From: Sergiy Kibrik <sergiy.kib...@globallogic.com>
Committer: Nadav Har'El <n...@scylladb.com>
Branch: master

xenconsole: shared ring suport

Complete driver to properly work with xl console utility, i.e. full read/write access. Driver is extended to work with shared structure (ring) and event channel.

Signed-off-by: Sergiy Kibrik <sergiy.kib...@globallogic.com>
Message-Id: <1490018156-16491-1-git-send-email-sergiy.kib...@globallogic.com>

---
diff --git a/drivers/xenconsole.cc b/drivers/xenconsole.cc
--- a/drivers/xenconsole.cc
+++ b/drivers/xenconsole.cc
@@ -5,32 +5,105 @@
  * BSD license as described in the LICENSE file in the top-level directory.
  */

+#define XENHVM //FIXME hack to reveal hvm_get_parameter()
 #include <bsd/porting/netport.h> /* __dead2 defined here */
+#include <bsd/porting/bus.h>
+#include <machine/xen/xen-os.h>
 #include <xen/hypervisor.h>
-
+#include <xen/interface/hvm/params.h>
+#include <xen/interface/io/console.h>
+#include <xen/xen_intr.h>
+#include <xen/evtchn.h>
+#include <osv/mmio.hh>
 #include "xenconsole.hh"

 namespace console {

+XEN_Console::
+XEN_Console::XEN_Console()
+    : _interface(0)
+     , _evtchn(-1)
+     , _irq(0)
+     , _pfn(0)
+{}
+
+void XEN_Console::handle_intr()
+{
+    _thread->wake();
+}
+
 void XEN_Console::write(const char *str, size_t len) {
-       HYPERVISOR_console_write(str, len);
+    assert(len > 0);
+    if (!_interface) {
+        HYPERVISOR_console_write(str, len);
+        return;
+    }
+
+    /* str might be larger then ring, so write it by chunks in this case */
+    XENCONS_RING_IDX prod = _interface->out_prod;
+    constexpr auto ringsize = sizeof(_interface->out) - 1;
+    while (true) {
+        XENCONS_RING_IDX cons = _interface->out_cons;
+        auto delta = prod - cons;
+
+        if (unlikely(delta > ringsize)) {
+ prod = cons; /* ring is corrupted, reset is the best we can do */
+            delta = 0;
+        }
+
+        size_t c = 0;
+        for (; c < std::min(ringsize - delta, len); c++)
+ _interface->out[MASK_XENCONS_IDX(prod++, _interface->out)] = *str++;
+
+        _interface->out_prod = prod;
+        wmb();
+
+        if (likely(c == len))
+            break; /* flush() will do evtchn notification */
+
+        len -= ringsize - delta;
+        notify_remote_via_evtchn(_evtchn);
+
+        while (_interface->out_cons != _interface->out_prod)
+            cpu_relax(); /* can't sleep here */
+    }
 }

 void XEN_Console::dev_start()
 {
+    _pfn = hvm_get_parameter(HVM_PARAM_CONSOLE_PFN);
+    _evtchn = hvm_get_parameter(HVM_PARAM_CONSOLE_EVTCHN);
+
+    if (!_pfn || !_evtchn)
+        throw std::runtime_error("fail to get console params");
+
+     if (bind_caller_port_to_irqhandler(_evtchn, "xenconsole",
+            XEN_Console::console_intr,
+            static_cast<void*>(this),
+            INTR_TYPE_MISC, &_irq) != 0)
+        throw std::runtime_error("fail to bind evtchn");
+
+ _interface = (xencons_interface*)mmio_map(_pfn << PAGE_SHIFT, PAGE_SIZE);
 }

 void XEN_Console::flush()
 {
+    notify_remote_via_evtchn(_evtchn);
 }

 bool XEN_Console::input_ready()
 {
-       return false; /*TODO: support input */
+    return _interface->in_cons != _interface->in_prod;
 }

 char XEN_Console::readch() {
-    return '\0'; /*TODO: support input */
+    XENCONS_RING_IDX cons;
+    char c;
+    assert(_interface);
+    cons = _interface->in_cons;
+    c = _interface->in[MASK_XENCONS_IDX(cons, _interface->in)];
+    mb();
+    _interface->in_cons = cons + 1;
+    return c;
 }
-
 }
diff --git a/drivers/xenconsole.hh b/drivers/xenconsole.hh
--- a/drivers/xenconsole.hh
+++ b/drivers/xenconsole.hh
@@ -9,13 +9,14 @@
 #define XEN_CONSOLE_HH

 #include "console-driver.hh"
-#include "exceptions.hh"
-#include <osv/interrupt.hh>
+#include <xen/interface/xen.h>
+#include <xen/interface/grant_table.h>

 namespace console {

 class XEN_Console : public console_driver {
 public:
+    XEN_Console();
     virtual void write(const char *str, size_t len);
     virtual void flush();
     virtual bool input_ready();
@@ -24,6 +25,15 @@ public:
 private:
     virtual void dev_start();
     virtual const char *thread_name() { return "xen-input"; }
+    void handle_intr();
+    static void console_intr(void *arg) {
+        static_cast<XEN_Console*>(arg)->handle_intr();
+    }
+
+    struct xencons_interface *_interface;
+    int _evtchn;
+    unsigned int _irq;
+    unsigned long _pfn;
 };

 }

--
You received this message because you are subscribed to the Google Groups "OSv 
Development" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to osv-dev+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to