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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
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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 ...
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+What: /sys/class/bdi/<bdi>/
+Date: January 2008
+Contact: Peter Zijlstra <a.p.zijlstra@chello.nl>
+Description:
+
+Provide a place in sysfs for the backing_dev_info object. This allows
+setting and retrieving various BDI specific variables.
+
+The <bdi> identifier can be either of the following:
+
+MAJOR:MINOR
+
+ Device number for block devices, or value of st_dev on
+ non-block filesystems which provide their own BDI, such as NFS
+ and FUSE.
+
+MAJOR:MINOR-fuseblk
+
+ Value of st_dev on fuseblk filesystems.
+
+default
+
+ The default backing dev, used for non-block device backed
+ filesystems which do not provide their own BDI.
+
+What: /sys/class/bdi/<bdi>/read_ahead_kb
+Date: January 2008
+Contact: Peter Zijlstra <a.p.zijlstra@chello.nl>
+Description:
+ Size of the read-ahead window in kilobytes
+
+ (read-write)
+What: /sys/class/bdi/<bdi>/min_ratio
+Date: January 2008
+Contact: Peter Zijlstra <a.p.zijlstra@chello.nl>
+Description:
+ Under normal circumstances each device is given a part of the
+ total write-back cache that relates to its current average
+ writeout speed in relation to the other devices.
+
+ The 'min_ratio' parameter allows assigning a minimum
+ percentage of the write-back cache to a particular device.
+ For example, this is useful for providing a minimum QoS.
+
+ (read-write)
+
+What: /sys/class/bdi/<bdi>/min_ratio_fine
+Date: November 2022
+Contact: Stefan Roesch <shr@devkernel.io>
+Description:
+ Under normal circumstances each device is given a part of the
+ total write-back cache that relates to its current average
+ writeout speed in relation to the other devices.
+
+ The 'min_ratio_fine' parameter allows assigning a minimum reserve
+ of the write-back cache to a particular device. The value is
+ expressed as part of 1 million. For example, this is useful for
+ providing a minimum QoS.
+
+ (read-write)
+
+What: /sys/class/bdi/<bdi>/max_ratio
+Date: January 2008
+Contact: Peter Zijlstra <a.p.zijlstra@chello.nl>
+Description:
+ Allows limiting a particular device to use not more than the
+ given percentage of the write-back cache. This is useful in
+ situations where we want to avoid one device taking all or
+ most of the write-back cache. For example in case of an NFS
+ mount that is prone to get stuck, or a FUSE mount which cannot
+ be trusted to play fair.
+
+ (read-write)
+
+What: /sys/class/bdi/<bdi>/max_ratio_fine
+Date: November 2022
+Contact: Stefan Roesch <shr@devkernel.io>
+Description:
+ Allows limiting a particular device to use not more than the
+ given value of the write-back cache. The value is given as part
+ of 1 million. This is useful in situations where we want to avoid
+ one device taking all or most of the write-back cache. For example
+ in case of an NFS mount that is prone to get stuck, or a FUSE mount
+ which cannot be trusted to play fair.
+
+ (read-write)
+
+What: /sys/class/bdi/<bdi>/min_bytes
+Date: October 2022
+Contact: Stefan Roesch <shr@devkernel.io>
+Description:
+ Under normal circumstances each device is given a part of the
+ total write-back cache that relates to its current average
+ writeout speed in relation to the other devices.
+
+ The 'min_bytes' parameter allows assigning a minimum
+ percentage of the write-back cache to a particular device
+ expressed in bytes.
+ For example, this is useful for providing a minimum QoS.
+
+ (read-write)
+
+What: /sys/class/bdi/<bdi>/max_bytes
+Date: October 2022
+Contact: Stefan Roesch <shr@devkernel.io>
+Description:
+ Allows limiting a particular device to use not more than the
+ given 'max_bytes' of the write-back cache. This is useful in
+ situations where we want to avoid one device taking all or
+ most of the write-back cache. For example in case of an NFS
+ mount that is prone to get stuck, a FUSE mount which cannot be
+ trusted to play fair, or a nbd device.
+
+ (read-write)
+
+What: /sys/class/bdi/<bdi>/strict_limit
+Date: October 2022
+Contact: Stefan Roesch <shr@devkernel.io>
+Description:
+ Forces per-BDI checks for the share of given device in the write-back
+ cache even before the global background dirty limit is reached. This
+ is useful in situations where the global limit is much higher than
+ affordable for given relatively slow (or untrusted) device. Turning
+ strictlimit on has no visible effect if max_ratio is equal to 100%.
+
+ (read-write)
+What: /sys/class/bdi/<bdi>/stable_pages_required
+Date: January 2008
+Contact: Peter Zijlstra <a.p.zijlstra@chello.nl>
+Description:
+ If set, the backing device requires that all pages comprising a write
+ request must not be changed until writeout is complete.
+
+ (read-only)