xtensa: implement clear_user_highpage and copy_user_highpage
Existing clear_user_page and copy_user_page cannot be used with highmem
because they calculate physical page address from its virtual address
and do it incorrectly in case of high memory page mapped with
kmap_atomic. Also kmap is not needed, as most likely userspace mapping
color would be different from the kmapped color.
Provide clear_user_highpage and copy_user_highpage functions that
determine if temporary mapping is needed for the pages. Move most of the
logic of the former clear_user_page and copy_user_page to
xtensa/mm/cache.c only leaving temporary mapping setup, invalidation and
clearing/copying in the xtensa/mm/misc.S. Rename these functions to
clear_page_alias and copy_page_alias.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
diff --git a/arch/xtensa/mm/misc.S b/arch/xtensa/mm/misc.S
index 1f68558..11a01c3 100644
--- a/arch/xtensa/mm/misc.S
+++ b/arch/xtensa/mm/misc.S
@@ -110,41 +110,24 @@
#if (DCACHE_WAY_SIZE > PAGE_SIZE)
/*
- * clear_user_page (void *addr, unsigned long vaddr, struct page *page)
- * a2 a3 a4
+ * clear_page_alias(void *addr, unsigned long paddr)
+ * a2 a3
*/
-ENTRY(clear_user_page)
+ENTRY(clear_page_alias)
entry a1, 32
- /* Mark page dirty and determine alias. */
+ /* Skip setting up a temporary DTLB if not aliased low page. */
- movi a7, (1 << PG_ARCH_1)
- l32i a5, a4, PAGE_FLAGS
- xor a6, a2, a3
- extui a3, a3, PAGE_SHIFT, DCACHE_ALIAS_ORDER
- extui a6, a6, PAGE_SHIFT, DCACHE_ALIAS_ORDER
- or a5, a5, a7
- slli a3, a3, PAGE_SHIFT
- s32i a5, a4, PAGE_FLAGS
+ movi a5, PAGE_OFFSET
+ movi a6, 0
+ beqz a3, 1f
- /* Skip setting up a temporary DTLB if not aliased. */
+ /* Setup a temporary DTLB for the addr. */
- beqz a6, 1f
-
- /* Invalidate kernel page. */
-
- mov a10, a2
- call8 __invalidate_dcache_page
-
- /* Setup a temporary DTLB with the color of the VPN */
-
- movi a4, ((PAGE_KERNEL | _PAGE_HW_WRITE) - PAGE_OFFSET) & 0xffffffff
- movi a5, TLBTEMP_BASE_1 # virt
- add a6, a2, a4 # ppn
- add a2, a5, a3 # add 'color'
-
+ addi a6, a3, (PAGE_KERNEL | _PAGE_HW_WRITE)
+ mov a4, a2
wdtlb a6, a2
dsync
@@ -165,62 +148,43 @@
/* We need to invalidate the temporary idtlb entry, if any. */
-1: addi a2, a2, -PAGE_SIZE
- idtlb a2
+1: idtlb a4
dsync
retw
-ENDPROC(clear_user_page)
+ENDPROC(clear_page_alias)
/*
- * copy_page_user (void *to, void *from, unsigned long vaddr, struct page *page)
- * a2 a3 a4 a5
+ * copy_page_alias(void *to, void *from,
+ * a2 a3
+ * unsigned long to_paddr, unsigned long from_paddr)
+ * a4 a5
*/
-ENTRY(copy_user_page)
+ENTRY(copy_page_alias)
entry a1, 32
- /* Mark page dirty and determine alias for destination. */
+ /* Skip setting up a temporary DTLB for destination if not aliased. */
- movi a8, (1 << PG_ARCH_1)
- l32i a9, a5, PAGE_FLAGS
- xor a6, a2, a4
- xor a7, a3, a4
- extui a4, a4, PAGE_SHIFT, DCACHE_ALIAS_ORDER
- extui a6, a6, PAGE_SHIFT, DCACHE_ALIAS_ORDER
- extui a7, a7, PAGE_SHIFT, DCACHE_ALIAS_ORDER
- or a9, a9, a8
- slli a4, a4, PAGE_SHIFT
- s32i a9, a5, PAGE_FLAGS
- movi a5, ((PAGE_KERNEL | _PAGE_HW_WRITE) - PAGE_OFFSET) & 0xffffffff
+ movi a6, 0
+ movi a7, 0
+ beqz a4, 1f
- beqz a6, 1f
+ /* Setup a temporary DTLB for destination. */
- /* Invalidate dcache */
-
- mov a10, a2
- call8 __invalidate_dcache_page
-
- /* Setup a temporary DTLB with a matching color. */
-
- movi a8, TLBTEMP_BASE_1 # base
- add a6, a2, a5 # ppn
- add a2, a8, a4 # add 'color'
-
+ addi a6, a4, (PAGE_KERNEL | _PAGE_HW_WRITE)
wdtlb a6, a2
dsync
- /* Skip setting up a temporary DTLB for destination if not aliased. */
+ /* Skip setting up a temporary DTLB for source if not aliased. */
-1: beqz a7, 1f
+1: beqz a5, 1f
- /* Setup a temporary DTLB with a matching color. */
+ /* Setup a temporary DTLB for source. */
- movi a8, TLBTEMP_BASE_2 # base
- add a7, a3, a5 # ppn
- add a3, a8, a4
+ addi a7, a5, PAGE_KERNEL
addi a8, a3, 1 # way1
wdtlb a7, a8
@@ -271,7 +235,7 @@
retw
-ENDPROC(copy_user_page)
+ENDPROC(copy_page_alias)
#endif
@@ -300,6 +264,30 @@
retw
ENDPROC(__flush_invalidate_dcache_page_alias)
+
+/*
+ * void __invalidate_dcache_page_alias (addr, phys)
+ * a2 a3
+ */
+
+ENTRY(__invalidate_dcache_page_alias)
+
+ entry sp, 16
+
+ movi a7, 0 # required for exception handler
+ addi a6, a3, (PAGE_KERNEL | _PAGE_HW_WRITE)
+ mov a4, a2
+ wdtlb a6, a2
+ dsync
+
+ ___invalidate_dcache_page a2 a3
+
+ idtlb a4
+ dsync
+
+ retw
+
+ENDPROC(__invalidate_dcache_page_alias)
#endif
ENTRY(__tlbtemp_mapping_itlb)