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source: trunk/kernel/vfs/fatfs.c @ 378

Last change on this file since 378 was 367, checked in by alain, 7 years ago
Change Time unit from cycle to TICK (in millisecond). Fix several bugs in VFS.
File size: 26.2 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_types.h>
26	#include <hal_special.h>
27	#include <printk.h>
28	#include <kmem.h>
29	#include <ppm.h>
30	#include <vfs.h>
31	#include <string.h>
32	#include <rpc.h>
33	#include <mapper.h>
34	#include <cluster.h>
35	#include <dev_ioc.h>
36	#include <fatfs.h>
37
38
39	//////////////////////////////////////////////////////////////////////////////////////////
40	// Extern variables
41	//////////////////////////////////////////////////////////////////////////////////////////
42
43	extern vfs_ctx_t fs_context[FS_TYPES_NR]; // allocated in vfs.c file
44
45	extern remote_barrier_t global_barrier; // allocated in kernel_init.c
46
47	//////////////////////////////////////////////////////////////////////////////////////////
48	// FATFS specific and static functions
49	//////////////////////////////////////////////////////////////////////////////////////////
50
51	//////////////////////////////////////////////////////////////////////////////////////////
52	// These functions return the "offset" and "length" values of an
53	// [offset,length] constant defined in the fatfs.h file.
54	//////////////////////////////////////////////////////////////////////////////////////////
55
56	static inline int get_length( int offset , int length ) { return length; }
57
58	static inline int get_offset( int offset , int length ) { return offset; }
59
60
61	//////////////////////////////////////////////////////////////////////////////////////////
62	// This function returns the LBA of the first sector of a FAT cluster.
63	// This function can be called by any thread running in any cluster.
64	//////////////////////////////////////////////////////////////////////////////////////////
65	// @ ctx : pointer on FATFS context.
66	// @ cluster : cluster index in FATFS.
67	// @ return the lba value.
68	//////////////////////////////////////////////////////////////////////////////////////////
69	static inline uint32_t fatfs_lba_from_cluster( fatfs_ctx_t * ctx,
70	uint32_t cluster )
71	{
72	return (ctx->cluster_begin_lba + ((cluster - 2) << 3));
73	}
74
75	//////////////////////////////////////////////////////////////////////////////////////////
76	// This function return an integer record value (one, two, or four bytes)
77	// from a memory buffer, taking into account endianness.
78	//////////////////////////////////////////////////////////////////////////////////////////
79	// @ offset : first byte of record in buffer.
80	// @ size : record length in bytes (1/2/4).
81	// @ buffer : pointer on buffer base.
82	// @ little endian : the most significant byte has the highest address when true.
83	// @ return the integer value in a 32 bits word.
84	//////////////////////////////////////////////////////////////////////////////////////////
85	static uint32_t fatfs_get_record( uint32_t offset,
86	uint32_t size,
87	uint8_t * buffer,
88	uint32_t little_endian )
89	{
90	uint32_t n;
91	uint32_t res = 0;
92
93	if ( little_endian)
94	{
95	for( n = size ; n > 0 ; n-- ) res = (res<<8) \| buffer[offset+n-1];
96	}
97	else
98	{
99	for( n = 0 ; n < size ; n++ ) res = (res<<8) \| buffer[offset+n];
100	}
101	return res;
102
103	} // end fatfs_get_record()
104
105	//////////////////////////////////////////////////////////////////////////////////////////
106	// This static function retun in the <name> buffer a short name stored in
107	// a SFN FATFS directory entry.
108	/////////////////////////i////////////////////////////////////////////////////////////////
109	// @ buffer : pointer on buffer containing the directory entry.
110	// @ name : [out] buffer allocated by the caller.
111	//////////////////////////////////////////////////////////////////////////////////////////
112	static void fatfs_get_name_from_short( uint8_t * buffer,
113	char * name )
114	{
115	uint32_t i;
116	uint32_t j = 0;
117
118	// get name
119	for ( i = 0; i < 8 && buffer[i] != ' '; i++ )
120	{
121	name[j] = to_lower( buffer[i] );
122	j++;
123	}
124
125	// get extension
126	for ( i = 8; i < 8 + 3 && buffer[i] != ' '; i++ )
127	{
128	// we entered the loop so there is an extension. add the dot
129	if ( i == 8 )
130	{
131	name[j] = '.';
132	j++;
133	}
134
135	name[j] = to_lower( buffer[i] );
136	j++;
137	}
138
139	name[j] = '\0';
140	}
141
142	//////////////////////////////////////////////////////////////////////////////////////////
143	// This static function retun in the <name> buffer a partial name stored in
144	// a LFN FATFS directory entry.
145	/////////////////////////i////////////////////////////////////////////////////////////////
146	// @ buffer : pointer on buffer containing the directory entry.
147	// @ name : [out] buffer allocated by the caller.
148	//////////////////////////////////////////////////////////////////////////////////////////
149	static void fatfs_get_name_from_long( uint8_t * buffer,
150	char * name )
151	{
152	uint32_t name_offset = 0;
153	uint32_t buffer_offset = get_length(LDIR_ORD);
154	uint32_t l_name_1 = get_length(LDIR_NAME_1);
155	uint32_t l_name_2 = get_length(LDIR_NAME_2);
156	uint32_t l_name_3 = get_length(LDIR_NAME_3);
157	uint32_t l_attr = get_length(LDIR_ATTR);
158	uint32_t l_type = get_length(LDIR_TYPE);
159	uint32_t l_chksum = get_length(LDIR_CHKSUM);
160	uint32_t l_rsvd = get_length(LDIR_RSVD);
161
162	uint32_t j = 0;
163	uint32_t eof = 0;
164
165	while ( (buffer_offset != DIR_ENTRY_SIZE) && (!eof) )
166	{
167	while (j != l_name_1 && !eof )
168	{
169	if ( (buffer[buffer_offset] == 0x00) \|\|
170	(buffer[buffer_offset] == 0xFF) )
171	{
172	eof = 1;
173	continue;
174	}
175	name[name_offset] = buffer[buffer_offset];
176	buffer_offset += 2;
177	j += 2;
178	name_offset++;
179	}
180
181	buffer_offset += (l_attr + l_type + l_chksum);
182	j = 0;
183
184	while (j != l_name_2 && !eof )
185	{
186	if ( (buffer[buffer_offset] == 0x00) \|\|
187	(buffer[buffer_offset] == 0xFF) )
188	{
189	eof = 1;
190	continue;
191	}
192	name[name_offset] = buffer[buffer_offset];
193	buffer_offset += 2;
194	j += 2;
195	name_offset++;
196	}
197
198	buffer_offset += l_rsvd;
199	j = 0;
200
201	while (j != l_name_3 && !eof )
202	{
203	if ( (buffer[buffer_offset] == 0x00) \|\|
204	(buffer[buffer_offset] == 0xFF) )
205	{
206	eof = 1;
207	continue;
208	}
209	name[name_offset] = buffer[buffer_offset];
210	buffer_offset += 2;
211	j += 2;
212	name_offset++;
213	}
214	}
215	name[name_offset] = 0;
216
217	} // end get_name_from_long()
218
219
220	//////////////////////////////////////////////////////////////////////////////////////////
221	// FATFS specific but extern functions
222	//////////////////////////////////////////////////////////////////////////////////////////
223
224	//////////////////////////////////////////////////////////////////////////////////////////
225	void fatfs_ctx_display()
226	{
227	vfs_ctx_t * vfs_ctx = &fs_context[FS_TYPE_FATFS];
228	fatfs_ctx_t * fatfs_ctx = (fatfs_ctx_t *)vfs_ctx->extend;
229
230	printk("\n* FAT context *\n"
231	"- fat_sectors = %d\n"
232	"- sector size = %d\n"
233	"- cluster size = %d\n"
234	"- fat_first_lba = %d\n"
235	"- data_first_lba = %d\n"
236	"- root_dir_cluster = %d\n"
237	"- mapper_xp = %l\n",
238	fatfs_ctx->fat_sectors_count,
239	fatfs_ctx->bytes_per_sector,
240	fatfs_ctx->sectors_per_cluster * fatfs_ctx->bytes_per_sector,
241	fatfs_ctx->fat_begin_lba,
242	fatfs_ctx->cluster_begin_lba,
243	fatfs_ctx->root_dir_cluster,
244	fatfs_ctx->fat_mapper_xp );
245	}
246
247	/////////////////////////////////////////////
248	error_t fatfs_get_cluster( mapper_t * mapper,
249	uint32_t first_cluster_id,
250	uint32_t page_index,
251	uint32_t * searched_cluster_id )
252	{
253	page_t * current_page_desc; // pointer on current page descriptor
254	uint32_t * current_page_buffer; // pointer on current page (array of uint32_t)
255	uint32_t current_page_index; // index of current page in mapper
256	uint32_t current_page_offset; // offset of slot in current page
257	uint32_t page_count_in_file; // index of page in file (index in linked list)
258	uint32_t current_cluster_id; // content of current FAT slot
259
260	assert( (page_index > 0) , __FUNCTION__ , "no FAT access required for first page\n");
261
262	fatfs_dmsg("\n[INFO] %s : enters / mapper = %x / first_cluster_id = %d / page_index = %d\n",
263	__FUNCTION__ , first_cluster_id , page_index );
264
265	#if (CONFIG_FATFS_DEBUG > 1)
266	xptr_t base_xp = ppm_page2base( XPTR( local_cxy , mapper_get_page ( mapper , 0 ) ) );
267	uint32_t * buf = (uint32_t *)GET_PTR( base_xp );
268	uint32_t line , word;
269	printk("\n* FAT mapper content for first 256 entries *\n");
270	for( line = 0 ; line < 16 ; line++ )
271	{
272	printk("%X : ", line );
273	for( word = 0 ; word < 16 ; word++ ) printk("%X ", buf[(line<<4) + word] );
274	printk("\n");
275	}
276	#endif
277
278	// compute number of FAT slots per page
279	uint32_t slots_per_page = CONFIG_PPM_PAGE_SIZE >> 2;
280
281	// initialize loop variable
282	current_page_index = first_cluster_id / slots_per_page;
283	current_page_offset = first_cluster_id % slots_per_page;
284	page_count_in_file = 0;
285
286	// scan FAT (i.e. traverse FAT linked list)
287	while( page_count_in_file <= page_index )
288	{
289
290	fatfs_dmsg("\n[INFO] %s : page_index = %d / page_offset = %d / count = %d\n",
291	__FUNCTION__ , current_page_index , current_page_offset , page_count_in_file );
292
293	// get pointer on current page descriptor
294	current_page_desc = mapper_get_page( mapper , current_page_index );
295
296	if( current_page_desc == NULL ) return EIO;
297
298	// get pointer on buffer for current page
299	xptr_t base_xp = ppm_page2base( XPTR( local_cxy , current_page_desc ) );
300	current_page_buffer = (uint32_t *)GET_PTR( base_xp );
301
302	// get FAT slot content
303	current_cluster_id = current_page_buffer[current_page_offset];
304
305	// update loop variables
306	current_page_index = current_cluster_id / slots_per_page;
307	current_page_offset = current_cluster_id % slots_per_page;
308	page_count_in_file++;
309	}
310
311	fatfs_dmsg("\n[INFO] %s : exit / cluster_id = %d\n",
312	__FUNCTION__ , current_cluster_id );
313
314	*searched_cluster_id = current_cluster_id;
315	return 0;
316
317	} // end fatfs_get_cluster()
318
319
320
321	///////////////////////////////////////////////////////////////////////////////////////
322	// Generic API : the following functions are called by the kernel (VFS)
323	// and must be defined by all supported file systems.
324	///////////////////////////////////////////////////////////////////////////////////////
325
326	///////////////////////////////
327	fatfs_ctx_t * fatfs_ctx_alloc()
328	{
329	kmem_req_t req;
330	req.type = KMEM_FATFS_CTX;
331	req.size = sizeof(fatfs_ctx_t);
332	req.flags = AF_KERNEL \| AF_ZERO;
333
334	return (fatfs_ctx_t *)kmem_alloc( &req );
335	}
336
337	//////////////////////////////////////////////
338	void fatfs_ctx_init( fatfs_ctx_t * fatfs_ctx )
339	{
340	error_t error;
341	kmem_req_t req;
342	uint8_t * buffer;
343
344	fatfs_dmsg("\n[INFO] %s : enter for fatfs_ctx = %x\n",
345	__FUNCTION__ , fatfs_ctx );
346
347	assert( (fatfs_ctx != NULL) , __FUNCTION__ ,
348	"cannot allocate memory for FATFS context\n" );
349
350	// allocate a 512 bytes buffer to store the boot record
351	req.type = KMEM_512_BYTES;
352	req.flags = AF_KERNEL \| AF_ZERO;
353	buffer = (uint8_t *)kmem_alloc( &req );
354
355	assert( (buffer != NULL) , __FUNCTION__ ,
356	"cannot allocate memory for 512 bytes buffer\n" );
357
358	fatfs_dmsg("\n[INFO] %s : allocated 512 bytes buffer\n", __FUNCTION__ );
359
360	// load the boot record from device
361	// using a synchronous access to IOC device
362	error = dev_ioc_sync_read( buffer , 0 , 1 );
363
364	fatfs_dmsg("\n[INFO] %s : buffer loaded\n", __FUNCTION__ );
365
366	assert( (error == 0) , __FUNCTION__ ,
367	"cannot access boot record\n" );
368
369	#if (CONFIG_FATFS_DEBUG > 1)
370	uint32_t line;
371	uint32_t byte = 0;
372	printk("\n***** FAT boot record\n" );
373	for ( line = 0 ; line < 32 ; line++ )
374	{
375	printk(" %X \| %x %x %x %x %x %x %x %x %x %x %x %x %x %x %x %x \|\n",
376	byte,
377	buffer[byte+ 0],buffer[byte+ 1],buffer[byte+ 2],buffer[byte+ 3],
378	buffer[byte+ 4],buffer[byte+ 5],buffer[byte+ 6],buffer[byte+ 7],
379	buffer[byte+ 8],buffer[byte+ 9],buffer[byte+10],buffer[byte+11],
380	buffer[byte+12],buffer[byte+13],buffer[byte+14],buffer[byte+15] );
381
382	byte += 16;
383	}
384	#endif
385
386	// check sector size from boot record
387	uint32_t sector_size = fatfs_get_record( BPB_BYTSPERSEC , buffer , 1 );
388
389	assert( (sector_size == 512) , __FUNCTION__ ,
390	"sector size must be 512 bytes\n" );
391
392	// check cluster size from boot record
393	uint32_t nb_sectors = fatfs_get_record( BPB_SECPERCLUS , buffer , 1 );
394
395	assert( (nb_sectors == 8) , __FUNCTION__ ,
396	"cluster size must be 8 sectors\n" );
397
398	// check number of FAT copies from boot record
399	uint32_t nb_fats = fatfs_get_record( BPB_NUMFATS , buffer , 1 );
400
401	assert( (nb_fats == 1) , __FUNCTION__ ,
402	"number of FAT copies must be 1\n" );
403
404	// get & check number of sectors in FAT from boot record
405	uint32_t fat_sectors = fatfs_get_record( BPB_FAT32_FATSZ32 , buffer , 1 );
406
407	assert( ((fat_sectors & 0xF) == 0) , __FUNCTION__ ,
408	"FAT not multiple of 16 sectors\n");
409
410	// get and check root cluster from boot record
411	uint32_t root_cluster = fatfs_get_record( BPB_FAT32_ROOTCLUS , buffer , 1 );
412
413	assert( (root_cluster == 2) , __FUNCTION__ ,
414	"root cluster index must be 2\n");
415
416	// get FAT lba from boot record
417	uint32_t fat_lba = fatfs_get_record( BPB_RSVDSECCNT , buffer , 1 );
418
419	// release the 512 bytes buffer
420	req.type = KMEM_512_BYTES;
421	req.ptr = buffer;
422	kmem_free( &req );
423
424	fatfs_dmsg("\n[INFO] %s : boot record read & released\n",
425	__FUNCTION__ );
426
427	// allocate a mapper for the FAT itself
428	mapper_t * fat_mapper = mapper_create( FS_TYPE_FATFS );
429
430	assert( (fat_mapper != NULL) , __FUNCTION__ , "no memory for FAT mapper" );
431
432	// WARNING : the inode field MUST be NULL for the FAT mapper
433	fat_mapper->inode = NULL;
434
435	// initialize the FATFS context
436	fatfs_ctx->fat_begin_lba = fat_lba;
437	fatfs_ctx->fat_sectors_count = fat_sectors;
438	fatfs_ctx->bytes_per_sector = sector_size;
439	fatfs_ctx->sectors_per_cluster = nb_sectors;
440	fatfs_ctx->cluster_begin_lba = fat_lba + fat_sectors;
441	fatfs_ctx->root_dir_cluster = 2;
442	fatfs_ctx->last_allocated_sector = 0; // TODO ???
443	fatfs_ctx->last_allocated_index = 0; // TODO ???
444	fatfs_ctx->fat_mapper_xp = XPTR( local_cxy , fat_mapper );
445
446	fatfs_dmsg("\n[INFO] %s : exit for fatfs_ctx = %x\n",
447	__FUNCTION__ , fatfs_ctx );
448
449	} // end fatfs_ctx_init()
450
451	/////////////////////////////////////////////////
452	void fatfs_ctx_destroy( fatfs_ctx_t * fatfs_ctx )
453	{
454	kmem_req_t req;
455	req.type = KMEM_FATFS_CTX;
456	req.ptr = fatfs_ctx;
457	kmem_free( &req );
458	}
459
460	//////////////////////////////////////////////
461	error_t fatfs_mapper_move_page( page_t * page,
462	bool_t to_mapper )
463	{
464	error_t error;
465
466	// get pointer on source mapper and page index from page descriptor
467	mapper_t * mapper = page->mapper;
468	uint32_t index = page->index;
469
470	// get VFS inode pointer from mapper
471	vfs_inode_t * inode = mapper->inode;
472
473	fatfs_dmsg("\n[INFO] %s : enter for inode %x / page_index = %d / mapper = %x\n",
474	__FUNCTION__ , inode , index , mapper );
475
476	// get memory buffer base address
477	xptr_t base_xp = ppm_page2base( XPTR( local_cxy , page ) );
478	uint8_t * buffer = (uint8_t *)GET_PTR( base_xp );
479
480	// get number of sectors from FATFS context
481	fatfs_ctx_t * fatfs_ctx = (fatfs_ctx_t *)fs_context[FS_TYPE_FATFS].extend;
482	uint32_t count = fatfs_ctx->sectors_per_cluster;
483
484	// analyse the mapper type : FAT or normal inode
485	if( inode == NULL ) // it is the FAT mapper
486	{
487	// get lba from page index
488	uint32_t lba = fatfs_ctx->fat_begin_lba + (count * index);
489
490	fatfs_dmsg("\n[INFO] %s : for FAT / lba = %d\n",
491	__FUNCTION__ , lba );
492
493	// access device
494	if( to_mapper ) error = dev_ioc_sync_read ( buffer , lba , count );
495	else error = dev_ioc_write( buffer , lba , count );
496
497	if( error ) return EIO;
498
499	fatfs_dmsg("\n[INFO] %s : exit for FAT / page_index = %d / mapper = %x\n",
500	__FUNCTION__ , index , mapper );
501	}
502	else // it is a normal inode mapper
503	{
504	uint32_t searched_cluster_id;
505
506	// get first_cluster_id from inode extension
507	uint32_t first_cluster_id = (uint32_t)(intptr_t)inode->extend;
508
509	fatfs_dmsg("\n[INFO] %s : for inode %x / first_cluster_id = %d\n",
510	__FUNCTION__ , inode , first_cluster_id );
511
512	// compute cluster_id
513	if( index == 0 ) // no need to access FAT mapper
514	{
515	searched_cluster_id = first_cluster_id;
516	}
517	else // FAT mapper access required
518	{
519	// get cluster and local pointer on FAT mapper
520	xptr_t fat_mapper_xp = fatfs_ctx->fat_mapper_xp;
521	cxy_t fat_mapper_cxy = GET_CXY( fat_mapper_xp );
522	mapper_t * fat_mapper_ptr = (mapper_t *)GET_PTR( fat_mapper_xp );
523
524	// access FAT mapper
525	if( fat_mapper_cxy == local_cxy ) // FAT mapper is local
526	{
527	error = fatfs_get_cluster( fat_mapper_ptr,
528	first_cluster_id,
529	index,
530	&searched_cluster_id );
531	}
532	else // FAT mapper is remote
533	{
534	rpc_fatfs_get_cluster_client( fat_mapper_cxy,
535	fat_mapper_ptr,
536	first_cluster_id,
537	index,
538	&searched_cluster_id,
539	&error );
540	}
541
542	if( error ) return EIO;
543	}
544
545	// get lba from cluster_id
546	uint32_t lba = fatfs_lba_from_cluster( fatfs_ctx , searched_cluster_id );
547
548	fatfs_dmsg("\n[INFO] %s : for inode %x / page = %d / cluster_id = %d / lba = %x\n",
549	__FUNCTION__ , inode , index , searched_cluster_id , lba );
550
551	// access device
552	if( to_mapper ) error = dev_ioc_sync_read ( buffer , lba , count );
553	else error = dev_ioc_write( buffer , lba , count );
554
555	if( error ) return EIO;
556
557	fatfs_dmsg("\n[INFO] %s : exit for inode %x / page_index = %d / mapper = %x\n",
558	__FUNCTION__ , inode , index , mapper );
559	}
560
561	return 0;
562
563	} // end fatfs_mapper_move_page()
564
565	/////////////////////////////////////////////////////
566	error_t fatfs_inode_load( vfs_inode_t * parent_inode,
567	char * name,
568	xptr_t child_inode_xp )
569	{
570	// Two embedded loops:
571	// - scan the parent mapper pages
572	// - scan the directory entries in each 4 Kbytes page
573
574	fatfs_dmsg("\n[INFO] %s : enter for child <%s> in parent inode %l\n",
575	__FUNCTION__ , name , XPTR( local_cxy , parent_inode ) );
576
577	mapper_t * mapper = parent_inode->mapper;
578
579	assert( (mapper != NULL) , __FUNCTION__ , "parent mapper undefined\n");
580
581	char cname[CONFIG_VFS_MAX_NAME_LENGTH]; // name extracter from each directory entry
582
583	char lfn1[16]; // buffer for one partial cname
584	char lfn2[16]; // buffer for one partial cname
585	char lfn3[16]; // buffer for one partial cname
586	page_t * page; // pointer on current page descriptor
587	uint8_t * base; // pointer on current page base
588	uint32_t offset = 0; // byte offset in page
589	uint32_t index = 0; // page index in mapper
590	uint32_t attr; // directory entry ATTR field
591	uint32_t ord; // directory entry ORD field
592	uint32_t seq; // sequence index
593	uint32_t lfn = 0; // LFN entries number
594	uint32_t size = 0; // searched file/dir size (bytes)
595	uint32_t cluster = 0; // searched file/dir cluster index
596	uint32_t is_dir = 0; // searched file/dir type
597	uint32_t dentry; // directory entry index
598	int32_t found = 0; // not found (0) / name found (1) / end of dir (-1)
599
600	// scan the parent directory mapper
601	while ( found == 0 )
602	{
603	// get one page
604	page = mapper_get_page( mapper , index );
605
606	assert( (page != NULL) , __FUNCTION__ , "bad parent mapper\n");
607
608	// get page base
609	xptr_t base_xp = ppm_page2base( XPTR( local_cxy , page ) );
610	base = (uint8_t *)GET_PTR( base_xp );
611
612	#if (CONFIG_FATFS_DEBUG > 1)
613	uint32_t * buf = (uint32_t *)base;
614	uint32_t line , word;
615	printk("\n***** first 16 dir entries for parent inode %x\n", parent_inode );
616	for( line = 0 ; line < 16 ; line++ )
617	{
618	printk("%X : ", line );
619	for( word = 0 ; word < 8 ; word++ ) printk("%X ", buf[(line<<4) + word] );
620	printk("\n");
621	}
622	#endif
623
624
625	// scan this page until end of directory, end of page, or name found
626	while( (offset < 4096) && (found == 0) )
627	{
628	attr = fatfs_get_record( DIR_ATTR , base + offset , 0 );
629	ord = fatfs_get_record( LDIR_ORD , base + offset , 0 );
630
631	if (ord == NO_MORE_ENTRY) // no more entry => break
632	{
633	found = -1;
634	}
635	else if ( ord == FREE_ENTRY ) // free entry => skip
636	{
637	offset = offset + 32;
638	}
639	else if ( attr == ATTR_LONG_NAME_MASK ) // LFN entry => get partial cname
640	{
641	seq = ord & 0x3;
642	lfn = (seq > lfn) ? seq : lfn;
643	if ( seq == 1 ) fatfs_get_name_from_long( base + offset, lfn1 );
644	else if ( seq == 2 ) fatfs_get_name_from_long( base + offset, lfn2 );
645	else if ( seq == 3 ) fatfs_get_name_from_long( base + offset, lfn3 );
646	offset = offset + 32;
647	}
648	else // NORMAL entry
649	{
650	// build the extracted name
651	if ( lfn == 0 )
652	{
653	fatfs_get_name_from_short( base + offset , cname );
654	}
655	else if ( lfn == 1 )
656	{
657	strcpy( cname , lfn1 );
658	}
659	else if ( lfn == 2 )
660	{
661	strcpy( cname , lfn1 );
662	strcpy( cname + 13 , lfn2 );
663	}
664	else if ( lfn == 3 )
665	{
666	strcpy( cname , lfn1 );
667	strcpy( cname + 13 , lfn2 );
668	strcpy( cname + 26 , lfn3 );
669	}
670
671	// get dentry arguments if extracted cname == searched name
672	if ( strcmp( name , cname ) == 0 )
673	{
674	cluster = (fatfs_get_record( DIR_FST_CLUS_HI , base + offset , 1 ) << 16) \|
675	(fatfs_get_record( DIR_FST_CLUS_LO , base + offset , 1 ) ) ;
676	dentry = ((index<<12) + offset)>>5;
677	is_dir = ((attr & ATTR_DIRECTORY) == ATTR_DIRECTORY);
678	size = fatfs_get_record( DIR_FILE_SIZE , base + offset , 1 );
679	found = 1;
680	}
681	offset = offset + 32;
682	lfn = 0;
683	}
684	} // end loop on directory entries
685	index++;
686	offset = 0;
687	} // end loop on pages
688
689	// analyse the result of scan
690
691	if ( found == -1 ) // found end of directory => failure
692	{
693	fatfs_dmsg("\n[INFO] %s : exit / child <%s> not found in parent inode %l\n",
694	__FUNCTION__ , name , XPTR( local_cxy , parent_inode ) );
695
696	return ENOENT;
697	}
698	else // found searched child name
699	{
700	// get child inode cluster and local pointer
701	cxy_t child_cxy = GET_CXY( child_inode_xp );
702	vfs_inode_t * child_ptr = (vfs_inode_t *)GET_PTR( child_inode_xp );
703
704	// update the child inode "type", "size", and "extend" fields
705	vfs_inode_type_t type = (is_dir) ? INODE_TYPE_DIR : INODE_TYPE_FILE;
706
707	hal_remote_sw( XPTR( child_cxy , &child_ptr->type ) , type );
708	hal_remote_sw( XPTR( child_cxy , &child_ptr->size ) , size );
709	hal_remote_sw( XPTR( child_cxy , &child_ptr->extend ) , cluster );
710
711	fatfs_dmsg("\n[INFO] %s : exit / child <%s> found in parent inode %l\n",
712	__FUNCTION__ , name , XPTR( local_cxy , parent_inode ) );
713
714	return 0;
715	}
716	} // end fatfs_inode_load()

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