[syslinux:elflink] execute(): move chainbooting code to its own file
syslinux-bot for H. Peter Anvin
hpa at zytor.com
Thu Jun 7 15:27:08 PDT 2012
Commit-ID: 83f4c75f69986637ae653cd94a37329f3841f65a
Gitweb: http://www.syslinux.org/commit/83f4c75f69986637ae653cd94a37329f3841f65a
Author: H. Peter Anvin <hpa at zytor.com>
AuthorDate: Thu, 7 Jun 2012 15:23:46 -0700
Committer: H. Peter Anvin <hpa at zytor.com>
CommitDate: Thu, 7 Jun 2012 15:23:46 -0700
execute(): move chainbooting code to its own file
To improve readability, move chainbooting to its own source file.
Signed-off-by: H. Peter Anvin <hpa at zytor.com>
---
com32/elflink/ldlinux/Makefile | 2 +-
com32/elflink/ldlinux/chainboot.c | 175 +++++++++++++++++++++++++++++++++++++
com32/elflink/ldlinux/execute.c | 137 +----------------------------
com32/include/menu.h | 3 +
4 files changed, 180 insertions(+), 137 deletions(-)
diff --git a/com32/elflink/ldlinux/Makefile b/com32/elflink/ldlinux/Makefile
index 75c618f..dc48ca9 100644
--- a/com32/elflink/ldlinux/Makefile
+++ b/com32/elflink/ldlinux/Makefile
@@ -20,7 +20,7 @@ LIBS = --whole-archive $(com32)/lib/libcom32min.a
all: ldlinux.c32 ldlinux_lnx.a
ldlinux.c32 : ldlinux.o cli.o readconfig.o refstr.o colors.o getadv.o \
- adv.o execute.o kernel.o get_key.o \
+ adv.o execute.o chainboot.o kernel.o get_key.o \
advwrite.o setadv.o eprintf.o loadhigh.o
$(LD) $(LDFLAGS) -o $@ $^ $(LIBS)
diff --git a/com32/elflink/ldlinux/chainboot.c b/com32/elflink/ldlinux/chainboot.c
new file mode 100644
index 0000000..28f3280
--- /dev/null
+++ b/com32/elflink/ldlinux/chainboot.c
@@ -0,0 +1,175 @@
+/* ----------------------------------------------------------------------- *
+ *
+ * Copyright 2012 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
+ * the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston MA 02110-1301, USA; either version 2 of the License, or
+ * (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * chainbooting - replace the current bootloader completely. This
+ * is BIOS-specific.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <dprintf.h>
+
+#include <com32.h>
+#include <sys/exec.h>
+#include <sys/io.h>
+#include "core.h"
+#include "menu.h"
+#include "fs.h"
+#include "config.h"
+#include "localboot.h"
+#include "bios.h"
+
+#include <syslinux/bootrm.h>
+#include <syslinux/movebits.h>
+#include <syslinux/config.h>
+
+void chainboot_file(const char *file, enum kernel_type type)
+{
+ uint8_t keeppxe = 0;
+ const union syslinux_derivative_info *sdi;
+ struct syslinux_rm_regs regs;
+ struct syslinux_movelist *fraglist = NULL;
+ struct syslinux_memmap *mmap = NULL;
+ struct com32_filedata fd;
+ unsigned int free_mem, new_free_mem;
+ unsigned int edx, esi, bx;
+ com32sys_t reg;
+ char *stack;
+ void *buf;
+ int rv, max, size;
+
+ max = 0xA0000; /* Maximum load */
+ buf = malloc(max);
+ if (!buf)
+ goto bail;
+
+ rv = open_file(file, &fd);
+ if (rv == -1) {
+ free(buf);
+ goto bail;
+ }
+
+ reg.eax.l = max;
+ reg.ebx.l = 0;
+ reg.edx.w[0] = 0;
+ reg.edi.l = (uint32_t)buf;
+ reg.ebp.l = -1; /* XXX: limit? */
+ reg.esi.w[0] = rv;
+
+ pm_load_high(®);
+
+ size = reg.edi.l - (unsigned long)buf;
+ if (size > 0xA0000 - 0x7C00) {
+ printf("Too large for a boostrap (need LINUX instead of KERNEL?)\n");
+ goto boot_bail;
+ }
+
+ esi = 0;
+ bx = 0;
+
+ sdi = syslinux_derivative_info();
+ edx = sdi->rr.r.edx.b[0];
+
+ memset(®s, 0, sizeof(regs));
+
+ if (sdi->c.filesystem == SYSLINUX_FS_SYSLINUX ||
+ sdi->c.filesystem == SYSLINUX_FS_EXTLINUX) {
+ memcpy((void *)0x800 - 18, sdi->r.esbx, 16);
+
+ /* DS:SI points to partition info */
+ esi = 0x800 - 18;
+ }
+
+ /*
+ * For a BSS boot sector we have to transfer the
+ * superblock.
+ */
+ if (sdi->c.filesystem == SYSLINUX_FS_SYSLINUX &&
+ type == KT_BSS && vfat_copy_superblock(buf))
+ goto boot_bail;
+
+ /*
+ * Set up initial stack frame (not used by PXE if
+ * keeppxe is set - we use the PXE stack then.)
+ */
+ if (sdi->c.filesystem == SYSLINUX_FS_PXELINUX) {
+ keeppxe = 0x03; /* Chainloading + keep PXE */
+ stack = (char *)sdi->r.fssi;
+
+ /*
+ * Restore DS, EDX and ESI to the true initial
+ * values.
+ */
+ bx = *(uint16_t *)&stack[6];
+ edx = *(uint32_t *)&stack[28];
+ esi = *(uint32_t *)&stack[12];
+
+ /* Reset stack to PXE original */
+ regs.es = regs.ss = sdi->rr.r.fs;
+ regs.esp.w[0] = sdi->rr.r.esi.w[0] + 44;
+ } else {
+ char *esdi = (char *)sdi->disk.esdi_ptr;
+
+ /*
+ * StackBuf is guaranteed to have 44 bytes
+ * free immediately above it, and will not
+ * interfere with our existing stack.
+ */
+ stack = StackBuf;
+ memset(stack, 0, 44);
+
+ regs.esp.w[0] = (uint16_t)(unsigned long)stack + 44;
+
+ /*
+ * DON'T DO THIS FOR PXELINUX...
+ * For PXE, ES:BX -> PXENV+, and this would
+ * corrupt that use.
+ *
+ * Restore ES:DI -> $PnP (if we were ourselves
+ * called that way...)
+ */
+
+ /* New DI */
+ *(uint16_t *)&stack[8] = *(uint16_t *)&esdi[0];
+
+ /* New ES */
+ *(uint16_t *)&stack[4] = *(uint16_t *)&esdi[2];
+
+ }
+
+ *(uint32_t *)&stack[28] = edx; /* New EDX */
+ *(uint32_t *)&stack[12] = esi; /* New ESI */
+ *(uint16_t *)&stack[6] = bx; /* New DS */
+
+ regs.ip = 0x7c00;
+ regs.esi.l = esi;
+ regs.edx.l = edx;
+
+ free_mem = *(volatile unsigned int *)BIOS_fbm;
+ free_mem <<= 10;
+ new_free_mem = free_mem - (0x7c00 + size);
+
+ mmap = syslinux_memory_map();
+ if (!mmap)
+ goto boot_bail;
+
+ if (!syslinux_add_movelist(&fraglist, 0x7c00, (addr_t)buf, size))
+ syslinux_shuffle_boot_rm(fraglist, mmap, keeppxe, ®s);
+
+ free(mmap);
+boot_bail:
+ free(buf);
+bail:
+ return;
+}
diff --git a/com32/elflink/ldlinux/execute.c b/com32/elflink/ldlinux/execute.c
index 5e47a62..97e5116 100644
--- a/com32/elflink/ldlinux/execute.c
+++ b/com32/elflink/ldlinux/execute.c
@@ -53,7 +53,6 @@ void execute(const char *cmdline, enum kernel_type type)
const char *kernel, *args;
com32sys_t ireg;
char *q;
- uint8_t keeppxe = 0;
memset(&ireg, 0, sizeof ireg);
@@ -109,147 +108,13 @@ void execute(const char *cmdline, enum kernel_type type)
} else if (type == KT_LOCALBOOT) {
local_boot(strtoul(kernel, NULL, 0));
} else if (type == KT_PXE || type == KT_BSS || type == KT_BOOT) {
- const union syslinux_derivative_info *sdi;
- struct syslinux_rm_regs regs;
- struct syslinux_movelist *fraglist = NULL;
- struct syslinux_memmap *mmap = NULL;
- struct com32_filedata fd;
- unsigned int free_mem, new_free_mem;
- unsigned int edx, esi, bx;
- com32sys_t reg;
- char *stack;
- void *buf;
- int rv, max, size;
-
- max = 0xA0000; /* Maximum load */
- buf = malloc(max);
- if (!buf)
- goto bail;
-
- rv = open_file(kernel, &fd);
- if (rv == -1) {
- free(buf);
- goto bail;
- }
-
- reg.eax.l = max;
- reg.ebx.l = 0;
- reg.edx.w[0] = 0;
- reg.edi.l = (uint32_t)buf;
- reg.ebp.l = -1; /* XXX: limit? */
- reg.esi.w[0] = rv;
-
- pm_load_high(®);
-
- size = reg.edi.l - (unsigned long)buf;
- if (size > 0xA0000 - 0x7C00) {
- printf("Too large for a boostrap (need LINUX instead of KERNEL?)\n");
- goto boot_bail;
- }
-
- esi = 0;
- bx = 0;
-
- sdi = syslinux_derivative_info();
- edx = sdi->rr.r.edx.b[0];
-
- memset(®s, 0, sizeof(regs));
-
- if (sdi->c.filesystem == SYSLINUX_FS_SYSLINUX ||
- sdi->c.filesystem == SYSLINUX_FS_EXTLINUX) {
- memcpy((void *)0x800 - 18, sdi->r.esbx, 16);
-
- /* DS:SI points to partition info */
- esi = 0x800 - 18;
- }
-
- /*
- * For a BSS boot sector we have to transfer the
- * superblock.
- */
- if (sdi->c.filesystem == SYSLINUX_FS_SYSLINUX &&
- type == KT_BSS && vfat_copy_superblock(buf))
- goto boot_bail;
-
- /*
- * Set up initial stack frame (not used by PXE if
- * keeppxe is set - we use the PXE stack then.)
- */
- if (sdi->c.filesystem == SYSLINUX_FS_PXELINUX) {
- keeppxe = 0x03; /* Chainloading + keep PXE */
- stack = (char *)sdi->r.fssi;
-
- /*
- * Restore DS, EDX and ESI to the true initial
- * values.
- */
- bx = *(uint16_t *)&stack[6];
- edx = *(uint32_t *)&stack[28];
- esi = *(uint32_t *)&stack[12];
-
- /* Reset stack to PXE original */
- regs.es = regs.ss = sdi->rr.r.fs;
- regs.esp.w[0] = sdi->rr.r.esi.w[0] + 44;
- } else {
- char *esdi = (char *)sdi->disk.esdi_ptr;
-
- /*
- * StackBuf is guaranteed to have 44 bytes
- * free immediately above it, and will not
- * interfere with our existing stack.
- */
- stack = StackBuf;
- memset(stack, 0, 44);
-
- regs.esp.w[0] = (uint16_t)(unsigned long)stack + 44;
-
- /*
- * DON'T DO THIS FOR PXELINUX...
- * For PXE, ES:BX -> PXENV+, and this would
- * corrupt that use.
- *
- * Restore ES:DI -> $PnP (if we were ourselves
- * called that way...)
- */
-
- /* New DI */
- *(uint16_t *)&stack[8] = *(uint16_t *)&esdi[0];
-
- /* New ES */
- *(uint16_t *)&stack[4] = *(uint16_t *)&esdi[2];
-
- }
-
- *(uint32_t *)&stack[28] = edx; /* New EDX */
- *(uint32_t *)&stack[12] = esi; /* New ESI */
- *(uint16_t *)&stack[6] = bx; /* New DS */
-
- regs.ip = 0x7c00;
- regs.esi.l = esi;
- regs.edx.l = edx;
-
- free_mem = *(volatile unsigned int *)BIOS_fbm;
- free_mem <<= 10;
- new_free_mem = free_mem - (0x7c00 + size);
-
- mmap = syslinux_memory_map();
- if (!mmap)
- goto boot_bail;
-
- if (!syslinux_add_movelist(&fraglist, 0x7c00,
- (addr_t)buf, size))
- syslinux_shuffle_boot_rm(fraglist, mmap,
- keeppxe, ®s);
- free(mmap);
-boot_bail:
- free(buf);
+ chainboot_file(kernel, type);
} else {
/* Need add one item for kernel load, as we don't use
* the assembly runkernel.inc any more */
new_linux_kernel((char *)kernel, (char *)cmdline);
}
-bail:
lfree((void *)kernel);
/* If this returns, something went bad; return to menu */
diff --git a/com32/include/menu.h b/com32/include/menu.h
index ba6b9ce..be2eaeb 100644
--- a/com32/include/menu.h
+++ b/com32/include/menu.h
@@ -234,4 +234,7 @@ void execute(const char *cmdline, enum kernel_type type);
/* drain.c */
void drain_keyboard(void);
+/* chainboot.c */
+void chainboot_file(const char *file, enum kernel_type type);
+
#endif /* MENU_H */
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