Gentle Reminder!
Regards,
Suraj Kandpal
> -----Original Message-----
> From: Kandpal, Suraj <suraj.kandpal@xxxxxxxxx>
> Sent: Monday, May 29, 2023 5:19 PM
> To: intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> Cc: Kandpal, Suraj <suraj.kandpal@xxxxxxxxx>; Nautiyal, Ankit K
> <ankit.k.nautiyal@xxxxxxxxx>; Teres Alexis, Alan Previn
> <alan.previn.teres.alexis@xxxxxxxxx>; Ceraolo Spurio, Daniele
> <daniele.ceraolospurio@xxxxxxxxx>
> Subject: [PATCH 1/2] drm/i915/hdcp: Allocate a multipage object to
> hdcp_gsc_message
>
> Allocate a multipage object that can be used for input and output for
> intel_hdcp_gsc_message so that corruption of output message can be
> avoided by the current overwriting method.
>
> --v2
> -Change approach from allocating two objects to just one multipage object
> [Daniele]
>
> Cc: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx>
> Cc: Alan Previn <alan.previn.teres.alexis@xxxxxxxxx>
> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@xxxxxxxxx>
> Signed-off-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_hdcp_gsc.c | 55 +++++++++++--------
> drivers/gpu/drm/i915/display/intel_hdcp_gsc.h | 3 +-
> 2 files changed, 34 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_hdcp_gsc.c
> b/drivers/gpu/drm/i915/display/intel_hdcp_gsc.c
> index 7e52aea6aa17..72d1e261d0a9 100644
> --- a/drivers/gpu/drm/i915/display/intel_hdcp_gsc.c
> +++ b/drivers/gpu/drm/i915/display/intel_hdcp_gsc.c
> @@ -621,24 +621,26 @@ static int intel_hdcp_gsc_initialize_message(struct
> drm_i915_private *i915,
> struct intel_gt *gt = i915->media_gt;
> struct drm_i915_gem_object *obj = NULL;
> struct i915_vma *vma = NULL;
> - void *cmd;
> + void *cmd_in, *cmd_out;
> int err;
>
> - /* allocate object of one page for HDCP command memory and store
> it */
> - obj = i915_gem_object_create_shmem(i915, PAGE_SIZE);
> + /* allocate object of two page for HDCP command memory and store
> it */
> + obj = i915_gem_object_create_shmem(i915, 2 * PAGE_SIZE);
>
> if (IS_ERR(obj)) {
> drm_err(&i915->drm, "Failed to allocate HDCP streaming
> command!\n");
> return PTR_ERR(obj);
> }
>
> - cmd = i915_gem_object_pin_map_unlocked(obj,
> i915_coherent_map_type(i915, obj, true));
> - if (IS_ERR(cmd)) {
> + cmd_in = i915_gem_object_pin_map_unlocked(obj,
> i915_coherent_map_type(i915, obj, true));
> + if (IS_ERR(cmd_in)) {
> drm_err(&i915->drm, "Failed to map gsc message page!\n");
> - err = PTR_ERR(cmd);
> + err = PTR_ERR(cmd_in);
> goto out_unpin;
> }
>
> + cmd_out = cmd_in + PAGE_SIZE;
> +
> vma = i915_vma_instance(obj, >->ggtt->vm, NULL);
> if (IS_ERR(vma)) {
> err = PTR_ERR(vma);
> @@ -649,9 +651,10 @@ static int intel_hdcp_gsc_initialize_message(struct
> drm_i915_private *i915,
> if (err)
> goto out_unmap;
>
> - memset(cmd, 0, obj->base.size);
> + memset(cmd_in, 0, obj->base.size);
>
> - hdcp_message->hdcp_cmd = cmd;
> + hdcp_message->hdcp_cmd_in = cmd_in;
> + hdcp_message->hdcp_cmd_out = cmd_out;
> hdcp_message->vma = vma;
>
> return 0;
> @@ -668,7 +671,7 @@ static int intel_hdcp_gsc_hdcp2_init(struct
> drm_i915_private *i915)
> struct intel_hdcp_gsc_message *hdcp_message;
> int ret;
>
> - hdcp_message = kzalloc(sizeof(*hdcp_message), GFP_KERNEL);
> + hdcp_message = kzalloc(2 * sizeof(*hdcp_message), GFP_KERNEL);
>
> if (!hdcp_message)
> return -ENOMEM;
> @@ -691,6 +694,8 @@ static void intel_hdcp_gsc_free_message(struct
> drm_i915_private *i915)
> struct intel_hdcp_gsc_message *hdcp_message =
> i915->display.hdcp.hdcp_message;
>
> + hdcp_message->hdcp_cmd_in = NULL;
> + hdcp_message->hdcp_cmd_out = NULL;
> i915_vma_unpin_and_release(&hdcp_message->vma,
> I915_VMA_RELEASE_MAP);
> kfree(hdcp_message);
> }
> @@ -769,11 +774,11 @@ ssize_t intel_hdcp_gsc_msg_send(struct
> drm_i915_private *i915, u8 *msg_in,
> size_t msg_out_len)
> {
> struct intel_gt *gt = i915->media_gt;
> - struct intel_gsc_mtl_header *header;
> - const size_t max_msg_size = PAGE_SIZE - sizeof(*header);
> + struct intel_gsc_mtl_header *header_in, *header_out;
> + const size_t max_msg_size = PAGE_SIZE - sizeof(*header_in);
> struct intel_hdcp_gsc_message *hdcp_message;
> - u64 addr, host_session_id;
> - u32 reply_size, msg_size;
> + u64 addr_in, addr_out, host_session_id;
> + u32 reply_size, msg_size_in, msg_size_out;
> int ret, tries = 0;
>
> if (!intel_uc_uses_gsc_uc(>->uc))
> @@ -782,16 +787,20 @@ ssize_t intel_hdcp_gsc_msg_send(struct
> drm_i915_private *i915, u8 *msg_in,
> if (msg_in_len > max_msg_size || msg_out_len > max_msg_size)
> return -ENOSPC;
>
> + msg_size_in = msg_in_len + sizeof(*header_in);
> + msg_size_out = msg_out_len + sizeof(*header_out);
> hdcp_message = i915->display.hdcp.hdcp_message;
> - header = hdcp_message->hdcp_cmd;
> - addr = i915_ggtt_offset(hdcp_message->vma);
> + header_in = hdcp_message->hdcp_cmd_in;
> + header_out = hdcp_message->hdcp_cmd_out;
> + addr_in = i915_ggtt_offset(hdcp_message->vma);
> + addr_out = addr_in + PAGE_SIZE;
>
> - msg_size = msg_in_len + sizeof(*header);
> - memset(header, 0, msg_size);
> + memset(header_in, 0, msg_size_in);
> + memset(header_out, 0, msg_size_out);
> get_random_bytes(&host_session_id, sizeof(u64));
> - intel_gsc_uc_heci_cmd_emit_mtl_header(header,
> HECI_MEADDRESS_HDCP,
> - msg_size, host_session_id);
> - memcpy(hdcp_message->hdcp_cmd + sizeof(*header), msg_in,
> msg_in_len);
> + intel_gsc_uc_heci_cmd_emit_mtl_header(header_in,
> HECI_MEADDRESS_HDCP,
> + msg_size_in, host_session_id);
> + memcpy(hdcp_message->hdcp_cmd_in + sizeof(*header_in),
> msg_in,
> +msg_in_len);
>
> /*
> * Keep sending request in case the pending bit is set no need to add
> @@ -800,7 +809,7 @@ ssize_t intel_hdcp_gsc_msg_send(struct
> drm_i915_private *i915, u8 *msg_in,
> * 20 times each message 50 ms apart
> */
> do {
> - ret = intel_gsc_send_sync(i915, header, addr, msg_out_len);
> + ret = intel_gsc_send_sync(i915, header_in, addr_in,
> msg_out_len);
>
> /* Only try again if gsc says so */
> if (ret != -EAGAIN)
> @@ -814,7 +823,7 @@ ssize_t intel_hdcp_gsc_msg_send(struct
> drm_i915_private *i915, u8 *msg_in,
> goto err;
>
> /* we use the same mem for the reply, so header is in the same loc
> */
> - reply_size = header->message_size - sizeof(*header);
> + reply_size = header_out->message_size - sizeof(*header_out);
> if (reply_size > msg_out_len) {
> drm_warn(&i915->drm, "caller with insufficient HDCP reply
> size %u (%d)\n",
> reply_size, (u32)msg_out_len);
> @@ -824,7 +833,7 @@ ssize_t intel_hdcp_gsc_msg_send(struct
> drm_i915_private *i915, u8 *msg_in,
> reply_size, (u32)msg_out_len);
> }
>
> - memcpy(msg_out, hdcp_message->hdcp_cmd + sizeof(*header),
> msg_out_len);
> + memcpy(msg_out, hdcp_message->hdcp_cmd_out +
> sizeof(*header_out),
> +msg_out_len);
>
> err:
> return ret;
> diff --git a/drivers/gpu/drm/i915/display/intel_hdcp_gsc.h
> b/drivers/gpu/drm/i915/display/intel_hdcp_gsc.h
> index 5cc9fd2e88f6..cbf96551e534 100644
> --- a/drivers/gpu/drm/i915/display/intel_hdcp_gsc.h
> +++ b/drivers/gpu/drm/i915/display/intel_hdcp_gsc.h
> @@ -13,7 +13,8 @@ struct drm_i915_private;
>
> struct intel_hdcp_gsc_message {
> struct i915_vma *vma;
> - void *hdcp_cmd;
> + void *hdcp_cmd_in;
> + void *hdcp_cmd_out;
> };
>
> bool intel_hdcp_gsc_cs_required(struct drm_i915_private *i915);
> --
> 2.25.1
