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Date:   Wed, 13 Dec 2023 22:34:43 -0800
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Subject: Re: [RFC PATCH net-next v1 2/4] net: introduce abstraction for
 network memory
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To:     Mina Almasry <almasrymina@google.com>,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        bpf@vger.kernel.org
Cc:     Thomas Gleixner <tglx@linutronix.de>,
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        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
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References: <20231214020530.2267499-1-almasrymina@google.com>
 <20231214020530.2267499-3-almasrymina@google.com>
From:   David Ahern <dsahern@kernel.org>
In-Reply-To: <20231214020530.2267499-3-almasrymina@google.com>
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On 12/13/23 7:05 PM, Mina Almasry wrote:
> diff --git a/include/net/netmem.h b/include/net/netmem.h
> new file mode 100644
> index 000000000000..e4309242d8be
> --- /dev/null
> +++ b/include/net/netmem.h
> @@ -0,0 +1,35 @@
> +/* SPDX-License-Identifier: GPL-2.0
> + *
> + * netmem.h
> + *	Author:	Mina Almasry <almasrymina@google.com>
> + *	Copyright (C) 2023 Google LLC
> + */
> +
> +#ifndef _NET_NETMEM_H
> +#define _NET_NETMEM_H
> +
> +struct netmem {
> +	union {
> +		struct page page;
> +
> +		/* Stub to prevent compiler implicitly converting from page*
> +		 * to netmem_t* and vice versa.
> +		 *
> +		 * Other memory type(s) net stack would like to support
> +		 * can be added to this union.
> +		 */
> +		void *addr;
> +	};
> +};
> +
> +static inline struct page *netmem_to_page(struct netmem *netmem)
> +{
> +	return &netmem->page;
> +}
> +
> +static inline struct netmem *page_to_netmem(struct page *page)
> +{
> +	return (struct netmem *)page;

container_of; no typecasts.


> +}
> +
> +#endif /* _NET_NETMEM_H */