string: factorize skip_spaces and export it to be generally available

[safe/jmp/linux-2.6] / sound / core / control.c

diff --git a/sound/core/control.c b/sound/core/control.c
index 4b20fa2..268ab74 100644 (file)
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -75,7 +75,7 @@ static int snd_ctl_open(struct inode *inode, struct file *file)
        ctl->card = card;
        ctl->prefer_pcm_subdevice = -1;
        ctl->prefer_rawmidi_subdevice = -1;
-       ctl->pid = current->pid;
+       ctl->pid = get_pid(task_pid(current));
        file->private_data = ctl;
        write_lock_irqsave(&card->ctl_files_rwlock, flags);
        list_add_tail(&ctl->list, &card->ctl_files);
@@ -125,6 +125,7 @@ static int snd_ctl_release(struct inode *inode, struct file *file)
                                control->vd[idx].owner = NULL;
        up_write(&card->controls_rwsem);
        snd_ctl_empty_read_queue(ctl);
+       put_pid(ctl->pid);
        kfree(ctl);
        module_put(card->module);
        snd_card_file_remove(card, file);
@@ -414,7 +415,7 @@ int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
 EXPORT_SYMBOL(snd_ctl_remove_id);
 
 /**
- * snd_ctl_remove_unlocked_id - remove the unlocked control of the given id and release it
+ * snd_ctl_remove_user_ctl - remove and release the unlocked user control
  * @file: active control handle
  * @id: the control id to remove
  *
@@ -423,8 +424,8 @@ EXPORT_SYMBOL(snd_ctl_remove_id);
  * 
  * Returns 0 if successful, or a negative error code on failure.
  */
-static int snd_ctl_remove_unlocked_id(struct snd_ctl_file * file,
-                                     struct snd_ctl_elem_id *id)
+static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file,
+                                  struct snd_ctl_elem_id *id)
 {
        struct snd_card *card = file->card;
        struct snd_kcontrol *kctl;
@@ -433,15 +434,23 @@ static int snd_ctl_remove_unlocked_id(struct snd_ctl_file * file,
        down_write(&card->controls_rwsem);
        kctl = snd_ctl_find_id(card, id);
        if (kctl == NULL) {
-               up_write(&card->controls_rwsem);
-               return -ENOENT;
+               ret = -ENOENT;
+               goto error;
+       }
+       if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) {
+               ret = -EINVAL;
+               goto error;
        }
        for (idx = 0; idx < kctl->count; idx++)
                if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) {
-                       up_write(&card->controls_rwsem);
-                       return -EBUSY;
+                       ret = -EBUSY;
+                       goto error;
                }
        ret = snd_ctl_remove(card, kctl);
+       if (ret < 0)
+               goto error;
+       card->user_ctl_count--;
+error:
        up_write(&card->controls_rwsem);
        return ret;
 }
@@ -664,7 +673,7 @@ static int snd_ctl_elem_info(struct snd_ctl_file *ctl,
                        info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK;
                        if (vd->owner == ctl)
                                info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER;
-                       info->owner = vd->owner_pid;
+                       info->owner = pid_vnr(vd->owner->pid);
                } else {
                        info->owner = -1;
                }
@@ -723,14 +732,11 @@ static int snd_ctl_elem_read_user(struct snd_card *card,
 {
        struct snd_ctl_elem_value *control;
        int result;
-       
-       control = kmalloc(sizeof(*control), GFP_KERNEL);
-       if (control == NULL)
-               return -ENOMEM; 
-       if (copy_from_user(control, _control, sizeof(*control))) {
-               kfree(control);
-               return -EFAULT;
-       }
+
+       control = memdup_user(_control, sizeof(*control));
+       if (IS_ERR(control))
+               return PTR_ERR(control);
+
        snd_power_lock(card);
        result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
        if (result >= 0)
@@ -784,13 +790,10 @@ static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
        struct snd_card *card;
        int result;
 
-       control = kmalloc(sizeof(*control), GFP_KERNEL);
-       if (control == NULL)
-               return -ENOMEM; 
-       if (copy_from_user(control, _control, sizeof(*control))) {
-               kfree(control);
-               return -EFAULT;
-       }
+       control = memdup_user(_control, sizeof(*control));
+       if (IS_ERR(control))
+               return PTR_ERR(control);
+
        card = file->card;
        snd_power_lock(card);
        result = snd_power_wait(card, SNDRV_CTL_POWER_D0);
@@ -825,7 +828,6 @@ static int snd_ctl_elem_lock(struct snd_ctl_file *file,
                        result = -EBUSY;
                else {
                        vd->owner = file;
-                       vd->owner_pid = current->pid;
                        result = 0;
                }
        }
@@ -856,7 +858,6 @@ static int snd_ctl_elem_unlock(struct snd_ctl_file *file,
                        result = -EPERM;
                else {
                        vd->owner = NULL;
-                       vd->owner_pid = 0;
                        result = 0;
                }
        }
@@ -916,13 +917,10 @@ static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol,
        if (op_flag > 0) {
                if (size > 1024 * 128)  /* sane value */
                        return -EINVAL;
-               new_data = kmalloc(size, GFP_KERNEL);
-               if (new_data == NULL)
-                       return -ENOMEM;
-               if (copy_from_user(new_data, tlv, size)) {
-                       kfree(new_data);
-                       return -EFAULT;
-               }
+
+               new_data = memdup_user(tlv, size);
+               if (IS_ERR(new_data))
+                       return PTR_ERR(new_data);
                change = ue->tlv_data_size != size;
                if (!change)
                        change = memcmp(ue->tlv_data, new_data, size);
@@ -960,7 +958,7 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file,
        
        if (card->user_ctl_count >= MAX_USER_CONTROLS)
                return -ENOMEM;
-       if (info->count > 1024)
+       if (info->count < 1)
                return -EINVAL;
        access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
                (info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
@@ -1061,18 +1059,10 @@ static int snd_ctl_elem_remove(struct snd_ctl_file *file,
                               struct snd_ctl_elem_id __user *_id)
 {
        struct snd_ctl_elem_id id;
-       int err;
 
        if (copy_from_user(&id, _id, sizeof(id)))
                return -EFAULT;
-       err = snd_ctl_remove_unlocked_id(file, &id);
-       if (! err) {
-               struct snd_card *card = file->card;
-               down_write(&card->controls_rwsem);
-               card->user_ctl_count--;
-               up_write(&card->controls_rwsem);
-       }
-       return err;
+       return snd_ctl_remove_user_ctl(file, &id);
 }
 
 static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr)
@@ -1129,7 +1119,7 @@ static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file,
                goto __kctl_end;
        }
        if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) {
-               if (file && vd->owner != NULL && vd->owner != file) {
+               if (vd->owner != NULL && vd->owner != file) {
                        err = -EPERM;
                        goto __kctl_end;
                }