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#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <libmcpu.h>
#include "mcpu-asm.h"
#define TEST_NR_brk 10
#define CHECK(cond,msg) \
do { \
if( !(cond) ) \
{ \
fprintf( stderr, "FAIL: %s\n", (msg) ); \
return( 1 ); \
} \
} while( 0 )
static __mpu_uint64_t
reg64( __mpu_uint32_t address )
{
return( __cpu_data_get_u64( __cpu_reg_ptr( 64, address ) ) );
}
static void
put32( __mpu_uint32_t address, __mpu_uint32_t value )
{
__cpu_data_put_u32( __cpu_reg_ptr( 32, address ), value );
}
static void
put64( __mpu_uint32_t address, __mpu_uint64_t value )
{
__cpu_data_put_u64( __cpu_reg_ptr( 64, address ), value );
}
static int
run_syscall( __mpu_uint32_t nargs, __mpu_uint32_t sysno,
__mpu_uint64_t arg0, __mpu_uint64_t *ret )
{
__mpu_uint64_t keep1 = __mpu_UINT64_C( 0x1111111111111111 );
__mpu_uint64_t keep2 = __mpu_UINT64_C( 0x2222222222222222 );
__mpu_uint64_t keep3 = __mpu_UINT64_C( 0x3333333333333333 );
__mpu_uint64_t keep4 = __mpu_UINT64_C( 0x4444444444444444 );
__mpu_uint64_t keep5 = __mpu_UINT64_C( 0x5555555555555555 );
int rc;
put32( CPU_SYSCALL_NARGS_ADDR, nargs );
put32( CPU_SYSCALL_SYSNO_ADDR, sysno );
put64( CPU_SYSCALL_ARG0_ADDR, arg0 );
put64( CPU_SYSCALL_ARG1_ADDR, keep1 );
put64( CPU_SYSCALL_ARG2_ADDR, keep2 );
put64( CPU_SYSCALL_ARG3_ADDR, keep3 );
put64( CPU_SYSCALL_ARG4_ADDR, keep4 );
put64( CPU_SYSCALL_ARG5_ADDR, keep5 );
__cpu_pc = 0;
rc = __cpu_run();
if( rc != CPU_EXEC_SUCCESS ) return( rc );
*ret = reg64( CPU_SYSCALL_RET_ADDR );
if( reg64( CPU_SYSCALL_ARG0_ADDR ) != arg0 ||
reg64( CPU_SYSCALL_ARG1_ADDR ) != keep1 ||
reg64( CPU_SYSCALL_ARG2_ADDR ) != keep2 ||
reg64( CPU_SYSCALL_ARG3_ADDR ) != keep3 ||
reg64( CPU_SYSCALL_ARG4_ADDR ) != keep4 ||
reg64( CPU_SYSCALL_ARG5_ADDR ) != keep5 )
return( -1000 );
return( 0 );
}
static void
regop( cpu_operand *o, unsigned int bits, __mpu_uint32_t address )
{
memset( o, 0, sizeof( *o ) );
o->type = CPU_OPERAND_REGISTER;
o->value.reg.bits = bits;
o->value.reg.address = address;
}
int
main( void )
{
static const char source[] =
".text\n"
"SYSCALL\n"
"HALT\n";
cpu_asm_image image;
cpu_instruction store;
char err[256];
__mpu_uint64_t ptr, ret;
__mpu_int64_t sret;
size_t i;
memset( &image, 0, sizeof( image ) );
__cpu_init();
CHECK( CPU_SYSCALL_NARGS_ADDR == CPU_SYSCALL_RET_ADDR,
"NARGS overlaps low-address half of RET storage" );
CHECK( CPU_SYSCALL_SYSNO_ADDR == CPU_SYSCALL_RET_ADDR + 4,
"SYSNO overlaps second half of RET storage" );
CHECK( CPU_SYSCALL_ARG0_ADDR + 8 == CPU_SYSCALL_RET_ADDR,
"ARG0 is immediately below RET" );
CHECK( cpu_assemble_text( source, &image, err, sizeof( err ) ) == 0, err );
CHECK( image.code_size == 4, "SYSCALL/HALT code size" );
CHECK( image.code[0] == 0x00 && image.code[1] == 0x04,
"SYSCALL opcode encoding" );
CHECK( __cpu_program_set( image.code, image.code_size ) == 0,
"program load" );
CHECK( __cpu_heap_alloc( 64, 8192 ) == 0, "heap allocation" );
CHECK( __cpu_ptr_make( &ptr, CPU_PTR_SEG_HEAP, CPU_HEAP_BEGIN ) == 0,
"make initial HEAP pointer" );
put64( 0x00000, ptr );
put64( 0x00008, __mpu_UINT64_C( 0xa5a5a5a5a5a5a5a5 ) );
memset( &store, 0, sizeof( store ) );
store.opcode = CPU_OP_STOREP;
regop( &store.operand[0], 64, 0x00000 );
regop( &store.operand[1], 64, 0x00008 );
CHECK( __cpu_exec( &store ) == CPU_EXEC_MEMORY_FAULT,
"initial break protects HEAP above _end" );
CHECK( run_syscall( 1, TEST_NR_brk, CPU_NULL_PTR, &ret ) == 0,
"SYS_brk query" );
CHECK( __cpu_ptr_segment( ret ) == CPU_PTR_SEG_HEAP &&
__cpu_ptr_offset( ret ) == CPU_HEAP_BEGIN,
"initial SYS_brk is HEAP:16" );
CHECK( __cpu_ptr_make( &ptr, CPU_PTR_SEG_HEAP, CPU_HEAP_BEGIN + 8 ) == 0,
"make grown break" );
CHECK( run_syscall( 1, TEST_NR_brk, ptr, &ret ) == 0,
"SYS_brk grow inside initial heap size" );
CHECK( ret == ptr, "SYS_brk grow return" );
CHECK( __cpu_exec( &store ) == CPU_EXEC_SUCCESS,
"HEAP becomes writable below new break" );
memset( __cpu_heap_ptr() + CPU_HEAP_BEGIN, 0x5a, 8 );
CHECK( __cpu_ptr_make( &ptr, CPU_PTR_SEG_HEAP, CPU_HEAP_BEGIN ) == 0,
"make shrink break" );
CHECK( run_syscall( 1, TEST_NR_brk, ptr, &ret ) == 0,
"SYS_brk shrink to _end" );
CHECK( ret == ptr, "SYS_brk shrink return" );
for( i = 0; i < 8; ++i )
CHECK( __cpu_heap_ptr()[CPU_HEAP_BEGIN + i] == 0,
"shrink zeroes released HEAP" );
CHECK( __cpu_heap_size() == 64,
"shrink does not reduce logical backing size" );
CHECK( __cpu_exec( &store ) == CPU_EXEC_MEMORY_FAULT,
"shrunk HEAP is inaccessible above _end" );
CHECK( __cpu_ptr_make( &ptr, CPU_PTR_SEG_HEAP, CPU_HEAP_BEGIN + 8 ) == 0,
"make regrown break" );
CHECK( run_syscall( 1, TEST_NR_brk, ptr, &ret ) == 0,
"SYS_brk regrow inside retained backing" );
CHECK( ret == ptr, "SYS_brk regrow return" );
for( i = 0; i < 8; ++i )
CHECK( __cpu_heap_ptr()[CPU_HEAP_BEGIN + i] == 0,
"regrown released HEAP remains zero" );
CHECK( __cpu_ptr_make( &ptr, CPU_PTR_SEG_HEAP, 1000 ) == 0,
"make break inside host capacity" );
CHECK( run_syscall( 1, TEST_NR_brk, ptr, &ret ) == 0,
"SYS_brk extends logical heap" );
CHECK( ret == ptr && __cpu_heap_size() == 1000,
"logical heap extension" );
__cpu_heap_ptr()[900] = 0x6b;
CHECK( __cpu_ptr_make( &ptr, CPU_PTR_SEG_HEAP, 5000 ) == 0,
"make break requiring backing growth" );
CHECK( run_syscall( 1, TEST_NR_brk, ptr, &ret ) == 0,
"SYS_brk grows host backing" );
CHECK( ret == ptr && __cpu_heap_size() == 5000,
"host-backed heap extension" );
CHECK( __cpu_heap_ptr()[900] == 0x6b,
"heap relocation preserves old contents" );
CHECK( __cpu_heap_ptr()[4999] == 0,
"newly allocated heap memory is zero" );
CHECK( __cpu_ptr_make( &ptr, CPU_PTR_SEG_HEAP, 8193 ) == 0,
"make break above immutable limit" );
CHECK( run_syscall( 1, TEST_NR_brk, ptr, &ret ) == 0,
"SYS_brk above limit returns normally" );
CHECK( __cpu_ptr_segment( ret ) == CPU_PTR_SEG_HEAP &&
__cpu_ptr_offset( ret ) == 5000 && __cpu_heap_size() == 5000,
"heap limit rejection preserves current break" );
CHECK( __cpu_ptr_make( &ptr, CPU_PTR_SEG_DATA, 32 ) == 0,
"make non-HEAP pointer" );
CHECK( run_syscall( 1, TEST_NR_brk, ptr, &ret ) == 0,
"SYS_brk rejects non-HEAP pointer" );
CHECK( __cpu_ptr_offset( ret ) == 5000,
"invalid SYS_brk returns current break" );
CHECK( __cpu_ptr_make( &ptr, CPU_PTR_SEG_HEAP, 6000 ) == 0,
"make break for bad NARGS" );
CHECK( run_syscall( 2, TEST_NR_brk, ptr, &ret ) == 0,
"SYS_brk bad NARGS" );
CHECK( __cpu_ptr_offset( ret ) == 5000,
"bad SYS_brk NARGS returns current break" );
CHECK( run_syscall( 0, 9, 0, &ret ) == 0,
"unimplemented syscall execution" );
memcpy( &sret, &ret, sizeof( sret ) );
CHECK( sret == -(__mpu_int64_t)ENOSYS,
"unimplemented syscall returns -ENOSYS" );
cpu_asm_image_free( &image );
__cpu_free_context();
puts( "libmcpu SYSCALL/SYS_brk regression: PASS" );
return( 0 );
} /* End of main() */
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