[ARM] clearpage: provide our own clear_user_highpage()

For similar reasons as copy_user_page(), we want to avoid the
additional kmap_atomic if it's unnecessary.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

10 files changed, 100 insertions, 100 deletions

diff --git a/arch/arm/include/asm/page.h b/arch/arm/include/asm/page.h
index 1581b8cf8f33..77747df713b4 100644
--- a/arch/arm/include/asm/page.h
+++ b/arch/arm/include/asm/page.h
@@ -111,7 +111,7 @@
 struct page;
 
 struct cpu_user_fns {
-        void (*cpu_clear_user_page)(void *p, unsigned long user);
+        void (*cpu_clear_user_highpage)(struct page *page, unsigned long vaddr);
         void (*cpu_copy_user_highpage)(struct page *to, struct page *from,
                         unsigned long vaddr);
 };
@@ -119,20 +119,21 @@ struct cpu_user_fns {
 #ifdef MULTI_USER
 extern struct cpu_user_fns cpu_user;
 
-#define __cpu_clear_user_page           cpu_user.cpu_clear_user_page
+#define __cpu_clear_user_highpage       cpu_user.cpu_clear_user_highpage
 #define __cpu_copy_user_highpage        cpu_user.cpu_copy_user_highpage
 
 #else
 
-#define __cpu_clear_user_page           __glue(_USER,_clear_user_page)
+#define __cpu_clear_user_highpage       __glue(_USER,_clear_user_highpage)
 #define __cpu_copy_user_highpage        __glue(_USER,_copy_user_highpage)
 
-extern void __cpu_clear_user_page(void *p, unsigned long user);
+extern void __cpu_clear_user_highpage(struct page *page, unsigned long vaddr);
 extern void __cpu_copy_user_highpage(struct page *to, struct page *from,
                         unsigned long vaddr);
 #endif
 
-#define clear_user_page(addr,vaddr,pg)   __cpu_clear_user_page(addr, vaddr)
+#define clear_user_highpage(page,vaddr)         \
+         __cpu_clear_user_highpage(page, vaddr)
 
 #define __HAVE_ARCH_COPY_USER_HIGHPAGE
 #define copy_user_highpage(to,from,vaddr,vma)   \
diff --git a/arch/arm/mm/copypage-feroceon.c b/arch/arm/mm/copypage-feroceon.c
index edd71686b8df..c3651b2939c7 100644
--- a/arch/arm/mm/copypage-feroceon.c
+++ b/arch/arm/mm/copypage-feroceon.c
@@ -79,12 +79,11 @@ void feroceon_copy_user_highpage(struct page *to, struct page *from,
         kunmap_atomic(kto, KM_USER0);
 }
 
-void __attribute__((naked))
-feroceon_clear_user_page(void *kaddr, unsigned long vaddr)
+void feroceon_clear_user_highpage(struct page *page, unsigned long vaddr)
 {
+        void *kaddr = kmap_atomic(page, KM_USER0);
         asm("\
-        stmfd   sp!, {r4-r7, lr}                \n\
-        mov     r1, %0                          \n\
+        mov     r1, %1                          \n\
         mov     r2, #0                          \n\
         mov     r3, #0                          \n\
         mov     r4, #0                          \n\
@@ -93,19 +92,20 @@ feroceon_clear_user_page(void *kaddr, unsigned long vaddr)
         mov     r7, #0                          \n\
         mov     ip, #0                          \n\
         mov     lr, #0                          \n\
-1:      stmia   r0, {r2-r7, ip, lr}             \n\
+1:      stmia   %0, {r2-r7, ip, lr}             \n\
         subs    r1, r1, #1                      \n\
-        mcr     p15, 0, r0, c7, c14, 1          @ clean and invalidate D line\n\
+        mcr     p15, 0, %0, c7, c14, 1          @ clean and invalidate D line\n\
         add     r0, r0, #32                     \n\
         bne     1b                              \n\
-        mcr     p15, 0, r1, c7, c10, 4          @ drain WB\n\
-        ldmfd   sp!, {r4-r7, pc}"
+        mcr     p15, 0, r1, c7, c10, 4          @ drain WB"
         :
-        : "I" (PAGE_SIZE / 32));
+        : "r" (kaddr), "I" (PAGE_SIZE / 32)
+        : "r1", "r2", "r3", "r4", "r5", "r6", "r7", "ip", "lr");
+        kunmap_atomic(kaddr, KM_USER0);
 }
 
 struct cpu_user_fns feroceon_user_fns __initdata = {
-        .cpu_clear_user_page    = feroceon_clear_user_page,
+        .cpu_clear_user_highpage = feroceon_clear_user_highpage,
         .cpu_copy_user_highpage = feroceon_copy_user_highpage,
 };
 
diff --git a/arch/arm/mm/copypage-v3.c b/arch/arm/mm/copypage-v3.c
index 52df8f04d3f7..13ce0baa6ba5 100644
--- a/arch/arm/mm/copypage-v3.c
+++ b/arch/arm/mm/copypage-v3.c
@@ -54,10 +54,10 @@ void v3_copy_user_highpage(struct page *to, struct page *from,
  *
  * FIXME: do we need to handle cache stuff...
  */
-void __attribute__((naked)) v3_clear_user_page(void *kaddr, unsigned long vaddr)
+void v3_clear_user_highpage(struct page *page, unsigned long vaddr)
 {
+        void *kaddr = kmap_atomic(page, KM_USER0);
         asm("\n\
-        str     lr, [sp, #-4]!\n\
         mov     r1, %1                          @ 1\n\
         mov     r2, #0                          @ 1\n\
         mov     r3, #0                          @ 1\n\
@@ -68,13 +68,14 @@ void __attribute__((naked)) v3_clear_user_page(void *kaddr, unsigned long vaddr)
         stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
         stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
         subs    r1, r1, #1                      @ 1\n\
-        bne     1b                              @ 1\n\
-        ldr     pc, [sp], #4"
+        bne     1b                              @ 1"
         :
-        : "r" (kaddr), "I" (PAGE_SIZE / 64));
+        : "r" (kaddr), "I" (PAGE_SIZE / 64)
+        : "r1", "r2", "r3", "ip", "lr");
+        kunmap_atomic(kaddr, KM_USER0);
 }
 
 struct cpu_user_fns v3_user_fns __initdata = {
-        .cpu_clear_user_page    = v3_clear_user_page,
+        .cpu_clear_user_highpage = v3_clear_user_highpage,
         .cpu_copy_user_highpage = v3_copy_user_highpage,
 };
diff --git a/arch/arm/mm/copypage-v4mc.c b/arch/arm/mm/copypage-v4mc.c
index a7dc838fee76..a5eae503a34f 100644
--- a/arch/arm/mm/copypage-v4mc.c
+++ b/arch/arm/mm/copypage-v4mc.c
@@ -91,30 +91,30 @@ void v4_mc_copy_user_highpage(struct page *from, struct page *to,
 /*
  * ARMv4 optimised clear_user_page
  */
-void __attribute__((naked))
-v4_mc_clear_user_page(void *kaddr, unsigned long vaddr)
+void v4_mc_clear_user_highpage(struct page *page, unsigned long vaddr)
 {
-        asm volatile(
-        "str    lr, [sp, #-4]!\n\
+        void *kaddr = kmap_atomic(page, KM_USER0);
+        asm volatile("\
         mov     r1, %0                          @ 1\n\
         mov     r2, #0                          @ 1\n\
         mov     r3, #0                          @ 1\n\
         mov     ip, #0                          @ 1\n\
         mov     lr, #0                          @ 1\n\
-1:      mcr     p15, 0, r0, c7, c6, 1           @ 1   invalidate D line\n\
-        stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
-        stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
-        mcr     p15, 0, r0, c7, c6, 1           @ 1   invalidate D line\n\
-        stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
-        stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
+1:      mcr     p15, 0, %0, c7, c6, 1           @ 1   invalidate D line\n\
+        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
+        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
+        mcr     p15, 0, %0, c7, c6, 1           @ 1   invalidate D line\n\
+        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
+        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
         subs    r1, r1, #1                      @ 1\n\
-        bne     1b                              @ 1\n\
-        ldr     pc, [sp], #4"
+        bne     1b                              @ 1"
         :
-        : "I" (PAGE_SIZE / 64));
+        : "r" (kaddr), "I" (PAGE_SIZE / 64)
+        : "r1", "r2", "r3", "ip", "lr");
+        kunmap_atomic(kaddr, KM_USER0);
 }
 
 struct cpu_user_fns v4_mc_user_fns __initdata = {
-        .cpu_clear_user_page    = v4_mc_clear_user_page, 
+        .cpu_clear_user_highpage = v4_mc_clear_user_highpage,
         .cpu_copy_user_highpage = v4_mc_copy_user_highpage,
 };
diff --git a/arch/arm/mm/copypage-v4wb.c b/arch/arm/mm/copypage-v4wb.c
index 186a68a794a9..9144a96037bf 100644
--- a/arch/arm/mm/copypage-v4wb.c
+++ b/arch/arm/mm/copypage-v4wb.c
@@ -64,31 +64,31 @@ void v4wb_copy_user_highpage(struct page *to, struct page *from,
  *
  * Same story as above.
  */
-void __attribute__((naked))
-v4wb_clear_user_page(void *kaddr, unsigned long vaddr)
+void v4wb_clear_user_highpage(struct page *page, unsigned long vaddr)
 {
+        void *kaddr = kmap_atomic(page, KM_USER0);
         asm("\
-        str     lr, [sp, #-4]!\n\
-        mov     r1, %0                          @ 1\n\
+        mov     r1, %1                          @ 1\n\
         mov     r2, #0                          @ 1\n\
         mov     r3, #0                          @ 1\n\
         mov     ip, #0                          @ 1\n\
         mov     lr, #0                          @ 1\n\
-1:      mcr     p15, 0, r0, c7, c6, 1           @ 1   invalidate D line\n\
-        stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
-        stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
-        mcr     p15, 0, r0, c7, c6, 1           @ 1   invalidate D line\n\
-        stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
-        stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
+1:      mcr     p15, 0, %0, c7, c6, 1           @ 1   invalidate D line\n\
+        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
+        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
+        mcr     p15, 0, %0, c7, c6, 1           @ 1   invalidate D line\n\
+        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
+        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
         subs    r1, r1, #1                      @ 1\n\
         bne     1b                              @ 1\n\
-        mcr     p15, 0, r1, c7, c10, 4          @ 1   drain WB\n\
-        ldr     pc, [sp], #4"
+        mcr     p15, 0, r1, c7, c10, 4          @ 1   drain WB"
         :
-        : "I" (PAGE_SIZE / 64));
+        : "r" (kaddr), "I" (PAGE_SIZE / 64)
+        : "r1", "r2", "r3", "ip", "lr");
+        kunmap_atomic(kaddr, KM_USER0);
 }
 
 struct cpu_user_fns v4wb_user_fns __initdata = {
-        .cpu_clear_user_page    = v4wb_clear_user_page,
+        .cpu_clear_user_highpage = v4wb_clear_user_highpage,
         .cpu_copy_user_highpage = v4wb_copy_user_highpage,
 };
diff --git a/arch/arm/mm/copypage-v4wt.c b/arch/arm/mm/copypage-v4wt.c
index 86c2cfdbde03..b8a345d6e77e 100644
--- a/arch/arm/mm/copypage-v4wt.c
+++ b/arch/arm/mm/copypage-v4wt.c
@@ -60,29 +60,29 @@ void v4wt_copy_user_highpage(struct page *to, struct page *from,
  *
  * Same story as above.
  */
-void __attribute__((naked))
-v4wt_clear_user_page(void *kaddr, unsigned long vaddr)
+void v4wt_clear_user_highpage(struct page *page, unsigned long vaddr)
 {
+        void *kaddr = kmap_atomic(page, KM_USER0);
         asm("\
-        str     lr, [sp, #-4]!\n\
-        mov     r1, %0                          @ 1\n\
+        mov     r1, %1                          @ 1\n\
         mov     r2, #0                          @ 1\n\
         mov     r3, #0                          @ 1\n\
         mov     ip, #0                          @ 1\n\
         mov     lr, #0                          @ 1\n\
-1:      stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
-        stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
-        stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
-        stmia   r0!, {r2, r3, ip, lr}           @ 4\n\
+1:      stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
+        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
+        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
+        stmia   %0!, {r2, r3, ip, lr}           @ 4\n\
         subs    r1, r1, #1                      @ 1\n\
         bne     1b                              @ 1\n\
-        mcr     p15, 0, r2, c7, c7, 0           @ flush ID cache\n\
-        ldr     pc, [sp], #4"
+        mcr     p15, 0, r2, c7, c7, 0           @ flush ID cache"
         :
-        : "I" (PAGE_SIZE / 64));
+        : "r" (kaddr), "I" (PAGE_SIZE / 64)
+        : "r1", "r2", "r3", "ip", "lr");
+        kunmap_atomic(kaddr, KM_USER0);
 }
 
 struct cpu_user_fns v4wt_user_fns __initdata = {
-        .cpu_clear_user_page    = v4wt_clear_user_page,
+        .cpu_clear_user_highpage = v4wt_clear_user_highpage,
         .cpu_copy_user_highpage = v4wt_copy_user_highpage,
 };
diff --git a/arch/arm/mm/copypage-v6.c b/arch/arm/mm/copypage-v6.c
index 2ea75d0f5048..4127a7bddfe5 100644
--- a/arch/arm/mm/copypage-v6.c
+++ b/arch/arm/mm/copypage-v6.c
@@ -49,9 +49,11 @@ static void v6_copy_user_highpage_nonaliasing(struct page *to,
  * Clear the user page.  No aliasing to deal with so we can just
  * attack the kernel's existing mapping of this page.
  */
-static void v6_clear_user_page_nonaliasing(void *kaddr, unsigned long vaddr)
+static void v6_clear_user_highpage_nonaliasing(struct page *page, unsigned long vaddr)
 {
+        void *kaddr = kmap_atomic(page, KM_USER0);
         clear_page(kaddr);
+        kunmap_atomic(kaddr, KM_USER0);
 }
 
 /*
@@ -107,20 +109,13 @@ static void v6_copy_user_highpage_aliasing(struct page *to,
  * so remap the kernel page into the same cache colour as the user
  * page.
  */
-static void v6_clear_user_page_aliasing(void *kaddr, unsigned long vaddr)
+static void v6_clear_user_highpage_aliasing(struct page *page, unsigned long vaddr)
 {
         unsigned int offset = CACHE_COLOUR(vaddr);
         unsigned long to = to_address + (offset << PAGE_SHIFT);
 
-        /*
-         * Discard data in the kernel mapping for the new page
-         * FIXME: needs this MCRR to be supported.
-         */
-        __asm__("mcrr   p15, 0, %1, %0, c6      @ 0xec401f06"
-           :
-           : "r" (kaddr),
-             "r" ((unsigned long)kaddr + PAGE_SIZE - L1_CACHE_BYTES)
-           : "cc");
+        /* FIXME: not highmem safe */
+        discard_old_kernel_data(page_address(page));
 
         /*
          * Now clear the page using the same cache colour as
@@ -128,7 +123,7 @@ static void v6_clear_user_page_aliasing(void *kaddr, unsigned long vaddr)
          */
         spin_lock(&v6_lock);
 
-        set_pte_ext(TOP_PTE(to_address) + offset, pfn_pte(__pa(kaddr) >> PAGE_SHIFT, PAGE_KERNEL), 0);
+        set_pte_ext(TOP_PTE(to_address) + offset, pfn_pte(page_to_pfn(page), PAGE_KERNEL), 0);
         flush_tlb_kernel_page(to);
         clear_page((void *)to);
 
@@ -136,14 +131,14 @@ static void v6_clear_user_page_aliasing(void *kaddr, unsigned long vaddr)
 }
 
 struct cpu_user_fns v6_user_fns __initdata = {
-        .cpu_clear_user_page    = v6_clear_user_page_nonaliasing,
+        .cpu_clear_user_highpage = v6_clear_user_highpage_nonaliasing,
         .cpu_copy_user_highpage = v6_copy_user_highpage_nonaliasing,
 };
 
 static int __init v6_userpage_init(void)
 {
         if (cache_is_vipt_aliasing()) {
-                cpu_user.cpu_clear_user_page = v6_clear_user_page_aliasing;
+                cpu_user.cpu_clear_user_highpage = v6_clear_user_highpage_aliasing;
                 cpu_user.cpu_copy_user_highpage = v6_copy_user_highpage_aliasing;
         }
 
diff --git a/arch/arm/mm/copypage-xsc3.c b/arch/arm/mm/copypage-xsc3.c
index caa697ccd8db..0e7cb325ca4c 100644
--- a/arch/arm/mm/copypage-xsc3.c
+++ b/arch/arm/mm/copypage-xsc3.c
@@ -87,26 +87,27 @@ void xsc3_mc_copy_user_highpage(struct page *to, struct page *from,
  *  r0 = destination
  *  r1 = virtual user address of ultimate destination page
  */
-void __attribute__((naked))
-xsc3_mc_clear_user_page(void *kaddr, unsigned long vaddr)
+void xsc3_mc_clear_user_highpage(struct page *page, unsigned long vaddr)
 {
+        void *kaddr = kmap_atomic(page, KM_USER0);
         asm("\
-        mov     r1, %0                          \n\
+        mov     r1, %1                          \n\
         mov     r2, #0                          \n\
         mov     r3, #0                          \n\
-1:      mcr     p15, 0, r0, c7, c6, 1           @ invalidate line\n\
-        strd    r2, [r0], #8                    \n\
-        strd    r2, [r0], #8                    \n\
-        strd    r2, [r0], #8                    \n\
-        strd    r2, [r0], #8                    \n\
+1:      mcr     p15, 0, %0, c7, c6, 1           @ invalidate line\n\
+        strd    r2, [%0], #8                    \n\
+        strd    r2, [%0], #8                    \n\
+        strd    r2, [%0], #8                    \n\
+        strd    r2, [%0], #8                    \n\
         subs    r1, r1, #1                      \n\
-        bne     1b                              \n\
-        mov     pc, lr"
+        bne     1b"
         :
-        : "I" (PAGE_SIZE / 32));
+        : "r" (kaddr), "I" (PAGE_SIZE / 32)
+        : "r1", "r2", "r3");
+        kunmap_atomic(kaddr, KM_USER0);
 }
 
 struct cpu_user_fns xsc3_mc_user_fns __initdata = {
-        .cpu_clear_user_page    = xsc3_mc_clear_user_page,
+        .cpu_clear_user_highpage = xsc3_mc_clear_user_highpage,
         .cpu_copy_user_highpage = xsc3_mc_copy_user_highpage,
 };
diff --git a/arch/arm/mm/copypage-xscale.c b/arch/arm/mm/copypage-xscale.c
index 01bafafce181..aa9f2ff9dce0 100644
--- a/arch/arm/mm/copypage-xscale.c
+++ b/arch/arm/mm/copypage-xscale.c
@@ -113,28 +113,30 @@ void xscale_mc_copy_user_highpage(struct page *to, struct page *from,
 /*
  * XScale optimised clear_user_page
  */
-void __attribute__((naked))
-xscale_mc_clear_user_page(void *kaddr, unsigned long vaddr)
+void
+xscale_mc_clear_user_highpage(struct page *page, unsigned long vaddr)
 {
+        void *kaddr = kmap_atomic(page, KM_USER0);
         asm volatile(
-        "mov    r1, %0                          \n\
+        "mov    r1, %1                          \n\
         mov     r2, #0                          \n\
         mov     r3, #0                          \n\
-1:      mov     ip, r0                          \n\
-        strd    r2, [r0], #8                    \n\
-        strd    r2, [r0], #8                    \n\
-        strd    r2, [r0], #8                    \n\
-        strd    r2, [r0], #8                    \n\
+1:      mov     ip, %0                          \n\
+        strd    r2, [%0], #8                    \n\
+        strd    r2, [%0], #8                    \n\
+        strd    r2, [%0], #8                    \n\
+        strd    r2, [%0], #8                    \n\
         mcr     p15, 0, ip, c7, c10, 1          @ clean D line\n\
         subs    r1, r1, #1                      \n\
         mcr     p15, 0, ip, c7, c6, 1           @ invalidate D line\n\
-        bne     1b                              \n\
-        mov     pc, lr"
+        bne     1b"
         :
-        : "I" (PAGE_SIZE / 32));
+        : "r" (kaddr), "I" (PAGE_SIZE / 32)
+        : "r1", "r2", "r3", "ip");
+        kunmap_atomic(kaddr, KM_USER0);
 }
 
 struct cpu_user_fns xscale_mc_user_fns __initdata = {
-        .cpu_clear_user_page    = xscale_mc_clear_user_page, 
+        .cpu_clear_user_highpage = xscale_mc_clear_user_highpage,
         .cpu_copy_user_highpage = xscale_mc_copy_user_highpage,
 };
diff --git a/arch/arm/mm/proc-syms.c b/arch/arm/mm/proc-syms.c
index b9743e6416c4..4ad3bf291ad3 100644
--- a/arch/arm/mm/proc-syms.c
+++ b/arch/arm/mm/proc-syms.c
@@ -33,7 +33,7 @@ EXPORT_SYMBOL(cpu_cache);
 
 #ifdef CONFIG_MMU
 #ifndef MULTI_USER
-EXPORT_SYMBOL(__cpu_clear_user_page);
+EXPORT_SYMBOL(__cpu_clear_user_highpage);
 EXPORT_SYMBOL(__cpu_copy_user_highpage);
 #else
 EXPORT_SYMBOL(cpu_user);