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, 671 insertions, 0 deletions

diff --git a/drivers/gpu/drm/vmwgfx/ttm_object.c b/drivers/gpu/drm/vmwgfx/ttm_object.c
new file mode 100644
index 000000000..ddf8373c1
--- /dev/null
+++ b/drivers/gpu/drm/vmwgfx/ttm_object.c
@@ -0,0 +1,671 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+/**************************************************************************
+ *
+ * Copyright (c) 2009-2022 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>
+ *
+ * While no substantial code is shared, the prime code is inspired by
+ * drm_prime.c, with
+ * Authors:
+ *      Dave Airlie <airlied@redhat.com>
+ *      Rob Clark <rob.clark@linaro.org>
+ */
+/** @file ttm_ref_object.c
+ *
+ * Base- and reference object implementation for the various
+ * ttm objects. Implements reference counting, minimal security checks
+ * and release on file close.
+ */
+
+
+#define pr_fmt(fmt) "[TTM] " fmt
+
+#include "ttm_object.h"
+#include "vmwgfx_drv.h"
+
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/atomic.h>
+#include <linux/module.h>
+#include <linux/hashtable.h>
+
+MODULE_IMPORT_NS(DMA_BUF);
+
+#define VMW_TTM_OBJECT_REF_HT_ORDER 10
+
+/**
+ * struct ttm_object_file
+ *
+ * @tdev: Pointer to the ttm_object_device.
+ *
+ * @lock: Lock that protects the ref_list list and the
+ * ref_hash hash tables.
+ *
+ * @ref_list: List of ttm_ref_objects to be destroyed at
+ * file release.
+ *
+ * @ref_hash: Hash tables of ref objects, one per ttm_ref_type,
+ * for fast lookup of ref objects given a base object.
+ *
+ * @refcount: reference/usage count
+ */
+struct ttm_object_file {
+	struct ttm_object_device *tdev;
+	spinlock_t lock;
+	struct list_head ref_list;
+	DECLARE_HASHTABLE(ref_hash, VMW_TTM_OBJECT_REF_HT_ORDER);
+	struct kref refcount;
+};
+
+/*
+ * struct ttm_object_device
+ *
+ * @object_lock: lock that protects idr.
+ *
+ * @object_count: Per device object count.
+ *
+ * This is the per-device data structure needed for ttm object management.
+ */
+
+struct ttm_object_device {
+	spinlock_t object_lock;
+	atomic_t object_count;
+	struct dma_buf_ops ops;
+	void (*dmabuf_release)(struct dma_buf *dma_buf);
+	struct idr idr;
+};
+
+/*
+ * struct ttm_ref_object
+ *
+ * @hash: Hash entry for the per-file object reference hash.
+ *
+ * @head: List entry for the per-file list of ref-objects.
+ *
+ * @kref: Ref count.
+ *
+ * @obj: Base object this ref object is referencing.
+ *
+ * @ref_type: Type of ref object.
+ *
+ * This is similar to an idr object, but it also has a hash table entry
+ * that allows lookup with a pointer to the referenced object as a key. In
+ * that way, one can easily detect whether a base object is referenced by
+ * a particular ttm_object_file. It also carries a ref count to avoid creating
+ * multiple ref objects if a ttm_object_file references the same base
+ * object more than once.
+ */
+
+struct ttm_ref_object {
+	struct rcu_head rcu_head;
+	struct vmwgfx_hash_item hash;
+	struct list_head head;
+	struct kref kref;
+	struct ttm_base_object *obj;
+	struct ttm_object_file *tfile;
+};
+
+static void ttm_prime_dmabuf_release(struct dma_buf *dma_buf);
+
+static inline struct ttm_object_file *
+ttm_object_file_ref(struct ttm_object_file *tfile)
+{
+	kref_get(&tfile->refcount);
+	return tfile;
+}
+
+static int ttm_tfile_find_ref_rcu(struct ttm_object_file *tfile,
+				  uint64_t key,
+				  struct vmwgfx_hash_item **p_hash)
+{
+	struct vmwgfx_hash_item *hash;
+
+	hash_for_each_possible_rcu(tfile->ref_hash, hash, head, key) {
+		if (hash->key == key) {
+			*p_hash = hash;
+			return 0;
+		}
+	}
+	return -EINVAL;
+}
+
+static int ttm_tfile_find_ref(struct ttm_object_file *tfile,
+			      uint64_t key,
+			      struct vmwgfx_hash_item **p_hash)
+{
+	struct vmwgfx_hash_item *hash;
+
+	hash_for_each_possible(tfile->ref_hash, hash, head, key) {
+		if (hash->key == key) {
+			*p_hash = hash;
+			return 0;
+		}
+	}
+	return -EINVAL;
+}
+
+static void ttm_object_file_destroy(struct kref *kref)
+{
+	struct ttm_object_file *tfile =
+		container_of(kref, struct ttm_object_file, refcount);
+
+	kfree(tfile);
+}
+
+
+static inline void ttm_object_file_unref(struct ttm_object_file **p_tfile)
+{
+	struct ttm_object_file *tfile = *p_tfile;
+
+	*p_tfile = NULL;
+	kref_put(&tfile->refcount, ttm_object_file_destroy);
+}
+
+
+int ttm_base_object_init(struct ttm_object_file *tfile,
+			 struct ttm_base_object *base,
+			 bool shareable,
+			 enum ttm_object_type object_type,
+			 void (*refcount_release) (struct ttm_base_object **))
+{
+	struct ttm_object_device *tdev = tfile->tdev;
+	int ret;
+
+	base->shareable = shareable;
+	base->tfile = ttm_object_file_ref(tfile);
+	base->refcount_release = refcount_release;
+	base->object_type = object_type;
+	kref_init(&base->refcount);
+	idr_preload(GFP_KERNEL);
+	spin_lock(&tdev->object_lock);
+	ret = idr_alloc(&tdev->idr, base, 1, 0, GFP_NOWAIT);
+	spin_unlock(&tdev->object_lock);
+	idr_preload_end();
+	if (ret < 0)
+		return ret;
+
+	base->handle = ret;
+	ret = ttm_ref_object_add(tfile, base, NULL, false);
+	if (unlikely(ret != 0))
+		goto out_err1;
+
+	ttm_base_object_unref(&base);
+
+	return 0;
+out_err1:
+	spin_lock(&tdev->object_lock);
+	idr_remove(&tdev->idr, base->handle);
+	spin_unlock(&tdev->object_lock);
+	return ret;
+}
+
+static void ttm_release_base(struct kref *kref)
+{
+	struct ttm_base_object *base =
+	    container_of(kref, struct ttm_base_object, refcount);
+	struct ttm_object_device *tdev = base->tfile->tdev;
+
+	spin_lock(&tdev->object_lock);
+	idr_remove(&tdev->idr, base->handle);
+	spin_unlock(&tdev->object_lock);
+
+	/*
+	 * Note: We don't use synchronize_rcu() here because it's far
+	 * too slow. It's up to the user to free the object using
+	 * call_rcu() or ttm_base_object_kfree().
+	 */
+
+	ttm_object_file_unref(&base->tfile);
+	if (base->refcount_release)
+		base->refcount_release(&base);
+}
+
+void ttm_base_object_unref(struct ttm_base_object **p_base)
+{
+	struct ttm_base_object *base = *p_base;
+
+	*p_base = NULL;
+
+	kref_put(&base->refcount, ttm_release_base);
+}
+
+struct ttm_base_object *ttm_base_object_lookup(struct ttm_object_file *tfile,
+					       uint64_t key)
+{
+	struct ttm_base_object *base = NULL;
+	struct vmwgfx_hash_item *hash;
+	int ret;
+
+	spin_lock(&tfile->lock);
+	ret = ttm_tfile_find_ref(tfile, key, &hash);
+
+	if (likely(ret == 0)) {
+		base = hlist_entry(hash, struct ttm_ref_object, hash)->obj;
+		if (!kref_get_unless_zero(&base->refcount))
+			base = NULL;
+	}
+	spin_unlock(&tfile->lock);
+
+
+	return base;
+}
+
+struct ttm_base_object *
+ttm_base_object_lookup_for_ref(struct ttm_object_device *tdev, uint64_t key)
+{
+	struct ttm_base_object *base;
+
+	rcu_read_lock();
+	base = idr_find(&tdev->idr, key);
+
+	if (base && !kref_get_unless_zero(&base->refcount))
+		base = NULL;
+	rcu_read_unlock();
+
+	return base;
+}
+
+int ttm_ref_object_add(struct ttm_object_file *tfile,
+		       struct ttm_base_object *base,
+		       bool *existed,
+		       bool require_existed)
+{
+	struct ttm_ref_object *ref;
+	struct vmwgfx_hash_item *hash;
+	int ret = -EINVAL;
+
+	if (base->tfile != tfile && !base->shareable)
+		return -EPERM;
+
+	if (existed != NULL)
+		*existed = true;
+
+	while (ret == -EINVAL) {
+		rcu_read_lock();
+		ret = ttm_tfile_find_ref_rcu(tfile, base->handle, &hash);
+
+		if (ret == 0) {
+			ref = hlist_entry(hash, struct ttm_ref_object, hash);
+			if (kref_get_unless_zero(&ref->kref)) {
+				rcu_read_unlock();
+				break;
+			}
+		}
+
+		rcu_read_unlock();
+		if (require_existed)
+			return -EPERM;
+
+		ref = kmalloc(sizeof(*ref), GFP_KERNEL);
+		if (unlikely(ref == NULL)) {
+			return -ENOMEM;
+		}
+
+		ref->hash.key = base->handle;
+		ref->obj = base;
+		ref->tfile = tfile;
+		kref_init(&ref->kref);
+
+		spin_lock(&tfile->lock);
+		hash_add_rcu(tfile->ref_hash, &ref->hash.head, ref->hash.key);
+		ret = 0;
+
+		list_add_tail(&ref->head, &tfile->ref_list);
+		kref_get(&base->refcount);
+		spin_unlock(&tfile->lock);
+		if (existed != NULL)
+			*existed = false;
+	}
+
+	return ret;
+}
+
+static void __releases(tfile->lock) __acquires(tfile->lock)
+ttm_ref_object_release(struct kref *kref)
+{
+	struct ttm_ref_object *ref =
+	    container_of(kref, struct ttm_ref_object, kref);
+	struct ttm_object_file *tfile = ref->tfile;
+
+	hash_del_rcu(&ref->hash.head);
+	list_del(&ref->head);
+	spin_unlock(&tfile->lock);
+
+	ttm_base_object_unref(&ref->obj);
+	kfree_rcu(ref, rcu_head);
+	spin_lock(&tfile->lock);
+}
+
+int ttm_ref_object_base_unref(struct ttm_object_file *tfile,
+			      unsigned long key)
+{
+	struct ttm_ref_object *ref;
+	struct vmwgfx_hash_item *hash;
+	int ret;
+
+	spin_lock(&tfile->lock);
+	ret = ttm_tfile_find_ref(tfile, key, &hash);
+	if (unlikely(ret != 0)) {
+		spin_unlock(&tfile->lock);
+		return -EINVAL;
+	}
+	ref = hlist_entry(hash, struct ttm_ref_object, hash);
+	kref_put(&ref->kref, ttm_ref_object_release);
+	spin_unlock(&tfile->lock);
+	return 0;
+}
+
+void ttm_object_file_release(struct ttm_object_file **p_tfile)
+{
+	struct ttm_ref_object *ref;
+	struct list_head *list;
+	struct ttm_object_file *tfile = *p_tfile;
+
+	*p_tfile = NULL;
+	spin_lock(&tfile->lock);
+
+	/*
+	 * Since we release the lock within the loop, we have to
+	 * restart it from the beginning each time.
+	 */
+
+	while (!list_empty(&tfile->ref_list)) {
+		list = tfile->ref_list.next;
+		ref = list_entry(list, struct ttm_ref_object, head);
+		ttm_ref_object_release(&ref->kref);
+	}
+
+	spin_unlock(&tfile->lock);
+
+	ttm_object_file_unref(&tfile);
+}
+
+struct ttm_object_file *ttm_object_file_init(struct ttm_object_device *tdev)
+{
+	struct ttm_object_file *tfile = kmalloc(sizeof(*tfile), GFP_KERNEL);
+
+	if (unlikely(tfile == NULL))
+		return NULL;
+
+	spin_lock_init(&tfile->lock);
+	tfile->tdev = tdev;
+	kref_init(&tfile->refcount);
+	INIT_LIST_HEAD(&tfile->ref_list);
+
+	hash_init(tfile->ref_hash);
+
+	return tfile;
+}
+
+struct ttm_object_device *
+ttm_object_device_init(const struct dma_buf_ops *ops)
+{
+	struct ttm_object_device *tdev = kmalloc(sizeof(*tdev), GFP_KERNEL);
+
+	if (unlikely(tdev == NULL))
+		return NULL;
+
+	spin_lock_init(&tdev->object_lock);
+	atomic_set(&tdev->object_count, 0);
+
+	/*
+	 * Our base is at VMWGFX_NUM_MOB + 1 because we want to create
+	 * a seperate namespace for GEM handles (which are
+	 * 1..VMWGFX_NUM_MOB) and the surface handles. Some ioctl's
+	 * can take either handle as an argument so we want to
+	 * easily be able to tell whether the handle refers to a
+	 * GEM buffer or a surface.
+	 */
+	idr_init_base(&tdev->idr, VMWGFX_NUM_MOB + 1);
+	tdev->ops = *ops;
+	tdev->dmabuf_release = tdev->ops.release;
+	tdev->ops.release = ttm_prime_dmabuf_release;
+	return tdev;
+}
+
+void ttm_object_device_release(struct ttm_object_device **p_tdev)
+{
+	struct ttm_object_device *tdev = *p_tdev;
+
+	*p_tdev = NULL;
+
+	WARN_ON_ONCE(!idr_is_empty(&tdev->idr));
+	idr_destroy(&tdev->idr);
+
+	kfree(tdev);
+}
+
+/**
+ * get_dma_buf_unless_doomed - get a dma_buf reference if possible.
+ *
+ * @dmabuf: Non-refcounted pointer to a struct dma-buf.
+ *
+ * Obtain a file reference from a lookup structure that doesn't refcount
+ * the file, but synchronizes with its release method to make sure it has
+ * not been freed yet. See for example kref_get_unless_zero documentation.
+ * Returns true if refcounting succeeds, false otherwise.
+ *
+ * Nobody really wants this as a public API yet, so let it mature here
+ * for some time...
+ */
+static bool __must_check get_dma_buf_unless_doomed(struct dma_buf *dmabuf)
+{
+	return atomic_long_inc_not_zero(&dmabuf->file->f_count) != 0L;
+}
+
+/**
+ * ttm_prime_refcount_release - refcount release method for a prime object.
+ *
+ * @p_base: Pointer to ttm_base_object pointer.
+ *
+ * This is a wrapper that calls the refcount_release founction of the
+ * underlying object. At the same time it cleans up the prime object.
+ * This function is called when all references to the base object we
+ * derive from are gone.
+ */
+static void ttm_prime_refcount_release(struct ttm_base_object **p_base)
+{
+	struct ttm_base_object *base = *p_base;
+	struct ttm_prime_object *prime;
+
+	*p_base = NULL;
+	prime = container_of(base, struct ttm_prime_object, base);
+	BUG_ON(prime->dma_buf != NULL);
+	mutex_destroy(&prime->mutex);
+	if (prime->refcount_release)
+		prime->refcount_release(&base);
+}
+
+/**
+ * ttm_prime_dmabuf_release - Release method for the dma-bufs we export
+ *
+ * @dma_buf:
+ *
+ * This function first calls the dma_buf release method the driver
+ * provides. Then it cleans up our dma_buf pointer used for lookup,
+ * and finally releases the reference the dma_buf has on our base
+ * object.
+ */
+static void ttm_prime_dmabuf_release(struct dma_buf *dma_buf)
+{
+	struct ttm_prime_object *prime =
+		(struct ttm_prime_object *) dma_buf->priv;
+	struct ttm_base_object *base = &prime->base;
+	struct ttm_object_device *tdev = base->tfile->tdev;
+
+	if (tdev->dmabuf_release)
+		tdev->dmabuf_release(dma_buf);
+	mutex_lock(&prime->mutex);
+	if (prime->dma_buf == dma_buf)
+		prime->dma_buf = NULL;
+	mutex_unlock(&prime->mutex);
+	ttm_base_object_unref(&base);
+}
+
+/**
+ * ttm_prime_fd_to_handle - Get a base object handle from a prime fd
+ *
+ * @tfile: A struct ttm_object_file identifying the caller.
+ * @fd: The prime / dmabuf fd.
+ * @handle: The returned handle.
+ *
+ * This function returns a handle to an object that previously exported
+ * a dma-buf. Note that we don't handle imports yet, because we simply
+ * have no consumers of that implementation.
+ */
+int ttm_prime_fd_to_handle(struct ttm_object_file *tfile,
+			   int fd, u32 *handle)
+{
+	struct ttm_object_device *tdev = tfile->tdev;
+	struct dma_buf *dma_buf;
+	struct ttm_prime_object *prime;
+	struct ttm_base_object *base;
+	int ret;
+
+	dma_buf = dma_buf_get(fd);
+	if (IS_ERR(dma_buf))
+		return PTR_ERR(dma_buf);
+
+	if (dma_buf->ops != &tdev->ops)
+		return -ENOSYS;
+
+	prime = (struct ttm_prime_object *) dma_buf->priv;
+	base = &prime->base;
+	*handle = base->handle;
+	ret = ttm_ref_object_add(tfile, base, NULL, false);
+
+	dma_buf_put(dma_buf);
+
+	return ret;
+}
+
+/**
+ * ttm_prime_handle_to_fd - Return a dma_buf fd from a ttm prime object
+ *
+ * @tfile: Struct ttm_object_file identifying the caller.
+ * @handle: Handle to the object we're exporting from.
+ * @flags: flags for dma-buf creation. We just pass them on.
+ * @prime_fd: The returned file descriptor.
+ *
+ */
+int ttm_prime_handle_to_fd(struct ttm_object_file *tfile,
+			   uint32_t handle, uint32_t flags,
+			   int *prime_fd)
+{
+	struct ttm_object_device *tdev = tfile->tdev;
+	struct ttm_base_object *base;
+	struct dma_buf *dma_buf;
+	struct ttm_prime_object *prime;
+	int ret;
+
+	base = ttm_base_object_lookup(tfile, handle);
+	if (unlikely(base == NULL ||
+		     base->object_type != ttm_prime_type)) {
+		ret = -ENOENT;
+		goto out_unref;
+	}
+
+	prime = container_of(base, struct ttm_prime_object, base);
+	if (unlikely(!base->shareable)) {
+		ret = -EPERM;
+		goto out_unref;
+	}
+
+	ret = mutex_lock_interruptible(&prime->mutex);
+	if (unlikely(ret != 0)) {
+		ret = -ERESTARTSYS;
+		goto out_unref;
+	}
+
+	dma_buf = prime->dma_buf;
+	if (!dma_buf || !get_dma_buf_unless_doomed(dma_buf)) {
+		DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+		exp_info.ops = &tdev->ops;
+		exp_info.size = prime->size;
+		exp_info.flags = flags;
+		exp_info.priv = prime;
+
+		/*
+		 * Need to create a new dma_buf
+		 */
+
+		dma_buf = dma_buf_export(&exp_info);
+		if (IS_ERR(dma_buf)) {
+			ret = PTR_ERR(dma_buf);
+			mutex_unlock(&prime->mutex);
+			goto out_unref;
+		}
+
+		/*
+		 * dma_buf has taken the base object reference
+		 */
+		base = NULL;
+		prime->dma_buf = dma_buf;
+	}
+	mutex_unlock(&prime->mutex);
+
+	ret = dma_buf_fd(dma_buf, flags);
+	if (ret >= 0) {
+		*prime_fd = ret;
+		ret = 0;
+	} else
+		dma_buf_put(dma_buf);
+
+out_unref:
+	if (base)
+		ttm_base_object_unref(&base);
+	return ret;
+}
+
+/**
+ * ttm_prime_object_init - Initialize a ttm_prime_object
+ *
+ * @tfile: struct ttm_object_file identifying the caller
+ * @size: The size of the dma_bufs we export.
+ * @prime: The object to be initialized.
+ * @shareable: See ttm_base_object_init
+ * @type: See ttm_base_object_init
+ * @refcount_release: See ttm_base_object_init
+ *
+ * Initializes an object which is compatible with the drm_prime model
+ * for data sharing between processes and devices.
+ */
+int ttm_prime_object_init(struct ttm_object_file *tfile, size_t size,
+			  struct ttm_prime_object *prime, bool shareable,
+			  enum ttm_object_type type,
+			  void (*refcount_release) (struct ttm_base_object **))
+{
+	mutex_init(&prime->mutex);
+	prime->size = PAGE_ALIGN(size);
+	prime->real_type = type;
+	prime->dma_buf = NULL;
+	prime->refcount_release = refcount_release;
+	return ttm_base_object_init(tfile, &prime->base, shareable,
+				    ttm_prime_type,
+				    ttm_prime_refcount_release);
+}