[PATCH] uml: return hotplug errors to host

[powerpc.git] / arch / um / drivers / line.c

diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c
index 799fca3..e620ed4 100644 (file)
--- a/arch/um/drivers/line.c
+++ b/arch/um/drivers/line.c
@@ -549,14 +549,16 @@ void close_lines(struct line *lines, int nlines)
                close_chan(&lines[i].chan_list, 0);
 }
 
-static void setup_one_line(struct line *lines, int n, char *init, int init_prio)
+static int setup_one_line(struct line *lines, int n, char *init, int init_prio,
+                         char **error_out)
 {
        struct line *line = &lines[n];
+       int err = -EINVAL;
 
        spin_lock(&line->count_lock);
 
        if(line->tty != NULL){
-               printk("line_setup - device %d is open\n", n);
+               *error_out = "Device is already open";
                goto out;
        }
 
@@ -569,18 +571,22 @@ static void setup_one_line(struct line *lines, int n, char *init, int init_prio)
                        line->valid = 1;
                }
        }
+       err = 0;
 out:
        spin_unlock(&line->count_lock);
+       return err;
 }
 
 /* Common setup code for both startup command line and mconsole initialization.
  * @lines contains the array (of size @num) to modify;
  * @init is the setup string;
+ * @error_out is an error string in the case of failure;
  */
 
-int line_setup(struct line *lines, unsigned int num, char *init)
+int line_setup(struct line *lines, unsigned int num, char *init,
+              char **error_out)
 {
-       int i, n;
+       int i, n, err;
        char *end;
 
        if(*init == '=') {
@@ -591,52 +597,56 @@ int line_setup(struct line *lines, unsigned int num, char *init)
        else {
                n = simple_strtoul(init, &end, 0);
                if(*end != '='){
-                       printk(KERN_ERR "line_setup failed to parse \"%s\"\n",
-                              init);
-                       return 0;
+                       *error_out = "Couldn't parse device number";
+                       return -EINVAL;
                }
                init = end;
        }
        init++;
 
        if (n >= (signed int) num) {
-               printk("line_setup - %d out of range ((0 ... %d) allowed)\n",
-                      n, num - 1);
-               return 0;
+               *error_out = "Device number out of range";
+               return -EINVAL;
+       }
+       else if (n >= 0){
+               err = setup_one_line(lines, n, init, INIT_ONE, error_out);
+               if(err)
+                       return err;
        }
-       else if (n >= 0)
-               setup_one_line(lines, n, init, INIT_ONE);
        else {
-               for(i = 0; i < num; i++)
-                       setup_one_line(lines, i, init, INIT_ALL);
+               for(i = 0; i < num; i++){
+                       err = setup_one_line(lines, i, init, INIT_ALL,
+                                            error_out);
+                       if(err)
+                               return err;
+               }
        }
        return n == -1 ? num : n;
 }
 
 int line_config(struct line *lines, unsigned int num, char *str,
-               const struct chan_opts *opts)
+               const struct chan_opts *opts, char **error_out)
 {
        struct line *line;
        char *new;
        int n;
 
        if(*str == '='){
-               printk("line_config - can't configure all devices from "
-                      "mconsole\n");
-               return 1;
+               *error_out = "Can't configure all devices from mconsole";
+               return -EINVAL;
        }
 
        new = kstrdup(str, GFP_KERNEL);
        if(new == NULL){
-               printk("line_config - kstrdup failed\n");
-               return 1;
+               *error_out = "Failed to allocate memory";
+               return -ENOMEM;
        }
-       n = line_setup(lines, num, new);
+       n = line_setup(lines, num, new, error_out);
        if(n < 0)
-               return 1;
+               return n;
 
        line = &lines[n];
-       return parse_chan_pair(line->init_str, line, n, opts);
+       return parse_chan_pair(line->init_str, line, n, opts, error_out);
 }
 
 int line_get_config(char *name, struct line *lines, unsigned int num, char *str,
@@ -685,13 +695,13 @@ int line_id(char **str, int *start_out, int *end_out)
         return n;
 }
 
-int line_remove(struct line *lines, unsigned int num, int n)
+int line_remove(struct line *lines, unsigned int num, int n, char **error_out)
 {
        int err;
        char config[sizeof("conxxxx=none\0")];
 
        sprintf(config, "%d=none", n);
-       err = line_setup(lines, num, config);
+       err = line_setup(lines, num, config, error_out);
        if(err >= 0)
                err = 0;
        return err;
@@ -740,6 +750,7 @@ static LIST_HEAD(winch_handlers);
 void lines_init(struct line *lines, int nlines, struct chan_opts *opts)
 {
        struct line *line;
+       char *error;
        int i;
 
        for(i = 0; i < nlines; i++){
@@ -754,8 +765,9 @@ void lines_init(struct line *lines, int nlines, struct chan_opts *opts)
                if(line->init_str == NULL)
                        printk("lines_init - kstrdup returned NULL\n");
 
-               if(parse_chan_pair(line->init_str, line, i, opts)){
-                       printk("parse_chan_pair failed for device %d\n", i);
+               if(parse_chan_pair(line->init_str, line, i, opts, &error)){
+                       printk("parse_chan_pair failed for device %d : %s\n",
+                              i, error);
                        line->valid = 0;
                }
        }