diff options
| author | David Hildenbrand <david@redhat.com> | 2025-08-11 14:26:31 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-09-14 02:54:53 +0300 |
| commit | 4c89792ea0a224340ff198abc7caffa211baccd6 (patch) | |
| tree | 337def19fa3a5bbc45d8b91f39e038628ba3cc96 /include | |
| parent | 2db308160b5a191b494746fd167dbbaaead3fb26 (diff) | |
| download | linux-4c89792ea0a224340ff198abc7caffa211baccd6.tar.xz | |
mm: rename vm_ops->find_special_page() to vm_ops->find_normal_page()
... and hide it behind a kconfig option. There is really no need for any
!xen code to perform this check.
The naming is a bit off: we want to find the "normal" page when a PTE was
marked "special". So it's really not "finding a special" page.
Improve the documentation, and add a comment in the code where XEN ends up
performing the pte_mkspecial() through a hypercall. More details can be
found in commit 923b2919e2c3 ("xen/gntdev: mark userspace PTEs as special
on x86 PV guests").
Link: https://lkml.kernel.org/r/20250811112631.759341-12-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Juegren Gross <jgross@suse.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/mm.h | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 8ca7d2fa7134..3868ca1a25f9 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -657,13 +657,21 @@ struct vm_operations_struct { struct mempolicy *(*get_policy)(struct vm_area_struct *vma, unsigned long addr, pgoff_t *ilx); #endif +#ifdef CONFIG_FIND_NORMAL_PAGE /* - * Called by vm_normal_page() for special PTEs to find the - * page for @addr. This is useful if the default behavior - * (using pte_page()) would not find the correct page. + * Called by vm_normal_page() for special PTEs in @vma at @addr. This + * allows for returning a "normal" page from vm_normal_page() even + * though the PTE indicates that the "struct page" either does not exist + * or should not be touched: "special". + * + * Do not add new users: this really only works when a "normal" page + * was mapped, but then the PTE got changed to something weird (+ + * marked special) that would not make pte_pfn() identify the originally + * inserted page. */ - struct page *(*find_special_page)(struct vm_area_struct *vma, - unsigned long addr); + struct page *(*find_normal_page)(struct vm_area_struct *vma, + unsigned long addr); +#endif /* CONFIG_FIND_NORMAL_PAGE */ }; #ifdef CONFIG_NUMA_BALANCING |