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[FAT32]

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- Really fix loading the MSVC built kernel, by moving the FAT sector buffer beyond the area for freeldr.sys
- Load segment only in one place

svn path=/trunk/; revision=52500
This commit is contained in:
Timo Kreuzer 2011-07-02 15:08:54 +00:00
parent 7bff316a9a
commit b062ee8583
1 changed files with 7 additions and 14 deletions
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21
reactos/boot/freeldr/bootsect/fat32.S
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@ -153,6 +153,7 @@ LoadExtraBootCode:
// EAX has logical sector number to read
// CX has number of sectors to read
ReadSectors:
push es
cmp eax, dword ptr ds:[BiosCHSDriveSize] // Check if they are reading a sector outside CHS range
jae ReadSectorsLBA // Yes - go to the LBA routine
// If at all possible we want to use LBA routines because
@ -194,13 +195,6 @@ ReadSectorsSetupDiskAddressPacket:
mov dl, byte ptr BP_REL(BootDrive) // Drive number
mov ah, HEX(42) // Int 13h, AH = 42h - Extended Read
int HEX(13) // Call BIOS
/* This code "fixes" loading the MSVC built kernel */
pushad
mov si, offset msgNull
call PutChars
popad
jc PrintDiskError // If the read failed then abort
add sp, 16 // Remove disk address packet from stack
@ -219,6 +213,7 @@ ReadSectorsSetupDiskAddressPacket:
sub cx, word ptr ds:[LBASectorsRead]
jnz ReadSectorsLBA // Read next sector
pop es
ret
LBASectorsRead:
@ -309,8 +304,6 @@ msgFileSystemError:
.ascii "File system error", CR, LF, NUL
msgAnyKey:
.ascii "Press any key to restart", CR, LF, NUL
msgNull:
.ascii NUL
.org 509 // Pad to 509 bytes
@ -473,21 +466,21 @@ GetActiveFatOffset:
LoadFatSector:
push ecx
mov bx, HEX(9000) // We will load it to [9000:0000h]
mov es, bx
// EAX holds logical FAT sector number
// Check if we have already loaded it
cmp eax, dword ptr ds:[FatSectorInCache]
je LoadFatSectorAlreadyLoaded
mov dword ptr ds:[FatSectorInCache], eax
mov bx, HEX(7000)
mov es, bx
xor bx, bx // We will load it to [7000:0000h]
xor bx, bx
mov cx, 1
call ReadSectors
LoadFatSectorAlreadyLoaded:
mov bx, HEX(7000)
mov es, bx
pop ecx
mov eax, dword ptr es:[ecx] // Get FAT entry
and eax, HEX(0fffffff) // Mask off reserved bits