From 7901fd602af54133d0d39cb7ff09537e9defbace Mon Sep 17 00:00:00 2001
From: Ross Zwisler <ross.zwisler@linux.intel.com>
Date: Wed, 6 Sep 2017 16:18:58 -0700
Subject: [PATCH] dax: use PG_PMD_COLOUR instead of open coding
Git-commit: 917f34526c4123ccd93e4373719c645c85020a5a
Patch-Mainline: v4.14-rc1
References: FATE#323721
Use ~PG_PMD_COLOUR in dax_entry_waitqueue() instead of open coding an
equivalent page offset mask.
Link: http://lkml.kernel.org/r/20170822222436.18926-2-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: "Slusarz, Marcin" <marcin.slusarz@intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Hannes Reinecke <hare@suse.com>
---
fs/dax.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index 742c13e..ce9e52e 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -43,6 +43,9 @@
#define DAX_WAIT_TABLE_BITS 12
#define DAX_WAIT_TABLE_ENTRIES (1 << DAX_WAIT_TABLE_BITS)
+/* The 'colour' (ie low bits) within a PMD of a page offset. */
+#define PG_PMD_COLOUR ((PMD_SIZE >> PAGE_SHIFT) - 1)
+
static wait_queue_head_t wait_table[DAX_WAIT_TABLE_ENTRIES];
static int __init init_dax_wait_table(void)
@@ -99,7 +102,7 @@ static wait_queue_head_t *dax_entry_waitqueue(struct address_space *mapping,
* the range covered by the PMD map to the same bit lock.
*/
if (dax_is_pmd_entry(entry))
- index &= ~((1UL << (PMD_SHIFT - PAGE_SHIFT)) - 1);
+ index &= ~PG_PMD_COLOUR;
key->mapping = mapping;
key->entry_start = index;
@@ -1175,12 +1178,6 @@ static int dax_iomap_pte_fault(struct vm_fault *vmf,
}
#ifdef CONFIG_FS_DAX_PMD
-/*
- * The 'colour' (ie low bits) within a PMD of a page offset. This comes up
- * more often than one might expect in the below functions.
- */
-#define PG_PMD_COLOUR ((PMD_SIZE >> PAGE_SHIFT) - 1)
-
static int dax_pmd_insert_mapping(struct vm_fault *vmf, struct iomap *iomap,
loff_t pos, void *entry)
{
--
1.8.5.6