Merge tag 'v3.6-rc7' into drm-intel-next-queued

Manual backmerge of -rc7 to resolve a silent conflict leading to
compile failure in drivers/gpu/drm/i915/intel_hdmi.c.

This is due to the bugfix in -rc7:

commit b98b60167279df3acac9422c3c9820d9ebbcf9fb
Author: Wang Xingchao <xingchao.wang@intel.com>
Date:   Thu Sep 13 07:43:22 2012 +0800

    drm/i915: HDMI - Clear Audio Enable bit for Hot Plug

Since this code moved around a lot in -next git put that snippet at
the wrong spot. I've tried to fix this by making the conflict explicit
by merging a version for next with:

commit 3cce574f0190dd149472059fb69267cf83d290f9
Author: Wang Xingchao <xingchao.wang@intel.com>
Date:   Thu Sep 13 11:19:00 2012 +0800

    drm/i915: HDMI - Clear Audio Enable bit for Hot Plug unconditionally

But that failed to solve the entire problem. To avoid pushing out
further -nightly branch to our QA where this is broken, do the
backmerge and manually add the stuff git adds to -next from the patch
in -fixes.

Note that this doesn't show up in git's merge diff (and hence is also
not handled by git rerere), which adds to the reasons why I'd like to
fix this with a verbose backmerge. The git merge diff only shows a
bunch of trivial conflicts of the "code changed in lines next to each
another" kind.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 63 insertions, 79 deletions

diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c
index 60ee2b883797..2d37bb861faf 100644
--- a/arch/s390/lib/uaccess_pt.c
+++ b/arch/s390/lib/uaccess_pt.c
@@ -2,69 +2,82 @@
  *  User access functions based on page table walks for enhanced
  *  system layout without hardware support.
  *
- *    Copyright IBM Corp. 2006
+ *    Copyright IBM Corp. 2006, 2012
  *    Author(s): Gerald Schaefer (gerald.schaefer@de.ibm.com)
  */
 
 #include <linux/errno.h>
 #include <linux/hardirq.h>
 #include <linux/mm.h>
+#include <linux/hugetlb.h>
 #include <asm/uaccess.h>
 #include <asm/futex.h>
 #include "uaccess.h"
 
-static inline pte_t *follow_table(struct mm_struct *mm, unsigned long addr)
+
+/*
+ * Returns kernel address for user virtual address. If the returned address is
+ * >= -4095 (IS_ERR_VALUE(x) returns true), a fault has occured and the address
+ * contains the (negative) exception code.
+ */
+static __always_inline unsigned long follow_table(struct mm_struct *mm,
+						  unsigned long addr, int write)
 {
 	pgd_t *pgd;
 	pud_t *pud;
 	pmd_t *pmd;
+	pte_t *ptep;
 
 	pgd = pgd_offset(mm, addr);
 	if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
-		return (pte_t *) 0x3a;
+		return -0x3aUL;
 
 	pud = pud_offset(pgd, addr);
 	if (pud_none(*pud) || unlikely(pud_bad(*pud)))
-		return (pte_t *) 0x3b;
+		return -0x3bUL;
 
 	pmd = pmd_offset(pud, addr);
-	if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
-		return (pte_t *) 0x10;
+	if (pmd_none(*pmd))
+		return -0x10UL;
+	if (pmd_huge(*pmd)) {
+		if (write && (pmd_val(*pmd) & _SEGMENT_ENTRY_RO))
+			return -0x04UL;
+		return (pmd_val(*pmd) & HPAGE_MASK) + (addr & ~HPAGE_MASK);
+	}
+	if (unlikely(pmd_bad(*pmd)))
+		return -0x10UL;
+
+	ptep = pte_offset_map(pmd, addr);
+	if (!pte_present(*ptep))
+		return -0x11UL;
+	if (write && !pte_write(*ptep))
+		return -0x04UL;
 
-	return pte_offset_map(pmd, addr);
+	return (pte_val(*ptep) & PAGE_MASK) + (addr & ~PAGE_MASK);
 }
 
 static __always_inline size_t __user_copy_pt(unsigned long uaddr, void *kptr,
 					     size_t n, int write_user)
 {
 	struct mm_struct *mm = current->mm;
-	unsigned long offset, pfn, done, size;
-	pte_t *pte;
+	unsigned long offset, done, size, kaddr;
 	void *from, *to;
 
 	done = 0;
 retry:
 	spin_lock(&mm->page_table_lock);
 	do {
-		pte = follow_table(mm, uaddr);
-		if ((unsigned long) pte < 0x1000)
+		kaddr = follow_table(mm, uaddr, write_user);
+		if (IS_ERR_VALUE(kaddr))
 			goto fault;
-		if (!pte_present(*pte)) {
-			pte = (pte_t *) 0x11;
-			goto fault;
-		} else if (write_user && !pte_write(*pte)) {
-			pte = (pte_t *) 0x04;
-			goto fault;
-		}
 
-		pfn = pte_pfn(*pte);
-		offset = uaddr & (PAGE_SIZE - 1);
+		offset = uaddr & ~PAGE_MASK;
 		size = min(n - done, PAGE_SIZE - offset);
 		if (write_user) {
-			to = (void *)((pfn << PAGE_SHIFT) + offset);
+			to = (void *) kaddr;
 			from = kptr + done;
 		} else {
-			from = (void *)((pfn << PAGE_SHIFT) + offset);
+			from = (void *) kaddr;
 			to = kptr + done;
 		}
 		memcpy(to, from, size);
@@ -75,7 +88,7 @@ retry:
 	return n - done;
 fault:
 	spin_unlock(&mm->page_table_lock);
-	if (__handle_fault(uaddr, (unsigned long) pte, write_user))
+	if (__handle_fault(uaddr, -kaddr, write_user))
 		return n - done;
 	goto retry;
 }
@@ -84,27 +97,22 @@ fault:
  * Do DAT for user address by page table walk, return kernel address.
  * This function needs to be called with current->mm->page_table_lock held.
  */
-static __always_inline unsigned long __dat_user_addr(unsigned long uaddr)
+static __always_inline unsigned long __dat_user_addr(unsigned long uaddr,
+						     int write)
 {
 	struct mm_struct *mm = current->mm;
-	unsigned long pfn;
-	pte_t *pte;
+	unsigned long kaddr;
 	int rc;
 
 retry:
-	pte = follow_table(mm, uaddr);
-	if ((unsigned long) pte < 0x1000)
-		goto fault;
-	if (!pte_present(*pte)) {
-		pte = (pte_t *) 0x11;
+	kaddr = follow_table(mm, uaddr, write);
+	if (IS_ERR_VALUE(kaddr))
 		goto fault;
-	}
 
-	pfn = pte_pfn(*pte);
-	return (pfn << PAGE_SHIFT) + (uaddr & (PAGE_SIZE - 1));
+	return kaddr;
 fault:
 	spin_unlock(&mm->page_table_lock);
-	rc = __handle_fault(uaddr, (unsigned long) pte, 0);
+	rc = __handle_fault(uaddr, -kaddr, write);
 	spin_lock(&mm->page_table_lock);
 	if (!rc)
 		goto retry;
@@ -159,11 +167,9 @@ static size_t clear_user_pt(size_t n, void __user *to)
 
 static size_t strnlen_user_pt(size_t count, const char __user *src)
 {
-	char *addr;
 	unsigned long uaddr = (unsigned long) src;
 	struct mm_struct *mm = current->mm;
-	unsigned long offset, pfn, done, len;
-	pte_t *pte;
+	unsigned long offset, done, len, kaddr;
 	size_t len_str;
 
 	if (segment_eq(get_fs(), KERNEL_DS))
@@ -172,19 +178,13 @@ static size_t strnlen_user_pt(size_t count, const char __user *src)
 retry:
 	spin_lock(&mm->page_table_lock);
 	do {
-		pte = follow_table(mm, uaddr);
-		if ((unsigned long) pte < 0x1000)
-			goto fault;
-		if (!pte_present(*pte)) {
-			pte = (pte_t *) 0x11;
+		kaddr = follow_table(mm, uaddr, 0);
+		if (IS_ERR_VALUE(kaddr))
 			goto fault;
-		}
 
-		pfn = pte_pfn(*pte);
-		offset = uaddr & (PAGE_SIZE-1);
-		addr = (char *)(pfn << PAGE_SHIFT) + offset;
+		offset = uaddr & ~PAGE_MASK;
 		len = min(count - done, PAGE_SIZE - offset);
-		len_str = strnlen(addr, len);
+		len_str = strnlen((char *) kaddr, len);
 		done += len_str;
 		uaddr += len_str;
 	} while ((len_str == len) && (done < count));
@@ -192,7 +192,7 @@ retry:
 	return done + 1;
 fault:
 	spin_unlock(&mm->page_table_lock);
-	if (__handle_fault(uaddr, (unsigned long) pte, 0))
+	if (__handle_fault(uaddr, -kaddr, 0))
 		return 0;
 	goto retry;
 }
@@ -225,11 +225,10 @@ static size_t copy_in_user_pt(size_t n, void __user *to,
 			      const void __user *from)
 {
 	struct mm_struct *mm = current->mm;
-	unsigned long offset_from, offset_to, offset_max, pfn_from, pfn_to,
-		      uaddr, done, size, error_code;
+	unsigned long offset_max, uaddr, done, size, error_code;
 	unsigned long uaddr_from = (unsigned long) from;
 	unsigned long uaddr_to = (unsigned long) to;
-	pte_t *pte_from, *pte_to;
+	unsigned long kaddr_to, kaddr_from;
 	int write_user;
 
 	if (segment_eq(get_fs(), KERNEL_DS)) {
@@ -242,38 +241,23 @@ retry:
 	do {
 		write_user = 0;
 		uaddr = uaddr_from;
-		pte_from = follow_table(mm, uaddr_from);
-		error_code = (unsigned long) pte_from;
-		if (error_code < 0x1000)
-			goto fault;
-		if (!pte_present(*pte_from)) {
-			error_code = 0x11;
+		kaddr_from = follow_table(mm, uaddr_from, 0);
+		error_code = kaddr_from;
+		if (IS_ERR_VALUE(error_code))
 			goto fault;
-		}
 
 		write_user = 1;
 		uaddr = uaddr_to;
-		pte_to = follow_table(mm, uaddr_to);
-		error_code = (unsigned long) pte_to;
-		if (error_code < 0x1000)
-			goto fault;
-		if (!pte_present(*pte_to)) {
-			error_code = 0x11;
+		kaddr_to = follow_table(mm, uaddr_to, 1);
+		error_code = (unsigned long) kaddr_to;
+		if (IS_ERR_VALUE(error_code))
 			goto fault;
-		} else if (!pte_write(*pte_to)) {
-			error_code = 0x04;
-			goto fault;
-		}
 
-		pfn_from = pte_pfn(*pte_from);
-		pfn_to = pte_pfn(*pte_to);
-		offset_from = uaddr_from & (PAGE_SIZE-1);
-		offset_to = uaddr_from & (PAGE_SIZE-1);
-		offset_max = max(offset_from, offset_to);
+		offset_max = max(uaddr_from & ~PAGE_MASK,
+				 uaddr_to & ~PAGE_MASK);
 		size = min(n - done, PAGE_SIZE - offset_max);
 
-		memcpy((void *)(pfn_to << PAGE_SHIFT) + offset_to,
-		       (void *)(pfn_from << PAGE_SHIFT) + offset_from, size);
+		memcpy((void *) kaddr_to, (void *) kaddr_from, size);
 		done += size;
 		uaddr_from += size;
 		uaddr_to += size;
@@ -282,7 +266,7 @@ retry:
 	return n - done;
 fault:
 	spin_unlock(&mm->page_table_lock);
-	if (__handle_fault(uaddr, error_code, write_user))
+	if (__handle_fault(uaddr, -error_code, write_user))
 		return n - done;
 	goto retry;
 }
@@ -341,7 +325,7 @@ int futex_atomic_op_pt(int op, u32 __user *uaddr, int oparg, int *old)
 		return __futex_atomic_op_pt(op, uaddr, oparg, old);
 	spin_lock(&current->mm->page_table_lock);
 	uaddr = (u32 __force __user *)
-		__dat_user_addr((__force unsigned long) uaddr);
+		__dat_user_addr((__force unsigned long) uaddr, 1);
 	if (!uaddr) {
 		spin_unlock(&current->mm->page_table_lock);
 		return -EFAULT;
@@ -378,7 +362,7 @@ int futex_atomic_cmpxchg_pt(u32 *uval, u32 __user *uaddr,
 		return __futex_atomic_cmpxchg_pt(uval, uaddr, oldval, newval);
 	spin_lock(&current->mm->page_table_lock);
 	uaddr = (u32 __force __user *)
-		__dat_user_addr((__force unsigned long) uaddr);
+		__dat_user_addr((__force unsigned long) uaddr, 1);
 	if (!uaddr) {
 		spin_unlock(&current->mm->page_table_lock);
 		return -EFAULT;