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#include <linux/mm.h>
//
// The following kernel commit changed the get_user_pages_remote()
// function signature and added the inlined get_user_page_vma_remote()
//
// commit ca5e863233e8f6acd1792fd85d6bc2729a1b2c10
// Author: Lorenzo Stoakes <lstoakes@gmail.com>
// Date: Wed May 17 20:25:39 2023 +0100
//
// mm/gup: remove vmas parameter from get_user_pages_remote()
//
// The only instances of get_user_pages_remote() invocations which used the
// vmas parameter were for a single page which can instead simply look up the
// VMA directly. In particular:-
//
// - __update_ref_ctr() looked up the VMA but did nothing with it so we simply
// remove it.
//
// - __access_remote_vm() was already using vma_lookup() when the original
// lookup failed so by doing the lookup directly this also de-duplicates the
// code.
//
// We are able to perform these VMA operations as we already hold the
// mmap_lock in order to be able to call get_user_pages_remote().
//
// As part of this work we add get_user_page_vma_remote() which abstracts the
// VMA lookup, error handling and decrementing the page reference count should
// the VMA lookup fail.
//
// This forms part of a broader set of patches intended to eliminate the vmas
// parameter altogether.
struct page *get_user_page_vma_remote_wrapper(struct mm_struct *mm,
unsigned long addr,
unsigned int gup_flags,
struct vm_area_struct **vmaps);
struct page *get_user_page_vma_remote_wrapper(struct mm_struct *mm,
unsigned long addr,
unsigned int gup_flags,
struct vm_area_struct **vmaps)
{
return get_user_page_vma_remote(mm, addr, gup_flags, vmaps);
}
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