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linuxdebug/drivers/gpu/drm/i915/gem/i915_gem_context.c

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null pointer error
2024-07-16 15:50:57 +02:00
/*
* SPDX-License-Identifier: MIT
*
* Copyright © 2011-2012 Intel Corporation
*/
/*
* This file implements HW context support. On gen5+ a HW context consists of an
* opaque GPU object which is referenced at times of context saves and restores.
* With RC6 enabled, the context is also referenced as the GPU enters and exists
* from RC6 (GPU has it's own internal power context, except on gen5). Though
* something like a context does exist for the media ring, the code only
* supports contexts for the render ring.
*
* In software, there is a distinction between contexts created by the user,
* and the default HW context. The default HW context is used by GPU clients
* that do not request setup of their own hardware context. The default
* context's state is never restored to help prevent programming errors. This
* would happen if a client ran and piggy-backed off another clients GPU state.
* The default context only exists to give the GPU some offset to load as the
* current to invoke a save of the context we actually care about. In fact, the
* code could likely be constructed, albeit in a more complicated fashion, to
* never use the default context, though that limits the driver's ability to
* swap out, and/or destroy other contexts.
*
* All other contexts are created as a request by the GPU client. These contexts
* store GPU state, and thus allow GPU clients to not re-emit state (and
* potentially query certain state) at any time. The kernel driver makes
* certain that the appropriate commands are inserted.
*
* The context life cycle is semi-complicated in that context BOs may live
* longer than the context itself because of the way the hardware, and object
* tracking works. Below is a very crude representation of the state machine
* describing the context life.
* refcount pincount active
* S0: initial state 0 0 0
* S1: context created 1 0 0
* S2: context is currently running 2 1 X
* S3: GPU referenced, but not current 2 0 1
* S4: context is current, but destroyed 1 1 0
* S5: like S3, but destroyed 1 0 1
*
* The most common (but not all) transitions:
* S0->S1: client creates a context
* S1->S2: client submits execbuf with context
* S2->S3: other clients submits execbuf with context
* S3->S1: context object was retired
* S3->S2: clients submits another execbuf
* S2->S4: context destroy called with current context
* S3->S5->S0: destroy path
* S4->S5->S0: destroy path on current context
*
* There are two confusing terms used above:
* The "current context" means the context which is currently running on the
* GPU. The GPU has loaded its state already and has stored away the gtt
* offset of the BO. The GPU is not actively referencing the data at this
* offset, but it will on the next context switch. The only way to avoid this
* is to do a GPU reset.
*
* An "active context' is one which was previously the "current context" and is
* on the active list waiting for the next context switch to occur. Until this
* happens, the object must remain at the same gtt offset. It is therefore
* possible to destroy a context, but it is still active.
*
*/
#include <linux/highmem.h>
#include <linux/log2.h>
#include <linux/nospec.h>
#include <drm/drm_cache.h>
#include <drm/drm_syncobj.h>
#include "gt/gen6_ppgtt.h"
#include "gt/intel_context.h"
#include "gt/intel_context_param.h"
#include "gt/intel_engine_heartbeat.h"
#include "gt/intel_engine_user.h"
#include "gt/intel_gpu_commands.h"
#include "gt/intel_ring.h"
#include "pxp/intel_pxp.h"
#include "i915_file_private.h"
#include "i915_gem_context.h"
#include "i915_trace.h"
#include "i915_user_extensions.h"
#define ALL_L3_SLICES(dev) (1 << NUM_L3_SLICES(dev)) - 1
static struct kmem_cache *slab_luts;
struct i915_lut_handle *i915_lut_handle_alloc(void)
{
return kmem_cache_alloc(slab_luts, GFP_KERNEL);
}
void i915_lut_handle_free(struct i915_lut_handle *lut)
{
return kmem_cache_free(slab_luts, lut);
}
static void lut_close(struct i915_gem_context *ctx)
{
struct radix_tree_iter iter;
void __rcu **slot;
mutex_lock(&ctx->lut_mutex);
rcu_read_lock();
radix_tree_for_each_slot(slot, &ctx->handles_vma, &iter, 0) {
struct i915_vma *vma = rcu_dereference_raw(*slot);
struct drm_i915_gem_object *obj = vma->obj;
struct i915_lut_handle *lut;
if (!kref_get_unless_zero(&obj->base.refcount))
continue;
spin_lock(&obj->lut_lock);
list_for_each_entry(lut, &obj->lut_list, obj_link) {
if (lut->ctx != ctx)
continue;
if (lut->handle != iter.index)
continue;
list_del(&lut->obj_link);
break;
}
spin_unlock(&obj->lut_lock);
if (&lut->obj_link != &obj->lut_list) {
i915_lut_handle_free(lut);
radix_tree_iter_delete(&ctx->handles_vma, &iter, slot);
i915_vma_close(vma);
i915_gem_object_put(obj);
}
i915_gem_object_put(obj);
}
rcu_read_unlock();
mutex_unlock(&ctx->lut_mutex);
}
static struct intel_context *
lookup_user_engine(struct i915_gem_context *ctx,
unsigned long flags,
const struct i915_engine_class_instance *ci)
#define LOOKUP_USER_INDEX BIT(0)
{
int idx;
if (!!(flags & LOOKUP_USER_INDEX) != i915_gem_context_user_engines(ctx))
return ERR_PTR(-EINVAL);
if (!i915_gem_context_user_engines(ctx)) {
struct intel_engine_cs *engine;
engine = intel_engine_lookup_user(ctx->i915,
ci->engine_class,
ci->engine_instance);
if (!engine)
return ERR_PTR(-EINVAL);
idx = engine->legacy_idx;
} else {
idx = ci->engine_instance;
}
return i915_gem_context_get_engine(ctx, idx);
}
static int validate_priority(struct drm_i915_private *i915,
const struct drm_i915_gem_context_param *args)
{
s64 priority = args->value;
if (args->size)
return -EINVAL;
if (!(i915->caps.scheduler & I915_SCHEDULER_CAP_PRIORITY))
return -ENODEV;
if (priority > I915_CONTEXT_MAX_USER_PRIORITY ||
priority < I915_CONTEXT_MIN_USER_PRIORITY)
return -EINVAL;
if (priority > I915_CONTEXT_DEFAULT_PRIORITY &&
!capable(CAP_SYS_NICE))
return -EPERM;
return 0;
}
static void proto_context_close(struct drm_i915_private *i915,
struct i915_gem_proto_context *pc)
{
int i;
if (pc->pxp_wakeref)
intel_runtime_pm_put(&i915->runtime_pm, pc->pxp_wakeref);
if (pc->vm)
i915_vm_put(pc->vm);
if (pc->user_engines) {
for (i = 0; i < pc->num_user_engines; i++)
kfree(pc->user_engines[i].siblings);
kfree(pc->user_engines);
}
kfree(pc);
}
static int proto_context_set_persistence(struct drm_i915_private *i915,
struct i915_gem_proto_context *pc,
bool persist)
{
if (persist) {
/*
* Only contexts that are short-lived [that will expire or be
* reset] are allowed to survive past termination. We require
* hangcheck to ensure that the persistent requests are healthy.
*/
if (!i915->params.enable_hangcheck)
return -EINVAL;
pc->user_flags |= BIT(UCONTEXT_PERSISTENCE);
} else {
/* To cancel a context we use "preempt-to-idle" */
if (!(i915->caps.scheduler & I915_SCHEDULER_CAP_PREEMPTION))
return -ENODEV;
/*
* If the cancel fails, we then need to reset, cleanly!
*
* If the per-engine reset fails, all hope is lost! We resort
* to a full GPU reset in that unlikely case, but realistically
* if the engine could not reset, the full reset does not fare
* much better. The damage has been done.
*
* However, if we cannot reset an engine by itself, we cannot
* cleanup a hanging persistent context without causing
* colateral damage, and we should not pretend we can by
* exposing the interface.
*/
if (!intel_has_reset_engine(to_gt(i915)))
return -ENODEV;
pc->user_flags &= ~BIT(UCONTEXT_PERSISTENCE);
}
return 0;
}
static int proto_context_set_protected(struct drm_i915_private *i915,
struct i915_gem_proto_context *pc,
bool protected)
{
int ret = 0;
if (!protected) {
pc->uses_protected_content = false;
} else if (!intel_pxp_is_enabled(&to_gt(i915)->pxp)) {
ret = -ENODEV;
} else if ((pc->user_flags & BIT(UCONTEXT_RECOVERABLE)) ||
!(pc->user_flags & BIT(UCONTEXT_BANNABLE))) {
ret = -EPERM;
} else {
pc->uses_protected_content = true;
/*
* protected context usage requires the PXP session to be up,
* which in turn requires the device to be active.
*/
pc->pxp_wakeref = intel_runtime_pm_get(&i915->runtime_pm);
if (!intel_pxp_is_active(&to_gt(i915)->pxp))
ret = intel_pxp_start(&to_gt(i915)->pxp);
}
return ret;
}
static struct i915_gem_proto_context *
proto_context_create(struct drm_i915_private *i915, unsigned int flags)
{
struct i915_gem_proto_context *pc, *err;
pc = kzalloc(sizeof(*pc), GFP_KERNEL);
if (!pc)
return ERR_PTR(-ENOMEM);
pc->num_user_engines = -1;
pc->user_engines = NULL;
pc->user_flags = BIT(UCONTEXT_BANNABLE) |
BIT(UCONTEXT_RECOVERABLE);
if (i915->params.enable_hangcheck)
pc->user_flags |= BIT(UCONTEXT_PERSISTENCE);
pc->sched.priority = I915_PRIORITY_NORMAL;
if (flags & I915_CONTEXT_CREATE_FLAGS_SINGLE_TIMELINE) {
if (!HAS_EXECLISTS(i915)) {
err = ERR_PTR(-EINVAL);
goto proto_close;
}
pc->single_timeline = true;
}
return pc;
proto_close:
proto_context_close(i915, pc);
return err;
}
static int proto_context_register_locked(struct drm_i915_file_private *fpriv,
struct i915_gem_proto_context *pc,
u32 *id)
{
int ret;
void *old;
lockdep_assert_held(&fpriv->proto_context_lock);
ret = xa_alloc(&fpriv->context_xa, id, NULL, xa_limit_32b, GFP_KERNEL);
if (ret)
return ret;
old = xa_store(&fpriv->proto_context_xa, *id, pc, GFP_KERNEL);
if (xa_is_err(old)) {
xa_erase(&fpriv->context_xa, *id);
return xa_err(old);
}
WARN_ON(old);
return 0;
}
static int proto_context_register(struct drm_i915_file_private *fpriv,
struct i915_gem_proto_context *pc,
u32 *id)
{
int ret;
mutex_lock(&fpriv->proto_context_lock);
ret = proto_context_register_locked(fpriv, pc, id);
mutex_unlock(&fpriv->proto_context_lock);
return ret;
}
static struct i915_address_space *
i915_gem_vm_lookup(struct drm_i915_file_private *file_priv, u32 id)
{
struct i915_address_space *vm;
xa_lock(&file_priv->vm_xa);
vm = xa_load(&file_priv->vm_xa, id);
if (vm)
kref_get(&vm->ref);
xa_unlock(&file_priv->vm_xa);
return vm;
}
static int set_proto_ctx_vm(struct drm_i915_file_private *fpriv,
struct i915_gem_proto_context *pc,
const struct drm_i915_gem_context_param *args)
{
struct drm_i915_private *i915 = fpriv->dev_priv;
struct i915_address_space *vm;
if (args->size)
return -EINVAL;
if (!HAS_FULL_PPGTT(i915))
return -ENODEV;
if (upper_32_bits(args->value))
return -ENOENT;
vm = i915_gem_vm_lookup(fpriv, args->value);
if (!vm)
return -ENOENT;
if (pc->vm)
i915_vm_put(pc->vm);
pc->vm = vm;
return 0;
}
struct set_proto_ctx_engines {
struct drm_i915_private *i915;
unsigned num_engines;
struct i915_gem_proto_engine *engines;
};
static int
set_proto_ctx_engines_balance(struct i915_user_extension __user *base,
void *data)
{
struct i915_context_engines_load_balance __user *ext =
container_of_user(base, typeof(*ext), base);
const struct set_proto_ctx_engines *set = data;
struct drm_i915_private *i915 = set->i915;
struct intel_engine_cs **siblings;
u16 num_siblings, idx;
unsigned int n;
int err;
if (!HAS_EXECLISTS(i915))
return -ENODEV;
if (get_user(idx, &ext->engine_index))
return -EFAULT;
if (idx >= set->num_engines) {
drm_dbg(&i915->drm, "Invalid placement value, %d >= %d\n",
idx, set->num_engines);
return -EINVAL;
}
idx = array_index_nospec(idx, set->num_engines);
if (set->engines[idx].type != I915_GEM_ENGINE_TYPE_INVALID) {
drm_dbg(&i915->drm,
"Invalid placement[%d], already occupied\n", idx);
return -EEXIST;
}
if (get_user(num_siblings, &ext->num_siblings))
return -EFAULT;
err = check_user_mbz(&ext->flags);
if (err)
return err;
err = check_user_mbz(&ext->mbz64);
if (err)
return err;
if (num_siblings == 0)
return 0;
siblings = kmalloc_array(num_siblings, sizeof(*siblings), GFP_KERNEL);
if (!siblings)
return -ENOMEM;
for (n = 0; n < num_siblings; n++) {
struct i915_engine_class_instance ci;
if (copy_from_user(&ci, &ext->engines[n], sizeof(ci))) {
err = -EFAULT;
goto err_siblings;
}
siblings[n] = intel_engine_lookup_user(i915,
ci.engine_class,
ci.engine_instance);
if (!siblings[n]) {
drm_dbg(&i915->drm,
"Invalid sibling[%d]: { class:%d, inst:%d }\n",
n, ci.engine_class, ci.engine_instance);
err = -EINVAL;
goto err_siblings;
}
}
if (num_siblings == 1) {
set->engines[idx].type = I915_GEM_ENGINE_TYPE_PHYSICAL;
set->engines[idx].engine = siblings[0];
kfree(siblings);
} else {
set->engines[idx].type = I915_GEM_ENGINE_TYPE_BALANCED;
set->engines[idx].num_siblings = num_siblings;
set->engines[idx].siblings = siblings;
}
return 0;
err_siblings:
kfree(siblings);
return err;
}
static int
set_proto_ctx_engines_bond(struct i915_user_extension __user *base, void *data)
{
struct i915_context_engines_bond __user *ext =
container_of_user(base, typeof(*ext), base);
const struct set_proto_ctx_engines *set = data;
struct drm_i915_private *i915 = set->i915;
struct i915_engine_class_instance ci;
struct intel_engine_cs *master;
u16 idx, num_bonds;
int err, n;
if (GRAPHICS_VER(i915) >= 12 && !IS_TIGERLAKE(i915) &&
!IS_ROCKETLAKE(i915) && !IS_ALDERLAKE_S(i915)) {
drm_dbg(&i915->drm,
"Bonding not supported on this platform\n");
return -ENODEV;
}
if (get_user(idx, &ext->virtual_index))
return -EFAULT;
if (idx >= set->num_engines) {
drm_dbg(&i915->drm,
"Invalid index for virtual engine: %d >= %d\n",
idx, set->num_engines);
return -EINVAL;
}
idx = array_index_nospec(idx, set->num_engines);
if (set->engines[idx].type == I915_GEM_ENGINE_TYPE_INVALID) {
drm_dbg(&i915->drm, "Invalid engine at %d\n", idx);
return -EINVAL;
}
if (set->engines[idx].type != I915_GEM_ENGINE_TYPE_PHYSICAL) {
drm_dbg(&i915->drm,
"Bonding with virtual engines not allowed\n");
return -EINVAL;
}
err = check_user_mbz(&ext->flags);
if (err)
return err;
for (n = 0; n < ARRAY_SIZE(ext->mbz64); n++) {
err = check_user_mbz(&ext->mbz64[n]);
if (err)
return err;
}
if (copy_from_user(&ci, &ext->master, sizeof(ci)))
return -EFAULT;
master = intel_engine_lookup_user(i915,
ci.engine_class,
ci.engine_instance);
if (!master) {
drm_dbg(&i915->drm,
"Unrecognised master engine: { class:%u, instance:%u }\n",
ci.engine_class, ci.engine_instance);
return -EINVAL;
}
if (intel_engine_uses_guc(master)) {
DRM_DEBUG("bonding extension not supported with GuC submission");
return -ENODEV;
}
if (get_user(num_bonds, &ext->num_bonds))
return -EFAULT;
for (n = 0; n < num_bonds; n++) {
struct intel_engine_cs *bond;
if (copy_from_user(&ci, &ext->engines[n], sizeof(ci)))
return -EFAULT;
bond = intel_engine_lookup_user(i915,
ci.engine_class,
ci.engine_instance);
if (!bond) {
drm_dbg(&i915->drm,
"Unrecognised engine[%d] for bonding: { class:%d, instance: %d }\n",
n, ci.engine_class, ci.engine_instance);
return -EINVAL;
}
}
return 0;
}
static int
set_proto_ctx_engines_parallel_submit(struct i915_user_extension __user *base,
void *data)
{
struct i915_context_engines_parallel_submit __user *ext =
container_of_user(base, typeof(*ext), base);
const struct set_proto_ctx_engines *set = data;
struct drm_i915_private *i915 = set->i915;
struct i915_engine_class_instance prev_engine;
u64 flags;
int err = 0, n, i, j;
u16 slot, width, num_siblings;
struct intel_engine_cs **siblings = NULL;
intel_engine_mask_t prev_mask;
if (get_user(slot, &ext->engine_index))
return -EFAULT;
if (get_user(width, &ext->width))
return -EFAULT;
if (get_user(num_siblings, &ext->num_siblings))
return -EFAULT;
if (!intel_uc_uses_guc_submission(&to_gt(i915)->uc) &&
num_siblings != 1) {
drm_dbg(&i915->drm, "Only 1 sibling (%d) supported in non-GuC mode\n",
num_siblings);
return -EINVAL;
}
if (slot >= set->num_engines) {
drm_dbg(&i915->drm, "Invalid placement value, %d >= %d\n",
slot, set->num_engines);
return -EINVAL;
}
if (set->engines[slot].type != I915_GEM_ENGINE_TYPE_INVALID) {
drm_dbg(&i915->drm,
"Invalid placement[%d], already occupied\n", slot);
return -EINVAL;
}
if (get_user(flags, &ext->flags))
return -EFAULT;
if (flags) {
drm_dbg(&i915->drm, "Unknown flags 0x%02llx", flags);
return -EINVAL;
}
for (n = 0; n < ARRAY_SIZE(ext->mbz64); n++) {
err = check_user_mbz(&ext->mbz64[n]);
if (err)
return err;
}
if (width < 2) {
drm_dbg(&i915->drm, "Width (%d) < 2\n", width);
return -EINVAL;
}
if (num_siblings < 1) {
drm_dbg(&i915->drm, "Number siblings (%d) < 1\n",
num_siblings);
return -EINVAL;
}
siblings = kmalloc_array(num_siblings * width,
sizeof(*siblings),
GFP_KERNEL);
if (!siblings)
return -ENOMEM;
/* Create contexts / engines */
for (i = 0; i < width; ++i) {
intel_engine_mask_t current_mask = 0;
for (j = 0; j < num_siblings; ++j) {
struct i915_engine_class_instance ci;
n = i * num_siblings + j;
if (copy_from_user(&ci, &ext->engines[n], sizeof(ci))) {
err = -EFAULT;
goto out_err;
}
siblings[n] =
intel_engine_lookup_user(i915, ci.engine_class,
ci.engine_instance);
if (!siblings[n]) {
drm_dbg(&i915->drm,
"Invalid sibling[%d]: { class:%d, inst:%d }\n",
n, ci.engine_class, ci.engine_instance);
err = -EINVAL;
goto out_err;
}
/*
* We don't support breadcrumb handshake on these
* classes
*/
if (siblings[n]->class == RENDER_CLASS ||
siblings[n]->class == COMPUTE_CLASS) {
err = -EINVAL;
goto out_err;
}
if (n) {
if (prev_engine.engine_class !=
ci.engine_class) {
drm_dbg(&i915->drm,
"Mismatched class %d, %d\n",
prev_engine.engine_class,
ci.engine_class);
err = -EINVAL;
goto out_err;
}
}
prev_engine = ci;
current_mask |= siblings[n]->logical_mask;
}
if (i > 0) {
if (current_mask != prev_mask << 1) {
drm_dbg(&i915->drm,
"Non contiguous logical mask 0x%x, 0x%x\n",
prev_mask, current_mask);
err = -EINVAL;
goto out_err;
}
}
prev_mask = current_mask;
}
set->engines[slot].type = I915_GEM_ENGINE_TYPE_PARALLEL;
set->engines[slot].num_siblings = num_siblings;
set->engines[slot].width = width;
set->engines[slot].siblings = siblings;
return 0;
out_err:
kfree(siblings);
return err;
}
static const i915_user_extension_fn set_proto_ctx_engines_extensions[] = {
[I915_CONTEXT_ENGINES_EXT_LOAD_BALANCE] = set_proto_ctx_engines_balance,
[I915_CONTEXT_ENGINES_EXT_BOND] = set_proto_ctx_engines_bond,
[I915_CONTEXT_ENGINES_EXT_PARALLEL_SUBMIT] =
set_proto_ctx_engines_parallel_submit,
};
static int set_proto_ctx_engines(struct drm_i915_file_private *fpriv,
struct i915_gem_proto_context *pc,
const struct drm_i915_gem_context_param *args)
{
struct drm_i915_private *i915 = fpriv->dev_priv;
struct set_proto_ctx_engines set = { .i915 = i915 };
struct i915_context_param_engines __user *user =
u64_to_user_ptr(args->value);
unsigned int n;
u64 extensions;
int err;
if (pc->num_user_engines >= 0) {
drm_dbg(&i915->drm, "Cannot set engines twice");
return -EINVAL;
}
if (args->size < sizeof(*user) ||
!IS_ALIGNED(args->size - sizeof(*user), sizeof(*user->engines))) {
drm_dbg(&i915->drm, "Invalid size for engine array: %d\n",
args->size);
return -EINVAL;
}
set.num_engines = (args->size - sizeof(*user)) / sizeof(*user->engines);
/* RING_MASK has no shift so we can use it directly here */
if (set.num_engines > I915_EXEC_RING_MASK + 1)
return -EINVAL;
set.engines = kmalloc_array(set.num_engines, sizeof(*set.engines), GFP_KERNEL);
if (!set.engines)
return -ENOMEM;
for (n = 0; n < set.num_engines; n++) {
struct i915_engine_class_instance ci;
struct intel_engine_cs *engine;
if (copy_from_user(&ci, &user->engines[n], sizeof(ci))) {
kfree(set.engines);
return -EFAULT;
}
memset(&set.engines[n], 0, sizeof(set.engines[n]));
if (ci.engine_class == (u16)I915_ENGINE_CLASS_INVALID &&
ci.engine_instance == (u16)I915_ENGINE_CLASS_INVALID_NONE)
continue;
engine = intel_engine_lookup_user(i915,
ci.engine_class,
ci.engine_instance);
if (!engine) {
drm_dbg(&i915->drm,
"Invalid engine[%d]: { class:%d, instance:%d }\n",
n, ci.engine_class, ci.engine_instance);
kfree(set.engines);
return -ENOENT;
}
set.engines[n].type = I915_GEM_ENGINE_TYPE_PHYSICAL;
set.engines[n].engine = engine;
}
err = -EFAULT;
if (!get_user(extensions, &user->extensions))
err = i915_user_extensions(u64_to_user_ptr(extensions),
set_proto_ctx_engines_extensions,
ARRAY_SIZE(set_proto_ctx_engines_extensions),
&set);
if (err) {
kfree(set.engines);
return err;
}
pc->num_user_engines = set.num_engines;
pc->user_engines = set.engines;
return 0;
}
static int set_proto_ctx_sseu(struct drm_i915_file_private *fpriv,
struct i915_gem_proto_context *pc,
struct drm_i915_gem_context_param *args)
{
struct drm_i915_private *i915 = fpriv->dev_priv;
struct drm_i915_gem_context_param_sseu user_sseu;
struct intel_sseu *sseu;
int ret;
if (args->size < sizeof(user_sseu))
return -EINVAL;
if (GRAPHICS_VER(i915) != 11)
return -ENODEV;
if (copy_from_user(&user_sseu, u64_to_user_ptr(args->value),
sizeof(user_sseu)))
return -EFAULT;
if (user_sseu.rsvd)
return -EINVAL;
if (user_sseu.flags & ~(I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX))
return -EINVAL;
if (!!(user_sseu.flags & I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX) != (pc->num_user_engines >= 0))
return -EINVAL;
if (pc->num_user_engines >= 0) {
int idx = user_sseu.engine.engine_instance;
struct i915_gem_proto_engine *pe;
if (idx >= pc->num_user_engines)
return -EINVAL;
pe = &pc->user_engines[idx];
/* Only render engine supports RPCS configuration. */
if (pe->engine->class != RENDER_CLASS)
return -EINVAL;
sseu = &pe->sseu;
} else {
/* Only render engine supports RPCS configuration. */
if (user_sseu.engine.engine_class != I915_ENGINE_CLASS_RENDER)
return -EINVAL;
/* There is only one render engine */
if (user_sseu.engine.engine_instance != 0)
return -EINVAL;
sseu = &pc->legacy_rcs_sseu;
}
ret = i915_gem_user_to_context_sseu(to_gt(i915), &user_sseu, sseu);
if (ret)
return ret;
args->size = sizeof(user_sseu);
return 0;
}
static int set_proto_ctx_param(struct drm_i915_file_private *fpriv,
struct i915_gem_proto_context *pc,
struct drm_i915_gem_context_param *args)
{
int ret = 0;
switch (args->param) {
case I915_CONTEXT_PARAM_NO_ERROR_CAPTURE:
if (args->size)
ret = -EINVAL;
else if (args->value)
pc->user_flags |= BIT(UCONTEXT_NO_ERROR_CAPTURE);
else
pc->user_flags &= ~BIT(UCONTEXT_NO_ERROR_CAPTURE);
break;
case I915_CONTEXT_PARAM_BANNABLE:
if (args->size)
ret = -EINVAL;
else if (!capable(CAP_SYS_ADMIN) && !args->value)
ret = -EPERM;
else if (args->value)
pc->user_flags |= BIT(UCONTEXT_BANNABLE);
else if (pc->uses_protected_content)
ret = -EPERM;
else
pc->user_flags &= ~BIT(UCONTEXT_BANNABLE);
break;
case I915_CONTEXT_PARAM_RECOVERABLE:
if (args->size)
ret = -EINVAL;
else if (!args->value)
pc->user_flags &= ~BIT(UCONTEXT_RECOVERABLE);
else if (pc->uses_protected_content)
ret = -EPERM;
else
pc->user_flags |= BIT(UCONTEXT_RECOVERABLE);
break;
case I915_CONTEXT_PARAM_PRIORITY:
ret = validate_priority(fpriv->dev_priv, args);
if (!ret)
pc->sched.priority = args->value;
break;
case I915_CONTEXT_PARAM_SSEU:
ret = set_proto_ctx_sseu(fpriv, pc, args);
break;
case I915_CONTEXT_PARAM_VM:
ret = set_proto_ctx_vm(fpriv, pc, args);
break;
case I915_CONTEXT_PARAM_ENGINES:
ret = set_proto_ctx_engines(fpriv, pc, args);
break;
case I915_CONTEXT_PARAM_PERSISTENCE:
if (args->size)
ret = -EINVAL;
else
ret = proto_context_set_persistence(fpriv->dev_priv, pc,
args->value);
break;
case I915_CONTEXT_PARAM_PROTECTED_CONTENT:
ret = proto_context_set_protected(fpriv->dev_priv, pc,
args->value);
break;
case I915_CONTEXT_PARAM_NO_ZEROMAP:
case I915_CONTEXT_PARAM_BAN_PERIOD:
case I915_CONTEXT_PARAM_RINGSIZE:
default:
ret = -EINVAL;
break;
}
return ret;
}
static int intel_context_set_gem(struct intel_context *ce,
struct i915_gem_context *ctx,
struct intel_sseu sseu)
{
int ret = 0;
GEM_BUG_ON(rcu_access_pointer(ce->gem_context));
RCU_INIT_POINTER(ce->gem_context, ctx);
GEM_BUG_ON(intel_context_is_pinned(ce));
ce->ring_size = SZ_16K;
i915_vm_put(ce->vm);
ce->vm = i915_gem_context_get_eb_vm(ctx);
if (ctx->sched.priority >= I915_PRIORITY_NORMAL &&
intel_engine_has_timeslices(ce->engine) &&
intel_engine_has_semaphores(ce->engine))
__set_bit(CONTEXT_USE_SEMAPHORES, &ce->flags);
if (CONFIG_DRM_I915_REQUEST_TIMEOUT &&
ctx->i915->params.request_timeout_ms) {
unsigned int timeout_ms = ctx->i915->params.request_timeout_ms;
intel_context_set_watchdog_us(ce, (u64)timeout_ms * 1000);
}
/* A valid SSEU has no zero fields */
if (sseu.slice_mask && !WARN_ON(ce->engine->class != RENDER_CLASS))
ret = intel_context_reconfigure_sseu(ce, sseu);
return ret;
}
static void __unpin_engines(struct i915_gem_engines *e, unsigned int count)
{
while (count--) {
struct intel_context *ce = e->engines[count], *child;
if (!ce || !test_bit(CONTEXT_PERMA_PIN, &ce->flags))
continue;
for_each_child(ce, child)
intel_context_unpin(child);
intel_context_unpin(ce);
}
}
static void unpin_engines(struct i915_gem_engines *e)
{
__unpin_engines(e, e->num_engines);
}
static void __free_engines(struct i915_gem_engines *e, unsigned int count)
{
while (count--) {
if (!e->engines[count])
continue;
intel_context_put(e->engines[count]);
}
kfree(e);
}
static void free_engines(struct i915_gem_engines *e)
{
__free_engines(e, e->num_engines);
}
static void free_engines_rcu(struct rcu_head *rcu)
{
struct i915_gem_engines *engines =
container_of(rcu, struct i915_gem_engines, rcu);
i915_sw_fence_fini(&engines->fence);
free_engines(engines);
}
static void accumulate_runtime(struct i915_drm_client *client,
struct i915_gem_engines *engines)
{
struct i915_gem_engines_iter it;
struct intel_context *ce;
if (!client)
return;
/* Transfer accumulated runtime to the parent GEM context. */
for_each_gem_engine(ce, engines, it) {
unsigned int class = ce->engine->uabi_class;
GEM_BUG_ON(class >= ARRAY_SIZE(client->past_runtime));
atomic64_add(intel_context_get_total_runtime_ns(ce),
&client->past_runtime[class]);
}
}
static int
engines_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
{
struct i915_gem_engines *engines =
container_of(fence, typeof(*engines), fence);
struct i915_gem_context *ctx = engines->ctx;
switch (state) {
case FENCE_COMPLETE:
if (!list_empty(&engines->link)) {
unsigned long flags;
spin_lock_irqsave(&ctx->stale.lock, flags);
list_del(&engines->link);
spin_unlock_irqrestore(&ctx->stale.lock, flags);
}
accumulate_runtime(ctx->client, engines);
i915_gem_context_put(ctx);
break;
case FENCE_FREE:
init_rcu_head(&engines->rcu);
call_rcu(&engines->rcu, free_engines_rcu);
break;
}
return NOTIFY_DONE;
}
static struct i915_gem_engines *alloc_engines(unsigned int count)
{
struct i915_gem_engines *e;
e = kzalloc(struct_size(e, engines, count), GFP_KERNEL);
if (!e)
return NULL;
i915_sw_fence_init(&e->fence, engines_notify);
return e;
}
static struct i915_gem_engines *default_engines(struct i915_gem_context *ctx,
struct intel_sseu rcs_sseu)
{
const struct intel_gt *gt = to_gt(ctx->i915);
struct intel_engine_cs *engine;
struct i915_gem_engines *e, *err;
enum intel_engine_id id;
e = alloc_engines(I915_NUM_ENGINES);
if (!e)
return ERR_PTR(-ENOMEM);
for_each_engine(engine, gt, id) {
struct intel_context *ce;
struct intel_sseu sseu = {};
int ret;
if (engine->legacy_idx == INVALID_ENGINE)
continue;
GEM_BUG_ON(engine->legacy_idx >= I915_NUM_ENGINES);
GEM_BUG_ON(e->engines[engine->legacy_idx]);
ce = intel_context_create(engine);
if (IS_ERR(ce)) {
err = ERR_CAST(ce);
goto free_engines;
}
e->engines[engine->legacy_idx] = ce;
e->num_engines = max(e->num_engines, engine->legacy_idx + 1);
if (engine->class == RENDER_CLASS)
sseu = rcs_sseu;
ret = intel_context_set_gem(ce, ctx, sseu);
if (ret) {
err = ERR_PTR(ret);
goto free_engines;
}
}
return e;
free_engines:
free_engines(e);
return err;
}
static int perma_pin_contexts(struct intel_context *ce)
{
struct intel_context *child;
int i = 0, j = 0, ret;
GEM_BUG_ON(!intel_context_is_parent(ce));
ret = intel_context_pin(ce);
if (unlikely(ret))
return ret;
for_each_child(ce, child) {
ret = intel_context_pin(child);
if (unlikely(ret))
goto unwind;
++i;
}
set_bit(CONTEXT_PERMA_PIN, &ce->flags);
return 0;
unwind:
intel_context_unpin(ce);
for_each_child(ce, child) {
if (j++ < i)
intel_context_unpin(child);
else
break;
}
return ret;
}
static struct i915_gem_engines *user_engines(struct i915_gem_context *ctx,
unsigned int num_engines,
struct i915_gem_proto_engine *pe)
{
struct i915_gem_engines *e, *err;
unsigned int n;
e = alloc_engines(num_engines);
if (!e)
return ERR_PTR(-ENOMEM);
e->num_engines = num_engines;
for (n = 0; n < num_engines; n++) {
struct intel_context *ce, *child;
int ret;
switch (pe[n].type) {
case I915_GEM_ENGINE_TYPE_PHYSICAL:
ce = intel_context_create(pe[n].engine);
break;
case I915_GEM_ENGINE_TYPE_BALANCED:
ce = intel_engine_create_virtual(pe[n].siblings,
pe[n].num_siblings, 0);
break;
case I915_GEM_ENGINE_TYPE_PARALLEL:
ce = intel_engine_create_parallel(pe[n].siblings,
pe[n].num_siblings,
pe[n].width);
break;
case I915_GEM_ENGINE_TYPE_INVALID:
default:
GEM_WARN_ON(pe[n].type != I915_GEM_ENGINE_TYPE_INVALID);
continue;
}
if (IS_ERR(ce)) {
err = ERR_CAST(ce);
goto free_engines;
}
e->engines[n] = ce;
ret = intel_context_set_gem(ce, ctx, pe->sseu);
if (ret) {
err = ERR_PTR(ret);
goto free_engines;
}
for_each_child(ce, child) {
ret = intel_context_set_gem(child, ctx, pe->sseu);
if (ret) {
err = ERR_PTR(ret);
goto free_engines;
}
}
/*
* XXX: Must be done after calling intel_context_set_gem as that
* function changes the ring size. The ring is allocated when
* the context is pinned. If the ring size is changed after
* allocation we have a mismatch of the ring size and will cause
* the context to hang. Presumably with a bit of reordering we
* could move the perma-pin step to the backend function
* intel_engine_create_parallel.
*/
if (pe[n].type == I915_GEM_ENGINE_TYPE_PARALLEL) {
ret = perma_pin_contexts(ce);
if (ret) {
err = ERR_PTR(ret);
goto free_engines;
}
}
}
return e;
free_engines:
free_engines(e);
return err;
}
static void i915_gem_context_release_work(struct work_struct *work)
{
struct i915_gem_context *ctx = container_of(work, typeof(*ctx),
release_work);
struct i915_address_space *vm;
trace_i915_context_free(ctx);
GEM_BUG_ON(!i915_gem_context_is_closed(ctx));
spin_lock(&ctx->i915->gem.contexts.lock);
list_del(&ctx->link);
spin_unlock(&ctx->i915->gem.contexts.lock);
if (ctx->syncobj)
drm_syncobj_put(ctx->syncobj);
vm = ctx->vm;
if (vm)
i915_vm_put(vm);
if (ctx->pxp_wakeref)
intel_runtime_pm_put(&ctx->i915->runtime_pm, ctx->pxp_wakeref);
if (ctx->client)
i915_drm_client_put(ctx->client);
mutex_destroy(&ctx->engines_mutex);
mutex_destroy(&ctx->lut_mutex);
put_pid(ctx->pid);
mutex_destroy(&ctx->mutex);
kfree_rcu(ctx, rcu);
}
void i915_gem_context_release(struct kref *ref)
{
struct i915_gem_context *ctx = container_of(ref, typeof(*ctx), ref);
queue_work(ctx->i915->wq, &ctx->release_work);
}
static inline struct i915_gem_engines *
__context_engines_static(const struct i915_gem_context *ctx)
{
return rcu_dereference_protected(ctx->engines, true);
}
static void __reset_context(struct i915_gem_context *ctx,
struct intel_engine_cs *engine)
{
intel_gt_handle_error(engine->gt, engine->mask, 0,
"context closure in %s", ctx->name);
}
static bool __cancel_engine(struct intel_engine_cs *engine)
{
/*
* Send a "high priority pulse" down the engine to cause the
* current request to be momentarily preempted. (If it fails to
* be preempted, it will be reset). As we have marked our context
* as banned, any incomplete request, including any running, will
* be skipped following the preemption.
*
* If there is no hangchecking (one of the reasons why we try to
* cancel the context) and no forced preemption, there may be no
* means by which we reset the GPU and evict the persistent hog.
* Ergo if we are unable to inject a preemptive pulse that can
* kill the banned context, we fallback to doing a local reset
* instead.
*/
return intel_engine_pulse(engine) == 0;
}
static struct intel_engine_cs *active_engine(struct intel_context *ce)
{
struct intel_engine_cs *engine = NULL;
struct i915_request *rq;
if (intel_context_has_inflight(ce))
return intel_context_inflight(ce);
if (!ce->timeline)
return NULL;
/*
* rq->link is only SLAB_TYPESAFE_BY_RCU, we need to hold a reference
* to the request to prevent it being transferred to a new timeline
* (and onto a new timeline->requests list).
*/
rcu_read_lock();
list_for_each_entry_reverse(rq, &ce->timeline->requests, link) {
bool found;
/* timeline is already completed upto this point? */
if (!i915_request_get_rcu(rq))
break;
/* Check with the backend if the request is inflight */
found = true;
if (likely(rcu_access_pointer(rq->timeline) == ce->timeline))
found = i915_request_active_engine(rq, &engine);
i915_request_put(rq);
if (found)
break;
}
rcu_read_unlock();
return engine;
}
static void
kill_engines(struct i915_gem_engines *engines, bool exit, bool persistent)
{
struct i915_gem_engines_iter it;
struct intel_context *ce;
/*
* Map the user's engine back to the actual engines; one virtual
* engine will be mapped to multiple engines, and using ctx->engine[]
* the same engine may be have multiple instances in the user's map.
* However, we only care about pending requests, so only include
* engines on which there are incomplete requests.
*/
for_each_gem_engine(ce, engines, it) {
struct intel_engine_cs *engine;
if ((exit || !persistent) && intel_context_revoke(ce))
continue; /* Already marked. */
/*
* Check the current active state of this context; if we
* are currently executing on the GPU we need to evict
* ourselves. On the other hand, if we haven't yet been
* submitted to the GPU or if everything is complete,
* we have nothing to do.
*/
engine = active_engine(ce);
/* First attempt to gracefully cancel the context */
if (engine && !__cancel_engine(engine) && (exit || !persistent))
/*
* If we are unable to send a preemptive pulse to bump
* the context from the GPU, we have to resort to a full
* reset. We hope the collateral damage is worth it.
*/
__reset_context(engines->ctx, engine);
}
}
static void kill_context(struct i915_gem_context *ctx)
{
struct i915_gem_engines *pos, *next;
spin_lock_irq(&ctx->stale.lock);
GEM_BUG_ON(!i915_gem_context_is_closed(ctx));
list_for_each_entry_safe(pos, next, &ctx->stale.engines, link) {
if (!i915_sw_fence_await(&pos->fence)) {
list_del_init(&pos->link);
continue;
}
spin_unlock_irq(&ctx->stale.lock);
kill_engines(pos, !ctx->i915->params.enable_hangcheck,
i915_gem_context_is_persistent(ctx));
spin_lock_irq(&ctx->stale.lock);
GEM_BUG_ON(i915_sw_fence_signaled(&pos->fence));
list_safe_reset_next(pos, next, link);
list_del_init(&pos->link); /* decouple from FENCE_COMPLETE */
i915_sw_fence_complete(&pos->fence);
}
spin_unlock_irq(&ctx->stale.lock);
}
static void engines_idle_release(struct i915_gem_context *ctx,
struct i915_gem_engines *engines)
{
struct i915_gem_engines_iter it;
struct intel_context *ce;
INIT_LIST_HEAD(&engines->link);
engines->ctx = i915_gem_context_get(ctx);
for_each_gem_engine(ce, engines, it) {
int err;
/* serialises with execbuf */
set_bit(CONTEXT_CLOSED_BIT, &ce->flags);
if (!intel_context_pin_if_active(ce))
continue;
/* Wait until context is finally scheduled out and retired */
err = i915_sw_fence_await_active(&engines->fence,
&ce->active,
I915_ACTIVE_AWAIT_BARRIER);
intel_context_unpin(ce);
if (err)
goto kill;
}
spin_lock_irq(&ctx->stale.lock);
if (!i915_gem_context_is_closed(ctx))
list_add_tail(&engines->link, &ctx->stale.engines);
spin_unlock_irq(&ctx->stale.lock);
kill:
if (list_empty(&engines->link)) /* raced, already closed */
kill_engines(engines, true,
i915_gem_context_is_persistent(ctx));
i915_sw_fence_commit(&engines->fence);
}
static void set_closed_name(struct i915_gem_context *ctx)
{
char *s;
/* Replace '[]' with '<>' to indicate closed in debug prints */
s = strrchr(ctx->name, '[');
if (!s)
return;
*s = '<';
s = strchr(s + 1, ']');
if (s)
*s = '>';
}
static void context_close(struct i915_gem_context *ctx)
{
struct i915_drm_client *client;
/* Flush any concurrent set_engines() */
mutex_lock(&ctx->engines_mutex);
unpin_engines(__context_engines_static(ctx));
engines_idle_release(ctx, rcu_replace_pointer(ctx->engines, NULL, 1));
i915_gem_context_set_closed(ctx);
mutex_unlock(&ctx->engines_mutex);
mutex_lock(&ctx->mutex);
set_closed_name(ctx);
/*
* The LUT uses the VMA as a backpointer to unref the object,
* so we need to clear the LUT before we close all the VMA (inside
* the ppgtt).
*/
lut_close(ctx);
ctx->file_priv = ERR_PTR(-EBADF);
client = ctx->client;
if (client) {
spin_lock(&client->ctx_lock);
list_del_rcu(&ctx->client_link);
spin_unlock(&client->ctx_lock);
}
mutex_unlock(&ctx->mutex);
/*
* If the user has disabled hangchecking, we can not be sure that
* the batches will ever complete after the context is closed,
* keeping the context and all resources pinned forever. So in this
* case we opt to forcibly kill off all remaining requests on
* context close.
*/
kill_context(ctx);
i915_gem_context_put(ctx);
}
static int __context_set_persistence(struct i915_gem_context *ctx, bool state)
{
if (i915_gem_context_is_persistent(ctx) == state)
return 0;
if (state) {
/*
* Only contexts that are short-lived [that will expire or be
* reset] are allowed to survive past termination. We require
* hangcheck to ensure that the persistent requests are healthy.
*/
if (!ctx->i915->params.enable_hangcheck)
return -EINVAL;
i915_gem_context_set_persistence(ctx);
} else {
/* To cancel a context we use "preempt-to-idle" */
if (!(ctx->i915->caps.scheduler & I915_SCHEDULER_CAP_PREEMPTION))
return -ENODEV;
/*
* If the cancel fails, we then need to reset, cleanly!
*
* If the per-engine reset fails, all hope is lost! We resort
* to a full GPU reset in that unlikely case, but realistically
* if the engine could not reset, the full reset does not fare
* much better. The damage has been done.
*
* However, if we cannot reset an engine by itself, we cannot
* cleanup a hanging persistent context without causing
* colateral damage, and we should not pretend we can by
* exposing the interface.
*/
if (!intel_has_reset_engine(to_gt(ctx->i915)))
return -ENODEV;
i915_gem_context_clear_persistence(ctx);
}
return 0;
}
static struct i915_gem_context *
i915_gem_create_context(struct drm_i915_private *i915,
const struct i915_gem_proto_context *pc)
{
struct i915_gem_context *ctx;
struct i915_address_space *vm = NULL;
struct i915_gem_engines *e;
int err;
int i;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return ERR_PTR(-ENOMEM);
kref_init(&ctx->ref);
ctx->i915 = i915;
ctx->sched = pc->sched;
mutex_init(&ctx->mutex);
INIT_LIST_HEAD(&ctx->link);
INIT_WORK(&ctx->release_work, i915_gem_context_release_work);
spin_lock_init(&ctx->stale.lock);
INIT_LIST_HEAD(&ctx->stale.engines);
if (pc->vm) {
vm = i915_vm_get(pc->vm);
} else if (HAS_FULL_PPGTT(i915)) {
struct i915_ppgtt *ppgtt;
ppgtt = i915_ppgtt_create(to_gt(i915), 0);
if (IS_ERR(ppgtt)) {
drm_dbg(&i915->drm, "PPGTT setup failed (%ld)\n",
PTR_ERR(ppgtt));
err = PTR_ERR(ppgtt);
goto err_ctx;
}
vm = &ppgtt->vm;
}
if (vm)
ctx->vm = vm;
mutex_init(&ctx->engines_mutex);
if (pc->num_user_engines >= 0) {
i915_gem_context_set_user_engines(ctx);
e = user_engines(ctx, pc->num_user_engines, pc->user_engines);
} else {
i915_gem_context_clear_user_engines(ctx);
e = default_engines(ctx, pc->legacy_rcs_sseu);
}
if (IS_ERR(e)) {
err = PTR_ERR(e);
goto err_vm;
}
RCU_INIT_POINTER(ctx->engines, e);
INIT_RADIX_TREE(&ctx->handles_vma, GFP_KERNEL);
mutex_init(&ctx->lut_mutex);
/* NB: Mark all slices as needing a remap so that when the context first
* loads it will restore whatever remap state already exists. If there
* is no remap info, it will be a NOP. */
ctx->remap_slice = ALL_L3_SLICES(i915);
ctx->user_flags = pc->user_flags;
for (i = 0; i < ARRAY_SIZE(ctx->hang_timestamp); i++)
ctx->hang_timestamp[i] = jiffies - CONTEXT_FAST_HANG_JIFFIES;
if (pc->single_timeline) {
err = drm_syncobj_create(&ctx->syncobj,
DRM_SYNCOBJ_CREATE_SIGNALED,
NULL);
if (err)
goto err_engines;
}
if (pc->uses_protected_content) {
ctx->pxp_wakeref = intel_runtime_pm_get(&i915->runtime_pm);
ctx->uses_protected_content = true;
}
trace_i915_context_create(ctx);
return ctx;
err_engines:
free_engines(e);
err_vm:
if (ctx->vm)
i915_vm_put(ctx->vm);
err_ctx:
kfree(ctx);
return ERR_PTR(err);
}
static void init_contexts(struct i915_gem_contexts *gc)
{
spin_lock_init(&gc->lock);
INIT_LIST_HEAD(&gc->list);
}
void i915_gem_init__contexts(struct drm_i915_private *i915)
{
init_contexts(&i915->gem.contexts);
}
/*
* Note that this implicitly consumes the ctx reference, by placing
* the ctx in the context_xa.
*/
static void gem_context_register(struct i915_gem_context *ctx,
struct drm_i915_file_private *fpriv,
u32 id)
{
struct drm_i915_private *i915 = ctx->i915;
void *old;
ctx->file_priv = fpriv;
ctx->pid = get_task_pid(current, PIDTYPE_PID);
ctx->client = i915_drm_client_get(fpriv->client);
snprintf(ctx->name, sizeof(ctx->name), "%s[%d]",
current->comm, pid_nr(ctx->pid));
spin_lock(&ctx->client->ctx_lock);
list_add_tail_rcu(&ctx->client_link, &ctx->client->ctx_list);
spin_unlock(&ctx->client->ctx_lock);
spin_lock(&i915->gem.contexts.lock);
list_add_tail(&ctx->link, &i915->gem.contexts.list);
spin_unlock(&i915->gem.contexts.lock);
/* And finally expose ourselves to userspace via the idr */
old = xa_store(&fpriv->context_xa, id, ctx, GFP_KERNEL);
WARN_ON(old);
}
int i915_gem_context_open(struct drm_i915_private *i915,
struct drm_file *file)
{
struct drm_i915_file_private *file_priv = file->driver_priv;
struct i915_gem_proto_context *pc;
struct i915_gem_context *ctx;
int err;
mutex_init(&file_priv->proto_context_lock);
xa_init_flags(&file_priv->proto_context_xa, XA_FLAGS_ALLOC);
/* 0 reserved for the default context */
xa_init_flags(&file_priv->context_xa, XA_FLAGS_ALLOC1);
/* 0 reserved for invalid/unassigned ppgtt */
xa_init_flags(&file_priv->vm_xa, XA_FLAGS_ALLOC1);
pc = proto_context_create(i915, 0);
if (IS_ERR(pc)) {
err = PTR_ERR(pc);
goto err;
}
ctx = i915_gem_create_context(i915, pc);
proto_context_close(i915, pc);
if (IS_ERR(ctx)) {
err = PTR_ERR(ctx);
goto err;
}
gem_context_register(ctx, file_priv, 0);
return 0;
err:
xa_destroy(&file_priv->vm_xa);
xa_destroy(&file_priv->context_xa);
xa_destroy(&file_priv->proto_context_xa);
mutex_destroy(&file_priv->proto_context_lock);
return err;
}
void i915_gem_context_close(struct drm_file *file)
{
struct drm_i915_file_private *file_priv = file->driver_priv;
struct i915_gem_proto_context *pc;
struct i915_address_space *vm;
struct i915_gem_context *ctx;
unsigned long idx;
xa_for_each(&file_priv->proto_context_xa, idx, pc)
proto_context_close(file_priv->dev_priv, pc);
xa_destroy(&file_priv->proto_context_xa);
mutex_destroy(&file_priv->proto_context_lock);
xa_for_each(&file_priv->context_xa, idx, ctx)
context_close(ctx);
xa_destroy(&file_priv->context_xa);
xa_for_each(&file_priv->vm_xa, idx, vm)
i915_vm_put(vm);
xa_destroy(&file_priv->vm_xa);
}
int i915_gem_vm_create_ioctl(struct drm_device *dev, void *data,
struct drm_file *file)
{
struct drm_i915_private *i915 = to_i915(dev);
struct drm_i915_gem_vm_control *args = data;
struct drm_i915_file_private *file_priv = file->driver_priv;
struct i915_ppgtt *ppgtt;
u32 id;
int err;
if (!HAS_FULL_PPGTT(i915))
return -ENODEV;
if (args->flags)
return -EINVAL;
ppgtt = i915_ppgtt_create(to_gt(i915), 0);
if (IS_ERR(ppgtt))
return PTR_ERR(ppgtt);
if (args->extensions) {
err = i915_user_extensions(u64_to_user_ptr(args->extensions),
NULL, 0,
ppgtt);
if (err)
goto err_put;
}
err = xa_alloc(&file_priv->vm_xa, &id, &ppgtt->vm,
xa_limit_32b, GFP_KERNEL);
if (err)
goto err_put;
GEM_BUG_ON(id == 0); /* reserved for invalid/unassigned ppgtt */
args->vm_id = id;
return 0;
err_put:
i915_vm_put(&ppgtt->vm);
return err;
}
int i915_gem_vm_destroy_ioctl(struct drm_device *dev, void *data,
struct drm_file *file)
{
struct drm_i915_file_private *file_priv = file->driver_priv;
struct drm_i915_gem_vm_control *args = data;
struct i915_address_space *vm;
if (args->flags)
return -EINVAL;
if (args->extensions)
return -EINVAL;
vm = xa_erase(&file_priv->vm_xa, args->vm_id);
if (!vm)
return -ENOENT;
i915_vm_put(vm);
return 0;
}
static int get_ppgtt(struct drm_i915_file_private *file_priv,
struct i915_gem_context *ctx,
struct drm_i915_gem_context_param *args)
{
struct i915_address_space *vm;
int err;
u32 id;
if (!i915_gem_context_has_full_ppgtt(ctx))
return -ENODEV;
vm = ctx->vm;
GEM_BUG_ON(!vm);
/*
* Get a reference for the allocated handle. Once the handle is
* visible in the vm_xa table, userspace could try to close it
* from under our feet, so we need to hold the extra reference
* first.
*/
i915_vm_get(vm);
err = xa_alloc(&file_priv->vm_xa, &id, vm, xa_limit_32b, GFP_KERNEL);
if (err) {
i915_vm_put(vm);
return err;
}
GEM_BUG_ON(id == 0); /* reserved for invalid/unassigned ppgtt */
args->value = id;
args->size = 0;
return err;
}
int
i915_gem_user_to_context_sseu(struct intel_gt *gt,
const struct drm_i915_gem_context_param_sseu *user,
struct intel_sseu *context)
{
const struct sseu_dev_info *device = &gt->info.sseu;
struct drm_i915_private *i915 = gt->i915;
unsigned int dev_subslice_mask = intel_sseu_get_hsw_subslices(device, 0);
/* No zeros in any field. */
if (!user->slice_mask || !user->subslice_mask ||
!user->min_eus_per_subslice || !user->max_eus_per_subslice)
return -EINVAL;
/* Max > min. */
if (user->max_eus_per_subslice < user->min_eus_per_subslice)
return -EINVAL;
/*
* Some future proofing on the types since the uAPI is wider than the
* current internal implementation.
*/
if (overflows_type(user->slice_mask, context->slice_mask) ||
overflows_type(user->subslice_mask, context->subslice_mask) ||
overflows_type(user->min_eus_per_subslice,
context->min_eus_per_subslice) ||
overflows_type(user->max_eus_per_subslice,
context->max_eus_per_subslice))
return -EINVAL;
/* Check validity against hardware. */
if (user->slice_mask & ~device->slice_mask)
return -EINVAL;
if (user->subslice_mask & ~dev_subslice_mask)
return -EINVAL;
if (user->max_eus_per_subslice > device->max_eus_per_subslice)
return -EINVAL;
context->slice_mask = user->slice_mask;
context->subslice_mask = user->subslice_mask;
context->min_eus_per_subslice = user->min_eus_per_subslice;
context->max_eus_per_subslice = user->max_eus_per_subslice;
/* Part specific restrictions. */
if (GRAPHICS_VER(i915) == 11) {
unsigned int hw_s = hweight8(device->slice_mask);
unsigned int hw_ss_per_s = hweight8(dev_subslice_mask);
unsigned int req_s = hweight8(context->slice_mask);
unsigned int req_ss = hweight8(context->subslice_mask);
/*
* Only full subslice enablement is possible if more than one
* slice is turned on.
*/
if (req_s > 1 && req_ss != hw_ss_per_s)
return -EINVAL;
/*
* If more than four (SScount bitfield limit) subslices are
* requested then the number has to be even.
*/
if (req_ss > 4 && (req_ss & 1))
return -EINVAL;
/*
* If only one slice is enabled and subslice count is below the
* device full enablement, it must be at most half of the all
* available subslices.
*/
if (req_s == 1 && req_ss < hw_ss_per_s &&
req_ss > (hw_ss_per_s / 2))
return -EINVAL;
/* ABI restriction - VME use case only. */
/* All slices or one slice only. */
if (req_s != 1 && req_s != hw_s)
return -EINVAL;
/*
* Half subslices or full enablement only when one slice is
* enabled.
*/
if (req_s == 1 &&
(req_ss != hw_ss_per_s && req_ss != (hw_ss_per_s / 2)))
return -EINVAL;
/* No EU configuration changes. */
if ((user->min_eus_per_subslice !=
device->max_eus_per_subslice) ||
(user->max_eus_per_subslice !=
device->max_eus_per_subslice))
return -EINVAL;
}
return 0;
}
static int set_sseu(struct i915_gem_context *ctx,
struct drm_i915_gem_context_param *args)
{
struct drm_i915_private *i915 = ctx->i915;
struct drm_i915_gem_context_param_sseu user_sseu;
struct intel_context *ce;
struct intel_sseu sseu;
unsigned long lookup;
int ret;
if (args->size < sizeof(user_sseu))
return -EINVAL;
if (GRAPHICS_VER(i915) != 11)
return -ENODEV;
if (copy_from_user(&user_sseu, u64_to_user_ptr(args->value),
sizeof(user_sseu)))
return -EFAULT;
if (user_sseu.rsvd)
return -EINVAL;
if (user_sseu.flags & ~(I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX))
return -EINVAL;
lookup = 0;
if (user_sseu.flags & I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX)
lookup |= LOOKUP_USER_INDEX;
ce = lookup_user_engine(ctx, lookup, &user_sseu.engine);
if (IS_ERR(ce))
return PTR_ERR(ce);
/* Only render engine supports RPCS configuration. */
if (ce->engine->class != RENDER_CLASS) {
ret = -ENODEV;
goto out_ce;
}
ret = i915_gem_user_to_context_sseu(ce->engine->gt, &user_sseu, &sseu);
if (ret)
goto out_ce;
ret = intel_context_reconfigure_sseu(ce, sseu);
if (ret)
goto out_ce;
args->size = sizeof(user_sseu);
out_ce:
intel_context_put(ce);
return ret;
}
static int
set_persistence(struct i915_gem_context *ctx,
const struct drm_i915_gem_context_param *args)
{
if (args->size)
return -EINVAL;
return __context_set_persistence(ctx, args->value);
}
static int set_priority(struct i915_gem_context *ctx,
const struct drm_i915_gem_context_param *args)
{
struct i915_gem_engines_iter it;
struct intel_context *ce;
int err;
err = validate_priority(ctx->i915, args);
if (err)
return err;
ctx->sched.priority = args->value;
for_each_gem_engine(ce, i915_gem_context_lock_engines(ctx), it) {
if (!intel_engine_has_timeslices(ce->engine))
continue;
if (ctx->sched.priority >= I915_PRIORITY_NORMAL &&
intel_engine_has_semaphores(ce->engine))
intel_context_set_use_semaphores(ce);
else
intel_context_clear_use_semaphores(ce);
}
i915_gem_context_unlock_engines(ctx);
return 0;
}
static int get_protected(struct i915_gem_context *ctx,
struct drm_i915_gem_context_param *args)
{
args->size = 0;
args->value = i915_gem_context_uses_protected_content(ctx);
return 0;
}
static int ctx_setparam(struct drm_i915_file_private *fpriv,
struct i915_gem_context *ctx,
struct drm_i915_gem_context_param *args)
{
int ret = 0;
switch (args->param) {
case I915_CONTEXT_PARAM_NO_ERROR_CAPTURE:
if (args->size)
ret = -EINVAL;
else if (args->value)
i915_gem_context_set_no_error_capture(ctx);
else
i915_gem_context_clear_no_error_capture(ctx);
break;
case I915_CONTEXT_PARAM_BANNABLE:
if (args->size)
ret = -EINVAL;
else if (!capable(CAP_SYS_ADMIN) && !args->value)
ret = -EPERM;
else if (args->value)
i915_gem_context_set_bannable(ctx);
else if (i915_gem_context_uses_protected_content(ctx))
ret = -EPERM; /* can't clear this for protected contexts */
else
i915_gem_context_clear_bannable(ctx);
break;
case I915_CONTEXT_PARAM_RECOVERABLE:
if (args->size)
ret = -EINVAL;
else if (!args->value)
i915_gem_context_clear_recoverable(ctx);
else if (i915_gem_context_uses_protected_content(ctx))
ret = -EPERM; /* can't set this for protected contexts */
else
i915_gem_context_set_recoverable(ctx);
break;
case I915_CONTEXT_PARAM_PRIORITY:
ret = set_priority(ctx, args);
break;
case I915_CONTEXT_PARAM_SSEU:
ret = set_sseu(ctx, args);
break;
case I915_CONTEXT_PARAM_PERSISTENCE:
ret = set_persistence(ctx, args);
break;
case I915_CONTEXT_PARAM_PROTECTED_CONTENT:
case I915_CONTEXT_PARAM_NO_ZEROMAP:
case I915_CONTEXT_PARAM_BAN_PERIOD:
case I915_CONTEXT_PARAM_RINGSIZE:
case I915_CONTEXT_PARAM_VM:
case I915_CONTEXT_PARAM_ENGINES:
default:
ret = -EINVAL;
break;
}
return ret;
}
struct create_ext {
struct i915_gem_proto_context *pc;
struct drm_i915_file_private *fpriv;
};
static int create_setparam(struct i915_user_extension __user *ext, void *data)
{
struct drm_i915_gem_context_create_ext_setparam local;
const struct create_ext *arg = data;
if (copy_from_user(&local, ext, sizeof(local)))
return -EFAULT;
if (local.param.ctx_id)
return -EINVAL;
return set_proto_ctx_param(arg->fpriv, arg->pc, &local.param);
}
static int invalid_ext(struct i915_user_extension __user *ext, void *data)
{
return -EINVAL;
}
static const i915_user_extension_fn create_extensions[] = {
[I915_CONTEXT_CREATE_EXT_SETPARAM] = create_setparam,
[I915_CONTEXT_CREATE_EXT_CLONE] = invalid_ext,
};
static bool client_is_banned(struct drm_i915_file_private *file_priv)
{
return atomic_read(&file_priv->ban_score) >= I915_CLIENT_SCORE_BANNED;
}
static inline struct i915_gem_context *
__context_lookup(struct drm_i915_file_private *file_priv, u32 id)
{
struct i915_gem_context *ctx;
rcu_read_lock();
ctx = xa_load(&file_priv->context_xa, id);
if (ctx && !kref_get_unless_zero(&ctx->ref))
ctx = NULL;
rcu_read_unlock();
return ctx;
}
static struct i915_gem_context *
finalize_create_context_locked(struct drm_i915_file_private *file_priv,
struct i915_gem_proto_context *pc, u32 id)
{
struct i915_gem_context *ctx;
void *old;
lockdep_assert_held(&file_priv->proto_context_lock);
ctx = i915_gem_create_context(file_priv->dev_priv, pc);
if (IS_ERR(ctx))
return ctx;
/*
* One for the xarray and one for the caller. We need to grab
* the reference *prior* to making the ctx visble to userspace
* in gem_context_register(), as at any point after that
* userspace can try to race us with another thread destroying
* the context under our feet.
*/
i915_gem_context_get(ctx);
gem_context_register(ctx, file_priv, id);
old = xa_erase(&file_priv->proto_context_xa, id);
GEM_BUG_ON(old != pc);
proto_context_close(file_priv->dev_priv, pc);
return ctx;
}
struct i915_gem_context *
i915_gem_context_lookup(struct drm_i915_file_private *file_priv, u32 id)
{
struct i915_gem_proto_context *pc;
struct i915_gem_context *ctx;
ctx = __context_lookup(file_priv, id);
if (ctx)
return ctx;
mutex_lock(&file_priv->proto_context_lock);
/* Try one more time under the lock */
ctx = __context_lookup(file_priv, id);
if (!ctx) {
pc = xa_load(&file_priv->proto_context_xa, id);
if (!pc)
ctx = ERR_PTR(-ENOENT);
else
ctx = finalize_create_context_locked(file_priv, pc, id);
}
mutex_unlock(&file_priv->proto_context_lock);
return ctx;
}
int i915_gem_context_create_ioctl(struct drm_device *dev, void *data,
struct drm_file *file)
{
struct drm_i915_private *i915 = to_i915(dev);
struct drm_i915_gem_context_create_ext *args = data;
struct create_ext ext_data;
int ret;
u32 id;
if (!DRIVER_CAPS(i915)->has_logical_contexts)
return -ENODEV;
if (args->flags & I915_CONTEXT_CREATE_FLAGS_UNKNOWN)
return -EINVAL;
ret = intel_gt_terminally_wedged(to_gt(i915));
if (ret)
return ret;
ext_data.fpriv = file->driver_priv;
if (client_is_banned(ext_data.fpriv)) {
drm_dbg(&i915->drm,
"client %s[%d] banned from creating ctx\n",
current->comm, task_pid_nr(current));
return -EIO;
}
ext_data.pc = proto_context_create(i915, args->flags);
if (IS_ERR(ext_data.pc))
return PTR_ERR(ext_data.pc);
if (args->flags & I915_CONTEXT_CREATE_FLAGS_USE_EXTENSIONS) {
ret = i915_user_extensions(u64_to_user_ptr(args->extensions),
create_extensions,
ARRAY_SIZE(create_extensions),
&ext_data);
if (ret)
goto err_pc;
}
if (GRAPHICS_VER(i915) > 12) {
struct i915_gem_context *ctx;
/* Get ourselves a context ID */
ret = xa_alloc(&ext_data.fpriv->context_xa, &id, NULL,
xa_limit_32b, GFP_KERNEL);
if (ret)
goto err_pc;
ctx = i915_gem_create_context(i915, ext_data.pc);
if (IS_ERR(ctx)) {
ret = PTR_ERR(ctx);
goto err_pc;
}
proto_context_close(i915, ext_data.pc);
gem_context_register(ctx, ext_data.fpriv, id);
} else {
ret = proto_context_register(ext_data.fpriv, ext_data.pc, &id);
if (ret < 0)
goto err_pc;
}
args->ctx_id = id;
drm_dbg(&i915->drm, "HW context %d created\n", args->ctx_id);
return 0;
err_pc:
proto_context_close(i915, ext_data.pc);
return ret;
}
int i915_gem_context_destroy_ioctl(struct drm_device *dev, void *data,
struct drm_file *file)
{
struct drm_i915_gem_context_destroy *args = data;
struct drm_i915_file_private *file_priv = file->driver_priv;
struct i915_gem_proto_context *pc;
struct i915_gem_context *ctx;
if (args->pad != 0)
return -EINVAL;
if (!args->ctx_id)
return -ENOENT;
/* We need to hold the proto-context lock here to prevent races
* with finalize_create_context_locked().
*/
mutex_lock(&file_priv->proto_context_lock);
ctx = xa_erase(&file_priv->context_xa, args->ctx_id);
pc = xa_erase(&file_priv->proto_context_xa, args->ctx_id);
mutex_unlock(&file_priv->proto_context_lock);
if (!ctx && !pc)
return -ENOENT;
GEM_WARN_ON(ctx && pc);
if (pc)
proto_context_close(file_priv->dev_priv, pc);
if (ctx)
context_close(ctx);
return 0;
}
static int get_sseu(struct i915_gem_context *ctx,
struct drm_i915_gem_context_param *args)
{
struct drm_i915_gem_context_param_sseu user_sseu;
struct intel_context *ce;
unsigned long lookup;
int err;
if (args->size == 0)
goto out;
else if (args->size < sizeof(user_sseu))
return -EINVAL;
if (copy_from_user(&user_sseu, u64_to_user_ptr(args->value),
sizeof(user_sseu)))
return -EFAULT;
if (user_sseu.rsvd)
return -EINVAL;
if (user_sseu.flags & ~(I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX))
return -EINVAL;
lookup = 0;
if (user_sseu.flags & I915_CONTEXT_SSEU_FLAG_ENGINE_INDEX)
lookup |= LOOKUP_USER_INDEX;
ce = lookup_user_engine(ctx, lookup, &user_sseu.engine);
if (IS_ERR(ce))
return PTR_ERR(ce);
err = intel_context_lock_pinned(ce); /* serialises with set_sseu */
if (err) {
intel_context_put(ce);
return err;
}
user_sseu.slice_mask = ce->sseu.slice_mask;
user_sseu.subslice_mask = ce->sseu.subslice_mask;
user_sseu.min_eus_per_subslice = ce->sseu.min_eus_per_subslice;
user_sseu.max_eus_per_subslice = ce->sseu.max_eus_per_subslice;
intel_context_unlock_pinned(ce);
intel_context_put(ce);
if (copy_to_user(u64_to_user_ptr(args->value), &user_sseu,
sizeof(user_sseu)))
return -EFAULT;
out:
args->size = sizeof(user_sseu);
return 0;
}
int i915_gem_context_getparam_ioctl(struct drm_device *dev, void *data,
struct drm_file *file)
{
struct drm_i915_file_private *file_priv = file->driver_priv;
struct drm_i915_gem_context_param *args = data;
struct i915_gem_context *ctx;
struct i915_address_space *vm;
int ret = 0;
ctx = i915_gem_context_lookup(file_priv, args->ctx_id);
if (IS_ERR(ctx))
return PTR_ERR(ctx);
switch (args->param) {
case I915_CONTEXT_PARAM_GTT_SIZE:
args->size = 0;
vm = i915_gem_context_get_eb_vm(ctx);
args->value = vm->total;
i915_vm_put(vm);
break;
case I915_CONTEXT_PARAM_NO_ERROR_CAPTURE:
args->size = 0;
args->value = i915_gem_context_no_error_capture(ctx);
break;
case I915_CONTEXT_PARAM_BANNABLE:
args->size = 0;
args->value = i915_gem_context_is_bannable(ctx);
break;
case I915_CONTEXT_PARAM_RECOVERABLE:
args->size = 0;
args->value = i915_gem_context_is_recoverable(ctx);
break;
case I915_CONTEXT_PARAM_PRIORITY:
args->size = 0;
args->value = ctx->sched.priority;
break;
case I915_CONTEXT_PARAM_SSEU:
ret = get_sseu(ctx, args);
break;
case I915_CONTEXT_PARAM_VM:
ret = get_ppgtt(file_priv, ctx, args);
break;
case I915_CONTEXT_PARAM_PERSISTENCE:
args->size = 0;
args->value = i915_gem_context_is_persistent(ctx);
break;
case I915_CONTEXT_PARAM_PROTECTED_CONTENT:
ret = get_protected(ctx, args);
break;
case I915_CONTEXT_PARAM_NO_ZEROMAP:
case I915_CONTEXT_PARAM_BAN_PERIOD:
case I915_CONTEXT_PARAM_ENGINES:
case I915_CONTEXT_PARAM_RINGSIZE:
default:
ret = -EINVAL;
break;
}
i915_gem_context_put(ctx);
return ret;
}
int i915_gem_context_setparam_ioctl(struct drm_device *dev, void *data,
struct drm_file *file)
{
struct drm_i915_file_private *file_priv = file->driver_priv;
struct drm_i915_gem_context_param *args = data;
struct i915_gem_proto_context *pc;
struct i915_gem_context *ctx;
int ret = 0;
mutex_lock(&file_priv->proto_context_lock);
ctx = __context_lookup(file_priv, args->ctx_id);
if (!ctx) {
pc = xa_load(&file_priv->proto_context_xa, args->ctx_id);
if (pc) {
/* Contexts should be finalized inside
* GEM_CONTEXT_CREATE starting with graphics
* version 13.
*/
WARN_ON(GRAPHICS_VER(file_priv->dev_priv) > 12);
ret = set_proto_ctx_param(file_priv, pc, args);
} else {
ret = -ENOENT;
}
}
mutex_unlock(&file_priv->proto_context_lock);
if (ctx) {
ret = ctx_setparam(file_priv, ctx, args);
i915_gem_context_put(ctx);
}
return ret;
}
int i915_gem_context_reset_stats_ioctl(struct drm_device *dev,
void *data, struct drm_file *file)
{
struct drm_i915_private *i915 = to_i915(dev);
struct drm_i915_reset_stats *args = data;
struct i915_gem_context *ctx;
if (args->flags || args->pad)
return -EINVAL;
ctx = i915_gem_context_lookup(file->driver_priv, args->ctx_id);
if (IS_ERR(ctx))
return PTR_ERR(ctx);
/*
* We opt for unserialised reads here. This may result in tearing
* in the extremely unlikely event of a GPU hang on this context
* as we are querying them. If we need that extra layer of protection,
* we should wrap the hangstats with a seqlock.
*/
if (capable(CAP_SYS_ADMIN))
args->reset_count = i915_reset_count(&i915->gpu_error);
else
args->reset_count = 0;
args->batch_active = atomic_read(&ctx->guilty_count);
args->batch_pending = atomic_read(&ctx->active_count);
i915_gem_context_put(ctx);
return 0;
}
/* GEM context-engines iterator: for_each_gem_engine() */
struct intel_context *
i915_gem_engines_iter_next(struct i915_gem_engines_iter *it)
{
const struct i915_gem_engines *e = it->engines;
struct intel_context *ctx;
if (unlikely(!e))
return NULL;
do {
if (it->idx >= e->num_engines)
return NULL;
ctx = e->engines[it->idx++];
} while (!ctx);
return ctx;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
#include "selftests/mock_context.c"
#include "selftests/i915_gem_context.c"
#endif
void i915_gem_context_module_exit(void)
{
kmem_cache_destroy(slab_luts);
}
int __init i915_gem_context_module_init(void)
{
slab_luts = KMEM_CACHE(i915_lut_handle, 0);
if (!slab_luts)
return -ENOMEM;
return 0;
}