On Fri, Mar 28, 2025 at 06:10:32PM +0000, Matthew Auld wrote:
> Pull the pages stuff from the svm range into its own substructure, with
> the idea of having the main pages related routines, like get_pages(),
> unmap_pages() and free_pages() all operating on some lower level
> structures, which can then be re-used for stuff like userptr.
>
> v2:
> - Move seq into pages struct (Matt B)
>
> Suggested-by: Matthew Brost <matthew.br...@intel.com>
Reviewed-by: Matthew Brost <matthew.br...@intel.com>
> Signed-off-by: Matthew Auld <matthew.a...@intel.com>
> Cc: Thomas Hellström <thomas.hellst...@linux.intel.com>
> ---
> drivers/gpu/drm/drm_gpusvm.c | 66 ++++++++++++++++++++----------------
> drivers/gpu/drm/xe/xe_pt.c | 2 +-
> drivers/gpu/drm/xe/xe_svm.c | 8 ++---
> drivers/gpu/drm/xe/xe_svm.h | 6 ++--
> include/drm/drm_gpusvm.h | 53 +++++++++++++++++------------
> 5 files changed, 76 insertions(+), 59 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_gpusvm.c b/drivers/gpu/drm/drm_gpusvm.c
> index e0c8d450752a..c3d70403fbcc 100644
> --- a/drivers/gpu/drm/drm_gpusvm.c
> +++ b/drivers/gpu/drm/drm_gpusvm.c
> @@ -811,8 +811,8 @@ drm_gpusvm_range_alloc(struct drm_gpusvm *gpusvm,
> range->itree.start = ALIGN_DOWN(fault_addr, chunk_size);
> range->itree.last = ALIGN(fault_addr + 1, chunk_size) - 1;
> INIT_LIST_HEAD(&range->entry);
> - range->notifier_seq = LONG_MAX;
> - range->flags.migrate_devmem = migrate_devmem ? 1 : 0;
> + range->pages.notifier_seq = LONG_MAX;
> + range->pages.flags.migrate_devmem = migrate_devmem ? 1 : 0;
>
> return range;
> }
> @@ -1140,15 +1140,16 @@ static void __drm_gpusvm_range_unmap_pages(struct
> drm_gpusvm *gpusvm,
> struct drm_gpusvm_range *range,
> unsigned long npages)
> {
> - unsigned long i, j;
> - struct drm_pagemap *dpagemap = range->dpagemap;
> + struct drm_gpusvm_pages *svm_pages = &range->pages;
> + struct drm_pagemap *dpagemap = svm_pages->dpagemap;
> struct device *dev = gpusvm->drm->dev;
> + unsigned long i, j;
>
> lockdep_assert_held(&gpusvm->notifier_lock);
>
> - if (range->flags.has_dma_mapping) {
> + if (svm_pages->flags.has_dma_mapping) {
> for (i = 0, j = 0; i < npages; j++) {
> - struct drm_pagemap_device_addr *addr =
> &range->dma_addr[j];
> + struct drm_pagemap_device_addr *addr =
> &svm_pages->dma_addr[j];
>
> if (addr->proto == DRM_INTERCONNECT_SYSTEM)
> dma_unmap_page(dev,
> @@ -1160,9 +1161,9 @@ static void __drm_gpusvm_range_unmap_pages(struct
> drm_gpusvm *gpusvm,
> dev, *addr);
> i += 1 << addr->order;
> }
> - range->flags.has_devmem_pages = false;
> - range->flags.has_dma_mapping = false;
> - range->dpagemap = NULL;
> + svm_pages->flags.has_devmem_pages = false;
> + svm_pages->flags.has_dma_mapping = false;
> + svm_pages->dpagemap = NULL;
> }
> }
>
> @@ -1176,11 +1177,13 @@ static void __drm_gpusvm_range_unmap_pages(struct
> drm_gpusvm *gpusvm,
> static void drm_gpusvm_range_free_pages(struct drm_gpusvm *gpusvm,
> struct drm_gpusvm_range *range)
> {
> + struct drm_gpusvm_pages *svm_pages = &range->pages;
> +
> lockdep_assert_held(&gpusvm->notifier_lock);
>
> - if (range->dma_addr) {
> - kvfree(range->dma_addr);
> - range->dma_addr = NULL;
> + if (svm_pages->dma_addr) {
> + kvfree(svm_pages->dma_addr);
> + svm_pages->dma_addr = NULL;
> }
> }
>
> @@ -1291,9 +1294,11 @@ EXPORT_SYMBOL_GPL(drm_gpusvm_range_put);
> bool drm_gpusvm_range_pages_valid(struct drm_gpusvm *gpusvm,
> struct drm_gpusvm_range *range)
> {
> + struct drm_gpusvm_pages *svm_pages = &range->pages;
> +
> lockdep_assert_held(&gpusvm->notifier_lock);
>
> - return range->flags.has_devmem_pages || range->flags.has_dma_mapping;
> + return svm_pages->flags.has_devmem_pages ||
> svm_pages->flags.has_dma_mapping;
> }
> EXPORT_SYMBOL_GPL(drm_gpusvm_range_pages_valid);
>
> @@ -1311,9 +1316,10 @@ static bool
> drm_gpusvm_range_pages_valid_unlocked(struct drm_gpusvm *gpusvm,
> struct drm_gpusvm_range *range)
> {
> + struct drm_gpusvm_pages *svm_pages = &range->pages;
> bool pages_valid;
>
> - if (!range->dma_addr)
> + if (!svm_pages->dma_addr)
> return false;
>
> drm_gpusvm_notifier_lock(gpusvm);
> @@ -1340,6 +1346,7 @@ int drm_gpusvm_range_get_pages(struct drm_gpusvm
> *gpusvm,
> struct drm_gpusvm_range *range,
> const struct drm_gpusvm_ctx *ctx)
> {
> + struct drm_gpusvm_pages *svm_pages = &range->pages;
> struct mmu_interval_notifier *notifier = &range->notifier->notifier;
> struct hmm_range hmm_range = {
> .default_flags = HMM_PFN_REQ_FAULT | (ctx->read_only ? 0 :
> @@ -1409,7 +1416,7 @@ int drm_gpusvm_range_get_pages(struct drm_gpusvm
> *gpusvm,
> */
> drm_gpusvm_notifier_lock(gpusvm);
>
> - if (range->flags.unmapped) {
> + if (svm_pages->flags.unmapped) {
> drm_gpusvm_notifier_unlock(gpusvm);
> err = -EFAULT;
> goto err_free;
> @@ -1421,13 +1428,12 @@ int drm_gpusvm_range_get_pages(struct drm_gpusvm
> *gpusvm,
> goto retry;
> }
>
> - if (!range->dma_addr) {
> + if (!svm_pages->dma_addr) {
> /* Unlock and restart mapping to allocate memory. */
> drm_gpusvm_notifier_unlock(gpusvm);
> - range->dma_addr = kvmalloc_array(npages,
> - sizeof(*range->dma_addr),
> - GFP_KERNEL);
> - if (!range->dma_addr) {
> + svm_pages->dma_addr =
> + kvmalloc_array(npages, sizeof(*svm_pages->dma_addr),
> GFP_KERNEL);
> + if (!svm_pages->dma_addr) {
> err = -ENOMEM;
> goto err_free;
> }
> @@ -1465,13 +1471,13 @@ int drm_gpusvm_range_get_pages(struct drm_gpusvm
> *gpusvm,
> goto err_unmap;
> }
> }
> - range->dma_addr[j] =
> + svm_pages->dma_addr[j] =
> dpagemap->ops->device_map(dpagemap,
> gpusvm->drm->dev,
> page, order,
> dma_dir);
> if (dma_mapping_error(gpusvm->drm->dev,
> - range->dma_addr[j].addr)) {
> + svm_pages->dma_addr[j].addr)) {
> err = -EFAULT;
> goto err_unmap;
> }
> @@ -1494,7 +1500,7 @@ int drm_gpusvm_range_get_pages(struct drm_gpusvm
> *gpusvm,
> goto err_unmap;
> }
>
> - range->dma_addr[j] = drm_pagemap_device_addr_encode
> + svm_pages->dma_addr[j] = drm_pagemap_device_addr_encode
> (addr, DRM_INTERCONNECT_SYSTEM, order,
> dma_dir);
> }
> @@ -1502,16 +1508,16 @@ int drm_gpusvm_range_get_pages(struct drm_gpusvm
> *gpusvm,
> num_dma_mapped = i;
> }
>
> - range->flags.has_dma_mapping = true;
> + svm_pages->flags.has_dma_mapping = true;
> if (zdd) {
> - range->flags.has_devmem_pages = true;
> - range->dpagemap = dpagemap;
> + svm_pages->flags.has_devmem_pages = true;
> + svm_pages->dpagemap = dpagemap;
> }
>
> drm_gpusvm_notifier_unlock(gpusvm);
> kvfree(pfns);
> set_seqno:
> - range->notifier_seq = hmm_range.notifier_seq;
> + svm_pages->notifier_seq = hmm_range.notifier_seq;
>
> return 0;
>
> @@ -1718,7 +1724,7 @@ int drm_gpusvm_migrate_to_devmem(struct drm_gpusvm
> *gpusvm,
>
> mmap_assert_locked(gpusvm->mm);
>
> - if (!range->flags.migrate_devmem)
> + if (!range->pages.flags.migrate_devmem)
> return -EINVAL;
>
> if (!ops->populate_devmem_pfn || !ops->copy_to_devmem ||
> @@ -2247,10 +2253,10 @@ void drm_gpusvm_range_set_unmapped(struct
> drm_gpusvm_range *range,
> {
> lockdep_assert_held_write(&range->gpusvm->notifier_lock);
>
> - range->flags.unmapped = true;
> + range->pages.flags.unmapped = true;
> if (drm_gpusvm_range_start(range) < mmu_range->start ||
> drm_gpusvm_range_end(range) > mmu_range->end)
> - range->flags.partial_unmap = true;
> + range->pages.flags.partial_unmap = true;
> }
> EXPORT_SYMBOL_GPL(drm_gpusvm_range_set_unmapped);
>
> diff --git a/drivers/gpu/drm/xe/xe_pt.c b/drivers/gpu/drm/xe/xe_pt.c
> index 82ae159feed1..9ac9291baeac 100644
> --- a/drivers/gpu/drm/xe/xe_pt.c
> +++ b/drivers/gpu/drm/xe/xe_pt.c
> @@ -701,7 +701,7 @@ xe_pt_stage_bind(struct xe_tile *tile, struct xe_vma *vma,
> return -EAGAIN;
> }
> if (xe_svm_range_has_dma_mapping(range)) {
> - xe_res_first_dma(range->base.dma_addr, 0,
> + xe_res_first_dma(range->base.pages.dma_addr, 0,
> range->base.itree.last + 1 -
> range->base.itree.start,
> &curs);
> xe_svm_range_debug(range, "BIND PREPARE - MIXED");
> diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c
> index c7424c824a14..be077766fd73 100644
> --- a/drivers/gpu/drm/xe/xe_svm.c
> +++ b/drivers/gpu/drm/xe/xe_svm.c
> @@ -17,7 +17,7 @@
> static bool xe_svm_range_in_vram(struct xe_svm_range *range)
> {
> /* Not reliable without notifier lock */
> - return range->base.flags.has_devmem_pages;
> + return range->base.pages.flags.has_devmem_pages;
> }
>
> static bool xe_svm_range_has_vram_binding(struct xe_svm_range *range)
> @@ -59,7 +59,7 @@ static unsigned long xe_svm_range_size(struct xe_svm_range
> *range)
> (r__)->base.gpusvm, \
> xe_svm_range_in_vram((r__)) ? 1 : 0, \
> xe_svm_range_has_vram_binding((r__)) ? 1 : 0, \
> - (r__)->base.notifier_seq, \
> + (r__)->base.pages.notifier_seq, \
> xe_svm_range_start((r__)), xe_svm_range_end((r__)), \
> xe_svm_range_size((r__)))
>
> @@ -135,7 +135,7 @@ xe_svm_range_notifier_event_begin(struct xe_vm *vm,
> struct drm_gpusvm_range *r,
> range_debug(range, "NOTIFIER");
>
> /* Skip if already unmapped or if no binding exist */
> - if (range->base.flags.unmapped || !range->tile_present)
> + if (range->base.pages.flags.unmapped || !range->tile_present)
> return 0;
>
> range_debug(range, "NOTIFIER - EXECUTE");
> @@ -783,7 +783,7 @@ int xe_svm_handle_pagefault(struct xe_vm *vm, struct
> xe_vma *vma,
> range_debug(range, "PAGE FAULT");
>
> /* XXX: Add migration policy, for now migrate range once */
> - if (!range->skip_migrate && range->base.flags.migrate_devmem &&
> + if (!range->skip_migrate && range->base.pages.flags.migrate_devmem &&
> xe_svm_range_size(range) >= SZ_64K) {
> range->skip_migrate = true;
>
> diff --git a/drivers/gpu/drm/xe/xe_svm.h b/drivers/gpu/drm/xe/xe_svm.h
> index 3d441eb1f7ea..8bc83de87250 100644
> --- a/drivers/gpu/drm/xe/xe_svm.h
> +++ b/drivers/gpu/drm/xe/xe_svm.h
> @@ -84,7 +84,7 @@ void xe_svm_range_debug(struct xe_svm_range *range, const
> char *operation);
> static inline bool xe_svm_range_has_dma_mapping(struct xe_svm_range *range)
> {
> lockdep_assert_held(&range->base.gpusvm->notifier_lock);
> - return range->base.flags.has_dma_mapping;
> + return range->base.pages.flags.has_dma_mapping;
> }
>
> #define xe_svm_assert_in_notifier(vm__) \
> @@ -112,7 +112,9 @@ struct xe_vram_region;
> struct xe_svm_range {
> struct {
> struct interval_tree_node itree;
> - const struct drm_pagemap_device_addr *dma_addr;
> + struct {
> + struct drm_pagemap_device_addr *dma_addr;
> + } pages;
> } base;
> u32 tile_present;
> u32 tile_invalidated;
> diff --git a/include/drm/drm_gpusvm.h b/include/drm/drm_gpusvm.h
> index df120b4d1f83..1b7ed4f4a8e2 100644
> --- a/include/drm/drm_gpusvm.h
> +++ b/include/drm/drm_gpusvm.h
> @@ -185,6 +185,35 @@ struct drm_gpusvm_notifier {
> } flags;
> };
>
> +/**
> + * struct drm_gpusvm_pages - Structure representing a GPU SVM mapped pages
> + *
> + * @dma_addr: Device address array
> + * @dpagemap: The struct drm_pagemap of the device pages we're dma-mapping.
> + * Note this is assuming only one drm_pagemap per range is
> allowed.
> + * @notifier_seq: Notifier sequence number of the range's pages
> + * @flags: Flags for range
> + * @flags.migrate_devmem: Flag indicating whether the range can be migrated
> to device memory
> + * @flags.unmapped: Flag indicating if the range has been unmapped
> + * @flags.partial_unmap: Flag indicating if the range has been partially
> unmapped
> + * @flags.has_devmem_pages: Flag indicating if the range has devmem pages
> + * @flags.has_dma_mapping: Flag indicating if the range has a DMA mapping
> + */
> +struct drm_gpusvm_pages {
> + struct drm_pagemap_device_addr *dma_addr;
> + struct drm_pagemap *dpagemap;
> + unsigned long notifier_seq;
> + struct {
> + /* All flags below must be set upon creation */
> + u16 migrate_devmem : 1;
> + /* All flags below must be set / cleared under notifier lock */
> + u16 unmapped : 1;
> + u16 partial_unmap : 1;
> + u16 has_devmem_pages : 1;
> + u16 has_dma_mapping : 1;
> + } flags;
> +};
> +
> /**
> * struct drm_gpusvm_range - Structure representing a GPU SVM range
> *
> @@ -193,16 +222,7 @@ struct drm_gpusvm_notifier {
> * @refcount: Reference count for the range
> * @itree: Interval tree node for the range (inserted in GPU SVM notifier)
> * @entry: List entry to fast interval tree traversal
> - * @notifier_seq: Notifier sequence number of the range's pages
> - * @dma_addr: Device address array
> - * @dpagemap: The struct drm_pagemap of the device pages we're dma-mapping.
> - * Note this is assuming only one drm_pagemap per range is
> allowed.
> - * @flags: Flags for range
> - * @flags.migrate_devmem: Flag indicating whether the range can be migrated
> to device memory
> - * @flags.unmapped: Flag indicating if the range has been unmapped
> - * @flags.partial_unmap: Flag indicating if the range has been partially
> unmapped
> - * @flags.has_devmem_pages: Flag indicating if the range has devmem pages
> - * @flags.has_dma_mapping: Flag indicating if the range has a DMA mapping
> + * @pages: The pages for this range.
> *
> * This structure represents a GPU SVM range used for tracking memory ranges
> * mapped in a DRM device.
> @@ -213,18 +233,7 @@ struct drm_gpusvm_range {
> struct kref refcount;
> struct interval_tree_node itree;
> struct list_head entry;
> - unsigned long notifier_seq;
> - struct drm_pagemap_device_addr *dma_addr;
> - struct drm_pagemap *dpagemap;
> - struct {
> - /* All flags below must be set upon creation */
> - u16 migrate_devmem : 1;
> - /* All flags below must be set / cleared under notifier lock */
> - u16 unmapped : 1;
> - u16 partial_unmap : 1;
> - u16 has_devmem_pages : 1;
> - u16 has_dma_mapping : 1;
> - } flags;
> + struct drm_gpusvm_pages pages;
> };
>
> /**
> --
> 2.48.1
>
