From f6d4a4415928ffca69eb0c498af777d74f4fc303 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Mon, 19 Jul 2010 16:29:24 -0700 Subject: [PATCH] dos: add memcpy_from_sl() and use it where appropriate Add memcpy_from_sl() and use it to handle pointers into the payload section. Signed-off-by: H. Peter Anvin --- dos/getsetsl.c | 17 +++++++++++++ dos/syslinux.c | 68 +++++++++++++++++++++++-------------------------- libinstaller/syslxint.h | 2 ++ 3 files changed, 51 insertions(+), 36 deletions(-) diff --git a/dos/getsetsl.c b/dos/getsetsl.c index 5c1dbbd..67e954d 100644 --- a/dos/getsetsl.c +++ b/dos/getsetsl.c @@ -98,3 +98,20 @@ void memcpy_to_sl(void *dst, const void *src, size_t len) : "r" (seg) : "memory"); } + +void memcpy_from_sl(void *dst, const void *src, size_t len) +{ + uint16_t seg; + uint16_t off; + + seg = ds() + ((size_t)src >> 4); + off = (size_t)src & 15; + + asm volatile("pushw %%ds ; " + "movw %3,%%ds ; " + "rep ; movsb ; " + "popw %%ds" + : "+D" (dst), "+S" (off), "+c" (len) + : "r" (seg) + : "memory"); +} diff --git a/dos/syslinux.c b/dos/syslinux.c index 744ec36..c935f8e 100755 --- a/dos/syslinux.c +++ b/dos/syslinux.c @@ -1,7 +1,7 @@ /* ----------------------------------------------------------------------- * * * Copyright 1998-2008 H. Peter Anvin - All Rights Reserved - * Copyright 2009 Intel Corporation; author: H. Peter Anvin + * Copyright 2009-2010 Intel Corporation; author: H. Peter Anvin * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -30,6 +30,7 @@ #include "setadv.h" #include "sysexits.h" #include "syslxopt.h" +#include "syslxint.h" const char *program = "syslinux"; /* Name of program */ uint16_t dos_version; @@ -119,11 +120,9 @@ int rename(const char *oldname, const char *newname) return 0; } -extern const char __payload_sseg[]; -uint16_t ldlinux_seg; - ssize_t write_ldlinux(int fd) { + uint16_t ldlinux_seg = ((size_t)syslinux_ldlinux >> 4) + ds(); uint32_t offset = 0; uint16_t rv; uint8_t err; @@ -136,8 +135,8 @@ ssize_t write_ldlinux(int fd) "movw %6,%%ds ; " "int $0x21 ; " "popw %%ds ; " "setc %0":"=bcdm" (err), "=a"(rv) - :"a"(0x4000), "b"(fd), "c"(chunk), "d"(offset & 15), - "SD"((uint16_t) (ldlinux_seg + (offset >> 4)))); + :"a"(0x4000), "b"(fd), "c"(chunk), "d" (offset & 15), + "SD" ((uint16_t)(ldlinux_seg + (offset >> 4)))); if (err || rv == 0) die("file write error"); offset += rv; @@ -178,7 +177,7 @@ uint16_t data_segment(void) void write_device(int drive, const void *buf, size_t nsecs, unsigned int sector) { - uint16_t errnum; + uint16_t errnum = 0x0001; struct diskio dio; dprintf("write_device(%d,%p,%u,%u)\n", drive, buf, nsecs, sector); @@ -187,14 +186,17 @@ void write_device(int drive, const void *buf, size_t nsecs, unsigned int sector) dio.sectors = nsecs; dio.bufoffs = (uintptr_t) buf; dio.bufseg = data_segment(); - - /* Try FAT32-aware system call first */ - asm volatile("int $0x21 ; jc 1f ; xorw %0,%0\n" - "1:" - : "=a" (errnum) - : "a" (0x7305), "b" (&dio), "c" (-1), "d" (drive), - "S" (1), "m" (dio) - : "memory"); + + if (dos_version >= 0x070a) { + /* Try FAT32-aware system call first */ + asm volatile("int $0x21 ; jc 1f ; xorw %0,%0\n" + "1:" + : "=a" (errnum) + : "a" (0x7305), "b" (&dio), "c" (-1), "d" (drive), + "S" (1), "m" (dio) + : "memory"); + dprintf(" rv(7305) = %04x", errnum); + } /* If not supported, try the legacy system call (int2526.S) */ if (errnum == 0x0001) @@ -206,9 +208,9 @@ void write_device(int drive, const void *buf, size_t nsecs, unsigned int sector) } } -void read_device(int drive, const void *buf, size_t nsecs, unsigned int sector) +void read_device(int drive, void *buf, size_t nsecs, unsigned int sector) { - uint16_t errnum; + uint16_t errnum = 0x0001; struct diskio dio; dprintf("read_device(%d,%p,%u,%u)\n", drive, buf, nsecs, sector); @@ -217,13 +219,16 @@ void read_device(int drive, const void *buf, size_t nsecs, unsigned int sector) dio.sectors = nsecs; dio.bufoffs = (uintptr_t) buf; dio.bufseg = data_segment(); - - /* Try FAT32-aware system call first */ - asm volatile("int $0x21 ; jc 1f ; xorw %0,%0\n" - "1:" - : "=a" (errnum) - : "a" (0x7305), "b" (&dio), "c" (-1), "d" (drive), - "S" (0), "m" (dio)); + + if (dos_version >= 0x070a) { + /* Try FAT32-aware system call first */ + asm volatile("int $0x21 ; jc 1f ; xorw %0,%0\n" + "1:" + : "=a" (errnum) + : "a" (0x7305), "b" (&dio), "c" (-1), "d" (drive), + "S" (0), "m" (dio)); + dprintf(" rv(7305) = %04x", errnum); + } /* If not supported, try the legacy system call (int2526.S) */ if (errnum == 0x0001) @@ -600,9 +605,6 @@ int main(int argc, char *argv[]) int raid_mode = 0; int patch_sectors; - ldlinux_seg = (size_t) __payload_sseg + data_segment(); -printf("SHAO seg: 0x%04x\n", ldlinux_seg); - dprintf("argv = %p\n", argv); for (i = 0; i <= argc; i++) dprintf("argv[%d] = %p = \"%s\"\n", i, argv[i], argv[i]); @@ -758,7 +760,6 @@ printf("SHAO seg: 0x%04x\n", ldlinux_seg); } } -printf("Foo: %p\n", syslinux_ldlinux); /* * Patch ldlinux.sys and the boot sector */ @@ -770,14 +771,9 @@ printf("Foo: %p\n", syslinux_ldlinux); */ /* lock_device(3); -- doesn't seem to be needed */ for (i = 0; i < patch_sectors; i++) { - uint16_t si, di, cx; - si = 0; - di = (size_t) sectbuf; - cx = SECTOR_SIZE >> 2; - asm volatile ("movw %3,%%fs ; fs ; rep ; movsl":"+S" (si), "+D"(di), - "+c"(cx) - :"abd"((uint16_t) - (ldlinux_seg + (i << (SECTOR_SHIFT - 4))))); + unsigned char *p = syslinux_ldlinux; + memcpy_from_sl(sectbuf, p, SECTOR_SIZE); + p += SECTOR_SIZE; write_device(dev_fd, sectbuf, 1, sectors[i]); } diff --git a/libinstaller/syslxint.h b/libinstaller/syslxint.h index b8e872a..14a7fc2 100644 --- a/libinstaller/syslxint.h +++ b/libinstaller/syslxint.h @@ -137,6 +137,7 @@ void set_16_sl(uint16_t * p, uint16_t v); void set_32_sl(uint32_t * p, uint32_t v); void set_64_sl(uint64_t * p, uint64_t v); void memcpy_to_sl(void *dst, const void *src, size_t len); +void memcpy_from_sl(void *dst, const void *src, size_t len); #else @@ -150,6 +151,7 @@ void memcpy_to_sl(void *dst, const void *src, size_t len); #define set_32_sl(x,y) set_32(x,y) #define set_64_sl(x,y) set_64(x,y) #define memcpy_to_sl(d,s,l) memcpy(d,s,l) +#define memcpy_from_sl(d,s,l) memcpy(d,s,l) #endif -- 2.7.4