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Make the ops->init_rreq() callback optional. This isn't required for the
erofs changes I'm implementing to do on-demand read through fscache[1].
Further, ceph has an empty init_rreq method that can then be removed and
it's marked optional in the documentation.
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/20211227125444.21187-1-jefflexu@linux.alibaba.com/ [1]
Link: https://lore.kernel.org/r/20211228124419.103020-1-jefflexu@linux.alibaba.com
Link: https://lore.kernel.org/r/164251410387.3435901.2504600788262093313.stgit@warthog.procyon.org.uk/ # v1
Add a comment into fscache_note_page_release() to explain how the
page-release optimisation logic works[1]. It's not entirely obvious as it
has nothing to do with whether or not the netfs file contains data.
FSCACHE_COOKIE_NO_DATA_TO_READ is set if we have no data in the cache yet
(ie. the backing file lookup was negative, the file is 0 length or the
cookie got invalidated). It means that we have no data in the cache, not
that the file is necessarily empty on the server.
FSCACHE_COOKIE_HAVE_DATA is set once we've stored data in the backing file.
From that point on, we have data we *could* read - however, it's covered by
pages in the netfs pagecache until at such time one of those covering pages
is released.
So if we've written data to the cache (HAVE_DATA) and there wasn't any data
in the cache when we started (NO_DATA_TO_READ), it may no longer be true
that we can skip reading from the cache.
Read skipping is done by cachefiles_prepare_read().
Note that tracking is not done on a per-page basis, but only on a per-file
basis.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/043a206f03929c2667a465314144e518070a9b2d.camel@kernel.org/ [1]
Link: https://lore.kernel.org/r/164251408479.3435901.9540165422908194636.stgit@warthog.procyon.org.uk/ # v1
Add a check that the backing filesystem supports the creation of
tmpfiles[1].
Suggested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/568749bd7cc02908ecf6f3d6a611b6f9cf5c4afd.camel@kernel.org/ [1]
Link: https://lore.kernel.org/r/164251406558.3435901.1249023136670058162.stgit@warthog.procyon.org.uk/ # v1
Add a comment to explain the checks that cachefiles is making of the
backing filesystem[1].
Suggested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/568749bd7cc02908ecf6f3d6a611b6f9cf5c4afd.camel@kernel.org/ [1]
Link: https://lore.kernel.org/r/164251405621.3435901.771439791811515914.stgit@warthog.procyon.org.uk/ # v1
Add a tracepoint to log failure to apply an active mark to a file in
addition to tracing successfully setting and unsetting the mark.
Also include the backing file inode number in the message logged to dmesg.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/164251404666.3435901.17331742792401482190.stgit@warthog.procyon.org.uk/ # v1
Make some adjustments to tracepoints to make the tracing a bit more
followable:
(1) Standardise on displaying the backing inode number as "B=<hex>" with
no leading zeros.
(2) Make the cachefiles_lookup tracepoint log the directory inode number
as well as the looked-up inode number.
(3) Add a cachefiles_lookup tracepoint into cachefiles_get_directory() to
log directory lookup.
(4) Add a new cachefiles_mkdir tracepoint and use that to log a successful
mkdir from cachefiles_get_directory().
(5) Make the cachefiles_unlink and cachefiles_rename tracepoints log the
inode number of the affected file/dir rather than dentry struct
pointers.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/164251403694.3435901.9797725381831316715.stgit@warthog.procyon.org.uk/ # v1
fscache_acquire_cache() requires a non-empty name, while 'tag <name>'
command is optional for cachefilesd.
Thus set default tag name if it's unspecified to avoid the regression of
cachefilesd. The logic is the same with that before rewritten.
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/164251399914.3435901.4761991152407411408.stgit@warthog.procyon.org.uk/ # v1
Cachefiles keeps track of how much space is available on the backing
filesystem and refuses new writes permission to start if there isn't enough
(we especially don't want ENOSPC happening). It also tracks the amount of
data pending in DIO writes (cache->b_writing) and reduces the amount of
free space available by this amount before deciding if it can set up a new
write.
However, the old fscache I/O API was very much page-granularity dependent
and, as such, cachefiles's cache->bshift was meant to be a multiplier to
get from PAGE_SIZE to block size (ie. a blocksize of 512 would give a shift
of 3 for a 4KiB page) - and this was incorrectly being used to turn the
number of bytes in a DIO write into a number of blocks, leading to a
massive over estimation of the amount of data in flight.
Fix this by changing cache->bshift to be a multiplier from bytes to
blocksize and deal with quantities of blocks, not quantities of pages.
Fix also the rounding in the calculation in cachefiles_write() which needs
a "- 1" inserting.
Fixes: 047487c947e8 ("cachefiles: Implement the I/O routines")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/164251398954.3435901.7138806620218474123.stgit@warthog.procyon.org.uk/ # v1
The condition that the waits in fscache_wait_on_volume_collision() are
waiting until are inverted. This suddenly started happening on the
upstream kernel with something like the following appearing in dmesg when
running xfstests:
CacheFiles: cachefiles: Inode already in use: Iafs,example.com,100055
Fix them by inverting the conditions.
Fixes: 62ab63352350 ("fscache: Implement volume registration")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/164251398010.3435901.943876048104930939.stgit@warthog.procyon.org.uk/ # v1
Pull clk updates from Stephen Boyd:
"We have a couple patches in the framework core this time around but
they're mostly minor cleanups and some debugfs stuff. The real work
that's in here is the typical pile of clk driver updates and new SoC
support.
Per usual (or maybe just recent trends), Qualcomm gains a handful of
SoC drivers additions and has the largest diffstat. After that there
are quite a few updates to the Allwinner (sunxi) drivers to support
modular drivers and Renesas is heavily updated to add more support for
various clks.
Overall it looks pretty normal.
New Drivers:
- Add MDMA and BDMA clks to Ingenic JZ4760 and JZ4770
- MediaTek mt7986 SoC basic support
- Clock and reset driver for Toshiba Visconti SoCs
- Initial clock driver for the Exynos7885 SoC (Samsung Galaxy A8)
- Allwinner D1 clks
- Lan966x Generic Clock Controller driver and associated DT bindings
- Qualcomm SDX65, SM8450, and MSM8976 GCC clks
- Qualcomm SDX65 and SM8450 RPMh clks
Updates:
- Set suppress_bind_attrs to true for i.MX8ULP driver
- Switch from do_div to div64_ul for throughout all i.MX drivers
- Fix imx8mn_clko1_sels for i.MX8MN
- Remove unused IPG_AUDIO_ROOT from i.MX8MP
- Switch parent for audio_root_clk to audio ahb in i.MX8MP driver
- Removal of all remaining uses of __clk_lookup() in
drivers/clk/samsung
- Refactoring of the CPU clocks registration to use common interface
- An update of the Exynos850 driver (support for more clock domains)
required by the E850-96 development board
- Prep for runtime PM and generic power domains on Tegra
- Support modular Allwinner clk drivers via platform bus
- Lan966x clock driver extended to support clock gating
- Add serial (SCI1), watchdog (WDT), timer (OSTM), SPI (RSPI), and
thermal (TSU) clocks and resets on Renesas RZ/G2L
- Rework SDHI clock handling in the Renesas R-Car Gen3 and RZ/G2
clock drivers, and in the Renesas SDHI driver
- Make the Cortex-A55 (I) clock on Renesas RZ/G2L programmable
- Document support for the new Renesas R-Car S4-8 (R8A779F0) SoC
- Add support for the new Renesas R-Car S4-8 (R8A779F0) SoC
- Add GPU clock and resets on Renesas RZ/G2L
- Add clk-provider.h to various Qualcomm clk drivers
- devm version of clk_hw_register_gate()
- kerneldoc fixes in a couple drivers"
* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (131 commits)
clk: visconti: Remove pointless NULL check in visconti_pll_add_lookup()
clk: mediatek: add mt7986 clock support
clk: mediatek: add mt7986 clock IDs
dt-bindings: clock: mediatek: document clk bindings for mediatek mt7986 SoC
clk: mediatek: clk-gate: Use regmap_{set/clear}_bits helpers
clk: mediatek: clk-gate: Shrink by adding clockgating bit check helper
clk: x86: Fix clk_gate_flags for RV_CLK_GATE
clk: x86: Use dynamic con_id string during clk registration
ACPI: APD: Add a fmw property clk-name
drivers: acpi: acpi_apd: Remove unused device property "is-rv"
x86: clk: clk-fch: Add support for newer family of AMD's SOC
clk: ingenic: Add MDMA and BDMA clocks
dt-bindings: clk/ingenic: Add MDMA and BDMA clocks
clk: bm1880: remove kfrees on static allocations
clk: Drop unused COMMON_CLK_STM32MP157_SCMI config
clk: st: clkgen-mux: search reg within node or parent
clk: st: clkgen-fsyn: search reg within node or parent
clk: Enable/Disable runtime PM for clk_summary
MAINTAINERS: Add entries for Toshiba Visconti PLL and clock controller
clk: visconti: Add support common clock driver and reset driver
...
Pull LED updates from Pavel Machek:
"Nothing major is happening here"
* tag 'leds-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/pavel/linux-leds:
leds: lp55xx: initialise output direction from dts
ARM: dts: omap3-n900: Fix lp5523 for multi color
leds: ktd2692: Drop calling dev_of_node() in ktd2692_parse_dt
leds: lgm-sso: Get rid of duplicate of_node assignment
leds: tca6507: Get rid of duplicate of_node assignment
leds: leds-fsg: Drop FSG3 LED driver
leds: lp50xx: remove unused variable
dt-bindings: leds: Replace moonlight with indicator in mt6360 example
leds: led-core: Update fwnode with device_set_node
leds: tca6507: use swap() to make code cleaner
leds: Add mt6360 driver
dt-bindings: leds: Add bindings for MT6360 LED
- Add MDMA and BDMA clks to Ingenic JZ4760 and JZ4770
- MediaTek mt7986 SoC basic support
* clk-ingenic:
clk: ingenic: Add MDMA and BDMA clocks
dt-bindings: clk/ingenic: Add MDMA and BDMA clocks
* clk-mediatek:
clk: mediatek: add mt7986 clock support
clk: mediatek: add mt7986 clock IDs
dt-bindings: clock: mediatek: document clk bindings for mediatek mt7986 SoC
clk: mediatek: clk-gate: Use regmap_{set/clear}_bits helpers
clk: mediatek: clk-gate: Shrink by adding clockgating bit check helper
Pull devicetree updates from Rob Herring:
"Bindings:
- DT schema conversions for Samsung clocks, RNG bindings, Qcom
Command DB and rmtfs, gpio-restart, i2c-mux-gpio, i2c-mux-pinctl,
Tegra I2C and BPMP, pwm-vibrator, Arm DSU, and Cadence macb
- DT schema conversions for Broadcom platforms: interrupt
controllers, STB GPIO, STB waketimer, STB reset, iProc MDIO mux,
iProc PCIe, Cygnus PCIe PHY, PWM, USB BDC, BCM6328 LEDs, TMON,
SYSTEMPORT, AMAC, Northstar 2 PCIe PHY, GENET, moca PHY, GISB
arbiter, and SATA
- Add binding schemas for Tegra210 EMC table, TI DC-DC converters,
- Clean-ups of MDIO bus schemas to fix 'unevaluatedProperties' issues
- More fixes due to 'unevaluatedProperties' enabling
- Data type fixes and clean-ups of binding examples found in
preparation to move to validating DTB files directly (instead of
intermediate YAML representation.
- Vendor prefixes for T-Head Semiconductor, OnePlus, and Sunplus
- Add various new compatible strings
DT core:
- Silence a warning for overlapping reserved memory regions
- Reimplement unittest overlay tracking
- Fix stack frame size warning in unittest
- Clean-ups of early FDT scanning functions
- Fix handling of "linux,usable-memory-range" on EFI booted systems
- Add support for 'fail' status on CPU nodes
- Improve error message in of_phandle_iterator_next()
- kbuild: Disable duplicate unit-address warnings for disabled nodes"
* tag 'devicetree-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (114 commits)
dt-bindings: net: mdio: Drop resets/reset-names child properties
dt-bindings: clock: samsung: convert S5Pv210 to dtschema
dt-bindings: clock: samsung: convert Exynos5410 to dtschema
dt-bindings: clock: samsung: convert Exynos5260 to dtschema
dt-bindings: clock: samsung: extend Exynos7 bindings with UFS
dt-bindings: clock: samsung: convert Exynos7 to dtschema
dt-bindings: clock: samsung: convert Exynos5433 to dtschema
dt-bindings: i2c: maxim,max96712: Add bindings for Maxim Integrated MAX96712
dt-bindings: iio: adi,ltc2983: Fix 64-bit property sizes
dt-bindings: power: maxim,max17040: Fix incorrect type for 'maxim,rcomp'
dt-bindings: interrupt-controller: arm,gic-v3: Fix 'interrupts' cell size in example
dt-bindings: iio/magnetometer: yamaha,yas530: Fix invalid 'interrupts' in example
dt-bindings: clock: imx5: Drop clock consumer node from example
dt-bindings: Drop required 'interrupt-parent'
dt-bindings: net: ti,dp83869: Drop value on boolean 'ti,max-output-impedance'
dt-bindings: net: wireless: mt76: Fix 8-bit property sizes
dt-bindings: PCI: snps,dw-pcie-ep: Drop conflicting 'max-functions' schema
dt-bindings: i2c: st,stm32-i2c: Make each example a separate entry
dt-bindings: net: stm32-dwmac: Make each example a separate entry
dt-bindings: net: Cleanup MDIO node schemas
...
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