blockdev: don't set S_DAX for misaligned partitions

[linux-2.6-block.git] / fs / block_dev.c

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 33b813e04f7921e390c9f4edec0908d4fcb9337f..073bb57adab10ce14e55205eddf0e3de5862be1d 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -28,6 +28,7 @@
 #include <linux/namei.h>
 #include <linux/log2.h>
 #include <linux/cleancache.h>
+#include <linux/dax.h>
 #include <asm/uaccess.h>
 #include "internal.h"
 
@@ -441,7 +442,7 @@ EXPORT_SYMBOL_GPL(bdev_write_page);
  * accessible at this address.
  */
 long bdev_direct_access(struct block_device *bdev, sector_t sector,
-                       void **addr, unsigned long *pfn, long size)
+                       void __pmem **addr, unsigned long *pfn, long size)
 {
        long avail;
        const struct block_device_operations *ops = bdev->bd_disk->fops;
@@ -462,7 +463,7 @@ long bdev_direct_access(struct block_device *bdev, sector_t sector,
        sector += get_start_sect(bdev);
        if (sector % (PAGE_SIZE / 512))
                return -EINVAL;
-       avail = ops->direct_access(bdev, sector, addr, pfn, size);
+       avail = ops->direct_access(bdev, sector, addr, pfn);
        if (!avail)
                return -ERANGE;
        return min(avail, size);
@@ -1241,6 +1242,13 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                                goto out_clear;
                        }
                        bd_set_size(bdev, (loff_t)bdev->bd_part->nr_sects << 9);
+                       /*
+                        * If the partition is not aligned on a page
+                        * boundary, we can't do dax I/O to it.
+                        */
+                       if ((bdev->bd_part->start_sect % (PAGE_SIZE / 512)) ||
+                           (bdev->bd_part->nr_sects % (PAGE_SIZE / 512)))
+                               bdev->bd_inode->i_flags &= ~S_DAX;
                }
        } else {
                if (bdev->bd_contains == bdev) {