:: commit 9f74289bd38415d9360f08690fce5f1bf992a694
stivale2: Introduce fully virtual kernel mappings
diff --git a/stage23/lib/elf.c b/stage23/lib/elf.c
index 360b40c2..80af3823 100644
--- a/stage23/lib/elf.c
+++ b/stage23/lib/elf.c
@@ -430,7 +430,7 @@ static void elf64_get_ranges(uint8_t *elf, uint64_t slide, bool use_paddr, struc
*_ranges = ranges;
}
-int elf64_load(uint8_t *elf, uint64_t *entry_point, uint64_t *top, uint64_t *_slide, uint32_t alloc_type, bool kaslr, bool use_paddr, struct elf_range **ranges, uint64_t *ranges_count) {
+int elf64_load(uint8_t *elf, uint64_t *entry_point, uint64_t *top, uint64_t *_slide, uint32_t alloc_type, bool kaslr, bool use_paddr, struct elf_range **ranges, uint64_t *ranges_count, bool fully_virtual, uint64_t *physical_base, uint64_t *virtual_base) {
struct elf64_hdr hdr;
memcpy(&hdr, elf + (0), sizeof(struct elf64_hdr));
@@ -457,6 +457,41 @@ int elf64_load(uint8_t *elf, uint64_t *entry_point, uint64_t *top, uint64_t *_sl
uint64_t max_align = elf64_max_align(elf);
+ uint64_t base_load_addr;
+
+ if (fully_virtual) {
+ simulation = false;
+
+ uint64_t min_vaddr = (uint64_t)-1;
+ uint64_t max_vaddr = 0;
+ for (uint16_t i = 0; i < hdr.ph_num; i++) {
+ struct elf64_phdr phdr;
+ memcpy(&phdr, elf + (hdr.phoff + i * sizeof(struct elf64_phdr)),
+ sizeof(struct elf64_phdr));
+
+ if (phdr.p_type != PT_LOAD)
+ continue;
+
+ if (phdr.p_type != PT_LOAD)
+ continue;
+
+ if (phdr.p_vaddr < min_vaddr) {
+ min_vaddr = phdr.p_vaddr;
+ }
+
+ if (phdr.p_vaddr + phdr.p_memsz > max_vaddr) {
+ max_vaddr = phdr.p_vaddr + phdr.p_memsz;
+ }
+ }
+
+ uint64_t image_size = max_vaddr - min_vaddr;
+
+ base_load_addr = (uintptr_t)ext_mem_alloc_type_aligned(image_size, alloc_type, max_align);
+
+ *physical_base = base_load_addr;
+ *virtual_base = min_vaddr;
+ }
+
if (!elf64_is_relocatable(elf, &hdr)) {
simulation = false;
goto final;
@@ -490,6 +525,10 @@ final:
if (load_addr & ((uint64_t)1 << 63)) {
higher_half = true;
load_addr -= FIXED_HIGHER_HALF_OFFSET_64;
+
+ if (fully_virtual) {
+ load_addr += base_load_addr;
+ }
}
}
@@ -497,7 +536,9 @@ final:
panic("elf: Higher half executable trying to load too high");
}
- load_addr += slide;
+ if (!fully_virtual) {
+ load_addr += slide;
+ }
uint64_t this_top = load_addr + phdr.p_memsz;
@@ -522,7 +563,8 @@ final:
mem_size = phdr.p_memsz;
}
- if (!memmap_alloc_range((size_t)mem_base, (size_t)mem_size, alloc_type, true, false, simulation, false)) {
+ if (!fully_virtual &&
+ !memmap_alloc_range((size_t)mem_base, (size_t)mem_size, alloc_type, true, false, simulation, false)) {
if (++try_count == max_simulated_tries || simulation == false) {
panic("elf: Failed to allocate necessary memory ranges");
}
diff --git a/stage23/lib/elf.h b/stage23/lib/elf.h
index 2d300f11..8db57f91 100644
--- a/stage23/lib/elf.h
+++ b/stage23/lib/elf.h
@@ -27,7 +27,7 @@ struct elf_section_hdr_info {
int elf_bits(uint8_t *elf);
-int elf64_load(uint8_t *elf, uint64_t *entry_point, uint64_t *top, uint64_t *_slide, uint32_t alloc_type, bool kaslr, bool use_paddr, struct elf_range **ranges, uint64_t *ranges_count);
+int elf64_load(uint8_t *elf, uint64_t *entry_point, uint64_t *top, uint64_t *_slide, uint32_t alloc_type, bool kaslr, bool use_paddr, struct elf_range **ranges, uint64_t *ranges_count, bool fully_virtual, uint64_t *physical_base, uint64_t *virtual_base);
int elf64_load_section(uint8_t *elf, void *buffer, const char *name, size_t limit, uint64_t slide);
struct elf_section_hdr_info* elf64_section_hdr_info(uint8_t *elf);
diff --git a/stage23/mm/pmm.h b/stage23/mm/pmm.h
index fce753e6..5426e334 100644
--- a/stage23/mm/pmm.h
+++ b/stage23/mm/pmm.h
@@ -46,6 +46,7 @@ void pmm_randomise_memory(void);
void *ext_mem_alloc(size_t count);
void *ext_mem_alloc_type(size_t count, uint32_t type);
+void *ext_mem_alloc_type_aligned(size_t count, uint32_t type, size_t alignment);
void *conv_mem_alloc(size_t count);
diff --git a/stage23/mm/pmm.s2.c b/stage23/mm/pmm.s2.c
index 984d68f6..f023c7f2 100644
--- a/stage23/mm/pmm.s2.c
+++ b/stage23/mm/pmm.s2.c
@@ -574,9 +574,13 @@ void *ext_mem_alloc(size_t count) {
return ext_mem_alloc_type(count, MEMMAP_BOOTLOADER_RECLAIMABLE);
}
-// Allocate memory top down, hopefully without bumping into kernel or modules
void *ext_mem_alloc_type(size_t count, uint32_t type) {
- count = ALIGN_UP(count, 4096);
+ return ext_mem_alloc_type_aligned(count, type, 4096);
+}
+
+// Allocate memory top down, hopefully without bumping into kernel or modules
+void *ext_mem_alloc_type_aligned(size_t count, uint32_t type, size_t alignment) {
+ count = ALIGN_UP(count, alignment);
if (allocations_disallowed)
panic("Memory allocations disallowed");
@@ -595,7 +599,7 @@ void *ext_mem_alloc_type(size_t count, uint32_t type) {
continue;
}
- int64_t alloc_base = ALIGN_DOWN(entry_top - (int64_t)count, 4096);
+ int64_t alloc_base = ALIGN_DOWN(entry_top - (int64_t)count, alignment);
// This entry is too small for us.
if (alloc_base < entry_base)
diff --git a/stage23/protos/multiboot1.c b/stage23/protos/multiboot1.c
index ce3582e2..3a67d274 100644
--- a/stage23/protos/multiboot1.c
+++ b/stage23/protos/multiboot1.c
@@ -104,7 +104,7 @@ void multiboot1_load(char *config, char *cmdline) {
break;
case 64: {
uint64_t e, t;
- if (elf64_load(kernel, &e, &t, NULL, MEMMAP_KERNEL_AND_MODULES, false, true, NULL, NULL))
+ if (elf64_load(kernel, &e, &t, NULL, MEMMAP_KERNEL_AND_MODULES, false, true, NULL, NULL, false, NULL, NULL))
panic("multiboot1: ELF64 load failure");
entry_point = e;
kernel_top = t;
diff --git a/stage23/protos/multiboot2.c b/stage23/protos/multiboot2.c
index 3b0d29ec..efcc8f74 100644
--- a/stage23/protos/multiboot2.c
+++ b/stage23/protos/multiboot2.c
@@ -225,7 +225,7 @@ void multiboot2_load(char *config, char* cmdline) {
break;
case 64: {
- if (elf64_load(kernel, &e, &t, NULL, MEMMAP_KERNEL_AND_MODULES, false, true, NULL, NULL))
+ if (elf64_load(kernel, &e, &t, NULL, MEMMAP_KERNEL_AND_MODULES, false, true, NULL, NULL, false, NULL, NULL))
panic("multiboot2: ELF64 load failure");
break;
diff --git a/stage23/protos/stivale.c b/stage23/protos/stivale.c
index a29ca68b..c302401d 100644
--- a/stage23/protos/stivale.c
+++ b/stage23/protos/stivale.c
@@ -127,7 +127,7 @@ void stivale_load(char *config, char *cmdline) {
if (!loaded_by_anchor) {
if (elf64_load(kernel, &entry_point, NULL, &slide,
STIVALE_MMAP_KERNEL_AND_MODULES, kaslr, false,
- NULL, NULL))
+ NULL, NULL, false, NULL, NULL))
panic("stivale: ELF64 load failure");
ret = elf64_load_section(kernel, &stivale_hdr, ".stivalehdr",
@@ -300,7 +300,7 @@ void stivale_load(char *config, char *cmdline) {
pagemap_t pagemap = {0};
if (bits == 64)
- pagemap = stivale_build_pagemap(want_5lv, false, NULL, 0);
+ pagemap = stivale_build_pagemap(want_5lv, false, NULL, 0, false, 0);
// Reserve 32K at 0x70000
memmap_alloc_range(0x70000, 0x8000, MEMMAP_USABLE, true, true, false, false);
@@ -324,7 +324,8 @@ void stivale_load(char *config, char *cmdline) {
stivale_hdr.stack, false);
}
-pagemap_t stivale_build_pagemap(bool level5pg, bool unmap_null, struct elf_range *ranges, size_t ranges_count) {
+pagemap_t stivale_build_pagemap(bool level5pg, bool unmap_null, struct elf_range *ranges, size_t ranges_count,
+ bool want_fully_virtual, uint64_t physical_base) {
pagemap_t pagemap = new_pagemap(level5pg ? 5 : 4);
uint64_t higher_half_base = level5pg ? 0xff00000000000000 : 0xffff800000000000;
@@ -336,10 +337,14 @@ pagemap_t stivale_build_pagemap(bool level5pg, bool unmap_null, struct elf_range
} else {
for (size_t i = 0; i < ranges_count; i++) {
uint64_t virt = ranges[i].base;
- uint64_t phys = virt;
-
- if (phys & ((uint64_t)1 << 63)) {
- phys -= FIXED_HIGHER_HALF_OFFSET_64;
+ uint64_t phys;
+
+ if (virt & ((uint64_t)1 << 63)) {
+ if (want_fully_virtual) {
+ phys = physical_base + (virt - FIXED_HIGHER_HALF_OFFSET_64);
+ } else {
+ phys = virt - FIXED_HIGHER_HALF_OFFSET_64;
+ }
} else {
panic("stivale2: Protected memory ranges are only supported for higher half kernels");
}
diff --git a/stage23/protos/stivale.h b/stage23/protos/stivale.h
index 5379dc3b..b4da17e0 100644
--- a/stage23/protos/stivale.h
+++ b/stage23/protos/stivale.h
@@ -10,7 +10,8 @@ void stivale_load(char *config, char *cmdline);
bool stivale_load_by_anchor(void **_anchor, const char *magic,
uint8_t *file, uint64_t filesize);
-pagemap_t stivale_build_pagemap(bool level5pg, bool unmap_null, struct elf_range *ranges, size_t ranges_count);
+pagemap_t stivale_build_pagemap(bool level5pg, bool unmap_null, struct elf_range *ranges, size_t ranges_count,
+ bool want_fully_virtual, uint64_t physical_base);
__attribute__((noreturn)) void stivale_spinup(
int bits, bool level5pg, pagemap_t *pagemap,
uint64_t entry_point, uint64_t stivale_struct, uint64_t stack,
diff --git a/stage23/protos/stivale2.c b/stage23/protos/stivale2.c
index 90675f56..d91aa686 100644
--- a/stage23/protos/stivale2.c
+++ b/stage23/protos/stivale2.c
@@ -32,22 +32,36 @@
struct stivale2_struct stivale2_struct = {0};
-inline static size_t get_phys_addr(uint64_t addr) {
- if (addr & ((uint64_t)1 << 63))
- return addr - FIXED_HIGHER_HALF_OFFSET_64;
- return addr;
-}
+#define get_phys_addr(addr) ({ \
+ uintptr_t r1; \
+ if ((addr) & ((uint64_t)1 << 63)) { \
+ if (want_fully_virtual) { \
+ r1 = physical_base + ((addr) - virtual_base); \
+ } else { \
+ r1 = (addr) - FIXED_HIGHER_HALF_OFFSET_64; \
+ } \
+ } else { \
+ r1 = addr; \
+ } \
+ r1; \
+})
-static void *get_tag(struct stivale2_header *s, uint64_t id) {
- struct stivale2_tag *tag = (void*)get_phys_addr(s->tags);
- for (;;) {
- if (tag == NULL)
- return NULL;
- if (tag->identifier == id)
- return tag;
- tag = (void*)get_phys_addr(tag->next);
- }
-}
+#define get_tag(s, id) ({ \
+ void *r; \
+ struct stivale2_tag *tag = (void *)get_phys_addr((s)->tags); \
+ for (;;) { \
+ if (tag == NULL) { \
+ r = NULL; \
+ break; \
+ } \
+ if (tag->identifier == (id)) { \
+ r = tag; \
+ break; \
+ } \
+ tag = (void *)get_phys_addr(tag->next); \
+ } \
+ r; \
+})
#define append_tag(S, TAG) ({ \
(TAG)->next = (S)->tags; \
@@ -110,6 +124,9 @@ void stivale2_load(char *config, char *cmdline, bool pxe, void *efi_system_table
}
bool want_pmrs = false;
+ bool want_fully_virtual = false;
+
+ uint64_t physical_base, virtual_base;
int ret = 0;
switch (bits) {
@@ -141,10 +158,15 @@ void stivale2_load(char *config, char *cmdline, bool pxe, void *efi_system_table
want_pmrs = true;
}
+ if (want_pmrs && (stivale2_hdr.flags & (1 << 3))) {
+ want_fully_virtual = true;
+ }
+
if (elf64_load(kernel, &entry_point, NULL, &slide,
STIVALE2_MMAP_KERNEL_AND_MODULES, kaslr, false,
want_pmrs ? &ranges : NULL,
- want_pmrs ? &ranges_count : NULL))
+ want_pmrs ? &ranges_count : NULL,
+ want_fully_virtual, &physical_base, &virtual_base))
panic("stivale2: ELF64 load failure");
ret = elf64_load_section(kernel, &stivale2_hdr, ".stivale2hdr",
@@ -579,6 +601,23 @@ have_tm_tag:;
}
}
+ //////////////////////////////////////////////
+ // Create PMRs struct tag
+ //////////////////////////////////////////////
+ {
+ if (want_fully_virtual) {
+ struct stivale2_struct_tag_kernel_base_address *tag =
+ ext_mem_alloc(sizeof(struct stivale2_struct_tag_kernel_base_address));
+
+ tag->tag.identifier = STIVALE2_STRUCT_TAG_KERNEL_BASE_ADDRESS_ID;
+
+ tag->physical_base_address = physical_base;
+ tag->virtual_base_address = virtual_base;
+
+ append_tag(&stivale2_struct, (struct stivale2_tag *)tag);
+ }
+ }
+
//////////////////////////////////////////////
// Create EFI system table struct tag
//////////////////////////////////////////////
@@ -599,7 +638,8 @@ have_tm_tag:;
if (bits == 64)
pagemap = stivale_build_pagemap(want_5lv, unmap_null,
want_pmrs ? ranges : NULL,
- want_pmrs ? ranges_count : 0);
+ want_pmrs ? ranges_count : 0,
+ want_fully_virtual, physical_base);
#if uefi == 1
efi_exit_boot_services();
diff --git a/test/Makefile b/test/Makefile
index 808862cc..45cb828f 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -1,5 +1,5 @@
CC = cc
-CFLAGS = -O2
+CFLAGS = -O2 -g
LDFLAGS =
LD = ld
QEMU = qemu-system-x86_64
@@ -9,10 +9,7 @@ INTERNALLDFLAGS := \
-Tlinker.ld \
-nostdlib \
-zmax-page-size=0x1000 \
- -static \
- -pie \
- --no-dynamic-linker \
- -ztext
+ -static
INTERNALCFLAGS := \
-I../stivale \
@@ -20,14 +17,15 @@ INTERNALCFLAGS := \
-std=gnu11 \
-ffreestanding \
-fno-stack-protector \
- -fno-pic -fpie \
+ -fno-pic -fno-pie \
-mabi=sysv \
-mno-80387 \
-mno-mmx \
-mno-3dnow \
-mno-sse \
-mno-sse2 \
- -mno-red-zone
+ -mno-red-zone \
+ -mcmodel=kernel
all: test.elf
diff --git a/test/linker.ld b/test/linker.ld
index 8c2ea098..18222830 100644
--- a/test/linker.ld
+++ b/test/linker.ld
@@ -6,12 +6,11 @@ PHDRS
text PT_LOAD FLAGS((1 << 0) | (1 << 2)) ; /* Execute + Read */
rodata PT_LOAD FLAGS((1 << 2)) ; /* Read only */
data PT_LOAD FLAGS((1 << 1) | (1 << 2)) ; /* Write + Read */
- dynamic PT_DYNAMIC FLAGS((1 << 1) | (1 << 2)) ; /* Dynamic segment needed for PIE */
}
SECTIONS
{
- . = 0xffffffff80200000;
+ . = 0xffffffff80000000;
.text : {
*(.text*)
@@ -37,10 +36,6 @@ SECTIONS
*(.data*)
} :data
- .dynamic : {
- *(.dynamic)
- } :data :dynamic
-
.bss : {
*(COMMON)
*(.bss*)
diff --git a/test/stivale2.c b/test/stivale2.c
index a69577a2..8a3d19ae 100644
--- a/test/stivale2.c
+++ b/test/stivale2.c
@@ -40,7 +40,7 @@ __attribute__((section(".stivale2hdr"), used))
struct stivale2_header header2 = {
.entry_point = (uint64_t)stivale2_main,
.stack = (uintptr_t)stacks[0] + sizeof(stack),
- .flags = (1 << 1) | (1 << 2),
+ .flags = (1 << 1) | (1 << 2) | (1 << 3),
.tags = (uint64_t)&any_video_request
};
@@ -204,6 +204,13 @@ void stivale2_main(struct stivale2_struct *info) {
}
break;
}
+ case STIVALE2_STRUCT_TAG_KERNEL_BASE_ADDRESS_ID: {
+ struct stivale2_struct_tag_kernel_base_address *t = (void *)tag;
+ e9_puts("Kernel base address:");
+ e9_printf("\tPhysical base address: %x", t->physical_base_address);
+ e9_printf("\tVirtual base address: %x", t->virtual_base_address);
+ break;
+ }
case STIVALE2_STRUCT_TAG_SMP_ID: {
struct stivale2_struct_tag_smp *s = (struct stivale2_struct_tag_smp *)tag;
e9_puts("SMP tag:");
