提交 1e97c75d 编写于 作者: M mengchao

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上级 3d0401f1
#
# if you want the ram-disk device, define this to be the
# size in blocks.
#
RAMDISK = #-DRAMDISK=512
AS86 =as86 -0 -a
LD86 =ld86 -0
AS =gas
LD =gld
LDFLAGS =-s -x -M
CC =gcc $(RAMDISK)
CFLAGS =-Wall -O -fstrength-reduce -fomit-frame-pointer \
-fcombine-regs -mstring-insns
CPP =cpp -nostdinc -Iinclude
#
# ROOT_DEV specifies the default root-device when making the image.
# This can be either FLOPPY, /dev/xxxx or empty, in which case the
# default of /dev/hd6 is used by 'build'.
#
ROOT_DEV=/dev/hd6
ARCHIVES=kernel/kernel.o mm/mm.o fs/fs.o
DRIVERS =kernel/blk_drv/blk_drv.a kernel/chr_drv/chr_drv.a
MATH =kernel/math/math.a
LIBS =lib/lib.a
.c.s:
$(CC) $(CFLAGS) \
-nostdinc -Iinclude -S -o $*.s $<
.s.o:
$(AS) -c -o $*.o $<
.c.o:
$(CC) $(CFLAGS) \
-nostdinc -Iinclude -c -o $*.o $<
all: Image
Image: boot/bootsect boot/setup tools/system tools/build
tools/build boot/bootsect boot/setup tools/system $(ROOT_DEV) > Image
sync
disk: Image
dd bs=8192 if=Image of=/dev/PS0
tools/build: tools/build.c
$(CC) $(CFLAGS) \
-o tools/build tools/build.c
boot/head.o: boot/head.s
tools/system: boot/head.o init/main.o \
$(ARCHIVES) $(DRIVERS) $(MATH) $(LIBS)
$(LD) $(LDFLAGS) boot/head.o init/main.o \
$(ARCHIVES) \
$(DRIVERS) \
$(MATH) \
$(LIBS) \
-o tools/system > System.map
kernel/math/math.a:
(cd kernel/math; make)
kernel/blk_drv/blk_drv.a:
(cd kernel/blk_drv; make)
kernel/chr_drv/chr_drv.a:
(cd kernel/chr_drv; make)
kernel/kernel.o:
(cd kernel; make)
mm/mm.o:
(cd mm; make)
fs/fs.o:
(cd fs; make)
lib/lib.a:
(cd lib; make)
boot/setup: boot/setup.s
$(AS86) -o boot/setup.o boot/setup.s
$(LD86) -s -o boot/setup boot/setup.o
boot/bootsect: boot/bootsect.s
$(AS86) -o boot/bootsect.o boot/bootsect.s
$(LD86) -s -o boot/bootsect boot/bootsect.o
tmp.s: boot/bootsect.s tools/system
(echo -n "SYSSIZE = (";ls -l tools/system | grep system \
| cut -c25-31 | tr '\012' ' '; echo "+ 15 ) / 16") > tmp.s
cat boot/bootsect.s >> tmp.s
clean:
rm -f Image System.map tmp_make core boot/bootsect boot/setup
rm -f init/*.o tools/system tools/build boot/*.o
(cd mm;make clean)
(cd fs;make clean)
(cd kernel;make clean)
(cd lib;make clean)
backup: clean
(cd .. ; tar cf - linux | compress - > backup.Z)
sync
dep:
sed '/\#\#\# Dependencies/q' < Makefile > tmp_make
(for i in init/*.c;do echo -n "init/";$(CPP) -M $$i;done) >> tmp_make
cp tmp_make Makefile
(cd fs; make dep)
(cd kernel; make dep)
(cd mm; make dep)
### Dependencies:
init/main.o : init/main.c include/unistd.h include/sys/stat.h \
include/sys/types.h include/sys/times.h include/sys/utsname.h \
include/utime.h include/time.h include/linux/tty.h include/termios.h \
include/linux/sched.h include/linux/head.h include/linux/fs.h \
include/linux/mm.h include/signal.h include/asm/system.h include/asm/io.h \
include/stddef.h include/stdarg.h include/fcntl.h
!
! SYS_SIZE is the number of clicks (16 bytes) to be loaded.
! 0x3000 is 0x30000 bytes = 196kB, more than enough for current
! versions of linux
!
SYSSIZE = 0x3000
!
! bootsect.s (C) 1991 Linus Torvalds
!
! bootsect.s is loaded at 0x7c00 by the bios-startup routines, and moves
! iself out of the way to address 0x90000, and jumps there.
!
! It then loads 'setup' directly after itself (0x90200), and the system
! at 0x10000, using BIOS interrupts.
!
! NOTE! currently system is at most 8*65536 bytes long. This should be no
! problem, even in the future. I want to keep it simple. This 512 kB
! kernel size should be enough, especially as this doesn't contain the
! buffer cache as in minix
!
! The loader has been made as simple as possible, and continuos
! read errors will result in a unbreakable loop. Reboot by hand. It
! loads pretty fast by getting whole sectors at a time whenever possible.
.globl begtext, begdata, begbss, endtext, enddata, endbss
.text
begtext:
.data
begdata:
.bss
begbss:
.text
SETUPLEN = 4 ! nr of setup-sectors
BOOTSEG = 0x07c0 ! original address of boot-sector
INITSEG = 0x9000 ! we move boot here - out of the way
SETUPSEG = 0x9020 ! setup starts here
SYSSEG = 0x1000 ! system loaded at 0x10000 (65536).
ENDSEG = SYSSEG + SYSSIZE ! where to stop loading
! ROOT_DEV: 0x000 - same type of floppy as boot.
! 0x301 - first partition on first drive etc
ROOT_DEV = 0x306
entry start
start:
mov ax,#BOOTSEG
mov ds,ax
mov ax,#INITSEG
mov es,ax
mov cx,#256
sub si,si
sub di,di
rep
movw
jmpi go,INITSEG
go: mov ax,cs
mov ds,ax
mov es,ax
! put stack at 0x9ff00.
mov ss,ax
mov sp,#0xFF00 ! arbitrary value >>512
! load the setup-sectors directly after the bootblock.
! Note that 'es' is already set up.
load_setup:
mov dx,#0x0000 ! drive 0, head 0
mov cx,#0x0002 ! sector 2, track 0
mov bx,#0x0200 ! address = 512, in INITSEG
mov ax,#0x0200+SETUPLEN ! service 2, nr of sectors
int 0x13 ! read it
jnc ok_load_setup ! ok - continue
mov dx,#0x0000
mov ax,#0x0000 ! reset the diskette
int 0x13
j load_setup
ok_load_setup:
! Get disk drive parameters, specifically nr of sectors/track
mov dl,#0x00
mov ax,#0x0800 ! AH=8 is get drive parameters
int 0x13
mov ch,#0x00
seg cs
mov sectors,cx
mov ax,#INITSEG
mov es,ax
! Print some inane message
mov ah,#0x03 ! read cursor pos
xor bh,bh
int 0x10
mov cx,#24
mov bx,#0x0007 ! page 0, attribute 7 (normal)
mov bp,#msg1
mov ax,#0x1301 ! write string, move cursor
int 0x10
! ok, we've written the message, now
! we want to load the system (at 0x10000)
mov ax,#SYSSEG
mov es,ax ! segment of 0x010000
call read_it
call kill_motor
! After that we check which root-device to use. If the device is
! defined (!= 0), nothing is done and the given device is used.
! Otherwise, either /dev/PS0 (2,28) or /dev/at0 (2,8), depending
! on the number of sectors that the BIOS reports currently.
seg cs
mov ax,root_dev
cmp ax,#0
jne root_defined
seg cs
mov bx,sectors
mov ax,#0x0208 ! /dev/ps0 - 1.2Mb
cmp bx,#15
je root_defined
mov ax,#0x021c ! /dev/PS0 - 1.44Mb
cmp bx,#18
je root_defined
undef_root:
jmp undef_root
root_defined:
seg cs
mov root_dev,ax
! after that (everyting loaded), we jump to
! the setup-routine loaded directly after
! the bootblock:
jmpi 0,SETUPSEG
! This routine loads the system at address 0x10000, making sure
! no 64kB boundaries are crossed. We try to load it as fast as
! possible, loading whole tracks whenever we can.
!
! in: es - starting address segment (normally 0x1000)
!
sread: .word 1+SETUPLEN ! sectors read of current track
head: .word 0 ! current head
track: .word 0 ! current track
read_it:
mov ax,es
test ax,#0x0fff
die: jne die ! es must be at 64kB boundary
xor bx,bx ! bx is starting address within segment
rp_read:
mov ax,es
cmp ax,#ENDSEG ! have we loaded all yet?
jb ok1_read
ret
ok1_read:
seg cs
mov ax,sectors
sub ax,sread
mov cx,ax
shl cx,#9
add cx,bx
jnc ok2_read
je ok2_read
xor ax,ax
sub ax,bx
shr ax,#9
ok2_read:
call read_track
mov cx,ax
add ax,sread
seg cs
cmp ax,sectors
jne ok3_read
mov ax,#1
sub ax,head
jne ok4_read
inc track
ok4_read:
mov head,ax
xor ax,ax
ok3_read:
mov sread,ax
shl cx,#9
add bx,cx
jnc rp_read
mov ax,es
add ax,#0x1000
mov es,ax
xor bx,bx
jmp rp_read
read_track:
push ax
push bx
push cx
push dx
mov dx,track
mov cx,sread
inc cx
mov ch,dl
mov dx,head
mov dh,dl
mov dl,#0
and dx,#0x0100
mov ah,#2
int 0x13
jc bad_rt
pop dx
pop cx
pop bx
pop ax
ret
bad_rt: mov ax,#0
mov dx,#0
int 0x13
pop dx
pop cx
pop bx
pop ax
jmp read_track
/*
* This procedure turns off the floppy drive motor, so
* that we enter the kernel in a known state, and
* don't have to worry about it later.
*/
kill_motor:
push dx
mov dx,#0x3f2
mov al,#0
outb
pop dx
ret
sectors:
.word 0
msg1:
.byte 13,10
.ascii "Loading system ..."
.byte 13,10,13,10
.org 508
root_dev:
.word ROOT_DEV
boot_flag:
.word 0xAA55
.text
endtext:
.data
enddata:
.bss
endbss:
/*
* linux/boot/head.s
*
* (C) 1991 Linus Torvalds
*/
/*
* head.s contains the 32-bit startup code.
*
* NOTE!!! Startup happens at absolute address 0x00000000, which is also where
* the page directory will exist. The startup code will be overwritten by
* the page directory.
*/
.text
.globl _idt,_gdt,_pg_dir,_tmp_floppy_area
_pg_dir:
startup_32:
movl $0x10,%eax
mov %ax,%ds
mov %ax,%es
mov %ax,%fs
mov %ax,%gs
lss _stack_start,%esp
call setup_idt
call setup_gdt
movl $0x10,%eax # reload all the segment registers
mov %ax,%ds # after changing gdt. CS was already
mov %ax,%es # reloaded in 'setup_gdt'
mov %ax,%fs
mov %ax,%gs
lss _stack_start,%esp
xorl %eax,%eax
1: incl %eax # check that A20 really IS enabled
movl %eax,0x000000 # loop forever if it isn't
cmpl %eax,0x100000
je 1b
/*
* NOTE! 486 should set bit 16, to check for write-protect in supervisor
* mode. Then it would be unnecessary with the "verify_area()"-calls.
* 486 users probably want to set the NE (#5) bit also, so as to use
* int 16 for math errors.
*/
movl %cr0,%eax # check math chip
andl $0x80000011,%eax # Save PG,PE,ET
/* "orl $0x10020,%eax" here for 486 might be good */
orl $2,%eax # set MP
movl %eax,%cr0
call check_x87
jmp after_page_tables
/*
* We depend on ET to be correct. This checks for 287/387.
*/
check_x87:
fninit
fstsw %ax
cmpb $0,%al
je 1f /* no coprocessor: have to set bits */
movl %cr0,%eax
xorl $6,%eax /* reset MP, set EM */
movl %eax,%cr0
ret
.align 2
1: .byte 0xDB,0xE4 /* fsetpm for 287, ignored by 387 */
ret
/*
* setup_idt
*
* sets up a idt with 256 entries pointing to
* ignore_int, interrupt gates. It then loads
* idt. Everything that wants to install itself
* in the idt-table may do so themselves. Interrupts
* are enabled elsewhere, when we can be relatively
* sure everything is ok. This routine will be over-
* written by the page tables.
*/
setup_idt:
lea ignore_int,%edx
movl $0x00080000,%eax
movw %dx,%ax /* selector = 0x0008 = cs */
movw $0x8E00,%dx /* interrupt gate - dpl=0, present */
lea _idt,%edi
mov $256,%ecx
rp_sidt:
movl %eax,(%edi)
movl %edx,4(%edi)
addl $8,%edi
dec %ecx
jne rp_sidt
lidt idt_descr
ret
/*
* setup_gdt
*
* This routines sets up a new gdt and loads it.
* Only two entries are currently built, the same
* ones that were built in init.s. The routine
* is VERY complicated at two whole lines, so this
* rather long comment is certainly needed :-).
* This routine will beoverwritten by the page tables.
*/
setup_gdt:
lgdt gdt_descr
ret
/*
* I put the kernel page tables right after the page directory,
* using 4 of them to span 16 Mb of physical memory. People with
* more than 16MB will have to expand this.
*/
.org 0x1000
pg0:
.org 0x2000
pg1:
.org 0x3000
pg2:
.org 0x4000
pg3:
.org 0x5000
/*
* tmp_floppy_area is used by the floppy-driver when DMA cannot
* reach to a buffer-block. It needs to be aligned, so that it isn't
* on a 64kB border.
*/
_tmp_floppy_area:
.fill 1024,1,0
after_page_tables:
pushl $0 # These are the parameters to main :-)
pushl $0
pushl $0
pushl $L6 # return address for main, if it decides to.
pushl $_main
jmp setup_paging
L6:
jmp L6 # main should never return here, but
# just in case, we know what happens.
/* This is the default interrupt "handler" :-) */
int_msg:
.asciz "Unknown interrupt\n\r"
.align 2
ignore_int:
pushl %eax
pushl %ecx
pushl %edx
push %ds
push %es
push %fs
movl $0x10,%eax
mov %ax,%ds
mov %ax,%es
mov %ax,%fs
pushl $int_msg
call _printk
popl %eax
pop %fs
pop %es
pop %ds
popl %edx
popl %ecx
popl %eax
iret
/*
* Setup_paging
*
* This routine sets up paging by setting the page bit
* in cr0. The page tables are set up, identity-mapping
* the first 16MB. The pager assumes that no illegal
* addresses are produced (ie >4Mb on a 4Mb machine).
*
* NOTE! Although all physical memory should be identity
* mapped by this routine, only the kernel page functions
* use the >1Mb addresses directly. All "normal" functions
* use just the lower 1Mb, or the local data space, which
* will be mapped to some other place - mm keeps track of
* that.
*
* For those with more memory than 16 Mb - tough luck. I've
* not got it, why should you :-) The source is here. Change
* it. (Seriously - it shouldn't be too difficult. Mostly
* change some constants etc. I left it at 16Mb, as my machine
* even cannot be extended past that (ok, but it was cheap :-)
* I've tried to show which constants to change by having
* some kind of marker at them (search for "16Mb"), but I
* won't guarantee that's all :-( )
*/
.align 2
setup_paging:
movl $1024*5,%ecx /* 5 pages - pg_dir+4 page tables */
xorl %eax,%eax
xorl %edi,%edi /* pg_dir is at 0x000 */
cld;rep;stosl
movl $pg0+7,_pg_dir /* set present bit/user r/w */
movl $pg1+7,_pg_dir+4 /* --------- " " --------- */
movl $pg2+7,_pg_dir+8 /* --------- " " --------- */
movl $pg3+7,_pg_dir+12 /* --------- " " --------- */
movl $pg3+4092,%edi
movl $0xfff007,%eax /* 16Mb - 4096 + 7 (r/w user,p) */
std
1: stosl /* fill pages backwards - more efficient :-) */
subl $0x1000,%eax
jge 1b
xorl %eax,%eax /* pg_dir is at 0x0000 */
movl %eax,%cr3 /* cr3 - page directory start */
movl %cr0,%eax
orl $0x80000000,%eax
movl %eax,%cr0 /* set paging (PG) bit */
ret /* this also flushes prefetch-queue */
.align 2
.word 0
idt_descr:
.word 256*8-1 # idt contains 256 entries
.long _idt
.align 2
.word 0
gdt_descr:
.word 256*8-1 # so does gdt (not that that's any
.long _gdt # magic number, but it works for me :^)
.align 3
_idt: .fill 256,8,0 # idt is uninitialized
_gdt: .quad 0x0000000000000000 /* NULL descriptor */
.quad 0x00c09a0000000fff /* 16Mb */
.quad 0x00c0920000000fff /* 16Mb */
.quad 0x0000000000000000 /* TEMPORARY - don't use */
.fill 252,8,0 /* space for LDT's and TSS's etc */
!
! setup.s (C) 1991 Linus Torvalds
!
! setup.s is responsible for getting the system data from the BIOS,
! and putting them into the appropriate places in system memory.
! both setup.s and system has been loaded by the bootblock.
!
! This code asks the bios for memory/disk/other parameters, and
! puts them in a "safe" place: 0x90000-0x901FF, ie where the
! boot-block used to be. It is then up to the protected mode
! system to read them from there before the area is overwritten
! for buffer-blocks.
!
! NOTE! These had better be the same as in bootsect.s!
INITSEG = 0x9000 ! we move boot here - out of the way
SYSSEG = 0x1000 ! system loaded at 0x10000 (65536).
SETUPSEG = 0x9020 ! this is the current segment
.globl begtext, begdata, begbss, endtext, enddata, endbss
.text
begtext:
.data
begdata:
.bss
begbss:
.text
entry start
start:
! ok, the read went well so we get current cursor position and save it for
! posterity.
mov ax,#INITSEG ! this is done in bootsect already, but...
mov ds,ax
mov ah,#0x03 ! read cursor pos
xor bh,bh
int 0x10 ! save it in known place, con_init fetches
mov [0],dx ! it from 0x90000.
! Get memory size (extended mem, kB)
mov ah,#0x88
int 0x15
mov [2],ax
! Get video-card data:
mov ah,#0x0f
int 0x10
mov [4],bx ! bh = display page
mov [6],ax ! al = video mode, ah = window width
! check for EGA/VGA and some config parameters
mov ah,#0x12
mov bl,#0x10
int 0x10
mov [8],ax
mov [10],bx
mov [12],cx
! Get hd0 data
mov ax,#0x0000
mov ds,ax
lds si,[4*0x41]
mov ax,#INITSEG
mov es,ax
mov di,#0x0080
mov cx,#0x10
rep
movsb
! Get hd1 data
mov ax,#0x0000
mov ds,ax
lds si,[4*0x46]
mov ax,#INITSEG
mov es,ax
mov di,#0x0090
mov cx,#0x10
rep
movsb
! Check that there IS a hd1 :-)
mov ax,#0x01500
mov dl,#0x81
int 0x13
jc no_disk1
cmp ah,#3
je is_disk1
no_disk1:
mov ax,#INITSEG
mov es,ax
mov di,#0x0090
mov cx,#0x10
mov ax,#0x00
rep
stosb
is_disk1:
! now we want to move to protected mode ...
cli ! no interrupts allowed !
! first we move the system to it's rightful place
mov ax,#0x0000
cld ! 'direction'=0, movs moves forward
do_move:
mov es,ax ! destination segment
add ax,#0x1000
cmp ax,#0x9000
jz end_move
mov ds,ax ! source segment
sub di,di
sub si,si
mov cx,#0x8000
rep
movsw
jmp do_move
! then we load the segment descriptors
end_move:
mov ax,#SETUPSEG ! right, forgot this at first. didn't work :-)
mov ds,ax
lidt idt_48 ! load idt with 0,0
lgdt gdt_48 ! load gdt with whatever appropriate
! that was painless, now we enable A20
call empty_8042
mov al,#0xD1 ! command write
out #0x64,al
call empty_8042
mov al,#0xDF ! A20 on
out #0x60,al
call empty_8042
! well, that went ok, I hope. Now we have to reprogram the interrupts :-(
! we put them right after the intel-reserved hardware interrupts, at
! int 0x20-0x2F. There they won't mess up anything. Sadly IBM really
! messed this up with the original PC, and they haven't been able to
! rectify it afterwards. Thus the bios puts interrupts at 0x08-0x0f,
! which is used for the internal hardware interrupts as well. We just
! have to reprogram the 8259's, and it isn't fun.
mov al,#0x11 ! initialization sequence
out #0x20,al ! send it to 8259A-1
.word 0x00eb,0x00eb ! jmp $+2, jmp $+2
out #0xA0,al ! and to 8259A-2
.word 0x00eb,0x00eb
mov al,#0x20 ! start of hardware int's (0x20)
out #0x21,al
.word 0x00eb,0x00eb
mov al,#0x28 ! start of hardware int's 2 (0x28)
out #0xA1,al
.word 0x00eb,0x00eb
mov al,#0x04 ! 8259-1 is master
out #0x21,al
.word 0x00eb,0x00eb
mov al,#0x02 ! 8259-2 is slave
out #0xA1,al
.word 0x00eb,0x00eb
mov al,#0x01 ! 8086 mode for both
out #0x21,al
.word 0x00eb,0x00eb
out #0xA1,al
.word 0x00eb,0x00eb
mov al,#0xFF ! mask off all interrupts for now
out #0x21,al
.word 0x00eb,0x00eb
out #0xA1,al
! well, that certainly wasn't fun :-(. Hopefully it works, and we don't
! need no steenking BIOS anyway (except for the initial loading :-).
! The BIOS-routine wants lots of unnecessary data, and it's less
! "interesting" anyway. This is how REAL programmers do it.
!
! Well, now's the time to actually move into protected mode. To make
! things as simple as possible, we do no register set-up or anything,
! we let the gnu-compiled 32-bit programs do that. We just jump to
! absolute address 0x00000, in 32-bit protected mode.
mov ax,#0x0001 ! protected mode (PE) bit
lmsw ax ! This is it!
jmpi 0,8 ! jmp offset 0 of segment 8 (cs)
! This routine checks that the keyboard command queue is empty
! No timeout is used - if this hangs there is something wrong with
! the machine, and we probably couldn't proceed anyway.
empty_8042:
.word 0x00eb,0x00eb
in al,#0x64 ! 8042 status port
test al,#2 ! is input buffer full?
jnz empty_8042 ! yes - loop
ret
gdt:
.word 0,0,0,0 ! dummy
.word 0x07FF ! 8Mb - limit=2047 (2048*4096=8Mb)
.word 0x0000 ! base address=0
.word 0x9A00 ! code read/exec
.word 0x00C0 ! granularity=4096, 386
.word 0x07FF ! 8Mb - limit=2047 (2048*4096=8Mb)
.word 0x0000 ! base address=0
.word 0x9200 ! data read/write
.word 0x00C0 ! granularity=4096, 386
idt_48:
.word 0 ! idt limit=0
.word 0,0 ! idt base=0L
gdt_48:
.word 0x800 ! gdt limit=2048, 256 GDT entries
.word 512+gdt,0x9 ! gdt base = 0X9xxxx
.text
endtext:
.data
enddata:
.bss
endbss:
AR =gar
AS =gas
CC =gcc
LD =gld
CFLAGS =-Wall -O -fstrength-reduce -fcombine-regs -fomit-frame-pointer \
-mstring-insns -nostdinc -I../include
CPP =gcc -E -nostdinc -I../include
.c.s:
$(CC) $(CFLAGS) \
-S -o $*.s $<
.c.o:
$(CC) $(CFLAGS) \
-c -o $*.o $<
.s.o:
$(AS) -o $*.o $<
OBJS= open.o read_write.o inode.o file_table.o buffer.o super.o \
block_dev.o char_dev.o file_dev.o stat.o exec.o pipe.o namei.o \
bitmap.o fcntl.o ioctl.o truncate.o
fs.o: $(OBJS)
$(LD) -r -o fs.o $(OBJS)
clean:
rm -f core *.o *.a tmp_make
for i in *.c;do rm -f `basename $$i .c`.s;done
dep:
sed '/\#\#\# Dependencies/q' < Makefile > tmp_make
(for i in *.c;do $(CPP) -M $$i;done) >> tmp_make
cp tmp_make Makefile
### Dependencies:
bitmap.o : bitmap.c ../include/string.h ../include/linux/sched.h \
../include/linux/head.h ../include/linux/fs.h ../include/sys/types.h \
../include/linux/mm.h ../include/signal.h ../include/linux/kernel.h
block_dev.o : block_dev.c ../include/errno.h ../include/linux/sched.h \
../include/linux/head.h ../include/linux/fs.h ../include/sys/types.h \
../include/linux/mm.h ../include/signal.h ../include/linux/kernel.h \
../include/asm/segment.h ../include/asm/system.h
buffer.o : buffer.c ../include/stdarg.h ../include/linux/config.h \
../include/linux/sched.h ../include/linux/head.h ../include/linux/fs.h \
../include/sys/types.h ../include/linux/mm.h ../include/signal.h \
../include/linux/kernel.h ../include/asm/system.h ../include/asm/io.h
char_dev.o : char_dev.c ../include/errno.h ../include/sys/types.h \
../include/linux/sched.h ../include/linux/head.h ../include/linux/fs.h \
../include/linux/mm.h ../include/signal.h ../include/linux/kernel.h \
../include/asm/segment.h ../include/asm/io.h
exec.o : exec.c ../include/errno.h ../include/string.h \
../include/sys/stat.h ../include/sys/types.h ../include/a.out.h \
../include/linux/fs.h ../include/linux/sched.h ../include/linux/head.h \
../include/linux/mm.h ../include/signal.h ../include/linux/kernel.h \
../include/asm/segment.h
fcntl.o : fcntl.c ../include/string.h ../include/errno.h \
../include/linux/sched.h ../include/linux/head.h ../include/linux/fs.h \
../include/sys/types.h ../include/linux/mm.h ../include/signal.h \
../include/linux/kernel.h ../include/asm/segment.h ../include/fcntl.h \
../include/sys/stat.h
file_dev.o : file_dev.c ../include/errno.h ../include/fcntl.h \
../include/sys/types.h ../include/linux/sched.h ../include/linux/head.h \
../include/linux/fs.h ../include/linux/mm.h ../include/signal.h \
../include/linux/kernel.h ../include/asm/segment.h
file_table.o : file_table.c ../include/linux/fs.h ../include/sys/types.h
inode.o : inode.c ../include/string.h ../include/sys/stat.h \
../include/sys/types.h ../include/linux/sched.h ../include/linux/head.h \
../include/linux/fs.h ../include/linux/mm.h ../include/signal.h \
../include/linux/kernel.h ../include/asm/system.h
ioctl.o : ioctl.c ../include/string.h ../include/errno.h \
../include/sys/stat.h ../include/sys/types.h ../include/linux/sched.h \
../include/linux/head.h ../include/linux/fs.h ../include/linux/mm.h \
../include/signal.h
namei.o : namei.c ../include/linux/sched.h ../include/linux/head.h \
../include/linux/fs.h ../include/sys/types.h ../include/linux/mm.h \
../include/signal.h ../include/linux/kernel.h ../include/asm/segment.h \
../include/string.h ../include/fcntl.h ../include/errno.h \
../include/const.h ../include/sys/stat.h
open.o : open.c ../include/string.h ../include/errno.h ../include/fcntl.h \
../include/sys/types.h ../include/utime.h ../include/sys/stat.h \
../include/linux/sched.h ../include/linux/head.h ../include/linux/fs.h \
../include/linux/mm.h ../include/signal.h ../include/linux/tty.h \
../include/termios.h ../include/linux/kernel.h ../include/asm/segment.h
pipe.o : pipe.c ../include/signal.h ../include/sys/types.h \
../include/linux/sched.h ../include/linux/head.h ../include/linux/fs.h \
../include/linux/mm.h ../include/asm/segment.h
read_write.o : read_write.c ../include/sys/stat.h ../include/sys/types.h \
../include/errno.h ../include/linux/kernel.h ../include/linux/sched.h \
../include/linux/head.h ../include/linux/fs.h ../include/linux/mm.h \
../include/signal.h ../include/asm/segment.h
stat.o : stat.c ../include/errno.h ../include/sys/stat.h \
../include/sys/types.h ../include/linux/fs.h ../include/linux/sched.h \
../include/linux/head.h ../include/linux/mm.h ../include/signal.h \
../include/linux/kernel.h ../include/asm/segment.h
super.o : super.c ../include/linux/config.h ../include/linux/sched.h \
../include/linux/head.h ../include/linux/fs.h ../include/sys/types.h \
../include/linux/mm.h ../include/signal.h ../include/linux/kernel.h \
../include/asm/system.h ../include/errno.h ../include/sys/stat.h
truncate.o : truncate.c ../include/linux/sched.h ../include/linux/head.h \
../include/linux/fs.h ../include/sys/types.h ../include/linux/mm.h \
../include/signal.h ../include/sys/stat.h
/*
* linux/fs/bitmap.c
*
* (C) 1991 Linus Torvalds
*/
/* bitmap.c contains the code that handles the inode and block bitmaps */
#include <string.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#define clear_block(addr) \
__asm__("cld\n\t" \
"rep\n\t" \
"stosl" \
::"a" (0),"c" (BLOCK_SIZE/4),"D" ((long) (addr)):"cx","di")
#define set_bit(nr,addr) ({\
register int res __asm__("ax"); \
__asm__ __volatile__("btsl %2,%3\n\tsetb %%al": \
"=a" (res):"0" (0),"r" (nr),"m" (*(addr))); \
res;})
#define clear_bit(nr,addr) ({\
register int res __asm__("ax"); \
__asm__ __volatile__("btrl %2,%3\n\tsetnb %%al": \
"=a" (res):"0" (0),"r" (nr),"m" (*(addr))); \
res;})
#define find_first_zero(addr) ({ \
int __res; \
__asm__("cld\n" \
"1:\tlodsl\n\t" \
"notl %%eax\n\t" \
"bsfl %%eax,%%edx\n\t" \
"je 2f\n\t" \
"addl %%edx,%%ecx\n\t" \
"jmp 3f\n" \
"2:\taddl $32,%%ecx\n\t" \
"cmpl $8192,%%ecx\n\t" \
"jl 1b\n" \
"3:" \
:"=c" (__res):"c" (0),"S" (addr):"ax","dx","si"); \
__res;})
void free_block(int dev, int block)
{
struct super_block * sb;
struct buffer_head * bh;
if (!(sb = get_super(dev)))
panic("trying to free block on nonexistent device");
if (block < sb->s_firstdatazone || block >= sb->s_nzones)
panic("trying to free block not in datazone");
bh = get_hash_table(dev,block);
if (bh) {
if (bh->b_count != 1) {
printk("trying to free block (%04x:%d), count=%d\n",
dev,block,bh->b_count);
return;
}
bh->b_dirt=0;
bh->b_uptodate=0;
brelse(bh);
}
block -= sb->s_firstdatazone - 1 ;
if (clear_bit(block&8191,sb->s_zmap[block/8192]->b_data)) {
printk("block (%04x:%d) ",dev,block+sb->s_firstdatazone-1);
panic("free_block: bit already cleared");
}
sb->s_zmap[block/8192]->b_dirt = 1;
}
int new_block(int dev)
{
struct buffer_head * bh;
struct super_block * sb;
int i,j;
if (!(sb = get_super(dev)))
panic("trying to get new block from nonexistant device");
j = 8192;
for (i=0 ; i<8 ; i++)
if (bh=sb->s_zmap[i])
if ((j=find_first_zero(bh->b_data))<8192)
break;
if (i>=8 || !bh || j>=8192)
return 0;
if (set_bit(j,bh->b_data))
panic("new_block: bit already set");
bh->b_dirt = 1;
j += i*8192 + sb->s_firstdatazone-1;
if (j >= sb->s_nzones)
return 0;
if (!(bh=getblk(dev,j)))
panic("new_block: cannot get block");
if (bh->b_count != 1)
panic("new block: count is != 1");
clear_block(bh->b_data);
bh->b_uptodate = 1;
bh->b_dirt = 1;
brelse(bh);
return j;
}
void free_inode(struct m_inode * inode)
{
struct super_block * sb;
struct buffer_head * bh;
if (!inode)
return;
if (!inode->i_dev) {
memset(inode,0,sizeof(*inode));
return;
}
if (inode->i_count>1) {
printk("trying to free inode with count=%d\n",inode->i_count);
panic("free_inode");
}
if (inode->i_nlinks)
panic("trying to free inode with links");
if (!(sb = get_super(inode->i_dev)))
panic("trying to free inode on nonexistent device");
if (inode->i_num < 1 || inode->i_num > sb->s_ninodes)
panic("trying to free inode 0 or nonexistant inode");
if (!(bh=sb->s_imap[inode->i_num>>13]))
panic("nonexistent imap in superblock");
if (clear_bit(inode->i_num&8191,bh->b_data))
printk("free_inode: bit already cleared.\n\r");
bh->b_dirt = 1;
memset(inode,0,sizeof(*inode));
}
struct m_inode * new_inode(int dev)
{
struct m_inode * inode;
struct super_block * sb;
struct buffer_head * bh;
int i,j;
if (!(inode=get_empty_inode()))
return NULL;
if (!(sb = get_super(dev)))
panic("new_inode with unknown device");
j = 8192;
for (i=0 ; i<8 ; i++)
if (bh=sb->s_imap[i])
if ((j=find_first_zero(bh->b_data))<8192)
break;
if (!bh || j >= 8192 || j+i*8192 > sb->s_ninodes) {
iput(inode);
return NULL;
}
if (set_bit(j,bh->b_data))
panic("new_inode: bit already set");
bh->b_dirt = 1;
inode->i_count=1;
inode->i_nlinks=1;
inode->i_dev=dev;
inode->i_uid=current->euid;
inode->i_gid=current->egid;
inode->i_dirt=1;
inode->i_num = j + i*8192;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
return inode;
}
/*
* linux/fs/block_dev.c
*
* (C) 1991 Linus Torvalds
*/
#include <errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <asm/segment.h>
#include <asm/system.h>
int block_write(int dev, long * pos, char * buf, int count)
{
int block = *pos >> BLOCK_SIZE_BITS;
int offset = *pos & (BLOCK_SIZE-1);
int chars;
int written = 0;
struct buffer_head * bh;
register char * p;
while (count>0) {
chars = BLOCK_SIZE - offset;
if (chars > count)
chars=count;
if (chars == BLOCK_SIZE)
bh = getblk(dev,block);
else
bh = breada(dev,block,block+1,block+2,-1);
block++;
if (!bh)
return written?written:-EIO;
p = offset + bh->b_data;
offset = 0;
*pos += chars;
written += chars;
count -= chars;
while (chars-->0)
*(p++) = get_fs_byte(buf++);
bh->b_dirt = 1;
brelse(bh);
}
return written;
}
int block_read(int dev, unsigned long * pos, char * buf, int count)
{
int block = *pos >> BLOCK_SIZE_BITS;
int offset = *pos & (BLOCK_SIZE-1);
int chars;
int read = 0;
struct buffer_head * bh;
register char * p;
while (count>0) {
chars = BLOCK_SIZE-offset;
if (chars > count)
chars = count;
if (!(bh = breada(dev,block,block+1,block+2,-1)))
return read?read:-EIO;
block++;
p = offset + bh->b_data;
offset = 0;
*pos += chars;
read += chars;
count -= chars;
while (chars-->0)
put_fs_byte(*(p++),buf++);
brelse(bh);
}
return read;
}
/*
* linux/fs/buffer.c
*
* (C) 1991 Linus Torvalds
*/
/*
* 'buffer.c' implements the buffer-cache functions. Race-conditions have
* been avoided by NEVER letting a interrupt change a buffer (except for the
* data, of course), but instead letting the caller do it. NOTE! As interrupts
* can wake up a caller, some cli-sti sequences are needed to check for
* sleep-on-calls. These should be extremely quick, though (I hope).
*/
/*
* NOTE! There is one discordant note here: checking floppies for
* disk change. This is where it fits best, I think, as it should
* invalidate changed floppy-disk-caches.
*/
#include <stdarg.h>
#include <linux/config.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <asm/system.h>
#include <asm/io.h>
extern int end;
struct buffer_head * start_buffer = (struct buffer_head *) &end;
struct buffer_head * hash_table[NR_HASH];
static struct buffer_head * free_list;
static struct task_struct * buffer_wait = NULL;
int NR_BUFFERS = 0;
static inline void wait_on_buffer(struct buffer_head * bh)
{
cli();
while (bh->b_lock)
sleep_on(&bh->b_wait);
sti();
}
int sys_sync(void)
{
int i;
struct buffer_head * bh;
sync_inodes(); /* write out inodes into buffers */
bh = start_buffer;
for (i=0 ; i<NR_BUFFERS ; i++,bh++) {
wait_on_buffer(bh);
if (bh->b_dirt)
ll_rw_block(WRITE,bh);
}
return 0;
}
int sync_dev(int dev)
{
int i;
struct buffer_head * bh;
bh = start_buffer;
for (i=0 ; i<NR_BUFFERS ; i++,bh++) {
if (bh->b_dev != dev)
continue;
wait_on_buffer(bh);
if (bh->b_dev == dev && bh->b_dirt)
ll_rw_block(WRITE,bh);
}
sync_inodes();
bh = start_buffer;
for (i=0 ; i<NR_BUFFERS ; i++,bh++) {
if (bh->b_dev != dev)
continue;
wait_on_buffer(bh);
if (bh->b_dev == dev && bh->b_dirt)
ll_rw_block(WRITE,bh);
}
return 0;
}
void inline invalidate_buffers(int dev)
{
int i;
struct buffer_head * bh;
bh = start_buffer;
for (i=0 ; i<NR_BUFFERS ; i++,bh++) {
if (bh->b_dev != dev)
continue;
wait_on_buffer(bh);
if (bh->b_dev == dev)
bh->b_uptodate = bh->b_dirt = 0;
}
}
/*
* This routine checks whether a floppy has been changed, and
* invalidates all buffer-cache-entries in that case. This
* is a relatively slow routine, so we have to try to minimize using
* it. Thus it is called only upon a 'mount' or 'open'. This
* is the best way of combining speed and utility, I think.
* People changing diskettes in the middle of an operation deserve
* to loose :-)
*
* NOTE! Although currently this is only for floppies, the idea is
* that any additional removable block-device will use this routine,
* and that mount/open needn't know that floppies/whatever are
* special.
*/
void check_disk_change(int dev)
{
int i;
if (MAJOR(dev) != 2)
return;
if (!floppy_change(dev & 0x03))
return;
for (i=0 ; i<NR_SUPER ; i++)
if (super_block[i].s_dev == dev)
put_super(super_block[i].s_dev);
invalidate_inodes(dev);
invalidate_buffers(dev);
}
#define _hashfn(dev,block) (((unsigned)(dev^block))%NR_HASH)
#define hash(dev,block) hash_table[_hashfn(dev,block)]
static inline void remove_from_queues(struct buffer_head * bh)
{
/* remove from hash-queue */
if (bh->b_next)
bh->b_next->b_prev = bh->b_prev;
if (bh->b_prev)
bh->b_prev->b_next = bh->b_next;
if (hash(bh->b_dev,bh->b_blocknr) == bh)
hash(bh->b_dev,bh->b_blocknr) = bh->b_next;
/* remove from free list */
if (!(bh->b_prev_free) || !(bh->b_next_free))
panic("Free block list corrupted");
bh->b_prev_free->b_next_free = bh->b_next_free;
bh->b_next_free->b_prev_free = bh->b_prev_free;
if (free_list == bh)
free_list = bh->b_next_free;
}
static inline void insert_into_queues(struct buffer_head * bh)
{
/* put at end of free list */
bh->b_next_free = free_list;
bh->b_prev_free = free_list->b_prev_free;
free_list->b_prev_free->b_next_free = bh;
free_list->b_prev_free = bh;
/* put the buffer in new hash-queue if it has a device */
bh->b_prev = NULL;
bh->b_next = NULL;
if (!bh->b_dev)
return;
bh->b_next = hash(bh->b_dev,bh->b_blocknr);
hash(bh->b_dev,bh->b_blocknr) = bh;
bh->b_next->b_prev = bh;
}
static struct buffer_head * find_buffer(int dev, int block)
{
struct buffer_head * tmp;
for (tmp = hash(dev,block) ; tmp != NULL ; tmp = tmp->b_next)
if (tmp->b_dev==dev && tmp->b_blocknr==block)
return tmp;
return NULL;
}
/*
* Why like this, I hear you say... The reason is race-conditions.
* As we don't lock buffers (unless we are readint them, that is),
* something might happen to it while we sleep (ie a read-error
* will force it bad). This shouldn't really happen currently, but
* the code is ready.
*/
struct buffer_head * get_hash_table(int dev, int block)
{
struct buffer_head * bh;
for (;;) {
if (!(bh=find_buffer(dev,block)))
return NULL;
bh->b_count++;
wait_on_buffer(bh);
if (bh->b_dev == dev && bh->b_blocknr == block)
return bh;
bh->b_count--;
}
}
/*
* Ok, this is getblk, and it isn't very clear, again to hinder
* race-conditions. Most of the code is seldom used, (ie repeating),
* so it should be much more efficient than it looks.
*
* The algoritm is changed: hopefully better, and an elusive bug removed.
*/
#define BADNESS(bh) (((bh)->b_dirt<<1)+(bh)->b_lock)
struct buffer_head * getblk(int dev,int block)
{
struct buffer_head * tmp, * bh;
repeat:
if (bh = get_hash_table(dev,block))
return bh;
tmp = free_list;
do {
if (tmp->b_count)
continue;
if (!bh || BADNESS(tmp)<BADNESS(bh)) {
bh = tmp;
if (!BADNESS(tmp))
break;
}
/* and repeat until we find something good */
} while ((tmp = tmp->b_next_free) != free_list);
if (!bh) {
sleep_on(&buffer_wait);
goto repeat;
}
wait_on_buffer(bh);
if (bh->b_count)
goto repeat;
while (bh->b_dirt) {
sync_dev(bh->b_dev);
wait_on_buffer(bh);
if (bh->b_count)
goto repeat;
}
/* NOTE!! While we slept waiting for this block, somebody else might */
/* already have added "this" block to the cache. check it */
if (find_buffer(dev,block))
goto repeat;
/* OK, FINALLY we know that this buffer is the only one of it's kind, */
/* and that it's unused (b_count=0), unlocked (b_lock=0), and clean */
bh->b_count=1;
bh->b_dirt=0;
bh->b_uptodate=0;
remove_from_queues(bh);
bh->b_dev=dev;
bh->b_blocknr=block;
insert_into_queues(bh);
return bh;
}
void brelse(struct buffer_head * buf)
{
if (!buf)
return;
wait_on_buffer(buf);
if (!(buf->b_count--))
panic("Trying to free free buffer");
wake_up(&buffer_wait);
}
/*
* bread() reads a specified block and returns the buffer that contains
* it. It returns NULL if the block was unreadable.
*/
struct buffer_head * bread(int dev,int block)
{
struct buffer_head * bh;
if (!(bh=getblk(dev,block)))
panic("bread: getblk returned NULL\n");
if (bh->b_uptodate)
return bh;
ll_rw_block(READ,bh);
wait_on_buffer(bh);
if (bh->b_uptodate)
return bh;
brelse(bh);
return NULL;
}
#define COPYBLK(from,to) \
__asm__("cld\n\t" \
"rep\n\t" \
"movsl\n\t" \
::"c" (BLOCK_SIZE/4),"S" (from),"D" (to) \
:"cx","di","si")
/*
* bread_page reads four buffers into memory at the desired address. It's
* a function of its own, as there is some speed to be got by reading them
* all at the same time, not waiting for one to be read, and then another
* etc.
*/
void bread_page(unsigned long address,int dev,int b[4])
{
struct buffer_head * bh[4];
int i;
for (i=0 ; i<4 ; i++)
if (b[i]) {
if (bh[i] = getblk(dev,b[i]))
if (!bh[i]->b_uptodate)
ll_rw_block(READ,bh[i]);
} else
bh[i] = NULL;
for (i=0 ; i<4 ; i++,address += BLOCK_SIZE)
if (bh[i]) {
wait_on_buffer(bh[i]);
if (bh[i]->b_uptodate)
COPYBLK((unsigned long) bh[i]->b_data,address);
brelse(bh[i]);
}
}
/*
* Ok, breada can be used as bread, but additionally to mark other
* blocks for reading as well. End the argument list with a negative
* number.
*/
struct buffer_head * breada(int dev,int first, ...)
{
va_list args;
struct buffer_head * bh, *tmp;
va_start(args,first);
if (!(bh=getblk(dev,first)))
panic("bread: getblk returned NULL\n");
if (!bh->b_uptodate)
ll_rw_block(READ,bh);
while ((first=va_arg(args,int))>=0) {
tmp=getblk(dev,first);
if (tmp) {
if (!tmp->b_uptodate)
ll_rw_block(READA,bh);
tmp->b_count--;
}
}
va_end(args);
wait_on_buffer(bh);
if (bh->b_uptodate)
return bh;
brelse(bh);
return (NULL);
}
void buffer_init(long buffer_end)
{
struct buffer_head * h = start_buffer;
void * b;
int i;
if (buffer_end == 1<<20)
b = (void *) (640*1024);
else
b = (void *) buffer_end;
while ( (b -= BLOCK_SIZE) >= ((void *) (h+1)) ) {
h->b_dev = 0;
h->b_dirt = 0;
h->b_count = 0;
h->b_lock = 0;
h->b_uptodate = 0;
h->b_wait = NULL;
h->b_next = NULL;
h->b_prev = NULL;
h->b_data = (char *) b;
h->b_prev_free = h-1;
h->b_next_free = h+1;
h++;
NR_BUFFERS++;
if (b == (void *) 0x100000)
b = (void *) 0xA0000;
}
h--;
free_list = start_buffer;
free_list->b_prev_free = h;
h->b_next_free = free_list;
for (i=0;i<NR_HASH;i++)
hash_table[i]=NULL;
}
/*
* linux/fs/char_dev.c
*
* (C) 1991 Linus Torvalds
*/
#include <errno.h>
#include <sys/types.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <asm/segment.h>
#include <asm/io.h>
extern int tty_read(unsigned minor,char * buf,int count);
extern int tty_write(unsigned minor,char * buf,int count);
typedef (*crw_ptr)(int rw,unsigned minor,char * buf,int count,off_t * pos);
static int rw_ttyx(int rw,unsigned minor,char * buf,int count,off_t * pos)
{
return ((rw==READ)?tty_read(minor,buf,count):
tty_write(minor,buf,count));
}
static int rw_tty(int rw,unsigned minor,char * buf,int count, off_t * pos)
{
if (current->tty<0)
return -EPERM;
return rw_ttyx(rw,current->tty,buf,count,pos);
}
static int rw_ram(int rw,char * buf, int count, off_t *pos)
{
return -EIO;
}
static int rw_mem(int rw,char * buf, int count, off_t * pos)
{
return -EIO;
}
static int rw_kmem(int rw,char * buf, int count, off_t * pos)
{
return -EIO;
}
static int rw_port(int rw,char * buf, int count, off_t * pos)
{
int i=*pos;
while (count-->0 && i<65536) {
if (rw==READ)
put_fs_byte(inb(i),buf++);
else
outb(get_fs_byte(buf++),i);
i++;
}
i -= *pos;
*pos += i;
return i;
}
static int rw_memory(int rw, unsigned minor, char * buf, int count, off_t * pos)
{
switch(minor) {
case 0:
return rw_ram(rw,buf,count,pos);
case 1:
return rw_mem(rw,buf,count,pos);
case 2:
return rw_kmem(rw,buf,count,pos);
case 3:
return (rw==READ)?0:count; /* rw_null */
case 4:
return rw_port(rw,buf,count,pos);
default:
return -EIO;
}
}
#define NRDEVS ((sizeof (crw_table))/(sizeof (crw_ptr)))
static crw_ptr crw_table[]={
NULL, /* nodev */
rw_memory, /* /dev/mem etc */
NULL, /* /dev/fd */
NULL, /* /dev/hd */
rw_ttyx, /* /dev/ttyx */
rw_tty, /* /dev/tty */
NULL, /* /dev/lp */
NULL}; /* unnamed pipes */
int rw_char(int rw,int dev, char * buf, int count, off_t * pos)
{
crw_ptr call_addr;
if (MAJOR(dev)>=NRDEVS)
return -ENODEV;
if (!(call_addr=crw_table[MAJOR(dev)]))
return -ENODEV;
return call_addr(rw,MINOR(dev),buf,count,pos);
}
/*
* linux/fs/exec.c
*
* (C) 1991 Linus Torvalds
*/
/*
* #!-checking implemented by tytso.
*/
/*
* Demand-loading implemented 01.12.91 - no need to read anything but
* the header into memory. The inode of the executable is put into
* "current->executable", and page faults do the actual loading. Clean.
*
* Once more I can proudly say that linux stood up to being changed: it
* was less than 2 hours work to get demand-loading completely implemented.
*/
#include <errno.h>
#include <string.h>
#include <sys/stat.h>
#include <a.out.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <asm/segment.h>
extern int sys_exit(int exit_code);
extern int sys_close(int fd);
/*
* MAX_ARG_PAGES defines the number of pages allocated for arguments
* and envelope for the new program. 32 should suffice, this gives
* a maximum env+arg of 128kB !
*/
#define MAX_ARG_PAGES 32
/*
* create_tables() parses the env- and arg-strings in new user
* memory and creates the pointer tables from them, and puts their
* addresses on the "stack", returning the new stack pointer value.
*/
static unsigned long * create_tables(char * p,int argc,int envc)
{
unsigned long *argv,*envp;
unsigned long * sp;
sp = (unsigned long *) (0xfffffffc & (unsigned long) p);
sp -= envc+1;
envp = sp;
sp -= argc+1;
argv = sp;
put_fs_long((unsigned long)envp,--sp);
put_fs_long((unsigned long)argv,--sp);
put_fs_long((unsigned long)argc,--sp);
while (argc-->0) {
put_fs_long((unsigned long) p,argv++);
while (get_fs_byte(p++)) /* nothing */ ;
}
put_fs_long(0,argv);
while (envc-->0) {
put_fs_long((unsigned long) p,envp++);
while (get_fs_byte(p++)) /* nothing */ ;
}
put_fs_long(0,envp);
return sp;
}
/*
* count() counts the number of arguments/envelopes
*/
static int count(char ** argv)
{
int i=0;
char ** tmp;
if (tmp = argv)
while (get_fs_long((unsigned long *) (tmp++)))
i++;
return i;
}
/*
* 'copy_string()' copies argument/envelope strings from user
* memory to free pages in kernel mem. These are in a format ready
* to be put directly into the top of new user memory.
*
* Modified by TYT, 11/24/91 to add the from_kmem argument, which specifies
* whether the string and the string array are from user or kernel segments:
*
* from_kmem argv * argv **
* 0 user space user space
* 1 kernel space user space
* 2 kernel space kernel space
*
* We do this by playing games with the fs segment register. Since it
* it is expensive to load a segment register, we try to avoid calling
* set_fs() unless we absolutely have to.
*/
static unsigned long copy_strings(int argc,char ** argv,unsigned long *page,
unsigned long p, int from_kmem)
{
char *tmp, *pag;
int len, offset = 0;
unsigned long old_fs, new_fs;
if (!p)
return 0; /* bullet-proofing */
new_fs = get_ds();
old_fs = get_fs();
if (from_kmem==2)
set_fs(new_fs);
while (argc-- > 0) {
if (from_kmem == 1)
set_fs(new_fs);
if (!(tmp = (char *)get_fs_long(((unsigned long *)argv)+argc)))
panic("argc is wrong");
if (from_kmem == 1)
set_fs(old_fs);
len=0; /* remember zero-padding */
do {
len++;
} while (get_fs_byte(tmp++));
if (p-len < 0) { /* this shouldn't happen - 128kB */
set_fs(old_fs);
return 0;
}
while (len) {
--p; --tmp; --len;
if (--offset < 0) {
offset = p % PAGE_SIZE;
if (from_kmem==2)
set_fs(old_fs);
if (!(pag = (char *) page[p/PAGE_SIZE]) &&
!(pag = (char *) page[p/PAGE_SIZE] =
(unsigned long *) get_free_page()))
return 0;
if (from_kmem==2)
set_fs(new_fs);
}
*(pag + offset) = get_fs_byte(tmp);
}
}
if (from_kmem==2)
set_fs(old_fs);
return p;
}
static unsigned long change_ldt(unsigned long text_size,unsigned long * page)
{
unsigned long code_limit,data_limit,code_base,data_base;
int i;
code_limit = text_size+PAGE_SIZE -1;
code_limit &= 0xFFFFF000;
data_limit = 0x4000000;
code_base = get_base(current->ldt[1]);
data_base = code_base;
set_base(current->ldt[1],code_base);
set_limit(current->ldt[1],code_limit);
set_base(current->ldt[2],data_base);
set_limit(current->ldt[2],data_limit);
/* make sure fs points to the NEW data segment */
__asm__("pushl $0x17\n\tpop %%fs"::);
data_base += data_limit;
for (i=MAX_ARG_PAGES-1 ; i>=0 ; i--) {
data_base -= PAGE_SIZE;
if (page[i])
put_page(page[i],data_base);
}
return data_limit;
}
/*
* 'do_execve()' executes a new program.
*/
int do_execve(unsigned long * eip,long tmp,char * filename,
char ** argv, char ** envp)
{
struct m_inode * inode;
struct buffer_head * bh;
struct exec ex;
unsigned long page[MAX_ARG_PAGES];
int i,argc,envc;
int e_uid, e_gid;
int retval;
int sh_bang = 0;
unsigned long p=PAGE_SIZE*MAX_ARG_PAGES-4;
if ((0xffff & eip[1]) != 0x000f)
panic("execve called from supervisor mode");
for (i=0 ; i<MAX_ARG_PAGES ; i++) /* clear page-table */
page[i]=0;
if (!(inode=namei(filename))) /* get executables inode */
return -ENOENT;
argc = count(argv);
envc = count(envp);
restart_interp:
if (!S_ISREG(inode->i_mode)) { /* must be regular file */
retval = -EACCES;
goto exec_error2;
}
i = inode->i_mode;
e_uid = (i & S_ISUID) ? inode->i_uid : current->euid;
e_gid = (i & S_ISGID) ? inode->i_gid : current->egid;
if (current->euid == inode->i_uid)
i >>= 6;
else if (current->egid == inode->i_gid)
i >>= 3;
if (!(i & 1) &&
!((inode->i_mode & 0111) && suser())) {
retval = -ENOEXEC;
goto exec_error2;
}
if (!(bh = bread(inode->i_dev,inode->i_zone[0]))) {
retval = -EACCES;
goto exec_error2;
}
ex = *((struct exec *) bh->b_data); /* read exec-header */
if ((bh->b_data[0] == '#') && (bh->b_data[1] == '!') && (!sh_bang)) {
/*
* This section does the #! interpretation.
* Sorta complicated, but hopefully it will work. -TYT
*/
char buf[1023], *cp, *interp, *i_name, *i_arg;
unsigned long old_fs;
strncpy(buf, bh->b_data+2, 1022);
brelse(bh);
iput(inode);
buf[1022] = '\0';
if (cp = strchr(buf, '\n')) {
*cp = '\0';
for (cp = buf; (*cp == ' ') || (*cp == '\t'); cp++);
}
if (!cp || *cp == '\0') {
retval = -ENOEXEC; /* No interpreter name found */
goto exec_error1;
}
interp = i_name = cp;
i_arg = 0;
for ( ; *cp && (*cp != ' ') && (*cp != '\t'); cp++) {
if (*cp == '/')
i_name = cp+1;
}
if (*cp) {
*cp++ = '\0';
i_arg = cp;
}
/*
* OK, we've parsed out the interpreter name and
* (optional) argument.
*/
if (sh_bang++ == 0) {
p = copy_strings(envc, envp, page, p, 0);
p = copy_strings(--argc, argv+1, page, p, 0);
}
/*
* Splice in (1) the interpreter's name for argv[0]
* (2) (optional) argument to interpreter
* (3) filename of shell script
*
* This is done in reverse order, because of how the
* user environment and arguments are stored.
*/
p = copy_strings(1, &filename, page, p, 1);
argc++;
if (i_arg) {
p = copy_strings(1, &i_arg, page, p, 2);
argc++;
}
p = copy_strings(1, &i_name, page, p, 2);
argc++;
if (!p) {
retval = -ENOMEM;
goto exec_error1;
}
/*
* OK, now restart the process with the interpreter's inode.
*/
old_fs = get_fs();
set_fs(get_ds());
if (!(inode=namei(interp))) { /* get executables inode */
set_fs(old_fs);
retval = -ENOENT;
goto exec_error1;
}
set_fs(old_fs);
goto restart_interp;
}
brelse(bh);
if (N_MAGIC(ex) != ZMAGIC || ex.a_trsize || ex.a_drsize ||
ex.a_text+ex.a_data+ex.a_bss>0x3000000 ||
inode->i_size < ex.a_text+ex.a_data+ex.a_syms+N_TXTOFF(ex)) {
retval = -ENOEXEC;
goto exec_error2;
}
if (N_TXTOFF(ex) != BLOCK_SIZE) {
printk("%s: N_TXTOFF != BLOCK_SIZE. See a.out.h.", filename);
retval = -ENOEXEC;
goto exec_error2;
}
if (!sh_bang) {
p = copy_strings(envc,envp,page,p,0);
p = copy_strings(argc,argv,page,p,0);
if (!p) {
retval = -ENOMEM;
goto exec_error2;
}
}
/* OK, This is the point of no return */
if (current->executable)
iput(current->executable);
current->executable = inode;
for (i=0 ; i<32 ; i++)
current->sigaction[i].sa_handler = NULL;
for (i=0 ; i<NR_OPEN ; i++)
if ((current->close_on_exec>>i)&1)
sys_close(i);
current->close_on_exec = 0;
free_page_tables(get_base(current->ldt[1]),get_limit(0x0f));
free_page_tables(get_base(current->ldt[2]),get_limit(0x17));
if (last_task_used_math == current)
last_task_used_math = NULL;
current->used_math = 0;
p += change_ldt(ex.a_text,page)-MAX_ARG_PAGES*PAGE_SIZE;
p = (unsigned long) create_tables((char *)p,argc,envc);
current->brk = ex.a_bss +
(current->end_data = ex.a_data +
(current->end_code = ex.a_text));
current->start_stack = p & 0xfffff000;
current->euid = e_uid;
current->egid = e_gid;
i = ex.a_text+ex.a_data;
while (i&0xfff)
put_fs_byte(0,(char *) (i++));
eip[0] = ex.a_entry; /* eip, magic happens :-) */
eip[3] = p; /* stack pointer */
return 0;
exec_error2:
iput(inode);
exec_error1:
for (i=0 ; i<MAX_ARG_PAGES ; i++)
free_page(page[i]);
return(retval);
}
/*
* linux/fs/fcntl.c
*
* (C) 1991 Linus Torvalds
*/
#include <string.h>
#include <errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <asm/segment.h>
#include <fcntl.h>
#include <sys/stat.h>
extern int sys_close(int fd);
static int dupfd(unsigned int fd, unsigned int arg)
{
if (fd >= NR_OPEN || !current->filp[fd])
return -EBADF;
if (arg >= NR_OPEN)
return -EINVAL;
while (arg < NR_OPEN)
if (current->filp[arg])
arg++;
else
break;
if (arg >= NR_OPEN)
return -EMFILE;
current->close_on_exec &= ~(1<<arg);
(current->filp[arg] = current->filp[fd])->f_count++;
return arg;
}
int sys_dup2(unsigned int oldfd, unsigned int newfd)
{
sys_close(newfd);
return dupfd(oldfd,newfd);
}
int sys_dup(unsigned int fildes)
{
return dupfd(fildes,0);
}
int sys_fcntl(unsigned int fd, unsigned int cmd, unsigned long arg)
{
struct file * filp;
if (fd >= NR_OPEN || !(filp = current->filp[fd]))
return -EBADF;
switch (cmd) {
case F_DUPFD:
return dupfd(fd,arg);
case F_GETFD:
return (current->close_on_exec>>fd)&1;
case F_SETFD:
if (arg&1)
current->close_on_exec |= (1<<fd);
else
current->close_on_exec &= ~(1<<fd);
return 0;
case F_GETFL:
return filp->f_flags;
case F_SETFL:
filp->f_flags &= ~(O_APPEND | O_NONBLOCK);
filp->f_flags |= arg & (O_APPEND | O_NONBLOCK);
return 0;
case F_GETLK: case F_SETLK: case F_SETLKW:
return -1;
default:
return -1;
}
}
/*
* linux/fs/file_dev.c
*
* (C) 1991 Linus Torvalds
*/
#include <errno.h>
#include <fcntl.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <asm/segment.h>
#define MIN(a,b) (((a)<(b))?(a):(b))
#define MAX(a,b) (((a)>(b))?(a):(b))
int file_read(struct m_inode * inode, struct file * filp, char * buf, int count)
{
int left,chars,nr;
struct buffer_head * bh;
if ((left=count)<=0)
return 0;
while (left) {
if (nr = bmap(inode,(filp->f_pos)/BLOCK_SIZE)) {
if (!(bh=bread(inode->i_dev,nr)))
break;
} else
bh = NULL;
nr = filp->f_pos % BLOCK_SIZE;
chars = MIN( BLOCK_SIZE-nr , left );
filp->f_pos += chars;
left -= chars;
if (bh) {
char * p = nr + bh->b_data;
while (chars-->0)
put_fs_byte(*(p++),buf++);
brelse(bh);
} else {
while (chars-->0)
put_fs_byte(0,buf++);
}
}
inode->i_atime = CURRENT_TIME;
return (count-left)?(count-left):-ERROR;
}
int file_write(struct m_inode * inode, struct file * filp, char * buf, int count)
{
off_t pos;
int block,c;
struct buffer_head * bh;
char * p;
int i=0;
/*
* ok, append may not work when many processes are writing at the same time
* but so what. That way leads to madness anyway.
*/
if (filp->f_flags & O_APPEND)
pos = inode->i_size;
else
pos = filp->f_pos;
while (i<count) {
if (!(block = create_block(inode,pos/BLOCK_SIZE)))
break;
if (!(bh=bread(inode->i_dev,block)))
break;
c = pos % BLOCK_SIZE;
p = c + bh->b_data;
bh->b_dirt = 1;
c = BLOCK_SIZE-c;
if (c > count-i) c = count-i;
pos += c;
if (pos > inode->i_size) {
inode->i_size = pos;
inode->i_dirt = 1;
}
i += c;
while (c-->0)
*(p++) = get_fs_byte(buf++);
brelse(bh);
}
inode->i_mtime = CURRENT_TIME;
if (!(filp->f_flags & O_APPEND)) {
filp->f_pos = pos;
inode->i_ctime = CURRENT_TIME;
}
return (i?i:-1);
}
/*
* linux/fs/file_table.c
*
* (C) 1991 Linus Torvalds
*/
#include <linux/fs.h>
struct file file_table[NR_FILE];
/*
* linux/fs/inode.c
*
* (C) 1991 Linus Torvalds
*/
#include <string.h>
#include <sys/stat.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <asm/system.h>
struct m_inode inode_table[NR_INODE]={{0,},};
static void read_inode(struct m_inode * inode);
static void write_inode(struct m_inode * inode);
static inline void wait_on_inode(struct m_inode * inode)
{
cli();
while (inode->i_lock)
sleep_on(&inode->i_wait);
sti();
}
static inline void lock_inode(struct m_inode * inode)
{
cli();
while (inode->i_lock)
sleep_on(&inode->i_wait);
inode->i_lock=1;
sti();
}
static inline void unlock_inode(struct m_inode * inode)
{
inode->i_lock=0;
wake_up(&inode->i_wait);
}
void invalidate_inodes(int dev)
{
int i;
struct m_inode * inode;
inode = 0+inode_table;
for(i=0 ; i<NR_INODE ; i++,inode++) {
wait_on_inode(inode);
if (inode->i_dev == dev) {
if (inode->i_count)
printk("inode in use on removed disk\n\r");
inode->i_dev = inode->i_dirt = 0;
}
}
}
void sync_inodes(void)
{
int i;
struct m_inode * inode;
inode = 0+inode_table;
for(i=0 ; i<NR_INODE ; i++,inode++) {
wait_on_inode(inode);
if (inode->i_dirt && !inode->i_pipe)
write_inode(inode);
}
}
static int _bmap(struct m_inode * inode,int block,int create)
{
struct buffer_head * bh;
int i;
if (block<0)
panic("_bmap: block<0");
if (block >= 7+512+512*512)
panic("_bmap: block>big");
if (block<7) {
if (create && !inode->i_zone[block])
if (inode->i_zone[block]=new_block(inode->i_dev)) {
inode->i_ctime=CURRENT_TIME;
inode->i_dirt=1;
}
return inode->i_zone[block];
}
block -= 7;
if (block<512) {
if (create && !inode->i_zone[7])
if (inode->i_zone[7]=new_block(inode->i_dev)) {
inode->i_dirt=1;
inode->i_ctime=CURRENT_TIME;
}
if (!inode->i_zone[7])
return 0;
if (!(bh = bread(inode->i_dev,inode->i_zone[7])))
return 0;
i = ((unsigned short *) (bh->b_data))[block];
if (create && !i)
if (i=new_block(inode->i_dev)) {
((unsigned short *) (bh->b_data))[block]=i;
bh->b_dirt=1;
}
brelse(bh);
return i;
}
block -= 512;
if (create && !inode->i_zone[8])
if (inode->i_zone[8]=new_block(inode->i_dev)) {
inode->i_dirt=1;
inode->i_ctime=CURRENT_TIME;
}
if (!inode->i_zone[8])
return 0;
if (!(bh=bread(inode->i_dev,inode->i_zone[8])))
return 0;
i = ((unsigned short *)bh->b_data)[block>>9];
if (create && !i)
if (i=new_block(inode->i_dev)) {
((unsigned short *) (bh->b_data))[block>>9]=i;
bh->b_dirt=1;
}
brelse(bh);
if (!i)
return 0;
if (!(bh=bread(inode->i_dev,i)))
return 0;
i = ((unsigned short *)bh->b_data)[block&511];
if (create && !i)
if (i=new_block(inode->i_dev)) {
((unsigned short *) (bh->b_data))[block&511]=i;
bh->b_dirt=1;
}
brelse(bh);
return i;
}
int bmap(struct m_inode * inode,int block)
{
return _bmap(inode,block,0);
}
int create_block(struct m_inode * inode, int block)
{
return _bmap(inode,block,1);
}
void iput(struct m_inode * inode)
{
if (!inode)
return;
wait_on_inode(inode);
if (!inode->i_count)
panic("iput: trying to free free inode");
if (inode->i_pipe) {
wake_up(&inode->i_wait);
if (--inode->i_count)
return;
free_page(inode->i_size);
inode->i_count=0;
inode->i_dirt=0;
inode->i_pipe=0;
return;
}
if (!inode->i_dev) {
inode->i_count--;
return;
}
if (S_ISBLK(inode->i_mode)) {
sync_dev(inode->i_zone[0]);
wait_on_inode(inode);
}
repeat:
if (inode->i_count>1) {
inode->i_count--;
return;
}
if (!inode->i_nlinks) {
truncate(inode);
free_inode(inode);
return;
}
if (inode->i_dirt) {
write_inode(inode); /* we can sleep - so do again */
wait_on_inode(inode);
goto repeat;
}
inode->i_count--;
return;
}
struct m_inode * get_empty_inode(void)
{
struct m_inode * inode;
static struct m_inode * last_inode = inode_table;
int i;
do {
inode = NULL;
for (i = NR_INODE; i ; i--) {
if (++last_inode >= inode_table + NR_INODE)
last_inode = inode_table;
if (!last_inode->i_count) {
inode = last_inode;
if (!inode->i_dirt && !inode->i_lock)
break;
}
}
if (!inode) {
for (i=0 ; i<NR_INODE ; i++)
printk("%04x: %6d\t",inode_table[i].i_dev,
inode_table[i].i_num);
panic("No free inodes in mem");
}
wait_on_inode(inode);
while (inode->i_dirt) {
write_inode(inode);
wait_on_inode(inode);
}
} while (inode->i_count);
memset(inode,0,sizeof(*inode));
inode->i_count = 1;
return inode;
}
struct m_inode * get_pipe_inode(void)
{
struct m_inode * inode;
if (!(inode = get_empty_inode()))
return NULL;
if (!(inode->i_size=get_free_page())) {
inode->i_count = 0;
return NULL;
}
inode->i_count = 2; /* sum of readers/writers */
PIPE_HEAD(*inode) = PIPE_TAIL(*inode) = 0;
inode->i_pipe = 1;
return inode;
}
struct m_inode * iget(int dev,int nr)
{
struct m_inode * inode, * empty;
if (!dev)
panic("iget with dev==0");
empty = get_empty_inode();
inode = inode_table;
while (inode < NR_INODE+inode_table) {
if (inode->i_dev != dev || inode->i_num != nr) {
inode++;
continue;
}
wait_on_inode(inode);
if (inode->i_dev != dev || inode->i_num != nr) {
inode = inode_table;
continue;
}
inode->i_count++;
if (inode->i_mount) {
int i;
for (i = 0 ; i<NR_SUPER ; i++)
if (super_block[i].s_imount==inode)
break;
if (i >= NR_SUPER) {
printk("Mounted inode hasn't got sb\n");
if (empty)
iput(empty);
return inode;
}
iput(inode);
dev = super_block[i].s_dev;
nr = ROOT_INO;
inode = inode_table;
continue;
}
if (empty)
iput(empty);
return inode;
}
if (!empty)
return (NULL);
inode=empty;
inode->i_dev = dev;
inode->i_num = nr;
read_inode(inode);
return inode;
}
static void read_inode(struct m_inode * inode)
{
struct super_block * sb;
struct buffer_head * bh;
int block;
lock_inode(inode);
if (!(sb=get_super(inode->i_dev)))
panic("trying to read inode without dev");
block = 2 + sb->s_imap_blocks + sb->s_zmap_blocks +
(inode->i_num-1)/INODES_PER_BLOCK;
if (!(bh=bread(inode->i_dev,block)))
panic("unable to read i-node block");
*(struct d_inode *)inode =
((struct d_inode *)bh->b_data)
[(inode->i_num-1)%INODES_PER_BLOCK];
brelse(bh);
unlock_inode(inode);
}
static void write_inode(struct m_inode * inode)
{
struct super_block * sb;
struct buffer_head * bh;
int block;
lock_inode(inode);
if (!inode->i_dirt || !inode->i_dev) {
unlock_inode(inode);
return;
}
if (!(sb=get_super(inode->i_dev)))
panic("trying to write inode without device");
block = 2 + sb->s_imap_blocks + sb->s_zmap_blocks +
(inode->i_num-1)/INODES_PER_BLOCK;
if (!(bh=bread(inode->i_dev,block)))
panic("unable to read i-node block");
((struct d_inode *)bh->b_data)
[(inode->i_num-1)%INODES_PER_BLOCK] =
*(struct d_inode *)inode;
bh->b_dirt=1;
inode->i_dirt=0;
brelse(bh);
unlock_inode(inode);
}
/*
* linux/fs/ioctl.c
*
* (C) 1991 Linus Torvalds
*/
#include <string.h>
#include <errno.h>
#include <sys/stat.h>
#include <linux/sched.h>
extern int tty_ioctl(int dev, int cmd, int arg);
typedef int (*ioctl_ptr)(int dev,int cmd,int arg);
#define NRDEVS ((sizeof (ioctl_table))/(sizeof (ioctl_ptr)))
static ioctl_ptr ioctl_table[]={
NULL, /* nodev */
NULL, /* /dev/mem */
NULL, /* /dev/fd */
NULL, /* /dev/hd */
tty_ioctl, /* /dev/ttyx */
tty_ioctl, /* /dev/tty */
NULL, /* /dev/lp */
NULL}; /* named pipes */
int sys_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
{
struct file * filp;
int dev,mode;
if (fd >= NR_OPEN || !(filp = current->filp[fd]))
return -EBADF;
mode=filp->f_inode->i_mode;
if (!S_ISCHR(mode) && !S_ISBLK(mode))
return -EINVAL;
dev = filp->f_inode->i_zone[0];
if (MAJOR(dev) >= NRDEVS)
return -ENODEV;
if (!ioctl_table[MAJOR(dev)])
return -ENOTTY;
return ioctl_table[MAJOR(dev)](dev,cmd,arg);
}
/*
* linux/fs/namei.c
*
* (C) 1991 Linus Torvalds
*/
/*
* Some corrections by tytso.
*/
#include <linux/sched.h>
#include <linux/kernel.h>
#include <asm/segment.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <const.h>
#include <sys/stat.h>
#define ACC_MODE(x) ("\004\002\006\377"[(x)&O_ACCMODE])
/*
* comment out this line if you want names > NAME_LEN chars to be
* truncated. Else they will be disallowed.
*/
/* #define NO_TRUNCATE */
#define MAY_EXEC 1
#define MAY_WRITE 2
#define MAY_READ 4
/*
* permission()
*
* is used to check for read/write/execute permissions on a file.
* I don't know if we should look at just the euid or both euid and
* uid, but that should be easily changed.
*/
static int permission(struct m_inode * inode,int mask)
{
int mode = inode->i_mode;
/* special case: not even root can read/write a deleted file */
if (inode->i_dev && !inode->i_nlinks)
return 0;
else if (current->euid==inode->i_uid)
mode >>= 6;
else if (current->egid==inode->i_gid)
mode >>= 3;
if (((mode & mask & 0007) == mask) || suser())
return 1;
return 0;
}
/*
* ok, we cannot use strncmp, as the name is not in our data space.
* Thus we'll have to use match. No big problem. Match also makes
* some sanity tests.
*
* NOTE! unlike strncmp, match returns 1 for success, 0 for failure.
*/
static int match(int len,const char * name,struct dir_entry * de)
{
register int same __asm__("ax");
if (!de || !de->inode || len > NAME_LEN)
return 0;
if (len < NAME_LEN && de->name[len])
return 0;
__asm__("cld\n\t"
"fs ; repe ; cmpsb\n\t"
"setz %%al"
:"=a" (same)
:"0" (0),"S" ((long) name),"D" ((long) de->name),"c" (len)
:"cx","di","si");
return same;
}
/*
* find_entry()
*
* finds an entry in the specified directory with the wanted name. It
* returns the cache buffer in which the entry was found, and the entry
* itself (as a parameter - res_dir). It does NOT read the inode of the
* entry - you'll have to do that yourself if you want to.
*
* This also takes care of the few special cases due to '..'-traversal
* over a pseudo-root and a mount point.
*/
static struct buffer_head * find_entry(struct m_inode ** dir,
const char * name, int namelen, struct dir_entry ** res_dir)
{
int entries;
int block,i;
struct buffer_head * bh;
struct dir_entry * de;
struct super_block * sb;
#ifdef NO_TRUNCATE
if (namelen > NAME_LEN)
return NULL;
#else
if (namelen > NAME_LEN)
namelen = NAME_LEN;
#endif
entries = (*dir)->i_size / (sizeof (struct dir_entry));
*res_dir = NULL;
if (!namelen)
return NULL;
/* check for '..', as we might have to do some "magic" for it */
if (namelen==2 && get_fs_byte(name)=='.' && get_fs_byte(name+1)=='.') {
/* '..' in a pseudo-root results in a faked '.' (just change namelen) */
if ((*dir) == current->root)
namelen=1;
else if ((*dir)->i_num == ROOT_INO) {
/* '..' over a mount-point results in 'dir' being exchanged for the mounted
directory-inode. NOTE! We set mounted, so that we can iput the new dir */
sb=get_super((*dir)->i_dev);
if (sb->s_imount) {
iput(*dir);
(*dir)=sb->s_imount;
(*dir)->i_count++;
}
}
}
if (!(block = (*dir)->i_zone[0]))
return NULL;
if (!(bh = bread((*dir)->i_dev,block)))
return NULL;
i = 0;
de = (struct dir_entry *) bh->b_data;
while (i < entries) {
if ((char *)de >= BLOCK_SIZE+bh->b_data) {
brelse(bh);
bh = NULL;
if (!(block = bmap(*dir,i/DIR_ENTRIES_PER_BLOCK)) ||
!(bh = bread((*dir)->i_dev,block))) {
i += DIR_ENTRIES_PER_BLOCK;
continue;
}
de = (struct dir_entry *) bh->b_data;
}
if (match(namelen,name,de)) {
*res_dir = de;
return bh;
}
de++;
i++;
}
brelse(bh);
return NULL;
}
/*
* add_entry()
*
* adds a file entry to the specified directory, using the same
* semantics as find_entry(). It returns NULL if it failed.
*
* NOTE!! The inode part of 'de' is left at 0 - which means you
* may not sleep between calling this and putting something into
* the entry, as someone else might have used it while you slept.
*/
static struct buffer_head * add_entry(struct m_inode * dir,
const char * name, int namelen, struct dir_entry ** res_dir)
{
int block,i;
struct buffer_head * bh;
struct dir_entry * de;
*res_dir = NULL;
#ifdef NO_TRUNCATE
if (namelen > NAME_LEN)
return NULL;
#else
if (namelen > NAME_LEN)
namelen = NAME_LEN;
#endif
if (!namelen)
return NULL;
if (!(block = dir->i_zone[0]))
return NULL;
if (!(bh = bread(dir->i_dev,block)))
return NULL;
i = 0;
de = (struct dir_entry *) bh->b_data;
while (1) {
if ((char *)de >= BLOCK_SIZE+bh->b_data) {
brelse(bh);
bh = NULL;
block = create_block(dir,i/DIR_ENTRIES_PER_BLOCK);
if (!block)
return NULL;
if (!(bh = bread(dir->i_dev,block))) {
i += DIR_ENTRIES_PER_BLOCK;
continue;
}
de = (struct dir_entry *) bh->b_data;
}
if (i*sizeof(struct dir_entry) >= dir->i_size) {
de->inode=0;
dir->i_size = (i+1)*sizeof(struct dir_entry);
dir->i_dirt = 1;
dir->i_ctime = CURRENT_TIME;
}
if (!de->inode) {
dir->i_mtime = CURRENT_TIME;
for (i=0; i < NAME_LEN ; i++)
de->name[i]=(i<namelen)?get_fs_byte(name+i):0;
bh->b_dirt = 1;
*res_dir = de;
return bh;
}
de++;
i++;
}
brelse(bh);
return NULL;
}
/*
* get_dir()
*
* Getdir traverses the pathname until it hits the topmost directory.
* It returns NULL on failure.
*/
static struct m_inode * get_dir(const char * pathname)
{
char c;
const char * thisname;
struct m_inode * inode;
struct buffer_head * bh;
int namelen,inr,idev;
struct dir_entry * de;
if (!current->root || !current->root->i_count)
panic("No root inode");
if (!current->pwd || !current->pwd->i_count)
panic("No cwd inode");
if ((c=get_fs_byte(pathname))=='/') {
inode = current->root;
pathname++;
} else if (c)
inode = current->pwd;
else
return NULL; /* empty name is bad */
inode->i_count++;
while (1) {
thisname = pathname;
if (!S_ISDIR(inode->i_mode) || !permission(inode,MAY_EXEC)) {
iput(inode);
return NULL;
}
for(namelen=0;(c=get_fs_byte(pathname++))&&(c!='/');namelen++)
/* nothing */ ;
if (!c)
return inode;
if (!(bh = find_entry(&inode,thisname,namelen,&de))) {
iput(inode);
return NULL;
}
inr = de->inode;
idev = inode->i_dev;
brelse(bh);
iput(inode);
if (!(inode = iget(idev,inr)))
return NULL;
}
}
/*
* dir_namei()
*
* dir_namei() returns the inode of the directory of the
* specified name, and the name within that directory.
*/
static struct m_inode * dir_namei(const char * pathname,
int * namelen, const char ** name)
{
char c;
const char * basename;
struct m_inode * dir;
if (!(dir = get_dir(pathname)))
return NULL;
basename = pathname;
while (c=get_fs_byte(pathname++))
if (c=='/')
basename=pathname;
*namelen = pathname-basename-1;
*name = basename;
return dir;
}
/*
* namei()
*
* is used by most simple commands to get the inode of a specified name.
* Open, link etc use their own routines, but this is enough for things
* like 'chmod' etc.
*/
struct m_inode * namei(const char * pathname)
{
const char * basename;
int inr,dev,namelen;
struct m_inode * dir;
struct buffer_head * bh;
struct dir_entry * de;
if (!(dir = dir_namei(pathname,&namelen,&basename)))
return NULL;
if (!namelen) /* special case: '/usr/' etc */
return dir;
bh = find_entry(&dir,basename,namelen,&de);
if (!bh) {
iput(dir);
return NULL;
}
inr = de->inode;
dev = dir->i_dev;
brelse(bh);
iput(dir);
dir=iget(dev,inr);
if (dir) {
dir->i_atime=CURRENT_TIME;
dir->i_dirt=1;
}
return dir;
}
/*
* open_namei()
*
* namei for open - this is in fact almost the whole open-routine.
*/
int open_namei(const char * pathname, int flag, int mode,
struct m_inode ** res_inode)
{
const char * basename;
int inr,dev,namelen;
struct m_inode * dir, *inode;
struct buffer_head * bh;
struct dir_entry * de;
if ((flag & O_TRUNC) && !(flag & O_ACCMODE))
flag |= O_WRONLY;
mode &= 0777 & ~current->umask;
mode |= I_REGULAR;
if (!(dir = dir_namei(pathname,&namelen,&basename)))
return -ENOENT;
if (!namelen) { /* special case: '/usr/' etc */
if (!(flag & (O_ACCMODE|O_CREAT|O_TRUNC))) {
*res_inode=dir;
return 0;
}
iput(dir);
return -EISDIR;
}
bh = find_entry(&dir,basename,namelen,&de);
if (!bh) {
if (!(flag & O_CREAT)) {
iput(dir);
return -ENOENT;
}
if (!permission(dir,MAY_WRITE)) {
iput(dir);
return -EACCES;
}
inode = new_inode(dir->i_dev);
if (!inode) {
iput(dir);
return -ENOSPC;
}
inode->i_uid = current->euid;
inode->i_mode = mode;
inode->i_dirt = 1;
bh = add_entry(dir,basename,namelen,&de);
if (!bh) {
inode->i_nlinks--;
iput(inode);
iput(dir);
return -ENOSPC;
}
de->inode = inode->i_num;
bh->b_dirt = 1;
brelse(bh);
iput(dir);
*res_inode = inode;
return 0;
}
inr = de->inode;
dev = dir->i_dev;
brelse(bh);
iput(dir);
if (flag & O_EXCL)
return -EEXIST;
if (!(inode=iget(dev,inr)))
return -EACCES;
if ((S_ISDIR(inode->i_mode) && (flag & O_ACCMODE)) ||
!permission(inode,ACC_MODE(flag))) {
iput(inode);
return -EPERM;
}
inode->i_atime = CURRENT_TIME;
if (flag & O_TRUNC)
truncate(inode);
*res_inode = inode;
return 0;
}
int sys_mknod(const char * filename, int mode, int dev)
{
const char * basename;
int namelen;
struct m_inode * dir, * inode;
struct buffer_head * bh;
struct dir_entry * de;
if (!suser())
return -EPERM;
if (!(dir = dir_namei(filename,&namelen,&basename)))
return -ENOENT;
if (!namelen) {
iput(dir);
return -ENOENT;
}
if (!permission(dir,MAY_WRITE)) {
iput(dir);
return -EPERM;
}
bh = find_entry(&dir,basename,namelen,&de);
if (bh) {
brelse(bh);
iput(dir);
return -EEXIST;
}
inode = new_inode(dir->i_dev);
if (!inode) {
iput(dir);
return -ENOSPC;
}
inode->i_mode = mode;
if (S_ISBLK(mode) || S_ISCHR(mode))
inode->i_zone[0] = dev;
inode->i_mtime = inode->i_atime = CURRENT_TIME;
inode->i_dirt = 1;
bh = add_entry(dir,basename,namelen,&de);
if (!bh) {
iput(dir);
inode->i_nlinks=0;
iput(inode);
return -ENOSPC;
}
de->inode = inode->i_num;
bh->b_dirt = 1;
iput(dir);
iput(inode);
brelse(bh);
return 0;
}
int sys_mkdir(const char * pathname, int mode)
{
const char * basename;
int namelen;
struct m_inode * dir, * inode;
struct buffer_head * bh, *dir_block;
struct dir_entry * de;
if (!suser())
return -EPERM;
if (!(dir = dir_namei(pathname,&namelen,&basename)))
return -ENOENT;
if (!namelen) {
iput(dir);
return -ENOENT;
}
if (!permission(dir,MAY_WRITE)) {
iput(dir);
return -EPERM;
}
bh = find_entry(&dir,basename,namelen,&de);
if (bh) {
brelse(bh);
iput(dir);
return -EEXIST;
}
inode = new_inode(dir->i_dev);
if (!inode) {
iput(dir);
return -ENOSPC;
}
inode->i_size = 32;
inode->i_dirt = 1;
inode->i_mtime = inode->i_atime = CURRENT_TIME;
if (!(inode->i_zone[0]=new_block(inode->i_dev))) {
iput(dir);
inode->i_nlinks--;
iput(inode);
return -ENOSPC;
}
inode->i_dirt = 1;
if (!(dir_block=bread(inode->i_dev,inode->i_zone[0]))) {
iput(dir);
free_block(inode->i_dev,inode->i_zone[0]);
inode->i_nlinks--;
iput(inode);
return -ERROR;
}
de = (struct dir_entry *) dir_block->b_data;
de->inode=inode->i_num;
strcpy(de->name,".");
de++;
de->inode = dir->i_num;
strcpy(de->name,"..");
inode->i_nlinks = 2;
dir_block->b_dirt = 1;
brelse(dir_block);
inode->i_mode = I_DIRECTORY | (mode & 0777 & ~current->umask);
inode->i_dirt = 1;
bh = add_entry(dir,basename,namelen,&de);
if (!bh) {
iput(dir);
free_block(inode->i_dev,inode->i_zone[0]);
inode->i_nlinks=0;
iput(inode);
return -ENOSPC;
}
de->inode = inode->i_num;
bh->b_dirt = 1;
dir->i_nlinks++;
dir->i_dirt = 1;
iput(dir);
iput(inode);
brelse(bh);
return 0;
}
/*
* routine to check that the specified directory is empty (for rmdir)
*/
static int empty_dir(struct m_inode * inode)
{
int nr,block;
int len;
struct buffer_head * bh;
struct dir_entry * de;
len = inode->i_size / sizeof (struct dir_entry);
if (len<2 || !inode->i_zone[0] ||
!(bh=bread(inode->i_dev,inode->i_zone[0]))) {
printk("warning - bad directory on dev %04x\n",inode->i_dev);
return 0;
}
de = (struct dir_entry *) bh->b_data;
if (de[0].inode != inode->i_num || !de[1].inode ||
strcmp(".",de[0].name) || strcmp("..",de[1].name)) {
printk("warning - bad directory on dev %04x\n",inode->i_dev);
return 0;
}
nr = 2;
de += 2;
while (nr<len) {
if ((void *) de >= (void *) (bh->b_data+BLOCK_SIZE)) {
brelse(bh);
block=bmap(inode,nr/DIR_ENTRIES_PER_BLOCK);
if (!block) {
nr += DIR_ENTRIES_PER_BLOCK;
continue;
}
if (!(bh=bread(inode->i_dev,block)))
return 0;
de = (struct dir_entry *) bh->b_data;
}
if (de->inode) {
brelse(bh);
return 0;
}
de++;
nr++;
}
brelse(bh);
return 1;
}
int sys_rmdir(const char * name)
{
const char * basename;
int namelen;
struct m_inode * dir, * inode;
struct buffer_head * bh;
struct dir_entry * de;
if (!suser())
return -EPERM;
if (!(dir = dir_namei(name,&namelen,&basename)))
return -ENOENT;
if (!namelen) {
iput(dir);
return -ENOENT;
}
if (!permission(dir,MAY_WRITE)) {
iput(dir);
return -EPERM;
}
bh = find_entry(&dir,basename,namelen,&de);
if (!bh) {
iput(dir);
return -ENOENT;
}
if (!(inode = iget(dir->i_dev, de->inode))) {
iput(dir);
brelse(bh);
return -EPERM;
}
if ((dir->i_mode & S_ISVTX) && current->euid &&
inode->i_uid != current->euid) {
iput(dir);
iput(inode);
brelse(bh);
return -EPERM;
}
if (inode->i_dev != dir->i_dev || inode->i_count>1) {
iput(dir);
iput(inode);
brelse(bh);
return -EPERM;
}
if (inode == dir) { /* we may not delete ".", but "../dir" is ok */
iput(inode);
iput(dir);
brelse(bh);
return -EPERM;
}
if (!S_ISDIR(inode->i_mode)) {
iput(inode);
iput(dir);
brelse(bh);
return -ENOTDIR;
}
if (!empty_dir(inode)) {
iput(inode);
iput(dir);
brelse(bh);
return -ENOTEMPTY;
}
if (inode->i_nlinks != 2)
printk("empty directory has nlink!=2 (%d)",inode->i_nlinks);
de->inode = 0;
bh->b_dirt = 1;
brelse(bh);
inode->i_nlinks=0;
inode->i_dirt=1;
dir->i_nlinks--;
dir->i_ctime = dir->i_mtime = CURRENT_TIME;
dir->i_dirt=1;
iput(dir);
iput(inode);
return 0;
}
int sys_unlink(const char * name)
{
const char * basename;
int namelen;
struct m_inode * dir, * inode;
struct buffer_head * bh;
struct dir_entry * de;
if (!(dir = dir_namei(name,&namelen,&basename)))
return -ENOENT;
if (!namelen) {
iput(dir);
return -ENOENT;
}
if (!permission(dir,MAY_WRITE)) {
iput(dir);
return -EPERM;
}
bh = find_entry(&dir,basename,namelen,&de);
if (!bh) {
iput(dir);
return -ENOENT;
}
if (!(inode = iget(dir->i_dev, de->inode))) {
iput(dir);
brelse(bh);
return -ENOENT;
}
if ((dir->i_mode & S_ISVTX) && !suser() &&
current->euid != inode->i_uid &&
current->euid != dir->i_uid) {
iput(dir);
iput(inode);
brelse(bh);
return -EPERM;
}
if (S_ISDIR(inode->i_mode)) {
iput(inode);
iput(dir);
brelse(bh);
return -EPERM;
}
if (!inode->i_nlinks) {
printk("Deleting nonexistent file (%04x:%d), %d\n",
inode->i_dev,inode->i_num,inode->i_nlinks);
inode->i_nlinks=1;
}
de->inode = 0;
bh->b_dirt = 1;
brelse(bh);
inode->i_nlinks--;
inode->i_dirt = 1;
inode->i_ctime = CURRENT_TIME;
iput(inode);
iput(dir);
return 0;
}
int sys_link(const char * oldname, const char * newname)
{
struct dir_entry * de;
struct m_inode * oldinode, * dir;
struct buffer_head * bh;
const char * basename;
int namelen;
oldinode=namei(oldname);
if (!oldinode)
return -ENOENT;
if (S_ISDIR(oldinode->i_mode)) {
iput(oldinode);
return -EPERM;
}
dir = dir_namei(newname,&namelen,&basename);
if (!dir) {
iput(oldinode);
return -EACCES;
}
if (!namelen) {
iput(oldinode);
iput(dir);
return -EPERM;
}
if (dir->i_dev != oldinode->i_dev) {
iput(dir);
iput(oldinode);
return -EXDEV;
}
if (!permission(dir,MAY_WRITE)) {
iput(dir);
iput(oldinode);
return -EACCES;
}
bh = find_entry(&dir,basename,namelen,&de);
if (bh) {
brelse(bh);
iput(dir);
iput(oldinode);
return -EEXIST;
}
bh = add_entry(dir,basename,namelen,&de);
if (!bh) {
iput(dir);
iput(oldinode);
return -ENOSPC;
}
de->inode = oldinode->i_num;
bh->b_dirt = 1;
brelse(bh);
iput(dir);
oldinode->i_nlinks++;
oldinode->i_ctime = CURRENT_TIME;
oldinode->i_dirt = 1;
iput(oldinode);
return 0;
}
/*
* linux/fs/open.c
*
* (C) 1991 Linus Torvalds
*/
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/types.h>
#include <utime.h>
#include <sys/stat.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/kernel.h>
#include <asm/segment.h>
int sys_ustat(int dev, struct ustat * ubuf)
{
return -ENOSYS;
}
int sys_utime(char * filename, struct utimbuf * times)
{
struct m_inode * inode;
long actime,modtime;
if (!(inode=namei(filename)))
return -ENOENT;
if (times) {
actime = get_fs_long((unsigned long *) &times->actime);
modtime = get_fs_long((unsigned long *) &times->modtime);
} else
actime = modtime = CURRENT_TIME;
inode->i_atime = actime;
inode->i_mtime = modtime;
inode->i_dirt = 1;
iput(inode);
return 0;
}
/*
* XXX should we use the real or effective uid? BSD uses the real uid,
* so as to make this call useful to setuid programs.
*/
int sys_access(const char * filename,int mode)
{
struct m_inode * inode;
int res, i_mode;
mode &= 0007;
if (!(inode=namei(filename)))
return -EACCES;
i_mode = res = inode->i_mode & 0777;
iput(inode);
if (current->uid == inode->i_uid)
res >>= 6;
else if (current->gid == inode->i_gid)
res >>= 6;
if ((res & 0007 & mode) == mode)
return 0;
/*
* XXX we are doing this test last because we really should be
* swapping the effective with the real user id (temporarily),
* and then calling suser() routine. If we do call the
* suser() routine, it needs to be called last.
*/
if ((!current->uid) &&
(!(mode & 1) || (i_mode & 0111)))
return 0;
return -EACCES;
}
int sys_chdir(const char * filename)
{
struct m_inode * inode;
if (!(inode = namei(filename)))
return -ENOENT;
if (!S_ISDIR(inode->i_mode)) {
iput(inode);
return -ENOTDIR;
}
iput(current->pwd);
current->pwd = inode;
return (0);
}
int sys_chroot(const char * filename)
{
struct m_inode * inode;
if (!(inode=namei(filename)))
return -ENOENT;
if (!S_ISDIR(inode->i_mode)) {
iput(inode);
return -ENOTDIR;
}
iput(current->root);
current->root = inode;
return (0);
}
int sys_chmod(const char * filename,int mode)
{
struct m_inode * inode;
if (!(inode=namei(filename)))
return -ENOENT;
if ((current->euid != inode->i_uid) && !suser()) {
iput(inode);
return -EACCES;
}
inode->i_mode = (mode & 07777) | (inode->i_mode & ~07777);
inode->i_dirt = 1;
iput(inode);
return 0;
}
int sys_chown(const char * filename,int uid,int gid)
{
struct m_inode * inode;
if (!(inode=namei(filename)))
return -ENOENT;
if (!suser()) {
iput(inode);
return -EACCES;
}
inode->i_uid=uid;
inode->i_gid=gid;
inode->i_dirt=1;
iput(inode);
return 0;
}
int sys_open(const char * filename,int flag,int mode)
{
struct m_inode * inode;
struct file * f;
int i,fd;
mode &= 0777 & ~current->umask;
for(fd=0 ; fd<NR_OPEN ; fd++)
if (!current->filp[fd])
break;
if (fd>=NR_OPEN)
return -EINVAL;
current->close_on_exec &= ~(1<<fd);
f=0+file_table;
for (i=0 ; i<NR_FILE ; i++,f++)
if (!f->f_count) break;
if (i>=NR_FILE)
return -EINVAL;
(current->filp[fd]=f)->f_count++;
if ((i=open_namei(filename,flag,mode,&inode))<0) {
current->filp[fd]=NULL;
f->f_count=0;
return i;
}
/* ttys are somewhat special (ttyxx major==4, tty major==5) */
if (S_ISCHR(inode->i_mode))
if (MAJOR(inode->i_zone[0])==4) {
if (current->leader && current->tty<0) {
current->tty = MINOR(inode->i_zone[0]);
tty_table[current->tty].pgrp = current->pgrp;
}
} else if (MAJOR(inode->i_zone[0])==5)
if (current->tty<0) {
iput(inode);
current->filp[fd]=NULL;
f->f_count=0;
return -EPERM;
}
/* Likewise with block-devices: check for floppy_change */
if (S_ISBLK(inode->i_mode))
check_disk_change(inode->i_zone[0]);
f->f_mode = inode->i_mode;
f->f_flags = flag;
f->f_count = 1;
f->f_inode = inode;
f->f_pos = 0;
return (fd);
}
int sys_creat(const char * pathname, int mode)
{
return sys_open(pathname, O_CREAT | O_TRUNC, mode);
}
int sys_close(unsigned int fd)
{
struct file * filp;
if (fd >= NR_OPEN)
return -EINVAL;
current->close_on_exec &= ~(1<<fd);
if (!(filp = current->filp[fd]))
return -EINVAL;
current->filp[fd] = NULL;
if (filp->f_count == 0)
panic("Close: file count is 0");
if (--filp->f_count)
return (0);
iput(filp->f_inode);
return (0);
}
/*
* linux/fs/pipe.c
*
* (C) 1991 Linus Torvalds
*/
#include <signal.h>
#include <linux/sched.h>
#include <linux/mm.h> /* for get_free_page */
#include <asm/segment.h>
int read_pipe(struct m_inode * inode, char * buf, int count)
{
int chars, size, read = 0;
while (count>0) {
while (!(size=PIPE_SIZE(*inode))) {
wake_up(&inode->i_wait);
if (inode->i_count != 2) /* are there any writers? */
return read;
sleep_on(&inode->i_wait);
}
chars = PAGE_SIZE-PIPE_TAIL(*inode);
if (chars > count)
chars = count;
if (chars > size)
chars = size;
count -= chars;
read += chars;
size = PIPE_TAIL(*inode);
PIPE_TAIL(*inode) += chars;
PIPE_TAIL(*inode) &= (PAGE_SIZE-1);
while (chars-->0)
put_fs_byte(((char *)inode->i_size)[size++],buf++);
}
wake_up(&inode->i_wait);
return read;
}
int write_pipe(struct m_inode * inode, char * buf, int count)
{
int chars, size, written = 0;
while (count>0) {
while (!(size=(PAGE_SIZE-1)-PIPE_SIZE(*inode))) {
wake_up(&inode->i_wait);
if (inode->i_count != 2) { /* no readers */
current->signal |= (1<<(SIGPIPE-1));
return written?written:-1;
}
sleep_on(&inode->i_wait);
}
chars = PAGE_SIZE-PIPE_HEAD(*inode);
if (chars > count)
chars = count;
if (chars > size)
chars = size;
count -= chars;
written += chars;
size = PIPE_HEAD(*inode);
PIPE_HEAD(*inode) += chars;
PIPE_HEAD(*inode) &= (PAGE_SIZE-1);
while (chars-->0)
((char *)inode->i_size)[size++]=get_fs_byte(buf++);
}
wake_up(&inode->i_wait);
return written;
}
int sys_pipe(unsigned long * fildes)
{
struct m_inode * inode;
struct file * f[2];
int fd[2];
int i,j;
j=0;
for(i=0;j<2 && i<NR_FILE;i++)
if (!file_table[i].f_count)
(f[j++]=i+file_table)->f_count++;
if (j==1)
f[0]->f_count=0;
if (j<2)
return -1;
j=0;
for(i=0;j<2 && i<NR_OPEN;i++)
if (!current->filp[i]) {
current->filp[ fd[j]=i ] = f[j];
j++;
}
if (j==1)
current->filp[fd[0]]=NULL;
if (j<2) {
f[0]->f_count=f[1]->f_count=0;
return -1;
}
if (!(inode=get_pipe_inode())) {
current->filp[fd[0]] =
current->filp[fd[1]] = NULL;
f[0]->f_count = f[1]->f_count = 0;
return -1;
}
f[0]->f_inode = f[1]->f_inode = inode;
f[0]->f_pos = f[1]->f_pos = 0;
f[0]->f_mode = 1; /* read */
f[1]->f_mode = 2; /* write */
put_fs_long(fd[0],0+fildes);
put_fs_long(fd[1],1+fildes);
return 0;
}
/*
* linux/fs/read_write.c
*
* (C) 1991 Linus Torvalds
*/
#include <sys/stat.h>
#include <errno.h>
#include <sys/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <asm/segment.h>
extern int rw_char(int rw,int dev, char * buf, int count, off_t * pos);
extern int read_pipe(struct m_inode * inode, char * buf, int count);
extern int write_pipe(struct m_inode * inode, char * buf, int count);
extern int block_read(int dev, off_t * pos, char * buf, int count);
extern int block_write(int dev, off_t * pos, char * buf, int count);
extern int file_read(struct m_inode * inode, struct file * filp,
char * buf, int count);
extern int file_write(struct m_inode * inode, struct file * filp,
char * buf, int count);
int sys_lseek(unsigned int fd,off_t offset, int origin)
{
struct file * file;
int tmp;
if (fd >= NR_OPEN || !(file=current->filp[fd]) || !(file->f_inode)
|| !IS_SEEKABLE(MAJOR(file->f_inode->i_dev)))
return -EBADF;
if (file->f_inode->i_pipe)
return -ESPIPE;
switch (origin) {
case 0:
if (offset<0) return -EINVAL;
file->f_pos=offset;
break;
case 1:
if (file->f_pos+offset<0) return -EINVAL;
file->f_pos += offset;
break;
case 2:
if ((tmp=file->f_inode->i_size+offset) < 0)
return -EINVAL;
file->f_pos = tmp;
break;
default:
return -EINVAL;
}
return file->f_pos;
}
int sys_read(unsigned int fd,char * buf,int count)
{
struct file * file;
struct m_inode * inode;
if (fd>=NR_OPEN || count<0 || !(file=current->filp[fd]))
return -EINVAL;
if (!count)
return 0;
verify_area(buf,count);
inode = file->f_inode;
if (inode->i_pipe)
return (file->f_mode&1)?read_pipe(inode,buf,count):-EIO;
if (S_ISCHR(inode->i_mode))
return rw_char(READ,inode->i_zone[0],buf,count,&file->f_pos);
if (S_ISBLK(inode->i_mode))
return block_read(inode->i_zone[0],&file->f_pos,buf,count);
if (S_ISDIR(inode->i_mode) || S_ISREG(inode->i_mode)) {
if (count+file->f_pos > inode->i_size)
count = inode->i_size - file->f_pos;
if (count<=0)
return 0;
return file_read(inode,file,buf,count);
}
printk("(Read)inode->i_mode=%06o\n\r",inode->i_mode);
return -EINVAL;
}
int sys_write(unsigned int fd,char * buf,int count)
{
struct file * file;
struct m_inode * inode;
if (fd>=NR_OPEN || count <0 || !(file=current->filp[fd]))
return -EINVAL;
if (!count)
return 0;
inode=file->f_inode;
if (inode->i_pipe)
return (file->f_mode&2)?write_pipe(inode,buf,count):-EIO;
if (S_ISCHR(inode->i_mode))
return rw_char(WRITE,inode->i_zone[0],buf,count,&file->f_pos);
if (S_ISBLK(inode->i_mode))
return block_write(inode->i_zone[0],&file->f_pos,buf,count);
if (S_ISREG(inode->i_mode))
return file_write(inode,file,buf,count);
printk("(Write)inode->i_mode=%06o\n\r",inode->i_mode);
return -EINVAL;
}
/*
* linux/fs/stat.c
*
* (C) 1991 Linus Torvalds
*/
#include <errno.h>
#include <sys/stat.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <asm/segment.h>
static void cp_stat(struct m_inode * inode, struct stat * statbuf)
{
struct stat tmp;
int i;
verify_area(statbuf,sizeof (* statbuf));
tmp.st_dev = inode->i_dev;
tmp.st_ino = inode->i_num;
tmp.st_mode = inode->i_mode;
tmp.st_nlink = inode->i_nlinks;
tmp.st_uid = inode->i_uid;
tmp.st_gid = inode->i_gid;
tmp.st_rdev = inode->i_zone[0];
tmp.st_size = inode->i_size;
tmp.st_atime = inode->i_atime;
tmp.st_mtime = inode->i_mtime;
tmp.st_ctime = inode->i_ctime;
for (i=0 ; i<sizeof (tmp) ; i++)
put_fs_byte(((char *) &tmp)[i],&((char *) statbuf)[i]);
}
int sys_stat(char * filename, struct stat * statbuf)
{
struct m_inode * inode;
if (!(inode=namei(filename)))
return -ENOENT;
cp_stat(inode,statbuf);
iput(inode);
return 0;
}
int sys_fstat(unsigned int fd, struct stat * statbuf)
{
struct file * f;
struct m_inode * inode;
if (fd >= NR_OPEN || !(f=current->filp[fd]) || !(inode=f->f_inode))
return -EBADF;
cp_stat(inode,statbuf);
return 0;
}
/*
* linux/fs/super.c
*
* (C) 1991 Linus Torvalds
*/
/*
* super.c contains code to handle the super-block tables.
*/
#include <linux/config.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <asm/system.h>
#include <errno.h>
#include <sys/stat.h>
int sync_dev(int dev);
void wait_for_keypress(void);
/* set_bit uses setb, as gas doesn't recognize setc */
#define set_bit(bitnr,addr) ({ \
register int __res __asm__("ax"); \
__asm__("bt %2,%3;setb %%al":"=a" (__res):"a" (0),"r" (bitnr),"m" (*(addr))); \
__res; })
struct super_block super_block[NR_SUPER];
/* this is initialized in init/main.c */
int ROOT_DEV = 0;
static void lock_super(struct super_block * sb)
{
cli();
while (sb->s_lock)
sleep_on(&(sb->s_wait));
sb->s_lock = 1;
sti();
}
static void free_super(struct super_block * sb)
{
cli();
sb->s_lock = 0;
wake_up(&(sb->s_wait));
sti();
}
static void wait_on_super(struct super_block * sb)
{
cli();
while (sb->s_lock)
sleep_on(&(sb->s_wait));
sti();
}
struct super_block * get_super(int dev)
{
struct super_block * s;
if (!dev)
return NULL;
s = 0+super_block;
while (s < NR_SUPER+super_block)
if (s->s_dev == dev) {
wait_on_super(s);
if (s->s_dev == dev)
return s;
s = 0+super_block;
} else
s++;
return NULL;
}
void put_super(int dev)
{
struct super_block * sb;
struct m_inode * inode;
int i;
if (dev == ROOT_DEV) {
printk("root diskette changed: prepare for armageddon\n\r");
return;
}
if (!(sb = get_super(dev)))
return;
if (sb->s_imount) {
printk("Mounted disk changed - tssk, tssk\n\r");
return;
}
lock_super(sb);
sb->s_dev = 0;
for(i=0;i<I_MAP_SLOTS;i++)
brelse(sb->s_imap[i]);
for(i=0;i<Z_MAP_SLOTS;i++)
brelse(sb->s_zmap[i]);
free_super(sb);
return;
}
static struct super_block * read_super(int dev)
{
struct super_block * s;
struct buffer_head * bh;
int i,block;
if (!dev)
return NULL;
check_disk_change(dev);
if (s = get_super(dev))
return s;
for (s = 0+super_block ;; s++) {
if (s >= NR_SUPER+super_block)
return NULL;
if (!s->s_dev)
break;
}
s->s_dev = dev;
s->s_isup = NULL;
s->s_imount = NULL;
s->s_time = 0;
s->s_rd_only = 0;
s->s_dirt = 0;
lock_super(s);
if (!(bh = bread(dev,1))) {
s->s_dev=0;
free_super(s);
return NULL;
}
*((struct d_super_block *) s) =
*((struct d_super_block *) bh->b_data);
brelse(bh);
if (s->s_magic != SUPER_MAGIC) {
s->s_dev = 0;
free_super(s);
return NULL;
}
for (i=0;i<I_MAP_SLOTS;i++)
s->s_imap[i] = NULL;
for (i=0;i<Z_MAP_SLOTS;i++)
s->s_zmap[i] = NULL;
block=2;
for (i=0 ; i < s->s_imap_blocks ; i++)
if (s->s_imap[i]=bread(dev,block))
block++;
else
break;
for (i=0 ; i < s->s_zmap_blocks ; i++)
if (s->s_zmap[i]=bread(dev,block))
block++;
else
break;
if (block != 2+s->s_imap_blocks+s->s_zmap_blocks) {
for(i=0;i<I_MAP_SLOTS;i++)
brelse(s->s_imap[i]);
for(i=0;i<Z_MAP_SLOTS;i++)
brelse(s->s_zmap[i]);
s->s_dev=0;
free_super(s);
return NULL;
}
s->s_imap[0]->b_data[0] |= 1;
s->s_zmap[0]->b_data[0] |= 1;
free_super(s);
return s;
}
int sys_umount(char * dev_name)
{
struct m_inode * inode;
struct super_block * sb;
int dev;
if (!(inode=namei(dev_name)))
return -ENOENT;
dev = inode->i_zone[0];
if (!S_ISBLK(inode->i_mode)) {
iput(inode);
return -ENOTBLK;
}
iput(inode);
if (dev==ROOT_DEV)
return -EBUSY;
if (!(sb=get_super(dev)) || !(sb->s_imount))
return -ENOENT;
if (!sb->s_imount->i_mount)
printk("Mounted inode has i_mount=0\n");
for (inode=inode_table+0 ; inode<inode_table+NR_INODE ; inode++)
if (inode->i_dev==dev && inode->i_count)
return -EBUSY;
sb->s_imount->i_mount=0;
iput(sb->s_imount);
sb->s_imount = NULL;
iput(sb->s_isup);
sb->s_isup = NULL;
put_super(dev);
sync_dev(dev);
return 0;
}
int sys_mount(char * dev_name, char * dir_name, int rw_flag)
{
struct m_inode * dev_i, * dir_i;
struct super_block * sb;
int dev;
if (!(dev_i=namei(dev_name)))
return -ENOENT;
dev = dev_i->i_zone[0];
if (!S_ISBLK(dev_i->i_mode)) {
iput(dev_i);
return -EPERM;
}
iput(dev_i);
if (!(dir_i=namei(dir_name)))
return -ENOENT;
if (dir_i->i_count != 1 || dir_i->i_num == ROOT_INO) {
iput(dir_i);
return -EBUSY;
}
if (!S_ISDIR(dir_i->i_mode)) {
iput(dir_i);
return -EPERM;
}
if (!(sb=read_super(dev))) {
iput(dir_i);
return -EBUSY;
}
if (sb->s_imount) {
iput(dir_i);
return -EBUSY;
}
if (dir_i->i_mount) {
iput(dir_i);
return -EPERM;
}
sb->s_imount=dir_i;
dir_i->i_mount=1;
dir_i->i_dirt=1; /* NOTE! we don't iput(dir_i) */
return 0; /* we do that in umount */
}
void mount_root(void)
{
int i,free;
struct super_block * p;
struct m_inode * mi;
if (32 != sizeof (struct d_inode))
panic("bad i-node size");
for(i=0;i<NR_FILE;i++)
file_table[i].f_count=0;
if (MAJOR(ROOT_DEV) == 2) {
printk("Insert root floppy and press ENTER");
wait_for_keypress();
}
for(p = &super_block[0] ; p < &super_block[NR_SUPER] ; p++) {
p->s_dev = 0;
p->s_lock = 0;
p->s_wait = NULL;
}
if (!(p=read_super(ROOT_DEV)))
panic("Unable to mount root");
if (!(mi=iget(ROOT_DEV,ROOT_INO)))
panic("Unable to read root i-node");
mi->i_count += 3 ; /* NOTE! it is logically used 4 times, not 1 */
p->s_isup = p->s_imount = mi;
current->pwd = mi;
current->root = mi;
free=0;
i=p->s_nzones;
while (-- i >= 0)
if (!set_bit(i&8191,p->s_zmap[i>>13]->b_data))
free++;
printk("%d/%d free blocks\n\r",free,p->s_nzones);
free=0;
i=p->s_ninodes+1;
while (-- i >= 0)
if (!set_bit(i&8191,p->s_imap[i>>13]->b_data))
free++;
printk("%d/%d free inodes\n\r",free,p->s_ninodes);
}
/*
* linux/fs/truncate.c
*
* (C) 1991 Linus Torvalds
*/
#include <linux/sched.h>
#include <sys/stat.h>
static void free_ind(int dev,int block)
{
struct buffer_head * bh;
unsigned short * p;
int i;
if (!block)
return;
if (bh=bread(dev,block)) {
p = (unsigned short *) bh->b_data;
for (i=0;i<512;i++,p++)
if (*p)
free_block(dev,*p);
brelse(bh);
}
free_block(dev,block);
}
static void free_dind(int dev,int block)
{
struct buffer_head * bh;
unsigned short * p;
int i;
if (!block)
return;
if (bh=bread(dev,block)) {
p = (unsigned short *) bh->b_data;
for (i=0;i<512;i++,p++)
if (*p)
free_ind(dev,*p);
brelse(bh);
}
free_block(dev,block);
}
void truncate(struct m_inode * inode)
{
int i;
if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
return;
for (i=0;i<7;i++)
if (inode->i_zone[i]) {
free_block(inode->i_dev,inode->i_zone[i]);
inode->i_zone[i]=0;
}
free_ind(inode->i_dev,inode->i_zone[7]);
free_dind(inode->i_dev,inode->i_zone[8]);
inode->i_zone[7] = inode->i_zone[8] = 0;
inode->i_size = 0;
inode->i_dirt = 1;
inode->i_mtime = inode->i_ctime = CURRENT_TIME;
}
#ifndef _A_OUT_H
#define _A_OUT_H
#define __GNU_EXEC_MACROS__
struct exec {
unsigned long a_magic; /* Use macros N_MAGIC, etc for access */
unsigned a_text; /* length of text, in bytes */
unsigned a_data; /* length of data, in bytes */
unsigned a_bss; /* length of uninitialized data area for file, in bytes */
unsigned a_syms; /* length of symbol table data in file, in bytes */
unsigned a_entry; /* start address */
unsigned a_trsize; /* length of relocation info for text, in bytes */
unsigned a_drsize; /* length of relocation info for data, in bytes */
};
#ifndef N_MAGIC
#define N_MAGIC(exec) ((exec).a_magic)
#endif
#ifndef OMAGIC
/* Code indicating object file or impure executable. */
#define OMAGIC 0407
/* Code indicating pure executable. */
#define NMAGIC 0410
/* Code indicating demand-paged executable. */
#define ZMAGIC 0413
#endif /* not OMAGIC */
#ifndef N_BADMAG
#define N_BADMAG(x) \
(N_MAGIC(x) != OMAGIC && N_MAGIC(x) != NMAGIC \
&& N_MAGIC(x) != ZMAGIC)
#endif
#define _N_BADMAG(x) \
(N_MAGIC(x) != OMAGIC && N_MAGIC(x) != NMAGIC \
&& N_MAGIC(x) != ZMAGIC)
#define _N_HDROFF(x) (SEGMENT_SIZE - sizeof (struct exec))
#ifndef N_TXTOFF
#define N_TXTOFF(x) \
(N_MAGIC(x) == ZMAGIC ? _N_HDROFF((x)) + sizeof (struct exec) : sizeof (struct exec))
#endif
#ifndef N_DATOFF
#define N_DATOFF(x) (N_TXTOFF(x) + (x).a_text)
#endif
#ifndef N_TRELOFF
#define N_TRELOFF(x) (N_DATOFF(x) + (x).a_data)
#endif
#ifndef N_DRELOFF
#define N_DRELOFF(x) (N_TRELOFF(x) + (x).a_trsize)
#endif
#ifndef N_SYMOFF
#define N_SYMOFF(x) (N_DRELOFF(x) + (x).a_drsize)
#endif
#ifndef N_STROFF
#define N_STROFF(x) (N_SYMOFF(x) + (x).a_syms)
#endif
/* Address of text segment in memory after it is loaded. */
#ifndef N_TXTADDR
#define N_TXTADDR(x) 0
#endif
/* Address of data segment in memory after it is loaded.
Note that it is up to you to define SEGMENT_SIZE
on machines not listed here. */
#if defined(vax) || defined(hp300) || defined(pyr)
#define SEGMENT_SIZE PAGE_SIZE
#endif
#ifdef hp300
#define PAGE_SIZE 4096
#endif
#ifdef sony
#define SEGMENT_SIZE 0x2000
#endif /* Sony. */
#ifdef is68k
#define SEGMENT_SIZE 0x20000
#endif
#if defined(m68k) && defined(PORTAR)
#define PAGE_SIZE 0x400
#define SEGMENT_SIZE PAGE_SIZE
#endif
#define PAGE_SIZE 4096
#define SEGMENT_SIZE 1024
#define _N_SEGMENT_ROUND(x) (((x) + SEGMENT_SIZE - 1) & ~(SEGMENT_SIZE - 1))
#define _N_TXTENDADDR(x) (N_TXTADDR(x)+(x).a_text)
#ifndef N_DATADDR
#define N_DATADDR(x) \
(N_MAGIC(x)==OMAGIC? (_N_TXTENDADDR(x)) \
: (_N_SEGMENT_ROUND (_N_TXTENDADDR(x))))
#endif
/* Address of bss segment in memory after it is loaded. */
#ifndef N_BSSADDR
#define N_BSSADDR(x) (N_DATADDR(x) + (x).a_data)
#endif
#ifndef N_NLIST_DECLARED
struct nlist {
union {
char *n_name;
struct nlist *n_next;
long n_strx;
} n_un;
unsigned char n_type;
char n_other;
short n_desc;
unsigned long n_value;
};
#endif
#ifndef N_UNDF
#define N_UNDF 0
#endif
#ifndef N_ABS
#define N_ABS 2
#endif
#ifndef N_TEXT
#define N_TEXT 4
#endif
#ifndef N_DATA
#define N_DATA 6
#endif
#ifndef N_BSS
#define N_BSS 8
#endif
#ifndef N_COMM
#define N_COMM 18
#endif
#ifndef N_FN
#define N_FN 15
#endif
#ifndef N_EXT
#define N_EXT 1
#endif
#ifndef N_TYPE
#define N_TYPE 036
#endif
#ifndef N_STAB
#define N_STAB 0340
#endif
/* The following type indicates the definition of a symbol as being
an indirect reference to another symbol. The other symbol
appears as an undefined reference, immediately following this symbol.
Indirection is asymmetrical. The other symbol's value will be used
to satisfy requests for the indirect symbol, but not vice versa.
If the other symbol does not have a definition, libraries will
be searched to find a definition. */
#define N_INDR 0xa
/* The following symbols refer to set elements.
All the N_SET[ATDB] symbols with the same name form one set.
Space is allocated for the set in the text section, and each set
element's value is stored into one word of the space.
The first word of the space is the length of the set (number of elements).
The address of the set is made into an N_SETV symbol
whose name is the same as the name of the set.
This symbol acts like a N_DATA global symbol
in that it can satisfy undefined external references. */
/* These appear as input to LD, in a .o file. */
#define N_SETA 0x14 /* Absolute set element symbol */
#define N_SETT 0x16 /* Text set element symbol */
#define N_SETD 0x18 /* Data set element symbol */
#define N_SETB 0x1A /* Bss set element symbol */
/* This is output from LD. */
#define N_SETV 0x1C /* Pointer to set vector in data area. */
#ifndef N_RELOCATION_INFO_DECLARED
/* This structure describes a single relocation to be performed.
The text-relocation section of the file is a vector of these structures,
all of which apply to the text section.
Likewise, the data-relocation section applies to the data section. */
struct relocation_info
{
/* Address (within segment) to be relocated. */
int r_address;
/* The meaning of r_symbolnum depends on r_extern. */
unsigned int r_symbolnum:24;
/* Nonzero means value is a pc-relative offset
and it should be relocated for changes in its own address
as well as for changes in the symbol or section specified. */
unsigned int r_pcrel:1;
/* Length (as exponent of 2) of the field to be relocated.
Thus, a value of 2 indicates 1<<2 bytes. */
unsigned int r_length:2;
/* 1 => relocate with value of symbol.
r_symbolnum is the index of the symbol
in file's the symbol table.
0 => relocate with the address of a segment.
r_symbolnum is N_TEXT, N_DATA, N_BSS or N_ABS
(the N_EXT bit may be set also, but signifies nothing). */
unsigned int r_extern:1;
/* Four bits that aren't used, but when writing an object file
it is desirable to clear them. */
unsigned int r_pad:4;
};
#endif /* no N_RELOCATION_INFO_DECLARED. */
#endif /* __A_OUT_GNU_H__ */
#define outb(value,port) \
__asm__ ("outb %%al,%%dx"::"a" (value),"d" (port))
#define inb(port) ({ \
unsigned char _v; \
__asm__ volatile ("inb %%dx,%%al":"=a" (_v):"d" (port)); \
_v; \
})
#define outb_p(value,port) \
__asm__ ("outb %%al,%%dx\n" \
"\tjmp 1f\n" \
"1:\tjmp 1f\n" \
"1:"::"a" (value),"d" (port))
#define inb_p(port) ({ \
unsigned char _v; \
__asm__ volatile ("inb %%dx,%%al\n" \
"\tjmp 1f\n" \
"1:\tjmp 1f\n" \
"1:":"=a" (_v):"d" (port)); \
_v; \
})
/*
* NOTE!!! memcpy(dest,src,n) assumes ds=es=normal data segment. This
* goes for all kernel functions (ds=es=kernel space, fs=local data,
* gs=null), as well as for all well-behaving user programs (ds=es=
* user data space). This is NOT a bug, as any user program that changes
* es deserves to die if it isn't careful.
*/
#define memcpy(dest,src,n) ({ \
void * _res = dest; \
__asm__ ("cld;rep;movsb" \
::"D" ((long)(_res)),"S" ((long)(src)),"c" ((long) (n)) \
:"di","si","cx"); \
_res; \
})
extern inline unsigned char get_fs_byte(const char * addr)
{
unsigned register char _v;
__asm__ ("movb %%fs:%1,%0":"=r" (_v):"m" (*addr));
return _v;
}
extern inline unsigned short get_fs_word(const unsigned short *addr)
{
unsigned short _v;
__asm__ ("movw %%fs:%1,%0":"=r" (_v):"m" (*addr));
return _v;
}
extern inline unsigned long get_fs_long(const unsigned long *addr)
{
unsigned long _v;
__asm__ ("movl %%fs:%1,%0":"=r" (_v):"m" (*addr)); \
return _v;
}
extern inline void put_fs_byte(char val,char *addr)
{
__asm__ ("movb %0,%%fs:%1"::"r" (val),"m" (*addr));
}
extern inline void put_fs_word(short val,short * addr)
{
__asm__ ("movw %0,%%fs:%1"::"r" (val),"m" (*addr));
}
extern inline void put_fs_long(unsigned long val,unsigned long * addr)
{
__asm__ ("movl %0,%%fs:%1"::"r" (val),"m" (*addr));
}
/*
* Someone who knows GNU asm better than I should double check the followig.
* It seems to work, but I don't know if I'm doing something subtly wrong.
* --- TYT, 11/24/91
* [ nothing wrong here, Linus ]
*/
extern inline unsigned long get_fs()
{
unsigned short _v;
__asm__("mov %%fs,%%ax":"=a" (_v):);
return _v;
}
extern inline unsigned long get_ds()
{
unsigned short _v;
__asm__("mov %%ds,%%ax":"=a" (_v):);
return _v;
}
extern inline void set_fs(unsigned long val)
{
__asm__("mov %0,%%fs"::"a" ((unsigned short) val));
}
#define move_to_user_mode() \
__asm__ ("movl %%esp,%%eax\n\t" \
"pushl $0x17\n\t" \
"pushl %%eax\n\t" \
"pushfl\n\t" \
"pushl $0x0f\n\t" \
"pushl $1f\n\t" \
"iret\n" \
"1:\tmovl $0x17,%%eax\n\t" \
"movw %%ax,%%ds\n\t" \
"movw %%ax,%%es\n\t" \
"movw %%ax,%%fs\n\t" \
"movw %%ax,%%gs" \
:::"ax")
#define sti() __asm__ ("sti"::)
#define cli() __asm__ ("cli"::)
#define nop() __asm__ ("nop"::)
#define iret() __asm__ ("iret"::)
#define _set_gate(gate_addr,type,dpl,addr) \
__asm__ ("movw %%dx,%%ax\n\t" \
"movw %0,%%dx\n\t" \
"movl %%eax,%1\n\t" \
"movl %%edx,%2" \
: \
: "i" ((short) (0x8000+(dpl<<13)+(type<<8))), \
"o" (*((char *) (gate_addr))), \
"o" (*(4+(char *) (gate_addr))), \
"d" ((char *) (addr)),"a" (0x00080000))
#define set_intr_gate(n,addr) \
_set_gate(&idt[n],14,0,addr)
#define set_trap_gate(n,addr) \
_set_gate(&idt[n],15,0,addr)
#define set_system_gate(n,addr) \
_set_gate(&idt[n],15,3,addr)
#define _set_seg_desc(gate_addr,type,dpl,base,limit) {\
*(gate_addr) = ((base) & 0xff000000) | \
(((base) & 0x00ff0000)>>16) | \
((limit) & 0xf0000) | \
((dpl)<<13) | \
(0x00408000) | \
((type)<<8); \
*((gate_addr)+1) = (((base) & 0x0000ffff)<<16) | \
((limit) & 0x0ffff); }
#define _set_tssldt_desc(n,addr,type) \
__asm__ ("movw $104,%1\n\t" \
"movw %%ax,%2\n\t" \
"rorl $16,%%eax\n\t" \
"movb %%al,%3\n\t" \
"movb $" type ",%4\n\t" \
"movb $0x00,%5\n\t" \
"movb %%ah,%6\n\t" \
"rorl $16,%%eax" \
::"a" (addr), "m" (*(n)), "m" (*(n+2)), "m" (*(n+4)), \
"m" (*(n+5)), "m" (*(n+6)), "m" (*(n+7)) \
)
#define set_tss_desc(n,addr) _set_tssldt_desc(((char *) (n)),addr,"0x89")
#define set_ldt_desc(n,addr) _set_tssldt_desc(((char *) (n)),addr,"0x82")
#ifndef _CONST_H
#define _CONST_H
#define BUFFER_END 0x200000
#define I_TYPE 0170000
#define I_DIRECTORY 0040000
#define I_REGULAR 0100000
#define I_BLOCK_SPECIAL 0060000
#define I_CHAR_SPECIAL 0020000
#define I_NAMED_PIPE 0010000
#define I_SET_UID_BIT 0004000
#define I_SET_GID_BIT 0002000
#endif
#ifndef _CTYPE_H
#define _CTYPE_H
#define _U 0x01 /* upper */
#define _L 0x02 /* lower */
#define _D 0x04 /* digit */
#define _C 0x08 /* cntrl */
#define _P 0x10 /* punct */
#define _S 0x20 /* white space (space/lf/tab) */
#define _X 0x40 /* hex digit */
#define _SP 0x80 /* hard space (0x20) */
extern unsigned char _ctype[];
extern char _ctmp;
#define isalnum(c) ((_ctype+1)[c]&(_U|_L|_D))
#define isalpha(c) ((_ctype+1)[c]&(_U|_L))
#define iscntrl(c) ((_ctype+1)[c]&(_C))
#define isdigit(c) ((_ctype+1)[c]&(_D))
#define isgraph(c) ((_ctype+1)[c]&(_P|_U|_L|_D))
#define islower(c) ((_ctype+1)[c]&(_L))
#define isprint(c) ((_ctype+1)[c]&(_P|_U|_L|_D|_SP))
#define ispunct(c) ((_ctype+1)[c]&(_P))
#define isspace(c) ((_ctype+1)[c]&(_S))
#define isupper(c) ((_ctype+1)[c]&(_U))
#define isxdigit(c) ((_ctype+1)[c]&(_D|_X))
#define isascii(c) (((unsigned) c)<=0x7f)
#define toascii(c) (((unsigned) c)&0x7f)
#define tolower(c) (_ctmp=c,isupper(_ctmp)?_ctmp-('A'-'a'):_ctmp)
#define toupper(c) (_ctmp=c,islower(_ctmp)?_ctmp-('a'-'A'):_ctmp)
#endif
#ifndef _ERRNO_H
#define _ERRNO_H
/*
* ok, as I hadn't got any other source of information about
* possible error numbers, I was forced to use the same numbers
* as minix.
* Hopefully these are posix or something. I wouldn't know (and posix
* isn't telling me - they want $$$ for their f***ing standard).
*
* We don't use the _SIGN cludge of minix, so kernel returns must
* see to the sign by themselves.
*
* NOTE! Remember to change strerror() if you change this file!
*/
extern int errno;
#define ERROR 99
#define EPERM 1
#define ENOENT 2
#define ESRCH 3
#define EINTR 4
#define EIO 5
#define ENXIO 6
#define E2BIG 7
#define ENOEXEC 8
#define EBADF 9
#define ECHILD 10
#define EAGAIN 11
#define ENOMEM 12
#define EACCES 13
#define EFAULT 14
#define ENOTBLK 15
#define EBUSY 16
#define EEXIST 17
#define EXDEV 18
#define ENODEV 19
#define ENOTDIR 20
#define EISDIR 21
#define EINVAL 22
#define ENFILE 23
#define EMFILE 24
#define ENOTTY 25
#define ETXTBSY 26
#define EFBIG 27
#define ENOSPC 28
#define ESPIPE 29
#define EROFS 30
#define EMLINK 31
#define EPIPE 32
#define EDOM 33
#define ERANGE 34
#define EDEADLK 35
#define ENAMETOOLONG 36
#define ENOLCK 37
#define ENOSYS 38
#define ENOTEMPTY 39
#endif
#ifndef _FCNTL_H
#define _FCNTL_H
#include <sys/types.h>
/* open/fcntl - NOCTTY, NDELAY isn't implemented yet */
#define O_ACCMODE 00003
#define O_RDONLY 00
#define O_WRONLY 01
#define O_RDWR 02
#define O_CREAT 00100 /* not fcntl */
#define O_EXCL 00200 /* not fcntl */
#define O_NOCTTY 00400 /* not fcntl */
#define O_TRUNC 01000 /* not fcntl */
#define O_APPEND 02000
#define O_NONBLOCK 04000 /* not fcntl */
#define O_NDELAY O_NONBLOCK
/* Defines for fcntl-commands. Note that currently
* locking isn't supported, and other things aren't really
* tested.
*/
#define F_DUPFD 0 /* dup */
#define F_GETFD 1 /* get f_flags */
#define F_SETFD 2 /* set f_flags */
#define F_GETFL 3 /* more flags (cloexec) */
#define F_SETFL 4
#define F_GETLK 5 /* not implemented */
#define F_SETLK 6
#define F_SETLKW 7
/* for F_[GET|SET]FL */
#define FD_CLOEXEC 1 /* actually anything with low bit set goes */
/* Ok, these are locking features, and aren't implemented at any
* level. POSIX wants them.
*/
#define F_RDLCK 0
#define F_WRLCK 1
#define F_UNLCK 2
/* Once again - not implemented, but ... */
struct flock {
short l_type;
short l_whence;
off_t l_start;
off_t l_len;
pid_t l_pid;
};
extern int creat(const char * filename,mode_t mode);
extern int fcntl(int fildes,int cmd, ...);
extern int open(const char * filename, int flags, ...);
#endif
#ifndef _CONFIG_H
#define _CONFIG_H
/*
* The root-device is no longer hard-coded. You can change the default
* root-device by changing the line ROOT_DEV = XXX in boot/bootsect.s
*/
/*
* define your keyboard here -
* KBD_FINNISH for Finnish keyboards
* KBD_US for US-type
* KBD_GR for German keyboards
* KBD_FR for Frech keyboard
*/
/*#define KBD_US */
/*#define KBD_GR */
/*#define KBD_FR */
#define KBD_FINNISH
/*
* Normally, Linux can get the drive parameters from the BIOS at
* startup, but if this for some unfathomable reason fails, you'd
* be left stranded. For this case, you can define HD_TYPE, which
* contains all necessary info on your harddisk.
*
* The HD_TYPE macro should look like this:
*
* #define HD_TYPE { head, sect, cyl, wpcom, lzone, ctl}
*
* In case of two harddisks, the info should be sepatated by
* commas:
*
* #define HD_TYPE { h,s,c,wpcom,lz,ctl },{ h,s,c,wpcom,lz,ctl }
*/
/*
This is an example, two drives, first is type 2, second is type 3:
#define HD_TYPE { 4,17,615,300,615,8 }, { 6,17,615,300,615,0 }
NOTE: ctl is 0 for all drives with heads<=8, and ctl=8 for drives
with more than 8 heads.
If you want the BIOS to tell what kind of drive you have, just
leave HD_TYPE undefined. This is the normal thing to do.
*/
#endif
/*
* This file contains some defines for the floppy disk controller.
* Various sources. Mostly "IBM Microcomputers: A Programmers
* Handbook", Sanches and Canton.
*/
#ifndef _FDREG_H
#define _FDREG_H
extern int ticks_to_floppy_on(unsigned int nr);
extern void floppy_on(unsigned int nr);
extern void floppy_off(unsigned int nr);
extern void floppy_select(unsigned int nr);
extern void floppy_deselect(unsigned int nr);
/* Fd controller regs. S&C, about page 340 */
#define FD_STATUS 0x3f4
#define FD_DATA 0x3f5
#define FD_DOR 0x3f2 /* Digital Output Register */
#define FD_DIR 0x3f7 /* Digital Input Register (read) */
#define FD_DCR 0x3f7 /* Diskette Control Register (write)*/
/* Bits of main status register */
#define STATUS_BUSYMASK 0x0F /* drive busy mask */
#define STATUS_BUSY 0x10 /* FDC busy */
#define STATUS_DMA 0x20 /* 0- DMA mode */
#define STATUS_DIR 0x40 /* 0- cpu->fdc */
#define STATUS_READY 0x80 /* Data reg ready */
/* Bits of FD_ST0 */
#define ST0_DS 0x03 /* drive select mask */
#define ST0_HA 0x04 /* Head (Address) */
#define ST0_NR 0x08 /* Not Ready */
#define ST0_ECE 0x10 /* Equipment chech error */
#define ST0_SE 0x20 /* Seek end */
#define ST0_INTR 0xC0 /* Interrupt code mask */
/* Bits of FD_ST1 */
#define ST1_MAM 0x01 /* Missing Address Mark */
#define ST1_WP 0x02 /* Write Protect */
#define ST1_ND 0x04 /* No Data - unreadable */
#define ST1_OR 0x10 /* OverRun */
#define ST1_CRC 0x20 /* CRC error in data or addr */
#define ST1_EOC 0x80 /* End Of Cylinder */
/* Bits of FD_ST2 */
#define ST2_MAM 0x01 /* Missing Addess Mark (again) */
#define ST2_BC 0x02 /* Bad Cylinder */
#define ST2_SNS 0x04 /* Scan Not Satisfied */
#define ST2_SEH 0x08 /* Scan Equal Hit */
#define ST2_WC 0x10 /* Wrong Cylinder */
#define ST2_CRC 0x20 /* CRC error in data field */
#define ST2_CM 0x40 /* Control Mark = deleted */
/* Bits of FD_ST3 */
#define ST3_HA 0x04 /* Head (Address) */
#define ST3_TZ 0x10 /* Track Zero signal (1=track 0) */
#define ST3_WP 0x40 /* Write Protect */
/* Values for FD_COMMAND */
#define FD_RECALIBRATE 0x07 /* move to track 0 */
#define FD_SEEK 0x0F /* seek track */
#define FD_READ 0xE6 /* read with MT, MFM, SKip deleted */
#define FD_WRITE 0xC5 /* write with MT, MFM */
#define FD_SENSEI 0x08 /* Sense Interrupt Status */
#define FD_SPECIFY 0x03 /* specify HUT etc */
/* DMA commands */
#define DMA_READ 0x46
#define DMA_WRITE 0x4A
#endif
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/*
* This file contains some defines for the AT-hd-controller.
* Various sources. Check out some definitions (see comments with
* a ques).
*/
#ifndef _HDREG_H
#define _HDREG_H
/* Hd controller regs. Ref: IBM AT Bios-listing */
#define HD_DATA 0x1f0 /* _CTL when writing */
#define HD_ERROR 0x1f1 /* see err-bits */
#define HD_NSECTOR 0x1f2 /* nr of sectors to read/write */
#define HD_SECTOR 0x1f3 /* starting sector */
#define HD_LCYL 0x1f4 /* starting cylinder */
#define HD_HCYL 0x1f5 /* high byte of starting cyl */
#define HD_CURRENT 0x1f6 /* 101dhhhh , d=drive, hhhh=head */
#define HD_STATUS 0x1f7 /* see status-bits */
#define HD_PRECOMP HD_ERROR /* same io address, read=error, write=precomp */
#define HD_COMMAND HD_STATUS /* same io address, read=status, write=cmd */
#define HD_CMD 0x3f6
/* Bits of HD_STATUS */
#define ERR_STAT 0x01
#define INDEX_STAT 0x02
#define ECC_STAT 0x04 /* Corrected error */
#define DRQ_STAT 0x08
#define SEEK_STAT 0x10
#define WRERR_STAT 0x20
#define READY_STAT 0x40
#define BUSY_STAT 0x80
/* Values for HD_COMMAND */
#define WIN_RESTORE 0x10
#define WIN_READ 0x20
#define WIN_WRITE 0x30
#define WIN_VERIFY 0x40
#define WIN_FORMAT 0x50
#define WIN_INIT 0x60
#define WIN_SEEK 0x70
#define WIN_DIAGNOSE 0x90
#define WIN_SPECIFY 0x91
/* Bits for HD_ERROR */
#define MARK_ERR 0x01 /* Bad address mark ? */
#define TRK0_ERR 0x02 /* couldn't find track 0 */
#define ABRT_ERR 0x04 /* ? */
#define ID_ERR 0x10 /* ? */
#define ECC_ERR 0x40 /* ? */
#define BBD_ERR 0x80 /* ? */
struct partition {
unsigned char boot_ind; /* 0x80 - active (unused) */
unsigned char head; /* ? */
unsigned char sector; /* ? */
unsigned char cyl; /* ? */
unsigned char sys_ind; /* ? */
unsigned char end_head; /* ? */
unsigned char end_sector; /* ? */
unsigned char end_cyl; /* ? */
unsigned int start_sect; /* starting sector counting from 0 */
unsigned int nr_sects; /* nr of sectors in partition */
};
#endif
#ifndef _HEAD_H
#define _HEAD_H
typedef struct desc_struct {
unsigned long a,b;
} desc_table[256];
extern unsigned long pg_dir[1024];
extern desc_table idt,gdt;
#define GDT_NUL 0
#define GDT_CODE 1
#define GDT_DATA 2
#define GDT_TMP 3
#define LDT_NUL 0
#define LDT_CODE 1
#define LDT_DATA 2
#endif
/*
* 'kernel.h' contains some often-used function prototypes etc
*/
void verify_area(void * addr,int count);
volatile void panic(const char * str);
int printf(const char * fmt, ...);
int printk(const char * fmt, ...);
int tty_write(unsigned ch,char * buf,int count);
void * malloc(unsigned int size);
void free_s(void * obj, int size);
#define free(x) free_s((x), 0)
/*
* This is defined as a macro, but at some point this might become a
* real subroutine that sets a flag if it returns true (to do
* BSD-style accounting where the process is flagged if it uses root
* privs). The implication of this is that you should do normal
* permissions checks first, and check suser() last.
*/
#define suser() (current->euid == 0)
#ifndef _MM_H
#define _MM_H
#define PAGE_SIZE 4096
extern unsigned long get_free_page(void);
extern unsigned long put_page(unsigned long page,unsigned long address);
extern void free_page(unsigned long addr);
#endif
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#ifndef _STDDEF_H
#define _STDDEF_H
#ifndef _PTRDIFF_T
#define _PTRDIFF_T
typedef long ptrdiff_t;
#endif
#ifndef _SIZE_T
#define _SIZE_T
typedef unsigned long size_t;
#endif
#undef NULL
#define NULL ((void *)0)
#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
#endif
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