diff mbox

[3/3] kvm tools: add virtio console support v2

Message ID 1302228309-6583-3-git-send-email-asias.hejun@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Asias He April 8, 2011, 2:05 a.m. UTC
- Consolidate all console related code to term.c
- Use timer based approach instead of thread to deal with user input
- Introduce --enable-virtio-console option, this option disables
  serial console output

NOTE:
Please add something like this:
T2:23:respawn:/sbin/getty -L hvc0 9600 vt100
to your /etc/inittab file to get a virtio console login.

Signed-off-by: Asias He <asias.hejun@gmail.com>
---
 tools/kvm/8250-serial.c                |   40 +-----
 tools/kvm/Makefile                     |    2 +
 tools/kvm/console-virtio.c             |  218 ++++++++++++++++++++++++++++++++
 tools/kvm/include/kvm/8250-serial.h    |    2 +-
 tools/kvm/include/kvm/console-virtio.h |    9 ++
 tools/kvm/include/kvm/term.h           |   17 +++
 tools/kvm/main.c                       |   48 ++-----
 tools/kvm/term.c                       |   89 +++++++++++++
 8 files changed, 357 insertions(+), 68 deletions(-)
 create mode 100644 tools/kvm/console-virtio.c
 create mode 100644 tools/kvm/include/kvm/console-virtio.h
 create mode 100644 tools/kvm/include/kvm/term.h
 create mode 100644 tools/kvm/term.c

Comments

Pekka Enberg April 7, 2011, 5:50 a.m. UTC | #1
Hi Asias,

On 4/8/11 5:05 AM, Asias He wrote:
> - Consolidate all console related code to term.c
> - Use timer based approach instead of thread to deal with user input
> - Introduce --enable-virtio-console option, this option disables
>    serial console output
>
> NOTE:
> Please add something like this:
> T2:23:respawn:/sbin/getty -L hvc0 9600 vt100
> to your /etc/inittab file to get a virtio console login.
>
> Signed-off-by: Asias He<asias.hejun@gmail.com>
> ---
>   tools/kvm/8250-serial.c                |   40 +-----
>   tools/kvm/Makefile                     |    2 +
>   tools/kvm/console-virtio.c             |  218 ++++++++++++++++++++++++++++++++
>   tools/kvm/include/kvm/8250-serial.h    |    2 +-
>   tools/kvm/include/kvm/console-virtio.h |    9 ++
>   tools/kvm/include/kvm/term.h           |   17 +++
>   tools/kvm/main.c                       |   48 ++-----
>   tools/kvm/term.c                       |   89 +++++++++++++

Is it too much trouble to ask you to split this patch into two: (1) the 
term.c refactoring and (2) virtio console implementation? That would 
make the series much easier to review.

                 Pekka
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Asias He April 8, 2011, 2:18 p.m. UTC | #2
On 04/07/2011 01:50 PM, Pekka Enberg wrote:
> Hi Asias,
> 
> On 4/8/11 5:05 AM, Asias He wrote:
>> - Consolidate all console related code to term.c
>> - Use timer based approach instead of thread to deal with user input
>> - Introduce --enable-virtio-console option, this option disables
>>    serial console output
>>
>> NOTE:
>> Please add something like this:
>> T2:23:respawn:/sbin/getty -L hvc0 9600 vt100
>> to your /etc/inittab file to get a virtio console login.
>>
>> Signed-off-by: Asias He<asias.hejun@gmail.com>
>> ---
>>   tools/kvm/8250-serial.c                |   40 +-----
>>   tools/kvm/Makefile                     |    2 +
>>   tools/kvm/console-virtio.c             |  218
>> ++++++++++++++++++++++++++++++++
>>   tools/kvm/include/kvm/8250-serial.h    |    2 +-
>>   tools/kvm/include/kvm/console-virtio.h |    9 ++
>>   tools/kvm/include/kvm/term.h           |   17 +++
>>   tools/kvm/main.c                       |   48 ++-----
>>   tools/kvm/term.c                       |   89 +++++++++++++
> 
> Is it too much trouble to ask you to split this patch into two: (1) the
> term.c refactoring and (2) virtio console implementation? That would
> make the series much easier to review.
> 

Hi, Pekka

I have split the patch and sent it out.
diff mbox

Patch

diff --git a/tools/kvm/8250-serial.c b/tools/kvm/8250-serial.c
index 939e9f5..e92ff89 100644
--- a/tools/kvm/8250-serial.c
+++ b/tools/kvm/8250-serial.c
@@ -3,12 +3,11 @@ 
 #include "kvm/read-write.h"
 #include "kvm/ioport.h"
 #include "kvm/util.h"
+#include "kvm/term.h"
 #include "kvm/kvm.h"
 
 #include <linux/serial_reg.h>
 
-#include <stdbool.h>
-#include <poll.h>
 
 struct serial8250_device {
 	uint16_t		iobase;
@@ -54,26 +53,6 @@  static struct serial8250_device devices[] = {
 	},
 };
 
-static int read_char(int fd)
-{
-	char c;
-
-	if (read_in_full(fd, &c, 1) == 0)
-		return -1;
-
-	return c;
-}
-
-static bool is_readable(int fd)
-{
-	struct pollfd pollfd = (struct pollfd) {
-		.fd	= fd,
-		.events	= POLLIN,
-	};
-
-	return poll(&pollfd, 1, 0) > 0;
-}
-
 static void serial8250__receive(struct kvm *self, struct serial8250_device *dev)
 {
 	int c;
@@ -81,10 +60,11 @@  static void serial8250__receive(struct kvm *self, struct serial8250_device *dev)
 	if (dev->lsr & UART_LSR_DR)
 		return;
 
-	if (!is_readable(STDIN_FILENO))
+	if (!term_readable(CONSOLE_8250))
 		return;
 
-	c		= read_char(STDIN_FILENO);
+	c		= term_getc(CONSOLE_8250);
+
 	if (c < 0)
 		return;
 
@@ -95,7 +75,7 @@  static void serial8250__receive(struct kvm *self, struct serial8250_device *dev)
 /*
  * Interrupts are injected for ttyS0 only.
  */
-void serial8250__interrupt(struct kvm *self)
+void serial8250__inject_interrupt(struct kvm *self)
 {
 	struct serial8250_device *dev = &devices[0];
 
@@ -170,15 +150,9 @@  static bool serial8250_out(struct kvm *self, uint16_t port, void *data, int size
 	} else {
 		switch (offset) {
 		case UART_TX: {
-			char *p = data;
-			int i;
-
+			char *addr = data;
 			if (!(dev->mcr & UART_MCR_LOOP)) {
-				while (count--) {
-					for (i = 0; i < size; i++)
-						fprintf(stdout, "%c", *p++);
-				}
-				fflush(stdout);
+				term_putc(CONSOLE_8250, addr, size * count);
 			}
 			dev->iir		= UART_IIR_NO_INT;
 			break;
diff --git a/tools/kvm/Makefile b/tools/kvm/Makefile
index 747aa51..55f342d 100644
--- a/tools/kvm/Makefile
+++ b/tools/kvm/Makefile
@@ -14,6 +14,7 @@  TAGS = ctags
 
 OBJS	+= 8250-serial.o
 OBJS	+= blk-virtio.o
+OBJS	+= console-virtio.o
 OBJS	+= cpuid.o
 OBJS	+= read-write.o
 OBJS	+= disk-image.o
@@ -24,6 +25,7 @@  OBJS	+= main.o
 OBJS	+= mmio.o
 OBJS	+= pci.o
 OBJS	+= util.o
+OBJS	+= term.o
 
 DEPS	:= $(patsubst %.o,%.d,$(OBJS))
 
diff --git a/tools/kvm/console-virtio.c b/tools/kvm/console-virtio.c
new file mode 100644
index 0000000..366d0ab
--- /dev/null
+++ b/tools/kvm/console-virtio.c
@@ -0,0 +1,218 @@ 
+#include "kvm/console-virtio.h"
+#include "kvm/virtio_pci.h"
+#include "kvm/disk-image.h"
+#include "kvm/virtqueue.h"
+#include "kvm/ioport.h"
+#include "kvm/util.h"
+#include "kvm/term.h"
+#include "kvm/kvm.h"
+#include "kvm/pci.h"
+
+#include <linux/virtio_console.h>
+#include <linux/virtio_ring.h>
+#include <linux/virtio_blk.h>
+
+#include <sys/uio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <inttypes.h>
+#include <termios.h>
+#include <assert.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#define VIRTIO_CONSOLE_IRQ		14
+#define VIRTIO_CONSOLE_QUEUE_SIZE	128
+#define VIRTIO_CONSOLE_NUM_QUEUES	2
+#define VIRTIO_CONSOLE_RX_QUEUE		0
+#define VIRTIO_CONSOLE_TX_QUEUE		1
+#define PCI_VIRTIO_CONSOLE_DEVNUM	2
+
+struct console_device {
+	struct virt_queue		vqs[VIRTIO_CONSOLE_NUM_QUEUES];
+	struct virtio_console_config	console_config;
+	uint32_t			host_features;
+	uint32_t			guest_features;
+	uint16_t			config_vector;
+	uint8_t				status;
+	uint16_t			queue_selector;
+};
+
+static struct console_device console_device = {
+	.console_config = {
+		.cols		= 80,
+		.rows		= 24,
+		.max_nr_ports	= 1,
+	},
+
+	.host_features		= 0,
+};
+
+/*
+ * Interrupts are injected for hvc0 only.
+ */
+void virtio_console__inject_interrupt(struct kvm *self)
+{
+	struct iovec iov[VIRTIO_CONSOLE_QUEUE_SIZE];
+	struct virt_queue *vq;
+	uint16_t out, in;
+	uint16_t head;
+	int len;
+
+	vq = &console_device.vqs[VIRTIO_CONSOLE_RX_QUEUE];
+
+	if (term_readable(CONSOLE_VIRTIO) && virt_queue__available(vq)) {
+		head = virt_queue__get_iov(vq, iov, &out, &in, self);
+		len = term_getc_iov(CONSOLE_VIRTIO, iov, in);
+		virt_queue__set_used_elem(vq, head, len);
+		kvm__irq_line(self, VIRTIO_CONSOLE_IRQ, 1);
+	}
+}
+
+static bool virtio_console_pci_io_device_specific_in(void *data, unsigned long offset, int size, uint32_t count)
+{
+	uint8_t *config_space = (uint8_t *) &console_device.console_config;
+
+	if (size != 1 || count != 1)
+		return false;
+
+	if ((offset - VIRTIO_PCI_CONFIG_NOMSI) > sizeof(struct virtio_console_config))
+		error("config offset is too big: %li", offset - VIRTIO_PCI_CONFIG_NOMSI);
+
+	ioport__write8(data, config_space[offset - VIRTIO_PCI_CONFIG_NOMSI]);
+
+	return true;
+}
+
+static bool virtio_console_pci_io_in(struct kvm *self, uint16_t port, void *data, int size, uint32_t count)
+{
+	unsigned long offset = port - IOPORT_VIRTIO_CONSOLE;
+
+	switch (offset) {
+	case VIRTIO_PCI_HOST_FEATURES:
+		ioport__write32(data, console_device.host_features);
+		break;
+	case VIRTIO_PCI_GUEST_FEATURES:
+		return false;
+	case VIRTIO_PCI_QUEUE_PFN:
+		ioport__write32(data, console_device.vqs[console_device.queue_selector].pfn);
+		break;
+	case VIRTIO_PCI_QUEUE_NUM:
+		ioport__write16(data, VIRTIO_CONSOLE_QUEUE_SIZE);
+		break;
+	case VIRTIO_PCI_QUEUE_SEL:
+	case VIRTIO_PCI_QUEUE_NOTIFY:
+		return false;
+	case VIRTIO_PCI_STATUS:
+		ioport__write8(data, console_device.status);
+		break;
+	case VIRTIO_PCI_ISR:
+		ioport__write8(data, 0x1);
+		kvm__irq_line(self, VIRTIO_CONSOLE_IRQ, 0);
+		break;
+	case VIRTIO_MSI_CONFIG_VECTOR:
+		ioport__write16(data, console_device.config_vector);
+		break;
+	default:
+		return virtio_console_pci_io_device_specific_in(data, offset, size, count);
+	};
+
+	return true;
+}
+
+static void virtio_console_handle_callback(struct kvm *self, uint16_t queue_index) 
+{
+	struct iovec iov[VIRTIO_CONSOLE_QUEUE_SIZE];
+	struct virt_queue *vq;
+	uint16_t out, in;
+	uint16_t head;
+	uint32_t len;
+
+	vq = &console_device.vqs[queue_index];
+
+	if (queue_index == VIRTIO_CONSOLE_TX_QUEUE) {
+
+		while (virt_queue__available(vq)) {
+			head = virt_queue__get_iov(vq, iov, &out, &in, self);
+			len = term_putc_iov(CONSOLE_VIRTIO, iov, out);
+			virt_queue__set_used_elem(vq, head, len);
+		}
+
+		kvm__irq_line(self, VIRTIO_CONSOLE_IRQ, 1);
+	}
+}
+
+static bool virtio_console_pci_io_out(struct kvm *self, uint16_t port, void *data, int size, uint32_t count)
+{
+	unsigned long offset = port - IOPORT_VIRTIO_CONSOLE;
+
+	switch (offset) {
+	case VIRTIO_PCI_GUEST_FEATURES:
+		console_device.guest_features	= ioport__read32(data);
+		break;
+	case VIRTIO_PCI_QUEUE_PFN: {
+		struct virt_queue *queue;
+		void *p;
+
+		assert(console_device.queue_selector < VIRTIO_CONSOLE_NUM_QUEUES);
+
+		queue		= &console_device.vqs[console_device.queue_selector];
+		queue->pfn	= ioport__read32(data);
+		p		= guest_flat_to_host(self, queue->pfn << 12);
+
+		vring_init(&queue->vring, VIRTIO_CONSOLE_QUEUE_SIZE, p, 4096);
+
+		break;
+	}
+	case VIRTIO_PCI_QUEUE_SEL:
+		console_device.queue_selector	= ioport__read16(data);
+		break;
+	case VIRTIO_PCI_QUEUE_NOTIFY: {
+		uint16_t queue_index;
+		queue_index	= ioport__read16(data);
+		virtio_console_handle_callback(self, queue_index);
+		break;
+	}
+	case VIRTIO_PCI_STATUS:
+		console_device.status		= ioport__read8(data);
+		break;
+	case VIRTIO_MSI_CONFIG_VECTOR:
+		console_device.config_vector	= VIRTIO_MSI_NO_VECTOR;
+		break;
+	case VIRTIO_MSI_QUEUE_VECTOR:
+		break;
+	default:
+		return false;
+	};
+
+	return true;
+}
+
+static struct ioport_operations virtio_console_io_ops = {
+	.io_in	= virtio_console_pci_io_in,
+	.io_out	= virtio_console_pci_io_out,
+};
+
+#define PCI_VENDOR_ID_REDHAT_QUMRANET		0x1af4
+#define PCI_DEVICE_ID_VIRTIO_CONSOLE		0x1002
+#define PCI_SUBSYSTEM_VENDOR_ID_REDHAT_QUMRANET	0x1af4
+#define PCI_SUBSYSTEM_ID_VIRTIO_CONSOLE		0x0003
+
+static struct pci_device_header virtio_console_pci_device = {
+	.vendor_id		= PCI_VENDOR_ID_REDHAT_QUMRANET,
+	.device_id		= PCI_DEVICE_ID_VIRTIO_CONSOLE,
+	.header_type		= PCI_HEADER_TYPE_NORMAL,
+	.revision_id		= 0,
+	.class			= (0x07 << 8) | (0x80 << 4) | (0x0 << 0),
+	.subsys_vendor_id	= PCI_SUBSYSTEM_VENDOR_ID_REDHAT_QUMRANET,
+	.subsys_id		= PCI_SUBSYSTEM_ID_VIRTIO_CONSOLE,
+	.bar[0]			= IOPORT_VIRTIO_CONSOLE | PCI_BASE_ADDRESS_SPACE_IO,
+	.irq_pin		= 3,
+	.irq_line		= VIRTIO_CONSOLE_IRQ,
+};
+
+void virtio_console__init(struct kvm *self)
+{
+	pci__register(&virtio_console_pci_device, PCI_VIRTIO_CONSOLE_DEVNUM);
+	ioport__register(IOPORT_VIRTIO_CONSOLE, &virtio_console_io_ops, IOPORT_VIRTIO_CONSOLE_SIZE);
+}
diff --git a/tools/kvm/include/kvm/8250-serial.h b/tools/kvm/include/kvm/8250-serial.h
index 05ee096..73ed078 100644
--- a/tools/kvm/include/kvm/8250-serial.h
+++ b/tools/kvm/include/kvm/8250-serial.h
@@ -4,6 +4,6 @@ 
 struct kvm;
 
 void serial8250__init(struct kvm *kvm);
-void serial8250__interrupt(struct kvm *kvm);
+void serial8250__inject_interrupt(struct kvm *kvm);
 
 #endif /* KVM__8250_SERIAL_H */
diff --git a/tools/kvm/include/kvm/console-virtio.h b/tools/kvm/include/kvm/console-virtio.h
new file mode 100644
index 0000000..d2e5d19
--- /dev/null
+++ b/tools/kvm/include/kvm/console-virtio.h
@@ -0,0 +1,9 @@ 
+#ifndef KVM__CONSOLE_VIRTIO_H
+#define KVM__CONSOLE_VIRTIO_H
+
+struct kvm;
+
+void virtio_console__init(struct kvm *self);
+void virtio_console__inject_interrupt(struct kvm *self);
+
+#endif /* KVM__CONSOLE_VIRTIO_H */
diff --git a/tools/kvm/include/kvm/term.h b/tools/kvm/include/kvm/term.h
new file mode 100644
index 0000000..4d580e1
--- /dev/null
+++ b/tools/kvm/include/kvm/term.h
@@ -0,0 +1,17 @@ 
+#ifndef KVM__TERM_H
+#define KVM__TERM_H
+
+#include <sys/uio.h>
+
+#define CONSOLE_8250	1
+#define CONSOLE_VIRTIO	2
+
+int term_putc_iov(int who, struct iovec *iov, int iovcnt);
+int term_getc_iov(int who, struct iovec *iov, int iovcnt);
+int term_putc(int who, char *addr, int cnt);
+int term_getc(int who);
+
+bool term_readable(int who);
+void term_init(void);
+
+#endif /* KVM__TERM_H */
diff --git a/tools/kvm/main.c b/tools/kvm/main.c
index 7beb6a6..5bcefde 100644
--- a/tools/kvm/main.c
+++ b/tools/kvm/main.c
@@ -2,12 +2,13 @@ 
 
 #include "kvm/8250-serial.h"
 #include "kvm/blk-virtio.h"
+#include "kvm/console-virtio.h"
 #include "kvm/disk-image.h"
 #include "kvm/util.h"
 #include "kvm/pci.h"
+#include "kvm/term.h"
 
 #include <inttypes.h>
-#include <termios.h>
 #include <signal.h>
 #include <stdint.h>
 #include <stdlib.h>
@@ -16,11 +17,12 @@ 
 #include <stdio.h>
 
 extern bool ioport_debug;
+extern int active_console;
 
 static void usage(char *argv[])
 {
 	fprintf(stderr, "  usage: %s "
-		"[--single-step] [--ioport-debug] "
+		"[--single-step] [--ioport-debug] [--enable-virtio-console] "
 		"[--kvm-dev=<device>] [--mem=<size-in-MiB>] [--params=<kernel-params>] "
 		"[--initrd=<initrd>] [--kernel=]<kernel-image> [--image=]<disk-image>\n",
 		argv[0]);
@@ -29,32 +31,6 @@  static void usage(char *argv[])
 
 static struct kvm *kvm;
 
-static struct termios orig_term;
-
-static void setup_console(void)
-{
-	struct termios term;
-
-	if (tcgetattr(STDIN_FILENO, &orig_term) < 0)
-		die("unable to save initial standard input settings");
-
-	term			= orig_term;
-
-	term.c_lflag		&= ~(ICANON|ECHO);
-
-	tcsetattr(STDIN_FILENO, TCSANOW, &term);
-}
-
-static void cleanup_console(void)
-{
-	tcsetattr(STDIN_FILENO, TCSANOW, &orig_term);
-}
-
-static void shutdown(void)
-{
-	cleanup_console();
-}
-
 static void handle_sigint(int sig)
 {
 	exit(1);
@@ -65,7 +41,6 @@  static void handle_sigquit(int sig)
 	kvm__show_registers(kvm);
 	kvm__show_code(kvm);
 	kvm__show_page_tables(kvm);
-
 	kvm__delete(kvm);
 
 	exit(1);
@@ -92,10 +67,6 @@  int main(int argc, char *argv[])
 	signal(SIGQUIT, handle_sigquit);
 	signal(SIGINT, handle_sigint);
 
-	setup_console();
-
-	atexit(shutdown);
-
 	for (i = 1; i < argc; i++) {
 		if (option_matches(argv[i], "--kernel=")) {
 			kernel_filename	= &argv[i][9];
@@ -115,6 +86,9 @@  int main(int argc, char *argv[])
 		} else if (option_matches(argv[i], "--single-step")) {
 			single_step	= true;
 			continue;
+		} else if (option_matches(argv[i], "--enable-virtio-console")) {
+			active_console	= CONSOLE_VIRTIO;
+			continue;
 		} else if (option_matches(argv[i], "--mem=")) {
 			unsigned long val = atol(&argv[i][6]) << 20;
 			if (val < ram_size)
@@ -138,6 +112,8 @@  int main(int argc, char *argv[])
 	if (!kernel_filename)
 		usage(argv);
 
+	term_init();
+
 	kvm = kvm__init(kvm_dev, ram_size);
 
 	if (image_filename) {
@@ -168,10 +144,13 @@  int main(int argc, char *argv[])
 		kvm__enable_singlestep(kvm);
 
 	serial8250__init(kvm);
+
 	pci__init();
 
 	blk_virtio__init(kvm);
 
+	virtio_console__init(kvm);
+
 	kvm__start_timer(kvm);
 
 	for (;;) {
@@ -210,7 +189,8 @@  int main(int argc, char *argv[])
 			break;
 		}
 		case KVM_EXIT_INTR: {
-			serial8250__interrupt(kvm);
+			serial8250__inject_interrupt(kvm);
+			virtio_console__inject_interrupt(kvm);
 			break;
 		}
 		case KVM_EXIT_SHUTDOWN:
diff --git a/tools/kvm/term.c b/tools/kvm/term.c
new file mode 100644
index 0000000..0ac53c0
--- /dev/null
+++ b/tools/kvm/term.c
@@ -0,0 +1,89 @@ 
+#include <poll.h>
+#include <stdbool.h>
+#include <termios.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/uio.h>
+
+#include "kvm/read-write.h"
+#include "kvm/term.h"
+#include "kvm/util.h"
+
+static struct termios orig_term;
+
+int active_console = CONSOLE_8250;
+
+int term_getc(int who)
+{
+	int c;
+
+	if (who != active_console)
+		return -1;
+
+	if (read_in_full(STDIN_FILENO, &c, 1) < 0)
+		return -1;
+	return c;
+}
+
+int term_putc(int who, char *addr, int cnt)
+{
+	if (who != active_console)
+		return -1;
+
+	while (cnt--) {
+		fprintf(stdout, "%c", *addr++);
+	}
+
+	fflush(stdout);
+	return cnt;
+}
+
+int term_getc_iov(int who, struct iovec *iov, int iovcnt)
+{
+	if (who != active_console)
+		return -1;
+
+	return readv(STDIN_FILENO, iov, iovcnt);
+}
+
+int term_putc_iov(int who, struct iovec *iov, int iovcnt)
+{
+	if (who != active_console)
+		return -1;
+
+	return writev(STDOUT_FILENO, iov, iovcnt);
+}
+
+bool term_readable(int who)
+{
+	struct pollfd pollfd = (struct pollfd) {
+		.fd	= STDIN_FILENO,
+		.events	= POLLIN,
+		.revents = 0,
+	};
+
+	if (who != active_console)
+		return false;
+
+	return poll(&pollfd, 1, 0) > 0;
+}
+
+static void term_cleanup(void)
+{
+	tcsetattr(STDIN_FILENO, TCSANOW, &orig_term);
+}
+
+void term_init(void)
+{
+	struct termios term;
+
+	if (tcgetattr(STDIN_FILENO, &orig_term) < 0)
+		die("unable to save initial standard input settings");
+
+	term = orig_term;
+	term.c_lflag &= ~(ICANON |ECHO | ISIG);
+	tcsetattr(STDIN_FILENO, TCSANOW, &term);
+
+	atexit(term_cleanup);
+}
+