orangefs: saner arguments passing in readdir guts

orangefs_dir_fill() doesn't use oi and dentry arguments at all
do_readdir() gets dentry, uses only dentry->d_inode; it also
gets oi, which is ORANGEFS_I(dentry->d_inode) (i.e. ->d_inode -
constant offset).
orangefs_dir_mode() gets dentry and oi, uses only to pass those
to do_readdir().
orangefs_dir_iterate() uses dentry and oi only to pass those to
orangefs_dir_fill() and orangefs_dir_more().

The only thing it really needs is ->d_inode; moreover, that's
better expressed as file_inode(file) - no need to go through
->f_path.dentry->d_inode.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Orangefs: change iterate to iterate_shared

Changed .iterate to .iterate_shared in orangefs_dir_operations. I
didn't change anything else, there were no xfstests regressions
and no problem with any of my other tests...

Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: stop setting atime on inode dirty

The previous code path was to mark the inode dirty, let
orangefs_inode_dirty set a flag in our private inode, then later during
inode release call orangefs_flush_inode which notices the flag and
writes the atime out.

The code path worked almost identically for mtime, ctime, and mode
except that those flags are set explicitly and not as side effects of
dirty.

Now orangefs_flush_inode is removed. Marking an inode dirty does not
imply an atime update. Any place where flags were set before is now
an explicit call to orangefs_inode_setattr. Since OrangeFS does not
utilize inode writeback, the attribute change should be written out
immediately.

Fixes generic/120.

In namei.c, there are several places where the directory mtime and ctime
are set, but only the mtime is sent to the server. These don't seem
right, but I've left them as is for now.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

orangefs: count directory pieces correctly

A large directory full of differently sized file names triggered this.
Most directories, even very large directories with shorter names, would
be lucky enough to fit in one server response.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: invalidate stored directory on seek

If an application seeks to a position before the point which has been
read, it must want updates which have been made to the directory. So
delete the copy stored in the kernel so it will be fetched again.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: skip forward to the next directory entry if seek is short

If userspace seeks to a position in the stream which is not correct, it
would have returned EIO because the data in the buffer at that offset
would be incorrect. This and the userspace daemon returning a corrupt
directory are indistinguishable.

Now if the data does not look right, skip forward to the next chunk and
try again. The motivation is that if the directory changes, an
application may seek to a position that was valid and no longer is valid.

It is not yet possible for a directory to change.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: remove ORANGEFS_READDIR macros

They are clones of the ORANGEFS_ITERATE macros in use elsewhere. Delete
ORANGEFS_ITERATE_NEXT which is a hack previously used by readdir.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: support very large directories

This works by maintaining a linked list of pages which the directory
has been read into rather than one giant fixed-size buffer.

This replaces code which limits the total directory size to the total
amount that could be returned in one server request. Since filenames
are usually considerably shorter than the maximum, the old code could
usually handle several server requests before running out of space.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: support llseek on directories

This and the previous commit fix xfstests generic/257.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: rewrite readdir to fix several bugs

In the past, readdir assumed that the user buffer will be large enough
that all entries from the server will fit. If this was not true,
entries would be skipped.

Since it works now, request 512 entries rather than 96 per server
operation.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: use %pd/%pD

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

orangefs: remove unused variable

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: don't put readdir slot twice

This was quite an oversight. After a readdir, the module could not be
unloaded, the number of slots is wrong, and memory near the slot bitmap
is possibly corrupt. Oops.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>

orangefs: saner calling conventions for getting a slot

just have it return the slot number or -E... - the caller checks
the sign anyway

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: get rid of readdir_handle_s

no point, really - we couldn't keep those across the calls of
getdents(); it would be too easy to DoS, having all slots exhausted.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

Orangefs: add a new gossip statement

Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: free readdir buffer index before the dir_emit loop

We only need it while the service operation is actually in progress
since it is only used to co-ordinate the client-core's memory use. The
kernel allocates its own space.

Also clean up some comments which mislead the reader into thinking
the readdir buffers are shared memory.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs_readdir_index_put(): get rid of bufmap argument

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

Orangefs: add verification to decode_dirents

Also add comments to decode_dirents and make it more readable.

Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: Fix some more global namespace pollution.

This only changes the names of things, so there is no functional change.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

Orangefs: change pvfs2 filenames to orangefs

Also changed references within source files that referred to
header files whose names had changed.

Signed-off-by: Mike Marshall <hubcap@omnibond.com>

OrangeFS: Change almost all instances of the string PVFS2 to OrangeFS.

OrangeFS was formerly known as PVFS2 and retains the name in many places.

I leave the device /dev/pvfs2-req since this affects userspace.

I leave the filesystem type pvfs2 since this affects userspace. Further
the OrangeFS sysint library reads fstab for an entry of type pvfs2
independently of kernel mounts.

I leave extended attribute keys user.pvfs2 and system.pvfs2 as the
sysint library understands these.

I leave references to userspace binaries still named pvfs2.

I leave the filenames.

Signed-off-by: Yi Liu <yi9@clemson.edu>
[martin@omnibond.com: clairify above constraints and merge]
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: validate the response in decode_dirents()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: get rid of dec_string and enc_string

The latter is never used, the former has one user and would be
better off spelled out right there.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

orangefs: switch decode_dirents() to use of kcalloc()

gets rid of multiplication overflow

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

Orangefs: fix some checkpatch.pl complaints that had creeped in.

Signed-off-by: Mike Marshall <hubcap@omnibond.com>

Orangefs: fix dir_emit code in pvfs2_readdir.

Al Viro glanced at readdir and surmised that getdents
would misbehave the way it was written... and sure enough.

Signed-off-by: Mike Marshall <hubcap@omnibond.com>

Orangefs: address problems found by static checker

Don't check for negative rc from boolean.

Don't pointlessly initialize variables, it short-circuits
gcc's uninitialized variable warnings. And max_new_nr_segs
can never be zero, so don't check for it.

Preserve original kstrdup pointer for freeing later.

Don't check for negative value in unsigned variable.

Signed-off-by: Mike Marshall <hubcap@omnibond.com>

Orangefs: kernel client part 2

Signed-off-by: Mike Marshall <hubcap@omnibond.com>