Emulated for SMB3 and later via server side copy
and setsize. Eventually this could be compounded.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Improves directory metadata caching
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Needed for the final patch in the directory caching series
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

and clear the timestamp when we receive a lease break.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Needed for subsequent patches in the directory caching
series.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

We need to hold both a reference for the root/superblock as well as the directory that we
are caching. We need to drop these references before we call kill_anon_sb().

At this point, the root and the cached dentries are always the same but this will change
once we start caching other directories as well.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

And use this to only allow to take out a shared handle once the mount has completed and the
sb becomes available.
This will become important in follow up patches where we will start holding a reference to the
directory dentry for the shared handle during the lifetime of the handle.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

These functions will eventually be used to cache any directory, not just the root
so change the names.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Move the check for the directory path into the open_shroot() function
but still fail for any non-root directories.
This is preparation for later when we will start using the cache also
for other directories than the root.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

instead of doing it in the callsites for open_shroot.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

The cost is that we might need to flip '/' to '\\' in more than
just the prefix.  Needs profiling, but I suspect that we won't
get slowdown on that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steve French <stfrench@microsoft.com>

build_path_from_dentry() open-codes dentry_path_raw().  The reason
we can't use dentry_path_raw() in there (and postprocess the
result as needed) is that the callers of build_path_from_dentry()
expect that the object to be freed on cleanup and the string to
be used are at the same address.  That's painful, since the path
is naturally built end-to-beginning - we start at the leaf and
go through the ancestors, accumulating the pathname.

Life would be easier if we left the buffer allocation to callers.
It wouldn't be exact-sized buffer, but none of the callers keep
the result for long - it's always freed before the caller returns.
So there's no need to do exact-sized allocation; better use
__getname()/__putname(), same as we do for pathname arguments
of syscalls.  What's more, there's no need to do allocation under
spinlocks, so GFP_ATOMIC is not needed.

Next patch will replace the open-coded dentry_path_raw() (in
build_path_from_dentry_optional_prefix()) with calling the real
thing.  This patch only introduces wrappers for allocating/freeing
the buffers and switches to new calling conventions:
	build_path_from_dentry(dentry, buf)
expects buf to be address of a page-sized object or NULL,
return value is a pathname built inside that buffer on success,
ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if
the pathname won't fit into page.  Note that we don't need to
check for failure when allocating the buffer in the caller -
build_path_from_dentry() will do the right thing.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steve French <stfrench@microsoft.com>

... and adjust the callers.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steve French <stfrench@microsoft.com>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steve French <stfrench@microsoft.com>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steve French <stfrench@microsoft.com>

As it is, it takes const char * and, in some cases, stores it in
caller's variable that is plain char *.  Fortunately, none of the
callers actually proceeded to modify the string via now-non-const
alias, but that's trouble waiting to happen.

It's easy to do properly, anyway...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steve French <stfrench@microsoft.com>

strndup(s, strlen(s)) is a highly unidiomatic way to spell strdup(s);
it's *NOT* safer in any way, since strlen() is just as sensitive to
NUL-termination as strdup() is.

strndup() is for situations when you need a copy of a known-sized
substring, not a magic security juju to drive the bad spirits away.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steve French <stfrench@microsoft.com>

Protocol has been extended for additional compression headers.
See MS-SMB2 section 2.2.42
Signed-off-by: Steve French <stfrench@microsoft.com>

While reviewing a patch clarifying locks and locking hierarchy I
realized some locks were unused.

This commit removes old data and code that isn't actually used
anywhere, or hidden in ifdefs which cannot be enabled from the kernel
config.

* The uid/gid trees and associated locks are left-overs from when
  uid/sid mapping had an extra caching layer on top of the keyring and
  are now unused.
  See commit faa65f07 ("cifs: simplify id_to_sid and sid_to_id mapping code")
  from 2012.

* cifs_oplock_break_ops is a left-over from when slow_work was remplaced
  by regular workqueue and is now unused.
  See commit 9b646972 ("cifs: use workqueue instead of slow-work")
  from 2010.

* CIFSSMBSetAttrLegacy is SMB1 cruft dealing with some legacy
  NT4/Win9x behaviour.

* Remove CONFIG_CIFS_DNOTIFY_EXPERIMENTAL left-overs. This was already
  partially removed in 392e1c5d ("cifs: rename and clarify CIFS_ASYNC_OP and CIFS_NO_RESP")
  from 2019. Kill it completely.

* Another candidate that was considered but spared is
  CONFIG_CIFS_NFSD_EXPORT which has an empty implementation and cannot
  be enabled by a config option (although it is listed but disabled with
  "BROKEN" as a dep). It's unclear whether this could even function
  today in its current form but it has it's own .c file and Kconfig
  entry which is a bit more involved to remove and might make a come
  back?
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

There is a regular need in the kernel to provide a way to declare having
a dynamically sized set of trailing elements in a structure. Kernel code
should always use “flexible array members”[1] for these cases. The older
style of one-element or zero-length arrays should no longer be used[2].

Also, this helps with the ongoing efforts to enable -Warray-bounds by
fixing the following warning:

  CC [M]  fs/cifs/cifssmb.o
fs/cifs/cifssmb.c: In function ‘CIFSFindNext’:
fs/cifs/cifssmb.c:4636:23: warning: array subscript 1 is above array bounds of ‘char[1]’ [-Warray-bounds]
 4636 |   pSMB->ResumeFileName[name_len+1] = 0;
      |   ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.10/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/109Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

struct cifs_writedata is declared twice.
One is declared at 209th line.
And struct cifs_writedata is defined blew.
The declaration hear is not needed. Remove the duplicate.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Add missing documentation for open_files and dfscache /proc files.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>

This commit doesn't change the logic of SWN.

Add dummy implementation of SWN functions when SWN is disabled instead
of using ifdef sections.

The dummy functions get optimized out, this leads to clearer code and
compile time type-checking regardless of config options with no
runtime penalty.

Leave the simple ifdefs section as-is.

A single bitfield (bool foo:1) on its own will use up one int. Move
tcon->use_witness out of ifdefs with the other tcon bitfields.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Samuel Cabrero <scabrero@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>

[MS-SMB2] protocol specification was recently updated to include
new flags, new negotiate context and some minor changes to fields.
Update smb2pdu.h structure definitions to match the newest version
of the protocol specification.  Updates to the compression context
values will be in a followon patch.
Signed-off-by: Steve French <stfrench@microsoft.com>

A few of the semaphores had been removed, and one additional one
needed to be noted in the comments.
Signed-off-by: Steve French <stfrench@microsoft.com>

Fix the following gcc warning:

fs/cifs/cifsacl.c:1097:8: warning: variable ‘nmode’ set but not used
[-Wunused-but-set-variable].
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

secuirty -> security
Signed-off-by: jack1.li_cp <liliu1@yulong.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Merge tag 'perf-tools-fixes-for-v5.12-2021-04-25' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Fix potential NULL pointer dereference in the auxtrace option parser

 - Fix access to PID in an array when setting a PID filter in 'perf ftrace'

 - Fix error return code in the 'perf data' tool and in maps__clone(),
   found using a static analysis tool from Huawei

* tag 'perf-tools-fixes-for-v5.12-2021-04-25' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  perf map: Fix error return code in maps__clone()
  perf ftrace: Fix access to pid in array when setting a pid filter
  perf auxtrace: Fix potential NULL pointer dereference
  perf data: Fix error return code in perf_data__create_dir()

Pull x86 perf fixes from Borislav Petkov:

 - Fix Broadwell Xeon's stepping in the PEBS isolation table of CPUs

 - Fix a panic when initializing perf uncore machinery on Haswell and
   Broadwell servers

* tag 'perf_urgent_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/kvm: Fix Broadwell Xeon stepping in isolation_ucodes[]
  perf/x86/intel/uncore: Remove uncore extra PCI dev HSWEP_PCI_PCU_3

Pull locking fix from Borislav Petkov:
 "Fix ordering in the queued writer lock's slowpath"

* tag 'locking_urgent_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/qrwlock: Fix ordering in queued_write_lock_slowpath()

Pull scheduler fix from Borislav Petkov:
 "Fix a typo in a macro ifdeffery"

* tag 'sched_urgent_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  preempt/dynamic: Fix typo in macro conditional statement

Pull x86 fix from Borislav Petkov:
 "Fix an out-of-bounds memory access when setting up a crash kernel with
  kexec"

* tag 'x86_urgent_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/crash: Fix crash_setup_memmap_entries() out-of-bounds access

Pull kvm fix from Paolo Bonzini:
 "Fix SRCU bug introduced in the merge window"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86/xen: Take srcu lock when accessing kvm_memslots()

This reverts commit 0c85a7e8.

The games with 'rm' are on (two separate instances) of a local variable,
and make no difference.

Quoting Aditya Pakki:
 "I was the author of the patch and it was the cause of the giant UMN
  revert.

  The patch is garbage and I was unaware of the steps involved in
  retracting it. I *believed* the maintainers would pull it, given it
  was already under Greg's list. The patch does not introduce any bugs
  but is pointless and is stupid. I accept my incompetence and for not
  requesting a revert earlier."

Link: https://lwn.net/Articles/854319/Requested-by: Aditya Pakki <pakki001@umn.edu>
Cc: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull pin control fixes from Linus Walleij:
 "Late pin control fixes, would have been in the main pull request
  normally but hey I got lucky and we got another week to polish up
  v5.12 so here we go.

  One driver fix and one making the core debugfs work:

   - Fix the number of pins in the community of the Intel Lewisburg SoC

   - Show pin numbers for controllers with base = 0 in the new debugfs
     feature"

* tag 'pinctrl-v5.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: core: Show pin numbers for the controllers with base = 0
  pinctrl: lewisburg: Update number of pins in community

Merge misc fixes from Andrew Morton:
 "5 patches.

  Subsystems affected by this patch series: coda, overlayfs, and
  mm (pagecache and memcg)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  tools/cgroup/slabinfo.py: updated to work on current kernel
  mm/filemap: fix mapping_seek_hole_data on THP & 32-bit
  mm/filemap: fix find_lock_entries hang on 32-bit THP
  ovl: fix reference counting in ovl_mmap error path
  coda: fix reference counting in coda_file_mmap error path

Pull block fix from Jens Axboe:
 "A single fix for a behavioral regression in this series, when
  re-reading the partition table with partitions open"

* tag 'block-5.12-2021-04-23' of git://git.kernel.dk/linux-block:
  block: return -EBUSY when there are open partitions in blkdev_reread_part

slabinfo.py script does not work with actual kernel version.

First, it was unable to recognise SLUB susbsytem, and when I specified
it manually it failed again with

  AttributeError: 'struct page' has no member 'obj_cgroups'

.. and then again with

  File "tools/cgroup/memcg_slabinfo.py", line 221, in main
    memcg.kmem_caches.address_of_(),
  AttributeError: 'struct mem_cgroup' has no member 'kmem_caches'

Link: https://lkml.kernel.org/r/cec1a75e-43b4-3d64-2084-d9f98fda037f@virtuozzo.comSigned-off-by: Vasily Averin <vvs@virtuozzo.com>
Tested-by: Roman Gushchin <guro@fb.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

No problem on 64-bit, or without huge pages, but xfstests generic/285
and other SEEK_HOLE/SEEK_DATA tests have regressed on huge tmpfs, and on
32-bit architectures, with the new mapping_seek_hole_data().  Several
different bugs turned out to need fixing.

u64 cast to stop losing bits when converting unsigned long to loff_t
(and let's use shifts throughout, rather than mixed with * and /).

Use round_up() when advancing pos, to stop assuming that pos was already
THP-aligned when advancing it by THP-size.  (This use of round_up()
assumes that any THP has THP-aligned index: true at present and true
going forward, but could be recoded to avoid the assumption.)

Use xas_set() when iterating away from a THP, so that xa_index stays in
synch with start, instead of drifting away to return bogus offset.

Check start against end to avoid wrapping 32-bit xa_index to 0 (and to
handle these additional cases, seek_data or not, it's easier to break
the loop than goto: so rearrange exit from the function).

[hughd@google.com: remove unneeded u64 casts, per Matthew]
  Link: https://lkml.kernel.org/r/alpine.LSU.2.11.2104221347240.1170@eggly.anvils

Link: https://lkml.kernel.org/r/alpine.LSU.2.11.2104211737410.3299@eggly.anvils
Fixes: 41139aa4 ("mm/filemap: add mapping_seek_hole_data")
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>