Re: New DRM driver model - gets rid of DRM() macros!
From: Keith Whitwell
Date: Wed Sep 29 2004 - 08:40:16 EST
Christoph Hellwig wrote:
On Wed, Sep 29, 2004 at 02:29:24PM +0100, Keith Whitwell wrote:
Christoph Hellwig wrote:
- drm_flush is a noop. a NULL ->flush does the same thing, just easier
- dito or ->poll
- dito for ->read
Pretty sure you couldn't get away with null for these in 2.4, at least.
Umm, of course you could. There's only a hanfull instance defining a
->flush at all. Similarly all file_ops for regular files and many char
devices don't have ->poll. no ->read is pretty rare but 2.4 chæcks it
aswell.
I tried it, led to crashes (panics, I guess) & the change had to be reverted.
On reverting the crashes stopped. This was for poll and read:
revision 1.12
date: 2003-04-23 23:42:28 +0000; author: keithw; state: Exp; lines: +13 -0
Install dummy/noop read & poll fops unless the driver has replacements.
----------------------------
revision 1.11
date: 2003-04-22 08:06:13 +0000; author: keithw; state: Exp; lines: +0 -94
remove DRM read, poll and write_string
I didn't do any more investigation & the behaviour may well be different
nowadays.
Keith
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