Maxim Sobolev e8534ba3ad ufs: do not let a rolled back inode write end a data-only sync ...

With soft updates, ffs_syncvnode() writes the inode between its passes
while buffers are still dirty.  That write can go out with new block
pointers rolled back, for instance a new indirect block whose contents
are only written in a later pass, yet ffs_update() clears IN_SIZEMOD
and IN_IBLKDATA because the write was synchronous.  A data-only sync
then decides at the end that the inode need not be written, and
fdatasync(2) or an O_DSYNC write that allocated the first indirect
block returned with the on-disk inode not pointing to it.

Note on entry whether a data-only sync has to write the inode, and base
the final write, done once all dependencies are flushed, on that alone:
nothing else can set IN_SIZEMOD or IN_IBLKDATA meanwhile, as the vnode
is locked.  A full sync always writes the inode last and was not
affected.

Sponsored by:   Sippy Software, Inc.
Reviewed by:    kib
Tested by:      pho
Differential Revision:  https://reviews.freebsd.org/D60134
MFC after:      1 month

2026-10-12 21:28:32 -07:00

..

ffs

ufs: do not let a rolled back inode write end a data-only sync

2026-10-12 21:28:32 -07:00

ufs

ufs: do not busy or reference the mount in ufs_sync_nlink()

2026-10-12 21:00:26 -07:00