meta: rename kernel to Magenta

whether a mapping is private or shared determines how the mapping is handled
when a task is duplicated.

CMakeLists.txt

@@ -1,5 +1,5 @@
-cmake_minimum_required(VERSION 4.0)
-project(mango C ASM)
+cmake_minimum_required(VERSION 3.31)
+project(magenta C ASM)
 
 if (NOT BUILD_TOOLS_DIR)
 	message(FATAL_ERROR "No build tools directory specified. Please run build.sh")
@@ -9,8 +9,8 @@ set(CMAKE_C_STANDARD 17)
 
 set(kernel_arch x86_64)
 
-set(kernel_name "Mango")
-set(kernel_exe_name "mango_kernel")
+set(kernel_name "Magenta")
+set(kernel_exe_name "magenta_kernel")
 
 set(generic_src_dirs ds init kernel libc sched util vm syscall)
 set(kernel_sources "")
@@ -38,7 +38,7 @@ add_executable(${kernel_exe_name}
 target_include_directories(${kernel_exe_name} PRIVATE
 	include
 	libc/include
-	libmango/include
+	libmagenta/include
 	arch/${kernel_arch}/include)
 target_compile_options(${kernel_exe_name} PRIVATE
 	-nostdlib -ffreestanding

README

@@ -1,4 +1,4 @@
-Mango
+Magenta
 =====
 
 It's a kernel!

arch/user/include/mango/machine/cpu.h

@@ -1,5 +1,5 @@
-#ifndef MANGO_USER_CPU_H_
-#define MANGO_USER_CPU_H_
+#ifndef MAGENTA_USER_CPU_H_
+#define MAGENTA_USER_CPU_H_
 
 #ifdef __cplusplus
 extern "C" {

arch/user/include/mango/machine/hwlock.h

@@ -1,5 +1,5 @@
-#ifndef MANGO_USER_HWLOCK_H_
-#define MANGO_USER_HWLOCK_H_
+#ifndef MAGENTA_USER_HWLOCK_H_
+#define MAGENTA_USER_HWLOCK_H_
 
 #define ML_HWLOCK_INIT (0)
 

arch/user/include/mango/machine/init.h

@@ -1,5 +1,5 @@
-#ifndef MANGO_X86_64_INIT_H_
-#define MANGO_X86_64_INIT_H_
+#ifndef MAGENTA_X86_64_INIT_H_
+#define MAGENTA_X86_64_INIT_H_
 
 #include <stddef.h>
 #include <stdint.h>

arch/user/include/mango/machine/irq.h

@@ -1,5 +1,5 @@
-#ifndef MANGO_X86_64_IRQ_H_
-#define MANGO_X86_64_IRQ_H_
+#ifndef MAGENTA_X86_64_IRQ_H_
+#define MAGENTA_X86_64_IRQ_H_
 
 
 #endif

arch/user/include/mango/machine/pmap.h

@@ -1,5 +1,5 @@
-#ifndef MANGO_USER_PMAP_H_
-#define MANGO_USER_PMAP_H_
+#ifndef MAGENTA_USER_PMAP_H_
+#define MAGENTA_USER_PMAP_H_
 
 #include <stdint.h>
 

arch/user/include/mango/machine/vm.h

@@ -1,5 +1,5 @@
-#ifndef MANGO_USER_VM_H_
-#define MANGO_USER_VM_H_
+#ifndef MAGENTA_USER_VM_H_
+#define MAGENTA_USER_VM_H_
 
 #include <stdint.h>
 

arch/x86_64/include/kernel/machine/thread.h

@@ -34,7 +34,9 @@ extern kern_status_t ml_thread_prepare_user_context(
 /* prepare the stack so that ml_thread_switch_user can jump to usermode
  * with the specified register context */
 extern kern_status_t ml_thread_clone_user_context(
-	const struct ml_cpu_context *ctx,
+	const struct ml_cpu_context *src_regs,
+	const struct ml_thread *src_ml,
+	struct ml_thread *dest_ml,
 	uintptr_t return_value,
 	virt_addr_t *kernel_sp);
 

arch/x86_64/init.c

@@ -20,7 +20,7 @@
 #include <kernel/util.h>
 #include <kernel/vm.h>
 
-#undef HARDWARE_RNG
+#define HARDWARE_RNG
 
 #define PTR32(x)            ((void *)((uintptr_t)(x)))
 

arch/x86_64/irq.c

@@ -217,6 +217,12 @@ void irq_dispatch(struct ml_cpu_context *regs)
 
 void syscall_dispatch(struct ml_cpu_context *regs)
 {
+	struct thread *thr = get_current_thread();
+	if (thr) {
+		thr->tr_irqctx = regs;
+		put_current_thread(thr);
+	}
+
 	unsigned int sysid = regs->rax;
 	virt_addr_t syscall_impl = syscall_get_function(sysid);
 

arch/x86_64/pmap.c

@@ -9,7 +9,7 @@
 #include <kernel/types.h>
 #include <kernel/vm-object.h>
 #include <kernel/vm.h>
-#include <mango/status.h>
+#include <magenta/status.h>
 
 /* some helpful datasize constants */
 #define C_1GiB          0x40000000ULL
@@ -196,15 +196,15 @@ kern_status_t pmap_get(
 		}
 
 		if (pte & PTE_RW) {
-			*out_pfn |= (VM_PROT_READ | VM_PROT_WRITE);
+			*out_prot |= (VM_PROT_READ | VM_PROT_WRITE);
 		}
 
 		if (pte & PTE_USR) {
-			*out_pfn |= VM_PROT_USER;
+			*out_prot |= VM_PROT_USER;
 		}
 
 		if (!(pte & PTE_NX)) {
-			*out_pfn |= VM_PROT_EXEC;
+			*out_prot |= VM_PROT_EXEC;
 		}
 	}
 
@@ -321,6 +321,10 @@ static kern_status_t do_pmap_remove(
 	virt_addr_t pv,
 	enum page_size size)
 {
+	if (pmap == PMAP_INVALID) {
+		return KERN_OK;
+	}
+
 	unsigned int pml4t_index = BAD_INDEX, pdpt_index = BAD_INDEX,
 		     pd_index = BAD_INDEX, pt_index = BAD_INDEX;
 
@@ -622,5 +626,13 @@ kern_status_t pmap_remove(pmap_t pmap, virt_addr_t p)
 
 kern_status_t pmap_remove_range(pmap_t pmap, virt_addr_t p, size_t len)
 {
+	if (pmap == PMAP_INVALID) {
+		return KERN_OK;
+	}
+
+	for (size_t i = p; i < p + len; i += VM_PAGE_SIZE) {
+		pmap_remove(pmap, i);
+	}
+
 	return KERN_OK;
 }

arch/x86_64/pmap_ctrl.S

@@ -1,3 +1,11 @@
+	.global pmap_flush
+	.type pmap_flush, @function
+
+pmap_flush:
+	mov %cr3, %rax
+	mov %rax, %cr3
+	ret
+
 
 	.global pmap_switch
 	.type pmap_switch, @function
@@ -6,6 +14,7 @@ pmap_switch:
 	mov %rdi, %cr3
 	ret
 
+
 	.global gigabyte_pages
 	.type gigabyte_pages, @function
 

arch/x86_64/serial.c

@@ -28,6 +28,10 @@ void serial_send_byte(int device, char out)
 
 	outportb(device, out);
 
+	if (device == COM1) {
+		outportb(0xe9, out);
+	}
+
 	while (!transmit_empty(device)) {
 		_count++;
 	}

arch/x86_64/thread.c

@@ -81,16 +81,21 @@ extern kern_status_t ml_thread_prepare_user_context(
 }
 
 kern_status_t ml_thread_clone_user_context(
-	const struct ml_cpu_context *src_ctx,
+	const struct ml_cpu_context *src_regs,
+	const struct ml_thread *src_ml,
+	struct ml_thread *dest_ml,
 	uintptr_t return_value,
 	virt_addr_t *kernel_sp)
 {
 	(*kernel_sp) -= sizeof(struct ml_cpu_context);
 
-	struct ml_cpu_context *ctx = (struct ml_cpu_context *)(*kernel_sp);
-	memcpy(ctx, src_ctx, sizeof *ctx);
+	struct ml_cpu_context *regs = (struct ml_cpu_context *)(*kernel_sp);
+	memcpy(regs, src_regs, sizeof *regs);
 
-	ctx->rax = return_value;
+	regs->rax = return_value;
+
+	dest_ml->tr_fsbase = src_ml->tr_fsbase;
+	dest_ml->tr_gsbase = src_ml->tr_gsbase;
 
 	return KERN_OK;
 }

arch/x86_64/toolchain.cmake

@@ -1,5 +1,5 @@
 # the name of the target operating system
-set(CMAKE_SYSTEM_NAME Mango)
+set(CMAKE_SYSTEM_NAME Magenta)
 
 # which compilers to use for C and C++
 set(CMAKE_C_COMPILER   x86_64-elf-gcc)

include/kernel/address-space.h

@@ -22,6 +22,8 @@ struct vm_area {
 	struct address_space *vma_space;
 	/* used to link to vm_object->vo_mappings */
 	struct queue_entry vma_object_entry;
+	/* the memory control flags applied to this area */
+	vm_flags_t vma_flags;
 	/* the memory protection flags applied to this area */
 	vm_prot_t vma_prot;
 	/* offset in bytes to the start of the object data that was mapped */
@@ -83,6 +85,7 @@ extern kern_status_t address_space_map(
 	struct vm_object *object,
 	off_t object_offset,
 	size_t length,
+	vm_flags_t flags,
 	vm_prot_t prot,
 	virt_addr_t *out);
 extern kern_status_t address_space_unmap(

include/kernel/arg.h

@@ -1,7 +1,7 @@
 #ifndef KERNEL_ARG_H_
 #define KERNEL_ARG_H_
 
-#include <mango/types.h>
+#include <magenta/types.h>
 #include <stdbool.h>
 
 #define CMDLINE_MAX 4096

include/kernel/bsp.h

@@ -2,7 +2,7 @@
 #define KERNEL_BSP_H_
 
 #include <kernel/compiler.h>
-#include <mango/status.h>
+#include <magenta/status.h>
 #include <kernel/types.h>
 #include <stddef.h>
 #include <stdint.h>

include/kernel/console.h

@@ -16,8 +16,8 @@
 */
 #include <kernel/locks.h>
 #include <kernel/queue.h>
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 
 #ifdef __cplusplus
 extern "C" {

include/kernel/equeue.h

@@ -4,7 +4,7 @@
 #include <kernel/locks.h>
 #include <kernel/object.h>
 #include <kernel/sched.h>
-#include <mango/types.h>
+#include <magenta/types.h>
 
 #define EQUEUE_PACKET_MAX 100
 

include/kernel/futex.h

@@ -3,7 +3,7 @@
 
 #include <kernel/btree.h>
 #include <kernel/wait.h>
-#include <mango/types.h>
+#include <magenta/types.h>
 
 struct task;
 struct address_space;

include/kernel/handle.h

@@ -2,8 +2,8 @@
 #define KERNEL_HANDLE_H_
 
 #include <kernel/bitmap.h>
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 #include <stddef.h>
 #include <stdint.h>
 
@@ -44,6 +44,9 @@ struct handle_table {
 
 extern struct handle_table *handle_table_create(void);
 extern void handle_table_destroy(struct handle_table *tab);
+extern kern_status_t handle_table_duplicate(
+	struct handle_table *src,
+	struct handle_table **dest);
 
 extern kern_status_t handle_table_alloc_handle(
 	struct handle_table *tab,

include/kernel/iovec.h

@@ -1,7 +1,7 @@
 #ifndef KERNEL_IOVEC_H_
 #define KERNEL_IOVEC_H_
 
-#include <mango/types.h>
+#include <magenta/types.h>
 #include <stddef.h>
 
 struct address_space;

include/kernel/msg.h

@@ -3,8 +3,8 @@
 
 #include <kernel/btree.h>
 #include <kernel/locks.h>
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 
 struct port;
 struct thread;

include/kernel/object.h

@@ -5,7 +5,7 @@
 #include <kernel/locks.h>
 #include <kernel/vm.h>
 #include <kernel/wait.h>
-#include <mango/status.h>
+#include <magenta/status.h>
 #include <stddef.h>
 
 #ifdef __cplusplus
@@ -65,7 +65,7 @@ extern "C" {
 #define OBJECT_PATH_MAX 256
 
 #define OBJECT_CAST(to_type, to_type_member, p)                                \
-	((to_type *)((uintptr_t)p) - offsetof(to_type, to_type_member))
+	((to_type *)(((uintptr_t)p) - offsetof(to_type, to_type_member)))
 #define OBJECT_C_CAST(c_type, c_type_member, obj_type, objp)                   \
 	OBJECT_IS_TYPE(objp, obj_type)                                         \
 	? OBJECT_CAST(c_type, c_type_member, (objp)) : NULL

include/kernel/percpu.h

@@ -1,7 +1,7 @@
 #ifndef KERNEL_PERCPU_H_
 #define KERNEL_PERCPU_H_
 
-#include <mango/status.h>
+#include <magenta/status.h>
 #include <kernel/compiler.h>
 #include <kernel/sched.h>
 

include/kernel/pmap.h

@@ -5,7 +5,7 @@
 
 #include <kernel/machine/pmap.h>
 #include <kernel/vm.h>
-#include <mango/status.h>
+#include <magenta/status.h>
 #include <stddef.h>
 
 #define PMAP_INVALID ML_PMAP_INVALID
@@ -52,6 +52,10 @@ extern pmap_t pmap_create(void);
 extern void pmap_destroy(pmap_t pmap);
 extern void pmap_switch(pmap_t pmap);
 
+extern void pmap_flush(void);
+extern void pmap_flush_page(virt_addr_t p);
+extern void pmap_flush_range(virt_addr_t start, size_t length);
+
 extern kern_status_t pmap_handle_fault(
 	virt_addr_t fault_addr,
 	enum pmap_fault_flags flags);

include/kernel/sched.h

@@ -6,7 +6,7 @@
 #include <kernel/locks.h>
 #include <kernel/queue.h>
 #include <kernel/types.h>
-#include <mango/status.h>
+#include <magenta/status.h>
 
 #define PRIO_MAX 32
 

include/kernel/syscall.h

@@ -5,8 +5,8 @@
 #include <kernel/handle.h>
 #include <kernel/task.h>
 #include <kernel/vm.h>
-#include <mango/status.h>
-#include <mango/syscall.h>
+#include <magenta/status.h>
+#include <magenta/syscall.h>
 
 #define validate_access(task, ptr, len, flags)                                 \
 	__validate_access(task, (const void *)ptr, len, flags)
@@ -42,6 +42,7 @@ extern kern_status_t sys_task_exit(int status);
 extern kern_status_t sys_task_self(kern_handle_t *out);
 extern kern_status_t sys_task_create(
 	kern_handle_t parent_handle,
+	task_flags_t flags,
 	const char *name,
 	size_t name_len,
 	kern_handle_t *out_task,
@@ -128,6 +129,7 @@ extern kern_status_t sys_address_space_map(
 	kern_handle_t object,
 	off_t object_offset,
 	size_t length,
+	vm_flags_t flags,
 	vm_prot_t prot,
 	virt_addr_t *out_base_address);
 extern kern_status_t sys_address_space_unmap(
@@ -211,7 +213,7 @@ extern kern_status_t sys_kern_object_query(
 extern kern_status_t sys_vm_controller_create(kern_handle_t *out);
 extern kern_status_t sys_vm_controller_recv(
 	kern_handle_t ctrl,
-	equeue_packet_page_request_t *out);
+	equeue_packet_vm_request_t *out);
 extern kern_status_t sys_vm_controller_recv_async(
 	kern_handle_t ctrl,
 	kern_handle_t eq,
@@ -224,6 +226,14 @@ extern kern_status_t sys_vm_controller_create_object(
 	size_t data_len,
 	vm_prot_t prot,
 	kern_handle_t *out);
+extern kern_status_t sys_vm_controller_prepare_attach(
+	kern_handle_t ctrl,
+	uint64_t req_id,
+	kern_handle_t *out_vmo);
+extern kern_status_t sys_vm_controller_finish_attach(
+	kern_handle_t ctrl,
+	uint64_t req_id,
+	equeue_key_t new_key);
 extern kern_status_t sys_vm_controller_detach_object(
 	kern_handle_t ctrl,
 	kern_handle_t vmo);

include/kernel/task.h

@@ -39,7 +39,11 @@ struct task {
 
 extern struct task *task_alloc(void);
 extern struct task *task_cast(struct object *obj);
-extern struct task *task_create(const char *name, size_t name_len);
+extern struct task *task_create(
+	struct task *parent,
+	task_flags_t flags,
+	const char *name,
+	size_t name_len);
 static inline struct task *task_ref(struct task *task)
 {
 	return OBJECT_CAST(struct task, t_base, object_ref(&task->t_base));
@@ -66,6 +70,16 @@ extern kern_status_t task_resolve_handle(
 	kern_handle_t handle,
 	struct object **out_obj,
 	handle_flags_t *out_flags);
+extern kern_status_t task_config_get(
+	struct task *task,
+	kern_config_key_t key,
+	void *out,
+	size_t max);
+extern kern_status_t task_config_set(
+	struct task *task,
+	kern_config_key_t key,
+	const void *ptr,
+	size_t len);
 extern kern_status_t task_close_handle(struct task *task, kern_handle_t handle);
 extern struct thread *task_create_thread(struct task *parent);
 extern struct task *kernel_task(void);

include/kernel/types.h

@@ -1,7 +1,7 @@
 #ifndef KERNEL_TYPES_H_
 #define KERNEL_TYPES_H_
 
-#include <mango/types.h>
+#include <magenta/types.h>
 #include <stddef.h>
 #include <stdint.h>
 

include/kernel/util.h

@@ -1,7 +1,7 @@
 #ifndef KERNEL_UTIL_H_
 #define KERNEL_UTIL_H_
 
-#include <mango/types.h>
+#include <magenta/types.h>
 #include <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>

include/kernel/vm-controller.h

@@ -3,40 +3,41 @@
 
 #include <kernel/locks.h>
 #include <kernel/object.h>
-#include <mango/types.h>
+#include <magenta/types.h>
 
 struct thread;
 struct equeue;
 struct vm_object;
 
-enum page_request_status {
-	PAGE_REQUEST_PENDING = 0,
-	PAGE_REQUEST_IN_PROGRESS,
-	PAGE_REQUEST_COMPLETE,
-	PAGE_REQUEST_ASYNC,
+enum vm_request_status {
+	VM_REQUEST_PENDING = 0,
+	VM_REQUEST_IN_PROGRESS,
+	VM_REQUEST_COMPLETE,
+	VM_REQUEST_ASYNC,
 };
 
 struct vm_controller {
 	struct object vc_base;
-	/* tree of pending page requests */
+	/* tree of pending vm requests */
 	struct btree vc_requests;
-	/* the equeue to send async page requests to */
 	struct equeue *vc_eq;
 	equeue_key_t vc_eq_key;
-	/* the number of page requests queued with status PAGE_REQUEST_PENDING.
+	/* the number of page requests queued with status VM_REQUEST_PENDING.
 	 * used to assert/clear VM_CONTROLLER_SIGNAL_REQUEST_RECEIVED */
 	size_t vc_requests_waiting;
 };
 
-struct page_request {
+struct vm_request {
 	uint64_t req_id;
 	unsigned int req_type;
-	enum page_request_status req_status;
+	enum vm_request_status req_status;
 	kern_status_t req_result;
 	spin_lock_t req_lock;
-	equeue_key_t req_object;
+	struct vm_object *req_object;
 	struct thread *req_sender;
+	/* this node is added to vm-controller vc_requests list */
 	struct btree_node req_node;
+	/* these values are used for VM_REQUEST_READ and VM_REQUEST_DIRTY */
 	off_t req_offset;
 	size_t req_length;
 };
@@ -48,7 +49,7 @@ extern struct vm_controller *vm_controller_create(void);
 
 extern kern_status_t vm_controller_recv(
 	struct vm_controller *ctrl,
-	equeue_packet_page_request_t *out);
+	equeue_packet_vm_request_t *out);
 extern kern_status_t vm_controller_recv_async(
 	struct vm_controller *ctrl,
 	struct equeue *eq,
@@ -62,6 +63,14 @@ extern kern_status_t vm_controller_create_object(
 	size_t data_len,
 	vm_prot_t prot,
 	struct vm_object **out);
+extern kern_status_t vm_controller_prepare_attach(
+	struct vm_controller *ctrl,
+	uint64_t req_id,
+	struct vm_object **out_vmo);
+extern kern_status_t vm_controller_finish_attach(
+	struct vm_controller *ctrl,
+	uint64_t req_id,
+	equeue_key_t new_key);
 extern kern_status_t vm_controller_detach_object(
 	struct vm_controller *ctrl,
 	struct vm_object *vmo);
@@ -72,10 +81,16 @@ extern kern_status_t vm_controller_supply_pages(
 	struct vm_object *src,
 	off_t src_offset,
 	size_t count);
+extern void vm_controller_fulfill_requests(
+	struct vm_controller *ctrl,
+	equeue_key_t object,
+	off_t offset,
+	size_t length,
+	kern_status_t result);
 
 extern kern_status_t vm_controller_send_request(
 	struct vm_controller *ctrl,
-	struct page_request *req,
+	struct vm_request *req,
 	unsigned long *irq_flags);
 
 DEFINE_OBJECT_LOCK_FUNCTION(vm_controller, vc_base)

include/kernel/vm-object.h

@@ -20,19 +20,25 @@ enum vm_object_flags {
 	 * be detached, allowing the server to close the last handle to the
 	 * object and dispose of it. */
 	VMO_AUTO_DETACH = 0x04u,
+	/* this vmo is a duplicate of a vmo that is attached to a vm-controller.
+	 * the duplicate vmo is scheduled to be attached to the same controller,
+	 * but this won't actually happen until the controller is needed to
+	 * fulfill a page request. once the duplicate vmo has been attached to
+	 * the controller, this flag will be cleared. */
+	VMO_LAZY_ATTACH = 0x08u,
 
 	/* these flags are for use with vm_object_get_page */
 	/**************************************************/
 
 	/* if the relevant page hasn't been allocated yet, it will be allocated
 	 * and returned. if this flag isn't specified, NULL will be returned. */
-	VMO_ALLOCATE_MISSING_PAGE = 0x08u,
+	VMO_ALLOCATE_MISSING_PAGE = 0x0100u,
 	/* if the vm-object is attached to a vm-controller, and the relevant
 	 * page is uncommitted, send a request to the vm-controller to provide
 	 * the missing page. will result in the vm-object being unlocked and
 	 * the current thread sleeping until the request is fulfilled. the
 	 * vm-object will be re-locked before the function returns. */
-	VMO_REQUEST_MISSING_PAGE = 0x10u,
+	VMO_REQUEST_MISSING_PAGE = 0x0200u,
 };
 
 struct vm_object {
@@ -86,6 +92,21 @@ extern struct vm_object *vm_object_create_in_place(
 
 /* create a copy-on-write duplicate of a vm-object */
 extern struct vm_object *vm_object_duplicate_cow(struct vm_object *vmo);
+/* attach a copy-on-write duplicate of a vm-object to the vm-controller that
+ * controlled the original vm-object */
+extern kern_status_t vm_object_attach_cow(
+	struct vm_object *vmo,
+	unsigned long *irq_flags);
+
+/* prefetch any missing pages in the specified range of a vm-object.
+ * any lazy-allocated pages will be allocated.
+ * any missing pages will be requested from the vm-controller, if one is
+ * attached. */
+extern kern_status_t vm_object_prefetch(
+	struct vm_object *vo,
+	off_t offset,
+	size_t length,
+	unsigned long *irq_flags);
 
 extern struct vm_page *vm_object_get_page(
 	struct vm_object *vo,

include/kernel/vm.h

@@ -8,7 +8,7 @@
 #include <kernel/machine/vm.h>
 #include <kernel/queue.h>
 #include <kernel/types.h>
-#include <mango/status.h>
+#include <magenta/status.h>
 #include <stddef.h>
 
 #ifdef __cplusplus

init/main.c

@@ -23,7 +23,7 @@ extern char __pstart[], __pend[];
 
 void print_kernel_banner(void)
 {
-	printk("Mango kernel version " BUILD_ID);
+	printk("Magenta kernel version " BUILD_ID);
 }
 
 static void hang(void)
@@ -108,7 +108,8 @@ void kernel_init(uintptr_t arg)
 	       bsp.bsp_trailer.bsp_exec_entry,
 	       bsp.bsp_vmo);
 
-	struct task *bootstrap_task = task_create("bootstrap", 9);
+	struct task *bootstrap_task
+		= task_create(NULL, TASK_F_DEFAULT, "bootstrap", 9);
 	tracek("created bootstrap task (pid=%u)", bootstrap_task->t_id);
 
 	status = bsp_launch_async(&bsp, bootstrap_task);

kernel/arg.c

@@ -1,7 +1,7 @@
 #include <kernel/arg.h>
 #include <kernel/libc/ctype.h>
 #include <kernel/libc/string.h>
-#include <mango/status.h>
+#include <magenta/status.h>
 
 static char g_cmdline[CMDLINE_MAX + 1] = {0};
 

kernel/bsp.c

@@ -120,6 +120,7 @@ static kern_status_t map_executable_exec(
 		bsp->bsp_vmo,
 		text_foffset,
 		bsp->bsp_trailer.bsp_text_size,
+		VM_SHARED,
 		VM_PROT_READ | VM_PROT_EXEC | VM_PROT_USER,
 		&text_base);
 	if (status != KERN_OK) {
@@ -132,6 +133,7 @@ static kern_status_t map_executable_exec(
 		data,
 		data_foffset,
 		bsp->bsp_trailer.bsp_data_size,
+		VM_PRIVATE,
 		VM_PROT_READ | VM_PROT_WRITE | VM_PROT_USER,
 		&data_base);
 	if (status != KERN_OK) {
@@ -165,6 +167,7 @@ kern_status_t bsp_launch_async(struct bsp *bsp, struct task *task)
 		user_stack,
 		0,
 		BOOTSTRAP_STACK_SIZE,
+		VM_PRIVATE,
 		VM_PROT_READ | VM_PROT_WRITE | VM_PROT_USER,
 		&stack_buffer);
 
@@ -178,6 +181,7 @@ kern_status_t bsp_launch_async(struct bsp *bsp, struct task *task)
 		bsp->bsp_vmo,
 		0,
 		bsp->bsp_trailer.bsp_exec_offset,
+		VM_PRIVATE,
 		VM_PROT_READ | VM_PROT_USER,
 		&bsp_data_base);
 

kernel/channel.c

@@ -6,7 +6,7 @@
 #include <kernel/task.h>
 #include <kernel/thread.h>
 #include <kernel/util.h>
-#include <mango/signal.h>
+#include <magenta/signal.h>
 
 #define CHANNEL_CAST(p) OBJECT_C_CAST(struct channel, c_base, &channel_type, p)
 

kernel/futex.c

@@ -2,7 +2,7 @@
 #include <kernel/futex.h>
 #include <kernel/sched.h>
 #include <kernel/task.h>
-#include <mango/status.h>
+#include <magenta/status.h>
 
 #define FUTEX_CREATE 0x40u
 

kernel/handle.c

@@ -5,7 +5,7 @@
 #include <kernel/sched.h>
 #include <kernel/util.h>
 #include <kernel/vm.h>
-#include <mango/types.h>
+#include <magenta/types.h>
 
 /* depth=3 gives a maximum of ~66.6 million handles */
 #define MAX_TABLE_DEPTH  3
@@ -77,6 +77,81 @@ void handle_table_destroy(struct handle_table *tab)
 	do_handle_table_destroy(tab, 0);
 }
 
+static kern_status_t do_handle_table_duplicate_leaf(
+	struct handle_table *src,
+	struct handle_table **dest)
+{
+	struct handle_table *out
+		= vm_cache_alloc(&handle_table_cache, VM_NORMAL);
+	if (!out) {
+		return KERN_NO_MEMORY;
+	}
+
+	memcpy(out, src, sizeof *out);
+
+	for (size_t i = 0; i < HANDLES_PER_TABLE; i++) {
+		struct object *obj = src->t_handles.t_handle_list[i].h_object;
+		if (obj) {
+			object_ref(obj);
+		}
+	}
+
+	*dest = out;
+	return KERN_OK;
+}
+
+static kern_status_t do_handle_table_duplicate(
+	struct handle_table *src,
+	struct handle_table **dest,
+	unsigned int depth)
+{
+	if (depth == MAX_TABLE_DEPTH - 1) {
+		return do_handle_table_duplicate_leaf(src, dest);
+	}
+
+	struct handle_table *out
+		= vm_cache_alloc(&handle_table_cache, VM_NORMAL);
+	if (!out) {
+		return KERN_NO_MEMORY;
+	}
+
+	memcpy(out->t_subtables.t_subtable_map,
+	       src->t_subtables.t_subtable_map,
+	       sizeof out->t_subtables.t_subtable_map);
+	memset(out->t_subtables.t_subtable_list,
+	       0x0,
+	       sizeof out->t_subtables.t_subtable_list);
+
+	for (size_t i = 0; i < REFS_PER_TABLE; i++) {
+		struct handle_table *child
+			= src->t_subtables.t_subtable_list[i];
+		struct handle_table *dup = NULL;
+		kern_status_t status = KERN_OK;
+		if (child) {
+			status = do_handle_table_duplicate(
+				child,
+				&dup,
+				depth + 1);
+		}
+
+		if (status == KERN_OK) {
+			out->t_subtables.t_subtable_list[i] = dup;
+		} else {
+			return status;
+		}
+	}
+
+	*dest = out;
+	return KERN_OK;
+}
+
+kern_status_t handle_table_duplicate(
+	struct handle_table *src,
+	struct handle_table **dest)
+{
+	return do_handle_table_duplicate(src, dest, 0);
+}
+
 static kern_status_t decode_handle_indices(
 	kern_handle_t handle,
 	unsigned int indices[MAX_TABLE_DEPTH])

kernel/printk.c

@@ -98,9 +98,8 @@ int printk(const char *format, ...)
 	unsigned long flags;
 	spin_lock_irqsave(&log_buffer_lock, &flags);
 	save_log_message(msg);
-	spin_unlock_irqrestore(&log_buffer_lock, flags);
-
 	flush_log_buffer();
+	spin_unlock_irqrestore(&log_buffer_lock, flags);
 
 	return 0;
 }

kernel/status.c

@@ -1,5 +1,5 @@
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 
 #define ERROR_STRING_CASE(code)                                                \
 	case code:                                                             \

libmagenta/CMakeLists.txt

@@ -1,4 +1,4 @@
-file(GLOB headers ${CMAKE_CURRENT_SOURCE_DIR}/include/mango/*.h)
+file(GLOB headers ${CMAKE_CURRENT_SOURCE_DIR}/include/magenta/*.h)
 file(GLOB asm_sources
 	${CMAKE_CURRENT_SOURCE_DIR}/arch/${CMAKE_SYSTEM_PROCESSOR}/*.S)
 
@@ -6,7 +6,7 @@ set(public_include_dirs
 	${CMAKE_CURRENT_SOURCE_DIR}/include
 	${CMAKE_CURRENT_SOURCE_DIR}/include-user)
 
-add_library(libmango STATIC ${asm_sources})
-target_include_directories(libmango PUBLIC
+add_library(libmagenta STATIC ${asm_sources})
+target_include_directories(libmagenta PUBLIC
 	${CMAKE_CURRENT_SOURCE_DIR}/include
 	${CMAKE_CURRENT_SOURCE_DIR}/include-user)

libmagenta/arch/x86_64/syscall.S

@@ -1,4 +1,4 @@
-#include "mango/syscall.h"
+#include "magenta/syscall.h"
 
 # Registers:
 #  rax = syscall ID + return value
@@ -57,7 +57,7 @@
 
 SYSCALL_GATE task_exit SYS_TASK_EXIT 1
 SYSCALL_GATE task_self SYS_TASK_SELF 1
-SYSCALL_GATE task_create SYS_TASK_CREATE 5
+SYSCALL_GATE task_create SYS_TASK_CREATE 6
 SYSCALL_GATE task_duplicate SYS_TASK_DUPLICATE 2
 SYSCALL_GATE task_create_thread SYS_TASK_CREATE_THREAD 6
 SYSCALL_GATE task_get_address_space SYS_TASK_GET_ADDRESS_SPACE 1
@@ -77,7 +77,7 @@ SYSCALL_GATE vm_object_copy SYS_VM_OBJECT_COPY 6
 
 SYSCALL_GATE address_space_read SYS_ADDRESS_SPACE_READ 5
 SYSCALL_GATE address_space_write SYS_ADDRESS_SPACE_WRITE 5
-SYSCALL_GATE address_space_map SYS_ADDRESS_SPACE_MAP 7
+SYSCALL_GATE address_space_map SYS_ADDRESS_SPACE_MAP 8
 SYSCALL_GATE address_space_unmap SYS_ADDRESS_SPACE_UNMAP 3
 SYSCALL_GATE address_space_reserve SYS_ADDRESS_SPACE_RESERVE 4
 SYSCALL_GATE address_space_release SYS_ADDRESS_SPACE_RELEASE 3
@@ -102,6 +102,8 @@ SYSCALL_GATE vm_controller_create SYS_VM_CONTROLLER_CREATE 1
 SYSCALL_GATE vm_controller_recv SYS_VM_CONTROLLER_RECV 2
 SYSCALL_GATE vm_controller_recv_async SYS_VM_CONTROLLER_RECV_ASYNC 3
 SYSCALL_GATE vm_controller_create_object SYS_VM_CONTROLLER_CREATE_OBJECT 7
+SYSCALL_GATE vm_controller_prepare_attach SYS_VM_CONTROLLER_PREPARE_ATTACH 3
+SYSCALL_GATE vm_controller_finish_attach SYS_VM_CONTROLLER_FINISH_ATTACH 3
 SYSCALL_GATE vm_controller_detach_object SYS_VM_CONTROLLER_DETACH_OBJECT 2
 SYSCALL_GATE vm_controller_supply_pages SYS_VM_CONTROLLER_SUPPLY_PAGES 6
 

libmagenta/include-user/magenta/config.h

@@ -1,8 +1,8 @@
-#ifndef MANGO_CONFIG_H_
-#define MANGO_CONFIG_H_
+#ifndef MAGENTA_CONFIG_H_
+#define MAGENTA_CONFIG_H_
 
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 #include <stddef.h>
 
 extern kern_status_t kern_config_get(

libmagenta/include-user/magenta/equeue.h

@@ -1,7 +1,7 @@
-#ifndef MANGO_EQUEUE_H_
-#define MANGO_EQUEUE_H_
+#ifndef MAGENTA_EQUEUE_H_
+#define MAGENTA_EQUEUE_H_
 
-#include <mango/types.h>
+#include <magenta/types.h>
 
 extern kern_status_t equeue_create(kern_handle_t *out);
 extern kern_status_t equeue_dequeue(kern_handle_t eq, equeue_packet_t *out);

libmagenta/include-user/magenta/futex.h

@@ -1,8 +1,8 @@
-#ifndef MANGO_FUTEX_H_
-#define MANGO_FUTEX_H_
+#ifndef MAGENTA_FUTEX_H_
+#define MAGENTA_FUTEX_H_
 
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 
 extern kern_status_t futex_wait(
 	kern_futex_t *futex,

libmagenta/include-user/magenta/handle.h

@@ -1,8 +1,8 @@
-#ifndef MANGO_HANDLE_H_
-#define MANGO_HANDLE_H_
+#ifndef MAGENTA_HANDLE_H_
+#define MAGENTA_HANDLE_H_
 
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 
 extern kern_status_t kern_handle_close(kern_handle_t handle);
 extern kern_status_t kern_handle_transfer(

libmagenta/include-user/magenta/log.h

@@ -1,8 +1,8 @@
-#ifndef MANGO_LOG_H_
-#define MANGO_LOG_H_
+#ifndef MAGENTA_LOG_H_
+#define MAGENTA_LOG_H_
 
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 
 #undef TRACE
 

libmagenta/include-user/magenta/msg.h

@@ -1,8 +1,8 @@
-#ifndef MANGO_MSG_H_
-#define MANGO_MSG_H_
+#ifndef MAGENTA_MSG_H_
+#define MAGENTA_MSG_H_
 
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 
 extern kern_status_t channel_create(unsigned int id, kern_handle_t *out);
 extern kern_status_t port_create(kern_handle_t *out);

libmagenta/include-user/magenta/object.h

@@ -1,7 +1,7 @@
-#ifndef MANGO_OBJECT_H_
-#define MANGO_OBJECT_H_
+#ifndef MAGENTA_OBJECT_H_
+#define MAGENTA_OBJECT_H_
 
-#include <mango/types.h>
+#include <magenta/types.h>
 
 extern kern_status_t kern_object_wait(kern_wait_item_t *items, size_t nr_items);
 extern kern_status_t kern_object_query(

libmagenta/include-user/magenta/task.h

@@ -1,14 +1,15 @@
-#ifndef MANGO_TASK_H_
-#define MANGO_TASK_H_
+#ifndef MAGENTA_TASK_H_
+#define MAGENTA_TASK_H_
 
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 
 extern kern_status_t task_exit(int status);
 extern kern_status_t task_self(kern_handle_t *out);
 
 extern kern_status_t task_create(
 	kern_handle_t parent,
+	task_flags_t flags,
 	const char *name,
 	size_t name_len,
 	kern_handle_t *out_task,
@@ -36,6 +37,13 @@ extern kern_status_t task_config_set(
 extern kern_status_t task_duplicate(
 	kern_handle_t *out_task,
 	kern_handle_t *out_address_space);
+extern kern_status_t task_reset(
+	virt_addr_t ip,
+	virt_addr_t sp,
+	uintptr_t *args,
+	size_t nr_args,
+	virt_addr_t unmap_base,
+	size_t unmap_length);
 
 extern kern_status_t thread_self(kern_handle_t *out);
 extern kern_status_t thread_start(kern_handle_t thread);

libmagenta/include-user/magenta/vm.h

@@ -1,8 +1,8 @@
-#ifndef MANGO_VM_H_
-#define MANGO_VM_H_
+#ifndef MAGENTA_VM_H_
+#define MAGENTA_VM_H_
 
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 
 extern kern_status_t vm_object_create(
 	const char *name,
@@ -48,6 +48,7 @@ extern kern_status_t address_space_map(
 	kern_handle_t object,
 	off_t object_offset,
 	size_t length,
+	vm_flags_t flags,
 	vm_prot_t prot,
 	virt_addr_t *out_base_address);
 extern kern_status_t address_space_unmap(
@@ -67,7 +68,7 @@ extern kern_status_t address_space_release(
 extern kern_status_t vm_controller_create(kern_handle_t *out);
 extern kern_status_t vm_controller_recv(
 	kern_handle_t ctrl,
-	equeue_packet_page_request_t *out);
+	equeue_packet_vm_request_t *out);
 extern kern_status_t vm_controller_recv_async(
 	kern_handle_t ctrl,
 	kern_handle_t eq,
@@ -80,6 +81,14 @@ extern kern_status_t vm_controller_create_object(
 	size_t data_len,
 	vm_prot_t prot,
 	kern_handle_t *out);
+extern kern_status_t vm_controller_prepare_attach(
+	kern_handle_t ctrl,
+	uint64_t req_id,
+	kern_handle_t *out_vmo);
+extern kern_status_t vm_controller_finish_attach(
+	kern_handle_t ctrl,
+	uint64_t req_id,
+	equeue_key_t new_key);
 extern kern_status_t vm_controller_detach_object(
 	kern_handle_t ctrl,
 	kern_handle_t vmo);

libmagenta/include/magenta/signal.h

@@ -1,5 +1,5 @@
-#ifndef MANGO_SIGNAL_H_
-#define MANGO_SIGNAL_H_
+#ifndef MAGENTA_SIGNAL_H_
+#define MAGENTA_SIGNAL_H_
 
 #define THREAD_SIGNAL_STOPPED                 0x01u
 

libmagenta/include/magenta/status.h

@@ -1,5 +1,5 @@
-#ifndef MANGO_STATUS_H_
-#define MANGO_STATUS_H_
+#ifndef MAGENTA_STATUS_H_
+#define MAGENTA_STATUS_H_
 
 #define KERN_OK               (0)
 #define KERN_UNIMPLEMENTED    (1)

libmagenta/include/magenta/syscall.h

@@ -0,0 +1,58 @@
+#ifndef MAGENTA_SYSCALL_H_
+#define MAGENTA_SYSCALL_H_
+
+#define SYS_KERN_LOG                     1
+#define SYS_KERN_HANDLE_CLOSE            2
+#define SYS_KERN_HANDLE_TRANSFER         3
+#define SYS_KERN_HANDLE_CONTROL          4
+#define SYS_KERN_CONFIG_GET              5
+#define SYS_KERN_CONFIG_SET              6
+#define SYS_KERN_OBJECT_WAIT             7
+#define SYS_KERN_OBJECT_WAIT_ASYNC       8
+#define SYS_TASK_EXIT                    9
+#define SYS_TASK_SELF                    10
+#define SYS_TASK_CREATE                  11
+#define SYS_TASK_CREATE_THREAD           12
+#define SYS_TASK_GET_ADDRESS_SPACE       13
+#define SYS_TASK_CONFIG_GET              14
+#define SYS_TASK_CONFIG_SET              15
+#define SYS_TASK_DUPLICATE               16
+#define SYS_THREAD_SELF                  17
+#define SYS_THREAD_START                 18
+#define SYS_THREAD_EXIT                  19
+#define SYS_THREAD_CONFIG_GET            20
+#define SYS_THREAD_CONFIG_SET            21
+#define SYS_VM_OBJECT_CREATE             22
+#define SYS_VM_OBJECT_READ               23
+#define SYS_VM_OBJECT_WRITE              24
+#define SYS_VM_OBJECT_COPY               25
+#define SYS_ADDRESS_SPACE_READ           26
+#define SYS_ADDRESS_SPACE_WRITE          27
+#define SYS_ADDRESS_SPACE_MAP            28
+#define SYS_ADDRESS_SPACE_UNMAP          29
+#define SYS_ADDRESS_SPACE_RESERVE        30
+#define SYS_ADDRESS_SPACE_RELEASE        31
+#define SYS_MSG_SEND                     32
+#define SYS_MSG_RECV                     33
+#define SYS_MSG_REPLY                    34
+#define SYS_MSG_READ                     35
+#define SYS_MSG_WRITE                    36
+#define SYS_CHANNEL_CREATE               37
+#define SYS_PORT_CREATE                  38
+#define SYS_PORT_CONNECT                 39
+#define SYS_PORT_DISCONNECT              40
+#define SYS_EQUEUE_CREATE                41
+#define SYS_EQUEUE_DEQUEUE               42
+#define SYS_VM_CONTROLLER_CREATE         43
+#define SYS_VM_CONTROLLER_RECV           44
+#define SYS_VM_CONTROLLER_RECV_ASYNC     45
+#define SYS_VM_CONTROLLER_CREATE_OBJECT  46
+#define SYS_VM_CONTROLLER_PREPARE_ATTACH 47
+#define SYS_VM_CONTROLLER_FINISH_ATTACH  48
+#define SYS_VM_CONTROLLER_DETACH_OBJECT  49
+#define SYS_VM_CONTROLLER_SUPPLY_PAGES   50
+#define SYS_FUTEX_WAIT                   51
+#define SYS_FUTEX_WAKE                   52
+#define SYS_KERN_OBJECT_QUERY            53
+
+#endif

libmagenta/include/magenta/types.h

@@ -1,5 +1,5 @@
-#ifndef MANGO_TYPES_H_
-#define MANGO_TYPES_H_
+#ifndef MAGENTA_TYPES_H_
+#define MAGENTA_TYPES_H_
 
 #include <stddef.h>
 #include <stdint.h>
@@ -16,12 +16,17 @@
 #define MAP_ADDRESS_INVALID          ((virt_addr_t)0)
 #define KERN_HANDLE_INVALID          ((kern_handle_t)0xFFFFFFFF)
 
+/* task creation flags */
+#define TASK_F_DEFAULT               0x0000u
+#define TASK_F_CLONE_ALL_HANDLES     0x0001u
+
 /* config keys for use with kern_config_get/kern_config_set */
 #define KERN_CFG_INVALID             0x00000u
 #define KERN_CFG_PAGE_SIZE           0x00001u
 
 /* config keys for use with task_config_get/task_config_set */
 #define TASK_CFG_INVALID             0x00000u
+#define TASK_CFG_ID                  0x10001u
 
 /* config keys for use with thread_config_get/thread_config_set */
 #define THREAD_CFG_INVALID           0x00000u
@@ -34,6 +39,16 @@
 #define KERN_HANDLE_FLAG2            0x40000000UL
 #define KERN_HANDLE_FLAG3            0x80000000UL
 
+/* flags to specify when creating address-space mappings */
+/* this mapping is private. if a task with this mapping is duplicated,
+   the duplicate task will receive a copy-on-write mapping. changes to one
+   mapping will not be visible to the other. */
+#define VM_PRIVATE                   0x0000u
+/* this mapping is shared. if a task with this mapping is duplicated,
+ * the duplicate will receive a mapping of the same data. changes to one mapping
+ * will be visibile to the other */
+#define VM_SHARED                    0x0001u
+
 /* maximum number of handles that can be sent in a single message */
 #define KERN_MSG_MAX_HANDLES         64
 
@@ -61,13 +76,14 @@
 #define KERN_MSG_EVENT_DISCONNECTION 2
 
 /* equeue packet types */
-#define EQUEUE_PKT_PAGE_REQUEST      0x01u
+#define EQUEUE_PKT_VM_REQUEST        0x01u
 #define EQUEUE_PKT_ASYNC_SIGNAL      0x02u
 
-/* page request types */
-#define PAGE_REQUEST_READ            0x01u
-#define PAGE_REQUEST_DIRTY           0x02u
-#define PAGE_REQUEST_DETACH          0x03u
+/* vm request types */
+#define VM_REQUEST_READ              0x01u
+#define VM_REQUEST_DIRTY             0x02u
+#define VM_REQUEST_ATTACH            0x03u
+#define VM_REQUEST_DETACH            0x04u
 
 /* futex special values */
 #define FUTEX_WAKE_ALL               ((size_t)-1)
@@ -106,6 +122,8 @@ typedef unsigned int kern_status_t;
 typedef uint32_t kern_handle_t;
 typedef uint32_t kern_config_key_t;
 typedef uint32_t vm_prot_t;
+typedef uint32_t vm_flags_t;
+typedef uint32_t task_flags_t;
 typedef int64_t ssize_t;
 typedef uint32_t kern_futex_t;
 typedef uint32_t kern_msg_type_t;
@@ -175,14 +193,33 @@ typedef struct {
 	/* the key of the vm-object for which the page request relates, as
 	 * specified when the vm-object was created */
 	equeue_key_t req_vmo;
-	/* page request type. one of PAGE_REQUEST_* */
+	/* page request type. one of VM_REQUEST_* */
 	unsigned short req_type;
-	/* of the offset into the vm-object for which pages are being requested
-	 */
-	off_t req_offset;
-	/* the length in bytes of the region being requested */
-	size_t req_length;
-} equeue_packet_page_request_t;
+	/* the offset into the vm-object for which pages are being requested */
+	union {
+		/* used for:
+		 * 	VM_REQUEST_READ
+		 * 	VM_REQUEST_DIRTY
+		 */
+		struct {
+			off_t req_offset;
+			/* the length in bytes of the region being requested */
+			size_t req_length;
+		};
+
+		/* used for:
+		 * 	VM_REQUEST_ATTACH
+		 */
+		struct {
+			/* the key of the original/source vmo. */
+			equeue_key_t req_src_vmo;
+			/* a request ID. used to retrieve information about
+			 * the newly-attached object, as the server won't know
+			 * about it yet, and won't have a handle to it. */
+			uint64_t req_id;
+		};
+	};
+} equeue_packet_vm_request_t;
 
 typedef struct {
 	/* the type of packet. one of EQUEUE_PKT_* */
@@ -192,8 +229,8 @@ typedef struct {
 	equeue_key_t p_key;
 
 	union {
-		/* p_type = EQUEUE_PKT_PAGE_REQUEST */
-		equeue_packet_page_request_t page_request;
+		/* p_type = EQUEUE_PKT_VM_REQUEST */
+		equeue_packet_vm_request_t vm_request;
 		/* p_type = EQUEUE_PKT_ASYNC_SIGNAL */
 		equeue_packet_async_signal_t async_signal;
 	};

libmango/include/mango/syscall.h

@@ -1,56 +0,0 @@
-#ifndef MANGO_SYSCALL_H_
-#define MANGO_SYSCALL_H_
-
-#define SYS_KERN_LOG                    1
-#define SYS_KERN_HANDLE_CLOSE           2
-#define SYS_KERN_HANDLE_TRANSFER        3
-#define SYS_KERN_CONFIG_GET             4
-#define SYS_KERN_CONFIG_SET             5
-#define SYS_KERN_OBJECT_WAIT            6
-#define SYS_KERN_OBJECT_WAIT_ASYNC      7
-#define SYS_TASK_EXIT                   8
-#define SYS_TASK_SELF                   9
-#define SYS_TASK_CREATE                 10
-#define SYS_TASK_CREATE_THREAD          11
-#define SYS_TASK_GET_ADDRESS_SPACE      12
-#define SYS_TASK_CONFIG_GET             13
-#define SYS_TASK_CONFIG_SET             14
-#define SYS_THREAD_SELF                 15
-#define SYS_THREAD_START                16
-#define SYS_THREAD_EXIT                 17
-#define SYS_THREAD_CONFIG_GET           18
-#define SYS_THREAD_CONFIG_SET           19
-#define SYS_VM_OBJECT_CREATE            20
-#define SYS_VM_OBJECT_READ              21
-#define SYS_VM_OBJECT_WRITE             22
-#define SYS_VM_OBJECT_COPY              23
-#define SYS_ADDRESS_SPACE_READ          24
-#define SYS_ADDRESS_SPACE_WRITE         25
-#define SYS_ADDRESS_SPACE_MAP           26
-#define SYS_ADDRESS_SPACE_UNMAP         27
-#define SYS_ADDRESS_SPACE_RESERVE       28
-#define SYS_ADDRESS_SPACE_RELEASE       29
-#define SYS_MSG_SEND                    30
-#define SYS_MSG_RECV                    31
-#define SYS_MSG_REPLY                   32
-#define SYS_MSG_READ                    33
-#define SYS_MSG_WRITE                   34
-#define SYS_CHANNEL_CREATE              35
-#define SYS_PORT_CREATE                 36
-#define SYS_PORT_CONNECT                37
-#define SYS_PORT_DISCONNECT             38
-#define SYS_EQUEUE_CREATE               39
-#define SYS_EQUEUE_DEQUEUE              40
-#define SYS_VM_CONTROLLER_CREATE        41
-#define SYS_VM_CONTROLLER_RECV          42
-#define SYS_VM_CONTROLLER_RECV_ASYNC    43
-#define SYS_VM_CONTROLLER_CREATE_OBJECT 44
-#define SYS_VM_CONTROLLER_DETACH_OBJECT 45
-#define SYS_VM_CONTROLLER_SUPPLY_PAGES  46
-#define SYS_FUTEX_WAIT                  47
-#define SYS_FUTEX_WAKE                  48
-#define SYS_KERN_OBJECT_QUERY           49
-#define SYS_TASK_DUPLICATE              50
-#define SYS_KERN_HANDLE_CONTROL         51
-
-#endif

sched/task.c

@@ -171,8 +171,13 @@ struct task *task_alloc(void)
 	return t;
 }
 
-struct task *task_create(const char *name, size_t name_len)
+struct task *task_create(
+	struct task *parent,
+	task_flags_t task_flags,
+	const char *name,
+	size_t name_len)
 {
+	kern_status_t status = KERN_OK;
 	struct task *task = task_alloc();
 	if (!task) {
 		return NULL;
@@ -191,9 +196,21 @@ struct task *task_create(const char *name, size_t name_len)
 		VM_USER_LIMIT,
 		&task->t_address_space);
 
+	if (task_flags & TASK_F_CLONE_ALL_HANDLES) {
+		status = handle_table_duplicate(
+			parent->t_handles,
+			&task->t_handles);
+	} else {
+		task->t_handles = handle_table_create();
+	}
+
+	if (status != KERN_OK) {
+		object_unref(&task->t_base);
+		return NULL;
+	}
+
 	task->t_address_space->s_pmap = pmap;
 	task->t_state = TASK_RUNNING;
-	task->t_handles = handle_table_create();
 
 	if (name) {
 		name_len = MIN(name_len, sizeof task->t_name - 1);
@@ -280,6 +297,40 @@ struct task *task_from_tid(tid_t id)
 	return t;
 }
 
+kern_status_t task_config_get(
+	struct task *task,
+	kern_config_key_t key,
+	void *out,
+	size_t max)
+{
+	switch (key) {
+	case TASK_CFG_ID: {
+		if (max != sizeof(tid_t)) {
+			return KERN_INVALID_ARGUMENT;
+		}
+
+		tid_t *value = out;
+		*value = task->t_id;
+		return KERN_OK;
+	}
+
+	default:
+		return KERN_INVALID_ARGUMENT;
+	}
+}
+
+kern_status_t task_config_set(
+	struct task *task,
+	kern_config_key_t key,
+	const void *ptr,
+	size_t len)
+{
+	switch (key) {
+	default:
+		return KERN_INVALID_ARGUMENT;
+	}
+}
+
 void task_exit(int status)
 {
 	struct task *self = get_current_task();
@@ -325,6 +376,7 @@ void task_exit(int status)
 	spin_lock(&self->t_handles_lock);
 
 	pmap_switch(get_kernel_pmap());
+	self->t_address_space->s_pmap = PMAP_INVALID;
 	pmap_destroy(self->t_pmap);
 
 	task_unlock(self);

sched/thread.c

@@ -5,7 +5,7 @@
 #include <kernel/printk.h>
 #include <kernel/task.h>
 #include <kernel/thread.h>
-#include <mango/signal.h>
+#include <magenta/signal.h>
 
 #define THREAD_CAST(p) OBJECT_C_CAST(struct thread, tr_base, &thread_type, p)
 
@@ -131,7 +131,12 @@ kern_status_t thread_init_user_clone(
 
 	/* this context will be used by ml_user_return to jump to userspace
 	 * with the specified instruction pointer and user stack */
-	ml_thread_clone_user_context(src->tr_irqctx, return_value, &thr->tr_sp);
+	ml_thread_clone_user_context(
+		src->tr_irqctx,
+		&src->tr_ml,
+		&thr->tr_ml,
+		return_value,
+		&thr->tr_sp);
 	/* this context will be used by the scheduler and ml_thread_switch to
 	 * jump to ml_user_return in kernel mode with the thread's kernel stack.
 	 */

syscall/address-space.c

@@ -125,6 +125,7 @@ kern_status_t sys_address_space_map(
 	kern_handle_t object_handle,
 	off_t object_offset,
 	size_t length,
+	vm_flags_t flags,
 	vm_prot_t prot,
 	virt_addr_t *out_base_address)
 {
@@ -140,8 +141,8 @@ kern_status_t sys_address_space_map(
 	}
 
 	kern_status_t status = KERN_OK;
-	unsigned long flags;
-	task_lock_irqsave(self, &flags);
+	unsigned long irq_flags;
+	task_lock_irqsave(self, &irq_flags);
 
 	struct object *region_obj = NULL, *vmo_obj = NULL;
 	handle_flags_t region_flags = 0, vmo_flags = 0;
@@ -151,34 +152,34 @@ kern_status_t sys_address_space_map(
 		&region_obj,
 		&region_flags);
 	if (status != KERN_OK) {
-		task_unlock_irqrestore(self, flags);
+		task_unlock_irqrestore(self, irq_flags);
 		put_current_task(self);
 		return status;
 	}
 
 	status = task_resolve_handle(self, object_handle, &vmo_obj, &vmo_flags);
 	if (status != KERN_OK) {
-		task_unlock_irqrestore(self, flags);
+		task_unlock_irqrestore(self, irq_flags);
 		put_current_task(self);
 		return status;
 	}
 
 	struct address_space *region = address_space_cast(region_obj);
 	if (!region) {
-		task_unlock_irqrestore(self, flags);
+		task_unlock_irqrestore(self, irq_flags);
 		put_current_task(self);
 		return KERN_INVALID_ARGUMENT;
 	}
 
 	struct vm_object *vmo = vm_object_cast(vmo_obj);
 	if (!vmo) {
-		task_unlock_irqrestore(self, flags);
+		task_unlock_irqrestore(self, irq_flags);
 		put_current_task(self);
 		return KERN_INVALID_ARGUMENT;
 	}
 
-	task_unlock_irqrestore(self, flags);
-	address_space_lock_irqsave(region, &flags);
+	task_unlock_irqrestore(self, irq_flags);
+	address_space_lock_irqsave(region, &irq_flags);
 	/* address_space_map will take care of locking `vmo` */
 	status = address_space_map(
 		region,
@@ -186,9 +187,10 @@ kern_status_t sys_address_space_map(
 		vmo,
 		object_offset,
 		length,
+		flags,
 		prot,
 		out_base_address);
-	address_space_unlock_irqrestore(region, flags);
+	address_space_unlock_irqrestore(region, irq_flags);
 
 	object_unref(vmo_obj);
 	object_unref(region_obj);

syscall/dispatch.c

@@ -11,6 +11,8 @@ static const virt_addr_t syscall_table[] = {
 	SYSCALL_TABLE_ENTRY(TASK_CREATE_THREAD, task_create_thread),
 	SYSCALL_TABLE_ENTRY(TASK_GET_ADDRESS_SPACE, task_get_address_space),
 	SYSCALL_TABLE_ENTRY(TASK_DUPLICATE, task_duplicate),
+	SYSCALL_TABLE_ENTRY(TASK_CONFIG_GET, task_config_get),
+	SYSCALL_TABLE_ENTRY(TASK_CONFIG_SET, task_config_set),
 	SYSCALL_TABLE_ENTRY(THREAD_SELF, thread_self),
 	SYSCALL_TABLE_ENTRY(THREAD_START, thread_start),
 	SYSCALL_TABLE_ENTRY(THREAD_EXIT, thread_exit),
@@ -47,6 +49,12 @@ static const virt_addr_t syscall_table[] = {
 	SYSCALL_TABLE_ENTRY(
 		VM_CONTROLLER_CREATE_OBJECT,
 		vm_controller_create_object),
+	SYSCALL_TABLE_ENTRY(
+		VM_CONTROLLER_PREPARE_ATTACH,
+		vm_controller_prepare_attach),
+	SYSCALL_TABLE_ENTRY(
+		VM_CONTROLLER_FINISH_ATTACH,
+		vm_controller_finish_attach),
 	SYSCALL_TABLE_ENTRY(
 		VM_CONTROLLER_DETACH_OBJECT,
 		vm_controller_detach_object),

syscall/handle.c

@@ -61,6 +61,7 @@ kern_status_t sys_kern_handle_transfer(
 		src_task = task_cast(obj);
 		if (!src_task) {
 			status = KERN_INVALID_ARGUMENT;
+			task_unlock_irqrestore(self, flags);
 			goto cleanup;
 		}
 	} else {
@@ -81,6 +82,7 @@ kern_status_t sys_kern_handle_transfer(
 		dest_task = task_cast(obj);
 		if (!dest_task) {
 			status = KERN_INVALID_ARGUMENT;
+			task_unlock_irqrestore(self, flags);
 			goto cleanup;
 		}
 	} else {
@@ -92,12 +94,12 @@ kern_status_t sys_kern_handle_transfer(
 		src_handle,
 		&src_object,
 		&handle_flags);
+	task_unlock_irqrestore(self, flags);
+
 	if (status != KERN_OK) {
 		goto cleanup;
 	}
 
-	task_unlock_irqrestore(self, flags);
-
 	struct handle *dest = NULL;
 	task_lock_irqsave(dest_task, &flags);
 	status = handle_table_alloc_handle(

syscall/object.c

@@ -4,8 +4,8 @@
 #include <kernel/task.h>
 #include <kernel/thread.h>
 #include <kernel/wait.h>
-#include <mango/status.h>
-#include <mango/types.h>
+#include <magenta/status.h>
+#include <magenta/types.h>
 
 kern_status_t sys_kern_object_wait(kern_wait_item_t *items, size_t nr_items)
 {

syscall/task.c

@@ -53,6 +53,7 @@ kern_status_t sys_task_self(kern_handle_t *out)
 
 kern_status_t sys_task_create(
 	kern_handle_t parent_handle,
+	task_flags_t task_flags,
 	const char *name,
 	size_t name_len,
 	kern_handle_t *out_task,
@@ -124,7 +125,7 @@ kern_status_t sys_task_create(
 
 	task_unlock_irqrestore(self, flags);
 
-	struct task *child = task_create(name, name_len);
+	struct task *child = task_create(parent, task_flags, name, name_len);
 	if (!child) {
 		object_unref(parent_obj);
 
@@ -291,6 +292,89 @@ kern_status_t sys_task_get_address_space(
 	return KERN_OK;
 }
 
+kern_status_t sys_task_config_get(
+	kern_handle_t task_handle,
+	kern_config_key_t key,
+	void *ptr,
+	size_t len)
+{
+	unsigned long flags;
+	struct task *self = get_current_task();
+
+	if (!validate_access_w(self, ptr, len)) {
+		put_current_task(self);
+		return KERN_MEMORY_FAULT;
+	}
+
+	struct object *task_obj;
+	handle_flags_t task_flags;
+	task_lock_irqsave(self, &flags);
+	kern_status_t status = task_resolve_handle(
+		self,
+		task_handle,
+		&task_obj,
+		&task_flags);
+	put_current_task(self);
+	task_unlock_irqrestore(self, flags);
+
+	if (status != KERN_OK) {
+		return status;
+	}
+
+	struct task *task = task_cast(task_obj);
+	task_unlock_irqrestore(self, flags);
+
+	if (task) {
+		status = task_config_get(task, key, ptr, len);
+	} else {
+		status = KERN_INVALID_ARGUMENT;
+	}
+
+	object_unref(task_obj);
+
+	return status;
+}
+
+kern_status_t sys_task_config_set(
+	kern_handle_t task_handle,
+	kern_config_key_t key,
+	const void *ptr,
+	size_t len)
+{
+	unsigned long flags;
+	struct task *self = get_current_task();
+
+	if (!validate_access_w(self, ptr, len)) {
+		put_current_task(self);
+		return KERN_MEMORY_FAULT;
+	}
+
+	struct object *task_obj;
+	handle_flags_t task_flags;
+	task_lock_irqsave(self, &flags);
+	kern_status_t status = task_resolve_handle(
+		self,
+		task_handle,
+		&task_obj,
+		&task_flags);
+	task_unlock_irqrestore(self, flags);
+	put_current_task(self);
+	if (status != KERN_OK) {
+		return status;
+	}
+
+	struct task *task = task_cast(task_obj);
+	if (task) {
+		status = task_config_set(task, key, ptr, len);
+	} else {
+		status = KERN_INVALID_ARGUMENT;
+	}
+
+	object_unref(task_obj);
+
+	return status;
+}
+
 kern_status_t sys_thread_self(kern_handle_t *out)
 {
 	struct task *self = get_current_task();
@@ -493,7 +577,11 @@ kern_status_t sys_task_duplicate(
 		return status;
 	}
 
-	struct task *new_task = task_create(self->t_name, strlen(self->t_name));
+	struct task *new_task = task_create(
+		self,
+		TASK_F_CLONE_ALL_HANDLES,
+		self->t_name,
+		strlen(self->t_name));
 	if (!new_task) {
 		put_current_task(self);
 		return KERN_NO_MEMORY;
@@ -526,18 +614,19 @@ kern_status_t sys_task_duplicate(
 		return status;
 	}
 
-	schedule_thread_on_cpu(new_thread);
-
 	child_handle_slot->h_object = &new_task->t_base;
-	space_handle_slot->h_object = &new_task->t_address_space->s_base;
+	space_handle_slot->h_object
+		= object_ref(&new_task->t_address_space->s_base);
 	task_unlock_irqrestore(self, flags);
 
+	/* clear TLB */
+	pmap_flush();
+	put_current_task(self);
+
 	*out_task = child_handle;
 	*out_address_space = space_handle;
 
-	/* clear TLB */
-	pmap_switch(self->t_pmap);
-	put_current_task(self);
+	schedule_thread_on_cpu(new_thread);
 
 	return KERN_OK;
 }

syscall/vm-controller.c

@@ -32,7 +32,7 @@ kern_status_t sys_vm_controller_create(kern_handle_t *out)
 
 kern_status_t sys_vm_controller_recv(
 	kern_handle_t ctrl_handle,
-	equeue_packet_page_request_t *out)
+	equeue_packet_vm_request_t *out)
 {
 	struct task *self = get_current_task();
 
@@ -148,8 +148,8 @@ kern_status_t sys_vm_controller_create_object(
 	}
 
 	kern_status_t status = KERN_OK;
-	unsigned long flags;
-	task_lock_irqsave(self, &flags);
+	unsigned long irq_flags;
+	task_lock_irqsave(self, &irq_flags);
 
 	struct object *ctrl_obj = NULL;
 	handle_flags_t handle_flags = 0;
@@ -159,7 +159,7 @@ kern_status_t sys_vm_controller_create_object(
 		&ctrl_obj,
 		&handle_flags);
 	if (status != KERN_OK) {
-		task_unlock_irqrestore(self, flags);
+		task_unlock_irqrestore(self, irq_flags);
 		put_current_task(self);
 		return status;
 	}
@@ -173,14 +173,14 @@ kern_status_t sys_vm_controller_create_object(
 		&out_handle);
 
 	struct vm_controller *ctrl = vm_controller_cast(ctrl_obj);
-	task_unlock_irqrestore(self, flags);
+	task_unlock_irqrestore(self, irq_flags);
 	if (!ctrl) {
 		object_unref(ctrl_obj);
 		put_current_task(self);
 		return KERN_INVALID_ARGUMENT;
 	}
 
-	vm_controller_lock_irqsave(ctrl, &flags);
+	vm_controller_lock_irqsave(ctrl, &irq_flags);
 	struct vm_object *out_vmo = NULL;
 	status = vm_controller_create_object(
 		ctrl,
@@ -190,14 +190,14 @@ kern_status_t sys_vm_controller_create_object(
 		data_len,
 		prot,
 		&out_vmo);
-	vm_controller_unlock_irqrestore(ctrl, flags);
+	vm_controller_unlock_irqrestore(ctrl, irq_flags);
 
 	object_unref(ctrl_obj);
 
 	if (status != KERN_OK) {
-		task_lock_irqsave(self, &flags);
+		task_lock_irqsave(self, &irq_flags);
 		handle_table_free_handle(self->t_handles, out_handle);
-		task_unlock_irqrestore(self, flags);
+		task_unlock_irqrestore(self, irq_flags);
 		put_current_task(self);
 		return status;
 	}
@@ -209,6 +209,116 @@ kern_status_t sys_vm_controller_create_object(
 	return KERN_OK;
 }
 
+kern_status_t sys_vm_controller_prepare_attach(
+	kern_handle_t ctrl_handle,
+	uint64_t req_id,
+	kern_handle_t *out_vmo)
+{
+	struct task *self = get_current_task();
+	if (!out_vmo || !validate_access_w(self, out_vmo, sizeof *out_vmo)) {
+		return KERN_MEMORY_FAULT;
+	}
+
+	kern_status_t status = KERN_OK;
+	unsigned long flags;
+	task_lock_irqsave(self, &flags);
+
+	struct object *ctrl_obj = NULL;
+	handle_flags_t ctrl_flags = 0;
+	status = task_resolve_handle(self, ctrl_handle, &ctrl_obj, &ctrl_flags);
+	if (status != KERN_OK) {
+		task_unlock_irqrestore(self, flags);
+		put_current_task(self);
+		return status;
+	}
+
+	struct handle *out_slot = NULL;
+	kern_handle_t out_handle = KERN_HANDLE_INVALID;
+	status = handle_table_alloc_handle(
+		self->t_handles,
+		KERN_HANDLE_INVALID,
+		&out_slot,
+		&out_handle);
+	if (status != KERN_OK) {
+		object_unref(ctrl_obj);
+		task_unlock_irqrestore(self, flags);
+		put_current_task(self);
+		return status;
+	}
+
+	struct vm_controller *ctrl = vm_controller_cast(ctrl_obj);
+	task_unlock_irqrestore(self, flags);
+
+	if (!ctrl) {
+		object_unref(ctrl_obj);
+		return KERN_INVALID_ARGUMENT;
+	}
+
+	vm_controller_lock_irqsave(ctrl, &flags);
+
+	struct vm_object *vmo = NULL;
+	status = vm_controller_prepare_attach(ctrl, req_id, &vmo);
+	vm_controller_unlock_irqrestore(ctrl, flags);
+
+	object_unref(ctrl_obj);
+	if (status != KERN_OK) {
+		task_lock_irqsave(self, &flags);
+		handle_table_free_handle(self->t_handles, out_handle);
+		task_unlock_irqrestore(self, flags);
+
+		return status;
+	}
+
+	out_slot->h_object = &vmo->vo_base;
+	put_current_task(self);
+
+	*out_vmo = out_handle;
+
+	return KERN_OK;
+}
+
+kern_status_t sys_vm_controller_finish_attach(
+	kern_handle_t ctrl_handle,
+	uint64_t req_id,
+	equeue_key_t new_key)
+{
+	struct task *self = get_current_task();
+
+	kern_status_t status = KERN_OK;
+	unsigned long flags;
+	task_lock_irqsave(self, &flags);
+
+	struct object *ctrl_obj = NULL;
+	handle_flags_t ctrl_flags = 0;
+	status = task_resolve_handle(self, ctrl_handle, &ctrl_obj, &ctrl_flags);
+	if (status != KERN_OK) {
+		task_unlock_irqrestore(self, flags);
+		put_current_task(self);
+		return status;
+	}
+
+	struct vm_controller *ctrl = vm_controller_cast(ctrl_obj);
+	task_unlock_irqrestore(self, flags);
+	put_current_task(self);
+
+	if (!ctrl) {
+		object_unref(ctrl_obj);
+		return KERN_INVALID_ARGUMENT;
+	}
+
+	vm_controller_lock_irqsave(ctrl, &flags);
+
+	status = vm_controller_finish_attach(ctrl, req_id, new_key);
+	vm_controller_unlock_irqrestore(ctrl, flags);
+
+	object_unref(ctrl_obj);
+	if (status != KERN_OK) {
+		return status;
+	}
+
+	return KERN_OK;
+}
+
 kern_status_t sys_vm_controller_detach_object(
 	kern_handle_t ctrl_handle,
 	kern_handle_t vmo_handle)
@@ -315,6 +425,8 @@ kern_status_t sys_vm_controller_supply_pages(
 
 	vm_controller_lock_irqsave(ctrl, &flags);
 	vm_object_lock_pair(src, dst);
+	equeue_key_t requester_key = dst->vo_key;
+
 	status = vm_controller_supply_pages(
 		ctrl,
 		dst,
@@ -323,6 +435,12 @@ kern_status_t sys_vm_controller_supply_pages(
 		src_offset,
 		count);
 	vm_object_unlock_pair(src, dst);
+	vm_controller_fulfill_requests(
+		ctrl,
+		requester_key,
+		dst_offset,
+		count,
+		status);
 	vm_controller_unlock_irqrestore(ctrl, flags);
 
 	object_unref(ctrl_obj);
@@ -330,5 +448,8 @@ kern_status_t sys_vm_controller_supply_pages(
 	object_unref(src_obj);
 	put_current_task(self);
 
+	/* TODO flush individual pages in vm_object_transfer */
+	pmap_flush();
+
 	return status;
 }

syscall/vm-object.c

@@ -58,20 +58,31 @@ kern_status_t sys_vm_object_read(
 
 	struct object *obj = NULL;
 	handle_flags_t flags = 0;
+	unsigned long irq_flags = 0;
+	task_lock_irqsave(self, &irq_flags);
 	kern_status_t status = task_resolve_handle(self, object, &obj, &flags);
+	task_unlock_irqrestore(self, irq_flags);
+	put_current_task(self);
+
 	if (status != KERN_OK) {
-		put_current_task(self);
 		return status;
 	}
 
 	struct vm_object *vmo = vm_object_cast(obj);
 	if (!vmo) {
-		put_current_task(self);
+		object_unref(obj);
 		return KERN_INVALID_ARGUMENT;
 	}
 
-	status = vm_object_read(vmo, dst, offset, count, nr_read);
-	put_current_task(self);
+	vm_object_lock_irqsave(vmo, &irq_flags);
+	status = vm_object_prefetch(vmo, offset, count, &irq_flags);
+	if (status == KERN_OK) {
+		status = vm_object_read(vmo, dst, offset, count, nr_read);
+	}
+
+	vm_object_unlock_irqrestore(vmo, irq_flags);
+	object_unref(obj);
+
 	return status;
 }
 
@@ -97,20 +108,25 @@ kern_status_t sys_vm_object_write(
 
 	struct object *obj = NULL;
 	handle_flags_t flags = 0;
+	unsigned long irq_flags = 0;
+	task_lock_irqsave(self, &irq_flags);
 	kern_status_t status = task_resolve_handle(self, object, &obj, &flags);
+	task_unlock_irqrestore(self, irq_flags);
+	put_current_task(self);
+
 	if (status != KERN_OK) {
-		put_current_task(self);
 		return status;
 	}
 
 	struct vm_object *vmo = vm_object_cast(obj);
 	if (!vmo) {
-		put_current_task(self);
 		return KERN_INVALID_ARGUMENT;
 	}
 
+	vm_object_lock_irqsave(vmo, &irq_flags);
 	status = vm_object_write(vmo, src, offset, count, nr_written);
-	put_current_task(self);
+	vm_object_unlock_irqrestore(vmo, irq_flags);
+
 	return status;
 }
 
@@ -162,13 +178,28 @@ kern_status_t sys_vm_object_copy(
 	put_current_task(self);
 
 	struct vm_object *dst_vmo = vm_object_cast(dst_obj);
+	if (!dst_vmo) {
+		return KERN_INVALID_ARGUMENT;
+	}
+
 	struct vm_object *src_vmo = vm_object_cast(src_obj);
-	if (!dst_vmo || !src_vmo) {
-		object_unref(src_obj);
+	if (!src_vmo) {
 		object_unref(dst_obj);
 		return KERN_INVALID_ARGUMENT;
 	}
 
+	unsigned long irq_flags = 0;
+	vm_object_lock_irqsave(src_vmo, &irq_flags);
+	status = vm_object_prefetch(src_vmo, src_offset, count, &irq_flags);
+	vm_object_unlock_irqrestore(src_vmo, irq_flags);
+
+	if (status != KERN_OK) {
+		object_unref(src_obj);
+		object_unref(dst_obj);
+		return status;
+	}
+
+	vm_object_lock_pair_irqsave(src_vmo, dst_vmo, &irq_flags);
 	status = vm_object_copy(
 		dst_vmo,
 		dst_offset,
@@ -176,6 +207,7 @@ kern_status_t sys_vm_object_copy(
 		src_offset,
 		count,
 		nr_copied);
+	vm_object_unlock_pair_irqrestore(src_vmo, dst_vmo, irq_flags);
 
 	object_unref(src_obj);
 	object_unref(dst_obj);

tools/CMakeLists.txt

@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.13)
-project(mango-tools C)
+project(magenta-tools C)
 
 set(tool_dirs e64patch)
 

tools/bochsrc.bxrc

@@ -10,7 +10,7 @@ floppy_bootsig_check: disabled=0
 floppya: type=1_44
 # no floppyb
 ata0: enabled=true, ioaddr1=0x1f0, ioaddr2=0x3f0, irq=14
-ata0-master: type=cdrom, path="build/mango-kernel.iso", status=inserted, model="Generic 1234", biosdetect=auto
+ata0-master: type=cdrom, path="build/magenta-kernel.iso", status=inserted, model="Generic 1234", biosdetect=auto
 ata0-slave: type=none
 ata1: enabled=true, ioaddr1=0x170, ioaddr2=0x370, irq=15
 ata1-master: type=none

tools/boot-image/grub.cfg

@@ -1,4 +1,4 @@
-menuentry "Mango Kernel" {
-	multiboot /boot/mango_kernel
+menuentry "Magenta Kernel" {
+	multiboot /boot/magenta_kernel
 	boot
 }

tools/kernel-debug/debug_session.sh

@@ -5,9 +5,9 @@ lldb_cfg=$2
 shift 2
 
 if command -v gdb &> /dev/null; then
-	printf "    \033[93;1mGDB\033[0m    boot/mango_kernel\n"
+	printf "    \033[93;1mGDB\033[0m    boot/magenta_kernel\n"
 	tmux \
-		new-session -d -s mango-debug "sleep 0.3; gdb -tui -x $gdb_cfg" \; \
+		new-session -d -s magenta-debug "sleep 0.3; gdb -tui -x $gdb_cfg" \; \
 		split-window -h -l 80 \; \
 		split-window -v -l 25 "$@"\; \
 		select-pane -t 1 \; \
@@ -15,9 +15,9 @@ if command -v gdb &> /dev/null; then
 		select-pane -t 0
 
 elif command -v lldb &> /dev/null; then
-	printf "    \033[93;1mLLDB\033[0m   boot/mango_kernel\n"
+	printf "    \033[93;1mLLDB\033[0m   boot/magenta_kernel\n"
 	tmux \
-		new-session -d -s mango-debug "sleep 0.1; lldb --source $lldb_cfg" \; \
+		new-session -d -s magenta-debug "sleep 0.1; lldb --source $lldb_cfg" \; \
 		split-window -h -l 160 \; \
 		split-window -v -l 25 "$@"\; \
 		select-pane -t 1 \; \
@@ -28,6 +28,6 @@ else
 	exit -1
 fi
 
-tmux a -t mango-debug
-tmux kill-session -t mango-debug
+tmux a -t magenta-debug
+tmux kill-session -t magenta-debug
 

tools/kernel-debug/gdb_session_init

@@ -1,4 +1,4 @@
 set confirm off
-symbol-file mango_kernel.debug
+symbol-file magenta_kernel.debug
 target remote localhost:1234
 set confirm on

tools/kernel-debug/lldb_session_init

@@ -1,2 +1,2 @@
-file mango_kernel.debug
+file magenta_kernel.debug
 gdb-remote localhost:1234

tools/magenta.install-cd

@@ -116,7 +116,7 @@ def choice_options(num_devices):
     return '1-{}'.format(num_devices)
 
 
-if not os.path.isfile('build/mango-kernel.iso'):
+if not os.path.isfile('build/magenta-kernel.iso'):
     print('No system ISO image found.')
     print('Please run \'make cd\' to generate an ISO image')
     exit(-1)
@@ -157,7 +157,7 @@ disk_prewrite(devices[choice][0])
 dd_args = [
     'sudo',
     'dd',
-    'if=build/mango-kernel.iso',
+    'if=build/magenta-kernel.iso',
     'of={}'.format(devices[choice][0]),
     'bs=1{}'.format('m' if sys.platform == 'darwin' else 'M')
 ]

tools/magenta.mkrescue

@@ -7,22 +7,22 @@ import sys
 import os
 import shutil
 
-kernel_src_path = os.path.join('build', 'mango_kernel')
+kernel_src_path = os.path.join('build', 'magenta_kernel')
 grub_cfg_src_path = os.path.join('tools', 'boot-image', 'grub.cfg')
-iso_build_dir = os.path.join('build', 'mango-kernel.iso-build')
-iso_path = os.path.join('build', 'mango-kernel.iso')
+iso_build_dir = os.path.join('build', 'magenta-kernel.iso-build')
+iso_path = os.path.join('build', 'magenta-kernel.iso')
 
 
 def in_source_tree():
-    return os.path.isfile('tools/mango.sync')
+    return os.path.isfile('tools/magenta.sync')
 
 
 if not in_source_tree():
-    print('This script must be executed from the root of the Mango source tree')
+    print('This script must be executed from the root of the Magenta source tree')
     exit(-1)
 
 if not os.path.isdir('build'):
-    print('Please build the Mango kernel before using this tool')
+    print('Please build the Magenta kernel before using this tool')
     exit(-1)
 
 if os.path.isdir(iso_build_dir):
@@ -33,7 +33,7 @@ os.mkdir(iso_build_dir)
 os.mkdir(os.path.join(iso_build_dir, 'boot'))
 os.mkdir(os.path.join(iso_build_dir, 'boot', 'grub'))
 
-shutil.copyfile(kernel_src_path, os.path.join(iso_build_dir, 'boot', 'mango_kernel'))
+shutil.copyfile(kernel_src_path, os.path.join(iso_build_dir, 'boot', 'magenta_kernel'))
 shutil.copyfile(grub_cfg_src_path, os.path.join(iso_build_dir, 'boot', 'grub', 'grub.cfg'))
 
 subprocess.run(['grub-mkrescue', '-o', iso_path, iso_build_dir])

tools/magenta.sync

@@ -16,7 +16,7 @@ rsync_path = os.getenv('RSYNC_PATH', default = 'rsync')
 
 
 def in_source_tree():
-    return os.path.isfile('tools/mango.sync')
+    return os.path.isfile('tools/magenta.sync')
 
 
 def create_sample_config():
@@ -78,7 +78,7 @@ def print_available_targets(targets):
 
 
 if not in_source_tree():
-    print('This script must be executed from the root of the Mango source tree')
+    print('This script must be executed from the root of the Magenta source tree')
     exit(-1)
 
 config = read_config()

vm/address-space.c

@@ -6,10 +6,11 @@
 #include <kernel/printk.h>
 #include <kernel/sched.h>
 #include <kernel/task.h>
+#include <kernel/thread.h>
 #include <kernel/util.h>
 #include <kernel/vm-controller.h>
 #include <kernel/vm-object.h>
-#include <mango/status.h>
+#include <magenta/status.h>
 
 /*** STATIC DATA + MACROS *****************************************************/
 
@@ -660,9 +661,8 @@ static void area_unmap(struct vm_area *area)
 	pmap_t pmap = area->vma_space->s_pmap;
 	virt_addr_t base = area->vma_base;
 	virt_addr_t limit = area->vma_limit;
-	for (virt_addr_t i = base; i < limit; i += VM_PAGE_SIZE) {
-		pmap_remove(pmap, i);
-	}
+	pmap_remove_range(pmap, base, limit - base);
+	pmap_flush();
 }
 
 static kern_status_t address_space_cleanup(struct object *obj)
@@ -705,6 +705,7 @@ kern_status_t address_space_map(
 	struct vm_object *object,
 	off_t object_offset,
 	size_t length,
+	vm_flags_t flags,
 	vm_prot_t prot,
 	virt_addr_t *out)
 {
@@ -762,6 +763,7 @@ kern_status_t address_space_map(
 	area->vma_space = root;
 	area->vma_object = object;
 	area->vma_prot = prot;
+	area->vma_flags = flags;
 	area->vma_object_offset = object_offset;
 	area->vma_base = map_address;
 	area->vma_limit = map_address + length - 1;
@@ -841,11 +843,9 @@ static kern_status_t split_area(
 	}
 
 	put_entry(&root->s_mappings, right);
-	for (size_t i = unmap_base; i < unmap_limit; i += VM_PAGE_SIZE) {
-		tracek("pmap_remove %zx", i);
-		pmap_remove(root->s_pmap, i);
-	}
 
+	pmap_remove_range(root->s_pmap, unmap_base, unmap_limit - unmap_base);
+	pmap_flush();
 	return KERN_OK;
 }
 
@@ -880,10 +880,8 @@ static kern_status_t left_reduce_area(
 	}
 
 	tracek(" pmap_remove %zx-%zx (%zx bytes)", base, base + length, length);
-	for (size_t i = base; i < limit; i += VM_PAGE_SIZE) {
-		pmap_remove(root->s_pmap, i);
-	}
-
+	pmap_remove_range(root->s_pmap, base, length);
+	pmap_flush();
 	return KERN_OK;
 }
 
@@ -917,10 +915,8 @@ static kern_status_t right_reduce_area(
 	}
 
 	tracek(" pmap_remove %zx-%zx (%zx bytes)", base, base + length, length);
-	for (size_t i = base; i < limit; i += VM_PAGE_SIZE) {
-		pmap_remove(root->s_pmap, i);
-	}
-
+	pmap_remove_range(root->s_pmap, base, limit - base);
+	pmap_flush();
 	return KERN_OK;
 }
 
@@ -939,10 +935,11 @@ static kern_status_t delete_area(
 	       mapping->vma_limit,
 	       mapping->vma_limit - mapping->vma_base);
 
-	for (size_t i = mapping->vma_base; i < mapping->vma_limit;
-	     i += VM_PAGE_SIZE) {
-		pmap_remove(root->s_pmap, i);
-	}
+	pmap_remove_range(
+		root->s_pmap,
+		mapping->vma_base,
+		mapping->vma_limit - mapping->vma_base);
+	pmap_flush();
 
 	struct vm_object *object = mapping->vma_object;
 	unsigned long flags;
@@ -1214,6 +1211,7 @@ static struct vm_area *area_duplicate(struct vm_area *area)
 	}
 
 	out->vma_prot = area->vma_prot;
+	out->vma_flags = area->vma_flags;
 	out->vma_object_offset = area->vma_object_offset;
 	out->vma_base = area->vma_base;
 	out->vma_limit = area->vma_limit;
@@ -1280,7 +1278,8 @@ static kern_status_t prepare_duplicate_areas(
 		struct vm_object *src_vmo = tmp_area->vma_object;
 		vm_object_lock(src_vmo);
 
-		struct vm_object *dest_vmo = NULL;
+		struct vm_object *dest_vmo_link = NULL;
+		struct vm_object *dest_vmo_cow = NULL;
 		struct queue_entry *cur_entry
 			= queue_first(&src_vmo->vo_mappings);
 
@@ -1311,6 +1310,13 @@ static kern_status_t prepare_duplicate_areas(
 				continue;
 			}
 
+			struct vm_object *dest_vmo = NULL;
+			if (src_area->vma_flags & VM_SHARED) {
+				dest_vmo = dest_vmo_link;
+			} else {
+				dest_vmo = dest_vmo_cow;
+			}
+
 			if (!dest_vmo) {
 				tracek("[%zx-%zx %x] creating COW duplicate of "
 				       "vmo %p",
@@ -1318,7 +1324,18 @@ static kern_status_t prepare_duplicate_areas(
 				       src_area->vma_limit,
 				       src_area->vma_prot,
 				       src_vmo);
-				dest_vmo = vm_object_duplicate_cow(src_vmo);
+
+				if (src_area->vma_flags & VM_SHARED) {
+					dest_vmo_link = src_vmo;
+					object_ref(&dest_vmo_link->vo_base);
+
+					dest_vmo = dest_vmo_link;
+				} else {
+					dest_vmo_cow = vm_object_duplicate_cow(
+						src_vmo);
+					dest_vmo = dest_vmo_cow;
+				}
+
 				tracek("[%zx-%zx %x] created COW duplicate of "
 				       "vmo %p -> %p",
 				       src_area->vma_base,
@@ -1328,11 +1345,20 @@ static kern_status_t prepare_duplicate_areas(
 				       dest_vmo);
 			}
 
+			object_ref(&dest_vmo->vo_base);
 			dest_area->vma_object = dest_vmo;
 			update_area_pte_cow(src, dest, src_area);
 			cur_entry = queue_next(cur_entry);
 		}
 
+		if (dest_vmo_link) {
+			object_unref(&dest_vmo_link->vo_base);
+		}
+
+		if (dest_vmo_cow) {
+			object_unref(&dest_vmo_cow->vo_base);
+		}
+
 		vm_object_unlock(src_vmo);
 
 		cur_node = btree_next(cur_node);
@@ -1502,6 +1528,17 @@ static kern_status_t request_missing_page(
 	vm_object_lock(object);
 	address_space_unlock(region);
 
+	kern_status_t status = KERN_OK;
+
+	if (object->vo_flags & VMO_LAZY_ATTACH) {
+		status = vm_object_attach_cow(object, irq_flags);
+	}
+
+	if (status != KERN_OK) {
+		vm_object_unlock_irqrestore(object, *irq_flags);
+		return status;
+	}
+
 	struct vm_page *pg = vm_object_get_page(
 		object,
 		object_offset,
@@ -1515,7 +1552,7 @@ static kern_status_t request_missing_page(
 
 	/* now: `region` is unlocked, and `object` is locked */
 
-	kern_status_t status = pmap_add(
+	status = pmap_add(
 		region->s_pmap,
 		addr,
 		vm_page_get_pfn(pg),
@@ -1550,9 +1587,6 @@ static kern_status_t handle_cow_access(
 	}
 
 	tracek("cow access %zx", addr);
-	if (area->vma_object->vo_ctrl) {
-		panic("COW on controlled vm-object");
-	}
 
 	off_t object_offset = addr - area->vma_base + area->vma_object_offset;
 	vm_object_lock(area->vma_object);
@@ -1663,7 +1697,7 @@ kern_status_t address_space_demand_map(
 	address_space_lock_irqsave(region, &irq_flags);
 
 	const enum pmap_fault_flags cow_flags
-		= PMAP_FAULT_WRITE | PMAP_FAULT_PRESENT | PMAP_FAULT_USER;
+		= PMAP_FAULT_WRITE | PMAP_FAULT_PRESENT;
 
 	if ((flags & cow_flags) == cow_flags) {
 		return handle_cow_access(region, addr, flags, &irq_flags);

vm/bootstrap.c

@@ -6,7 +6,7 @@
 #include <kernel/vm-object.h>
 #include <kernel/vm.h>
 #include <limits.h>
-#include <mango/status.h>
+#include <magenta/status.h>
 #include <stddef.h>
 #include <stdint.h>
 

vm/vm-controller.c

@@ -4,18 +4,17 @@
 #include <kernel/util.h>
 #include <kernel/vm-controller.h>
 #include <kernel/vm-object.h>
-#include <mango/signal.h>
+#include <magenta/signal.h>
 
 #define VM_CONTROLLER_CAST(p)                                                  \
 	OBJECT_C_CAST(struct vm_controller, vc_base, &vm_controller_type, p)
 
-BTREE_DEFINE_SIMPLE_INSERT(struct vm_object, vo_ctrl_node, vo_key, put_object)
 BTREE_DEFINE_SIMPLE_GET(
-	struct vm_object,
-	equeue_key_t,
-	vo_ctrl_node,
-	vo_key,
-	get_object)
+	struct vm_request,
+	uint64_t,
+	req_node,
+	req_id,
+	get_request)
 
 static struct object_type vm_controller_type = {
 	.ob_name = "vm-controller",
@@ -23,14 +22,14 @@ static struct object_type vm_controller_type = {
 	.ob_header_offset = offsetof(struct vm_controller, vc_base),
 };
 
-static struct vm_cache page_request_cache = {
-	.c_name = "page-request",
-	.c_obj_size = sizeof(struct page_request),
+static struct vm_cache vm_request_cache = {
+	.c_name = "vm-request",
+	.c_obj_size = sizeof(struct vm_request),
 };
 
 kern_status_t vm_controller_type_init(void)
 {
-	vm_cache_init(&page_request_cache);
+	vm_cache_init(&vm_request_cache);
 	return object_type_register(&vm_controller_type);
 }
 
@@ -51,19 +50,19 @@ struct vm_controller *vm_controller_create(void)
 	return ctrl;
 }
 
-static struct page_request *get_next_request(struct vm_controller *ctrl)
+static struct vm_request *get_next_request(struct vm_controller *ctrl)
 {
 	struct btree_node *cur = btree_first(&ctrl->vc_requests);
 	while (cur) {
-		struct page_request *req
-			= BTREE_CONTAINER(struct page_request, req_node, cur);
+		struct vm_request *req
+			= BTREE_CONTAINER(struct vm_request, req_node, cur);
 		spin_lock(&req->req_lock);
 		switch (req->req_status) {
-		case PAGE_REQUEST_PENDING:
-			req->req_status = PAGE_REQUEST_IN_PROGRESS;
+		case VM_REQUEST_PENDING:
+			req->req_status = VM_REQUEST_IN_PROGRESS;
 			ctrl->vc_requests_waiting--;
 			return req;
-		case PAGE_REQUEST_ASYNC:
+		case VM_REQUEST_ASYNC:
 			btree_delete(&ctrl->vc_requests, &req->req_node);
 			ctrl->vc_requests_waiting--;
 			return req;
@@ -78,7 +77,7 @@ static struct page_request *get_next_request(struct vm_controller *ctrl)
 	return NULL;
 }
 
-static kern_status_t try_enqueue(struct btree *tree, struct page_request *req)
+static kern_status_t try_enqueue(struct btree *tree, struct vm_request *req)
 {
 	if (!tree->b_root) {
 		tree->b_root = &req->req_node;
@@ -88,8 +87,8 @@ static kern_status_t try_enqueue(struct btree *tree, struct page_request *req)
 
 	struct btree_node *cur = tree->b_root;
 	while (1) {
-		struct page_request *cur_node
-			= BTREE_CONTAINER(struct page_request, req_node, cur);
+		struct vm_request *cur_node
+			= BTREE_CONTAINER(struct vm_request, req_node, cur);
 		struct btree_node *next = NULL;
 
 		if (req->req_id > cur_node->req_id) {
@@ -119,7 +118,7 @@ static kern_status_t try_enqueue(struct btree *tree, struct page_request *req)
 
 static kern_status_t send_request_async(
 	struct vm_controller *ctrl,
-	struct page_request *req)
+	struct vm_request *req)
 {
 	fill_random(&req->req_id, sizeof req->req_id);
 	while (!try_enqueue(&ctrl->vc_requests, req)) {
@@ -136,9 +135,9 @@ static kern_status_t send_request_async(
 
 kern_status_t vm_controller_recv(
 	struct vm_controller *ctrl,
-	equeue_packet_page_request_t *out)
+	equeue_packet_vm_request_t *out)
 {
-	struct page_request *req = NULL;
+	struct vm_request *req = NULL;
 
 	req = get_next_request(ctrl);
 	if (!req) {
@@ -151,16 +150,30 @@ kern_status_t vm_controller_recv(
 			VM_CONTROLLER_SIGNAL_REQUEST_RECEIVED);
 	}
 
-	out->req_vmo = req->req_object;
+	vm_object_lock(req->req_object);
+	out->req_id = req->req_id;
+	out->req_vmo = req->req_object->vo_key;
 	out->req_type = req->req_type;
-	out->req_offset = req->req_offset;
-	out->req_length = req->req_length;
 
+	switch (req->req_type) {
+	case VM_REQUEST_READ:
+	case VM_REQUEST_DIRTY:
+		out->req_offset = req->req_offset;
+		out->req_length = req->req_length;
+		break;
+	case VM_REQUEST_ATTACH:
+		out->req_src_vmo = req->req_object->vo_key;
+		break;
+	default:
+		break;
+	}
+
+	vm_object_unlock(req->req_object);
 	spin_unlock(&req->req_lock);
 
-	if (req->req_status == PAGE_REQUEST_ASYNC) {
+	if (req->req_status == VM_REQUEST_ASYNC) {
 		put_current_thread(req->req_sender);
-		vm_cache_free(&page_request_cache, req);
+		vm_cache_free(&vm_request_cache, req);
 	}
 
 	return KERN_OK;
@@ -208,6 +221,52 @@ kern_status_t vm_controller_create_object(
 	return KERN_OK;
 }
 
+kern_status_t vm_controller_prepare_attach(
+	struct vm_controller *ctrl,
+	uint64_t req_id,
+	struct vm_object **out_vmo)
+{
+	struct vm_request *req = get_request(&ctrl->vc_requests, req_id);
+	if (!req) {
+		return KERN_INVALID_ARGUMENT;
+	}
+
+	spin_lock(&req->req_lock);
+	req->req_status = VM_REQUEST_IN_PROGRESS;
+	*out_vmo = req->req_object;
+	spin_unlock(&req->req_lock);
+
+	return KERN_OK;
+}
+
+kern_status_t vm_controller_finish_attach(
+	struct vm_controller *ctrl,
+	uint64_t req_id,
+	equeue_key_t new_key)
+{
+	struct vm_request *req = get_request(&ctrl->vc_requests, req_id);
+	if (!req) {
+		return KERN_INVALID_ARGUMENT;
+	}
+
+	spin_lock(&req->req_lock);
+	struct vm_object *vmo = req->req_object;
+	spin_unlock(&req->req_lock);
+
+	vm_object_lock(vmo);
+	vmo->vo_key = new_key;
+	vmo->vo_flags &= ~VMO_LAZY_ATTACH;
+	vm_object_unlock(vmo);
+
+	spin_lock(&req->req_lock);
+	req->req_status = VM_REQUEST_COMPLETE;
+	req->req_result = KERN_OK;
+	thread_awaken(req->req_sender);
+	spin_unlock(&req->req_lock);
+
+	return KERN_OK;
+}
+
 kern_status_t vm_controller_detach_object(
 	struct vm_controller *ctrl,
 	struct vm_object *vmo)
@@ -216,7 +275,7 @@ kern_status_t vm_controller_detach_object(
 		return KERN_INVALID_ARGUMENT;
 	}
 
-	if (vmo->vo_key == 0) {
+	if (vmo->vo_flags & VMO_LAZY_ATTACH) {
 		/* this vmo isn't actually attached to this controller yet.
 		 * this can happen if a controller-attached vmo was duplicated
 		 * via copy-on-write, and the duplicate vmo has not yet been
@@ -225,16 +284,14 @@ kern_status_t vm_controller_detach_object(
 		return KERN_OK;
 	}
 
-	struct page_request *req
-		= vm_cache_alloc(&page_request_cache, VM_NORMAL);
-	req->req_type = PAGE_REQUEST_DETACH;
-	req->req_status = PAGE_REQUEST_ASYNC;
-	req->req_object = vmo->vo_key;
+	struct vm_request *req = vm_cache_alloc(&vm_request_cache, VM_NORMAL);
+	req->req_type = VM_REQUEST_DETACH;
+	req->req_status = VM_REQUEST_ASYNC;
+	req->req_object = vmo;
 	req->req_sender = get_current_thread();
 	send_request_async(ctrl, req);
 
 	vmo->vo_ctrl = NULL;
-	vmo->vo_key = 0;
 	object_unref(&ctrl->vc_base);
 
 	return KERN_OK;
@@ -242,7 +299,7 @@ kern_status_t vm_controller_detach_object(
 
 static void wait_for_reply(
 	struct vm_controller *ctrl,
-	struct page_request *req,
+	struct vm_request *req,
 	unsigned long *lock_flags)
 {
 	struct wait_item waiter;
@@ -251,7 +308,7 @@ static void wait_for_reply(
 	wait_item_init(&waiter, self);
 	for (;;) {
 		self->tr_state = THREAD_SLEEPING;
-		if (req->req_status == PAGE_REQUEST_COMPLETE) {
+		if (req->req_status == VM_REQUEST_COMPLETE) {
 			break;
 		}
 
@@ -264,7 +321,7 @@ static void wait_for_reply(
 	put_current_thread(self);
 }
 
-static void fulfill_requests(
+void vm_controller_fulfill_requests(
 	struct vm_controller *ctrl,
 	equeue_key_t object,
 	off_t offset,
@@ -274,8 +331,8 @@ static void fulfill_requests(
 	off_t limit = offset + length - 1;
 	struct btree_node *cur = btree_first(&ctrl->vc_requests);
 	while (cur) {
-		struct page_request *req
-			= BTREE_CONTAINER(struct page_request, req_node, cur);
+		struct vm_request *req
+			= BTREE_CONTAINER(struct vm_request, req_node, cur);
 		spin_lock(&req->req_lock);
 		bool match = false;
 		off_t req_base = req->req_offset;
@@ -287,12 +344,14 @@ static void fulfill_requests(
 			match = true;
 		}
 
-		if (req->req_object != object) {
+		vm_object_lock(req->req_object);
+		if (req->req_object->vo_key != object) {
 			match = false;
 		}
+		vm_object_unlock(req->req_object);
 
 		if (match) {
-			req->req_status = PAGE_REQUEST_COMPLETE;
+			req->req_status = VM_REQUEST_COMPLETE;
 			req->req_result = result;
 			thread_awaken(req->req_sender);
 		}
@@ -325,14 +384,13 @@ kern_status_t vm_controller_supply_pages(
 		src_offset,
 		count,
 		NULL);
-	fulfill_requests(ctrl, dst->vo_key, dst_offset, count, status);
 
 	return status;
 }
 
 kern_status_t vm_controller_send_request(
 	struct vm_controller *ctrl,
-	struct page_request *req,
+	struct vm_request *req,
 	unsigned long *irq_flags)
 {
 	fill_random(&req->req_id, sizeof req->req_id);

vm/vm-object.c

@@ -288,8 +288,9 @@ struct vm_object *vm_object_duplicate_cow(struct vm_object *vmo)
 	struct vm_object *out = VM_OBJECT_CAST(obj);
 
 	memcpy(out->vo_name, vmo->vo_name, sizeof out->vo_name);
-	out->vo_flags = vmo->vo_flags;
+	out->vo_flags = vmo->vo_flags | VMO_LAZY_ATTACH;
 	out->vo_ctrl = vmo->vo_ctrl;
+	out->vo_key = vmo->vo_key;
 	out->vo_prot = vmo->vo_prot;
 	out->vo_size = vmo->vo_size;
 	memcpy(out->vo_name, vmo->vo_name, sizeof vmo->vo_name);
@@ -315,6 +316,37 @@ struct vm_object *vm_object_duplicate_cow(struct vm_object *vmo)
 	return out;
 }
 
+kern_status_t vm_object_attach_cow(
+	struct vm_object *vmo,
+	unsigned long *irq_flags)
+{
+	struct vm_controller *ctrl = vmo->vo_ctrl;
+	struct vm_request req = {0};
+	req.req_status = VM_REQUEST_PENDING;
+	req.req_type = VM_REQUEST_ATTACH;
+	req.req_length = vm_page_order_to_bytes(VM_PAGE_4K);
+	req.req_sender = get_current_thread();
+
+	object_ref(&vmo->vo_base);
+	req.req_object = vmo;
+
+	vm_object_unlock_irqrestore(vmo, *irq_flags);
+	vm_controller_lock_irqsave(ctrl, irq_flags);
+
+	spin_lock(&req.req_lock);
+
+	kern_status_t status
+		= vm_controller_send_request(ctrl, &req, irq_flags);
+
+	put_current_thread(req.req_sender);
+	spin_unlock(&req.req_lock);
+	vm_controller_unlock_irqrestore(ctrl, *irq_flags);
+	object_unref(&vmo->vo_base);
+	vm_object_lock_irqsave(vmo, irq_flags);
+
+	return status;
+}
+
 static struct vm_page *alloc_page(struct vm_object *vo, off_t offset)
 {
 	struct vm_page *page = NULL;
@@ -458,15 +490,15 @@ static kern_status_t request_page(
 	unsigned long *irq_flags)
 {
 	struct vm_controller *ctrl = vo->vo_ctrl;
-	struct page_request req = {0};
-	req.req_status = PAGE_REQUEST_PENDING;
-	req.req_type = PAGE_REQUEST_READ;
+	struct vm_request req = {0};
+	req.req_status = VM_REQUEST_PENDING;
+	req.req_type = VM_REQUEST_READ;
 	req.req_offset = offset;
 	req.req_length = vm_page_order_to_bytes(VM_PAGE_4K);
 	req.req_sender = get_current_thread();
 
 	object_ref(&vo->vo_base);
-	req.req_object = vo->vo_key;
+	req.req_object = vo;
 
 	vm_object_unlock_irqrestore(vo, *irq_flags);
 	vm_controller_lock_irqsave(ctrl, irq_flags);
@@ -484,6 +516,33 @@ static kern_status_t request_page(
 	return status;
 }
 
+kern_status_t vm_object_prefetch(
+	struct vm_object *vo,
+	off_t offset,
+	size_t length,
+	unsigned long *irq_flags)
+{
+	offset &= ~VM_PAGE_MASK;
+	if (length & VM_PAGE_MASK) {
+		length &= ~VM_PAGE_MASK;
+		length += VM_PAGE_SIZE;
+	}
+
+	for (off_t i = offset; i < offset + length; i += VM_PAGE_SIZE) {
+		struct vm_page *pg = vm_object_get_page(
+			vo,
+			i,
+			VMO_ALLOCATE_MISSING_PAGE | VMO_REQUEST_MISSING_PAGE,
+			irq_flags);
+		if (!pg) {
+			/* TODO get error code from vm_object_get_page */
+			return KERN_NO_MEMORY;
+		}
+	}
+
+	return KERN_OK;
+}
+
 struct vm_page *vm_object_get_page(
 	struct vm_object *vo,
 	off_t offset,