->yst_mode = mode;
1985 	obj->my_dev = dev;
1986 	obj->hdr_chunk = 0;	/* Not a valid chunk. */
1987 	return obj;
1988 
1989 }
1990 
1991 
yaffs_init_tnodes_and_objs(struct yaffs_dev * dev)1992 static void yaffs_init_tnodes_and_objs(struct yaffs_dev *dev)
1993 {
1994 	int i;
1995 
1996 	dev->n_obj = 0;
1997 	dev->n_tnodes = 0;
1998 	yaffs_init_raw_tnodes_and_objs(dev);
1999 
2000 	for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
2001 		INIT_LIST_HEAD(&dev->obj_bucket[i].list);
2002 		dev->obj_bucket[i].count = 0;
2003 	}
2004 }
2005 
yaffs_find_or_create_by_number(struct yaffs_dev * dev,int number,enum yaffs_obj_type type)2006 struct yaffs_obj *yaffs_find_or_create_by_number(struct yaffs_dev *dev,
2007 						 int number,
2008 						 enum yaffs_obj_type type)
2009 {
2010 	struct yaffs_obj *the_obj = NULL;
2011 
2012 	if (number > 0)
2013 		the_obj = yaffs_find_by_number(dev, number);
2014 
2015 	if (!the_obj)
2016 		the_obj = yaffs_new_obj(dev, number, type);
2017 
2018 	return the_obj;
2019 
2020 }
2021 
yaffs_clone_str(const YCHAR * str)2022 YCHAR *yaffs_clone_str(const YCHAR *str)
2023 {
2024 	YCHAR *new_str = NULL;
2025 	int len;
2026 
2027 	if (!str)
2028 		str = _Y("");
2029 
2030 	len = yaffs_strnlen(str, YAFFS_MAX_ALIAS_LENGTH);
2031 	new_str = kmalloc((len + 1) * sizeof(YCHAR), GFP_NOFS);
2032 	if (new_str) {
2033 		yaffs_strncpy(new_str, str, len);
2034 		new_str[len] = 0;
2035 	}
2036 	return new_str;
2037 
2038 }
2039 /*
2040  *yaffs_update_parent() handles fixing a directories mtime and ctime when a new
2041  * link (ie. name) is created or deleted in the directory.
2042  *
2043  * ie.
2044  *   create dir/a : update dir's mtime/ctime
2045  *   rm dir/a:   update dir's mtime/ctime
2046  *   modify dir/a: don't update dir's mtimme/ctime
2047  *
2048  * This can be handled immediately or defered. Defering helps reduce the number
2049  * of updates when many files in a directory are changed within a brief period.
2050  *
2051  * If the directory updating is defered then yaffs_update_dirty_dirs must be
2052  * called periodically.
2053  */
2054 
yaffs_update_parent(struct yaffs_obj * obj)2055 static void yaffs_update_parent(struct yaffs_obj *obj)
2056 {
2057 	struct yaffs_dev *dev;
2058 
2059 	if (!obj)
2060 		return;
2061 	dev = obj->my_dev;
2062 	obj->dirty = 1;
2063 	yaffs_load_current_time(obj, 0, 1);
2064 	if (dev->param.defered_dir_update) {
2065 		struct list_head *link = &obj->variant.dir_variant.dirty;
2066 
2067 		if (list_empty(link)) {
2068 			list_add(link, &dev->dirty_dirs);
2069 			yaffs_trace(YAFFS_TRACE_BACKGROUND,
2070 			  "Added object %d to dirty directories",
2071 			   obj->obj_id);
2072 		}
2073 
2074 	} else {
2075 		yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
2076 	}
2077 }
2078 
yaffs_update_dirty_dirs(struct yaffs_dev * dev)2079 void yaffs_update_dirty_dirs(struct yaffs_dev *dev)
2080 {
2081 	struct list_head *link;
2082 	struct yaffs_obj *obj;
2083 	struct yaffs_dir_var *d_s;
2084 	union yaffs_obj_var *o_v;
2085 
2086 	yaffs_trace(YAFFS_TRACE_BACKGROUND, "Update dirty directories");
2087 
2088 	while (!list_empty(&dev->dirty_dirs)) {
2089 		link = dev->dirty_dirs.next;
2090 		list_del_init(link);
2091 
2092 		d_s = list_entry(link, struct yaffs_dir_var, dirty);
2093 		o_v = list_entry(d_s, union yaffs_obj_var, dir_variant);
2094 		obj = list_entry(o_v, struct yaffs_obj, variant);
2095 
2096 		yaffs_trace(YAFFS_TRACE_BACKGROUND, "Update directory %d",
2097 			obj->obj_id);
2098 
2099 		if (obj->dirty)
2100 			yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
2101 	}
2102 }
2103 
2104 /*
2105  * Mknod (create) a new object.
2106  * equiv_obj only has meaning for a hard link;
2107  * alias_str only has meaning for a symlink.
2108  * rdev only has meaning for devices (a subset of special objects)
2109  */
2110 
yaffs_create_obj(enum yaffs_obj_type type,struct yaffs_obj * parent,const YCHAR * name,u32 mode,u32 uid,u32 gid,struct yaffs_obj * equiv_obj,const YCHAR * alias_str,u32 rdev)2111 static struct yaffs_obj *yaffs_create_obj(enum yaffs_obj_type type,
2112 					  struct yaffs_obj *parent,
2113 					  const YCHAR *name,
2114 					  u32 mode,
2115 					  u32 uid,
2116 					  u32 gid,
2117 					  struct yaffs_obj *equiv_obj,
2118 					  const YCHAR *alias_str, u32 rdev)
2119 {
2120 	struct yaffs_obj *in;
2121 	YCHAR *str = NULL;
2122 	struct yaffs_dev *dev = parent->my_dev;
2123 
2124 	/* Check if the entry exists.
2125 	 * If it does then fail the call since we don't want a dup. */
2126 	if (yaffs_find_by_name(parent, name))
2127 		return NULL;
2128 
2129 	if (type == YAFFS_OBJECT_TYPE_SYMLINK) {
2130 		str = yaffs_clone_str(alias_str);
2131 		if (!str)
2132 			return NULL;
2133 	}
2134 
2135 	in = yaffs_new_obj(dev, -1, type);
2136 
2137 	if (!in) {
2138 		kfree(str);
2139 		return NULL;
2140 	}
2141 
2142 	in->hdr_chunk = 0;
2143 	in->valid = 1;
2144 	in->variant_type = type;
2145 
2146 	in->yst_mode = mode;
2147 
2148 	yaffs_attribs_init(in, gid, uid, rdev);
2149 
2150 	in->n_data_chunks = 0;
2151 
2152 	yaffs_set_obj_name(in, name);
2153 	in->dirty = 1;
2154 
2155 	yaffs_add_obj_to_dir(parent, in);
2156 
2157 	in->my_dev = parent->my_dev;
2158 
2159 	switch (type) {
2160 	case YAFFS_OBJECT_TYPE_SYMLINK:
2161 		in->variant.symlink_variant.alias = str;
2162 		break;
2163 	case YAFFS_OBJECT_TYPE_HARDLINK:
2164 		in->variant.hardlink_variant.equiv_obj = equiv_obj;
2165 		in->variant.hardlink_variant.equiv_id = equiv_obj->obj_id;
2166 		list_add(&in->hard_links, &equiv_obj->hard_links);
2167 		break;
2168 	case YAFFS_OBJECT_TYPE_FILE:
2169 	case YAFFS_OBJECT_TYPE_DIRECTORY:
2170 	case YAFFS_OBJECT_TYPE_SPECIAL:
2171 	case YAFFS_OBJECT_TYPE_UNKNOWN:
2172 		/* do nothing */
2173 		break;
2174 	}
2175 
2176 	if (yaffs_update_oh(in, name, 0, 0, 0, NULL) < 0) {
2177 		/* Could not create the object header, fail */
2178 		yaffs_del_obj(in);
2179 		in = NULL;
2180 	}
2181 
2182 	if (in)
2183 		yaffs_update_parent(parent);
2184 
2185 	return in;
2186 }
2187 
yaffs_create_file(struct yaffs_obj * parent,const YCHAR * name,u32 mode,u32 uid,u32 gid)2188 struct yaffs_obj *yaffs_create_file(struct yaffs_obj *parent,
2189 				    const YCHAR *name, u32 mode, u32 uid,
2190 				    u32 gid)
2191 {
2192 	return yaffs_create_obj(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
2193 				uid, gid, NULL, NULL, 0);
2194 }
2195 
yaffs_create_dir(struct yaffs_obj * parent,const YCHAR * name,u32 mode,u32 uid,u32 gid)2196 struct yaffs_obj *yaffs_create_dir(struct yaffs_obj *parent, const YCHAR *name,
2197 				   u32 mode, u32 uid, u32 gid)
2198 {
2199 	return yaffs_create_obj(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
2200 				mode, uid, gid, NULL, NULL, 0);
2201 }
2202 
yaffs_create_special(struct yaffs_obj * parent,const YCHAR * name,u32 mode,u32 uid,u32 gid,u32 rdev)2203 struct yaffs_obj *yaffs_create_special(struct yaffs_obj *parent,
2204 				       const YCHAR *name, u32 mode, u32 uid,
2205 				       u32 gid, u32 rdev)
2206 {
2207 	return yaffs_create_obj(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
2208 				uid, gid, NULL, NULL, rdev);
2209 }
2210 
yaffs_create_symlink(struct yaffs_obj * parent,const YCHAR * name,u32 mode,u32 uid,u32 gid,const YCHAR * alias)2211 struct yaffs_obj *yaffs_create_symlink(struct yaffs_obj *parent,
2212 				       const YCHAR *name, u32 mode, u32 uid,
2213 				       u32 gid, const YCHAR *alias)
2214 {
2215 	return yaffs_create_obj(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
2216 				uid, gid, NULL, alias, 0);
2217 }
2218 
2219 /* yaffs_link_obj returns the object id of the equivalent object.*/
yaffs_link_obj(struct yaffs_obj * parent,const YCHAR * name,struct yaffs_obj * equiv_obj)2220 struct yaffs_obj *yaffs_link_obj(struct yaffs_obj *parent, const YCHAR * name,
2221 				 struct yaffs_obj *equiv_obj)
2222 {
2223 	/* Get the real object in case we were fed a hard link obj */
2224 	equiv_obj = yaffs_get_equivalent_obj(equiv_obj);
2225 
2226 	if (yaffs_create_obj(YAFFS_OBJECT_TYPE_HARDLINK,
2227 			parent, name, 0, 0, 0,
2228 			equiv_obj, NULL, 0))
2229 		return equiv_obj;
2230 
2231 	return NULL;
2232 
2233 }
2234 
2235 
2236 
2237 /*---------------------- Block Management and Page Allocation -------------*/
2238 
yaffs_deinit_blocks(struct yaffs_dev * dev)2239 static void yaffs_deinit_blocks(struct yaffs_dev *dev)
2240 {
2241 	if (dev->block_info_alt && dev->block_info)
2242 		vfree(dev->block_info);
2243 	else
2244 		kfree(dev->block_info);
2245 
2246 	dev->block_info_alt = 0;
2247 
2248 	dev->block_info = NULL;
2249 
2250 	if (dev->chunk_bits_alt && dev->chunk_bits)
2251 		vfree(dev->chunk_bits);
2252 	else
2253 		kfree(dev->chunk_bits);
2254 	dev->chunk_bits_alt = 0;
2255 	dev->chunk_bits = NULL;
2256 }
2257 
yaffs_init_blocks(struct yaffs_dev * dev)2258 static int yaffs_init_blocks(struct yaffs_dev *dev)
2259 {
2260 	int n_blocks = dev->internal_end_block - dev->internal_start_block + 1;
2261 
2262 	dev->block_info = NULL;
2263 	dev->chunk_bits = NULL;
2264 	dev->alloc_block = -1;	/* force it to get a new one */
2265 
2266 	/* If the first allocation strategy fails, thry the alternate one */
2267 	dev->block_info =
2268 		kmalloc(n_blocks * sizeof(struct yaffs_block_info), GFP_NOFS);
2269 	if (!dev->block_info) {
2270 		dev->block_info =
2271 		    vmalloc(n_blocks * sizeof(struct yaffs_block_info));
2272 		dev->block_info_alt = 1;
2273 	} else {
2274 		dev->block_info_alt = 0;
2275 	}
2276 
2277 	if (!dev->block_info)
2278 		goto alloc_error;
2279 
2280 	/* Set up dynamic blockinfo stuff. Round up bytes. */
2281 	dev->chunk_bit_stride = (dev->param.chunks_per_block + 7) / 8;
2282 	dev->chunk_bits =
2283 		kmalloc(dev->chunk_bit_stride * n_blocks, GFP_NOFS);
2284 	if (!dev->chunk_bits) {
2285 		dev->chunk_bits =
2286 		    vmalloc(dev->chunk_bit_stride * n_blocks);
2287 		dev->chunk_bits_alt = 1;
2288 	} else {
2289 		dev->chunk_bits_alt = 0;
2290 	}
2291 	if (!dev->chunk_bits)
2292 		goto alloc_error;
2293 
2294 
2295 	memset(dev->block_info, 0, n_blocks * sizeof(struct yaffs_block_info));
2296 	memset(dev->chunk_bits, 0, dev->chunk_bit_stride * n_blocks);
2297 	return YAFFS_OK;
2298 
2299 alloc_error:
2300 	yaffs_deinit_blocks(dev);
2301 	return YAFFS_FAIL;
2302 }
2303 
2304 
yaffs_block_became_dirty(struct yaffs_dev * dev,int block_no)2305 void yaffs_block_became_dirty(struct yaffs_dev *dev, int block_no)
2306 {
2307 	struct yaffs_block_info *bi = yaffs_get_block_info(dev, block_no);
2308 	int erased_ok = 0;
2309 	int i;
2310 
2311 	/* If the block is still healthy erase it and mark as clean.
2312 	 * If the block has had a data failure, then retire it.
2313 	 */
2314 
2315 	yaffs_trace(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
2316 		"yaffs_block_became_dirty block %d state %d %s",
2317 		block_no, bi->block_state,
2318 		(bi->needs_retiring) ? "needs retiring" : "");
2319 
2320 	yaffs2_clear_oldest_dirty_seq(dev, bi);
2321 
2322 	bi->block_state = YAFFS_BLOCK_STATE_DIRTY;
2323 
2324 	/* If this is the block being garbage collected then stop gc'ing */
2325 	if (block_no == dev->gc_block)
2326 		dev->gc_block = 0;
2327 
2328 	/* If this block is currently the best candidate for gc
2329 	 * then drop as a candidate */
2330 	if (block_no == dev->gc_dirtiest) {
2331 		dev->gc_dirtiest = 0;
2332 		dev->gc_pages_in_use = 0;
2333 	}
2334 
2335 	if (!bi->needs_retiring) {
2336 		yaffs2_checkpt_invalidate(dev);
2337 		erased_ok = yaffs_erase_block(dev, block_no);
2338 		if (!erased_ok) {
2339 			dev->n_erase_failures++;
2340 			yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2341 			  "**>> Erasure failed %d", block_no);
2342 		}
2343 	}
2344 
2345 	/* Verify erasure if needed */
2346 	if (erased_ok &&
2347 	    ((yaffs_trace_mask & YAFFS_TRACE_ERASE) ||
2348 	     !yaffs_skip_verification(dev))) {
2349 		for (i = 0; i < dev->param.chunks_per_block; i++) {
2350 			if (!yaffs_check_chunk_erased(dev,
2351 				block_no * dev->param.chunks_per_block + i)) {
2352 				yaffs_trace(YAFFS_TRACE_ERROR,
2353 					">>Block %d erasure supposedly OK, but chunk %d not erased",
2354 					block_no, i);
2355 			}
2356 		}
2357 	}
2358 
2359 	if (!erased_ok) {
2360 		/* We lost a block of free space */
2361 		dev->n_free_chunks -= dev->param.chunks_per_block;
2362 		yaffs_retire_block(dev, block_no);
2363 		yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2364 			"**>> Block %d retired", block_no);
2365 		return;
2366 	}
2367 
2368 	/* Clean it up... */
2369 	bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
2370 	bi->seq_number = 0;
2371 	dev->n_erased_blocks++;
2372 	bi->pages_in_use = 0;
2373 	bi->soft_del_pages = 0;
2374 	bi->has_shrink_hdr = 0;
2375 	bi->skip_erased_check = 1;	/* Clean, so no need to check */
2376 	bi->gc_prioritise = 0;
2377 	bi->has_summary = 0;
2378 
2379 	yaffs_clear_chunk_bits(dev, block_no);
2380 
2381 	yaffs_trace(YAFFS_TRACE_ERASE, "Erased block %d", block_no);
2382 }
2383 
yaffs_gc_process_chunk(struct yaffs_dev * dev,struct yaffs_block_info * bi,int old_chunk,u8 * buffer)2384 static inline int yaffs_gc_process_chunk(struct yaffs_dev *dev,
2385 					struct yaffs_block_info *bi,
2386 					int old_chunk, u8 *buffer)
2387 {
2388 	int new_chunk;
2389 	int mark_flash = 1;
2390 	struct yaffs_ext_tags tags;
2391 	struct yaffs_obj *object;
2392 	int matching_chunk;
2393 	int ret_val = YAFFS_OK;
2394 
2395 	memset(&tags, 0, sizeof(tags));
2396 	yaffs_rd_chunk_tags_nand(dev, old_chunk,
2397 				 buffer, &tags);
2398 	object = yaffs_find_by_number(dev, tags.obj_id);
2399 
2400 	yaffs_trace(YAFFS_TRACE_GC_DETAIL,
2401 		"Collecting chunk in block %d, %d %d %d ",
2402 		dev->gc_chunk, tags.obj_id,
2403 		tags.chunk_id, tags.n_bytes);
2404 
2405 	if (object && !yaffs_skip_verification(dev)) {
2406 		if (tags.chunk_id == 0)
2407 			matching_chunk =
2408 			    object->hdr_chunk;
2409 		else if (object->soft_del)
2410 			/* Defeat the test */
2411 			matching_chunk = old_chunk;
2412 		else
2413 			matching_chunk =
2414 			    yaffs_find_chunk_in_file
2415 			    (object, tags.chunk_id,
2416 			     NULL);
2417 
2418 		if (old_chunk != matching_chunk)
2419 			yaffs_trace(YAFFS_TRACE_ERROR,
2420 				"gc: page in gc mismatch: %d %d %d %d",
2421 				old_chunk,
2422 				matching_chunk,
2423 				tags.obj_id,
2424 				tags.chunk_id);
2425 	}
2426 
2427 	if (!object) {
2428 		yaffs_trace(YAFFS_TRACE_ERROR,
2429 			"page %d in gc has no object: %d %d %d ",
2430 			old_chunk,
2431 			tags.obj_id, tags.chunk_id,
2432 			tags.n_bytes);
2433 	}
2434 
2435 	if (object &&
2436 	    object->deleted &&
2437 	    object->soft_del && tags.chunk_id != 0) {
2438 		/* Data chunk in a soft deleted file,
2439 		 * throw it away.
2440 		 * It's a soft deleted data chunk,
2441 		 * No need to copy this, just forget
2442 		 * about it and fix up the object.
2443 		 */
2444 
2445 		/* Free chunks already includes
2446 		 * softdeleted chunks, how ever this
2447 		 * chunk is going to soon be really
2448 		 * deleted which will increment free
2449 		 * chunks. We have to decrement free
2450 		 * chunks so this works out properly.
2451 		 */
2452 		dev->n_free_chunks--;
2453 		bi->soft_del_pages--;
2454 
2455 		object->n_data_chunks--;
2456 		if (object->n_data_chunks <= 0) {
2457 			/* remeber to clean up obj */
2458 			dev->gc_cleanup_list[dev->n_clean_ups] = tags.obj_id;
2459 			dev->n_clean_ups++;
2460 		}
2461 		mark_flash = 0;
2462 	} else if (object) {
2463 		/* It's either a data chunk in a live
2464 		 * file or an ObjectHeader, so we're
2465 		 * interested in it.
2466 		 * NB Need to keep the ObjectHeaders of
2467 		 * deleted files until the whole file
2468 		 * has been deleted off
2469 		 */
2470 		tags.serial_number++;
2471 		dev->n_gc_copies++;
2472 
2473 		if (tags.chunk_id == 0) {
2474 			/* It is an object Id,
2475 			 * We need to nuke the
2476 			 * shrinkheader flags since its
2477 			 * work is done.
2478 			 * Also need to clean up
2479 			 * shadowing.
2480 			 */
2481 			struct yaffs_obj_hdr *oh;
2482 			oh = (struct yaffs_obj_hdr *) buffer;
2483 
2484 			oh->is_shrink = 0;
2485 			tags.extra_is_shrink = 0;
2486 			oh->shadows_obj = 0;
2487 			oh->inband_shadowed_obj_id = 0;
2488 			tags.extra_shadows = 0;
2489 
2490 			/* Update file size */
2491 			if (object->variant_type == YAFFS_OBJECT_TYPE_FILE) {
2492 				yaffs_oh_size_load(oh,
2493 				    object->variant.file_variant.file_size);
2494 				tags.extra_file_size =
2495 				    object->variant.file_variant.file_size;
2496 			}
2497 
2498 			yaffs_verify_oh(object, oh, &tags, 1);
2499 			new_chunk =
2500 			    yaffs_write_new_chunk(dev, (u8 *) oh, &tags, 1);
2501 		} else {
2502 			new_chunk =
2503 			    yaffs_write_new_chunk(dev, buffer, &tags, 1);
2504 		}
2505 
2506 		if (new_chunk < 0) {
2507 			ret_val = YAFFS_FAIL;
2508 		} else {
2509 
2510 			/* Now fix up the Tnodes etc. */
2511 
2512 			if (tags.chunk_id == 0) {
2513 				/* It's a header */
2514 				object->hdr_chunk = new_chunk;
2515 				object->serial = tags.serial_number;
2516 			} else {
2517 				/* It's a data chunk */
2518 				yaffs_put_chunk_in_file(object, tags.chunk_id,
2519 							new_chunk, 0);
2520 			}
2521 		}
2522 	}
2523 	if (ret_val == YAFFS_OK)
2524 		yaffs_chunk_del(dev, old_chunk, mark_flash, __LINE__);
2525 	return ret_val;
2526 }
2527 
yaffs_gc_block(struct yaffs_dev * dev,int block,int whole_block)2528 static int yaffs_gc_block(struct yaffs_dev *dev, int block, int whole_block)
2529 {
2530 	int old_chunk;
2531 	int ret_val = YAFFS_OK;
2532 	int i;
2533 	int is_checkpt_block;
2534 	int max_copies;
2535 	int chunks_before = yaffs_get_erased_chunks(dev);
2536 	int chunks_after;
2537 	struct yaffs_block_info *bi = yaffs_get_block_info(dev, block);
2538 
2539 	is_checkpt_block = (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT);
2540 
2541 	yaffs_trace(YAFFS_TRACE_TRACING,
2542 		"Collecting block %d, in use %d, shrink %d, whole_block %d",
2543 		block, bi->pages_in_use, bi->has_shrink_hdr,
2544 		whole_block);
2545 
2546 	/*yaffs_verify_free_chunks(dev); */
2547 
2548 	if (bi->block_state == YAFFS_BLOCK_STATE_FULL)
2549 		bi->block_state = YAFFS_BLOCK_STATE_COLLECTING;
2550 
2551 	bi->has_shrink_hdr = 0;	/* clear the flag so that the block can erase */
2552 
2553 	dev->gc_disable = 1;
2554 
2555 	yaffs_summary_gc(dev, block);
2556 
2557 	if (is_checkpt_block || !yaffs_still_some_chunks(dev, block)) {
2558 		yaffs_trace(YAFFS_TRACE_TRACING,
2559 			"Collecting block %d that has no chunks in use",
2560 			block);
2561 		yaffs_block_became_dirty(dev, block);
2562 	} else {
2563 
2564 		u8 *buffer = yaffs_get_temp_buffer(dev);
2565 
2566 		yaffs_verify_blk(dev, bi, block);
2567 
2568 		max_copies = (whole_block) ? dev->param.chunks_per_block : 5;
2569 		old_chunk = block * dev->param.chunks_per_block + dev->gc_chunk;
2570 
2571 		for (/* init already done */ ;
2572 		     ret_val == YAFFS_OK &&
2573 		     dev->gc_chunk < dev->param.chunks_per_block &&
2574 		     (bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) &&
2575 		     max_copies > 0;
2576 		     dev->gc_chunk++, old_chunk++) {
2577 			if (yaffs_check_chunk_bit(dev, block, dev->gc_chunk)) {
2578 				/* Page is in use and might need to be copied */
2579 				max_copies--;
2580 				ret_val = yaffs_gc_process_chunk(dev, bi,
2581 							old_chunk, buffer);
2582 			}
2583 		}
2584 		yaffs_release_temp_buffer(dev, buffer);
2585 	}
2586 
2587 	yaffs_verify_collected_blk(dev, bi, block);
2588 
2589 	if (bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
2590 		/*
2591 		 * The gc did not complete. Set block state back to FULL
2592 		 * because checkpointing does not restore gc.
2593 		 */
2594 		bi->block_state = YAFFS_BLOCK_STATE_FULL;
2595 	} else {
2596 		/* The gc completed. */
2597 		/* Do any required cleanups */
2598 		for (i = 0; i < dev->n_clean_ups; i++) {
2599 			/* Time to delete the file too */
2600 			struct yaffs_obj *object =
2601 			    yaffs_find_by_number(dev, dev->gc_cleanup_list[i]);
2602 			if (object) {
2603 				yaffs_free_tnode(dev,
2604 					  object->variant.file_variant.top);
2605 				object->variant.file_variant.top = NULL;
2606 				yaffs_trace(YAFFS_TRACE_GC,
2607 					"yaffs: About to finally delete object %d",
2608 					object->obj_id);
2609 				yaffs_generic_obj_del(object);
2610 				object->my_dev->n_deleted_files--;
2611 			}
2612 
2613 		}
2614 		chunks_after = yaffs_get_erased_chunks(dev);
2615 		if (chunks_before >= chunks_after)
2616 			yaffs_trace(YAFFS_TRACE_GC,
2617 				"gc did not increase free chunks before %d after %d",
2618 				chunks_before, chunks_after);
2619 		dev->gc_block = 0;
2620 		dev->gc_chunk = 0;
2621 		dev->n_clean_ups = 0;
2622 	}
2623 
2624 	dev->gc_disable = 0;
2625 
2626 	return ret_val;
2627 }
2628 
2629 /*
2630  * find_gc_block() selects the dirtiest block (or close enough)
2631  * for garbage collection.
2632  */
2633 
yaffs_find_gc_block(struct yaffs_dev * dev,int aggressive,int background)2634 static unsigned yaffs_find_gc_block(struct yaffs_dev *dev,
2635 				    int aggressive, int background)
2636 {
2637 	int i;
2638 	int iterations;
2639 	unsigned selected = 0;
2640 	int prioritised = 0;
2641 	int prioritised_exist = 0;
2642 	struct yaffs_block_info *bi;
2643 	int threshold;
2644 
2645 	/* First let's see if we need to grab a prioritised block */
2646 	if (dev->has_pending_prioritised_gc && !aggressive) {
2647 		dev->gc_dirtiest = 0;
2648 		bi = dev->block_info;
2649 		for (i = dev->internal_start_block;
2650 		     i <= dev->internal_end_block && !selected; i++) {
2651 
2652 			if (bi->gc_prioritise) {
2653 				prioritised_exist = 1;
2654 				if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
2655 				    yaffs_block_ok_for_gc(dev, bi)) {
2656 					selected = i;
2657 					prioritised = 1;
2658 				}
2659 			}
2660 			bi++;
2661 		}
2662 
2663 		/*
2664 		 * If there is a prioritised block and none was selected then
2665 		 * this happened because there is at least one old dirty block
2666 		 * gumming up the works. Let's gc the oldest dirty block.
2667 		 */
2668 
2669 		if (prioritised_exist &&
2670 		    !selected && dev->oldest_dirty_block > 0)
2671 			selected = dev->oldest_dirty_block;
2672 
2673 		if (!prioritised_exist)	/* None found, so we can clear this */
2674 			dev->has_pending_prioritised_gc = 0;
2675 	}
2676 
2677 	/* If we're doing aggressive GC then we are happy to take a less-dirty
2678 	 * block, and search harder.
2679 	 * else (leasurely gc), then we only bother to do this if the
2680 	 * block has only a few pages in use.
2681 	 */
2682 
2683 	if (!selected) {
2684 		int pages_used;
2685 		int n_blocks =
2686 		    dev->internal_end_block - dev->internal_start_block + 1;
2687 		if (aggressive) {
2688 			threshold = dev->param.chunks_per_block;
2689 			iterations = n_blocks;
2690 		} else {
2691 			int max_threshold;
2692 
2693 			if (background)
2694 				max_threshold = dev->param.chunks_per_block / 2;
2695 			else
2696 				max_threshold = dev->param.chunks_per_block / 8;
2697 
2698 			if (max_threshold < YAFFS_GC_PASSIVE_THRESHOLD)
2699 				max_threshold = YAFFS_GC_PASSIVE_THRESHOLD;
2700 
2701 			threshold = background ? (dev->gc_not_done + 2) * 2 : 0;
2702 			if (threshold < YAFFS_GC_PASSIVE_THRESHOLD)
2703 				threshold = YAFFS_GC_PASSIVE_THRESHOLD;
2704 			if (threshold > max_threshold)
2705 				threshold = max_threshold;
2706 
2707 			iterations = n_blocks / 16 + 1;
2708 			if (iterations > 100)
2709 				iterations = 100;
2710 		}
2711 
2712 		for (i = 0;
2713 		     i < iterations &&
2714 		     (dev->gc_dirtiest < 1 ||
2715 		      dev->gc_pages_in_use > YAFFS_GC_GOOD_ENOUGH);
2716 		     i++) {
2717 			dev->gc_block_finder++;
2718 			if (dev->gc_block_finder < dev->internal_start_block ||
2719 			    dev->gc_block_finder > dev->internal_end_block)
2720 				dev->gc_block_finder =
2721 				    dev->internal_start_block;
2722 
2723 			bi = yaffs_get_block_info(dev, dev->gc_block_finder);
2724 
2725 			pages_used = bi->pages_in_use - bi->soft_del_pages;
2726 
2727 			if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
2728 			    pages_used < dev->param.chunks_per_block &&
2729 			    (dev->gc_dirtiest < 1 ||
2730 			     pages_used < dev->gc_pages_in_use) &&
2731 			    yaffs_block_ok_for_gc(dev, bi)) {
2732 				dev->gc_dirtiest = dev->gc_block_finder;
2733 				dev->gc_pages_in_use = pages_used;
2734 			}
2735 		}
2736 
2737 		if (dev->gc_dirtiest > 0 && dev->gc_pages_in_use <= threshold)
2738 			selected = dev->gc_dirtiest;
2739 	}
2740 
2741 	/*
2742 	 * If nothing has been selected for a while, try the oldest dirty
2743 	 * because that's gumming up the works.
2744 	 */
2745 
2746 	if (!selected && dev->param.is_yaffs2 &&
2747 	    dev->gc_not_done >= (background ? 10 : 20)) {
2748 		yaffs2_find_oldest_dirty_seq(dev);
2749 		if (dev->oldest_dirty_block > 0) {
2750 			selected = dev->oldest_dirty_block;
2751 			dev->gc_dirtiest = selected;
2752 			dev->oldest_dirty_gc_count++;
2753 			bi = yaffs_get_block_info(dev, selected);
2754 			dev->gc_pages_in_use =
2755 			    bi->pages_in_use - bi->soft_del_pages;
2756 		} else {
2757 			dev->gc_not_done = 0;
2758 		}
2759 	}
2760 
2761 	if (selected) {
2762 		yaffs_trace(YAFFS_TRACE_GC,
2763 			"GC Selected block %d with %d free, prioritised:%d",
2764 			selected,
2765 			dev->param.chunks_per_block - dev->gc_pages_in_use,
2766 			prioritised);
2767 
2768 		dev->n_gc_blocks++;
2769 		if (background)
2770 			dev->bg_gcs++;
2771 
2772 		dev->gc_dirtiest = 0;
2773 		dev->gc_pages_in_use = 0;
2774 		dev->gc_not_done = 0;
2775 		if (dev->refresh_skip > 0)
2776 			dev->refresh_skip--;
2777 	} else {
2778 		dev->gc_not_done++;
2779 		yaffs_trace(YAFFS_TRACE_GC,
2780 			"GC none: finder %d skip %d threshold %d dirtiest %d using %d oldest %d%s",
2781 			dev->gc_block_finder, dev->gc_not_done, threshold,
2782 			dev->gc_dirtiest, dev->gc_pages_in_use,
2783 			dev->oldest_dirty_block, background ? " bg" : "");
2784 	}
2785 
2786 	return selected;
2787 }
2788 
2789 /* New garbage collector
2790  * If we're very low on erased blocks then we do aggressive garbage collection
2791  * otherwise we do "leasurely" garbage collection.
2792  * Aggressive gc looks further (whole array) and will accept less dirty blocks.
2793  * Passive gc only inspects smaller areas and only accepts more dirty blocks.
2794  *
2795  * The idea is to help clear out space in a more spread-out manner.
2796  * Dunno if it really does anything useful.
2797  */
yaffs_check_gc(struct yaffs_dev * dev,int background)2798 static int yaffs_check_gc(struct yaffs_dev *dev, int background)
2799 {
2800 	int aggressive = 0;
2801 	int gc_ok = YAFFS_OK;
2802 	int max_tries = 0;
2803 	int min_erased;
2804 	int erased_chunks;
2805 	int checkpt_block_adjust;
2806 
2807 	if (dev->param.gc_control && (dev->param.gc_control(dev) & 1) == 0)
2808 		return YAFFS_OK;
2809 
2810 	if (dev->gc_disable)
2811 		/* Bail out so we don't get recursive gc */
2812 		return YAFFS_OK;
2813 
2814 	/* This loop should pass the first time.
2815 	 * Only loops here if the collection does not increase space.
2816 	 */
2817 
2818 	do {
2819 		max_tries++;
2820 
2821 		checkpt_block_adjust = yaffs_calc_checkpt_blocks_required(dev);
2822 
2823 		min_erased =
2824 		    dev->param.n_reserved_blocks + checkpt_block_adjust + 1;
2825 		erased_chunks =
2826 		    dev->n_erased_blocks * dev->param.chunks_per_block;
2827 
2828 		/* If we need a block soon then do aggressive gc. */
2829 		if (dev->n_erased_blocks < min_erased)
2830 			aggressive = 1;
2831 		else {
2832 			if (!background
2833 			    && erased_chunks > (dev->n_free_chunks / 4))
2834 				break;
2835 
2836 			if (dev->gc_skip > 20)
2837 				dev->gc_skip = 20;
2838 			if (erased_chunks < dev->n_free_chunks / 2 ||
2839 			    dev->gc_skip < 1 || background)
2840 				aggressive = 0;
2841 			else {
2842 				dev->gc_skip--;
2843 				break;
2844 			}
2845 		}
2846 
2847 		dev->gc_skip = 5;
2848 
2849 		/* If we don't already have a block being gc'd then see if we
2850 		 * should start another */
2851 
2852 		if (dev->gc_block < 1 && !aggressive) {
2853 			dev->gc_block = yaffs2_find_refresh_block(dev);
2854 			dev->gc_chunk = 0;
2855 			dev->n_clean_ups = 0;
2856 		}
2857 		if (dev->gc_block < 1) {
2858 			dev->gc_block =
2859 			    yaffs_find_gc_block(dev, aggressive, background);
2860 			dev->gc_chunk = 0;
2861 			dev->n_clean_ups = 0;
2862 		}
2863 
2864 		if (dev->gc_block > 0) {
2865 			dev->all_gcs++;
2866 			if (!aggressive)
2867 				dev->passive_gc_count++;
2868 
2869 			yaffs_trace(YAFFS_TRACE_GC,
2870 				"yaffs: GC n_erased_blocks %d aggressive %d",
2871 				dev->n_erased_blocks, aggressive);
2872 
2873 			gc_ok = yaffs_gc_block(dev, dev->gc_block, aggressive);
2874 		}
2875 
2876 		if (dev->n_erased_blocks < (dev->param.n_reserved_blocks) &&
2877 		    dev->gc_block > 0) {
2878 			yaffs_trace(YAFFS_TRACE_GC,
2879 				"yaffs: GC !!!no reclaim!!! n_erased_blocks %d after try %d block %d",
2880 				dev->n_erased_blocks, max_tries,
2881 				dev->gc_block);
2882 		}
2883 	} while ((dev->n_erased_blocks < dev->param.n_reserved_blocks) &&
2884 		 (dev->gc_block > 0) && (max_tries < 2));
2885 
2886 	return aggressive ? gc_ok : YAFFS_OK;
2887 }
2888 
2889 /*
2890  * yaffs_bg_gc()
2891  * Garbage collects. Intended to be called from a background thread.
2892  * Returns non-zero if at least half the free chunks are erased.
2893  */
yaffs_bg_gc(struct yaffs_dev * dev,unsigned urgency)2894 int yaffs_bg_gc(struct yaffs_dev *dev, unsigned urgency)
2895 {
2896 	int erased_chunks = dev->n_erased_blocks * dev->param.chunks_per_block;
2897 
2898 	yaffs_trace(YAFFS_TRACE_BACKGROUND, "Background gc %u", urgency);
2899 
2900 	yaffs_check_gc(dev, 1);
2901 	return erased_chunks > dev->n_free_chunks / 2;
2902 }
2903 
2904 /*-------------------- Data file manipulation -----------------*/
2905 
yaffs_rd_data_obj(struct yaffs_obj * in,int inode_chunk,u8 * buffer)2906 static int yaffs_rd_data_obj(struct yaffs_obj *in, int inode_chunk, u8 * buffer)
2907 {
2908 	int nand_chunk = yaffs_find_chunk_in_file(in, inode_chunk, NULL);
2909 
2910 	if (nand_chunk >= 0)
2911 		return yaffs_rd_chunk_tags_nand(in->my_dev, nand_chunk,
2912 						buffer, NULL);
2913 	else {
2914 		yaffs_trace(YAFFS_TRACE_NANDACCESS,
2915 			"Chunk %d not found zero instead",
2916 			nand_chunk);
2917 		/* get sane (zero) data if you read a hole */
2918 		memset(buffer, 0, in->my_dev->data_bytes_per_chunk);
2919 		return 0;
2920 	}
2921 
2922 }
2923 
yaffs_chunk_del(struct yaffs_dev * dev,int chunk_id,int mark_flash,int lyn)2924 void yaffs_chunk_del(struct yaffs_dev *dev, int chunk_id, int mark_flash,
2925 		     int lyn)
2926 {
2927 	int block;
2928 	int page;
2929 	struct yaffs_ext_tags tags;
2930 	struct yaffs_block_info *bi;
2931 
2932 	if (chunk_id <= 0)
2933 		return;
2934 
2935 	dev->n_deletions++;
2936 	block = chunk_id / dev->param.chunks_per_block;
2937 	page = chunk_id % dev->param.chunks_per_block;
2938 
2939 	if (!yaffs_check_chunk_bit(dev, block, page))
2940 		yaffs_trace(YAFFS_TRACE_VERIFY,
2941 			"Deleting invalid chunk %d", chunk_id);
2942 
2943 	bi = yaffs_get_block_info(dev, block);
2944 
2945 	yaffs2_update_oldest_dirty_seq(dev, block, bi);
2946 
2947 	yaffs_trace(YAFFS_TRACE_DELETION,
2948 		"line %d delete of chunk %d",
2949 		lyn, chunk_id);
2950 
2951 	if (!dev->param.is_yaffs2 && mark_flash &&
2952 	    bi->block_state != YAFFS_BLOCK_STATE_COLLECTING) {
2953 
2954 		memset(&tags, 0, sizeof(tags));
2955 		tags.is_deleted = 1;
2956 		yaffs_wr_chunk_tags_nand(dev, chunk_id, NULL, &tags);
2957 		yaffs_handle_chunk_update(dev, chunk_id, &tags);
2958 	} else {
2959 		dev->n_unmarked_deletions++;
2960 	}
2961 
2962 	/* Pull out of the management area.
2963 	 * If the whole block became dirty, this will kick off an erasure.
2964 	 */
2965 	if (bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING ||
2966 	    bi->block_state == YAFFS_BLOCK_STATE_FULL ||
2967 	    bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCAN ||
2968 	    bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
2969 		dev->n_free_chunks++;
2970 		yaffs_clear_chunk_bit(dev, block, page);
2971 		bi->pages_in_use--;
2972 
2973 		if (bi->pages_in_use == 0 &&
2974 		    !bi->has_shrink_hdr &&
2975 		    bi->block_state != YAFFS_BLOCK_STATE_ALLOCATING &&
2976 		    bi->block_state != YAFFS_BLOCK_STATE_NEEDS_SCAN) {
2977 			yaffs_block_became_dirty(dev, block);
2978 		}
2979 	}
2980 }
2981 
yaffs_wr_data_obj(struct yaffs_obj * in,int inode_chunk,const u8 * buffer,int n_bytes,int use_reserve)2982 static int yaffs_wr_data_obj(struct yaffs_obj *in, int inode_chunk,
2983 			     const u8 *buffer, int n_bytes, int use_reserve)
2984 {
2985 	/* Find old chunk Need to do this to get serial number
2986 	 * Write new one and patch into tree.
2987 	 * Invalidate old tags.
2988 	 */
2989 
2990 	int prev_chunk_id;
2991 	struct yaffs_ext_tags prev_tags;
2992 	int new_chunk_id;
2993 	struct yaffs_ext_tags new_tags;
2994 	struct yaffs_dev *dev = in->my_dev;
2995 
2996 	yaffs_check_gc(dev, 0);
2997 
2998 	/* Get the previous chunk at this location in the file if it exists.
2999 	 * If it does not exist then put a zero into the tree. This creates
3000 	 * the tnode now, rather than later when it is harder to clean up.
3001 	 */
3002 	prev_chunk_id = yaffs_find_chunk_in_file(in, inode_chunk, &prev_tags);
3003 	if (prev_chunk_id < 1 &&
3004 	    !yaffs_put_chunk_in_file(in, inode_chunk, 0, 0))
3005 		return 0;
3006 
3007 	/* Set up new tags */
3008 	memset(&new_tags, 0, sizeof(new_tags));
3009 
3010 	new_tags.chunk_id = inode_chunk;
3011 	new_tags.obj_id = in->obj_id;
3012 	new_tags.serial_number =
3013 	    (prev_chunk_id > 0) ? prev_tags.serial_number + 1 : 1;
3014 	new_tags.n_bytes = n_bytes;
3015 
3016 	if (n_bytes < 1 || n_bytes > dev->param.total_bytes_per_chunk) {
3017 		yaffs_trace(YAFFS_TRACE_ERROR,
3018 		  "Writing %d bytes to chunk!!!!!!!!!",
3019 		   n_bytes);
3020 		BUG();
3021 	}
3022 
3023 	new_chunk_id =
3024 	    yaffs_write_new_chunk(dev, buffer, &new_tags, use_reserve);
3025 
3026 	if (new_chunk_id > 0) {
3027 		yaffs_put_chunk_in_file(in, inode_chunk, new_chunk_id, 0);
3028 
3029 		if (prev_chunk_id > 0)
3030 			yaffs_chunk_del(dev, prev_chunk_id, 1, __LINE__);
3031 
3032 		yaffs_verify_file_sane(in);
3033 	}
3034 	return new_chunk_id;
3035 
3036 }
3037 
3038 
3039 
yaffs_do_xattrib_mod(struct yaffs_obj * obj,int set,const YCHAR * name,const void * value,int size,int flags)3040 static int yaffs_do_xattrib_mod(struct yaffs_obj *obj, int set,
3041 				const YCHAR *name, const void *value, int size,
3042 				int flags)
3043 {
3044 	struct yaffs_xattr_mod xmod;
3045 	int result;
3046 
3047 	xmod.set = set;
3048 	xmod.name = name;
3049 	xmod.data = value;
3050 	xmod.size = size;
3051 	xmod.flags = flags;
3052 	xmod.result = -ENOSPC;
3053 
3054 	result = yaffs_update_oh(obj, NULL, 0, 0, 0, &xmod);
3055 
3056 	if (result > 0)
3057 		return xmod.result;
3058 	else
3059 		return -ENOSPC;
3060 }
3061 
yaffs_apply_xattrib_mod(struct yaffs_obj * obj,char * buffer,struct yaffs_xattr_mod * xmod)3062 static int yaffs_apply_xattrib_mod(struct yaffs_obj *obj, char *buffer,
3063 				   struct yaffs_xattr_mod *xmod)
3064 {
3065 	int retval = 0;
3066 	int x_offs = sizeof(struct yaffs_obj_hdr);
3067 	struct yaffs_dev *dev = obj->my_dev;
3068 	int x_size = dev->data_bytes_per_chunk - sizeof(struct yaffs_obj_hdr);
3069 	char *x_buffer = buffer + x_offs;
3070 
3071 	if (xmod->set)
3072 		retval =
3073 		    nval_set(x_buffer, x_size, xmod->name, xmod->data,
3074 			     xmod->size, xmod->flags);
3075 	else
3076 		retval = nval_del(x_buffer, x_size, xmod->name);
3077 
3078 	obj->has_xattr = nval_hasvalues(x_buffer, x_size);
3079 	obj->xattr_known = 1;
3080 	xmod->result = retval;
3081 
3082 	return retval;
3083 }
3084 
yaffs_do_xattrib_fetch(struct yaffs_obj * obj,const YCHAR * name,void * value,int size)3085 static int yaffs_do_xattrib_fetch(struct yaffs_obj *obj, const YCHAR *name,
3086 				  void *value, int size)
3087 {
3088 	char *buffer = NULL;
3089 	int result;
3090 	struct yaffs_ext_tags tags;
3091 	struct yaffs_dev *dev = obj->my_dev;
3092 	int x_offs = sizeof(struct yaffs_obj_hdr);
3093 	int x_size = dev->data_bytes_per_chunk - sizeof(struct yaffs_obj_hdr);
3094 	char *x_buffer;
3095 	int retval = 0;
3096 
3097 	if (obj->hdr_chunk < 1)
3098 		return -ENODATA;
3099 
3100 	/* If we know that the object has no xattribs then don't do all the
3101 	 * reading and parsing.
3102 	 */
3103 	if (obj->xattr_known && !obj->has_xattr) {
3104 		if (name)
3105 			return -ENODATA;
3106 		else
3107 			return 0;
3108 	}
3109 
3110 	buffer = (char *)yaffs_get_temp_buffer(dev);
3111 	if (!buffer)
3112 		return -ENOMEM;
3113 
3114 	result =
3115 	    yaffs_rd_chunk_tags_nand(dev, obj->hdr_chunk, (u8 *) buffer, &tags);
3116 
3117 	if (result != YAFFS_OK)
3118 		retval = -ENOENT;
3119 	else {
3120 		x_buffer = buffer + x_offs;
3121 
3122 		if (!obj->xattr_known) {
3123 			obj->has_xattr = nval_hasvalues(x_buffer, x_size);
3124 			obj->xattr_known = 1;
3125 		}
3126 
3127 		if (name)
3128 			retval = nval_get(x_buffer, x_size, name, value, size);
3129 		else
3130 			retval = nval_list(x_buffer, x_size, value, size);
3131 	}
3132 	yaffs_release_temp_buffer(dev, (u8 *) buffer);
3133 	return retval;
3134 }
3135 
yaffs_set_xattrib(struct yaffs_obj * obj,const YCHAR * name,const void * value,int size,int flags)3136 int yaffs_set_xattrib(struct yaffs_obj *obj, const YCHAR * name,
3137 		      const void *value, int size, int flags)
3138 {
3139 	return yaffs_do_xattrib_mod(obj, 1, name, value, size, flags);
3140 }
3141 
yaffs_remove_xattrib(struct yaffs_obj * obj,const YCHAR * name)3142 int yaffs_remove_xattrib(struct yaffs_obj *obj, const YCHAR * name)
3143 {
3144 	return yaffs_do_xattrib_mod(obj, 0, name, NULL, 0, 0);
3145 }
3146 
yaffs_get_xattrib(struct yaffs_obj * obj,const YCHAR * name,void * value,int size)3147 int yaffs_get_xattrib(struct yaffs_obj *obj, const YCHAR * name, void *value,
3148 		      int size)
3149 {
3150 	return yaffs_do_xattrib_fetch(obj, name, value, size);
3151 }
3152 
yaffs_list_xattrib(struct yaffs_obj * obj,char * buffer,int size)3153 int yaffs_list_xattrib(struct yaffs_obj *obj, char *buffer, int size)
3154 {
3155 	return yaffs_do_xattrib_fetch(obj, NULL, buffer, size);
3156 }
3157 
yaffs_check_obj_details_loaded(struct yaffs_obj * in)3158 static void yaffs_check_obj_details_loaded(struct yaffs_obj *in)
3159 {
3160 	u8 *buf;
3161 	struct yaffs_obj_hdr *oh;
3162 	struct yaffs_dev *dev;
3163 	struct yaffs_ext_tags tags;
3164 
3165 	if (!in || !in->lazy_loaded || in->hdr_chunk < 1)
3166 		return;
3167 
3168 	dev = in->my_dev;
3169 	in->lazy_loaded = 0;
3170 	buf = yaffs_get_temp_buffer(dev);
3171 
3172 	yaffs_rd_chunk_tags_nand(dev, in->hdr_chunk, buf, &tags);
3173 	oh = (struct yaffs_obj_hdr *)buf;
3174 
3175 	in->yst_mode = oh->yst_mode;
3176 	yaffs_load_attribs(in, oh);
3177 	yaffs_set_obj_name_from_oh(in, oh);
3178 
3179 	if (in->variant_type == YAFFS_OBJECT_TYPE_SYMLINK) {
3180 		in->variant.symlink_variant.alias =
3181 		    yaffs_clone_str(oh->alias);
3182 	}
3183 	yaffs_release_temp_buffer(dev, buf);
3184 }
3185 
yaffs_load_name_from_oh(struct yaffs_dev * dev,YCHAR * name,const YCHAR * oh_name,int buff_size)3186 static void yaffs_load_name_from_oh(struct yaffs_dev *dev, YCHAR *name,
3187 				    const YCHAR *oh_name, int buff_size)
3188 {
3189 #ifdef CONFIG_YAFFS_AUTO_UNICODE
3190 	if (dev->param.auto_unicode) {
3191 		if (*oh_name) {
3192 			/* It is an ASCII name, do an ASCII to
3193 			 * unicode conversion */
3194 			const char *ascii_oh_name = (const char *)oh_name;
3195 			int n = buff_size - 1;
3196 			while (n > 0 && *ascii_oh_name) {
3197 				*name = *ascii_oh_name;
3198 				name++;
3199 				ascii_oh_name++;
3200 				n--;
3201 			}
3202 		} else {
3203 			yaffs_strncpy(name, oh_name + 1, buff_size - 1);
3204 		}
3205 
3206 		return;
3207 	}
3208 #endif
3209 
3210 	yaffs_strncpy(name, oh_name, buff_size - 1);
3211 }
3212 
yaffs_load_oh_from_name(struct yaffs_dev * dev,YCHAR * oh_name,const YCHAR * name)3213 static void yaffs_load_oh_from_name(struct yaffs_dev *dev, YCHAR *oh_name,
3214 				    const YCHAR *name)
3215 {
3216 #ifdef CONFIG_YAFFS_AUTO_UNICODE
3217 	int is_ascii;
3218 	YCHAR *w;
3219 
3220 	if (dev->param.auto_unicode) {
3221 
3222 		is_ascii = 1;
3223 		w = name;
3224 
3225 		/* Figure out if the name will fit in ascii character set */
3226 		while (is_ascii && *w) {
3227 			if ((*w) & 0xff00)
3228 				is_ascii = 0;
3229 			w++;
3230 		}
3231 
3232 		if (is_ascii) {
3233 			/* It is an ASCII name, so convert unicode to ascii */
3234 			char *ascii_oh_name = (char *)oh_name;
3235 			int n = YAFFS_MAX_NAME_LENGTH - 1;
3236 			while (n > 0 && *name) {
3237 				*ascii_oh_name = *name;
3238 				name++;
3239 				ascii_oh_name++;
3240 				n--;
3241 			}
3242 		} else {
3243 			/* Unicode name, so save starting at the second YCHAR */
3244 			*oh_name = 0;
3245 			yaffs_strncpy(oh_name + 1, name, YAFFS_MAX_NAME_LENGTH - 2);
3246 		}
3247 
3248 		return;
3249 	}
3250 #endif
3251 
3252 	yaffs_strncpy(oh_name, name, YAFFS_MAX_NAME_LENGTH - 1);
3253 }
3254 
3255 /* UpdateObjectHeader updates the header on NAND for an object.
3256  * If name is not NULL, then that new name is used.
3257  */
yaffs_update_oh(struct yaffs_obj * in,const YCHAR * name,int force,int is_shrink,int shadows,struct yaffs_xattr_mod * xmod)3258 int yaffs_update_oh(struct yaffs_obj *in, const YCHAR *name, int force,
3259 		    int is_shrink, int shadows, struct yaffs_xattr_mod *xmod)
3260 {
3261 
3262 	struct yaffs_block_info *bi;
3263 	struct yaffs_dev *dev = in->my_dev;
3264 	int prev_chunk_id;
3265 	int ret_val = 0;
3266 	int new_chunk_id;
3267 	struct yaffs_ext_tags new_tags;
3268 	struct yaffs_ext_tags old_tags;
3269 	const YCHAR *alias = NULL;
3270 	u8 *buffer = NULL;
3271 	YCHAR old_name[YAFFS_MAX_NAME_LENGTH + 1];
3272 	struct yaffs_obj_hdr *oh = NULL;
3273 	loff_t file_size = 0;
3274 
3275 	yaffs_strcpy(old_name, _Y("silly old name"));
3276 
3277 	if (in->fake && in != dev->root_dir && !force && !xmod)
3278 		return ret_val;
3279 
3280 	yaffs_check_gc(dev, 0);
3281 	yaffs_check_obj_details_loaded(in);
3282 
3283 	buffer = yaffs_get_temp_buffer(in->my_dev);
3284 	oh = (struct yaffs_obj_hdr *)buffer;
3285 
3286 	prev_chunk_id = in->hdr_chunk;
3287 
3288 	if (prev_chunk_id > 0) {
3289 		yaffs_rd_chunk_tags_nand(dev, prev_chunk_id,
3290 					  buffer, &old_tags);
3291 
3292 		yaffs_verify_oh(in, oh, &old_tags, 0);
3293 		memcpy(old_name, oh->name, sizeof(oh->name));
3294 		memset(buffer, 0xff, sizeof(struct yaffs_obj_hdr));
3295 	} else {
3296 		memset(buffer, 0xff, dev->data_bytes_per_chunk);
3297 	}
3298 
3299 	oh->type = in->variant_type;
3300 	oh->yst_mode = in->yst_mode;
3301 	oh->shadows_obj = oh->inband_shadowed_obj_id = shadows;
3302 
3303 	yaffs_load_attribs_oh(oh, in);
3304 
3305 	if (in->parent)
3306 		oh->parent_obj_id = in->parent->obj_id;
3307 	else
3308 		oh->parent_obj_id = 0;
3309 
3310 	if (name && *name) {
3311 		memset(oh->name, 0, sizeof(oh->name));
3312 		yaffs_load_oh_from_name(dev, oh->name, name);
3313 	} else if (prev_chunk_id > 0) {
3314 		memcpy(oh->name, old_name, sizeof(oh->name));
3315 	} else {
3316 		memset(oh->name, 0, sizeof(oh->name));
3317 	}
3318 
3319 	oh->is_shrink = is_shrink;
3320 
3321 	switch (in->variant_type) {
3322 	case YAFFS_OBJECT_TYPE_UNKNOWN:
3323 		/* Should not happen */
3324 		break;
3325 	case YAFFS_OBJECT_TYPE_FILE:
3326 		if (oh->parent_obj_id != YAFFS_OBJECTID_DELETED &&
3327 		    oh->parent_obj_id != YAFFS_OBJECTID_UNLINKED)
3328 			file_size = in->variant.file_variant.file_size;
3329 		yaffs_oh_size_load(oh, file_size);
3330 		break;
3331 	case YAFFS_OBJECT_TYPE_HARDLINK:
3332 		oh->equiv_id = in->variant.hardlink_variant.equiv_id;
3333 		break;
3334 	case YAFFS_OBJECT_TYPE_SPECIAL:
3335 		/* Do nothing */
3336 		break;
3337 	case YAFFS_OBJECT_TYPE_DIRECTORY:
3338 		/* Do nothing */
3339 		break;
3340 	case YAFFS_OBJECT_TYPE_SYMLINK:
3341 		alias = in->variant.symlink_variant.alias;
3342 		if (!alias)
3343 			alias = _Y("no alias");
3344 		yaffs_strncpy(oh->alias, alias, YAFFS_MAX_ALIAS_LENGTH);
3345 		oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
3346 		break;
3347 	}
3348 
3349 	/* process any xattrib modifications */
3350 	if (xmod)
3351 		yaffs_apply_xattrib_mod(in, (char *)buffer, xmod);
3352 
3353 	/* Tags */
3354 	memset(&new_tags, 0, sizeof(new_tags));
3355 	in->serial++;
3356 	new_tags.chunk_id = 0;
3357 	new_tags.obj_id = in->obj_id;
3358 	new_tags.serial_number = in->serial;
3359 
3360 	/* Add extra info for file header */
3361 	new_tags.extra_available = 1;
3362 	new_tags.extra_parent_id = oh->parent_obj_id;
3363 	new_tags.extra_file_size = file_size;
3364 	new_tags.extra_is_shrink = oh->is_shrink;
3365 	new_tags.extra_equiv_id = oh->equiv_id;
3366 	new_tags.extra_shadows = (oh->shadows_obj > 0) ? 1 : 0;
3367 	new_tags.extra_obj_type = in->variant_type;
3368 	yaffs_verify_oh(in, oh, &new_tags, 1);
3369 
3370 	/* Create new chunk in NAND */
3371 	new_chunk_id =
3372 	    yaffs_write_new_chunk(dev, buffer, &new_tags,
3373 				  (prev_chunk_id > 0) ? 1 : 0);
3374 
3375 	if (buffer)
3376 		yaffs_release_temp_buffer(dev, buffer);
3377 
3378 	if (new_chunk_id < 0)
3379 		return new_chunk_id;
3380 
3381 	in->hdr_chunk = new_chunk_id;
3382 
3383 	if (prev_chunk_id > 0)
3384 		yaffs_chunk_del(dev, prev_chunk_id, 1, __LINE__);
3385 
3386 	if (!yaffs_obj_cache_dirty(in))
3387 		in->dirty = 0;
3388 
3389 	/* If this was a shrink, then mark the block
3390 	 * that the chunk lives on */
3391 	if (is_shrink) {
3392 		bi = yaffs_get_block_info(in->my_dev,
3393 					  new_chunk_id /
3394 					  in->my_dev->param.chunks_per_block);
3395 		bi->has_shrink_hdr = 1;
3396 	}
3397 
3398 
3399 	return new_chunk_id;
3400 }
3401 
3402 /*--------------------- File read/write ------------------------
3403  * Read and write have very similar structures.
3404  * In general the read/write has three parts to it
3405  * An incomplete chunk to start with (if the read/write is not chunk-aligned)
3406  * Some complete chunks
3407  * An incomplete chunk to end off with
3408  *
3409  * Curve-balls: the first chunk might also be the last chunk.
3410  */
3411 
yaffs_file_rd(struct yaffs_obj * in,u8 * buffer,loff_t offset,int n_bytes)3412 int yaffs_file_rd(struct yaffs_obj *in, u8 * buffer, loff_t offset, int n_bytes)
3413 {
3414 	int chunk;
3415 	u32 start;
3416 	int n_copy;
3417 	int n = n_bytes;
3418 	int n_done = 0;
3419 	struct yaffs_cache *cache;
3420 	struct yaffs_dev *dev;
3421 
3422 	dev = in->my_dev;
3423 
3424 	while (n > 0) {
3425 		yaffs_addr_to_chunk(dev, offset, &chunk, &start);
3426 		chunk++;
3427 
3428 		/* OK now check for the curveball where the start and end are in
3429 		 * the same chunk.
3430 		 */
3431 		if ((start + n) < dev->data_bytes_per_chunk)
3432 			n_copy = n;
3433 		else
3434 			n_copy = dev->data_bytes_per_chunk - start;
3435 
3436 		cache = yaffs_find_chunk_cache(in, chunk);
3437 
3438 		/* If the chunk is already in the cache or it is less than
3439 		 * a whole chunk or we're using inband tags then use the cache
3440 		 * (if there is caching) else bypass the cache.
3441 		 */
3442 		if (cache || n_copy != dev->data_bytes_per_chunk ||
3443 		    dev->param.inband_tags) {
3444 			if (dev->param.n_caches > 0) {
3445 
3446 				/* If we can't find the data in the cache,
3447 				 * then load it up. */
3448 
3449 				if (!cache) {
3450 					cache =
3451 					    yaffs_grab_chunk_cache(in->my_dev);
3452 					cache->object = in;
3453 					cache->chunk_id = chunk;
3454 					cache->dirty = 0;
3455 					cache->locked = 0;
3456 					yaffs_rd_data_obj(in, chunk,
3457 							  cache->data);
3458 					cache->n_bytes = 0;
3459 				}
3460 
3461 				yaffs_use_cache(dev, cache, 0);
3462 
3463 				cache->locked = 1;
3464 
3465 				memcpy(buffer, &cache->data[start], n_copy);
3466 
3467 				cache->locked = 0;
3468 			} else {
3469 				/* Read into the local buffer then copy.. */
3470 
3471 				u8 *local_buffer =
3472 				    yaffs_get_temp_buffer(dev);
3473 				yaffs_rd_data_obj(in, chunk, local_buffer);
3474 
3475 				memcpy(buffer, &local_buffer[start], n_copy);
3476 
3477 				yaffs_release_temp_buffer(dev, local_buffer);
3478 			}
3479 		} else {
3480 			/* A full chunk. Read directly into the buffer. */
3481 			yaffs_rd_data_obj(in, chunk, buffer);
3482 		}
3483 		n -= n_copy;
3484 		offset += n_copy;
3485 		buffer += n_copy;
3486 		n_done += n_copy;
3487 	}
3488 	return n_done;
3489 }
3490 
yaffs_do_file_wr(struct yaffs_obj * in,const u8 * buffer,loff_t offset,int n_bytes,int write_through)3491 int yaffs_do_file_wr(struct yaffs_obj *in, const u8 *buffer, loff_t offset,
3492 		     int n_bytes, int write_through)
3493 {
3494 
3495 	int chunk;
3496 	u32 start;
3497 	int n_copy;
3498 	int n = n_bytes;
3499 	int n_done = 0;
3500 	int n_writeback;
3501 	loff_t start_write = offset;
3502 	int chunk_written = 0;
3503 	u32 n_bytes_read;
3504 	loff_t chunk_start;
3505 	struct yaffs_dev *dev;
3506 
3507 	dev = in->my_dev;
3508 
3509 	while (n > 0 && chunk_written >= 0) {
3510 		yaffs_addr_to_chunk(dev, offset, &chunk, &start);
3511 
3512 		if (((loff_t)chunk) *
3513 		    dev->data_bytes_per_chunk + start != offset ||
3514 		    start >= dev->data_bytes_per_chunk) {
3515 			yaffs_trace(YAFFS_TRACE_ERROR,
3516 				"AddrToChunk of offset %lld gives chunk %d start %d",
3517 				offset, chunk, start);
3518 		}
3519 		chunk++;	/* File pos to chunk in file offset */
3520 
3521 		/* OK now check for the curveball where the start and end are in
3522 		 * the same chunk.
3523 		 */
3524 
3525 		if ((start + n) < dev->data_bytes_per_chunk) {
3526 			n_copy = n;
3527 
3528 			/* Now calculate how many bytes to write back....
3529 			 * If we're overwriting and not writing to then end of
3530 			 * file then we need to write back as much as was there
3531 			 * before.
3532 			 */
3533 
3534 			chunk_start = (((loff_t)(chunk - 1)) *
3535 					dev->data_bytes_per_chunk);
3536 
3537 			if (chunk_start > in->variant.file_variant.file_size)
3538 				n_bytes_read = 0;	/* Past end of file */
3539 			else
3540 				n_bytes_read =
3541 				    in->variant.file_variant.file_size -
3542 				    chunk_start;
3543 
3544 			if (n_bytes_read > dev->data_bytes_per_chunk)
3545 				n_bytes_read = dev->data_bytes_per_chunk;
3546 
3547 			n_writeback =
3548 			    (n_bytes_read >
3549 			     (start + n)) ? n_bytes_read : (start + n);
3550 
3551 			if (n_writeback < 0 ||
3552 			    n_writeback > dev->data_bytes_per_chunk)
3553 				BUG();
3554 
3555 		} else {
3556 			n_copy = dev->data_bytes_per_chunk - start;
3557 			n_writeback = dev->data_bytes_per_chunk;
3558 		}
3559 
3560 		if (n_copy != dev->data_bytes_per_chunk ||
3561 		    dev->param.inband_tags) {
3562 			/* An incomplete start or end chunk (or maybe both
3563 			 * start and end chunk), or we're using inband tags,
3564 			 * so we want to use the cache buffers.
3565 			 */
3566 			if (dev->param.n_caches > 0) {
3567 				struct yaffs_cache *cache;
3568 
3569 				/* If we can't find the data in the cache, then
3570 				 * load the cache */
3571 				cache = yaffs_find_chunk_cache(in, chunk);
3572 
3573 				if (!cache &&
3574 				    yaffs_check_alloc_available(dev, 1)) {
3575 					cache = yaffs_grab_chunk_cache(dev);
3576 					cache->object = in;
3577 					cache->chunk_id = chunk;
3578 					cache->dirty = 0;
3579 					cache->locked = 0;
3580 					yaffs_rd_data_obj(in, chunk,
3581 							  cache->data);
3582 				} else if (cache &&
3583 					   !cache->dirty &&
3584 					   !yaffs_check_alloc_available(dev,
3585 									1)) {
3586 					/* Drop the cache if it was a read cache
3587 					 * item and no space check has been made
3588 					 * for it.
3589 					 */
3590 					cache = NULL;
3591 				}
3592 
3593 				if (cache) {
3594 					yaffs_use_cache(dev, cache, 1);
3595 					cache->locked = 1;
3596 
3597 					memcpy(&cache->data[start], buffer,
3598 					       n_copy);
3599 
3600 					cache->locked = 0;
3601 					cache->n_bytes = n_writeback;
3602 
3603 					if (write_through) {
3604 						chunk_written =
3605 						    yaffs_wr_data_obj
3606 						    (cache->object,
3607 						     cache->chunk_id,
3608 						     cache->data,
3609 						     cache->n_bytes, 1);
3610 						cache->dirty = 0;
3611 					}
3612 				} else {
3613 					chunk_written = -1;	/* fail write */
3614 				}
3615 			} else {
3616 				/* An incomplete start or end chunk (or maybe
3617 				 * both start and end chunk). Read into the
3618 				 * local buffer then copy over and write back.
3619 				 */
3620 
3621 				u8 *local_buffer = yaffs_get_temp_buffer(dev);
3622 
3623 				yaffs_rd_data_obj(in, chunk, local_buffer);
3624 				memcpy(&local_buffer[start], buffer, n_copy);
3625 
3626 				chunk_written =
3627 				    yaffs_wr_data_obj(in, chunk,
3628 						      local_buffer,
3629 						      n_writeback, 0);
3630 
3631 				yaffs_release_temp_buffer(dev, local_buffer);
3632 			}
3633 		} else {
3634 			/* A full chunk. Write directly from the buffer. */
3635 
3636 			chunk_written =
3637 			    yaffs_wr_data_obj(in, chunk, buffer,
3638 					      dev->data_bytes_per_chunk, 0);
3639 
3640 			/* Since we've overwritten the cached data,
3641 			 * we better invalidate it. */
3642 			yaffs_invalidate_chunk_cache(in, chunk);
3643 		}
3644 
3645 		if (chunk_written >= 0) {
3646 			n -= n_copy;
3647 			offset += n_copy;
3648 			buffer += n_copy;
3649 			n_done += n_copy;
3650 		}
3651 	}
3652 
3653 	/* Update file object */
3654 
3655 	if ((start_write + n_done) > in->variant.file_variant.file_size)
3656 		in->variant.file_variant.file_size = (start_write + n_done);
3657 
3658 	in->dirty = 1;
3659 	return n_done;
3660 }
3661 
yaffs_wr_file(struct yaffs_obj * in,const u8 * buffer,loff_t offset,int n_bytes,int write_through)3662 int yaffs_wr_file(struct yaffs_obj *in, const u8 *buffer, loff_t offset,
3663 		  int n_bytes, int write_through)
3664 {
3665 	yaffs2_handle_hole(in, offset);
3666 	return yaffs_do_file_wr(in, buffer, offset, n_bytes, write_through);
3667 }
3668 
3669 /* ---------------------- File resizing stuff ------------------ */
3670 
yaffs_prune_chunks(struct yaffs_obj * in,loff_t new_size)3671 static void yaffs_prune_chunks(struct yaffs_obj *in, loff_t new_size)
3672 {
3673 
3674 	struct yaffs_dev *dev = in->my_dev;
3675 	loff_t old_size = in->variant.file_variant.file_size;
3676 	int i;
3677 	int chunk_id;
3678 	u32 dummy;
3679 	int last_del;
3680 	int start_del;
3681 
3682 	if (old_size > 0)
3683 		yaffs_addr_to_chunk(dev, old_size - 1, &last_del, &dummy);
3684 	else
3685 		last_del = 0;
3686 
3687 	yaffs_addr_to_chunk(dev, new_size + dev->data_bytes_per_chunk - 1,
3688 				&start_del, &dummy);
3689 	last_del++;
3690 	start_del++;
3691 
3692 	/* Delete backwards so that we don't end up with holes if
3693 	 * power is lost part-way through the operation.
3694 	 */
3695 	for (i = last_del; i >= start_del; i--) {
3696 		/* NB this could be optimised somewhat,
3697 		 * eg. could retrieve the tags and write them without
3698 		 * using yaffs_chunk_del
3699 		 */
3700 
3701 		chunk_id = yaffs_find_del_file_chunk(in, i, NULL);
3702 
3703 		if (chunk_id < 1)
3704 			continue;
3705 
3706 		if (chunk_id <
3707 		    (dev->internal_start_block * dev->param.chunks_per_block) ||
3708 		    chunk_id >=
3709 		    ((dev->internal_end_block + 1) *
3710 		      dev->param.chunks_per_block)) {
3711 			yaffs_trace(YAFFS_TRACE_ALWAYS,
3712 				"Found daft chunk_id %d for %d",
3713 				chunk_id, i);
3714 		} else {
3715 			in->n_data_chunks--;
3716 			yaffs_chunk_del(dev, chunk_id, 1, __LINE__);
3717 		}
3718 	}
3719 }
3720 
yaffs_resize_file_down(struct yaffs_obj * obj,loff_t new_size)3721 void yaffs_resize_file_down(struct yaffs_obj *obj, loff_t new_size)
3722 {
3723 	int new_full;
3724 	u32 new_partial;
3725 	struct yaffs_dev *dev = obj->my_dev;
3726 
3727 	yaffs_addr_to_chunk(dev, new_size, &new_full, &new_partial);
3728 
3729 	yaffs_prune_chunks(obj, new_size);
3730 
3731 	if (new_partial != 0) {
3732 		int last_chunk = 1 + new_full;
3733 		u8 *local_buffer = yaffs_get_temp_buffer(dev);
3734 
3735 		/* Rewrite the last chunk with its new size and zero pad */
3736 		yaffs_rd_data_obj(obj, last_chunk, local_buffer);
3737 		memset(local_buffer + new_partial, 0,
3738 		       dev->data_bytes_per_chunk - new_partial);
3739 
3740 		yaffs_wr_data_obj(obj, last_chunk, local_buffer,
3741 				  new_partial, 1);
3742 
3743 		yaffs_release_temp_buffer(dev, local_buffer);
3744 	}
3745 
3746 	obj->variant.file_variant.file_size = new_size;
3747 
3748 	yaffs_prune_tree(dev, &obj->variant.file_variant);
3749 }
3750 
yaffs_resize_file(struct yaffs_obj * in,loff_t new_size)3751 int yaffs_resize_file(struct yaffs_obj *in, loff_t new_size)
3752 {
3753 	struct yaffs_dev *dev = in->my_dev;
3754 	loff_t old_size = in->variant.file_variant.file_size;
3755 
3756 	yaffs_flush_file_cache(in);
3757 	yaffs_invalidate_whole_cache(in);
3758 
3759 	yaffs_check_gc(dev, 0);
3760 
3761 	if (in->variant_type != YAFFS_OBJECT_TYPE_FILE)
3762 		return YAFFS_FAIL;
3763 
3764 	if (new_size == old_size)
3765 		return YAFFS_OK;
3766 
3767 	if (new_size > old_size) {
3768 		yaffs2_handle_hole(in, new_size);
3769 		in->variant.file_variant.file_size = new_size;
3770 	} else {
3771 		/* new_size < old_size */
3772 		yaffs_resize_file_down(in, new_size);
3773 	}
3774 
3775 	/* Write a new object header to reflect the resize.
3776 	 * show we've shrunk the file, if need be
3777 	 * Do this only if the file is not in the deleted directories
3778 	 * and is not shadowed.
3779 	 */
3780 	if (in->parent &&
3781 	    !in->is_shadowed &&
3782 	    in->parent->obj_id != YAFFS_OBJECTID_UNLINKED &&
3783 	    in->parent->obj_id != YAFFS_OBJECTID_DELETED)
3784 		yaffs_update_oh(in, NULL, 0, 0, 0, NULL);
3785 
3786 	return YAFFS_OK;
3787 }
3788 
yaffs_flush_file(struct yaffs_obj * in,int update_time,int data_sync)3789 int yaffs_flush_file(struct yaffs_obj *in, int update_time, int data_sync)
3790 {
3791 	if (!in->dirty)
3792 		return YAFFS_OK;
3793 
3794 	yaffs_flush_file_cache(in);
3795 
3796 	if (data_sync)
3797 		return YAFFS_OK;
3798 
3799 	if (update_time)
3800 		yaffs_load_current_time(in, 0, 0);
3801 
3802 	return (yaffs_update_oh(in, NULL, 0, 0, 0, NULL) >= 0) ?
3803 				YAFFS_OK : YAFFS_FAIL;
3804 }
3805 
3806 
3807 /* yaffs_del_file deletes the whole file data
3808  * and the inode associated with the file.
3809  * It does not delete the links associated with the file.
3810  */
yaffs_unlink_file_if_needed(struct yaffs_obj * in)3811 static int yaffs_unlink_file_if_needed(struct yaffs_obj *in)
3812 {
3813 	int ret_val;
3814 	int del_now = 0;
3815 	struct yaffs_dev *dev = in->my_dev;
3816 
3817 	if (!in->my_inode)
3818 		del_now = 1;
3819 
3820 	if (del_now) {
3821 		ret_val =
3822 		    yaffs_change_obj_name(in, in->my_dev->del_dir,
3823 					  _Y("deleted"), 0, 0);
3824 		yaffs_trace(YAFFS_TRACE_TRACING,
3825 			"yaffs: immediate deletion of file %d",
3826 			in->obj_id);
3827 		in->deleted = 1;
3828 		in->my_dev->n_deleted_files++;
3829 		if (dev->param.disable_soft_del || dev->param.is_yaffs2)
3830 			yaffs_resize_file(in, 0);
3831 		yaffs_soft_del_file(in);
3832 	} else {
3833 		ret_val =
3834 		    yaffs_change_obj_name(in, in->my_dev->unlinked_dir,
3835 					  _Y("unlinked"), 0, 0);
3836 	}
3837 	return ret_val;
3838 }
3839 
yaffs_del_file(struct yaffs_obj * in)3840 int yaffs_del_file(struct yaffs_obj *in)
3841 {
3842 	int ret_val = YAFFS_OK;
3843 	int deleted;	/* Need to cache value on stack if in is freed */
3844 	struct yaffs_dev *dev = in->my_dev;
3845 
3846 	if (dev->param.disable_soft_del || dev->param.is_yaffs2)
3847 		yaffs_resize_file(in, 0);
3848 
3849 	if (in->n_data_chunks > 0) {
3850 		/* Use soft deletion if there is data in the file.
3851 		 * That won't be the case if it has been resized to zero.
3852 		 */
3853 		if (!in->unlinked)
3854 			ret_val = yaffs_unlink_file_if_needed(in);
3855 
3856 		deleted = in->deleted;
3857 
3858 		if (ret_val == YAFFS_OK && in->unlinked && !in->deleted) {
3859 			in->deleted = 1;
3860 			deleted = 1;
3861 			in->my_dev->n_deleted_files++;
3862 			yaffs_soft_del_file(in);
3863 		}
3864 		return deleted ? YAFFS_OK : YAFFS_FAIL;
3865 	} else {
3866 		/* The file has no data chunks so we toss it immediately */
3867 		yaffs_free_tnode(in->my_dev, in->variant.file_variant.top);
3868 		in->variant.file_variant.top = NULL;
3869 		yaffs_generic_obj_del(in);
3870 
3871 		return YAFFS_OK;
3872 	}
3873 }
3874 
yaffs_is_non_empty_dir(struct yaffs_obj * obj)3875 int yaffs_is_non_empty_dir(struct yaffs_obj *obj)
3876 {
3877 	return (obj &&
3878 		obj->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY) &&
3879 		!(list_empty(&obj->variant.dir_variant.children));
3880 }
3881 
yaffs_del_dir(struct yaffs_obj * obj)3882 static int yaffs_del_dir(struct yaffs_obj *obj)
3883 {
3884 	/* First check that the directory is empty. */
3885 	if (yaffs_is_non_empty_dir(obj))
3886 		return YAFFS_FAIL;
3887 
3888 	return yaffs_generic_obj_del(obj);
3889 }
3890 
yaffs_del_symlink(struct yaffs_obj * in)3891 static int yaffs_del_symlink(struct yaffs_obj *in)
3892 {
3893 	kfree(in->variant.symlink_variant.alias);
3894 	in->variant.symlink_variant.alias = NULL;
3895 
3896 	return yaffs_generic_obj_del(in);
3897 }
3898 
yaffs_del_link(struct yaffs_obj * in)3899 static int yaffs_del_link(struct yaffs_obj *in)
3900 {
3901 	/* remove this hardlink from the list associated with the equivalent
3902 	 * object
3903 	 */
3904 	list_del_init(&in->hard_links);
3905 	return yaffs_generic_obj_del(in);
3906 }
3907 
yaffs_del_obj(struct yaffs_obj * obj)3908 int yaffs_del_obj(struct yaffs_obj *obj)
3909 {
3910 	int ret_val = -1;
3911 
3912 	switch (obj->variant_type) {
3913 	case YAFFS_OBJECT_TYPE_FILE:
3914 		ret_val = yaffs_del_file(obj);
3915 		break;
3916 	case YAFFS_OBJECT_TYPE_DIRECTORY:
3917 		if (!list_empty(&obj->variant.dir_variant.dirty)) {
3918 			yaffs_trace(YAFFS_TRACE_BACKGROUND,
3919 				"Remove object %d from dirty directories",
3920 				obj->obj_id);
3921 			list_del_init(&obj->variant.dir_variant.dirty);
3922 		}
3923 		return yaffs_del_dir(obj);
3924 		break;
3925 	case YAFFS_OBJECT_TYPE_SYMLINK:
3926 		ret_val = yaffs_del_symlink(obj);
3927 		break;
3928 	case YAFFS_OBJECT_TYPE_HARDLINK:
3929 		ret_val = yaffs_del_link(obj);
3930 		break;
3931 	case YAFFS_OBJECT_TYPE_SPECIAL:
3932 		ret_val = yaffs_generic_obj_del(obj);
3933 		break;
3934 	case YAFFS_OBJECT_TYPE_UNKNOWN:
3935 		ret_val = 0;
3936 		break;		/* should not happen. */
3937 	}
3938 	return ret_val;
3939 }
3940 
yaffs_unlink_worker(struct yaffs_obj * obj)3941 static int yaffs_unlink_worker(struct yaffs_obj *obj)
3942 {
3943 	int del_now = 0;
3944 
3945 	if (!obj)
3946 		return YAFFS_FAIL;
3947 
3948 	if (!obj->my_inode)
3949 		del_now = 1;
3950 
3951 	yaffs_update_parent(obj->parent);
3952 
3953 	if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) {
3954 		return yaffs_del_link(obj);
3955 	} else if (!list_empty(&obj->hard_links)) {
3956 		/* Curve ball: We're unlinking an object that has a hardlink.
3957 		 *
3958 		 * This problem arises because we are not strictly following
3959 		 * The Linux link/inode model.
3960 		 *
3961 		 * We can't really delete the object.
3962 		 * Instead, we do the following:
3963 		 * - Select a hardlink.
3964 		 * - Unhook it from the hard links
3965 		 * - Move it from its parent directory so that the rename works.
3966 		 * - Rename the object to the hardlink's name.
3967 		 * - Delete the hardlink
3968 		 */
3969 
3970 		struct yaffs_obj *hl;
3971 		struct yaffs_obj *parent;
3972 		int ret_val;
3973 		YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
3974 
3975 		hl = list_entry(obj->hard_links.next, struct yaffs_obj,
3976 				hard_links);
3977 
3978 		yaffs_get_obj_name(hl, name, YAFFS_MAX_NAME_LENGTH + 1);
3979 		parent = hl->parent;
3980 
3981 		list_del_init(&hl->hard_links);
3982 
3983 		yaffs_add_obj_to_dir(obj->my_dev->unlinked_dir, hl);
3984 
3985 		ret_val = yaffs_change_obj_name(obj, parent, name, 0, 0);
3986 
3987 		if (ret_val == YAFFS_OK)
3988 			ret_val = yaffs_generic_obj_del(hl);
3989 
3990 		return ret_val;
3991 
3992 	} else if (del_now) {
3993 		switch (obj->variant_type) {
3994 		case YAFFS_OBJECT_TYPE_FILE:
3995 			return yaffs_del_file(obj);
3996 			break;
3997 		case YAFFS_OBJECT_TYPE_DIRECTORY:
3998 			list_del_init(&obj->variant.dir_variant.dirty);
3999 			return yaffs_del_dir(obj);
4000 			break;
4001 		case YAFFS_OBJECT_TYPE_SYMLINK:
4002 			return yaffs_del_symlink(obj);
4003 			break;
4004 		case YAFFS_OBJECT_TYPE_SPECIAL:
4005 			return yaffs_generic_obj_del(obj);
4006 			break;
4007 		case YAFFS_OBJECT_TYPE_HARDLINK:
4008 		case YAFFS_OBJECT_TYPE_UNKNOWN:
4009 		default:
4010 			return YAFFS_FAIL;
4011 		}
4012 	} else if (yaffs_is_non_empty_dir(obj)) {
4013 		return YAFFS_FAIL;
4014 	} else {
4015 		return yaffs_change_obj_name(obj, obj->my_dev->unlinked_dir,
4016 						_Y("unlinked"), 0, 0);
4017 	}
4018 }
4019 
yaffs_unlink_obj(struct yaffs_obj * obj)4020 static int yaffs_unlink_obj(struct yaffs_obj *obj)
4021 {
4022 	if (obj && obj->unlink_allowed)
4023 		return yaffs_unlink_worker(obj);
4024 
4025 	return YAFFS_FAIL;
4026 }
4027 
yaffs_unlinker(struct yaffs_obj * dir,const YCHAR * name)4028 int yaffs_unlinker(struct yaffs_obj *dir, const YCHAR *name)
4029 {
4030 	struct yaffs_obj *obj;
4031 
4032 	obj = yaffs_find_by_name(dir, name);
4033 	return yaffs_unlink_obj(obj);
4034 }
4035 
4036 /* Note:
4037  * If old_name is NULL then we take old_dir as the object to be renamed.
4038  */
yaffs_rename_obj(struct yaffs_obj * old_dir,const YCHAR * old_name,struct yaffs_obj * new_dir,const YCHAR * new_name)4039 int yaffs_rename_obj(struct yaffs_obj *old_dir, const YCHAR *old_name,
4040 		     struct yaffs_obj *new_dir, const YCHAR *new_name)
4041 {
4042 	struct yaffs_obj *obj = NULL;
4043 	struct yaffs_obj *existing_target = NULL;
4044 	int force = 0;
4045 	int result;
4046 	struct yaffs_dev *dev;
4047 
4048 	if (!old_dir || old_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
4049 		BUG();
4050 		return YAFFS_FAIL;
4051 	}
4052 	if (!new_dir || new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
4053 		BUG();
4054 		return YAFFS_FAIL;
4055 	}
4056 
4057 	dev = old_dir->my_dev;
4058 
4059 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
4060 	/* Special case for case insemsitive systems.
4061 	 * While look-up is case insensitive, the name isn't.
4062 	 * Therefore we might want to change x.txt to X.txt
4063 	 */
4064 	if (old_dir == new_dir &&
4065 		old_name && new_name &&
4066 		yaffs_strcmp(old_name, new_name) == 0)
4067 		force = 1;
4068 #endif
4069 
4070 	if (yaffs_strnlen(new_name, YAFFS_MAX_NAME_LENGTH + 1) >
4071 	    YAFFS_MAX_NAME_LENGTH)
4072 		/* ENAMETOOLONG */
4073 		return YAFFS_FAIL;
4074 
4075 	if (old_name)
4076 		obj = yaffs_find_by_name(old_dir, old_name);
4077 	else{
4078 		obj = old_dir;
4079 		old_dir = obj->parent;
4080 	}
4081 
4082 	if (obj && obj->rename_allowed) {
4083 		/* Now handle an existing target, if there is one */
4084 		existing_target = yaffs_find_by_name(new_dir, new_name);
4085 		if (yaffs_is_non_empty_dir(existing_target)) {
4086 			return YAFFS_FAIL;	/* ENOTEMPTY */
4087 		} else if (existing_target && existing_target != obj) {
4088 			/* Nuke the target first, using shadowing,
4089 			 * but only if it isn't the same object.
4090 			 *
4091 			 * Note we must disable gc here otherwise it can mess
4092 			 * up the shadowing.
4093 			 *
4094 			 */
4095 			dev->gc_disable = 1;
4096 			yaffs_change_obj_name(obj, new_dir, new_name, force,
4097 					      existing_target->obj_id);
4098 			existing_target->is_shadowed = 1;
4099 			yaffs_unlink_obj(existing_target);
4100 			dev->gc_disable = 0;
4101 		}
4102 
4103 		result = yaffs_change_obj_name(obj, new_dir, new_name, 1, 0);
4104 
4105 		yaffs_update_parent(old_dir);
4106 		if (new_dir != old_dir)
4107 			yaffs_update_parent(new_dir);
4108 
4109 		return result;
4110 	}
4111 	return YAFFS_FAIL;
4112 }
4113 
4114 /*----------------------- Initialisation Scanning ---------------------- */
4115 
yaffs_handle_shadowed_obj(struct yaffs_dev * dev,int obj_id,int backward_scanning)4116 void yaffs_handle_shadowed_obj(struct yaffs_dev *dev, int obj_id,
4117 			       int backward_scanning)
4118 {
4119 	struct yaffs_obj *obj;
4120 
4121 	if (backward_scanning) {
4122 		/* Handle YAFFS2 case (backward scanning)
4123 		 * If the shadowed object exists then ignore.
4124 		 */
4125 		obj = yaffs_find_by_number(dev, obj_id);
4126 		if (obj)
4127 			return;
4128 	}
4129 
4130 	/* Let's create it (if it does not exist) assuming it is a file so that
4131 	 * it can do shrinking etc.
4132 	 * We put it in unlinked dir to be cleaned up after the scanning
4133 	 */
4134 	obj =
4135 	    yaffs_find_or_create_by_number(dev, obj_id, YAFFS_OBJECT_TYPE_FILE);
4136 	if (!obj)
4137 		return;
4138 	obj->is_shadowed = 1;
4139 	yaffs_add_obj_to_dir(dev->unlinked_dir, obj);
4140 	obj->variant.file_variant.shrink_size = 0;
4141 	obj->valid = 1;		/* So that we don't read any other info. */
4142 }
4143 
yaffs_link_fixup(struct yaffs_dev * dev,struct list_head * hard_list)4144 void yaffs_link_fixup(struct yaffs_dev *dev, struct list_head *hard_list)
4145 {
4146 	struct list_head *lh;
4147 	struct list_head *save;
4148 	struct yaffs_obj *hl;
4149 	struct yaffs_obj *in;
4150 
4151 	list_for_each_safe(lh, save, hard_list) {
4152 		hl = list_entry(lh, struct yaffs_obj, hard_links);
4153 		in = yaffs_find_by_number(dev,
4154 					hl->variant.hardlink_variant.equiv_id);
4155 
4156 		if (in) {
4157 			/* Add the hardlink pointers */
4158 			hl->variant.hardlink_variant.equiv_obj = in;
4159 			list_add(&hl->hard_links, &in->hard_links);
4160 		} else {
4161 			/* Todo Need to report/handle this better.
4162 			 * Got a problem... hardlink to a non-existant object
4163 			 */
4164 			hl->variant.hardlink_variant.equiv_obj = NULL;
4165 			INIT_LIST_HEAD(&hl->hard_links);
4166 		}
4167 	}
4168 }
4169 
yaffs_strip_deleted_objs(struct yaffs_dev * dev)4170 static void yaffs_strip_deleted_objs(struct yaffs_dev *dev)
4171 {
4172 	/*
4173 	 *  Sort out state of unlinked and deleted objects after scanning.
4174 	 */
4175 	struct list_head *i;
4176 	struct list_head *n;
4177 	struct yaffs_obj *l;
4178 
4179 	if (dev->read_only)
4180 		return;
4181 
4182 	/* Soft delete all the unlinked files */
4183 	list_for_each_safe(i, n,
4184 			   &dev->unlinked_dir->variant.dir_variant.children) {
4185 		l = list_entry(i, struct yaffs_obj, siblings);
4186 		yaffs_del_obj(l);
4187 	}
4188 
4189 	list_for_each_safe(i, n, &dev->del_dir->variant.dir_variant.children) {
4190 		l = list_entry(i, struct yaffs_obj, siblings);
4191 		yaffs_del_obj(l);
4192 	}
4193 }
4194 
4195 /*
4196  * This code iterates through all the objects making sure that they are rooted.
4197  * Any unrooted objects are re-rooted in lost+found.
4198  * An object needs to be in one of:
4199  * - Directly under deleted, unlinked
4200  * - Directly or indirectly under root.
4201  *
4202  * Note:
4203  *  This code assumes that we don't ever change the current relationships
4204  *  between directories:
4205  *   root_dir->parent == unlinked_dir->parent == del_dir->parent == NULL
4206  *   lost-n-found->parent == root_dir
4207  *
4208  * This fixes the problem where directories might have inadvertently been
4209  * deleted leaving the object "hanging" without being rooted in the
4210  * directory tree.
4211  */
4212 
yaffs_has_null_parent(struct yaffs_dev * dev,struct yaffs_obj * obj)4213 static int yaffs_has_null_parent(struct yaffs_dev *dev, struct yaffs_obj *obj)
4214 {
4215 	return (obj == dev->del_dir ||
4216 		obj == dev->unlinked_dir || obj == dev->root_dir);
4217 }
4218 
yaffs_fix_hanging_objs(struct yaffs_dev * dev)4219 static void yaffs_fix_hanging_objs(struct yaffs_dev *dev)
4220 {
4221 	struct yaffs_obj *obj;
4222 	struct yaffs_obj *parent;
4223 	int i;
4224 	struct list_head *lh;
4225 	struct list_head *n;
4226 	int depth_limit;
4227 	int hanging;
4228 
4229 	if (dev->read_only)
4230 		return;
4231 
4232 	/* Iterate through the objects in each hash entry,
4233 	 * looking at each object.
4234 	 * Make sure it is rooted.
4235 	 */
4236 
4237 	for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
4238 		list_for_each_safe(lh, n, &dev->obj_bucket[i].list) {
4239 			obj = list_entry(lh, struct yaffs_obj, hash_link);
4240 			parent = obj->parent;
4241 
4242 			if (yaffs_has_null_parent(dev, obj)) {
4243 				/* These directories are not hanging */
4244 				hanging = 0;
4245 			} else if (!parent ||
4246 				   parent->variant_type !=
4247 				   YAFFS_OBJECT_TYPE_DIRECTORY) {
4248 				hanging = 1;
4249 			} else if (yaffs_has_null_parent(dev, parent)) {
4250 				hanging = 0;
4251 			} else {
4252 				/*
4253 				 * Need to follow the parent chain to
4254 				 * see if it is hanging.
4255 				 */
4256 				hanging = 0;
4257 				depth_limit = 100;
4258 
4259 				while (parent != dev->root_dir &&
4260 				       parent->parent &&
4261 				       parent->parent->variant_type ==
4262 				       YAFFS_OBJECT_TYPE_DIRECTORY &&
4263 				       depth_limit > 0) {
4264 					parent = parent->parent;
4265 					depth_limit--;
4266 				}
4267 				if (parent != dev->root_dir)
4268 					hanging = 1;
4269 			}
4270 			if (hanging) {
4271 				yaffs_trace(YAFFS_TRACE_SCAN,
4272 					"Hanging object %d moved to lost and found",
4273 					obj->obj_id);
4274 				yaffs_add_obj_to_dir(dev->lost_n_found, obj);
4275 			}
4276 		}
4277 	}
4278 }
4279 
4280 /*
4281  * Delete directory contents for cleaning up lost and found.
4282  */
yaffs_del_dir_contents(struct yaffs_obj * dir)4283 static void yaffs_del_dir_contents(struct yaffs_obj *dir)
4284 {
4285 	struct yaffs_obj *obj;
4286 	struct list_head *lh;
4287 	struct list_head *n;
4288 
4289 	if (dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
4290 		BUG();
4291 
4292 	list_for_each_safe(lh, n, &dir->variant.dir_variant.children) {
4293 		obj = list_entry(lh, struct yaffs_obj, siblings);
4294 		if (obj->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY)
4295 			yaffs_del_dir_contents(obj);
4296 		yaffs_trace(YAFFS_TRACE_SCAN,
4297 			"Deleting lost_found object %d",
4298 			obj->obj_id);
4299 		yaffs_unlink_obj(obj);
4300 	}
4301 }
4302 
yaffs_empty_l_n_f(struct yaffs_dev * dev)4303 static void yaffs_empty_l_n_f(struct yaffs_dev *dev)
4304 {
4305 	yaffs_del_dir_contents(dev->lost_n_found);
4306 }
4307 
4308 
yaffs_find_by_name(struct yaffs_obj * directory,const YCHAR * name)4309 struct yaffs_obj *yaffs_find_by_name(struct yaffs_obj *directory,
4310 				     const YCHAR *name)
4311 {
4312 	int sum;
4313 	struct list_head *i;
4314 	YCHAR buffer[YAFFS_MAX_NAME_LENGTH + 1];
4315 	struct yaffs_obj *l;
4316 
4317 	if (!name)
4318 		return NULL;
4319 
4320 	if (!directory) {
4321 		yaffs_trace(YAFFS_TRACE_ALWAYS,
4322 			"tragedy: yaffs_find_by_name: null pointer directory"
4323 			);
4324 		BUG();
4325 		return NULL;
4326 	}
4327 	if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
4328 		yaffs_trace(YAFFS_TRACE_ALWAYS,
4329 			"tragedy: yaffs_find_by_name: non-directory"
4330 			);
4331 		BUG();
4332 	}
4333 
4334 	sum = yaffs_calc_name_sum(name);
4335 
4336 	list_for_each(i, &directory->variant.dir_variant.children) {
4337 		l = list_entry(i, struct yaffs_obj, siblings);
4338 
4339 		if (l->parent != directory)
4340 			BUG();
4341 
4342 		yaffs_check_obj_details_loaded(l);
4343 
4344 		/* Special case for lost-n-found */
4345 		if (l->obj_id == YAFFS_OBJECTID_LOSTNFOUND) {
4346 			if (!yaffs_strcmp(name, YAFFS_LOSTNFOUND_NAME))
4347 				return l;
4348 		} else if (l->sum == sum || l->hdr_chunk <= 0) {
4349 			/* LostnFound chunk called Objxxx
4350 			 * Do a real check
4351 			 */
4352 			yaffs_get_obj_name(l, buffer,
4353 				YAFFS_MAX_NAME_LENGTH + 1);
4354 			if (!yaffs_strncmp(name, buffer, YAFFS_MAX_NAME_LENGTH))
4355 				return l;
4356 		}
4357 	}
4358 	return NULL;
4359 }
4360 
4361 /* GetEquivalentObject dereferences any hard links to get to the
4362  * actual object.
4363  */
4364 
yaffs_get_equivalent_obj(struct yaffs_obj * obj)4365 struct yaffs_obj *yaffs_get_equivalent_obj(struct yaffs_obj *obj)
4366 {
4367 	if (obj && obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) {
4368 		obj = obj->variant.hardlink_variant.equiv_obj;
4369 		yaffs_check_obj_details_loaded(obj);
4370 	}
4371 	return obj;
4372 }
4373 
4374 /*
4375  *  A note or two on object names.
4376  *  * If the object name is missing, we then make one up in the form objnnn
4377  *
4378  *  * ASCII names are stored in the object header's name field from byte zero
4379  *  * Unicode names are historically stored starting from byte zero.
4380  *
4381  * Then there are automatic Unicode names...
4382  * The purpose of these is to save names in a way that can be read as
4383  * ASCII or Unicode names as appropriate, thus allowing a Unicode and ASCII
4384  * system to share files.
4385  *
4386  * These automatic unicode are stored slightly differently...
4387  *  - If the name can fit in the ASCII character space then they are saved as
4388  *    ascii names as per above.
4389  *  - If the name needs Unicode then the name is saved in Unicode
4390  *    starting at oh->name[1].
4391 
4392  */
yaffs_fix_null_name(struct yaffs_obj * obj,YCHAR * name,int buffer_size)4393 static void yaffs_fix_null_name(struct yaffs_obj *obj, YCHAR *name,
4394 				int buffer_size)
4395 {
4396 	/* Create an object name if we could not find one. */
4397 	if (yaffs_strnlen(name, YAFFS_MAX_NAME_LENGTH) == 0) {
4398 		YCHAR local_name[20];
4399 		YCHAR num_string[20];
4400 		YCHAR *x = &num_string[19];
4401 		unsigned v = obj->obj_id;
4402 		num_string[19] = 0;
4403 		while (v > 0) {
4404 			x--;
4405 			*x = '0' + (v % 10);
4406 			v /= 10;
4407 		}
4408 		/* make up a name */
4409 		yaffs_strcpy(local_name, YAFFS_LOSTNFOUND_PREFIX);
4410 		yaffs_strcat(local_name, x);
4411 		yaffs_strncpy(name, local_name, buffer_size - 1);
4412 	}
4413 }
4414 
yaffs_get_obj_name(struct yaffs_obj * obj,YCHAR * name,int buffer_size)4415 int yaffs_get_obj_name(struct yaffs_obj *obj, YCHAR *name, int buffer_size)
4416 {
4417 	memset(name, 0, buffer_size * sizeof(YCHAR));
4418 	yaffs_check_obj_details_loaded(obj);
4419 	if (obj->obj_id == YAFFS_OBJECTID_LOSTNFOUND) {
4420 		yaffs_strncpy(name, YAFFS_LOSTNFOUND_NAME, buffer_size - 1);
4421 	} else if (obj->short_name[0]) {
4422 		yaffs_strcpy(name, obj->short_name);
4423 	} else if (obj->hdr_chunk > 0) {
4424 		u8 *buffer = yaffs_get_temp_buffer(obj->my_dev);
4425 
4426 		struct yaffs_obj_hdr *oh = (struct yaffs_obj_hdr *)buffer;
4427 
4428 		memset(buffer, 0, obj->my_dev->data_bytes_per_chunk);
4429 
4430 		if (obj->hdr_chunk > 0) {
4431 			yaffs_rd_chunk_tags_nand(obj->my_dev,
4432 						 obj->hdr_chunk,
4433 						 buffer, NULL);
4434 		}
4435 		yaffs_load_name_from_oh(obj->my_dev, name, oh->name,
4436 					buffer_size);
4437 
4438 		yaffs_release_temp_buffer(obj->my_dev, buffer);
4439 	}
4440 
4441 	yaffs_fix_null_name(obj, name, buffer_size);
4442 
4443 	return yaffs_strnlen(name, YAFFS_MAX_NAME_LENGTH);
4444 }
4445 
yaffs_get_obj_length(struct yaffs_obj * obj)4446 loff_t yaffs_get_obj_length(struct yaffs_obj *obj)
4447 {
4448 	/* Dereference any hard linking */
4449 	obj = yaffs_get_equivalent_obj(obj);
4450 
4451 	if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE)
4452 		return obj->variant.file_variant.file_size;
4453 	if (obj->variant_type == YAFFS_OBJECT_TYPE_SYMLINK) {
4454 		if (!obj->variant.symlink_variant.alias)
4455 			return 0;
4456 		return yaffs_strnlen(obj->variant.symlink_variant.alias,
4457 				     YAFFS_MAX_ALIAS_LENGTH);
4458 	} else {
4459 		/* Only a directory should drop through to here */
4460 		return obj->my_dev->data_bytes_per_chunk;
4461 	}
4462 }
4463 
yaffs_get_obj_link_count(struct yaffs_obj * obj)4464 int yaffs_get_obj_link_count(struct yaffs_obj *obj)
4465 {
4466 	int count = 0;
4467 	struct list_head *i;
4468 
4469 	if (!obj->unlinked)
4470 		count++;	/* the object itself */
4471 
4472 	list_for_each(i, &obj->hard_links)
4473 	    count++;		/* add the hard links; */
4474 
4475 	return count;
4476 }
4477 
yaffs_get_obj_inode(struct yaffs_obj * obj)4478 int yaffs_get_obj_inode(struct yaffs_obj *obj)
4479 {
4480 	obj = yaffs_get_equivalent_obj(obj);
4481 
4482 	return obj->obj_id;
4483 }
4484 
yaffs_get_obj_type(struct yaffs_obj * obj)4485 unsigned yaffs_get_obj_type(struct yaffs_obj *obj)
4486 {
4487 	obj = yaffs_get_equivalent_obj(obj);
4488 
4489 	switch (obj->variant_type) {
4490 	case YAFFS_OBJECT_TYPE_FILE:
4491 		return DT_REG;
4492 		break;
4493 	case YAFFS_OBJECT_TYPE_DIRECTORY:
4494 		return DT_DIR;
4495 		break;
4496 	case YAFFS_OBJECT_TYPE_SYMLINK:
4497 		return DT_LNK;
4498 		break;
4499 	case YAFFS_OBJECT_TYPE_HARDLINK:
4500 		return DT_REG;
4501 		break;
4502 	case YAFFS_OBJECT_TYPE_SPECIAL:
4503 		if (S_ISFIFO(obj->yst_mode))
4504 			return DT_FIFO;
4505 		if (S_ISCHR(obj->yst_mode))
4506 			return DT_CHR;
4507 		if (S_ISBLK(obj->yst_mode))
4508 			return DT_BLK;
4509 		if (S_ISSOCK(obj->yst_mode))
4510 			return DT_SOCK;
4511 		return DT_REG;
4512 		break;
4513 	default:
4514 		return DT_REG;
4515 		break;
4516 	}
4517 }
4518 
yaffs_get_symlink_alias(struct yaffs_obj * obj)4519 YCHAR *yaffs_get_symlink_alias(struct yaffs_obj *obj)
4520 {
4521 	obj = yaffs_get_equivalent_obj(obj);
4522 	if (obj->variant_type == YAFFS_OBJECT_TYPE_SYMLINK)
4523 		return yaffs_clone_str(obj->variant.symlink_variant.alias);
4524 	else
4525 		return yaffs_clone_str(_Y(""));
4526 }
4527 
4528 /*--------------------------- Initialisation code -------------------------- */
4529 
yaffs_check_dev_fns(const struct yaffs_dev * dev)4530 static int yaffs_check_dev_fns(const struct yaffs_dev *dev)
4531 {
4532 	/* Common functions, gotta have */
4533 	if (!dev->param.erase_fn || !dev->param.initialise_flash_fn)
4534 		return 0;
4535 
4536 	/* Can use the "with tags" style interface for yaffs1 or yaffs2 */
4537 	if (dev->param.write_chunk_tags_fn &&
4538 	    dev->param.read_chunk_tags_fn &&
4539 	    !dev->param.write_chunk_fn &&
4540 	    !dev->param.read_chunk_fn &&
4541 	    dev->param.bad_block_fn && dev->param.query_block_fn)
4542 		return 1;
4543 
4544 	/* Can use the "spare" style interface for yaffs1 */
4545 	if (!dev->param.is_yaffs2 &&
4546 	    !dev->param.write_chunk_tags_fn &&
4547 	    !dev->param.read_chunk_tags_fn &&
4548 	    dev->param.write_chunk_fn &&
4549 	    dev->param.read_chunk_fn &&
4550 	    !dev->param.bad_block_fn && !dev->param.query_block_fn)
4551 		return 1;
4552 
4553 	return 0;		/* bad */
4554 }
4555 
yaffs_create_initial_dir(struct yaffs_dev * dev)4556 static int yaffs_create_initial_dir(struct yaffs_dev *dev)
4557 {
4558 	/* Initialise the unlinked, deleted, root and lost+found directories */
4559 	dev->lost_n_found = dev->root_dir = NULL;
4560 	dev->unlinked_dir = dev->del_dir = NULL;
4561 	dev->unlinked_dir =
4562 	    yaffs_create_fake_dir(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
4563 	dev->del_dir =
4564 	    yaffs_create_fake_dir(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
4565 	dev->root_dir =
4566 	    yaffs_create_fake_dir(dev, YAFFS_OBJECTID_ROOT,
4567 				  YAFFS_ROOT_MODE | S_IFDIR);
4568 	dev->lost_n_found =
4569 	    yaffs_create_fake_dir(dev, YAFFS_OBJECTID_LOSTNFOUND,
4570 				  YAFFS_LOSTNFOUND_MODE | S_IFDIR);
4571 
4572 	if (dev->lost_n_found && dev->root_dir && dev->unlinked_dir
4573 	    && dev->del_dir) {
4574 		yaffs_add_obj_to_dir(dev->root_dir, dev->lost_n_found);
4575 		return YAFFS_OK;
4576 	}
4577 	return YAFFS_FAIL;
4578 }
4579 
yaffs_guts_initialise(struct yaffs_dev * dev)4580 int yaffs_guts_initialise(struct yaffs_dev *dev)
4581 {
4582 	int init_failed = 0;
4583 	unsigned x;
4584 	int bits;
4585 
4586 	yaffs_trace(YAFFS_TRACE_TRACING, "yaffs: yaffs_guts_initialise()");
4587 
4588 	/* Check stuff that must be set */
4589 
4590 	if (!dev) {
4591 		yaffs_trace(YAFFS_TRACE_ALWAYS,
4592 			"yaffs: Need a device"
4593 			);
4594 		return YAFFS_FAIL;
4595 	}
4596 
4597 	if (dev->is_mounted) {
4598 		yaffs_trace(YAFFS_TRACE_ALWAYS, "device already mounted");
4599 		return YAFFS_FAIL;
4600 	}
4601 
4602 	dev->internal_start_block = dev->param.start_block;
4603 	dev->internal_end_block = dev->param.end_block;
4604 	dev->block_offset = 0;
4605 	dev->chunk_offset = 0;
4606 	dev->n_free_chunks = 0;
4607 
4608 	dev->gc_block = 0;
4609 
4610 	if (dev->param.start_block == 0) {
4611 		dev->internal_start_block = dev->param.start_block + 1;
4612 		dev->internal_end_block = dev->param.end_block + 1;
4613 		dev->block_offset = 1;
4614 		dev->chunk_offset = dev->param.chunks_per_block;
4615 	}
4616 
4617 	/* Check geometry parameters. */
4618 
4619 	if ((!dev->param.inband_tags && dev->param.is_yaffs2 &&
4620 		dev->param.total_bytes_per_chunk < 1024) ||
4621 		(!dev->param.is_yaffs2 &&
4622 			dev->param.total_bytes_per_chunk < 512) ||
4623 		(dev->param.inband_tags && !dev->param.is_yaffs2) ||
4624 		 dev->param.chunks_per_block < 2 ||
4625 		 dev->param.n_reserved_blocks < 2 ||
4626 		dev->internal_start_block <= 0 ||
4627 		dev->internal_end_block <= 0 ||
4628 		dev->internal_end_block <=
4629 		(dev->internal_start_block + dev->param.n_reserved_blocks + 2)
4630 		) {
4631 		/* otherwise it is too small */
4632 		yaffs_trace(YAFFS_TRACE_ALWAYS,
4633 			"NAND geometry problems: chunk size %d, type is yaffs%s, inband_tags %d ",
4634 			dev->param.total_bytes_per_chunk,
4635 			dev->param.is_yaffs2 ? "2" : "",
4636 			dev->param.inband_tags);
4637 		return YAFFS_FAIL;
4638 	}
4639 
4640 	if (yaffs_init_nand(dev) != YAFFS_OK) {
4641 		yaffs_trace(YAFFS_TRACE_ALWAYS, "InitialiseNAND failed");
4642 		return YAFFS_FAIL;
4643 	}
4644 
4645 	/* Sort out space for inband tags, if required */
4646 	if (dev->param.inband_tags)
4647 		dev->data_bytes_per_chunk =
4648 		    dev->param.total_bytes_per_chunk -
4649 		    sizeof(struct yaffs_packed_tags2_tags_only);
4650 	else
4651 		dev->data_bytes_per_chunk = dev->param.total_bytes_per_chunk;
4652 
4653 	/* Got the right mix of functions? */
4654 	if (!yaffs_check_dev_fns(dev)) {
4655 		/* Function missing */
4656 		yaffs_trace(YAFFS_TRACE_ALWAYS,
4657 			"device function(s) missing or wrong");
4658 
4659 		return YAFFS_FAIL;
4660 	}
4661 
4662 	/* Finished with most checks. Further checks happen later on too. */
4663 
4664 	dev->is_mounted = 1;
4665 
4666 	/* OK now calculate a few things for the device */
4667 
4668 	/*
4669 	 *  Calculate all the chunk size manipulation numbers:
4670 	 */
4671 	x = dev->data_bytes_per_chunk;
4672 	/* We always use dev->chunk_shift and dev->chunk_div */
4673 	dev->chunk_shift = calc_shifts(x);
4674 	x >>= dev->chunk_shift;
4675 	dev->chunk_div = x;
4676 	/* We only use chunk mask if chunk_div is 1 */
4677 	dev->chunk_mask = (1 << dev->chunk_shift) - 1;
4678 
4679 	/*
4680 	 * Calculate chunk_grp_bits.
4681 	 * We need to find the next power of 2 > than internal_end_block
4682 	 */
4683 
4684 	x = dev->param.chunks_per_block * (dev->internal_end_block + 1);
4685 
4686 	bits = calc_shifts_ceiling(x);
4687 
4688 	/* Set up tnode width if wide tnodes are enabled. */
4689 	if (!dev->param.wide_tnodes_disabled) {
4690 		/* bits must be even so that we end up with 32-bit words */
4691 		if (bits & 1)
4692 			bits++;
4693 		if (bits < 16)
4694 			dev->tnode_width = 16;
4695 		else
4696 			dev->tnode_width = bits;
4697 	} else {
4698 		dev->tnode_width = 16;
4699 	}
4700 
4701 	dev->tnode_mask = (1 << dev->tnode_width) - 1;
4702 
4703 	/* Level0 Tnodes are 16 bits or wider (if wide tnodes are enabled),
4704 	 * so if the bitwidth of the
4705 	 * chunk range we're using is greater than 16 we need
4706 	 * to figure out chunk shift and chunk_grp_size
4707 	 */
4708 
4709 	if (bits <= dev->tnode_width)
4710 		dev->chunk_grp_bits = 0;
4711 	else
4712 		dev->chunk_grp_bits = bits - dev->tnode_width;
4713 
4714 	dev->tnode_size = (dev->tnode_width * YAFFS_NTNODES_LEVEL0) / 8;
4715 	if (dev->tnode_size < sizeof(struct yaffs_tnode))
4716 		dev->tnode_size = sizeof(struct yaffs_tnode);
4717 
4718 	dev->chunk_grp_size = 1 << dev->chunk_grp_bits;
4719 
4720 	if (dev->param.chunks_per_block < dev->chunk_grp_size) {
4721 		/* We have a problem because the soft delete won't work if
4722 		 * the chunk group size > chunks per block.
4723 		 * This can be remedied by using larger "virtual blocks".
4724 		 */
4725 		yaffs_trace(YAFFS_TRACE_ALWAYS, "chunk group too large");
4726 
4727 		return YAFFS_FAIL;
4728 	}
4729 
4730 	/* Finished verifying the device, continue with initialisation */
4731 
4732 	/* More device initialisation */
4733 	dev->all_gcs = 0;
4734 	dev->passive_gc_count = 0;
4735 	dev->oldest_dirty_gc_count = 0;
4736 	dev->bg_gcs = 0;
4737 	dev->gc_block_finder = 0;
4738 	dev->buffered_block = -1;
4739 	dev->doing_buffered_block_rewrite = 0;
4740 	dev->n_deleted_files = 0;
4741 	dev->n_bg_deletions = 0;
4742 	dev->n_unlinked_files = 0;
4743 	dev->n_ecc_fixed = 0;
4744 	dev->n_ecc_unfixed = 0;
4745 	dev->n_tags_ecc_fixed = 0;
4746 	dev->n_tags_ecc_unfixed = 0;
4747 	dev->n_erase_failures = 0;
4748 	dev->n_erased_blocks = 0;
4749 	dev->gc_disable = 0;
4750 	dev->has_pending_prioritised_gc = 1;
4751 		/* Assume the worst for now, will get fixed on first GC */
4752 	INIT_LIST_HEAD(&dev->dirty_dirs);
4753 	dev->oldest_dirty_seq = 0;
4754 	dev->oldest_dirty_block = 0;
4755 
4756 	/* Initialise temporary buffers and caches. */
4757 	if (!yaffs_init_tmp_buffers(dev))
4758 		init_failed = 1;
4759 
4760 	dev->cache = NULL;
4761 	dev->gc_cleanup_list = NULL;
4762 
4763 	if (!init_failed && dev->param.n_caches > 0) {
4764 		int i;
4765 		void *buf;
4766 		int cache_bytes =
4767 		    dev->param.n_caches * sizeof(struct yaffs_cache);
4768 
4769 		if (dev->param.n_caches > YAFFS_MAX_SHORT_OP_CACHES)
4770 			dev->param.n_caches = YAFFS_MAX_SHORT_OP_CACHES;
4771 
4772 		dev->cache = kmalloc(cache_bytes, GFP_NOFS);
4773 
4774 		buf = (u8 *) dev->cache;
4775 
4776 		if (dev->cache)
4777 			memset(dev->cache, 0, cache_bytes);
4778 
4779 		for (i = 0; i < dev->param.n_caches && buf; i++) {
4780 			dev->cache[i].object = NULL;
4781 			dev->cache[i].last_use = 0;
4782 			dev->cache[i].dirty = 0;
4783 			dev->cache[i].data = buf =
4784 			    kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
4785 		}
4786 		if (!buf)
4787 			init_failed = 1;
4788 
4789 		dev->cache_last_use = 0;
4790 	}
4791 
4792 	dev->cache_hits = 0;
4793 
4794 	if (!init_failed) {
4795 		dev->gc_cleanup_list =
4796 		    kmalloc(dev->param.chunks_per_block * sizeof(u32),
4797 					GFP_NOFS);
4798 		if (!dev->gc_cleanup_list)
4799 			init_failed = 1;
4800 	}
4801 
4802 	if (dev->param.is_yaffs2)
4803 		dev->param.use_header_file_size = 1;
4804 
4805 	if (!init_failed && !yaffs_init_blocks(dev))
4806 		init_failed = 1;
4807 
4808 	yaffs_init_tnodes_and_objs(dev);
4809 
4810 	if (!init_failed && !yaffs_create_initial_dir(dev))
4811 		init_failed = 1;
4812 
4813 	if (!init_failed && dev->param.is_yaffs2 &&
4814 		!dev->param.disable_summary &&
4815 		!yaffs_summary_init(dev))
4816 		init_failed = 1;
4817 
4818 	if (!init_failed) {
4819 		/* Now scan the flash. */
4820 		if (dev->param.is_yaffs2) {
4821 			if (yaffs2_checkpt_restore(dev)) {
4822 				yaffs_check_obj_details_loaded(dev->root_dir);
4823 				yaffs_trace(YAFFS_TRACE_CHECKPOINT |
4824 					YAFFS_TRACE_MOUNT,
4825 					"yaffs: restored from checkpoint"
4826 					);
4827 			} else {
4828 
4829 				/* Clean up the mess caused by an aborted
4830 				 * checkpoint load then scan backwards.
4831 				 */
4832 				yaffs_deinit_blocks(dev);
4833 
4834 				yaffs_deinit_tnodes_and_objs(dev);
4835 
4836 				dev->n_erased_blocks = 0;
4837 				dev->n_free_chunks = 0;
4838 				dev->alloc_block = -1;
4839 				dev->alloc_page = -1;
4840 				dev->n_deleted_files = 0;
4841 				dev->n_unlinked_files = 0;
4842 				dev->n_bg_deletions = 0;
4843 
4844 				if (!init_failed && !yaffs_init_blocks(dev))
4845 					init_failed = 1;
4846 
4847 				yaffs_init_tnodes_and_objs(dev);
4848 
4849 				if (!init_failed
4850 				    && !yaffs_create_initial_dir(dev))
4851 					init_failed = 1;
4852 
4853 				if (!init_failed && !yaffs2_scan_backwards(dev))
4854 					init_failed = 1;
4855 			}
4856 		} else if (!yaffs1_scan(dev)) {
4857 			init_failed = 1;
4858 		}
4859 
4860 		yaffs_strip_deleted_objs(dev);
4861 		yaffs_fix_hanging_objs(dev);
4862 		if (dev->param.empty_lost_n_found)
4863 			yaffs_empty_l_n_f(dev);
4864 	}
4865 
4866 	if (init_failed) {
4867 		/* Clean up the mess */
4868 		yaffs_trace(YAFFS_TRACE_TRACING,
4869 		  "yaffs: yaffs_guts_initialise() aborted.");
4870 
4871 		yaffs_deinitialise(dev);
4872 		return YAFFS_FAIL;
4873 	}
4874 
4875 	/* Zero out stats */
4876 	dev->n_page_reads = 0;
4877 	dev->n_page_writes = 0;
4878 	dev->n_erasures = 0;
4879 	dev->n_gc_copies = 0;
4880 	dev->n_retried_writes = 0;
4881 
4882 	dev->n_retired_blocks = 0;
4883 
4884 	yaffs_verify_free_chunks(dev);
4885 	yaffs_verify_blocks(dev);
4886 
4887 	/* Clean up any aborted checkpoint data */
4888 	if (!dev->is_checkpointed && dev->blocks_in_checkpt > 0)
4889 		yaffs2_checkpt_invalidate(dev);
4890 
4891 	yaffs_trace(YAFFS_TRACE_TRACING,
4892 	  "yaffs: yaffs_guts_initialise() done.");
4893 	return YAFFS_OK;
4894 }
4895 
yaffs_deinitialise(struct yaffs_dev * dev)4896 void yaffs_deinitialise(struct yaffs_dev *dev)
4897 {
4898 	if (dev->is_mounted) {
4899 		int i;
4900 
4901 		yaffs_deinit_blocks(dev);
4902 		yaffs_deinit_tnodes_and_objs(dev);
4903 		yaffs_summary_deinit(dev);
4904 
4905 		if (dev->param.n_caches > 0 && dev->cache) {
4906 
4907 			for (i = 0; i < dev->param.n_caches; i++) {
4908 				kfree(dev->cache[i].data);
4909 				dev->cache[i].data = NULL;
4910 			}
4911 
4912 			kfree(dev->cache);
4913 			dev->cache = NULL;
4914 		}
4915 
4916 		kfree(dev->gc_cleanup_list);
4917 
4918 		for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
4919 			kfree(dev->temp_buffer[i].buffer);
4920 
4921 		dev->is_mounted = 0;
4922 
4923 		if (dev->param.deinitialise_flash_fn)
4924 			dev->param.deinitialise_flash_fn(dev);
4925 	}
4926 }
4927 
yaffs_count_free_chunks(struct yaffs_dev * dev)4928 int yaffs_count_free_chunks(struct yaffs_dev *dev)
4929 {
4930 	int n_free = 0;
4931 	int b;
4932 	struct yaffs_block_info *blk;
4933 
4934 	blk = dev->block_info;
4935 	for (b = dev->internal_start_block; b <= dev->internal_end_block; b++) {
4936 		switch (blk->block_state) {
4937 		case YAFFS_BLOCK_STATE_EMPTY:
4938 		case YAFFS_BLOCK_STATE_ALLOCATING:
4939 		case YAFFS_BLOCK_STATE_COLLECTING:
4940 		case YAFFS_BLOCK_STATE_FULL:
4941 			n_free +=
4942 			    (dev->param.chunks_per_block - blk->pages_in_use +
4943 			     blk->soft_del_pages);
4944 			break;
4945 		default:
4946 			break;
4947 		}
4948 		blk++;
4949 	}
4950 	return n_free;
4951 }
4952 
yaffs_get_n_free_chunks(struct yaffs_dev * dev)4953 int yaffs_get_n_free_chunks(struct yaffs_dev *dev)
4954 {
4955 	/* This is what we report to the outside world */
4956 	int n_free;
4957 	int n_dirty_caches;
4958 	int blocks_for_checkpt;
4959 	int i;
4960 
4961 	n_free = dev->n_free_chunks;
4962 	n_free += dev->n_deleted_files;
4963 
4964 	/* Now count and subtract the number of dirty chunks in the cache. */
4965 
4966 	for (n_dirty_caches = 0, i = 0; i < dev->param.n_caches; i++) {
4967 		if (dev->cache[i].dirty)
4968 			n_dirty_caches++;
4969 	}
4970 
4971 	n_free -= n_dirty_caches;
4972 
4973 	n_free -=
4974 	    ((dev->param.n_reserved_blocks + 1) * dev->param.chunks_per_block);
4975 
4976 	/* Now figure checkpoint space and report that... */
4977 	blocks_for_checkpt = yaffs_calc_checkpt_blocks_required(dev);
4978 
4979 	n_free -= (blocks_for_checkpt * dev->param.chunks_per_block);
4980 
4981 	if (n_free < 0)
4982 		n_free = 0;
4983 
4984 	return n_free;
4985 }
4986 
4987 /*\
4988  * Marshalling functions to get loff_t file sizes into aand out of
4989  * object headers.
4990  */
yaffs_oh_size_load(struct yaffs_obj_hdr * oh,loff_t fsize)4991 void yaffs_oh_size_load(struct yaffs_obj_hdr *oh, loff_t fsize)
4992 {
4993 	oh->file_size_low = (fsize & 0xFFFFFFFF);
4994 	oh->file_size_high = ((fsize >> 32) & 0xFFFFFFFF);
4995 }
4996 
yaffs_oh_to_size(struct yaffs_obj_hdr * oh)4997 loff_t yaffs_oh_to_size(struct yaffs_obj_hdr *oh)
4998 {
4999 	loff_t retval;
5000 
5001 	if (~(oh->file_size_high))
5002 		retval = (((loff_t) oh->file_size_high) << 32) |
5003 			(((loff_t) oh->file_size_low) & 0xFFFFFFFF);
5004 	else
5005 		retval = (loff_t) oh->file_size_low;
5006 
5007 	return retval;
5008 }
5009