[libvirt] [PATCH v2] libxl: support serial list

[Jim Fehlig]

On 08/03/2016 07:25 PM, Bob Liu wrote:
> Add support for multi serial devices, after this patch virsh can be used to
> connect different serial devices of running domains. E.g.
> vish # console <xxx> --devname serial<xxx>

Thanks for the patch, and sorry for the delayed response.

>
> Note:
> This depends on a xen/libxl bug fix to have libxl_console_get_tty(...) correctly
> returning the tty path (as opposed to always returning the first one).
> [0] https://lists.xen.org/archives/html/xen-devel/2016-08/msg00438.html
>
> Signed-off-by: Bob Liu <bob.liu at oracle.com>
> ---
> v2: Add #ifdef LIBXL_HAVE_BUILDINFO_SERIAL_LIST
> ---
>  src/libxl/libxl_conf.c   | 24 +++++++++++++++++++++---
>  src/libxl/libxl_domain.c | 23 +++++++++++++++++++++++
>  src/libxl/libxl_driver.c | 17 +++++++++--------
>  3 files changed, 53 insertions(+), 11 deletions(-)
>
> diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c
> index 146e08a..26c704d 100644
> --- a/src/libxl/libxl_conf.c
> +++ b/src/libxl/libxl_conf.c
> @@ -431,14 +431,32 @@ libxlMakeDomBuildInfo(virDomainDefPtr def,
>          }
>  
>          if (def->nserials) {
> -            if (def->nserials > 1) {
> +            if (def->nserials == 1) {
> +                if (libxlMakeChrdevStr(def->serials[0], &b_info->u.hvm.serial) <
> +                    0)
> +                    return -1;
> +            } else {
> +#ifdef LIBXL_HAVE_BUILDINFO_SERIAL_LIST
> +                if (VIR_ALLOC_N(b_info->u.hvm.serial_list, def->nserials + 1) <
> +                    0)

Your mailer has mangled some lines...

> +                    return -1;
> +
> +                for (i = 0; i < def->nserials; i++) {
> +                    if (libxlMakeChrdevStr(def->serials[i],
> +                                           &b_info->u.hvm.serial_list[i]) < 0)
> +                    {
> +                        libxl_string_list_dispose(&b_info->u.hvm.serial_list);
> +                        return -1;
> +                    }
> +                }
> +                b_info->u.hvm.serial_list[i] = NULL;
> +#else
>                  virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
>                                 "%s",
>                                 _("Only one serial device is supported by libxl"));
>                  return -1;
> +#endif
>              }
> -            if (libxlMakeChrdevStr(def->serials[0], &b_info->u.hvm.serial) < 0)
> -                return -1;
>          }
>  
>          if (def->nparallels) {
> diff --git a/src/libxl/libxl_domain.c b/src/libxl/libxl_domain.c
> index 0e26b91..5d8c9c1 100644
> --- a/src/libxl/libxl_domain.c
> +++ b/src/libxl/libxl_domain.c
> @@ -989,6 +989,29 @@ libxlConsoleCallback(libxl_ctx *ctx, libxl_event *ev, void *for_callback)
>              VIR_FREE(console);
>          }
>      }
> +    for (i = 0; i < vm->def->nserials; i++) {
> +        virDomainChrDefPtr chr = vm->def->serials[i];
> +        char *console = NULL;
> +        int ret;

These variable declarations (along with their counterparts in the previous loop)
can be moved to the beginning of the function since they are now used in both loops.

> +
> +        ignore_value(virAsprintf(&chr->info.alias, "serial%zd", i));
> +        if (chr->source.type == VIR_DOMAIN_CHR_TYPE_PTY) {
> +            if (chr->source.data.file.path)
> +                continue;
> +            ret = libxl_console_get_tty(ctx, ev->domid,
> +                                        chr->target.port,
> +                                        LIBXL_CONSOLE_TYPE_SERIAL,
> +                                        &console);
> +            if (!ret) {
> +                VIR_FREE(chr->source.data.file.path);
> +                if (console && console[0] != '\0') {
> +                    ignore_value(VIR_STRDUP(chr->source.data.file.path,
> +                                            console));
> +                }
> +            }
> +            VIR_FREE(console);
> +        }
> +    }
>      virObjectUnlock(vm);
>      libxl_event_free(ctx, ev);
>  }
> diff --git a/src/libxl/libxl_driver.c b/src/libxl/libxl_driver.c
> index f153f69..a34eb02 100644
> --- a/src/libxl/libxl_driver.c
> +++ b/src/libxl/libxl_driver.c
> @@ -4450,13 +4450,6 @@ libxlDomainOpenConsole(virDomainPtr dom,
>  
>      virCheckFlags(VIR_DOMAIN_CONSOLE_FORCE, -1);
>  
> -    if (dev_name) {
> -        /* XXX support device aliases in future */
> -        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
> -                       _("Named device aliases are not supported"));
> -        goto cleanup;
> -    }
> -
>      if (!(vm = libxlDomObjFromDomain(dom)))
>          goto cleanup;
>  
> @@ -4472,8 +4465,16 @@ libxlDomainOpenConsole(virDomainPtr dom,
>      }
>  
>      priv = vm->privateData;
> +    if (dev_name) {
> +        size_t i;
>  
> -    if (vm->def->nconsoles) {
> +        for (i = 0; !chr && i < vm->def->nserials; i++) {
> +            if (STREQ(dev_name, vm->def->serials[i]->info.alias)) {
> +                chr = vm->def->serials[i];
> +                break;
> +            }
> +        }
> +    } else if (vm->def->nconsoles) {
>          chr = vm->def->consoles[0];
>          if (chr->targetType == VIR_DOMAIN_CHR_CONSOLE_TARGET_TYPE_SERIAL)
>              chr = vm->def->serials[0];

Along with fixing these nits, you'll have to add support for converting domXML
<-> xl.cfg that contain multiple serial devices. IIRC, xm.cfg did not support
specifying more than one serial device, so the serial device parsing/formatting
logic in src/xenconfig/xen_common.c may have to be moved to
src/xenconfig/xen_{xl,xm}.c. Sadly, such changes often require changing many of
the test data files under tests/{xl,xm}configdata/, sorry :-(.

Also, please add a test for domXML <-> xl.cfg conversions containing multiple
serial devices. Thanks!

Regards,
Jim