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
4066	shikhin	10	; Future jobs for driver, in order of preference:
		11	; * clean up existing extents support.
		12	; * add b-tree directories support.
		13	; * add long file support.
		14	; * add journal support.
		15	; * add minor features that come with ext3/4.
		16
3935	shikhin	17	; Recommended move to some kernel-wide bitmap handling code (with a bit of abstraction, of course).
		18
		19	;---------------------------------------------------------------------
		20	; Clears a bit.
		21	; Input: eax = index into bitmap.
		22	; [EXTFS.ext2_save_block] = address of bitmap.
		23	; ebp = address of EXTFS.
		24	; Output: Bit cleared.
		25	; eax = non-zero, if already cleared.
		26	;---------------------------------------------------------------------
		27	bitmap_clear_bit:
		28	push ebx ecx edx
		29
		30	xor edx, edx
		31	mov ecx, 8
		32	div ecx
		33
		34	add eax, [ebp + EXTFS.ext2_save_block]
		35
		36	; Get the mask.
		37	mov ebx, 1
		38	mov ecx, edx
		39	shl ebx, cl
		40
		41	test [eax], ebx
		42	jz .cleared
		43
		44	not ebx
		45	and [eax], ebx
		46
		47	xor eax, eax
		48	.return:
		49	pop edx ecx ebx
		50	ret
		51
		52	; Already cleared.
		53	.cleared:
		54	xor eax, eax
		55	not eax
		56	jmp .return
		57
		58	;---------------------------------------------------------------------
		59	; Finds free bit in the bitmap.
		60	; Input: ecx = number of bits in the bitmap.
		61	; [EXTFS.ext2_save_block] = address of bitmap.
		62	; ebp = address of EXTFS.
		63	; Output: eax = index of free bit in the bitmap; marked set.
		64	; 0xFFFFFFFF if no free bit found.
		65	;---------------------------------------------------------------------
		66	ext2_find_free_bit:
		67	bitmap_find_free_bit:
		68	push esi ebx ecx edx
		69	mov esi, [ebp + EXTFS.ext2_save_block]
		70
		71	; Get total DWORDS in eax; total bits in last dword, if any, in edx.
		72	xor edx, edx
		73	mov eax, ecx
		74	mov ecx, 32
		75	div ecx
		76
		77	mov ecx, eax
		78	xor eax, eax
		79	push edx
		80
		81	test ecx, ecx
		82	jz .last_bits
		83
		84	; Check in the DWORDS.
		85	.dwords:
		86	mov ebx, [esi]
		87	not ebx
		88
		89	bsf edx, ebx
		90
		91	; If 0, then the original value would be 0xFFFFFFFF, hence no free bits.
		92	jz @F
		93
		94	; We found the value. Let's return with it.
		95	add esp, 4
4066	shikhin	96
3935	shikhin	97	add eax, edx
		98	jmp .return
		99
		100	@@:
		101	add esi, 4
		102	add eax, 32
		103	loop .dwords
		104
		105	.last_bits:
		106	; Check in the last few bits.
		107	pop ecx
		108	test ecx, ecx
		109	jz @F
		110
		111	mov ebx, [esi]
		112	not ebx
		113	bsf ebx, edx
		114
		115	; If 0, no free bits.
		116	jz @F
		117
		118	; If free bit is greater than the last known bit, then error.
		119	cmp edx, ecx
		120	jg @F
		121
		122	add eax, edx
		123	jmp .return
		124
		125	@@:
		126	; Didn't find any free bits.
		127	xor eax, eax
		128	not eax
		129	jmp @F
		130
		131	.return:
		132	mov ecx, edx
		133	mov edx, 1
		134	shl edx, cl
		135	or [esi], edx
		136
		137	@@:
		138	pop edx ecx ebx esi
		139	ret
		140
		141	; Recommended move to some kernel-wide string handling code.
		142	;---------------------------------------------------------------------
		143	; Find the length of a string.
		144	; Input: esi = source.
		145	; Output: length in ecx
		146	;---------------------------------------------------------------------
		147	strlen:
		148	push eax esi
		149	xor ecx, ecx
		150
		151	@@:
		152	lodsb
		153	test al, al
		154	jz .ret
		155
		156	inc ecx
		157	jmp @B
		158
		159	.ret:
		160	pop esi eax
		161	ret
		162
		163	;---------------------------------------------------------------------
		164	; Convert UTF-8 string to ASCII-string (codepage 866)
		165	; Input: esi = source.
		166	; edi = buffer.
		167	; ecx = length of source.
		168	; Output: destroys eax, esi, edi
		169	;---------------------------------------------------------------------
		170	utf8_to_cp866:
		171	; Check for zero-length string.
		172	jecxz .return
		173
		174	.start:
		175	lodsw
		176	cmp al, 0x80
		177	jb .ascii
		178
		179	xchg al, ah ; Big-endian.
		180	cmp ax, 0xd080
		181	jz .yo1
		182
		183	cmp ax, 0xd191
		184	jz .yo2
		185
		186	cmp ax, 0xd090
		187	jb .unk
		188
		189	cmp ax, 0xd180
		190	jb .rus1
		191
		192	cmp ax, 0xd190
		193	jb .rus2
		194
		195	.unk:
		196	mov al, '_'
		197	jmp .doit
		198
		199	.yo1:
		200	mov al, 0xf0 ; Ё capital.
		201	jmp .doit
		202
		203	.yo2:
		204	mov al, 0xf1 ; ё small.
		205	jmp .doit
		206
		207	.rus1:
		208	sub ax, 0xd090 - 0x80
		209	jmp .doit
		210
		211	.rus2:
		212	sub ax, 0xd18f - 0xEF
		213
		214	.doit:
		215	stosb
		216	sub ecx, 2
		217	ja .start
		218	ret
		219
		220	.ascii:
		221	stosb
		222	dec esi
		223	dec ecx
		224	jnz .start
		225
		226	.return:
		227	ret
		228
		229	; Recommended move to some kernel-wide time handling code.
		230
		231	; Total cumulative seconds till each month.
		232	cumulative_seconds_in_month:
		233	.january: dd 0 * (60 * 60 * 24)
		234	.february: dd 31 * (60 * 60 * 24)
		235	.march: dd 59 * (60 * 60 * 24)
		236	.april: dd 90 * (60 * 60 * 24)
		237	.may: dd 120 * (60 * 60 * 24)
		238	.june: dd 151 * (60 * 60 * 24)
		239	.july: dd 181 * (60 * 60 * 24)
		240	.august: dd 212 * (60 * 60 * 24)
		241	.september: dd 243 * (60 * 60 * 24)
		242	.october: dd 273 * (60 * 60 * 24)
		243	.november: dd 304 * (60 * 60 * 24)
		244	.december: dd 334 * (60 * 60 * 24)
		245
		246	current_bdfe_time:
		247	dd 0
		248	current_bdfe_date:
		249	dd 0
		250
		251	;---------------------------------------------------------------------
		252	; Stores current unix time.
		253	; Input: edi = buffer to output Unix time.
		254	;---------------------------------------------------------------------
		255	current_unix_time:
		256	push eax esi
		257	mov esi, current_bdfe_time
		258
		259	; Just a small observation:
		260	; The CMOS is a pretty bad source to get time from. One shouldn't rely on it,
		261	; since it messes up the time by tiny bits. Of course, this is all technical,
		262	; but one can look it up on the osdev wiki. What is better is to get the time
		263	; from CMOS during boot, then update system time using a more accurate timer.
		264	; I'll probably add that after the Summer of Code, so TODO! TODO! TODO!.
		265
		266	; Get time from CMOS.
		267	; Seconds.
		268	mov al, 0x00
		269	out 0x70, al
		270	in al, 0x71
		271	call bcd2bin
		272	mov [esi + 0], al
		273
		274	; Minute.
		275	mov al, 0x02
		276	out 0x70, al
		277	in al, 0x71
		278	call bcd2bin
		279	mov [esi + 1], al
		280
		281	; Hour.
		282	mov al, 0x04
		283	out 0x70, al
		284	in al, 0x71
		285	call bcd2bin
		286	mov [esi + 2], al
		287
		288	; Get date.
		289
		290	; Day.
		291	mov al, 0x7
		292	out 0x70, al
		293	in al, 0x71
		294	call bcd2bin
		295	mov [esi + 4], al
		296
		297	; Month.
		298	mov al, 0x8
		299	out 0x70, al
		300	in al, 0x71
		301	call bcd2bin
		302	mov [esi + 5], al
		303
		304	; Year.
		305	mov al, 0x9
		306	out 0x70, al
		307	in al, 0x71
		308	call bcd2bin
		309	add ax, 2000 ; CMOS only returns last two digits.
		310	; Note that everywhere in KolibriOS this is used.
		311	; This is hacky, since the RTC can be incorrectly set
		312	; to something before 2000.
		313	mov [esi + 6], ax
		314
		315	call bdfe_to_unix_time
		316	pop esi eax
		317	ret
		318
		319	;---------------------------------------------------------------------
		320	; Convert time+date from BDFE to Unix time.
		321	; Input: esi = pointer to BDFE time+date.
		322	; edi = buffer to output Unix time.
		323	;---------------------------------------------------------------------
		324	bdfe_to_unix_time:
		325	push eax ebx ecx edx
		326	mov dword[edi], 0x00000000
		327
		328	; The minimum representable time is 1901-12-13.
		329	cmp word[esi + 6], 1901
		330	jb .ret
		331	jg .max
		332
		333	cmp byte[esi + 5], 12
		334	jb .ret
		335
		336	cmp byte[esi + 4], 13
		337	jbe .ret
		338	jg .convert
		339
		340	; Check if it is more than the maximum representable time.
		341	.max:
		342	; The maximum representable time is 2038-01-19.
		343	cmp word[esi + 6], 2038
		344	jg .ret
		345	jb .convert
		346
		347	cmp byte[esi + 5], 1
		348	jg .ret
		349
		350	cmp byte[esi + 4], 19
		351	jge .ret
		352
		353	; Convert the time.
		354	.convert:
		355	; Get if current year is leap year in ECX.
		356	xor ecx, ecx
		357	mov ebx, 4
		358	xor edx, edx
		359
		360	cmp word[esi + 6], 1970
		361	jb .negative
		362
		363	movzx eax, word[esi + 6] ; Year.
		364	cmp byte[esi + 5], 3 ; If the month is less than March, than that year doesn't matter.
		365	jge @F
		366
		367	test eax, 3
		368	; Not a leap year.
		369	jnz @F
		370
		371	inc ecx
		372	@@:
		373	; Number of leap years between two years = ((end date - 1)/4) - (1970/4)
		374	dec eax
		375	div ebx
		376	sub eax, 1970/4
		377
		378	; EAX is the number of leap years.
		379	add eax, ecx
		380	mov ecx, (60 * 60 * 24) ; Seconds in a day.
		381	mul ecx
		382
		383	; Account for leap years, i.e., one day extra for each.
		384	add [edi], eax
		385
		386	; Get total days in EAX.
		387	movzx eax, byte[esi + 4]
		388	dec eax
		389	mul ecx
		390
		391	; Account for days.
		392	add [edi], eax
		393
		394	; Account for month.
		395	movzx eax, byte[esi + 5]
		396	dec eax
		397	mov eax, [cumulative_seconds_in_month + (eax * 4)]
		398	add [edi], eax
		399
		400	; Account for year.
		401	movzx eax, word[esi + 6]
		402	sub eax, 1970
		403	mov ecx, (60 * 60 * 24) * 365 ; Seconds in a year.
		404	mul ecx
		405	add [edi], eax
		406
		407	; Seconds.
		408	movzx eax, byte[esi + 0]
		409	add [edi], eax
		410
		411	; Minutes.
		412	movzx eax, byte[esi + 1]
		413	mov ecx, 60
		414	mul ecx
		415	add [edi], eax
		416
		417	; Hours.
		418	movzx eax, byte[esi + 2]
		419	mov ecx, (60 * 60)
		420	mul ecx
		421	add [edi], eax
		422
		423	; The time wanted is before the epoch; handle it here.
		424	.negative:
		425	; TODO.
		426
		427	.ret:
		428	pop edx ecx ebx eax
		429	ret
		430
		431	; Recommended move to some kernel-wide alloc handling code.
		432	macro KERNEL_ALLOC store, label
		433	{
		434	call kernel_alloc
		435	mov store, eax
		436	test eax, eax
		437	jz label
		438	}
		439
		440	macro KERNEL_FREE data, label
		441	{
		442	cmp data, 0
		443	jz label
		444	push data
		445	call kernel_free
		446	}
		447
		448	struct EXTFS PARTITION
		449	lock MUTEX
		450	partition_flags dd ?
		451	log_block_size dd ?
		452	block_size dd ?
		453	count_block_in_block dd ?
		454	blocks_per_group dd ?
		455	global_desc_table dd ?
		456	root_inode dd ? ; Pointer to root inode in memory.
		457	inode_size dd ?
		458	count_pointer_in_block dd ? ; (block_size / 4)
		459	count_pointer_in_block_square dd ? ; (block_size / 4)**2
		460	ext2_save_block dd ? ; Block for 1 global procedure.
		461	ext2_temp_block dd ? ; Block for small procedures.
		462	ext2_save_inode dd ? ; inode for global procedures.
		463	ext2_temp_inode dd ? ; inode for small procedures.
		464	groups_count dd ?
		465	superblock rd 1024/4
		466	ends
		467
		468	; EXT2 revisions.
		469	EXT2_GOOD_OLD_REV = 0
		470
		471	; For fs_type.
		472	FS_TYPE_UNDEFINED = 0
		473	FS_TYPE_EXT = 2
		474
		475	; Some set inodes.
		476	EXT2_BAD_INO = 1
		477	EXT2_ROOT_INO = 2
		478	EXT2_ACL_IDX_INO = 3
		479	EXT2_ACL_DATA_INO = 4
		480	EXT2_BOOT_LOADER_INO = 5
		481	EXT2_UNDEL_DIR_INO = 6
		482
		483	; EXT2_SUPER_MAGIC.
		484	EXT2_SUPER_MAGIC = 0xEF53
		485	EXT2_VALID_FS = 1
		486
		487	; Flags defining i_mode values.
		488	EXT2_S_IFMT = 0xF000 ; Mask for file type.
		489
		490	EXT2_S_IFREG = 0x8000 ; Regular file.
		491	EXT2_S_IFDIR = 0x4000 ; Directory.
		492
		493	; File type defining values in directory entry.
		494	EXT2_FT_REG_FILE = 1 ; Regular file.
		495	EXT2_FT_DIR = 2 ; Directory.
		496
		497	; Flags used by KolibriOS.
		498	FS_FT_HIDDEN = 2
		499	FS_FT_DIR = 0x10 ; Directory.
		500
		501	; ext2 partition flags.
		502	EXT2_RO = 0x01
		503
		504	FS_FT_ASCII = 0 ; Name in ASCII.
		505	FS_FT_UNICODE = 1 ; Name in Unicode.
		506
		507	EXT2_FEATURE_INCOMPAT_FILETYPE = 0x0002 ; Have file type in directory entry.
		508	EXT4_FEATURE_INCOMPAT_EXTENTS = 0x0040 ; Extents.
		509	EXT4_FEATURE_INCOMPAT_FLEX_BG = 0x0200 ; Flexible block groups.
		510
		511	EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER = 0x0001 ; Sparse Superblock
		512	EXT2_FEATURE_RO_COMPAT_LARGE_FILE = 0x0002 ; Large file support (64-bit file size)
		513
		514	; Implemented ext[2,3,4] features.
		515	EXT4_FEATURE_INCOMPAT_SUPP = EXT2_FEATURE_INCOMPAT_FILETYPE \
		516	or EXT4_FEATURE_INCOMPAT_EXTENTS \
		517	or EXT4_FEATURE_INCOMPAT_FLEX_BG
		518
		519	; Implemented features which otherwise require "read-only" mount.
		520	EXT2_FEATURE_RO_COMPAT_SUPP = EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER \
		521	or EXT2_FEATURE_RO_COMPAT_LARGE_FILE
		522
		523	; ext4 features not support for write.
		524	EXT4_FEATURE_INCOMPAT_W_NOT_SUPP = EXT4_FEATURE_INCOMPAT_EXTENTS \
		525	or EXT4_FEATURE_INCOMPAT_FLEX_BG
		526
		527	; Flags specified in i_flags.
		528	EXT2_EXTENTS_FL = 0x00080000 ; Extents.
		529
		530	struct EXT2_INODE_STRUC
		531	i_mode dw ?
		532	i_uid dw ?
		533	i_size dd ?
		534	i_atime dd ?
		535	i_ctime dd ?
		536	i_mtime dd ?
		537	i_dtime dd ?
		538	i_gid dw ?
		539	i_links_count dw ?
		540	i_blocks dd ?
		541	i_flags dd ?
		542	i_osd1 dd ?
		543	i_block rd 15
		544	i_generation dd ?
		545	i_file_acl dd ?
		546	i_dir_acl dd ?
		547	i_faddr dd ?
		548	i_osd2 dd ? ; 12 bytes.
		549	ends
		550
		551	struct EXT2_DIR_STRUC
		552	inode dd ?
		553	rec_len dw ?
		554	name_len db ?
		555	file_type db ?
		556	name db ? ; 255 (max) bytes.
		557	ends
		558
		559	struct EXT2_BLOCK_GROUP_DESC
		560	block_bitmap dd ? ; +0
		561	inode_bitmap dd ? ; +4
		562	inode_table dd ? ; +8
		563	free_blocks_count dw ? ; +12
		564	free_inodes_count dw ? ; +14
		565	used_dirs_count dw ? ; +16
		566	pad dw ? ; +18
		567	reserved rb 12 ; +20
		568	ends
		569
		570	struct EXT2_SB_STRUC
		571	inodes_count dd ? ; +0
		572	blocks_count dd ? ; +4
		573	r_block_count dd ? ; +8
		574	free_block_count dd ? ; +12
		575	free_inodes_count dd ? ; +16
		576	first_data_block dd ? ; +20
		577	log_block_size dd ? ; +24
		578	log_frag_size dd ? ; +28
		579	blocks_per_group dd ? ; +32
		580	frags_per_group dd ? ; +36
		581	inodes_per_group dd ? ; +40
		582	mtime dd ? ; +44
		583	wtime dd ? ; +48
		584	mnt_count dw ? ; +52
		585	max_mnt_count dw ? ; +54
		586	magic dw ? ; +56
		587	state dw ? ; +58
		588	errors dw ? ; +60
		589	minor_rev_level dw ? ; +62
		590	lastcheck dd ? ; +64
		591	check_intervals dd ? ; +68
		592	creator_os dd ? ; +72
		593	rev_level dd ? ; +76
		594	def_resuid dw ? ; +80
		595	def_resgid dw ? ; +82
		596	first_ino dd ? ; +84
		597	inode_size dw ? ; +88
		598	block_group_nr dw ? ; +90
		599	feature_compat dd ? ; +92
		600	feature_incompat dd ? ; +96
		601	feature_ro_compat dd ? ; +100
		602	uuid rb 16 ; +104
		603	volume_name rb 16 ; +120
		604	last_mounted rb 64 ; +136
		605	algo_bitmap dd ? ; +200
		606	prealloc_blocks db ? ; +204
		607	preallock_dir_blocks db ? ; +205
		608	reserved_gdt_blocks dw ? ; +206
		609	journal_uuid rb 16 ; +208
		610	journal_inum dd ? ; +224
		611	journal_dev dd ? ; +228
		612	last_orphan dd ? ; +232
		613	hash_seed rd 4 ; +236
		614	def_hash_version db ? ; +252
		615	reserved rb 3 ; +253 (reserved)
		616	default_mount_options dd ? ; +256
		617	first_meta_bg dd ? ; +260
		618	mkfs_time dd ? ; +264
		619	jnl_blocks rd 17 ; +268
		620	blocks_count_hi dd ? ; +336
		621	r_blocks_count_hi dd ? ; +340
		622	free_blocks_count_hi dd ? ; +344
		623	min_extra_isize dw ? ; +348
		624	want_extra_isize dw ? ; +350
		625	flags dd ? ; +352
		626	raid_stride dw ? ; +356
		627	mmp_interval dw ? ; +358
		628	mmp_block dq ? ; +360
		629	raid_stripe_width dd ? ; +368
		630	log_groups_per_flex db ? ; +372
		631	ends
		632
		633	; Header block extents.
		634	struct EXT4_EXTENT_HEADER
		635	eh_magic dw ? ; Magic value of 0xF30A, for ext4.
		636	eh_entries dw ? ; Number of blocks covered by the extent.
		637	eh_max dw ? ; Capacity of entries.
		638	eh_depth dw ? ; Tree depth (if 0, extents in the array are not extent indexes)
		639	eh_generation dd ? ; ???
		640	ends
		641
		642	; Extent.
		643	struct EXT4_EXTENT
		644	ee_block dd ? ; First logical block extent covers.
		645	ee_len dw ? ; Number of blocks covered by extent.
		646	ee_start_hi dw ? ; Upper 16 bits of 48-bit address (unused in KOS)
		647	ee_start_lo dd ? ; Lower 32 bits of 48-bit address.
		648	ends
		649
		650	; Index on-disk structure; pointer to block of extents/indexes.
		651	struct EXT4_EXTENT_IDX
		652	ei_block dd ? ; Covers logical blocks from here.
		653	ei_leaf_lo dd ? ; Lower 32-bits of pointer to the physical block of the next level.
		654	ei_leaf_hi dw ? ; Higher 16-bits (unused in KOS).
		655	ei_unused dw ? ; Reserved.
		656	ends

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(root)/kernel/trunk/fs/ext2/ext2.inc @ 4067 – Rev 4066