Date: Thu, 15 Nov 2018 21:58:22 +0000 From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 233245] [UFS] Softupdates fails to track dependency between appended data and i_size Message-ID: <bug-233245-227@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=233245 Bug ID: 233245 Summary: [UFS] Softupdates fails to track dependency between appended data and i_size Product: Base System Version: CURRENT Hardware: Any OS: Any Status: New Severity: Affects Only Me Priority: --- Component: kern Assignee: bugs@FreeBSD.org Reporter: cem@freebsd.org This manifests with recently appended files containing extraneous zero data at the end of the file after power loss or crash. Detection of append could happen in either ffs_balloc_ufs[12] (which is where most softdep dependencies seem to be added, and which is called unconditionally by ffs_write()) in the several "happy" cases where we discover we do not need to actually allocate a new block, e.g., cases like: 753 if (lbn < UFS_NDADDR) { ... 756 nb = dp->di_db[lbn]; 757 if (nb != 0 && ip->i_size >= smalllblktosize(fs, lbn + 1)) { 758 error = bread_gb(vp, lbn, fs->fs_bsize, NOCRED, 759 gbflags, &bp); ... 764 bp->b_blkno = fsbtodb(fs, nb); +++ if (DOINGSOFTDEP(vp) && startoffset + size > ip->i_size) +++ softdep_setup_append(...); 765 *bpp = bp; 766 return (0); It could also just be checked in a single location in ffs_write() itself: 754 for (error = 0; uio->uio_resid > 0;) { 755 lbn = lblkno(fs, uio->uio_offset); 756 blkoffset = blkoff(fs, uio->uio_offset); ... 781 if (uio->uio_offset + xfersize > ip->i_size) { +++ if (DOINGSOFTDEP(vp)) +++ softdep_setup_append(...); 782 ip->i_size = uio->uio_offset + xfersize; 783 DIP_SET(ip, i_size, ip->i_size); 784 } Append data could probably be tracked in quite similar fashion to diradd (directory entry adds). -- You are receiving this mail because: You are the assignee for the bug.
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