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d08d4e7cd6
Cease using 4KB pages to host two 2KB PTEs. That greatly
simplifies the memory management code at the expense of
page tables memory footprint.
Instead of two PTEs per 4KB page use only upper half of
the parent page for a single PTE. With that the list of
half-used pages pgtable_list becomes unneeded.
Further, the upper byte of the parent page _refcount
counter does not need to be used for fragments tracking
and could be left alone.
Commit 8211dad627 ("s390: add pte_free_defer() for
pgtables sharing page") introduced the use of PageActive
flag to coordinate a deferred free with 2KB page table
fragments tracking. Since there is no tracking anymore,
there is no need for using PageActive flag.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
43 lines
1.2 KiB
C
43 lines
1.2 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __MMU_H
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#define __MMU_H
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#include <linux/cpumask.h>
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#include <linux/errno.h>
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#include <asm/asm-extable.h>
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typedef struct {
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spinlock_t lock;
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cpumask_t cpu_attach_mask;
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atomic_t flush_count;
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unsigned int flush_mm;
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struct list_head gmap_list;
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unsigned long gmap_asce;
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unsigned long asce;
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unsigned long asce_limit;
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unsigned long vdso_base;
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/* The mmu context belongs to a secure guest. */
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atomic_t protected_count;
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/*
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* The following bitfields need a down_write on the mm
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* semaphore when they are written to. As they are only
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* written once, they can be read without a lock.
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*
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* The mmu context allocates 4K page tables.
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*/
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unsigned int alloc_pgste:1;
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/* The mmu context uses extended page tables. */
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unsigned int has_pgste:1;
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/* The mmu context uses storage keys. */
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unsigned int uses_skeys:1;
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/* The mmu context uses CMM. */
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unsigned int uses_cmm:1;
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/* The gmaps associated with this context are allowed to use huge pages. */
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unsigned int allow_gmap_hpage_1m:1;
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} mm_context_t;
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#define INIT_MM_CONTEXT(name) \
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.context.lock = __SPIN_LOCK_UNLOCKED(name.context.lock), \
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.context.gmap_list = LIST_HEAD_INIT(name.context.gmap_list),
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#endif
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