So userspace can query the kernel for command parser support.
v2: Add i915_cmd_parser_get_version(), history log, and kerneldoc
OTC-Tracker: AXIA-4631
Change-Id: I58af650db9f6753c2dcac9c54ab432fd31db302f
Signed-off-by: Brad Volkin <bradley.d.volkin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
PIPE_CONTROL and MI_FLUSH_DW have bits that would write to the
hardware status page. The driver stores request tracking info
there, so don't let userspace overwrite it.
v2: trailing comma fix, rebased
Signed-off-by: Brad Volkin <bradley.d.volkin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Various commands that access memory have a bit to determine whether
the graphics address specified in the command should use the GGTT or
PPGTT for translation. These checks ensure that the bit indicates
PPGTT translation.
Most of these checks use the existing bit-checking infrastructure.
The PIPE_CONTROL and MI_FLUSH_DW commands, however, are multi-function
commands. The GGTT/PPGTT bit is only relevant for certain uses of the
command. As such, this change also extends the bit-checking code to
include a "condition" mask and offset. If the condition mask is non-zero
then the parser only performs the bit check when the bits specified by
the condition mask/offset are also non-zero.
NOTE: At this point in the series PPGTT must be enabled for the parser
to work correctly. If it's not enabled, userspace will not be setting
the PPGTT bits the way the parser requires. VLV is the only platform
where this is a problem, so at this point, we disable parsing for VLV.
v2: whitespace and trailing commas fixes, rebased
OTC-Tracker: AXIA-4631
Change-Id: I3f4c76b6734f1956ec47e698230f97d0998ff92b
Signed-off-by: Brad Volkin <bradley.d.volkin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
[danvet: Drop the unecessary cast Jani spotted.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The driver leaves most interrupts masked during normal operation,
so there would have to be additional work to enable userspace to
safely request/receive an interrupt.
v2: trailing commas, rebased
Signed-off-by: Brad Volkin <bradley.d.volkin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
MI_STORE_REGISTER_MEM, MI_LOAD_REGISTER_MEM, and MI_LOAD_REGISTER_IMM
commands allow userspace access to registers. Only certain registers
should be allowed for such access, so enable checking for those commands.
Each ring gets its own register whitelist.
MI_LOAD_REGISTER_REG on HSW also allows register access but is currently
unused by userspace components. Leave it rejected.
PIPE_CONTROL and MEDIA_VFE_STATE allow register access based on certain
bits being set. Reject those as well.
v2: trailing commas, rebased
OTC-Tracker: AXIA-4631
Change-Id: Ie614a2f0eb2e5917de809e5a17957175d24cc44f
Signed-off-by: Brad Volkin <bradley.d.volkin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
These are used to implement scanline waits in the X server.
v2: Use #defines instead of magic numbers
Signed-off-by: Brad Volkin <bradley.d.volkin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
These registers are currently used by mesa for blitting,
transform feedback extensions, and performance monitoring
extensions.
v2: REG64 macro
Signed-off-by: Brad Volkin <bradley.d.volkin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The Intel DDX uses these to implement scanline waits in the X server.
Signed-off-by: Brad Volkin <bradley.d.volkin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The spec defines most of these commands as privileged. A few others,
like the semaphore mbox command and some display commands, are also
reserved for the driver's use. Subsequent patches relax some of
these restrictions.
v2: Rebased
Signed-off-by: Brad Volkin <bradley.d.volkin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Add command tables defining irregular length commands for each ring.
This requires a few new command opcode definitions.
v2: Whitespace adjustment in command definitions, sparse fix for !F
OTC-Tracker: AXIA-4631
Change-Id: I064bceb457e15f46928058352afe76d918c58ef5
Signed-off-by: Brad Volkin <bradley.d.volkin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
When PPGTT was disabled by default, the patch also prevented the user
from overriding this behavior via module parameter. Being able to test
this on arbitrary kernels is extremely beneficial to track down the
remaining bugs. The patch that prevented this was:
commit 93a25a9e2d
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu Mar 6 09:40:43 2014 +0100
drm/i915: Disable full ppgtt by default
By default PPGTT is set to -1. 0 means off, 1 means aliasing only, 2
means full, all other values are reserved.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This file contains all necessary defines, prototypes and typesdefs for
manipulating GEN graphics address translation (this does not include the
legacy AGP driver)
Reiterating the comment in the header,
"Please try to maintain the following order within this file unless it
makes sense to do otherwise. From top to bottom:
1. typedefs
2. #defines, and macros
3. structure definitions
4. function prototypes
Within each section, please try to order by generation in ascending
order, from top to bottom (ie. GEN6 on the top, GEN8 on the bottom)."
I've made some minor cleanups, and fixed a couple of typos while here -
but there should be no functional changes.
The purpose of the patch is to reduce clutter in our main header file,
making room for new growth, and make documentation of our interfaces
easier by splitting things out.
With a little more work, like making i915_gtt a pointer, we could
potentially completely isolate this header from i915_drv.h. At the
moment however, I don't think it's worth the effort.
Personally, I would have liked to put the PTE encoding functions in this
file too, but I didn't want to rock the boat too much.
A similar patch has been in use on my machine for some time. This exact
patch though has only been compile tested.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Extract all this logic into a new helper function
semaphore_wait_to_signaller_ring because:
- The current code has way too much magic.
- The current code doesn't look at bi16, which encodes VECS signallers
on HSW. Those are just added after the fact, so can't be encoded in
a neat formula.
- The current logic can't blow up since it limits its value range
sufficiently, but that's a bit too tricky to rely on in my opinion.
Especially when we start to add bdw support.
- I'm not a big fan of the explicit ring->semaphore_register list, but
I think it's more robust to use the same mapping both when
constructing the semaphore commands and when decoding them.
- Finally add a FIXME comment about lack of broadwell support here,
like in the earlier ipehr semaphore cmd detection function.
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
[danvet: Actually drop the untrue claim in the commit message Chris
pointed out.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Currently not an issue since we don't emit sempahores, but better
not forget about those.
As a little prep work extract the ipehr decoding for cleaner control
flow. And apply a bit of polish.
Cc: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The documentation calls this GFX_MODE bit "Flush TLB invalidate Mode".
However, that is not a good name for an enable bit as it doesn't make it
clear what is enabled. An even worse name is GFX_TLB_INVALIDATE_ALWAYS
as enabling that bit actually prevents the TLB from being invalidated at
every flush. This leads to great confusion when reading code and
proposed patches. To get around this try to bake in what is enabled by
setting the bit and call it GFX_TLB_INVALIDATE_EXPLICIT.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: "Gupta, Sourab" <sourab.gupta@intel.com>
Acked-by: "Gupta, Sourab" <sourab.gupta@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Because gen6_gt_force_wake_{get,put} should already be responsible for
getting/putting runtime PM. If we keep these calls, debugfs will not
be testing the get/put calls of the forcewake functions.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
If runtime PM is enabled and we unset all modes, we will runtime
suspend after __intel_set_mode() , then function
intel_modeset_check_state() will try to read the HW state while it is
suspended and trigger lots of WARNs because it shouldn't be reading
registers.
So on this patch we make intel_ddi_connector_get_hw_state() return
false in case the power domain is disabled, and we also make
intel_display_power_enabled() return false in case the device is
suspended. Notice that we can't just use
intel_display_power_enabled_sw() because while the driver is being
initialized the power domain refcounts are not reflecting the real
state of the hardware.
Just for reference, I have previously published an alternate patch for
this problem, called "drm/i915: get runtime PM at intel_set_mode".
Testcase: igt/pm_pc8
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
At i915_display_info, don't call cursor_position() for a disabled
CRTC, since the CRTC may be on a powered down pipe, and this will
cause "Unclaimed register before interrupt" error messages.
Testcase: igt/pm_pc8/debugfs-read
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Otherwise we may get some WARNs complaining that we're reading a
register while we're suspended.
Testcase: igt/pm_pc8/debugfs-read
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
To avoid WARNs when we call it.
Testcase: igt/pm_pc8/reg-read-ioctl
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=75693
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
So far force_wake_timer was only used by gen6_gt_force_wake_put. Since
we always had balanced gen6_gt_force_wake_get/put calls, we could
guarantee balanced calls to intel_runtime_pm_get/put.
Commit 8232644ccf, "drm/i915: Convert
the forcewake worker into a timer func" started scheduling the
force_wake_timer at gen6_read, which resulted in an unbalanced
runtime_pm refcount.
So this commit just reverts to the old behavior until we can find a
proper way to used delayed force_wake from the register read/write
macros without leaving the runtime_pm refcounts unbalanced and without
runtime suspending the driver while forcewake is active.
Testcase: igt/pm_pc8/rte
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76544
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Atm we reserve/allocate and free the power context during GT power
enable/disable time. There is no need to do this, we can reserve/allocate
the buffer once during driver loading and free it during driver cleanup.
The re-reservation can also fail in case the driver previously manages to
allocate something on the given fixed address.
The buffer isn't exepected to move even if allocated by the BIOS, for
safety add an assert to check this assumption.
This also fixed a bug for Ville, where re-reserving the context failed
during a GPU reset (I assume because something else got allocated on its
fixed address).
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Remove the rest of the references to drm_i915_private_t. No functional
changes.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
[danvet: Drop hunk in i915_cmd_parser.c]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Also drop any unnecessary casts. No functional changes.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Also drop any unnecessary casts. No functional changes.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The speculation is that we can conserve more power by masking off
the interrupts at source (PMINTRMSK) rather than filtering them by the
up/down thresholds (RPINTLIM). We can select which events we know will
be active based on the current frequency versus our imposed range, i.e.
if at minimum, we know we will not want to generate any more
down-interrupts and vice versa.
v2: We only need the TIMEOUT when above min frequency.
v3: Tweak VLV at the same time
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Deepak S <deepak.s@linux.intel.com>
Reviewed-by:Deepak S <deepak.s@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
What used to be a short-circuit now needs to adjust interrupt masking in
response to user requests for changing the min/max allowed frequencies.
This is currently done by a special case and early return, but the next
patch adds another common action to take, so refactor the code to reduce
duplication.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by:Deepak S <deepak.s@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This reverts commit 2754436913.
Conflicts:
drivers/gpu/drm/i915/i915_irq.c
The partial application of interrupt masking without regard to other
pathways for adjusting the RPS frequency results in completely disabling
the PM interrupts. This leads to excessive power consumption as the GPU
is kept at max clocks (until the failsafe mechanism fires of explicitly
downclocking the GPU when all requests are idle). Or equally as bad for
the UX, the GPU is kept at minimum clocks and prevented from upclocking
in response to a requirement for more power.
Testcase: pm_rps/blocking
Cc: Deepak S <deepak.s@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by:Deepak S <deepak.s@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
If vsyncshift comes out as negative, add one htotal to it to get the
corresponding positive value.
This is rather theoretical as it would require a mode where the
hsync+back porch is very long and the active+front porch very short.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
PIPECONF_INTERLACE_W_FIELD_INDICATION is only meant to be used for sdvo
since it implies a slightly weird vsync shift of htotal/2. For everything
else we should use PIPECONF_INTERLACE_W_SYNC_SHIFT and let the value in
the VSYNCSHIFT register take effect.
The only exception is gen3 simply because VSYNCSHIFT didn't exist yet.
Gen2 doesn't support interlaced modes at all, so we can drop the
explicit gen2 checks.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
When interlaced sdvo output is used, vsyncshift should supposedly
be (htotal-1)/2. In reality PIPECONF/TRANSCONF will override it by
using the legacy vsyncshift interlace mode which causes the hardware
to ignore the VSYNCSHIFT register.
The only odd thing here is that on PCH platforms we program the
VSYNCSHIFT on both CPU and PCH, and it's not entirely clear if both
sides have to agree on the value or not. On the CPU side there's no
way to override the value via PIPECONF anymore, so if we want to make
the CPU side agree with the PCH side, we should probably program the
approriate value into VSYNCSHIFT manually. So let's do that, but for
now leave the PCH side to still use the legacy interlace mode in
TRANSCONF.
We can also drop the gen2 check since gen2 doesn't support interlaced
modes at all.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This makes HDMI testers happier on VLV platforms. It may be that we
need it for any non-SVO platform, but I don't have any tests to back
that up, so I'm leaving other pre-ILK platforms alone for now.
Tested-by: "Clint Taylor <clinton.a.taylor@intel.com>"
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=74964
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We want future generations to at least attempt to use all features, so
restrict the stolen memory disabling when vt-d is enabled to the
latest generation we have reports for. Which is a HSW per the original
report.
Also once we get a bit a hold of some of the mysterious framebuffer in
stolen memory issues that still haunt bugzilla, we should probably
drop this hack again and see what happens.
This was introduced in
commit 0f4706d274
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Tue Mar 18 14:50:50 2014 +0200
drm/i915: Disable stolen memory when DMAR is active
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
References: https://bugs.freedesktop.org/show_bug.cgi?id=68535
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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Merge tag 'v3.14' into drm-intel-next-queued
Linux 3.14
The vt-d w/a merged late in 3.14-rc needs a bit of fine-tuning, hence
backmerge.
Conflicts:
drivers/gpu/drm/i915/i915_gem_gtt.c
drivers/gpu/drm/i915/intel_ddi.c
drivers/gpu/drm/i915/intel_dp.c
All trivial adjacent lines changed type conflicts, so trivial git
doesn't even show them in the merg commit.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Pull vfs fixes from Al Viro:
"Switch mnt_hash to hlist, turning the races between __lookup_mnt() and
hash modifications into false negatives from __lookup_mnt() (instead
of hangs)"
On the false negatives from __lookup_mnt():
"The *only* thing we care about is not getting stuck in __lookup_mnt().
If it misses an entry because something in front of it just got moved
around, etc, we are fine. We'll notice that mount_lock mismatch and
that'll be it"
* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
switch mnt_hash to hlist
don't bother with propagate_mnt() unless the target is shared
keep shadowed vfsmounts together
resizable namespace.c hashes
I am the new kernel tree Documentation maintainer (except for parts that
are handled by other people, of course).
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull input updates from Dmitry Torokhov:
"Some more updates for the input subsystem.
You will get a fix for race in mousedev that has been causing quite a
few oopses lately and a small fixup for force feedback support in
evdev"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: mousedev - fix race when creating mixed device
Input: don't modify the id of ioctl-provided ff effect on upload failure
It its possible to configure your PAM stack to refuse login if audit
messages (about the login) were unable to be sent. This is common in
many distros and thus normal configuration of many containers. The PAM
modules determine if audit is enabled/disabled in the kernel based on
the return value from sending an audit message on the netlink socket.
If userspace gets back ECONNREFUSED it believes audit is disabled in the
kernel. If it gets any other error else it refuses to let the login
proceed.
Just about ever since the introduction of namespaces the kernel audit
subsystem has returned EPERM if the task sending a message was not in
the init user or pid namespace. So many forms of containers have never
worked if audit was enabled in the kernel.
BUT if the container was not in net_init then the kernel network code
would send ECONNREFUSED (instead of the audit code sending EPERM). Thus
by pure accident/dumb luck/bug if an admin configured the PAM stack to
reject all logins that didn't talk to audit, but then ran the login
untility in the non-init_net namespace, it would work!! Clearly this was
a bug, but it is a bug some people expected.
With the introduction of network namespace support in 3.14-rc1 the two
bugs stopped cancelling each other out. Now, containers in the
non-init_net namespace refused to let users log in (just like PAM was
configfured!) Obviously some people were not happy that what used to let
users log in, now didn't!
This fix is kinda hacky. We return ECONNREFUSED for all non-init
relevant namespaces. That means that not only will the old broken
non-init_net setups continue to work, now the broken non-init_pid or
non-init_user setups will 'work'. They don't really work, since audit
isn't logging things. But it's what most users want.
In 3.15 we should have patches to support not only the non-init_net
(3.14) namespace but also the non-init_pid and non-init_user namespace.
So all will be right in the world. This just opens the doors wide open
on 3.14 and hopefully makes users happy, if not the audit system...
Reported-by: Andre Tomt <andre@tomt.net>
Reported-by: Adam Richter <adam_richter2004@yahoo.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use cmpxchg() to atomically set i_flags instead of clearing out the
S_IMMUTABLE, S_APPEND, etc. flags and then setting them from the
EXT4_IMMUTABLE_FL, EXT4_APPEND_FL flags, since this opens up a race
where an immutable file has the immutable flag cleared for a brief
window of time.
Reported-by: John Sullivan <jsrhbz@kanargh.force9.co.uk>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fixes RCU bug - walking through hlist is safe in face of element moves,
since it's self-terminating. Cyclic lists are not - if we end up jumping
to another hash chain, we'll loop infinitely without ever hitting the
original list head.
[fix for dumb braino folded]
Spotted by: Max Kellermann <mk@cm4all.com>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If the dest_mnt is not shared, propagate_mnt() does nothing -
there's no mounts to propagate to and thus no copies to create.
Might as well don't bother calling it in that case.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
