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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
drm/xe/svm: Add xe_svm_ranges_zap_ptes_in_range() for PTE zapping
Introduce xe_svm_ranges_zap_ptes_in_range(), a function to zap page table
entries (PTEs) for all SVM ranges within a user-specified address range.
-v2 (Matthew Brost)
Lock should be called even for tlb_invalidation
v3(Matthew Brost)
- Update comment
- s/notifier->itree.start/drm_gpusvm_notifier_start
- s/notifier->itree.last + 1/drm_gpusvm_notifier_end
- use WRITE_ONCE
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://lore.kernel.org/r/20250821173104.3030148-8-himal.prasad.ghimiray@intel.com
Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
+71
-1
+13
-1
drivers/gpu/drm/xe/xe_pt.c
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-1
drivers/gpu/drm/xe/xe_pt.c
···
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struct xe_pt *pt = vm->pt_root[tile->id];
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u8 pt_mask = (range->tile_present & ~range->tile_invalidated);
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-
xe_svm_assert_in_notifier(vm);
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/*
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* Locking rules:
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*
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* - notifier_lock (write): full protection against page table changes
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* and MMU notifier invalidations.
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*
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* - notifier_lock (read) + vm_lock (write): combined protection against
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* invalidations and concurrent page table modifications. (e.g., madvise)
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*
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*/
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lockdep_assert(lockdep_is_held_type(&vm->svm.gpusvm.notifier_lock, 0) ||
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(lockdep_is_held_type(&vm->svm.gpusvm.notifier_lock, 1) &&
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lockdep_is_held_type(&vm->lock, 0)));
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if (!(pt_mask & BIT(tile->id)))
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return false;
+50
drivers/gpu/drm/xe/xe_svm.c
+50
drivers/gpu/drm/xe/xe_svm.c
···
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return err;
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}
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/**
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* xe_svm_ranges_zap_ptes_in_range - clear ptes of svm ranges in input range
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* @vm: Pointer to the xe_vm structure
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* @start: Start of the input range
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* @end: End of the input range
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*
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* This function removes the page table entries (PTEs) associated
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* with the svm ranges within the given input start and end
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*
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* Return: tile_mask for which gt's need to be tlb invalidated.
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*/
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u8 xe_svm_ranges_zap_ptes_in_range(struct xe_vm *vm, u64 start, u64 end)
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{
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struct drm_gpusvm_notifier *notifier;
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struct xe_svm_range *range;
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u64 adj_start, adj_end;
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struct xe_tile *tile;
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u8 tile_mask = 0;
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u8 id;
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+
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lockdep_assert(lockdep_is_held_type(&vm->svm.gpusvm.notifier_lock, 1) &&
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lockdep_is_held_type(&vm->lock, 0));
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+
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drm_gpusvm_for_each_notifier(notifier, &vm->svm.gpusvm, start, end) {
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struct drm_gpusvm_range *r = NULL;
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+
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adj_start = max(start, drm_gpusvm_notifier_start(notifier));
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adj_end = min(end, drm_gpusvm_notifier_end(notifier));
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drm_gpusvm_for_each_range(r, notifier, adj_start, adj_end) {
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range = to_xe_range(r);
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for_each_tile(tile, vm->xe, id) {
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if (xe_pt_zap_ptes_range(tile, vm, range)) {
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tile_mask |= BIT(id);
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/*
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* WRITE_ONCE pairs with READ_ONCE in
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* xe_vm_has_valid_gpu_mapping().
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* Must not fail after setting
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* tile_invalidated and before
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* TLB invalidation.
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*/
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WRITE_ONCE(range->tile_invalidated,
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range->tile_invalidated | BIT(id));
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}
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}
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}
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}
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return tile_mask;
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}
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#if IS_ENABLED(CONFIG_DRM_XE_PAGEMAP)
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static struct drm_pagemap *tile_local_pagemap(struct xe_tile *tile)
+8
drivers/gpu/drm/xe/xe_svm.h
+8
drivers/gpu/drm/xe/xe_svm.h
···
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void xe_svm_unmap_address_range(struct xe_vm *vm, u64 start, u64 end);
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u8 xe_svm_ranges_zap_ptes_in_range(struct xe_vm *vm, u64 start, u64 end);
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/**
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* xe_svm_range_has_dma_mapping() - SVM range has DMA mapping
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* @range: SVM range
···
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static inline
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void xe_svm_unmap_address_range(struct xe_vm *vm, u64 start, u64 end)
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{
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}
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static inline
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u8 xe_svm_ranges_zap_ptes_in_range(struct xe_vm *vm, u64 start, u64 end)
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{
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return 0;
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}
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#define xe_svm_assert_in_notifier(...) do {} while (0)