More cleanups; try to get rid of the now-obsolete definition of

"cluster" as the minimum block

diff --git a/comboot.inc b/comboot.inc
index f3aec3b..af34686 100644 (file)
--- a/comboot.inc
+++ b/comboot.inc
@@ -125,7 +125,8 @@ is_comboot_image:
                ; Now actually load the file...
                pop si                  ; File handle
                mov bx,100h             ; Load at <seg>:0100h
-               mov cx,[ClustPerMoby]   ; Absolute maximum # of clusters
+               mov cx,0FF00h >> SECTOR_SHIFT
+                                       ; Absolute maximum # of sectors
                call getfssec
 
                ; And invoke the program...
@@ -420,8 +421,7 @@ comapi_open:
                jz .err
                mov P_AX,ax
                mov P_HAX,dx
-               mov ax,[ClustSize]
-               mov P_CX,ax
+               mov P_CX,SECTOR_SIZE
                mov P_SI,si
                clc
                ret

diff --git a/getc.inc b/getc.inc
index 4ec9757..6fd2406 100644 (file)
--- a/getc.inc
+++ b/getc.inc
@@ -38,12 +38,10 @@ openfd:
                pushf
                mov [FBytes1],ax
                mov [FBytes2],dx
-               add ax,[ClustSize]
-               adc dx,byte 0
-               sub ax,byte 1
-               sbb dx,byte 0
-               div word [ClustSize]
-               mov [FClust],ax         ; Number of clusters
+               mov eax,[FBytes]
+               add eax,SECTOR_SIZE-1
+               shr eax,SECTOR_SHIFT
+               mov [FSectors],eax      ; Number of sectors
                mov [FNextClust],si     ; Cluster pointer
                mov ax,[EndOfGetCBuf]   ; Pointer at end of buffer ->
                mov [FPtr],ax           ;  nothing loaded yet
@@ -58,11 +56,11 @@ getc:
                cmp si,[EndOfGetCBuf]
                jb getc_loaded
                ; Buffer empty -- load another set
-               mov cx,[FClust]
-               cmp cx,[BufSafe]
+               mov ecx,[FSectors]
+               cmp ecx,trackbufsize >> SECTOR_SHIFT
                jna getc_oksize
-               mov cx,[BufSafe]
-getc_oksize:   sub [FClust],cx         ; Reduce remaining clusters
+               mov ecx,trackbufsize >> SECTOR_SHIFT
+getc_oksize:   sub [FSectors],ecx      ; Reduce remaining clusters
                mov si,[FNextClust]
                push es                 ; ES may be != DS, save old ES
                push ds

diff --git a/isolinux.asm b/isolinux.asm
index 14d5d58..ad181b6 100644 (file)
--- a/isolinux.asm
+++ b/isolinux.asm
@@ -37,8 +37,8 @@ retry_count   equ 6                   ; How patient are we with the BIOS?
 %assign HIGHMEM_SLOP 128*1024          ; Avoid this much memory near the top
 MAX_OPEN_LG2   equ 6                   ; log2(Max number of open files)
 MAX_OPEN       equ (1 << MAX_OPEN_LG2)
-SECTORSIZE_LG2 equ 11                  ; 2048 bytes/sector (El Torito requirement)
-SECTORSIZE     equ (1 << SECTORSIZE_LG2)
+SECTOR_SHIFT   equ 11                  ; 2048 bytes/sector (El Torito requirement)
+SECTOR_SIZE    equ (1 << SECTOR_SHIFT)
 
 ;
 ; This is what we need to do when idle
@@ -161,16 +161,16 @@ RamdiskMax        resd 1                  ; Highest address for a ramdisk
 KernelSize     resd 1                  ; Size of kernel (bytes)
 SavedSSSP      resd 1                  ; Our SS:SP while running a COMBOOT image
 PMESP          resd 1                  ; Protected-mode ESP
+FSectors       resd 1                  ; Number of sectors in getc file
 RootDir                resb dir_t_size         ; Root directory
 CurDir         resb dir_t_size         ; Current directory
-KernelClust    resd 1                  ; Kernel size in clusters
+KernelSects    resd 1                  ; Kernel size in clusters
 InitStack      resd 1                  ; Initial stack pointer (SS:SP)
 FirstSecSum    resd 1                  ; Checksum of bytes 64-2048
 ImageDwords    resd 1                  ; isolinux.bin size, dwords
 FBytes         equ $                   ; Used by open/getc
 FBytes1                resw 1
 FBytes2                resw 1
-FClust         resw 1                  ; Number of clusters in open/getc file
 FNextClust     resw 1                  ; Pointer to next cluster in d:o
 FPtr           resw 1                  ; Pointer to next char in buffer
 CmdOptPtr       resw 1                 ; Pointer to first option on cmd line
@@ -277,7 +277,7 @@ _start1:    mov [cs:InitStack],sp           ; Save initial stack pointer
                ;
 initial_csum:  xor edi,edi
                mov si,_start1
-               mov cx,(SECTORSIZE-64) >> 2
+               mov cx,(SECTOR_SIZE-64) >> 2
 .loop:         lodsd
                add edi,eax
                loop .loop
@@ -363,7 +363,7 @@ set_file:
 found_file:
                ; Set up boot file sizes
                mov eax,[bi_length]
-               sub eax,SECTORSIZE-3
+               sub eax,SECTOR_SIZE-3
                shr eax,2                       ; bytes->dwords
                mov [ImageDwords],eax           ; boot file dwords
                add eax,(2047 >> 2)
@@ -696,7 +696,7 @@ getlinsec:
                movzx eax,word [si+2]           ; Sectors we read
                add [si+8],eax                  ; Advance sector pointer
                sub bp,ax                       ; Sectors left
-               shl ax,SECTORSIZE_LG2-4         ; 2048-byte sectors -> segment
+               shl ax,SECTOR_SHIFT-4           ; 2048-byte sectors -> segment
                add [si+6],ax                   ; Advance buffer pointer
                and bp,bp
                jnz .loop
@@ -967,8 +967,8 @@ get_fs_structures:
                mov eax,[trackbuf+156+10]
                mov [RootDir+dir_len],eax               
                mov [CurDir+dir_len],eax
-               add eax,SECTORSIZE-1
-               shr eax,SECTORSIZE_LG2
+               add eax,SECTOR_SIZE-1
+               shr eax,SECTOR_SHIFT
                mov [RootDir+dir_clust],eax
                mov [CurDir+dir_clust],eax
 
@@ -1359,8 +1359,8 @@ searchdir_iso:
 
 .next_sector:
                ; Advance to the beginning of next sector
-               lea ax,[si+SECTORSIZE-1]
-               and ax,~(SECTORSIZE-1)
+               lea ax,[si+SECTOR_SIZE-1]
+               and ax,~(SECTOR_SIZE-1)
                sub ax,si
                jmp short .not_file             ; We still need to do length checks
 
@@ -1374,8 +1374,8 @@ searchdir_iso:
                mov [bx+file_sector],eax
                mov eax,[si+10]                 ; Data length
                push eax
-               add eax,SECTORSIZE-1
-               shr eax,SECTORSIZE_LG2
+               add eax,SECTOR_SIZE-1
+               shr eax,SECTOR_SHIFT
                mov [bx+file_left],eax
                pop eax
                mov edx,eax
@@ -1739,16 +1739,13 @@ dsp_dummy:      db 0                            ; Scratch, safe to overwrite
 ; **** BIOS expects our "sector size" to be.
 ;
                alignb 4, db 0
-ClustSize      dd SECTORSIZE           ; Bytes/cluster
-ClustPerMoby   dd 65536/SECTORSIZE     ; Clusters per 64K
-SecPerClust    dw 1                    ; Same as bsSecPerClust, but a word
-BufSafe                dw trackbufsize/SECTORSIZE      ; Clusters we can load into trackbuf
-BufSafeSec     dw trackbufsize/SECTORSIZE      ; = how many sectors?
+BufSafe                dw trackbufsize/SECTOR_SIZE     ; Clusters we can load into trackbuf
+BufSafeSec     dw trackbufsize/SECTOR_SIZE     ; = how many sectors?
 BufSafeBytes   dw trackbufsize         ; = how many bytes?
 EndOfGetCBuf   dw getcbuf+trackbufsize ; = getcbuf+BufSafeBytes
 %ifndef DEPEND
-%if ( trackbufsize % SECTORSIZE ) != 0
-%error trackbufsize must be a multiple of SECTORSIZE
+%if ( trackbufsize % SECTOR_SIZE ) != 0
+%error trackbufsize must be a multiple of SECTOR_SIZE
 %endif
 %endif
 

diff --git a/ldlinux.asm b/ldlinux.asm
index 79d668c..54ece59 100644 (file)
--- a/ldlinux.asm
+++ b/ldlinux.asm
@@ -144,7 +144,8 @@ SuperInfo   equ $
                resq 16                 ; The first 16 bytes expanded 8 times
 
 FAT            resd 1                  ; Location of (first) FAT
-RootDir                resd 1                  ; Location of root directory
+RootDirArea    resd 1                  ; Location of root directory area
+RootDir                resd 1                  ; Location of root directory proper
 DataArea       resd 1                  ; Location of data area
 RootDirSize    resd 1                  ; Root dir size in sectors
 TotalSectors   resd 1                  ; Total number of sectors
@@ -160,6 +161,7 @@ RamdiskMax  resd 1                  ; Highest address for a ramdisk
 KernelSize     resd 1                  ; Size of kernel (bytes)
 SavedSSSP      resd 1                  ; Our SS:SP while running a COMBOOT image
 PMESP          resd 1                  ; Protected-mode ESP
+FSectors       resd 1                  ; Number of sectors in getc file
 ClustPerMoby   resd 1                  ; Clusters per 64K
 ClustSize      resd 1                  ; Bytes/cluster
 ClustMask      resd 1                  ; Sectors/cluster - 1
@@ -171,12 +173,7 @@ FBytes1            resw 1
 FBytes2                resw 1
 DirBlocksLeft  resw 1                  ; Ditto
 RunLinClust    resw 1                  ; Cluster # for LDLINUX.SYS
-BufSafe                resw 1                  ; Clusters we can load into trackbuf
-BufSafeSec     resw 1                  ; = how many sectors?
-BufSafeBytes   resw 1                  ; = how many bytes?
-EndOfGetCBuf   resw 1                  ; = getcbuf+BufSafeBytes
-KernelClust    resw 1                  ; Kernel size in clusters
-FClust         resw 1                  ; Number of clusters in open/getc file
+KernelSects    resw 1                  ; Kernel size in clusters
 FNextClust     resw 1                  ; Pointer to next cluster in d:o
 FPtr           resw 1                  ; Pointer to next char in buffer
 CmdOptPtr       resw 1                 ; Pointer to first option on cmd line
@@ -890,7 +887,8 @@ genfatinfo:
 .have_fatsecs:
                imul edx,[bxFATs]
                add eax,edx
-               mov [RootDir],eax               ; Beginning of root directory
+               mov [RootDirArea],eax           ; Beginning of root directory
+               mov [RootDir],eax               ; For FAT12/16 == root dir location
 
                mov edx,[bxRootDirEnts]
                add dx,512-32
@@ -926,6 +924,15 @@ getfattype:
                mov cl,nextcluster_fat16-(nextcluster+2)
                cmp eax,65525                   ; FAT16 limit
                jb .setsize
+               ;
+               ; FAT32, root directory is a cluster chain
+               ;
+               mov cl,[ClustShift]
+               mov eax,[bootsec+44]            ; Root directory cluster
+               sub eax,2
+               shl eax,cl
+               add eax,[DataArea]
+               mov [RootDir],eax
                mov cl,nextcluster_fat28-(nextcluster+2)
 .setsize:
                mov byte [nextcluster+1],cl
@@ -1302,7 +1309,6 @@ getfssec_edx:
                jc .do_read
                cmp edx,eax
                jz .getseccnt
-
 .do_read:
                mov eax,edx
                call getlinsecsr
@@ -1318,7 +1324,6 @@ getfssec_edx:
                pop eax
                pop ebp
                ret
-
 .eof:
                xor edx,edx
                stc
@@ -1651,6 +1656,17 @@ SerialPort       dw 0                    ; Serial port base (or 0 for no serial port)
 VGAFontSize    dw 16                   ; Defaults to 16 byte font
 UserFont       db 0                    ; Using a user-specified font
 ScrollAttribute        db 07h                  ; White on black (for text mode)
+
+               alignb 4, db 0
+BufSafe                dw trackbufsize/SECTOR_SIZE     ; Clusters we can load into trackbuf
+BufSafeSec     dw trackbufsize/SECTOR_SIZE     ; = how many sectors?
+BufSafeBytes   dw trackbufsize         ; = how many bytes?
+EndOfGetCBuf   dw getcbuf+trackbufsize ; = getcbuf+BufSafeBytes
+%ifndef DEPEND
+%if ( trackbufsize % SECTOR_SIZE ) != 0
+%error trackbufsize must be a multiple of SECTOR_SIZE
+%endif
+%endif
 ;
 ; Stuff for the command line; we do some trickery here with equ to avoid
 ; tons of zeros appended to our file and wasting space

diff --git a/loadhigh.inc b/loadhigh.inc
index a8e8603..b7caec4 100644 (file)
--- a/loadhigh.inc
+++ b/loadhigh.inc
@@ -54,14 +54,11 @@ load_high:
                jna .size_ok
                mov eax,(1 << 16)
 .size_ok:
-               xor edx,edx
                push eax                        ; <B> Bytes transferred this chunk
-               div dword [ClustSize]           ; Convert to clusters
-               ; Round up...
-               add edx,byte -1                 ; Sets CF if EDX >= 1
-               adc eax,byte 0                  ; Add 1 to EAX if CF set
+               add eax,SECTOR_SIZE-1
+               shr eax,SECTOR_SHIFT            ; Convert to sectors
 
-               ; Now (e)ax contains the number of clusters to get
+               ; Now (e)ax contains the number of sectors to get
                push edi                        ; <C> Target buffer
                mov cx,ax
                xor bx,bx                       ; ES:0

diff --git a/pxelinux.asm b/pxelinux.asm
index 3070077..6ccab7d 100644 (file)
--- a/pxelinux.asm
+++ b/pxelinux.asm
@@ -52,6 +52,9 @@ TFTP_BLOCKSIZE_LG2 equ 9              ; log2(bytes/block)
 TFTP_BLOCKSIZE equ (1 << TFTP_BLOCKSIZE_LG2)
 %assign USE_PXE_PROVIDED_STACK 1       ; Use stack provided by PXE?
 
+SECTOR_SHIFT   equ TFTP_BLOCKSIZE_LG2
+SECTOR_SIZE    equ TFTP_BLOCKSIZE
+
 ;
 ; This is what we need to do when idle
 ;
@@ -246,14 +249,14 @@ RamdiskMax        resd 1                  ; Highest address for a ramdisk
 KernelSize     resd 1                  ; Size of kernel (bytes)
 SavedSSSP      resd 1                  ; Our SS:SP while running a COMBOOT image
 PMESP          resd 1                  ; Protected-mode ESP
+FSectors       resd 1                  ; Number of sectors in getc file
 InitStack      resd 1                  ; Pointer to reset stack
 RebootTime     resd 1                  ; Reboot timeout, if set by option
-KernelClust    resd 1                  ; Kernel size in clusters
+KernelSects    resd 1                  ; Kernel size in clusters
 StrucPtr       resd 1                  ; Pointer to PXENV+ or !PXE structure
 FBytes         equ $                   ; Used by open/getc
 FBytes1                resw 1
 FBytes2                resw 1
-FClust         resw 1                  ; Number of clusters in open/getc file
 FNextClust     resw 1                  ; Pointer to next cluster in d:o
 FPtr           resw 1                  ; Pointer to next char in buffer
 CmdOptPtr       resw 1                 ; Pointer to first option on cmd line
@@ -2536,9 +2539,6 @@ ServerPort        dw TFTP_PORT            ; TFTP server port
 ; Variables that are uninitialized in SYSLINUX but initialized here
 ;
                alignb 4, db 0
-ClustSize      dd TFTP_BLOCKSIZE       ; Bytes/cluster
-ClustPerMoby   dd 65536/TFTP_BLOCKSIZE ; Clusters per 64K
-SecPerClust    dw TFTP_BLOCKSIZE/512   ; Same as bsSecPerClust, but a word
 BufSafe                dw trackbufsize/TFTP_BLOCKSIZE  ; Clusters we can load into trackbuf
 BufSafeSec     dw trackbufsize/512     ; = how many sectors?
 BufSafeBytes   dw trackbufsize         ; = how many bytes?

diff --git a/runkernel.inc b/runkernel.inc
index 7728ccd..64dd463 100644 (file)
--- a/runkernel.inc
+++ b/runkernel.inc
@@ -64,12 +64,9 @@ kernel_sane: push ax
                shl edx,16                      ; register for the kernel size
                or eax,edx
                mov [KernelSize],eax
-               xor edx,edx
-               div dword [ClustSize]           ; # of clusters total
-               ; Round up...
-               add edx,byte -1                 ; Sets CF if EDX >= 1
-               adc eax,byte 0                  ; Add 1 to EAX if CF set
-                mov [KernelClust],eax
+               add eax,SECTOR_SIZE-1
+               shr eax,SECTOR_SHIFT
+                mov [KernelSects],eax          ; Total sectors in kernel
 
 ;
 ; Now, if we transfer these straight, we'll hit 64K boundaries.         Hence we
@@ -84,13 +81,12 @@ kernel_sane:        push ax
 ; If we have larger than 32K clusters, yes, we're hosed.
 ;
                call abort_check                ; Check for abort key
-               mov ecx,[ClustPerMoby]
-               shr ecx,1                       ; Half a moby
-               cmp ecx,[KernelClust]
+               mov ecx,8000h >> SECTOR_SHIFT   ; Half a moby (32K)
+               cmp ecx,[KernelSects]
                jna .normalkernel
-               mov ecx,[KernelClust]
+               mov ecx,[KernelSects]
 .normalkernel:
-               sub [KernelClust],ecx
+               sub [KernelSects],ecx
                xor bx,bx
                 pop si                          ; Cluster pointer on stack
                call getfssec