svn commit: r322397 - in head/sys/compat/linuxkpi/common: include/linux src

[Hans Petter Selasky]

Author: hselasky
Date: Fri Aug 11 10:44:40 2017
New Revision: 322397
URL: https://svnweb.freebsd.org/changeset/base/322397

Log:
  Make sure the "vm_flags" and "vm_page_prot" fields get set correctly
  in the VM area structure in the LinuxKPI when doing mmap() and that
  unsupported bits are masked away.
  
  While at it fix some redundant use of parenthesing inside some related
  macros.
  
  Found by:	KrishnamRaju ErapaRaju <Krishna2 at chelsio.com>
  MFC after:	1 week
  Sponsored by:	Mellanox Technologies

Modified:
  head/sys/compat/linuxkpi/common/include/linux/page.h
  head/sys/compat/linuxkpi/common/src/linux_compat.c

Modified: head/sys/compat/linuxkpi/common/include/linux/page.h
==============================================================================
--- head/sys/compat/linuxkpi/common/include/linux/page.h	Fri Aug 11 10:08:18 2017	(r322396)
+++ head/sys/compat/linuxkpi/common/include/linux/page.h	Fri Aug 11 10:44:40 2017	(r322397)
@@ -48,38 +48,36 @@ typedef unsigned long pgprot_t;
 
 #define page	vm_page
 
-#define	LINUXKPI_PROT_VALID (1 << 4)
-#define	LINUXKPI_CACHE_MODE_SHIFT 3
+#define	LINUXKPI_PROT_VALID (1 << 3)
+#define	LINUXKPI_CACHE_MODE_SHIFT 4
 
+CTASSERT((VM_PROT_ALL & -LINUXKPI_PROT_VALID) == 0);
+
 static inline pgprot_t
 cachemode2protval(vm_memattr_t attr)
 {
-	return ((attr | LINUXKPI_PROT_VALID) << LINUXKPI_CACHE_MODE_SHIFT);
+	return ((attr << LINUXKPI_CACHE_MODE_SHIFT) | LINUXKPI_PROT_VALID);
 }
 
 static inline vm_memattr_t
 pgprot2cachemode(pgprot_t prot)
 {
-	int val;
-
-	val = prot >> LINUXKPI_CACHE_MODE_SHIFT;
-
-	if (val & LINUXKPI_PROT_VALID)
-		return (val & ~LINUXKPI_PROT_VALID);
+	if (prot & LINUXKPI_PROT_VALID)
+		return (prot >> LINUXKPI_CACHE_MODE_SHIFT);
 	else
 		return (VM_MEMATTR_DEFAULT);
 }
 
-#define	virt_to_page(x)		PHYS_TO_VM_PAGE(vtophys((x)))
-#define	page_to_pfn(pp)		(VM_PAGE_TO_PHYS((pp)) >> PAGE_SHIFT)
+#define	virt_to_page(x)		PHYS_TO_VM_PAGE(vtophys(x))
+#define	page_to_pfn(pp)		(VM_PAGE_TO_PHYS(pp) >> PAGE_SHIFT)
 #define	pfn_to_page(pfn)	(PHYS_TO_VM_PAGE((pfn) << PAGE_SHIFT))
-#define	nth_page(page,n)	pfn_to_page(page_to_pfn((page)) + (n))
+#define	nth_page(page,n)	pfn_to_page(page_to_pfn(page) + (n))
 
-#define	clear_page(page)		memset((page), 0, PAGE_SIZE)
+#define	clear_page(page)		memset(page, 0, PAGE_SIZE)
 #define	pgprot_noncached(prot)		\
-	((prot) | cachemode2protval(VM_MEMATTR_UNCACHEABLE))
+	(((prot) & VM_PROT_ALL) | cachemode2protval(VM_MEMATTR_UNCACHEABLE))
 #define	pgprot_writecombine(prot)	\
-	((prot) | cachemode2protval(VM_MEMATTR_WRITE_COMBINING))
+	(((prot) & VM_PROT_ALL) | cachemode2protval(VM_MEMATTR_WRITE_COMBINING))
 
 #undef	PAGE_MASK
 #define	PAGE_MASK	(~(PAGE_SIZE-1))

Modified: head/sys/compat/linuxkpi/common/src/linux_compat.c
==============================================================================
--- head/sys/compat/linuxkpi/common/src/linux_compat.c	Fri Aug 11 10:08:18 2017	(r322396)
+++ head/sys/compat/linuxkpi/common/src/linux_compat.c	Fri Aug 11 10:44:40 2017	(r322397)
@@ -1210,7 +1210,7 @@ linux_dev_mmap_single(struct cdev *dev, vm_ooffset_t *
 	vmap->vm_end = size;
 	vmap->vm_pgoff = *offset / PAGE_SIZE;
 	vmap->vm_pfn = 0;
-	vmap->vm_flags = vmap->vm_page_prot = nprot;
+	vmap->vm_flags = vmap->vm_page_prot = (nprot & VM_PROT_ALL);
 	vmap->vm_ops = NULL;
 	vmap->vm_file = get_file(filp);
 	vmap->vm_mm = mm;