manual page:
There is no need to call arc4random_stir() before using
arc4random() functions family, since they automatically
initialize themselves.
No objection: des
MFC after: 2 weeks
running time for a full fsck. It also reduces the random access time
for large files and speeds the traversal time for directory tree walks.
The key idea is to reserve a small area in each cylinder group
immediately following the inode blocks for the use of metadata,
specifically indirect blocks and directory contents. The new policy
is to preferentially place metadata in the metadata area and
everything else in the blocks that follow the metadata area.
The size of this area can be set when creating a filesystem using
newfs(8) or changed in an existing filesystem using tunefs(8).
Both utilities use the `-k held-for-metadata-blocks' option to
specify the amount of space to be held for metadata blocks in each
cylinder group. By default, newfs(8) sets this area to half of
minfree (typically 4% of the data area).
This work was inspired by a paper presented at Usenix's FAST '13:
www.usenix.org/conference/fast13/ffsck-fast-file-system-checker
Details of this implementation appears in the April 2013 of ;login:
www.usenix.org/publications/login/april-2013-volume-38-number-2.
A copy of the April 2013 ;login: paper can also be downloaded
from: www.mckusick.com/publications/faster_fsck.pdf.
Reviewed by: kib
Tested by: Peter Holm
MFC after: 4 weeks
extended using growfs(8). The problem here is that geom_label checks if
the filesystem size recorded in UFS superblock is equal to the provider
(i.e. device) size. This check cannot be removed due to backward
compatibility. On the other hand, in most cases growfs(8) cannot set
fs_size in the superblock to match the provider size, because, differently
from newfs(8), it cannot recompute cylinder group sizes.
To fix this problem, add another superblock field, fs_providersize, used
only for this purpose. The geom_label(4) will attach if either fs_size
(filesystem created with newfs(8)) or fs_providersize (filesystem expanded
using growfs(8)) matches the device size.
PR: kern/165962
Reviewed by: mckusick
Sponsored by: FreeBSD Foundation
the now default 32K/4K filesystem the same as the number of inodes in
the previously default 16K/2K filesystem.
PR: bin/16265
Reported by: Olivier Cochard-Labbe <olivier@cochard.me>
MFC: 4 weeks (9 is the only affected branch)
These tools declare global variables without using the static keyword,
even though their use is limited to a single C-file, or without placing
an extern declaration of them in the proper header file.
16K to 32K and the default fragment size from 2K to 4K.
The rational is that most disks are now running with 4K
sectors. While they can (slowly) simulate 512-byte sectors
by doing a read-modify-write, it is desirable to avoid this
functionality. By raising the minimum filesystem allocation
to 4K, the filesystem will never trigger the small sector
emulation.
Also, the growth of disk sizes has lead us to double the
default block size about every ten years. The rise from 8K
to 16K blocks was done in 2001. So, by the 10-year metric,
the time has come for 32K blocks.
Discussed at: May 2011 BSDCan Developer Summit
Reference: http://wiki.freebsd.org/201105DevSummit/FileSystems
This avoids a potentially many-hours-long loop of failed writes if newfs
finds a partially-overwritten superblock (or, for that matter, random
garbage which happens to have superblock magic bytes); on one occasion I
found newfs trying to zero 800 million superblocks on a 50 MB disk.
Reviewed by: mckusick
MFC after: 1 week
include sys/time.h instead of time.h. This include is incorrect as
per the manpages for the APIs and the POSIX definitions. This commit
replaces sys/time.h where necessary with time.h.
The commit also includes some minor style(9) header fixup in newfs.
This commit is part of a larger effort by Garrett Cooper started in
//depot/user/gcooper/posix-conformance-work/ -- to make FreeBSD more
POSIX compliant.
Submitted by: Garrett Cooper yanegomi at gmail dot com
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
size or size-like argument. I.e. "-s 32k" instead of "-s 32768".
Size parsing function has been shamelessly stolen from the truncate(1).
I'm sure many sysadmins out there will appreciate this small
improvement.
MFC after: 1 week
inodes by cutting back on the number of inodes per cylinder group if
necessary to stay under the limit. For a default (16K block) file
system, this limit begins to take effect for file systems above 32Tb.
This fix is in addition to -r203763 which corrected a problem in the
kernel that treated large inode numbers as negative rather than unsigned.
For a default (16K block) file system, this bug began to show up at a
file system size above about 16Tb.
Reported by: Scott Burns, John Kilburg, Bruce Evans
Followup by: Jeff Roberson
PR: 133980
MFC after: 2 weeks
it was before -- the check is only made when getdisklabel()
returns valid info.
On passing, use MAXPARTITIONS to identify the max partition number,
instead of the hardwired 'h'
MFC after: 4 weeks
want to prepare disk images for emulators (though 'makefs' in port
can do something similar).
This relies on:
+ minor changes to pass the consistency checks even when working on a file;
+ an additional option, '-p partition' , to specify the disk partition to
initialize;
+ some changes on the I/O routines to deal with partition offsets.
The latter was a bit tricky to implement, see the details in newfs.h:
in newfs, I/O is done through libufs which assumes that the file
descriptor refers to the whole partition. Introducing support for
the offset in libufs would require a non-backward compatible change
in the library, to be dealt with a version bump or with symbol
versioning.
I felt both approaches to be overkill for this specific application,
especially because there might be other changes to libufs that might
become necessary in the near future.
So I used the following trick:
- read access is always done by calling bread() directly, so we just add
the offset in the (few) places that call bread();
- write access is done through bwrite() and sbwrite(), which in turn
calls bwrite(). To avoid rewriting sbwrite(), we supply our own version
of bwrite() here, which takes precedence over the version in libufs.
MFC after: 4 weeks
replace this with vinum.4, but that's the kernel interface manual, which
is not appropriate in my understanding. I think that gvinum is a suitable
replacement for this.
PR: docs/121938
Submitted by: "Federico" <federicogalvezdurand at yahoo dot com>
MFC after: 3 days
Implement -E option which will erase the filesystem sectors before
making the new filesystem. Reserved space in front of the superblock
(bootcode) is not erased.
NB: Erasing can take as long time as writing every sector sequentially.
This is relevant for all flash based disks which use wearlevelling.
return -1 on error while any other return value from it can
indicate success. (See RETURN VALUE in our ioctl(2) manpage
and the POSIX spec.)
- Avoid assumptions about the state of the data buffer after
ioctl(2) failure.
Add a new option to newfs(8), -r, to specify reserved space at the
end of the device. It can be useful, e.g., when the device is to
become a member of a gmirror array later w/o losing the file system
on it.
Document the new option in the manpage.
While I'm here, improve error handling for -s option, which is
syntactically similar to -r; and document the fact that -s0 selects
the default fs size explicitly, which can be useful, e.g., in a
menu-based wrapper around newfs(8) requiring some value be entered
for the fs size.
Also fix a small typo in the help line for -s (missing space).
Idea and initial implementation by: marck
Discussed on: -fs
Critical review by: bde
Tested with: cmp(1)
affect the largest file size that is allowed by the file system.
On the other hand, when creating a snapshot, the snapshot file will
appear as it is as big as the file system itself. Hence we will not
be able to create a file system on large file systems with small
block sizes.
Add a warning about this, and gives some hints to correct the issue.
Reviewed by: mckusick
MFC After: 1 week
the new filesystem. This is intended for memory and vnode filesystems
that will never be fsck'ed or dumped.
Obtained from: St. Bernard Software RAPID
MFC after: 2 weeks
