[PATCH V9 07/11] fs/xfs: Combine xfs_diflags_to_linux() and xfs_diflags_to_iflags()

From: ira . weiny
Date: Tue Apr 21 2020 - 15:18:27 EST


From: Ira Weiny <ira.weiny@xxxxxxxxx>

The functionality in xfs_diflags_to_linux() and xfs_diflags_to_iflags() are
nearly identical. The only difference is that *_to_linux() is called after
inode setup and disallows changing the DAX flag.

Combining them can be done with a flag which indicates if this is the initial
setup to allow the DAX flag to be properly set only at init time.

So remove xfs_diflags_to_linux() and call the modified xfs_diflags_to_iflags()
directly.

While we are here simplify xfs_diflags_to_iflags() to take struct xfs_inode and
use xfs_ip2xflags() to ensure future diflags are included correctly.

Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>

---
Changes from V7:
Clarify with a comment the reason for leaving S_DAX out of the
mask

Changes from V6:
Move unrelated hunk to previous patch.
Change logic for better code generation.

Changes from V5:
The functions are no longer identical so we can only combine
them rather than deleting one completely. This is reflected in
the new init parameter.
---
fs/xfs/xfs_inode.h | 1 +
fs/xfs/xfs_ioctl.c | 33 +--------------------------------
fs/xfs/xfs_iops.c | 46 +++++++++++++++++++++++++++-------------------
3 files changed, 29 insertions(+), 51 deletions(-)

diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index c6a63f6764a6..83073c883fbf 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -467,6 +467,7 @@ int xfs_break_layouts(struct inode *inode, uint *iolock,
/* from xfs_iops.c */
extern void xfs_setup_inode(struct xfs_inode *ip);
extern void xfs_setup_iops(struct xfs_inode *ip);
+extern void xfs_diflags_to_iflags(struct xfs_inode *ip, bool init);

/*
* When setting up a newly allocated inode, we need to call
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 309958186d33..104495ac187c 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1201,37 +1201,6 @@ xfs_flags2diflags2(
return di_flags2;
}

-STATIC void
-xfs_diflags_to_linux(
- struct xfs_inode *ip)
-{
- struct inode *inode = VFS_I(ip);
- unsigned int xflags = xfs_ip2xflags(ip);
-
- if (xflags & FS_XFLAG_IMMUTABLE)
- inode->i_flags |= S_IMMUTABLE;
- else
- inode->i_flags &= ~S_IMMUTABLE;
- if (xflags & FS_XFLAG_APPEND)
- inode->i_flags |= S_APPEND;
- else
- inode->i_flags &= ~S_APPEND;
- if (xflags & FS_XFLAG_SYNC)
- inode->i_flags |= S_SYNC;
- else
- inode->i_flags &= ~S_SYNC;
- if (xflags & FS_XFLAG_NOATIME)
- inode->i_flags |= S_NOATIME;
- else
- inode->i_flags &= ~S_NOATIME;
-#if 0 /* disabled until the flag switching races are sorted out */
- if (xflags & FS_XFLAG_DAX)
- inode->i_flags |= S_DAX;
- else
- inode->i_flags &= ~S_DAX;
-#endif
-}
-
static int
xfs_ioctl_setattr_xflags(
struct xfs_trans *tp,
@@ -1269,7 +1238,7 @@ xfs_ioctl_setattr_xflags(
ip->i_d.di_flags = xfs_flags2diflags(ip, fa->fsx_xflags);
ip->i_d.di_flags2 = di_flags2;

- xfs_diflags_to_linux(ip);
+ xfs_diflags_to_iflags(ip, false);
xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
XFS_STATS_INC(mp, xs_ig_attrchg);
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 1814f10e43d3..b70b735fe4a4 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -1276,26 +1276,34 @@ xfs_inode_should_enable_dax(
return false;
}

-STATIC void
+void
xfs_diflags_to_iflags(
- struct inode *inode,
- struct xfs_inode *ip)
+ struct xfs_inode *ip,
+ bool init)
{
- uint16_t flags = ip->i_d.di_flags;
-
- inode->i_flags &= ~(S_IMMUTABLE | S_APPEND | S_SYNC |
- S_NOATIME | S_DAX);
-
- if (flags & XFS_DIFLAG_IMMUTABLE)
- inode->i_flags |= S_IMMUTABLE;
- if (flags & XFS_DIFLAG_APPEND)
- inode->i_flags |= S_APPEND;
- if (flags & XFS_DIFLAG_SYNC)
- inode->i_flags |= S_SYNC;
- if (flags & XFS_DIFLAG_NOATIME)
- inode->i_flags |= S_NOATIME;
- if (xfs_inode_should_enable_dax(ip))
- inode->i_flags |= S_DAX;
+ struct inode *inode = VFS_I(ip);
+ unsigned int xflags = xfs_ip2xflags(ip);
+ unsigned int flags = 0;
+
+ ASSERT(!(IS_DAX(inode) && init));
+
+ if (xflags & FS_XFLAG_IMMUTABLE)
+ flags |= S_IMMUTABLE;
+ if (xflags & FS_XFLAG_APPEND)
+ flags |= S_APPEND;
+ if (xflags & FS_XFLAG_SYNC)
+ flags |= S_SYNC;
+ if (xflags & FS_XFLAG_NOATIME)
+ flags |= S_NOATIME;
+ if (init && xfs_inode_should_enable_dax(ip))
+ flags |= S_DAX;
+
+ /*
+ * S_DAX can only be set during inode initialization and is never set by
+ * the VFS, so we cannot mask off S_DAX in i_flags.
+ */
+ inode->i_flags &= ~(S_IMMUTABLE | S_APPEND | S_SYNC | S_NOATIME);
+ inode->i_flags |= flags;
}

/*
@@ -1321,7 +1329,7 @@ xfs_setup_inode(
inode_fake_hash(inode);

i_size_write(inode, ip->i_d.di_size);
- xfs_diflags_to_iflags(inode, ip);
+ xfs_diflags_to_iflags(ip, true);

if (S_ISDIR(inode->i_mode)) {
/*
--
2.25.1