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Date: Tue, 12 Dec 2023 18:19:09 -0800
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Subject: Re: [net-next v1 08/16] memory-provider: dmabuf devmem memory
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To: Mina Almasry <almasrymina@google.com>, Jason Gunthorpe <jgg@nvidia.com>
Cc: Shailend Chand <shailend@google.com>, netdev@vger.kernel.org,
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From: David Ahern <dsahern@kernel.org>
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On 12/12/23 6:09 PM, Mina Almasry wrote:
> OK, I imagine this is not that hard to implement - it's really whether
> the change is acceptable to reviewers.
> 
> I figure I can start by implementing a no-op abstraction to page*:
> 
> typedef struct page netmem_t
> 
> and replace the page* in the following places with netmem_t*:
> 
> 1. page_pool API (not internals)
> 2. drivers using the page_pool.
> 3. skb_frag_t.
> 

accessors to skb_frag_t field are now consolidated to
include/linux/skbuff.h (the one IB driver was fixed in Sept by
4ececeb83986), so changing skb_frag_t from bio_vec to something like:

typedef struct skb_frag {
	void *addr;
	unsigned int length;
	unsigned int offset;
};

is trivial. From there, addr can default to `struct page *`. If LSB is
set, strip it and return `struct page_pool_iov *` or `struct buffer_pool *`