Implement the DRM pagemap IOVA vfuncs on top of the dma-map IOVA API. Also add lockdep annotations to verify that the locking guidelines are followed, paving the way for future implementations of the remaining IOVA vfuncs.
Signed-off-by: Matthew Brost <[email protected]> --- drivers/gpu/drm/xe/xe_svm.c | 117 +++++++++++++++++++++++++++++++++++- 1 file changed, 116 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c index c2a6bb367e0a..b46de21ed438 100644 --- a/drivers/gpu/drm/xe/xe_svm.c +++ b/drivers/gpu/drm/xe/xe_svm.c @@ -1660,14 +1660,125 @@ int xe_svm_alloc_vram(struct xe_svm_range *range, const struct drm_gpusvm_ctx *c return err; } +static void xe_drm_pagemap_device_iova_prove_locking(bool *locking_proved) +{ + struct ww_acquire_ctx ctx; + struct dma_resv obj; + int ret; + + if (!IS_ENABLED(CONFIG_PROVE_LOCKING)) + return; + + if (*locking_proved) + return; + + might_alloc(GFP_KERNEL); + + dma_resv_init(&obj); + ww_acquire_init(&ctx, &reservation_ww_class); + ret = dma_resv_lock(&obj, &ctx); + if (ret == -EDEADLK) + dma_resv_lock_slow(&obj, &ctx); + ww_mutex_unlock(&obj.lock); + ww_acquire_fini(&ctx); + + *locking_proved = true; +} + +struct xe_svm_iova_cookie { + struct dma_iova_state state; +}; + static void *xe_drm_pagemap_device_iova_alloc(struct drm_pagemap *dpagemap, struct device *dev, size_t length, enum dma_data_direction dir) { - /* NIY */ + struct device *pgmap_dev = dpagemap->drm->dev; + struct xe_svm_iova_cookie *cookie; + static bool locking_proved = false; + + xe_drm_pagemap_device_iova_prove_locking(&locking_proved); + + if (pgmap_dev == dev) + return NULL; + + cookie = kzalloc(sizeof(*cookie), GFP_KERNEL); + if (!cookie) + return NULL; + + dma_iova_try_alloc(dev, &cookie->state, length >= SZ_2M ? SZ_2M : 0, + length); + if (dma_use_iova(&cookie->state)) + return cookie; + + kfree(cookie); return NULL; } +static void xe_drm_pagemap_device_iova_free(struct drm_pagemap *dpagemap, + struct device *dev, size_t length, + void *cookie) +{ + struct xe_svm_iova_cookie *__cookie = cookie; + struct xe_device *xe = to_xe_device(dpagemap->drm); + static bool locking_proved = false; + + xe_assert(xe, dma_use_iova(&__cookie->state)); + xe_drm_pagemap_device_iova_prove_locking(&locking_proved); + + dma_iova_free(dev, &__cookie->state); + kfree(cookie); +} + +static struct drm_pagemap_addr +xe_drm_pagemap_device_iova_link(struct drm_pagemap *dpagemap, + struct device *dev, struct page *page, + size_t length, size_t offset, void *cookie, + enum dma_data_direction dir) +{ + struct xe_svm_iova_cookie *__cookie = cookie; + struct xe_device *xe = to_xe_device(dpagemap->drm); + dma_addr_t addr = __cookie->state.addr + offset; + int err; + + xe_assert(xe, dma_use_iova(&__cookie->state)); + + err = dma_iova_link(dev, &__cookie->state, xe_page_to_pcie(page), + offset, length, dir, DMA_ATTR_SKIP_CPU_SYNC | + DMA_ATTR_MMIO); + if (err) + addr = DMA_MAPPING_ERROR; + + return drm_pagemap_addr_encode(addr, XE_INTERCONNECT_P2P, ilog2(length), + dir); +} + +static int +xe_drm_pagemap_device_iova_sync(struct drm_pagemap *dpagemap, + struct device *dev, size_t length, void *cookie) +{ + struct xe_svm_iova_cookie *__cookie = cookie; + struct xe_device *xe = to_xe_device(dpagemap->drm); + + xe_assert(xe, dma_use_iova(&__cookie->state)); + + return dma_iova_sync(dev, &__cookie->state, 0, length); +} + +static void +xe_drm_pagemap_device_iova_unlink(struct drm_pagemap *dpagemap, + struct device *dev, size_t length, + void *cookie, enum dma_data_direction dir) +{ + struct xe_svm_iova_cookie *__cookie = cookie; + struct xe_device *xe = to_xe_device(dpagemap->drm); + + xe_assert(xe, dma_use_iova(&__cookie->state)); + + dma_iova_unlink(dev, &__cookie->state, 0, length, dir, + DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO); +} + static struct drm_pagemap_addr xe_drm_pagemap_device_map(struct drm_pagemap *dpagemap, struct device *dev, @@ -1740,6 +1851,10 @@ static void xe_pagemap_destroy(struct drm_pagemap *dpagemap, bool from_atomic_or static const struct drm_pagemap_ops xe_drm_pagemap_ops = { .device_iova_alloc = xe_drm_pagemap_device_iova_alloc, + .device_iova_free = xe_drm_pagemap_device_iova_free, + .device_iova_link = xe_drm_pagemap_device_iova_link, + .device_iova_sync = xe_drm_pagemap_device_iova_sync, + .device_iova_unlink = xe_drm_pagemap_device_iova_unlink, .device_map = xe_drm_pagemap_device_map, .device_unmap = xe_drm_pagemap_device_unmap, .populate_mm = xe_drm_pagemap_populate_mm, -- 2.34.1
