PARISC fixes on 20130213

This is a couple of patches, one to fix a broken build with HPUX compatibility
 and the other to solve a coherency problem we've been seeing in our TLB where
 setting a page read only occasionally fails to trigger a COW because of a
 stale writeable TLB entry.
 
 Signed-off-by: James Bottomley <JBottomley@Parallels.com>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.19 (GNU/Linux)
 
 iQEcBAABAgAGBQJRGx0pAAoJEDeqqVYsXL0MIZMIAMX9RTW766Umn17MG7pBv+sc
 opve+z5bBv/6Ky+o+UhnwGSHv1xPX27Nli4x65J4PhqiBB+gR+DnFtYQCSpz7cTT
 XeIObaL2FsRfOHxbVOpZhfcOdOw1JaDytUbtyQUrrTQO7RebZG1TZ4XERyCMPzVi
 UzxdX4Xk5aCwByOk158Dx+MYuwXfHY5mLWWPqQ90L+ruOKayg/QSEX1P6BXd8j4V
 18BBAwLgcGSkSyto/wvDFDCu5jra49Cfm1lE3OXmRktA2vS/W13lgVaglufmlHHk
 PeJzArClIYHZFTmeNkamNQEN0NHh/fBXQP22sPnrHjWDcp9QM3lnVidsMjZcGCc=
 =xkkh
 -----END PGP SIGNATURE-----

Merge tag 'parisc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6 into stable-3.8

PARISC fixes on 20130213

This is a couple of patches, one to fix a broken build with HPUX compatibility
and the other to solve a coherency problem we've been seeing in our TLB where
setting a page read only occasionally fails to trigger a COW because of a
stale writeable TLB entry.

Signed-off-by: James Bottomley <JBottomley@Parallels.com>

arch/parisc/hpux/fs.c

@@ -43,8 +43,7 @@ int hpux_execve(struct pt_regs *regs)
 
 	error = do_execve(filename->name,
 			  (const char __user *const __user *) regs->gr[25],
-			  (const char __user *const __user *) regs->gr[24],
+			  (const char __user *const __user *) regs->gr[24]);
-			  regs);
 
 	putname(filename);
 

arch/parisc/include/asm/pgtable.h

@@ -12,11 +12,10 @@
 
 #include <linux/bitops.h>
 #include <linux/spinlock.h>
+#include <linux/mm_types.h>
 #include <asm/processor.h>
 #include <asm/cache.h>
 
-struct vm_area_struct;
-
 /*
  * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
  * memory.  For the return value to be meaningful, ADDR must be >=
@@ -40,7 +39,14 @@ struct vm_area_struct;
         do{                                                     \
                 *(pteptr) = (pteval);                           \
         } while(0)
-#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
+
+extern void purge_tlb_entries(struct mm_struct *, unsigned long);
+
+#define set_pte_at(mm, addr, ptep, pteval)                      \
+	do {                                                    \
+		set_pte(ptep, pteval);                          \
+		purge_tlb_entries(mm, addr);                    \
+	} while (0)
 
 #endif /* !__ASSEMBLY__ */
 
@@ -466,6 +472,7 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
 		old = pte_val(*ptep);
 		new = pte_val(pte_wrprotect(__pte (old)));
 	} while (cmpxchg((unsigned long *) ptep, old, new) != old);
+	purge_tlb_entries(mm, addr);
 #else
 	pte_t old_pte = *ptep;
 	set_pte_at(mm, addr, ptep, pte_wrprotect(old_pte));

arch/parisc/kernel/cache.c

@@ -419,6 +419,24 @@ void kunmap_parisc(void *addr)
 EXPORT_SYMBOL(kunmap_parisc);
 #endif
 
+void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
+{
+	unsigned long flags;
+
+	/* Note: purge_tlb_entries can be called at startup with
+	   no context.  */
+
+	/* Disable preemption while we play with %sr1.  */
+	preempt_disable();
+	mtsp(mm->context, 1);
+	purge_tlb_start(flags);
+	pdtlb(addr);
+	pitlb(addr);
+	purge_tlb_end(flags);
+	preempt_enable();
+}
+EXPORT_SYMBOL(purge_tlb_entries);
+
 void __flush_tlb_range(unsigned long sid, unsigned long start,
 		       unsigned long end)
 {