On 09/15/2011 04:53 PM, Sasha Levin wrote:
> This patch adds the '-tty' option to 'kvm run' which allows the user to
> remap a guest TTY into a PTS on the host.
>
> Usage:
> 'kvm run --tty [id] [other options]'
>
> The tty will be mapped to a pts and will be printed on the screen:
> ' Info: Assigned terminal 1 to pty /dev/pts/X'
>
> At this point, it is possible to communicate with the guest using that pty.
>
> This is useful for debugging guest kernel using KGDB:
>
> 1. Run the guest:
> 'kvm run -k [vmlinuz] -p "kdbgoc=ttyS1 kdbgwait" --tty 1'
>
> And see which PTY got assigned to ttyS1.
>
> 2. Run GDB on the host:
> 'gdb [vmlinuz]'
>
> 3. Connect to the guest (from within GDB):
> 'target remote /dev/pty/X'
>
> 4. Start debugging! (enter 'continue' to continue boot).
>
> Cc: David Evensky <evensky@xxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Sasha Levin <levinsasha928@xxxxxxxxx>
> ---
> tools/kvm/Makefile | 1 +
> tools/kvm/builtin-run.c | 12 ++++++++
> tools/kvm/hw/serial.c | 46 ++++++++++++++++++--------------
> tools/kvm/include/kvm/term.h | 11 ++++---
> tools/kvm/term.c | 60 +++++++++++++++++++++++++++++++++--------
> tools/kvm/virtio/console.c | 6 ++--
> 6 files changed, 96 insertions(+), 40 deletions(-)
>
> diff --git a/tools/kvm/Makefile b/tools/kvm/Makefile
> index efa032d..fef624d 100644
> --- a/tools/kvm/Makefile
> +++ b/tools/kvm/Makefile
> @@ -115,6 +115,7 @@ OBJS += bios/bios-rom.o
>
> LIBS += -lrt
> LIBS += -lpthread
> +LIBS += -lutil
>
> # Additional ARCH settings for x86
> ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
> diff --git a/tools/kvm/builtin-run.c b/tools/kvm/builtin-run.c
> index 5dafb15..b5c63ca 100644
> --- a/tools/kvm/builtin-run.c
> +++ b/tools/kvm/builtin-run.c
> @@ -172,6 +172,15 @@ static int virtio_9p_rootdir_parser(const struct option *opt, const char *arg, i
> return 0;
> }
>
> +static int tty_parser(const struct option *opt, const char *arg, int unset)
> +{
> + int tty = atoi(arg);
> +
> + term_set_tty(tty);
> +
> + return 0;
> +}
> +
> static int shmem_parser(const struct option *opt, const char *arg, int unset)
> {
> const u64 default_size = SHMEM_DEFAULT_SIZE;
> @@ -316,6 +325,9 @@ static const struct option options[] = {
> OPT_STRING('\0', "console", &console, "serial or virtio",
> "Console to use"),
> OPT_STRING('\0', "dev", &dev, "device_file", "KVM device file"),
> + OPT_CALLBACK('\0', "tty", NULL, "tty id",
> + "Remap guest TTY into a pty on the host",
> + tty_parser),
>
> OPT_GROUP("Kernel options:"),
> OPT_STRING('k', "kernel", &kernel_filename, "kernel",
> diff --git a/tools/kvm/hw/serial.c b/tools/kvm/hw/serial.c
> index b3b233f..11fa5d4 100644
> --- a/tools/kvm/hw/serial.c
> +++ b/tools/kvm/hw/serial.c
> @@ -14,6 +14,7 @@
>
> struct serial8250_device {
> pthread_mutex_t mutex;
> + u8 id;
>
> u16 iobase;
> u8 irq;
> @@ -42,6 +43,7 @@ static struct serial8250_device devices[] = {
> [0] = {
> .mutex = PTHREAD_MUTEX_INITIALIZER,
>
> + .id = 0,
> .iobase = 0x3f8,
> .irq = 4,
>
> @@ -51,6 +53,7 @@ static struct serial8250_device devices[] = {
> [1] = {
> .mutex = PTHREAD_MUTEX_INITIALIZER,
>
> + .id = 1,
> .iobase = 0x2f8,
> .irq = 3,
>
> @@ -60,6 +63,7 @@ static struct serial8250_device devices[] = {
> [2] = {
> .mutex = PTHREAD_MUTEX_INITIALIZER,
>
> + .id = 2,
> .iobase = 0x3e8,
> .irq = 4,
>
> @@ -69,6 +73,7 @@ static struct serial8250_device devices[] = {
> [3] = {
> .mutex = PTHREAD_MUTEX_INITIALIZER,
>
> + .id = 3,
> .iobase = 0x2e8,
> .irq = 3,
>
> @@ -111,10 +116,10 @@ static void serial8250__receive(struct kvm *kvm, struct serial8250_device *dev)
> return;
> }
>
> - if (!term_readable(CONSOLE_8250))
> + if (!term_readable(CONSOLE_8250, dev->id))
> return;
>
> - c = term_getc(CONSOLE_8250);
> + c = term_getc(CONSOLE_8250, dev->id);
>
> if (c < 0)
> return;
> @@ -123,30 +128,31 @@ static void serial8250__receive(struct kvm *kvm, struct serial8250_device *dev)
> dev->lsr |= UART_LSR_DR;
> }
>
> -/*
> - * Interrupts are injected for ttyS0 only.
> - */
> void serial8250__inject_interrupt(struct kvm *kvm)
> {
> - struct serial8250_device *dev = &devices[0];
> + int i;
>
> - mutex_lock(&dev->mutex);
> + for (i = 0; i < 4; i++) {
> + struct serial8250_device *dev = &devices[i];
>
> - serial8250__receive(kvm, dev);
> + mutex_lock(&dev->mutex);
>
> - if (dev->ier & UART_IER_RDI && dev->lsr & UART_LSR_DR)
> - dev->iir = UART_IIR_RDI;
> - else if (dev->ier & UART_IER_THRI)
> - dev->iir = UART_IIR_THRI;
> - else
> - dev->iir = UART_IIR_NO_INT;
> + serial8250__receive(kvm, dev);
>
> - if (dev->iir != UART_IIR_NO_INT) {
> - kvm__irq_line(kvm, dev->irq, 0);
> - kvm__irq_line(kvm, dev->irq, 1);
> - }
> + if (dev->ier & UART_IER_RDI && dev->lsr & UART_LSR_DR)
> + dev->iir = UART_IIR_RDI;
> + else if (dev->ier & UART_IER_THRI)
> + dev->iir = UART_IIR_THRI;
> + else
> + dev->iir = UART_IIR_NO_INT;
>
> - mutex_unlock(&dev->mutex);
> + if (dev->iir != UART_IIR_NO_INT) {
> + kvm__irq_line(kvm, dev->irq, 0);
> + kvm__irq_line(kvm, dev->irq, 1);
> + }
> +
> + mutex_unlock(&dev->mutex);
> + }
> }
>
> void serial8250__inject_sysrq(struct kvm *kvm)
> @@ -217,7 +223,7 @@ static bool serial8250_out(struct ioport *ioport, struct kvm *kvm, u16 port, voi
> char *addr = data;
>
> if (!(dev->mcr & UART_MCR_LOOP))
> - term_putc(CONSOLE_8250, addr, size);
> + term_putc(CONSOLE_8250, addr, size, dev->id);
>
> dev->iir = UART_IIR_NO_INT;
> break;
> diff --git a/tools/kvm/include/kvm/term.h b/tools/kvm/include/kvm/term.h
> index 4d580e1..37ec731 100644
> --- a/tools/kvm/include/kvm/term.h
> +++ b/tools/kvm/include/kvm/term.h
> @@ -6,12 +6,13 @@
> #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);
> +int term_putc_iov(int who, struct iovec *iov, int iovcnt, int term);
> +int term_getc_iov(int who, struct iovec *iov, int iovcnt, int term);
> +int term_putc(int who, char *addr, int cnt, int term);
> +int term_getc(int who, int term);
>
> -bool term_readable(int who);
> +bool term_readable(int who, int term);
> +void term_set_tty(int term);
> void term_init(void);
>
> #endif /* KVM__TERM_H */
> diff --git a/tools/kvm/term.c b/tools/kvm/term.c
> index fa4382d..45e8bab 100644
> --- a/tools/kvm/term.c
> +++ b/tools/kvm/term.c
> @@ -5,6 +5,8 @@
> #include <unistd.h>
> #include <sys/uio.h>
> #include <signal.h>
> +#include <pty.h>
> +#include <utmp.h>
>
> #include "kvm/read-write.h"
> #include "kvm/term.h"
> @@ -20,14 +22,16 @@ bool term_got_escape = false;
>
> int active_console;
>
> -int term_getc(int who)
> +int term_fds[4][2];
> +
> +int term_getc(int who, int term)
> {
> int c;
>
> if (who != active_console)
> return -1;
>
> - if (read_in_full(STDIN_FILENO, &c, 1) < 0)
> + if (read_in_full(term_fds[term][0], &c, 1) < 0)
We need a Macro like:
#define TERM_FD_IN 0
#define TERM_FD_OUT 1
> return -1;
>
> c &= 0xff;
> @@ -48,26 +52,27 @@ int term_getc(int who)
> return c;
> }
>
> -int term_putc(int who, char *addr, int cnt)
> +int term_putc(int who, char *addr, int cnt, int term)
> {
> + int ret;
> +
> if (who != active_console)
> return -1;
>
> while (cnt--)
> - fprintf(stdout, "%c", *addr++);
> + ret = write(term_fds[term][1], addr++, 1);
Here and some other places too.
And I am seeing:
term.c: In function ‘term_putc’:
term.c:57:6: error: variable ‘ret’ set but not used
[-Werror=unused-but-set-variable]
cc1: all warnings being treated as errors
> - fflush(stdout);
> return cnt;
> }
>
> -int term_getc_iov(int who, struct iovec *iov, int iovcnt)
> +int term_getc_iov(int who, struct iovec *iov, int iovcnt, int term)
> {
> int c;
>
> if (who != active_console)
> return 0;
>
> - c = term_getc(who);
> + c = term_getc(who, term);
>
> if (c < 0)
> return 0;
> @@ -77,18 +82,18 @@ int term_getc_iov(int who, struct iovec *iov, int iovcnt)
> return sizeof(char);
> }
>
> -int term_putc_iov(int who, struct iovec *iov, int iovcnt)
> +int term_putc_iov(int who, struct iovec *iov, int iovcnt, int term)
> {
> if (who != active_console)
> return 0;
>
> - return writev(STDOUT_FILENO, iov, iovcnt);
> + return writev(term_fds[term][1], iov, iovcnt);
> }
>
> -bool term_readable(int who)
> +bool term_readable(int who, int term)
> {
> struct pollfd pollfd = (struct pollfd) {
> - .fd = STDIN_FILENO,
> + .fd = term_fds[term][0],
> .events = POLLIN,
> .revents = 0,
> };
> @@ -101,7 +106,10 @@ bool term_readable(int who)
>
> static void term_cleanup(void)
> {
> - tcsetattr(STDIN_FILENO, TCSANOW, &orig_term);
> + int i;
> +
> + for (i = 0; i < 4; i++)
> + tcsetattr(term_fds[i][0], TCSANOW, &orig_term);
> }
>
> static void term_sig_cleanup(int sig)
> @@ -111,9 +119,31 @@ static void term_sig_cleanup(int sig)
> raise(sig);
> }
>
> +void term_set_tty(int term)
> +{
> + struct termios orig_term;
> + int master, slave;
> + char new_pty[PATH_MAX];
> +
> + if (tcgetattr(STDIN_FILENO, &orig_term) < 0)
> + die("unable to save initial standard input settings");
> +
> + orig_term.c_lflag &= ~(ICANON | ECHO | ISIG);
> +
> + if (openpty(&master, &slave, new_pty, &orig_term, NULL) < 0)
> + return;
> +
> + close(slave);
> +
> + pr_info("Assigned terminal %d to pty %s\n", term, new_pty);
> +
> + term_fds[term][0] = term_fds[term][1] = master;
> +}
> +
> void term_init(void)
> {
> struct termios term;
> + int i;
>
> if (tcgetattr(STDIN_FILENO, &orig_term) < 0)
> die("unable to save initial standard input settings");
> @@ -122,6 +152,12 @@ void term_init(void)
> term.c_lflag &= ~(ICANON | ECHO | ISIG);
> tcsetattr(STDIN_FILENO, TCSANOW, &term);
>
> + for (i = 0; i < 4; i++)
> + if (term_fds[i][0] == 0) {
> + term_fds[i][0] = STDIN_FILENO;
> + term_fds[i][1] = STDOUT_FILENO;
> + }
> +
> signal(SIGTERM, term_sig_cleanup);
> atexit(term_cleanup);
> }
> diff --git a/tools/kvm/virtio/console.c b/tools/kvm/virtio/console.c
> index c0ccd6c..b880162 100644
> --- a/tools/kvm/virtio/console.c
> +++ b/tools/kvm/virtio/console.c
> @@ -67,9 +67,9 @@ static void virtio_console__inject_interrupt_callback(struct kvm *kvm, void *par
>
> vq = param;
>
> - if (term_readable(CONSOLE_VIRTIO) && virt_queue__available(vq)) {
> + if (term_readable(CONSOLE_VIRTIO, 0) && virt_queue__available(vq)) {
> head = virt_queue__get_iov(vq, iov, &out, &in, kvm);
> - len = term_getc_iov(CONSOLE_VIRTIO, iov, in);
> + len = term_getc_iov(CONSOLE_VIRTIO, iov, in, 0);
> virt_queue__set_used_elem(vq, head, len);
> virtio_pci__signal_vq(kvm, &cdev.vpci, vq - cdev.vqs);
> }
> @@ -100,7 +100,7 @@ static void virtio_console_handle_callback(struct kvm *kvm, void *param)
>
> while (virt_queue__available(vq)) {
> head = virt_queue__get_iov(vq, iov, &out, &in, kvm);
> - len = term_putc_iov(CONSOLE_VIRTIO, iov, out);
> + len = term_putc_iov(CONSOLE_VIRTIO, iov, out, 0);
> virt_queue__set_used_elem(vq, head, len);
> }
>
--
Asias He
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