Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted

Pull media updates from Mauro Carvalho Chehab:

 - v4l2-core: added ISP statistics support and per-block validation

 - v4l2-core: Allow unknown HDR10 white point and luminance

 - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor

 - New codec: Milos: VPU v2.0 codec support

 - isp driver: gained support for Dreamchip RPPX1 ISP framework

 - vsp1 driver: gained support for RZ/T2H and RZ/N2H

 - Novalake driver: gained CVS support for new NVL hardware

 - dvb-core: fix feed leak on failed DMX_ADD_PID

 - several driver fixes, cleanups and minor improvements

* tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits)
  media: ipu-bridge: check all DMI entries when overriding sensor rotation
  media: v4l2-async: avoid deleting unlinked ASC entry on link error
  media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement
  media: intel/ipu6: fix async notifier cleanup leak on parse error
  media: staging/ipu7: fix async notifier UAF on probe error path
  media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path
  media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem()
  media: rcar-isp: Fix VSPX reference leaks
  media: rcar-isp: Release ISPCORE resources
  media: i2c: imx415: Release runtime PM reference on VBLANK error
  media: i2c: imx415: Return test pattern write errors
  media: renesas: vsp1: Declare index variables in for loop statement
  media: renesas: vsp1: Make reset control optional to support platforms without a reset line
  media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs
  media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs
  media: nxp: imx8-isi: Add additional 32-bit RGB format support
  media: nxp: imx8-isi: Add 16-bit raw Bayer format support
  media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams
  media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks
  media: nxp: imx8-isi: Correct color map between V4L2 and ISI
  ...

1 files changed, 114 insertions, 0 deletions

diff --git a/Documentation/admin-guide/device-mapper/writecache.rst b/Documentation/admin-guide/device-mapper/writecache.rst
new file mode 100644
index 000000000..60c16b7fd
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+++ b/Documentation/admin-guide/device-mapper/writecache.rst
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+=================
+Writecache target
+=================
+
+The writecache target caches writes on persistent memory or on SSD. It
+doesn't cache reads because reads are supposed to be cached in page cache
+in normal RAM.
+
+When the device is constructed, the first sector should be zeroed or the
+first sector should contain valid superblock from previous invocation.
+
+Constructor parameters:
+
+1. type of the cache device - "p" or "s"
+	- p - persistent memory
+	- s - SSD
+2. the underlying device that will be cached
+3. the cache device
+4. block size (4096 is recommended; the maximum block size is the page
+   size)
+5. the number of optional parameters (the parameters with an argument
+   count as two)
+
+	start_sector n		(default: 0)
+		offset from the start of cache device in 512-byte sectors
+	high_watermark n	(default: 50)
+		start writeback when the number of used blocks reach this
+		watermark
+	low_watermark x		(default: 45)
+		stop writeback when the number of used blocks drops below
+		this watermark
+	writeback_jobs n	(default: unlimited)
+		limit the number of blocks that are in flight during
+		writeback. Setting this value reduces writeback
+		throughput, but it may improve latency of read requests
+	autocommit_blocks n	(default: 64 for pmem, 65536 for ssd)
+		when the application writes this amount of blocks without
+		issuing the FLUSH request, the blocks are automatically
+		committed
+	autocommit_time ms	(default: 1000)
+		autocommit time in milliseconds. The data is automatically
+		committed if this time passes and no FLUSH request is
+		received
+	fua			(by default on)
+		applicable only to persistent memory - use the FUA flag
+		when writing data from persistent memory back to the
+		underlying device
+	nofua
+		applicable only to persistent memory - don't use the FUA
+		flag when writing back data and send the FLUSH request
+		afterwards
+
+		- some underlying devices perform better with fua, some
+		  with nofua. The user should test it
+	cleaner
+		when this option is activated (either in the constructor
+		arguments or by a message), the cache will not promote
+		new writes (however, writes to already cached blocks are
+		promoted, to avoid data corruption due to misordered
+		writes) and it will gradually writeback any cached
+		data. The userspace can then monitor the cleaning
+		process with "dmsetup status". When the number of cached
+		blocks drops to zero, userspace can unload the
+		dm-writecache target and replace it with dm-linear or
+		other targets.
+	max_age n
+		specifies the maximum age of a block in milliseconds. If
+		a block is stored in the cache for too long, it will be
+		written to the underlying device and cleaned up.
+	metadata_only
+		only metadata is promoted to the cache. This option
+		improves performance for heavier REQ_META workloads.
+	pause_writeback n	(default: 3000)
+		pause writeback if there was some write I/O redirected to
+		the origin volume in the last n milliseconds
+
+Status:
+
+1. error indicator - 0 if there was no error, otherwise error number
+2. the number of blocks
+3. the number of free blocks
+4. the number of blocks under writeback
+5. the number of read blocks
+6. the number of read blocks that hit the cache
+7. the number of write blocks
+8. the number of write blocks that hit uncommitted block
+9. the number of write blocks that hit committed block
+10. the number of write blocks that bypass the cache
+11. the number of write blocks that are allocated in the cache
+12. the number of write requests that are blocked on the freelist
+13. the number of flush requests
+14. the number of discarded blocks
+
+Messages:
+	flush
+		Flush the cache device. The message returns successfully
+		if the cache device was flushed without an error
+	flush_on_suspend
+		Flush the cache device on next suspend. Use this message
+		when you are going to remove the cache device. The proper
+		sequence for removing the cache device is:
+
+		1. send the "flush_on_suspend" message
+		2. load an inactive table with a linear target that maps
+		   to the underlying device
+		3. suspend the device
+		4. ask for status and verify that there are no errors
+		5. resume the device, so that it will use the linear
+		   target
+		6. the cache device is now inactive and it can be deleted
+	cleaner
+		See above "cleaner" constructor documentation.
+	clear_stats
+		Clear the statistics that are reported on the status line