3f8c4d3f82
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> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
103 lines
2.6 KiB
C
103 lines
2.6 KiB
C
/* Simple console for lguest.
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*
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* Copyright (C) 2006 Rusty Russell, IBM Corporation
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/err.h>
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#include <linux/init.h>
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#include <linux/lguest_bus.h>
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#include "hvc_console.h"
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static char inbuf[256];
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static struct lguest_dma cons_input = { .used_len = 0,
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.addr[0] = __pa(inbuf),
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.len[0] = sizeof(inbuf),
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.len[1] = 0 };
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static int put_chars(u32 vtermno, const char *buf, int count)
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{
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struct lguest_dma dma;
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/* FIXME: what if it's over a page boundary? */
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dma.len[0] = count;
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dma.len[1] = 0;
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dma.addr[0] = __pa(buf);
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lguest_send_dma(LGUEST_CONSOLE_DMA_KEY, &dma);
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return count;
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}
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static int get_chars(u32 vtermno, char *buf, int count)
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{
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static int cons_offset;
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if (!cons_input.used_len)
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return 0;
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if (cons_input.used_len - cons_offset < count)
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count = cons_input.used_len - cons_offset;
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memcpy(buf, inbuf + cons_offset, count);
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cons_offset += count;
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if (cons_offset == cons_input.used_len) {
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cons_offset = 0;
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cons_input.used_len = 0;
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}
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return count;
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}
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static struct hv_ops lguest_cons = {
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.get_chars = get_chars,
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.put_chars = put_chars,
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};
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static int __init cons_init(void)
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{
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if (strcmp(paravirt_ops.name, "lguest") != 0)
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return 0;
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return hvc_instantiate(0, 0, &lguest_cons);
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}
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console_initcall(cons_init);
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static int lguestcons_probe(struct lguest_device *lgdev)
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{
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int err;
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lgdev->private = hvc_alloc(0, lgdev_irq(lgdev), &lguest_cons, 256);
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if (IS_ERR(lgdev->private))
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return PTR_ERR(lgdev->private);
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err = lguest_bind_dma(LGUEST_CONSOLE_DMA_KEY, &cons_input, 1,
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lgdev_irq(lgdev));
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if (err)
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printk("lguest console: failed to bind buffer.\n");
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return err;
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}
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static struct lguest_driver lguestcons_drv = {
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.name = "lguestcons",
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.owner = THIS_MODULE,
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.device_type = LGUEST_DEVICE_T_CONSOLE,
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.probe = lguestcons_probe,
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};
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static int __init hvc_lguest_init(void)
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{
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return register_lguest_driver(&lguestcons_drv);
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}
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module_init(hvc_lguest_init);
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