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-rw-r--r--drivers/gpu/drm/ttm/ttm_bo.c1220
1 files changed, 1220 insertions, 0 deletions
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
new file mode 100644
index 000000000..e58b7e249
--- /dev/null
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -0,0 +1,1220 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+/**************************************************************************
+ *
+ * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+/*
+ * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
+ */
+
+#define pr_fmt(fmt) "[TTM] " fmt
+
+#include <drm/ttm/ttm_bo.h>
+#include <drm/ttm/ttm_placement.h>
+#include <drm/ttm/ttm_tt.h>
+
+#include <linux/jiffies.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/file.h>
+#include <linux/module.h>
+#include <linux/atomic.h>
+#include <linux/dma-resv.h>
+
+#include "ttm_module.h"
+
+static void ttm_bo_mem_space_debug(struct ttm_buffer_object *bo,
+ struct ttm_placement *placement)
+{
+ struct drm_printer p = drm_debug_printer(TTM_PFX);
+ struct ttm_resource_manager *man;
+ int i, mem_type;
+
+ for (i = 0; i < placement->num_placement; i++) {
+ mem_type = placement->placement[i].mem_type;
+ drm_printf(&p, " placement[%d]=0x%08X (%d)\n",
+ i, placement->placement[i].flags, mem_type);
+ man = ttm_manager_type(bo->bdev, mem_type);
+ ttm_resource_manager_debug(man, &p);
+ }
+}
+
+/**
+ * ttm_bo_move_to_lru_tail
+ *
+ * @bo: The buffer object.
+ *
+ * Move this BO to the tail of all lru lists used to lookup and reserve an
+ * object. This function must be called with struct ttm_global::lru_lock
+ * held, and is used to make a BO less likely to be considered for eviction.
+ */
+void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo)
+{
+ dma_resv_assert_held(bo->base.resv);
+
+ if (bo->resource)
+ ttm_resource_move_to_lru_tail(bo->resource);
+}
+EXPORT_SYMBOL(ttm_bo_move_to_lru_tail);
+
+/**
+ * ttm_bo_set_bulk_move - update BOs bulk move object
+ *
+ * @bo: The buffer object.
+ * @bulk: bulk move structure
+ *
+ * Update the BOs bulk move object, making sure that resources are added/removed
+ * as well. A bulk move allows to move many resource on the LRU at once,
+ * resulting in much less overhead of maintaining the LRU.
+ * The only requirement is that the resources stay together on the LRU and are
+ * never separated. This is enforces by setting the bulk_move structure on a BO.
+ * ttm_lru_bulk_move_tail() should be used to move all resources to the tail of
+ * their LRU list.
+ */
+void ttm_bo_set_bulk_move(struct ttm_buffer_object *bo,
+ struct ttm_lru_bulk_move *bulk)
+{
+ dma_resv_assert_held(bo->base.resv);
+
+ if (bo->bulk_move == bulk)
+ return;
+
+ spin_lock(&bo->bdev->lru_lock);
+ if (bo->resource)
+ ttm_resource_del_bulk_move(bo->resource, bo);
+ bo->bulk_move = bulk;
+ if (bo->resource)
+ ttm_resource_add_bulk_move(bo->resource, bo);
+ spin_unlock(&bo->bdev->lru_lock);
+}
+EXPORT_SYMBOL(ttm_bo_set_bulk_move);
+
+static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,
+ struct ttm_resource *mem, bool evict,
+ struct ttm_operation_ctx *ctx,
+ struct ttm_place *hop)
+{
+ struct ttm_device *bdev = bo->bdev;
+ bool old_use_tt, new_use_tt;
+ int ret;
+
+ old_use_tt = !bo->resource || ttm_manager_type(bdev, bo->resource->mem_type)->use_tt;
+ new_use_tt = ttm_manager_type(bdev, mem->mem_type)->use_tt;
+
+ ttm_bo_unmap_virtual(bo);
+
+ /*
+ * Create and bind a ttm if required.
+ */
+
+ if (new_use_tt) {
+ /* Zero init the new TTM structure if the old location should
+ * have used one as well.
+ */
+ ret = ttm_tt_create(bo, old_use_tt);
+ if (ret)
+ goto out_err;
+
+ if (mem->mem_type != TTM_PL_SYSTEM) {
+ ret = ttm_tt_populate(bo->bdev, bo->ttm, ctx);
+ if (ret)
+ goto out_err;
+ }
+ }
+
+ ret = dma_resv_reserve_fences(bo->base.resv, 1);
+ if (ret)
+ goto out_err;
+
+ ret = bdev->funcs->move(bo, evict, ctx, mem, hop);
+ if (ret) {
+ if (ret == -EMULTIHOP)
+ return ret;
+ goto out_err;
+ }
+
+ ctx->bytes_moved += bo->base.size;
+ return 0;
+
+out_err:
+ if (!old_use_tt)
+ ttm_bo_tt_destroy(bo);
+
+ return ret;
+}
+
+/*
+ * Call bo::reserved.
+ * Will release GPU memory type usage on destruction.
+ * This is the place to put in driver specific hooks to release
+ * driver private resources.
+ * Will release the bo::reserved lock.
+ */
+
+static void ttm_bo_cleanup_memtype_use(struct ttm_buffer_object *bo)
+{
+ if (bo->bdev->funcs->delete_mem_notify)
+ bo->bdev->funcs->delete_mem_notify(bo);
+
+ ttm_bo_tt_destroy(bo);
+ ttm_resource_free(bo, &bo->resource);
+}
+
+static int ttm_bo_individualize_resv(struct ttm_buffer_object *bo)
+{
+ int r;
+
+ if (bo->base.resv == &bo->base._resv)
+ return 0;
+
+ BUG_ON(!dma_resv_trylock(&bo->base._resv));
+
+ r = dma_resv_copy_fences(&bo->base._resv, bo->base.resv);
+ dma_resv_unlock(&bo->base._resv);
+ if (r)
+ return r;
+
+ if (bo->type != ttm_bo_type_sg) {
+ /* This works because the BO is about to be destroyed and nobody
+ * reference it any more. The only tricky case is the trylock on
+ * the resv object while holding the lru_lock.
+ */
+ spin_lock(&bo->bdev->lru_lock);
+ bo->base.resv = &bo->base._resv;
+ spin_unlock(&bo->bdev->lru_lock);
+ }
+
+ return r;
+}
+
+static void ttm_bo_flush_all_fences(struct ttm_buffer_object *bo)
+{
+ struct dma_resv *resv = &bo->base._resv;
+ struct dma_resv_iter cursor;
+ struct dma_fence *fence;
+
+ dma_resv_iter_begin(&cursor, resv, DMA_RESV_USAGE_BOOKKEEP);
+ dma_resv_for_each_fence_unlocked(&cursor, fence) {
+ if (!fence->ops->signaled)
+ dma_fence_enable_sw_signaling(fence);
+ }
+ dma_resv_iter_end(&cursor);
+}
+
+/**
+ * ttm_bo_cleanup_refs
+ * If bo idle, remove from lru lists, and unref.
+ * If not idle, block if possible.
+ *
+ * Must be called with lru_lock and reservation held, this function
+ * will drop the lru lock and optionally the reservation lock before returning.
+ *
+ * @bo: The buffer object to clean-up
+ * @interruptible: Any sleeps should occur interruptibly.
+ * @no_wait_gpu: Never wait for gpu. Return -EBUSY instead.
+ * @unlock_resv: Unlock the reservation lock as well.
+ */
+
+static int ttm_bo_cleanup_refs(struct ttm_buffer_object *bo,
+ bool interruptible, bool no_wait_gpu,
+ bool unlock_resv)
+{
+ struct dma_resv *resv = &bo->base._resv;
+ int ret;
+
+ if (dma_resv_test_signaled(resv, DMA_RESV_USAGE_BOOKKEEP))
+ ret = 0;
+ else
+ ret = -EBUSY;
+
+ if (ret && !no_wait_gpu) {
+ long lret;
+
+ if (unlock_resv)
+ dma_resv_unlock(bo->base.resv);
+ spin_unlock(&bo->bdev->lru_lock);
+
+ lret = dma_resv_wait_timeout(resv, DMA_RESV_USAGE_BOOKKEEP,
+ interruptible,
+ 30 * HZ);
+
+ if (lret < 0)
+ return lret;
+ else if (lret == 0)
+ return -EBUSY;
+
+ spin_lock(&bo->bdev->lru_lock);
+ if (unlock_resv && !dma_resv_trylock(bo->base.resv)) {
+ /*
+ * We raced, and lost, someone else holds the reservation now,
+ * and is probably busy in ttm_bo_cleanup_memtype_use.
+ *
+ * Even if it's not the case, because we finished waiting any
+ * delayed destruction would succeed, so just return success
+ * here.
+ */
+ spin_unlock(&bo->bdev->lru_lock);
+ return 0;
+ }
+ ret = 0;
+ }
+
+ if (ret) {
+ if (unlock_resv)
+ dma_resv_unlock(bo->base.resv);
+ spin_unlock(&bo->bdev->lru_lock);
+ return ret;
+ }
+
+ spin_unlock(&bo->bdev->lru_lock);
+ ttm_bo_cleanup_memtype_use(bo);
+
+ if (unlock_resv)
+ dma_resv_unlock(bo->base.resv);
+
+ return 0;
+}
+
+/*
+ * Block for the dma_resv object to become idle, lock the buffer and clean up
+ * the resource and tt object.
+ */
+static void ttm_bo_delayed_delete(struct work_struct *work)
+{
+ struct ttm_buffer_object *bo;
+
+ bo = container_of(work, typeof(*bo), delayed_delete);
+
+ dma_resv_wait_timeout(bo->base.resv, DMA_RESV_USAGE_BOOKKEEP, false,
+ MAX_SCHEDULE_TIMEOUT);
+ dma_resv_lock(bo->base.resv, NULL);
+ ttm_bo_cleanup_memtype_use(bo);
+ dma_resv_unlock(bo->base.resv);
+ ttm_bo_put(bo);
+}
+
+static void ttm_bo_release(struct kref *kref)
+{
+ struct ttm_buffer_object *bo =
+ container_of(kref, struct ttm_buffer_object, kref);
+ struct ttm_device *bdev = bo->bdev;
+ int ret;
+
+ WARN_ON_ONCE(bo->pin_count);
+ WARN_ON_ONCE(bo->bulk_move);
+
+ if (!bo->deleted) {
+ ret = ttm_bo_individualize_resv(bo);
+ if (ret) {
+ /* Last resort, if we fail to allocate memory for the
+ * fences block for the BO to become idle
+ */
+ dma_resv_wait_timeout(bo->base.resv,
+ DMA_RESV_USAGE_BOOKKEEP, false,
+ 30 * HZ);
+ }
+
+ if (bo->bdev->funcs->release_notify)
+ bo->bdev->funcs->release_notify(bo);
+
+ drm_vma_offset_remove(bdev->vma_manager, &bo->base.vma_node);
+ ttm_mem_io_free(bdev, bo->resource);
+
+ if (!dma_resv_test_signaled(bo->base.resv,
+ DMA_RESV_USAGE_BOOKKEEP) ||
+ (want_init_on_free() && (bo->ttm != NULL)) ||
+ !dma_resv_trylock(bo->base.resv)) {
+ /* The BO is not idle, resurrect it for delayed destroy */
+ ttm_bo_flush_all_fences(bo);
+ bo->deleted = true;
+
+ spin_lock(&bo->bdev->lru_lock);
+
+ /*
+ * Make pinned bos immediately available to
+ * shrinkers, now that they are queued for
+ * destruction.
+ *
+ * FIXME: QXL is triggering this. Can be removed when the
+ * driver is fixed.
+ */
+ if (bo->pin_count) {
+ bo->pin_count = 0;
+ ttm_resource_move_to_lru_tail(bo->resource);
+ }
+
+ kref_init(&bo->kref);
+ spin_unlock(&bo->bdev->lru_lock);
+
+ INIT_WORK(&bo->delayed_delete, ttm_bo_delayed_delete);
+ queue_work(bdev->wq, &bo->delayed_delete);
+ return;
+ }
+
+ ttm_bo_cleanup_memtype_use(bo);
+ dma_resv_unlock(bo->base.resv);
+ }
+
+ atomic_dec(&ttm_glob.bo_count);
+ bo->destroy(bo);
+}
+
+/**
+ * ttm_bo_put
+ *
+ * @bo: The buffer object.
+ *
+ * Unreference a buffer object.
+ */
+void ttm_bo_put(struct ttm_buffer_object *bo)
+{
+ kref_put(&bo->kref, ttm_bo_release);
+}
+EXPORT_SYMBOL(ttm_bo_put);
+
+static int ttm_bo_bounce_temp_buffer(struct ttm_buffer_object *bo,
+ struct ttm_resource **mem,
+ struct ttm_operation_ctx *ctx,
+ struct ttm_place *hop)
+{
+ struct ttm_placement hop_placement;
+ struct ttm_resource *hop_mem;
+ int ret;
+
+ hop_placement.num_placement = hop_placement.num_busy_placement = 1;
+ hop_placement.placement = hop_placement.busy_placement = hop;
+
+ /* find space in the bounce domain */
+ ret = ttm_bo_mem_space(bo, &hop_placement, &hop_mem, ctx);
+ if (ret)
+ return ret;
+ /* move to the bounce domain */
+ ret = ttm_bo_handle_move_mem(bo, hop_mem, false, ctx, NULL);
+ if (ret) {
+ ttm_resource_free(bo, &hop_mem);
+ return ret;
+ }
+ return 0;
+}
+
+static int ttm_bo_evict(struct ttm_buffer_object *bo,
+ struct ttm_operation_ctx *ctx)
+{
+ struct ttm_device *bdev = bo->bdev;
+ struct ttm_resource *evict_mem;
+ struct ttm_placement placement;
+ struct ttm_place hop;
+ int ret = 0;
+
+ memset(&hop, 0, sizeof(hop));
+
+ dma_resv_assert_held(bo->base.resv);
+
+ placement.num_placement = 0;
+ placement.num_busy_placement = 0;
+ bdev->funcs->evict_flags(bo, &placement);
+
+ if (!placement.num_placement && !placement.num_busy_placement) {
+ ret = ttm_bo_wait_ctx(bo, ctx);
+ if (ret)
+ return ret;
+
+ /*
+ * Since we've already synced, this frees backing store
+ * immediately.
+ */
+ return ttm_bo_pipeline_gutting(bo);
+ }
+
+ ret = ttm_bo_mem_space(bo, &placement, &evict_mem, ctx);
+ if (ret) {
+ if (ret != -ERESTARTSYS) {
+ pr_err("Failed to find memory space for buffer 0x%p eviction\n",
+ bo);
+ ttm_bo_mem_space_debug(bo, &placement);
+ }
+ goto out;
+ }
+
+ do {
+ ret = ttm_bo_handle_move_mem(bo, evict_mem, true, ctx, &hop);
+ if (ret != -EMULTIHOP)
+ break;
+
+ ret = ttm_bo_bounce_temp_buffer(bo, &evict_mem, ctx, &hop);
+ } while (!ret);
+
+ if (ret) {
+ ttm_resource_free(bo, &evict_mem);
+ if (ret != -ERESTARTSYS && ret != -EINTR)
+ pr_err("Buffer eviction failed\n");
+ }
+out:
+ return ret;
+}
+
+/**
+ * ttm_bo_eviction_valuable
+ *
+ * @bo: The buffer object to evict
+ * @place: the placement we need to make room for
+ *
+ * Check if it is valuable to evict the BO to make room for the given placement.
+ */
+bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
+ const struct ttm_place *place)
+{
+ struct ttm_resource *res = bo->resource;
+ struct ttm_device *bdev = bo->bdev;
+
+ dma_resv_assert_held(bo->base.resv);
+ if (bo->resource->mem_type == TTM_PL_SYSTEM)
+ return true;
+
+ /* Don't evict this BO if it's outside of the
+ * requested placement range
+ */
+ return ttm_resource_intersects(bdev, res, place, bo->base.size);
+}
+EXPORT_SYMBOL(ttm_bo_eviction_valuable);
+
+/*
+ * Check the target bo is allowable to be evicted or swapout, including cases:
+ *
+ * a. if share same reservation object with ctx->resv, have assumption
+ * reservation objects should already be locked, so not lock again and
+ * return true directly when either the opreation allow_reserved_eviction
+ * or the target bo already is in delayed free list;
+ *
+ * b. Otherwise, trylock it.
+ */
+static bool ttm_bo_evict_swapout_allowable(struct ttm_buffer_object *bo,
+ struct ttm_operation_ctx *ctx,
+ const struct ttm_place *place,
+ bool *locked, bool *busy)
+{
+ bool ret = false;
+
+ if (bo->pin_count) {
+ *locked = false;
+ if (busy)
+ *busy = false;
+ return false;
+ }
+
+ if (bo->base.resv == ctx->resv) {
+ dma_resv_assert_held(bo->base.resv);
+ if (ctx->allow_res_evict)
+ ret = true;
+ *locked = false;
+ if (busy)
+ *busy = false;
+ } else {
+ ret = dma_resv_trylock(bo->base.resv);
+ *locked = ret;
+ if (busy)
+ *busy = !ret;
+ }
+
+ if (ret && place && (bo->resource->mem_type != place->mem_type ||
+ !bo->bdev->funcs->eviction_valuable(bo, place))) {
+ ret = false;
+ if (*locked) {
+ dma_resv_unlock(bo->base.resv);
+ *locked = false;
+ }
+ }
+
+ return ret;
+}
+
+/**
+ * ttm_mem_evict_wait_busy - wait for a busy BO to become available
+ *
+ * @busy_bo: BO which couldn't be locked with trylock
+ * @ctx: operation context
+ * @ticket: acquire ticket
+ *
+ * Try to lock a busy buffer object to avoid failing eviction.
+ */
+static int ttm_mem_evict_wait_busy(struct ttm_buffer_object *busy_bo,
+ struct ttm_operation_ctx *ctx,
+ struct ww_acquire_ctx *ticket)
+{
+ int r;
+
+ if (!busy_bo || !ticket)
+ return -EBUSY;
+
+ if (ctx->interruptible)
+ r = dma_resv_lock_interruptible(busy_bo->base.resv,
+ ticket);
+ else
+ r = dma_resv_lock(busy_bo->base.resv, ticket);
+
+ /*
+ * TODO: It would be better to keep the BO locked until allocation is at
+ * least tried one more time, but that would mean a much larger rework
+ * of TTM.
+ */
+ if (!r)
+ dma_resv_unlock(busy_bo->base.resv);
+
+ return r == -EDEADLK ? -EBUSY : r;
+}
+
+int ttm_mem_evict_first(struct ttm_device *bdev,
+ struct ttm_resource_manager *man,
+ const struct ttm_place *place,
+ struct ttm_operation_ctx *ctx,
+ struct ww_acquire_ctx *ticket)
+{
+ struct ttm_buffer_object *bo = NULL, *busy_bo = NULL;
+ struct ttm_resource_cursor cursor;
+ struct ttm_resource *res;
+ bool locked = false;
+ int ret;
+
+ spin_lock(&bdev->lru_lock);
+ ttm_resource_manager_for_each_res(man, &cursor, res) {
+ bool busy;
+
+ if (!ttm_bo_evict_swapout_allowable(res->bo, ctx, place,
+ &locked, &busy)) {
+ if (busy && !busy_bo && ticket !=
+ dma_resv_locking_ctx(res->bo->base.resv))
+ busy_bo = res->bo;
+ continue;
+ }
+
+ if (ttm_bo_get_unless_zero(res->bo)) {
+ bo = res->bo;
+ break;
+ }
+ if (locked)
+ dma_resv_unlock(res->bo->base.resv);
+ }
+
+ if (!bo) {
+ if (busy_bo && !ttm_bo_get_unless_zero(busy_bo))
+ busy_bo = NULL;
+ spin_unlock(&bdev->lru_lock);
+ ret = ttm_mem_evict_wait_busy(busy_bo, ctx, ticket);
+ if (busy_bo)
+ ttm_bo_put(busy_bo);
+ return ret;
+ }
+
+ if (bo->deleted) {
+ ret = ttm_bo_cleanup_refs(bo, ctx->interruptible,
+ ctx->no_wait_gpu, locked);
+ ttm_bo_put(bo);
+ return ret;
+ }
+
+ spin_unlock(&bdev->lru_lock);
+
+ ret = ttm_bo_evict(bo, ctx);
+ if (locked)
+ ttm_bo_unreserve(bo);
+ else
+ ttm_bo_move_to_lru_tail_unlocked(bo);
+
+ ttm_bo_put(bo);
+ return ret;
+}
+
+/**
+ * ttm_bo_pin - Pin the buffer object.
+ * @bo: The buffer object to pin
+ *
+ * Make sure the buffer is not evicted any more during memory pressure.
+ * @bo must be unpinned again by calling ttm_bo_unpin().
+ */
+void ttm_bo_pin(struct ttm_buffer_object *bo)
+{
+ dma_resv_assert_held(bo->base.resv);
+ WARN_ON_ONCE(!kref_read(&bo->kref));
+ spin_lock(&bo->bdev->lru_lock);
+ if (bo->resource)
+ ttm_resource_del_bulk_move(bo->resource, bo);
+ ++bo->pin_count;
+ spin_unlock(&bo->bdev->lru_lock);
+}
+EXPORT_SYMBOL(ttm_bo_pin);
+
+/**
+ * ttm_bo_unpin - Unpin the buffer object.
+ * @bo: The buffer object to unpin
+ *
+ * Allows the buffer object to be evicted again during memory pressure.
+ */
+void ttm_bo_unpin(struct ttm_buffer_object *bo)
+{
+ dma_resv_assert_held(bo->base.resv);
+ WARN_ON_ONCE(!kref_read(&bo->kref));
+ if (WARN_ON_ONCE(!bo->pin_count))
+ return;
+
+ spin_lock(&bo->bdev->lru_lock);
+ --bo->pin_count;
+ if (bo->resource)
+ ttm_resource_add_bulk_move(bo->resource, bo);
+ spin_unlock(&bo->bdev->lru_lock);
+}
+EXPORT_SYMBOL(ttm_bo_unpin);
+
+/*
+ * Add the last move fence to the BO as kernel dependency and reserve a new
+ * fence slot.
+ */
+static int ttm_bo_add_move_fence(struct ttm_buffer_object *bo,
+ struct ttm_resource_manager *man,
+ struct ttm_resource *mem,
+ bool no_wait_gpu)
+{
+ struct dma_fence *fence;
+ int ret;
+
+ spin_lock(&man->move_lock);
+ fence = dma_fence_get(man->move);
+ spin_unlock(&man->move_lock);
+
+ if (!fence)
+ return 0;
+
+ if (no_wait_gpu) {
+ ret = dma_fence_is_signaled(fence) ? 0 : -EBUSY;
+ dma_fence_put(fence);
+ return ret;
+ }
+
+ dma_resv_add_fence(bo->base.resv, fence, DMA_RESV_USAGE_KERNEL);
+
+ ret = dma_resv_reserve_fences(bo->base.resv, 1);
+ dma_fence_put(fence);
+ return ret;
+}
+
+/*
+ * Repeatedly evict memory from the LRU for @mem_type until we create enough
+ * space, or we've evicted everything and there isn't enough space.
+ */
+static int ttm_bo_mem_force_space(struct ttm_buffer_object *bo,
+ const struct ttm_place *place,
+ struct ttm_resource **mem,
+ struct ttm_operation_ctx *ctx)
+{
+ struct ttm_device *bdev = bo->bdev;
+ struct ttm_resource_manager *man;
+ struct ww_acquire_ctx *ticket;
+ int ret;
+
+ man = ttm_manager_type(bdev, place->mem_type);
+ ticket = dma_resv_locking_ctx(bo->base.resv);
+ do {
+ ret = ttm_resource_alloc(bo, place, mem);
+ if (likely(!ret))
+ break;
+ if (unlikely(ret != -ENOSPC))
+ return ret;
+ ret = ttm_mem_evict_first(bdev, man, place, ctx,
+ ticket);
+ if (unlikely(ret != 0))
+ return ret;
+ } while (1);
+
+ return ttm_bo_add_move_fence(bo, man, *mem, ctx->no_wait_gpu);
+}
+
+/**
+ * ttm_bo_mem_space
+ *
+ * @bo: Pointer to a struct ttm_buffer_object. the data of which
+ * we want to allocate space for.
+ * @placement: Proposed new placement for the buffer object.
+ * @mem: A struct ttm_resource.
+ * @ctx: if and how to sleep, lock buffers and alloc memory
+ *
+ * Allocate memory space for the buffer object pointed to by @bo, using
+ * the placement flags in @placement, potentially evicting other idle buffer objects.
+ * This function may sleep while waiting for space to become available.
+ * Returns:
+ * -EBUSY: No space available (only if no_wait == 1).
+ * -ENOMEM: Could not allocate memory for the buffer object, either due to
+ * fragmentation or concurrent allocators.
+ * -ERESTARTSYS: An interruptible sleep was interrupted by a signal.
+ */
+int ttm_bo_mem_space(struct ttm_buffer_object *bo,
+ struct ttm_placement *placement,
+ struct ttm_resource **mem,
+ struct ttm_operation_ctx *ctx)
+{
+ struct ttm_device *bdev = bo->bdev;
+ bool type_found = false;
+ int i, ret;
+
+ ret = dma_resv_reserve_fences(bo->base.resv, 1);
+ if (unlikely(ret))
+ return ret;
+
+ for (i = 0; i < placement->num_placement; ++i) {
+ const struct ttm_place *place = &placement->placement[i];
+ struct ttm_resource_manager *man;
+
+ man = ttm_manager_type(bdev, place->mem_type);
+ if (!man || !ttm_resource_manager_used(man))
+ continue;
+
+ type_found = true;
+ ret = ttm_resource_alloc(bo, place, mem);
+ if (ret == -ENOSPC)
+ continue;
+ if (unlikely(ret))
+ goto error;
+
+ ret = ttm_bo_add_move_fence(bo, man, *mem, ctx->no_wait_gpu);
+ if (unlikely(ret)) {
+ ttm_resource_free(bo, mem);
+ if (ret == -EBUSY)
+ continue;
+
+ goto error;
+ }
+ return 0;
+ }
+
+ for (i = 0; i < placement->num_busy_placement; ++i) {
+ const struct ttm_place *place = &placement->busy_placement[i];
+ struct ttm_resource_manager *man;
+
+ man = ttm_manager_type(bdev, place->mem_type);
+ if (!man || !ttm_resource_manager_used(man))
+ continue;
+
+ type_found = true;
+ ret = ttm_bo_mem_force_space(bo, place, mem, ctx);
+ if (likely(!ret))
+ return 0;
+
+ if (ret && ret != -EBUSY)
+ goto error;
+ }
+
+ ret = -ENOMEM;
+ if (!type_found) {
+ pr_err(TTM_PFX "No compatible memory type found\n");
+ ret = -EINVAL;
+ }
+
+error:
+ return ret;
+}
+EXPORT_SYMBOL(ttm_bo_mem_space);
+
+static int ttm_bo_move_buffer(struct ttm_buffer_object *bo,
+ struct ttm_placement *placement,
+ struct ttm_operation_ctx *ctx)
+{
+ struct ttm_resource *mem;
+ struct ttm_place hop;
+ int ret;
+
+ dma_resv_assert_held(bo->base.resv);
+
+ /*
+ * Determine where to move the buffer.
+ *
+ * If driver determines move is going to need
+ * an extra step then it will return -EMULTIHOP
+ * and the buffer will be moved to the temporary
+ * stop and the driver will be called to make
+ * the second hop.
+ */
+ ret = ttm_bo_mem_space(bo, placement, &mem, ctx);
+ if (ret)
+ return ret;
+bounce:
+ ret = ttm_bo_handle_move_mem(bo, mem, false, ctx, &hop);
+ if (ret == -EMULTIHOP) {
+ ret = ttm_bo_bounce_temp_buffer(bo, &mem, ctx, &hop);
+ if (ret)
+ goto out;
+ /* try and move to final place now. */
+ goto bounce;
+ }
+out:
+ if (ret)
+ ttm_resource_free(bo, &mem);
+ return ret;
+}
+
+/**
+ * ttm_bo_validate
+ *
+ * @bo: The buffer object.
+ * @placement: Proposed placement for the buffer object.
+ * @ctx: validation parameters.
+ *
+ * Changes placement and caching policy of the buffer object
+ * according proposed placement.
+ * Returns
+ * -EINVAL on invalid proposed placement.
+ * -ENOMEM on out-of-memory condition.
+ * -EBUSY if no_wait is true and buffer busy.
+ * -ERESTARTSYS if interrupted by a signal.
+ */
+int ttm_bo_validate(struct ttm_buffer_object *bo,
+ struct ttm_placement *placement,
+ struct ttm_operation_ctx *ctx)
+{
+ int ret;
+
+ dma_resv_assert_held(bo->base.resv);
+
+ /*
+ * Remove the backing store if no placement is given.
+ */
+ if (!placement->num_placement && !placement->num_busy_placement)
+ return ttm_bo_pipeline_gutting(bo);
+
+ /* Check whether we need to move buffer. */
+ if (bo->resource && ttm_resource_compat(bo->resource, placement))
+ return 0;
+
+ /* Moving of pinned BOs is forbidden */
+ if (bo->pin_count)
+ return -EINVAL;
+
+ ret = ttm_bo_move_buffer(bo, placement, ctx);
+ if (ret)
+ return ret;
+
+ /*
+ * We might need to add a TTM.
+ */
+ if (!bo->resource || bo->resource->mem_type == TTM_PL_SYSTEM) {
+ ret = ttm_tt_create(bo, true);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(ttm_bo_validate);
+
+/**
+ * ttm_bo_init_reserved
+ *
+ * @bdev: Pointer to a ttm_device struct.
+ * @bo: Pointer to a ttm_buffer_object to be initialized.
+ * @type: Requested type of buffer object.
+ * @placement: Initial placement for buffer object.
+ * @alignment: Data alignment in pages.
+ * @ctx: TTM operation context for memory allocation.
+ * @sg: Scatter-gather table.
+ * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
+ * @destroy: Destroy function. Use NULL for kfree().
+ *
+ * This function initializes a pre-allocated struct ttm_buffer_object.
+ * As this object may be part of a larger structure, this function,
+ * together with the @destroy function, enables driver-specific objects
+ * derived from a ttm_buffer_object.
+ *
+ * On successful return, the caller owns an object kref to @bo. The kref and
+ * list_kref are usually set to 1, but note that in some situations, other
+ * tasks may already be holding references to @bo as well.
+ * Furthermore, if resv == NULL, the buffer's reservation lock will be held,
+ * and it is the caller's responsibility to call ttm_bo_unreserve.
+ *
+ * If a failure occurs, the function will call the @destroy function. Thus,
+ * after a failure, dereferencing @bo is illegal and will likely cause memory
+ * corruption.
+ *
+ * Returns
+ * -ENOMEM: Out of memory.
+ * -EINVAL: Invalid placement flags.
+ * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
+ */
+int ttm_bo_init_reserved(struct ttm_device *bdev, struct ttm_buffer_object *bo,
+ enum ttm_bo_type type, struct ttm_placement *placement,
+ uint32_t alignment, struct ttm_operation_ctx *ctx,
+ struct sg_table *sg, struct dma_resv *resv,
+ void (*destroy) (struct ttm_buffer_object *))
+{
+ int ret;
+
+ kref_init(&bo->kref);
+ bo->bdev = bdev;
+ bo->type = type;
+ bo->page_alignment = alignment;
+ bo->destroy = destroy;
+ bo->pin_count = 0;
+ bo->sg = sg;
+ bo->bulk_move = NULL;
+ if (resv)
+ bo->base.resv = resv;
+ else
+ bo->base.resv = &bo->base._resv;
+ atomic_inc(&ttm_glob.bo_count);
+
+ /*
+ * For ttm_bo_type_device buffers, allocate
+ * address space from the device.
+ */
+ if (bo->type == ttm_bo_type_device || bo->type == ttm_bo_type_sg) {
+ ret = drm_vma_offset_add(bdev->vma_manager, &bo->base.vma_node,
+ PFN_UP(bo->base.size));
+ if (ret)
+ goto err_put;
+ }
+
+ /* passed reservation objects should already be locked,
+ * since otherwise lockdep will be angered in radeon.
+ */
+ if (!resv)
+ WARN_ON(!dma_resv_trylock(bo->base.resv));
+ else
+ dma_resv_assert_held(resv);
+
+ ret = ttm_bo_validate(bo, placement, ctx);
+ if (unlikely(ret))
+ goto err_unlock;
+
+ return 0;
+
+err_unlock:
+ if (!resv)
+ dma_resv_unlock(bo->base.resv);
+
+err_put:
+ ttm_bo_put(bo);
+ return ret;
+}
+EXPORT_SYMBOL(ttm_bo_init_reserved);
+
+/**
+ * ttm_bo_init_validate
+ *
+ * @bdev: Pointer to a ttm_device struct.
+ * @bo: Pointer to a ttm_buffer_object to be initialized.
+ * @type: Requested type of buffer object.
+ * @placement: Initial placement for buffer object.
+ * @alignment: Data alignment in pages.
+ * @interruptible: If needing to sleep to wait for GPU resources,
+ * sleep interruptible.
+ * pinned in physical memory. If this behaviour is not desired, this member
+ * holds a pointer to a persistent shmem object. Typically, this would
+ * point to the shmem object backing a GEM object if TTM is used to back a
+ * GEM user interface.
+ * @sg: Scatter-gather table.
+ * @resv: Pointer to a dma_resv, or NULL to let ttm allocate one.
+ * @destroy: Destroy function. Use NULL for kfree().
+ *
+ * This function initializes a pre-allocated struct ttm_buffer_object.
+ * As this object may be part of a larger structure, this function,
+ * together with the @destroy function,
+ * enables driver-specific objects derived from a ttm_buffer_object.
+ *
+ * On successful return, the caller owns an object kref to @bo. The kref and
+ * list_kref are usually set to 1, but note that in some situations, other
+ * tasks may already be holding references to @bo as well.
+ *
+ * If a failure occurs, the function will call the @destroy function, Thus,
+ * after a failure, dereferencing @bo is illegal and will likely cause memory
+ * corruption.
+ *
+ * Returns
+ * -ENOMEM: Out of memory.
+ * -EINVAL: Invalid placement flags.
+ * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
+ */
+int ttm_bo_init_validate(struct ttm_device *bdev, struct ttm_buffer_object *bo,
+ enum ttm_bo_type type, struct ttm_placement *placement,
+ uint32_t alignment, bool interruptible,
+ struct sg_table *sg, struct dma_resv *resv,
+ void (*destroy) (struct ttm_buffer_object *))
+{
+ struct ttm_operation_ctx ctx = { interruptible, false };
+ int ret;
+
+ ret = ttm_bo_init_reserved(bdev, bo, type, placement, alignment, &ctx,
+ sg, resv, destroy);
+ if (ret)
+ return ret;
+
+ if (!resv)
+ ttm_bo_unreserve(bo);
+
+ return 0;
+}
+EXPORT_SYMBOL(ttm_bo_init_validate);
+
+/*
+ * buffer object vm functions.
+ */
+
+/**
+ * ttm_bo_unmap_virtual
+ *
+ * @bo: tear down the virtual mappings for this BO
+ */
+void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo)
+{
+ struct ttm_device *bdev = bo->bdev;
+
+ drm_vma_node_unmap(&bo->base.vma_node, bdev->dev_mapping);
+ ttm_mem_io_free(bdev, bo->resource);
+}
+EXPORT_SYMBOL(ttm_bo_unmap_virtual);
+
+/**
+ * ttm_bo_wait_ctx - wait for buffer idle.
+ *
+ * @bo: The buffer object.
+ * @ctx: defines how to wait
+ *
+ * Waits for the buffer to be idle. Used timeout depends on the context.
+ * Returns -EBUSY if wait timed outt, -ERESTARTSYS if interrupted by a signal or
+ * zero on success.
+ */
+int ttm_bo_wait_ctx(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx)
+{
+ long ret;
+
+ if (ctx->no_wait_gpu) {
+ if (dma_resv_test_signaled(bo->base.resv,
+ DMA_RESV_USAGE_BOOKKEEP))
+ return 0;
+ else
+ return -EBUSY;
+ }
+
+ ret = dma_resv_wait_timeout(bo->base.resv, DMA_RESV_USAGE_BOOKKEEP,
+ ctx->interruptible, 15 * HZ);
+ if (unlikely(ret < 0))
+ return ret;
+ if (unlikely(ret == 0))
+ return -EBUSY;
+ return 0;
+}
+EXPORT_SYMBOL(ttm_bo_wait_ctx);
+
+int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx,
+ gfp_t gfp_flags)
+{
+ struct ttm_place place;
+ bool locked;
+ long ret;
+
+ /*
+ * While the bo may already reside in SYSTEM placement, set
+ * SYSTEM as new placement to cover also the move further below.
+ * The driver may use the fact that we're moving from SYSTEM
+ * as an indication that we're about to swap out.
+ */
+ memset(&place, 0, sizeof(place));
+ place.mem_type = bo->resource->mem_type;
+ if (!ttm_bo_evict_swapout_allowable(bo, ctx, &place, &locked, NULL))
+ return -EBUSY;
+
+ if (!bo->ttm || !ttm_tt_is_populated(bo->ttm) ||
+ bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL ||
+ bo->ttm->page_flags & TTM_TT_FLAG_SWAPPED ||
+ !ttm_bo_get_unless_zero(bo)) {
+ if (locked)
+ dma_resv_unlock(bo->base.resv);
+ return -EBUSY;
+ }
+
+ if (bo->deleted) {
+ ret = ttm_bo_cleanup_refs(bo, false, false, locked);
+ ttm_bo_put(bo);
+ return ret == -EBUSY ? -ENOSPC : ret;
+ }
+
+ /* TODO: Cleanup the locking */
+ spin_unlock(&bo->bdev->lru_lock);
+
+ /*
+ * Move to system cached
+ */
+ if (bo->resource->mem_type != TTM_PL_SYSTEM) {
+ struct ttm_resource *evict_mem;
+ struct ttm_place hop;
+
+ memset(&hop, 0, sizeof(hop));
+ place.mem_type = TTM_PL_SYSTEM;
+ ret = ttm_resource_alloc(bo, &place, &evict_mem);
+ if (unlikely(ret))
+ goto out;
+
+ ret = ttm_bo_handle_move_mem(bo, evict_mem, true, ctx, &hop);
+ if (unlikely(ret != 0)) {
+ WARN(ret == -EMULTIHOP, "Unexpected multihop in swaput - likely driver bug.\n");
+ ttm_resource_free(bo, &evict_mem);
+ goto out;
+ }
+ }
+
+ /*
+ * Make sure BO is idle.
+ */
+ ret = ttm_bo_wait_ctx(bo, ctx);
+ if (unlikely(ret != 0))
+ goto out;
+
+ ttm_bo_unmap_virtual(bo);
+
+ /*
+ * Swap out. Buffer will be swapped in again as soon as
+ * anyone tries to access a ttm page.
+ */
+ if (bo->bdev->funcs->swap_notify)
+ bo->bdev->funcs->swap_notify(bo);
+
+ if (ttm_tt_is_populated(bo->ttm))
+ ret = ttm_tt_swapout(bo->bdev, bo->ttm, gfp_flags);
+out:
+
+ /*
+ * Unreserve without putting on LRU to avoid swapping out an
+ * already swapped buffer.
+ */
+ if (locked)
+ dma_resv_unlock(bo->base.resv);
+ ttm_bo_put(bo);
+ return ret == -EBUSY ? -ENOSPC : ret;
+}
+
+void ttm_bo_tt_destroy(struct ttm_buffer_object *bo)
+{
+ if (bo->ttm == NULL)
+ return;
+
+ ttm_tt_unpopulate(bo->bdev, bo->ttm);
+ ttm_tt_destroy(bo->bdev, bo->ttm);
+ bo->ttm = NULL;
+}