Pull 'struct fd' updates from Al Viro:
"Just the 'struct fd' layout change, with conversion to accessor
helpers"
* tag 'pull-stable-struct_fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
add struct fd constructors, get rid of __to_fd()
struct fd: representation change
introduce fd_file(), convert all accessors to it.
Pull MM updates from Andrew Morton:
"Along with the usual shower of singleton patches, notable patch series
in this pull request are:
- "Align kvrealloc() with krealloc()" from Danilo Krummrich. Adds
consistency to the APIs and behaviour of these two core allocation
functions. This also simplifies/enables Rustification.
- "Some cleanups for shmem" from Baolin Wang. No functional changes -
mode code reuse, better function naming, logic simplifications.
- "mm: some small page fault cleanups" from Josef Bacik. No
functional changes - code cleanups only.
- "Various memory tiering fixes" from Zi Yan. A small fix and a
little cleanup.
- "mm/swap: remove boilerplate" from Yu Zhao. Code cleanups and
simplifications and .text shrinkage.
- "Kernel stack usage histogram" from Pasha Tatashin and Shakeel
Butt. This is a feature, it adds new feilds to /proc/vmstat such as
$ grep kstack /proc/vmstat
kstack_1k 3
kstack_2k 188
kstack_4k 11391
kstack_8k 243
kstack_16k 0
which tells us that 11391 processes used 4k of stack while none at
all used 16k. Useful for some system tuning things, but
partivularly useful for "the dynamic kernel stack project".
- "kmemleak: support for percpu memory leak detect" from Pavel
Tikhomirov. Teaches kmemleak to detect leaksage of percpu memory.
- "mm: memcg: page counters optimizations" from Roman Gushchin. "3
independent small optimizations of page counters".
- "mm: split PTE/PMD PT table Kconfig cleanups+clarifications" from
David Hildenbrand. Improves PTE/PMD splitlock detection, makes
powerpc/8xx work correctly by design rather than by accident.
- "mm: remove arch_make_page_accessible()" from David Hildenbrand.
Some folio conversions which make arch_make_page_accessible()
unneeded.
- "mm, memcg: cg2 memory{.swap,}.peak write handlers" fro David
Finkel. Cleans up and fixes our handling of the resetting of the
cgroup/process peak-memory-use detector.
- "Make core VMA operations internal and testable" from Lorenzo
Stoakes. Rationalizaion and encapsulation of the VMA manipulation
APIs. With a view to better enable testing of the VMA functions,
even from a userspace-only harness.
- "mm: zswap: fixes for global shrinker" from Takero Funaki. Fix
issues in the zswap global shrinker, resulting in improved
performance.
- "mm: print the promo watermark in zoneinfo" from Kaiyang Zhao. Fill
in some missing info in /proc/zoneinfo.
- "mm: replace follow_page() by folio_walk" from David Hildenbrand.
Code cleanups and rationalizations (conversion to folio_walk())
resulting in the removal of follow_page().
- "improving dynamic zswap shrinker protection scheme" from Nhat
Pham. Some tuning to improve zswap's dynamic shrinker. Significant
reductions in swapin and improvements in performance are shown.
- "mm: Fix several issues with unaccepted memory" from Kirill
Shutemov. Improvements to the new unaccepted memory feature,
- "mm/mprotect: Fix dax puds" from Peter Xu. Implements mprotect on
DAX PUDs. This was missing, although nobody seems to have notied
yet.
- "Introduce a store type enum for the Maple tree" from Sidhartha
Kumar. Cleanups and modest performance improvements for the maple
tree library code.
- "memcg: further decouple v1 code from v2" from Shakeel Butt. Move
more cgroup v1 remnants away from the v2 memcg code.
- "memcg: initiate deprecation of v1 features" from Shakeel Butt.
Adds various warnings telling users that memcg v1 features are
deprecated.
- "mm: swap: mTHP swap allocator base on swap cluster order" from
Chris Li. Greatly improves the success rate of the mTHP swap
allocation.
- "mm: introduce numa_memblks" from Mike Rapoport. Moves various
disparate per-arch implementations of numa_memblk code into generic
code.
- "mm: batch free swaps for zap_pte_range()" from Barry Song. Greatly
improves the performance of munmap() of swap-filled ptes.
- "support large folio swap-out and swap-in for shmem" from Baolin
Wang. With this series we no longer split shmem large folios into
simgle-page folios when swapping out shmem.
- "mm/hugetlb: alloc/free gigantic folios" from Yu Zhao. Nice
performance improvements and code reductions for gigantic folios.
- "support shmem mTHP collapse" from Baolin Wang. Adds support for
khugepaged's collapsing of shmem mTHP folios.
- "mm: Optimize mseal checks" from Pedro Falcato. Fixes an mprotect()
performance regression due to the addition of mseal().
- "Increase the number of bits available in page_type" from Matthew
Wilcox. Increases the number of bits available in page_type!
- "Simplify the page flags a little" from Matthew Wilcox. Many legacy
page flags are now folio flags, so the page-based flags and their
accessors/mutators can be removed.
- "mm: store zero pages to be swapped out in a bitmap" from Usama
Arif. An optimization which permits us to avoid writing/reading
zero-filled zswap pages to backing store.
- "Avoid MAP_FIXED gap exposure" from Liam Howlett. Fixes a race
window which occurs when a MAP_FIXED operqtion is occurring during
an unrelated vma tree walk.
- "mm: remove vma_merge()" from Lorenzo Stoakes. Major rotorooting of
the vma_merge() functionality, making ot cleaner, more testable and
better tested.
- "misc fixups for DAMON {self,kunit} tests" from SeongJae Park.
Minor fixups of DAMON selftests and kunit tests.
- "mm: memory_hotplug: improve do_migrate_range()" from Kefeng Wang.
Code cleanups and folio conversions.
- "Shmem mTHP controls and stats improvements" from Ryan Roberts.
Cleanups for shmem controls and stats.
- "mm: count the number of anonymous THPs per size" from Barry Song.
Expose additional anon THP stats to userspace for improved tuning.
- "mm: finish isolate/putback_lru_page()" from Kefeng Wang: more
folio conversions and removal of now-unused page-based APIs.
- "replace per-quota region priorities histogram buffer with
per-context one" from SeongJae Park. DAMON histogram
rationalization.
- "Docs/damon: update GitHub repo URLs and maintainer-profile" from
SeongJae Park. DAMON documentation updates.
- "mm/vdpa: correct misuse of non-direct-reclaim __GFP_NOFAIL and
improve related doc and warn" from Jason Wang: fixes usage of page
allocator __GFP_NOFAIL and GFP_ATOMIC flags.
- "mm: split underused THPs" from Yu Zhao. Improve THP=always policy.
This was overprovisioning THPs in sparsely accessed memory areas.
- "zram: introduce custom comp backends API" frm Sergey Senozhatsky.
Add support for zram run-time compression algorithm tuning.
- "mm: Care about shadow stack guard gap when getting an unmapped
area" from Mark Brown. Fix up the various arch_get_unmapped_area()
implementations to better respect guard areas.
- "Improve mem_cgroup_iter()" from Kinsey Ho. Improve the reliability
of mem_cgroup_iter() and various code cleanups.
- "mm: Support huge pfnmaps" from Peter Xu. Extends the usage of huge
pfnmap support.
- "resource: Fix region_intersects() vs add_memory_driver_managed()"
from Huang Ying. Fix a bug in region_intersects() for systems with
CXL memory.
- "mm: hwpoison: two more poison recovery" from Kefeng Wang. Teaches
a couple more code paths to correctly recover from the encountering
of poisoned memry.
- "mm: enable large folios swap-in support" from Barry Song. Support
the swapin of mTHP memory into appropriately-sized folios, rather
than into single-page folios"
* tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (416 commits)
zram: free secondary algorithms names
uprobes: turn xol_area->pages[2] into xol_area->page
uprobes: introduce the global struct vm_special_mapping xol_mapping
Revert "uprobes: use vm_special_mapping close() functionality"
mm: support large folios swap-in for sync io devices
mm: add nr argument in mem_cgroup_swapin_uncharge_swap() helper to support large folios
mm: fix swap_read_folio_zeromap() for large folios with partial zeromap
mm/debug_vm_pgtable: Use pxdp_get() for accessing page table entries
set_memory: add __must_check to generic stubs
mm/vma: return the exact errno in vms_gather_munmap_vmas()
memcg: cleanup with !CONFIG_MEMCG_V1
mm/show_mem.c: report alloc tags in human readable units
mm: support poison recovery from copy_present_page()
mm: support poison recovery from do_cow_fault()
resource, kunit: add test case for region_intersects()
resource: make alloc_free_mem_region() works for iomem_resource
mm: z3fold: deprecate CONFIG_Z3FOLD
vfio/pci: implement huge_fault support
mm/arm64: support large pfn mappings
mm/x86: support large pfn mappings
...
Pull drm updates from Dave Airlie:
"This adds a couple of patches outside the drm core, all should be
acked appropriately, the string and pstore ones are the main ones that
come to mind.
Otherwise it's the usual drivers, xe is getting enabled by default on
some new hardware, we've changed the device number handling to allow
more devices, and we added some optional rust code to create QR codes
in the panic handler, an idea first suggested I think 10 years ago :-)
string:
- add mem_is_zero()
core:
- support more device numbers
- use XArray for minor ids
- add backlight constants
- Split dma fence array creation into alloc and arm
fbdev:
- remove usage of old fbdev hooks
kms:
- Add might_fault() to drm_modeset_lock priming
- Add dynamic per-crtc vblank configuration support
dma-buf:
- docs cleanup
buddy:
- Add start address support for trim function
printk:
- pass description to kmsg_dump
scheduler:
- Remove full_recover from drm_sched_start
ttm:
- Make LRU walk restartable after dropping locks
- Allow direct reclaim to allocate local memory
panic:
- add display QR code (in rust)
displayport:
- mst: GUID improvements
bridge:
- Silence error message on -EPROBE_DEFER
- analogix: Clean aup
- bridge-connector: Fix double free
- lt6505: Disable interrupt when powered off
- tc358767: Make default DP port preemphasis configurable
- lt9611uxc: require DRM_BRIDGE_ATTACH_NO_CONNECTOR
- anx7625: simplify OF array handling
- dw-hdmi: simplify clock handling
- lontium-lt8912b: fix mode validation
- nwl-dsi: fix mode vsync/hsync polarity
xe:
- Enable LunarLake and Battlemage support
- Introducing Xe2 ccs modifiers for integrated and discrete graphics
- rename xe perf to xe observation
- use wb caching on DGFX for system memory
- add fence timeouts
- Lunar Lake graphics/media/display workarounds
- Battlemage workarounds
- Battlemage GSC support
- GSC and HuC fw updates for LL/BM
- use dma_fence_chain_free
- refactor hw engine lookup and mmio access
- enable priority mem read for Xe2
- Add first GuC BMG fw
- fix dma-resv lock
- Fix DGFX display suspend/resume
- Use xe_managed for kernel BOs
- Use reserved copy engine for user binds on faulting devices
- Allow mixing dma-fence jobs and long-running faulting jobs
- fix media TLB invalidation
- fix rpm in TTM swapout path
- track resources and VF state by PF
i915:
- Type-C programming fix for MTL+
- FBC cleanup
- Calc vblank delay more accurately
- On DP MST, Enable LT fallback for UHBR<->non-UHBR rates
- Fix DP LTTPR detection
- limit relocations to INT_MAX
- fix long hangs in buddy allocator on DG2/A380
amdgpu:
- Per-queue reset support
- SDMA devcoredump support
- DCN 4.0.1 updates
- GFX12/VCN4/JPEG4 updates
- Convert vbios embedded EDID to drm_edid
- GFX9.3/9.4 devcoredump support
- process isolation framework for GFX 9.4.3/4
- take IOMMU mappings into account for P2P DMA
amdkfd:
- CRIU fixes
- HMM fix
- Enable process isolation support for GFX 9.4.3/4
- Allow users to target recommended SDMA engines
- KFD support for targetting queues on recommended SDMA engines
radeon:
- remove .load and drm_dev_alloc
- Fix vbios embedded EDID size handling
- Convert vbios embedded EDID to drm_edid
- Use GEM references instead of TTM
- r100 cp init cleanup
- Fix potential overflows in evergreen CS offset tracking
msm:
- DPU:
- implement DP/PHY mapping on SC8180X
- Enable writeback on SM8150, SC8180X, SM6125, SM6350
- DP:
- Enable widebus on all relevant chipsets
- MSM8998 HDMI support
- GPU:
- A642L speedbin support
- A615/A306/A621 support
- A7xx devcoredump support
ast:
- astdp: Support AST2600 with VGA
- Clean up HPD
- Fix timeout loop for DP link training
- reorganize output code by type (VGA, DP, etc)
- convert to struct drm_edid
- fix BMC handling for all outputs
exynos:
- drop stale MAINTAINERS pattern
- constify struct
loongson:
- use GEM refcount over TTM
mgag200:
- Improve BMC handling
- Support VBLANK intterupts
- transparently support BMC outputs
nouveau:
- Refactor and clean up internals
- Use GEM refcount over TTM's
gm12u320:
- convert to struct drm_edid
gma500:
- update i2c terms
lcdif:
- pixel clock fix
host1x:
- fix syncpoint IRQ during resume
- use iommu_paging_domain_alloc()
imx:
- ipuv3: convert to struct drm_edid
omapdrm:
- improve error handling
- use common helper for_each_endpoint_of_node()
panel:
- add support for BOE TV101WUM-LL2 plus DT bindings
- novatek-nt35950: improve error handling
- nv3051d: improve error handling
- panel-edp:
- add support for BOE NE140WUM-N6G
- revert support for SDC ATNA45AF01
- visionox-vtdr6130:
- improve error handling
- use devm_regulator_bulk_get_const()
- boe-th101mb31ig002:
- Support for starry-er88577 MIPI-DSI panel plus DT
- Fix porch parameter
- edp: Support AOU B116XTN02.3, AUO B116XAN06.1, AOU B116XAT04.1, BOE
NV140WUM-N41, BOE NV133WUM-N63, BOE NV116WHM-A4D, CMN N116BCA-EA2,
CMN N116BCP-EA2, CSW MNB601LS1-4
- himax-hx8394: Support Microchip AC40T08A MIPI Display panel plus DT
- ilitek-ili9806e: Support Densitron DMT028VGHMCMI-1D TFT plus DT
- jd9365da:
- Support Melfas lmfbx101117480 MIPI-DSI panel plus DT
- Refactor for code sharing
- panel-edp: fix name for HKC MB116AN01
- jd9365da: fix "exit sleep" commands
- jdi-fhd-r63452: simplify error handling with DSI multi-style
helpers
- mantix-mlaf057we51: simplify error handling with DSI multi-style
helpers
- simple:
- support Innolux G070ACE-LH3 plus DT bindings
- support On Tat Industrial Company KD50G21-40NT-A1 plus DT
bindings
- st7701:
- decouple DSI and DRM code
- add SPI support
- support Anbernic RG28XX plus DT bindings
mediatek:
- support alpha blending
- remove cl in struct cmdq_pkt
- ovl adaptor fix
- add power domain binding for mediatek DPI controller
renesas:
- rz-du: add support for RZ/G2UL plus DT bindings
rockchip:
- Improve DP sink-capability reporting
- dw_hdmi: Support 4k@60Hz
- vop:
- Support RGB display on Rockchip RK3066
- Support 4096px width
sti:
- convert to struct drm_edid
stm:
- Avoid UAF wih managed plane and CRTC helpers
- Fix module owner
- Fix error handling in probe
- Depend on COMMON_CLK
- ltdc:
- Fix transparency after disabling plane
- Remove unused interrupt
tegra:
- gr3d: improve PM domain handling
- convert to struct drm_edid
- Call drm_atomic_helper_shutdown()
vc4:
- fix PM during detect
- replace DRM_ERROR() with drm_error()
- v3d: simplify clock retrieval
v3d:
- Clean up perfmon
virtio:
- add DRM capset"
* tag 'drm-next-2024-09-19' of https://gitlab.freedesktop.org/drm/kernel: (1326 commits)
drm/xe: Fix missing conversion to xe_display_pm_runtime_resume
drm/xe/xe2hpg: Add Wa_15016589081
drm/xe: Don't keep stale pointer to bo->ggtt_node
drm/xe: fix missing 'xe_vm_put'
drm/xe: fix build warning with CONFIG_PM=n
drm/xe: Suppress missing outer rpm protection warning
drm/xe: prevent potential UAF in pf_provision_vf_ggtt()
drm/amd/display: Add all planes on CRTC to state for overlay cursor
drm/i915/bios: fix printk format width
drm/i915/display: Fix BMG CCS modifiers
drm/amdgpu: get rid of bogus includes of fdtable.h
drm/amdkfd: CRIU fixes
drm/amdgpu: fix a race in kfd_mem_export_dmabuf()
drm: new helper: drm_gem_prime_handle_to_dmabuf()
drm/amdgpu/atomfirmware: Silence UBSAN warning
drm/amdgpu: Fix kdoc entry in 'amdgpu_vm_cpu_prepare'
drm/amd/amdgpu: apply command submission parser for JPEG v1
drm/amd/amdgpu: apply command submission parser for JPEG v2+
drm/amd/pm: fix the pp_dpm_pcie issue on smu v14.0.2/3
drm/amd/pm: update the features set on smu v14.0.2/3
...
Pull powerpc updates from Michael Ellerman:
- Reduce alignment constraints on STRICT_KERNEL_RWX and speed-up TLB
misses on 8xx and 603
- Replace kretprobe code with rethook and enable fprobe
- Remove the "fast endian switch" syscall
- Handle DLPAR device tree updates in kernel, allowing the deprecation
of the binary /proc/powerpc/ofdt interface
Thanks to Abhishek Dubey, Alex Shi, Benjamin Gray, Christophe Leroy,
Gaosheng Cui, Gautam Menghani, Geert Uytterhoeven, Haren Myneni, Hari
Bathini, Huang Xiaojia, Jinjie Ruan, Madhavan Srinivasan, Miguel Ojeda,
Mina Almasry, Narayana Murty N, Naveen Rao, Rob Herring (Arm), Scott
Cheloha, Segher Boessenkool, Stephen Rothwell, Thomas Zimmermann, Uwe
Kleine-König, Vaibhav Jain, and Zhang Zekun.
* tag 'powerpc-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (59 commits)
powerpc/atomic: Use YZ constraints for DS-form instructions
MAINTAINERS: powerpc: Add Maddy
powerpc: Switch back to struct platform_driver::remove()
powerpc/pseries/eeh: Fix pseries_eeh_err_inject
selftests/powerpc: Allow building without static libc
macintosh/via-pmu: register_pmu_pm_ops() can be __init
powerpc: Stop using no_llseek
powerpc/64s: Remove the "fast endian switch" syscall
powerpc/mm/64s: Restrict THP to Radix or HPT w/64K pages
powerpc/mm/64s: Move THP reqs into a separate symbol
powerpc/64s: Make mmu_hash_ops __ro_after_init
powerpc: Replace kretprobe code with rethook on powerpc
powerpc: pseries: Constify struct kobj_type
powerpc: powernv: Constify struct kobj_type
powerpc: Constify struct kobj_type
powerpc/pseries/dlpar: Add device tree nodes for DLPAR IO add
powerpc/pseries/dlpar: Remove device tree node for DLPAR IO remove
powerpc/pseries: Use correct data types from pseries_hp_errorlog struct
powerpc/vdso: Inconditionally use CFUNC macro
powerpc/32: Implement validation of emergency stack
...
After commit 0edb555a65 ("platform: Make platform_driver::remove()
return void") .remove() is (again) the right callback to implement for
platform drivers.
Convert all pwm drivers to use .remove(), with the eventual goal to drop
struct platform_driver::remove_new(). As .remove() and .remove_new() have
the same prototypes, conversion is done by just changing the structure
member name in the driver initializer.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240909130902.851274-2-u.kleine-koenig@baylibre.com
VFIO_EEH_PE_INJECT_ERR ioctl is currently failing on pseries
due to missing implementation of err_inject eeh_ops for pseries.
This patch implements pseries_eeh_err_inject in eeh_ops/pseries
eeh_ops. Implements support for injecting MMIO load/store error
for testing from user space.
The check on PCI error type (bus type) code is moved to platform
code, since the eeh_pe_inject_err can be allowed to more error
types depending on platform requirement. Removal of the check for
'type' in eeh_pe_inject_err() doesn't impact PowerNV as
pnv_eeh_err_inject() already has an equivalent check in place.
Signed-off-by: Narayana Murty N <nnmlinux@linux.ibm.com>
Reviewed-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240909140220.529333-1-nnmlinux@linux.ibm.com
Since commit 868941b144 ("fs: remove no_llseek"), no_llseek() is
simply defined to be NULL, and a NULL llseek means seeking is
unsupported.
So for statically defined file_operations, such as all these, there's no
need or benefit to set llseek = no_llseek.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240903111951.141376-1-mpe@ellerman.id.au
Transparent hugepages (THP) are not supported when using the Hash Page
Table (HPT) MMU with 4K pages.
Currently a HPT-only 4K kernel still allows THP to be enabled, which
is misleading.
Add restrictions to the PPC_THP symbol so that if the kernel is
configured with 4K pages and only the HPT MMU (no Radix), then THP is
disabled.
Note that it's still possible to build a combined Radix/HPT kernel with 4K
pages, which does allow THP to be enabled at build time. As such the HPT
code still needs to provide some THP related symbols, to allow the build
to succeed, but those code paths are never run. See the stubs in
arch/powerpc/include/asm/book3s/64/hash-4k.h.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240823032911.1238471-2-mpe@ellerman.id.au
Move the Kconfig symbols related to transparent hugepages (THP) under a
separate config symbol, separate from CONFIG_PPC_BOOK3S_64.
The new symbol is automatically enabled if CONFIG_PPC_BOOK3S_64 is
enabled, so there is no behaviour change, except for the existence of
the new PPC_THP symbol.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240823032911.1238471-1-mpe@ellerman.id.au
'struct kobj_type' is not modified. It is only used in kobject_init()
which takes a 'const struct kobj_type *ktype' parameter.
Constifying this structure moves some data to a read-only section,
so increase over all security.
On a x86_64, compiled with ppc64 defconfig:
Before:
======
text data bss dec hex filename
1885 368 16 2269 8dd arch/powerpc/platforms/pseries/vas-sysfs.o
After:
======
text data bss dec hex filename
1981 272 16 2269 8dd arch/powerpc/platforms/pseries/vas-sysfs.o
Signed-off-by: Huang Xiaojia <huangxiaojia2@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240826150957.3500237-3-huangxiaojia2@huawei.com
'struct kobj_type' is not modified. It is only used in kobject_init()
which takes a 'const struct kobj_type *ktype' parameter.
Constifying this structure moves some data to a read-only section,
so increase over all security.
On a x86_64, compiled with ppc64 defconfig:
Before:
======
text data bss dec hex filename
3775 256 8 4039 fc7 arch/powerpc/platforms/powernv/opal-dump.o
2679 260 8 2947 b83 arch/powerpc/platforms/powernv/opal-elog.o
After:
======
text data bss dec hex filename
3823 208 8 4039 fc7 arch/powerpc/platforms/powernv/opal-dump.o
2727 212 8 2947 b83 arch/powerpc/platforms/powernv/opal-elog.o
Signed-off-by: Huang Xiaojia <huangxiaojia2@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240826150957.3500237-2-huangxiaojia2@huawei.com
In the powerpc-pseries specific implementation, the IO hotplug
event is handled in the user space (drmgr tool). For the DLPAR
IO ADD, the corresponding device tree nodes and properties will
be added to the device tree after the device enable. The user
space (drmgr tool) uses configure_connector RTAS call with the
DRC index to retrieve the device nodes and updates the device
tree by writing to /proc/ppc64/ofdt. Under system lockdown,
/dev/mem access to allocate buffers for configure_connector RTAS
call is restricted which means the user space can not issue this
RTAS call and also can not access to /proc/ppc64/ofdt. The
pseries implementation need user interaction to power-on and add
device to the slot during the ADD event handling. So adds
complexity if the complete hotplug ADD event handling moved to
the kernel.
To overcome /dev/mem access restriction, this patch extends the
/sys/kernel/dlpar interface and provides ‘dt add index <drc_index>’
to the user space. The drmgr tool uses this interface to update
the device tree whenever the device is added. This interface
retrieves device tree nodes for the corresponding DRC index using
the configure_connector RTAS call and adds new device nodes /
properties to the device tree.
Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240822025028.938332-3-haren@linux.ibm.com
In the powerpc-pseries specific implementation, the IO hotplug
event is handled in the user space (drmgr tool). But update the
device tree and /dev/mem access to allocate buffers for some
RTAS calls are restricted when the kernel lockdown feature is
enabled. For the DLPAR IO REMOVE, the corresponding device tree
nodes and properties have to be removed from the device tree
after the device disable. The user space removes the device tree
nodes by updating /proc/ppc64/ofdt which is not allowed under
system lockdown is enabled. This restriction can be resolved
by moving the complete IO hotplug handling in the kernel. But
the pseries implementation need user interaction to power off
and to remove device from the slot during hotplug event handling.
To overcome the /proc/ppc64/ofdt restriction, this patch extends
the /sys/kernel/dlpar interface and provides
‘dt remove index <drc_index>’ to the user space so that drmgr
tool can remove the corresponding device tree nodes based on DRC
index from the device tree.
Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240822025028.938332-2-haren@linux.ibm.com
_be32 type is defined for some elements in pseries_hp_errorlog
struct but also used them u32 after be32_to_cpu() conversion.
Example: In handle_dlpar_errorlog()
hp_elog->_drc_u.drc_index = be32_to_cpu(hp_elog->_drc_u.drc_index);
And later assigned to u32 type
dlpar_cpu() - u32 drc_index = hp_elog->_drc_u.drc_index;
This incorrect usage is giving the following warnings and the
patch resolve these warnings with the correct assignment.
arch/powerpc/platforms/pseries/dlpar.c:398:53: sparse: sparse:
incorrect type in argument 1 (different base types) @@
expected unsigned int [usertype] drc_index @@
got restricted __be32 [usertype] drc_index @@
...
arch/powerpc/platforms/pseries/dlpar.c:418:43: sparse: sparse:
incorrect type in assignment (different base types) @@
expected restricted __be32 [usertype] drc_count @@
got unsigned int [usertype] @@
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202408182142.wuIKqYae-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202408182302.o7QRO45S-lkp@intel.com/
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
v3:
- Fix warnings from using incorrect data types in pseries_hp_errorlog
struct
v2:
- Remove pr_info() and TODO comments
- Update more information in the commit logs
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240822025028.938332-1-haren@linux.ibm.com
This reverts commit bccc58986a.
When STRICT_KERNEL_RWX is selected, EXEC memory must stop where
RW memory start. When pinning iTLBs it means an 8M alignment for
RW data start. That may be acceptable on boards with a lot of
memory but one of my supported boards only has 32 Mbytes and this
forced alignment leads to a waste of almost 4 Mbytes with is more
than 10% of the total memory.
So revert commit bccc58986a ("powerpc/8xx: Always pin kernel text
TLB") but don't restore previous behaviour in ITLB miss handler
as now kernel PGD entries are copied into each process PGDIR.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/01b6780b860c8043b51a1ba9d83acfc6f2dde910.1724173828.git.christophe.leroy@csgroup.eu
These changes are for patch_instruction() uses on data. Unlike ppc64
these should not be incorrect as-is, but using the patch_uint() alias
better reflects what kind of data being patched and allows for
benchmarking the effect of different patch_* implementations (e.g.,
skipping instruction flushing when patching data).
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Tested-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Naveen N Rao <naveen@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240515024445.236364-5-bgray@linux.ibm.com
For any changes of struct fd representation we need to
turn existing accesses to fields into calls of wrappers.
Accesses to struct fd::flags are very few (3 in linux/file.h,
1 in net/socket.c, 3 in fs/overlayfs/file.c and 3 more in
explicit initializers).
Those can be dealt with in the commit converting to
new layout; accesses to struct fd::file are too many for that.
This commit converts (almost) all of f.file to
fd_file(f). It's not entirely mechanical ('file' is used as
a member name more than just in struct fd) and it does not
even attempt to distinguish the uses in pointer context from
those in boolean context; the latter will be eventually turned
into a separate helper (fd_empty()).
NOTE: mass conversion to fd_empty(), tempting as it
might be, is a bad idea; better do that piecewise in commit
that convert from fdget...() to CLASS(...).
[conflicts in fs/fhandle.c, kernel/bpf/syscall.c, mm/memcontrol.c
caught by git; fs/stat.c one got caught by git grep]
[fs/xattr.c conflict]
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Use of_property_present() to test for property presence rather than
of_get_property(). This is part of a larger effort to remove callers
of of_get_property() and similar functions. of_get_property() leaks
the DT property data pointer which is a problem for dynamically
allocated nodes which may be freed.
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240731191312.1710417-9-robh@kernel.org
Pull driver core updates from Greg KH:
"Here is the big set of driver core changes for 6.11-rc1.
Lots of stuff in here, with not a huge diffstat, but apis are evolving
which required lots of files to be touched. Highlights of the changes
in here are:
- platform remove callback api final fixups (Uwe took many releases
to get here, finally!)
- Rust bindings for basic firmware apis and initial driver-core
interactions.
It's not all that useful for a "write a whole driver in rust" type
of thing, but the firmware bindings do help out the phy rust
drivers, and the driver core bindings give a solid base on which
others can start their work.
There is still a long way to go here before we have a multitude of
rust drivers being added, but it's a great first step.
- driver core const api changes.
This reached across all bus types, and there are some fix-ups for
some not-common bus types that linux-next and 0-day testing shook
out.
This work is being done to help make the rust bindings more safe,
as well as the C code, moving toward the end-goal of allowing us to
put driver structures into read-only memory. We aren't there yet,
but are getting closer.
- minor devres cleanups and fixes found by code inspection
- arch_topology minor changes
- other minor driver core cleanups
All of these have been in linux-next for a very long time with no
reported problems"
* tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
ARM: sa1100: make match function take a const pointer
sysfs/cpu: Make crash_hotplug attribute world-readable
dio: Have dio_bus_match() callback take a const *
zorro: make match function take a const pointer
driver core: module: make module_[add|remove]_driver take a const *
driver core: make driver_find_device() take a const *
driver core: make driver_[create|remove]_file take a const *
firmware_loader: fix soundness issue in `request_internal`
firmware_loader: annotate doctests as `no_run`
devres: Correct code style for functions that return a pointer type
devres: Initialize an uninitialized struct member
devres: Fix memory leakage caused by driver API devm_free_percpu()
devres: Fix devm_krealloc() wasting memory
driver core: platform: Switch to use kmemdup_array()
driver core: have match() callback in struct bus_type take a const *
MAINTAINERS: add Rust device abstractions to DRIVER CORE
device: rust: improve safety comments
MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer
MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER
firmware: rust: improve safety comments
...
Pull powerpc updates from Michael Ellerman:
- Remove support for 40x CPUs & platforms
- Add support to the 64-bit BPF JIT for cpu v4 instructions
- Fix PCI hotplug driver crash on powernv
- Fix doorbell emulation for KVM on PAPR guests (nestedv2)
- Fix KVM nested guest handling of some less used SPRs
- Online NUMA nodes with no CPU/memory if they have a PCI device
attached
- Reduce memory overhead of enabling kfence on 64-bit Radix MMU kernels
- Reimplement the iommu table_group_ops for pseries for VFIO SPAPR TCE
Thanks to: Anjali K, Artem Savkov, Athira Rajeev, Breno Leitao, Brian
King, Celeste Liu, Christophe Leroy, Esben Haabendal, Gaurav Batra,
Gautam Menghani, Haren Myneni, Hari Bathini, Jeff Johnson, Krishna
Kumar, Krzysztof Kozlowski, Nathan Lynch, Nicholas Piggin, Nick Bowler,
Nilay Shroff, Rob Herring (Arm), Shawn Anastasio, Shivaprasad G Bhat,
Sourabh Jain, Srikar Dronamraju, Timothy Pearson, Uwe Kleine-König, and
Vaibhav Jain.
* tag 'powerpc-6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (57 commits)
Documentation/powerpc: Mention 40x is removed
powerpc: Remove 40x leftovers
macintosh/therm_windtunnel: fix module unload.
powerpc: Check only single values are passed to CPU/MMU feature checks
powerpc/xmon: Fix disassembly CPU feature checks
powerpc: Drop clang workaround for builtin constant checks
powerpc64/bpf: jit support for signed division and modulo
powerpc64/bpf: jit support for sign extended mov
powerpc64/bpf: jit support for sign extended load
powerpc64/bpf: jit support for unconditional byte swap
powerpc64/bpf: jit support for 32bit offset jmp instruction
powerpc/pci: Hotplug driver bridge support
pci/hotplug/pnv_php: Fix hotplug driver crash on Powernv
powerpc/configs: Update defconfig with now user-visible CONFIG_FSL_IFC
powerpc: add missing MODULE_DESCRIPTION() macros
macintosh/mac_hid: add MODULE_DESCRIPTION()
KVM: PPC: add missing MODULE_DESCRIPTION() macros
powerpc/kexec: Use of_property_read_reg()
powerpc/64s/radix/kfence: map __kfence_pool at page granularity
powerpc/pseries/iommu: Define spapr_tce_table_group_ops only with CONFIG_IOMMU_API
...
kmsg_dump doesn't forward the panic reason string to the kmsg_dumper
callback.
This patch adds a new struct kmsg_dump_detail, that will hold the
reason and description, and pass it to the dump() callback.
To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc()
function and a macro for backward compatibility.
I've written this for drm_panic, but it can be useful for other
kmsg_dumper.
It allows to see the panic reason, like "sysrq triggered crash"
or "VFS: Unable to mount root fs on xxxx" on the drm panic screen.
v2:
* Use a struct kmsg_dump_detail to hold the reason and description
pointer, for more flexibility if we want to add other parameters.
(Kees Cook)
* Fix powerpc/nvram_64 build, as I didn't update the forward
declaration of oops_to_nvram()
Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Acked-by: Petr Mladek <pmladek@suse.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Kees Cook <kees@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240702122639.248110-1-jfalempe@redhat.com
With ARCH=powerpc, make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/powerpc/kernel/rtas_flash.o
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/powerpc/sysdev/rtc_cmos_setup.o
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/powerpc/platforms/pseries/papr_scm.o
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/powerpc/platforms/cell/spufs/spufs.o
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/powerpc/platforms/cell/cbe_thermal.o
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/powerpc/platforms/cell/cpufreq_spudemand.o
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/powerpc/platforms/cell/cbe_powerbutton.o
Add the missing invocation of the MODULE_DESCRIPTION() macro to all
files which have a MODULE_LICENSE().
This includes 85xx/t1042rdb_diu.c and chrp/nvram.c which, although
they did not produce a warning with the powerpc allmodconfig
configuration, may cause this warning with other configurations.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240615-md-powerpc-arch-powerpc-v1-1-ba4956bea47a@quicinc.com
In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *. This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.
Because the match() callback is in all busses, all busses are modified
to handle this properly. This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.
For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.
Cc: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Alex Elder <elder@kernel.org>
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace 4xx usage with 44x, and replace 4xx_SOC with 44x.
Also, as pointed out by Christophe, if 44x || BOOKE can be simplified to
just test BOOKE, because 44x always selects BOOKE.
Retain the CONFIG_4xx symbol, as there are drivers that use it to mean
4xx || 44x, those will need updating before CONFIG_4xx can be removed.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240628121201.130802-6-mpe@ellerman.id.au
kexec on pseries disables AIL (reloc_on_exc), required for scv
instruction support, before other CPUs have been shut down. This means
they can execute scv instructions after AIL is disabled, which causes an
interrupt at an unexpected entry location that crashes the kernel.
Change the kexec sequence to disable AIL after other CPUs have been
brought down.
As a refresher, the real-mode scv interrupt vector is 0x17000, and the
fixed-location head code probably couldn't easily deal with implementing
such high addresses so it was just decided not to support that interrupt
at all.
Fixes: 7fa95f9ada ("powerpc/64s: system call support for scv/rfscv instructions")
Cc: stable@vger.kernel.org # v5.9+
Reported-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Closes: https://lore.kernel.org/3b4b2943-49ad-4619-b195-bc416f1d1409@linux.ibm.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Gautam Menghani <gautam@linux.ibm.com>
Tested-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Link: https://msgid.link/20240625134047.298759-1-npiggin@gmail.com
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
PPC64 IOMMU API defines iommu_table_group_ops which handles DMA
windows for PEs, their ownership transfer, create/set/unset the TCE
tables for the Dynamic DMA wundows(DDW). VFIOS uses these APIs for
support on POWER.
The commit 9d67c94335 ("powerpc/iommu: Add "borrowing"
iommu_table_group_ops") implemented partial support for this API with
"borrow" mechanism wherein the DMA windows if created already by the
host driver, they would be available for VFIO to use. Also, it didn't
have the support to control/modify the window size or the IO page
size.
The current patch implements all the necessary iommu_table_group_ops
APIs there by avoiding the "borrrowing". So, just the way it is on the
PowerNV platform, with this patch the iommu table group ownership is
transferred to the VFIO PPC subdriver, the iommu table, DMA windows
creation/deletion all driven through the APIs.
The pSeries uses the query-pe-dma-window, create-pe-dma-window and
reset-pe-dma-window RTAS calls for DMA window creation, deletion and
reset to defaul. The RTAs calls do show some minor differences to the
way things are to be handled on the pSeries which are listed below.
* On pSeries, the default DMA window size is "fixed" cannot be custom
sized as requested by the user. For non-SRIOV VFs, It is fixed at 2GB
and for SRIOV VFs, its variable sized based on the capacity assigned
to it during the VF assignment to the LPAR. So, for the default DMA
window alone the size if requested less than tce32_size, the smaller
size is enforced using the iommu table->it_size.
* The DMA start address for 32-bit window is 0, and for the 64-bit
window in case of PowerNV is hardcoded to TVE select (bit 59) at 512PiB
offset. This address is returned at the time of create_table() API call
(even before the window is created), the subsequent set_window() call
actually opens the DMA window. On pSeries, the DMA start address for
32-bit window is known from the 'ibm,dma-window' DT property. However,
the 64-bit window start address is not known until the create-pe-dma
RTAS call is made. So, the create_table() which returns the DMA window
start address actually opens the DMA window and returns the DMA start
address as returned by the Hypervisor for the create-pe-dma RTAS call.
* The reset-pe-dma RTAS call resets the DMA windows and restores the
default DMA window, however it does not clear the TCE table entries
if there are any. In case of ownership transfer from platform domain
which used direct mapping, the patch chooses remove-pe-dma instead of
reset-pe for the 64-bit window intentionally so that the
clear_dma_window() is called.
Other than the DMA window management changes mentioned above, the
patch also brings back the userspace view for the single level TCE
as it existed before commit 090bad39b2 ("powerpc/powernv: Add
indirect levels to it_userspace") along with the relavent
refactoring.
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/171923275958.1397.907964437142542242.stgit@linux.ibm.com
This patch basically brings consistency with PowerNV approach
to use the first freely available iommu table when the default
window is removed.
The pSeries iommu code convention has been that the table[0] is
for the default 32 bit DMA window and the table[1] is for the
64 bit DDW.
With VFs having only 1 DMA window, the default has to be removed
for creating the larger DMA window. The existing code uses the
table[1] for that, while marking the table[0] as NULL. This is
fine as long as the host driver itself uses the device.
For the VFIO user, on pSeries there is no way to skip table[0]
as the VFIO subdriver uses the first freely available table.
The window 0, when created as 64-bit DDW in that context would
still be on table[0], as the maximum number of windows is 1.
This won't have any impact for the host driver as the table is
fetched from the device's iommu_table_base.
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
[mpe: Rebase and resolve conflicts]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/171923272328.1397.1817843961216868850.stgit@linux.ibm.com
The ioctl VFIO_IOMMU_SPAPR_TCE_GET_INFO is not reporting the
actuals on the platform as not all the details are correctly
collected during the platform probe/scan into the iommu_table_group.
Collect the information during the device setup time as the DMA
window property is already looked up on parent nodes anyway.
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/171923271138.1397.7908302630061814623.stgit@linux.ibm.com
The PowerNV specific table_group_ops are defined in powernv/pci-ioda.c.
The pSeries specific table_group_ops are sitting in the generic powerpc
file. Move it to where it actually belong(pseries/iommu.c).
The functions are currently defined even for CONFIG_PPC_POWERNV
which are unused on PowerNV.
Only code movement, no functional changes intended.
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/171923269701.1397.15758640002786937132.stgit@linux.ibm.com
VAS allocate, modify and deallocate HCALLs returns
H_LONG_BUSY_ORDER_1_MSEC or H_LONG_BUSY_ORDER_10_MSEC for busy
delay and expects OS to reissue HCALL after that delay. But using
msleep() will often sleep at least 20 msecs even though the
hypervisor suggests OS reissue these HCALLs after 1 or 10msecs.
The open and close VAS window functions hold mutex and then issue
these HCALLs. So these operations can take longer than the
necessary when multiple threads issue open or close window APIs
simultaneously, especially might affect the performance in the
case of repeat open/close APIs for each compression request.
Multiple tasks can open / close VAS windows at the same time
which depends on the available VAS credits. For example, 240
cores system provides 4800 VAS credits. It means 4800 tasks can
execute open VAS windows HCALLs with the mutex. Since each
msleep() will often sleep more than 20 msecs, some tasks are
waiting more than 120 secs to acquire mutex. It can cause hung
traces for these tasks in dmesg due to mutex contention around
open/close HCALLs.
Instead of msleep(), use usleep_range() to ensure sleep with
the expected value before issuing HCALL again. So since each
task sleep 10 msecs maximum, this patch allow more tasks can
issue open/close VAS calls without any hung traces in the
dmesg.
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Suggested-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240116055910.421605-1-haren@linux.ibm.com
In the current design, a numa-node is made online only if that node is
attached to cpu/memory. With this design, if any PCI/IO device is found
to be attached to a numa-node which is not online then the numa-node
id of the corresponding PCI/IO device is set to NUMA_NO_NODE(-1). This
design may negatively impact the performance of PCIe device if the
numa-node assigned to PCIe device is -1 because in such case we may not
be able to accurately calculate the distance between two nodes.
The multi-controller NVMe PCIe disk has an issue with calculating the
node distance if the PCIe NVMe controller is attached to a PCI host
bridge which has numa-node id value set to NUMA_NO_NODE. This patch
helps fix this ensuring that a cpu/memory less numa node is made online
if it's attached to PCI host bridge.
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240517142531.3273464-3-nilay@linux.ibm.com
Dynamic DMA Window (DDW) supports TCEs that are backed by 2MB page
size. In most configurations, DDW is big enough to pre-map all of LPAR
memory for IO. Pre-mapping of memory for DMA results in improvements in
IO performance.
Persistent memory, vPMEM, can be assigned to an LPAR as well. vPMEM is
not contiguous with LPAR memory and usually is assigned at high memory
addresses. This makes is not possible to pre-map both vPMEM and LPAR
memory in the same DDW.
For a dedicated adapter this limitation is not an issue. Dedicated
adapters can have both Default DMA window, which is backed by 4K page
size and a DDW backed by 2MB page size TCEs. In this scenario, LPAR
memory is pre-mapped in the DDW. Any DMA going to the vPMEM is routed
via dynamically allocated TCEs in the default window.
The issue arises with SR-IOV adapters. There is only one DMA window -
either Default or DDW. If an LPAR has vPMEM assigned, memory is not
pre-mapped in the DDW since TCEs needs to be allocated for vPMEM as well.
In this case, DDW is created and TCEs are dynamically allocated for both
vPMEM and LPAR memory.
Today, DDW is only used in single mode - direct mapped TCEs or
dynamically mapped TCEs. This enhancement breaks a single DDW in 2
regions -
1. First region to pre-map LPAR memory
2. Second region to dynamically allocate TCEs for IO to vPMEM
The DDW is split only if it is big enough to pre-map complete LPAR
memory and still have some space left to dynamically map vPMEM. Maximum
size possible DDW is created as permitted by the Hypervisor.
Signed-off-by: Gaurav Batra <gbatra@linux.ibm.com>
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240514014608.35537-1-gbatra@linux.ibm.com
