diff mbox

[3/3] xfs: persist S_IOMAP_IMMUTABLE in di_flags2

Message ID 150135742595.35318.6882401569584241548.stgit@dwillia2-desk3.amr.corp.intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Dan Williams July 29, 2017, 7:43 p.m. UTC
Record the immutable state in the on-disk inode so that on the next boot
the protections against reflink and hole punch etc are automatically
restored.

This deliberately does not add a FS_XFLAG_IOMAP_IMMUTABLE since
fallocate(2) is the path to toggle this flag.

Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Suggested-by: Dave Chinner <david@fromorbit.com>
Suggested-by: "Darrick J. Wong" <darrick.wong@oracle.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 fs/xfs/libxfs/xfs_format.h |    5 ++++-
 fs/xfs/xfs_bmap_util.c     |   14 +++++++++++---
 fs/xfs/xfs_bmap_util.h     |    2 +-
 fs/xfs/xfs_file.c          |    4 ++--
 fs/xfs/xfs_ioctl.c         |    4 ++--
 fs/xfs/xfs_iops.c          |    8 +++++---
 6 files changed, 25 insertions(+), 12 deletions(-)

Comments

Darrick J. Wong July 31, 2017, 5:15 p.m. UTC | #1
On Sat, Jul 29, 2017 at 12:43:46PM -0700, Dan Williams wrote:
> Record the immutable state in the on-disk inode so that on the next boot
> the protections against reflink and hole punch etc are automatically
> restored.
> 
> This deliberately does not add a FS_XFLAG_IOMAP_IMMUTABLE since
> fallocate(2) is the path to toggle this flag.
> 
> Cc: Jan Kara <jack@suse.cz>
> Cc: Jeff Moyer <jmoyer@redhat.com>
> Cc: Christoph Hellwig <hch@lst.de>
> Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
> Cc: Alexander Viro <viro@zeniv.linux.org.uk>
> Suggested-by: Dave Chinner <david@fromorbit.com>
> Suggested-by: "Darrick J. Wong" <darrick.wong@oracle.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> ---
>  fs/xfs/libxfs/xfs_format.h |    5 ++++-
>  fs/xfs/xfs_bmap_util.c     |   14 +++++++++++---
>  fs/xfs/xfs_bmap_util.h     |    2 +-
>  fs/xfs/xfs_file.c          |    4 ++--
>  fs/xfs/xfs_ioctl.c         |    4 ++--
>  fs/xfs/xfs_iops.c          |    8 +++++---
>  6 files changed, 25 insertions(+), 12 deletions(-)
> 
> diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
> index d4d9bef20c3a..9e720e55776b 100644
> --- a/fs/xfs/libxfs/xfs_format.h
> +++ b/fs/xfs/libxfs/xfs_format.h
> @@ -1063,12 +1063,15 @@ static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
>  #define XFS_DIFLAG2_DAX_BIT	0	/* use DAX for this inode */
>  #define XFS_DIFLAG2_REFLINK_BIT	1	/* file's blocks may be shared */
>  #define XFS_DIFLAG2_COWEXTSIZE_BIT   2  /* copy on write extent size hint */
> +#define XFS_DIFLAG2_IOMAP_IMMUTABLE_BIT 3 /* set S_IOMAP_IMMUTABLE for this inode */
>  #define XFS_DIFLAG2_DAX		(1 << XFS_DIFLAG2_DAX_BIT)
>  #define XFS_DIFLAG2_REFLINK     (1 << XFS_DIFLAG2_REFLINK_BIT)
>  #define XFS_DIFLAG2_COWEXTSIZE  (1 << XFS_DIFLAG2_COWEXTSIZE_BIT)
> +#define XFS_DIFLAG2_IOMAP_IMMUTABLE (1 << XFS_DIFLAG2_IOMAP_IMMUTABLE_BIT)
>  
>  #define XFS_DIFLAG2_ANY \
> -	(XFS_DIFLAG2_DAX | XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE)
> +	(XFS_DIFLAG2_DAX | XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE | \
> +	 XFS_DIFLAG2_IOMAP_IMMUTABLE)
>  
>  /*
>   * Inode number format:
> diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
> index c4fc79a0704f..1dcb521da456 100644
> --- a/fs/xfs/xfs_bmap_util.c
> +++ b/fs/xfs/xfs_bmap_util.c
> @@ -1021,7 +1021,8 @@ xfs_alloc_file_space(
>  	struct xfs_inode	*ip,
>  	xfs_off_t		offset,
>  	xfs_off_t		len,
> -	int			alloc_type)
> +	int			alloc_type,
> +	uint64_t		di_flags2)
>  {
>  	xfs_mount_t		*mp = ip->i_mount;
>  	xfs_off_t		count;
> @@ -1119,6 +1120,12 @@ xfs_alloc_file_space(
>  			break;
>  		}
>  		xfs_ilock(ip, XFS_ILOCK_EXCL);
> +		if (di_flags2) {
> +			/* fold inode attributes for this allocation */
> +			ip->i_d.di_flags2 |= di_flags2;
> +			di_flags2 = 0;

Can we set the inode flag in xfs_seal_file_space instead of plumbing
di_flags2 all over the place into the bmap routines?

Also, what does

  xfs_alloc_file_space(..., XFS_BMAPI_ATTRFORK, XFS_DIFLAG2_REFLINK);

mean? :)

--D

> +		}
> +
>  		error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks,
>  						      0, quota_flag);
>  		if (error)
> @@ -1381,7 +1388,7 @@ xfs_zero_file_space(
>  	error = xfs_alloc_file_space(ip, round_down(offset, blksize),
>  				     round_up(offset + len, blksize) -
>  				     round_down(offset, blksize),
> -				     XFS_BMAPI_PREALLOC);
> +				     XFS_BMAPI_PREALLOC, 0);
>  out:
>  	return error;
>  
> @@ -1461,7 +1468,8 @@ xfs_seal_file_space(
>  		goto err;
>  
>  	error = xfs_alloc_file_space(ip, offset, len,
> -			XFS_BMAPI_CONVERT | XFS_BMAPI_ZERO);
> +			XFS_BMAPI_CONVERT | XFS_BMAPI_ZERO,
> +			XFS_DIFLAG2_IOMAP_IMMUTABLE);
>  	if (error)
>  		goto err;
>  
> diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h
> index 5115a32a2483..1698e0c58b78 100644
> --- a/fs/xfs/xfs_bmap_util.h
> +++ b/fs/xfs/xfs_bmap_util.h
> @@ -51,7 +51,7 @@ int	xfs_bmap_last_extent(struct xfs_trans *tp, struct xfs_inode *ip,
>  
>  /* preallocation and hole punch interface */
>  int	xfs_alloc_file_space(struct xfs_inode *ip, xfs_off_t offset,
> -			     xfs_off_t len, int alloc_type);
> +			     xfs_off_t len, int alloc_type, uint64_t di_flags2);
>  int	xfs_free_file_space(struct xfs_inode *ip, xfs_off_t offset,
>  			    xfs_off_t len);
>  int	xfs_zero_file_space(struct xfs_inode *ip, xfs_off_t offset,
> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> index e21121530a90..2d9ffa1773bd 100644
> --- a/fs/xfs/xfs_file.c
> +++ b/fs/xfs/xfs_file.c
> @@ -837,12 +837,12 @@ xfs_file_fallocate(
>  					goto out_unlock;
>  
>  				error = xfs_alloc_file_space(ip, offset, len,
> -						XFS_BMAPI_PREALLOC);
> +						XFS_BMAPI_PREALLOC, 0);
>  			} else if (mode & FALLOC_FL_SEAL_BLOCK_MAP) {
>  				error = xfs_seal_file_space(ip, offset, len);
>  			} else
>  				error = xfs_alloc_file_space(ip, offset, len,
> -						XFS_BMAPI_PREALLOC);
> +						XFS_BMAPI_PREALLOC, 0);
>  		}
>  		if (error)
>  			goto out_unlock;
> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
> index 2e64488bc4de..c829f85bed99 100644
> --- a/fs/xfs/xfs_ioctl.c
> +++ b/fs/xfs/xfs_ioctl.c
> @@ -703,7 +703,7 @@ xfs_ioc_space(
>  	case XFS_IOC_RESVSP64:
>  		flags |= XFS_PREALLOC_SET;
>  		error = xfs_alloc_file_space(ip, bf->l_start, bf->l_len,
> -						XFS_BMAPI_PREALLOC);
> +						XFS_BMAPI_PREALLOC, 0);
>  		break;
>  	case XFS_IOC_UNRESVSP:
>  	case XFS_IOC_UNRESVSP64:
> @@ -716,7 +716,7 @@ xfs_ioc_space(
>  		flags |= XFS_PREALLOC_CLEAR;
>  		if (bf->l_start > XFS_ISIZE(ip)) {
>  			error = xfs_alloc_file_space(ip, XFS_ISIZE(ip),
> -					bf->l_start - XFS_ISIZE(ip), 0);
> +					bf->l_start - XFS_ISIZE(ip), 0, 0);
>  			if (error)
>  				goto out_unlock;
>  		}
> diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> index 469c9fa4c178..174ef95453f5 100644
> --- a/fs/xfs/xfs_iops.c
> +++ b/fs/xfs/xfs_iops.c
> @@ -1186,9 +1186,10 @@ xfs_diflags_to_iflags(
>  	struct xfs_inode	*ip)
>  {
>  	uint16_t		flags = ip->i_d.di_flags;
> +	uint64_t		flags2 = ip->i_d.di_flags2;
>  
>  	inode->i_flags &= ~(S_IMMUTABLE | S_APPEND | S_SYNC |
> -			    S_NOATIME | S_DAX);
> +			    S_NOATIME | S_DAX | S_IOMAP_IMMUTABLE);
>  
>  	if (flags & XFS_DIFLAG_IMMUTABLE)
>  		inode->i_flags |= S_IMMUTABLE;
> @@ -1201,9 +1202,10 @@ xfs_diflags_to_iflags(
>  	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))
> +	    (ip->i_mount->m_flags & XFS_MOUNT_DAX || flags2 & XFS_DIFLAG2_DAX))
>  		inode->i_flags |= S_DAX;
> +	if (flags2 & XFS_DIFLAG2_IOMAP_IMMUTABLE)
> +		inode->i_flags |= S_IOMAP_IMMUTABLE;
>  }
>  
>  /*
> 
> --
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Dave Chinner Aug. 1, 2017, 12:42 a.m. UTC | #2
On Sat, Jul 29, 2017 at 12:43:46PM -0700, Dan Williams wrote:
> Record the immutable state in the on-disk inode so that on the next boot
> the protections against reflink and hole punch etc are automatically
> restored.

Keep in mind we can't do this without all the userspace side support
for the addition to the in-disk format....

> This deliberately does not add a FS_XFLAG_IOMAP_IMMUTABLE since
> fallocate(2) is the path to toggle this flag.

That's a problem. The flag needs to be added so that we can /view/
the state of the inode through xfs_io. Just because we can't set it
through the extended inode flag interface doesn't mean the flag
should not exist.

> diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
> index c4fc79a0704f..1dcb521da456 100644
> --- a/fs/xfs/xfs_bmap_util.c
> +++ b/fs/xfs/xfs_bmap_util.c
> @@ -1021,7 +1021,8 @@ xfs_alloc_file_space(
>  	struct xfs_inode	*ip,
>  	xfs_off_t		offset,
>  	xfs_off_t		len,
> -	int			alloc_type)
> +	int			alloc_type,
> +	uint64_t		di_flags2)
>  {
>  	xfs_mount_t		*mp = ip->i_mount;
>  	xfs_off_t		count;
> @@ -1119,6 +1120,12 @@ xfs_alloc_file_space(
>  			break;
>  		}
>  		xfs_ilock(ip, XFS_ILOCK_EXCL);
> +		if (di_flags2) {
> +			/* fold inode attributes for this allocation */
> +			ip->i_d.di_flags2 |= di_flags2;
> +			di_flags2 = 0;
> +		}

Yikes, no! Darrick already mentioned this, but it needs pointing out
again...

Especially as it means that we are setting the immutable flag before
we've allocated all the extents to fill the file space. If we've
implemented immutable extent maps correctly, then xfs_bmapi_write()
should be rejecting any attempt to allocate or modify extents if
that flag is set on the inode, which means this code will now fail
to allocate/zero anything...

IOWs, this flag should be the last thing that is set on the inode
once it's been fully allocated and zeroed.

Cheers,

Dave.
diff mbox

Patch

diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index d4d9bef20c3a..9e720e55776b 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -1063,12 +1063,15 @@  static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
 #define XFS_DIFLAG2_DAX_BIT	0	/* use DAX for this inode */
 #define XFS_DIFLAG2_REFLINK_BIT	1	/* file's blocks may be shared */
 #define XFS_DIFLAG2_COWEXTSIZE_BIT   2  /* copy on write extent size hint */
+#define XFS_DIFLAG2_IOMAP_IMMUTABLE_BIT 3 /* set S_IOMAP_IMMUTABLE for this inode */
 #define XFS_DIFLAG2_DAX		(1 << XFS_DIFLAG2_DAX_BIT)
 #define XFS_DIFLAG2_REFLINK     (1 << XFS_DIFLAG2_REFLINK_BIT)
 #define XFS_DIFLAG2_COWEXTSIZE  (1 << XFS_DIFLAG2_COWEXTSIZE_BIT)
+#define XFS_DIFLAG2_IOMAP_IMMUTABLE (1 << XFS_DIFLAG2_IOMAP_IMMUTABLE_BIT)
 
 #define XFS_DIFLAG2_ANY \
-	(XFS_DIFLAG2_DAX | XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE)
+	(XFS_DIFLAG2_DAX | XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE | \
+	 XFS_DIFLAG2_IOMAP_IMMUTABLE)
 
 /*
  * Inode number format:
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index c4fc79a0704f..1dcb521da456 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1021,7 +1021,8 @@  xfs_alloc_file_space(
 	struct xfs_inode	*ip,
 	xfs_off_t		offset,
 	xfs_off_t		len,
-	int			alloc_type)
+	int			alloc_type,
+	uint64_t		di_flags2)
 {
 	xfs_mount_t		*mp = ip->i_mount;
 	xfs_off_t		count;
@@ -1119,6 +1120,12 @@  xfs_alloc_file_space(
 			break;
 		}
 		xfs_ilock(ip, XFS_ILOCK_EXCL);
+		if (di_flags2) {
+			/* fold inode attributes for this allocation */
+			ip->i_d.di_flags2 |= di_flags2;
+			di_flags2 = 0;
+		}
+
 		error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks,
 						      0, quota_flag);
 		if (error)
@@ -1381,7 +1388,7 @@  xfs_zero_file_space(
 	error = xfs_alloc_file_space(ip, round_down(offset, blksize),
 				     round_up(offset + len, blksize) -
 				     round_down(offset, blksize),
-				     XFS_BMAPI_PREALLOC);
+				     XFS_BMAPI_PREALLOC, 0);
 out:
 	return error;
 
@@ -1461,7 +1468,8 @@  xfs_seal_file_space(
 		goto err;
 
 	error = xfs_alloc_file_space(ip, offset, len,
-			XFS_BMAPI_CONVERT | XFS_BMAPI_ZERO);
+			XFS_BMAPI_CONVERT | XFS_BMAPI_ZERO,
+			XFS_DIFLAG2_IOMAP_IMMUTABLE);
 	if (error)
 		goto err;
 
diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h
index 5115a32a2483..1698e0c58b78 100644
--- a/fs/xfs/xfs_bmap_util.h
+++ b/fs/xfs/xfs_bmap_util.h
@@ -51,7 +51,7 @@  int	xfs_bmap_last_extent(struct xfs_trans *tp, struct xfs_inode *ip,
 
 /* preallocation and hole punch interface */
 int	xfs_alloc_file_space(struct xfs_inode *ip, xfs_off_t offset,
-			     xfs_off_t len, int alloc_type);
+			     xfs_off_t len, int alloc_type, uint64_t di_flags2);
 int	xfs_free_file_space(struct xfs_inode *ip, xfs_off_t offset,
 			    xfs_off_t len);
 int	xfs_zero_file_space(struct xfs_inode *ip, xfs_off_t offset,
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index e21121530a90..2d9ffa1773bd 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -837,12 +837,12 @@  xfs_file_fallocate(
 					goto out_unlock;
 
 				error = xfs_alloc_file_space(ip, offset, len,
-						XFS_BMAPI_PREALLOC);
+						XFS_BMAPI_PREALLOC, 0);
 			} else if (mode & FALLOC_FL_SEAL_BLOCK_MAP) {
 				error = xfs_seal_file_space(ip, offset, len);
 			} else
 				error = xfs_alloc_file_space(ip, offset, len,
-						XFS_BMAPI_PREALLOC);
+						XFS_BMAPI_PREALLOC, 0);
 		}
 		if (error)
 			goto out_unlock;
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 2e64488bc4de..c829f85bed99 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -703,7 +703,7 @@  xfs_ioc_space(
 	case XFS_IOC_RESVSP64:
 		flags |= XFS_PREALLOC_SET;
 		error = xfs_alloc_file_space(ip, bf->l_start, bf->l_len,
-						XFS_BMAPI_PREALLOC);
+						XFS_BMAPI_PREALLOC, 0);
 		break;
 	case XFS_IOC_UNRESVSP:
 	case XFS_IOC_UNRESVSP64:
@@ -716,7 +716,7 @@  xfs_ioc_space(
 		flags |= XFS_PREALLOC_CLEAR;
 		if (bf->l_start > XFS_ISIZE(ip)) {
 			error = xfs_alloc_file_space(ip, XFS_ISIZE(ip),
-					bf->l_start - XFS_ISIZE(ip), 0);
+					bf->l_start - XFS_ISIZE(ip), 0, 0);
 			if (error)
 				goto out_unlock;
 		}
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 469c9fa4c178..174ef95453f5 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -1186,9 +1186,10 @@  xfs_diflags_to_iflags(
 	struct xfs_inode	*ip)
 {
 	uint16_t		flags = ip->i_d.di_flags;
+	uint64_t		flags2 = ip->i_d.di_flags2;
 
 	inode->i_flags &= ~(S_IMMUTABLE | S_APPEND | S_SYNC |
-			    S_NOATIME | S_DAX);
+			    S_NOATIME | S_DAX | S_IOMAP_IMMUTABLE);
 
 	if (flags & XFS_DIFLAG_IMMUTABLE)
 		inode->i_flags |= S_IMMUTABLE;
@@ -1201,9 +1202,10 @@  xfs_diflags_to_iflags(
 	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))
+	    (ip->i_mount->m_flags & XFS_MOUNT_DAX || flags2 & XFS_DIFLAG2_DAX))
 		inode->i_flags |= S_DAX;
+	if (flags2 & XFS_DIFLAG2_IOMAP_IMMUTABLE)
+		inode->i_flags |= S_IOMAP_IMMUTABLE;
 }
 
 /*