[PATCH v9 10/17] drm/i915/pxp: interfaces for using protected objects
Rodrigo Vivi
rodrigo.vivi at intel.com
Fri Sep 10 18:45:21 UTC 2021
On Fri, Sep 10, 2021 at 08:36:20AM -0700, Daniele Ceraolo Spurio wrote:
> This api allow user mode to create protected buffers and to mark
> contexts as making use of such objects. Only when using contexts
> marked in such a way is the execution guaranteed to work as expected.
>
> Contexts can only be marked as using protected content at creation time
> (i.e. the parameter is immutable) and they must be both bannable and not
> recoverable. Given that the protected session gets invalidated on
> suspend, contexts created this way hold a runtime pm wakeref until
> they're either destroyed or invalidated.
>
> All protected objects and contexts will be considered invalid when the
> PXP session is destroyed and all new submissions using them will be
> rejected. All intel contexts within the invalidated gem contexts will be
> marked banned. Userspace can detect that an invalidation has occurred via
> the RESET_STATS ioctl, where we report it the same way as a ban due to a
> hang.
>
> v5: squash patches, rebase on proto_ctx, update kerneldoc
>
> v6: rebase on obj create_ext changes
>
> v7: Use session counter to check if an object it valid, hold wakeref in
> context, don't add a new flag to RESET_STATS (Daniel)
>
> v8: don't increase guilty count for contexts banned during pxp
> invalidation (Rodrigo)
>
> v9: better comments, avoid wakeref put race between pxp_inval and
> context_close, add usage examples (Rodrigo)
>
> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
> Signed-off-by: Bommu Krishnaiah <krishnaiah.bommu at intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
> Cc: Jason Ekstrand <jason at jlekstrand.net>
> Cc: Daniel Vetter <daniel.vetter at intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> ---
> drivers/gpu/drm/i915/gem/i915_gem_context.c | 98 ++++++++++++++++---
> drivers/gpu/drm/i915/gem/i915_gem_context.h | 6 ++
> .../gpu/drm/i915/gem/i915_gem_context_types.h | 28 ++++++
> drivers/gpu/drm/i915/gem/i915_gem_create.c | 72 ++++++++++----
> .../gpu/drm/i915/gem/i915_gem_execbuffer.c | 18 ++++
> drivers/gpu/drm/i915/gem/i915_gem_object.c | 1 +
> drivers/gpu/drm/i915/gem/i915_gem_object.h | 6 ++
> .../gpu/drm/i915/gem/i915_gem_object_types.h | 8 ++
> .../gpu/drm/i915/gem/selftests/mock_context.c | 4 +-
> drivers/gpu/drm/i915/pxp/intel_pxp.c | 78 +++++++++++++++
> drivers/gpu/drm/i915/pxp/intel_pxp.h | 12 +++
> drivers/gpu/drm/i915/pxp/intel_pxp_session.c | 6 ++
> drivers/gpu/drm/i915/pxp/intel_pxp_types.h | 9 ++
> include/uapi/drm/i915_drm.h | 96 +++++++++++++++++-
> 14 files changed, 407 insertions(+), 35 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
> index c2ab0e22db0a..3418be4f727f 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
> @@ -77,6 +77,8 @@
> #include "gt/intel_gpu_commands.h"
> #include "gt/intel_ring.h"
>
> +#include "pxp/intel_pxp.h"
> +
> #include "i915_gem_context.h"
> #include "i915_trace.h"
> #include "i915_user_extensions.h"
> @@ -186,10 +188,13 @@ static int validate_priority(struct drm_i915_private *i915,
> return 0;
> }
>
> -static void proto_context_close(struct i915_gem_proto_context *pc)
> +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) {
> @@ -241,6 +246,33 @@ static int proto_context_set_persistence(struct drm_i915_private *i915,
> 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 (!intel_pxp_is_enabled(&i915->gt.pxp)) {
> + ret = -ENODEV;
> + } else if (!protected) {
> + pc->uses_protected_content = false;
> + } 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);
> + ret = intel_pxp_wait_for_arb_start(&i915->gt.pxp);
> + }
> +
> + return ret;
> +}
> +
> static struct i915_gem_proto_context *
> proto_context_create(struct drm_i915_private *i915, unsigned int flags)
> {
> @@ -269,7 +301,7 @@ proto_context_create(struct drm_i915_private *i915, unsigned int flags)
> return pc;
>
> proto_close:
> - proto_context_close(pc);
> + proto_context_close(i915, pc);
> return err;
> }
>
> @@ -693,6 +725,8 @@ static int set_proto_ctx_param(struct drm_i915_file_private *fpriv,
> 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;
> @@ -700,10 +734,12 @@ static int set_proto_ctx_param(struct drm_i915_file_private *fpriv,
> case I915_CONTEXT_PARAM_RECOVERABLE:
> if (args->size)
> ret = -EINVAL;
> - else if (args->value)
> - pc->user_flags |= BIT(UCONTEXT_RECOVERABLE);
> - else
> + 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:
> @@ -731,6 +767,11 @@ static int set_proto_ctx_param(struct drm_i915_file_private *fpriv,
> 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:
> @@ -956,6 +997,9 @@ static void i915_gem_context_release_work(struct work_struct *work)
> if (vm)
> i915_vm_put(vm);
>
> + if (ctx->pxp_wakeref)
> + intel_runtime_pm_put(&ctx->i915->runtime_pm, ctx->pxp_wakeref);
> +
> mutex_destroy(&ctx->engines_mutex);
> mutex_destroy(&ctx->lut_mutex);
>
> @@ -1338,6 +1382,11 @@ i915_gem_create_context(struct drm_i915_private *i915,
> 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;
> @@ -1409,7 +1458,7 @@ int i915_gem_context_open(struct drm_i915_private *i915,
> }
>
> ctx = i915_gem_create_context(i915, pc);
> - proto_context_close(pc);
> + proto_context_close(i915, pc);
> if (IS_ERR(ctx)) {
> err = PTR_ERR(ctx);
> goto err;
> @@ -1436,7 +1485,7 @@ void i915_gem_context_close(struct drm_file *file)
> unsigned long idx;
>
> xa_for_each(&file_priv->proto_context_xa, idx, pc)
> - proto_context_close(pc);
> + proto_context_close(file_priv->dev_priv, pc);
> xa_destroy(&file_priv->proto_context_xa);
> mutex_destroy(&file_priv->proto_context_lock);
>
> @@ -1731,6 +1780,18 @@ static int set_priority(struct i915_gem_context *ctx,
> return 0;
> }
>
> +static int get_protected(struct i915_gem_context *ctx,
> + struct drm_i915_gem_context_param *args)
> +{
> + if (!intel_pxp_is_enabled(&ctx->i915->gt.pxp))
> + return -ENODEV;
> +
> + 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)
> @@ -1754,6 +1815,8 @@ static int ctx_setparam(struct drm_i915_file_private *fpriv,
> 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;
> @@ -1761,10 +1824,12 @@ static int ctx_setparam(struct drm_i915_file_private *fpriv,
> case I915_CONTEXT_PARAM_RECOVERABLE:
> if (args->size)
> ret = -EINVAL;
> - else if (args->value)
> - i915_gem_context_set_recoverable(ctx);
> - else
> + 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:
> @@ -1779,6 +1844,7 @@ static int ctx_setparam(struct drm_i915_file_private *fpriv,
> 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:
> @@ -1857,7 +1923,7 @@ finalize_create_context_locked(struct drm_i915_file_private *file_priv,
>
> old = xa_erase(&file_priv->proto_context_xa, id);
> GEM_BUG_ON(old != pc);
> - proto_context_close(pc);
> + proto_context_close(file_priv->dev_priv, pc);
>
> /* One for the xarray and one for the caller */
> return i915_gem_context_get(ctx);
> @@ -1943,7 +2009,7 @@ int i915_gem_context_create_ioctl(struct drm_device *dev, void *data,
> goto err_pc;
> }
>
> - proto_context_close(ext_data.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);
> @@ -1957,7 +2023,7 @@ int i915_gem_context_create_ioctl(struct drm_device *dev, void *data,
> return 0;
>
> err_pc:
> - proto_context_close(ext_data.pc);
> + proto_context_close(i915, ext_data.pc);
> return ret;
> }
>
> @@ -1988,7 +2054,7 @@ int i915_gem_context_destroy_ioctl(struct drm_device *dev, void *data,
> GEM_WARN_ON(ctx && pc);
>
> if (pc)
> - proto_context_close(pc);
> + proto_context_close(file_priv->dev_priv, pc);
>
> if (ctx)
> context_close(ctx);
> @@ -2106,6 +2172,10 @@ int i915_gem_context_getparam_ioctl(struct drm_device *dev, void *data,
> 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:
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.h b/drivers/gpu/drm/i915/gem/i915_gem_context.h
> index d3279086a5e7..babfecb17ad1 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_context.h
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.h
> @@ -108,6 +108,12 @@ i915_gem_context_clear_user_engines(struct i915_gem_context *ctx)
> clear_bit(CONTEXT_USER_ENGINES, &ctx->flags);
> }
>
> +static inline bool
> +i915_gem_context_uses_protected_content(const struct i915_gem_context *ctx)
> +{
> + return ctx->uses_protected_content;
> +}
> +
> /* i915_gem_context.c */
> void i915_gem_init__contexts(struct drm_i915_private *i915);
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
> index c4617e4d9fa9..a627b09c4680 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
> @@ -198,6 +198,12 @@ struct i915_gem_proto_context {
>
> /** @single_timeline: See See &i915_gem_context.syncobj */
> bool single_timeline;
> +
> + /** @uses_protected_content: See &i915_gem_context.uses_protected_content */
> + bool uses_protected_content;
> +
> + /** @pxp_wakeref: See &i915_gem_context.pxp_wakeref */
> + intel_wakeref_t pxp_wakeref;
> };
>
> /**
> @@ -321,6 +327,28 @@ struct i915_gem_context {
> #define CONTEXT_CLOSED 0
> #define CONTEXT_USER_ENGINES 1
>
> + /**
> + * @uses_protected_content: context uses PXP-encrypted objects.
> + *
> + * This flag can only be set at ctx creation time and it's immutable for
> + * the lifetime of the context. See I915_CONTEXT_PARAM_PROTECTED_CONTENT
> + * in uapi/drm/i915_drm.h for more info on setting restrictions and
> + * expected behaviour of marked contexts.
> + */
> + bool uses_protected_content;
> +
> + /**
> + * @pxp_wakeref: wakeref to keep the device awake when PXP is in use
> + *
> + * PXP sessions are invalidated when the device is suspended, which in
> + * turns invalidates all contexts and objects using it. To keep the
> + * flow simple, we keep the device awake when contexts using PXP objects
> + * are in use. It is expected that the userspace application only uses
> + * PXP when the display is on, so taking a wakeref here shouldn't worsen
> + * our power metrics.
> + */
> + intel_wakeref_t pxp_wakeref;
> +
> /** @mutex: guards everything that isn't engines or handles_vma */
> struct mutex mutex;
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_create.c b/drivers/gpu/drm/i915/gem/i915_gem_create.c
> index 1d341b8c47c0..8955d6abcef1 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_create.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_create.c
> @@ -6,6 +6,7 @@
> #include "gem/i915_gem_ioctls.h"
> #include "gem/i915_gem_lmem.h"
> #include "gem/i915_gem_region.h"
> +#include "pxp/intel_pxp.h"
>
> #include "i915_drv.h"
> #include "i915_trace.h"
> @@ -82,21 +83,11 @@ static int i915_gem_publish(struct drm_i915_gem_object *obj,
> return 0;
> }
>
> -/**
> - * Creates a new object using the same path as DRM_I915_GEM_CREATE_EXT
> - * @i915: i915 private
> - * @size: size of the buffer, in bytes
> - * @placements: possible placement regions, in priority order
> - * @n_placements: number of possible placement regions
> - *
> - * This function is exposed primarily for selftests and does very little
> - * error checking. It is assumed that the set of placement regions has
> - * already been verified to be valid.
> - */
> -struct drm_i915_gem_object *
> -__i915_gem_object_create_user(struct drm_i915_private *i915, u64 size,
> - struct intel_memory_region **placements,
> - unsigned int n_placements)
> +static struct drm_i915_gem_object *
> +__i915_gem_object_create_user_ext(struct drm_i915_private *i915, u64 size,
> + struct intel_memory_region **placements,
> + unsigned int n_placements,
> + unsigned int ext_flags)
> {
> struct intel_memory_region *mr = placements[0];
> struct drm_i915_gem_object *obj;
> @@ -135,6 +126,9 @@ __i915_gem_object_create_user(struct drm_i915_private *i915, u64 size,
>
> GEM_BUG_ON(size != obj->base.size);
>
> + /* Add any flag set by create_ext options */
> + obj->flags |= ext_flags;
> +
> trace_i915_gem_object_create(obj);
> return obj;
>
> @@ -145,6 +139,26 @@ __i915_gem_object_create_user(struct drm_i915_private *i915, u64 size,
> return ERR_PTR(ret);
> }
>
> +/**
> + * Creates a new object using the same path as DRM_I915_GEM_CREATE_EXT
> + * @i915: i915 private
> + * @size: size of the buffer, in bytes
> + * @placements: possible placement regions, in priority order
> + * @n_placements: number of possible placement regions
> + *
> + * This function is exposed primarily for selftests and does very little
> + * error checking. It is assumed that the set of placement regions has
> + * already been verified to be valid.
> + */
> +struct drm_i915_gem_object *
> +__i915_gem_object_create_user(struct drm_i915_private *i915, u64 size,
> + struct intel_memory_region **placements,
> + unsigned int n_placements)
> +{
> + return __i915_gem_object_create_user_ext(i915, size, placements,
> + n_placements, 0);
> +}
> +
> int
> i915_gem_dumb_create(struct drm_file *file,
> struct drm_device *dev,
> @@ -224,6 +238,7 @@ struct create_ext {
> struct drm_i915_private *i915;
> struct intel_memory_region *placements[INTEL_REGION_UNKNOWN];
> unsigned int n_placements;
> + unsigned long flags;
> };
>
> static void repr_placements(char *buf, size_t size,
> @@ -353,8 +368,28 @@ static int ext_set_placements(struct i915_user_extension __user *base,
> return set_placements(&ext, data);
> }
>
> +static int ext_set_protected(struct i915_user_extension __user *base, void *data)
> +{
> + struct drm_i915_gem_create_ext_protected_content ext;
> + struct create_ext *ext_data = data;
> +
> + if (copy_from_user(&ext, base, sizeof(ext)))
> + return -EFAULT;
> +
> + if (ext.flags)
> + return -EINVAL;
> +
> + if (!intel_pxp_is_enabled(&ext_data->i915->gt.pxp))
> + return -ENODEV;
> +
> + ext_data->flags |= I915_BO_PROTECTED;
> +
> + return 0;
> +}
> +
> static const i915_user_extension_fn create_extensions[] = {
> [I915_GEM_CREATE_EXT_MEMORY_REGIONS] = ext_set_placements,
> + [I915_GEM_CREATE_EXT_PROTECTED_CONTENT] = ext_set_protected,
> };
>
> /**
> @@ -389,9 +424,10 @@ i915_gem_create_ext_ioctl(struct drm_device *dev, void *data,
> ext_data.n_placements = 1;
> }
>
> - obj = __i915_gem_object_create_user(i915, args->size,
> - ext_data.placements,
> - ext_data.n_placements);
> + obj = __i915_gem_object_create_user_ext(i915, args->size,
> + ext_data.placements,
> + ext_data.n_placements,
> + ext_data.flags);
> if (IS_ERR(obj))
> return PTR_ERR(obj);
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> index 2f2434b52317..d129a9f951da 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> @@ -21,6 +21,8 @@
> #include "gt/intel_gt_pm.h"
> #include "gt/intel_ring.h"
>
> +#include "pxp/intel_pxp.h"
> +
> #include "i915_drv.h"
> #include "i915_gem_clflush.h"
> #include "i915_gem_context.h"
> @@ -821,6 +823,22 @@ static struct i915_vma *eb_lookup_vma(struct i915_execbuffer *eb, u32 handle)
> if (unlikely(!obj))
> return ERR_PTR(-ENOENT);
>
> + /*
> + * If the user has opted-in for protected-object tracking, make
> + * sure the object encryption can be used.
> + * We only need to do this when the object is first used with
> + * this context, because the context itself will be banned when
> + * the protected objects become invalid.
> + */
> + if (i915_gem_context_uses_protected_content(eb->gem_context) &&
> + i915_gem_object_is_protected(obj)) {
> + err = intel_pxp_key_check(&vm->gt->pxp, obj);
> + if (err) {
> + i915_gem_object_put(obj);
> + return ERR_PTR(err);
> + }
> + }
> +
> vma = i915_vma_instance(obj, vm, NULL);
> if (IS_ERR(vma)) {
> i915_gem_object_put(obj);
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c
> index 6fb9afb65034..e85f2d9fddee 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_object.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c
> @@ -25,6 +25,7 @@
> #include <linux/sched/mm.h>
>
> #include "display/intel_frontbuffer.h"
> +#include "pxp/intel_pxp.h"
> #include "i915_drv.h"
> #include "i915_gem_clflush.h"
> #include "i915_gem_context.h"
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
> index 48112b9d76df..ed171daf49a7 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
> @@ -269,6 +269,12 @@ i915_gem_object_clear_tiling_quirk(struct drm_i915_gem_object *obj)
> clear_bit(I915_TILING_QUIRK_BIT, &obj->flags);
> }
>
> +static inline bool
> +i915_gem_object_is_protected(const struct drm_i915_gem_object *obj)
> +{
> + return obj->flags & I915_BO_PROTECTED;
> +}
> +
> static inline bool
> i915_gem_object_type_has(const struct drm_i915_gem_object *obj,
> unsigned long flags)
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
> index 2471f36aaff3..7d7e9c77f199 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
> @@ -298,6 +298,7 @@ struct drm_i915_gem_object {
> I915_BO_ALLOC_USER)
> #define I915_BO_READONLY BIT(4)
> #define I915_TILING_QUIRK_BIT 5 /* unknown swizzling; do not release! */
> +#define I915_BO_PROTECTED BIT(6)
>
> /**
> * @mem_flags - Mutable placement-related flags
> @@ -537,6 +538,13 @@ struct drm_i915_gem_object {
> bool created:1;
> } ttm;
>
> + /*
> + * Record which PXP key instance this object was created against (if
> + * any), so we can use it to determine if the encryption is valid by
> + * comparing against the current key instance.
> + */
> + u32 pxp_key_instance;
> +
> /** Record of address bit 17 of each page at last unbind. */
> unsigned long *bit_17;
>
> diff --git a/drivers/gpu/drm/i915/gem/selftests/mock_context.c b/drivers/gpu/drm/i915/gem/selftests/mock_context.c
> index 067d68a6fe4c..c0a8ef368044 100644
> --- a/drivers/gpu/drm/i915/gem/selftests/mock_context.c
> +++ b/drivers/gpu/drm/i915/gem/selftests/mock_context.c
> @@ -88,7 +88,7 @@ live_context(struct drm_i915_private *i915, struct file *file)
> return ERR_CAST(pc);
>
> ctx = i915_gem_create_context(i915, pc);
> - proto_context_close(pc);
> + proto_context_close(i915, pc);
> if (IS_ERR(ctx))
> return ctx;
>
> @@ -163,7 +163,7 @@ kernel_context(struct drm_i915_private *i915,
> }
>
> ctx = i915_gem_create_context(i915, pc);
> - proto_context_close(pc);
> + proto_context_close(i915, pc);
> if (IS_ERR(ctx))
> return ctx;
>
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.c b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> index b0c7edc10cc3..e49e60567a56 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> @@ -7,6 +7,7 @@
> #include "intel_pxp_irq.h"
> #include "intel_pxp_session.h"
> #include "intel_pxp_tee.h"
> +#include "gem/i915_gem_context.h"
> #include "gt/intel_context.h"
> #include "i915_drv.h"
>
> @@ -166,3 +167,80 @@ void intel_pxp_fini_hw(struct intel_pxp *pxp)
>
> intel_pxp_irq_disable(pxp);
> }
> +
> +int intel_pxp_key_check(struct intel_pxp *pxp, struct drm_i915_gem_object *obj)
> +{
> + if (!intel_pxp_is_active(pxp))
> + return -ENODEV;
> +
> + if (!i915_gem_object_is_protected(obj))
> + return -EINVAL;
> +
> + GEM_BUG_ON(!pxp->key_instance);
> +
> + /*
> + * If this is the first time we're using this object, it's not
> + * encrypted yet; it will be encrypted with the current key, so mark it
> + * as such. If the object is already encrypted, check instead if the
> + * used key is still valid.
> + */
> + if (!obj->pxp_key_instance)
> + obj->pxp_key_instance = pxp->key_instance;
> + else if (obj->pxp_key_instance != pxp->key_instance)
> + return -ENOEXEC;
> +
> + return 0;
> +}
> +
> +void intel_pxp_invalidate(struct intel_pxp *pxp)
> +{
> + struct drm_i915_private *i915 = pxp_to_gt(pxp)->i915;
> + struct i915_gem_context *ctx, *cn;
> +
> + /* ban all contexts marked as protected */
> + spin_lock_irq(&i915->gem.contexts.lock);
> + list_for_each_entry_safe(ctx, cn, &i915->gem.contexts.list, link) {
> + struct i915_gem_engines_iter it;
> + struct intel_context *ce;
> +
> + if (!kref_get_unless_zero(&ctx->ref))
> + continue;
> +
> + if (likely(!i915_gem_context_uses_protected_content(ctx))) {
> + i915_gem_context_put(ctx);
> + continue;
> + }
> +
> + spin_unlock_irq(&i915->gem.contexts.lock);
> +
> + /*
> + * By the time we get here we are either going to suspend with
> + * quiesced execution or the HW keys are already long gone and
> + * in this case it is worthless to attempt to close the context
> + * and wait for its execution. It will hang the GPU if it has
> + * not already. So, as a fast mitigation, we can ban the
> + * context as quick as we can. That might race with the
> + * execbuffer, but currently this is the best that can be done.
> + */
> + for_each_gem_engine(ce, i915_gem_context_lock_engines(ctx), it)
> + intel_context_ban(ce, NULL);
> + i915_gem_context_unlock_engines(ctx);
> +
> + /*
> + * The context has been banned, no need to keep the wakeref.
> + * This is safe from races because the only other place this
> + * is touched is context_release and we're holding a ctx ref
> + */
> + if (ctx->pxp_wakeref) {
> + intel_runtime_pm_put(&i915->runtime_pm,
> + ctx->pxp_wakeref);
> + ctx->pxp_wakeref = 0;
> + }
> +
> + spin_lock_irq(&i915->gem.contexts.lock);
> + list_safe_reset_next(ctx, cn, link);
> + i915_gem_context_put(ctx);
> + }
> + spin_unlock_irq(&i915->gem.contexts.lock);
> +}
> +
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.h b/drivers/gpu/drm/i915/pxp/intel_pxp.h
> index 8f1e86caa53f..f942bdd2af0c 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp.h
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.h
> @@ -9,6 +9,8 @@
> #include "gt/intel_gt_types.h"
> #include "intel_pxp_types.h"
>
> +struct drm_i915_gem_object;
> +
> static inline struct intel_gt *pxp_to_gt(const struct intel_pxp *pxp)
> {
> return container_of(pxp, struct intel_gt, pxp);
> @@ -33,6 +35,10 @@ void intel_pxp_fini_hw(struct intel_pxp *pxp);
>
> void intel_pxp_mark_termination_in_progress(struct intel_pxp *pxp);
> int intel_pxp_wait_for_arb_start(struct intel_pxp *pxp);
> +
> +int intel_pxp_key_check(struct intel_pxp *pxp, struct drm_i915_gem_object *obj);
> +
> +void intel_pxp_invalidate(struct intel_pxp *pxp);
> #else
> static inline void intel_pxp_init(struct intel_pxp *pxp)
> {
> @@ -46,6 +52,12 @@ static inline int intel_pxp_wait_for_arb_start(struct intel_pxp *pxp)
> {
> return -ENODEV;
> }
> +
> +static inline int intel_pxp_key_check(struct intel_pxp *pxp,
> + struct drm_i915_gem_object *obj)
> +{
> + return -ENODEV;
> +}
> #endif
>
> #endif /* __INTEL_PXP_H__ */
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> index 67c30e534d50..c6a5e4197e40 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> @@ -72,6 +72,9 @@ static int pxp_create_arb_session(struct intel_pxp *pxp)
> return ret;
> }
>
> + if (!++pxp->key_instance)
> + ++pxp->key_instance;
> +
> pxp->arb_is_valid = true;
>
> return 0;
> @@ -85,6 +88,9 @@ static int pxp_terminate_arb_session_and_global(struct intel_pxp *pxp)
> /* must mark termination in progress calling this function */
> GEM_WARN_ON(pxp->arb_is_valid);
>
> + /* invalidate protected objects */
> + intel_pxp_invalidate(pxp);
> +
> /* terminate the hw sessions */
> ret = intel_pxp_terminate_session(pxp, ARB_SESSION);
> if (ret) {
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_types.h b/drivers/gpu/drm/i915/pxp/intel_pxp_types.h
> index 5a170e43c959..c394ab2e452b 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_types.h
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_types.h
> @@ -7,7 +7,9 @@
> #define __INTEL_PXP_TYPES_H__
>
> #include <linux/completion.h>
> +#include <linux/list.h>
> #include <linux/mutex.h>
> +#include <linux/spinlock.h>
> #include <linux/types.h>
> #include <linux/workqueue.h>
>
> @@ -27,6 +29,13 @@ struct intel_pxp {
> */
> bool arb_is_valid;
>
> + /*
> + * Keep track of which key instance we're on, so we can use it to
> + * determine if an object was created using the current key or a
> + * previous one.
> + */
> + u32 key_instance;
> +
> struct mutex tee_mutex; /* protects the tee channel binding */
>
> /*
> diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
> index 920e9e852e5a..3fab202ca754 100644
> --- a/include/uapi/drm/i915_drm.h
> +++ b/include/uapi/drm/i915_drm.h
> @@ -1846,12 +1846,61 @@ struct drm_i915_gem_context_param {
> * attempted to use it, never re-use this context param number.
> */
> #define I915_CONTEXT_PARAM_RINGSIZE 0xc
> +
> +/*
> + * I915_CONTEXT_PARAM_PROTECTED_CONTENT:
> + *
> + * Mark that the context makes use of protected content, which will result
> + * in the context being invalidated when the protected content session is.
> + * Given that the protected content session is killed on suspend, the device
> + * is kept awake for the lifetime of a protected context, so the user should
> + * make sure to dispose of them once done.
> + * This flag can only be set at context creation time and, when set to true,
> + * must be preceded by an explicit setting of I915_CONTEXT_PARAM_RECOVERABLE
> + * to false. This flag can't be set to true in conjunction with setting the
> + * I915_CONTEXT_PARAM_BANNABLE flag to false. Creation example:
> + *
> + * .. code-block:: C
> + *
> + * struct drm_i915_gem_context_create_ext_setparam p_protected = {
> + * .base = {
> + * .name = I915_CONTEXT_CREATE_EXT_SETPARAM,
> + * },
> + * .param = {
> + * .param = I915_CONTEXT_PARAM_PROTECTED_CONTENT,
> + * .value = 1,
> + * }
> + * };
> + * struct drm_i915_gem_context_create_ext_setparam p_norecover = {
> + * .base = {
> + * .name = I915_CONTEXT_CREATE_EXT_SETPARAM,
> + * .next_extension = to_user_pointer(&p_protected),
> + * },
> + * .param = {
> + * .param = I915_CONTEXT_PARAM_RECOVERABLE,
> + * .value = 0,
> + * }
> + * };
> + * struct drm_i915_gem_context_create_ext create = {
> + * .flags = I915_CONTEXT_CREATE_FLAGS_USE_EXTENSIONS,
> + * .extensions = to_user_pointer(&p_norecover);
> + * };
> + *
> + * ctx_id = gem_context_create_ext(drm_fd, &create);
> + *
> + * In addition to the normal failure cases, setting this flag during context
> + * creation can result in the following errors:
> + *
> + * -ENODEV: feature not available
> + * -EPERM: trying to mark a recoverable or not bannable context as protected
> + */
> +#define I915_CONTEXT_PARAM_PROTECTED_CONTENT 0xd
> /* Must be kept compact -- no holes and well documented */
>
> __u64 value;
> };
>
> -/*
> +/**
> * Context SSEU programming
> *
> * It may be necessary for either functional or performance reason to configure
> @@ -2979,8 +3028,12 @@ struct drm_i915_gem_create_ext {
> *
> * For I915_GEM_CREATE_EXT_MEMORY_REGIONS usage see
> * struct drm_i915_gem_create_ext_memory_regions.
> + *
> + * For I915_GEM_CREATE_EXT_PROTECTED_CONTENT usage see
> + * struct drm_i915_gem_create_ext_protected_content.
> */
> #define I915_GEM_CREATE_EXT_MEMORY_REGIONS 0
> +#define I915_GEM_CREATE_EXT_PROTECTED_CONTENT 1
> __u64 extensions;
> };
>
> @@ -3038,6 +3091,47 @@ struct drm_i915_gem_create_ext_memory_regions {
> __u64 regions;
> };
>
> +/**
> + * struct drm_i915_gem_create_ext_protected_content - The
> + * I915_OBJECT_PARAM_PROTECTED_CONTENT extension.
> + *
> + * If this extension is provided, buffer contents are expected to be protected
> + * by PXP encryption and require decryption for scan out and processing. This
> + * is only possible on platforms that have PXP enabled, on all other scenarios
> + * using this extension will cause the ioctl to fail and return -ENODEV. The
> + * flags parameter is reserved for future expansion and must currently be set
> + * to zero.
> + *
> + * The buffer contents are considered invalid after a PXP session teardown.
> + *
> + * The encryption is guaranteed to be processed correctly only if the object
> + * is submitted with a context created using the
> + * I915_CONTEXT_PARAM_PROTECTED_CONTENT flag. This will also enable extra checks
> + * at submission time on the validity of the objects involved.
> + *
> + * Below is an example on how to create a protected object:
> + *
> + * .. code-block:: C
> + *
> + * struct drm_i915_gem_create_ext_protected_content protected_ext = {
> + * .base = { .name = I915_GEM_CREATE_EXT_PROTECTED_CONTENT },
> + * .flags = 0,
> + * };
> + * struct drm_i915_gem_create_ext create_ext = {
> + * .size = PAGE_SIZE,
> + * .extensions = (uintptr_t)&protected_ext,
> + * };
> + *
> + * int err = ioctl(fd, DRM_IOCTL_I915_GEM_CREATE_EXT, &create_ext);
> + * if (err) ...
> + */
> +struct drm_i915_gem_create_ext_protected_content {
> + /** @base: Extension link. See struct i915_user_extension. */
> + struct i915_user_extension base;
> + /** @flags: reserved for future usage, currently MBZ */
> + __u32 flags;
> +};
> +
> /* ID of the protected content session managed by i915 when PXP is active */
> #define I915_PROTECTED_CONTENT_DEFAULT_SESSION 0xf
>
> --
> 2.25.1
>
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