WebSVN – Kolibri OS – Blame – /kernel/branches/kolibri-process/fs/ext2/ext2.inc

Rev	Author	Line No.	Line
4429	Serge	1	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		2	;; ;;
		3	;; Contains ext2 structures, and macros. ;;
		4	;; ;;
4923	Serge	5	;; Copyright (C) KolibriOS team 2013-2014. All rights reserved. ;;
		6	;; Distributed under terms of the GNU General Public License ;;
4429	Serge	7	;; ;;
		8	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		9
4923	Serge	10	$Revision: 4891 $
		11
		12
4429	Serge	13	; Future jobs for driver, in order of preference:
		14	; * clean up existing extents support.
		15	; * add b-tree directories support.
		16	; * add long file support.
		17	; * add journal support.
		18	; * add minor features that come with ext3/4.
		19
		20	; Recommended move to some kernel-wide bitmap handling code (with a bit of abstraction, of course).
		21
		22	;---------------------------------------------------------------------
		23	; Clears a bit.
		24	; Input: eax = index into bitmap.
		25	; [EXTFS.ext2_save_block] = address of bitmap.
		26	; ebp = address of EXTFS.
		27	; Output: Bit cleared.
		28	; eax = non-zero, if already cleared.
		29	;---------------------------------------------------------------------
		30	bitmap_clear_bit:
		31	push ebx ecx edx
		32
		33	xor edx, edx
		34	mov ecx, 8
		35	div ecx
		36
		37	add eax, [ebp + EXTFS.ext2_save_block]
		38
		39	; Get the mask.
		40	mov ebx, 1
		41	mov ecx, edx
		42	shl ebx, cl
		43
		44	test [eax], ebx
		45	jz .cleared
		46
		47	not ebx
		48	and [eax], ebx
		49
		50	xor eax, eax
		51	.return:
		52	pop edx ecx ebx
		53	ret
		54
		55	; Already cleared.
		56	.cleared:
		57	xor eax, eax
		58	not eax
		59	jmp .return
		60
		61	;---------------------------------------------------------------------
		62	; Finds free bit in the bitmap.
		63	; Input: ecx = number of bits in the bitmap.
		64	; [EXTFS.ext2_save_block] = address of bitmap.
		65	; ebp = address of EXTFS.
		66	; Output: eax = index of free bit in the bitmap; marked set.
		67	; 0xFFFFFFFF if no free bit found.
		68	;---------------------------------------------------------------------
		69	ext2_find_free_bit:
		70	bitmap_find_free_bit:
		71	push esi ebx ecx edx
		72	mov esi, [ebp + EXTFS.ext2_save_block]
		73
		74	; Get total DWORDS in eax; total bits in last dword, if any, in edx.
		75	xor edx, edx
		76	mov eax, ecx
		77	mov ecx, 32
		78	div ecx
		79
		80	mov ecx, eax
		81	xor eax, eax
		82	push edx
		83
		84	test ecx, ecx
		85	jz .last_bits
		86
		87	; Check in the DWORDS.
		88	.dwords:
		89	mov ebx, [esi]
		90	not ebx
		91
		92	bsf edx, ebx
		93
		94	; If 0, then the original value would be 0xFFFFFFFF, hence no free bits.
		95	jz @F
		96
		97	; We found the value. Let's return with it.
		98	add esp, 4
		99
		100	add eax, edx
		101	jmp .return
		102
		103	@@:
		104	add esi, 4
		105	add eax, 32
		106	loop .dwords
		107
		108	.last_bits:
		109	; Check in the last few bits.
		110	pop ecx
		111	test ecx, ecx
		112	jz @F
		113
		114	mov ebx, [esi]
		115	not ebx
		116	bsf ebx, edx
		117
		118	; If 0, no free bits.
		119	jz @F
		120
		121	; If free bit is greater than the last known bit, then error.
		122	cmp edx, ecx
		123	jg @F
		124
		125	add eax, edx
		126	jmp .return
		127
		128	@@:
		129	; Didn't find any free bits.
		130	xor eax, eax
		131	not eax
		132	jmp @F
		133
		134	.return:
		135	mov ecx, edx
		136	mov edx, 1
		137	shl edx, cl
		138	or [esi], edx
		139
		140	@@:
		141	pop edx ecx ebx esi
		142	ret
		143
		144	; Recommended move to some kernel-wide string handling code.
		145	;---------------------------------------------------------------------
		146	; Find the length of a string.
		147	; Input: esi = source.
		148	; Output: length in ecx
		149	;---------------------------------------------------------------------
		150	strlen:
		151	push eax esi
		152	xor ecx, ecx
		153
		154	@@:
		155	lodsb
		156	test al, al
		157	jz .ret
		158
		159	inc ecx
		160	jmp @B
		161
		162	.ret:
		163	pop esi eax
		164	ret
		165
		166	;---------------------------------------------------------------------
		167	; Convert UTF-8 string to ASCII-string (codepage 866)
		168	; Input: esi = source.
		169	; edi = buffer.
		170	; ecx = length of source.
		171	; Output: destroys eax, esi, edi
		172	;---------------------------------------------------------------------
		173	utf8_to_cp866:
		174	; Check for zero-length string.
		175	jecxz .return
		176
		177	.start:
		178	lodsw
		179	cmp al, 0x80
		180	jb .ascii
		181
		182	xchg al, ah ; Big-endian.
		183	cmp ax, 0xd080
		184	jz .yo1
		185
		186	cmp ax, 0xd191
		187	jz .yo2
		188
		189	cmp ax, 0xd090
		190	jb .unk
		191
		192	cmp ax, 0xd180
		193	jb .rus1
		194
		195	cmp ax, 0xd190
		196	jb .rus2
		197
		198	.unk:
		199	mov al, '_'
		200	jmp .doit
		201
		202	.yo1:
		203	mov al, 0xf0 ; Ё capital.
		204	jmp .doit
		205
		206	.yo2:
		207	mov al, 0xf1 ; ё small.
		208	jmp .doit
		209
		210	.rus1:
		211	sub ax, 0xd090 - 0x80
		212	jmp .doit
		213
		214	.rus2:
		215	sub ax, 0xd18f - 0xEF
		216
		217	.doit:
		218	stosb
		219	sub ecx, 2
		220	ja .start
		221	ret
		222
		223	.ascii:
		224	stosb
		225	dec esi
		226	dec ecx
		227	jnz .start
		228
		229	.return:
		230	ret
		231
		232	; Recommended move to some kernel-wide time handling code.
		233
		234	; Total cumulative seconds till each month.
		235	cumulative_seconds_in_month:
		236	.january: dd 0 * (60 * 60 * 24)
		237	.february: dd 31 * (60 * 60 * 24)
		238	.march: dd 59 * (60 * 60 * 24)
		239	.april: dd 90 * (60 * 60 * 24)
		240	.may: dd 120 * (60 * 60 * 24)
		241	.june: dd 151 * (60 * 60 * 24)
		242	.july: dd 181 * (60 * 60 * 24)
		243	.august: dd 212 * (60 * 60 * 24)
		244	.september: dd 243 * (60 * 60 * 24)
		245	.october: dd 273 * (60 * 60 * 24)
		246	.november: dd 304 * (60 * 60 * 24)
		247	.december: dd 334 * (60 * 60 * 24)
		248
		249	current_bdfe_time:
		250	dd 0
		251	current_bdfe_date:
		252	dd 0
		253
		254	;---------------------------------------------------------------------
		255	; Stores current unix time.
		256	; Input: edi = buffer to output Unix time.
		257	;---------------------------------------------------------------------
		258	current_unix_time:
		259	push eax esi
		260	mov esi, current_bdfe_time
		261
		262	; Just a small observation:
		263	; The CMOS is a pretty bad source to get time from. One shouldn't rely on it,
		264	; since it messes up the time by tiny bits. Of course, this is all technical,
		265	; but one can look it up on the osdev wiki. What is better is to get the time
		266	; from CMOS during boot, then update system time using a more accurate timer.
		267	; I'll probably add that after the Summer of Code, so TODO! TODO! TODO!.
		268
		269	; Get time from CMOS.
		270	; Seconds.
		271	mov al, 0x00
		272	out 0x70, al
		273	in al, 0x71
		274	call bcd2bin
		275	mov [esi + 0], al
		276
		277	; Minute.
		278	mov al, 0x02
		279	out 0x70, al
		280	in al, 0x71
		281	call bcd2bin
		282	mov [esi + 1], al
		283
		284	; Hour.
		285	mov al, 0x04
		286	out 0x70, al
		287	in al, 0x71
		288	call bcd2bin
		289	mov [esi + 2], al
		290
		291	; Get date.
		292
		293	; Day.
		294	mov al, 0x7
		295	out 0x70, al
		296	in al, 0x71
		297	call bcd2bin
		298	mov [esi + 4], al
		299
		300	; Month.
		301	mov al, 0x8
		302	out 0x70, al
		303	in al, 0x71
		304	call bcd2bin
		305	mov [esi + 5], al
		306
		307	; Year.
		308	mov al, 0x9
		309	out 0x70, al
		310	in al, 0x71
		311	call bcd2bin
		312	add ax, 2000 ; CMOS only returns last two digits.
		313	; Note that everywhere in KolibriOS this is used.
		314	; This is hacky, since the RTC can be incorrectly set
		315	; to something before 2000.
		316	mov [esi + 6], ax
		317
		318	call bdfe_to_unix_time
		319	pop esi eax
		320	ret
		321
		322	;---------------------------------------------------------------------
		323	; Convert time+date from BDFE to Unix time.
		324	; Input: esi = pointer to BDFE time+date.
		325	; edi = buffer to output Unix time.
		326	;---------------------------------------------------------------------
		327	bdfe_to_unix_time:
		328	push eax ebx ecx edx
		329	mov dword[edi], 0x00000000
		330
		331	; The minimum representable time is 1901-12-13.
		332	cmp word[esi + 6], 1901
		333	jb .ret
		334	jg .max
		335
		336	cmp byte[esi + 5], 12
		337	jb .ret
		338
		339	cmp byte[esi + 4], 13
		340	jbe .ret
		341	jg .convert
		342
		343	; Check if it is more than the maximum representable time.
		344	.max:
		345	; The maximum representable time is 2038-01-19.
		346	cmp word[esi + 6], 2038
		347	jg .ret
		348	jb .convert
		349
		350	cmp byte[esi + 5], 1
		351	jg .ret
		352
		353	cmp byte[esi + 4], 19
		354	jge .ret
		355
		356	; Convert the time.
		357	.convert:
		358	; Get if current year is leap year in ECX.
		359	xor ecx, ecx
		360	mov ebx, 4
		361	xor edx, edx
		362
		363	cmp word[esi + 6], 1970
		364	jb .negative
		365
		366	movzx eax, word[esi + 6] ; Year.
		367	cmp byte[esi + 5], 3 ; If the month is less than March, than that year doesn't matter.
		368	jge @F
		369
		370	test eax, 3
		371	; Not a leap year.
		372	jnz @F
		373
		374	inc ecx
		375	@@:
		376	; Number of leap years between two years = ((end date - 1)/4) - (1970/4)
		377	dec eax
		378	div ebx
		379	sub eax, 1970/4
		380
		381	; EAX is the number of leap years.
		382	add eax, ecx
		383	mov ecx, (60 * 60 * 24) ; Seconds in a day.
		384	mul ecx
		385
		386	; Account for leap years, i.e., one day extra for each.
		387	add [edi], eax
		388
		389	; Get total days in EAX.
		390	movzx eax, byte[esi + 4]
		391	dec eax
		392	mul ecx
		393
		394	; Account for days.
		395	add [edi], eax
		396
		397	; Account for month.
		398	movzx eax, byte[esi + 5]
		399	dec eax
		400	mov eax, [cumulative_seconds_in_month + (eax * 4)]
		401	add [edi], eax
		402
		403	; Account for year.
		404	movzx eax, word[esi + 6]
		405	sub eax, 1970
		406	mov ecx, (60 * 60 * 24) * 365 ; Seconds in a year.
		407	mul ecx
		408	add [edi], eax
		409
		410	; Seconds.
		411	movzx eax, byte[esi + 0]
		412	add [edi], eax
		413
		414	; Minutes.
		415	movzx eax, byte[esi + 1]
		416	mov ecx, 60
		417	mul ecx
		418	add [edi], eax
		419
		420	; Hours.
		421	movzx eax, byte[esi + 2]
		422	mov ecx, (60 * 60)
		423	mul ecx
		424	add [edi], eax
		425
		426	; The time wanted is before the epoch; handle it here.
		427	.negative:
		428	; TODO.
		429
		430	.ret:
		431	pop edx ecx ebx eax
		432	ret
		433
		434	; Recommended move to some kernel-wide alloc handling code.
		435	macro KERNEL_ALLOC store, label
		436	{
		437	call kernel_alloc
		438	mov store, eax
		439	test eax, eax
		440	jz label
		441	}
		442
		443	macro KERNEL_FREE data, label
		444	{
		445	cmp data, 0
		446	jz label
		447	push data
		448	call kernel_free
		449	}
		450
		451	struct EXTFS PARTITION
		452	lock MUTEX
		453	partition_flags dd ?
		454	log_block_size dd ?
		455	block_size dd ?
		456	count_block_in_block dd ?
		457	blocks_per_group dd ?
		458	global_desc_table dd ?
		459	root_inode dd ? ; Pointer to root inode in memory.
		460	inode_size dd ?
		461	count_pointer_in_block dd ? ; (block_size / 4)
		462	count_pointer_in_block_square dd ? ; (block_size / 4)**2
		463	ext2_save_block dd ? ; Block for 1 global procedure.
		464	ext2_temp_block dd ? ; Block for small procedures.
		465	ext2_save_inode dd ? ; inode for global procedures.
		466	ext2_temp_inode dd ? ; inode for small procedures.
		467	groups_count dd ?
		468	superblock rd 1024/4
		469	ends
		470
		471	; EXT2 revisions.
		472	EXT2_GOOD_OLD_REV = 0
		473
		474	; For fs_type.
		475	FS_TYPE_UNDEFINED = 0
		476	FS_TYPE_EXT = 2
		477
		478	; Some set inodes.
		479	EXT2_BAD_INO = 1
		480	EXT2_ROOT_INO = 2
		481	EXT2_ACL_IDX_INO = 3
		482	EXT2_ACL_DATA_INO = 4
		483	EXT2_BOOT_LOADER_INO = 5
		484	EXT2_UNDEL_DIR_INO = 6
		485
		486	; EXT2_SUPER_MAGIC.
		487	EXT2_SUPER_MAGIC = 0xEF53
		488	EXT2_VALID_FS = 1
		489
		490	; Flags defining i_mode values.
		491	EXT2_S_IFMT = 0xF000 ; Mask for file type.
		492
		493	EXT2_S_IFREG = 0x8000 ; Regular file.
		494	EXT2_S_IFDIR = 0x4000 ; Directory.
		495
		496	EXT2_S_IRUSR = 0x0100 ; User read
		497	EXT2_S_IWUSR = 0x0080 ; User write
		498	EXT2_S_IXUSR = 0x0040 ; User execute
		499	EXT2_S_IRGRP = 0x0020 ; Group read
		500	EXT2_S_IWGRP = 0x0010 ; Group write
		501	EXT2_S_IXGRP = 0x0008 ; Group execute
		502	EXT2_S_IROTH = 0x0004 ; Others read
		503	EXT2_S_IWOTH = 0x0002 ; Others write
		504	EXT2_S_IXOTH = 0x0001 ; Others execute
		505
		506	PERMISSIONS = EXT2_S_IRUSR or EXT2_S_IWUSR \
		507	or EXT2_S_IRGRP or EXT2_S_IWGRP \
		508	or EXT2_S_IROTH or EXT2_S_IWOTH
		509
		510	; File type defining values in directory entry.
		511	EXT2_FT_REG_FILE = 1 ; Regular file.
		512	EXT2_FT_DIR = 2 ; Directory.
		513
		514	; Flags used by KolibriOS.
		515	FS_FT_HIDDEN = 2
		516	FS_FT_DIR = 0x10 ; Directory.
		517
		518	; ext2 partition flags.
		519	EXT2_RO = 0x01
		520
		521	FS_FT_ASCII = 0 ; Name in ASCII.
		522	FS_FT_UNICODE = 1 ; Name in Unicode.
		523
		524	EXT2_FEATURE_INCOMPAT_FILETYPE = 0x0002 ; Have file type in directory entry.
		525	EXT4_FEATURE_INCOMPAT_EXTENTS = 0x0040 ; Extents.
		526	EXT4_FEATURE_INCOMPAT_FLEX_BG = 0x0200 ; Flexible block groups.
		527
		528	EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER = 0x0001 ; Sparse Superblock
		529	EXT2_FEATURE_RO_COMPAT_LARGE_FILE = 0x0002 ; Large file support (64-bit file size)
		530
		531	; Implemented ext[2,3,4] features.
		532	EXT4_FEATURE_INCOMPAT_SUPP = EXT2_FEATURE_INCOMPAT_FILETYPE \
		533	or EXT4_FEATURE_INCOMPAT_EXTENTS \
		534	or EXT4_FEATURE_INCOMPAT_FLEX_BG
		535
		536	; Implemented features which otherwise require "read-only" mount.
		537	EXT2_FEATURE_RO_COMPAT_SUPP = EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER \
		538	or EXT2_FEATURE_RO_COMPAT_LARGE_FILE
		539
		540	; ext4 features not support for write.
		541	EXT4_FEATURE_INCOMPAT_W_NOT_SUPP = EXT4_FEATURE_INCOMPAT_EXTENTS \
		542	or EXT4_FEATURE_INCOMPAT_FLEX_BG
		543
		544	; Flags specified in i_flags.
		545	EXT2_EXTENTS_FL = 0x00080000 ; Extents.
		546
		547	struct EXT2_INODE_STRUC
		548	i_mode dw ?
		549	i_uid dw ?
		550	i_size dd ?
		551	i_atime dd ?
		552	i_ctime dd ?
		553	i_mtime dd ?
		554	i_dtime dd ?
		555	i_gid dw ?
		556	i_links_count dw ?
		557	i_blocks dd ?
		558	i_flags dd ?
		559	i_osd1 dd ?
		560	i_block rd 15
		561	i_generation dd ?
		562	i_file_acl dd ?
		563	i_dir_acl dd ?
		564	i_faddr dd ?
		565	i_osd2 dd ? ; 12 bytes.
		566	ends
		567
		568	struct EXT2_DIR_STRUC
		569	inode dd ?
		570	rec_len dw ?
		571	name_len db ?
		572	file_type db ?
		573	name db ? ; 255 (max) bytes.
		574	ends
		575
		576	struct EXT2_BLOCK_GROUP_DESC
		577	block_bitmap dd ? ; +0
		578	inode_bitmap dd ? ; +4
		579	inode_table dd ? ; +8
		580	free_blocks_count dw ? ; +12
		581	free_inodes_count dw ? ; +14
		582	used_dirs_count dw ? ; +16
		583	pad dw ? ; +18
		584	reserved rb 12 ; +20
		585	ends
		586
		587	struct EXT2_SB_STRUC
		588	inodes_count dd ? ; +0
		589	blocks_count dd ? ; +4
		590	r_block_count dd ? ; +8
		591	free_block_count dd ? ; +12
		592	free_inodes_count dd ? ; +16
		593	first_data_block dd ? ; +20
		594	log_block_size dd ? ; +24
		595	log_frag_size dd ? ; +28
		596	blocks_per_group dd ? ; +32
		597	frags_per_group dd ? ; +36
		598	inodes_per_group dd ? ; +40
		599	mtime dd ? ; +44
		600	wtime dd ? ; +48
		601	mnt_count dw ? ; +52
		602	max_mnt_count dw ? ; +54
		603	magic dw ? ; +56
		604	state dw ? ; +58
		605	errors dw ? ; +60
		606	minor_rev_level dw ? ; +62
		607	lastcheck dd ? ; +64
		608	check_intervals dd ? ; +68
		609	creator_os dd ? ; +72
		610	rev_level dd ? ; +76
		611	def_resuid dw ? ; +80
		612	def_resgid dw ? ; +82
		613	first_ino dd ? ; +84
		614	inode_size dw ? ; +88
		615	block_group_nr dw ? ; +90
		616	feature_compat dd ? ; +92
		617	feature_incompat dd ? ; +96
		618	feature_ro_compat dd ? ; +100
		619	uuid rb 16 ; +104
		620	volume_name rb 16 ; +120
		621	last_mounted rb 64 ; +136
		622	algo_bitmap dd ? ; +200
		623	prealloc_blocks db ? ; +204
		624	preallock_dir_blocks db ? ; +205
		625	reserved_gdt_blocks dw ? ; +206
		626	journal_uuid rb 16 ; +208
		627	journal_inum dd ? ; +224
		628	journal_dev dd ? ; +228
		629	last_orphan dd ? ; +232
		630	hash_seed rd 4 ; +236
		631	def_hash_version db ? ; +252
		632	reserved rb 3 ; +253 (reserved)
		633	default_mount_options dd ? ; +256
		634	first_meta_bg dd ? ; +260
		635	mkfs_time dd ? ; +264
		636	jnl_blocks rd 17 ; +268
		637	blocks_count_hi dd ? ; +336
		638	r_blocks_count_hi dd ? ; +340
		639	free_blocks_count_hi dd ? ; +344
		640	min_extra_isize dw ? ; +348
		641	want_extra_isize dw ? ; +350
		642	flags dd ? ; +352
		643	raid_stride dw ? ; +356
		644	mmp_interval dw ? ; +358
		645	mmp_block dq ? ; +360
		646	raid_stripe_width dd ? ; +368
		647	log_groups_per_flex db ? ; +372
		648	ends
		649
		650	; Header block extents.
		651	struct EXT4_EXTENT_HEADER
		652	eh_magic dw ? ; Magic value of 0xF30A, for ext4.
		653	eh_entries dw ? ; Number of blocks covered by the extent.
		654	eh_max dw ? ; Capacity of entries.
		655	eh_depth dw ? ; Tree depth (if 0, extents in the array are not extent indexes)
		656	eh_generation dd ? ; ???
		657	ends
		658
		659	; Extent.
		660	struct EXT4_EXTENT
		661	ee_block dd ? ; First logical block extent covers.
		662	ee_len dw ? ; Number of blocks covered by extent.
		663	ee_start_hi dw ? ; Upper 16 bits of 48-bit address (unused in KOS)
		664	ee_start_lo dd ? ; Lower 32 bits of 48-bit address.
		665	ends
		666
		667	; Index on-disk structure; pointer to block of extents/indexes.
		668	struct EXT4_EXTENT_IDX
		669	ei_block dd ? ; Covers logical blocks from here.
		670	ei_leaf_lo dd ? ; Lower 32-bits of pointer to the physical block of the next level.
		671	ei_leaf_hi dw ? ; Higher 16-bits (unused in KOS).
		672	ei_unused dw ? ; Reserved.
		673	ends

Subversion Repositories Kolibri OS

(root)/kernel/branches/kolibri-process/fs/ext2/ext2.inc – Rev 4923