[SeaBIOS] [PATCH 10/10] memmap: Introduce SYMBOL() macro to access linker script symbols
Kevin O'Connor
kevin at koconnor.net
Fri Oct 9 19:53:38 CEST 2015
Use a macro to define and obtain the value of a symbol introduced by
the linker scripts (scripts/layoutrom.py).
Signed-off-by: Kevin O'Connor <kevin at koconnor.net>
---
src/biosvar.h | 6 +++---
src/fw/biostables.c | 10 +++++-----
src/fw/csm.c | 4 ++--
src/fw/shadow.c | 10 ++++------
src/malloc.c | 25 ++++++++++++-------------
src/memmap.h | 4 ++++
src/post.c | 35 ++++++++++++++++-------------------
7 files changed, 46 insertions(+), 48 deletions(-)
diff --git a/src/biosvar.h b/src/biosvar.h
index 3b40957..f61fb6a 100644
--- a/src/biosvar.h
+++ b/src/biosvar.h
@@ -8,6 +8,7 @@
#include "config.h" // SEG_BDA
#include "farptr.h" // GET_FARVAR
+#include "memmap.h" // SYMBOL
#include "std/bda.h" // struct bios_data_area_s
@@ -112,13 +113,12 @@ static inline u16 get_global_seg(void) {
* "Low" memory variables
****************************************************************/
-extern u8 _zonelow_seg, zonelow_base[];
-#define SEG_LOW ((u32)&_zonelow_seg)
+#define SEG_LOW SYMBOL(_zonelow_seg)
#if MODESEGMENT
#define GET_LOW(var) GET_FARVAR(SEG_LOW, (var))
#define SET_LOW(var, val) SET_FARVAR(SEG_LOW, (var), (val))
-#define LOWFLAT2LOW(var) ((typeof(var))((void*)(var) - (u32)zonelow_base))
+#define LOWFLAT2LOW(var) ((typeof(var))((void*)(var) - SYMBOL(zonelow_base)))
#else
#define GET_LOW(var) (var)
#define SET_LOW(var, val) do { (var) = (val); } while (0)
diff --git a/src/fw/biostables.c b/src/fw/biostables.c
index 71a1a0d..cc7a730 100644
--- a/src/fw/biostables.c
+++ b/src/fw/biostables.c
@@ -6,14 +6,15 @@
#include "byteorder.h" // le32_to_cpu
#include "config.h" // CONFIG_*
+#include "hw/pci.h" // pci_config_writeb
#include "malloc.h" // malloc_fseg
+#include "memmap.h" // SYMBOL
#include "output.h" // dprintf
-#include "hw/pci.h" // pci_config_writeb
+#include "romfile.h" // romfile_find
#include "std/acpi.h" // struct rsdp_descriptor
#include "std/mptable.h" // MPTABLE_SIGNATURE
#include "std/pirtable.h" // struct pir_header
#include "std/smbios.h" // struct smbios_entry_point
-#include "romfile.h"
#include "string.h" // memcpy
#include "util.h" // copy_table
#include "x86.h" // outb
@@ -122,9 +123,8 @@ copy_acpi_rsdp(void *pos)
void *find_acpi_rsdp(void)
{
- extern u8 zonefseg_start[], zonefseg_end[];
- unsigned long start = (unsigned long)zonefseg_start;
- unsigned long end = (unsigned long)zonefseg_end;
+ unsigned long start = SYMBOL(zonefseg_start);
+ unsigned long end = SYMBOL(zonefseg_end);
unsigned long pos;
for (pos = ALIGN(start, 0x10); pos <= ALIGN_DOWN(end, 0x10); pos += 0x10)
diff --git a/src/fw/csm.c b/src/fw/csm.c
index 0467560..c837d17 100644
--- a/src/fw/csm.c
+++ b/src/fw/csm.c
@@ -11,6 +11,7 @@
#include "hw/pci.h" // pci_probe_devices
#include "hw/pic.h" // pic_irqmask_read
#include "malloc.h" // csm_malloc_preinit
+#include "memmap.h" // SYMBOL
#include "output.h" // dprintf
#include "paravirt.h" // qemu_preinit
#include "stacks.h" // wait_threads
@@ -47,12 +48,11 @@ static void
csm_return(struct bregs *regs)
{
u32 rommax = rom_get_max();
- extern u8 final_readonly_start[];
dprintf(3, "handle_csm returning AX=%04x\n", regs->ax);
csm_compat_table.UmaAddress = rommax;
- csm_compat_table.UmaSize = (u32)final_readonly_start - rommax;
+ csm_compat_table.UmaSize = SYMBOL(final_readonly_start) - rommax;
PICMask = pic_irqmask_read();
__csm_return(regs);
diff --git a/src/fw/shadow.c b/src/fw/shadow.c
index 936ae28..ee87d36 100644
--- a/src/fw/shadow.c
+++ b/src/fw/shadow.c
@@ -53,9 +53,8 @@ __make_bios_writable_intel(u16 bdf, u32 pam0)
return;
// Copy bios.
- extern u8 code32flat_start[], code32flat_end[];
- memcpy(code32flat_start, code32flat_start + BIOS_SRC_OFFSET
- , code32flat_end - code32flat_start);
+ memcpy(VSYMBOL(code32flat_start), VSYMBOL(code32flat_start) + BIOS_SRC_OFFSET
+ , SYMBOL(code32flat_end) - SYMBOL(code32flat_start));
}
static void
@@ -165,7 +164,6 @@ qemu_prep_reset(void)
// QEMU doesn't map 0xc0000-0xfffff back to the original rom on a
// reset, so do that manually before invoking a hard reset.
make_bios_writable();
- extern u8 code32flat_start[], code32flat_end[];
- memcpy(code32flat_start, code32flat_start + BIOS_SRC_OFFSET
- , code32flat_end - code32flat_start);
+ memcpy(VSYMBOL(code32flat_start), VSYMBOL(code32flat_start) + BIOS_SRC_OFFSET
+ , SYMBOL(code32flat_end) - SYMBOL(code32flat_start));
}
diff --git a/src/malloc.c b/src/malloc.c
index 106c7ea..5113bb6 100644
--- a/src/malloc.c
+++ b/src/malloc.c
@@ -366,8 +366,7 @@ rom_get_max(void)
if (CONFIG_MALLOC_UPPERMEMORY)
return ALIGN_DOWN(RomBase->range_end - OPROM_HEADER_RESERVE
, OPTION_ROM_ALIGN);
- extern u8 final_readonly_start[];
- return (u32)final_readonly_start;
+ return SYMBOL(final_readonly_start);
}
// Return the end of the last deployed option rom.
@@ -385,8 +384,8 @@ rom_reserve(u32 size)
if (newend > rom_get_max())
return NULL;
if (CONFIG_MALLOC_UPPERMEMORY) {
- if (newend < (u32)zonelow_base)
- newend = (u32)zonelow_base;
+ if (newend < SYMBOL(zonelow_base))
+ newend = SYMBOL(zonelow_base);
RomBase->range_start = newend + OPROM_HEADER_RESERVE;
}
return (void*)RomEnd;
@@ -504,21 +503,21 @@ malloc_init(void)
}
// Initialize low-memory region
- extern u8 varlow_start[], varlow_end[], final_varlow_start[];
- memmove(final_varlow_start, varlow_start, varlow_end - varlow_start);
+ memmove(VSYMBOL(final_varlow_start), VSYMBOL(varlow_start)
+ , SYMBOL(varlow_end) - SYMBOL(varlow_start));
if (CONFIG_MALLOC_UPPERMEMORY) {
- alloc_add(&ZoneLow, (u32)zonelow_base + OPROM_HEADER_RESERVE
- , (u32)final_varlow_start);
+ alloc_add(&ZoneLow, SYMBOL(zonelow_base) + OPROM_HEADER_RESERVE
+ , SYMBOL(final_varlow_start));
RomBase = alloc_find_lowest(&ZoneLow);
} else {
- alloc_add(&ZoneLow, ALIGN_DOWN((u32)final_varlow_start, 1024)
- , (u32)final_varlow_start);
+ alloc_add(&ZoneLow, ALIGN_DOWN(SYMBOL(final_varlow_start), 1024)
+ , SYMBOL(final_varlow_start));
}
// Add space available in f-segment to ZoneFSeg
- extern u8 zonefseg_start[], zonefseg_end[];
- memset(zonefseg_start, 0, zonefseg_end - zonefseg_start);
- alloc_add(&ZoneFSeg, (u32)zonefseg_start, (u32)zonefseg_end);
+ memset(VSYMBOL(zonefseg_start), 0
+ , SYMBOL(zonefseg_end) - SYMBOL(zonefseg_start));
+ alloc_add(&ZoneFSeg, SYMBOL(zonefseg_start), SYMBOL(zonefseg_end));
calcRamSize();
}
diff --git a/src/memmap.h b/src/memmap.h
index 092e2ad..22bd4bc 100644
--- a/src/memmap.h
+++ b/src/memmap.h
@@ -14,4 +14,8 @@ static inline void *memremap(u32 addr, u32 len) {
return (void*)addr;
}
+// Return the value of a linker script symbol (see scripts/layoutrom.py)
+#define SYMBOL(SYM) ({ extern char SYM; (u32)&SYM; })
+#define VSYMBOL(SYM) ((void*)SYMBOL(SYM))
+
#endif // memmap.h
diff --git a/src/post.c b/src/post.c
index 89e6eff..49c22b8 100644
--- a/src/post.c
+++ b/src/post.c
@@ -25,6 +25,7 @@
#include "hw/virtio-blk.h" // virtio_blk_setup
#include "hw/virtio-scsi.h" // virtio_scsi_setup
#include "malloc.h" // malloc_init
+#include "memmap.h" // SYMBOL
#include "output.h" // dprintf
#include "string.h" // memset
#include "util.h" // kbd_init
@@ -89,9 +90,8 @@ bda_init(void)
int esize = EBDA_SIZE_START;
u16 ebda_seg = EBDA_SEGMENT_START;
- extern u8 final_varlow_start[];
if (!CONFIG_MALLOC_UPPERMEMORY)
- ebda_seg = FLATPTR_TO_SEG(ALIGN_DOWN((u32)final_varlow_start, 1024)
+ ebda_seg = FLATPTR_TO_SEG(ALIGN_DOWN(SYMBOL(final_varlow_start), 1024)
- EBDA_SIZE_START*1024);
SET_BDA(ebda_seg, ebda_seg);
@@ -105,7 +105,7 @@ bda_init(void)
e820_add((u32)ebda, BUILD_LOWRAM_END-(u32)ebda, E820_RESERVED);
// Init extra stack
- StackPos = (void*)(&ExtraStack[BUILD_EXTRA_STACK_SIZE] - zonelow_base);
+ StackPos = &ExtraStack[BUILD_EXTRA_STACK_SIZE] - SYMBOL(zonelow_base);
}
void
@@ -276,30 +276,27 @@ reloc_preinit(void *f, void *arg)
void (*func)(void *) __noreturn = f;
if (!CONFIG_RELOCATE_INIT)
func(arg);
- // Symbols populated by the build.
- extern u8 code32flat_start[];
- extern u8 _reloc_min_align;
- extern u32 _reloc_abs_start[], _reloc_abs_end[];
- extern u32 _reloc_rel_start[], _reloc_rel_end[];
- extern u32 _reloc_init_start[], _reloc_init_end[];
- extern u8 code32init_start[], code32init_end[];
// Allocate space for init code.
- u32 initsize = code32init_end - code32init_start;
- u32 codealign = (u32)&_reloc_min_align;
+ u32 initsize = SYMBOL(code32init_end) - SYMBOL(code32init_start);
+ u32 codealign = SYMBOL(_reloc_min_align);
void *codedest = memalign_tmp(codealign, initsize);
+ void *codesrc = VSYMBOL(code32init_start);
if (!codedest)
panic("No space for init relocation.\n");
// Copy code and update relocs (init absolute, init relative, and runtime)
dprintf(1, "Relocating init from %p to %p (size %d)\n"
- , code32init_start, codedest, initsize);
- s32 delta = codedest - (void*)code32init_start;
- memcpy(codedest, code32init_start, initsize);
- updateRelocs(codedest, _reloc_abs_start, _reloc_abs_end, delta);
- updateRelocs(codedest, _reloc_rel_start, _reloc_rel_end, -delta);
- updateRelocs(code32flat_start, _reloc_init_start, _reloc_init_end, delta);
- if (f >= (void*)code32init_start && f < (void*)code32init_end)
+ , codesrc, codedest, initsize);
+ s32 delta = codedest - codesrc;
+ memcpy(codedest, codesrc, initsize);
+ updateRelocs(codedest, VSYMBOL(_reloc_abs_start), VSYMBOL(_reloc_abs_end)
+ , delta);
+ updateRelocs(codedest, VSYMBOL(_reloc_rel_start), VSYMBOL(_reloc_rel_end)
+ , -delta);
+ updateRelocs(VSYMBOL(code32flat_start), VSYMBOL(_reloc_init_start)
+ , VSYMBOL(_reloc_init_end), delta);
+ if (f >= codesrc && f < VSYMBOL(code32init_end))
func = f + delta;
// Call function in relocated code.
--
2.4.3
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