From: Eric Van Hensbergen <[email protected]>
This was a quick modification I did of lguest to be able to support multiple
HVC channels for some experiements I was doing. I'm not sure if this is more
generally useful, so I'm posting it to the list in case someone else has a
need for it.
Signed-off-by: Eric Van Hensbergen <[email protected]>
---
Documentation/lguest/lguest.c | 161 ++++++++++++++++++++++++-----------------
drivers/char/hvc_lguest.c | 57 +++++++++------
2 files changed, 129 insertions(+), 89 deletions(-)
diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c
index f791840..c6a3e4d 100644
--- a/Documentation/lguest/lguest.c
+++ b/Documentation/lguest/lguest.c
@@ -690,12 +690,14 @@ static void restore_term(void)
}
/* We associate some data with the console for our exit hack. */
-struct console_abort
+struct console_priv
{
+ /* which console we are */
+ int index;
/* How many times have they hit ^C? */
- int count;
+ int a_count;
/* When did they start? */
- struct timeval start;
+ struct timeval a_start;
};
/* This is the routine which handles console input (ie. stdin). */
@@ -705,11 +707,12 @@ static bool handle_console_input(int fd, struct device *dev)
int len;
unsigned int num;
struct iovec iov[LGUEST_MAX_DMA_SECTIONS];
- struct console_abort *abort = dev->priv;
+ struct console_priv *cons = dev->priv;
/* First we get the console buffer from the Guest. The key is dev->mem
- * which was set to 0 in setup_console(). */
- lenp = get_dma_buffer(fd, dev->mem, iov, &num, &irq);
+ * plus the console index adjusted to be a multiple of 4 because lguest
+ * wants keys to be a multiple of 4 */
+ lenp = get_dma_buffer(fd, dev->mem+(cons->index*4), iov, &num, &irq);
if (!lenp) {
/* If it's not ready for input, warn and set up to discard. */
warn("console: no dma buffer!");
@@ -734,39 +737,44 @@ static bool handle_console_input(int fd, struct device *dev)
trigger_irq(fd, irq);
}
- /* Three ^C within one second? Exit.
- *
- * This is such a hack, but works surprisingly well. Each ^C has to be
- * in a buffer by itself, so they can't be too fast. But we check that
- * we get three within about a second, so they can't be too slow. */
- if (len == 1 && ((char *)iov[0].iov_base)[0] == 3) {
- if (!abort->count++)
- gettimeofday(&abort->start, NULL);
- else if (abort->count == 3) {
- struct timeval now;
- gettimeofday(&now, NULL);
- if (now.tv_sec <= abort->start.tv_sec+1) {
- u32 args[] = { LHREQ_BREAK, 0 };
- /* Close the fd so Waker will know it has to
- * exit. */
- close(waker_fd);
- /* Just in case waker is blocked in BREAK, send
- * unbreak now. */
- write(fd, args, sizeof(args));
- exit(2);
+ /* Only do interrupt hack and restore_term() on initial console */
+ if (cons->index == 0) {
+ /* Three ^C within one second? Exit.
+ *
+ * This is such a hack, but works surprisingly well. Each ^C
+ * has to be in a buffer by itself, so they can't be too fast.
+ * But we check that we get three within about a second, so
+ * they can't be too slow. */
+ if (len == 1 && ((char *)iov[0].iov_base)[0] == 3) {
+ if (!cons->a_count++)
+ gettimeofday(&cons->a_start, NULL);
+ else if (cons->a_count == 3) {
+ struct timeval now;
+ gettimeofday(&now, NULL);
+ if (now.tv_sec <= cons->a_start.tv_sec+1) {
+ u32 args[] = { LHREQ_BREAK, 0 };
+ /* Close the fd so Waker will know it
+ * has to exit. */
+ close(waker_fd);
+ /* Just in case waker is blocked in
+ * BREAK, send unbreak now. */
+ write(fd, args, sizeof(args));
+ exit(2);
+ }
+ cons->a_count = 0;
}
- abort->count = 0;
+ } else
+ /* Any other key resets the abort counter. */
+ cons->a_count = 0;
+
+ /* Now, if we didn't read anything, put the input terminal
+ * back and return failure (meaning, don't call us again). */
+ if (!len) {
+ restore_term();
+ return false;
}
- } else
- /* Any other key resets the abort counter. */
- abort->count = 0;
-
- /* Now, if we didn't read anything, put the input terminal back and
- * return failure (meaning, don't call us again). */
- if (!len) {
- restore_term();
- return false;
}
+
/* Everything went OK! */
return true;
}
@@ -777,7 +785,7 @@ static u32 handle_console_output(int fd, const struct iovec *iov,
{
/* Whatever the Guest sends, write it to standard output. Return the
* number of bytes written. */
- return writev(STDOUT_FILENO, iov, num);
+ return writev(dev->fd, iov, num);
}
/* Guest->Host network output is also pretty easy. */
@@ -1044,34 +1052,56 @@ static struct device *new_device(struct device_list *devices,
return dev;
}
+static u32 str2ip(const char *ipaddr)
+{
+ unsigned int byte[4];
+
+ sscanf(ipaddr, "%u.%u.%u.%u", &byte[0], &byte[1], &byte[2], &byte[3]);
+ return (byte[0] << 24) | (byte[1] << 16) | (byte[2] << 8) | byte[3];
+}
+
/* Our first setup routine is the console. It's a fairly simple device, but
* UNIX tty handling makes it uglier than it could be. */
-static void setup_console(struct device_list *devices)
+static void setup_console(char *arg, struct device_list *devices)
{
struct device *dev;
-
- /* If we can save the initial standard input settings... */
- if (tcgetattr(STDIN_FILENO, &orig_term) == 0) {
- struct termios term = orig_term;
- /* Then we turn off echo, line buffering and ^C etc. We want a
- * raw input stream to the Guest. */
- term.c_lflag &= ~(ISIG|ICANON|ECHO);
- tcsetattr(STDIN_FILENO, TCSANOW, &term);
- /* If we exit gracefully, the original settings will be
- * restored so the user can see what they're typing. */
- atexit(restore_term);
+ int fd;
+ static int hvcs_index;
+ struct console_priv *cons;
+
+ if (arg == NULL) { /* default console - do the tty stuff */
+ /* If we can save the initial standard input settings... */
+ if (tcgetattr(STDIN_FILENO, &orig_term) == 0) {
+ struct termios term = orig_term;
+ /* Then we turn off echo, line buffering and ^C etc.
+ * We want a raw input stream to the Guest. */
+ term.c_lflag &= ~(ISIG|ICANON|ECHO);
+ tcsetattr(STDIN_FILENO, TCSANOW, &term);
+ /* If we exit gracefully, the original settings will be
+ * restored so the user can see what they're typing. */
+ atexit(restore_term);
+ }
+ fd = STDIN_FILENO;
+ } else {
+ /* create or open an exisitng fifo */
+ mkfifo(arg, S_IWUSR | S_IRUSR);
+ fd = open_or_die(arg, O_RDWR);
}
/* We don't currently require any memory for the console, so we ask for
* 0 pages. */
dev = new_device(devices, LGUEST_DEVICE_T_CONSOLE, 0, 0,
- STDIN_FILENO, handle_console_input,
- LGUEST_CONSOLE_DMA_KEY, handle_console_output);
- /* We store the console state in dev->priv, and initialize it. */
- dev->priv = malloc(sizeof(struct console_abort));
- ((struct console_abort *)dev->priv)->count = 0;
- verbose("device %p: console\n",
- (void *)(dev->desc->pfn * getpagesize()));
+ fd, handle_console_input,
+ LGUEST_CONSOLE_DMA_KEY+(hvcs_index*4),
+ handle_console_output);
+ dev->fd = fd;
+ /* We store the console state in dev->priv, and initialize */
+ dev->priv = malloc(sizeof(struct console_priv));
+ cons = dev->priv;
+ cons->a_count = 0;
+ cons->index = hvcs_index++;
+ verbose("device %p: console %d\n",
+ (void *)(dev->desc->pfn * getpagesize()), cons->index);
}
/* Setting up a block file is also fairly straightforward. */
@@ -1184,14 +1214,6 @@ static void setup_net_file(const char *filename,
}
/*:*/
-static u32 str2ip(const char *ipaddr)
-{
- unsigned int byte[4];
-
- sscanf(ipaddr, "%u.%u.%u.%u", &byte[0], &byte[1], &byte[2], &byte[3]);
- return (byte[0] << 24) | (byte[1] << 16) | (byte[2] << 8) | byte[3];
-}
-
/* This code is "adapted" from libbridge: it attaches the Host end of the
* network device to the bridge device specified by the command line.
*
@@ -1369,12 +1391,14 @@ static struct option opts[] = {
{ "tunnet", 1, NULL, 't' },
{ "block", 1, NULL, 'b' },
{ "initrd", 1, NULL, 'i' },
+ { "console", 1, NULL, 'c' },
{ NULL },
};
static void usage(void)
{
errx(1, "Usage: lguest [--verbose] "
"[--sharenet=<filename>|--tunnet=(<ipaddr>|bridge:<bridgename>)\n"
+ "|--console=<fifopath>...\n"
"|--block=<filename>|--initrd=<filename>]...\n"
"<mem-in-mb> vmlinux [args...]");
}
@@ -1431,6 +1455,9 @@ int main(int argc, char *argv[])
}
}
+ /* We always have at least one console device */
+ setup_console(NULL, &device_list);
+
/* The options are fairly straight-forward */
while ((c = getopt_long(argc, argv, "v", opts, NULL)) != EOF) {
switch (c) {
@@ -1446,6 +1473,9 @@ int main(int argc, char *argv[])
case 'b':
setup_block_file(optarg, &device_list);
break;
+ case 'c':
+ setup_console(optarg, &device_list);
+ break;
case 'i':
initrd_name = optarg;
break;
@@ -1459,9 +1489,6 @@ int main(int argc, char *argv[])
if (optind + 2 > argc)
usage();
- /* We always have a console device */
- setup_console(&device_list);
-
/* We start by mapping anonymous pages over all of guest-physical
* memory range. This fills it with 0, and ensures that the Guest
* won't be killed when it tries to access it. */
diff --git a/drivers/char/hvc_lguest.c b/drivers/char/hvc_lguest.c
index 3d6bd0b..b8b026a 100644
--- a/drivers/char/hvc_lguest.c
+++ b/drivers/char/hvc_lguest.c
@@ -38,14 +38,15 @@
#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 };
+#define MAX_LGUEST_CONS 2
+
+/*D:340 Each console instance has an input buffer and associated offset
+associated with it. Uck -- still static, can't we fix this? */
+static struct lguest_console {
+ struct lguest_dma cons_input;
+ int cons_offset;
+ void *inbuf;
+} lguest_con[MAX_LGUEST_CONS];
/*D:310 The put_chars() callback is pretty straightforward.
*
@@ -54,7 +55,8 @@ static struct lguest_dma cons_input = { .used_len = 0,
* 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). */
+ * LGUEST_CONSOLE_DMA_KEY constant (aka 0) plus the console index multiplied
+ * by 4 (because keys must be aligned along 32-bit addresses). */
static int put_chars(u32 vtermno, const char *buf, int count)
{
struct lguest_dma dma;
@@ -66,7 +68,7 @@ static int put_chars(u32 vtermno, const char *buf, int count)
dma.len[1] = 0;
dma.addr[0] = __pa(buf);
- lguest_send_dma(LGUEST_CONSOLE_DMA_KEY, &dma);
+ lguest_send_dma(LGUEST_CONSOLE_DMA_KEY+(vtermno*4), &dma);
/* We're expected to return the amount of data we wrote: all of it. */
return count;
}
@@ -80,26 +82,27 @@ static int put_chars(u32 vtermno, const char *buf, int count)
* partially-read buffers. */
static int get_chars(u32 vtermno, char *buf, int count)
{
- static int cons_offset;
+ struct lguest_console *lgc = &lguest_con[vtermno];
/* Nothing left to see here... */
- if (!cons_input.used_len)
+ if (!lgc->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;
+ if (lgc->cons_input.used_len - lgc->cons_offset < count)
+ count = lgc->cons_input.used_len - lgc->cons_offset;
/* Copy across to their buffer and increment offset. */
- memcpy(buf, inbuf + cons_offset, count);
- cons_offset += count;
+ memcpy(buf, lgc->inbuf + lgc->cons_offset, count);
+ lgc->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;
+ if (lgc->cons_offset == lgc->cons_input.used_len) {
+ lgc->cons_offset = 0;
+ lgc->cons_input.used_len = 0;
}
+
return count;
}
/*:*/
@@ -132,6 +135,14 @@ console_initcall(cons_init);
static int lguestcons_probe(struct lguest_device *lgdev)
{
int err;
+ static int index;
+ struct lguest_console *lgc = &lguest_con[index];
+
+ lgc->inbuf = (void *) get_zeroed_page(GFP_KERNEL);
+ lgc->cons_input.used_len = 0;
+ lgc->cons_input.addr[0] = (unsigned long) __pa(lgc->inbuf);
+ lgc->cons_input.len[0] = PAGE_SIZE;
+ lgc->cons_input.len[1] = 0;
/* The first argument of hvc_alloc() is the virtual console number, so
* we use zero. The second argument is the interrupt number.
@@ -140,17 +151,19 @@ static int lguestcons_probe(struct lguest_device *lgdev)
* 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);
+ lgdev->private = hvc_alloc(index, lgdev_irq(lgdev), &lguest_cons,
+ PAGE_SIZE);
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));
+ err = lguest_bind_dma(LGUEST_CONSOLE_DMA_KEY+(index*4),
+ &lgc->cons_input, 1, lgdev_irq(lgdev));
if (err)
printk("lguest console: failed to bind buffer.\n");
+ index++;
return err;
}
/* Note the use of lgdev_irq() for the interrupt number. We tell hvc_alloc()
--
1.5.0.gddff-dirty
-
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