Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 705 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
new file mode 100644
index 000000000..f59f812dc
--- /dev/null
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
@@ -0,0 +1,705 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2021 Intel Corporation
+ */
+
+#include <drm/ttm/ttm_bo_driver.h>
+
+#include "i915_deps.h"
+#include "i915_drv.h"
+#include "intel_memory_region.h"
+#include "intel_region_ttm.h"
+
+#include "gem/i915_gem_object.h"
+#include "gem/i915_gem_region.h"
+#include "gem/i915_gem_ttm.h"
+#include "gem/i915_gem_ttm_move.h"
+
+#include "gt/intel_engine_pm.h"
+#include "gt/intel_gt.h"
+#include "gt/intel_migrate.h"
+
+/**
+ * DOC: Selftest failure modes for failsafe migration:
+ *
+ * For fail_gpu_migration, the gpu blit scheduled is always a clear blit
+ * rather than a copy blit, and then we force the failure paths as if
+ * the blit fence returned an error.
+ *
+ * For fail_work_allocation we fail the kmalloc of the async worker, we
+ * sync the gpu blit. If it then fails, or fail_gpu_migration is set to
+ * true, then a memcpy operation is performed sync.
+ */
+#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
+static bool fail_gpu_migration;
+static bool fail_work_allocation;
+static bool ban_memcpy;
+
+void i915_ttm_migrate_set_failure_modes(bool gpu_migration,
+					bool work_allocation)
+{
+	fail_gpu_migration = gpu_migration;
+	fail_work_allocation = work_allocation;
+}
+
+void i915_ttm_migrate_set_ban_memcpy(bool ban)
+{
+	ban_memcpy = ban;
+}
+#endif
+
+static enum i915_cache_level
+i915_ttm_cache_level(struct drm_i915_private *i915, struct ttm_resource *res,
+		     struct ttm_tt *ttm)
+{
+	return ((HAS_LLC(i915) || HAS_SNOOP(i915)) &&
+		!i915_ttm_gtt_binds_lmem(res) &&
+		ttm->caching == ttm_cached) ? I915_CACHE_LLC :
+		I915_CACHE_NONE;
+}
+
+static struct intel_memory_region *
+i915_ttm_region(struct ttm_device *bdev, int ttm_mem_type)
+{
+	struct drm_i915_private *i915 = container_of(bdev, typeof(*i915), bdev);
+
+	/* There's some room for optimization here... */
+	GEM_BUG_ON(ttm_mem_type != I915_PL_SYSTEM &&
+		   ttm_mem_type < I915_PL_LMEM0);
+	if (ttm_mem_type == I915_PL_SYSTEM)
+		return intel_memory_region_lookup(i915, INTEL_MEMORY_SYSTEM,
+						  0);
+
+	return intel_memory_region_lookup(i915, INTEL_MEMORY_LOCAL,
+					  ttm_mem_type - I915_PL_LMEM0);
+}
+
+/**
+ * i915_ttm_adjust_domains_after_move - Adjust the GEM domains after a
+ * TTM move
+ * @obj: The gem object
+ */
+void i915_ttm_adjust_domains_after_move(struct drm_i915_gem_object *obj)
+{
+	struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
+
+	if (i915_ttm_cpu_maps_iomem(bo->resource) || bo->ttm->caching != ttm_cached) {
+		obj->write_domain = I915_GEM_DOMAIN_WC;
+		obj->read_domains = I915_GEM_DOMAIN_WC;
+	} else {
+		obj->write_domain = I915_GEM_DOMAIN_CPU;
+		obj->read_domains = I915_GEM_DOMAIN_CPU;
+	}
+}
+
+/**
+ * i915_ttm_adjust_gem_after_move - Adjust the GEM state after a TTM move
+ * @obj: The gem object
+ *
+ * Adjusts the GEM object's region, mem_flags and cache coherency after a
+ * TTM move.
+ */
+void i915_ttm_adjust_gem_after_move(struct drm_i915_gem_object *obj)
+{
+	struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
+	unsigned int cache_level;
+	unsigned int i;
+
+	/*
+	 * If object was moved to an allowable region, update the object
+	 * region to consider it migrated. Note that if it's currently not
+	 * in an allowable region, it's evicted and we don't update the
+	 * object region.
+	 */
+	if (intel_region_to_ttm_type(obj->mm.region) != bo->resource->mem_type) {
+		for (i = 0; i < obj->mm.n_placements; ++i) {
+			struct intel_memory_region *mr = obj->mm.placements[i];
+
+			if (intel_region_to_ttm_type(mr) == bo->resource->mem_type &&
+			    mr != obj->mm.region) {
+				i915_gem_object_release_memory_region(obj);
+				i915_gem_object_init_memory_region(obj, mr);
+				break;
+			}
+		}
+	}
+
+	obj->mem_flags &= ~(I915_BO_FLAG_STRUCT_PAGE | I915_BO_FLAG_IOMEM);
+
+	obj->mem_flags |= i915_ttm_cpu_maps_iomem(bo->resource) ? I915_BO_FLAG_IOMEM :
+		I915_BO_FLAG_STRUCT_PAGE;
+
+	cache_level = i915_ttm_cache_level(to_i915(bo->base.dev), bo->resource,
+					   bo->ttm);
+	i915_gem_object_set_cache_coherency(obj, cache_level);
+}
+
+/**
+ * i915_ttm_move_notify - Prepare an object for move
+ * @bo: The ttm buffer object.
+ *
+ * This function prepares an object for move by removing all GPU bindings,
+ * removing all CPU mapings and finally releasing the pages sg-table.
+ *
+ * Return: 0 if successful, negative error code on error.
+ */
+int i915_ttm_move_notify(struct ttm_buffer_object *bo)
+{
+	struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
+	int ret;
+
+	/*
+	 * Note: The async unbinding here will actually transform the
+	 * blocking wait for unbind into a wait before finally submitting
+	 * evict / migration blit and thus stall the migration timeline
+	 * which may not be good for overall throughput. We should make
+	 * sure we await the unbind fences *after* the migration blit
+	 * instead of *before* as we currently do.
+	 */
+	ret = i915_gem_object_unbind(obj, I915_GEM_OBJECT_UNBIND_ACTIVE |
+				     I915_GEM_OBJECT_UNBIND_ASYNC);
+	if (ret)
+		return ret;
+
+	ret = __i915_gem_object_put_pages(obj);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static struct dma_fence *i915_ttm_accel_move(struct ttm_buffer_object *bo,
+					     bool clear,
+					     struct ttm_resource *dst_mem,
+					     struct ttm_tt *dst_ttm,
+					     struct sg_table *dst_st,
+					     const struct i915_deps *deps)
+{
+	struct drm_i915_private *i915 = container_of(bo->bdev, typeof(*i915),
+						     bdev);
+	struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
+	struct i915_request *rq;
+	struct ttm_tt *src_ttm = bo->ttm;
+	enum i915_cache_level src_level, dst_level;
+	int ret;
+
+	if (!to_gt(i915)->migrate.context || intel_gt_is_wedged(to_gt(i915)))
+		return ERR_PTR(-EINVAL);
+
+	/* With fail_gpu_migration, we always perform a GPU clear. */
+	if (I915_SELFTEST_ONLY(fail_gpu_migration))
+		clear = true;
+
+	dst_level = i915_ttm_cache_level(i915, dst_mem, dst_ttm);
+	if (clear) {
+		if (bo->type == ttm_bo_type_kernel &&
+		    !I915_SELFTEST_ONLY(fail_gpu_migration))
+			return ERR_PTR(-EINVAL);
+
+		intel_engine_pm_get(to_gt(i915)->migrate.context->engine);
+		ret = intel_context_migrate_clear(to_gt(i915)->migrate.context, deps,
+						  dst_st->sgl, dst_level,
+						  i915_ttm_gtt_binds_lmem(dst_mem),
+						  0, &rq);
+	} else {
+		struct i915_refct_sgt *src_rsgt =
+			i915_ttm_resource_get_st(obj, bo->resource);
+
+		if (IS_ERR(src_rsgt))
+			return ERR_CAST(src_rsgt);
+
+		src_level = i915_ttm_cache_level(i915, bo->resource, src_ttm);
+		intel_engine_pm_get(to_gt(i915)->migrate.context->engine);
+		ret = intel_context_migrate_copy(to_gt(i915)->migrate.context,
+						 deps, src_rsgt->table.sgl,
+						 src_level,
+						 i915_ttm_gtt_binds_lmem(bo->resource),
+						 dst_st->sgl, dst_level,
+						 i915_ttm_gtt_binds_lmem(dst_mem),
+						 &rq);
+
+		i915_refct_sgt_put(src_rsgt);
+	}
+
+	intel_engine_pm_put(to_gt(i915)->migrate.context->engine);
+
+	if (ret && rq) {
+		i915_request_wait(rq, 0, MAX_SCHEDULE_TIMEOUT);
+		i915_request_put(rq);
+	}
+
+	return ret ? ERR_PTR(ret) : &rq->fence;
+}
+
+/**
+ * struct i915_ttm_memcpy_arg - argument for the bo memcpy functionality.
+ * @_dst_iter: Storage space for the destination kmap iterator.
+ * @_src_iter: Storage space for the source kmap iterator.
+ * @dst_iter: Pointer to the destination kmap iterator.
+ * @src_iter: Pointer to the source kmap iterator.
+ * @clear: Whether to clear instead of copy.
+ * @src_rsgt: Refcounted scatter-gather list of source memory.
+ * @dst_rsgt: Refcounted scatter-gather list of destination memory.
+ */
+struct i915_ttm_memcpy_arg {
+	union {
+		struct ttm_kmap_iter_tt tt;
+		struct ttm_kmap_iter_iomap io;
+	} _dst_iter,
+	_src_iter;
+	struct ttm_kmap_iter *dst_iter;
+	struct ttm_kmap_iter *src_iter;
+	unsigned long num_pages;
+	bool clear;
+	struct i915_refct_sgt *src_rsgt;
+	struct i915_refct_sgt *dst_rsgt;
+};
+
+/**
+ * struct i915_ttm_memcpy_work - Async memcpy worker under a dma-fence.
+ * @fence: The dma-fence.
+ * @work: The work struct use for the memcpy work.
+ * @lock: The fence lock. Not used to protect anything else ATM.
+ * @irq_work: Low latency worker to signal the fence since it can't be done
+ * from the callback for lockdep reasons.
+ * @cb: Callback for the accelerated migration fence.
+ * @arg: The argument for the memcpy functionality.
+ * @i915: The i915 pointer.
+ * @obj: The GEM object.
+ * @memcpy_allowed: Instead of processing the @arg, and falling back to memcpy
+ * or memset, we wedge the device and set the @obj unknown_state, to prevent
+ * further access to the object with the CPU or GPU.  On some devices we might
+ * only be permitted to use the blitter engine for such operations.
+ */
+struct i915_ttm_memcpy_work {
+	struct dma_fence fence;
+	struct work_struct work;
+	spinlock_t lock;
+	struct irq_work irq_work;
+	struct dma_fence_cb cb;
+	struct i915_ttm_memcpy_arg arg;
+	struct drm_i915_private *i915;
+	struct drm_i915_gem_object *obj;
+	bool memcpy_allowed;
+};
+
+static void i915_ttm_move_memcpy(struct i915_ttm_memcpy_arg *arg)
+{
+	ttm_move_memcpy(arg->clear, arg->num_pages,
+			arg->dst_iter, arg->src_iter);
+}
+
+static void i915_ttm_memcpy_init(struct i915_ttm_memcpy_arg *arg,
+				 struct ttm_buffer_object *bo, bool clear,
+				 struct ttm_resource *dst_mem,
+				 struct ttm_tt *dst_ttm,
+				 struct i915_refct_sgt *dst_rsgt)
+{
+	struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
+	struct intel_memory_region *dst_reg, *src_reg;
+
+	dst_reg = i915_ttm_region(bo->bdev, dst_mem->mem_type);
+	src_reg = i915_ttm_region(bo->bdev, bo->resource->mem_type);
+	GEM_BUG_ON(!dst_reg || !src_reg);
+
+	arg->dst_iter = !i915_ttm_cpu_maps_iomem(dst_mem) ?
+		ttm_kmap_iter_tt_init(&arg->_dst_iter.tt, dst_ttm) :
+		ttm_kmap_iter_iomap_init(&arg->_dst_iter.io, &dst_reg->iomap,
+					 &dst_rsgt->table, dst_reg->region.start);
+
+	arg->src_iter = !i915_ttm_cpu_maps_iomem(bo->resource) ?
+		ttm_kmap_iter_tt_init(&arg->_src_iter.tt, bo->ttm) :
+		ttm_kmap_iter_iomap_init(&arg->_src_iter.io, &src_reg->iomap,
+					 &obj->ttm.cached_io_rsgt->table,
+					 src_reg->region.start);
+	arg->clear = clear;
+	arg->num_pages = bo->base.size >> PAGE_SHIFT;
+
+	arg->dst_rsgt = i915_refct_sgt_get(dst_rsgt);
+	arg->src_rsgt = clear ? NULL :
+		i915_ttm_resource_get_st(obj, bo->resource);
+}
+
+static void i915_ttm_memcpy_release(struct i915_ttm_memcpy_arg *arg)
+{
+	i915_refct_sgt_put(arg->src_rsgt);
+	i915_refct_sgt_put(arg->dst_rsgt);
+}
+
+static void __memcpy_work(struct work_struct *work)
+{
+	struct i915_ttm_memcpy_work *copy_work =
+		container_of(work, typeof(*copy_work), work);
+	struct i915_ttm_memcpy_arg *arg = &copy_work->arg;
+	bool cookie;
+
+	/*
+	 * FIXME: We need to take a closer look here. We should be able to plonk
+	 * this into the fence critical section.
+	 */
+	if (!copy_work->memcpy_allowed) {
+		struct intel_gt *gt;
+		unsigned int id;
+
+		for_each_gt(gt, copy_work->i915, id)
+			intel_gt_set_wedged(gt);
+	}
+
+	cookie = dma_fence_begin_signalling();
+
+	if (copy_work->memcpy_allowed) {
+		i915_ttm_move_memcpy(arg);
+	} else {
+		/*
+		 * Prevent further use of the object. Any future GTT binding or
+		 * CPU access is not allowed once we signal the fence. Outside
+		 * of the fence critical section, we then also then wedge the gpu
+		 * to indicate the device is not functional.
+		 *
+		 * The below dma_fence_signal() is our write-memory-barrier.
+		 */
+		copy_work->obj->mm.unknown_state = true;
+	}
+
+	dma_fence_end_signalling(cookie);
+
+	dma_fence_signal(&copy_work->fence);
+
+	i915_ttm_memcpy_release(arg);
+	i915_gem_object_put(copy_work->obj);
+	dma_fence_put(&copy_work->fence);
+}
+
+static void __memcpy_irq_work(struct irq_work *irq_work)
+{
+	struct i915_ttm_memcpy_work *copy_work =
+		container_of(irq_work, typeof(*copy_work), irq_work);
+	struct i915_ttm_memcpy_arg *arg = &copy_work->arg;
+
+	dma_fence_signal(&copy_work->fence);
+	i915_ttm_memcpy_release(arg);
+	i915_gem_object_put(copy_work->obj);
+	dma_fence_put(&copy_work->fence);
+}
+
+static void __memcpy_cb(struct dma_fence *fence, struct dma_fence_cb *cb)
+{
+	struct i915_ttm_memcpy_work *copy_work =
+		container_of(cb, typeof(*copy_work), cb);
+
+	if (unlikely(fence->error || I915_SELFTEST_ONLY(fail_gpu_migration))) {
+		INIT_WORK(&copy_work->work, __memcpy_work);
+		queue_work(system_unbound_wq, &copy_work->work);
+	} else {
+		init_irq_work(&copy_work->irq_work, __memcpy_irq_work);
+		irq_work_queue(&copy_work->irq_work);
+	}
+}
+
+static const char *get_driver_name(struct dma_fence *fence)
+{
+	return "i915_ttm_memcpy_work";
+}
+
+static const char *get_timeline_name(struct dma_fence *fence)
+{
+	return "unbound";
+}
+
+static const struct dma_fence_ops dma_fence_memcpy_ops = {
+	.get_driver_name = get_driver_name,
+	.get_timeline_name = get_timeline_name,
+};
+
+static struct dma_fence *
+i915_ttm_memcpy_work_arm(struct i915_ttm_memcpy_work *work,
+			 struct dma_fence *dep)
+{
+	int ret;
+
+	spin_lock_init(&work->lock);
+	dma_fence_init(&work->fence, &dma_fence_memcpy_ops, &work->lock, 0, 0);
+	dma_fence_get(&work->fence);
+	ret = dma_fence_add_callback(dep, &work->cb, __memcpy_cb);
+	if (ret) {
+		if (ret != -ENOENT)
+			dma_fence_wait(dep, false);
+
+		return ERR_PTR(I915_SELFTEST_ONLY(fail_gpu_migration) ? -EINVAL :
+			       dep->error);
+	}
+
+	return &work->fence;
+}
+
+static bool i915_ttm_memcpy_allowed(struct ttm_buffer_object *bo,
+				    struct ttm_resource *dst_mem)
+{
+	if (i915_gem_object_needs_ccs_pages(i915_ttm_to_gem(bo)))
+		return false;
+
+	if (!(i915_ttm_resource_mappable(bo->resource) &&
+	      i915_ttm_resource_mappable(dst_mem)))
+		return false;
+
+	return I915_SELFTEST_ONLY(ban_memcpy) ? false : true;
+}
+
+static struct dma_fence *
+__i915_ttm_move(struct ttm_buffer_object *bo,
+		const struct ttm_operation_ctx *ctx, bool clear,
+		struct ttm_resource *dst_mem, struct ttm_tt *dst_ttm,
+		struct i915_refct_sgt *dst_rsgt, bool allow_accel,
+		const struct i915_deps *move_deps)
+{
+	const bool memcpy_allowed = i915_ttm_memcpy_allowed(bo, dst_mem);
+	struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
+	struct drm_i915_private *i915 = to_i915(bo->base.dev);
+	struct i915_ttm_memcpy_work *copy_work = NULL;
+	struct i915_ttm_memcpy_arg _arg, *arg = &_arg;
+	struct dma_fence *fence = ERR_PTR(-EINVAL);
+
+	if (allow_accel) {
+		fence = i915_ttm_accel_move(bo, clear, dst_mem, dst_ttm,
+					    &dst_rsgt->table, move_deps);
+
+		/*
+		 * We only need to intercept the error when moving to lmem.
+		 * When moving to system, TTM or shmem will provide us with
+		 * cleared pages.
+		 */
+		if (!IS_ERR(fence) && !i915_ttm_gtt_binds_lmem(dst_mem) &&
+		    !I915_SELFTEST_ONLY(fail_gpu_migration ||
+					fail_work_allocation))
+			goto out;
+	}
+
+	/* If we've scheduled gpu migration. Try to arm error intercept. */
+	if (!IS_ERR(fence)) {
+		struct dma_fence *dep = fence;
+
+		if (!I915_SELFTEST_ONLY(fail_work_allocation))
+			copy_work = kzalloc(sizeof(*copy_work), GFP_KERNEL);
+
+		if (copy_work) {
+			copy_work->i915 = i915;
+			copy_work->memcpy_allowed = memcpy_allowed;
+			copy_work->obj = i915_gem_object_get(obj);
+			arg = &copy_work->arg;
+			if (memcpy_allowed)
+				i915_ttm_memcpy_init(arg, bo, clear, dst_mem,
+						     dst_ttm, dst_rsgt);
+
+			fence = i915_ttm_memcpy_work_arm(copy_work, dep);
+		} else {
+			dma_fence_wait(dep, false);
+			fence = ERR_PTR(I915_SELFTEST_ONLY(fail_gpu_migration) ?
+					-EINVAL : fence->error);
+		}
+		dma_fence_put(dep);
+
+		if (!IS_ERR(fence))
+			goto out;
+	} else {
+		int err = PTR_ERR(fence);
+
+		if (err == -EINTR || err == -ERESTARTSYS || err == -EAGAIN)
+			return fence;
+
+		if (move_deps) {
+			err = i915_deps_sync(move_deps, ctx);
+			if (err)
+				return ERR_PTR(err);
+		}
+	}
+
+	/* Error intercept failed or no accelerated migration to start with */
+
+	if (memcpy_allowed) {
+		if (!copy_work)
+			i915_ttm_memcpy_init(arg, bo, clear, dst_mem, dst_ttm,
+					     dst_rsgt);
+		i915_ttm_move_memcpy(arg);
+		i915_ttm_memcpy_release(arg);
+	}
+	if (copy_work)
+		i915_gem_object_put(copy_work->obj);
+	kfree(copy_work);
+
+	return memcpy_allowed ? NULL : ERR_PTR(-EIO);
+out:
+	if (!fence && copy_work) {
+		i915_ttm_memcpy_release(arg);
+		i915_gem_object_put(copy_work->obj);
+		kfree(copy_work);
+	}
+
+	return fence;
+}
+
+/**
+ * i915_ttm_move - The TTM move callback used by i915.
+ * @bo: The buffer object.
+ * @evict: Whether this is an eviction.
+ * @dst_mem: The destination ttm resource.
+ * @hop: If we need multihop, what temporary memory type to move to.
+ *
+ * Return: 0 if successful, negative error code otherwise.
+ */
+int i915_ttm_move(struct ttm_buffer_object *bo, bool evict,
+		  struct ttm_operation_ctx *ctx,
+		  struct ttm_resource *dst_mem,
+		  struct ttm_place *hop)
+{
+	struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
+	struct ttm_resource_manager *dst_man =
+		ttm_manager_type(bo->bdev, dst_mem->mem_type);
+	struct dma_fence *migration_fence = NULL;
+	struct ttm_tt *ttm = bo->ttm;
+	struct i915_refct_sgt *dst_rsgt;
+	bool clear;
+	int ret;
+
+	if (GEM_WARN_ON(i915_ttm_is_ghost_object(bo))) {
+		ttm_bo_move_null(bo, dst_mem);
+		return 0;
+	}
+
+	ret = i915_ttm_move_notify(bo);
+	if (ret)
+		return ret;
+
+	if (obj->mm.madv != I915_MADV_WILLNEED) {
+		i915_ttm_purge(obj);
+		ttm_resource_free(bo, &dst_mem);
+		return 0;
+	}
+
+	/* Populate ttm with pages if needed. Typically system memory. */
+	if (ttm && (dst_man->use_tt || (ttm->page_flags & TTM_TT_FLAG_SWAPPED))) {
+		ret = ttm_tt_populate(bo->bdev, ttm, ctx);
+		if (ret)
+			return ret;
+	}
+
+	dst_rsgt = i915_ttm_resource_get_st(obj, dst_mem);
+	if (IS_ERR(dst_rsgt))
+		return PTR_ERR(dst_rsgt);
+
+	clear = !i915_ttm_cpu_maps_iomem(bo->resource) && (!ttm || !ttm_tt_is_populated(ttm));
+	if (!(clear && ttm && !(ttm->page_flags & TTM_TT_FLAG_ZERO_ALLOC))) {
+		struct i915_deps deps;
+
+		i915_deps_init(&deps, GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
+		ret = i915_deps_add_resv(&deps, bo->base.resv, ctx);
+		if (ret) {
+			i915_refct_sgt_put(dst_rsgt);
+			return ret;
+		}
+
+		migration_fence = __i915_ttm_move(bo, ctx, clear, dst_mem, ttm,
+						  dst_rsgt, true, &deps);
+		i915_deps_fini(&deps);
+	}
+
+	/* We can possibly get an -ERESTARTSYS here */
+	if (IS_ERR(migration_fence)) {
+		i915_refct_sgt_put(dst_rsgt);
+		return PTR_ERR(migration_fence);
+	}
+
+	if (migration_fence) {
+		if (I915_SELFTEST_ONLY(evict && fail_gpu_migration))
+			ret = -EIO; /* never feed non-migrate fences into ttm */
+		else
+			ret = ttm_bo_move_accel_cleanup(bo, migration_fence, evict,
+							true, dst_mem);
+		if (ret) {
+			dma_fence_wait(migration_fence, false);
+			ttm_bo_move_sync_cleanup(bo, dst_mem);
+		}
+		dma_fence_put(migration_fence);
+	} else {
+		ttm_bo_move_sync_cleanup(bo, dst_mem);
+	}
+
+	i915_ttm_adjust_domains_after_move(obj);
+	i915_ttm_free_cached_io_rsgt(obj);
+
+	if (i915_ttm_gtt_binds_lmem(dst_mem) || i915_ttm_cpu_maps_iomem(dst_mem)) {
+		obj->ttm.cached_io_rsgt = dst_rsgt;
+		obj->ttm.get_io_page.sg_pos = dst_rsgt->table.sgl;
+		obj->ttm.get_io_page.sg_idx = 0;
+	} else {
+		i915_refct_sgt_put(dst_rsgt);
+	}
+
+	i915_ttm_adjust_lru(obj);
+	i915_ttm_adjust_gem_after_move(obj);
+	return 0;
+}
+
+/**
+ * i915_gem_obj_copy_ttm - Copy the contents of one ttm-based gem object to
+ * another
+ * @dst: The destination object
+ * @src: The source object
+ * @allow_accel: Allow using the blitter. Otherwise TTM memcpy is used.
+ * @intr: Whether to perform waits interruptible:
+ *
+ * Note: The caller is responsible for assuring that the underlying
+ * TTM objects are populated if needed and locked.
+ *
+ * Return: Zero on success. Negative error code on error. If @intr == true,
+ * then it may return -ERESTARTSYS or -EINTR.
+ */
+int i915_gem_obj_copy_ttm(struct drm_i915_gem_object *dst,
+			  struct drm_i915_gem_object *src,
+			  bool allow_accel, bool intr)
+{
+	struct ttm_buffer_object *dst_bo = i915_gem_to_ttm(dst);
+	struct ttm_buffer_object *src_bo = i915_gem_to_ttm(src);
+	struct ttm_operation_ctx ctx = {
+		.interruptible = intr,
+	};
+	struct i915_refct_sgt *dst_rsgt;
+	struct dma_fence *copy_fence;
+	struct i915_deps deps;
+	int ret;
+
+	assert_object_held(dst);
+	assert_object_held(src);
+	i915_deps_init(&deps, GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
+
+	ret = dma_resv_reserve_fences(src_bo->base.resv, 1);
+	if (ret)
+		return ret;
+
+	ret = dma_resv_reserve_fences(dst_bo->base.resv, 1);
+	if (ret)
+		return ret;
+
+	ret = i915_deps_add_resv(&deps, dst_bo->base.resv, &ctx);
+	if (ret)
+		return ret;
+
+	ret = i915_deps_add_resv(&deps, src_bo->base.resv, &ctx);
+	if (ret)
+		return ret;
+
+	dst_rsgt = i915_ttm_resource_get_st(dst, dst_bo->resource);
+	copy_fence = __i915_ttm_move(src_bo, &ctx, false, dst_bo->resource,
+				     dst_bo->ttm, dst_rsgt, allow_accel,
+				     &deps);
+
+	i915_deps_fini(&deps);
+	i915_refct_sgt_put(dst_rsgt);
+	if (IS_ERR_OR_NULL(copy_fence))
+		return PTR_ERR_OR_ZERO(copy_fence);
+
+	dma_resv_add_fence(dst_bo->base.resv, copy_fence, DMA_RESV_USAGE_WRITE);
+	dma_resv_add_fence(src_bo->base.resv, copy_fence, DMA_RESV_USAGE_READ);
+	dma_fence_put(copy_fence);
+
+	return 0;
+}