Merge master.kernel.org:/pub/scm/linux/kernel/git/herbert/crypto-2.6

[linux-drm-fsl-dcu.git] / arch / um / drivers / mconsole_kern.c

diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index 96f0189327af58260bcbfe14e304faf67cfe513c..542c9ef858f84478c1e75d17a0eeaa48e881912f 100644 (file)
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -25,7 +25,6 @@
 #include "linux/console.h"
 #include "asm/irq.h"
 #include "asm/uaccess.h"
-#include "user_util.h"
 #include "kern_util.h"
 #include "kern.h"
 #include "mconsole.h"
@@ -33,7 +32,6 @@
 #include "irq_user.h"
 #include "init.h"
 #include "os.h"
-#include "umid.h"
 #include "irq_kern.h"
 #include "choose-mode.h"
 
@@ -337,13 +335,15 @@ void mconsole_stop(struct mc_request *req)
        mconsole_reply(req, "", 0, 0);
 }
 
-/* This list is populated by __initcall routines. */
-
+static DEFINE_SPINLOCK(mc_devices_lock);
 static LIST_HEAD(mconsole_devices);
 
 void mconsole_register_dev(struct mc_device *new)
 {
+       spin_lock(&mc_devices_lock);
+       BUG_ON(!list_empty(&new->list));
        list_add(&new->list, &mconsole_devices);
+       spin_unlock(&mc_devices_lock);
 }
 
 static struct mc_device *mconsole_find_dev(char *name)
@@ -367,18 +367,21 @@ struct unplugged_pages {
        void *pages[UNPLUGGED_PER_PAGE];
 };
 
+static DECLARE_MUTEX(plug_mem_mutex);
 static unsigned long long unplugged_pages_count = 0;
-static struct list_head unplugged_pages = LIST_HEAD_INIT(unplugged_pages);
+static LIST_HEAD(unplugged_pages);
 static int unplug_index = UNPLUGGED_PER_PAGE;
 
-static int mem_config(char *str)
+static int mem_config(char *str, char **error_out)
 {
        unsigned long long diff;
        int err = -EINVAL, i, add;
        char *ret;
 
-       if(str[0] != '=')
+       if(str[0] != '='){
+               *error_out = "Expected '=' after 'mem'";
                goto out;
+       }
 
        str++;
        if(str[0] == '-')
@@ -386,15 +389,21 @@ static int mem_config(char *str)
        else if(str[0] == '+'){
                add = 1;
        }
-       else goto out;
+       else {
+               *error_out = "Expected increment to start with '-' or '+'";
+               goto out;
+       }
 
        str++;
        diff = memparse(str, &ret);
-       if(*ret != '\0')
+       if(*ret != '\0'){
+               *error_out = "Failed to parse memory increment";
                goto out;
+       }
 
        diff /= PAGE_SIZE;
 
+       down(&plug_mem_mutex);
        for(i = 0; i < diff; i++){
                struct unplugged_pages *unplugged;
                void *addr;
@@ -435,11 +444,14 @@ static int mem_config(char *str)
                                unplugged = list_entry(entry,
                                                       struct unplugged_pages,
                                                       list);
-                               unplugged->pages[unplug_index++] = addr;
                                err = os_drop_memory(addr, PAGE_SIZE);
-                               if(err)
+                               if(err){
                                        printk("Failed to release memory - "
                                               "errno = %d\n", err);
+                                       *error_out = "Failed to release memory";
+                                       goto out_unlock;
+                               }
+                               unplugged->pages[unplug_index++] = addr;
                        }
 
                        unplugged_pages_count++;
@@ -447,6 +459,8 @@ static int mem_config(char *str)
        }
 
        err = 0;
+out_unlock:
+       up(&plug_mem_mutex);
 out:
        return err;
 }
@@ -470,12 +484,14 @@ static int mem_id(char **str, int *start_out, int *end_out)
        return 0;
 }
 
-static int mem_remove(int n)
+static int mem_remove(int n, char **error_out)
 {
+       *error_out = "Memory doesn't support the remove operation";
        return -EBUSY;
 }
 
 static struct mc_device mem_mc = {
+       .list           = LIST_HEAD_INIT(mem_mc.list),
        .name           = "mem",
        .config         = mem_config,
        .get_config     = mem_get_config,
@@ -542,7 +558,7 @@ static void mconsole_get_config(int (*get_config)(char *, char *, int,
 void mconsole_config(struct mc_request *req)
 {
        struct mc_device *dev;
-       char *ptr = req->request.data, *name;
+       char *ptr = req->request.data, *name, *error_string = "";
        int err;
 
        ptr += strlen("config");
@@ -559,8 +575,8 @@ void mconsole_config(struct mc_request *req)
                ptr++;
 
        if(*ptr == '='){
-               err = (*dev->config)(name);
-               mconsole_reply(req, "", err, 0);
+               err = (*dev->config)(name, &error_string);
+               mconsole_reply(req, error_string, err, 0);
        }
        else mconsole_get_config(dev->get_config, req, name);
 }
@@ -595,13 +611,19 @@ void mconsole_remove(struct mc_request *req)
                goto out;
        }
 
-       err = (*dev->remove)(n);
+       err_msg = NULL;
+       err = (*dev->remove)(n, &err_msg);
        switch(err){
+       case 0:
+               err_msg = "";
+               break;
        case -ENODEV:
-               err_msg = "Device doesn't exist";
+               if(err_msg == NULL)
+                       err_msg = "Device doesn't exist";
                break;
        case -EBUSY:
-               err_msg = "Device is currently open";
+               if(err_msg == NULL)
+                       err_msg = "Device is currently open";
                break;
        default:
                break;
@@ -615,7 +637,7 @@ struct mconsole_output {
        struct mc_request *req;
 };
 
-static DEFINE_SPINLOCK(console_lock);
+static DEFINE_SPINLOCK(client_lock);
 static LIST_HEAD(clients);
 static char console_buf[MCONSOLE_MAX_DATA];
 static int console_index = 0;
@@ -670,16 +692,18 @@ static void with_console(struct mc_request *req, void (*proc)(void *),
        unsigned long flags;
 
        entry.req = req;
+       spin_lock_irqsave(&client_lock, flags);
        list_add(&entry.list, &clients);
-       spin_lock_irqsave(&console_lock, flags);
+       spin_unlock_irqrestore(&client_lock, flags);
 
        (*proc)(arg);
 
        mconsole_reply_len(req, console_buf, console_index, 0, 0);
        console_index = 0;
 
-       spin_unlock_irqrestore(&console_lock, flags);
+       spin_lock_irqsave(&client_lock, flags);
        list_del(&entry.list);
+       spin_unlock_irqrestore(&client_lock, flags);
 }
 
 #ifdef CONFIG_MAGIC_SYSRQ