Third part of new DAX code for 5.8:

- Teach XFS to ask the VFS to drop an inode if the administrator changes
   the FS_XFLAG_DAX inode flag such that the S_DAX state would change.
   This can result in files changing access modes without requiring an
   unmount cycle.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEUzaAxoMeQq6m2jMV+H93GTRKtOsFAl7WezgACgkQ+H93GTRK
 tOvGCg//QCKK9yEBE0sjR0hjeJwmvoxAtdCGyrq+h1wZ1OI+iZCy3K4D9+/NSl/Z
 SajLB2bK2mJBBZmERJlRITnTwSFbHX5roMHK4NDTqRAusHdm92JxMWds5ZMXGuTD
 HiJ3Luu4VWHBuraRB5JKxHWyDc57xSE0kC1KwPySQCNAuDv+YS42uZMAM6284T/J
 hkE4odUztykN+tOZj/nY+FiRjhzLF93cghMmRlDlgmibyHGLMhrfEmaMj99eCA5O
 PVepVA6Vk0IHWviAWS8vqX2LADQaP1U2RP4racBAdmk+Z6kqUV+KSotJU1O+6ey/
 Zfnr4VytKxmxngXhR4wnQcu3sIZqDdZRF4mcngE/G1yJXKim5iwVX+D04BsvDOpo
 OpND9+dOuh4ecbayfOGxp9lmBsPQBzI/qPpUcpbtsRd5xN5IyTL6MyNsSPJg2ZrG
 5BaSUO+Hw6hmBcB5MLF36XBuj25QEITl/hxy66Ym2BiQT5im9a3JxRlj8OvoWEVI
 1323WehvPSA1bl7m1mNQyE7/h7TjeGA6LiTplSxPqencKzXn93wcTDV09GOZ11No
 UEb+yC97hzRepEq4hSTr7tu18RN04ryA28/Vtcm/YeeM2bQ5WpI6jTd3b7g55BE2
 EuUGAUFLZRKsvSnLhg/GbuaW442osAKuNttIL1NEyPs0Iw76Ero=
 =mKZf
 -----END PGP SIGNATURE-----

Merge tag 'vfs-5.8-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull DAX updates part three from Darrick Wong:
 "Now that the xfs changes have landed, this third piece changes the
  FS_XFLAG_DAX ioctl code in xfs to request that the inode be reloaded
  after the last program closes the file, if doing so would make a S_DAX
  change happen. The goal here is to make dax access mode switching
  quicker when possible.

  Summary:

   - Teach XFS to ask the VFS to drop an inode if the administrator
     changes the FS_XFLAG_DAX inode flag such that the S_DAX state would
     change. This can result in files changing access modes without
     requiring an unmount cycle"

* tag 'vfs-5.8-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  fs/xfs: Update xfs_ioctl_setattr_dax_invalidate()
  fs/xfs: Combine xfs_diflags_to_linux() and xfs_diflags_to_iflags()
  fs/xfs: Create function xfs_inode_should_enable_dax()
  fs/xfs: Make DAX mount option a tri-state
  fs/xfs: Change XFS_MOUNT_DAX to XFS_MOUNT_DAX_ALWAYS
  fs/xfs: Remove unnecessary initialization of i_rwsem
This commit is contained in:
Linus Torvalds 2020-06-11 10:48:12 -07:00
commit 7cf035cc83

View File

@ -1236,64 +1236,26 @@ xfs_ioctl_setattr_xflags(
return 0;
}
/*
* If we are changing DAX flags, we have to ensure the file is clean and any
* cached objects in the address space are invalidated and removed. This
* requires us to lock out other IO and page faults similar to a truncate
* operation. The locks need to be held until the transaction has been committed
* so that the cache invalidation is atomic with respect to the DAX flag
* manipulation.
*/
static int
xfs_ioctl_setattr_dax_invalidate(
static void
xfs_ioctl_setattr_prepare_dax(
struct xfs_inode *ip,
struct fsxattr *fa,
int *join_flags)
struct fsxattr *fa)
{
struct inode *inode = VFS_I(ip);
struct super_block *sb = inode->i_sb;
int error;
*join_flags = 0;
/*
* It is only valid to set the DAX flag on regular files and
* directories on filesystems where the block size is equal to the page
* size. On directories it serves as an inherited hint so we don't
* have to check the device for dax support or flush pagecache.
*/
if (fa->fsx_xflags & FS_XFLAG_DAX) {
struct xfs_buftarg *target = xfs_inode_buftarg(ip);
if (!bdev_dax_supported(target->bt_bdev, sb->s_blocksize))
return -EINVAL;
}
/* If the DAX state is not changing, we have nothing to do here. */
if ((fa->fsx_xflags & FS_XFLAG_DAX) && IS_DAX(inode))
return 0;
if (!(fa->fsx_xflags & FS_XFLAG_DAX) && !IS_DAX(inode))
return 0;
struct xfs_mount *mp = ip->i_mount;
struct inode *inode = VFS_I(ip);
if (S_ISDIR(inode->i_mode))
return 0;
return;
/* lock, flush and invalidate mapping in preparation for flag change */
xfs_ilock(ip, XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL);
error = filemap_write_and_wait(inode->i_mapping);
if (error)
goto out_unlock;
error = invalidate_inode_pages2(inode->i_mapping);
if (error)
goto out_unlock;
*join_flags = XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL;
return 0;
out_unlock:
xfs_iunlock(ip, XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL);
return error;
if ((mp->m_flags & XFS_MOUNT_DAX_ALWAYS) ||
(mp->m_flags & XFS_MOUNT_DAX_NEVER))
return;
if (((fa->fsx_xflags & FS_XFLAG_DAX) &&
!(ip->i_d.di_flags2 & XFS_DIFLAG2_DAX)) ||
(!(fa->fsx_xflags & FS_XFLAG_DAX) &&
(ip->i_d.di_flags2 & XFS_DIFLAG2_DAX)))
d_mark_dontcache(inode);
}
/*
@ -1301,17 +1263,10 @@ out_unlock:
* have permission to do so. On success, return a clean transaction and the
* inode locked exclusively ready for further operation specific checks. On
* failure, return an error without modifying or locking the inode.
*
* The inode might already be IO locked on call. If this is the case, it is
* indicated in @join_flags and we take full responsibility for ensuring they
* are unlocked from now on. Hence if we have an error here, we still have to
* unlock them. Otherwise, once they are joined to the transaction, they will
* be unlocked on commit/cancel.
*/
static struct xfs_trans *
xfs_ioctl_setattr_get_trans(
struct xfs_inode *ip,
int join_flags)
struct xfs_inode *ip)
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_trans *tp;
@ -1328,8 +1283,7 @@ xfs_ioctl_setattr_get_trans(
goto out_unlock;
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL | join_flags);
join_flags = 0;
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
/*
* CAP_FOWNER overrides the following restrictions:
@ -1350,8 +1304,6 @@ xfs_ioctl_setattr_get_trans(
out_cancel:
xfs_trans_cancel(tp);
out_unlock:
if (join_flags)
xfs_iunlock(ip, join_flags);
return ERR_PTR(error);
}
@ -1476,7 +1428,6 @@ xfs_ioctl_setattr(
struct xfs_dquot *pdqp = NULL;
struct xfs_dquot *olddquot = NULL;
int code;
int join_flags = 0;
trace_xfs_ioctl_setattr(ip);
@ -1500,18 +1451,9 @@ xfs_ioctl_setattr(
return code;
}
/*
* Changing DAX config may require inode locking for mapping
* invalidation. These need to be held all the way to transaction commit
* or cancel time, so need to be passed through to
* xfs_ioctl_setattr_get_trans() so it can apply them to the join call
* appropriately.
*/
code = xfs_ioctl_setattr_dax_invalidate(ip, fa, &join_flags);
if (code)
goto error_free_dquots;
xfs_ioctl_setattr_prepare_dax(ip, fa);
tp = xfs_ioctl_setattr_get_trans(ip, join_flags);
tp = xfs_ioctl_setattr_get_trans(ip);
if (IS_ERR(tp)) {
code = PTR_ERR(tp);
goto error_free_dquots;
@ -1639,7 +1581,6 @@ xfs_ioc_setxflags(
struct fsxattr fa;
struct fsxattr old_fa;
unsigned int flags;
int join_flags = 0;
int error;
if (copy_from_user(&flags, arg, sizeof(flags)))
@ -1656,18 +1597,9 @@ xfs_ioc_setxflags(
if (error)
return error;
/*
* Changing DAX config may require inode locking for mapping
* invalidation. These need to be held all the way to transaction commit
* or cancel time, so need to be passed through to
* xfs_ioctl_setattr_get_trans() so it can apply them to the join call
* appropriately.
*/
error = xfs_ioctl_setattr_dax_invalidate(ip, &fa, &join_flags);
if (error)
goto out_drop_write;
xfs_ioctl_setattr_prepare_dax(ip, &fa);
tp = xfs_ioctl_setattr_get_trans(ip, join_flags);
tp = xfs_ioctl_setattr_get_trans(ip);
if (IS_ERR(tp)) {
error = PTR_ERR(tp);
goto out_drop_write;