[email protected] (Maxime Villard) writes:
>Hi,
>this may be a stupid question; in ufs/ffs/ffs_vfsops.c, l.1153:
> if (fs->fs_sbsize < SBLOCKSIZE)
> brelse(bp, BC_INVAL);
> else
> brelse(bp, 0);
>However 'fs->fs_sbsize' is *always* smaller than SBLOCKSIZE. So only
>the first branch is reached.
It can also be equal to SBLOCKSIZE (or larger than SBLOCKSIZE if corrupted).
>I don't understand what the BC_INVAL flag means, and its definition
>in sys/buf.h is not very enlightening:
> #define BC_INVAL 0x00002000 /* Does not contain valid info.
> */
BC_INVAL means, there is no data in the buffer that could be reused.
The buffer will be put at the head of the freelist.
I don't think that the check makes any sense, but an equivalent already
existed since the beginning:
if (fs->fs_sbsize < SBSIZE)
bp->b_flags |= B_INVAL;
brelse(bp);
--
--
Michael van Elst
Internet: [email protected]
"A potential Snark may lurk in every tree."
