42 lines
1.0 KiB
C
42 lines
1.0 KiB
C
/* SPDX-License-Identifier: GPL-2.0
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*
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* Network memory
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*
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* Author: Mina Almasry <almasrymina@google.com>
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*/
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#ifndef _NET_NETMEM_H
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#define _NET_NETMEM_H
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/**
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* typedef netmem_ref - a nonexistent type marking a reference to generic
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* network memory.
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*
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* A netmem_ref currently is always a reference to a struct page. This
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* abstraction is introduced so support for new memory types can be added.
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*
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* Use the supplied helpers to obtain the underlying memory pointer and fields.
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*/
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typedef unsigned long __bitwise netmem_ref;
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/* This conversion fails (returns NULL) if the netmem_ref is not struct page
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* backed.
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*
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* Currently struct page is the only possible netmem, and this helper never
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* fails.
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*/
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static inline struct page *netmem_to_page(netmem_ref netmem)
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{
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return (__force struct page *)netmem;
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}
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/* Converting from page to netmem is always safe, because a page can always be
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* a netmem.
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*/
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static inline netmem_ref page_to_netmem(struct page *page)
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{
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return (__force netmem_ref)page;
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}
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#endif /* _NET_NETMEM_H */
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