Merge tag 'xtensa-20140830' of git://github.com/czankel/xtensa-linux

Pull Xtensa updates from Chris Zankel:
 "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
     unrecoverabl exception)
   - replace termios IOCTL code definitions with constants (userspace
     build breakage)"

* tag 'xtensa-20140830' of git://github.com/czankel/xtensa-linux: (25 commits)
  xtensa: deprecate fast_xtensa and fast_spill_registers syscalls
  xtensa: don't allow overflow/underflow on unaligned stack
  xtensa: fix a6 and a7 handling in fast_syscall_xtensa
  xtensa: allow single-stepping through unaligned load/store
  xtensa: move invalid unaligned instruction handler closer to its users
  xtensa: make fast_unaligned store restartable
  xtensa: add double exception fixup handler for fast_unaligned
  xtensa: fix kernel/user jump out of fast_unaligned
  xtensa: configure kc705 for highmem
  xtensa: support highmem in aliasing cache flushing code
  xtensa: support aliasing cache in kmap
  xtensa: support aliasing cache in k[un]map_atomic
  xtensa: implement clear_user_highpage and copy_user_highpage
  xtensa: fix TLBTEMP_BASE_2 region handling in fast_second_level_miss
  xtensa: allow fixmap and kmap span more than one page table
  xtensa: make fixmap region addressing grow with index
  xtensa: fix access to THREAD_RA/THREAD_SP/THREAD_DS
  xtensa: add renameat2 syscall
  xtensa: fix address checks in dma_{alloc,free}_coherent
  xtensa: replace IOCTL code definitions with constants
  ...

1 files changed, 26 insertions, 4 deletions

diff --git a/arch/xtensa/include/asm/fixmap.h b/arch/xtensa/include/asm/fixmap.h
index 9f6c33d0428..62b507deea9 100644
--- a/arch/xtensa/include/asm/fixmap.h
+++ b/arch/xtensa/include/asm/fixmap.h
@@ -23,8 +23,8 @@
  * Here we define all the compile-time 'special' virtual
  * addresses. The point is to have a constant address at
  * compile time, but to set the physical address only
- * in the boot process. We allocate these special  addresses
- * from the end of the consistent memory region backwards.
+ * in the boot process. We allocate these special addresses
+ * from the start of the consistent memory region upwards.
  * Also this lets us do fail-safe vmalloc(), we
  * can guarantee that these special addresses and
  * vmalloc()-ed addresses never overlap.
@@ -38,7 +38,8 @@ enum fixed_addresses {
 #ifdef CONFIG_HIGHMEM
 	/* reserved pte's for temporary kernel mappings */
 	FIX_KMAP_BEGIN,
-	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
+	FIX_KMAP_END = FIX_KMAP_BEGIN +
+		(KM_TYPE_NR * NR_CPUS * DCACHE_N_COLORS) - 1,
 #endif
 	__end_of_fixed_addresses
 };
@@ -47,7 +48,28 @@ enum fixed_addresses {
 #define FIXADDR_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)
 #define FIXADDR_START	((FIXADDR_TOP - FIXADDR_SIZE) & PMD_MASK)
 
-#include <asm-generic/fixmap.h>
+#define __fix_to_virt(x)	(FIXADDR_START + ((x) << PAGE_SHIFT))
+#define __virt_to_fix(x)	(((x) - FIXADDR_START) >> PAGE_SHIFT)
+
+#ifndef __ASSEMBLY__
+/*
+ * 'index to address' translation. If anyone tries to use the idx
+ * directly without translation, we catch the bug with a NULL-deference
+ * kernel oops. Illegal ranges of incoming indices are caught too.
+ */
+static __always_inline unsigned long fix_to_virt(const unsigned int idx)
+{
+	BUILD_BUG_ON(idx >= __end_of_fixed_addresses);
+	return __fix_to_virt(idx);
+}
+
+static inline unsigned long virt_to_fix(const unsigned long vaddr)
+{
+	BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START);
+	return __virt_to_fix(vaddr);
+}
+
+#endif
 
 #define kmap_get_fixmap_pte(vaddr) \
 	pte_offset_kernel( \