Commit 570ef363 authored by David Hildenbrand's avatar David Hildenbrand Committed by akpm

arm64/pgtable: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE

Let's use one of the type bits: core-mm only supports 5, so there is no
need to consume 6.

Note that we might be able to reuse bit 1, but reusing bit 1 turned out
problematic in the past for PROT_NONE handling; so let's play safe and use
another bit.

Link: https://lkml.kernel.org/r/20220329164329.208407-5-david@redhat.comReviewed-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
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: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 3e20889c
......@@ -14,6 +14,7 @@
* Software defined PTE bits definition.
*/
#define PTE_WRITE (PTE_DBM) /* same as DBM (51) */
#define PTE_SWP_EXCLUSIVE (_AT(pteval_t, 1) << 2) /* only for swp ptes */
#define PTE_DIRTY (_AT(pteval_t, 1) << 55)
#define PTE_SPECIAL (_AT(pteval_t, 1) << 56)
#define PTE_DEVMAP (_AT(pteval_t, 1) << 57)
......
......@@ -402,6 +402,22 @@ static inline pgprot_t mk_pmd_sect_prot(pgprot_t prot)
return __pgprot((pgprot_val(prot) & ~PMD_TABLE_BIT) | PMD_TYPE_SECT);
}
#define __HAVE_ARCH_PTE_SWP_EXCLUSIVE
static inline pte_t pte_swp_mkexclusive(pte_t pte)
{
return set_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
}
static inline int pte_swp_exclusive(pte_t pte)
{
return pte_val(pte) & PTE_SWP_EXCLUSIVE;
}
static inline pte_t pte_swp_clear_exclusive(pte_t pte)
{
return clear_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
}
#ifdef CONFIG_NUMA_BALANCING
/*
* See the comment in include/linux/pgtable.h
......@@ -909,12 +925,13 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
/*
* Encode and decode a swap entry:
* bits 0-1: present (must be zero)
* bits 2-7: swap type
* bits 2: remember PG_anon_exclusive
* bits 3-7: swap type
* bits 8-57: swap offset
* bit 58: PTE_PROT_NONE (must be zero)
*/
#define __SWP_TYPE_SHIFT 2
#define __SWP_TYPE_BITS 6
#define __SWP_TYPE_SHIFT 3
#define __SWP_TYPE_BITS 5
#define __SWP_OFFSET_BITS 50
#define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
#define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
......
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