[PATCH v3] parisc: Fix invalidate/flush vmap routines

From: John David Anglin <dave.anglin@bell.net>
To: linux-parisc@vger.kernel.org
Cc: Helge Deller <deller@gmx.de>, Deller <deller@kernel.org>,
	James Bottomley <James.Bottomley@hansenpartnership.com>
Subject: [PATCH v3] parisc: Fix invalidate/flush vmap routines
Date: Sat, 19 Mar 2022 19:04:15 +0000	[thread overview]
Message-ID: <YjYpL/67UBzHGhuB@mx3210.localdomain> (raw)

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Cache move-in for virtual accesses is controlled by the TLB.  Thus,
we must generally purge TLB entries before flushing.  The flush routines
must use TLB entries that inhibit cache move-in.

V2: Load physical address prior to flushing TLB.  In flush_cache_page,
flush TLB when flushing and purging.

V3: Don't flush when start equals end.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
---

diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c
index 231cebb3fc0d..c7da11a278b5 100644
--- a/arch/parisc/kernel/cache.c
+++ b/arch/parisc/kernel/cache.c
@@ -607,8 +607,8 @@ void
 flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned long pfn)
 {
 	if (pfn_valid(pfn)) {
+		flush_tlb_page(vma, vmaddr);
 		if (likely(vma->vm_mm->context.space_id)) {
-			flush_tlb_page(vma, vmaddr);
 			__flush_cache_page(vma, vmaddr, PFN_PHYS(pfn));
 		} else {
 			__purge_cache_page(vma, vmaddr, PFN_PHYS(pfn));
@@ -620,6 +620,7 @@ void flush_kernel_vmap_range(void *vaddr, int size)
 {
 	unsigned long start = (unsigned long)vaddr;
 	unsigned long end = start + size;
+	unsigned long flags, physaddr;
 
 	if ((!IS_ENABLED(CONFIG_SMP) || !arch_irqs_disabled()) &&
 	    (unsigned long)size >= parisc_cache_flush_threshold) {
@@ -628,8 +629,14 @@ void flush_kernel_vmap_range(void *vaddr, int size)
 		return;
 	}
 
-	flush_kernel_dcache_range_asm(start, end);
-	flush_tlb_kernel_range(start, end);
+	while (start < end) {
+		physaddr = lpa(start);
+		purge_tlb_start(flags);
+		pdtlb(SR_KERNEL, start);
+		purge_tlb_end(flags);
+		flush_dcache_page_asm(physaddr, start);
+		start += PAGE_SIZE;
+	}
 }
 EXPORT_SYMBOL(flush_kernel_vmap_range);
 
@@ -637,6 +644,7 @@ void invalidate_kernel_vmap_range(void *vaddr, int size)
 {
 	unsigned long start = (unsigned long)vaddr;
 	unsigned long end = start + size;
+	unsigned long flags, physaddr;
 
 	if ((!IS_ENABLED(CONFIG_SMP) || !arch_irqs_disabled()) &&
 	    (unsigned long)size >= parisc_cache_flush_threshold) {
@@ -645,7 +653,13 @@ void invalidate_kernel_vmap_range(void *vaddr, int size)
 		return;
 	}
 
-	purge_kernel_dcache_range_asm(start, end);
-	flush_tlb_kernel_range(start, end);
+	while (start < end) {
+		physaddr = lpa(start);
+		purge_tlb_start(flags);
+		pdtlb(SR_KERNEL, start);
+		purge_tlb_end(flags);
+		purge_dcache_page_asm(physaddr, start);
+		start += PAGE_SIZE;
+	}
 }
 EXPORT_SYMBOL(invalidate_kernel_vmap_range);

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