Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6

[pandora-kernel.git] / sound / core / info.c

diff --git a/sound/core/info.c b/sound/core/info.c
index cc4a53d..b70564e 100644 (file)
--- a/sound/core/info.c
+++ b/sound/core/info.c
@@ -164,40 +164,44 @@ static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig)
 {
        struct snd_info_private_data *data;
        struct snd_info_entry *entry;
-       loff_t ret;
+       loff_t ret = -EINVAL, size;
 
        data = file->private_data;
        entry = data->entry;
-       lock_kernel();
-       switch (entry->content) {
-       case SNDRV_INFO_CONTENT_TEXT:
-               switch (orig) {
-               case SEEK_SET:
-                       file->f_pos = offset;
-                       ret = file->f_pos;
-                       goto out;
-               case SEEK_CUR:
-                       file->f_pos += offset;
-                       ret = file->f_pos;
-                       goto out;
-               case SEEK_END:
-               default:
-                       ret = -EINVAL;
-                       goto out;
-               }
+       mutex_lock(&entry->access);
+       if (entry->content == SNDRV_INFO_CONTENT_DATA &&
+           entry->c.ops->llseek) {
+               offset = entry->c.ops->llseek(entry,
+                                             data->file_private_data,
+                                             file, offset, orig);
+               goto out;
+       }
+       if (entry->content == SNDRV_INFO_CONTENT_DATA)
+               size = entry->size;
+       else
+               size = 0;
+       switch (orig) {
+       case SEEK_SET:
                break;
-       case SNDRV_INFO_CONTENT_DATA:
-               if (entry->c.ops->llseek) {
-                       ret = entry->c.ops->llseek(entry,
-                                                   data->file_private_data,
-                                                   file, offset, orig);
+       case SEEK_CUR:
+               offset += file->f_pos;
+               break;
+       case SEEK_END:
+               if (!size)
                        goto out;
-               }
+               offset += size;
                break;
-       }
-       ret = -ENXIO;
-out:
-       unlock_kernel();
+       default:
+               goto out;
+       }
+       if (offset < 0)
+               goto out;
+       if (size && offset > size)
+               offset = size;
+       file->f_pos = offset;
+       ret = offset;
+ out:
+       mutex_unlock(&entry->access);
        return ret;
 }
 
@@ -232,10 +236,15 @@ static ssize_t snd_info_entry_read(struct file *file, char __user *buffer,
                        return -EFAULT;
                break;
        case SNDRV_INFO_CONTENT_DATA:
-               if (entry->c.ops->read)
+               if (pos >= entry->size)
+                       return 0;
+               if (entry->c.ops->read) {
+                       size = entry->size - pos;
+                       size = min(count, size);
                        size = entry->c.ops->read(entry,
                                                  data->file_private_data,
-                                                 file, buffer, count, pos);
+                                                 file, buffer, size, pos);
+               }
                break;
        }
        if ((ssize_t) size > 0)
@@ -282,10 +291,13 @@ static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer
                size = count;
                break;
        case SNDRV_INFO_CONTENT_DATA:
-               if (entry->c.ops->write)
+               if (entry->c.ops->write && count > 0) {
+                       size_t maxsize = entry->size - pos;
+                       count = min(count, maxsize);
                        size = entry->c.ops->write(entry,
                                                   data->file_private_data,
                                                   file, buffer, count, pos);
+               }
                break;
        }
        if ((ssize_t) size > 0)