modify page_fault_process()

- change its argument from 'struct process *'
                        to 'struct process_vm *'.
- change its name from 'page_fault_process()'
                    to 'page_fault_process_vm()'.
- allow to resolve a fault on the process_vm of another process.

kernel/include/process.h

@@ -450,7 +450,8 @@ struct vm_range *previous_process_memory_range(
 int extend_up_process_memory_range(struct process_vm *vm,
 		struct vm_range *range, uintptr_t newend);
 
-int page_fault_process(struct process *proc, void *fault_addr, uint64_t reason);
+int page_fault_process_vm(struct process_vm *fault_vm, void *fault_addr,
+		uint64_t reason);
 int remove_process_region(struct process *proc,
                           unsigned long start, unsigned long end);
 struct program_load_desc;

kernel/mem.c

@@ -370,12 +370,12 @@ static void page_fault_handler(void *fault_addr, uint64_t reason, void *regs)
 	dkprintf("[%d]page_fault_handler(%p,%lx,%p)\n",
 			ihk_mc_get_processor_id(), fault_addr, reason, regs);
 
-	error = page_fault_process(proc, fault_addr, reason);
+	error = page_fault_process_vm(proc->vm, fault_addr, reason);
 	if (error) {
 		struct siginfo info;
 
 		kprintf("[%d]page_fault_handler(%p,%lx,%p):"
-				"fault proc failed. %d\n",
+				"fault vm failed. %d\n",
 				ihk_mc_get_processor_id(), fault_addr,
 				reason, regs, error);
 		unhandled_page_fault(proc, fault_addr, regs);

kernel/process.c

@@ -1491,24 +1491,23 @@ out:
 	return error;
 }
 
-static int do_page_fault_process(struct process *proc, void *fault_addr0, uint64_t reason)
+static int do_page_fault_process_vm(struct process_vm *vm, void *fault_addr0, uint64_t reason)
 {
-	struct process_vm *vm = proc->vm;
 	int error;
 	const uintptr_t fault_addr = (uintptr_t)fault_addr0;
 	struct vm_range *range;
 
-	dkprintf("[%d]do_page_fault_process(%p,%lx,%lx)\n",
+	dkprintf("[%d]do_page_fault_process_vm(%p,%lx,%lx)\n",
-			ihk_mc_get_processor_id(), proc, fault_addr0, reason);
+			ihk_mc_get_processor_id(), vm, fault_addr0, reason);
 
 	ihk_mc_spinlock_lock_noirq(&vm->memory_range_lock);
 
 	range = lookup_process_memory_range(vm, fault_addr, fault_addr+1);
 	if (range == NULL) {
 		error = -EFAULT;
-		kprintf("[%d]do_page_fault_process(%p,%lx,%lx):"
+		kprintf("[%d]do_page_fault_process_vm(%p,%lx,%lx):"
 				"out of range. %d\n",
-				ihk_mc_get_processor_id(), proc,
+				ihk_mc_get_processor_id(), vm,
 				fault_addr0, reason, error);
 		goto out;
 	}
@@ -1519,9 +1518,9 @@ static int do_page_fault_process(struct process *proc, void *fault_addr0, uint64
 			|| ((reason & PF_INSTR)
 				&& !(range->flag & VR_PROT_EXEC))) {
 		error = -EFAULT;
-		kprintf("[%d]do_page_fault_process(%p,%lx,%lx):"
+		kprintf("[%d]do_page_fault_process_vm(%p,%lx,%lx):"
 				"access denied. %d\n",
-				ihk_mc_get_processor_id(), proc,
+				ihk_mc_get_processor_id(), vm,
 				fault_addr0, reason, error);
 		goto out;
 	}
@@ -1558,9 +1557,9 @@ static int do_page_fault_process(struct process *proc, void *fault_addr0, uint64
 		goto out;
 	}
 	if (error) {
-		kprintf("[%d]do_page_fault_process(%p,%lx,%lx):"
+		kprintf("[%d]do_page_fault_process_vm(%p,%lx,%lx):"
 				"fault range failed. %d\n",
-				ihk_mc_get_processor_id(), proc,
+				ihk_mc_get_processor_id(), vm,
 				fault_addr0, reason, error);
 		goto out;
 	}
@@ -1568,22 +1567,19 @@ static int do_page_fault_process(struct process *proc, void *fault_addr0, uint64
 	error = 0;
 out:
 	ihk_mc_spinlock_unlock_noirq(&vm->memory_range_lock);
-	dkprintf("[%d]do_page_fault_process(%p,%lx,%lx): %d\n",
+	dkprintf("[%d]do_page_fault_process_vm(%p,%lx,%lx): %d\n",
-			ihk_mc_get_processor_id(), proc, fault_addr0,
+			ihk_mc_get_processor_id(), vm, fault_addr0,
 			reason, error);
 	return error;
 }
 
-int page_fault_process(struct process *proc, void *fault_addr, uint64_t reason)
+int page_fault_process_vm(struct process_vm *fault_vm, void *fault_addr, uint64_t reason)
 {
 	int error;
-
+	struct process *proc = cpu_local_var(current);
-	if (proc != cpu_local_var(current)) {
-		panic("page_fault_process: other process");
-	}
 
 	for (;;) {
-		error = do_page_fault_process(proc, fault_addr, reason);
+		error = do_page_fault_process_vm(fault_vm, fault_addr, reason);
 		if (error != -ERESTART) {
 			break;
 		}
@@ -1914,9 +1910,9 @@ int populate_process_memory(struct process *proc, void *start, size_t len)
 
 	end = (uintptr_t)start + len;
 	for (addr = (uintptr_t)start; addr < end; addr += PAGE_SIZE) {
-		error = page_fault_process(proc, (void *)addr, reason);
+		error = page_fault_process_vm(proc->vm, (void *)addr, reason);
 		if (error) {
-			ekprintf("populate_process_range:page_fault_process"
+			ekprintf("populate_process_range:page_fault_process_vm"
 					"(%p,%lx,%lx) failed %d\n",
 					proc, addr, reason, error);
 			goto out;

kernel/syscall.c

@@ -226,7 +226,7 @@ long do_syscall(struct syscall_request *req, int cpu, int pid)
 		if (res->status == STATUS_PAGE_FAULT) {
 			dkprintf("STATUS_PAGE_FAULT in syscall, pid: %d\n", 
 					cpu_local_var(current)->ftn->pid);
-			error = page_fault_process(get_cpu_local_var(cpu)->current,
+			error = page_fault_process_vm(proc->vm,
 					(void *)res->fault_address,
 					res->fault_reason|PF_POPULATE);