The newcaps has already included the Ls, no need to check it again.
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

CephFS is a bit unlike most other filesystems in that it only
conditionally does buffered I/O based on the caps that it gets from the
MDS. In most cases, unless there is contended access for an inode the
MDS does give Fbc caps to the client, so the unbuffered codepaths are
only infrequently traveled and are difficult to test.

At one time, the "-o sync" mount option would give you this behavior,
but that was removed in commit 7ab9b380 ("ceph: Don't use
ceph-sync-mode for synchronous-fs.").

Add a new mount option to tell the client to ignore Fbc caps when doing
I/O, and to use the synchronous codepaths exclusively, even on
non-O_DIRECT file descriptors. We already have an ioctl that forces this
behavior on a per-file basis, so we can just always set the CEPH_F_SYNC
flag in the file description on such mounts.

Additionally, this patch also changes the client to not request Fbc when
doing direct I/O. We aren't using the cache with O_DIRECT so we don't
have any need for those caps.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Greg Farnum <gfarnum@redhat.com>
Reviewed-by: Venky Shankar <vshankar@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

玮文 胡 reported seeing the WARN_RATELIMIT pop when writing to an
inode that had been transplanted into the stray dir. The client was
trying to look up the quotarealm info from the parent and that tripped
the warning.

Change the ceph_vino_is_reserved helper to not throw a warning for
MDS stray directories (0x100 - 0x1ff), only for reserved dirs that
are not in that range.

Also, fix ceph_has_realms_with_quotas to return false when encountering
a reserved inode.

URL: https://tracker.ceph.com/issues/53180Reported-by: Hu Weiwen <sehuww@mail.scut.edu.cn>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Luis Henriques <lhenriques@suse.de>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

This pops every second and isn't very useful.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Don't populate the const array spaces on the stack but make it static
const and make the pointer an array to remove a dereference. Shrinks
object code a little too.  Also clean up intent, currently it is spaces
and should be a tab.
Signed-off-by: Colin Ian King <colin.i.king@googlemail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Problem:
The statfs reports incorrect free/available space for quota less then
CEPH_BLOCK size (4M).

Solution:
For quota less than CEPH_BLOCK size, smaller block size of 4K is used.
But if quota is less than 4K, it is decided to go with binary use/free
of 4K block. For quota size less than 4K size, report the
total=used=4K,free=0 when quota is full and total=free=4K,used=0
otherwise.
Signed-off-by: Kotresh HR <khiremat@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Add read-only module parameters for supported mount syntaxes. Primary
user is the user-space mount helper for catching v2 syntax bugs during
testing by cross verifying if the kernel supports v2 syntax on mount
failure.
Signed-off-by: Venky Shankar <vshankar@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Signed-off-by: Venky Shankar <vshankar@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Note that the new monitors are just shown in /proc/mounts.
Ceph does not (re)connect to new monitors yet.

[ jlayton: s/printk\(KERN_NOTICE/pr_notice(/
	   s/strcmp/strcmp_null/ ]
Signed-off-by: Venky Shankar <vshankar@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Old mount device syntax (source) has the following problems:

- mounts to the same cluster but with different fsnames
  and/or creds have identical device string which can
  confuse xfstests.

- Userspace mount helper tool resolves monitor addresses
  and fill in mon addrs automatically, but that means the
  device shown in /proc/mounts is different than what was
  used for mounting.

New device syntax is as follows:

  cephuser@fsid.mycephfs2=/path

Note, there is no "monitor address" in the device string.
That gets passed in as mount option. This keeps the device
string same when monitor addresses change (on remounts).

Also note that the userspace mount helper tool is backward
compatible. I.e., the mount helper will fallback to using
old syntax after trying to mount with the new syntax.

[ idryomov: drop CEPH_MON_ADDR_MNTOPT_DELIM ]
Signed-off-by: Venky Shankar <vshankar@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

... as it is too generic. also, use __func__ when logging
rather than hardcoding the function name.
Signed-off-by: Venky Shankar <vshankar@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

... and remove hardcoded function name in ceph_parse_ips().

[ idryomov: delim parameter, drop CEPH_ADDR_PARSE_DEFAULT_DELIM ]
Signed-off-by: Venky Shankar <vshankar@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Pull input fix from Dmitry Torokhov:
 "A small fixup to the Zinitix touchscreen driver to avoid enabling the
  IRQ line before we successfully requested it"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: zinitix - make sure the IRQ is allocated before it gets enabled

Pull ARM SoC fix from Olof Johansson:
 "One more fix for 5.16

  I had missed one patch when I sent up what I thought was the last
  batch of fixes for this release. This one fixes issues on the
  Raspberry Pi platforms due to gpio init changes this release, so
  hopefully we can get it merged before final release is cut"

* tag 'soc-fixes-5.16-5' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  ARM: dts: gpio-ranges property is now required

Merge tag 'perf-tools-fixes-for-v5.16-2022-01-09' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Revert "libtraceevent: Increase libtraceevent logging when verbose",
   breaks the build with libtraceevent-1.3.0, i.e. when building with
   'LIBTRACEEVENT_DYNAMIC=1'.

 - Avoid early exit in 'perf trace' due to running SIGCHLD handler
   before it makes sense to. It can happen when using a BPF source code
   event that have to be first built into an object file.

* tag 'perf-tools-fixes-for-v5.16-2022-01-09' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  Revert "libtraceevent: Increase libtraceevent logging when verbose"
  perf trace: Avoid early exit due to running SIGCHLD handler before it makes sense to

This reverts commit f7d6779d.

This bisected regression has impacted suspend-resume stability
since 5.15-rc1. It regressed -stable via 5.14.10.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215315
Fixes: f7d6779d ("drm/amdgpu: stop scheduler when calling hw_fini (v2)")
Cc: Guchun Chen <guchun.chen@amd.com>
Cc: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: <stable@vger.kernel.org> # 5.14+
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Since irq request is the last thing in the driver probe, it happens
later than the input device registration. This means that there is a
small time window where if the open method is called the driver will
attempt to enable not yet available irq.

Fix that by moving the irq request before the input device registration.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Fixes: 26822652 ("Input: add zinitix touchscreen driver")
Signed-off-by: Nikita Travkin <nikita@trvn.ru>
Link: https://lore.kernel.org/r/20220106072840.36851-2-nikita@trvn.ruSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Since [1], added in 5.7, the absence of a gpio-ranges property has
prevented GPIOs from being restored to inputs when released.
Add those properties for BCM283x and BCM2711 devices.

[1] commit 2ab73c6d ("gpio: Support GPIO controllers without
    pin-ranges")

Link: https://lore.kernel.org/r/20220104170247.956760-1-linus.walleij@linaro.org
Fixes: 2ab73c6d ("gpio: Support GPIO controllers without pin-ranges")
Fixes: 266423e6 ("pinctrl: bcm2835: Change init order for gpio hogs")
Reported-by: Stefan Wahren <stefan.wahren@i2se.com>
Reported-by: Florian Fainelli <f.fainelli@gmail.com>
Reported-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20211206092237.4105895-3-phil@raspberrypi.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

Pull ARM SoC fixes from Olof Johansson:
 "A few more fixes have come in, nothing overly severe but would be good
  to get in by final release:

   - More specific compatible fields on the qspi controller for socfpga,
     to enable quirks in the driver

   - A runtime PM fix for Renesas to fix mismatched reference counts on
     errors"

* tag 'soc-fixes-5.16-4' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  ARM: dts: socfpga: change qspi to "intel,socfpga-qspi"
  dt-bindings: spi: cadence-quadspi: document "intel,socfpga-qspi"
  reset: renesas: Fix Runtime PM usage

Pull i2c fixes from Wolfram Sang:
 "Fix the regression with AMD GPU suspend by reverting the
  handling of bus regulators in the I2C core.

  Also, there is a fix for the MPC driver to prevent an
  out-of-bound-access"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  Revert "i2c: core: support bus regulator controlling in adapter"
  i2c: mpc: Avoid out of bounds memory access

Pull power supply fixes from Sebastian Reichel:
 "Three fixes for the 5.16 cycle:

   - Avoid going beyond last capacity in the power-supply core

   - Replace 1E6L with NSEC_PER_MSEC to avoid floating point calculation
     in LLVM resulting in a build failure

   - Fix ADC measurements in bq25890 charger driver"

* tag 'for-v5.16-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply:
  power: reset: ltc2952: Fix use of floating point literals
  power: bq25890: Enable continuous conversion for ADC at charging
  power: supply: core: Break capacity loop

Pull xfs fix from Darrick Wong:

 - Make the old ALLOCSP ioctl behave in a consistent manner with newer
   syscalls like fallocate.

* tag 'xfs-5.16-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: map unwritten blocks in XFS_IOC_{ALLOC,FREE}SP just like fallocate

Pull cgroup fixes from Tejun Heo:
 "This contains the cgroup.procs permission check fixes so that they use
  the credentials at the time of open rather than write, which also
  fixes the cgroup namespace lifetime bug"

* 'for-5.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  selftests: cgroup: Test open-time cgroup namespace usage for migration checks
  selftests: cgroup: Test open-time credential usage for migration checks
  selftests: cgroup: Make cg_create() use 0755 for permission instead of 0644
  cgroup: Use open-time cgroup namespace for process migration perm checks
  cgroup: Allocate cgroup_file_ctx for kernfs_open_file->priv
  cgroup: Use open-time credentials for process migraton perm checks

Pull block fix from Jens Axboe:
 "Just the md bitmap regression this time"

* tag 'block-5.16-2022-01-07' of git://git.kernel.dk/linux-block:
  md/raid1: fix missing bitmap update w/o WriteMostly devices

Pull EDAC fix from Tony Luck:
 "Fix 10nm EDAC driver to release and unmap resources on systems without
  HBM"

* tag 'edac_urgent_for_v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
  EDAC/i10nm: Release mdev/mbase when failing to detect HBM

This largely reverts commit 5a7b95fb. It
breaks suspend with AMD GPUs, and we couldn't incrementally fix it. So,
let's remove the code and go back to the drawing board. We keep the
header extension to not break drivers already populating the regulator.
We expect to re-add the code handling it soon.

Fixes: 5a7b95fb ("i2c: core: support bus regulator controlling in adapter")
Reported-by: "Tareque Md.Hanif" <tarequemd.hanif@yahoo.com>
Link: https://lore.kernel.org/r/1295184560.182511.1639075777725@mail.yahoo.comReported-by: Konstantin Kharlamov <hi-angel@yandex.ru>
Link: https://lore.kernel.org/r/7143a7147978f4104171072d9f5225d2ce355ec1.camel@yandex.ru
BugLink: https://gitlab.freedesktop.org/drm/amd/-/issues/1850Tested-by: "Tareque Md.Hanif" <tarequemd.hanif@yahoo.com>
Tested-by: Konstantin Kharlamov <hi-angel@yandex.ru>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Cc: <stable@vger.kernel.org> # 5.14+

This reverts commit 08efcb4a.

This breaks the build as it will prefer using libbpf-devel header files,
even when not using LIBBPF_DYNAMIC=1, breaking the build.

This was detected on OpenSuSE Tumbleweed with libtraceevent-devel 1.3.0,
as described by Jiri Slaby:

=======================================================================
It breaks build with LIBTRACEEVENT_DYNAMIC and version 1.3.0:
> util/debug.c: In function ‘perf_debug_option’:
> util/debug.c:243:17: error: implicit declaration of function
‘tep_set_loglevel’ [-Werror=implicit-function-declaration]
>   243 |                 tep_set_loglevel(TEP_LOG_INFO);
>       |                 ^~~~~~~~~~~~~~~~
> util/debug.c:243:34: error: ‘TEP_LOG_INFO’ undeclared (first use in this
function); did you mean ‘TEP_PRINT_INFO’?
>   243 |                 tep_set_loglevel(TEP_LOG_INFO);
>       |                                  ^~~~~~~~~~~~
>       |                                  TEP_PRINT_INFO
> util/debug.c:243:34: note: each undeclared identifier is reported only once
for each function it appears in
> util/debug.c:245:34: error: ‘TEP_LOG_DEBUG’ undeclared (first use in this
function)
>   245 |                 tep_set_loglevel(TEP_LOG_DEBUG);
>       |                                  ^~~~~~~~~~~~~
> util/debug.c:247:34: error: ‘TEP_LOG_ALL’ undeclared (first use in this
function)
>   247 |                 tep_set_loglevel(TEP_LOG_ALL);
>       |                                  ^~~~~~~~~~~

It is because the gcc's command line looks like:
gcc
...
-I/home/abuild/rpmbuild/BUILD/tools/lib/
...
-DLIBTRACEEVENT_VERSION=65790
...
=======================================================================

The proper way to fix this is more involved and so not suitable for this
late in the 5.16-rc stage.
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/lkml/bc2b0786-8965-1bcd-2316-9d9bb37b9c31@kernel.org
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: https://lore.kernel.org/lkml/YddGjjmlMZzxUZbN@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When running 'perf trace' with an BPF object like:

  # perf trace -e openat,tools/perf/examples/bpf/hello.c

the event parsing eventually calls llvm__get_kbuild_opts() that runs a
script and that ends up with SIGCHLD delivered to the 'perf trace'
handler, which assumes the workload process is done and quits 'perf
trace'.

Move the SIGCHLD handler setup directly to trace__run(), where the event
is parsed and the object is already compiled.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Christy Lee <christyc.y.lee@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20220106222030.227499-1-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull kvm fixes from Paolo Bonzini:
 "Two small fixes for x86:

   - lockdep WARN due to missing lock nesting annotation

   - NULL pointer dereference when accessing debugfs"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: Check for rmaps allocation
  KVM: SEV: Mark nested locking of kvm->lock

Pull drm fixes from Dave Airlie:
 "There is only the amdgpu runtime pm regression fix in here:

  amdgpu:

   - suspend/resume fix

   - fix runtime PM regression"

* tag 'drm-fixes-2022-01-07' of git://anongit.freedesktop.org/drm/drm:
  drm/amdgpu: disable runpm if we are the primary adapter
  fbdev: fbmem: add a helper to determine if an aperture is used by a fw fb
  drm/amd/pm: keep the BACO feature enabled for suspend

With TDP MMU being the default now, access to mmu_rmaps_stat debugfs
file causes following oops:

BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 7 PID: 3185 Comm: cat Not tainted 5.16.0-rc4+ #204
RIP: 0010:pte_list_count+0x6/0x40
 Call Trace:
  <TASK>
  ? kvm_mmu_rmaps_stat_show+0x15e/0x320
  seq_read_iter+0x126/0x4b0
  ? aa_file_perm+0x124/0x490
  seq_read+0xf5/0x140
  full_proxy_read+0x5c/0x80
  vfs_read+0x9f/0x1a0
  ksys_read+0x67/0xe0
  __x64_sys_read+0x19/0x20
  do_syscall_64+0x3b/0xc0
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7fca6fc13912

Return early when rmaps are not present.
Reported-by: Vasant Hegde <vasant.hegde@amd.com>
Tested-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Nikunj A Dadhania <nikunj@amd.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220105040337.4234-1-nikunj@amd.com>
Cc: stable@vger.kernel.org
Fixes: 3bcd0662 ("KVM: X86: Introduce mmu_rmaps_stat per-vm debugfs file")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Both source and dest vms' kvm->locks are held in sev_lock_two_vms.
Mark one with a different subtype to avoid false positives from lockdep.

Fixes: c9d61dcb (KVM: SEV: accept signals in sev_lock_two_vms)
Reported-by: Yiru Xu <xyru1999@gmail.com>
Tested-by: Jinrong Liang <cloudliang@tencent.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1641364863-26331-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Pull rdma fixes from Jason Gunthorpe:
 "Last pull for 5.16, the reversion has been known for a while now but
  didn't get a proper fix in time. Looks like we will have several
  info-leak bugs to take care of going foward.

   - Revert the patch fixing the DM related crash causing a widespread
     regression for kernel ULPs. A proper fix just didn't appear this
     cycle due to the holidays

   - Missing NULL check on alloc in uverbs

   - Double free in rxe error paths

   - Fix a new kernel-infoleak report when forming ah_attr's without
     GRH's in ucma"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  RDMA/core: Don't infoleak GRH fields
  RDMA/uverbs: Check for null return of kmalloc_array
  Revert "RDMA/mlx5: Fix releasing unallocated memory in dereg MR flow"
  RDMA/rxe: Prevent double freeing rxe_map_set()

Pull tracing fixes from Steven Rostedt:
 "Three minor tracing fixes:

   - Fix missing prototypes in sample module for direct functions

   - Fix check of valid buffer in get_trace_buf()

   - Fix annotations of percpu pointers"

* tag 'trace-v5.16-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Tag trace_percpu_buffer as a percpu pointer
  tracing: Fix check for trace_percpu_buffer validity in get_trace_buf()
  ftrace/samples: Add missing prototypes direct functions

When a task is writing to an fd opened by a different task, the perm check
should use the cgroup namespace of the latter task. Add a test for it.
Tested-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

When a task is writing to an fd opened by a different task, the perm check
should use the credentials of the latter task. Add a test for it.
Tested-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

0644 is an odd perm to create a cgroup which is a directory. Use the regular
0755 instead. This is necessary for euid switching test case.
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

cgroup process migration permission checks are performed at write time as
whether a given operation is allowed or not is dependent on the content of
the write - the PID. This currently uses current's cgroup namespace which is
a potential security weakness as it may allow scenarios where a less
privileged process tricks a more privileged one into writing into a fd that
it created.

This patch makes cgroup remember the cgroup namespace at the time of open
and uses it for migration permission checks instad of current's. Note that
this only applies to cgroup2 as cgroup1 doesn't have namespace support.

This also fixes a use-after-free bug on cgroupns reported in

 https://lore.kernel.org/r/00000000000048c15c05d0083397@google.com

Note that backporting this fix also requires the preceding patch.
Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Reported-by: syzbot+50f5cf33a284ce738b62@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/00000000000048c15c05d0083397@google.com
Fixes: 5136f636 ("cgroup: implement "nsdelegate" mount option")
Signed-off-by: Tejun Heo <tj@kernel.org>

of->priv is currently used by each interface file implementation to store
private information. This patch collects the current two private data usages
into struct cgroup_file_ctx which is allocated and freed by the common path.
This allows generic private data which applies to multiple files, which will
be used to in the following patch.

Note that cgroup_procs iterator is now embedded as procs.iter in the new
cgroup_file_ctx so that it doesn't need to be allocated and freed
separately.

v2: union dropped from cgroup_file_ctx and the procs iterator is embedded in
    cgroup_file_ctx as suggested by Linus.

v3: Michal pointed out that cgroup1's procs pidlist uses of->priv too.
    Converted. Didn't change to embedded allocation as cgroup1 pidlists get
    stored for caching.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Michal Koutný <mkoutny@suse.com>