The future of host_scribble

The future of host_scribble

[Matthew Wilcox]

In scsi_cmnd there's an element called host_scribble.  The name and the
comment by it were sufficiently confusing that I didn't realise that this
field is basically for the host's private data.  Any objections to something
like this, assuming I also submit a patch that converts all the drivers?

+++ include/scsi/scsi_cmnd.h    2005-04-20 20:16:41.562034944 -0400
@@ -129,13 +129,8 @@
         */
        struct scsi_pointer SCp;        /* Scratchpad used by some host adapters */
 
-       unsigned char *host_scribble;   /* The host adapter is allowed to
-                                          * call scsi_malloc and get some memory
-                                          * and hang it here.     The host adapter
-                                          * is also expected to call scsi_free
-                                          * to release this memory.  (The memory
-                                          * obtained by scsi_malloc is guaranteed
-                                          * to be at an address < 16Mb). */
+       void *host_data;        /* Pointer to the host's data structure
+                                * associated with this command. */
 
        int result;             /* Status code from lower level driver */
 
(the only remaining references to scsi_malloc are in comments ... I'll
submit a different patch to remove those too)

-- 
"Next the statesmen will invent cheap lies, putting the blame upon 
the nation that is attacked, and every man will be glad of those
conscience-soothing falsities, and will diligently study them, and refuse
to examine any refutations of them; and thus he will by and by convince 
himself that the war is just, and will thank God for the better sleep 
he enjoys after this process of grotesque self-deception." -- Mark Twain

Re: The future of host_scribble

[Christoph Hellwig]

On Thu, Apr 21, 2005 at 01:23:33AM +0100, Matthew Wilcox wrote:
> 
> In scsi_cmnd there's an element called host_scribble.  The name and the
> comment by it were sufficiently confusing that I didn't realise that this
> field is basically for the host's private data.  Any objections to something
> like this, assuming I also submit a patch that converts all the drivers?

Actually the situation about private data in scsi_cmnd is worse, there's
another private data, that's the scsi_pointer structure embedded as SCp
member.  If we're going to fix up naming we should find a way to fixup
both an have a sensible name for both embedded and out of struct private
data.  I somehow doubt it's going to happen before we drop support for
gcc 2.95 and thus can use anonymous unions :)