When the security attribute is present, chkdsk may set a null security id
in the standard attributes, and this should not be considered as an error.
(this partially reverts commit [70e5b1])
This patch changes the algorithm to use hash chains instead of binary
trees, with much stronger hashing. It also introduces useful (for
performance) parameters, such as the "nice match length" and "maximum
search depth", that are similar to those used in other commonly used
compression algorithms such as zlib's DEFLATE implementation.
The speed improvement is very significant, with some loss of compression
rate. The compression rate is still better than then Windows one.
Contributed by Eric Biggers
The new way goes via /sys/dev/block/MAJOR:MINOR to map partitions to
devices and get discard parameters of the parent device. It also ensures
that the partition is aligned to the discard block size.
Contributed by Richard W.M. Jones
fstrim(8) discards unused blocks on a mounted filesystem. It is useful for
solid-state drives (SSDs) and thinly-provisioned storage.
Only trimming the full device (with no option) is supported.
Contributed by Richard W.M. Jones
When Posix ACLs are used, the umask is ignored and the initial permissions
of created files are taken for the parent directory. However the umask
should still be used when the Posix ACLs are not enabled in the mount
options.
Ownership of files should always represent the creator of files.
This fixes a situation, currently disabled, where there is no user
mapping and the owner of the parent directory is used as the owner
of the created file.
When using Windows inheritance, the cacheing of ACLs for files created
within a directory only depended on the directory. Actually it also
depends on the user who creates the file. With the patch, only the ACLs
created by the owner of the directory are cached.
When grouping of users are determined from /etc/group (a compile-time
option not currently used), the groups examined for checking access rights
to a file were wrongly derived from the uid of the file instead of the
uid of the current process.
Since Vista, the standard directory /Users/Public which should be accessed
by any user is actually restricted to a few group of users, among them
the interactive ones. To make this directory accessible without using
the Posix ACLs, all Linux users are considered as interactive.
However, when Posix ACLs are used, users supposed to be interactive have
to be put into a secondary group mapped to the equivalent Windows group.
When using the Windows permission inheritance mode and the current user
has not been mapped, try to derive a reasonable user from the parent
directory.
The Windows-type inheritance of an ACE may imply creating two ACE's : one
for access and one for further inheritance. The conditions for doing so,
and the flags set on created ACE were sometimes wrong.
Note : the rules have been derived from testing multiple situations, but
there still are some gray cases.
Since Vista, Windows defines a /Users/Public directory supposed to be
public, but actually only allowed to a few user categories (interactive,
batch, etc.) This patch makes possible to create equivalent Unix groups
and group users the same way as in Windows. Posix ACLs have to be enabled
for access to /Users/Public to be allowed to several groups.
chkdsk deletes the ACLs when they are bad or when they are not used any
more. This fixes inserting a new ACL after the previously last ACL (or
even all of them) was deleted.
A bug was introduced by commit d2c7d40a2b :
when the beginning of a file was a hole and the runlist span over several
MFT extents, the runlist was not mapped on filling the initial hole.
This lead to a crash when using torrent to download big files.
Windows applies legacy restrictions to file names, so when the option
windows_names is applied, reject the same reserved names, which are
CON, PRN, AUX, NUL, COM1..COM9, and LPT1..LPT9
When the runlist of the data attribute of MFT has to be split across
several extents, the location of each extent has to be known from the
runlist present in previous extents. So, force the first extent into
record 15 to avoid a bad layout.
When a hole in a sparse file was filled, the runlist was fully recomputed.
When a sparse file spans over several MFT extents, this patch leads to
only recompute the runlist from the modified extent to the end.
Erik Larsson
Jean-Pierre André