From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- drivers/gpu/drm/drm_modeset_lock.c | 481 +++++++++++++++++++++++++++++++++++++ 1 file changed, 481 insertions(+) create mode 100644 drivers/gpu/drm/drm_modeset_lock.c (limited to 'drivers/gpu/drm/drm_modeset_lock.c') diff --git a/drivers/gpu/drm/drm_modeset_lock.c b/drivers/gpu/drm/drm_modeset_lock.c new file mode 100644 index 000000000..918065982 --- /dev/null +++ b/drivers/gpu/drm/drm_modeset_lock.c @@ -0,0 +1,481 @@ +/* + * Copyright (C) 2014 Red Hat + * Author: Rob Clark + * + * 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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. + */ + +#include +#include +#include +#include +#include + +/** + * DOC: kms locking + * + * As KMS moves toward more fine grained locking, and atomic ioctl where + * userspace can indirectly control locking order, it becomes necessary + * to use &ww_mutex and acquire-contexts to avoid deadlocks. But because + * the locking is more distributed around the driver code, we want a bit + * of extra utility/tracking out of our acquire-ctx. This is provided + * by &struct drm_modeset_lock and &struct drm_modeset_acquire_ctx. + * + * For basic principles of &ww_mutex, see: Documentation/locking/ww-mutex-design.rst + * + * The basic usage pattern is to:: + * + * drm_modeset_acquire_init(ctx, DRM_MODESET_ACQUIRE_INTERRUPTIBLE) + * retry: + * foreach (lock in random_ordered_set_of_locks) { + * ret = drm_modeset_lock(lock, ctx) + * if (ret == -EDEADLK) { + * ret = drm_modeset_backoff(ctx); + * if (!ret) + * goto retry; + * } + * if (ret) + * goto out; + * } + * ... do stuff ... + * out: + * drm_modeset_drop_locks(ctx); + * drm_modeset_acquire_fini(ctx); + * + * For convenience this control flow is implemented in + * DRM_MODESET_LOCK_ALL_BEGIN() and DRM_MODESET_LOCK_ALL_END() for the case + * where all modeset locks need to be taken through drm_modeset_lock_all_ctx(). + * + * If all that is needed is a single modeset lock, then the &struct + * drm_modeset_acquire_ctx is not needed and the locking can be simplified + * by passing a NULL instead of ctx in the drm_modeset_lock() call or + * calling drm_modeset_lock_single_interruptible(). To unlock afterwards + * call drm_modeset_unlock(). + * + * On top of these per-object locks using &ww_mutex there's also an overall + * &drm_mode_config.mutex, for protecting everything else. Mostly this means + * probe state of connectors, and preventing hotplug add/removal of connectors. + * + * Finally there's a bunch of dedicated locks to protect drm core internal + * lists and lookup data structures. + */ + +static DEFINE_WW_CLASS(crtc_ww_class); + +#if IS_ENABLED(CONFIG_DRM_DEBUG_MODESET_LOCK) +static noinline depot_stack_handle_t __drm_stack_depot_save(void) +{ + unsigned long entries[8]; + unsigned int n; + + n = stack_trace_save(entries, ARRAY_SIZE(entries), 1); + + return stack_depot_save(entries, n, GFP_NOWAIT | __GFP_NOWARN); +} + +static void __drm_stack_depot_print(depot_stack_handle_t stack_depot) +{ + struct drm_printer p = drm_debug_printer("drm_modeset_lock"); + unsigned long *entries; + unsigned int nr_entries; + char *buf; + + buf = kmalloc(PAGE_SIZE, GFP_NOWAIT | __GFP_NOWARN); + if (!buf) + return; + + nr_entries = stack_depot_fetch(stack_depot, &entries); + stack_trace_snprint(buf, PAGE_SIZE, entries, nr_entries, 2); + + drm_printf(&p, "attempting to lock a contended lock without backoff:\n%s", buf); + + kfree(buf); +} + +static void __drm_stack_depot_init(void) +{ + stack_depot_init(); +} +#else /* CONFIG_DRM_DEBUG_MODESET_LOCK */ +static depot_stack_handle_t __drm_stack_depot_save(void) +{ + return 0; +} +static void __drm_stack_depot_print(depot_stack_handle_t stack_depot) +{ +} +static void __drm_stack_depot_init(void) +{ +} +#endif /* CONFIG_DRM_DEBUG_MODESET_LOCK */ + +/** + * drm_modeset_lock_all - take all modeset locks + * @dev: DRM device + * + * This function takes all modeset locks, suitable where a more fine-grained + * scheme isn't (yet) implemented. Locks must be dropped by calling the + * drm_modeset_unlock_all() function. + * + * This function is deprecated. It allocates a lock acquisition context and + * stores it in &drm_device.mode_config. This facilitate conversion of + * existing code because it removes the need to manually deal with the + * acquisition context, but it is also brittle because the context is global + * and care must be taken not to nest calls. New code should use the + * drm_modeset_lock_all_ctx() function and pass in the context explicitly. + */ +void drm_modeset_lock_all(struct drm_device *dev) +{ + struct drm_mode_config *config = &dev->mode_config; + struct drm_modeset_acquire_ctx *ctx; + int ret; + + ctx = kzalloc(sizeof(*ctx), GFP_KERNEL | __GFP_NOFAIL); + if (WARN_ON(!ctx)) + return; + + mutex_lock(&config->mutex); + + drm_modeset_acquire_init(ctx, 0); + +retry: + ret = drm_modeset_lock_all_ctx(dev, ctx); + if (ret < 0) { + if (ret == -EDEADLK) { + drm_modeset_backoff(ctx); + goto retry; + } + + drm_modeset_acquire_fini(ctx); + kfree(ctx); + return; + } + ww_acquire_done(&ctx->ww_ctx); + + WARN_ON(config->acquire_ctx); + + /* + * We hold the locks now, so it is safe to stash the acquisition + * context for drm_modeset_unlock_all(). + */ + config->acquire_ctx = ctx; + + drm_warn_on_modeset_not_all_locked(dev); +} +EXPORT_SYMBOL(drm_modeset_lock_all); + +/** + * drm_modeset_unlock_all - drop all modeset locks + * @dev: DRM device + * + * This function drops all modeset locks taken by a previous call to the + * drm_modeset_lock_all() function. + * + * This function is deprecated. It uses the lock acquisition context stored + * in &drm_device.mode_config. This facilitates conversion of existing + * code because it removes the need to manually deal with the acquisition + * context, but it is also brittle because the context is global and care must + * be taken not to nest calls. New code should pass the acquisition context + * directly to the drm_modeset_drop_locks() function. + */ +void drm_modeset_unlock_all(struct drm_device *dev) +{ + struct drm_mode_config *config = &dev->mode_config; + struct drm_modeset_acquire_ctx *ctx = config->acquire_ctx; + + if (WARN_ON(!ctx)) + return; + + config->acquire_ctx = NULL; + drm_modeset_drop_locks(ctx); + drm_modeset_acquire_fini(ctx); + + kfree(ctx); + + mutex_unlock(&dev->mode_config.mutex); +} +EXPORT_SYMBOL(drm_modeset_unlock_all); + +/** + * drm_warn_on_modeset_not_all_locked - check that all modeset locks are locked + * @dev: device + * + * Useful as a debug assert. + */ +void drm_warn_on_modeset_not_all_locked(struct drm_device *dev) +{ + struct drm_crtc *crtc; + + /* Locking is currently fubar in the panic handler. */ + if (oops_in_progress) + return; + + drm_for_each_crtc(crtc, dev) + WARN_ON(!drm_modeset_is_locked(&crtc->mutex)); + + WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex)); + WARN_ON(!mutex_is_locked(&dev->mode_config.mutex)); +} +EXPORT_SYMBOL(drm_warn_on_modeset_not_all_locked); + +/** + * drm_modeset_acquire_init - initialize acquire context + * @ctx: the acquire context + * @flags: 0 or %DRM_MODESET_ACQUIRE_INTERRUPTIBLE + * + * When passing %DRM_MODESET_ACQUIRE_INTERRUPTIBLE to @flags, + * all calls to drm_modeset_lock() will perform an interruptible + * wait. + */ +void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx, + uint32_t flags) +{ + memset(ctx, 0, sizeof(*ctx)); + ww_acquire_init(&ctx->ww_ctx, &crtc_ww_class); + INIT_LIST_HEAD(&ctx->locked); + + if (flags & DRM_MODESET_ACQUIRE_INTERRUPTIBLE) + ctx->interruptible = true; +} +EXPORT_SYMBOL(drm_modeset_acquire_init); + +/** + * drm_modeset_acquire_fini - cleanup acquire context + * @ctx: the acquire context + */ +void drm_modeset_acquire_fini(struct drm_modeset_acquire_ctx *ctx) +{ + ww_acquire_fini(&ctx->ww_ctx); +} +EXPORT_SYMBOL(drm_modeset_acquire_fini); + +/** + * drm_modeset_drop_locks - drop all locks + * @ctx: the acquire context + * + * Drop all locks currently held against this acquire context. + */ +void drm_modeset_drop_locks(struct drm_modeset_acquire_ctx *ctx) +{ + if (WARN_ON(ctx->contended)) + __drm_stack_depot_print(ctx->stack_depot); + + while (!list_empty(&ctx->locked)) { + struct drm_modeset_lock *lock; + + lock = list_first_entry(&ctx->locked, + struct drm_modeset_lock, head); + + drm_modeset_unlock(lock); + } +} +EXPORT_SYMBOL(drm_modeset_drop_locks); + +static inline int modeset_lock(struct drm_modeset_lock *lock, + struct drm_modeset_acquire_ctx *ctx, + bool interruptible, bool slow) +{ + int ret; + + if (WARN_ON(ctx->contended)) + __drm_stack_depot_print(ctx->stack_depot); + + if (ctx->trylock_only) { + lockdep_assert_held(&ctx->ww_ctx); + + if (!ww_mutex_trylock(&lock->mutex, NULL)) + return -EBUSY; + else + return 0; + } else if (interruptible && slow) { + ret = ww_mutex_lock_slow_interruptible(&lock->mutex, &ctx->ww_ctx); + } else if (interruptible) { + ret = ww_mutex_lock_interruptible(&lock->mutex, &ctx->ww_ctx); + } else if (slow) { + ww_mutex_lock_slow(&lock->mutex, &ctx->ww_ctx); + ret = 0; + } else { + ret = ww_mutex_lock(&lock->mutex, &ctx->ww_ctx); + } + if (!ret) { + WARN_ON(!list_empty(&lock->head)); + list_add(&lock->head, &ctx->locked); + } else if (ret == -EALREADY) { + /* we already hold the lock.. this is fine. For atomic + * we will need to be able to drm_modeset_lock() things + * without having to keep track of what is already locked + * or not. + */ + ret = 0; + } else if (ret == -EDEADLK) { + ctx->contended = lock; + ctx->stack_depot = __drm_stack_depot_save(); + } + + return ret; +} + +/** + * drm_modeset_backoff - deadlock avoidance backoff + * @ctx: the acquire context + * + * If deadlock is detected (ie. drm_modeset_lock() returns -EDEADLK), + * you must call this function to drop all currently held locks and + * block until the contended lock becomes available. + * + * This function returns 0 on success, or -ERESTARTSYS if this context + * is initialized with %DRM_MODESET_ACQUIRE_INTERRUPTIBLE and the + * wait has been interrupted. + */ +int drm_modeset_backoff(struct drm_modeset_acquire_ctx *ctx) +{ + struct drm_modeset_lock *contended = ctx->contended; + + ctx->contended = NULL; + ctx->stack_depot = 0; + + if (WARN_ON(!contended)) + return 0; + + drm_modeset_drop_locks(ctx); + + return modeset_lock(contended, ctx, ctx->interruptible, true); +} +EXPORT_SYMBOL(drm_modeset_backoff); + +/** + * drm_modeset_lock_init - initialize lock + * @lock: lock to init + */ +void drm_modeset_lock_init(struct drm_modeset_lock *lock) +{ + ww_mutex_init(&lock->mutex, &crtc_ww_class); + INIT_LIST_HEAD(&lock->head); + __drm_stack_depot_init(); +} +EXPORT_SYMBOL(drm_modeset_lock_init); + +/** + * drm_modeset_lock - take modeset lock + * @lock: lock to take + * @ctx: acquire ctx + * + * If @ctx is not NULL, then its ww acquire context is used and the + * lock will be tracked by the context and can be released by calling + * drm_modeset_drop_locks(). If -EDEADLK is returned, this means a + * deadlock scenario has been detected and it is an error to attempt + * to take any more locks without first calling drm_modeset_backoff(). + * + * If the @ctx is not NULL and initialized with + * %DRM_MODESET_ACQUIRE_INTERRUPTIBLE, this function will fail with + * -ERESTARTSYS when interrupted. + * + * If @ctx is NULL then the function call behaves like a normal, + * uninterruptible non-nesting mutex_lock() call. + */ +int drm_modeset_lock(struct drm_modeset_lock *lock, + struct drm_modeset_acquire_ctx *ctx) +{ + if (ctx) + return modeset_lock(lock, ctx, ctx->interruptible, false); + + ww_mutex_lock(&lock->mutex, NULL); + return 0; +} +EXPORT_SYMBOL(drm_modeset_lock); + +/** + * drm_modeset_lock_single_interruptible - take a single modeset lock + * @lock: lock to take + * + * This function behaves as drm_modeset_lock() with a NULL context, + * but performs interruptible waits. + * + * This function returns 0 on success, or -ERESTARTSYS when interrupted. + */ +int drm_modeset_lock_single_interruptible(struct drm_modeset_lock *lock) +{ + return ww_mutex_lock_interruptible(&lock->mutex, NULL); +} +EXPORT_SYMBOL(drm_modeset_lock_single_interruptible); + +/** + * drm_modeset_unlock - drop modeset lock + * @lock: lock to release + */ +void drm_modeset_unlock(struct drm_modeset_lock *lock) +{ + list_del_init(&lock->head); + ww_mutex_unlock(&lock->mutex); +} +EXPORT_SYMBOL(drm_modeset_unlock); + +/** + * drm_modeset_lock_all_ctx - take all modeset locks + * @dev: DRM device + * @ctx: lock acquisition context + * + * This function takes all modeset locks, suitable where a more fine-grained + * scheme isn't (yet) implemented. + * + * Unlike drm_modeset_lock_all(), it doesn't take the &drm_mode_config.mutex + * since that lock isn't required for modeset state changes. Callers which + * need to grab that lock too need to do so outside of the acquire context + * @ctx. + * + * Locks acquired with this function should be released by calling the + * drm_modeset_drop_locks() function on @ctx. + * + * See also: DRM_MODESET_LOCK_ALL_BEGIN() and DRM_MODESET_LOCK_ALL_END() + * + * Returns: 0 on success or a negative error-code on failure. + */ +int drm_modeset_lock_all_ctx(struct drm_device *dev, + struct drm_modeset_acquire_ctx *ctx) +{ + struct drm_private_obj *privobj; + struct drm_crtc *crtc; + struct drm_plane *plane; + int ret; + + ret = drm_modeset_lock(&dev->mode_config.connection_mutex, ctx); + if (ret) + return ret; + + drm_for_each_crtc(crtc, dev) { + ret = drm_modeset_lock(&crtc->mutex, ctx); + if (ret) + return ret; + } + + drm_for_each_plane(plane, dev) { + ret = drm_modeset_lock(&plane->mutex, ctx); + if (ret) + return ret; + } + + drm_for_each_privobj(privobj, dev) { + ret = drm_modeset_lock(&privobj->lock, ctx); + if (ret) + return ret; + } + + return 0; +} +EXPORT_SYMBOL(drm_modeset_lock_all_ctx); -- cgit v1.2.3