<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include, branch v5.15.53</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.15.53</id>
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<updated>2022-07-07T15:53:34Z</updated>
<entry>
<title>drm/fourcc: fix integer type usage in uapi header</title>
<updated>2022-07-07T15:53:34Z</updated>
<author>
<name>Carlos Llamas</name>
<email>cmllamas@google.com</email>
</author>
<published>2022-06-21T20:39:21Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=5b458d3de9cfac4a21b704c90c8c7eff244c8b13'/>
<id>urn:sha1:5b458d3de9cfac4a21b704c90c8c7eff244c8b13</id>
<content type='text'>
[ Upstream commit 20b8264394b33adb1640a485a62a84bc1388b6a3 ]

Kernel uapi headers are supposed to use __[us]{8,16,32,64} types defined
by &lt;linux/types.h&gt; as opposed to 'uint32_t' and similar. See [1] for the
relevant discussion about this topic. In this particular case, the usage
of 'uint64_t' escaped headers_check as these macros are not being called
here. However, the following program triggers a compilation error:

  #include &lt;drm/drm_fourcc.h&gt;

  int main()
  {
  	unsigned long x = AMD_FMT_MOD_CLEAR(RB);
  	return 0;
  }

gcc error:
  drm.c:5:27: error: ‘uint64_t’ undeclared (first use in this function)
      5 |         unsigned long x = AMD_FMT_MOD_CLEAR(RB);
        |                           ^~~~~~~~~~~~~~~~~

This patch changes AMD_FMT_MOD_{SET,CLEAR} macros to use the correct
integer types, which fixes the above issue.

  [1] https://lkml.org/lkml/2019/6/5/18

Fixes: 8ba16d599374 ("drm/fourcc: Add AMD DRM modifiers.")
Signed-off-by: Carlos Llamas &lt;cmllamas@google.com&gt;
Reviewed-by: Simon Ser &lt;contact@emersion.fr&gt;
Signed-off-by: Alex Deucher &lt;alexander.deucher@amd.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: fix IFF_TX_SKB_NO_LINEAR definition</title>
<updated>2022-07-07T15:53:32Z</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2022-06-23T13:32:32Z</published>
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<id>urn:sha1:4dc036ddf4bf224088036b856d6ff555fdca180e</id>
<content type='text'>
[ Upstream commit 3b89b511ea0c705cc418440e2abf9d692a556d84 ]

The "1&lt;&lt;31" shift has a sign extension bug so IFF_TX_SKB_NO_LINEAR is
0xffffffff80000000 instead of 0x0000000080000000.

Fixes: c2ff53d8049f ("net: Add priv_flags for allow tx skb without linear")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Reviewed-by: Xuan Zhuo &lt;xuanzhuo@linux.alibaba.com&gt;
Link: https://lore.kernel.org/r/YrRrcGttfEVnf85Q@kili
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>linux/dim: Fix divide by 0 in RDMA DIM</title>
<updated>2022-07-07T15:53:26Z</updated>
<author>
<name>Tao Liu</name>
<email>thomas.liu@ucloud.cn</email>
</author>
<published>2022-06-27T14:00:04Z</published>
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<id>urn:sha1:0b6e0eb5c45e79e9095de2498cc0ca5ec563fc5e</id>
<content type='text'>
commit 0fe3dbbefb74a8575f61d7801b08dbc50523d60d upstream.

Fix a divide 0 error in rdma_dim_stats_compare() when prev-&gt;cpe_ratio ==
0.

CallTrace:
  Hardware name: H3C R4900 G3/RS33M2C9S, BIOS 2.00.37P21 03/12/2020
  task: ffff880194b78000 task.stack: ffffc90006714000
  RIP: 0010:backport_rdma_dim+0x10e/0x240 [mlx_compat]
  RSP: 0018:ffff880c10e83ec0 EFLAGS: 00010202
  RAX: 0000000000002710 RBX: ffff88096cd7f780 RCX: 0000000000000064
  RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001
  RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000000 R12: 000000001d7c6c09
  R13: ffff88096cd7f780 R14: ffff880b174fe800 R15: 0000000000000000
  FS:  0000000000000000(0000) GS:ffff880c10e80000(0000)
  knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00000000a0965b00 CR3: 000000000200a003 CR4: 00000000007606e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:
   &lt;IRQ&gt;
   ib_poll_handler+0x43/0x80 [ib_core]
   irq_poll_softirq+0xae/0x110
   __do_softirq+0xd1/0x28c
   irq_exit+0xde/0xf0
   do_IRQ+0x54/0xe0
   common_interrupt+0x8f/0x8f
   &lt;/IRQ&gt;
   ? cpuidle_enter_state+0xd9/0x2a0
   ? cpuidle_enter_state+0xc7/0x2a0
   ? do_idle+0x170/0x1d0
   ? cpu_startup_entry+0x6f/0x80
   ? start_secondary+0x1b9/0x210
   ? secondary_startup_64+0xa5/0xb0
  Code: 0f 87 e1 00 00 00 8b 4c 24 14 44 8b 43 14 89 c8 4d 63 c8 44 29 c0 99 31 d0 29 d0 31 d2 48 98 48 8d 04 80 48 8d 04 80 48 c1 e0 02 &lt;49&gt; f7 f1 48 83 f8 0a 0f 86 c1 00 00 00 44 39 c1 7f 10 48 89 df
  RIP: backport_rdma_dim+0x10e/0x240 [mlx_compat] RSP: ffff880c10e83ec0

Fixes: f4915455dcf0 ("linux/dim: Implement RDMA adaptive moderation (DIM)")
Link: https://lore.kernel.org/r/20220627140004.3099-1-thomas.liu@ucloud.cn
Signed-off-by: Tao Liu &lt;thomas.liu@ucloud.cn&gt;
Reviewed-by: Max Gurtovoy &lt;mgurtovoy@nvidia.com&gt;
Acked-by: Leon Romanovsky &lt;leonro@nvidia.com&gt;
Signed-off-by: Jason Gunthorpe &lt;jgg@nvidia.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: phy: Don't trigger state machine while in suspend</title>
<updated>2022-07-07T15:53:24Z</updated>
<author>
<name>Lukas Wunner</name>
<email>lukas@wunner.de</email>
</author>
<published>2022-06-28T10:15:08Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=25fab798784b0312d408b827475bd5a77ff94753'/>
<id>urn:sha1:25fab798784b0312d408b827475bd5a77ff94753</id>
<content type='text'>
commit 1758bde2e4aa5ff188d53e7d9d388bbb7e12eebb upstream.

Upon system sleep, mdio_bus_phy_suspend() stops the phy_state_machine(),
but subsequent interrupts may retrigger it:

They may have been left enabled to facilitate wakeup and are not
quiesced until the -&gt;suspend_noirq() phase.  Unwanted interrupts may
hence occur between mdio_bus_phy_suspend() and dpm_suspend_noirq(),
as well as between dpm_resume_noirq() and mdio_bus_phy_resume().

Retriggering the phy_state_machine() through an interrupt is not only
undesirable for the reason given in mdio_bus_phy_suspend() (freezing it
midway with phydev-&gt;lock held), but also because the PHY may be
inaccessible after it's suspended:  Accesses to USB-attached PHYs are
blocked once usb_suspend_both() clears the can_submit flag and PHYs on
PCI network cards may become inaccessible upon suspend as well.

Amend phy_interrupt() to avoid triggering the state machine if the PHY
is suspended.  Signal wakeup instead if the attached net_device or its
parent has been configured as a wakeup source.  (Those conditions are
identical to mdio_bus_phy_may_suspend().)  Postpone handling of the
interrupt until the PHY has resumed.

Before stopping the phy_state_machine() in mdio_bus_phy_suspend(),
wait for a concurrent phy_interrupt() to run to completion.  That is
necessary because phy_interrupt() may have checked the PHY's suspend
status before the system sleep transition commenced and it may thus
retrigger the state machine after it was stopped.

Likewise, after re-enabling interrupt handling in mdio_bus_phy_resume(),
wait for a concurrent phy_interrupt() to complete to ensure that
interrupts which it postponed are properly rerun.

The issue was exposed by commit 1ce8b37241ed ("usbnet: smsc95xx: Forward
PHY interrupts to PHY driver to avoid polling"), but has existed since
forever.

Fixes: 541cd3ee00a4 ("phylib: Fix deadlock on resume")
Link: https://lore.kernel.org/netdev/a5315a8a-32c2-962f-f696-de9a26d30091@samsung.com/
Reported-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Tested-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Acked-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Cc: stable@vger.kernel.org # v2.6.33+
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Link: https://lore.kernel.org/r/b7f386d04e9b5b0e2738f0125743e30676f309ef.1656410895.git.lukas@wunner.de
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>fs: fix acl translation</title>
<updated>2022-07-02T14:41:17Z</updated>
<author>
<name>Christian Brauner</name>
<email>brauner@kernel.org</email>
</author>
<published>2022-06-28T12:16:19Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=dc85bc24fbf13d2ef36d41da970776c4f94b68dd'/>
<id>urn:sha1:dc85bc24fbf13d2ef36d41da970776c4f94b68dd</id>
<content type='text'>
commit 705191b03d507744c7e097f78d583621c14988ac upstream.

Last cycle we extended the idmapped mounts infrastructure to support
idmapped mounts of idmapped filesystems (No such filesystem yet exist.).
Since then, the meaning of an idmapped mount is a mount whose idmapping
is different from the filesystems idmapping.

While doing that work we missed to adapt the acl translation helpers.
They still assume that checking for the identity mapping is enough.  But
they need to use the no_idmapping() helper instead.

Note, POSIX ACLs are always translated right at the userspace-kernel
boundary using the caller's current idmapping and the initial idmapping.
The order depends on whether we're coming from or going to userspace.
The filesystem's idmapping doesn't matter at the border.

Consequently, if a non-idmapped mount is passed we need to make sure to
always pass the initial idmapping as the mount's idmapping and not the
filesystem idmapping.  Since it's irrelevant here it would yield invalid
ids and prevent setting acls for filesystems that are mountable in a
userns and support posix acls (tmpfs and fuse).

I verified the regression reported in [1] and verified that this patch
fixes it.  A regression test will be added to xfstests in parallel.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215849 [1]
Fixes: bd303368b776 ("fs: support mapped mounts of mapped filesystems")
Cc: Seth Forshee &lt;sforshee@digitalocean.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: &lt;stable@vger.kernel.org&gt; # 5.15+
Cc: &lt;regressions@lists.linux.dev&gt;
Signed-off-by: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>fs: support mapped mounts of mapped filesystems</title>
<updated>2022-07-02T14:41:17Z</updated>
<author>
<name>Christian Brauner</name>
<email>christian.brauner@ubuntu.com</email>
</author>
<published>2022-06-28T12:16:18Z</published>
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<id>urn:sha1:38753e9173a5903e902c856b41fb325762bf5945</id>
<content type='text'>
commit bd303368b776eead1c29e6cdda82bde7128b82a7 upstream.

In previous patches we added new and modified existing helpers to handle
idmapped mounts of filesystems mounted with an idmapping. In this final
patch we convert all relevant places in the vfs to actually pass the
filesystem's idmapping into these helpers.

With this the vfs is in shape to handle idmapped mounts of filesystems
mounted with an idmapping. Note that this is just the generic
infrastructure. Actually adding support for idmapped mounts to a
filesystem mountable with an idmapping is follow-up work.

In this patch we extend the definition of an idmapped mount from a mount
that that has the initial idmapping attached to it to a mount that has
an idmapping attached to it which is not the same as the idmapping the
filesystem was mounted with.

As before we do not allow the initial idmapping to be attached to a
mount. In addition this patch prevents that the idmapping the filesystem
was mounted with can be attached to a mount created based on this
filesystem.

This has multiple reasons and advantages. First, attaching the initial
idmapping or the filesystem's idmapping doesn't make much sense as in
both cases the values of the i_{g,u}id and other places where k{g,u}ids
are used do not change. Second, a user that really wants to do this for
whatever reason can just create a separate dedicated identical idmapping
to attach to the mount. Third, we can continue to use the initial
idmapping as an indicator that a mount is not idmapped allowing us to
continue to keep passing the initial idmapping into the mapping helpers
to tell them that something isn't an idmapped mount even if the
filesystem is mounted with an idmapping.

Link: https://lore.kernel.org/r/20211123114227.3124056-11-brauner@kernel.org (v1)
Link: https://lore.kernel.org/r/20211130121032.3753852-11-brauner@kernel.org (v2)
Link: https://lore.kernel.org/r/20211203111707.3901969-11-brauner@kernel.org
Cc: Seth Forshee &lt;sforshee@digitalocean.com&gt;
Cc: Amir Goldstein &lt;amir73il@gmail.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
CC: linux-fsdevel@vger.kernel.org
Reviewed-by: Seth Forshee &lt;sforshee@digitalocean.com&gt;
Signed-off-by: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Signed-off-by: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>fs: add i_user_ns() helper</title>
<updated>2022-07-02T14:41:16Z</updated>
<author>
<name>Christian Brauner</name>
<email>christian.brauner@ubuntu.com</email>
</author>
<published>2022-06-28T12:16:17Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=968e66f8ff70285744ac506cd5668223d5eebe41'/>
<id>urn:sha1:968e66f8ff70285744ac506cd5668223d5eebe41</id>
<content type='text'>
commit a1ec9040a2a9122605ac26e5725c6de019184419 upstream.

Since we'll be passing the filesystem's idmapping in even more places in
the following patches and we do already dereference struct inode to get
to the filesystem's idmapping multiple times add a tiny helper.

Link: https://lore.kernel.org/r/20211123114227.3124056-10-brauner@kernel.org (v1)
Link: https://lore.kernel.org/r/20211130121032.3753852-10-brauner@kernel.org (v2)
Link: https://lore.kernel.org/r/20211203111707.3901969-10-brauner@kernel.org
Cc: Seth Forshee &lt;sforshee@digitalocean.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
CC: linux-fsdevel@vger.kernel.org
Reviewed-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Reviewed-by: Seth Forshee &lt;sforshee@digitalocean.com&gt;
Signed-off-by: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Signed-off-by: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>fs: port higher-level mapping helpers</title>
<updated>2022-07-02T14:41:16Z</updated>
<author>
<name>Christian Brauner</name>
<email>christian.brauner@ubuntu.com</email>
</author>
<published>2022-06-28T12:16:16Z</published>
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<id>urn:sha1:21c6c720be75049913336099c33129089497d7cb</id>
<content type='text'>
commit 209188ce75d0d357c292f6bb81d712acdd4e7db7 upstream.

Enable the mapped_fs{g,u}id() helpers to support filesystems mounted
with an idmapping. Apart from core mapping helpers that use
mapped_fs{g,u}id() to initialize struct inode's i_{g,u}id fields xfs is
the only place that uses these low-level helpers directly.

The patch only extends the helpers to be able to take the filesystem
idmapping into account. Since we don't actually yet pass the
filesystem's idmapping in no functional changes happen. This will happen
in a final patch.

Link: https://lore.kernel.org/r/20211123114227.3124056-9-brauner@kernel.org (v1)
Link: https://lore.kernel.org/r/20211130121032.3753852-9-brauner@kernel.org (v2)
Link: https://lore.kernel.org/r/20211203111707.3901969-9-brauner@kernel.org
Cc: Seth Forshee &lt;sforshee@digitalocean.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
CC: linux-fsdevel@vger.kernel.org
Reviewed-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Reviewed-by: Seth Forshee &lt;sforshee@digitalocean.com&gt;
Signed-off-by: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Signed-off-by: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>fs: remove unused low-level mapping helpers</title>
<updated>2022-07-02T14:41:16Z</updated>
<author>
<name>Christian Brauner</name>
<email>christian.brauner@ubuntu.com</email>
</author>
<published>2022-06-28T12:16:15Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=7d0536a8fab719544db98e58ad49b9a07332922d'/>
<id>urn:sha1:7d0536a8fab719544db98e58ad49b9a07332922d</id>
<content type='text'>
commit 02e4079913500f24ceb082d8d87d8665f044b298 upstream.

Now that we ported all places to use the new low-level mapping helpers
that are able to support filesystems mounted with an idmapping we can
remove the old low-level mapping helpers. With the removal of these old
helpers we also conclude the renaming of the mapping helpers we started
in commit a65e58e791a1 ("fs: document and rename fsid helpers").

Link: https://lore.kernel.org/r/20211123114227.3124056-8-brauner@kernel.org (v1)
Link: https://lore.kernel.org/r/20211130121032.3753852-8-brauner@kernel.org (v2)
Link: https://lore.kernel.org/r/20211203111707.3901969-8-brauner@kernel.org
Cc: Seth Forshee &lt;sforshee@digitalocean.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
CC: linux-fsdevel@vger.kernel.org
Reviewed-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Reviewed-by: Seth Forshee &lt;sforshee@digitalocean.com&gt;
Signed-off-by: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Signed-off-by: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>fs: account for filesystem mappings</title>
<updated>2022-07-02T14:41:15Z</updated>
<author>
<name>Christian Brauner</name>
<email>christian.brauner@ubuntu.com</email>
</author>
<published>2022-06-28T12:16:12Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b20dcf603b8d0bb24a45c8e6cdd345e3fb3aa3d4'/>
<id>urn:sha1:b20dcf603b8d0bb24a45c8e6cdd345e3fb3aa3d4</id>
<content type='text'>
commit 1ac2a4104968e0a60b4b3572216a92aab5c1b025 upstream.

Currently we only support idmapped mounts for filesystems mounted
without an idmapping. This was a conscious decision mentioned in
multiple places (cf. e.g. [1]).

As explained at length in [3] it is perfectly fine to extend support for
idmapped mounts to filesystem's mounted with an idmapping should the
need arise. The need has been there for some time now. Various container
projects in userspace need this to run unprivileged and nested
unprivileged containers (cf. [2]).

Before we can port any filesystem that is mountable with an idmapping to
support idmapped mounts we need to first extend the mapping helpers to
account for the filesystem's idmapping. This again, is explained at
length in our documentation at [3] but I'll give an overview here again.

Currently, the low-level mapping helpers implement the remapping
algorithms described in [3] in a simplified manner. Because we could
rely on the fact that all filesystems supporting idmapped mounts are
mounted without an idmapping the translation step from or into the
filesystem idmapping could be skipped.

In order to support idmapped mounts of filesystem's mountable with an
idmapping the translation step we were able to skip before cannot be
skipped anymore. A filesystem mounted with an idmapping is very likely
to not use an identity mapping and will instead use a non-identity
mapping. So the translation step from or into the filesystem's idmapping
in the remapping algorithm cannot be skipped for such filesystems. More
details with examples can be found in [3].

This patch adds a few new and prepares some already existing low-level
mapping helpers to perform the full translation algorithm explained in
[3]. The low-level helpers can be written in a way that they only
perform the additional translation step when the filesystem is indeed
mounted with an idmapping.

If the low-level helpers detect that they are not dealing with an
idmapped mount they can simply return the relevant k{g,u}id unchanged;
no remapping needs to be performed at all. The no_idmapping() helper
detects whether the shortcut can be used.

If the low-level helpers detected that they are dealing with an idmapped
mount but the underlying filesystem is mounted without an idmapping we
can rely on the previous shorcut and can continue to skip the
translation step from or into the filesystem's idmapping.

These checks guarantee that only the minimal amount of work is
performed. As before, if idmapped mounts aren't used the low-level
helpers are idempotent and no work is performed at all.

This patch adds the helpers mapped_k{g,u}id_fs() and
mapped_k{g,u}id_user(). Following patches will port all places to
replace the old k{g,u}id_into_mnt() and k{g,u}id_from_mnt() with these
two new helpers. After the conversion is done k{g,u}id_into_mnt() and
k{g,u}id_from_mnt() will be removed. This also concludes the renaming of
the mapping helpers we started in [4]. Now, all mapping helpers will
started with the "mapped_" prefix making everything nice and consistent.

The mapped_k{g,u}id_fs() helpers replace the k{g,u}id_into_mnt()
helpers. They are to be used when k{g,u}ids are to be mapped from the
vfs, e.g. from from struct inode's i_{g,u}id.  Conversely, the
mapped_k{g,u}id_user() helpers replace the k{g,u}id_from_mnt() helpers.
They are to be used when k{g,u}ids are to be written to disk, e.g. when
entering from a system call to change ownership of a file.

This patch only introduces the helpers. It doesn't yet convert the
relevant places to account for filesystem mounted with an idmapping.

[1]: commit 2ca4dcc4909d ("fs/mount_setattr: tighten permission checks")
[2]: https://github.com/containers/podman/issues/10374
[3]: Documentations/filesystems/idmappings.rst
[4]: commit a65e58e791a1 ("fs: document and rename fsid helpers")

Link: https://lore.kernel.org/r/20211123114227.3124056-5-brauner@kernel.org (v1)
Link: https://lore.kernel.org/r/20211130121032.3753852-5-brauner@kernel.org (v2)
Link: https://lore.kernel.org/r/20211203111707.3901969-5-brauner@kernel.org
Cc: Seth Forshee &lt;sforshee@digitalocean.com&gt;
Cc: Amir Goldstein &lt;amir73il@gmail.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
CC: linux-fsdevel@vger.kernel.org
Reviewed-by: Seth Forshee &lt;sforshee@digitalocean.com&gt;
Signed-off-by: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Signed-off-by: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
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