996d40f91d
over various major releases. Superblock check hashes were added for the 12 release and cylinder-group and inode check hashes will appear in the 13 release. When a disk with a UFS filesystem is writably mounted, the kernel clears the feature flags for anything that it does not support. For example, if a UFS disk from a 12-stable kernel is mounted on an 11-stable system, the 11-stable kernel will clear the flag in the filesystem superblock that indicates that superblock check-hashs are being maintained. Thus if the disk is later moved back to a 12-stable system, the 12-stable system will know to ignore its incorrect check-hash. If the only filesystem modification done on the earlier kernel is to run a utility such as growfs(8) that modifies the superblock but neither updates the check-hash nor clears the feature flag indicating that it does not support the check-hash, the disk will fail to mount if it is moved back to its original newer kernel. This patch moves the code that clears the filesystem feature flags from the mount code (ffs_mountfs()) to the code that reads the superblock (ffs_sbget()). As ffs_sbget() is used by the kernel mount code and is imported into libufs(3), all the filesystem utilities will now also clear these flags when they make modifications to the filesystem. As suggested by John Baldwin, fsck_ffs(8) has been changed to accept and repair bad superblock check-hashes rather than refusing to run. This change allows fsck to recover filesystems that have been impacted by utilities older than those created after this change and is a sensible thing to do in any event. Reported by: John Baldwin (jhb@) MFC after: 2 weeks Sponsored by: Netflix |
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|---|---|---|
| .github/workflows | ||
| bin | ||
| cddl | ||
| contrib | ||
| crypto | ||
| etc | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| rescue | ||
| sbin | ||
| secure | ||
| share | ||
| stand | ||
| sys | ||
| targets | ||
| tests | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| .arcconfig | ||
| .arclint | ||
| .cirrus.yml | ||
| .clang-format | ||
| .gitattributes | ||
| .gitignore | ||
| COPYRIGHT | ||
| LOCKS | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| Makefile.libcompat | ||
| Makefile.sys.inc | ||
| ObsoleteFiles.inc | ||
| README | ||
| README.md | ||
| RELNOTES | ||
| UPDATING | ||
FreeBSD Source:
This is the top level of the FreeBSD source directory. This file
was last revised on:
FreeBSD
FreeBSD is an operating system used to power modern servers, desktops, and embedded platforms. A large community has continually developed it for more than thirty years. Its advanced networking, security, and storage features have made FreeBSD the platform of choice for many of the busiest web sites and most pervasive embedded networking and storage devices.
For copyright information, please see the file COPYRIGHT in this directory. Additional copyright information also exists for some sources in this tree - please see the specific source directories for more information.
The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree. See build(7), config(8), https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html, and https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html for more information, including setting make(1) variables.
Source Roadmap:
bin System/user commands.
cddl Various commands and libraries under the Common Development
and Distribution License.
contrib Packages contributed by 3rd parties.
crypto Cryptography stuff (see crypto/README).
etc Template files for /etc.
gnu Various commands and libraries under the GNU Public License.
Please see gnu/COPYING* for more information.
include System include files.
kerberos5 Kerberos5 (Heimdal) package.
lib System libraries.
libexec System daemons.
release Release building Makefile & associated tools.
rescue Build system for statically linked /rescue utilities.
sbin System commands.
secure Cryptographic libraries and commands.
share Shared resources.
stand Boot loader sources.
sys Kernel sources.
sys/<arch>/conf Kernel configuration files. GENERIC is the configuration
used in release builds. NOTES contains documentation of
all possible entries.
tests Regression tests which can be run by Kyua. See tests/README
for additional information.
tools Utilities for regression testing and miscellaneous tasks.
usr.bin User commands.
usr.sbin System administration commands.
For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see:
https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/current-stable.html