Commit Graph

11 Commits

Author SHA1 Message Date
Kirk McKusick
34816cb9ae Move the pointers stored in the superblock into a separate
fs_summary_info structure. This change was originally done
by the CheriBSD project as they need larger pointers that
do not fit in the existing superblock.

This cleanup of the superblock eases the task of the commit
that immediately follows this one.

Suggested by: brooks
Reviewed by:  kib
PR:           246983
Sponsored by: Netflix
2020-06-19 01:02:53 +00:00
Kirk McKusick
fb14e73cb4 Normally when an attempt is made to mount a UFS/FFS filesystem whose
superblock has a check-hash error, an error message noting the
superblock check-hash failure is printed and the mount fails. The
administrator then runs fsck to repair the filesystem and when
successful, the filesystem can once again be mounted.

This approach fails if the filesystem in question is a root filesystem
from which you are trying to boot. Here, the loader fails when trying
to access the filesystem to get the kernel to boot. So it is necessary
to allow the loader to ignore the superblock check-hash error and make
a best effort to read the kernel. The filesystem may be suffiently
corrupted that the read attempt fails, but there is no harm in trying
since the loader makes no attempt to write to the filesystem.

Once the kernel is loaded and starts to run, it attempts to mount its
root filesystem. Once again, failure means that it breaks to its prompt
to ask where to get its root filesystem. Unless you have an alternate
root filesystem, you are stuck.

Since the root filesystem is initially mounted read-only, it is
safe to make an attempt to mount the root filesystem with the failed
superblock check-hash. Thus, when asked to mount a root filesystem
with a failed superblock check-hash, the kernel prints a warning
message that the root filesystem superblock check-hash needs repair,
but notes that it is ignoring the error and proceeding. It does
mark the filesystem as needing an fsck which prevents it from being
enabled for writing until fsck has been run on it. The net effect
is that the reboot fails to single user, but at least at that point
the administrator has the tools at hand to fix the problem.

Reported by:    Rick Macklem (rmacklem@)
Discussed with: Warner Losh (imp@)
Sponsored by:   Netflix
2018-12-06 00:09:39 +00:00
Warner Losh
6d423eb2cb Remove unused variables.
Sponsored by: Netflix
2018-06-13 17:42:50 +00:00
Simon J. Gerraty
5ad42d0f47 Add st_mtime, st_ino and st_dev for ufs_stat
Differential Revision:	D15064
2018-06-09 02:41:51 +00:00
Ed Maste
d8ba45e213 Revert r313780 (UFS_ prefix) 2018-03-17 12:59:55 +00:00
Ed Maste
1e2b9afca9 Prefix UFS symbols with UFS_ to reduce namespace pollution
Followup to r313780.  Also prefix ext2's and nandfs's versions with
EXT2_ and NANDFS_.

Reported by:	kib
Reviewed by:	kib, mckusick
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D9623
2018-03-17 01:48:27 +00:00
Kirk McKusick
efbf396426 This change is some refactoring of Mark Johnston's changes in r329375
to fix the memory leak that I introduced in r328426. Instead of
trying to clear up the possible memory leak in all the clients, I
ensure that it gets cleaned up in the source (e.g., ffs_sbget ensures
that memory is always freed if it returns an error).

The original change in r328426 was a bit sparse in its description.
So I am expanding on its description here (thanks cem@ and rgrimes@
for your encouragement for my longer commit messages).

In preparation for adding check hashing to superblocks, r328426 is
a refactoring of the code to get the reading/writing of the superblock
into one place. Unlike the cylinder group reading/writing which
ends up in two places (ffs_getcg/ffs_geom_strategy in the kernel
and cgget/cgput in libufs), I have the core superblock functions
just in the kernel (ffs_sbfetch/ffs_sbput in ffs_subr.c which is
already imported into utilities like fsck_ffs as well as libufs to
implement sbget/sbput). The ffs_sbfetch and ffs_sbput functions
take a function pointer to do the actual I/O for which there are
four variants:

    ffs_use_bread / ffs_use_bwrite for the in-kernel filesystem

    g_use_g_read_data / g_use_g_write_data for kernel geom clients

    ufs_use_sa_read for the standalone code (stand/libsa/ufs.c
	but not stand/libsa/ufsread.c which is size constrained)

    use_pread / use_pwrite for libufs

Uses of these interfaces are in the UFS filesystem, geoms journal &
label, libsa changes, and libufs. They also permeate out into the
filesystem utilities fsck_ffs, newfs, growfs, clri, dump, quotacheck,
fsirand, fstyp, and quot. Some of these utilities should probably be
converted to directly use libufs (like dumpfs was for example), but
there does not seem to be much win in doing so.

Tested by: Peter Holm (pho@)
2018-03-02 04:34:53 +00:00
Conrad Meyer
2e7e6fbce5 libsa: Const-ify buffer argument of write(2) analog
Reported by:	kevans
Reviewed by:	delphij, eadler, imp, kevans
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D14482
2018-02-23 20:18:09 +00:00
Mark Johnston
16759360d4 Fix a memory leak introduced in r328426.
ffs_sbget() may return a superblock buffer even if it fails, so the
caller must be prepared to free it in this case. Moreover, when tasting
alternate superblock locations in a loop, ffs_sbget()'s readfunc
callback must free the previously allocated buffer.

Reported and tested by:	pho
Reviewed by:		kib (previous version)
Differential Revision:	https://reviews.freebsd.org/D14390
2018-02-16 15:41:03 +00:00
Kirk McKusick
dffce2150e Refactoring of reading and writing of the UFS/FFS superblock.
Specifically reading is done if ffs_sbget() and writing is done
in ffs_sbput(). These functions are exported to libufs via the
sbget() and sbput() functions which then used in the various
filesystem utilities. This work is in preparation for adding
subperblock check hashes.

No functional change intended.

Reviewed by: kib
2018-01-26 00:58:32 +00:00
Warner Losh
ca987d4641 Move sys/boot to stand. Fix all references to new location
Sponsored by:	Netflix
2017-11-14 23:02:19 +00:00