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Added detailed mapping of bss.

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.data and .text now needs to be 4K apart.
removed an early copy of test0 called test1
This commit is contained in:
Bahadir Balban
2008-11-23 21:27:11 +02:00
parent 311d6917c4
commit d0e878b32c
12 changed files with 119 additions and 386 deletions
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62
tasks/mm0/src/lib/elf/elf.c
View File

@@ -5,6 +5,7 @@
*/
#include <memory.h>
#include <vm_area.h>
#include <l4/api/errno.h>
#include <lib/elf/elf.h>
#include <lib/elf/elfprg.h>
#include <lib/elf/elfsym.h>
@@ -39,6 +40,7 @@ int elf_test_expand_segment(struct elf_section_header *section,
(section->sh_flags & sec_flmask) == sec_flags) {
/* Set new section */
if (!*start) {
BUG_ON(*offset || *end);
*offset = section->sh_offset;
*start = section->sh_addr;
*end = section->sh_addr + section->sh_size;
@@ -49,13 +51,11 @@ int elf_test_expand_segment(struct elf_section_header *section,
return 0;
}
/*
* Sift through sections and copy their marks to tcb and efd
* if they are recognised and loadable sections.
*
* NOTE: There may be multiple sections of same kind, in
* consecutive address regions. Then we need to increase
* that region's marks.
* if they are recognised and loadable sections. Test the
* assigned segment marks and return an error if they're invalid.
*/
int elf_mark_segments(struct elf_section_header *sect_header, int nsections,
struct tcb *task, struct exec_file_desc *efd)
@@ -64,24 +64,45 @@ int elf_mark_segments(struct elf_section_header *sect_header, int nsections,
struct elf_section_header *section = &sect_header[i];
/* Text + read-only data segments */
elf_test_expand_segment(section, SHT_PROGBITS, SHF_ALLOC,
SHF_ALLOC | SHF_WRITE, &task->text_start,
&task->text_end, &efd->text_offset);
elf_test_expand_segment(section, SHT_PROGBITS,
SHF_ALLOC, SHF_ALLOC | SHF_WRITE,
&task->text_start, &task->text_end,
&efd->text_offset);
/* Data segment */
elf_test_expand_segment(section, SHT_PROGBITS, SHF_ALLOC | SHF_WRITE,
SHF_ALLOC | SHF_WRITE, &task->data_start,
&task->data_end, &efd->data_offset);
elf_test_expand_segment(section, SHT_PROGBITS, SHF_ALLOC |
SHF_WRITE, SHF_ALLOC | SHF_WRITE,
&task->data_start, &task->data_end,
&efd->data_offset);
/* Bss segment */
elf_test_expand_segment(section, SHT_NOBITS, SHF_ALLOC | SHF_WRITE,
SHF_ALLOC | SHF_WRITE, &task->bss_start,
&task->bss_end, &efd->bss_offset);
elf_test_expand_segment(section, SHT_NOBITS, SHF_ALLOC |
SHF_WRITE, SHF_ALLOC | SHF_WRITE,
&task->bss_start, &task->bss_end,
&efd->bss_offset);
}
if (!task->text_start || !task->data_start || !task->bss_start) {
printf("%s: NOTE: Could not find one of text, data or "
"bss segments in elf file.\n", __FUNCTION__);
/* Test anomalies with the mappings */
/* No text */
if (!task->text_start) {
printf("%s: Error: Could not find a text "
"segment in ELF file.\n", __FUNCTION__);
return -ENOEXEC;
}
/* Warn if no data or bss but it's not an error */
if (!task->data_start || !task->bss_start) {
printf("%s: NOTE: Could not find a data and/or "
"bss segment in ELF file.\n", __FUNCTION__);
}
/* Data and text are less than page apart */
if ((task->data_start - task->text_start) < PAGE_SIZE) {
printf("%s: Error: Distance between data and text"
" sections are less than page size (4K)\n",
__FUNCTION__);
return -ENOEXEC;
}
return 0;
@@ -105,7 +126,7 @@ int elf_parse_executable(struct tcb *task, struct vm_file *file,
struct elf_section_header *sect_header;
unsigned long sect_offset, sect_size;
unsigned long prg_offset, prg_size;
int err;
int err = 0;
/* Test that it is a valid elf file */
if ((err = elf_probe(elf_headerp)) < 0)
@@ -138,7 +159,8 @@ int elf_parse_executable(struct tcb *task, struct vm_file *file,
sect_header = (struct elf_section_header *)
pager_map_file_range(file, sect_offset, sect_size);
elf_mark_segments(sect_header, elf_header.e_shnum, task, efd);
/* Copy segment marks from ELF file to task + efd. Return errors */
err = elf_mark_segments(sect_header, elf_header.e_shnum, task, efd);
/* Unmap program header table */
pager_unmap_pages(prg_header_start, __pfn(page_align_up(prg_size)));
@@ -146,6 +168,6 @@ int elf_parse_executable(struct tcb *task, struct vm_file *file,
/* Unmap section header table */
pager_unmap_pages(sect_header, __pfn(page_align_up(sect_size)));
return 0;
return err;
}

84
tasks/mm0/src/task.c
View File

@@ -16,6 +16,7 @@
#include <l4lib/arch/utcb.h>
#include <l4lib/ipcdefs.h>
#include <l4lib/exregs.h>
#include <l4/lib/math.h>
#include <lib/addr.h>
#include <lib/malloc.h>
#include <init.h>
@@ -342,12 +343,79 @@ struct tcb *task_create(struct tcb *parent, struct task_ids *ids,
return task;
}
/*
* If bss comes consecutively after the data section, prefault the
* last page of the data section and zero out the bit that contains
* the beginning of bss. If bss spans into more pages, then map those
* pages as anonymous pages which are mapped by the devzero file.
*/
int task_map_bss(struct vm_file *f, struct exec_file_desc *efd, struct tcb *task)
{
unsigned long bss_mmap_start;
void *mapped;
/*
* Test if bss starts right from the end of data,
* and not on a new page boundary.
*/
if ((task->data_end == task->bss_start) &&
!is_page_aligned(task->bss_start)) {
unsigned long bss_size = task->bss_end - task->bss_start;
struct page *last_data_page;
void *pagebuf, *bss;
/* Prefault the last data page */
BUG_ON(prefault_page(task, task->data_end,
VM_READ | VM_WRITE) < 0);
/* Get the page */
last_data_page = task_virt_to_page(task, task->data_end);
/* Map the page */
pagebuf = l4_map_helper((void *)page_to_phys(last_data_page), 1);
/* Find the bss offset */
bss = (void *)((unsigned long)pagebuf |
(PAGE_MASK & task->bss_start));
/*
* Zero out the part that is bss. This is minimum of either
* end of bss or until the end of page, whichever is met first.
*/
memset((void *)bss, 0, min(TILL_PAGE_ENDS(task->data_end),
(int)bss_size));
/* Unmap the page */
l4_unmap_helper(pagebuf, 1);
/* Push bss mmap start to next page */
bss_mmap_start = page_align_up(task->bss_start);
} else /* Otherwise bss mmap start is same as bss_start */
bss_mmap_start = task->bss_start;
/*
* Now if there are more pages covering bss,
* map those as anonymous zero pages
*/
if (task->bss_end > bss_mmap_start) {
if (IS_ERR(mapped = do_mmap(0, 0, task, task->bss_start,
VM_READ | VM_WRITE |
VMA_PRIVATE | VMA_ANONYMOUS,
__pfn(page_align_up(task->bss_end) -
page_align(task->bss_start))))) {
printf("do_mmap: Mapping environment failed with %d.\n",
(int)mapped);
return (int)mapped;
}
}
return 0;
}
int task_mmap_segments(struct tcb *task, struct vm_file *file, struct exec_file_desc *efd)
{
void *mapped;
struct vm_file *shm;
/* Set up heap as one page after bss */
int err;
/* mmap task's text to task's address space. */
if (IS_ERR(mapped = do_mmap(file, efd->text_offset, task, task->text_start,
@@ -368,14 +436,12 @@ int task_mmap_segments(struct tcb *task, struct vm_file *file, struct exec_file_
}
/* mmap task's bss as anonymous memory. */
if (IS_ERR(mapped = do_mmap(0, 0, task, task->bss_start,
VM_READ | VM_WRITE |
VMA_PRIVATE | VMA_ANONYMOUS,
__pfn(task->bss_end - task->bss_start)))) {
printf("do_mmap: Mapping environment failed with %d.\n",
(int)mapped);
return (int)mapped;
if ((err = task_map_bss(file, efd, task)) < 0) {
printf("%s: Mapping bss has failed.\n",
__FUNCTION__);
return err;
}
/* mmap task's environment as anonymous memory. */
if (IS_ERR(mapped = do_mmap(0, 0, task, task->env_start,
VM_READ | VM_WRITE |

3
tasks/test0/include/linker.lds
View File

@@ -30,9 +30,10 @@ SECTIONS
/* rodata is needed else your strings will link at physical! */
.rodata : AT (ADDR(.rodata) - offset) { *(.rodata) }
.rodata1 : AT (ADDR(.rodata1) - offset) { *(.rodata1) }
. = ALIGN(4K);
.data : AT (ADDR(.data) - offset)
{
. = ALIGN(4K);
_start_test1 = .;
*(.test1)
_end_test1 = .;

78
tasks/test1/SConstruct
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@@ -1,78 +0,0 @@
#
# User space application build script
#
# Copyright (C) 2007 Bahadir Balban
#
import os
import sys
import shutil
from os.path import join
from glob import glob
task_name = "test1"
# The root directory of the repository where this file resides:
project_root = "../.."
tools_root = join(project_root, "tools")
prev_image = join(project_root, "tasks/test0/test0.axf")
libs_path = join(project_root, "libs")
ld_script = "include/linker.lds"
physical_base_ld_script = "include/physical_base.lds"
# Libc situation:
# Libposix has uClibc (and therefore posix) headers.
# NICTA libc implements printf for us for now.
# Libposix implements posix calls for us, e.g. mmap.
# In conclusion nicta libc and libposix complement each other
# they should not clash. In future libposix will be part of uclibc
# and uclibc will be used.
# libc paths:
libc_variant = "userspace"
libc_libpath = join(libs_path, "c/build/%s" % libc_variant)
libc_incpath = join(libc_libpath, "include")
libc_crt0 = join(libs_path, "c/build/crt/sys-userspace/arch-arm/crt0.o")
libc_name = "c-%s" % libc_variant
# libposix paths:
libposix_libpath = "../libposix"
libposix_incpath = "../libposix/include/posix"
# libl4 paths:
libl4_path = "../libl4"
libl4_incpath = join(libl4_path, "include")
# kernel paths:
kernel_incpath = join(project_root, "include")
# If crt0 is in its library path, it becomes hard to link with it.
# For instance the linker script must use an absolute path for it.
def copy_crt0(source, target, env):
os.system("cp " + str(source[0]) + " " + str(target[0]))
def get_physical_base(source, target, env):
os.system(join(tools_root, "pyelf/readelf.py --first-free-page " + \
prev_image + " >> " + physical_base_ld_script))
# The kernel build environment:
env = Environment(CC = 'arm-none-linux-gnueabi-gcc',
# We don't use -nostdinc because sometimes we need standard headers,
# such as stdarg.h e.g. for variable args, as in printk().
CCFLAGS = ['-g', '-nostdlib', '-ffreestanding', '-std=gnu99', '-Wall', '-Werror'],
LINKFLAGS = ['-nostdlib', '-T' + ld_script, "-L" + libc_libpath, "-L" + libl4_path, \
'-L' + libposix_libpath],
ASFLAGS = ['-D__ASSEMBLY__'],
PROGSUFFIX = '.axf', # The suffix to use for final executable
ENV = {'PATH' : os.environ['PATH']}, # Inherit shell path
LIBS = [libc_name, 'gcc', libc_name, 'libl4', 'libposix'],
CPPFLAGS = "-D__USERSPACE__",
CPPPATH = ['#include', libl4_incpath, libposix_incpath, kernel_incpath])
src = [glob("src/*.c"), glob("*.c"), glob("src/arch/arm/*.c")]
objs = env.Object(src)
physical_base = env.Command(physical_base_ld_script, prev_image, get_physical_base)
crt0_copied = env.Command("crt0.o", libc_crt0, copy_crt0)
task = env.Program(task_name, objs + [crt0_copied])
env.Alias(task_name, task)
env.Depends(task, physical_base)

1
tasks/test1/include/.gitignore vendored
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@@ -1 +0,0 @@
physical_base.lds

36
tasks/test1/include/linker.lds
View File

@@ -1,36 +0,0 @@
/*
* Simple linker script for userspace or svc tasks.
*
* Copyright (C) 2007 Bahadir Balban
*/
/*
* The only catch with this linker script is that everything
* is linked starting at virtual_base, and loaded starting
* at physical_base. virtual_base is the predefined region
* of virtual memory for userland applications. physical_base
* is determined at build-time, it is one of the subsequent pages
* that come after the kernel image's load area.
*/
/* USER_AREA_START, see memlayout.h */
virtual_base = 0x10000000;
__stack = 0x20000000;
INCLUDE "include/physical_base.lds"
/* physical_base = 0x228000; */
offset = virtual_base - physical_base;
ENTRY(_start)
SECTIONS
{
. = virtual_base;
_start_text = .;
.text : AT (ADDR(.text) - offset) { crt0.o(.text) *(.text) }
/* rodata is needed else your strings will link at physical! */
.rodata : AT (ADDR(.rodata) - offset) { *(.rodata) }
.rodata1 : AT (ADDR(.rodata1) - offset) { *(.rodata1) }
.data : AT (ADDR(.data) - offset) { *(.data) }
.bss : AT (ADDR(.bss) - offset) { *(.bss) }
_end = .;
}

7
tasks/test1/include/tests.h
View File

@@ -1,7 +0,0 @@
#ifndef __TEST0_TESTS_H__
#define __TEST0_TESTS_H__
int shmtest(void);
int mmaptest(void);
#endif /* __TEST0_TESTS_H__ */

36
tasks/test1/main.c
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@@ -1,36 +0,0 @@
/*
* Some tests for posix syscalls.
*
* Copyright (C) 2007 Bahadir Balban
*/
#include <stdio.h>
#include <string.h>
#include <l4lib/arch/message.h>
#include <l4lib/arch/syslib.h>
#include <l4lib/kip.h>
#include <l4lib/utcb.h>
#include <l4/api/ipc.h>
#include <tests.h>
#define __TASKNAME__ "test0"
void wait_pager(l4id_t partner)
{
u32 tag = L4_IPC_TAG_WAIT;
printf("%s: Syncing with pager.\n", __TASKNAME__);
l4_send(partner, tag);
printf("Pager synced with us.\n");
}
void main(void)
{
/* Sync with pager */
wait_pager(0);
/* Check mmap/munmap */
mmaptest();
/* Check shmget/shmat/shmdt */
shmtest();
}

60
tasks/test1/src/mmaptest.c
View File

@@ -1,60 +0,0 @@
/*
* Test mmap/munmap posix calls.
*
* Copyright (C) 2007 - 2008 Bahadir Balban
*/
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/stat.h>
#include <unistd.h>
#include <tests.h>
#define PAGE_SIZE 0x1000
int mmaptest(void)
{
int fd;
void *base;
int x = 0x1000;
if ((fd = open("./newfile.txt", O_CREAT | O_TRUNC | O_RDWR, S_IRWXU)) < 0)
perror("open:");
else
printf("open: Success.\n");
/* Extend the file */
if ((int)lseek(fd, PAGE_SIZE*16, SEEK_SET) < 0)
perror("lseek");
else
printf("lseek: Success.\n");
if (write(fd, &x, sizeof(x)) < 0)
perror("write");
else
printf("write: Success.\n");
if ((int)(base = mmap(0, PAGE_SIZE*16, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0)) < 0)
perror("mmap");
else
printf("mmap: Success: %p\n", base);
*(unsigned int *)(base + PAGE_SIZE*2) = 0x1000;
if (msync(base + PAGE_SIZE*2, PAGE_SIZE, MS_SYNC) < 0)
perror("msync");
else
printf("msync: Success: %p\n", base);
if (munmap(base + PAGE_SIZE*2, PAGE_SIZE) < 0)
perror("munmap");
else
printf("munmap: Success: %p\n", base);
*(unsigned int *)(base + PAGE_SIZE*3) = 0x1000;
*(unsigned int *)(base + PAGE_SIZE*1) = 0x1000;
return 0;
}

60
tasks/test1/src/mmaptest.c.orig
View File

@@ -1,60 +0,0 @@
/*
* Test mmap/munmap posix calls.
*
* Copyright (C) 2007 - 2008 Bahadir Balban
*/
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/stat.h>
#include <unistd.h>
#include <tests.h>
#define PAGE_SIZE 0x1000
int mmaptest(void)
{
int fd;
void *base;
int x = 0x1000;
if ((fd = open("./newfile.txt", O_CREAT | O_TRUNC | O_RDWR, S_IRWXU)) < 0)
perror("open:");
else
printf("open: Success.\n");
/* Extend the file */
if ((int)lseek(fd, PAGE_SIZE*16, SEEK_SET) < 0)
perror("lseek");
else
printf("lseek: Success.\n");
if (write(fd, &x, sizeof(x)) < 0)
perror("write");
else
printf("write: Success.\n");
if ((int)(base = mmap(0, PAGE_SIZE*16, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0)) < 0)
perror("mmap");
else
printf("mmap: Success: %p\n", base);
*(unsigned int *)(base + PAGE_SIZE*2) = 0x1000;
if (msync(base + PAGE_SIZE*2, PAGE_SIZE, MS_SYNC) < 0)
perror("msync");
else
printf("msync: Success: %p\n", base);
if (munmap(base + PAGE_SIZE*2, PAGE_SIZE) < 0)
perror("munmap");
else
printf("munmap: Success: %p\n", base);
*(unsigned int *)(base + PAGE_SIZE*3) = 0x1000;
*(unsigned int *)(base + PAGE_SIZE*1) = 0x1000;
return 0;
}

51
tasks/test1/src/shmtest.c
View File

@@ -1,51 +0,0 @@
/*
* Test shmget/shmat/shmdt posix calls.
*
* Copyright (C) 2007 - 2008 Bahadir Balban
*/
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/types.h>
#include <fcntl.h>
#include <stdio.h>
#include <tests.h>
int shmtest(void)
{
//key_t keys[2] = { 5, 10000 };
key_t keys[2] = { 2, 3 };
void *bases[2] = { 0 , 0 };
int shmids[2];
printf("Initiating shmget()\n");
for (int i = 0; i < 2; i++) {
if ((shmids[i] = shmget(keys[i], 27, IPC_CREAT | 0666)) < 0) {
printf("Call failed.\n");
perror("SHMGET");
} else
printf("SHMID returned: %d\n", shmids[i]);
}
printf("Now shmat()\n");
for (int i = 0; i < 2; i++) {
if ((int)(bases[i] = shmat(shmids[i], NULL, 0)) == -1)
perror("SHMAT");
else
printf("SHM base address returned: %p\n", bases[i]);
}
printf("Now shmdt()\n");
for (int i = 0; i < 2; i++) {
if (shmdt(bases[i]) < 0)
perror("SHMDT");
else
printf("SHM detached OK.\n");
}
printf("Now shmat() again\n");
for (int i = 0; i < 2; i++) {
if ((int)(bases[i] = shmat(shmids[i], NULL, 0)) == -1)
perror("SHMAT");
else
printf("SHM base address returned: %p\n", bases[i]);
}
return 0;
}

27
tasks/test1/tools/generate_bootdesc.py
View File

@@ -1,27 +0,0 @@
#!/usr/bin/python
import os
import sys
compiler_prefix = "arm-linux-"
objdump = "objdump"
command = "-t"
image_name = "roottask.axf"
linkoutput_file_suffix = "-linkinfo.txt"
linkoutput_file = image_name + linkoutput_file_suffix
def generate_bootdesc():
command = compiler_prefix + objdump + " -t " + image_name + " > " + linkoutput_file
print command
os.system(command)
f = open(linkoutput_file, "r")
while True:
line = f.readline()
if len(line) is 0:
break
if "_start" in line or "_end" in line:
print line
f.close()
if __name__ == "__main__":
generate_bootdesc()