ref: 438383b2ec098fb86af9d13f1e40cc6c212a8353
parent: c7f7f5bbdf7360e20a5a93a613964f9ea3926ca4
author: cinap_lenrek <cinap_lenrek@localhost>
date: Wed Apr 20 06:49:54 EDT 2011
9boot: pxe/kernel memory overlap problem, add unload function
--- a/sys/src/boot/pc/a20.s
+++ b/sys/src/boot/pc/a20.s
@@ -4,16 +4,14 @@
TEXT a20(SB), $0
CALL rmode16(SB)
- STI
+ CALL16(spllo(SB))
LWI(0x2401, rAX)
BIOSCALL(0x15)
JC _biosfail
- CLI
CALL16(pmode32(SB))
RET
_biosfail:
- CLI
CALL16(pmode32(SB))
CALL a20wait(SB)
--- a/sys/src/boot/pc/fat.c
+++ b/sys/src/boot/pc/fat.c
@@ -63,6 +63,11 @@
int readsect(ulong drive, ulong lba, void *buf);
+void
+unload(void)
+{+}
+
int
read(void *f, void *data, int len)
{--- a/sys/src/boot/pc/fns.h
+++ b/sys/src/boot/pc/fns.h
@@ -16,6 +16,7 @@
int read(void *f, void *data, int len);
int readn(void *f, void *data, int len);
void close(void *f);
+void unload(void);
void memset(void *p, int v, int n);
void memmove(void *dst, void *src, int n);
--- a/sys/src/boot/pc/iso.c
+++ b/sys/src/boot/pc/iso.c
@@ -39,6 +39,11 @@
int readsect(ulong drive, ulong lba, void *buf);
+void
+unload(void)
+{+}
+
int
read(void *f, void *data, int len)
{--- a/sys/src/boot/pc/l.s
+++ b/sys/src/boot/pc/l.s
@@ -79,9 +79,6 @@
JMP _segret
TEXT rmode16x(SB), $0
- /* reload idt */
- SEGSS; LIDT(tidtptr(SB))
-
/* disable protected mode */
MFCR(rCR0, rCX)
ANDB $0xfe, CL
@@ -124,10 +121,6 @@
WORD $(5*8)
LONG $tgdt(SB)
-TEXT tidtptr(SB), $0
- WORD $0x3ff
- LONG $0
-
TEXT jump(SB), $0
MOVL 4(SP), AX
JMP *AX
@@ -180,6 +173,33 @@
#ifdef PXE
+TEXT pxeinit(SB), $0
+ CALL rmode16(SB)
+
+ /* get pxe env structure in ES:BX */
+ LWI(0x5650, rAX)
+ BIOSCALL(0x1A)
+ JC _pret32
+
+ /* !PXE or PXEENV+ signature */
+ SEGES; LXW(0, xBX, rAX)
+ CMPI((('!'<<0)|('P'<<8)), rAX)+ JEQ _getentry
+ CMPI((('P'<<0)|('X'<<8)), rAX)+ JNE _pret32
+
+ SEGES; LXW(0x2A, xBX, rAX)
+ SEGES; LXW(0x28, xBX, rBX)
+ MTSR(rAX, rES)
+
+_getentry:
+ SEGES; LXW(0x12, xBX, rAX)
+ SW(rAX, pxepseg(SB))
+ SEGES; LXW(0x10, xBX, rAX)
+ SW(rAX, pxepoff(SB))
+ CLR(rAX)
+ JMP _pret32
+
TEXT pxecallret(SB), $0
ADDI(6, rSP)
JMP _pret32
@@ -200,26 +220,9 @@
PUSHR(rCX)
PUSHI(pxecallret(SB))
- /* get pxe env structure in ES:BX */
- LWI(0x5650, rAX)
- BIOSCALL(0x1A)
- JC _farret
-
- /* !PXE or PXEENV+ signature */
- SEGES; LXW(0, xBX, rAX)
- CMPI((('!'<<0)|('P'<<8)), rAX)- JEQ _getentry
- CMPI((('P'<<0)|('X'<<8)), rAX)- JNE _farret
-
- SEGES; LXW(0x2A, xBX, rAX)
- SEGES; LXW(0x28, xBX, rBX)
- MTSR(rAX, rES)
-
-_getentry:
- SEGES; LXW(0x12, xBX, rAX)
+ LW(pxepseg(SB), rAX)
PUSHR(rAX)
- SEGES; LXW(0x10, xBX, rAX)
+ LW(pxepoff(SB), rAX)
PUSHR(rAX)
CALL16(spllo(SB))
@@ -230,8 +233,12 @@
CLR(rDX)
CLR(rDI)
CLR(rSI)
-_farret:
FARRET
+
+TEXT pxepseg(SB), $0
+ WORD $0
+TEXT pxepoff(SB), $0
+ WORD $0
#else /* PXE */
--- a/sys/src/boot/pc/mem.h
+++ b/sys/src/boot/pc/mem.h
@@ -13,62 +13,17 @@
#define PGSHIFT 12 /* log(BY2PG) */
#define PGROUND(s) (((s)+(BY2PG-1))&~(BY2PG-1))
-#define MAXMACH 1 /* max # cpus system can run */
-
/*
- * Time
- */
-#define HZ (100) /* clock frequency */
-#define MS2HZ (1000/HZ) /* millisec per clock tick */
-#define TK2SEC(t) ((t)/HZ) /* ticks to seconds */
-#define TK2MS(x) ((x)*(1000/HZ))
-#define MS2TK(t) ((((ulong)(t))*HZ)/1000) /* milliseconds to ticks */
-
-/*
* Fundamental addresses
*/
-#define IDTADDR 0x80000800 /* idt */
-#define APBOOTSTRAP 0x80001000 /* AP bootstrap code */
#define CONFADDR 0x80001200 /* info passed from boot loader */
-#define CPU0PDB 0x80002000 /* bootstrap processor PDB */
-#define CPU0PTE 0x80003000 /* bootstrap processor PTE's for 0-4MB */
-#define MACHADDR 0x80004000 /* as seen by current processor */
-#define CPU0MACH 0x80005000 /* Mach for bootstrap processor */
#define BIOSXCHG 0x80006000 /* To exchange data with the BIOS */
-#define MACHSIZE (BY2PG*8) /* stack size */
-/*
- * Address spaces
- *
- * Kernel is at 2GB-4GB
- */
-#define KZERO 0x80000000 /* base of kernel address space */
-#define KTZERO KZERO /* first address in kernel text */
-#define ROMBIOS (KZERO|0xF0000)
-
-/*
- * known 80386 segments (in GDT) and their selectors
- */
-#define NULLSEG 0 /* null segment */
-#define KDSEG 1 /* kernel data/stack */
-#define KESEG 2 /* kernel executable */
-#define UDSEG 3 /* user data/stack */
-#define UESEG 4 /* user executable */
-#define SYSGATE 5 /* system call gate */
-#define TSSSEG 6 /* task segment */
-
#define SELGDT (0<<3) /* selector is in gdt */
#define SELLDT (1<<3) /* selector is in ldt */
#define SELECTOR(i, t, p) (((i)<<3) | (t) | (p))
-#define NULLSEL SELECTOR(NULLSEG, SELGDT, 0)
-#define KESEL SELECTOR(KESEG, SELGDT, 0)
-#define KDSEL SELECTOR(KDSEG, SELGDT, 0)
-#define UESEL SELECTOR(UESEG, SELGDT, 3)
-#define UDSEL SELECTOR(UDSEG, SELGDT, 3)
-#define TSSSEL SELECTOR(TSSSEG, SELGDT, 0)
-
/*
* fields in segment descriptors
*/
@@ -89,26 +44,3 @@
#define SEGR (1<<9) /* readable (for code) */
#define SEGD (1<<22) /* default 1==32bit (for code) */
-/*
- * virtual MMU
- */
-#define PTEMAPMEM (1024*1024) /* ??? */
-#define SEGMAPSIZE 16 /* ??? */
-#define PTEPERTAB (PTEMAPMEM/BY2PG) /* ??? */
-#define PPN(x) ((x)&~(BY2PG-1))
-
-/*
- * physical MMU
- */
-#define PTEVALID (1<<0)
-#define PTEUNCACHED 0 /* everything is uncached */
-#define PTEWRITE (1<<1)
-#define PTERONLY (0<<1)
-#define PTEKERNEL (0<<2)
-#define PTEUSER (1<<2)
-#define PTESIZE (1<<7)
-
-/*
- * flag register bits that we care about
- */
-#define IFLAG 0x200
--- a/sys/src/boot/pc/pxe.c
+++ b/sys/src/boot/pc/pxe.c
@@ -57,6 +57,7 @@
char bootfile[128];
};
+int pxeinit(void);
int pxecall(int op, void *buf);
static void*
@@ -105,6 +106,17 @@
memmove(d, s, sizeof(d));
}
+void
+unload(void)
+{+ struct {+ uchar status[2];
+ uchar junk[10];
+ } buf;
+ puts(buf.status, 0);
+ pxecall(0x70, &buf);
+}
+
static int
getip(IP4 yip, IP4 sip, IP4 gip, char mac[16])
{@@ -153,7 +165,7 @@
static int
udpclose(void)
{- char status[2];
+ uchar status[2];
puts(status, 0);
return pxecall(0x31, status);
}
@@ -268,6 +280,7 @@
udpclose();
}
+
static int
tftpopen(Tftp *t, char *path, IP4 sip, IP4 dip, IP4 gip)
{@@ -311,6 +324,10 @@
void *f;
Tftp t;
+ if(pxeinit()){+ print("pxe init\r\n");+ halt();
+ }
if(getip(yip, sip, gip, mac)){ print("bad dhcp\r\n");halt();
--- a/sys/src/boot/pc/sub.c
+++ b/sys/src/boot/pc/sub.c
@@ -18,9 +18,18 @@
{uchar *d = dst;
uchar *s = src;
- while(n > 0){- *d++ = *s++;
- n--;
+ if(d < s){+ while(n > 0){+ *d++ = *s++;
+ n--;
+ }
+ } if(d > s){+ s += n;
+ d += n;
+ while(n > 0){+ *--d = *--s;
+ n--;
+ }
}
}
@@ -192,9 +201,9 @@
char*
bootkern(void *f)
{- uchar *e, *d;
+ uchar *e, *d, *t;
+ ulong n;
Exec ex;
- int n;
a20();
if(readn(f, &ex, sizeof(ex)) != sizeof(ex))
@@ -202,14 +211,25 @@
if(beswal(ex.magic) != I_MAGIC)
return "bad magic";
e = (uchar*)(beswal(ex.entry) & ~0xF0000000UL);
+
+ /*
+ * the kernels load addess (entry) might overlap
+ * with some bios memory (pxe) that is needed to load
+ * it. so we read it to this address and after
+ * we finished, move it to final location.
+ */
+ t = (uchar*)0x200000;
n = beswal(ex.text);
- if(readn(f, e, n) != n)
+ if(readn(f, t, n) != n)
goto Error;
- d = (uchar*)(((ulong)e + n + 0xFFF) & ~0xFFFUL);
+ d = t + ((uchar*)PGROUND((ulong)e + n) - e);
n = beswal(ex.data);
if(readn(f, d, n) != n)
goto Error;
close(f);
+ unload();
+ n = (d + n) - t;
+ memmove(e, t, n);
jump(e);
Error:
return "i/o error";
--
⑨