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uti: Replace data types represented as arrays with C structures

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Defining C structures for the following objects:
(1) Remote and local context
(2) Stack of system call arguments / return values

Change-Id: Iafbb6c795bd765e3c78c54a255d8a1e4d4536288
This commit is contained in:
Masamichi Takagi
2018-09-03 18:20:00 +09:00
parent 04d4145b3e
commit 781a69617b
12 changed files with 215 additions and 188 deletions
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28
executer/user/arch/x86_64/archdep.S
View File

@@ -1,15 +1,22 @@
/*
arg: rdi, rsi, rdx, rcx, r8, r9
ret: rax
Calling convention:
arg: rdi, rsi, rdx, rcx, r8, r9
ret: rax
rax syscall number
syscall: (rax:num) rdi rsi rdx r10 r8 r9 (rcx:ret addr)
fd, cmd, param
rdi: fd
rsi: cmd
rdx: param
rcx: save area
r8: new thread context
rdi: fd
rsi: cmd
rdx: param
rcx: save area
r8: new thread context
Syscam call convention:
syscall number: rax
arg: rdi, rsi, rdx, r10, r8, r9
return addr: rcx
rdi: fd
rsi: cmd
rdx: param
*/
.global switch_ctx
@@ -91,6 +98,7 @@ switch_ctx:
1:
mov $0xffffffffffffffff,%eax
retq
2:
pushq %rax
movq $158,%rax /* arch_prctl */

4
executer/user/archdep.h
View File

@@ -1,4 +1,6 @@
extern int switch_ctx(int fd, unsigned long cmd, void **param, void *lctx, void *rctx);
#include "../include/uprotocol.h"
extern int switch_ctx(int fd, unsigned long cmd, struct uti_save_fs_desc *desc, void *lctx, void *rctx);
extern unsigned long compare_and_swap(unsigned long *addr, unsigned long old, unsigned long new);
extern unsigned int compare_and_swap_int(unsigned int *addr, unsigned int old, unsigned int new);
extern int archdep_syscall(struct syscall_wait_desc *w, long *ret);

101
executer/user/mcexec.c
View File

@@ -2881,18 +2881,18 @@ static void kill_thread(unsigned long tid, int sig)
}
}
static long util_thread(struct thread_data_s *my_thread, unsigned long uctx_pa, int remote_tid, unsigned long pattr, unsigned long uti_clv, unsigned long _uti_desc)
static long util_thread(struct thread_data_s *my_thread, unsigned long rp_rctx, int remote_tid, unsigned long pattr, unsigned long uti_clv, unsigned long _uti_desc)
{
int i;
void *lctx;
void *rctx;
void *param[7];
struct uti_get_ctx_desc get_ctx_desc;
struct uti_save_fs_desc save_fs_desc;
int rc = 0;
void *uti_wp = (void*)-1;
struct thread_data_s *tp;
pthread_barrier_init(&uti_init_ready, NULL, 2);
if ((rc = create_worker_thread(&tp, &uti_init_ready))) {
printf("%s: Error: create_worker_thread failed (%d)\n", __FUNCTION__, rc);
rc = -EINVAL;
goto out;
}
pthread_barrier_wait(&uti_init_ready);
@@ -2900,18 +2900,12 @@ static long util_thread(struct thread_data_s *my_thread, unsigned long uctx_pa,
uti_desc = (struct uti_desc *)_uti_desc;
if (!uti_desc) {
fprintf(stderr, "%s: ERROR: uti_desc isn't set. Use mcexec.sh instead of mcexec\n", __FUNCTION__);
exit(1);
printf("%s: ERROR: uti_desc isn't set. Use mcexec.sh instead of mcexec\n", __FUNCTION__);
rc = -EINVAL;
goto out;
}
/* Initialize uti related variables for syscall_intercept */
uti_wp = mmap(NULL, PAGE_SIZE * 3, PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_ANONYMOUS, -1, 0);
if (uti_wp == (void *)-1) {
exit(1);
}
uti_desc->fd = fd;
rc = syscall(888);
@@ -2919,42 +2913,21 @@ static long util_thread(struct thread_data_s *my_thread, unsigned long uctx_pa,
fprintf(stderr, "%s: WARNING: syscall_intercept returned %x\n", __FUNCTION__, rc);
}
/* Get the context of the thread migrating to Linux */
#ifdef POSTK_DEBUG_ARCH_DEP_35
lctx = (char *)uti_wp + page_size;
rctx = (char *)lctx + page_size;
#else
lctx = (char *)uti_wp + PAGE_SIZE;
rctx = (char *)lctx + PAGE_SIZE;
#endif /* POSTK_DEBUG_ARCH_DEP_35 */
/* Get the remote context, record refill tid */
get_ctx_desc.rp_rctx = rp_rctx;
get_ctx_desc.rctx = uti_desc->rctx;
get_ctx_desc.lctx = uti_desc->lctx;
get_ctx_desc.uti_refill_tid = tp->tid;
param[0] = (void *)uctx_pa; /* Source address, kernel space */
param[1] = rctx; /* Destination address, user space */
param[2] = lctx;
param[4] = uti_desc->wp;
#ifdef POSTK_DEBUG_ARCH_DEP_35
param[5] = (void *)(page_size * 3);
#else /* POSTK_DEBUG_ARCH_DEP_35 */
param[5] = (void *)(PAGE_SIZE * 3);
#endif /* POSTK_DEBUG_ARCH_DEP_35 */
param[6] = (void *)tp->tid;
printf("%s: param[6]=%ld,tid=%ld\n", __FUNCTION__, (long)param[6], (long)((void *)tp->tid));
__dprintf("%s: before MCEXEC_UP_UTIL_THREAD1\n", __FUNCTION__);
/* 1. Copy context from kernel space to user space
2. Write uti_wp addr, its size for McKernel to uctx_pa
Note that this overwrites context */
if ((rc = ioctl(fd, MCEXEC_UP_UTIL_THREAD1, param)) == -1) {
fprintf(stderr, "util_thread1: %d errno=%d\n", rc, errno);
if ((rc = ioctl(fd, MCEXEC_UP_UTI_GET_CTX, &get_ctx_desc))) {
fprintf(stderr, "%s: Error: MCEXEC_UP_UTI_GET_CTX failed (%d)\n", __FUNCTION__, errno);
rc = -errno;
goto out;
}
/* Record the info of the thread migrating to Linux */
uti_desc->wp = uti_wp;
/* Initialize uti thread info */
uti_desc->mck_tid = remote_tid;
uti_desc->key = (unsigned long)param[3]; /* key to find thread, i.e. struct task_struct * */
uti_desc->key = get_ctx_desc.key;
uti_desc->pid = getpid();
uti_desc->tid = gettid();
uti_desc->uti_clv = uti_clv;
@@ -2965,12 +2938,6 @@ static long util_thread(struct thread_data_s *my_thread, unsigned long uctx_pa,
rc = -ENOMEM;
goto out;
}
for (i = 1; i <= 10; i++) {
uti_desc->syscall_param = (struct syscall_struct *)uti_desc->wp + i;
*(void **)uti_desc->syscall_param = uti_desc->syscall_param_top;
uti_desc->syscall_param_top = uti_desc->syscall_param;
}
memset(uti_desc->wp, '\0', sizeof(long));
if (pattr) {
struct uti_attr_desc desc;
@@ -2979,30 +2946,22 @@ static long util_thread(struct thread_data_s *my_thread, unsigned long uctx_pa,
ioctl(fd, MCEXEC_UP_UTI_ATTR, &desc);
}
/* McKernel would create the thread detached, so detach myself */
if ((rc = pthread_detach(my_thread->thread_id)) < 0) {
fprintf(stderr, "%s: ERROR pthread_detach returned %d\n", __FUNCTION__, rc);
goto out;
}
my_thread->detached = 1;
/* Start intercepting syscalls. Note that it dereferences pointers in uti_desc. */
uti_desc->start_syscall_intercept = 1;
if ((rc = switch_ctx(fd, MCEXEC_UP_UTIL_THREAD2, param, lctx, rctx))
/* Save remote and local FS and then contex-switch */
save_fs_desc.rctx = uti_desc->rctx;
save_fs_desc.lctx = uti_desc->lctx;
if ((rc = switch_ctx(fd, MCEXEC_UP_UTI_SAVE_FS, &save_fs_desc, uti_desc->lctx, uti_desc->rctx))
< 0) {
fprintf(stderr, "%s: ERROR switch_ctx returned %d\n", __FUNCTION__, rc);
fprintf(stderr, "%s: ERROR switch_ctx failed (%d)\n", __FUNCTION__, rc);
goto out;
}
fprintf(stderr, "return from util_thread2 rc=%d\n", rc);
pthread_exit(NULL);
fprintf(stderr, "%s: ERROR: Returned from switch_ctx (%d)\n", __FUNCTION__, rc);
rc = -EINVAL;
out:
if (uti_desc != (void*)-1 && uti_desc->wp != (void*)-1)
#ifdef POSTK_DEBUG_ARCH_DEP_35
munmap(uti_desc->wp, page_size * 3);
#else /* POSTK_DEBUG_ARCH_DEP_35 */
munmap(uti_desc->wp, PAGE_SIZE * 3);
#endif /* POSTK_DEBUG_ARCH_DEP_35 */
return rc;
}
@@ -4078,10 +4037,8 @@ return_execve2:
w.sr.args[2], w.sr.args[3], w.sr.args[4]);
}
else {
ret = munmap((void *)w.sr.args[1],
w.sr.args[2]);
if (ret == -1)
ret = -errno;
__eprintf("__NR_sched_setaffinity: invalid argument (%lx)\n", w.sr.args[0]);
ret = -EINVAL;
}
do_syscall_return(fd, cpu, ret, 0, 0, 0, 0);
break;

63
executer/user/syscall_intercept.c
View File

@@ -24,6 +24,7 @@ hook(long syscall_number,
int tid = uti_syscall0(__NR_gettid);
struct terminate_thread_desc term_desc;
unsigned long code;
int stack_top;
if (!uti_desc.start_syscall_intercept) {
return 1; /* System call isn't taken over */
@@ -50,34 +51,40 @@ hook(long syscall_number,
case __NR_munmap:
case __NR_mprotect:
case __NR_mremap:
if (!uti_desc.syscall_param_top) {
/* Overflow check */
if (uti_desc.syscall_stack_top == -1) {
*result = -ENOMEM;
return 0;
}
else {
/* Pop syscall_struct list for reentrant safety */
uti_desc.syscall_param = uti_desc.syscall_param_top;
uti_desc.syscall_param_top = *(void **)uti_desc.syscall_param;
uti_desc.syscall_param->number = syscall_number;
uti_desc.syscall_param->args[0] = arg0;
uti_desc.syscall_param->args[1] = arg1;
uti_desc.syscall_param->args[2] = arg2;
uti_desc.syscall_param->args[3] = arg3;
uti_desc.syscall_param->args[4] = arg4;
uti_desc.syscall_param->args[5] = arg5;
uti_desc.syscall_param->uti_clv = uti_desc.uti_clv;
uti_desc.syscall_param->ret = -EINVAL;
uti_syscall3(__NR_ioctl, uti_desc.fd, MCEXEC_UP_SYSCALL_THREAD, (long)uti_desc.syscall_param);
*result = uti_desc.syscall_param->ret;
/* push syscall_struct list */
*(void **)uti_desc.syscall_param = uti_desc.syscall_param_top;
uti_desc.syscall_param_top = uti_desc.syscall_param;
return 0; /* System call is taken over */
/* Sanity check */
if (uti_desc.syscall_stack_top < 0 || uti_desc.syscall_stack_top >= UTI_SZ_SYSCALL_STACK) {
*result = -EINVAL;
return 0;
}
break;
/* Store the return value in the stack to prevent it from getting corrupted
when an interrupt happens just after ioctl() and before copying the return
value to *result */
stack_top = __sync_fetch_and_sub(&uti_desc.syscall_stack_top, 1);
uti_desc.syscall_stack[stack_top].number = syscall_number;
uti_desc.syscall_stack[stack_top].args[0] = arg0;
uti_desc.syscall_stack[stack_top].args[1] = arg1;
uti_desc.syscall_stack[stack_top].args[2] = arg2;
uti_desc.syscall_stack[stack_top].args[3] = arg3;
uti_desc.syscall_stack[stack_top].args[4] = arg4;
uti_desc.syscall_stack[stack_top].args[5] = arg5;
uti_desc.syscall_stack[stack_top].uti_clv = uti_desc.uti_clv;
uti_desc.syscall_stack[stack_top].ret = -EINVAL;
uti_syscall3(__NR_ioctl, uti_desc.fd, MCEXEC_UP_SYSCALL_THREAD, (long)(uti_desc.syscall_stack + stack_top));
*result = uti_desc.syscall_stack[stack_top].ret;
/* push syscall_struct list */
__sync_fetch_and_add(&uti_desc.syscall_stack_top, 1);
return 0; /* System call is taken over */
case __NR_exit_group:
code = 0x100000000;
goto make_remote_thread_exit;
@@ -116,9 +123,13 @@ hook(long syscall_number,
static __attribute__((constructor)) void
init(void)
{
// Set up the callback function
/* Set up the callback function */
intercept_hook_point = hook;
/* Initialize uti_desc */
uti_desc.syscall_stack_top = UTI_SZ_SYSCALL_STACK - 1;
/* Pass address of uti_desc to McKernel */
uti_syscall1(733, (unsigned long)&uti_desc);
}