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fatfs.c @ 507

Last change on this file since 507 was 492, checked in by viala@…, 6 years ago

Refactoring assert calling to conform with new assert macro.

Made with this command for the general case.
find ./kernel/ hal/ -name "*.c" | xargs sed -i -e '/assert(/ s/,[ ]*FUNCTION[ ]*,/,/'

And some done by hand.

File size: 27.5 KB

Line
1	/*
2	* fatfs.c - FATFS file system API implementation.
3	*
4	* Author Alain Greiner (2016,2017)
5	*
6	* Copyright (c) UPMC Sorbonne Universites
7	*
8	* This file is part of ALMOS-MKH.
9	*
10	* ALMOS-MKH is free software; you can redistribute it and/or modify it
11	* under the terms of the GNU General Public License as published by
12	* the Free Software Foundation; version 2.0 of the License.
13	*
14	* ALMOS-MKH is distributed in the hope that it will be useful, but
15	* WITHOUT ANY WARRANTY; without even the implied warranty of
16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17	* General Public License for more details.
18	*
19	* You should have received a copy of the GNU General Public License
20	* along with ALMOS-MKH; if not, write to the Free Software Foundation,
21	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22	*/
23
24
25	#include <hal_kernel_types.h>
26	#include <hal_special.h>
27	#include <printk.h>
28	#include <thread.h>
29	#include <kmem.h>
30	#include <ppm.h>
31	#include <vfs.h>
32	#include <string.h>
33	#include <rpc.h>
34	#include <mapper.h>
35	#include <cluster.h>
36	#include <dev_ioc.h>
37	#include <fatfs.h>
38
39
40	//////////////////////////////////////////////////////////////////////////////////////////
41	// Extern variables
42	//////////////////////////////////////////////////////////////////////////////////////////
43
44	extern vfs_ctx_t fs_context[FS_TYPES_NR]; // allocated in vfs.c file
45
46	extern remote_barrier_t global_barrier; // allocated in kernel_init.c
47
48	//////////////////////////////////////////////////////////////////////////////////////////
49	// FATFS specific and static functions
50	//////////////////////////////////////////////////////////////////////////////////////////
51
52	//////////////////////////////////////////////////////////////////////////////////////////
53	// These functions return the "offset" and "length" values of an
54	// [offset,length] constant defined in the fatfs.h file.
55	//////////////////////////////////////////////////////////////////////////////////////////
56
57	static inline int get_length( int offset , int length ) { if( offset + 1 ) return length; }
58
59	static inline int get_offset( int offset , int length ) { if( length + 1 ) return offset; }
60
61
62	//////////////////////////////////////////////////////////////////////////////////////////
63	// This static function returns the LBA of the first sector of a FAT cluster.
64	// This function can be called by any thread running in any cluster.
65	//////////////////////////////////////////////////////////////////////////////////////////
66	// @ ctx : pointer on FATFS context.
67	// @ cluster : cluster index in FATFS.
68	// @ return the lba value.
69	//////////////////////////////////////////////////////////////////////////////////////////
70	static inline uint32_t fatfs_lba_from_cluster( fatfs_ctx_t * ctx,
71	uint32_t cluster )
72	{
73	return (ctx->cluster_begin_lba + ((cluster - 2) << 3));
74	}
75
76	//////////////////////////////////////////////////////////////////////////////////////////
77	// This function return an integer record value (one, two, or four bytes)
78	// from a memory buffer, taking into account endianness.
79	//////////////////////////////////////////////////////////////////////////////////////////
80	// @ offset : first byte of record in buffer.
81	// @ size : record length in bytes (1/2/4).
82	// @ buffer : pointer on buffer base.
83	// @ little endian : the most significant byte has the highest address when true.
84	// @ return the integer value in a 32 bits word.
85	//////////////////////////////////////////////////////////////////////////////////////////
86	static uint32_t fatfs_get_record( uint32_t offset,
87	uint32_t size,
88	uint8_t * buffer,
89	uint32_t little_endian )
90	{
91	uint32_t n;
92	uint32_t res = 0;
93
94	if ( little_endian)
95	{
96	for( n = size ; n > 0 ; n-- ) res = (res<<8) \| buffer[offset+n-1];
97	}
98	else
99	{
100	for( n = 0 ; n < size ; n++ ) res = (res<<8) \| buffer[offset+n];
101	}
102	return res;
103
104	} // end fatfs_get_record()
105
106	//////////////////////////////////////////////////////////////////////////////////////////
107	// This static function retun in the <name> buffer a short name stored in
108	// a SFN FATFS directory entry.
109	/////////////////////////i////////////////////////////////////////////////////////////////
110	// @ buffer : pointer on buffer containing the directory entry.
111	// @ name : [out] buffer allocated by the caller.
112	//////////////////////////////////////////////////////////////////////////////////////////
113	static void fatfs_get_name_from_short( uint8_t * buffer,
114	char * name )
115	{
116	uint32_t i;
117	uint32_t j = 0;
118
119	// get name
120	for ( i = 0; i < 8 && buffer[i] != ' '; i++ )
121	{
122	name[j] = to_lower( buffer[i] );
123	j++;
124	}
125
126	// get extension
127	for ( i = 8; i < 8 + 3 && buffer[i] != ' '; i++ )
128	{
129	// we entered the loop so there is an extension. add the dot
130	if ( i == 8 )
131	{
132	name[j] = '.';
133	j++;
134	}
135
136	name[j] = to_lower( buffer[i] );
137	j++;
138	}
139
140	name[j] = '\0';
141	}
142
143	//////////////////////////////////////////////////////////////////////////////////////////
144	// This static function retun in the <name> buffer a partial name stored in
145	// a LFN FATFS directory entry.
146	/////////////////////////i////////////////////////////////////////////////////////////////
147	// @ buffer : pointer on buffer containing the directory entry.
148	// @ name : [out] buffer allocated by the caller.
149	//////////////////////////////////////////////////////////////////////////////////////////
150	static void fatfs_get_name_from_long( uint8_t * buffer,
151	char * name )
152	{
153	uint32_t name_offset = 0;
154	uint32_t buffer_offset = get_length(LDIR_ORD);
155	uint32_t l_name_1 = get_length(LDIR_NAME_1);
156	uint32_t l_name_2 = get_length(LDIR_NAME_2);
157	uint32_t l_name_3 = get_length(LDIR_NAME_3);
158	uint32_t l_attr = get_length(LDIR_ATTR);
159	uint32_t l_type = get_length(LDIR_TYPE);
160	uint32_t l_chksum = get_length(LDIR_CHKSUM);
161	uint32_t l_rsvd = get_length(LDIR_RSVD);
162
163	uint32_t j = 0;
164	uint32_t eof = 0;
165
166	while ( (buffer_offset != DIR_ENTRY_SIZE) && (!eof) )
167	{
168	while (j != l_name_1 && !eof )
169	{
170	if ( (buffer[buffer_offset] == 0x00) \|\|
171	(buffer[buffer_offset] == 0xFF) )
172	{
173	eof = 1;
174	continue;
175	}
176	name[name_offset] = buffer[buffer_offset];
177	buffer_offset += 2;
178	j += 2;
179	name_offset++;
180	}
181
182	buffer_offset += (l_attr + l_type + l_chksum);
183	j = 0;
184
185	while (j != l_name_2 && !eof )
186	{
187	if ( (buffer[buffer_offset] == 0x00) \|\|
188	(buffer[buffer_offset] == 0xFF) )
189	{
190	eof = 1;
191	continue;
192	}
193	name[name_offset] = buffer[buffer_offset];
194	buffer_offset += 2;
195	j += 2;
196	name_offset++;
197	}
198
199	buffer_offset += l_rsvd;
200	j = 0;
201
202	while (j != l_name_3 && !eof )
203	{
204	if ( (buffer[buffer_offset] == 0x00) \|\|
205	(buffer[buffer_offset] == 0xFF) )
206	{
207	eof = 1;
208	continue;
209	}
210	name[name_offset] = buffer[buffer_offset];
211	buffer_offset += 2;
212	j += 2;
213	name_offset++;
214	}
215	}
216	name[name_offset] = 0;
217
218	} // end get_name_from_long()
219
220
221	//////////////////////////////////////////////////////////////////////////////////////////
222	// FATFS specific but extern functions
223	//////////////////////////////////////////////////////////////////////////////////////////
224
225	//////////////////////////////////////////////////////////////////////////////////////////
226	void fatfs_ctx_display( void )
227	{
228	vfs_ctx_t * vfs_ctx = &fs_context[FS_TYPE_FATFS];
229	fatfs_ctx_t * fatfs_ctx = (fatfs_ctx_t *)vfs_ctx->extend;
230
231	printk("\n* FAT context *\n"
232	"- fat_sectors = %d\n"
233	"- sector size = %d\n"
234	"- cluster size = %d\n"
235	"- fat_first_lba = %d\n"
236	"- data_first_lba = %d\n"
237	"- root_dir_cluster = %d\n"
238	"- mapper_xp = %l\n",
239	fatfs_ctx->fat_sectors_count,
240	fatfs_ctx->bytes_per_sector,
241	fatfs_ctx->sectors_per_cluster * fatfs_ctx->bytes_per_sector,
242	fatfs_ctx->fat_begin_lba,
243	fatfs_ctx->cluster_begin_lba,
244	fatfs_ctx->root_dir_cluster,
245	fatfs_ctx->fat_mapper_xp );
246	}
247
248	/////////////////////////////////////////////
249	error_t fatfs_get_cluster( mapper_t * mapper,
250	uint32_t first_cluster_id,
251	uint32_t searched_page_index,
252	uint32_t * searched_cluster_id )
253	{
254	page_t * current_page_desc; // pointer on current page descriptor
255	uint32_t * current_page_buffer; // pointer on current page (array of uint32_t)
256	uint32_t current_page_index; // index of current page in FAT
257	uint32_t current_page_offset; // offset of slot in current page
258	uint32_t page_count_in_file; // index of page in file (index in linked list)
259	uint32_t next_cluster_id; // content of current FAT slot
260
261	assert( (searched_page_index > 0) ,
262	"no FAT access required for first page\n");
263
264	#if DEBUG_FATFS_GET_CLUSTER
265	uint32_t cycle = (uint32_t)hal_get_cycles();
266	if( DEBUG_FATFS_GET_CLUSTER < cycle )
267	printk("\n[DBG] %s : thread %x enter / first_cluster_id %d / searched_index / cycle %d\n",
268	__FUNCTION__, CURRENT_THREAD, first_cluster_id, searched_page_index, cycle );
269	#endif
270
271	// get number of FAT slots per page
272	uint32_t slots_per_page = CONFIG_PPM_PAGE_SIZE >> 2;
273
274	// initialize loop variable
275	current_page_index = first_cluster_id / slots_per_page;
276	current_page_offset = first_cluster_id % slots_per_page;
277	page_count_in_file = 0;
278	next_cluster_id = 0xFFFFFFFF;
279
280	// scan FAT (i.e. traverse FAT linked list)
281	while( page_count_in_file < searched_page_index )
282	{
283	// get pointer on current page descriptor
284	current_page_desc = mapper_get_page( mapper , current_page_index );
285
286	if( current_page_desc == NULL ) return EIO;
287
288	// get pointer on buffer for current page
289	xptr_t base_xp = ppm_page2base( XPTR( local_cxy , current_page_desc ) );
290	current_page_buffer = (uint32_t *)GET_PTR( base_xp );
291
292	// get FAT slot content
293	next_cluster_id = current_page_buffer[current_page_offset];
294
295	#if (DEBUG_FATFS_GET_CLUSTER & 1)
296	if( DEBUG_FATFS_GET_CLUSTER < cycle )
297	printk("\n[DBG] %s : traverse FAT / current_page_index = %d\n"
298	"current_page_offset = %d / next_cluster_id = %d\n",
299	__FUNCTION__, current_page_index, current_page_offset , next_cluster_id );
300	#endif
301
302	// update loop variables
303	current_page_index = next_cluster_id / slots_per_page;
304	current_page_offset = next_cluster_id % slots_per_page;
305	page_count_in_file++;
306	}
307
308	if( next_cluster_id == 0xFFFFFFFF ) return EIO;
309
310	#if DEBUG_FATFS_GET_CLUSTER
311	cycle = (uint32_t)hal_get_cycles();
312	if( DEBUG_FATFS_GET_CLUSTER < cycle )
313	printk("\n[DBG] %s : thread %x exit / searched_cluster_id = %d / cycle %d\n",
314	__FUNCTION__, CURRENT_THREAD, next_cluster_id / cycle );
315	#endif
316
317	*searched_cluster_id = next_cluster_id;
318	return 0;
319
320	} // end fatfs_get_cluster()
321
322
323
324	///////////////////////////////////////////////////////////////////////////////////////
325	// Generic API : the following functions are called by the kernel (VFS)
326	// and must be defined by all supported file systems.
327	///////////////////////////////////////////////////////////////////////////////////////
328
329	///////////////////////////////
330	fatfs_ctx_t * fatfs_ctx_alloc( void )
331	{
332	kmem_req_t req;
333	req.type = KMEM_FATFS_CTX;
334	req.size = sizeof(fatfs_ctx_t);
335	req.flags = AF_KERNEL \| AF_ZERO;
336
337	return (fatfs_ctx_t *)kmem_alloc( &req );
338	}
339
340	//////////////////////////////////////////////
341	void fatfs_ctx_init( fatfs_ctx_t * fatfs_ctx )
342	{
343	error_t error;
344	kmem_req_t req;
345	uint8_t * buffer;
346
347	#if DEBUG_FATFS_INIT
348	uint32_t cycle = (uint32_t)hal_get_cycles();
349	if( DEBUG_FATFS_INIT < cycle )
350	printk("\n[DBG] %s : thread %x enter for fatfs_ctx = %x / cycle %d\n",
351	__FUNCTION__ , CURRENT_THREAD , fatfs_ctx , cycle );
352	#endif
353
354	assert( (fatfs_ctx != NULL) ,
355	"cannot allocate memory for FATFS context\n" );
356
357	// allocate a 512 bytes buffer to store the boot record
358	req.type = KMEM_512_BYTES;
359	req.flags = AF_KERNEL \| AF_ZERO;
360	buffer = (uint8_t *)kmem_alloc( &req );
361
362	assert( (buffer != NULL) ,
363	"cannot allocate memory for 512 bytes buffer\n" );
364
365	// load the boot record from device
366	// using a synchronous access to IOC device
367	error = dev_ioc_sync_read( buffer , 0 , 1 );
368
369	assert( (error == 0) ,
370	"cannot access boot record\n" );
371
372	#if (DEBUG_FATFS_INIT & 0x1)
373	if( DEBUG_FATFS_INIT < cycle )
374	{
375	uint32_t line;
376	uint32_t byte = 0;
377	printk("\n***** %s : FAT boot record\n", __FUNCTION__ );
378	for ( line = 0 ; line < 32 ; line++ )
379	{
380	printk(" %X \| %x %x %x %x %x %x %x %x %x %x %x %x %x %x %x %x \|\n",
381	byte,
382	buffer[byte+ 0],buffer[byte+ 1],buffer[byte+ 2],buffer[byte+ 3],
383	buffer[byte+ 4],buffer[byte+ 5],buffer[byte+ 6],buffer[byte+ 7],
384	buffer[byte+ 8],buffer[byte+ 9],buffer[byte+10],buffer[byte+11],
385	buffer[byte+12],buffer[byte+13],buffer[byte+14],buffer[byte+15] );
386
387	byte += 16;
388	}
389	}
390	#endif
391
392	// check sector size from boot record
393	uint32_t sector_size = fatfs_get_record( BPB_BYTSPERSEC , buffer , 1 );
394
395	assert( (sector_size == 512) ,
396	"sector size must be 512 bytes\n" );
397
398	// check cluster size from boot record
399	uint32_t nb_sectors = fatfs_get_record( BPB_SECPERCLUS , buffer , 1 );
400
401	assert( (nb_sectors == 8) ,
402	"cluster size must be 8 sectors\n" );
403
404	// check number of FAT copies from boot record
405	uint32_t nb_fats = fatfs_get_record( BPB_NUMFATS , buffer , 1 );
406
407	assert( (nb_fats == 1) ,
408	"number of FAT copies must be 1\n" );
409
410	// get & check number of sectors in FAT from boot record
411	uint32_t fat_sectors = fatfs_get_record( BPB_FAT32_FATSZ32 , buffer , 1 );
412
413	assert( ((fat_sectors & 0xF) == 0) ,
414	"FAT not multiple of 16 sectors\n");
415
416	// get and check root cluster from boot record
417	uint32_t root_cluster = fatfs_get_record( BPB_FAT32_ROOTCLUS , buffer , 1 );
418
419	assert( (root_cluster == 2) ,
420	"root cluster index must be 2\n");
421
422	// get FAT lba from boot record
423	uint32_t fat_lba = fatfs_get_record( BPB_RSVDSECCNT , buffer , 1 );
424
425	// release the 512 bytes buffer
426	req.type = KMEM_512_BYTES;
427	req.ptr = buffer;
428	kmem_free( &req );
429
430	// allocate a mapper for the FAT itself
431	mapper_t * fat_mapper = mapper_create( FS_TYPE_FATFS );
432
433	assert( (fat_mapper != NULL) ,
434	"no memory for FAT mapper" );
435
436	// WARNING : the inode field MUST be NULL for the FAT mapper
437	fat_mapper->inode = NULL;
438
439	// initialize the FATFS context
440	fatfs_ctx->fat_begin_lba = fat_lba;
441	fatfs_ctx->fat_sectors_count = fat_sectors;
442	fatfs_ctx->bytes_per_sector = sector_size;
443	fatfs_ctx->sectors_per_cluster = nb_sectors;
444	fatfs_ctx->cluster_begin_lba = fat_lba + fat_sectors;
445	fatfs_ctx->root_dir_cluster = 2;
446	fatfs_ctx->last_allocated_sector = 0; // TODO ???
447	fatfs_ctx->last_allocated_index = 0; // TODO ???
448	fatfs_ctx->fat_mapper_xp = XPTR( local_cxy , fat_mapper );
449
450	#if DEBUG_FATFS_INIT
451	cycle = (uint32_t)hal_get_cycles();
452	if( DEBUG_FATFS_INIT < cycle )
453	printk("\n[DBG] %s : thread %x exit for fatfs_ctx = %x / cycle %d\n",
454	__FUNCTION__ , CURRENT_THREAD , fatfs_ctx , cycle );
455	#endif
456
457	} // end fatfs_ctx_init()
458
459	/////////////////////////////////////////////////
460	void fatfs_ctx_destroy( fatfs_ctx_t * fatfs_ctx )
461	{
462	kmem_req_t req;
463	req.type = KMEM_FATFS_CTX;
464	req.ptr = fatfs_ctx;
465	kmem_free( &req );
466	}
467
468	//////////////////////////////////////////////
469	error_t fatfs_mapper_move_page( page_t * page,
470	bool_t to_mapper )
471	{
472	error_t error;
473	vfs_inode_t * inode;
474	mapper_t * mapper;
475	uint32_t index; // page index in mapper
476	uint8_t * buffer; // page base address in mapper
477	uint32_t count; // number of sectors in a page
478	uint32_t lba; // block address on device
479	fatfs_ctx_t * fatfs_ctx; // pointer on local FATFS context
480
481	// get pointer on mapper and page index from page descriptor
482	mapper = page->mapper;
483	index = page->index;
484
485	// get inode pointer from mapper
486	inode = mapper->inode;
487
488	#if DEBUG_FATFS_MOVE
489	uint32_t cycle = (uint32_t)hal_get_cycles();
490	if( DEBUG_FATFS_MOVE < cycle )
491	printk("\n[DBG] %s : thread %x enter / page %d / inode %x / mapper %x / cycle %d\n",
492	__FUNCTION__ , CURRENT_THREAD , index , inode , mapper , cycle );
493	#endif
494
495	// get page base address
496	xptr_t base_xp = ppm_page2base( XPTR( local_cxy , page ) );
497	buffer = (uint8_t *)GET_PTR( base_xp );
498
499	// get number of sectors for one page (from FATFS context)
500	fatfs_ctx = (fatfs_ctx_t *)fs_context[FS_TYPE_FATFS].extend;
501	count = fatfs_ctx->sectors_per_cluster;
502
503	// test FAT/normal inode
504	if( inode == NULL ) // it is the FAT mapper
505	{
506	// get lba from page index
507	lba = fatfs_ctx->fat_begin_lba + (count * index);
508
509	#if (DEBUG_FATFS_MOVE & 0x1)
510	if( DEBUG_FATFS_MOVE < cycle )
511	printk("\n[DBG] %s : access FAT on device / lba = %d\n", __FUNCTION__ , lba );
512	#endif
513
514	// access device
515	if( to_mapper ) error = dev_ioc_sync_read ( buffer , lba , count );
516	else error = dev_ioc_write( buffer , lba , count );
517
518	if( error ) return EIO;
519	}
520	else // it is a normal inode mapper
521	{
522	uint32_t searched_cluster_id;
523
524	// get first_cluster_id from inode extension
525	uint32_t first_cluster_id = (uint32_t)(intptr_t)inode->extend;
526
527	// compute cluster_id
528	if( index == 0 ) // no need to access FAT mapper
529	{
530	searched_cluster_id = first_cluster_id;
531	}
532	else // FAT mapper access required
533	{
534	// get cluster and local pointer on FAT mapper
535	xptr_t fat_mapper_xp = fatfs_ctx->fat_mapper_xp;
536	cxy_t fat_mapper_cxy = GET_CXY( fat_mapper_xp );
537	mapper_t * fat_mapper_ptr = (mapper_t *)GET_PTR( fat_mapper_xp );
538
539	// access FAT mapper
540	if( fat_mapper_cxy == local_cxy ) // FAT mapper is local
541	{
542
543	#if (DEBUG_FATFS_MOVE & 0x1)
544	if( DEBUG_FATFS_MOVE < cycle )
545	printk("\n[DBG] %s : access local FAT mapper\n"
546	"fat_mapper_cxy = %x / fat_mapper_ptr = %x / first_cluster_id = %d / index = %d\n",
547	__FUNCTION__ , fat_mapper_cxy , fat_mapper_ptr , first_cluster_id , index );
548	#endif
549	error = fatfs_get_cluster( fat_mapper_ptr,
550	first_cluster_id,
551	index,
552	&searched_cluster_id );
553	}
554	else // FAT mapper is remote
555	{
556
557	#if (DEBUG_FATFS_MOVE & 0x1)
558	if( DEBUG_FATFS_MOVE < cycle )
559	printk("\n[DBG] %s : access remote FAT mapper\n"
560	"fat_mapper_cxy = %x / fat_mapper_ptr = %x / first_cluster_id = %d / index = %d\n",
561	__FUNCTION__ , fat_mapper_cxy , fat_mapper_ptr , first_cluster_id , index );
562	#endif
563	rpc_fatfs_get_cluster_client( fat_mapper_cxy,
564	fat_mapper_ptr,
565	first_cluster_id,
566	index,
567	&searched_cluster_id,
568	&error );
569	}
570
571	if( error ) return EIO;
572	}
573
574	#if (DEBUG_FATFS_MOVE & 0x1)
575	if( DEBUG_FATFS_MOVE < cycle )
576	printk("\n[DBG] %s : access device for inode %x / cluster_id %d\n",
577	__FUNCTION__ , inode , searched_cluster_id );
578	#endif
579
580	// get lba from cluster_id
581	lba = fatfs_lba_from_cluster( fatfs_ctx , searched_cluster_id );
582
583	// access device
584	if( to_mapper ) error = dev_ioc_sync_read ( buffer , lba , count );
585	else error = dev_ioc_write( buffer , lba , count );
586
587	if( error ) return EIO;
588	}
589
590	#if DEBUG_FATFS_MOVE
591	cycle = (uint32_t)hal_get_cycles();
592	if( DEBUG_FATFS_MOVE < cycle )
593	printk("\n[DBG] %s : thread %x exit / page %d / inode %x / mapper %x / cycle %d\n",
594	__FUNCTION__ , CURRENT_THREAD , index , inode , mapper , cycle );
595	#endif
596
597	#if (DEBUG_FATFS_MOVE & 0x1)
598	if( DEBUG_FATFS_MOVE < cycle )
599	{
600	uint32_t * tab = (uint32_t *)buffer;
601	uint32_t line , word;
602	printk("\n***** %s : First 64 words of loaded page\n", __FUNCTION__ );
603	for( line = 0 ; line < 8 ; line++ )
604	{
605	printk("%X : ", line );
606	for( word = 0 ; word < 8 ; word++ ) printk("%X ", tab[(line<<3) + word] );
607	printk("\n");
608	}
609	}
610	#endif
611
612	return 0;
613
614	} // end fatfs_mapper_move_page()
615
616	/////////////////////////////////////////////////////
617	error_t fatfs_inode_load( vfs_inode_t * parent_inode,
618	char * name,
619	xptr_t child_inode_xp )
620	{
621	// Two embedded loops:
622	// - scan the parent mapper pages
623	// - scan the directory entries in each 4 Kbytes page
624
625	#if DEBUG_FATFS_LOAD
626	uint32_t cycle = (uint32_t)hal_get_cycles();
627	if( DEBUG_FATFS_LOAD < cycle )
628	printk("\n[DBG] %s : thread %x enter for child <%s> in parent inode %x / cycle %d\n",
629	__FUNCTION__ , CURRENT_THREAD , name , parent_inode , cycle );
630	#endif
631
632	mapper_t * mapper = parent_inode->mapper;
633
634	assert( (mapper != NULL) , "parent mapper undefined\n");
635
636	char cname[CONFIG_VFS_MAX_NAME_LENGTH]; // name extracter from each directory entry
637
638	char lfn1[16]; // buffer for one partial cname
639	char lfn2[16]; // buffer for one partial cname
640	char lfn3[16]; // buffer for one partial cname
641	page_t * page; // pointer on current page descriptor
642	uint8_t * base; // pointer on current page base
643	uint32_t offset = 0; // byte offset in page
644	uint32_t index = 0; // page index in mapper
645	uint32_t attr; // directory entry ATTR field
646	uint32_t ord; // directory entry ORD field
647	uint32_t seq; // sequence index
648	uint32_t lfn = 0; // LFN entries number
649	uint32_t size = 0; // searched file/dir size (bytes)
650	uint32_t cluster = 0; // searched file/dir cluster index
651	uint32_t is_dir = 0; // searched file/dir type
652	uint32_t dentry; // directory entry index
653	int32_t found = 0; // not found (0) / name found (1) / end of dir (-1)
654
655	// scan the parent directory mapper
656	while ( found == 0 )
657	{
658	// get one page
659	page = mapper_get_page( mapper , index );
660
661	assert( (page != NULL) , "bad parent mapper\n");
662
663	// get page base
664	xptr_t base_xp = ppm_page2base( XPTR( local_cxy , page ) );
665	base = (uint8_t *)GET_PTR( base_xp );
666
667	#if (DEBUG_FATFS_LOAD & 0x1)
668	if( DEBUG_FATFS_LOAD < cycle )
669	{
670	uint32_t * buf = (uint32_t *)base;
671	uint32_t line , word;
672	printk("\n***** %s : First 16 dentries for parent inode %x\n",
673	__FUNCTION__ , parent_inode );
674	for( line = 0 ; line < 16 ; line++ )
675	{
676	printk("%X : ", line );
677	for( word = 0 ; word < 8 ; word++ ) printk("%X ", buf[(line<<4) + word] );
678	printk("\n");
679	}
680	}
681	#endif
682	// scan this page until end of directory, end of page, or name found
683	while( (offset < 4096) && (found == 0) )
684	{
685	attr = fatfs_get_record( DIR_ATTR , base + offset , 0 );
686	ord = fatfs_get_record( LDIR_ORD , base + offset , 0 );
687
688	if (ord == NO_MORE_ENTRY) // no more entry => break
689	{
690	found = -1;
691	}
692	else if ( ord == FREE_ENTRY ) // free entry => skip
693	{
694	offset = offset + 32;
695	}
696	else if ( attr == ATTR_LONG_NAME_MASK ) // LFN entry => get partial cname
697	{
698	seq = ord & 0x3;
699	lfn = (seq > lfn) ? seq : lfn;
700	if ( seq == 1 ) fatfs_get_name_from_long( base + offset, lfn1 );
701	else if ( seq == 2 ) fatfs_get_name_from_long( base + offset, lfn2 );
702	else if ( seq == 3 ) fatfs_get_name_from_long( base + offset, lfn3 );
703	offset = offset + 32;
704	}
705	else // NORMAL entry
706	{
707	// build the extracted name
708	if ( lfn == 0 )
709	{
710	fatfs_get_name_from_short( base + offset , cname );
711	}
712	else if ( lfn == 1 )
713	{
714	strcpy( cname , lfn1 );
715	}
716	else if ( lfn == 2 )
717	{
718	strcpy( cname , lfn1 );
719	strcpy( cname + 13 , lfn2 );
720	}
721	else if ( lfn == 3 )
722	{
723	strcpy( cname , lfn1 );
724	strcpy( cname + 13 , lfn2 );
725	strcpy( cname + 26 , lfn3 );
726	}
727
728	// get dentry arguments if extracted cname == searched name
729	if ( strcmp( name , cname ) == 0 )
730	{
731	cluster = (fatfs_get_record( DIR_FST_CLUS_HI , base + offset , 1 ) << 16) \|
732	(fatfs_get_record( DIR_FST_CLUS_LO , base + offset , 1 ) ) ;
733	dentry = ((index<<12) + offset)>>5;
734	is_dir = ((attr & ATTR_DIRECTORY) == ATTR_DIRECTORY);
735	size = fatfs_get_record( DIR_FILE_SIZE , base + offset , 1 );
736	found = 1;
737	}
738	offset = offset + 32;
739	lfn = 0;
740	}
741	} // end loop on directory entries
742	index++;
743	offset = 0;
744	} // end loop on pages
745
746	// analyse the result of scan
747
748	if ( found == -1 ) // found end of directory => failure
749	{
750
751	#if DEBUG_FATFS_LOAD
752	cycle = (uint32_t)hal_get_cycles();
753	if( DEBUG_FATFS_LOAD < cycle )
754	printk("\n[DBG] %s : thread %x exit / child <%s> not found / cycle %d\n",
755	__FUNCTION__ , CURRENT_THREAD, name, cycle );
756	#endif
757
758	return ENOENT;
759	}
760	else // found searched child name
761	{
762	// get child inode cluster and local pointer
763	cxy_t child_cxy = GET_CXY( child_inode_xp );
764	vfs_inode_t * child_ptr = (vfs_inode_t *)GET_PTR( child_inode_xp );
765
766	// update the child inode "type", "size", and "extend" fields
767	vfs_inode_type_t type = (is_dir) ? INODE_TYPE_DIR : INODE_TYPE_FILE;
768
769	hal_remote_sw( XPTR( child_cxy , &child_ptr->type ) , type );
770	hal_remote_sw( XPTR( child_cxy , &child_ptr->size ) , size );
771	hal_remote_sw( XPTR( child_cxy , &child_ptr->extend ) , cluster );
772
773	#if DEBUG_FATFS_LOAD
774	cycle = (uint32_t)hal_get_cycles();
775	if( DEBUG_FATFS_LOAD < cycle )
776	printk("\n[DBG] %s : thread %x exit / child <%s> loaded / cycle %d\n",
777	__FUNCTION__ , CURRENT_THREAD, name, cycle );
778	#endif
779
780	return 0;
781	}
782	} // end fatfs_inode_load()

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source: trunk/kernel/fs/fatfs.c @ 507

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