WebSVN – Kolibri OS – Blame – /kernel/trunk/fs/ext2/ext2.inc

Rev	Author	Line No.	Line
3935	shikhin	1	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		2	;; ;;
		3	;; Contains ext2 structures, and macros. ;;
		4	;; ;;
		5	;; Copyright (C) KolibriOS team 2004-2013. All rights reserved. ;;
		6	;; Distributed under the terms of the new BSD license. ;;
		7	;; ;;
		8	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		9
		10	; Recommended move to some kernel-wide bitmap handling code (with a bit of abstraction, of course).
		11
		12	;---------------------------------------------------------------------
		13	; Clears a bit.
		14	; Input: eax = index into bitmap.
		15	; [EXTFS.ext2_save_block] = address of bitmap.
		16	; ebp = address of EXTFS.
		17	; Output: Bit cleared.
		18	; eax = non-zero, if already cleared.
		19	;---------------------------------------------------------------------
		20	bitmap_clear_bit:
		21	push ebx ecx edx
		22
		23	xor edx, edx
		24	mov ecx, 8
		25	div ecx
		26
		27	add eax, [ebp + EXTFS.ext2_save_block]
		28
		29	; Get the mask.
		30	mov ebx, 1
		31	mov ecx, edx
		32	shl ebx, cl
		33
		34	test [eax], ebx
		35	jz .cleared
		36
		37	not ebx
		38	and [eax], ebx
		39
		40	xor eax, eax
		41	.return:
		42	pop edx ecx ebx
		43	ret
		44
		45	; Already cleared.
		46	.cleared:
		47	xor eax, eax
		48	not eax
		49	jmp .return
		50
		51	;---------------------------------------------------------------------
		52	; Finds free bit in the bitmap.
		53	; Input: ecx = number of bits in the bitmap.
		54	; [EXTFS.ext2_save_block] = address of bitmap.
		55	; ebp = address of EXTFS.
		56	; Output: eax = index of free bit in the bitmap; marked set.
		57	; 0xFFFFFFFF if no free bit found.
		58	;---------------------------------------------------------------------
		59	ext2_find_free_bit:
		60	bitmap_find_free_bit:
		61	push esi ebx ecx edx
		62	mov esi, [ebp + EXTFS.ext2_save_block]
		63
		64	; Get total DWORDS in eax; total bits in last dword, if any, in edx.
		65	xor edx, edx
		66	mov eax, ecx
		67	mov ecx, 32
		68	div ecx
		69
		70	mov ecx, eax
		71	xor eax, eax
		72	push edx
		73
		74	test ecx, ecx
		75	jz .last_bits
		76
		77	; Check in the DWORDS.
		78	.dwords:
		79	mov ebx, [esi]
		80	not ebx
		81
		82	bsf edx, ebx
		83
		84	; If 0, then the original value would be 0xFFFFFFFF, hence no free bits.
		85	jz @F
		86
		87	; We found the value. Let's return with it.
		88	add esp, 4
		89	add eax, edx
		90	jmp .return
		91
		92	@@:
		93	add esi, 4
		94	add eax, 32
		95	loop .dwords
		96
		97	.last_bits:
		98	; Check in the last few bits.
		99	pop ecx
		100	test ecx, ecx
		101	jz @F
		102
		103	mov ebx, [esi]
		104	not ebx
		105	bsf ebx, edx
		106
		107	; If 0, no free bits.
		108	jz @F
		109
		110	; If free bit is greater than the last known bit, then error.
		111	cmp edx, ecx
		112	jg @F
		113
		114	add eax, edx
		115	jmp .return
		116
		117	@@:
		118	; Didn't find any free bits.
		119	xor eax, eax
		120	not eax
		121	jmp @F
		122
		123	.return:
		124	mov ecx, edx
		125	mov edx, 1
		126	shl edx, cl
		127	or [esi], edx
		128
		129	@@:
		130	pop edx ecx ebx esi
		131	ret
		132
		133	; Recommended move to some kernel-wide string handling code.
		134	;---------------------------------------------------------------------
		135	; Find the length of a string.
		136	; Input: esi = source.
		137	; Output: length in ecx
		138	;---------------------------------------------------------------------
		139	strlen:
		140	push eax esi
		141	xor ecx, ecx
		142
		143	@@:
		144	lodsb
		145	test al, al
		146	jz .ret
		147
		148	inc ecx
		149	jmp @B
		150
		151	.ret:
		152	pop esi eax
		153	ret
		154
		155	;---------------------------------------------------------------------
		156	; Convert UTF-8 string to ASCII-string (codepage 866)
		157	; Input: esi = source.
		158	; edi = buffer.
		159	; ecx = length of source.
		160	; Output: destroys eax, esi, edi
		161	;---------------------------------------------------------------------
		162	utf8_to_cp866:
		163	; Check for zero-length string.
		164	jecxz .return
		165
		166	.start:
		167	lodsw
		168	cmp al, 0x80
		169	jb .ascii
		170
		171	xchg al, ah ; Big-endian.
		172	cmp ax, 0xd080
		173	jz .yo1
		174
		175	cmp ax, 0xd191
		176	jz .yo2
		177
		178	cmp ax, 0xd090
		179	jb .unk
		180
		181	cmp ax, 0xd180
		182	jb .rus1
		183
		184	cmp ax, 0xd190
		185	jb .rus2
		186
		187	.unk:
		188	mov al, '_'
		189	jmp .doit
		190
		191	.yo1:
		192	mov al, 0xf0 ; Ё capital.
		193	jmp .doit
		194
		195	.yo2:
		196	mov al, 0xf1 ; ё small.
		197	jmp .doit
		198
		199	.rus1:
		200	sub ax, 0xd090 - 0x80
		201	jmp .doit
		202
		203	.rus2:
		204	sub ax, 0xd18f - 0xEF
		205
		206	.doit:
		207	stosb
		208	sub ecx, 2
		209	ja .start
		210	ret
		211
		212	.ascii:
		213	stosb
		214	dec esi
		215	dec ecx
		216	jnz .start
		217
		218	.return:
		219	ret
		220
		221	; Recommended move to some kernel-wide time handling code.
		222
		223	; Total cumulative seconds till each month.
		224	cumulative_seconds_in_month:
		225	.january: dd 0 * (60 * 60 * 24)
		226	.february: dd 31 * (60 * 60 * 24)
		227	.march: dd 59 * (60 * 60 * 24)
		228	.april: dd 90 * (60 * 60 * 24)
		229	.may: dd 120 * (60 * 60 * 24)
		230	.june: dd 151 * (60 * 60 * 24)
		231	.july: dd 181 * (60 * 60 * 24)
		232	.august: dd 212 * (60 * 60 * 24)
		233	.september: dd 243 * (60 * 60 * 24)
		234	.october: dd 273 * (60 * 60 * 24)
		235	.november: dd 304 * (60 * 60 * 24)
		236	.december: dd 334 * (60 * 60 * 24)
		237
		238	current_bdfe_time:
		239	dd 0
		240	current_bdfe_date:
		241	dd 0
		242
		243	;---------------------------------------------------------------------
		244	; Stores current unix time.
		245	; Input: edi = buffer to output Unix time.
		246	;---------------------------------------------------------------------
		247	current_unix_time:
		248	push eax esi
		249	mov esi, current_bdfe_time
		250
		251	; Just a small observation:
		252	; The CMOS is a pretty bad source to get time from. One shouldn't rely on it,
		253	; since it messes up the time by tiny bits. Of course, this is all technical,
		254	; but one can look it up on the osdev wiki. What is better is to get the time
		255	; from CMOS during boot, then update system time using a more accurate timer.
		256	; I'll probably add that after the Summer of Code, so TODO! TODO! TODO!.
		257
		258	; Get time from CMOS.
		259	; Seconds.
		260	mov al, 0x00
		261	out 0x70, al
		262	in al, 0x71
		263	call bcd2bin
		264	mov [esi + 0], al
		265
		266	; Minute.
		267	mov al, 0x02
		268	out 0x70, al
		269	in al, 0x71
		270	call bcd2bin
		271	mov [esi + 1], al
		272
		273	; Hour.
		274	mov al, 0x04
		275	out 0x70, al
		276	in al, 0x71
		277	call bcd2bin
		278	mov [esi + 2], al
		279
		280	; Get date.
		281
		282	; Day.
		283	mov al, 0x7
		284	out 0x70, al
		285	in al, 0x71
		286	call bcd2bin
		287	mov [esi + 4], al
		288
		289	; Month.
		290	mov al, 0x8
		291	out 0x70, al
		292	in al, 0x71
		293	call bcd2bin
		294	mov [esi + 5], al
		295
		296	; Year.
		297	mov al, 0x9
		298	out 0x70, al
		299	in al, 0x71
		300	call bcd2bin
		301	add ax, 2000 ; CMOS only returns last two digits.
		302	; Note that everywhere in KolibriOS this is used.
		303	; This is hacky, since the RTC can be incorrectly set
		304	; to something before 2000.
		305	mov [esi + 6], ax
		306
		307	call bdfe_to_unix_time
		308	pop esi eax
		309	ret
		310
		311	;---------------------------------------------------------------------
		312	; Convert time+date from BDFE to Unix time.
		313	; Input: esi = pointer to BDFE time+date.
		314	; edi = buffer to output Unix time.
		315	;---------------------------------------------------------------------
		316	bdfe_to_unix_time:
		317	push eax ebx ecx edx
		318	mov dword[edi], 0x00000000
		319
		320	; The minimum representable time is 1901-12-13.
		321	cmp word[esi + 6], 1901
		322	jb .ret
		323	jg .max
		324
		325	cmp byte[esi + 5], 12
		326	jb .ret
		327
		328	cmp byte[esi + 4], 13
		329	jbe .ret
		330	jg .convert
		331
		332	; Check if it is more than the maximum representable time.
		333	.max:
		334	; The maximum representable time is 2038-01-19.
		335	cmp word[esi + 6], 2038
		336	jg .ret
		337	jb .convert
		338
		339	cmp byte[esi + 5], 1
		340	jg .ret
		341
		342	cmp byte[esi + 4], 19
		343	jge .ret
		344
		345	; Convert the time.
		346	.convert:
		347	; Get if current year is leap year in ECX.
		348	xor ecx, ecx
		349	mov ebx, 4
		350	xor edx, edx
		351
		352	cmp word[esi + 6], 1970
		353	jb .negative
		354
		355	movzx eax, word[esi + 6] ; Year.
		356	cmp byte[esi + 5], 3 ; If the month is less than March, than that year doesn't matter.
		357	jge @F
		358
		359	test eax, 3
		360	; Not a leap year.
		361	jnz @F
		362
		363	inc ecx
		364	@@:
		365	; Number of leap years between two years = ((end date - 1)/4) - (1970/4)
		366	dec eax
		367	div ebx
		368	sub eax, 1970/4
		369
		370	; EAX is the number of leap years.
		371	add eax, ecx
		372	mov ecx, (60 * 60 * 24) ; Seconds in a day.
		373	mul ecx
		374
		375	; Account for leap years, i.e., one day extra for each.
		376	add [edi], eax
		377
		378	; Get total days in EAX.
		379	movzx eax, byte[esi + 4]
		380	dec eax
		381	mul ecx
		382
		383	; Account for days.
		384	add [edi], eax
		385
		386	; Account for month.
		387	movzx eax, byte[esi + 5]
		388	dec eax
		389	mov eax, [cumulative_seconds_in_month + (eax * 4)]
		390	add [edi], eax
		391
		392	; Account for year.
		393	movzx eax, word[esi + 6]
		394	sub eax, 1970
		395	mov ecx, (60 * 60 * 24) * 365 ; Seconds in a year.
		396	mul ecx
		397	add [edi], eax
		398
		399	; Seconds.
		400	movzx eax, byte[esi + 0]
		401	add [edi], eax
		402
		403	; Minutes.
		404	movzx eax, byte[esi + 1]
		405	mov ecx, 60
		406	mul ecx
		407	add [edi], eax
		408
		409	; Hours.
		410	movzx eax, byte[esi + 2]
		411	mov ecx, (60 * 60)
		412	mul ecx
		413	add [edi], eax
		414
		415	; The time wanted is before the epoch; handle it here.
		416	.negative:
		417	; TODO.
		418
		419	.ret:
		420	pop edx ecx ebx eax
		421	ret
		422
		423	; Recommended move to some kernel-wide alloc handling code.
		424	macro KERNEL_ALLOC store, label
		425	{
		426	call kernel_alloc
		427	mov store, eax
		428	test eax, eax
		429	jz label
		430	}
		431
		432	macro KERNEL_FREE data, label
		433	{
		434	cmp data, 0
		435	jz label
		436	push data
		437	call kernel_free
		438	}
		439
		440	struct EXTFS PARTITION
		441	lock MUTEX
		442	partition_flags dd ?
		443	log_block_size dd ?
		444	block_size dd ?
		445	count_block_in_block dd ?
		446	blocks_per_group dd ?
		447	global_desc_table dd ?
		448	root_inode dd ? ; Pointer to root inode in memory.
		449	inode_size dd ?
		450	count_pointer_in_block dd ? ; (block_size / 4)
		451	count_pointer_in_block_square dd ? ; (block_size / 4)**2
		452	ext2_save_block dd ? ; Block for 1 global procedure.
		453	ext2_temp_block dd ? ; Block for small procedures.
		454	ext2_save_inode dd ? ; inode for global procedures.
		455	ext2_temp_inode dd ? ; inode for small procedures.
		456	groups_count dd ?
		457	superblock rd 1024/4
		458	ends
		459
		460	; EXT2 revisions.
		461	EXT2_GOOD_OLD_REV = 0
		462
		463	; For fs_type.
		464	FS_TYPE_UNDEFINED = 0
		465	FS_TYPE_EXT = 2
		466
		467	; Some set inodes.
		468	EXT2_BAD_INO = 1
		469	EXT2_ROOT_INO = 2
		470	EXT2_ACL_IDX_INO = 3
		471	EXT2_ACL_DATA_INO = 4
		472	EXT2_BOOT_LOADER_INO = 5
		473	EXT2_UNDEL_DIR_INO = 6
		474
		475	; EXT2_SUPER_MAGIC.
		476	EXT2_SUPER_MAGIC = 0xEF53
		477	EXT2_VALID_FS = 1
		478
		479	; Flags defining i_mode values.
		480	EXT2_S_IFMT = 0xF000 ; Mask for file type.
		481
		482	EXT2_S_IFREG = 0x8000 ; Regular file.
		483	EXT2_S_IFDIR = 0x4000 ; Directory.
		484
		485	; File type defining values in directory entry.
		486	EXT2_FT_REG_FILE = 1 ; Regular file.
		487	EXT2_FT_DIR = 2 ; Directory.
		488
		489	; Flags used by KolibriOS.
		490	FS_FT_HIDDEN = 2
		491	FS_FT_DIR = 0x10 ; Directory.
		492
		493	; ext2 partition flags.
		494	EXT2_RO = 0x01
		495
		496	FS_FT_ASCII = 0 ; Name in ASCII.
		497	FS_FT_UNICODE = 1 ; Name in Unicode.
		498
		499	EXT2_FEATURE_INCOMPAT_FILETYPE = 0x0002 ; Have file type in directory entry.
		500	EXT4_FEATURE_INCOMPAT_EXTENTS = 0x0040 ; Extents.
		501	EXT4_FEATURE_INCOMPAT_FLEX_BG = 0x0200 ; Flexible block groups.
		502
		503	EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER = 0x0001 ; Sparse Superblock
		504	EXT2_FEATURE_RO_COMPAT_LARGE_FILE = 0x0002 ; Large file support (64-bit file size)
		505
		506	; Implemented ext[2,3,4] features.
		507	EXT4_FEATURE_INCOMPAT_SUPP = EXT2_FEATURE_INCOMPAT_FILETYPE \
		508	or EXT4_FEATURE_INCOMPAT_EXTENTS \
		509	or EXT4_FEATURE_INCOMPAT_FLEX_BG
		510
		511	; Implemented features which otherwise require "read-only" mount.
		512	EXT2_FEATURE_RO_COMPAT_SUPP = EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER \
		513	or EXT2_FEATURE_RO_COMPAT_LARGE_FILE
		514
		515	; ext4 features not support for write.
		516	EXT4_FEATURE_INCOMPAT_W_NOT_SUPP = EXT4_FEATURE_INCOMPAT_EXTENTS \
		517	or EXT4_FEATURE_INCOMPAT_FLEX_BG
		518
		519	; Flags specified in i_flags.
		520	EXT2_EXTENTS_FL = 0x00080000 ; Extents.
		521
		522	struct EXT2_INODE_STRUC
		523	i_mode dw ?
		524	i_uid dw ?
		525	i_size dd ?
		526	i_atime dd ?
		527	i_ctime dd ?
		528	i_mtime dd ?
		529	i_dtime dd ?
		530	i_gid dw ?
		531	i_links_count dw ?
		532	i_blocks dd ?
		533	i_flags dd ?
		534	i_osd1 dd ?
		535	i_block rd 15
		536	i_generation dd ?
		537	i_file_acl dd ?
		538	i_dir_acl dd ?
		539	i_faddr dd ?
		540	i_osd2 dd ? ; 12 bytes.
		541	ends
		542
		543	struct EXT2_DIR_STRUC
		544	inode dd ?
		545	rec_len dw ?
		546	name_len db ?
		547	file_type db ?
		548	name db ? ; 255 (max) bytes.
		549	ends
		550
		551	struct EXT2_BLOCK_GROUP_DESC
		552	block_bitmap dd ? ; +0
		553	inode_bitmap dd ? ; +4
		554	inode_table dd ? ; +8
		555	free_blocks_count dw ? ; +12
		556	free_inodes_count dw ? ; +14
		557	used_dirs_count dw ? ; +16
		558	pad dw ? ; +18
		559	reserved rb 12 ; +20
		560	ends
		561
		562	struct EXT2_SB_STRUC
		563	inodes_count dd ? ; +0
		564	blocks_count dd ? ; +4
		565	r_block_count dd ? ; +8
		566	free_block_count dd ? ; +12
		567	free_inodes_count dd ? ; +16
		568	first_data_block dd ? ; +20
		569	log_block_size dd ? ; +24
		570	log_frag_size dd ? ; +28
		571	blocks_per_group dd ? ; +32
		572	frags_per_group dd ? ; +36
		573	inodes_per_group dd ? ; +40
		574	mtime dd ? ; +44
		575	wtime dd ? ; +48
		576	mnt_count dw ? ; +52
		577	max_mnt_count dw ? ; +54
		578	magic dw ? ; +56
		579	state dw ? ; +58
		580	errors dw ? ; +60
		581	minor_rev_level dw ? ; +62
		582	lastcheck dd ? ; +64
		583	check_intervals dd ? ; +68
		584	creator_os dd ? ; +72
		585	rev_level dd ? ; +76
		586	def_resuid dw ? ; +80
		587	def_resgid dw ? ; +82
		588	first_ino dd ? ; +84
		589	inode_size dw ? ; +88
		590	block_group_nr dw ? ; +90
		591	feature_compat dd ? ; +92
		592	feature_incompat dd ? ; +96
		593	feature_ro_compat dd ? ; +100
		594	uuid rb 16 ; +104
		595	volume_name rb 16 ; +120
		596	last_mounted rb 64 ; +136
		597	algo_bitmap dd ? ; +200
		598	prealloc_blocks db ? ; +204
		599	preallock_dir_blocks db ? ; +205
		600	reserved_gdt_blocks dw ? ; +206
		601	journal_uuid rb 16 ; +208
		602	journal_inum dd ? ; +224
		603	journal_dev dd ? ; +228
		604	last_orphan dd ? ; +232
		605	hash_seed rd 4 ; +236
		606	def_hash_version db ? ; +252
		607	reserved rb 3 ; +253 (reserved)
		608	default_mount_options dd ? ; +256
		609	first_meta_bg dd ? ; +260
		610	mkfs_time dd ? ; +264
		611	jnl_blocks rd 17 ; +268
		612	blocks_count_hi dd ? ; +336
		613	r_blocks_count_hi dd ? ; +340
		614	free_blocks_count_hi dd ? ; +344
		615	min_extra_isize dw ? ; +348
		616	want_extra_isize dw ? ; +350
		617	flags dd ? ; +352
		618	raid_stride dw ? ; +356
		619	mmp_interval dw ? ; +358
		620	mmp_block dq ? ; +360
		621	raid_stripe_width dd ? ; +368
		622	log_groups_per_flex db ? ; +372
		623	ends
		624
		625	; Header block extents.
		626	struct EXT4_EXTENT_HEADER
		627	eh_magic dw ? ; Magic value of 0xF30A, for ext4.
		628	eh_entries dw ? ; Number of blocks covered by the extent.
		629	eh_max dw ? ; Capacity of entries.
		630	eh_depth dw ? ; Tree depth (if 0, extents in the array are not extent indexes)
		631	eh_generation dd ? ; ???
		632	ends
		633
		634	; Extent.
		635	struct EXT4_EXTENT
		636	ee_block dd ? ; First logical block extent covers.
		637	ee_len dw ? ; Number of blocks covered by extent.
		638	ee_start_hi dw ? ; Upper 16 bits of 48-bit address (unused in KOS)
		639	ee_start_lo dd ? ; Lower 32 bits of 48-bit address.
		640	ends
		641
		642	; Index on-disk structure; pointer to block of extents/indexes.
		643	struct EXT4_EXTENT_IDX
		644	ei_block dd ? ; Covers logical blocks from here.
		645	ei_leaf_lo dd ? ; Lower 32-bits of pointer to the physical block of the next level.
		646	ei_leaf_hi dw ? ; Higher 16-bits (unused in KOS).
		647	ei_unused dw ? ; Reserved.
		648	ends

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(root)/kernel/trunk/fs/ext2/ext2.inc @ 4067 – Rev 3935