freebsd kernel with SKQ
95c69781b5
Large (60GB) filesystems created using "newfs -U -O 1 -b 65536 -f 8192" show incorrect results from "df" for free and used space when mounted immediately after creation. fsck on the new filesystem (before ever mounting it once) gives a "SUMMARY INFORMATION BAD" error in phase 5. This error hasn't occurred in any runs of fsck immediately after "newfs -U -b 65536 -f 8192" (leaving out the "-O 1" option). Solution: The default UFS1 superblock is located at offset 8K in the filesystem partition; the default UFS2 superblock is located at offset 64K in the filesystem partition. For UFS1 filesystems with a blocksize of 64K, the first alternate superblock resides at 64K which is the the location used for the default UFS2 superblock. By default, the system first checks for a valid superblock at the default location for a UFS2 filoesystem. For a UFS1 filesystem with a blocksize of 64K, there is a valid UFS1 superblock at this location. Thus, even though it is expected to be a backup superblock, the system will use it as its default superblock. So, we have to ensure that all the statistcs on usage are correct in this first alternate superblock as it is the superblock that will actually be used. While tracking down this problem, another limitation of UFS1 became evident. For UFS1, the number of inodes per cylinder group is stored in an int16_t. Thus the maximum number of inodes per cylinder group is limited to 2^15 - 1. This limit can easily be exceeded for block sizes of 32K and above. Thus when building UFS1 filesystems, newfs must limit the number of inodes per cylinder group to 2^15 - 1. Reported by: Guy Helmer<ghelmer@palisadesys.com> Followup by: Bruce Cran <brucec@freebsd.org> PR: 107692 MFC after: 4 weeks |
||
|---|---|---|
| bin | ||
| cddl | ||
| contrib | ||
| crypto | ||
| etc | ||
| games | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| rescue | ||
| sbin | ||
| secure | ||
| share | ||
| sys | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| COPYRIGHT | ||
| LOCKS | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| Makefile.mips | ||
| ObsoleteFiles.inc | ||
| README | ||
| UPDATING | ||
This is the top level of the FreeBSD source directory. This file was last revised on: $FreeBSD$ 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, the most commonly used one being ``world'', which rebuilds and installs everything in the FreeBSD system from the source tree except the kernel, the kernel-modules and the contents of /etc. The ``world'' target should only be used in cases where the source tree has not changed from the currently running version. See: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html for more information, including setting make(1) variables. The ``buildkernel'' and ``installkernel'' targets build and install the kernel and the modules (see below). Please see the top of the Makefile in this directory for more information on the standard build targets and compile-time flags. Building a kernel is a somewhat more involved process, documentation for which can be found at: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html And in the config(8) man page. Note: If you want to build and install the kernel with the ``buildkernel'' and ``installkernel'' targets, you might need to build world before. More information is available in the handbook. The sample kernel configuration files reside in the sys/<arch>/conf sub-directory (assuming that you've installed the kernel sources), the file named GENERIC being the one used to build your initial installation kernel. The file NOTES contains entries and documentation for all possible devices, not just those commonly used. It is the successor of the ancient LINT file, but in contrast to LINT, it is not buildable as a kernel but a pure reference and documentation file. Source Roadmap: --------------- bin System/user commands. contrib Packages contributed by 3rd parties. crypto Cryptography stuff (see crypto/README). etc Template files for /etc. games Amusements. 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. sys Kernel sources. 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: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html