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Date:   Sat, 20 May 2023 11:28:44 +0800
From:   Baoquan He <bhe@redhat.com>
To:     Christoph Hellwig <hch@infradead.org>
Cc:     linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
        linux-mm@kvack.org, arnd@arndb.de, christophe.leroy@csgroup.eu,
        agordeev@linux.ibm.com, wangkefeng.wang@huawei.com,
        schnelle@linux.ibm.com, David.Laight@aculab.com, shorne@gmail.com,
        willy@infradead.org, deller@gmx.de
Subject: Re: [PATCH v5 RESEND 14/17] mm/ioremap: Consider IOREMAP space in
 generic ioremap
Message-ID: <ZGg+bHE4g4/s6mGI@MiWiFi-R3L-srv>
References: <20230515090848.833045-1-bhe@redhat.com>
 <20230515090848.833045-15-bhe@redhat.com>
 <ZGR3Ft27kdgXKKfp@infradead.org>
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On 05/16/23 at 11:41pm, Christoph Hellwig wrote:
> On Mon, May 15, 2023 at 05:08:45PM +0800, Baoquan He wrote:
> > @@ -35,8 +35,13 @@ void __iomem *generic_ioremap_prot(phys_addr_t phys_addr, size_t size,
> >  	if (!ioremap_allowed(phys_addr, size, pgprot_val(prot)))
> >  		return NULL;
> >  
> > +#ifdef IOREMAP_START
> > +	area = __get_vm_area_caller(size, VM_IOREMAP, IOREMAP_START,
> > +				    IOREMAP_END, __builtin_return_address(0));
> > +#else
> >  	area = get_vm_area_caller(size, VM_IOREMAP,
> >  			__builtin_return_address(0));
> > +#endif
> 
> I think this would be cleaner if we'd just always use
> __get_vm_area_caller and at the top of the file add a:
> 
> #ifndef IOREMAP_START
> #define IOREMAP_START	VMALLOC_START
> #define IOREMAP_END	VMALLOC_END
> #endif
> 
> Together with a little comment that ioremap often, but not always
> uses the generic vmalloc area.

Great idea, will do as suggested.