[PATCH 05/16] drm/i915/vm_bind: Implement bind and unbind of object

Matthew Auld matthew.auld at intel.com
Thu Sep 29 10:51:51 UTC 2022


On 29/09/2022 10:03, Matthew Auld wrote:
> On 29/09/2022 06:24, Niranjana Vishwanathapura wrote:
>> On Wed, Sep 28, 2022 at 06:52:21PM +0100, Matthew Auld wrote:
>>> On 28/09/2022 07:19, Niranjana Vishwanathapura wrote:
>>>> Add uapi and implement support for bind and unbind of an
>>>> object at the specified GPU virtual addresses.
>>>>
>>>> The vm_bind mode is not supported in legacy execbuf2 ioctl.
>>>> It will be supported only in the newer execbuf3 ioctl.
>>>>
>>>> Signed-off-by: Niranjana Vishwanathapura 
>>>> <niranjana.vishwanathapura at intel.com>
>>>> Signed-off-by: Prathap Kumar Valsan <prathap.kumar.valsan at intel.com>
>>>> Signed-off-by: Andi Shyti <andi.shyti at linux.intel.com>
>>>> ---
>>>>  drivers/gpu/drm/i915/Makefile                 |   1 +
>>>>  .../gpu/drm/i915/gem/i915_gem_execbuffer.c    |   5 +
>>>>  drivers/gpu/drm/i915/gem/i915_gem_vm_bind.h   |  26 ++
>>>>  .../drm/i915/gem/i915_gem_vm_bind_object.c    | 306 ++++++++++++++++++
>>>>  drivers/gpu/drm/i915/gt/intel_gtt.c           |  10 +
>>>>  drivers/gpu/drm/i915/gt/intel_gtt.h           |  17 +
>>>>  drivers/gpu/drm/i915/i915_driver.c            |   3 +
>>>>  drivers/gpu/drm/i915/i915_vma.c               |   1 +
>>>>  drivers/gpu/drm/i915/i915_vma_types.h         |  14 +
>>>>  include/uapi/drm/i915_drm.h                   | 112 +++++++
>>>>  10 files changed, 495 insertions(+)
>>>>  create mode 100644 drivers/gpu/drm/i915/gem/i915_gem_vm_bind.h
>>>>  create mode 100644 drivers/gpu/drm/i915/gem/i915_gem_vm_bind_object.c
>>>>
>>>> diff --git a/drivers/gpu/drm/i915/Makefile 
>>>> b/drivers/gpu/drm/i915/Makefile
>>>> index a26edcdadc21..9bf939ef18ea 100644
>>>> --- a/drivers/gpu/drm/i915/Makefile
>>>> +++ b/drivers/gpu/drm/i915/Makefile
>>>> @@ -166,6 +166,7 @@ gem-y += \
>>>>      gem/i915_gem_ttm_move.o \
>>>>      gem/i915_gem_ttm_pm.o \
>>>>      gem/i915_gem_userptr.o \
>>>> +    gem/i915_gem_vm_bind_object.o \
>>>>      gem/i915_gem_wait.o \
>>>>      gem/i915_gemfs.o
>>>>  i915-y += \
>>>> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c 
>>>> b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
>>>> index cd75b0ca2555..f85f10cf9c34 100644
>>>> --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
>>>> +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
>>>> @@ -781,6 +781,11 @@ static int eb_select_context(struct 
>>>> i915_execbuffer *eb)
>>>>      if (unlikely(IS_ERR(ctx)))
>>>>          return PTR_ERR(ctx);
>>>> +    if (ctx->vm->vm_bind_mode) {
>>>> +        i915_gem_context_put(ctx);
>>>> +        return -EOPNOTSUPP;
>>>> +    }
>>>> +
>>>>      eb->gem_context = ctx;
>>>>      if (i915_gem_context_has_full_ppgtt(ctx))
>>>>          eb->invalid_flags |= EXEC_OBJECT_NEEDS_GTT;
>>>> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_vm_bind.h 
>>>> b/drivers/gpu/drm/i915/gem/i915_gem_vm_bind.h
>>>> new file mode 100644
>>>> index 000000000000..36262a6357b5
>>>> --- /dev/null
>>>> +++ b/drivers/gpu/drm/i915/gem/i915_gem_vm_bind.h
>>>> @@ -0,0 +1,26 @@
>>>> +/* SPDX-License-Identifier: MIT */
>>>> +/*
>>>> + * Copyright © 2022 Intel Corporation
>>>> + */
>>>> +
>>>> +#ifndef __I915_GEM_VM_BIND_H
>>>> +#define __I915_GEM_VM_BIND_H
>>>> +
>>>> +#include <linux/types.h>
>>>> +
>>>> +struct drm_device;
>>>> +struct drm_file;
>>>> +struct i915_address_space;
>>>> +struct i915_vma;
>>>> +
>>>> +struct i915_vma *
>>>> +i915_gem_vm_bind_lookup_vma(struct i915_address_space *vm, u64 va);
>>>> +
>>>> +int i915_gem_vm_bind_ioctl(struct drm_device *dev, void *data,
>>>> +               struct drm_file *file);
>>>> +int i915_gem_vm_unbind_ioctl(struct drm_device *dev, void *data,
>>>> +                 struct drm_file *file);
>>>> +
>>>> +void i915_gem_vm_unbind_all(struct i915_address_space *vm);
>>>> +
>>>> +#endif /* __I915_GEM_VM_BIND_H */
>>>> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_vm_bind_object.c 
>>>> b/drivers/gpu/drm/i915/gem/i915_gem_vm_bind_object.c
>>>> new file mode 100644
>>>> index 000000000000..e529162abd2c
>>>> --- /dev/null
>>>> +++ b/drivers/gpu/drm/i915/gem/i915_gem_vm_bind_object.c
>>>> @@ -0,0 +1,306 @@
>>>> +// SPDX-License-Identifier: MIT
>>>> +/*
>>>> + * Copyright © 2022 Intel Corporation
>>>> + */
>>>> +
>>>> +#include <uapi/drm/i915_drm.h>
>>>> +
>>>> +#include <linux/interval_tree_generic.h>
>>>> +
>>>> +#include "gem/i915_gem_context.h"
>>>> +#include "gem/i915_gem_vm_bind.h"
>>>> +
>>>> +#include "gt/intel_gpu_commands.h"
>>>> +
>>>> +#define START(node) ((node)->start)
>>>> +#define LAST(node) ((node)->last)
>>>> +
>>>> +INTERVAL_TREE_DEFINE(struct i915_vma, rb, u64, __subtree_last,
>>>> +             START, LAST, static inline, i915_vm_bind_it)
>>>> +
>>>> +#undef START
>>>> +#undef LAST
>>>> +
>>>> +/**
>>>> + * DOC: VM_BIND/UNBIND ioctls
>>>> + *
>>>> + * DRM_I915_GEM_VM_BIND/UNBIND ioctls allows UMD to bind/unbind GEM 
>>>> buffer
>>>> + * objects (BOs) or sections of a BOs at specified GPU virtual 
>>>> addresses on a
>>>> + * specified address space (VM). Multiple mappings can map to the 
>>>> same physical
>>>> + * pages of an object (aliasing). These mappings (also referred to 
>>>> as persistent
>>>> + * mappings) will be persistent across multiple GPU submissions 
>>>> (execbuf calls)
>>>> + * issued by the UMD, without user having to provide a list of all 
>>>> required
>>>> + * mappings during each submission (as required by older execbuf 
>>>> mode).
>>>> + *
>>>> + * The VM_BIND/UNBIND calls allow UMDs to request a timeline out 
>>>> fence for
>>>> + * signaling the completion of bind/unbind operation.
>>>> + *
>>>> + * VM_BIND feature is advertised to user via 
>>>> I915_PARAM_VM_BIND_VERSION.
>>>> + * User has to opt-in for VM_BIND mode of binding for an address 
>>>> space (VM)
>>>> + * during VM creation time via I915_VM_CREATE_FLAGS_USE_VM_BIND 
>>>> extension.
>>>> + *
>>>> + * VM_BIND/UNBIND ioctl calls executed on different CPU threads 
>>>> concurrently
>>>> + * are not ordered. Furthermore, parts of the VM_BIND/UNBIND 
>>>> operations can be
>>>> + * done asynchronously, when valid out fence is specified.
>>>> + *
>>>> + * VM_BIND locking order is as below.
>>>> + *
>>>> + * 1) vm_bind_lock mutex will protect vm_bind lists. This lock is 
>>>> taken in
>>>> + *    vm_bind/vm_unbind ioctl calls, in the execbuf path and while 
>>>> releasing the
>>>> + *    mapping.
>>>> + *
>>>> + *    In future, when GPU page faults are supported, we can 
>>>> potentially use a
>>>> + *    rwsem instead, so that multiple page fault handlers can take 
>>>> the read
>>>> + *    side lock to lookup the mapping and hence can run in parallel.
>>>> + *    The older execbuf mode of binding do not need this lock.
>>>> + *
>>>> + * 2) The object's dma-resv lock will protect i915_vma state and needs
>>>> + *    to be held while binding/unbinding a vma in the async worker 
>>>> and while
>>>> + *    updating dma-resv fence list of an object. Note that private 
>>>> BOs of a VM
>>>> + *    will all share a dma-resv object.
>>>> + *
>>>> + * 3) Spinlock/s to protect some of the VM's lists like the list of
>>>> + *    invalidated vmas (due to eviction and userptr invalidation) etc.
>>>> + */
>>>> +
>>>> +/**
>>>> + * i915_gem_vm_bind_lookup_vma() - lookup for persistent vma mapped 
>>>> at a
>>>> + * specified address
>>>> + * @vm: virtual address space to look for persistent vma
>>>> + * @va: starting address where vma is mapped
>>>> + *
>>>> + * Retrieves the persistent vma mapped address @va from the @vm's 
>>>> vma tree.
>>>> + *
>>>> + * Returns vma pointer on success, NULL on failure.
>>>> + */
>>>> +struct i915_vma *
>>>> +i915_gem_vm_bind_lookup_vma(struct i915_address_space *vm, u64 va)
>>>> +{
>>>> +    lockdep_assert_held(&vm->vm_bind_lock);
>>>> +
>>>> +    return i915_vm_bind_it_iter_first(&vm->va, va, va);
>>>> +}
>>>> +
>>>> +static void i915_gem_vm_bind_remove(struct i915_vma *vma, bool 
>>>> release_obj)
>>>> +{
>>>> +    lockdep_assert_held(&vma->vm->vm_bind_lock);
>>>> +
>>>> +    list_del_init(&vma->vm_bind_link);
>>>> +    i915_vm_bind_it_remove(vma, &vma->vm->va);
>>>> +
>>>> +    /* Release object */
>>>> +    if (release_obj)
>>>> +        i915_gem_object_put(vma->obj);
>>>> +}
>>>> +
>>>> +static int i915_gem_vm_unbind_vma(struct i915_address_space *vm,
>>>> +                  struct drm_i915_gem_vm_unbind *va)
>>>> +{
>>>> +    struct drm_i915_gem_object *obj;
>>>> +    struct i915_vma *vma;
>>>> +    int ret;
>>>> +
>>>> +    ret = mutex_lock_interruptible(&vm->vm_bind_lock);
>>>> +    if (ret)
>>>> +        return ret;
>>>> +
>>>> +    va->start = gen8_noncanonical_addr(va->start);
>>>> +    vma = i915_gem_vm_bind_lookup_vma(vm, va->start);
>>>> +
>>>> +    if (!vma)
>>>> +        ret = -ENOENT;
>>>> +    else if (vma->size != va->length)
>>>> +        ret = -EINVAL;
>>>> +
>>>> +    if (ret) {
>>>> +        mutex_unlock(&vm->vm_bind_lock);
>>>> +        return ret;
>>>> +    }
>>>> +
>>>> +    i915_gem_vm_bind_remove(vma, false);
>>>> +
>>>> +    mutex_unlock(&vm->vm_bind_lock);
>>>> +
>>>> +    /* Destroy vma and then release object */
>>>> +    obj = vma->obj;
>>>> +    ret = i915_gem_object_lock(obj, NULL);
>>>> +    if (ret)
>>>> +        return ret;
>>>> +
>>>> +    i915_vma_destroy(vma);
>>>> +    i915_gem_object_unlock(obj);
>>>> +
>>>> +    i915_gem_object_put(obj);
>>>> +
>>>> +    return 0;
>>>> +}
>>>> +
>>>> +/**
>>>> + * i915_gem_vm_unbind_all() - unbind all persistent mappings from an
>>>> + * address space
>>>> + * @vm: Address spece to remove persistent mappings from
>>>> + *
>>>> + * Unbind all userspace requested vm_bind mappings from @vm.
>>>> + */
>>>> +void i915_gem_vm_unbind_all(struct i915_address_space *vm)
>>>> +{
>>>> +    struct i915_vma *vma, *t;
>>>> +
>>>> +    mutex_lock(&vm->vm_bind_lock);
>>>> +    list_for_each_entry_safe(vma, t, &vm->vm_bind_list, vm_bind_link)
>>>> +        i915_gem_vm_bind_remove(vma, true);
>>>> +    list_for_each_entry_safe(vma, t, &vm->vm_bound_list, vm_bind_link)
>>>> +        i915_gem_vm_bind_remove(vma, true);
>>>> +    mutex_unlock(&vm->vm_bind_lock);
>>>> +}
>>>> +
>>>> +static struct i915_vma *vm_bind_get_vma(struct i915_address_space *vm,
>>>> +                    struct drm_i915_gem_object *obj,
>>>> +                    struct drm_i915_gem_vm_bind *va)
>>>> +{
>>>> +    struct i915_gtt_view view;
>>>> +    struct i915_vma *vma;
>>>> +
>>>> +    va->start = gen8_noncanonical_addr(va->start);
>>>> +    vma = i915_gem_vm_bind_lookup_vma(vm, va->start);
>>>> +    if (vma)
>>>> +        return ERR_PTR(-EEXIST);
>>>> +
>>>> +    view.type = I915_GTT_VIEW_PARTIAL;
>>>> +    view.partial.offset = va->offset >> PAGE_SHIFT;
>>>> +    view.partial.size = va->length >> PAGE_SHIFT;
>>>> +    vma = i915_vma_create_persistent(obj, vm, &view);
>>>> +    if (IS_ERR(vma))
>>>> +        return vma;
>>>> +
>>>> +    vma->start = va->start;
>>>> +    vma->last = va->start + va->length - 1;
>>>> +
>>>> +    return vma;
>>>> +}
>>>> +
>>>> +static int i915_gem_vm_bind_obj(struct i915_address_space *vm,
>>>> +                struct drm_i915_gem_vm_bind *va,
>>>> +                struct drm_file *file)
>>>> +{
>>>> +    struct drm_i915_gem_object *obj;
>>>> +    struct i915_vma *vma = NULL;
>>>> +    struct i915_gem_ww_ctx ww;
>>>> +    u64 pin_flags;
>>>> +    int ret = 0;
>>>> +
>>>> +    if (!vm->vm_bind_mode)
>>>> +        return -EOPNOTSUPP;
>>>> +
>>>> +    obj = i915_gem_object_lookup(file, va->handle);
>>>> +    if (!obj)
>>>> +        return -ENOENT;
>>>> +
>>>> +    if (!va->length ||
>>>> +        !IS_ALIGNED(va->offset | va->length,
>>>> +            i915_gem_object_max_page_size(obj->mm.placements,
>>>> +                              obj->mm.n_placements)) ||
>>>> +        range_overflows_t(u64, va->offset, va->length, 
>>>> obj->base.size)) {
>>>> +        ret = -EINVAL;
>>>> +        goto put_obj;
>>>> +    }
>>>> +
>>>> +    ret = mutex_lock_interruptible(&vm->vm_bind_lock);
>>>> +    if (ret)
>>>> +        goto put_obj;
>>>> +
>>>> +    vma = vm_bind_get_vma(vm, obj, va);
>>>> +    if (IS_ERR(vma)) {
>>>> +        ret = PTR_ERR(vma);
>>>> +        goto unlock_vm;
>>>> +    }
>>>> +
>>>> +    pin_flags = va->start | PIN_OFFSET_FIXED | PIN_USER;
>>>> +
>>>> +    for_i915_gem_ww(&ww, ret, true) {
>>>> +        ret = i915_gem_object_lock(vma->obj, &ww);
>>>> +        if (ret)
>>>> +            continue;
>>>> +
>>>> +        ret = i915_vma_pin_ww(vma, &ww, 0, 0, pin_flags);
>>>> +        if (ret)
>>>> +            continue;
>>>> +
>>>> +        /* Make it evictable */
>>>> +        __i915_vma_unpin(vma);
>>>> +
>>>> +        list_add_tail(&vma->vm_bind_link, &vm->vm_bound_list);
>>>> +        i915_vm_bind_it_insert(vma, &vm->va);
>>>> +
>>>> +        /* Hold object reference until vm_unbind */
>>>> +        i915_gem_object_get(vma->obj);
>>>> +    }
>>>> +
>>>> +    if (ret)
>>>> +        i915_vma_destroy(vma);
>>>> +unlock_vm:
>>>> +    mutex_unlock(&vm->vm_bind_lock);
>>>> +put_obj:
>>>> +    i915_gem_object_put(obj);
>>>> +
>>>> +    return ret;
>>>> +}
>>>> +
>>>> +/**
>>>> + * i915_gem_vm_bind_ioctl() - ioctl function for binding a section 
>>>> of object
>>>> + * at a specified virtual address
>>>> + * @dev: drm_device pointer
>>>> + * @data: ioctl data structure
>>>> + * @file: drm_file pointer
>>>> + *
>>>> + * Adds the specified persistent mapping (virtual address to a 
>>>> section of an
>>>> + * object) and binds it in the device page table.
>>>> + *
>>>> + * Returns 0 on success, error code on failure.
>>>> + */
>>>> +int i915_gem_vm_bind_ioctl(struct drm_device *dev, void *data,
>>>> +               struct drm_file *file)
>>>> +{
>>>> +    struct drm_i915_gem_vm_bind *args = data;
>>>> +    struct i915_address_space *vm;
>>>> +    int ret;
>>>> +
>>>> +    vm = i915_gem_vm_lookup(file->driver_priv, args->vm_id);
>>>> +    if (unlikely(!vm))
>>>> +        return -ENOENT;
>>>> +
>>>> +    ret = i915_gem_vm_bind_obj(vm, args, file);
>>>> +
>>>> +    i915_vm_put(vm);
>>>> +    return ret;
>>>> +}
>>>> +
>>>> +/**
>>>> + * i915_gem_vm_unbind_ioctl() - ioctl function for unbinding a 
>>>> mapping at a
>>>> + * specified virtual address
>>>> + * @dev: drm_device pointer
>>>> + * @data: ioctl data structure
>>>> + * @file: drm_file pointer
>>>> + *
>>>> + * Removes the persistent mapping at the specified address and 
>>>> unbinds it
>>>> + * from the device page table.
>>>> + *
>>>> + * Returns 0 on success, error code on failure. -ENOENT is returned 
>>>> if the
>>>> + * specified mapping is not found.
>>>> + */
>>>> +int i915_gem_vm_unbind_ioctl(struct drm_device *dev, void *data,
>>>> +                 struct drm_file *file)
>>>> +{
>>>> +    struct drm_i915_gem_vm_unbind *args = data;
>>>> +    struct i915_address_space *vm;
>>>> +    int ret;
>>>> +
>>>> +    vm = i915_gem_vm_lookup(file->driver_priv, args->vm_id);
>>>> +    if (unlikely(!vm))
>>>> +        return -ENOENT;
>>>> +
>>>> +    ret = i915_gem_vm_unbind_vma(vm, args);
>>>> +
>>>> +    i915_vm_put(vm);
>>>> +    return ret;
>>>> +}
>>>> diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.c 
>>>> b/drivers/gpu/drm/i915/gt/intel_gtt.c
>>>> index b67831833c9a..0daa70c6ed0d 100644
>>>> --- a/drivers/gpu/drm/i915/gt/intel_gtt.c
>>>> +++ b/drivers/gpu/drm/i915/gt/intel_gtt.c
>>>> @@ -12,6 +12,7 @@
>>>>  #include "gem/i915_gem_internal.h"
>>>>  #include "gem/i915_gem_lmem.h"
>>>> +#include "gem/i915_gem_vm_bind.h"
>>>>  #include "i915_trace.h"
>>>>  #include "i915_utils.h"
>>>>  #include "intel_gt.h"
>>>> @@ -176,6 +177,8 @@ int i915_vm_lock_objects(struct 
>>>> i915_address_space *vm,
>>>>  void i915_address_space_fini(struct i915_address_space *vm)
>>>>  {
>>>>      drm_mm_takedown(&vm->mm);
>>>> +    GEM_BUG_ON(!RB_EMPTY_ROOT(&vm->va.rb_root));
>>>> +    mutex_destroy(&vm->vm_bind_lock);
>>>>  }
>>>>  /**
>>>> @@ -202,6 +205,8 @@ static void __i915_vm_release(struct work_struct 
>>>> *work)
>>>>      struct i915_address_space *vm =
>>>>          container_of(work, struct i915_address_space, release_work);
>>>> +    i915_gem_vm_unbind_all(vm);
>>>> +
>>>>      __i915_vm_close(vm);
>>>>      /* Synchronize async unbinds. */
>>>> @@ -282,6 +287,11 @@ void i915_address_space_init(struct 
>>>> i915_address_space *vm, int subclass)
>>>>      INIT_LIST_HEAD(&vm->bound_list);
>>>>      INIT_LIST_HEAD(&vm->unbound_list);
>>>> +
>>>> +    vm->va = RB_ROOT_CACHED;
>>>> +    INIT_LIST_HEAD(&vm->vm_bind_list);
>>>> +    INIT_LIST_HEAD(&vm->vm_bound_list);
>>>> +    mutex_init(&vm->vm_bind_lock);
>>>>  }
>>>>  void *__px_vaddr(struct drm_i915_gem_object *p)
>>>> diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.h 
>>>> b/drivers/gpu/drm/i915/gt/intel_gtt.h
>>>> index c0ca53cba9f0..b52061858161 100644
>>>> --- a/drivers/gpu/drm/i915/gt/intel_gtt.h
>>>> +++ b/drivers/gpu/drm/i915/gt/intel_gtt.h
>>>> @@ -259,6 +259,23 @@ struct i915_address_space {
>>>>       */
>>>>      struct list_head unbound_list;
>>>> +    /**
>>>> +     * @vm_bind_mode: flag to indicate vm_bind method of binding
>>>> +     *
>>>> +     * True: allow only vm_bind method of binding.
>>>> +     * False: allow only legacy execbuff method of binding.
>>>> +     */
>>>> +    bool vm_bind_mode:1;
>>>> +
>>>> +    /** @vm_bind_lock: Mutex to protect @vm_bind_list and 
>>>> @vm_bound_list */
>>>> +    struct mutex vm_bind_lock;
>>>> +    /** @vm_bind_list: List of vm_binding in process */
>>>> +    struct list_head vm_bind_list;
>>>> +    /** @vm_bound_list: List of vm_binding completed */
>>>> +    struct list_head vm_bound_list;
>>>> +    /* @va: tree of persistent vmas */
>>>> +    struct rb_root_cached va;
>>>> +
>>>>      /* Global GTT */
>>>>      bool is_ggtt:1;
>>>> diff --git a/drivers/gpu/drm/i915/i915_driver.c 
>>>> b/drivers/gpu/drm/i915/i915_driver.c
>>>> index fb3826dabe8b..c3a9a5031cdb 100644
>>>> --- a/drivers/gpu/drm/i915/i915_driver.c
>>>> +++ b/drivers/gpu/drm/i915/i915_driver.c
>>>> @@ -69,6 +69,7 @@
>>>>  #include "gem/i915_gem_ioctls.h"
>>>>  #include "gem/i915_gem_mman.h"
>>>>  #include "gem/i915_gem_pm.h"
>>>> +#include "gem/i915_gem_vm_bind.h"
>>>>  #include "gt/intel_gt.h"
>>>>  #include "gt/intel_gt_pm.h"
>>>>  #include "gt/intel_rc6.h"
>>>> @@ -1893,6 +1894,8 @@ static const struct drm_ioctl_desc 
>>>> i915_ioctls[] = {
>>>>      DRM_IOCTL_DEF_DRV(I915_QUERY, i915_query_ioctl, DRM_RENDER_ALLOW),
>>>>      DRM_IOCTL_DEF_DRV(I915_GEM_VM_CREATE, i915_gem_vm_create_ioctl, 
>>>> DRM_RENDER_ALLOW),
>>>>      DRM_IOCTL_DEF_DRV(I915_GEM_VM_DESTROY, 
>>>> i915_gem_vm_destroy_ioctl, DRM_RENDER_ALLOW),
>>>> +    DRM_IOCTL_DEF_DRV(I915_GEM_VM_BIND, i915_gem_vm_bind_ioctl, 
>>>> DRM_RENDER_ALLOW),
>>>> +    DRM_IOCTL_DEF_DRV(I915_GEM_VM_UNBIND, i915_gem_vm_unbind_ioctl, 
>>>> DRM_RENDER_ALLOW),
>>>>  };
>>>>  /*
>>>> diff --git a/drivers/gpu/drm/i915/i915_vma.c 
>>>> b/drivers/gpu/drm/i915/i915_vma.c
>>>> index 5839e1f55f00..33f910473263 100644
>>>> --- a/drivers/gpu/drm/i915/i915_vma.c
>>>> +++ b/drivers/gpu/drm/i915/i915_vma.c
>>>> @@ -239,6 +239,7 @@ vma_create(struct drm_i915_gem_object *obj,
>>>>      spin_unlock(&obj->vma.lock);
>>>>      mutex_unlock(&vm->mutex);
>>>> +    INIT_LIST_HEAD(&vma->vm_bind_link);
>>>>      return vma;
>>>>  err_unlock:
>>>> diff --git a/drivers/gpu/drm/i915/i915_vma_types.h 
>>>> b/drivers/gpu/drm/i915/i915_vma_types.h
>>>> index 2200f1f103ba..f56ac07c6cfa 100644
>>>> --- a/drivers/gpu/drm/i915/i915_vma_types.h
>>>> +++ b/drivers/gpu/drm/i915/i915_vma_types.h
>>>> @@ -296,6 +296,20 @@ struct i915_vma {
>>>>      /** This object's place on the active/inactive lists */
>>>>      struct list_head vm_link;
>>>> +    /** @vm_bind_link: node for the vm_bind related lists of vm */
>>>> +    struct list_head vm_bind_link;
>>>> +
>>>> +    /** Interval tree structures for persistent vma */
>>>> +
>>>> +    /** @rb: node for the interval tree of vm for persistent vmas */
>>>> +    struct rb_node rb;
>>>> +    /** @start: start endpoint of the rb node */
>>>> +    u64 start;
>>>> +    /** @last: Last endpoint of the rb node */
>>>> +    u64 last;
>>>> +    /** @__subtree_last: last in subtree */
>>>> +    u64 __subtree_last;
>>>> +
>>>>      struct list_head obj_link; /* Link in the object's VMA list */
>>>>      struct rb_node obj_node;
>>>>      struct hlist_node obj_hash;
>>>> diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
>>>> index 520ad2691a99..9760564b4693 100644
>>>> --- a/include/uapi/drm/i915_drm.h
>>>> +++ b/include/uapi/drm/i915_drm.h
>>>> @@ -470,6 +470,8 @@ typedef struct _drm_i915_sarea {
>>>>  #define DRM_I915_GEM_VM_CREATE        0x3a
>>>>  #define DRM_I915_GEM_VM_DESTROY        0x3b
>>>>  #define DRM_I915_GEM_CREATE_EXT        0x3c
>>>> +#define DRM_I915_GEM_VM_BIND        0x3d
>>>> +#define DRM_I915_GEM_VM_UNBIND        0x3e
>>>>  /* Must be kept compact -- no holes */
>>>>  #define DRM_IOCTL_I915_INIT        DRM_IOW( DRM_COMMAND_BASE + 
>>>> DRM_I915_INIT, drm_i915_init_t)
>>>> @@ -534,6 +536,8 @@ typedef struct _drm_i915_sarea {
>>>>  #define DRM_IOCTL_I915_QUERY            DRM_IOWR(DRM_COMMAND_BASE + 
>>>> DRM_I915_QUERY, struct drm_i915_query)
>>>>  #define DRM_IOCTL_I915_GEM_VM_CREATE    DRM_IOWR(DRM_COMMAND_BASE + 
>>>> DRM_I915_GEM_VM_CREATE, struct drm_i915_gem_vm_control)
>>>>  #define DRM_IOCTL_I915_GEM_VM_DESTROY    DRM_IOW (DRM_COMMAND_BASE 
>>>> + DRM_I915_GEM_VM_DESTROY, struct drm_i915_gem_vm_control)
>>>> +#define DRM_IOCTL_I915_GEM_VM_BIND    DRM_IOWR(DRM_COMMAND_BASE + 
>>>> DRM_I915_GEM_VM_BIND, struct drm_i915_gem_vm_bind)
>>>> +#define DRM_IOCTL_I915_GEM_VM_UNBIND    DRM_IOWR(DRM_COMMAND_BASE + 
>>>> DRM_I915_GEM_VM_UNBIND, struct drm_i915_gem_vm_unbind)
>>>>  /* Allow drivers to submit batchbuffers directly to hardware, relying
>>>>   * on the security mechanisms provided by hardware.
>>>> @@ -3717,6 +3721,114 @@ struct 
>>>> drm_i915_gem_create_ext_protected_content {
>>>>  /* ID of the protected content session managed by i915 when PXP is 
>>>> active */
>>>>  #define I915_PROTECTED_CONTENT_DEFAULT_SESSION 0xf
>>>> +/**
>>>> + * struct drm_i915_gem_vm_bind - VA to object mapping to bind.
>>>> + *
>>>> + * This structure is passed to VM_BIND ioctl and specifies the 
>>>> mapping of GPU
>>>> + * virtual address (VA) range to the section of an object that 
>>>> should be bound
>>>> + * in the device page table of the specified address space (VM).
>>>> + * The VA range specified must be unique (ie., not currently bound) 
>>>> and can
>>>> + * be mapped to whole object or a section of the object (partial 
>>>> binding).
>>>> + * Multiple VA mappings can be created to the same section of the 
>>>> object
>>>> + * (aliasing).
>>>> + *
>>>> + * The @start, @offset and @length must be 4K page aligned. However 
>>>> the DG2
>>>> + * and XEHPSDV has 64K page size for device local memory and has 
>>>> compact page
>>>> + * table. On those platforms, for binding device local-memory 
>>>> objects, the
>>>> + * @start, @offset and @length must be 64K aligned. Also, UMDs 
>>>> should not mix
>>>> + * the local memory 64K page and the system memory 4K page bindings 
>>>> in the same
>>>> + * 2M range.
>>>
>>> This is hopefully no longer the case if we land:
>>> https://patchwork.freedesktop.org/series/109126/
>>>
>>> Should only need 64K alignment, and mixing should be fine now, which 
>>> should be a lot nicer. Hopefully doesn't really impact your series, 
>>> other than just updating the comment here?
>>>
>>
>> Oh great. Will remove the last sentence then.
>> Yah, we just need to remove the extra comment here.
>>
>>>> + *
>>>> + * Error code -EINVAL will be returned if @start, @offset and 
>>>> @length are not
>>>> + * properly aligned. In version 1 (See I915_PARAM_VM_BIND_VERSION), 
>>>> error code
>>>> + * -ENOSPC will be returned if the VA range specified can't be 
>>>> reserved.
>>>> + *
>>>> + * VM_BIND/UNBIND ioctl calls executed on different CPU threads 
>>>> concurrently
>>>> + * are not ordered. Furthermore, parts of the VM_BIND operation can 
>>>> be done
>>>> + * asynchronously, if valid @fence is specified.
>>>> + */
>>>> +struct drm_i915_gem_vm_bind {
>>>> +    /** @vm_id: VM (address space) id to bind */
>>>> +    __u32 vm_id;
>>>> +
>>>> +    /** @handle: Object handle */
>>>> +    __u32 handle;
>>>> +
>>>> +    /** @start: Virtual Address start to bind */
>>>> +    __u64 start;
>>>> +
>>>> +    /** @offset: Offset in object to bind */
>>>> +    __u64 offset;
>>>> +
>>>> +    /** @length: Length of mapping to bind */
>>>> +    __u64 length;
>>>> +
>>>> +    /**
>>>> +     * @flags: Currently reserved, MBZ.
>>>> +     *
>>>> +     * Note that @fence carries its own flags.
>>>> +     */
>>>> +    __u64 flags;
>>>> +
>>>> +    /** @rsvd: Reserved, MBZ */
>>>> +    __u64 rsvd[2];
>>>
>>> There is lots of rsvd stuff here and below, but I don't see where we 
>>> are verifying if it is actually MBZ?
>>>
>>
>> These rsvd fields are temporary and is replaced by a later patch in
>> the series. However, the rsvd field in vm_unbind structure below is
>> needed and I will update the code to check for 0.
> 
> Ideally each patch by itself should be functional, so here we should 
> check the padding, and then later remove the checks for the additional 
> functionally. Or just keep the ioctls(s) disabled (return -ENODEV or so) 
> at this point in the series, and then have the last patch in the series 
> turn on the vm_bind support by removing the -ENODEV guards.

It looks like that is maybe already the case as per the final patch: 
"Add uapi for user to enable vm_bind_mode"?

> 
>>
>> Regards,
>> Niranjana
>>
>>>> +
>>>> +    /**
>>>> +     * @extensions: Zero-terminated chain of extensions.
>>>> +     *
>>>> +     * For future extensions. See struct i915_user_extension.
>>>> +     */
>>>> +    __u64 extensions;
>>>> +};
>>>> +
>>>> +/**
>>>> + * struct drm_i915_gem_vm_unbind - VA to object mapping to unbind.
>>>> + *
>>>> + * This structure is passed to VM_UNBIND ioctl and specifies the 
>>>> GPU virtual
>>>> + * address (VA) range that should be unbound from the device page 
>>>> table of the
>>>> + * specified address space (VM). VM_UNBIND will force unbind the 
>>>> specified
>>>> + * range from device page table without waiting for any GPU job to 
>>>> complete.
>>>> + * It is UMDs responsibility to ensure the mapping is no longer in 
>>>> use before
>>>> + * calling VM_UNBIND.
>>>> + *
>>>> + * If the specified mapping is not found, the ioctl will simply 
>>>> return without
>>>> + * any error.
>>>> + *
>>>> + * VM_BIND/UNBIND ioctl calls executed on different CPU threads 
>>>> concurrently
>>>> + * are not ordered. Furthermore, parts of the VM_UNBIND operation 
>>>> can be done
>>>> + * asynchronously, if valid @fence is specified.
>>>> + */
>>>> +struct drm_i915_gem_vm_unbind {
>>>> +    /** @vm_id: VM (address space) id to bind */
>>>> +    __u32 vm_id;
>>>> +
>>>> +    /** @rsvd: Reserved, MBZ */
>>>> +    __u32 rsvd;
>>>> +
>>>> +    /** @start: Virtual Address start to unbind */
>>>> +    __u64 start;
>>>> +
>>>> +    /** @length: Length of mapping to unbind */
>>>> +    __u64 length;
>>>> +
>>>> +    /**
>>>> +     * @flags: Currently reserved, MBZ.
>>>> +     *
>>>> +     * Note that @fence carries its own flags.
>>>> +     */
>>>> +    __u64 flags;
>>>> +
>>>> +    /** @rsvd2: Reserved, MBZ */
>>>> +    __u64 rsvd2[2];
>>>> +
>>>> +    /**
>>>> +     * @extensions: Zero-terminated chain of extensions.
>>>> +     *
>>>> +     * For future extensions. See struct i915_user_extension.
>>>> +     */
>>>> +    __u64 extensions;
>>>> +};
>>>> +
>>>>  #if defined(__cplusplus)
>>>>  }
>>>>  #endif


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