From 6778948f9de86c3cfaf36725a7c87dcff9ba247f Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Mon, 11 Dec 2023 08:20:59 +0000
Subject: [PATCH] kernel_5.10 no rt
---
kernel/mm/highmem.c | 262 +++-------------------------------------------------
1 files changed, 15 insertions(+), 247 deletions(-)
diff --git a/kernel/mm/highmem.c b/kernel/mm/highmem.c
index 72b9a2d..1352a27 100644
--- a/kernel/mm/highmem.c
+++ b/kernel/mm/highmem.c
@@ -31,6 +31,10 @@
#include <asm/tlbflush.h>
#include <linux/vmalloc.h>
+#if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
+DEFINE_PER_CPU(int, __kmap_atomic_idx);
+#endif
+
/*
* Virtual_count is not a pure "count".
* 0 means that it is not mapped, and has not been mapped
@@ -104,7 +108,9 @@
atomic_long_t _totalhigh_pages __read_mostly;
EXPORT_SYMBOL(_totalhigh_pages);
-unsigned int __nr_free_highpages (void)
+EXPORT_PER_CPU_SYMBOL(__kmap_atomic_idx);
+
+unsigned int nr_free_highpages (void)
{
struct zone *zone;
unsigned int pages = 0;
@@ -141,7 +147,7 @@
do { spin_unlock(&kmap_lock); (void)(flags); } while (0)
#endif
-struct page *__kmap_to_page(void *vaddr)
+struct page *kmap_to_page(void *vaddr)
{
unsigned long addr = (unsigned long)vaddr;
@@ -152,7 +158,7 @@
return virt_to_page(addr);
}
-EXPORT_SYMBOL(__kmap_to_page);
+EXPORT_SYMBOL(kmap_to_page);
static void flush_all_zero_pkmaps(void)
{
@@ -194,7 +200,10 @@
flush_tlb_kernel_range(PKMAP_ADDR(0), PKMAP_ADDR(LAST_PKMAP));
}
-void __kmap_flush_unused(void)
+/**
+ * kmap_flush_unused - flush all unused kmap mappings in order to remove stray mappings
+ */
+void kmap_flush_unused(void)
{
lock_kmap();
flush_all_zero_pkmaps();
@@ -358,250 +367,9 @@
if (need_wakeup)
wake_up(pkmap_map_wait);
}
+
EXPORT_SYMBOL(kunmap_high);
-#endif /* CONFIG_HIGHMEM */
-
-#ifdef CONFIG_KMAP_LOCAL
-
-#include <asm/kmap_size.h>
-
-/*
- * With DEBUG_HIGHMEM the stack depth is doubled and every second
- * slot is unused which acts as a guard page
- */
-#ifdef CONFIG_DEBUG_HIGHMEM
-# define KM_INCR 2
-#else
-# define KM_INCR 1
-#endif
-
-static inline int kmap_local_idx_push(void)
-{
- WARN_ON_ONCE(in_irq() && !irqs_disabled());
- current->kmap_ctrl.idx += KM_INCR;
- BUG_ON(current->kmap_ctrl.idx >= KM_MAX_IDX);
- return current->kmap_ctrl.idx - 1;
-}
-
-static inline int kmap_local_idx(void)
-{
- return current->kmap_ctrl.idx - 1;
-}
-
-static inline void kmap_local_idx_pop(void)
-{
- current->kmap_ctrl.idx -= KM_INCR;
- BUG_ON(current->kmap_ctrl.idx < 0);
-}
-
-#ifndef arch_kmap_local_post_map
-# define arch_kmap_local_post_map(vaddr, pteval) do { } while (0)
-#endif
-
-#ifndef arch_kmap_local_pre_unmap
-# define arch_kmap_local_pre_unmap(vaddr) do { } while (0)
-#endif
-
-#ifndef arch_kmap_local_post_unmap
-# define arch_kmap_local_post_unmap(vaddr) do { } while (0)
-#endif
-
-#ifndef arch_kmap_local_map_idx
-#define arch_kmap_local_map_idx(idx, pfn) kmap_local_calc_idx(idx)
-#endif
-
-#ifndef arch_kmap_local_unmap_idx
-#define arch_kmap_local_unmap_idx(idx, vaddr) kmap_local_calc_idx(idx)
-#endif
-
-#ifndef arch_kmap_local_high_get
-static inline void *arch_kmap_local_high_get(struct page *page)
-{
- return NULL;
-}
-#endif
-
-/* Unmap a local mapping which was obtained by kmap_high_get() */
-static inline bool kmap_high_unmap_local(unsigned long vaddr)
-{
-#ifdef ARCH_NEEDS_KMAP_HIGH_GET
- if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) {
- kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
- return true;
- }
-#endif
- return false;
-}
-
-static inline int kmap_local_calc_idx(int idx)
-{
- return idx + KM_MAX_IDX * smp_processor_id();
-}
-
-static pte_t *__kmap_pte;
-
-static pte_t *kmap_get_pte(void)
-{
- if (!__kmap_pte)
- __kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
- return __kmap_pte;
-}
-
-void *__kmap_local_pfn_prot(unsigned long pfn, pgprot_t prot)
-{
- pte_t pteval, *kmap_pte = kmap_get_pte();
- unsigned long vaddr;
- int idx;
-
- /*
- * Disable migration so resulting virtual address is stable
- * accross preemption.
- */
- migrate_disable();
- preempt_disable();
- idx = arch_kmap_local_map_idx(kmap_local_idx_push(), pfn);
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
- BUG_ON(!pte_none(*(kmap_pte - idx)));
- pteval = pfn_pte(pfn, prot);
- set_pte_at(&init_mm, vaddr, kmap_pte - idx, pteval);
- arch_kmap_local_post_map(vaddr, pteval);
- current->kmap_ctrl.pteval[kmap_local_idx()] = pteval;
- preempt_enable();
-
- return (void *)vaddr;
-}
-EXPORT_SYMBOL_GPL(__kmap_local_pfn_prot);
-
-void *__kmap_local_page_prot(struct page *page, pgprot_t prot)
-{
- void *kmap;
-
- if (!PageHighMem(page))
- return page_address(page);
-
- /* Try kmap_high_get() if architecture has it enabled */
- kmap = arch_kmap_local_high_get(page);
- if (kmap)
- return kmap;
-
- return __kmap_local_pfn_prot(page_to_pfn(page), prot);
-}
-EXPORT_SYMBOL(__kmap_local_page_prot);
-
-void kunmap_local_indexed(void *vaddr)
-{
- unsigned long addr = (unsigned long) vaddr & PAGE_MASK;
- pte_t *kmap_pte = kmap_get_pte();
- int idx;
-
- if (addr < __fix_to_virt(FIX_KMAP_END) ||
- addr > __fix_to_virt(FIX_KMAP_BEGIN)) {
- /*
- * Handle mappings which were obtained by kmap_high_get()
- * first as the virtual address of such mappings is below
- * PAGE_OFFSET. Warn for all other addresses which are in
- * the user space part of the virtual address space.
- */
- if (!kmap_high_unmap_local(addr))
- WARN_ON_ONCE(addr < PAGE_OFFSET);
- return;
- }
-
- preempt_disable();
- idx = arch_kmap_local_unmap_idx(kmap_local_idx(), addr);
- WARN_ON_ONCE(addr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-
- arch_kmap_local_pre_unmap(addr);
- pte_clear(&init_mm, addr, kmap_pte - idx);
- arch_kmap_local_post_unmap(addr);
- current->kmap_ctrl.pteval[kmap_local_idx()] = __pte(0);
- kmap_local_idx_pop();
- preempt_enable();
- migrate_enable();
-}
-EXPORT_SYMBOL(kunmap_local_indexed);
-
-/*
- * Invoked before switch_to(). This is safe even when during or after
- * clearing the maps an interrupt which needs a kmap_local happens because
- * the task::kmap_ctrl.idx is not modified by the unmapping code so a
- * nested kmap_local will use the next unused index and restore the index
- * on unmap. The already cleared kmaps of the outgoing task are irrelevant
- * because the interrupt context does not know about them. The same applies
- * when scheduling back in for an interrupt which happens before the
- * restore is complete.
- */
-void __kmap_local_sched_out(void)
-{
- struct task_struct *tsk = current;
- pte_t *kmap_pte = kmap_get_pte();
- int i;
-
- /* Clear kmaps */
- for (i = 0; i < tsk->kmap_ctrl.idx; i++) {
- pte_t pteval = tsk->kmap_ctrl.pteval[i];
- unsigned long addr;
- int idx;
-
- /* With debug all even slots are unmapped and act as guard */
- if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !(i & 0x01)) {
- WARN_ON_ONCE(!pte_none(pteval));
- continue;
- }
- if (WARN_ON_ONCE(pte_none(pteval)))
- continue;
-
- /*
- * This is a horrible hack for XTENSA to calculate the
- * coloured PTE index. Uses the PFN encoded into the pteval
- * and the map index calculation because the actual mapped
- * virtual address is not stored in task::kmap_ctrl.
- * For any sane architecture this is optimized out.
- */
- idx = arch_kmap_local_map_idx(i, pte_pfn(pteval));
-
- addr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
- arch_kmap_local_pre_unmap(addr);
- pte_clear(&init_mm, addr, kmap_pte - idx);
- arch_kmap_local_post_unmap(addr);
- }
-}
-
-void __kmap_local_sched_in(void)
-{
- struct task_struct *tsk = current;
- pte_t *kmap_pte = kmap_get_pte();
- int i;
-
- /* Restore kmaps */
- for (i = 0; i < tsk->kmap_ctrl.idx; i++) {
- pte_t pteval = tsk->kmap_ctrl.pteval[i];
- unsigned long addr;
- int idx;
-
- /* With debug all even slots are unmapped and act as guard */
- if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !(i & 0x01)) {
- WARN_ON_ONCE(!pte_none(pteval));
- continue;
- }
- if (WARN_ON_ONCE(pte_none(pteval)))
- continue;
-
- /* See comment in __kmap_local_sched_out() */
- idx = arch_kmap_local_map_idx(i, pte_pfn(pteval));
- addr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
- set_pte_at(&init_mm, addr, kmap_pte - idx, pteval);
- arch_kmap_local_post_map(addr, pteval);
- }
-}
-
-void kmap_local_fork(struct task_struct *tsk)
-{
- if (WARN_ON_ONCE(tsk->kmap_ctrl.idx))
- memset(&tsk->kmap_ctrl, 0, sizeof(tsk->kmap_ctrl));
-}
-
-#endif
+#endif /* CONFIG_HIGHMEM */
#if defined(HASHED_PAGE_VIRTUAL)
--
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