From: Jeff Dike <jdike@addtoit.com>
This patch adds some errors and warnings where there were none before:
If someone typos "ubd" as "udb", that is caught and a warning is printed
If a ubd file can't be opened, that now results in an error message
If there are more telnet connections to port consoles than there are
consoles, then a message will appear in the telnet session explaining why
there is no login prompt.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/arch/um/drivers/port_kern.c | 23 ++++++++++++++++++++---
25-akpm/arch/um/drivers/ubd_kern.c | 22 +++++++++++++++++++++-
2 files changed, 41 insertions(+), 4 deletions(-)
diff -puN arch/um/drivers/port_kern.c~uml-improve-error-reporting arch/um/drivers/port_kern.c
--- 25/arch/um/drivers/port_kern.c~uml-improve-error-reporting 2005-03-07 22:16:24.000000000 -0800
+++ 25-akpm/arch/um/drivers/port_kern.c 2005-03-07 22:16:24.000000000 -0800
@@ -10,6 +10,7 @@
#include "linux/irq.h"
#include "linux/spinlock.h"
#include "linux/errno.h"
+#include "asm/atomic.h"
#include "asm/semaphore.h"
#include "asm/errno.h"
#include "kern_util.h"
@@ -22,6 +23,7 @@
struct port_list {
struct list_head list;
+ atomic_t wait_count;
int has_connection;
struct semaphore sem;
int port;
@@ -70,6 +72,13 @@ static irqreturn_t pipe_interrupt(int ir
return(IRQ_HANDLED);
}
+#define NO_WAITER_MSG \
+ "****\n" \
+ "There are currently no UML consoles waiting for port connections.\n" \
+ "Either disconnect from one to make it available or activate some more\n" \
+ "by enabling more consoles in the UML /etc/inittab.\n" \
+ "****\n"
+
static int port_accept(struct port_list *port)
{
struct connection *conn;
@@ -104,6 +113,10 @@ static int port_accept(struct port_list
goto out_free;
}
+ if(atomic_read(&port->wait_count) == 0){
+ os_write_file(fd, NO_WAITER_MSG, sizeof(NO_WAITER_MSG));
+ printk("No one waiting for port\n");
+ }
list_add(&conn->list, &port->pending);
return(1);
@@ -182,6 +195,7 @@ void *port_data(int port_num)
*port = ((struct port_list)
{ .list = LIST_HEAD_INIT(port->list),
+ .wait_count = ATOMIC_INIT(0),
.has_connection = 0,
.sem = __SEMAPHORE_INITIALIZER(port->sem,
0),
@@ -220,9 +234,11 @@ int port_wait(void *data)
struct port_list *port = dev->port;
int fd;
+ atomic_inc(&port->wait_count);
while(1){
+ fd = -ERESTARTSYS;
if(down_interruptible(&port->sem))
- return(-ERESTARTSYS);
+ goto out;
spin_lock(&port->lock);
@@ -254,8 +270,9 @@ int port_wait(void *data)
dev->helper_pid = conn->helper_pid;
dev->telnetd_pid = conn->telnetd_pid;
kfree(conn);
-
- return(fd);
+ out:
+ atomic_dec(&port->wait_count);
+ return fd;
}
void port_remove_dev(void *d)
diff -puN arch/um/drivers/ubd_kern.c~uml-improve-error-reporting arch/um/drivers/ubd_kern.c
--- 25/arch/um/drivers/ubd_kern.c~uml-improve-error-reporting 2005-03-07 22:16:24.000000000 -0800
+++ 25-akpm/arch/um/drivers/ubd_kern.c 2005-03-07 22:16:24.000000000 -0800
@@ -453,6 +453,22 @@ __uml_help(ubd_setup,
" an 's' will cause data to be written to disk on the host immediately.\n\n"
);
+static int udb_setup(char *str)
+{
+ printk("udb%s specified on command line is almost certainly a ubd -> "
+ "udb TYPO\n", str);
+ return(1);
+}
+
+__setup("udb", udb_setup);
+__uml_help(udb_setup,
+"udb\n"
+" This option is here solely to catch ubd -> udb typos, which can be\n\n"
+" to impossible to catch visually unless you specifically look for\n\n"
+" them. The only result of any option starting with 'udb' is an error\n\n"
+" in the boot output.\n\n"
+);
+
static int fakehd_set = 0;
static int fakehd(char *str)
{
@@ -605,7 +621,11 @@ static int ubd_open_dev(struct ubd *dev)
}
}
- if(dev->fd < 0) return(dev->fd);
+ if(dev->fd < 0){
+ printk("Failed to open '%s', errno = %d\n", dev->file,
+ -dev->fd);
+ return(dev->fd);
+ }
if(dev->cow.file != NULL){
err = -ENOMEM;
_