From 6b9b732d0e396a3f1a95977162a8624aafce38a1 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Mon, 26 May 2008 23:31:25 +0100 Subject: [PATCH] xen-console: add save/restore Add code to: 1. Deal with the console page being canonicalized. During save, the console's mfn in the start_info structure is canonicalized to a pfn. In order to deal with that, we always use a copy of the pfn and indirect off that all the time. However, we fall back to using the mfn if the pfn hasn't been initialized yet. 2. Restore the console event channel, and rebind it to the existing irq. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Thomas Gleixner --- drivers/char/hvc_xen.c | 25 +++++++++++++++++++++---- include/xen/hvc-console.h | 2 ++ 2 files changed, 23 insertions(+), 4 deletions(-) diff --git a/drivers/char/hvc_xen.c b/drivers/char/hvc_xen.c index d5fe0a8952f..db2ae421627 100644 --- a/drivers/char/hvc_xen.c +++ b/drivers/char/hvc_xen.c @@ -39,9 +39,14 @@ static int xencons_irq; /* ------------------------------------------------------------------ */ +static unsigned long console_pfn = ~0ul; + static inline struct xencons_interface *xencons_interface(void) { - return mfn_to_virt(xen_start_info->console.domU.mfn); + if (console_pfn == ~0ul) + return mfn_to_virt(xen_start_info->console.domU.mfn); + else + return __va(console_pfn << PAGE_SHIFT); } static inline void notify_daemon(void) @@ -101,20 +106,32 @@ static int __init xen_init(void) { struct hvc_struct *hp; - if (!is_running_on_xen()) - return 0; + if (!is_running_on_xen() || + is_initial_xendomain() || + !xen_start_info->console.domU.evtchn) + return -ENODEV; xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn); if (xencons_irq < 0) - xencons_irq = 0 /* NO_IRQ */; + xencons_irq = 0; /* NO_IRQ */ + hp = hvc_alloc(HVC_COOKIE, xencons_irq, &hvc_ops, 256); if (IS_ERR(hp)) return PTR_ERR(hp); hvc = hp; + + console_pfn = mfn_to_pfn(xen_start_info->console.domU.mfn); + return 0; } +void xen_console_resume(void) +{ + if (xencons_irq) + rebind_evtchn_irq(xen_start_info->console.domU.evtchn, xencons_irq); +} + static void __exit xen_fini(void) { if (hvc) diff --git a/include/xen/hvc-console.h b/include/xen/hvc-console.h index efc3237ab99..fd5483a059b 100644 --- a/include/xen/hvc-console.h +++ b/include/xen/hvc-console.h @@ -3,6 +3,8 @@ extern struct console xenboot_console; +void xen_console_resume(void); + void xen_raw_console_write(const char *str); void xen_raw_printk(const char *fmt, ...); -- 2.41.0