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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0 OR MIT
 /*
  * Copyright 2014-2022 Advanced Micro Devices, Inc.
  *
  * 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 <linux/mm_types.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 #include <linux/sched/signal.h>
 #include <linux/sched/mm.h>
 #include <linux/uaccess.h>
 #include <linux/mman.h>
 #include <linux/memory.h>
 #include "kfd_priv.h"
 #include "kfd_events.h"
 #include "kfd_iommu.h"
 #include <linux/device.h>
 
 /*
  * Wrapper around wait_queue_entry_t
  */
 struct kfd_event_waiter {
     wait_queue_entry_t wait;
     struct kfd_event *event; /* Event to wait for */
     bool activated;      /* Becomes true when event is signaled */
 };
 
 /*
  * Each signal event needs a 64-bit signal slot where the signaler will write
  * a 1 before sending an interrupt. (This is needed because some interrupts
  * do not contain enough spare data bits to identify an event.)
  * We get whole pages and map them to the process VA.
  * Individual signal events use their event_id as slot index.
  */
 struct kfd_signal_page {
     uint64_t *kernel_address;
     uint64_t __user *user_address;
     bool need_to_free_pages;
 };
 
 static uint64_t *page_slots(struct kfd_signal_page *page)
 {
     return page->kernel_address;
 }
 
 static struct kfd_signal_page *allocate_signal_page(struct kfd_process *p)
 {
     void *backing_store;
     struct kfd_signal_page *page;
 
     page = kzalloc(sizeof(*page), GFP_KERNEL);
     if (!page)
         return NULL;
 
     backing_store = (void *) __get_free_pages(GFP_KERNEL,
                     get_order(KFD_SIGNAL_EVENT_LIMIT * 8));
     if (!backing_store)
         goto fail_alloc_signal_store;
 
     /* Initialize all events to unsignaled */
     memset(backing_store, (uint8_t) UNSIGNALED_EVENT_SLOT,
            KFD_SIGNAL_EVENT_LIMIT * 8);
 
     page->kernel_address = backing_store;
     page->need_to_free_pages = true;
     pr_debug("Allocated new event signal page at %p, for process %p\n",
             page, p);
 
     return page;
 
 fail_alloc_signal_store:
     kfree(page);
     return NULL;
 }
 
 static int allocate_event_notification_slot(struct kfd_process *p,
                         struct kfd_event *ev,
                         const int *restore_id)
 {
     int id;
 
     if (!p->signal_page) {
         p->signal_page = allocate_signal_page(p);
         if (!p->signal_page)
             return -ENOMEM;
         /* Oldest user mode expects 256 event slots */
         p->signal_mapped_size = 256*8;
     }
 
     if (restore_id) {
         id = idr_alloc(&p->event_idr, ev, *restore_id, *restore_id + 1,
                 GFP_KERNEL);
     } else {
         /*
          * Compatibility with old user mode: Only use signal slots
          * user mode has mapped, may be less than
          * KFD_SIGNAL_EVENT_LIMIT. This also allows future increase
          * of the event limit without breaking user mode.
          */
         id = idr_alloc(&p->event_idr, ev, 0, p->signal_mapped_size / 8,
                 GFP_KERNEL);
     }
     if (id < 0)
         return id;
 
     ev->event_id = id;
     page_slots(p->signal_page)[id] = UNSIGNALED_EVENT_SLOT;
 
     return 0;
 }
 
 /*
  * Assumes that p->event_mutex or rcu_readlock is held and of course that p is
  * not going away.
  */
 static struct kfd_event *lookup_event_by_id(struct kfd_process *p, uint32_t id)
 {
     return idr_find(&p->event_idr, id);
 }
 
 /**
  * lookup_signaled_event_by_partial_id - Lookup signaled event from partial ID
  * @p:     Pointer to struct kfd_process
  * @id:    ID to look up
  * @bits:  Number of valid bits in @id
  *
  * Finds the first signaled event with a matching partial ID. If no
  * matching signaled event is found, returns NULL. In that case the
  * caller should assume that the partial ID is invalid and do an
  * exhaustive search of all siglaned events.
  *
  * If multiple events with the same partial ID signal at the same
  * time, they will be found one interrupt at a time, not necessarily
  * in the same order the interrupts occurred. As long as the number of
  * interrupts is correct, all signaled events will be seen by the
  * driver.
  */
 static struct kfd_event *lookup_signaled_event_by_partial_id(
     struct kfd_process *p, uint32_t id, uint32_t bits)
 {
     struct kfd_event *ev;
 
     if (!p->signal_page || id >= KFD_SIGNAL_EVENT_LIMIT)
         return NULL;
 
     /* Fast path for the common case that @id is not a partial ID
      * and we only need a single lookup.
      */
     if (bits > 31 || (1U << bits) >= KFD_SIGNAL_EVENT_LIMIT) {
         if (page_slots(p->signal_page)[id] == UNSIGNALED_EVENT_SLOT)
             return NULL;
 
         return idr_find(&p->event_idr, id);
     }
 
     /* General case for partial IDs: Iterate over all matching IDs
      * and find the first one that has signaled.
      */
     for (ev = NULL; id < KFD_SIGNAL_EVENT_LIMIT && !ev; id += 1U << bits) {
         if (page_slots(p->signal_page)[id] == UNSIGNALED_EVENT_SLOT)
             continue;
 
         ev = idr_find(&p->event_idr, id);
     }
 
     return ev;
 }
 
 static int create_signal_event(struct file *devkfd, struct kfd_process *p,
                 struct kfd_event *ev, const int *restore_id)
 {
     int ret;
 
     if (p->signal_mapped_size &&
         p->signal_event_count == p->signal_mapped_size / 8) {
         if (!p->signal_event_limit_reached) {
             pr_debug("Signal event wasn't created because limit was reached\n");
             p->signal_event_limit_reached = true;
         }
         return -ENOSPC;
     }
 
     ret = allocate_event_notification_slot(p, ev, restore_id);
     if (ret) {
         pr_warn("Signal event wasn't created because out of kernel memory\n");
         return ret;
     }
 
     p->signal_event_count++;
 
     ev->user_signal_address = &p->signal_page->user_address[ev->event_id];
     pr_debug("Signal event number %zu created with id %d, address %p\n",
             p->signal_event_count, ev->event_id,
             ev->user_signal_address);
 
     return 0;
 }
 
 static int create_other_event(struct kfd_process *p, struct kfd_event *ev, const int *restore_id)
 {
     int id;
 
     if (restore_id)
         id = idr_alloc(&p->event_idr, ev, *restore_id, *restore_id + 1,
             GFP_KERNEL);
     else
         /* Cast KFD_LAST_NONSIGNAL_EVENT to uint32_t. This allows an
          * intentional integer overflow to -1 without a compiler
          * warning. idr_alloc treats a negative value as "maximum
          * signed integer".
          */
         id = idr_alloc(&p->event_idr, ev, KFD_FIRST_NONSIGNAL_EVENT_ID,
                 (uint32_t)KFD_LAST_NONSIGNAL_EVENT_ID + 1,
                 GFP_KERNEL);
 
     if (id < 0)
         return id;
     ev->event_id = id;
 
     return 0;
 }
 
 int kfd_event_init_process(struct kfd_process *p)
 {
     int id;
 
     mutex_init(&p->event_mutex);
     idr_init(&p->event_idr);
     p->signal_page = NULL;
     p->signal_event_count = 1;
     /* Allocate event ID 0. It is used for a fast path to ignore bogus events
      * that are sent by the CP without a context ID
      */
     id = idr_alloc(&p->event_idr, NULL, 0, 1, GFP_KERNEL);
     if (id < 0) {
         idr_destroy(&p->event_idr);
         mutex_destroy(&p->event_mutex);
         return id;
     }
     return 0;
 }
 
 static void destroy_event(struct kfd_process *p, struct kfd_event *ev)
 {
     struct kfd_event_waiter *waiter;
 
     /* Wake up pending waiters. They will return failure */
     spin_lock(&ev->lock);
     list_for_each_entry(waiter, &ev->wq.head, wait.entry)
         WRITE_ONCE(waiter->event, NULL);
     wake_up_all(&ev->wq);
     spin_unlock(&ev->lock);
 
     if (ev->type == KFD_EVENT_TYPE_SIGNAL ||
         ev->type == KFD_EVENT_TYPE_DEBUG)
         p->signal_event_count--;
 
     idr_remove(&p->event_idr, ev->event_id);
     kfree_rcu(ev, rcu);
 }
 
 static void destroy_events(struct kfd_process *p)
 {
     struct kfd_event *ev;
     uint32_t id;
 
     idr_for_each_entry(&p->event_idr, ev, id)
         if (ev)
             destroy_event(p, ev);
     idr_destroy(&p->event_idr);
     mutex_destroy(&p->event_mutex);
 }
 
 /*
  * We assume that the process is being destroyed and there is no need to
  * unmap the pages or keep bookkeeping data in order.
  */
 static void shutdown_signal_page(struct kfd_process *p)
 {
     struct kfd_signal_page *page = p->signal_page;
 
     if (page) {
         if (page->need_to_free_pages)
             free_pages((unsigned long)page->kernel_address,
                    get_order(KFD_SIGNAL_EVENT_LIMIT * 8));
         kfree(page);
     }
 }
 
 void kfd_event_free_process(struct kfd_process *p)
 {
     destroy_events(p);
     shutdown_signal_page(p);
 }
 
 static bool event_can_be_gpu_signaled(const struct kfd_event *ev)
 {
     return ev->type == KFD_EVENT_TYPE_SIGNAL ||
                     ev->type == KFD_EVENT_TYPE_DEBUG;
 }
 
 static bool event_can_be_cpu_signaled(const struct kfd_event *ev)
 {
     return ev->type == KFD_EVENT_TYPE_SIGNAL;
 }
 
 static int kfd_event_page_set(struct kfd_process *p, void *kernel_address,
                uint64_t size, uint64_t user_handle)
 {
     struct kfd_signal_page *page;
 
     if (p->signal_page)
         return -EBUSY;
 
     page = kzalloc(sizeof(*page), GFP_KERNEL);
     if (!page)
         return -ENOMEM;
 
     /* Initialize all events to unsignaled */
     memset(kernel_address, (uint8_t) UNSIGNALED_EVENT_SLOT,
            KFD_SIGNAL_EVENT_LIMIT * 8);
 
     page->kernel_address = kernel_address;
 
     p->signal_page = page;
     p->signal_mapped_size = size;
     p->signal_handle = user_handle;
     return 0;
 }
 
 int kfd_kmap_event_page(struct kfd_process *p, uint64_t event_page_offset)
 {
     struct kfd_dev *kfd;
     struct kfd_process_device *pdd;
     void *mem, *kern_addr;
     uint64_t size;
     int err = 0;
 
     if (p->signal_page) {
         pr_err("Event page is already set\n");
         return -EINVAL;
     }
 
     pdd = kfd_process_device_data_by_id(p, GET_GPU_ID(event_page_offset));
     if (!pdd) {
         pr_err("Getting device by id failed in %s\n", __func__);
         return -EINVAL;
     }
     kfd = pdd->dev;
 
     pdd = kfd_bind_process_to_device(kfd, p);
     if (IS_ERR(pdd))
         return PTR_ERR(pdd);
 
     mem = kfd_process_device_translate_handle(pdd,
             GET_IDR_HANDLE(event_page_offset));
     if (!mem) {
         pr_err("Can't find BO, offset is 0x%llx\n", event_page_offset);
         return -EINVAL;
     }
 
     err = amdgpu_amdkfd_gpuvm_map_gtt_bo_to_kernel(mem, &kern_addr, &size);
     if (err) {
         pr_err("Failed to map event page to kernel\n");
         return err;
     }
 
     err = kfd_event_page_set(p, kern_addr, size, event_page_offset);
     if (err) {
         pr_err("Failed to set event page\n");
         amdgpu_amdkfd_gpuvm_unmap_gtt_bo_from_kernel(mem);
         return err;
     }
     return err;
 }
 
 int kfd_event_create(struct file *devkfd, struct kfd_process *p,
              uint32_t event_type, bool auto_reset, uint32_t node_id,
              uint32_t *event_id, uint32_t *event_trigger_data,
              uint64_t *event_page_offset, uint32_t *event_slot_index)
 {
     int ret = 0;
     struct kfd_event *ev = kzalloc(sizeof(*ev), GFP_KERNEL);
 
     if (!ev)
         return -ENOMEM;
 
     ev->type = event_type;
     ev->auto_reset = auto_reset;
     ev->signaled = false;
 
     spin_lock_init(&ev->lock);
     init_waitqueue_head(&ev->wq);
 
     *event_page_offset = 0;
 
     mutex_lock(&p->event_mutex);
 
     switch (event_type) {
     case KFD_EVENT_TYPE_SIGNAL:
     case KFD_EVENT_TYPE_DEBUG:
         ret = create_signal_event(devkfd, p, ev, NULL);
         if (!ret) {
             *event_page_offset = KFD_MMAP_TYPE_EVENTS;
             *event_slot_index = ev->event_id;
         }
         break;
     default:
         ret = create_other_event(p, ev, NULL);
         break;
     }
 
     if (!ret) {
         *event_id = ev->event_id;
         *event_trigger_data = ev->event_id;
     } else {
         kfree(ev);
     }
 
     mutex_unlock(&p->event_mutex);
 
     return ret;
 }
 
 int kfd_criu_restore_event(struct file *devkfd,
                struct kfd_process *p,
                uint8_t __user *user_priv_ptr,
                uint64_t *priv_data_offset,
                uint64_t max_priv_data_size)
 {
     struct kfd_criu_event_priv_data *ev_priv;
     struct kfd_event *ev = NULL;
     int ret = 0;
 
     ev_priv = kmalloc(sizeof(*ev_priv), GFP_KERNEL);
     if (!ev_priv)
         return -ENOMEM;
 
     ev = kzalloc(sizeof(*ev), GFP_KERNEL);
     if (!ev) {
         ret = -ENOMEM;
         goto exit;
     }
 
     if (*priv_data_offset + sizeof(*ev_priv) > max_priv_data_size) {
         ret = -EINVAL;
         goto exit;
     }
 
     ret = copy_from_user(ev_priv, user_priv_ptr + *priv_data_offset, sizeof(*ev_priv));
     if (ret) {
         ret = -EFAULT;
         goto exit;
     }
     *priv_data_offset += sizeof(*ev_priv);
 
     if (ev_priv->user_handle) {
         ret = kfd_kmap_event_page(p, ev_priv->user_handle);
         if (ret)
             goto exit;
     }
 
     ev->type = ev_priv->type;
     ev->auto_reset = ev_priv->auto_reset;
     ev->signaled = ev_priv->signaled;
 
     spin_lock_init(&ev->lock);
     init_waitqueue_head(&ev->wq);
 
     mutex_lock(&p->event_mutex);
     switch (ev->type) {
     case KFD_EVENT_TYPE_SIGNAL:
     case KFD_EVENT_TYPE_DEBUG:
         ret = create_signal_event(devkfd, p, ev, &ev_priv->event_id);
         break;
     case KFD_EVENT_TYPE_MEMORY:
         memcpy(&ev->memory_exception_data,
             &ev_priv->memory_exception_data,
             sizeof(struct kfd_hsa_memory_exception_data));
 
         ret = create_other_event(p, ev, &ev_priv->event_id);
         break;
     case KFD_EVENT_TYPE_HW_EXCEPTION:
         memcpy(&ev->hw_exception_data,
             &ev_priv->hw_exception_data,
             sizeof(struct kfd_hsa_hw_exception_data));
 
         ret = create_other_event(p, ev, &ev_priv->event_id);
         break;
     }
 
 exit:
     if (ret)
         kfree(ev);
 
     kfree(ev_priv);
 
     mutex_unlock(&p->event_mutex);
 
     return ret;
 }
 
 int kfd_criu_checkpoint_events(struct kfd_process *p,
              uint8_t __user *user_priv_data,
              uint64_t *priv_data_offset)
 {
     struct kfd_criu_event_priv_data *ev_privs;
     int i = 0;
     int ret =  0;
     struct kfd_event *ev;
     uint32_t ev_id;
 
     uint32_t num_events = kfd_get_num_events(p);
 
     if (!num_events)
         return 0;
 
     ev_privs = kvzalloc(num_events * sizeof(*ev_privs), GFP_KERNEL);
     if (!ev_privs)
         return -ENOMEM;
 
 
     idr_for_each_entry(&p->event_idr, ev, ev_id) {
         struct kfd_criu_event_priv_data *ev_priv;
 
         /*
          * Currently, all events have same size of private_data, but the current ioctl's
          * and CRIU plugin supports private_data of variable sizes
          */
         ev_priv = &ev_privs[i];
 
         ev_priv->object_type = KFD_CRIU_OBJECT_TYPE_EVENT;
 
         /* We store the user_handle with the first event */
         if (i == 0 && p->signal_page)
             ev_priv->user_handle = p->signal_handle;
 
         ev_priv->event_id = ev->event_id;
         ev_priv->auto_reset = ev->auto_reset;
         ev_priv->type = ev->type;
         ev_priv->signaled = ev->signaled;
 
         if (ev_priv->type == KFD_EVENT_TYPE_MEMORY)
             memcpy(&ev_priv->memory_exception_data,
                 &ev->memory_exception_data,
                 sizeof(struct kfd_hsa_memory_exception_data));
         else if (ev_priv->type == KFD_EVENT_TYPE_HW_EXCEPTION)
             memcpy(&ev_priv->hw_exception_data,
                 &ev->hw_exception_data,
                 sizeof(struct kfd_hsa_hw_exception_data));
 
         pr_debug("Checkpointed event[%d] id = 0x%08x auto_reset = %x type = %x signaled = %x\n",
               i,
               ev_priv->event_id,
               ev_priv->auto_reset,
               ev_priv->type,
               ev_priv->signaled);
         i++;
     }
 
     ret = copy_to_user(user_priv_data + *priv_data_offset,
                ev_privs, num_events * sizeof(*ev_privs));
     if (ret) {
         pr_err("Failed to copy events priv to user\n");
         ret = -EFAULT;
     }
 
     *priv_data_offset += num_events * sizeof(*ev_privs);
 
     kvfree(ev_privs);
     return ret;
 }
 
 int kfd_get_num_events(struct kfd_process *p)
 {
     struct kfd_event *ev;
     uint32_t id;
     u32 num_events = 0;
 
     idr_for_each_entry(&p->event_idr, ev, id)
         num_events++;
 
     return num_events;
 }
 
 /* Assumes that p is current. */
 int kfd_event_destroy(struct kfd_process *p, uint32_t event_id)
 {
     struct kfd_event *ev;
     int ret = 0;
 
     mutex_lock(&p->event_mutex);
 
     ev = lookup_event_by_id(p, event_id);
 
     if (ev)
         destroy_event(p, ev);
     else
         ret = -EINVAL;
 
     mutex_unlock(&p->event_mutex);
     return ret;
 }
 
 static void set_event(struct kfd_event *ev)
 {
     struct kfd_event_waiter *waiter;
 
     /* Auto reset if the list is non-empty and we're waking
      * someone. waitqueue_active is safe here because we're
      * protected by the ev->lock, which is also held when
      * updating the wait queues in kfd_wait_on_events.
      */
     ev->signaled = !ev->auto_reset || !waitqueue_active(&ev->wq);
 
     list_for_each_entry(waiter, &ev->wq.head, wait.entry)
         WRITE_ONCE(waiter->activated, true);
 
     wake_up_all(&ev->wq);
 }
 
 /* Assumes that p is current. */
 int kfd_set_event(struct kfd_process *p, uint32_t event_id)
 {
     int ret = 0;
     struct kfd_event *ev;
 
     rcu_read_lock();
 
     ev = lookup_event_by_id(p, event_id);
     if (!ev) {
         ret = -EINVAL;
         goto unlock_rcu;
     }
     spin_lock(&ev->lock);
 
     if (event_can_be_cpu_signaled(ev))
         set_event(ev);
     else
         ret = -EINVAL;
 
     spin_unlock(&ev->lock);
 unlock_rcu:
     rcu_read_unlock();
     return ret;
 }
 
 static void reset_event(struct kfd_event *ev)
 {
     ev->signaled = false;
 }
 
 /* Assumes that p is current. */
 int kfd_reset_event(struct kfd_process *p, uint32_t event_id)
 {
     int ret = 0;
     struct kfd_event *ev;
 
     rcu_read_lock();
 
     ev = lookup_event_by_id(p, event_id);
     if (!ev) {
         ret = -EINVAL;
         goto unlock_rcu;
     }
     spin_lock(&ev->lock);
 
     if (event_can_be_cpu_signaled(ev))
         reset_event(ev);
     else
         ret = -EINVAL;
 
     spin_unlock(&ev->lock);
 unlock_rcu:
     rcu_read_unlock();
     return ret;
 
 }
 
 static void acknowledge_signal(struct kfd_process *p, struct kfd_event *ev)
 {
     WRITE_ONCE(page_slots(p->signal_page)[ev->event_id], UNSIGNALED_EVENT_SLOT);
 }
 
 static void set_event_from_interrupt(struct kfd_process *p,
                     struct kfd_event *ev)
 {
     if (ev && event_can_be_gpu_signaled(ev)) {
         acknowledge_signal(p, ev);
         spin_lock(&ev->lock);
         set_event(ev);
         spin_unlock(&ev->lock);
     }
 }
 
 void kfd_signal_event_interrupt(u32 pasid, uint32_t partial_id,
                 uint32_t valid_id_bits)
 {
     struct kfd_event *ev = NULL;
 
     /*
      * Because we are called from arbitrary context (workqueue) as opposed
      * to process context, kfd_process could attempt to exit while we are
      * running so the lookup function increments the process ref count.
      */
     struct kfd_process *p = kfd_lookup_process_by_pasid(pasid);
 
     if (!p)
         return; /* Presumably process exited. */
 
     rcu_read_lock();
 
     if (valid_id_bits)
         ev = lookup_signaled_event_by_partial_id(p, partial_id,
                              valid_id_bits);
     if (ev) {
         set_event_from_interrupt(p, ev);
     } else if (p->signal_page) {
         /*
          * Partial ID lookup failed. Assume that the event ID
          * in the interrupt payload was invalid and do an
          * exhaustive search of signaled events.
          */
         uint64_t *slots = page_slots(p->signal_page);
         uint32_t id;
 
         if (valid_id_bits)
             pr_debug_ratelimited("Partial ID invalid: %u (%u valid bits)\n",
                          partial_id, valid_id_bits);
 
         if (p->signal_event_count < KFD_SIGNAL_EVENT_LIMIT / 64) {
             /* With relatively few events, it's faster to
              * iterate over the event IDR
              */
             idr_for_each_entry(&p->event_idr, ev, id) {
                 if (id >= KFD_SIGNAL_EVENT_LIMIT)
                     break;
 
                 if (READ_ONCE(slots[id]) != UNSIGNALED_EVENT_SLOT)
                     set_event_from_interrupt(p, ev);
             }
         } else {
             /* With relatively many events, it's faster to
              * iterate over the signal slots and lookup
              * only signaled events from the IDR.
              */
             for (id = 1; id < KFD_SIGNAL_EVENT_LIMIT; id++)
                 if (READ_ONCE(slots[id]) != UNSIGNALED_EVENT_SLOT) {
                     ev = lookup_event_by_id(p, id);
                     set_event_from_interrupt(p, ev);
                 }
         }
     }
 
     rcu_read_unlock();
     kfd_unref_process(p);
 }
 
 static struct kfd_event_waiter *alloc_event_waiters(uint32_t num_events)
 {
     struct kfd_event_waiter *event_waiters;
     uint32_t i;
 
     event_waiters = kmalloc_array(num_events,
                     sizeof(struct kfd_event_waiter),
                     GFP_KERNEL);
     if (!event_waiters)
         return NULL;
 
     for (i = 0; (event_waiters) && (i < num_events) ; i++) {
         init_wait(&event_waiters[i].wait);
         event_waiters[i].activated = false;
     }
 
     return event_waiters;
 }
 
 static int init_event_waiter(struct kfd_process *p,
         struct kfd_event_waiter *waiter,
         uint32_t event_id)
 {
     struct kfd_event *ev = lookup_event_by_id(p, event_id);
 
     if (!ev)
         return -EINVAL;
 
     spin_lock(&ev->lock);
     waiter->event = ev;
     waiter->activated = ev->signaled;
     ev->signaled = ev->signaled && !ev->auto_reset;
     if (!waiter->activated)
         add_wait_queue(&ev->wq, &waiter->wait);
     spin_unlock(&ev->lock);
 
     return 0;
 }
 
 /* test_event_condition - Test condition of events being waited for
  * @all:           Return completion only if all events have signaled
  * @num_events:    Number of events to wait for
  * @event_waiters: Array of event waiters, one per event
  *
  * Returns KFD_IOC_WAIT_RESULT_COMPLETE if all (or one) event(s) have
  * signaled. Returns KFD_IOC_WAIT_RESULT_TIMEOUT if no (or not all)
  * events have signaled. Returns KFD_IOC_WAIT_RESULT_FAIL if any of
  * the events have been destroyed.
  */
 static uint32_t test_event_condition(bool all, uint32_t num_events,
                 struct kfd_event_waiter *event_waiters)
 {
     uint32_t i;
     uint32_t activated_count = 0;
 
     for (i = 0; i < num_events; i++) {
         if (!READ_ONCE(event_waiters[i].event))
             return KFD_IOC_WAIT_RESULT_FAIL;
 
         if (READ_ONCE(event_waiters[i].activated)) {
             if (!all)
                 return KFD_IOC_WAIT_RESULT_COMPLETE;
 
             activated_count++;
         }
     }
 
     return activated_count == num_events ?
         KFD_IOC_WAIT_RESULT_COMPLETE : KFD_IOC_WAIT_RESULT_TIMEOUT;
 }
 
 /*
  * Copy event specific data, if defined.
  * Currently only memory exception events have additional data to copy to user
  */
 static int copy_signaled_event_data(uint32_t num_events,
         struct kfd_event_waiter *event_waiters,
         struct kfd_event_data __user *data)
 {
     struct kfd_hsa_memory_exception_data *src;
     struct kfd_hsa_memory_exception_data __user *dst;
     struct kfd_event_waiter *waiter;
     struct kfd_event *event;
     uint32_t i;
 
     for (i = 0; i < num_events; i++) {
         waiter = &event_waiters[i];
         event = waiter->event;
         if (!event)
             return -EINVAL; /* event was destroyed */
         if (waiter->activated && event->type == KFD_EVENT_TYPE_MEMORY) {
             dst = &data[i].memory_exception_data;
             src = &event->memory_exception_data;
             if (copy_to_user(dst, src,
                 sizeof(struct kfd_hsa_memory_exception_data)))
                 return -EFAULT;
         }
     }
 
     return 0;
 }
 
 static long user_timeout_to_jiffies(uint32_t user_timeout_ms)
 {
     if (user_timeout_ms == KFD_EVENT_TIMEOUT_IMMEDIATE)
         return 0;
 
     if (user_timeout_ms == KFD_EVENT_TIMEOUT_INFINITE)
         return MAX_SCHEDULE_TIMEOUT;
 
     /*
      * msecs_to_jiffies interprets all values above 2^31-1 as infinite,
      * but we consider them finite.
      * This hack is wrong, but nobody is likely to notice.
      */
     user_timeout_ms = min_t(uint32_t, user_timeout_ms, 0x7FFFFFFF);
 
     return msecs_to_jiffies(user_timeout_ms) + 1;
 }
 
 static void free_waiters(uint32_t num_events, struct kfd_event_waiter *waiters,
              bool undo_auto_reset)
 {
     uint32_t i;
 
     for (i = 0; i < num_events; i++)
         if (waiters[i].event) {
             spin_lock(&waiters[i].event->lock);
             remove_wait_queue(&waiters[i].event->wq,
                       &waiters[i].wait);
             if (undo_auto_reset && waiters[i].activated &&
                 waiters[i].event && waiters[i].event->auto_reset)
                 set_event(waiters[i].event);
             spin_unlock(&waiters[i].event->lock);
         }
 
     kfree(waiters);
 }
 
 int kfd_wait_on_events(struct kfd_process *p,
                uint32_t num_events, void __user *data,
                bool all, uint32_t *user_timeout_ms,
                uint32_t *wait_result)
 {
     struct kfd_event_data __user *events =
             (struct kfd_event_data __user *) data;
     uint32_t i;
     int ret = 0;
 
     struct kfd_event_waiter *event_waiters = NULL;
     long timeout = user_timeout_to_jiffies(*user_timeout_ms);
 
     event_waiters = alloc_event_waiters(num_events);
     if (!event_waiters) {
         ret = -ENOMEM;
         goto out;
     }
 
     /* Use p->event_mutex here to protect against concurrent creation and
      * destruction of events while we initialize event_waiters.
      */
     mutex_lock(&p->event_mutex);
 
     for (i = 0; i < num_events; i++) {
         struct kfd_event_data event_data;
 
         if (copy_from_user(&event_data, &events[i],
                 sizeof(struct kfd_event_data))) {
             ret = -EFAULT;
             goto out_unlock;
         }
 
         ret = init_event_waiter(p, &event_waiters[i],
                     event_data.event_id);
         if (ret)
             goto out_unlock;
     }
 
     /* Check condition once. */
     *wait_result = test_event_condition(all, num_events, event_waiters);
     if (*wait_result == KFD_IOC_WAIT_RESULT_COMPLETE) {
         ret = copy_signaled_event_data(num_events,
                            event_waiters, events);
         goto out_unlock;
     } else if (WARN_ON(*wait_result == KFD_IOC_WAIT_RESULT_FAIL)) {
         /* This should not happen. Events shouldn't be
          * destroyed while we're holding the event_mutex
          */
         goto out_unlock;
     }
 
     mutex_unlock(&p->event_mutex);
 
     while (true) {
         if (fatal_signal_pending(current)) {
             ret = -EINTR;
             break;
         }
 
         if (signal_pending(current)) {
             ret = -ERESTARTSYS;
             if (*user_timeout_ms != KFD_EVENT_TIMEOUT_IMMEDIATE &&
                 *user_timeout_ms != KFD_EVENT_TIMEOUT_INFINITE)
                 *user_timeout_ms = jiffies_to_msecs(
                     max(0l, timeout-1));
             break;
         }
 
         /* Set task state to interruptible sleep before
          * checking wake-up conditions. A concurrent wake-up
          * will put the task back into runnable state. In that
          * case schedule_timeout will not put the task to
          * sleep and we'll get a chance to re-check the
          * updated conditions almost immediately. Otherwise,
          * this race condition would lead to a soft hang or a
          * very long sleep.
          */
         set_current_state(TASK_INTERRUPTIBLE);
 
         *wait_result = test_event_condition(all, num_events,
                             event_waiters);
         if (*wait_result != KFD_IOC_WAIT_RESULT_TIMEOUT)
             break;
 
         if (timeout <= 0)
             break;
 
         timeout = schedule_timeout(timeout);
     }
     __set_current_state(TASK_RUNNING);
 
     mutex_lock(&p->event_mutex);
     /* copy_signaled_event_data may sleep. So this has to happen
      * after the task state is set back to RUNNING.
      *
      * The event may also have been destroyed after signaling. So
      * copy_signaled_event_data also must confirm that the event
      * still exists. Therefore this must be under the p->event_mutex
      * which is also held when events are destroyed.
      */
     if (!ret && *wait_result == KFD_IOC_WAIT_RESULT_COMPLETE)
         ret = copy_signaled_event_data(num_events,
                            event_waiters, events);
 
 out_unlock:
     free_waiters(num_events, event_waiters, ret == -ERESTARTSYS);
     mutex_unlock(&p->event_mutex);
 out:
     if (ret)
         *wait_result = KFD_IOC_WAIT_RESULT_FAIL;
     else if (*wait_result == KFD_IOC_WAIT_RESULT_FAIL)
         ret = -EIO;
 
     return ret;
 }
 
 int kfd_event_mmap(struct kfd_process *p, struct vm_area_struct *vma)
 {
     unsigned long pfn;
     struct kfd_signal_page *page;
     int ret;
 
     /* check required size doesn't exceed the allocated size */
     if (get_order(KFD_SIGNAL_EVENT_LIMIT * 8) <
             get_order(vma->vm_end - vma->vm_start)) {
         pr_err("Event page mmap requested illegal size\n");
         return -EINVAL;
     }
 
     page = p->signal_page;
     if (!page) {
         /* Probably KFD bug, but mmap is user-accessible. */
         pr_debug("Signal page could not be found\n");
         return -EINVAL;
     }
 
     pfn = __pa(page->kernel_address);
     pfn >>= PAGE_SHIFT;
 
     vma->vm_flags |= VM_IO | VM_DONTCOPY | VM_DONTEXPAND | VM_NORESERVE
                | VM_DONTDUMP | VM_PFNMAP;
 
     pr_debug("Mapping signal page\n");
     pr_debug("     start user address  == 0x%08lx\n", vma->vm_start);
     pr_debug("     end user address    == 0x%08lx\n", vma->vm_end);
     pr_debug("     pfn                 == 0x%016lX\n", pfn);
     pr_debug("     vm_flags            == 0x%08lX\n", vma->vm_flags);
     pr_debug("     size                == 0x%08lX\n",
             vma->vm_end - vma->vm_start);
 
     page->user_address = (uint64_t __user *)vma->vm_start;
 
     /* mapping the page to user process */
     ret = remap_pfn_range(vma, vma->vm_start, pfn,
             vma->vm_end - vma->vm_start, vma->vm_page_prot);
     if (!ret)
         p->signal_mapped_size = vma->vm_end - vma->vm_start;
 
     return ret;
 }
 
 /*
  * Assumes that p is not going away.
  */
 static void lookup_events_by_type_and_signal(struct kfd_process *p,
         int type, void *event_data)
 {
     struct kfd_hsa_memory_exception_data *ev_data;
     struct kfd_event *ev;
     uint32_t id;
     bool send_signal = true;
 
     ev_data = (struct kfd_hsa_memory_exception_data *) event_data;
 
     rcu_read_lock();
 
     id = KFD_FIRST_NONSIGNAL_EVENT_ID;
     idr_for_each_entry_continue(&p->event_idr, ev, id)
         if (ev->type == type) {
             send_signal = false;
             dev_dbg(kfd_device,
                     "Event found: id %X type %d",
                     ev->event_id, ev->type);
             spin_lock(&ev->lock);
             set_event(ev);
             if (ev->type == KFD_EVENT_TYPE_MEMORY && ev_data)
                 ev->memory_exception_data = *ev_data;
             spin_unlock(&ev->lock);
         }
 
     if (type == KFD_EVENT_TYPE_MEMORY) {
         dev_warn(kfd_device,
             "Sending SIGSEGV to process %d (pasid 0x%x)",
                 p->lead_thread->pid, p->pasid);
         send_sig(SIGSEGV, p->lead_thread, 0);
     }
 
     /* Send SIGTERM no event of type "type" has been found*/
     if (send_signal) {
         if (send_sigterm) {
             dev_warn(kfd_device,
                 "Sending SIGTERM to process %d (pasid 0x%x)",
                     p->lead_thread->pid, p->pasid);
             send_sig(SIGTERM, p->lead_thread, 0);
         } else {
             dev_err(kfd_device,
                 "Process %d (pasid 0x%x) got unhandled exception",
                 p->lead_thread->pid, p->pasid);
         }
     }
 
     rcu_read_unlock();
 }
 
 #ifdef KFD_SUPPORT_IOMMU_V2
 void kfd_signal_iommu_event(struct kfd_dev *dev, u32 pasid,
         unsigned long address, bool is_write_requested,
         bool is_execute_requested)
 {
     struct kfd_hsa_memory_exception_data memory_exception_data;
     struct vm_area_struct *vma;
     int user_gpu_id;
 
     /*
      * Because we are called from arbitrary context (workqueue) as opposed
      * to process context, kfd_process could attempt to exit while we are
      * running so the lookup function increments the process ref count.
      */
     struct kfd_process *p = kfd_lookup_process_by_pasid(pasid);
     struct mm_struct *mm;
 
     if (!p)
         return; /* Presumably process exited. */
 
     /* Take a safe reference to the mm_struct, which may otherwise
      * disappear even while the kfd_process is still referenced.
      */
     mm = get_task_mm(p->lead_thread);
     if (!mm) {
         kfd_unref_process(p);
         return; /* Process is exiting */
     }
 
     user_gpu_id = kfd_process_get_user_gpu_id(p, dev->id);
     if (unlikely(user_gpu_id == -EINVAL)) {
         WARN_ONCE(1, "Could not get user_gpu_id from dev->id:%x\n", dev->id);
         return;
     }
     memset(&memory_exception_data, 0, sizeof(memory_exception_data));
 
     mmap_read_lock(mm);
     vma = find_vma(mm, address);
 
     memory_exception_data.gpu_id = user_gpu_id;
     memory_exception_data.va = address;
     /* Set failure reason */
     memory_exception_data.failure.NotPresent = 1;
     memory_exception_data.failure.NoExecute = 0;
     memory_exception_data.failure.ReadOnly = 0;
     if (vma && address >= vma->vm_start) {
         memory_exception_data.failure.NotPresent = 0;
 
         if (is_write_requested && !(vma->vm_flags & VM_WRITE))
             memory_exception_data.failure.ReadOnly = 1;
         else
             memory_exception_data.failure.ReadOnly = 0;
 
         if (is_execute_requested && !(vma->vm_flags & VM_EXEC))
             memory_exception_data.failure.NoExecute = 1;
         else
             memory_exception_data.failure.NoExecute = 0;
     }
 
     mmap_read_unlock(mm);
     mmput(mm);
 
     pr_debug("notpresent %d, noexecute %d, readonly %d\n",
             memory_exception_data.failure.NotPresent,
             memory_exception_data.failure.NoExecute,
             memory_exception_data.failure.ReadOnly);
 
     /* Workaround on Raven to not kill the process when memory is freed
      * before IOMMU is able to finish processing all the excessive PPRs
      */
 
     if (KFD_GC_VERSION(dev) != IP_VERSION(9, 1, 0) &&
         KFD_GC_VERSION(dev) != IP_VERSION(9, 2, 2) &&
         KFD_GC_VERSION(dev) != IP_VERSION(9, 3, 0))
         lookup_events_by_type_and_signal(p, KFD_EVENT_TYPE_MEMORY,
                 &memory_exception_data);
 
     kfd_unref_process(p);
 }
 #endif /* KFD_SUPPORT_IOMMU_V2 */
 
 void kfd_signal_hw_exception_event(u32 pasid)
 {
     /*
      * Because we are called from arbitrary context (workqueue) as opposed
      * to process context, kfd_process could attempt to exit while we are
      * running so the lookup function increments the process ref count.
      */
     struct kfd_process *p = kfd_lookup_process_by_pasid(pasid);
 
     if (!p)
         return; /* Presumably process exited. */
 
     lookup_events_by_type_and_signal(p, KFD_EVENT_TYPE_HW_EXCEPTION, NULL);
     kfd_unref_process(p);
 }
 
 void kfd_signal_vm_fault_event(struct kfd_dev *dev, u32 pasid,
                 struct kfd_vm_fault_info *info)
 {
     struct kfd_event *ev;
     uint32_t id;
     struct kfd_process *p = kfd_lookup_process_by_pasid(pasid);
     struct kfd_hsa_memory_exception_data memory_exception_data;
     int user_gpu_id;
 
     if (!p)
         return; /* Presumably process exited. */
 
     user_gpu_id = kfd_process_get_user_gpu_id(p, dev->id);
     if (unlikely(user_gpu_id == -EINVAL)) {
         WARN_ONCE(1, "Could not get user_gpu_id from dev->id:%x\n", dev->id);
         return;
     }
 
     memset(&memory_exception_data, 0, sizeof(memory_exception_data));
     memory_exception_data.gpu_id = user_gpu_id;
     memory_exception_data.failure.imprecise = true;
     /* Set failure reason */
     if (info) {
         memory_exception_data.va = (info->page_addr) << PAGE_SHIFT;
         memory_exception_data.failure.NotPresent =
             info->prot_valid ? 1 : 0;
         memory_exception_data.failure.NoExecute =
             info->prot_exec ? 1 : 0;
         memory_exception_data.failure.ReadOnly =
             info->prot_write ? 1 : 0;
         memory_exception_data.failure.imprecise = 0;
     }
 
     rcu_read_lock();
 
     id = KFD_FIRST_NONSIGNAL_EVENT_ID;
     idr_for_each_entry_continue(&p->event_idr, ev, id)
         if (ev->type == KFD_EVENT_TYPE_MEMORY) {
             spin_lock(&ev->lock);
             ev->memory_exception_data = memory_exception_data;
             set_event(ev);
             spin_unlock(&ev->lock);
         }
 
     rcu_read_unlock();
     kfd_unref_process(p);
 }
 
 void kfd_signal_reset_event(struct kfd_dev *dev)
 {
     struct kfd_hsa_hw_exception_data hw_exception_data;
     struct kfd_hsa_memory_exception_data memory_exception_data;
     struct kfd_process *p;
     struct kfd_event *ev;
     unsigned int temp;
     uint32_t id, idx;
     int reset_cause = atomic_read(&dev->sram_ecc_flag) ?
             KFD_HW_EXCEPTION_ECC :
             KFD_HW_EXCEPTION_GPU_HANG;
 
     /* Whole gpu reset caused by GPU hang and memory is lost */
     memset(&hw_exception_data, 0, sizeof(hw_exception_data));
     hw_exception_data.memory_lost = 1;
     hw_exception_data.reset_cause = reset_cause;
 
     memset(&memory_exception_data, 0, sizeof(memory_exception_data));
     memory_exception_data.ErrorType = KFD_MEM_ERR_SRAM_ECC;
     memory_exception_data.failure.imprecise = true;
 
     idx = srcu_read_lock(&kfd_processes_srcu);
     hash_for_each_rcu(kfd_processes_table, temp, p, kfd_processes) {
         int user_gpu_id = kfd_process_get_user_gpu_id(p, dev->id);
 
         if (unlikely(user_gpu_id == -EINVAL)) {
             WARN_ONCE(1, "Could not get user_gpu_id from dev->id:%x\n", dev->id);
             continue;
         }
 
         rcu_read_lock();
 
         id = KFD_FIRST_NONSIGNAL_EVENT_ID;
         idr_for_each_entry_continue(&p->event_idr, ev, id) {
             if (ev->type == KFD_EVENT_TYPE_HW_EXCEPTION) {
                 spin_lock(&ev->lock);
                 ev->hw_exception_data = hw_exception_data;
                 ev->hw_exception_data.gpu_id = user_gpu_id;
                 set_event(ev);
                 spin_unlock(&ev->lock);
             }
             if (ev->type == KFD_EVENT_TYPE_MEMORY &&
                 reset_cause == KFD_HW_EXCEPTION_ECC) {
                 spin_lock(&ev->lock);
                 ev->memory_exception_data = memory_exception_data;
                 ev->memory_exception_data.gpu_id = user_gpu_id;
                 set_event(ev);
                 spin_unlock(&ev->lock);
             }
         }
 
         rcu_read_unlock();
     }
     srcu_read_unlock(&kfd_processes_srcu, idx);
 }
 
 void kfd_signal_poison_consumed_event(struct kfd_dev *dev, u32 pasid)
 {
     struct kfd_process *p = kfd_lookup_process_by_pasid(pasid);
     struct kfd_hsa_memory_exception_data memory_exception_data;
     struct kfd_hsa_hw_exception_data hw_exception_data;
     struct kfd_event *ev;
     uint32_t id = KFD_FIRST_NONSIGNAL_EVENT_ID;
     int user_gpu_id;
 
     if (!p)
         return; /* Presumably process exited. */
 
     user_gpu_id = kfd_process_get_user_gpu_id(p, dev->id);
     if (unlikely(user_gpu_id == -EINVAL)) {
         WARN_ONCE(1, "Could not get user_gpu_id from dev->id:%x\n", dev->id);
         return;
     }
 
     memset(&hw_exception_data, 0, sizeof(hw_exception_data));
     hw_exception_data.gpu_id = user_gpu_id;
     hw_exception_data.memory_lost = 1;
     hw_exception_data.reset_cause = KFD_HW_EXCEPTION_ECC;
 
     memset(&memory_exception_data, 0, sizeof(memory_exception_data));
     memory_exception_data.ErrorType = KFD_MEM_ERR_POISON_CONSUMED;
     memory_exception_data.gpu_id = user_gpu_id;
     memory_exception_data.failure.imprecise = true;
 
     rcu_read_lock();
 
     idr_for_each_entry_continue(&p->event_idr, ev, id) {
         if (ev->type == KFD_EVENT_TYPE_HW_EXCEPTION) {
             spin_lock(&ev->lock);
             ev->hw_exception_data = hw_exception_data;
             set_event(ev);
             spin_unlock(&ev->lock);
         }
 
         if (ev->type == KFD_EVENT_TYPE_MEMORY) {
             spin_lock(&ev->lock);
             ev->memory_exception_data = memory_exception_data;
             set_event(ev);
             spin_unlock(&ev->lock);
         }
     }
 
     rcu_read_unlock();
 
     /* user application will handle SIGBUS signal */
     send_sig(SIGBUS, p->lead_thread, 0);
 
     kfd_unref_process(p);
 }

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