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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:38 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:38 +0000
commit08b74a000942a380fe028845f92cd3a0dee827d5 (patch)
treeaa78b4e12607c3e1fcce8d5cc42df4330792f118 /debian/patches-rt/0218-arm-Enable-highmem-for-rt.patch
parentAdding upstream version 4.19.249. (diff)
downloadlinux-08b74a000942a380fe028845f92cd3a0dee827d5.tar.xz
linux-08b74a000942a380fe028845f92cd3a0dee827d5.zip
Adding debian version 4.19.249-2.debian/4.19.249-2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'debian/patches-rt/0218-arm-Enable-highmem-for-rt.patch')
-rw-r--r--debian/patches-rt/0218-arm-Enable-highmem-for-rt.patch184
1 files changed, 184 insertions, 0 deletions
diff --git a/debian/patches-rt/0218-arm-Enable-highmem-for-rt.patch b/debian/patches-rt/0218-arm-Enable-highmem-for-rt.patch
new file mode 100644
index 000000000..6d37c0670
--- /dev/null
+++ b/debian/patches-rt/0218-arm-Enable-highmem-for-rt.patch
@@ -0,0 +1,184 @@
+From d8647f71379a704607e15bb3a7fd5d84b3f10a6d Mon Sep 17 00:00:00 2001
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Wed, 13 Feb 2013 11:03:11 +0100
+Subject: [PATCH 218/347] arm: Enable highmem for rt
+Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz
+
+fixup highmem for ARM.
+
+Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
+---
+ arch/arm/include/asm/switch_to.h | 8 +++++
+ arch/arm/mm/highmem.c | 56 +++++++++++++++++++++++++++-----
+ include/linux/highmem.h | 1 +
+ 3 files changed, 57 insertions(+), 8 deletions(-)
+
+diff --git a/arch/arm/include/asm/switch_to.h b/arch/arm/include/asm/switch_to.h
+index d3e937dcee4d..6ab96a2ce1f8 100644
+--- a/arch/arm/include/asm/switch_to.h
++++ b/arch/arm/include/asm/switch_to.h
+@@ -4,6 +4,13 @@
+
+ #include <linux/thread_info.h>
+
++#if defined CONFIG_PREEMPT_RT_FULL && defined CONFIG_HIGHMEM
++void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p);
++#else
++static inline void
++switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { }
++#endif
++
+ /*
+ * For v7 SMP cores running a preemptible kernel we may be pre-empted
+ * during a TLB maintenance operation, so execute an inner-shareable dsb
+@@ -26,6 +33,7 @@ extern struct task_struct *__switch_to(struct task_struct *, struct thread_info
+ #define switch_to(prev,next,last) \
+ do { \
+ __complete_pending_tlbi(); \
++ switch_kmaps(prev, next); \
+ last = __switch_to(prev,task_thread_info(prev), task_thread_info(next)); \
+ } while (0)
+
+diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
+index eb4b225d28c9..542692dbd40a 100644
+--- a/arch/arm/mm/highmem.c
++++ b/arch/arm/mm/highmem.c
+@@ -34,6 +34,11 @@ static inline pte_t get_fixmap_pte(unsigned long vaddr)
+ return *ptep;
+ }
+
++static unsigned int fixmap_idx(int type)
++{
++ return FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++}
++
+ void *kmap(struct page *page)
+ {
+ might_sleep();
+@@ -54,12 +59,13 @@ EXPORT_SYMBOL(kunmap);
+
+ void *kmap_atomic(struct page *page)
+ {
++ pte_t pte = mk_pte(page, kmap_prot);
+ unsigned int idx;
+ unsigned long vaddr;
+ void *kmap;
+ int type;
+
+- preempt_disable();
++ preempt_disable_nort();
+ pagefault_disable();
+ if (!PageHighMem(page))
+ return page_address(page);
+@@ -79,7 +85,7 @@ void *kmap_atomic(struct page *page)
+
+ type = kmap_atomic_idx_push();
+
+- idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++ idx = fixmap_idx(type);
+ vaddr = __fix_to_virt(idx);
+ #ifdef CONFIG_DEBUG_HIGHMEM
+ /*
+@@ -93,7 +99,10 @@ void *kmap_atomic(struct page *page)
+ * in place, so the contained TLB flush ensures the TLB is updated
+ * with the new mapping.
+ */
+- set_fixmap_pte(idx, mk_pte(page, kmap_prot));
++#ifdef CONFIG_PREEMPT_RT_FULL
++ current->kmap_pte[type] = pte;
++#endif
++ set_fixmap_pte(idx, pte);
+
+ return (void *)vaddr;
+ }
+@@ -106,10 +115,13 @@ void __kunmap_atomic(void *kvaddr)
+
+ if (kvaddr >= (void *)FIXADDR_START) {
+ type = kmap_atomic_idx();
+- idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++ idx = fixmap_idx(type);
+
+ if (cache_is_vivt())
+ __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
++#ifdef CONFIG_PREEMPT_RT_FULL
++ current->kmap_pte[type] = __pte(0);
++#endif
+ #ifdef CONFIG_DEBUG_HIGHMEM
+ BUG_ON(vaddr != __fix_to_virt(idx));
+ #else
+@@ -122,28 +134,56 @@ void __kunmap_atomic(void *kvaddr)
+ kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
+ }
+ pagefault_enable();
+- preempt_enable();
++ preempt_enable_nort();
+ }
+ EXPORT_SYMBOL(__kunmap_atomic);
+
+ void *kmap_atomic_pfn(unsigned long pfn)
+ {
++ pte_t pte = pfn_pte(pfn, kmap_prot);
+ unsigned long vaddr;
+ int idx, type;
+ struct page *page = pfn_to_page(pfn);
+
+- preempt_disable();
++ preempt_disable_nort();
+ pagefault_disable();
+ if (!PageHighMem(page))
+ return page_address(page);
+
+ type = kmap_atomic_idx_push();
+- idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id();
++ idx = fixmap_idx(type);
+ vaddr = __fix_to_virt(idx);
+ #ifdef CONFIG_DEBUG_HIGHMEM
+ BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
+ #endif
+- set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot));
++#ifdef CONFIG_PREEMPT_RT_FULL
++ current->kmap_pte[type] = pte;
++#endif
++ set_fixmap_pte(idx, pte);
+
+ return (void *)vaddr;
+ }
++#if defined CONFIG_PREEMPT_RT_FULL
++void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p)
++{
++ int i;
++
++ /*
++ * Clear @prev's kmap_atomic mappings
++ */
++ for (i = 0; i < prev_p->kmap_idx; i++) {
++ int idx = fixmap_idx(i);
++
++ set_fixmap_pte(idx, __pte(0));
++ }
++ /*
++ * Restore @next_p's kmap_atomic mappings
++ */
++ for (i = 0; i < next_p->kmap_idx; i++) {
++ int idx = fixmap_idx(i);
++
++ if (!pte_none(next_p->kmap_pte[i]))
++ set_fixmap_pte(idx, next_p->kmap_pte[i]);
++ }
++}
++#endif
+diff --git a/include/linux/highmem.h b/include/linux/highmem.h
+index 1ac89e4718bf..eaa2ef9bc10e 100644
+--- a/include/linux/highmem.h
++++ b/include/linux/highmem.h
+@@ -8,6 +8,7 @@
+ #include <linux/mm.h>
+ #include <linux/uaccess.h>
+ #include <linux/hardirq.h>
++#include <linux/sched.h>
+
+ #include <asm/cacheflush.h>
+
+--
+2.36.1
+