xfs: sanitise sb_bad_features2 handling
We currently have to ensure that every time we update sb_features2 that we update sb_bad_features2. Now that we log and format the superblock in it's entirety we actually don't have to care because we can simply update the sb_bad_features2 when we format it into the buffer. This removes the need for anything but the mount and superblock formatting code to care about sb_bad_features2, and hence removes the possibility that we forget to update bad_features2 when necessary in the future. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
This commit is contained in:
parent
61e63ecb57
commit
074e427ba7
|
@ -151,10 +151,13 @@ typedef struct xfs_sb {
|
|||
__uint32_t sb_features2; /* additional feature bits */
|
||||
|
||||
/*
|
||||
* bad features2 field as a result of failing to pad the sb
|
||||
* structure to 64 bits. Some machines will be using this field
|
||||
* for features2 bits. Easiest just to mark it bad and not use
|
||||
* it for anything else.
|
||||
* bad features2 field as a result of failing to pad the sb structure to
|
||||
* 64 bits. Some machines will be using this field for features2 bits.
|
||||
* Easiest just to mark it bad and not use it for anything else.
|
||||
*
|
||||
* This is not kept up to date in memory; it is always overwritten by
|
||||
* the value in sb_features2 when formatting the incore superblock to
|
||||
* the disk buffer.
|
||||
*/
|
||||
__uint32_t sb_bad_features2;
|
||||
|
||||
|
@ -453,13 +456,11 @@ static inline void xfs_sb_version_addattr2(struct xfs_sb *sbp)
|
|||
{
|
||||
sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
|
||||
sbp->sb_features2 |= XFS_SB_VERSION2_ATTR2BIT;
|
||||
sbp->sb_bad_features2 |= XFS_SB_VERSION2_ATTR2BIT;
|
||||
}
|
||||
|
||||
static inline void xfs_sb_version_removeattr2(struct xfs_sb *sbp)
|
||||
{
|
||||
sbp->sb_features2 &= ~XFS_SB_VERSION2_ATTR2BIT;
|
||||
sbp->sb_bad_features2 &= ~XFS_SB_VERSION2_ATTR2BIT;
|
||||
if (!sbp->sb_features2)
|
||||
sbp->sb_versionnum &= ~XFS_SB_VERSION_MOREBITSBIT;
|
||||
}
|
||||
|
@ -475,7 +476,6 @@ static inline void xfs_sb_version_addprojid32bit(struct xfs_sb *sbp)
|
|||
{
|
||||
sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
|
||||
sbp->sb_features2 |= XFS_SB_VERSION2_PROJID32BIT;
|
||||
sbp->sb_bad_features2 |= XFS_SB_VERSION2_PROJID32BIT;
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
|
@ -497,7 +497,6 @@ xfs_sb_to_disk(
|
|||
to->sb_fdblocks = cpu_to_be64(from->sb_fdblocks);
|
||||
to->sb_frextents = cpu_to_be64(from->sb_frextents);
|
||||
|
||||
|
||||
to->sb_flags = from->sb_flags;
|
||||
to->sb_shared_vn = from->sb_shared_vn;
|
||||
to->sb_inoalignmt = cpu_to_be32(from->sb_inoalignmt);
|
||||
|
@ -507,6 +506,13 @@ xfs_sb_to_disk(
|
|||
to->sb_logsectlog = from->sb_logsectlog;
|
||||
to->sb_logsectsize = cpu_to_be16(from->sb_logsectsize);
|
||||
to->sb_logsunit = cpu_to_be32(from->sb_logsunit);
|
||||
|
||||
/*
|
||||
* We need to ensure that bad_features2 always matches features2.
|
||||
* Hence we enforce that here rather than having to remember to do it
|
||||
* everywhere else that updates features2.
|
||||
*/
|
||||
from->sb_bad_features2 = from->sb_features2;
|
||||
to->sb_features2 = cpu_to_be32(from->sb_features2);
|
||||
to->sb_bad_features2 = cpu_to_be32(from->sb_bad_features2);
|
||||
|
||||
|
|
|
@ -640,25 +640,24 @@ xfs_mountfs(
|
|||
xfs_sb_mount_common(mp, sbp);
|
||||
|
||||
/*
|
||||
* Check for a mismatched features2 values. Older kernels
|
||||
* read & wrote into the wrong sb offset for sb_features2
|
||||
* on some platforms due to xfs_sb_t not being 64bit size aligned
|
||||
* when sb_features2 was added, which made older superblock
|
||||
* reading/writing routines swap it as a 64-bit value.
|
||||
* Check for a mismatched features2 values. Older kernels read & wrote
|
||||
* into the wrong sb offset for sb_features2 on some platforms due to
|
||||
* xfs_sb_t not being 64bit size aligned when sb_features2 was added,
|
||||
* which made older superblock reading/writing routines swap it as a
|
||||
* 64-bit value.
|
||||
*
|
||||
* For backwards compatibility, we make both slots equal.
|
||||
*
|
||||
* If we detect a mismatched field, we OR the set bits into the
|
||||
* existing features2 field in case it has already been modified; we
|
||||
* don't want to lose any features. We then update the bad location
|
||||
* with the ORed value so that older kernels will see any features2
|
||||
* flags, and mark the two fields as needing updates once the
|
||||
* transaction subsystem is online.
|
||||
* If we detect a mismatched field, we OR the set bits into the existing
|
||||
* features2 field in case it has already been modified; we don't want
|
||||
* to lose any features. We then update the bad location with the ORed
|
||||
* value so that older kernels will see any features2 flags. The
|
||||
* superblock writeback code ensures the new sb_features2 is copied to
|
||||
* sb_bad_features2 before it is logged or written to disk.
|
||||
*/
|
||||
if (xfs_sb_has_mismatched_features2(sbp)) {
|
||||
xfs_warn(mp, "correcting sb_features alignment problem");
|
||||
sbp->sb_features2 |= sbp->sb_bad_features2;
|
||||
sbp->sb_bad_features2 = sbp->sb_features2;
|
||||
mp->m_update_sb = true;
|
||||
|
||||
/*
|
||||
|
|
Loading…
Reference in a new issue