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, 475 insertions, 0 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
new file mode 100644
index 000000000..5a3e4b891
--- /dev/null
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -0,0 +1,475 @@
+/* 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_driver.h>
+#include <drm/ttm/ttm_placement.h>
+#include <drm/drm_vma_manager.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_managed.h>
+#include <linux/mm.h>
+#include <linux/pfn_t.h>
+#include <linux/rbtree.h>
+#include <linux/module.h>
+#include <linux/uaccess.h>
+#include <linux/mem_encrypt.h>
+
+static vm_fault_t ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo,
+				struct vm_fault *vmf)
+{
+	long err = 0;
+
+	/*
+	 * Quick non-stalling check for idle.
+	 */
+	if (dma_resv_test_signaled(bo->base.resv, DMA_RESV_USAGE_KERNEL))
+		return 0;
+
+	/*
+	 * If possible, avoid waiting for GPU with mmap_lock
+	 * held.  We only do this if the fault allows retry and this
+	 * is the first attempt.
+	 */
+	if (fault_flag_allow_retry_first(vmf->flags)) {
+		if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT)
+			return VM_FAULT_RETRY;
+
+		ttm_bo_get(bo);
+		mmap_read_unlock(vmf->vma->vm_mm);
+		(void)dma_resv_wait_timeout(bo->base.resv,
+					    DMA_RESV_USAGE_KERNEL, true,
+					    MAX_SCHEDULE_TIMEOUT);
+		dma_resv_unlock(bo->base.resv);
+		ttm_bo_put(bo);
+		return VM_FAULT_RETRY;
+	}
+
+	/*
+	 * Ordinary wait.
+	 */
+	err = dma_resv_wait_timeout(bo->base.resv, DMA_RESV_USAGE_KERNEL, true,
+				    MAX_SCHEDULE_TIMEOUT);
+	if (unlikely(err < 0)) {
+		return (err != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
+			VM_FAULT_NOPAGE;
+	}
+
+	return 0;
+}
+
+static unsigned long ttm_bo_io_mem_pfn(struct ttm_buffer_object *bo,
+				       unsigned long page_offset)
+{
+	struct ttm_device *bdev = bo->bdev;
+
+	if (bdev->funcs->io_mem_pfn)
+		return bdev->funcs->io_mem_pfn(bo, page_offset);
+
+	return (bo->resource->bus.offset >> PAGE_SHIFT) + page_offset;
+}
+
+/**
+ * ttm_bo_vm_reserve - Reserve a buffer object in a retryable vm callback
+ * @bo: The buffer object
+ * @vmf: The fault structure handed to the callback
+ *
+ * vm callbacks like fault() and *_mkwrite() allow for the mmap_lock to be dropped
+ * during long waits, and after the wait the callback will be restarted. This
+ * is to allow other threads using the same virtual memory space concurrent
+ * access to map(), unmap() completely unrelated buffer objects. TTM buffer
+ * object reservations sometimes wait for GPU and should therefore be
+ * considered long waits. This function reserves the buffer object interruptibly
+ * taking this into account. Starvation is avoided by the vm system not
+ * allowing too many repeated restarts.
+ * This function is intended to be used in customized fault() and _mkwrite()
+ * handlers.
+ *
+ * Return:
+ *    0 on success and the bo was reserved.
+ *    VM_FAULT_RETRY if blocking wait.
+ *    VM_FAULT_NOPAGE if blocking wait and retrying was not allowed.
+ */
+vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo,
+			     struct vm_fault *vmf)
+{
+	/*
+	 * Work around locking order reversal in fault / nopfn
+	 * between mmap_lock and bo_reserve: Perform a trylock operation
+	 * for reserve, and if it fails, retry the fault after waiting
+	 * for the buffer to become unreserved.
+	 */
+	if (unlikely(!dma_resv_trylock(bo->base.resv))) {
+		/*
+		 * If the fault allows retry and this is the first
+		 * fault attempt, we try to release the mmap_lock
+		 * before waiting
+		 */
+		if (fault_flag_allow_retry_first(vmf->flags)) {
+			if (!(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) {
+				ttm_bo_get(bo);
+				mmap_read_unlock(vmf->vma->vm_mm);
+				if (!dma_resv_lock_interruptible(bo->base.resv,
+								 NULL))
+					dma_resv_unlock(bo->base.resv);
+				ttm_bo_put(bo);
+			}
+
+			return VM_FAULT_RETRY;
+		}
+
+		if (dma_resv_lock_interruptible(bo->base.resv, NULL))
+			return VM_FAULT_NOPAGE;
+	}
+
+	/*
+	 * Refuse to fault imported pages. This should be handled
+	 * (if at all) by redirecting mmap to the exporter.
+	 */
+	if (bo->ttm && (bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL)) {
+		if (!(bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE)) {
+			dma_resv_unlock(bo->base.resv);
+			return VM_FAULT_SIGBUS;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(ttm_bo_vm_reserve);
+
+/**
+ * ttm_bo_vm_fault_reserved - TTM fault helper
+ * @vmf: The struct vm_fault given as argument to the fault callback
+ * @prot: The page protection to be used for this memory area.
+ * @num_prefault: Maximum number of prefault pages. The caller may want to
+ * specify this based on madvice settings and the size of the GPU object
+ * backed by the memory.
+ *
+ * This function inserts one or more page table entries pointing to the
+ * memory backing the buffer object, and then returns a return code
+ * instructing the caller to retry the page access.
+ *
+ * Return:
+ *   VM_FAULT_NOPAGE on success or pending signal
+ *   VM_FAULT_SIGBUS on unspecified error
+ *   VM_FAULT_OOM on out-of-memory
+ *   VM_FAULT_RETRY if retryable wait
+ */
+vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
+				    pgprot_t prot,
+				    pgoff_t num_prefault)
+{
+	struct vm_area_struct *vma = vmf->vma;
+	struct ttm_buffer_object *bo = vma->vm_private_data;
+	struct ttm_device *bdev = bo->bdev;
+	unsigned long page_offset;
+	unsigned long page_last;
+	unsigned long pfn;
+	struct ttm_tt *ttm = NULL;
+	struct page *page;
+	int err;
+	pgoff_t i;
+	vm_fault_t ret = VM_FAULT_NOPAGE;
+	unsigned long address = vmf->address;
+
+	/*
+	 * Wait for buffer data in transit, due to a pipelined
+	 * move.
+	 */
+	ret = ttm_bo_vm_fault_idle(bo, vmf);
+	if (unlikely(ret != 0))
+		return ret;
+
+	err = ttm_mem_io_reserve(bdev, bo->resource);
+	if (unlikely(err != 0))
+		return VM_FAULT_SIGBUS;
+
+	page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
+		vma->vm_pgoff - drm_vma_node_start(&bo->base.vma_node);
+	page_last = vma_pages(vma) + vma->vm_pgoff -
+		drm_vma_node_start(&bo->base.vma_node);
+
+	if (unlikely(page_offset >= PFN_UP(bo->base.size)))
+		return VM_FAULT_SIGBUS;
+
+	prot = ttm_io_prot(bo, bo->resource, prot);
+	if (!bo->resource->bus.is_iomem) {
+		struct ttm_operation_ctx ctx = {
+			.interruptible = false,
+			.no_wait_gpu = false,
+			.force_alloc = true
+		};
+
+		ttm = bo->ttm;
+		if (ttm_tt_populate(bdev, bo->ttm, &ctx))
+			return VM_FAULT_OOM;
+	} else {
+		/* Iomem should not be marked encrypted */
+		prot = pgprot_decrypted(prot);
+	}
+
+	/*
+	 * Speculatively prefault a number of pages. Only error on
+	 * first page.
+	 */
+	for (i = 0; i < num_prefault; ++i) {
+		if (bo->resource->bus.is_iomem) {
+			pfn = ttm_bo_io_mem_pfn(bo, page_offset);
+		} else {
+			page = ttm->pages[page_offset];
+			if (unlikely(!page && i == 0)) {
+				return VM_FAULT_OOM;
+			} else if (unlikely(!page)) {
+				break;
+			}
+			pfn = page_to_pfn(page);
+		}
+
+		/*
+		 * Note that the value of @prot at this point may differ from
+		 * the value of @vma->vm_page_prot in the caching- and
+		 * encryption bits. This is because the exact location of the
+		 * data may not be known at mmap() time and may also change
+		 * at arbitrary times while the data is mmap'ed.
+		 * See vmf_insert_mixed_prot() for a discussion.
+		 */
+		ret = vmf_insert_pfn_prot(vma, address, pfn, prot);
+
+		/* Never error on prefaulted PTEs */
+		if (unlikely((ret & VM_FAULT_ERROR))) {
+			if (i == 0)
+				return VM_FAULT_NOPAGE;
+			else
+				break;
+		}
+
+		address += PAGE_SIZE;
+		if (unlikely(++page_offset >= page_last))
+			break;
+	}
+	return ret;
+}
+EXPORT_SYMBOL(ttm_bo_vm_fault_reserved);
+
+static void ttm_bo_release_dummy_page(struct drm_device *dev, void *res)
+{
+	struct page *dummy_page = (struct page *)res;
+
+	__free_page(dummy_page);
+}
+
+vm_fault_t ttm_bo_vm_dummy_page(struct vm_fault *vmf, pgprot_t prot)
+{
+	struct vm_area_struct *vma = vmf->vma;
+	struct ttm_buffer_object *bo = vma->vm_private_data;
+	struct drm_device *ddev = bo->base.dev;
+	vm_fault_t ret = VM_FAULT_NOPAGE;
+	unsigned long address;
+	unsigned long pfn;
+	struct page *page;
+
+	/* Allocate new dummy page to map all the VA range in this VMA to it*/
+	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+	if (!page)
+		return VM_FAULT_OOM;
+
+	/* Set the page to be freed using drmm release action */
+	if (drmm_add_action_or_reset(ddev, ttm_bo_release_dummy_page, page))
+		return VM_FAULT_OOM;
+
+	pfn = page_to_pfn(page);
+
+	/* Prefault the entire VMA range right away to avoid further faults */
+	for (address = vma->vm_start; address < vma->vm_end;
+	     address += PAGE_SIZE)
+		ret = vmf_insert_pfn_prot(vma, address, pfn, prot);
+
+	return ret;
+}
+EXPORT_SYMBOL(ttm_bo_vm_dummy_page);
+
+vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf)
+{
+	struct vm_area_struct *vma = vmf->vma;
+	pgprot_t prot;
+	struct ttm_buffer_object *bo = vma->vm_private_data;
+	struct drm_device *ddev = bo->base.dev;
+	vm_fault_t ret;
+	int idx;
+
+	ret = ttm_bo_vm_reserve(bo, vmf);
+	if (ret)
+		return ret;
+
+	prot = vma->vm_page_prot;
+	if (drm_dev_enter(ddev, &idx)) {
+		ret = ttm_bo_vm_fault_reserved(vmf, prot, TTM_BO_VM_NUM_PREFAULT);
+		drm_dev_exit(idx);
+	} else {
+		ret = ttm_bo_vm_dummy_page(vmf, prot);
+	}
+	if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT))
+		return ret;
+
+	dma_resv_unlock(bo->base.resv);
+
+	return ret;
+}
+EXPORT_SYMBOL(ttm_bo_vm_fault);
+
+void ttm_bo_vm_open(struct vm_area_struct *vma)
+{
+	struct ttm_buffer_object *bo = vma->vm_private_data;
+
+	WARN_ON(bo->bdev->dev_mapping != vma->vm_file->f_mapping);
+
+	ttm_bo_get(bo);
+}
+EXPORT_SYMBOL(ttm_bo_vm_open);
+
+void ttm_bo_vm_close(struct vm_area_struct *vma)
+{
+	struct ttm_buffer_object *bo = vma->vm_private_data;
+
+	ttm_bo_put(bo);
+	vma->vm_private_data = NULL;
+}
+EXPORT_SYMBOL(ttm_bo_vm_close);
+
+static int ttm_bo_vm_access_kmap(struct ttm_buffer_object *bo,
+				 unsigned long offset,
+				 uint8_t *buf, int len, int write)
+{
+	unsigned long page = offset >> PAGE_SHIFT;
+	unsigned long bytes_left = len;
+	int ret;
+
+	/* Copy a page at a time, that way no extra virtual address
+	 * mapping is needed
+	 */
+	offset -= page << PAGE_SHIFT;
+	do {
+		unsigned long bytes = min(bytes_left, PAGE_SIZE - offset);
+		struct ttm_bo_kmap_obj map;
+		void *ptr;
+		bool is_iomem;
+
+		ret = ttm_bo_kmap(bo, page, 1, &map);
+		if (ret)
+			return ret;
+
+		ptr = (uint8_t *)ttm_kmap_obj_virtual(&map, &is_iomem) + offset;
+		WARN_ON_ONCE(is_iomem);
+		if (write)
+			memcpy(ptr, buf, bytes);
+		else
+			memcpy(buf, ptr, bytes);
+		ttm_bo_kunmap(&map);
+
+		page++;
+		buf += bytes;
+		bytes_left -= bytes;
+		offset = 0;
+	} while (bytes_left);
+
+	return len;
+}
+
+int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
+		     void *buf, int len, int write)
+{
+	struct ttm_buffer_object *bo = vma->vm_private_data;
+	unsigned long offset = (addr) - vma->vm_start +
+		((vma->vm_pgoff - drm_vma_node_start(&bo->base.vma_node))
+		 << PAGE_SHIFT);
+	int ret;
+
+	if (len < 1 || (offset + len) > bo->base.size)
+		return -EIO;
+
+	ret = ttm_bo_reserve(bo, true, false, NULL);
+	if (ret)
+		return ret;
+
+	switch (bo->resource->mem_type) {
+	case TTM_PL_SYSTEM:
+		fallthrough;
+	case TTM_PL_TT:
+		ret = ttm_bo_vm_access_kmap(bo, offset, buf, len, write);
+		break;
+	default:
+		if (bo->bdev->funcs->access_memory)
+			ret = bo->bdev->funcs->access_memory(
+				bo, offset, buf, len, write);
+		else
+			ret = -EIO;
+	}
+
+	ttm_bo_unreserve(bo);
+
+	return ret;
+}
+EXPORT_SYMBOL(ttm_bo_vm_access);
+
+static const struct vm_operations_struct ttm_bo_vm_ops = {
+	.fault = ttm_bo_vm_fault,
+	.open = ttm_bo_vm_open,
+	.close = ttm_bo_vm_close,
+	.access = ttm_bo_vm_access,
+};
+
+int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
+{
+	/* Enforce no COW since would have really strange behavior with it. */
+	if (is_cow_mapping(vma->vm_flags))
+		return -EINVAL;
+
+	ttm_bo_get(bo);
+
+	/*
+	 * Drivers may want to override the vm_ops field. Otherwise we
+	 * use TTM's default callbacks.
+	 */
+	if (!vma->vm_ops)
+		vma->vm_ops = &ttm_bo_vm_ops;
+
+	/*
+	 * Note: We're transferring the bo reference to
+	 * vma->vm_private_data here.
+	 */
+
+	vma->vm_private_data = bo;
+
+	vma->vm_flags |= VM_PFNMAP;
+	vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
+	return 0;
+}
+EXPORT_SYMBOL(ttm_bo_mmap_obj);