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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/gpu/drm/i915/i915_gem_evict.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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(). ...
Diffstat (limited to 'drivers/gpu/drm/i915/i915_gem_evict.c')
-rw-r--r--drivers/gpu/drm/i915/i915_gem_evict.c520
1 files changed, 520 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c
new file mode 100644
index 000000000..a4b4d9b7d
--- /dev/null
+++ b/drivers/gpu/drm/i915/i915_gem_evict.c
@@ -0,0 +1,520 @@
+/*
+ * Copyright © 2008-2010 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.
+ *
+ * Authors:
+ * Eric Anholt <eric@anholt.net>
+ * Chris Wilson <chris@chris-wilson.co.uuk>
+ *
+ */
+
+#include "gem/i915_gem_context.h"
+#include "gt/intel_gt.h"
+#include "gt/intel_gt_requests.h"
+
+#include "i915_drv.h"
+#include "i915_gem_evict.h"
+#include "i915_trace.h"
+
+I915_SELFTEST_DECLARE(static struct igt_evict_ctl {
+ bool fail_if_busy:1;
+} igt_evict_ctl;)
+
+static bool dying_vma(struct i915_vma *vma)
+{
+ return !kref_read(&vma->obj->base.refcount);
+}
+
+static int ggtt_flush(struct intel_gt *gt)
+{
+ /*
+ * Not everything in the GGTT is tracked via vma (otherwise we
+ * could evict as required with minimal stalling) so we are forced
+ * to idle the GPU and explicitly retire outstanding requests in
+ * the hopes that we can then remove contexts and the like only
+ * bound by their active reference.
+ */
+ return intel_gt_wait_for_idle(gt, MAX_SCHEDULE_TIMEOUT);
+}
+
+static bool grab_vma(struct i915_vma *vma, struct i915_gem_ww_ctx *ww)
+{
+ /*
+ * We add the extra refcount so the object doesn't drop to zero until
+ * after ungrab_vma(), this way trylock is always paired with unlock.
+ */
+ if (i915_gem_object_get_rcu(vma->obj)) {
+ if (!i915_gem_object_trylock(vma->obj, ww)) {
+ i915_gem_object_put(vma->obj);
+ return false;
+ }
+ } else {
+ /* Dead objects don't need pins */
+ atomic_and(~I915_VMA_PIN_MASK, &vma->flags);
+ }
+
+ return true;
+}
+
+static void ungrab_vma(struct i915_vma *vma)
+{
+ if (dying_vma(vma))
+ return;
+
+ i915_gem_object_unlock(vma->obj);
+ i915_gem_object_put(vma->obj);
+}
+
+static bool
+mark_free(struct drm_mm_scan *scan,
+ struct i915_gem_ww_ctx *ww,
+ struct i915_vma *vma,
+ unsigned int flags,
+ struct list_head *unwind)
+{
+ if (i915_vma_is_pinned(vma))
+ return false;
+
+ if (!grab_vma(vma, ww))
+ return false;
+
+ list_add(&vma->evict_link, unwind);
+ return drm_mm_scan_add_block(scan, &vma->node);
+}
+
+static bool defer_evict(struct i915_vma *vma)
+{
+ if (i915_vma_is_active(vma))
+ return true;
+
+ if (i915_vma_is_scanout(vma))
+ return true;
+
+ return false;
+}
+
+/**
+ * i915_gem_evict_something - Evict vmas to make room for binding a new one
+ * @vm: address space to evict from
+ * @ww: An optional struct i915_gem_ww_ctx.
+ * @min_size: size of the desired free space
+ * @alignment: alignment constraint of the desired free space
+ * @color: color for the desired space
+ * @start: start (inclusive) of the range from which to evict objects
+ * @end: end (exclusive) of the range from which to evict objects
+ * @flags: additional flags to control the eviction algorithm
+ *
+ * This function will try to evict vmas until a free space satisfying the
+ * requirements is found. Callers must check first whether any such hole exists
+ * already before calling this function.
+ *
+ * This function is used by the object/vma binding code.
+ *
+ * Since this function is only used to free up virtual address space it only
+ * ignores pinned vmas, and not object where the backing storage itself is
+ * pinned. Hence obj->pages_pin_count does not protect against eviction.
+ *
+ * To clarify: This is for freeing up virtual address space, not for freeing
+ * memory in e.g. the shrinker.
+ */
+int
+i915_gem_evict_something(struct i915_address_space *vm,
+ struct i915_gem_ww_ctx *ww,
+ u64 min_size, u64 alignment,
+ unsigned long color,
+ u64 start, u64 end,
+ unsigned flags)
+{
+ struct drm_mm_scan scan;
+ struct list_head eviction_list;
+ struct i915_vma *vma, *next;
+ struct drm_mm_node *node;
+ enum drm_mm_insert_mode mode;
+ struct i915_vma *active;
+ int ret;
+
+ lockdep_assert_held(&vm->mutex);
+ trace_i915_gem_evict(vm, min_size, alignment, flags);
+
+ /*
+ * The goal is to evict objects and amalgamate space in rough LRU order.
+ * Since both active and inactive objects reside on the same list,
+ * in a mix of creation and last scanned order, as we process the list
+ * we sort it into inactive/active, which keeps the active portion
+ * in a rough MRU order.
+ *
+ * The retirement sequence is thus:
+ * 1. Inactive objects (already retired, random order)
+ * 2. Active objects (will stall on unbinding, oldest scanned first)
+ */
+ mode = DRM_MM_INSERT_BEST;
+ if (flags & PIN_HIGH)
+ mode = DRM_MM_INSERT_HIGH;
+ if (flags & PIN_MAPPABLE)
+ mode = DRM_MM_INSERT_LOW;
+ drm_mm_scan_init_with_range(&scan, &vm->mm,
+ min_size, alignment, color,
+ start, end, mode);
+
+ intel_gt_retire_requests(vm->gt);
+
+search_again:
+ active = NULL;
+ INIT_LIST_HEAD(&eviction_list);
+ list_for_each_entry_safe(vma, next, &vm->bound_list, vm_link) {
+ if (vma == active) { /* now seen this vma twice */
+ if (flags & PIN_NONBLOCK)
+ break;
+
+ active = ERR_PTR(-EAGAIN);
+ }
+
+ /*
+ * We keep this list in a rough least-recently scanned order
+ * of active elements (inactive elements are cheap to reap).
+ * New entries are added to the end, and we move anything we
+ * scan to the end. The assumption is that the working set
+ * of applications is either steady state (and thanks to the
+ * userspace bo cache it almost always is) or volatile and
+ * frequently replaced after a frame, which are self-evicting!
+ * Given that assumption, the MRU order of the scan list is
+ * fairly static, and keeping it in least-recently scan order
+ * is suitable.
+ *
+ * To notice when we complete one full cycle, we record the
+ * first active element seen, before moving it to the tail.
+ */
+ if (active != ERR_PTR(-EAGAIN) && defer_evict(vma)) {
+ if (!active)
+ active = vma;
+
+ list_move_tail(&vma->vm_link, &vm->bound_list);
+ continue;
+ }
+
+ if (mark_free(&scan, ww, vma, flags, &eviction_list))
+ goto found;
+ }
+
+ /* Nothing found, clean up and bail out! */
+ list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
+ ret = drm_mm_scan_remove_block(&scan, &vma->node);
+ BUG_ON(ret);
+ ungrab_vma(vma);
+ }
+
+ /*
+ * Can we unpin some objects such as idle hw contents,
+ * or pending flips? But since only the GGTT has global entries
+ * such as scanouts, rinbuffers and contexts, we can skip the
+ * purge when inspecting per-process local address spaces.
+ */
+ if (!i915_is_ggtt(vm) || flags & PIN_NONBLOCK)
+ return -ENOSPC;
+
+ /*
+ * Not everything in the GGTT is tracked via VMA using
+ * i915_vma_move_to_active(), otherwise we could evict as required
+ * with minimal stalling. Instead we are forced to idle the GPU and
+ * explicitly retire outstanding requests which will then remove
+ * the pinning for active objects such as contexts and ring,
+ * enabling us to evict them on the next iteration.
+ *
+ * To ensure that all user contexts are evictable, we perform
+ * a switch to the perma-pinned kernel context. This all also gives
+ * us a termination condition, when the last retired context is
+ * the kernel's there is no more we can evict.
+ */
+ if (I915_SELFTEST_ONLY(igt_evict_ctl.fail_if_busy))
+ return -EBUSY;
+
+ ret = ggtt_flush(vm->gt);
+ if (ret)
+ return ret;
+
+ cond_resched();
+
+ flags |= PIN_NONBLOCK;
+ goto search_again;
+
+found:
+ /* drm_mm doesn't allow any other other operations while
+ * scanning, therefore store to-be-evicted objects on a
+ * temporary list and take a reference for all before
+ * calling unbind (which may remove the active reference
+ * of any of our objects, thus corrupting the list).
+ */
+ list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
+ if (drm_mm_scan_remove_block(&scan, &vma->node)) {
+ __i915_vma_pin(vma);
+ } else {
+ list_del(&vma->evict_link);
+ ungrab_vma(vma);
+ }
+ }
+
+ /* Unbinding will emit any required flushes */
+ ret = 0;
+ list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
+ __i915_vma_unpin(vma);
+ if (ret == 0)
+ ret = __i915_vma_unbind(vma);
+ ungrab_vma(vma);
+ }
+
+ while (ret == 0 && (node = drm_mm_scan_color_evict(&scan))) {
+ vma = container_of(node, struct i915_vma, node);
+
+ /* If we find any non-objects (!vma), we cannot evict them */
+ if (vma->node.color != I915_COLOR_UNEVICTABLE &&
+ grab_vma(vma, ww)) {
+ ret = __i915_vma_unbind(vma);
+ ungrab_vma(vma);
+ } else {
+ ret = -ENOSPC;
+ }
+ }
+
+ return ret;
+}
+
+/**
+ * i915_gem_evict_for_node - Evict vmas to make room for binding a new one
+ * @vm: address space to evict from
+ * @ww: An optional struct i915_gem_ww_ctx.
+ * @target: range (and color) to evict for
+ * @flags: additional flags to control the eviction algorithm
+ *
+ * This function will try to evict vmas that overlap the target node.
+ *
+ * To clarify: This is for freeing up virtual address space, not for freeing
+ * memory in e.g. the shrinker.
+ */
+int i915_gem_evict_for_node(struct i915_address_space *vm,
+ struct i915_gem_ww_ctx *ww,
+ struct drm_mm_node *target,
+ unsigned int flags)
+{
+ LIST_HEAD(eviction_list);
+ struct drm_mm_node *node;
+ u64 start = target->start;
+ u64 end = start + target->size;
+ struct i915_vma *vma, *next;
+ int ret = 0;
+
+ lockdep_assert_held(&vm->mutex);
+ GEM_BUG_ON(!IS_ALIGNED(start, I915_GTT_PAGE_SIZE));
+ GEM_BUG_ON(!IS_ALIGNED(end, I915_GTT_PAGE_SIZE));
+
+ trace_i915_gem_evict_node(vm, target, flags);
+
+ /*
+ * Retire before we search the active list. Although we have
+ * reasonable accuracy in our retirement lists, we may have
+ * a stray pin (preventing eviction) that can only be resolved by
+ * retiring.
+ */
+ intel_gt_retire_requests(vm->gt);
+
+ if (i915_vm_has_cache_coloring(vm)) {
+ /* Expand search to cover neighbouring guard pages (or lack!) */
+ if (start)
+ start -= I915_GTT_PAGE_SIZE;
+
+ /* Always look at the page afterwards to avoid the end-of-GTT */
+ end += I915_GTT_PAGE_SIZE;
+ }
+ GEM_BUG_ON(start >= end);
+
+ drm_mm_for_each_node_in_range(node, &vm->mm, start, end) {
+ /* If we find any non-objects (!vma), we cannot evict them */
+ if (node->color == I915_COLOR_UNEVICTABLE) {
+ ret = -ENOSPC;
+ break;
+ }
+
+ GEM_BUG_ON(!drm_mm_node_allocated(node));
+ vma = container_of(node, typeof(*vma), node);
+
+ /*
+ * If we are using coloring to insert guard pages between
+ * different cache domains within the address space, we have
+ * to check whether the objects on either side of our range
+ * abutt and conflict. If they are in conflict, then we evict
+ * those as well to make room for our guard pages.
+ */
+ if (i915_vm_has_cache_coloring(vm)) {
+ if (node->start + node->size == target->start) {
+ if (node->color == target->color)
+ continue;
+ }
+ if (node->start == target->start + target->size) {
+ if (node->color == target->color)
+ continue;
+ }
+ }
+
+ if (i915_vma_is_pinned(vma)) {
+ ret = -ENOSPC;
+ break;
+ }
+
+ if (flags & PIN_NONBLOCK && i915_vma_is_active(vma)) {
+ ret = -ENOSPC;
+ break;
+ }
+
+ if (!grab_vma(vma, ww)) {
+ ret = -ENOSPC;
+ break;
+ }
+
+ /*
+ * Never show fear in the face of dragons!
+ *
+ * We cannot directly remove this node from within this
+ * iterator and as with i915_gem_evict_something() we employ
+ * the vma pin_count in order to prevent the action of
+ * unbinding one vma from freeing (by dropping its active
+ * reference) another in our eviction list.
+ */
+ __i915_vma_pin(vma);
+ list_add(&vma->evict_link, &eviction_list);
+ }
+
+ list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
+ __i915_vma_unpin(vma);
+ if (ret == 0)
+ ret = __i915_vma_unbind(vma);
+
+ ungrab_vma(vma);
+ }
+
+ return ret;
+}
+
+/**
+ * i915_gem_evict_vm - Evict all idle vmas from a vm
+ * @vm: Address space to cleanse
+ * @ww: An optional struct i915_gem_ww_ctx. If not NULL, i915_gem_evict_vm
+ * will be able to evict vma's locked by the ww as well.
+ * @busy_bo: Optional pointer to struct drm_i915_gem_object. If not NULL, then
+ * in the event i915_gem_evict_vm() is unable to trylock an object for eviction,
+ * then @busy_bo will point to it. -EBUSY is also returned. The caller must drop
+ * the vm->mutex, before trying again to acquire the contended lock. The caller
+ * also owns a reference to the object.
+ *
+ * This function evicts all vmas from a vm.
+ *
+ * This is used by the execbuf code as a last-ditch effort to defragment the
+ * address space.
+ *
+ * To clarify: This is for freeing up virtual address space, not for freeing
+ * memory in e.g. the shrinker.
+ */
+int i915_gem_evict_vm(struct i915_address_space *vm, struct i915_gem_ww_ctx *ww,
+ struct drm_i915_gem_object **busy_bo)
+{
+ int ret = 0;
+
+ lockdep_assert_held(&vm->mutex);
+ trace_i915_gem_evict_vm(vm);
+
+ /* Switch back to the default context in order to unpin
+ * the existing context objects. However, such objects only
+ * pin themselves inside the global GTT and performing the
+ * switch otherwise is ineffective.
+ */
+ if (i915_is_ggtt(vm)) {
+ ret = ggtt_flush(vm->gt);
+ if (ret)
+ return ret;
+ }
+
+ do {
+ struct i915_vma *vma, *vn;
+ LIST_HEAD(eviction_list);
+ LIST_HEAD(locked_eviction_list);
+
+ list_for_each_entry(vma, &vm->bound_list, vm_link) {
+ if (i915_vma_is_pinned(vma))
+ continue;
+
+ /*
+ * If we already own the lock, trylock fails. In case
+ * the resv is shared among multiple objects, we still
+ * need the object ref.
+ */
+ if (!i915_gem_object_get_rcu(vma->obj) ||
+ (ww && (dma_resv_locking_ctx(vma->obj->base.resv) == &ww->ctx))) {
+ __i915_vma_pin(vma);
+ list_add(&vma->evict_link, &locked_eviction_list);
+ continue;
+ }
+
+ if (!i915_gem_object_trylock(vma->obj, ww)) {
+ if (busy_bo) {
+ *busy_bo = vma->obj; /* holds ref */
+ ret = -EBUSY;
+ break;
+ }
+ i915_gem_object_put(vma->obj);
+ continue;
+ }
+
+ __i915_vma_pin(vma);
+ list_add(&vma->evict_link, &eviction_list);
+ }
+ if (list_empty(&eviction_list) && list_empty(&locked_eviction_list))
+ break;
+
+ /* Unbind locked objects first, before unlocking the eviction_list */
+ list_for_each_entry_safe(vma, vn, &locked_eviction_list, evict_link) {
+ __i915_vma_unpin(vma);
+
+ if (ret == 0) {
+ ret = __i915_vma_unbind(vma);
+ if (ret != -EINTR) /* "Get me out of here!" */
+ ret = 0;
+ }
+ if (!dying_vma(vma))
+ i915_gem_object_put(vma->obj);
+ }
+
+ list_for_each_entry_safe(vma, vn, &eviction_list, evict_link) {
+ __i915_vma_unpin(vma);
+ if (ret == 0) {
+ ret = __i915_vma_unbind(vma);
+ if (ret != -EINTR) /* "Get me out of here!" */
+ ret = 0;
+ }
+
+ i915_gem_object_unlock(vma->obj);
+ i915_gem_object_put(vma->obj);
+ }
+ } while (ret == 0);
+
+ return ret;
+}
+
+#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
+#include "selftests/i915_gem_evict.c"
+#endif