x86: cpa: move flush to cpa

The set_memory_* and set_pages_* family of API's currently requires the
callers to do a global tlb flush after the function call; forgetting this is
a very nasty deathtrap. This patch moves the global tlb flush into
each of the callers

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

4 files changed, 71 insertions, 92 deletions

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index f7b941c3b2c3..0d3369b900e9 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -752,15 +752,11 @@ void mark_rodata_ro(void)
 		printk("Write protecting the kernel text: %luk\n", size >> 10);
 
 #ifdef CONFIG_CPA_DEBUG
-		global_flush_tlb();
-
 		printk("Testing CPA: Reverting %lx-%lx\n", start, start+size);
 		set_pages_rw(virt_to_page(start), size>>PAGE_SHIFT);
-		global_flush_tlb();
 
 		printk("Testing CPA: write protecting again\n");
 		set_pages_ro(virt_to_page(start), size>>PAGE_SHIFT);
-		global_flush_tlb();
 #endif
 	}
 #endif
@@ -770,22 +766,12 @@ void mark_rodata_ro(void)
 	printk("Write protecting the kernel read-only data: %luk\n",
 	       size >> 10);
 
-	/*
-	 * set_pages_*() requires a global_flush_tlb() call after it.
-	 * We do this after the printk so that if something went wrong in the
-	 * change, the printk gets out at least to give a better debug hint
-	 * of who is the culprit.
-	 */
-	global_flush_tlb();
-
 #ifdef CONFIG_CPA_DEBUG
 	printk("Testing CPA: undo %lx-%lx\n", start, start + size);
 	set_pages_rw(virt_to_page(start), size >> PAGE_SHIFT);
-	global_flush_tlb();
 
 	printk("Testing CPA: write protecting again\n");
 	set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
-	global_flush_tlb();
 #endif
 }
 #endif
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 4757be7b5e55..9b69fa54a831 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -610,22 +610,12 @@ void mark_rodata_ro(void)
 	printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
 	       (end - start) >> 10);
 
-	/*
-	 * set_memory_*() requires a global_flush_tlb() call after it.
-	 * We do this after the printk so that if something went wrong in the
-	 * change, the printk gets out at least to give a better debug hint
-	 * of who is the culprit.
-	 */
-	global_flush_tlb();
-
 #ifdef CONFIG_CPA_DEBUG
 	printk("Testing CPA: undo %lx-%lx\n", start, end);
 	set_memory_rw(start, (end-start) >> PAGE_SHIFT);
-	global_flush_tlb();
 
 	printk("Testing CPA: again\n");
 	set_memory_ro(start, (end-start) >> PAGE_SHIFT);
-	global_flush_tlb();
 #endif
 }
 #endif
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index b86f66fa5185..6a9a1418bc98 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -96,8 +96,6 @@ static int ioremap_change_attr(unsigned long paddr, unsigned long size,
 		err = set_memory_wb(vaddr, nrpages);
 		break;
 	}
-	if (!err)
-		global_flush_tlb();
 
 	return err;
 }
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index e4d2b6930e61..a2d747c06147 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -23,6 +23,36 @@ within(unsigned long addr, unsigned long start, unsigned long end)
 }
 
 /*
+ * Flushing functions
+ */
+void clflush_cache_range(void *addr, int size)
+{
+	int i;
+
+	for (i = 0; i < size; i += boot_cpu_data.x86_clflush_size)
+		clflush(addr+i);
+}
+
+static void flush_kernel_map(void *arg)
+{
+	/*
+	 * Flush all to work around Errata in early athlons regarding
+	 * large page flushing.
+	 */
+	__flush_tlb_all();
+
+	if (boot_cpu_data.x86_model >= 4)
+		wbinvd();
+}
+
+static void global_flush_tlb(void)
+{
+	BUG_ON(irqs_disabled());
+
+	on_each_cpu(flush_kernel_map, NULL, 1, 1);
+}
+
+/*
  * Certain areas of memory on x86 require very specific protection flags,
  * for example the BIOS area or kernel text. Callers don't always get this
  * right (again, ioremap() on BIOS memory is not uncommon) so this function
@@ -328,149 +358,124 @@ static int change_page_attr_clear(unsigned long addr, int numpages,
 
 int set_memory_uc(unsigned long addr, int numpages)
 {
-	pgprot_t uncached;
+	int err;
 
-	pgprot_val(uncached) = _PAGE_PCD | _PAGE_PWT;
-	return change_page_attr_set(addr, numpages, uncached);
+	err = change_page_attr_set(addr, numpages,
+				__pgprot(_PAGE_PCD | _PAGE_PWT));
+	global_flush_tlb();
+	return err;
 }
 EXPORT_SYMBOL(set_memory_uc);
 
 int set_memory_wb(unsigned long addr, int numpages)
 {
-	pgprot_t uncached;
+	int err;
 
-	pgprot_val(uncached) = _PAGE_PCD | _PAGE_PWT;
-	return change_page_attr_clear(addr, numpages, uncached);
+	err = change_page_attr_clear(addr, numpages,
+				__pgprot(_PAGE_PCD | _PAGE_PWT));
+	global_flush_tlb();
+	return err;
 }
 EXPORT_SYMBOL(set_memory_wb);
 
 int set_memory_x(unsigned long addr, int numpages)
 {
-	pgprot_t nx;
+	int err;
 
-	pgprot_val(nx) = _PAGE_NX;
-	return change_page_attr_clear(addr, numpages, nx);
+	err = change_page_attr_clear(addr, numpages,
+				__pgprot(_PAGE_NX));
+	global_flush_tlb();
+	return err;
 }
 EXPORT_SYMBOL(set_memory_x);
 
 int set_memory_nx(unsigned long addr, int numpages)
 {
-	pgprot_t nx;
+	int err;
 
-	pgprot_val(nx) = _PAGE_NX;
-	return change_page_attr_set(addr, numpages, nx);
+	err = change_page_attr_set(addr, numpages,
+				__pgprot(_PAGE_NX));
+	global_flush_tlb();
+	return err;
 }
 EXPORT_SYMBOL(set_memory_nx);
 
 int set_memory_ro(unsigned long addr, int numpages)
 {
-	pgprot_t rw;
+	int err;
 
-	pgprot_val(rw) = _PAGE_RW;
-	return change_page_attr_clear(addr, numpages, rw);
+	err = change_page_attr_clear(addr, numpages,
+				__pgprot(_PAGE_RW));
+	global_flush_tlb();
+	return err;
 }
 
 int set_memory_rw(unsigned long addr, int numpages)
 {
-	pgprot_t rw;
+	int err;
 
-	pgprot_val(rw) = _PAGE_RW;
-	return change_page_attr_set(addr, numpages, rw);
+	err = change_page_attr_set(addr, numpages,
+				__pgprot(_PAGE_RW));
+	global_flush_tlb();
+	return err;
 }
 
 int set_memory_np(unsigned long addr, int numpages)
 {
-	pgprot_t present;
+	int err;
 
-	pgprot_val(present) = _PAGE_PRESENT;
-	return change_page_attr_clear(addr, numpages, present);
+	err = change_page_attr_clear(addr, numpages,
+				__pgprot(_PAGE_PRESENT));
+	global_flush_tlb();
+	return err;
 }
 
 int set_pages_uc(struct page *page, int numpages)
 {
 	unsigned long addr = (unsigned long)page_address(page);
-	pgprot_t uncached;
 
-	pgprot_val(uncached) = _PAGE_PCD | _PAGE_PWT;
-	return change_page_attr_set(addr, numpages, uncached);
+	return set_memory_uc(addr, numpages);
 }
 EXPORT_SYMBOL(set_pages_uc);
 
 int set_pages_wb(struct page *page, int numpages)
 {
 	unsigned long addr = (unsigned long)page_address(page);
-	pgprot_t uncached;
 
-	pgprot_val(uncached) = _PAGE_PCD | _PAGE_PWT;
-	return change_page_attr_clear(addr, numpages, uncached);
+	return set_memory_wb(addr, numpages);
 }
 EXPORT_SYMBOL(set_pages_wb);
 
 int set_pages_x(struct page *page, int numpages)
 {
 	unsigned long addr = (unsigned long)page_address(page);
-	pgprot_t nx;
 
-	pgprot_val(nx) = _PAGE_NX;
-	return change_page_attr_clear(addr, numpages, nx);
+	return set_memory_x(addr, numpages);
 }
 EXPORT_SYMBOL(set_pages_x);
 
 int set_pages_nx(struct page *page, int numpages)
 {
 	unsigned long addr = (unsigned long)page_address(page);
-	pgprot_t nx;
 
-	pgprot_val(nx) = _PAGE_NX;
-	return change_page_attr_set(addr, numpages, nx);
+	return set_memory_nx(addr, numpages);
 }
 EXPORT_SYMBOL(set_pages_nx);
 
 int set_pages_ro(struct page *page, int numpages)
 {
 	unsigned long addr = (unsigned long)page_address(page);
-	pgprot_t rw;
 
-	pgprot_val(rw) = _PAGE_RW;
-	return change_page_attr_clear(addr, numpages, rw);
+	return set_memory_ro(addr, numpages);
 }
 
 int set_pages_rw(struct page *page, int numpages)
 {
 	unsigned long addr = (unsigned long)page_address(page);
-	pgprot_t rw;
-
-	pgprot_val(rw) = _PAGE_RW;
-	return change_page_attr_set(addr, numpages, rw);
-}
-
-void clflush_cache_range(void *addr, int size)
-{
-	int i;
-
-	for (i = 0; i < size; i += boot_cpu_data.x86_clflush_size)
-		clflush(addr+i);
-}
 
-static void flush_kernel_map(void *arg)
-{
-	/*
-	 * Flush all to work around Errata in early athlons regarding
-	 * large page flushing.
-	 */
-	__flush_tlb_all();
-
-	if (boot_cpu_data.x86_model >= 4)
-		wbinvd();
+	return set_memory_rw(addr, numpages);
 }
 
-void global_flush_tlb(void)
-{
-	BUG_ON(irqs_disabled());
-
-	on_each_cpu(flush_kernel_map, NULL, 1, 1);
-}
-EXPORT_SYMBOL(global_flush_tlb);
 
 #ifdef CONFIG_DEBUG_PAGEALLOC