Merge tag 'xtensa-for-next-20140815' into for_next

Xtensa improvements for 3.17:
- support highmem on cores with aliasing data cache. Enable highmem on kc705
  by default;
- simplify addition of new core variants (no need to modify Kconfig /
  Makefiles);
- improve robustness of unaligned access handler and its interaction with
  window overflow/underflow exception handlers;
- deprecate atomic and spill registers syscalls;
- clean up Kconfig: remove orphan MATH_EMULATION, sort 'select' statements;
- wire up renameat2 syscall.

Various fixes:
- fix address checks in dma_{alloc,free}_coherent (runtime BUG);
- fix access to THREAD_RA/THREAD_SP/THREAD_DS (debug build breakage);
- fix TLBTEMP_BASE_2 region handling in fast_second_level_miss (runtime
  unrecoverable exception);
- fix a6 and a7 handling in fast_syscall_xtensa (runtime userspace register
  clobbering);
- fix kernel/user jump out of fast_unaligned (potential runtime unrecoverable
  exception);
- replace termios IOCTL code definitions with constants (userspace build
  breakage).

Signed-off-by: Chris Zankel <chris@zankel.net>

1 files changed, 22 insertions, 16 deletions

diff --git a/arch/xtensa/mm/mmu.c b/arch/xtensa/mm/mmu.c
index 3429b483d9f8..abe4513eb0dd 100644
--- a/arch/xtensa/mm/mmu.c
+++ b/arch/xtensa/mm/mmu.c
@@ -18,32 +18,38 @@
 #include <asm/io.h>
 
 #if defined(CONFIG_HIGHMEM)
-static void * __init init_pmd(unsigned long vaddr)
+static void * __init init_pmd(unsigned long vaddr, unsigned long n_pages)
 {
 	pgd_t *pgd = pgd_offset_k(vaddr);
 	pmd_t *pmd = pmd_offset(pgd, vaddr);
+	pte_t *pte;
+	unsigned long i;
 
-	if (pmd_none(*pmd)) {
-		unsigned i;
-		pte_t *pte = alloc_bootmem_low_pages(PAGE_SIZE);
+	n_pages = ALIGN(n_pages, PTRS_PER_PTE);
 
-		for (i = 0; i < 1024; i++)
-			pte_clear(NULL, 0, pte + i);
+	pr_debug("%s: vaddr: 0x%08lx, n_pages: %ld\n",
+		 __func__, vaddr, n_pages);
 
-		set_pmd(pmd, __pmd(((unsigned long)pte) & PAGE_MASK));
-		BUG_ON(pte != pte_offset_kernel(pmd, 0));
-		pr_debug("%s: vaddr: 0x%08lx, pmd: 0x%p, pte: 0x%p\n",
-			 __func__, vaddr, pmd, pte);
-		return pte;
-	} else {
-		return pte_offset_kernel(pmd, 0);
+	pte = alloc_bootmem_low_pages(n_pages * sizeof(pte_t));
+
+	for (i = 0; i < n_pages; ++i)
+		pte_clear(NULL, 0, pte + i);
+
+	for (i = 0; i < n_pages; i += PTRS_PER_PTE, ++pmd) {
+		pte_t *cur_pte = pte + i;
+
+		BUG_ON(!pmd_none(*pmd));
+		set_pmd(pmd, __pmd(((unsigned long)cur_pte) & PAGE_MASK));
+		BUG_ON(cur_pte != pte_offset_kernel(pmd, 0));
+		pr_debug("%s: pmd: 0x%p, pte: 0x%p\n",
+			 __func__, pmd, cur_pte);
 	}
+	return pte;
 }
 
 static void __init fixedrange_init(void)
 {
-	BUILD_BUG_ON(FIXADDR_SIZE > PMD_SIZE);
-	init_pmd(__fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK);
+	init_pmd(__fix_to_virt(0), __end_of_fixed_addresses);
 }
 #endif
 
@@ -52,7 +58,7 @@ void __init paging_init(void)
 	memset(swapper_pg_dir, 0, PAGE_SIZE);
 #ifdef CONFIG_HIGHMEM
 	fixedrange_init();
-	pkmap_page_table = init_pmd(PKMAP_BASE);
+	pkmap_page_table = init_pmd(PKMAP_BASE, LAST_PKMAP);
 	kmap_init();
 #endif
 }