From: Rusty Russell <rusty@rustcorp.com.au>
A simple console driver for lguest.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
drivers/char/Makefile | 1
drivers/char/hvc_lguest.c | 99 ++++++++++++++++++++++++++++++++++++
2 files changed, 100 insertions(+)
diff -puN drivers/char/Makefile~lguest-the-console-driver drivers/char/Makefile
--- a/drivers/char/Makefile~lguest-the-console-driver
+++ a/drivers/char/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_AMIGA_BUILTIN_SERIAL) += am
obj-$(CONFIG_SX) += sx.o generic_serial.o
obj-$(CONFIG_RIO) += rio/ generic_serial.o
obj-$(CONFIG_HVC_CONSOLE) += hvc_vio.o hvsi.o
+obj-$(CONFIG_LGUEST_GUEST) += hvc_lguest.o
obj-$(CONFIG_HVC_ISERIES) += hvc_iseries.o
obj-$(CONFIG_HVC_RTAS) += hvc_rtas.o
obj-$(CONFIG_HVC_BEAT) += hvc_beat.o
diff -puN /dev/null drivers/char/hvc_lguest.c
--- /dev/null
+++ a/drivers/char/hvc_lguest.c
@@ -0,0 +1,99 @@
+/* Simple console for lguest.
+ *
+ * Copyright (C) 2006 Rusty Russell, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/lguest_bus.h>
+#include "hvc_console.h"
+
+static char inbuf[256];
+static struct lguest_dma cons_input = { .used_len = 0,
+ .addr[0] = __pa(inbuf),
+ .len[0] = sizeof(inbuf),
+ .len[1] = 0 };
+
+static int put_chars(u32 vtermno, const char *buf, int count)
+{
+ struct lguest_dma dma;
+
+ /* FIXME: what if it's over a page boundary? */
+ dma.len[0] = count;
+ dma.len[1] = 0;
+ dma.addr[0] = __pa(buf);
+
+ hcall(LHCALL_SEND_DMA, LGUEST_CONSOLE_DMA_KEY, __pa(&dma), 0);
+ return count;
+}
+
+static int get_chars(u32 vtermno, char *buf, int count)
+{
+ static int cons_offset;
+
+ if (!cons_input.used_len)
+ return 0;
+
+ if (cons_input.used_len - cons_offset < count)
+ count = cons_input.used_len - cons_offset;
+
+ memcpy(buf, inbuf + cons_offset, count);
+ cons_offset += count;
+ if (cons_offset == cons_input.used_len) {
+ cons_offset = 0;
+ cons_input.used_len = 0;
+ }
+ return count;
+}
+
+struct hv_ops lguest_cons = {
+ .get_chars = get_chars,
+ .put_chars = put_chars,
+};
+
+static int __init cons_init(void)
+{
+ if (strcmp(paravirt_ops.name, "lguest") != 0)
+ return 0;
+
+ return hvc_instantiate(0, 0, &lguest_cons);
+}
+console_initcall(cons_init);
+
+static int lguestcons_probe(struct lguest_device *lgdev)
+{
+ lgdev->private = hvc_alloc(0, lgdev->index+1, &lguest_cons, 256);
+ if (IS_ERR(lgdev->private))
+ return PTR_ERR(lgdev->private);
+
+ if (!hcall(LHCALL_BIND_DMA, LGUEST_CONSOLE_DMA_KEY, __pa(&cons_input),
+ (1<<8) + lgdev->index+1))
+ printk("lguest console: failed to bind buffer.\n");
+ return 0;
+}
+
+static struct lguest_driver lguestcons_drv = {
+ .name = "lguestcons",
+ .owner = THIS_MODULE,
+ .device_type = LGUEST_DEVICE_T_CONSOLE,
+ .probe = lguestcons_probe,
+};
+
+static int __init hvc_lguest_init(void)
+{
+ return register_lguest_driver(&lguestcons_drv);
+}
+module_init(hvc_lguest_init);
_
