diff mbox series

[V8,05/11] fs/xfs: Make DAX mount option a tri-state

Message ID 20200415064523.2244712-6-ira.weiny@intel.com (mailing list archive)
State New, archived
Headers show
Series Enable per-file/per-directory DAX operations V8 | expand

Commit Message

Ira Weiny April 15, 2020, 6:45 a.m. UTC 
From: Ira Weiny <ira.weiny@intel.com>

As agreed upon[1].  We make the dax mount option a tri-state.  '-o dax'
continues to operate the same.  We add 'always', 'never', and 'inode'
(default).

[1] https://lore.kernel.org/lkml/20200405061945.GA94792@iweiny-DESK2.sc.intel.com/

Signed-off-by: Ira Weiny <ira.weiny@intel.com>

---
Changes from v7:
	Change to XFS_MOUNT_DAX_NEVER

Changes from v6:
	Use 2 flag bits rather than a field.
	change iflag to inode

Changes from v5:
	New Patch
---
 fs/xfs/xfs_mount.h |  3 ++-
 fs/xfs/xfs_super.c | 44 ++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 42 insertions(+), 5 deletions(-)

Comments

Darrick J. Wong April 15, 2020, 3:16 p.m. UTC | #1 
On Tue, Apr 14, 2020 at 11:45:17PM -0700, ira.weiny@intel.com wrote:
> From: Ira Weiny <ira.weiny@intel.com>
> 
> As agreed upon[1].  We make the dax mount option a tri-state.  '-o dax'
> continues to operate the same.  We add 'always', 'never', and 'inode'
> (default).
> 
> [1] https://lore.kernel.org/lkml/20200405061945.GA94792@iweiny-DESK2.sc.intel.com/
> 
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> 
> ---
> Changes from v7:
> 	Change to XFS_MOUNT_DAX_NEVER
> 
> Changes from v6:
> 	Use 2 flag bits rather than a field.
> 	change iflag to inode
> 
> Changes from v5:
> 	New Patch
> ---
>  fs/xfs/xfs_mount.h |  3 ++-
>  fs/xfs/xfs_super.c | 44 ++++++++++++++++++++++++++++++++++++++++----
>  2 files changed, 42 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
> index 54bd74088936..2e88c30642e3 100644
> --- a/fs/xfs/xfs_mount.h
> +++ b/fs/xfs/xfs_mount.h
> @@ -233,7 +233,8 @@ typedef struct xfs_mount {
>  						   allocator */
>  #define XFS_MOUNT_NOATTR2	(1ULL << 25)	/* disable use of attr2 format */
>  
> -#define XFS_MOUNT_DAX_ALWAYS	(1ULL << 62)	/* TEST ONLY! */
> +#define XFS_MOUNT_DAX_ALWAYS	(1ULL << 62)
> +#define XFS_MOUNT_DAX_NEVER	(1ULL << 63)
>  
>  /*
>   * Max and min values for mount-option defined I/O
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index 3863f41757d2..142e5d03566f 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -47,6 +47,32 @@ static struct kset *xfs_kset;		/* top-level xfs sysfs dir */
>  static struct xfs_kobj xfs_dbg_kobj;	/* global debug sysfs attrs */
>  #endif
>  
> +enum {

enum xfs_dax_mode {  for the reasons given below?

> +	XFS_DAX_INODE = 0,
> +	XFS_DAX_ALWAYS = 1,
> +	XFS_DAX_NEVER = 2,
> +};
> +
> +static void xfs_mount_set_dax_mode(struct xfs_mount *mp, u32 val)

xfs style, please:

static void
xfs_mount_set_dax_mode(
	struct xfs_mount	*mp,
	u32			val)

or if you give a name to the enum above, you can enforce some type
safety too:

	enum xfs_dax_mode	val)

> +{
> +	if (val == XFS_DAX_INODE) {

and this probably could have been a "switch (val) {", in which case if
the enum ever gets expanded then gcc will whine about missing switch
cases.

The rest of the patch looks good.

--D

> +		mp->m_flags &= ~(XFS_MOUNT_DAX_ALWAYS | XFS_MOUNT_DAX_NEVER);
> +	} else if (val == XFS_DAX_ALWAYS) {
> +		mp->m_flags |= XFS_MOUNT_DAX_ALWAYS;
> +		mp->m_flags &= ~XFS_MOUNT_DAX_NEVER;
> +	} else if (val == XFS_DAX_NEVER) {
> +		mp->m_flags |= XFS_MOUNT_DAX_NEVER;
> +		mp->m_flags &= ~XFS_MOUNT_DAX_ALWAYS;
> +	}
> +}
> +
> +static const struct constant_table dax_param_enums[] = {
> +	{"inode",	XFS_DAX_INODE },
> +	{"always",	XFS_DAX_ALWAYS },
> +	{"never",	XFS_DAX_NEVER },
> +	{}
> +};
> +
>  /*
>   * Table driven mount option parser.
>   */
> @@ -59,7 +85,7 @@ enum {
>  	Opt_filestreams, Opt_quota, Opt_noquota, Opt_usrquota, Opt_grpquota,
>  	Opt_prjquota, Opt_uquota, Opt_gquota, Opt_pquota,
>  	Opt_uqnoenforce, Opt_gqnoenforce, Opt_pqnoenforce, Opt_qnoenforce,
> -	Opt_discard, Opt_nodiscard, Opt_dax,
> +	Opt_discard, Opt_nodiscard, Opt_dax, Opt_dax_enum,
>  };
>  
>  static const struct fs_parameter_spec xfs_fs_parameters[] = {
> @@ -103,6 +129,7 @@ static const struct fs_parameter_spec xfs_fs_parameters[] = {
>  	fsparam_flag("discard",		Opt_discard),
>  	fsparam_flag("nodiscard",	Opt_nodiscard),
>  	fsparam_flag("dax",		Opt_dax),
> +	fsparam_enum("dax",		Opt_dax_enum, dax_param_enums),
>  	{}
>  };
>  
> @@ -129,7 +156,6 @@ xfs_fs_show_options(
>  		{ XFS_MOUNT_GRPID,		",grpid" },
>  		{ XFS_MOUNT_DISCARD,		",discard" },
>  		{ XFS_MOUNT_LARGEIO,		",largeio" },
> -		{ XFS_MOUNT_DAX_ALWAYS,		",dax" },
>  		{ 0, NULL }
>  	};
>  	struct xfs_mount	*mp = XFS_M(root->d_sb);
> @@ -185,6 +211,13 @@ xfs_fs_show_options(
>  	if (!(mp->m_qflags & XFS_ALL_QUOTA_ACCT))
>  		seq_puts(m, ",noquota");
>  
> +	if (mp->m_flags & XFS_MOUNT_DAX_ALWAYS)
> +		seq_puts(m, ",dax=always");
> +	else if (mp->m_flags & XFS_MOUNT_DAX_NEVER)
> +		seq_puts(m, ",dax=never");
> +	else
> +		seq_puts(m, ",dax=inode");
> +
>  	return 0;
>  }
>  
> @@ -1244,7 +1277,10 @@ xfs_fc_parse_param(
>  		return 0;
>  #ifdef CONFIG_FS_DAX
>  	case Opt_dax:
> -		mp->m_flags |= XFS_MOUNT_DAX_ALWAYS;
> +		xfs_mount_set_dax_mode(mp, XFS_DAX_ALWAYS);
> +		return 0;
> +	case Opt_dax_enum:
> +		xfs_mount_set_dax_mode(mp, result.uint_32);
>  		return 0;
>  #endif
>  	default:
> @@ -1451,7 +1487,7 @@ xfs_fc_fill_super(
>  		if (!rtdev_is_dax && !datadev_is_dax) {
>  			xfs_alert(mp,
>  			"DAX unsupported by block device. Turning off DAX.");
> -			mp->m_flags &= ~XFS_MOUNT_DAX_ALWAYS;
> +			xfs_mount_set_dax_mode(mp, XFS_DAX_NEVER);
>  		}
>  		if (xfs_sb_version_hasreflink(&mp->m_sb)) {
>  			xfs_alert(mp,
> -- 
> 2.25.1
>
Ira Weiny April 16, 2020, 4:15 a.m. UTC | #2 
On Wed, Apr 15, 2020 at 08:16:13AM -0700, Darrick J. Wong wrote:
> On Tue, Apr 14, 2020 at 11:45:17PM -0700, ira.weiny@intel.com wrote:
> > From: Ira Weiny <ira.weiny@intel.com>
> > 
> > As agreed upon[1].  We make the dax mount option a tri-state.  '-o dax'
> > continues to operate the same.  We add 'always', 'never', and 'inode'
> > (default).
> > 
> > [1] https://lore.kernel.org/lkml/20200405061945.GA94792@iweiny-DESK2.sc.intel.com/
> > 
> > Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> > 
> > ---
> > Changes from v7:
> > 	Change to XFS_MOUNT_DAX_NEVER
> > 
> > Changes from v6:
> > 	Use 2 flag bits rather than a field.
> > 	change iflag to inode
> > 
> > Changes from v5:
> > 	New Patch
> > ---
> >  fs/xfs/xfs_mount.h |  3 ++-
> >  fs/xfs/xfs_super.c | 44 ++++++++++++++++++++++++++++++++++++++++----
> >  2 files changed, 42 insertions(+), 5 deletions(-)
> > 
> > diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
> > index 54bd74088936..2e88c30642e3 100644
> > --- a/fs/xfs/xfs_mount.h
> > +++ b/fs/xfs/xfs_mount.h
> > @@ -233,7 +233,8 @@ typedef struct xfs_mount {
> >  						   allocator */
> >  #define XFS_MOUNT_NOATTR2	(1ULL << 25)	/* disable use of attr2 format */
> >  
> > -#define XFS_MOUNT_DAX_ALWAYS	(1ULL << 62)	/* TEST ONLY! */
> > +#define XFS_MOUNT_DAX_ALWAYS	(1ULL << 62)
> > +#define XFS_MOUNT_DAX_NEVER	(1ULL << 63)
> >  
> >  /*
> >   * Max and min values for mount-option defined I/O
> > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> > index 3863f41757d2..142e5d03566f 100644
> > --- a/fs/xfs/xfs_super.c
> > +++ b/fs/xfs/xfs_super.c
> > @@ -47,6 +47,32 @@ static struct kset *xfs_kset;		/* top-level xfs sysfs dir */
> >  static struct xfs_kobj xfs_dbg_kobj;	/* global debug sysfs attrs */
> >  #endif
> >  
> > +enum {
> 
> enum xfs_dax_mode {  for the reasons given below?
> 
> > +	XFS_DAX_INODE = 0,
> > +	XFS_DAX_ALWAYS = 1,
> > +	XFS_DAX_NEVER = 2,
> > +};
> > +
> > +static void xfs_mount_set_dax_mode(struct xfs_mount *mp, u32 val)
> 
> xfs style, please:
> 
> static void
> xfs_mount_set_dax_mode(
> 	struct xfs_mount	*mp,
> 	u32			val)

NP changed.

> 
> or if you give a name to the enum above, you can enforce some type
> safety too:
> 
> 	enum xfs_dax_mode	val)

The problem is that the option parsing returns result.uint_32 type.  Generally
I agree with using more specific types but here I'm not sure it matters.

> 
> > +{
> > +	if (val == XFS_DAX_INODE) {
> 
> and this probably could have been a "switch (val) {", in which case if
> the enum ever gets expanded then gcc will whine about missing switch
> cases.

Sure...  that does require the enum to be defined and used in the signature...

Ok I'll use the enum!  :-D

done.

Thanks,
Ira


> 
> The rest of the patch looks good.
> 
> --D
> 
> > +		mp->m_flags &= ~(XFS_MOUNT_DAX_ALWAYS | XFS_MOUNT_DAX_NEVER);
> > +	} else if (val == XFS_DAX_ALWAYS) {
> > +		mp->m_flags |= XFS_MOUNT_DAX_ALWAYS;
> > +		mp->m_flags &= ~XFS_MOUNT_DAX_NEVER;
> > +	} else if (val == XFS_DAX_NEVER) {
> > +		mp->m_flags |= XFS_MOUNT_DAX_NEVER;
> > +		mp->m_flags &= ~XFS_MOUNT_DAX_ALWAYS;
> > +	}
> > +}
> > +
> > +static const struct constant_table dax_param_enums[] = {
> > +	{"inode",	XFS_DAX_INODE },
> > +	{"always",	XFS_DAX_ALWAYS },
> > +	{"never",	XFS_DAX_NEVER },
> > +	{}
> > +};
> > +
> >  /*
> >   * Table driven mount option parser.
> >   */
> > @@ -59,7 +85,7 @@ enum {
> >  	Opt_filestreams, Opt_quota, Opt_noquota, Opt_usrquota, Opt_grpquota,
> >  	Opt_prjquota, Opt_uquota, Opt_gquota, Opt_pquota,
> >  	Opt_uqnoenforce, Opt_gqnoenforce, Opt_pqnoenforce, Opt_qnoenforce,
> > -	Opt_discard, Opt_nodiscard, Opt_dax,
> > +	Opt_discard, Opt_nodiscard, Opt_dax, Opt_dax_enum,
> >  };
> >  
> >  static const struct fs_parameter_spec xfs_fs_parameters[] = {
> > @@ -103,6 +129,7 @@ static const struct fs_parameter_spec xfs_fs_parameters[] = {
> >  	fsparam_flag("discard",		Opt_discard),
> >  	fsparam_flag("nodiscard",	Opt_nodiscard),
> >  	fsparam_flag("dax",		Opt_dax),
> > +	fsparam_enum("dax",		Opt_dax_enum, dax_param_enums),
> >  	{}
> >  };
> >  
> > @@ -129,7 +156,6 @@ xfs_fs_show_options(
> >  		{ XFS_MOUNT_GRPID,		",grpid" },
> >  		{ XFS_MOUNT_DISCARD,		",discard" },
> >  		{ XFS_MOUNT_LARGEIO,		",largeio" },
> > -		{ XFS_MOUNT_DAX_ALWAYS,		",dax" },
> >  		{ 0, NULL }
> >  	};
> >  	struct xfs_mount	*mp = XFS_M(root->d_sb);
> > @@ -185,6 +211,13 @@ xfs_fs_show_options(
> >  	if (!(mp->m_qflags & XFS_ALL_QUOTA_ACCT))
> >  		seq_puts(m, ",noquota");
> >  
> > +	if (mp->m_flags & XFS_MOUNT_DAX_ALWAYS)
> > +		seq_puts(m, ",dax=always");
> > +	else if (mp->m_flags & XFS_MOUNT_DAX_NEVER)
> > +		seq_puts(m, ",dax=never");
> > +	else
> > +		seq_puts(m, ",dax=inode");
> > +
> >  	return 0;
> >  }
> >  
> > @@ -1244,7 +1277,10 @@ xfs_fc_parse_param(
> >  		return 0;
> >  #ifdef CONFIG_FS_DAX
> >  	case Opt_dax:
> > -		mp->m_flags |= XFS_MOUNT_DAX_ALWAYS;
> > +		xfs_mount_set_dax_mode(mp, XFS_DAX_ALWAYS);
> > +		return 0;
> > +	case Opt_dax_enum:
> > +		xfs_mount_set_dax_mode(mp, result.uint_32);
> >  		return 0;
> >  #endif
> >  	default:
> > @@ -1451,7 +1487,7 @@ xfs_fc_fill_super(
> >  		if (!rtdev_is_dax && !datadev_is_dax) {
> >  			xfs_alert(mp,
> >  			"DAX unsupported by block device. Turning off DAX.");
> > -			mp->m_flags &= ~XFS_MOUNT_DAX_ALWAYS;
> > +			xfs_mount_set_dax_mode(mp, XFS_DAX_NEVER);
> >  		}
> >  		if (xfs_sb_version_hasreflink(&mp->m_sb)) {
> >  			xfs_alert(mp,
> > -- 
> > 2.25.1
> >
diff mbox series

Patch

diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 54bd74088936..2e88c30642e3 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -233,7 +233,8 @@  typedef struct xfs_mount {
 						   allocator */
 #define XFS_MOUNT_NOATTR2	(1ULL << 25)	/* disable use of attr2 format */
 
-#define XFS_MOUNT_DAX_ALWAYS	(1ULL << 62)	/* TEST ONLY! */
+#define XFS_MOUNT_DAX_ALWAYS	(1ULL << 62)
+#define XFS_MOUNT_DAX_NEVER	(1ULL << 63)
 
 /*
  * Max and min values for mount-option defined I/O
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 3863f41757d2..142e5d03566f 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -47,6 +47,32 @@  static struct kset *xfs_kset;		/* top-level xfs sysfs dir */
 static struct xfs_kobj xfs_dbg_kobj;	/* global debug sysfs attrs */
 #endif
 
+enum {
+	XFS_DAX_INODE = 0,
+	XFS_DAX_ALWAYS = 1,
+	XFS_DAX_NEVER = 2,
+};
+
+static void xfs_mount_set_dax_mode(struct xfs_mount *mp, u32 val)
+{
+	if (val == XFS_DAX_INODE) {
+		mp->m_flags &= ~(XFS_MOUNT_DAX_ALWAYS | XFS_MOUNT_DAX_NEVER);
+	} else if (val == XFS_DAX_ALWAYS) {
+		mp->m_flags |= XFS_MOUNT_DAX_ALWAYS;
+		mp->m_flags &= ~XFS_MOUNT_DAX_NEVER;
+	} else if (val == XFS_DAX_NEVER) {
+		mp->m_flags |= XFS_MOUNT_DAX_NEVER;
+		mp->m_flags &= ~XFS_MOUNT_DAX_ALWAYS;
+	}
+}
+
+static const struct constant_table dax_param_enums[] = {
+	{"inode",	XFS_DAX_INODE },
+	{"always",	XFS_DAX_ALWAYS },
+	{"never",	XFS_DAX_NEVER },
+	{}
+};
+
 /*
  * Table driven mount option parser.
  */
@@ -59,7 +85,7 @@  enum {
 	Opt_filestreams, Opt_quota, Opt_noquota, Opt_usrquota, Opt_grpquota,
 	Opt_prjquota, Opt_uquota, Opt_gquota, Opt_pquota,
 	Opt_uqnoenforce, Opt_gqnoenforce, Opt_pqnoenforce, Opt_qnoenforce,
-	Opt_discard, Opt_nodiscard, Opt_dax,
+	Opt_discard, Opt_nodiscard, Opt_dax, Opt_dax_enum,
 };
 
 static const struct fs_parameter_spec xfs_fs_parameters[] = {
@@ -103,6 +129,7 @@  static const struct fs_parameter_spec xfs_fs_parameters[] = {
 	fsparam_flag("discard",		Opt_discard),
 	fsparam_flag("nodiscard",	Opt_nodiscard),
 	fsparam_flag("dax",		Opt_dax),
+	fsparam_enum("dax",		Opt_dax_enum, dax_param_enums),
 	{}
 };
 
@@ -129,7 +156,6 @@  xfs_fs_show_options(
 		{ XFS_MOUNT_GRPID,		",grpid" },
 		{ XFS_MOUNT_DISCARD,		",discard" },
 		{ XFS_MOUNT_LARGEIO,		",largeio" },
-		{ XFS_MOUNT_DAX_ALWAYS,		",dax" },
 		{ 0, NULL }
 	};
 	struct xfs_mount	*mp = XFS_M(root->d_sb);
@@ -185,6 +211,13 @@  xfs_fs_show_options(
 	if (!(mp->m_qflags & XFS_ALL_QUOTA_ACCT))
 		seq_puts(m, ",noquota");
 
+	if (mp->m_flags & XFS_MOUNT_DAX_ALWAYS)
+		seq_puts(m, ",dax=always");
+	else if (mp->m_flags & XFS_MOUNT_DAX_NEVER)
+		seq_puts(m, ",dax=never");
+	else
+		seq_puts(m, ",dax=inode");
+
 	return 0;
 }
 
@@ -1244,7 +1277,10 @@  xfs_fc_parse_param(
 		return 0;
 #ifdef CONFIG_FS_DAX
 	case Opt_dax:
-		mp->m_flags |= XFS_MOUNT_DAX_ALWAYS;
+		xfs_mount_set_dax_mode(mp, XFS_DAX_ALWAYS);
+		return 0;
+	case Opt_dax_enum:
+		xfs_mount_set_dax_mode(mp, result.uint_32);
 		return 0;
 #endif
 	default:
@@ -1451,7 +1487,7 @@  xfs_fc_fill_super(
 		if (!rtdev_is_dax && !datadev_is_dax) {
 			xfs_alert(mp,
 			"DAX unsupported by block device. Turning off DAX.");
-			mp->m_flags &= ~XFS_MOUNT_DAX_ALWAYS;
+			xfs_mount_set_dax_mode(mp, XFS_DAX_NEVER);
 		}
 		if (xfs_sb_version_hasreflink(&mp->m_sb)) {
 			xfs_alert(mp,