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From:   "Chanho Park" <chanho61.park@samsung.com>
To:     "'Christoph Hellwig'" <hch@lst.de>
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        "'Bumyong Lee'" <bumyong.lee@samsung.com>
In-Reply-To: <20210510084406.GA1093@lst.de>
Subject: RE: [PATCH] swiotlb: manipulate orig_addr when tlb_addr has offset
Date:   Mon, 10 May 2021 18:04:17 +0900
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(RESEND due to wrong encrypted message setting)

Hi,

> On Mon, May 10, 2021 at 05:30:57PM +0900, Chanho Park wrote:
> > +static unsigned int swiotlb_align_offset(struct device *dev, u64
> > +addr);
> 
> Please just move swiotlb_align_offset up to avoid the forward declaration.

Okay. I'll move the position of the function next patch.

> 
> >  /*
> >   * Bounce: copy the swiotlb buffer from or back to the original dma
> location
> >   */
> > @@ -346,10 +347,17 @@ static void swiotlb_bounce(struct device *dev,
> phys_addr_t tlb_addr, size_t size
> >  	size_t alloc_size = mem->slots[index].alloc_size;
> >  	unsigned long pfn = PFN_DOWN(orig_addr);
> >  	unsigned char *vaddr = phys_to_virt(tlb_addr);
> > +	unsigned int tlb_offset;
> >
> >  	if (orig_addr == INVALID_PHYS_ADDR)
> >  		return;
> >
> > +	tlb_offset = (unsigned int)tlb_addr & (IO_TLB_SIZE - 1);
> > +	tlb_offset -= swiotlb_align_offset(dev, orig_addr);
> 
> Nit: I'd write this as:
> 
> 	tlb_offset = (tlb_addr & (IO_TLB_SIZE - 1)) -
> 			swiotlb_align_offset(dev, orig_addr);
> 
> as there is no need for the cast, and just having a single assignment is
> easier to follow.

Great. It can be a single assignment as you suggested.

Best Regards,
Chanho Park