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2022-11-09drm/nouveau/nvkm: add locking to subdev/engine init pathsBen Skeggs4-69/+142
This wasn't really needed before; the main place this could race is with channel recovery, but (through potentially fragile means) shouldn't have been possible. However, a number of upcoming patches benefit from having better control over subdev init, necessitating some improvements here. - allows subdev/engine oneinit() without init() (host/fifo patches) - merges engine use locking/tracking into subdev, and extends it to fix some issues that will arise with future usage patterns (acr patches) Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/mc/ga100: switch to using NV_PMC_DEVICE_ENABLEBen Skeggs1-3/+44
- NV_PMC_ENABLE still exists, but we don't touch anything in it yet Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/mc: move NV_PMC_ENABLE bashing to chipset-specific codeBen Skeggs16-11/+56
Ampere needs different handling here, most of what we touch has moved. We probably want to refactor these interfaces in general, but I'm not yet sure how they should look, this will get the job done for now. Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/mc: implement intr handling on top of nvkm_intrBen Skeggs21-577/+285
- new-style handlers can now be used here too - decent clean-up Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/fault/ga100: initial supportBen Skeggs1-0/+6
TU102 implementation should be OK for Ampere now. v2. fixup for ga103 early merge Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
2022-11-09drm/nouveau/fault/tu102: switch to explicit intr handlersBen Skeggs4-72/+52
- reads vectors from HW, rather than being hardcoded - removes hacks to support routing via old interfaces Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/vfn/tu102-: support new-style interrupt treeBen Skeggs6-15/+99
- switches ampere over now, and removes its hack mc implementation Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/vfn: move NV_USERMODE class from hostBen Skeggs17-92/+67
- uses proper class IDs for Turing/Ampere Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/vfn: add stub subdev for dev_funcBen Skeggs11-0/+197
Initially for NV_USERMODE class, and Turing/Ampere's new interrupt tree. v2. fixup for ga103 early merge Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
2022-11-09drm/nouveau/intr: add nvkm_subdev_intr() compatibilityBen Skeggs4-0/+65
It's quite a lot of tedious and error-prone work to switch over all the subdevs at once, so allow an nvkm_intr to request new-style handlers to be created that wrap the existing interfaces. This will allow a more gradual transition. Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/intr: support multiple trees, and explicit interfacesBen Skeggs3-2/+344
Turing adds a second top-level interrupt tree in HW, in addition to the trees available via NV_PMC. Most of the interrupts we care about are exposed in both trees, but not all of them, and we have some rather nasty hacks to route the fault buffer interrupts. Ampere removes the NV_PMC trees entirely. Here we add some infrastructure to be able to handle all of this more cleanly, as well as providing more explicit control over handlers. Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/intr: add shared interrupt plumbing between pci/tegraBen Skeggs10-75/+161
Unifies the handling between PCI-based and Tegra GPUs, and makes more explicit/obvious where device interrupts can be expected. Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/top: parse device topology right after devinitBen Skeggs6-10/+18
We're going to want this information available earlier than it is now. Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/nvkm: give each nvkm_event its own lockdep classBen Skeggs2-6/+19
The vblank and nonstall events have some annoying interactions with DRM locking, and aren't able to do certain things as a result. However, other uses of event notifications don't have such requirements, and upcoming patches take advantage of this for various improvements. Having separate classes for each nvkm_event's spinlocks allows lockdep to distinguish between them and avoid false-positives. v2: __always_inline + comment Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/kms: switch to drm fbdev helpersBen Skeggs12-1581/+15
This removes support for accelerated fbcon rendering, and fixes a number of races/crashes/issues around suspend/resume/module unload etc. Losing HW accelerated rendering isn't ideal, but it's been significantly reduced in performance since the removal of accelerated scrolling in the kernel anyway - not to mention, can be racey (skips cpu<->gpu sync) from certain contexts. Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
2022-11-09drm/nouveau/nvkm: rip out old notifyBen Skeggs25-805/+33
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/fifo: expose channel killed in host channel event classBen Skeggs15-66/+30
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/fifo: expose non-stall intr in host channel event classBen Skeggs14-70/+64
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: expose page flip event classBen Skeggs7-51/+42
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: expose conn event classBen Skeggs21-269/+187
This removes some now-unnecessary nesting of workqueues. v2: - use ?: (lyude) Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: expose head event classBen Skeggs11-71/+62
Also fixes vblank interrupts being left enabled when they're not meant to be as a result of races/bugs in previous event handling code. v2: - use ?: (lyude) Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: switch vblank semaphore release to nvkm_event_ntfyBen Skeggs6-35/+19
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/fault: expose replayable fault buffer event classBen Skeggs4-48/+53
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/fault: switch non-replayable faults to nvkm_event_ntfyBen Skeggs6-24/+44
v2: fix flush_work() being called uninitialised during init Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/nvkm: add a replacement for nvkm_notifyBen Skeggs21-29/+547
This replaces the twisty, confusing, relationship between nvkm_event and nvkm_notify with something much simpler, and less racey. It also places events in the object tree hierarchy, which will allow a heap of the code tracking events across allocation/teardown/suspend to be removed. This commit just adds the new interfaces, and passes the owning subdev to the event constructor to enable debug-tracing in the new code. v2: - use ?: (lyude) Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: move head scanoutpos methodBen Skeggs13-269/+71
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: add head classBen Skeggs16-3/+175
v2: remove extra whitespace Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: move DP MST payload config methodBen Skeggs7-79/+57
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: add method to trigger DP link retrainBen Skeggs8-62/+124
This moves control of link retraining in response to HPD IRQ to the KMS driver's HPD IRQ handler. NVKM still handles checking link status for the moment, this can be moved to the KMS driver when it takes explicit control of link rate selection. v2: - skip source config on retrain (fixes some retrain failures) Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/kms: pass event mask to hpd handlerBen Skeggs4-17/+29
Will be moving the DP link status check / re-train here so it's safe from racing with modeset routing changes. MST message handling etc. will remain where it is. Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/kms: switch hpd_lock from mutex to spinlockBen Skeggs3-10/+10
There's no good reason for this to be a mutex, and once the layers of workqueues have been untangled, nouveau_connector_hpd() can be called from IRQ context and won't be able to take a mutex. Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: add method to control DPAUX pad powerBen Skeggs8-51/+93
This removes the need for NVKM to track DP HPD events, as the KMS driver follows them already, and has better information available. Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: move DP link config into acquireBen Skeggs9-60/+65
Aside from fixing MST->SST switching (KMS never turned off MST link config), this should preserve existing behaviour for the moment, but provide a path for the KMS driver to have more explicit control of the DP link, which has been requested by Lyude. More research into modeset/supervisor interactions is needed before we can have fully explicit control from the KMS driver. Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: move HDA ELD methodBen Skeggs7-71/+81
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-09drm/nouveau/disp: move HDMI config into acquire + infoframe methodsBen Skeggs21-378/+503
v2: - fix typo in sorhdmi/g84 struct initialiser (kbuild test robot) v3: - less convoluted flow control in nvkm_uoutp_mthd_acquire_tmds() (lyude) v4: - we don't support hdmi on original nv50, don't try Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-07drm/nouveau/disp: move LVDS protocol information into acquireBen Skeggs10-61/+50
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-07drm/nouveau/disp: move and extend the role of outp acquire/release methodsBen Skeggs9-100/+213
There are various pieces of information we pass to NVKM about the next modeset, which are generally used while handling supervisor interrupts. We had to start passing in some information about audio requirements a while back to allocate an appropriate SOR in ACQUIRE, so we may as well move all this type of information here for other protocols too. Certain methods will be blocked on non-acquired outputs now, preventing NULL pointer derefs from KMS driver bugs. Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com>
2022-11-05drm/fb-helper: Rename drm_fb_helper_unregister_fbi() to use _info postfixThomas Zimmermann1-1/+1
Rename drm_fb_helper_unregister_fbi() to drm_fb_helper_unregister_info() as part of unifying the naming within fbdev helpers. Adapt drivers. No functional changes. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-15-tzimmermann@suse.de
2022-11-05drm/fb-helper: Rename drm_fb_helper_alloc_fbi() to use _info postfixThomas Zimmermann1-1/+1
Rename drm_fb_helper_alloc_fbi() to drm_fb_helper_alloc_info() as part of unifying the naming within fbdev helpers. Adapt drivers. No functional changes. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-14-tzimmermann@suse.de
2022-11-05drm/fb_helper: Rename field fbdev to info in struct drm_fb_helperThomas Zimmermann1-12/+11
Rename struct drm_fb_helper.fbdev to info. The current name is misleading as it overlaps with generic fbdev naming conventions. Adapt to the usual naming in fbdev drivers by calling the field 'info'. No functional changes. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221103151446.2638-13-tzimmermann@suse.de
2022-10-27drm/ttm: rework on ttm_resource to use size_t typeSomalapuram Amaranath11-19/+18
Change ttm_resource structure from num_pages to size_t size in bytes. v1 -> v2: change PFN_UP(dst_mem->size) to ttm->num_pages v1 -> v2: change bo->resource->size to bo->base.size at some places v1 -> v2: remove the local variable v1 -> v2: cleanup cmp_size_smaller_first() v2 -> v3: adding missing PFN_UP in ttm_bo_vm_fault_reserved Signed-off-by: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221027091237.983582-1-Amaranath.Somalapuram@amd.com Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com>
2022-10-22nouveau/dmem: Remove duplicated include in nouveau_dmem.cYang Li1-1/+0
./drivers/gpu/drm/nouveau/nouveau_dmem.c: nvif/if000c.h is included more than once. Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2404 Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Reviewed-by: Lyude Paul <lyude@redhat.com> Signed-off-by: Lyude Paul <lyude@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221017000723.113744-1-yang.lee@linux.alibaba.com
2022-10-21drm/nouveau: Remove unused variableZack Rusin1-1/+0
Trivial removal of an unused variable. Not sure how it snuck by me and build bots in the 7c99616e3fe7. Fixes: 7c99616e3fe7 ("drm: Remove drm_mode_config::fb_base") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: Thomas Zimmermann <tzimemrmann@suse.de> Cc: Christian König <christian.koenig@amd.com> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Karol Herbst <kherbst@redhat.com> Cc: Lyude Paul <lyude@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com> Signed-off-by: Zack Rusin <zackr@vmware.com> Signed-off-by: Lyude Paul <lyude@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221021010703.536318-1-zack@kde.org
2022-10-21nouveau: Fix migrate_to_ram() for faulting pageAlistair Popple1-0/+1
Commit 16ce101db85d ("mm/memory.c: fix race when faulting a device private page") changed the migrate_to_ram() callback to take a reference on the device page to ensure it can't be freed while handling the fault. Unfortunately the corresponding update to Nouveau to accommodate this change was inadvertently dropped from that patch causing GPU to CPU migration to fail so add it here. Signed-off-by: Alistair Popple <apopple@nvidia.com> Fixes: 16ce101db85d ("mm/memory.c: fix race when faulting a device private page") Cc: John Hubbard <jhubbard@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Lyude Paul <lyude@redhat.com> Cc: Ben Skeggs <bskeggs@redhat.com> Reviewed-by: Lyude Paul <lyude@redhat.com> Signed-off-by: Lyude Paul <lyude@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221019122934.866205-1-apopple@nvidia.com
2022-10-20drm: Remove drm_mode_config::fb_baseZack Rusin2-3/+4
The fb_base in struct drm_mode_config has been unused for a long time. Some drivers set it and some don't leading to a very confusing state where the variable can't be relied upon, because there's no indication as to which driver sets it and which doesn't. The only usage of fb_base is internal to two drivers so instead of trying to force it into all the drivers to get it into a coherent state completely remove it. Signed-off-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Thomas Zimmermann <tzimemrmann@suse.de> Acked-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221019024401.394617-1-zack@kde.org
2022-10-18Merge drm/drm-next into drm-misc-nextMaxime Ripard3-31/+99
Let's kick-off this release cycle. Signed-off-by: Maxime Ripard <maxime@cerno.tech>
2022-10-14Merge tag 'mm-stable-2022-10-13' of ↵Linus Torvalds1-31/+77
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull more MM updates from Andrew Morton: - fix a race which causes page refcounting errors in ZONE_DEVICE pages (Alistair Popple) - fix userfaultfd test harness instability (Peter Xu) - various other patches in MM, mainly fixes * tag 'mm-stable-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (29 commits) highmem: fix kmap_to_page() for kmap_local_page() addresses mm/page_alloc: fix incorrect PGFREE and PGALLOC for high-order page mm/selftest: uffd: explain the write missing fault check mm/hugetlb: use hugetlb_pte_stable in migration race check mm/hugetlb: fix race condition of uffd missing/minor handling zram: always expose rw_page LoongArch: update local TLB if PTE entry exists mm: use update_mmu_tlb() on the second thread kasan: fix array-bounds warnings in tests hmm-tests: add test for migrate_device_range() nouveau/dmem: evict device private memory during release nouveau/dmem: refactor nouveau_dmem_fault_copy_one() mm/migrate_device.c: add migrate_device_range() mm/migrate_device.c: refactor migrate_vma and migrate_deivce_coherent_page() mm/memremap.c: take a pgmap reference on page allocation mm: free device private pages have zero refcount mm/memory.c: fix race when faulting a device private page mm/damon: use damon_sz_region() in appropriate place mm/damon: move sz_damon_region to damon_sz_region lib/test_meminit: add checks for the allocation functions ...
2022-10-13nouveau/dmem: evict device private memory during releaseAlistair Popple1-0/+48
When the module is unloaded or a GPU is unbound from the module it is possible for device private pages to still be mapped in currently running processes. This can lead to a hangs and RCU stall warnings when unbinding the device as memunmap_pages() will wait in an uninterruptible state until all device pages have been freed which may never happen. Fix this by migrating device mappings back to normal CPU memory prior to freeing the GPU memory chunks and associated device private pages. Link: https://lkml.kernel.org/r/66277601fb8fda9af408b33da9887192bf895bda.1664366292.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Cc: Lyude Paul <lyude@redhat.com> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Alex Sierra <alex.sierra@amd.com> Cc: Christian König <christian.koenig@amd.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Felix Kuehling <Felix.Kuehling@amd.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Yang Shi <shy828301@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-13nouveau/dmem: refactor nouveau_dmem_fault_copy_one()Alistair Popple1-30/+28
nouveau_dmem_fault_copy_one() is used during handling of CPU faults via the migrate_to_ram() callback and is used to copy data from GPU to CPU memory. It is currently specific to fault handling, however a future patch implementing eviction of data during teardown needs similar functionality. Refactor out the core functionality so that it is not specific to fault handling. Link: https://lkml.kernel.org/r/20573d7b4e641a78fde9935f948e64e71c9e709e.1664366292.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Reviewed-by: Lyude Paul <lyude@redhat.com> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Alex Sierra <alex.sierra@amd.com> Cc: Christian König <christian.koenig@amd.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Felix Kuehling <Felix.Kuehling@amd.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Yang Shi <shy828301@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-13mm: free device private pages have zero refcountAlistair Popple1-1/+1
Since 27674ef6c73f ("mm: remove the extra ZONE_DEVICE struct page refcount") device private pages have no longer had an extra reference count when the page is in use. However before handing them back to the owning device driver we add an extra reference count such that free pages have a reference count of one. This makes it difficult to tell if a page is free or not because both free and in use pages will have a non-zero refcount. Instead we should return pages to the drivers page allocator with a zero reference count. Kernel code can then safely use kernel functions such as get_page_unless_zero(). Link: https://lkml.kernel.org/r/cf70cf6f8c0bdb8aaebdbfb0d790aea4c683c3c6.1664366292.git-series.apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Acked-by: Felix Kuehling <Felix.Kuehling@amd.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Christian König <christian.koenig@amd.com> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Lyude Paul <lyude@redhat.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Alex Sierra <alex.sierra@amd.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Yang Shi <shy828301@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
generated by cgit v1.2.3 (git 2.39.0) at 2025-09-13 07:46:43 +0300