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-rw-r--r--drivers/char/hvc_lguest.c177
1 files changed, 0 insertions, 177 deletions
diff --git a/drivers/char/hvc_lguest.c b/drivers/char/hvc_lguest.c
deleted file mode 100644
index efccb2155830..000000000000
--- a/drivers/char/hvc_lguest.c
+++ /dev/null
@@ -1,177 +0,0 @@
-/*D:300
- * The Guest console driver
- *
- * This is a trivial console driver: we use lguest's DMA mechanism to send
- * bytes out, and register a DMA buffer to receive bytes in. It is assumed to
- * be present and available from the very beginning of boot.
- *
- * Writing console drivers is one of the few remaining Dark Arts in Linux.
- * Fortunately for us, the path of virtual consoles has been well-trodden by
- * the PowerPC folks, who wrote "hvc_console.c" to generically support any
- * virtual console. We use that infrastructure which only requires us to write
- * the basic put_chars and get_chars functions and call the right register
- * functions.
- :*/
-
-/*M:002 The console can be flooded: while the Guest is processing input the
- * Host can send more. Buffering in the Host could alleviate this, but it is a
- * difficult problem in general. :*/
-/* 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 <asm/paravirt.h>
-#include "hvc_console.h"
-
-/*D:340 This is our single console input buffer, with associated "struct
- * lguest_dma" referring to it. Note the 0-terminated length array, and the
- * use of physical address for the buffer itself. */
-static char inbuf[256];
-static struct lguest_dma cons_input = { .used_len = 0,
- .addr[0] = __pa(inbuf),
- .len[0] = sizeof(inbuf),
- .len[1] = 0 };
-
-/*D:310 The put_chars() callback is pretty straightforward.
- *
- * First we put the pointer and length in a "struct lguest_dma": we only have
- * one pointer, so we set the second length to 0. Then we use SEND_DMA to send
- * the data to (Host) buffers attached to the console key. Usually a device's
- * key is a physical address within the device's memory, but because the
- * console device doesn't have any associated physical memory, we use the
- * LGUEST_CONSOLE_DMA_KEY constant (aka 0). */
-static int put_chars(u32 vtermno, const char *buf, int count)
-{
- struct lguest_dma dma;
-
- /* FIXME: DMA buffers in a "struct lguest_dma" are not allowed
- * to go over page boundaries. This never seems to happen,
- * but if it did we'd need to fix this code. */
- dma.len[0] = count;
- dma.len[1] = 0;
- dma.addr[0] = __pa(buf);
-
- lguest_send_dma(LGUEST_CONSOLE_DMA_KEY, &dma);
- /* We're expected to return the amount of data we wrote: all of it. */
- return count;
-}
-
-/*D:350 get_chars() is the callback from the hvc_console infrastructure when
- * an interrupt is received.
- *
- * Firstly we see if our buffer has been filled: if not, we return. The rest
- * of the code deals with the fact that the hvc_console() infrastructure only
- * asks us for 16 bytes at a time. We keep a "cons_offset" variable for
- * partially-read buffers. */
-static int get_chars(u32 vtermno, char *buf, int count)
-{
- static int cons_offset;
-
- /* Nothing left to see here... */
- if (!cons_input.used_len)
- return 0;
-
- /* You want more than we have to give? Well, try wanting less! */
- if (cons_input.used_len - cons_offset < count)
- count = cons_input.used_len - cons_offset;
-
- /* Copy across to their buffer and increment offset. */
- memcpy(buf, inbuf + cons_offset, count);
- cons_offset += count;
-
- /* Finished? Zero offset, and reset cons_input so Host will use it
- * again. */
- if (cons_offset == cons_input.used_len) {
- cons_offset = 0;
- cons_input.used_len = 0;
- }
- return count;
-}
-/*:*/
-
-static struct hv_ops lguest_cons = {
- .get_chars = get_chars,
- .put_chars = put_chars,
-};
-
-/*D:320 Console drivers are initialized very early so boot messages can go
- * out. At this stage, the console is output-only. Our driver checks we're a
- * Guest, and if so hands hvc_instantiate() the console number (0), priority
- * (0), and the struct hv_ops containing the put_chars() function. */
-static int __init cons_init(void)
-{
- if (strcmp(pv_info.name, "lguest") != 0)
- return 0;
-
- return hvc_instantiate(0, 0, &lguest_cons);
-}
-console_initcall(cons_init);
-
-/*D:370 To set up and manage our virtual console, we call hvc_alloc() and
- * stash the result in the private pointer of the "struct lguest_device".
- * Since we never remove the console device we never need this pointer again,
- * but using ->private is considered good form, and you never know who's going
- * to copy your driver.
- *
- * Once the console is set up, we bind our input buffer ready for input. */
-static int lguestcons_probe(struct lguest_device *lgdev)
-{
- int err;
-
- /* The first argument of hvc_alloc() is the virtual console number, so
- * we use zero. The second argument is the interrupt number.
- *
- * The third argument is a "struct hv_ops" containing the put_chars()
- * and get_chars() pointers. The final argument is the output buffer
- * size: we use 256 and expect the Host to have room for us to send
- * that much. */
- lgdev->private = hvc_alloc(0, lgdev_irq(lgdev), &lguest_cons, 256);
- if (IS_ERR(lgdev->private))
- return PTR_ERR(lgdev->private);
-
- /* We bind a single DMA buffer at key LGUEST_CONSOLE_DMA_KEY.
- * "cons_input" is that statically-initialized global DMA buffer we saw
- * above, and we also give the interrupt we want. */
- err = lguest_bind_dma(LGUEST_CONSOLE_DMA_KEY, &cons_input, 1,
- lgdev_irq(lgdev));
- if (err)
- printk("lguest console: failed to bind buffer.\n");
- return err;
-}
-/* Note the use of lgdev_irq() for the interrupt number. We tell hvc_alloc()
- * to expect input when this interrupt is triggered, and then tell
- * lguest_bind_dma() that is the interrupt to send us when input comes in. */
-
-/*D:360 From now on the console driver follows standard Guest driver form:
- * register_lguest_driver() registers the device type and probe function, and
- * the probe function sets up the device.
- *
- * The standard "struct lguest_driver": */
-static struct lguest_driver lguestcons_drv = {
- .name = "lguestcons",
- .owner = THIS_MODULE,
- .device_type = LGUEST_DEVICE_T_CONSOLE,
- .probe = lguestcons_probe,
-};
-
-/* The standard init function */
-static int __init hvc_lguest_init(void)
-{
- return register_lguest_driver(&lguestcons_drv);
-}
-module_init(hvc_lguest_init);