[Spice-devel] [PATCH 3.1/12] Store QXLInstance in CursorItem

[Frediano Ziglio]

> 
> From: Marc-André Lureau <marcandre.lureau at gmail.com>
> 
> Doing so allows us to remove the extra QXLInstance parameter from
> cursor_item_unref() and makes the code a bit cleaner.
> 
> Also add cursor_item_ref().
> 
> Signed-off-by: Jonathon Jongsma <jjongsma at redhat.com>
> ---
>  server/cursor-channel.c | 70
>  +++++++++++++++++++++++++++----------------------
>  server/cursor-channel.h |  9 ++++---
>  2 files changed, 44 insertions(+), 35 deletions(-)
> 
> diff --git a/server/cursor-channel.c b/server/cursor-channel.c
> index 6cc2b93..2d7afc6 100644
> --- a/server/cursor-channel.c
> +++ b/server/cursor-channel.c
> @@ -25,55 +25,58 @@
>  #include "cache_item.tmpl.c"
>  #undef CLIENT_CURSOR_CACHE
>  
> -static inline CursorItem *alloc_cursor_item(void)
> +CursorItem *cursor_item_new(QXLInstance *qxl, RedCursorCmd *cmd, uint32_t
> group_id)
>  {
>      CursorItem *cursor_item;
>  
> +    spice_return_val_if_fail(cmd != NULL, NULL);
> +
>      cursor_item = g_slice_new0(CursorItem);
> +    cursor_item->qxl = qxl;
>      cursor_item->refs = 1;
> +    cursor_item->group_id = group_id;
> +    cursor_item->red_cursor = cmd;
>  
>      return cursor_item;
>  }
>  
> -CursorItem *cursor_item_new(RedCursorCmd *cmd, uint32_t group_id)
> +CursorItem *cursor_item_ref(CursorItem *item)
>  {
> -    CursorItem *cursor_item;
> -
> -    spice_return_val_if_fail(cmd != NULL, NULL);
> -    cursor_item = alloc_cursor_item();
> +    spice_return_val_if_fail(item != NULL, NULL);
> +    spice_return_val_if_fail(item->refs > 0, NULL);

This catch a memory corruption, should abort the program,
I suggest spice_error, spice_critical or spice_assert.

>  
> -    cursor_item->group_id = group_id;
> -    cursor_item->red_cursor = cmd;
> +    item->refs++;
>  
> -    return cursor_item;
> +    return item;
>  }
>  
> -void cursor_item_unref(QXLInstance *qxl, CursorItem *cursor)
> +void cursor_item_unref(CursorItem *item)
>  {
> -    if (!--cursor->refs) {
> -        QXLReleaseInfoExt release_info_ext;
> -        RedCursorCmd *cursor_cmd;
> -
> -        cursor_cmd = cursor->red_cursor;
> -        release_info_ext.group_id = cursor->group_id;
> -        release_info_ext.info = cursor_cmd->release_info;
> -        qxl->st->qif->release_resource(qxl, release_info_ext);
> -        red_put_cursor_cmd(cursor_cmd);
> -        free(cursor_cmd);
> -
> -        g_slice_free(CursorItem, cursor);
> -    }
> +    QXLReleaseInfoExt release_info_ext;
> +    RedCursorCmd *cursor_cmd;
> +
> +    spice_return_if_fail(item != NULL);
> +
> +    if (--item->refs)
> +        return;
> +
> +    cursor_cmd = item->red_cursor;
> +    release_info_ext.group_id = item->group_id;
> +    release_info_ext.info = cursor_cmd->release_info;
> +    item->qxl->st->qif->release_resource(item->qxl, release_info_ext);
> +    red_put_cursor_cmd(cursor_cmd);
> +    free(cursor_cmd);
> +
> +    g_slice_free(CursorItem, item);
> +
>  }
>  
>  static void cursor_set_item(CursorChannel *cursor, CursorItem *item)
>  {
>      if (cursor->item)
> -        cursor_item_unref(red_worker_get_qxl(cursor->common.worker),
> cursor->item);
> -
> -    if (item)
> -        item->refs++;
> +        cursor_item_unref(cursor->item);
>  
> -    cursor->item = item;
> +    cursor->item = item ? cursor_item_ref(item) : NULL;
>  }
>  

Are these tests worth doing or can we assume that a NULL pointer is expected (like
unref(NULL) and ref(NULL) do nothing) ? This would make cursor_set_item like

static void cursor_set_item(CursorChannel *cursor, CursorItem *item)
{
    cursor_item_unref(cursor->item);

    cursor->item = cursor_item_ref(item);
}


On naming, sometimes is cursor_item sometimes item. I would prefer cursor_item.

>  static PipeItem *new_cursor_pipe_item(RedChannelClient *rcc, void *data, int
>  num)
> @@ -155,7 +158,7 @@ static void put_cursor_pipe_item(CursorChannelClient
> *ccc, CursorPipeItem *pipe_
>  
>      spice_assert(!pipe_item_is_linked(&pipe_item->base));
>  
> -    cursor_item_unref(red_worker_get_qxl(ccc->common.worker),
> pipe_item->cursor_item);
> +    cursor_item_unref(pipe_item->cursor_item);
>      free(pipe_item);
>  }
>  
> @@ -411,7 +414,11 @@ void cursor_channel_process_cmd(CursorChannel *cursor,
> RedCursorCmd *cursor_cmd,
>      CursorItem *cursor_item;
>      int cursor_show = FALSE;
>  
> -    cursor_item = cursor_item_new(cursor_cmd, group_id);
> +    spice_return_if_fail(cursor);
> +    spice_return_if_fail(cursor_cmd);
> +
> +    cursor_item = cursor_item_new(red_worker_get_qxl(cursor->common.worker),
> +                                  cursor_cmd, group_id);
>  
>      switch (cursor_cmd->type) {
>      case QXL_CURSOR_SET:
> @@ -439,7 +446,8 @@ void cursor_channel_process_cmd(CursorChannel *cursor,
> RedCursorCmd *cursor_cmd,
>          red_channel_pipes_new_add(&cursor->common.base,
>          new_cursor_pipe_item,
>                                    (void*)cursor_item);
>      }
> -    cursor_item_unref(red_worker_get_qxl(cursor->common.worker),
> cursor_item);
> +
> +    cursor_item_unref(cursor_item);
>  }
>  
>  void cursor_channel_reset(CursorChannel *cursor)
> diff --git a/server/cursor-channel.h b/server/cursor-channel.h
> index 2c19859..8b49df7 100644
> --- a/server/cursor-channel.h
> +++ b/server/cursor-channel.h
> @@ -33,6 +33,7 @@
>  #define CURSOR_CACHE_HASH_KEY(id) ((id) & CURSOR_CACHE_HASH_MASK)
>  
>  typedef struct CursorItem {
> +    QXLInstance *qxl;
>      uint32_t group_id;
>      int refs;
>      RedCursorCmd *red_cursor;
> @@ -83,14 +84,14 @@ void                 cursor_channel_reset
> (CursorChannel *cursor);
>  void                 cursor_channel_process_cmd (CursorChannel *cursor,
>  RedCursorCmd *cursor_cmd,
>                                                   uint32_t group_id);
>  
> -CursorItem*          cursor_item_new            (RedCursorCmd *cmd, uint32_t
> group_id);
> -void                 cursor_item_unref          (QXLInstance *qxl,
> CursorItem *cursor);
> -
> -
>  CursorChannelClient *cursor_channel_client_new(CommonChannel *common,
>                                                 RedClient *client, RedsStream
>                                                 *stream,
>                                                 int mig_target,
>                                                 uint32_t *common_caps, int
>                                                 num_common_caps,
>                                                 uint32_t *caps, int
>                                                 num_caps);
>  
> +CursorItem*          cursor_item_new            (QXLInstance *qxl,
> RedCursorCmd *cmd, uint32_t group_id);
> +CursorItem*          cursor_item_ref            (CursorItem *cursor);
> +void                 cursor_item_unref          (CursorItem *cursor);
> +
>  #endif /* CURSOR_CHANNEL_H_ */

Frediano