Audit all the users of dma_resv_add_excl_fence() and make sure they
reserve a shared slot also when only trying to add an exclusive fence.

This is the next step towards handling the exclusive fence like a
shared one.

v2: fix missed case in amdgpu
v3: and two more radeon, rename function
v4: add one more case to TTM, fix i915 after rebase
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220406075132.3263-2-christian.koenig@amd.com

Those macros are really about the HVS itself, and thus its associated
structure vc4_hvs, rather than the entire (virtual) vc4 device.

Let's change those macros to use the hvs pointer directly, and change
the calling sites accordingly.
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20220331143744.777652-8-maxime@cerno.tech

atomic_flush will be called for each CRTC even if they aren't enabled.

The whole code we have there will thus run without a properly affected
channel, which can then result in all sorts of weird behaviour.

Fortunately, the DRM_PLANE_COMMIT_ACTIVE_ONLY flag will skip the CRTC
atomic_begin and atomic_flush, and the planes atomic_update, if they
aren't enabled.

Our plane atomic_update is a nop, and atomic_begin will copy the current
HVS channel to the vc4_crtc structure for the interrupt handler to
consume, but the handler won't run if the CRTC is disabled. So in the
end, it will only skip our CRTC atomic_flush, which is what we want.
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20220331143744.777652-7-maxime@cerno.tech

The vc4_hvs_update_dlist function mostly deals with setting up the
vblank events and setting up the dlist entry pointer to our current
active one.

We'll want to do the former separately from the vblank handling in later
patches, so let's move it to a function of its own.
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20220331143744.777652-6-maxime@cerno.tech

Setting the DISPLISTx register needs to occur in every case, and we
don't need to protect the register using the event_lock, so we can just
move it after the if branches and simplify a bit the function.
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20220331143744.777652-5-maxime@cerno.tech

The assigned_channel field of our vc4_crtc_state structure is accessed
multiple times in vc4_hvs_atomic_flush, so let's move it to a variable
that can be used in all those places.
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20220331143744.777652-4-maxime@cerno.tech

In order to get the field currently being output, the driver has been
using the display FIFO frame count in the HVS, reading a 6-bit field at
the offset 12 in the DISPSTATx register.

While that field is indeed at that location for the FIFO 1 and 2, the
one for the FIFO0 is actually in the DISPSTAT1 register, at the offset
18.

Fixes: e538092c ("drm/vc4: Enable precise vblank timestamping for interlaced modes.")
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20220331143744.777652-3-maxime@cerno.tech

During a commit, the core clock, which feeds the HVS, needs to run at
a minimum of 500MHz.

While doing that commit, we can also change the mode to one that
requires a higher core clock, so we take the core clock rate associated
to that new state into account for that boost.

However, the old state also needs to be taken into account if it
requires a core clock higher that the new one and our 500MHz limit,
since it's still live in hardware at the beginning of our commit.

Fixes: 16e10105 ("drm/vc4: Increase the core clock based on HVS load")
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20220331143744.777652-2-maxime@cerno.tech

Now that the clock driver makes sure we never end up with a rate of 0,
the HDMI driver doesn't need to care anymore.
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20220225143534.405820-13-maxime@cerno.tech

The HVS core clock isn't really obvious, so let's add a bunch more
comments and some logging for easier debugging.
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Acked-by: NThomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20220225143534.405820-12-maxime@cerno.tech

The module owner = THIS_MODULE is set by I2C core, drop duplicate assignment.

Fixes: 8dde6f74 ("drm: bridge: icn6211: Add I2C configuration support")
Signed-off-by: NMarek Vasut <marex@denx.de>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
To: dri-devel@lists.freedesktop.org
Reviewed-by: NJagan Teki <jagan@amarulasolutions.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220401113317.7033-1-marex@denx.de

Instead of exiting the loop as expected when an entry is found, the
list_for_each_entry() continues until the traversal is complete.
when found the entry, add a break after the switch statement.
Signed-off-by: NXiaomeng Tong <xiam0nd.tong@gmail.com>
Signed-off-by: NPatrik Jakobsson <patrik.r.jakobsson@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220401115018.9335-1-xiam0nd.tong@gmail.com

Fix copy-paste error, module exit function should be marked with __exit
instead of __init.

Fixes: 8dde6f74 ("drm: bridge: icn6211: Add I2C configuration support")
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NMarek Vasut <marex@denx.de>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
To: dri-devel@lists.freedesktop.org
Signed-off-by: NRobert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220406014250.902187-1-marex@denx.deReviewed-by: NRobert Foss <robert.foss@linaro.org>

The datasheet for this bridge is not available, the PLL behavior has been
inferred from [1] and [2] and by analyzing the DPI pixel clock with scope.
After further testing with other displays and different DSI data lane count,
it turns out the P-factor is not 1/2^N divider, but rather only 1/N divider.
It also turns out the input into the PLL seem to be ByteClock instead of DSI
HS clock.

Rework the P-factor calculation such that the PLL calculation code handles
P-factor from 1..32 with P-factors above 16 must be even. In case P-factor
is even, enable built-in 1:2 divider and program P-factor/2 to PLL_REF_DIV,
otherwise configure only the P-factor into PLL_REF_DIV register.

Switch the PLL factor calculation from kHz to Hz to maintain precision.

[1] https://github.com/rockchip-linux/kernel/blob/develop-4.19/drivers/gpu/drm/bridge/icn6211.c
[2] https://github.com/tdjastrzebski/ICN6211-Configurator

Fixes: f30cf0ec ("drm: bridge: icn6211: Add generic DSI-to-DPI PLL configuration")
Signed-off-by: NMarek Vasut <marex@denx.de>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
To: dri-devel@lists.freedesktop.org
Acked-by: NMaxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220402004118.897014-1-marex@denx.de

Following the introduction of bridge_atomic_enable in the ingenic
drm driver, the crtc is enabled between .prepare and .enable, if
it exists. Add it so the backlight is only enabled after the crtc is, to
avoid graphical issues.

As we're moving the "sleep out" command out of the init sequence
into .enable for the ABT, we need to switch the regmap cache
to REGCACHE_FLAT to be able to use regmap_set_bits, given this
panel registers are write-ony and read as 0.
Signed-off-by: NChristophe Branchereau <cbranchereau@gmail.com>
Signed-off-by: NPaul Cercueil <paul@crapouillou.net>
[pcercuei: Remove empty line after opening brace]
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220321133651.291592-4-cbranchereau@gmail.com

This driver supports the NewVision NV3052C based LCDs. Right now, it
only supports the LeadTek LTK035C5444T 2.4" 640x480 TFT LCD panel, which
can be found in the Anbernic RG-350M handheld console.
Signed-off-by: NChristophe Branchereau <cbranchereau@gmail.com>
Signed-off-by: NPaul Cercueil <paul@crapouillou.net>
[pcercuei: Change msleep(5) to usleep_range(5000, 20000)]
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220321133651.291592-3-cbranchereau@gmail.com

ingenic_drm_bridge_atomic_enable allows the CRTC to be enabled after
panels have slept out, and before their display is turned on, solving
a graphical bug on the newvision nv3502c.

Also add ingenic_drm_bridge_atomic_disable to balance it out.
Signed-off-by: NChristophe Branchereau <cbranchereau@gmail.com>
Signed-off-by: NPaul Cercueil <paul@crapouillou.net>
Acked-by: NArtur Rojek <contact@artur-rojek.eu>
Link: https://patchwork.freedesktop.org/patch/msgid/20220321133651.291592-2-cbranchereau@gmail.com

Use dma_resv_get_singleton() here to eventually get more than one write
fence as single fence.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Lyude Paul <lyude@redhat.com>
Cc: nouveau@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220321135856.1331-14-christian.koenig@amd.com

Drivers should never touch this directly.

v2: fix rebase clash
Signed-off-by: NChristian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220321135856.1331-10-christian.koenig@amd.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Instead use the new dma_resv_get_singleton function.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Karol Herbst <kherbst@redhat.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: nouveau@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220321135856.1331-6-christian.koenig@amd.com

The bug is here:
	if (nvkm_cstate_valid(clk, cstate, max_volt, clk->temp))
		return cstate;

The list iterator value 'cstate' will *always* be set and non-NULL
by list_for_each_entry_from_reverse(), so it is incorrect to assume
that the iterator value will be unchanged if the list is empty or no
element is found (In fact, it will be a bogus pointer to an invalid
structure object containing the HEAD). Also it missed a NULL check
at callsite and may lead to invalid memory access after that.

To fix this bug, just return 'encoder' when found, otherwise return
NULL. And add the NULL check.

Cc: stable@vger.kernel.org
Fixes: 1f7f3d91 ("drm/nouveau/clk: Respect voltage limits in nvkm_cstate_prog")
Signed-off-by: NXiaomeng Tong <xiam0nd.tong@gmail.com>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Signed-off-by: NLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220327075824.11806-1-xiam0nd.tong@gmail.com

It looks like the incorrect name of a function parameter was used
in the kernel-doc notation, so just change it to the function's
parameter name to quell the kernel-doc warning.

drivers/gpu/drm/drm_format_helper.c:640: warning: Function parameter or member 'vaddr' not described in 'drm_fb_xrgb8888_to_mono_reversed'
drivers/gpu/drm/drm_format_helper.c:640: warning: Excess function parameter 'src' description in 'drm_fb_xrgb8888_to_mono_reversed'

Fixes: bcf8b616 ("drm/format-helper: Add drm_fb_xrgb8888_to_mono_reversed()")
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
CC: Maxime Ripard <mripard@kernel.org>
CC: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: NSimon Ser <contact@emersion.fr>
Reviewed-by: NJavier Martinez Canillas <javierm@redhat.com>
Signed-off-by: NSimon Ser <contact@emersion.fr>
Link: https://patchwork.freedesktop.org/patch/480560/

You really need to hold the reservation here or all kinds of funny
things can happen between grabbing the dependencies and inserting the
new fences.

v2: Fix commit summary (Christian)
Acked-by: NMelissa Wen <mwen@igalia.com>
Reviewed-by: N"Christian König" <christian.koenig@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Luben Tuikov <luben.tuikov@amd.com>
Cc: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220331204651.2699107-4-daniel.vetter@ffwll.ch

Integrated into the scheduler now and all users converted over.

v2: Rebased over changes from König.
Acked-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220331204651.2699107-3-daniel.vetter@ffwll.ch

We need to pull the drm_sched_job_init much earlier, but that's very
minor surgery.

v2: Actually fix up cleanup paths by calling drm_sched_job_init, which
I wanted to to in the previous round (and did, for all other drivers).
Spotted by Lucas.

v3: Rebase over renamed functions to add dependencies.

v4: Rebase over patches from Christian.

v5: More rebasing over work from Christian.
Acked-by: NLucas Stach <l.stach@pengutronix.de>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Russell King <linux+etnaviv@armlinux.org.uk>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: etnaviv@lists.freedesktop.org
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220331204651.2699107-2-daniel.vetter@ffwll.ch

Since this driver has been changed to use the resource managed
devm_drm_of_get_bridge() to get bridge from ->attach(), it's
unnecessary to call drm_of_panel_bridge_remove() to remove the
bridge from ->detach().  So, let's drop the drm_of_panel_bridge_remove()
function call.  As nwl_dsi_bridge_detach() only calls
drm_of_panel_bridge_remove(), it can also be dropped.

Cc: Robert Foss <robert.foss@linaro.org>
Cc: Guido Günther <agx@sigxcpu.org>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Signed-off-by: NLiu Ying <victor.liu@nxp.com>
Reviewed-by: NJagan Teki <jagan@amarulasolutions.com>
Signed-off-by: NRobert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220401015828.2959505-1-victor.liu@nxp.com

This driver has been changed to use the resource managed
devm_drm_of_get_bridge() to get bridge from ->bind(), it's
unnecessary to call drm_of_panel_bridge_remove() to remove the
bridge from ->unbind() as devm_drm_of_get_bridge()
is automatically remove the bridge when @dev is unbound.

Drop it the drm_bridge_remove().

Cc: Linus Walleij <linus.walleij@linaro.org>
Reported-by: NMaxime Ripard <maxime@cerno.tech>
Signed-off-by: NJagan Teki <jagan@amarulasolutions.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NRobert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220401150533.7777-1-jagan@amarulasolutions.com

Makes the code a bit more simpler.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Cc: amd-gfx@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220321135856.1331-15-christian.koenig@amd.com

Use dma_resv_get_singleton() here to eventually get more than one write
fence as single fence.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220321135856.1331-13-christian.koenig@amd.com

Get the write fence using dma_resv_for_each_fence instead of accessing
it manually.

v2: add TODO comment
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Cc: amd-gfx@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220321135856.1331-9-christian.koenig@amd.com

Instead use the new dma_resv_get_singleton function.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Cc: amd-gfx@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220321135856.1331-8-christian.koenig@amd.com

Instead use the new dma_resv_get_singleton function.

v2: drop the TODO comment.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NZack Rusin <zackr@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220321135856.1331-7-christian.koenig@amd.com

Add a function to simplify getting a single fence for all the fences in
the dma_resv object.

v2: fix ref leak in error handling
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220321135856.1331-3-christian.koenig@amd.com

Signed-off-by: NSui Jingfeng <15330273260@189.cn>
Link: https://patchwork.freedesktop.org/patch/msgid/20220402134413.1705246-1-15330273260@189.cnReviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NChristian König <christian.koenig@amd.com>

This reverts commit 7dabfa2b. There are
multiple reports that this breaks boot on various systems. The common
theme is that orphan clks are having rates set on them when that isn't
expected. Let's revert it out for now so that -rc1 boots.
Reported-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Reported-by: NTony Lindgren <tony@atomide.com>
Reported-by: NAlexander Stein <alexander.stein@ew.tq-group.com>
Reported-by: NNaresh Kamboju <naresh.kamboju@linaro.org>
Link: https://lore.kernel.org/r/366a0232-bb4a-c357-6aa8-636e398e05eb@samsung.com
Cc: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: NStephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20220403022818.39572-1-sboyd@kernel.org

This reverts commit 6d35d04a.

Both Gabriel and Borislav report that this commit casues a regression
with nbd:

sysfs: cannot create duplicate filename '/dev/block/43:0'

Revert it before 5.18-rc1 and we'll investigage this separately in
due time.

Link: https://lore.kernel.org/all/YkiJTnFOt9bTv6A2@zn.tnic/Reported-by: NGabriel L. Somlo <somlo@cmu.edu>
Reported-by: NBorislav Petkov <bp@alien8.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Add a parameter called "extra_pages" for ttm_tt_init, to indicate that
driver needs extra pages in ttm_tt.

v2:
  Used imperative wording [Thomas and Christian]
Signed-off-by: NRamalingam C <ramalingam.c@intel.com>
cc: Christian Koenig <christian.koenig@amd.com>
cc: Hellstrom Thomas <thomas.hellstrom@intel.com>
Reviewed-by: NThomas Hellstrom <thomas.hellstrom@linux.intel.com>
Reviewed-by: NChristian Konig <christian.koenig@amd.com>
Reviewed-by: NNirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220401123751.27771-8-ramalingam.c@intel.com

Expanded testing of DM's bio polling support (using more fio threads
to dm-linear ontop of null_blk) exposed the possibility for polled
bios to hang (repeatedly polling in io_uring) when null_blk responds
with BLK_STS_AGAIN (due to lack of resources):

1) io_complete_rw_iopoll() is called from blkdev_bio_end_io_async() to
   notify kiocb is done, that is the completion interface between block
   layer and io_uring

2) io_complete_rw_iopoll() is called from io_do_iopoll()

3) dm returns BLK_STS_AGAIN for one bio (on behalf of underlying
   driver), then io_complete_rw_iopoll is called, but io_do_iopoll()
   doesn't handle -EAGAIN at all (due to logic in io_rw_should_reissue)

4) reason for dm's BLK_STS_AGAIN is underlying null_blk driver ran out
   of requests (easier to reproduce by setting low hw_queue_depth).

5) dm should handle BLK_STS_AGAIN for POLLED underlying IO, and may
   retry in dm layer.

This fix adds REQ_POLLED specific BLK_STS_AGAIN handling to
dm_io_complete() that clears REQ_POLLED and requeues the bio to DM
using queue_io().

Fixes: b99fdcdc ("dm: support bio polling")
Signed-off-by: NMing Lei <ming.lei@redhat.com>
[snitzer: revised header, reused dm_io_complete's REQ_POLLED case]
Signed-off-by: NMike Snitzer <snitzer@kernel.org>

Early alpha processors cannot write a single byte or short; they read 8
bytes, modify the value in registers and write back 8 bytes.

This could cause race condition in the structure dm_io - if the fields
flags and io_count are modified simultaneously.

Fix this bug by using 32-bit flags if we are on Alpha and if we are
compiling for a processor that doesn't have the byte-word-extension.
Signed-off-by: NMikulas Patocka <mpatocka@redhat.com>
Fixes: bd4a6dd2 ("dm: reduce size of dm_io and dm_target_io structs")
[snitzer: Jens allowed this change since Mikulas owns a relevant Alpha!]
Acked-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NMike Snitzer <snitzer@kernel.org>

The code modifying the EDID block should not need to do tricks to fix
the checksum. We have a function for computing the checksum, use it.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/5a11435419d804a58ef356c0b9acf445cffc1354.1648752228.git.jani.nikula@intel.com