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Restore backward compatibility of UFS2 with previous NetBSD releases by disabling support in UFS2 for extended attributes (including ACLs). Add a new variant of UFS2 called "UFS2ea" that does support extended attributes. Add new fsck_ffs operations "-c ea" and "-c no-ea" to convert file systems from UFS2 to UFS2ea and vice-versa (both of which delete all existing extended attributes in the process).
Sync with HEAD
add NO_IOBUF_ALIGNED to not pull aligned_alloc() for really constrained boot media
Sync with HEAD
Sync with HEAD
__empty -> __nothing
switch to __empty
Add smaller versions of fsck_ffs(8) and newfs(8) for install media, where support for Endian-Independent FFS and Apple UFS is disabled unless FFS_EI=1 and APPLE_UFS=1 are added to CRUNCHENV, respectively. This reduces the size of ramdisk image for atari by over 15KB. Thanks tsutsui and christos for their useful comments.
merge the bouyer-quota2 branch. This adds a new on-disk format to store disk quota usage and limits, integrated with ffs metadata. Usage is checked by fsck_ffs (no more quotacheck) and is covered by the WAPBL journal. Enabled with kernel option QUOTA2 (added where QUOTA was enabled in kernel config files), turned on with tunefs(8) on a per-filesystem basis. mount_mfs(8) can also turn quotas on. See http://mail-index.netbsd.org/tech-kern/2011/02/19/msg010025.html for details.
Snapshot of work in progress on a modernised disk quota system:
- new quotactl syscall (versionned for backward compat), which takes
as parameter a path to a mount point, and a prop_dictionary
(in plistref format) describing commands and arguments.
For each command, status and data are returned as a prop_dictionary.
quota commands features will be added to take advantage of this,
exporting quota data or getting quota commands as plists.
- new on disk-format storage (all 64bit wide), integrated to metadata for
ffs (and playing nicely with wapbl).
Quotas are enabled on a ffs filesystem via superblock flags.
tunefs(8) can enable or disable quotas.
On a quota-enabled filesystem, fsck_ffs(8) will track per-uid/gid
block and inode usages, and will check and update quotas in Pass 6.
quota usage and limits are stored in unliked files (one for users,
one for groups)l fsck_ffs(8) will create the files if needed, or
free them if needed. This means that after enabling or disabling
quotas on a filesystem; a fsck_ffs(8) run is required.
quotacheck(8) is not needed any more, on a unclean shutdown
fsck or journal replay will take care of fixing quotas.
newfs(8) can create a ready-to-mount quota-enabled filesystem
(superblock flags are set and quota inodes are created).
Other new features or semantic changes:
- default quota datas, applied to users or groups which don't already
have a quota entry
- per-user/group grace time (instead of a filesystem global one)
- 0 really means "nothing allowed at all", not "no limit".
If you want "no limit", set the limit to UQUAD_MAX (tools will
understand "unlimited" and "-")
A quota file is structured as follow:
it starts with a header, containing a few per-filesystem values,
and the default quota limits.
Quota entries are linked together as a simple list, each entry has a
pointer (as an offset withing the file) to the next.
The header has a pointer to a list of free quota entries, and
a hash table of in-use entries. The size of the hash table depends
on the filesystem block size (header+hash table should fit in the
first block). The file is not sparse and is a multiple of
filesystem block size (when the free quota entry list is empty a new
filesystem block is allocated). quota entries to not cross
filesystem block boundaries.
In memory, the kernel keeps a cache of recently used quota entries
as a reference to the block number, and offset withing the block.
The quota entry itself is keept in the buf cache.
fsck_ffs(8), tunefs(8) and newfs(8) supports are completed (with
related atf tests :)
The kernel can update disk usage and report it via quotactl(2).
Todo: enforce quotas limits (limits are not checked by kernel yet)
update repquota, edquota and rpc.rquotad to the new world
implement compat_50_quotactl ioctl.
update quotactl(2) man page
fsck_ffs required fixes so that allocating new blocks or inodes will
properly update the superblock and cg sumaries. This was not an issue up
to now because superblock and cg sumaries check happened last, but now
allocations or frees can happen in pass 6.
Remove 3rd and 4th clauses in christos' license. OK christos.
- Deal with wedges and the new disk geometry structures, instead of using
struct disklabel.
Functionality lost:
1. struct disklabel used to be updated to contain bsize, fsize, cpg.
This information was used to locate the alternative superblock in
the filesystem if the primary superblock was corrupted. We need
to find a new place to store this information if we need this
functionality.
2. On vax SMD drives that contained bad sector lists, the newfs program
knew how to get the offset and skip to the correct location in order
to place the label.
Add a '-V verbose' option that controls the amount of info writen to stdout.
0: No output. Default for mount_mfs unless -N specified
1: Output size of partition and cylinder groups.
2: Follow with a progress-bar line of dots (scaled to finish at RH margin)
3: Include a single line of alternate suberblock addresses before progress
bar. Default for newfs.
4: Output lots of lines of alternate superblock numbers that scroll madly
up the screen.
If -N given, newfs/mount_mfs exits before displaying any progress bar.
Output constrained (almost always) to 1 column less than the terminal width.
Make mkfs -N work again (was trying to read filesystem). Correct calculation of number of inodes from density for small filesystems. Add a '-n inodes' option so that the desired number of inodes can be explicitly given - init needs this for mfs /dev, -i density is too crude.
Ensure the area between the end of the main superblock and the start of the first alternate superblock is zerod. Removes any possibility of any programs using a trully out of date alternate superblock if a filesystem is remade with a larger block size.
Add support for UFS2. UFS2 is an enhanced FFS, adding support for 64 bit block pointers, extended attribute storage, and a few other things. This commit does not yet include the code to manipulate the extended storage (for e.g. ACLs), this will be done later. Originally written by Kirk McKusick and Network Associates Laboratories for FreeBSD.
Add support for the Apple UFS variation on ffs This is the bulk of PR #17345 The general approach is to use a run time deteriminable value for DIRBLKSIZ. Additional allowances are included for using MAXSYMLINKLEN with FS_42INODEFMT and a shift in the cylinder group cluster summary count array. Support is added for managing the Apple UFS volume label.
Add the ability for the user, group and permissions of an MFS to be set
on the command line with the -u, -g and -p options respectively.
The old malloc() replacement (and related functions) didn't work with
the libc get{pw,gr}nam() functions so it was removed and a separate
memory allocation function added that is only called to allocate the
space for the MFS file system.
Also use a table for the usage flags instead of multiple fprintf()'s
with "if (mfs)" checks sprinkled through.
Pull up revision 1.6 (requested by lukem): Pull in enhanced ffs_dirpref() algorithm, which provides a substantial performance improvement through better locality between parent/child directories and their files, and by easing the pressure on the buffer cache for metadata operations.
Pull up revision 1.5 (requested by lukem): Replace unused fs_headswitch/trkseek with fs_id.
Pull up revisions 1.2-1.3 (requested by lukem): Jumbo pullup for newfs: o convert to ANSI function prototypes o move external variables to extern.h
Incorporate the enhanced ffs_dirpref() by Grigoriy Orlov, as found in
FreeBSD (three commits; the initial work, man page updates, and a fix
to ffs_reload()), with the following differences:
- Be consistent between newfs(8) and tunefs(8) as to the options which
set and control the tuning parameters for this work (avgfilesize & avgfpdir)
- Use u_int16_t instead of u_int8_t to keep track of the number of
contiguous directories (suggested by Chuck Silvers)
- Work within our FFS_EI framework
- Ensure that fs->fs_maxclusters and fs->fs_contigdirs don't point to
the same area of memory
The new algorithm has a marked performance increase, especially when
performing tasks such as untarring pkgsrc.tar.gz, etc.
The original FreeBSD commit messages are attached:
=====
mckusick 2001/04/10 01:39:00 PDT
Directory layout preference improvements from Grigoriy Orlov <gluk@ptci.ru>.
His description of the problem and solution follow. My own tests show
speedups on typical filesystem intensive workloads of 5% to 12% which
is very impressive considering the small amount of code change involved.
------
One day I noticed that some file operations run much faster on
small file systems then on big ones. I've looked at the ffs
algorithms, thought about them, and redesigned the dirpref algorithm.
First I want to describe the results of my tests. These results are old
and I have improved the algorithm after these tests were done. Nevertheless
they show how big the perfomance speedup may be. I have done two file/directory
intensive tests on a two OpenBSD systems with old and new dirpref algorithm.
The first test is "tar -xzf ports.tar.gz", the second is "rm -rf ports".
The ports.tar.gz file is the ports collection from the OpenBSD 2.8 release.
It contains 6596 directories and 13868 files. The test systems are:
1. Celeron-450, 128Mb, two IDE drives, the system at wd0, file system for
test is at wd1. Size of test file system is 8 Gb, number of cg=991,
size of cg is 8m, block size = 8k, fragment size = 1k OpenBSD-current
from Dec 2000 with BUFCACHEPERCENT=35
2. PIII-600, 128Mb, two IBM DTLA-307045 IDE drives at i815e, the system
at wd0, file system for test is at wd1. Size of test file system is 40 Gb,
number of cg=5324, size of cg is 8m, block size = 8k, fragment size = 1k
OpenBSD-current from Dec 2000 with BUFCACHEPERCENT=50
You can get more info about the test systems and methods at:
http://www.ptci.ru/gluk/dirpref/old/dirpref.html
Test Results
tar -xzf ports.tar.gz rm -rf ports
mode old dirpref new dirpref speedup old dirprefnew dirpref speedup
First system
normal 667 472 1.41 477 331 1.44
async 285 144 1.98 130 14 9.29
sync 768 616 1.25 477 334 1.43
softdep 413 252 1.64 241 38 6.34
Second system
normal 329 81 4.06 263.5 93.5 2.81
async 302 25.7 11.75 112 2.26 49.56
sync 281 57.0 4.93 263 90.5 2.9
softdep 341 40.6 8.4 284 4.76 59.66
"old dirpref" and "new dirpref" columns give a test time in seconds.
speedup - speed increasement in times, ie. old dirpref / new dirpref.
------
Algorithm description
The old dirpref algorithm is described in comments:
/*
* Find a cylinder to place a directory.
*
* The policy implemented by this algorithm is to select from
* among those cylinder groups with above the average number of
* free inodes, the one with the smallest number of directories.
*/
A new directory is allocated in a different cylinder groups than its
parent directory resulting in a directory tree that is spreaded across
all the cylinder groups. This spreading out results in a non-optimal
access to the directories and files. When we have a small filesystem
it is not a problem but when the filesystem is big then perfomance
degradation becomes very apparent.
What I mean by a big file system ?
1. A big filesystem is a filesystem which occupy 20-30 or more percent
of total drive space, i.e. first and last cylinder are physically
located relatively far from each other.
2. It has a relatively large number of cylinder groups, for example
more cylinder groups than 50% of the buffers in the buffer cache.
The first results in long access times, while the second results in
many buffers being used by metadata operations. Such operations use
cylinder group blocks and on-disk inode blocks. The cylinder group
block (fs->fs_cblkno) contains struct cg, inode and block bit maps.
It is 2k in size for the default filesystem parameters. If new and
parent directories are located in different cylinder groups then the
system performs more input/output operations and uses more buffers.
On filesystems with many cylinder groups, lots of cache buffers are
used for metadata operations.
My solution for this problem is very simple. I allocate many directories
in one cylinder group. I also do some things, so that the new allocation
method does not cause excessive fragmentation and all directory inodes
will not be located at a location far from its file's inodes and data.
The algorithm is:
/*
* Find a cylinder group to place a directory.
*
* The policy implemented by this algorithm is to allocate a
* directory inode in the same cylinder group as its parent
* directory, but also to reserve space for its files inodes
* and data. Restrict the number of directories which may be
* allocated one after another in the same cylinder group
* without intervening allocation of files.
*
* If we allocate a first level directory then force allocation
* in another cylinder group.
*/
My early versions of dirpref give me a good results for a wide range of
file operations and different filesystem capacities except one case:
those applications that create their entire directory structure first
and only later fill this structure with files.
My solution for such and similar cases is to limit a number of
directories which may be created one after another in the same cylinder
group without intervening file creations. For this purpose, I allocate
an array of counters at mount time. This array is linked to the superblock
fs->fs_contigdirs[cg]. Each time a directory is created the counter
increases and each time a file is created the counter decreases. A 60Gb
filesystem with 8mb/cg requires 10kb of memory for the counters array.
The maxcontigdirs is a maximum number of directories which may be created
without an intervening file creation. I found in my tests that the best
performance occurs when I restrict the number of directories in one cylinder
group such that all its files may be located in the same cylinder group.
There may be some deterioration in performance if all the file inodes
are in the same cylinder group as its containing directory, but their
data partially resides in a different cylinder group. The maxcontigdirs
value is calculated to try to prevent this condition. Since there is
no way to know how many files and directories will be allocated later
I added two optimization parameters in superblock/tunefs. They are:
int32_t fs_avgfilesize; /* expected average file size */
int32_t fs_avgfpdir; /* expected # of files per directory */
These parameters have reasonable defaults but may be tweeked for special
uses of a filesystem. They are only necessary in rare cases like better
tuning a filesystem being used to store a squid cache.
I have been using this algorithm for about 3 months. I have done
a lot of testing on filesystems with different capacities, average
filesize, average number of files per directory, and so on. I think
this algorithm has no negative impact on filesystem perfomance. It
works better than the default one in all cases. The new dirpref
will greatly improve untarring/removing/coping of big directories,
decrease load on cvs servers and much more. The new dirpref doesn't
speedup a compilation process, but also doesn't slow it down.
Obtained from: Grigoriy Orlov <gluk@ptci.ru>
=====
=====
iedowse 2001/04/23 17:37:17 PDT
Pre-dirpref versions of fsck may zero out the new superblock fields
fs_contigdirs, fs_avgfilesize and fs_avgfpdir. This could cause
panics if these fields were zeroed while a filesystem was mounted
read-only, and then remounted read-write.
Add code to ffs_reload() which copies the fs_contigdirs pointer
from the previous superblock, and reinitialises fs_avgf* if necessary.
Reviewed by: mckusick
=====
=====
nik 2001/04/10 03:36:44 PDT
Add information about the new options to newfs and tunefs which set the
expected average file size and number of files per directory. Could do
with some fleshing out.
=====
some improvements from freebsd/openbsd - replace the unused fs_headswitch and fs_trkseek with fs_id[2], bringing our struct fs closer to that in freebsd & openbsd (& solaris FWIW) - dumpfs: improve warning message when cpc == 0
- constify mkfs()'s first arg - slightly reorder steps in -F image creation
Put extern variable declarations in "extern.h".
ANSIfy.
Fix compiler warnings.