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powerpc/pgtable: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE for book3s

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Right now, the last 5 bits (0x1f) of the swap entry are used for the type
and the bit before that (0x20) is used for _PAGE_SWP_SOFT_DIRTY.  We
cannot use 0x40, as that collides with _RPAGE_RSV1 -- contained in
_PAGE_HPTEFLAGS.  The next candidate would be _RPAGE_SW3 (0x200) -- which
is used for _PAGE_SOFT_DIRTY for !swp ptes.

So let's just use _PAGE_SOFT_DIRTY for _PAGE_SWP_SOFT_DIRTY (to make it
easier to grasp) and use 0x20 now for _PAGE_SWP_EXCLUSIVE.

Link: https://lkml.kernel.org/r/20220329164329.208407-9-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Liang Zhang <zhangliang5@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Oded Gabbay <oded.gabbay@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pedro Demarchi Gomes <pedrodemargomes@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
David Hildenbrand 2022-05-09 18:20:47 -07:00 committed by akpm
parent 03ac1b71fc
commit bff9beaa2e
1 changed files with 20 additions and 1 deletions
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21
arch/powerpc/include/asm/book3s/64/pgtable.h
View file

@ -752,6 +752,7 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
*/ \
BUILD_BUG_ON(_PAGE_HPTEFLAGS & SWP_TYPE_MASK); \
BUILD_BUG_ON(_PAGE_HPTEFLAGS & _PAGE_SWP_SOFT_DIRTY); \
BUILD_BUG_ON(_PAGE_HPTEFLAGS & _PAGE_SWP_EXCLUSIVE); \
} while (0)
#define SWP_TYPE_BITS 5
@ -772,11 +773,13 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
#define __swp_entry_to_pmd(x) (pte_pmd(__swp_entry_to_pte(x)))
#ifdef CONFIG_MEM_SOFT_DIRTY
#define _PAGE_SWP_SOFT_DIRTY _PAGE_NON_IDEMPOTENT
#define _PAGE_SWP_SOFT_DIRTY _PAGE_SOFT_DIRTY
#else
#define _PAGE_SWP_SOFT_DIRTY 0UL
#endif /* CONFIG_MEM_SOFT_DIRTY */
#define _PAGE_SWP_EXCLUSIVE _PAGE_NON_IDEMPOTENT
#ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY
static inline pte_t pte_swp_mksoft_dirty(pte_t pte)
{
@ -794,6 +797,22 @@ static inline pte_t pte_swp_clear_soft_dirty(pte_t pte)
}
#endif /* CONFIG_HAVE_ARCH_SOFT_DIRTY */
#define __HAVE_ARCH_PTE_SWP_EXCLUSIVE
static inline pte_t pte_swp_mkexclusive(pte_t pte)
{
return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_SWP_EXCLUSIVE));
}
static inline int pte_swp_exclusive(pte_t pte)
{
return !!(pte_raw(pte) & cpu_to_be64(_PAGE_SWP_EXCLUSIVE));
}
static inline pte_t pte_swp_clear_exclusive(pte_t pte)
{
return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_SWP_EXCLUSIVE));
}
static inline bool check_pte_access(unsigned long access, unsigned long ptev)
{
/*