fs: allow per-device dax status checking for filesystems

commit ba23cba9b3bdc967aabdc6ff1e3e9b11ce05bb4f upstream.

Change bdev_dax_supported so it takes a bdev parameter.  This enables
multi-device filesystems like xfs to check that a dax device can work for
the particular filesystem.  Once that's in place, actually fix all the
parts of XFS where we need to be able to distinguish between datadev and
rtdev.

This patch fixes the problem where we screw up the dax support checking
in xfs if the datadev and rtdev have different dax capabilities.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
[rez: Re-added __bdev_dax_supported() for !CONFIG_FS_DAX cases]
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index c4cd034a382053fd931579a88343fe0830280582..8d54021cd2f6df2e8b3eacc2994d110c4697dc56 100644 (file)
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -73,7 +73,7 @@ EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev);
 
 /**
  * __bdev_dax_supported() - Check if the device supports dax for filesystem
- * @sb: The superblock of the device
+ * @bdev: block device to check
  * @blocksize: The block size of the device
  *
  * This is a library function for filesystems to check if the block device
@@ -81,33 +81,33 @@ EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev);
  *
  * Return: negative errno if unsupported, 0 if supported.
  */
-int __bdev_dax_supported(struct super_block *sb, int blocksize)
+int __bdev_dax_supported(struct block_device *bdev, int blocksize)
 {
-       struct block_device *bdev = sb->s_bdev;
        struct dax_device *dax_dev;
        pgoff_t pgoff;
        int err, id;
        void *kaddr;
        pfn_t pfn;
        long len;
+       char buf[BDEVNAME_SIZE];
 
        if (blocksize != PAGE_SIZE) {
-               pr_err("VFS (%s): error: unsupported blocksize for dax\n",
-                               sb->s_id);
+               pr_debug("%s: error: unsupported blocksize for dax\n",
+                               bdevname(bdev, buf));
                return -EINVAL;
        }
 
        err = bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff);
        if (err) {
-               pr_err("VFS (%s): error: unaligned partition for dax\n",
-                               sb->s_id);
+               pr_debug("%s: error: unaligned partition for dax\n",
+                               bdevname(bdev, buf));
                return err;
        }
 
        dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
        if (!dax_dev) {
-               pr_err("VFS (%s): error: device does not support dax\n",
-                               sb->s_id);
+               pr_debug("%s: error: device does not support dax\n",
+                               bdevname(bdev, buf));
                return -EOPNOTSUPP;
        }
 
@@ -118,8 +118,8 @@ int __bdev_dax_supported(struct super_block *sb, int blocksize)
        put_dax(dax_dev);
 
        if (len < 1) {
-               pr_err("VFS (%s): error: dax access failed (%ld)",
-                               sb->s_id, len);
+               pr_debug("%s: error: dax access failed (%ld)\n",
+                               bdevname(bdev, buf), len);
                return len < 0 ? len : -EIO;
        }
 

diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 1458706bd2ec6ac5ed9c0acb6c150d661bd14595..e85c57eb27345dbf4d609db1657bcfc4b92085bd 100644 (file)
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -953,7 +953,7 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
        blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
 
        if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
-               err = bdev_dax_supported(sb, blocksize);
+               err = bdev_dax_supported(sb->s_bdev, blocksize);
                if (err)
                        goto failed_mount;
        }

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 83ba37be4702aa530e39435b2faa3d21007c318b..3289ec862192e4a3b7735dcd8ed6b83cecfb7dc8 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3770,7 +3770,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
                                        " that may contain inline data");
                        goto failed_mount;
                }
-               err = bdev_dax_supported(sb, blocksize);
+               err = bdev_dax_supported(sb->s_bdev, blocksize);
                if (err)
                        goto failed_mount;
        }

diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index aa75389be8cfa81d06695f80701c2093b65289b0..682b6946d06aeba9dfec2103b8baf2e9ab51b5db 100644 (file)
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1101,7 +1101,8 @@ xfs_ioctl_setattr_dax_invalidate(
        if (fa->fsx_xflags & FS_XFLAG_DAX) {
                if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
                        return -EINVAL;
-               if (bdev_dax_supported(sb, sb->s_blocksize) < 0)
+               if (bdev_dax_supported(xfs_find_bdev_for_inode(VFS_I(ip)),
+                               sb->s_blocksize) < 0)
                        return -EINVAL;
        }
 

diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index f24e5b6cfc867af82ec8684e8d6a379d5a0facbb..1daa965f1e08a5a1f7458ca2e17b7991f60b8ad1 100644 (file)
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -1184,6 +1184,30 @@ static const struct inode_operations xfs_inline_symlink_inode_operations = {
        .update_time            = xfs_vn_update_time,
 };
 
+/* Figure out if this file actually supports DAX. */
+static bool
+xfs_inode_supports_dax(
+       struct xfs_inode        *ip)
+{
+       struct xfs_mount        *mp = ip->i_mount;
+
+       /* Only supported on non-reflinked files. */
+       if (!S_ISREG(VFS_I(ip)->i_mode) || xfs_is_reflink_inode(ip))
+               return false;
+
+       /* DAX mount option or DAX iflag must be set. */
+       if (!(mp->m_flags & XFS_MOUNT_DAX) &&
+           !(ip->i_d.di_flags2 & XFS_DIFLAG2_DAX))
+               return false;
+
+       /* Block size must match page size */
+       if (mp->m_sb.sb_blocksize != PAGE_SIZE)
+               return false;
+
+       /* Device has to support DAX too. */
+       return xfs_find_daxdev_for_inode(VFS_I(ip)) != NULL;
+}
+
 STATIC void
 xfs_diflags_to_iflags(
        struct inode            *inode,
@@ -1202,11 +1226,7 @@ xfs_diflags_to_iflags(
                inode->i_flags |= S_SYNC;
        if (flags & XFS_DIFLAG_NOATIME)
                inode->i_flags |= S_NOATIME;
-       if (S_ISREG(inode->i_mode) &&
-           ip->i_mount->m_sb.sb_blocksize == PAGE_SIZE &&
-           !xfs_is_reflink_inode(ip) &&
-           (ip->i_mount->m_flags & XFS_MOUNT_DAX ||
-            ip->i_d.di_flags2 & XFS_DIFLAG2_DAX))
+       if (xfs_inode_supports_dax(ip))
                inode->i_flags |= S_DAX;
 }
 

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index f663022353c0d98b681e51fe8578096d0fbf57bf..89f3e54e57f5b1ed19d7a4339a61c00dca645533 100644 (file)
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1640,11 +1640,17 @@ xfs_fs_fill_super(
                sb->s_flags |= SB_I_VERSION;
 
        if (mp->m_flags & XFS_MOUNT_DAX) {
+               int     error2 = 0;
+
                xfs_warn(mp,
                "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
 
-               error = bdev_dax_supported(sb, sb->s_blocksize);
-               if (error) {
+               error = bdev_dax_supported(mp->m_ddev_targp->bt_bdev,
+                               sb->s_blocksize);
+               if (mp->m_rtdev_targp)
+                       error2 = bdev_dax_supported(mp->m_rtdev_targp->bt_bdev,
+                                       sb->s_blocksize);
+               if (error && error2) {
                        xfs_alert(mp,
                        "DAX unsupported by block device. Turning off DAX.");
                        mp->m_flags &= ~XFS_MOUNT_DAX;

diff --git a/include/linux/dax.h b/include/linux/dax.h
index 895e16fcc62d50e34813d6fbd214832c9e9d305f..7b37727ad3ed959b2c54b58533d9b6bb39227c8e 100644 (file)
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -40,10 +40,10 @@ static inline void put_dax(struct dax_device *dax_dev)
 
 int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
 #if IS_ENABLED(CONFIG_FS_DAX)
-int __bdev_dax_supported(struct super_block *sb, int blocksize);
-static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
+int __bdev_dax_supported(struct block_device *bdev, int blocksize);
+static inline int bdev_dax_supported(struct block_device *bdev, int blocksize)
 {
-       return __bdev_dax_supported(sb, blocksize);
+       return __bdev_dax_supported(bdev, blocksize);
 }
 
 static inline struct dax_device *fs_dax_get_by_host(const char *host)
@@ -58,7 +58,8 @@ static inline void fs_put_dax(struct dax_device *dax_dev)
 
 struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev);
 #else
-static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
+static inline int bdev_dax_supported(struct block_device *bdev,
+               int blocksize)
 {
        return -EOPNOTSUPP;
 }