forked from KolibriOS/kolibrios
find all Fat16/32 partition in all input point to MBR
git-svn-id: svn://kolibrios.org@65 a494cfbc-eb01-0410-851d-a64ba20cac60
This commit is contained in:
Marat Zakiyanov (Mario79)
parent
f08ff6ca70
commit
9b016cea47
@ -8,6 +8,8 @@
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;; ;;
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;; See file COPYING for details ;;
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;; ;;
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;; 28.01.2006 find all Fat16/32 partition in all input point ;;
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;; to MBR, see file part_set.inc - Mario79 ;;
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;; 15.01.2005 get file size/attr/date, file_append - ATV ;;
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;; 04.12.2004 skip volume label, file delete bug fixed - ATV ;;
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;; 29.11.2004 get_free_FAT changed, append dir bug fixed - ATV ;;
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@ -51,36 +53,6 @@ PUSHAD_EBP equ [esp+8]
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PUSHAD_ESI equ [esp+4]
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PUSHAD_EDI equ [esp+0]
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align 4
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;******************************************************
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; Please do not change this place - variables in text
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; Mario79
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; START place
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;******************************************************
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PARTITION_START dd 0x3f
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PARTITION_END dd 0
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SECTORS_PER_FAT dd 0x1f3a
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NUMBER_OF_FATS dd 0x2
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SECTORS_PER_CLUSTER dd 0x8
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BYTES_PER_SECTOR dd 0x200 ; Note: if BPS <> 512 need lots of changes
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ROOT_CLUSTER dd 2 ; first rootdir cluster
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FAT_START dd 0 ; start of fat table
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ROOT_START dd 0 ; start of rootdir (only fat16)
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ROOT_SECTORS dd 0 ; count of rootdir sectors (only fat16)
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DATA_START dd 0 ; start of data area (=first cluster 2)
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LAST_CLUSTER dd 0 ; last availabe cluster
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ADR_FSINFO dd 0 ; used only by fat32
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fatRESERVED dd 0x0FFFFFF6
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fatBAD dd 0x0FFFFFF7
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fatEND dd 0x0FFFFFF8
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fatMASK dd 0x0FFFFFFF
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fat_type db 0 ; 0=none, 16=fat16, 32=fat32
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;***************************************************************************
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; End place
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; Mario79
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;***************************************************************************
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cluster dd 0 ; used by file_write,makedir,append
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partition_count dd 0 ; partitions found by set_FAT32_variables
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longname_sec1 dd 0 ; used by analyze_directory to save 2 previous
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@ -131,38 +103,6 @@ uglobal
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endg
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iglobal
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partition_types: ; list of fat16/32 partitions
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db 0x04 ; DOS: fat16 <32M
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db 0x06 ; DOS: fat16 >32M
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db 0x0b ; WIN95: fat32
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db 0x0c ; WIN95: fat32, LBA-mapped
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db 0x0e ; WIN95: fat16, LBA-mapped
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db 0x14 ; Hidden DOS: fat16 <32M
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db 0x16 ; Hidden DOS: fat16 >32M
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db 0x1b ; Hidden WIN95: fat32
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db 0x1c ; Hidden WIN95: fat32, LBA-mapped
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db 0x1e ; Hidden WIN95: fat16, LBA-mapped
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db 0xc4 ; DRDOS/secured: fat16 <32M
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db 0xc6 ; DRDOS/secured: fat16 >32M
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db 0xcb ; DRDOS/secured: fat32
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db 0xcc ; DRDOS/secured: fat32, LBA-mapped
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db 0xce ; DRDOS/secured: fat16, LBA-mapped
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db 0xd4 ; Old Multiuser DOS secured: fat16 <32M
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db 0xd6 ; Old Multiuser DOS secured: fat16 >32M
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partition_types_end:
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extended_types: ; list of extended partitions
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db 0x05 ; DOS: extended partition
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db 0x0f ; WIN95: extended partition, LBA-mapped
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db 0xc5 ; DRDOS/secured: extended partition
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db 0xd5 ; Old Multiuser DOS secured: extended partition
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extended_types_end:
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endg
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reserve_hd1:
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cli
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@ -201,197 +141,7 @@ clear_hd_cache:
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problem_partition db 0 ; used for partitions search
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; Partition chain used:
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; MBR ; PARTITION2 ; PARTITION3 ; PARTITION4
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;==========================================================
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; fat16/32 +-- fat16/32 +-- fat16/32 +-- fat16/32 +--
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; extended --+ extended --+ extended --+ extended --+
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; 0 0 0 0
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; 0 0 0 0
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; Notes:
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; - extended partition need to be in second entry on table
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; - it will skip over removed partitions
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set_FAT32_variables:
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mov [0xfe10],dword 0 ; entries in hd cache
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mov [problem_partition],0
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call reserve_hd1
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call clear_hd_cache
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cmp dword [hdpos],0
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je problem_hd
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pushad
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xor ecx,ecx ; partition count
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mov edx,-1 ; flag for partition
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xor eax,eax ; read MBR
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xor ebp,ebp ; extended partition start
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new_partition:
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test ebp,ebp ; is there extended partition?
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jnz extended_already_set ; yes
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xchg ebp,eax ; no. set it now
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extended_already_set:
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add eax,ebp ; mbr=mbr+0, ext_part=ext_start+relat_start
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mov ebx,buffer
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call hd_read
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cmp word [ebx+0x1fe],0xaa55 ; is it valid boot sector?
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jnz end_partition_chain
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cmp dword [ebx+0x1be+0xc],0 ; skip over empty partition
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jz next_partition
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push eax ecx
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mov edi,partition_types
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mov ecx,partition_types_end-partition_types
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mov al,[ebx+0x1be+4] ; get partition type
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cld
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repne scasb ; is partition type ok?
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pop ecx eax
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jnz next_partition ; no. skip over
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inc ecx
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cmp ecx,[fat32part] ; is it wanted partition?
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jnz next_partition ; no
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mov edx,eax ; start sector
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add edx,[ebx+0x1be+8] ; add relative start
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next_partition:
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push ecx
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mov edi,extended_types
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mov ecx,extended_types_end-extended_types
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mov al,[ebx+0x1be+4+16] ; get second partition type
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cld
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repne scasb ; is it extended partition?
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pop ecx
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jnz end_partition_chain ; no. end chain
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mov eax,[ebx+0x1be+8+16] ; get start of extended partition
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test eax,eax ; is there extended partition?
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jnz new_partition ; yes. read it
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end_partition_chain:
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mov [partition_count],ecx
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cmp edx,-1 ; found wanted partition?
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jnz hd_and_partition_ok ; yes. install it
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jmp problem_partition_or_fat
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problem_fat_dec_count: ; bootsector is missing or another problem
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dec [partition_count] ; remove it from partition_count
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problem_partition_or_fat:
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popad
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problem_hd:
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mov [fat_type],0
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mov [hd1_status],0 ; free
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mov [problem_partition],1
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ret
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hd_and_partition_ok:
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mov eax,edx
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mov [PARTITION_START],eax
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mov [hd_setup],1
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mov ebx,buffer
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call hd_read ; read boot sector of partition
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mov [hd_setup],0
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cmp word [ebx+0x1fe],0xaa55 ; is it valid boot sector?
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jnz problem_fat_dec_count
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movzx eax,word [ebx+0xe] ; sectors reserved
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add eax,[PARTITION_START]
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mov [FAT_START],eax ; fat_start = partition_start + reserved
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movzx eax,byte [ebx+0xd] ; sectors per cluster
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mov [SECTORS_PER_CLUSTER],eax
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movzx ecx,word [ebx+0xb] ; bytes per sector
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mov [BYTES_PER_SECTOR],ecx
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movzx eax,word [ebx+0x11] ; count of rootdir entries (=0 fat32)
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mov edx,32
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mul edx
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dec ecx
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add eax,ecx ; round up if not equal count
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inc ecx ; bytes per sector
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div ecx
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mov [ROOT_SECTORS],eax ; count of rootdir sectors
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movzx eax,word [ebx+0x16] ; sectors per fat <65536
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test eax,eax
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jnz fat16_fatsize
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mov eax,[ebx+0x24] ; sectors per fat
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fat16_fatsize:
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mov [SECTORS_PER_FAT],eax
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movzx eax,byte [ebx+0x10] ; number of fats
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test eax,eax ; if 0 it's not fat partition
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jz problem_fat_dec_count
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mov [NUMBER_OF_FATS],eax
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imul eax,[SECTORS_PER_FAT]
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add eax,[FAT_START]
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mov [ROOT_START],eax ; rootdir = fat_start + fat_size * fat_count
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add eax,[ROOT_SECTORS] ; rootdir sectors should be 0 on fat32
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mov [DATA_START],eax ; data area = rootdir + rootdir_size
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movzx eax,word [ebx+0x13] ; total sector count <65536
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test eax,eax
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jnz fat16_total
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mov eax,[ebx+0x20] ; total sector count
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fat16_total:
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add eax,[PARTITION_START]
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dec eax
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mov [PARTITION_END],eax
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inc eax
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sub eax,[DATA_START] ; eax = count of data sectors
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xor edx,edx
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div dword [SECTORS_PER_CLUSTER]
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inc eax
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mov [LAST_CLUSTER],eax
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dec eax ; cluster count
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; limits by Microsoft Hardware White Paper v1.03
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cmp eax,4085 ; 0xff5
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jb problem_fat_dec_count ; fat12 not supported
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cmp eax,65525 ; 0xfff5
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jb fat16_partition
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fat32_partition:
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mov eax,[ebx+0x2c] ; rootdir cluster
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mov [ROOT_CLUSTER],eax
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movzx eax,word [ebx+0x30] ; fs info sector
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add eax,[PARTITION_START]
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mov [ADR_FSINFO],eax
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popad
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mov [fatRESERVED],0x0FFFFFF6
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mov [fatBAD],0x0FFFFFF7
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mov [fatEND],0x0FFFFFF8
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mov [fatMASK],0x0FFFFFFF
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mov [fat_type],32 ; Fat32
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mov [hd1_status],0 ; free
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ret
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fat16_partition:
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xor eax,eax
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mov [ROOT_CLUSTER],eax
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popad
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mov [fatRESERVED],0x0000FFF6
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mov [fatBAD],0x0000FFF7
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mov [fatEND],0x0000FFF8
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mov [fatMASK],0x0000FFFF
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mov [fat_type],16 ; Fat16
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mov [hd1_status],0 ; free
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ret
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include 'part_set.inc'
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set_FAT:
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;--------------------------------
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344
kernel/trunk/fs/part_set.inc
Normal file
344
kernel/trunk/fs/part_set.inc
Normal file
@ -0,0 +1,344 @@
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;*************************************************************
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;* 28.01.2006 find all Fat16/32 partition in all input point *
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;* to MBR - Mario79 *
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;*************************************************************
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align 4
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;******************************************************
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; Please do not change this place - variables in text
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; Mario79
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; START place
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;******************************************************
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PARTITION_START dd 0x3f
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PARTITION_END dd 0
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SECTORS_PER_FAT dd 0x1f3a
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NUMBER_OF_FATS dd 0x2
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SECTORS_PER_CLUSTER dd 0x8
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BYTES_PER_SECTOR dd 0x200 ; Note: if BPS <> 512 need lots of changes
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ROOT_CLUSTER dd 2 ; first rootdir cluster
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FAT_START dd 0 ; start of fat table
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ROOT_START dd 0 ; start of rootdir (only fat16)
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ROOT_SECTORS dd 0 ; count of rootdir sectors (only fat16)
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DATA_START dd 0 ; start of data area (=first cluster 2)
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LAST_CLUSTER dd 0 ; last availabe cluster
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ADR_FSINFO dd 0 ; used only by fat32
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fatRESERVED dd 0x0FFFFFF6
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fatBAD dd 0x0FFFFFF7
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fatEND dd 0x0FFFFFF8
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fatMASK dd 0x0FFFFFFF
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fat_type db 0 ; 0=none, 16=fat16, 32=fat32
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;***************************************************************************
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; End place
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; Mario79
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;***************************************************************************
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iglobal
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partition_types: ; list of fat16/32 partitions
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db 0x04 ; DOS: fat16 <32M
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db 0x06 ; DOS: fat16 >32M
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db 0x0b ; WIN95: fat32
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db 0x0c ; WIN95: fat32, LBA-mapped
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db 0x0e ; WIN95: fat16, LBA-mapped
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db 0x14 ; Hidden DOS: fat16 <32M
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db 0x16 ; Hidden DOS: fat16 >32M
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db 0x1b ; Hidden WIN95: fat32
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db 0x1c ; Hidden WIN95: fat32, LBA-mapped
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db 0x1e ; Hidden WIN95: fat16, LBA-mapped
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db 0xc4 ; DRDOS/secured: fat16 <32M
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db 0xc6 ; DRDOS/secured: fat16 >32M
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db 0xcb ; DRDOS/secured: fat32
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db 0xcc ; DRDOS/secured: fat32, LBA-mapped
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db 0xce ; DRDOS/secured: fat16, LBA-mapped
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db 0xd4 ; Old Multiuser DOS secured: fat16 <32M
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db 0xd6 ; Old Multiuser DOS secured: fat16 >32M
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partition_types_end:
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extended_types: ; list of extended partitions
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db 0x05 ; DOS: extended partition
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db 0x0f ; WIN95: extended partition, LBA-mapped
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db 0xc5 ; DRDOS/secured: extended partition
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db 0xd5 ; Old Multiuser DOS secured: extended partition
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extended_types_end:
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endg
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; Partition chain used:
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; MBR ; PARTITION2 ; PARTITION3 ; PARTITION4
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;==========================================================
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; fat16/32 +-- fat16/32 +-- fat16/32 +-- fat16/32 +--
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; extended --+ extended --+ extended --+ extended --+
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; 0 0 0 0
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; 0 0 0 0
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; Notes:
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; - extended partition need to be in second entry on table
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; - it will skip over removed partitions
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set_FAT32_variables:
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mov [0xfe10],dword 0 ; entries in hd cache
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mov [problem_partition],0
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call reserve_hd1
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call clear_hd_cache
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cmp dword [hdpos],0
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je problem_hd
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pushad
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xor ecx,ecx ; partition count
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mov edx,-1 ; flag for partition
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xor eax,eax ; read MBR
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xor ebp,ebp ; extended partition start
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new_partition:
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test ebp,ebp ; is there extended partition?
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jnz extended_already_set ; yes
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xchg ebp,eax ; no. set it now
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extended_already_set:
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add eax,ebp ; mbr=mbr+0, ext_part=ext_start+relat_start
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mov ebx,buffer
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call hd_read
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cmp word [ebx+0x1fe],0xaa55 ; is it valid boot sector?
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jnz end_partition_chain
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cmp dword [ebx+0x1be+0xc],0 ; skip over empty partition
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jz next_partition
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push eax
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mov al,[ebx+0x1be+4] ; get primary partition type
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call scan_partition_types
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pop eax
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jnz next_primary_partition ; no. skip over
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inc ecx
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cmp ecx,[fat32part] ; is it wanted partition?
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jnz next_primary_partition ; no
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mov edx,eax ; start sector
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add edx,[ebx+0x1be+8] ; add relative start
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next_primary_partition:
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push eax
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mov al,[ebx+0x1be+4+16] ; get primary partition type
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call scan_partition_types
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pop eax
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jnz next_primary_partition_1 ; no. skip over
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inc ecx
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cmp ecx,[fat32part] ; is it wanted partition?
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jnz next_primary_partition_1 ; no
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mov edx,eax ; start sector
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add edx,[ebx+0x1be+8+16] ; add relative start
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next_primary_partition_1:
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push eax
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mov al,[ebx+0x1be+4+16+16] ; get primary partition type
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call scan_partition_types
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pop eax
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jnz next_primary_partition_2 ; no. skip over
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inc ecx
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cmp ecx,[fat32part] ; is it wanted partition?
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jnz next_primary_partition_2 ; no
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mov edx,eax ; start sector
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add edx,[ebx+0x1be+8+16+16] ; add relative start
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next_primary_partition_2:
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push eax
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mov al,[ebx+0x1be+4+16+16+16] ; get primary partition type
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call scan_partition_types
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pop eax
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jnz next_partition ; no. skip over
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inc ecx
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cmp ecx,[fat32part] ; is it wanted partition?
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jnz next_partition ; no
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mov edx,eax ; start sector
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add edx,[ebx+0x1be+8+16+16+16] ; add relative start
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next_partition:
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push eax
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mov al,[ebx+0x1be+4] ; get extended partition type
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call scan_extended_types
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pop eax
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jnz next_partition_1
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mov eax,[ebx+0x1be+8] ; add relative start
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test eax,eax ; is there extended partition?
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jnz new_partition ; yes. read it
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next_partition_1:
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push eax
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mov al,[ebx+0x1be+4+16] ; get extended partition type
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call scan_extended_types
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pop eax
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jnz next_partition_2
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|
||||
mov eax,[ebx+0x1be+8+16] ; add relative start
|
||||
test eax,eax ; is there extended partition?
|
||||
jnz new_partition ; yes. read it
|
||||
|
||||
next_partition_2:
|
||||
push eax
|
||||
mov al,[ebx+0x1be+4+16+16] ; get extended partition type
|
||||
call scan_extended_types
|
||||
pop eax
|
||||
jnz next_partition_3
|
||||
|
||||
mov eax,[ebx+0x1be+8+16+16] ; add relative start
|
||||
test eax,eax ; is there extended partition?
|
||||
jnz new_partition ; yes. read it
|
||||
|
||||
next_partition_3:
|
||||
push eax
|
||||
mov al,[ebx+0x1be+4+16+16+16] ; get extended partition type
|
||||
call scan_extended_types
|
||||
pop eax
|
||||
jnz end_partition_chain ; no. end chain
|
||||
|
||||
mov eax,[ebx+0x1be+8+16+16+16] ; get start of extended partition
|
||||
test eax,eax ; is there extended partition?
|
||||
jnz new_partition ; yes. read it
|
||||
|
||||
end_partition_chain:
|
||||
mov [partition_count],ecx
|
||||
|
||||
cmp edx,-1 ; found wanted partition?
|
||||
jnz hd_and_partition_ok ; yes. install it
|
||||
jmp problem_partition_or_fat
|
||||
|
||||
scan_partition_types:
|
||||
push ecx
|
||||
mov edi,partition_types
|
||||
mov ecx,partition_types_end-partition_types
|
||||
cld
|
||||
repne scasb ; is partition type ok?
|
||||
pop ecx
|
||||
ret
|
||||
|
||||
scan_extended_types:
|
||||
push ecx
|
||||
mov edi,extended_types
|
||||
mov ecx,extended_types_end-extended_types
|
||||
cld
|
||||
repne scasb ; is it extended partition?
|
||||
pop ecx
|
||||
ret
|
||||
|
||||
problem_fat_dec_count: ; bootsector is missing or another problem
|
||||
dec [partition_count] ; remove it from partition_count
|
||||
|
||||
problem_partition_or_fat:
|
||||
popad
|
||||
|
||||
problem_hd:
|
||||
mov [fat_type],0
|
||||
mov [hd1_status],0 ; free
|
||||
mov [problem_partition],1
|
||||
ret
|
||||
|
||||
hd_and_partition_ok:
|
||||
mov eax,edx
|
||||
mov [PARTITION_START],eax
|
||||
|
||||
mov [hd_setup],1
|
||||
mov ebx,buffer
|
||||
call hd_read ; read boot sector of partition
|
||||
mov [hd_setup],0
|
||||
|
||||
cmp word [ebx+0x1fe],0xaa55 ; is it valid boot sector?
|
||||
jnz problem_fat_dec_count
|
||||
|
||||
movzx eax,word [ebx+0xe] ; sectors reserved
|
||||
add eax,[PARTITION_START]
|
||||
mov [FAT_START],eax ; fat_start = partition_start + reserved
|
||||
|
||||
movzx eax,byte [ebx+0xd] ; sectors per cluster
|
||||
mov [SECTORS_PER_CLUSTER],eax
|
||||
|
||||
movzx ecx,word [ebx+0xb] ; bytes per sector
|
||||
mov [BYTES_PER_SECTOR],ecx
|
||||
|
||||
movzx eax,word [ebx+0x11] ; count of rootdir entries (=0 fat32)
|
||||
mov edx,32
|
||||
mul edx
|
||||
dec ecx
|
||||
add eax,ecx ; round up if not equal count
|
||||
inc ecx ; bytes per sector
|
||||
div ecx
|
||||
mov [ROOT_SECTORS],eax ; count of rootdir sectors
|
||||
|
||||
movzx eax,word [ebx+0x16] ; sectors per fat <65536
|
||||
test eax,eax
|
||||
jnz fat16_fatsize
|
||||
mov eax,[ebx+0x24] ; sectors per fat
|
||||
fat16_fatsize:
|
||||
mov [SECTORS_PER_FAT],eax
|
||||
|
||||
movzx eax,byte [ebx+0x10] ; number of fats
|
||||
test eax,eax ; if 0 it's not fat partition
|
||||
jz problem_fat_dec_count
|
||||
mov [NUMBER_OF_FATS],eax
|
||||
imul eax,[SECTORS_PER_FAT]
|
||||
add eax,[FAT_START]
|
||||
mov [ROOT_START],eax ; rootdir = fat_start + fat_size * fat_count
|
||||
add eax,[ROOT_SECTORS] ; rootdir sectors should be 0 on fat32
|
||||
mov [DATA_START],eax ; data area = rootdir + rootdir_size
|
||||
|
||||
movzx eax,word [ebx+0x13] ; total sector count <65536
|
||||
test eax,eax
|
||||
jnz fat16_total
|
||||
mov eax,[ebx+0x20] ; total sector count
|
||||
fat16_total:
|
||||
add eax,[PARTITION_START]
|
||||
dec eax
|
||||
mov [PARTITION_END],eax
|
||||
inc eax
|
||||
sub eax,[DATA_START] ; eax = count of data sectors
|
||||
xor edx,edx
|
||||
div dword [SECTORS_PER_CLUSTER]
|
||||
inc eax
|
||||
mov [LAST_CLUSTER],eax
|
||||
dec eax ; cluster count
|
||||
|
||||
; limits by Microsoft Hardware White Paper v1.03
|
||||
cmp eax,4085 ; 0xff5
|
||||
jb problem_fat_dec_count ; fat12 not supported
|
||||
cmp eax,65525 ; 0xfff5
|
||||
jb fat16_partition
|
||||
|
||||
fat32_partition:
|
||||
mov eax,[ebx+0x2c] ; rootdir cluster
|
||||
mov [ROOT_CLUSTER],eax
|
||||
movzx eax,word [ebx+0x30] ; fs info sector
|
||||
add eax,[PARTITION_START]
|
||||
mov [ADR_FSINFO],eax
|
||||
|
||||
popad
|
||||
|
||||
mov [fatRESERVED],0x0FFFFFF6
|
||||
mov [fatBAD],0x0FFFFFF7
|
||||
mov [fatEND],0x0FFFFFF8
|
||||
mov [fatMASK],0x0FFFFFFF
|
||||
mov [fat_type],32 ; Fat32
|
||||
mov [hd1_status],0 ; free
|
||||
ret
|
||||
|
||||
fat16_partition:
|
||||
xor eax,eax
|
||||
mov [ROOT_CLUSTER],eax
|
||||
|
||||
popad
|
||||
|
||||
mov [fatRESERVED],0x0000FFF6
|
||||
mov [fatBAD],0x0000FFF7
|
||||
mov [fatEND],0x0000FFF8
|
||||
mov [fatMASK],0x0000FFFF
|
||||
mov [fat_type],16 ; Fat16
|
||||
mov [hd1_status],0 ; free
|
||||
ret
|
||||
Loading…
Reference in New Issue
Block a user