allocated to extend the file to the new size. Releasing all pages
may release pages that contains previously-written data not yet flushed
to disk. Should fix PR kern/35704
- {ffs,lfs,ext2fs}_truncate(): Even if the inode's size is the same as
the new length, call uvm_vnp_setsize(). *_truncate() may have been
called by *_write() in the error path (e.g. block allocation failure
because of quota of file system full), and at this point v_writesize
has been set to the desired size of the file and not reverted to the
old size. Not adjusting v_writesize to the real size cause
genfs_do_io() to write to disk past the real end of the file.