xref: /dragonfly/sys/dev/drm/i915/i915_gem_object.h (revision 3f2dd94a569761201b5b0a18b2f697f97fe1b9dc)

/*
 * Copyright © 2016 Intel Corporation
 *
 * 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, sublicense,
 * 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 NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS 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.
 *
 */

#ifndef __I915_GEM_OBJECT_H__
#define __I915_GEM_OBJECT_H__

#include <linux/reservation.h>

#include <drm/drm_vma_manager.h>
#include <drm/drm_gem.h>
#include <drm/drmP.h>

#include <drm/i915_drm.h>

#include "i915_gem_request.h"
#include "i915_selftest.h"

struct drm_i915_gem_object;

/*
 * struct i915_lut_handle tracks the fast lookups from handle to vma used
 * for execbuf. Although we use a radixtree for that mapping, in order to
 * remove them as the object or context is closed, we need a secondary list
 * and a translation entry (i915_lut_handle).
 */
struct i915_lut_handle {
          struct list_head obj_link;
          struct list_head ctx_link;
          struct i915_gem_context *ctx;
          u32 handle;
};

struct drm_i915_gem_object_ops {
          unsigned int flags;
#define I915_GEM_OBJECT_HAS_STRUCT_PAGE BIT(0)
#define I915_GEM_OBJECT_IS_SHRINKABLE   BIT(1)

          /* Interface between the GEM object and its backing storage.
           * get_pages() is called once prior to the use of the associated set
           * of pages before to binding them into the GTT, and put_pages() is
           * called after we no longer need them. As we expect there to be
           * associated cost with migrating pages between the backing storage
           * and making them available for the GPU (e.g. clflush), we may hold
           * onto the pages after they are no longer referenced by the GPU
           * in case they may be used again shortly (for example migrating the
           * pages to a different memory domain within the GTT). put_pages()
           * will therefore most likely be called when the object itself is
           * being released or under memory pressure (where we attempt to
           * reap pages for the shrinker).
           */
          int (*get_pages)(struct drm_i915_gem_object *);
          void (*put_pages)(struct drm_i915_gem_object *, struct sg_table *);

          int (*pwrite)(struct drm_i915_gem_object *,
                          const struct drm_i915_gem_pwrite *);

          int (*dmabuf_export)(struct drm_i915_gem_object *);
          void (*release)(struct drm_i915_gem_object *);
};

struct drm_i915_gem_object {
          struct drm_gem_object base;

          const struct drm_i915_gem_object_ops *ops;

          /**
           * @vma_list: List of VMAs backed by this object
           *
           * The VMA on this list are ordered by type, all GGTT vma are placed
           * at the head and all ppGTT vma are placed at the tail. The different
           * types of GGTT vma are unordered between themselves, use the
           * @vma_tree (which has a defined order between all VMA) to find an
           * exact match.
           */
          struct list_head vma_list;
          /**
           * @vma_tree: Ordered tree of VMAs backed by this object
           *
           * All VMA created for this object are placed in the @vma_tree for
           * fast retrieval via a binary search in i915_vma_instance().
           * They are also added to @vma_list for easy iteration.
           */
          struct rb_root vma_tree;

          /**
           * @lut_list: List of vma lookup entries in use for this object.
           *
           * If this object is closed, we need to remove all of its VMA from
           * the fast lookup index in associated contexts; @lut_list provides
           * this translation from object to context->handles_vma.
           */
          struct list_head lut_list;

          /** Stolen memory for this object, instead of being backed by shmem. */
          struct drm_mm_node *stolen;
          union {
                    struct rcu_head rcu;
                    struct llist_node freed;
          };

          /**
           * Whether the object is currently in the GGTT mmap.
           */
          unsigned int userfault_count;
          struct list_head userfault_link;

          struct list_head batch_pool_link;
          I915_SELFTEST_DECLARE(struct list_head st_link);

          unsigned long flags;

          /**
           * Have we taken a reference for the object for incomplete GPU
           * activity?
           */
#define I915_BO_ACTIVE_REF 0

          /*
           * Is the object to be mapped as read-only to the GPU
           * Only honoured if hardware has relevant pte bit
           */
          unsigned long gt_ro:1;
          unsigned int cache_level:3;
          unsigned int cache_coherent:2;
#define I915_BO_CACHE_COHERENT_FOR_READ BIT(0)
#define I915_BO_CACHE_COHERENT_FOR_WRITE BIT(1)
          unsigned int cache_dirty:1;

          atomic_t frontbuffer_bits;
          unsigned int frontbuffer_ggtt_origin; /* write once */
          struct i915_gem_active frontbuffer_write;

          /** Current tiling stride for the object, if it's tiled. */
          unsigned int tiling_and_stride;
#define FENCE_MINIMUM_STRIDE 128 /* See i915_tiling_ok() */
#define TILING_MASK (FENCE_MINIMUM_STRIDE-1)
#define STRIDE_MASK (~TILING_MASK)

          /** Count of VMA actually bound by this object */
          unsigned int bind_count;
          unsigned int active_count;
          /** Count of how many global VMA are currently pinned for use by HW */
          unsigned int pin_global;

          struct {
                    struct lock lock; /* protects the pages and their use */
                    atomic_t pages_pin_count;

                    struct sg_table *pages;
                    void *mapping;

                    /* TODO: whack some of this into the error state */
                    struct i915_page_sizes {
                              /**
                               * The sg mask of the pages sg_table. i.e the mask of
                               * of the lengths for each sg entry.
                               */
                              unsigned int phys;

                              /**
                               * The gtt page sizes we are allowed to use given the
                               * sg mask and the supported page sizes. This will
                               * express the smallest unit we can use for the whole
                               * object, as well as the larger sizes we may be able
                               * to use opportunistically.
                               */
                              unsigned int sg;

                              /**
                               * The actual gtt page size usage. Since we can have
                               * multiple vma associated with this object we need to
                               * prevent any trampling of state, hence a copy of this
                               * struct also lives in each vma, therefore the gtt
                               * value here should only be read/write through the vma.
                               */
                              unsigned int gtt;
                    } page_sizes;

                    I915_SELFTEST_DECLARE(unsigned int page_mask);

                    struct i915_gem_object_page_iter {
                              struct scatterlist *sg_pos;
                              unsigned int sg_idx; /* in pages, but 32bit eek! */

                              struct radix_tree_root radix;
                              struct lock lock; /* protects this cache */
                    } get_page;

                    /**
                     * Element within i915->mm.unbound_list or i915->mm.bound_list,
                     * locked by i915->mm.obj_lock.
                     */
                    struct list_head link;

                    /**
                     * Advice: are the backing pages purgeable?
                     */
                    unsigned int madv:2;

                    /**
                     * This is set if the object has been written to since the
                     * pages were last acquired.
                     */
                    bool dirty:1;

                    /**
                     * This is set if the object has been pinned due to unknown
                     * swizzling.
                     */
                    bool quirked:1;
          } mm;

          /** Breadcrumb of last rendering to the buffer.
           * There can only be one writer, but we allow for multiple readers.
           * If there is a writer that necessarily implies that all other
           * read requests are complete - but we may only be lazily clearing
           * the read requests. A read request is naturally the most recent
           * request on a ring, so we may have two different write and read
           * requests on one ring where the write request is older than the
           * read request. This allows for the CPU to read from an active
           * buffer by only waiting for the write to complete.
           */
          struct reservation_object *resv;

          /** References from framebuffers, locks out tiling changes. */
          unsigned int framebuffer_references;

          /** Record of address bit 17 of each page at last unbind. */
          unsigned long *bit_17;

          union {
                    struct i915_gem_userptr {
                              uintptr_t ptr;
                              unsigned read_only :1;

                              struct i915_mm_struct *mm;
                              struct i915_mmu_object *mmu_object;
                              struct work_struct *work;
                    } userptr;

                    unsigned long scratch;
          };

          /** for phys allocated objects */
          struct drm_dma_handle *phys_handle;

          struct reservation_object __builtin_resv;
};

static inline struct drm_i915_gem_object *
to_intel_bo(struct drm_gem_object *gem)
{
          /* Assert that to_intel_bo(NULL) == NULL */
          BUILD_BUG_ON(offsetof(struct drm_i915_gem_object, base));

          return container_of(gem, struct drm_i915_gem_object, base);
}

/**
 * i915_gem_object_lookup_rcu - look up a temporary GEM object from its handle
 * @filp: DRM file private date
 * @handle: userspace handle
 *
 * Returns:
 *
 * A pointer to the object named by the handle if such exists on @filp, NULL
 * otherwise. This object is only valid whilst under the RCU read lock, and
 * note carefully the object may be in the process of being destroyed.
 */
static inline struct drm_i915_gem_object *
i915_gem_object_lookup_rcu(struct drm_file *file, u32 handle)
{
#ifdef CONFIG_LOCKDEP
          WARN_ON(debug_locks && !lock_is_held(&rcu_lock_map));
#endif
          return idr_find(&file->object_idr, handle);
}

static inline struct drm_i915_gem_object *
i915_gem_object_lookup(struct drm_file *file, u32 handle)
{
          struct drm_i915_gem_object *obj;

          rcu_read_lock();
          obj = i915_gem_object_lookup_rcu(file, handle);
          if (obj && !kref_get_unless_zero(&obj->base.refcount))
                    obj = NULL;
          rcu_read_unlock();

          return obj;
}

__attribute__((nonnull))
static inline struct drm_i915_gem_object *
i915_gem_object_get(struct drm_i915_gem_object *obj)
{
          drm_gem_object_reference(&obj->base);
          return obj;
}

__attribute__((nonnull))
static inline void
i915_gem_object_put(struct drm_i915_gem_object *obj)
{
          __drm_gem_object_unreference(&obj->base);
}

static inline void i915_gem_object_lock(struct drm_i915_gem_object *obj)
{
          reservation_object_lock(obj->resv, NULL);
}

static inline void i915_gem_object_unlock(struct drm_i915_gem_object *obj)
{
          reservation_object_unlock(obj->resv);
}

static inline bool
i915_gem_object_has_struct_page(const struct drm_i915_gem_object *obj)
{
          return obj->ops->flags & I915_GEM_OBJECT_HAS_STRUCT_PAGE;
}

static inline bool
i915_gem_object_is_shrinkable(const struct drm_i915_gem_object *obj)
{
          return obj->ops->flags & I915_GEM_OBJECT_IS_SHRINKABLE;
}

static inline bool
i915_gem_object_is_active(const struct drm_i915_gem_object *obj)
{
          return obj->active_count;
}

static inline bool
i915_gem_object_has_active_reference(const struct drm_i915_gem_object *obj)
{
          return test_bit(I915_BO_ACTIVE_REF, &obj->flags);
}

static inline void
i915_gem_object_set_active_reference(struct drm_i915_gem_object *obj)
{
          lockdep_assert_held(&obj->base.dev->struct_mutex);
          __set_bit(I915_BO_ACTIVE_REF, &obj->flags);
}

static inline void
i915_gem_object_clear_active_reference(struct drm_i915_gem_object *obj)
{
          lockdep_assert_held(&obj->base.dev->struct_mutex);
          __clear_bit(I915_BO_ACTIVE_REF, &obj->flags);
}

void __i915_gem_object_release_unless_active(struct drm_i915_gem_object *obj);

static inline bool
i915_gem_object_is_framebuffer(const struct drm_i915_gem_object *obj)
{
          return READ_ONCE(obj->framebuffer_references);
}

static inline unsigned int
i915_gem_object_get_tiling(struct drm_i915_gem_object *obj)
{
          return obj->tiling_and_stride & TILING_MASK;
}

static inline bool
i915_gem_object_is_tiled(struct drm_i915_gem_object *obj)
{
          return i915_gem_object_get_tiling(obj) != I915_TILING_NONE;
}

static inline unsigned int
i915_gem_object_get_stride(struct drm_i915_gem_object *obj)
{
          return obj->tiling_and_stride & STRIDE_MASK;
}

static inline unsigned int
i915_gem_tile_height(unsigned int tiling)
{
          GEM_BUG_ON(!tiling);
          return tiling == I915_TILING_Y ? 32 : 8;
}

static inline unsigned int
i915_gem_object_get_tile_height(struct drm_i915_gem_object *obj)
{
          return i915_gem_tile_height(i915_gem_object_get_tiling(obj));
}

static inline unsigned int
i915_gem_object_get_tile_row_size(struct drm_i915_gem_object *obj)
{
          return (i915_gem_object_get_stride(obj) *
                    i915_gem_object_get_tile_height(obj));
}

int i915_gem_object_set_tiling(struct drm_i915_gem_object *obj,
                                     unsigned int tiling, unsigned int stride);

static inline struct intel_engine_cs *
i915_gem_object_last_write_engine(struct drm_i915_gem_object *obj)
{
          struct intel_engine_cs *engine = NULL;
          struct dma_fence *fence;

          rcu_read_lock();
          fence = reservation_object_get_excl_rcu(obj->resv);
          rcu_read_unlock();

          if (fence && dma_fence_is_i915(fence) && !dma_fence_is_signaled(fence))
                    engine = to_request(fence)->engine;
          dma_fence_put(fence);

          return engine;
}

void i915_gem_object_set_cache_coherency(struct drm_i915_gem_object *obj,
                                                   unsigned int cache_level);
void i915_gem_object_flush_if_display(struct drm_i915_gem_object *obj);

#endif