Re: [patch] synclink.c compiler optimiation fix

[Christoph Hellwig]

On Wed, Sep 07, 2005 at 12:02:23PM -0500, Paul Fulghum wrote:
> -	u16 count;	/* buffer size/data count */
> -	u16 status;	/* Control/status field */
> -	u16 rcc;	/* character count field */
> +	volatile u16 count;	/* buffer size/data count */
> +	volatile u16 status;	/* Control/status field */
> +	volatile u16 rcc;	/* character count field */

this is wrong.  The structure is in ioremaped memory so you must
use reads/writes to access them instead.  volatile usage in drivers
is never okay - if you are accessing I/O memory you need to use
proper acessors, if it is normal memory and you want atomic sematics
you need to use the atomic_t type and the operators defined on it.

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