[PATCH v13 06/24] gunyah: rsc_mgr: Add resource manager RPC core
Srinivas Kandagatla
srinivas.kandagatla at linaro.org
Tue Jun 6 05:45:13 PDT 2023
On 09/05/2023 21:47, Elliot Berman wrote:
> The resource manager is a special virtual machine which is always
> running on a Gunyah system. It provides APIs for creating and destroying
> VMs, secure memory management, sharing/lending of memory between VMs,
> and setup of inter-VM communication. Calls to the resource manager are
> made via message queues.
>
> This patch implements the basic probing and RPC mechanism to make those
> API calls. Request/response calls can be made with gh_rm_call.
> Drivers can also register to notifications pushed by RM via
> gh_rm_register_notifier
>
> Specific API calls that resource manager supports will be implemented in
> subsequent patches.
>
> Signed-off-by: Elliot Berman <quic_eberman at quicinc.com>
> ---
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla at linaro.org>
--srini
> drivers/virt/Makefile | 1 +
> drivers/virt/gunyah/Makefile | 4 +
> drivers/virt/gunyah/rsc_mgr.c | 702 +++++++++++++++++++++++++++++++++
> drivers/virt/gunyah/rsc_mgr.h | 16 +
> include/linux/gunyah_rsc_mgr.h | 21 +
> 5 files changed, 744 insertions(+)
> create mode 100644 drivers/virt/gunyah/Makefile
> create mode 100644 drivers/virt/gunyah/rsc_mgr.c
> create mode 100644 drivers/virt/gunyah/rsc_mgr.h
> create mode 100644 include/linux/gunyah_rsc_mgr.h
>
> diff --git a/drivers/virt/Makefile b/drivers/virt/Makefile
> index e9aa6fc96fab..a5817e2d7d71 100644
> --- a/drivers/virt/Makefile
> +++ b/drivers/virt/Makefile
> @@ -12,3 +12,4 @@ obj-$(CONFIG_ACRN_HSM) += acrn/
> obj-$(CONFIG_EFI_SECRET) += coco/efi_secret/
> obj-$(CONFIG_SEV_GUEST) += coco/sev-guest/
> obj-$(CONFIG_INTEL_TDX_GUEST) += coco/tdx-guest/
> +obj-y += gunyah/
> diff --git a/drivers/virt/gunyah/Makefile b/drivers/virt/gunyah/Makefile
> new file mode 100644
> index 000000000000..0f5aec834698
> --- /dev/null
> +++ b/drivers/virt/gunyah/Makefile
> @@ -0,0 +1,4 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +gunyah-y += rsc_mgr.o
> +obj-$(CONFIG_GUNYAH) += gunyah.o
> diff --git a/drivers/virt/gunyah/rsc_mgr.c b/drivers/virt/gunyah/rsc_mgr.c
> new file mode 100644
> index 000000000000..88b5beb1ea51
> --- /dev/null
> +++ b/drivers/virt/gunyah/rsc_mgr.c
> @@ -0,0 +1,702 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
> + */
> +
> +#include <linux/of.h>
> +#include <linux/slab.h>
> +#include <linux/mutex.h>
> +#include <linux/sched.h>
> +#include <linux/gunyah.h>
> +#include <linux/module.h>
> +#include <linux/of_irq.h>
> +#include <linux/notifier.h>
> +#include <linux/workqueue.h>
> +#include <linux/completion.h>
> +#include <linux/gunyah_rsc_mgr.h>
> +#include <linux/platform_device.h>
> +
> +#include "rsc_mgr.h"
> +
> +#define RM_RPC_API_VERSION_MASK GENMASK(3, 0)
> +#define RM_RPC_HEADER_WORDS_MASK GENMASK(7, 4)
> +#define RM_RPC_API_VERSION FIELD_PREP(RM_RPC_API_VERSION_MASK, 1)
> +#define RM_RPC_HEADER_WORDS FIELD_PREP(RM_RPC_HEADER_WORDS_MASK, \
> + (sizeof(struct gh_rm_rpc_hdr) / sizeof(u32)))
> +#define RM_RPC_API (RM_RPC_API_VERSION | RM_RPC_HEADER_WORDS)
> +
> +#define RM_RPC_TYPE_CONTINUATION 0x0
> +#define RM_RPC_TYPE_REQUEST 0x1
> +#define RM_RPC_TYPE_REPLY 0x2
> +#define RM_RPC_TYPE_NOTIF 0x3
> +#define RM_RPC_TYPE_MASK GENMASK(1, 0)
> +
> +#define GH_RM_MAX_NUM_FRAGMENTS 62
> +#define RM_RPC_FRAGMENTS_MASK GENMASK(7, 2)
> +
> +struct gh_rm_rpc_hdr {
> + u8 api;
> + u8 type;
> + __le16 seq;
> + __le32 msg_id;
> +} __packed;
> +
> +struct gh_rm_rpc_reply_hdr {
> + struct gh_rm_rpc_hdr hdr;
> + __le32 err_code; /* GH_RM_ERROR_* */
> +} __packed;
> +
> +#define GH_RM_MAX_MSG_SIZE (GH_MSGQ_MAX_MSG_SIZE - sizeof(struct gh_rm_rpc_hdr))
> +
> +/* RM Error codes */
> +enum gh_rm_error {
> + GH_RM_ERROR_OK = 0x0,
> + GH_RM_ERROR_UNIMPLEMENTED = 0xFFFFFFFF,
> + GH_RM_ERROR_NOMEM = 0x1,
> + GH_RM_ERROR_NORESOURCE = 0x2,
> + GH_RM_ERROR_DENIED = 0x3,
> + GH_RM_ERROR_INVALID = 0x4,
> + GH_RM_ERROR_BUSY = 0x5,
> + GH_RM_ERROR_ARGUMENT_INVALID = 0x6,
> + GH_RM_ERROR_HANDLE_INVALID = 0x7,
> + GH_RM_ERROR_VALIDATE_FAILED = 0x8,
> + GH_RM_ERROR_MAP_FAILED = 0x9,
> + GH_RM_ERROR_MEM_INVALID = 0xA,
> + GH_RM_ERROR_MEM_INUSE = 0xB,
> + GH_RM_ERROR_MEM_RELEASED = 0xC,
> + GH_RM_ERROR_VMID_INVALID = 0xD,
> + GH_RM_ERROR_LOOKUP_FAILED = 0xE,
> + GH_RM_ERROR_IRQ_INVALID = 0xF,
> + GH_RM_ERROR_IRQ_INUSE = 0x10,
> + GH_RM_ERROR_IRQ_RELEASED = 0x11,
> +};
> +
> +/**
> + * struct gh_rm_connection - Represents a complete message from resource manager
> + * @payload: Combined payload of all the fragments (msg headers stripped off).
> + * @size: Size of the payload received so far.
> + * @msg_id: Message ID from the header.
> + * @type: RM_RPC_TYPE_REPLY or RM_RPC_TYPE_NOTIF.
> + * @num_fragments: total number of fragments expected to be received.
> + * @fragments_received: fragments received so far.
> + * @reply: Fields used for request/reply sequences
> + * @notification: Fields used for notifiations
> + */
> +struct gh_rm_connection {
> + void *payload;
> + size_t size;
> + __le32 msg_id;
> + u8 type;
> +
> + u8 num_fragments;
> + u8 fragments_received;
> +
> + union {
> + /**
> + * @ret: Linux return code, there was an error processing connection
> + * @seq: Sequence ID for the main message.
> + * @rm_error: For request/reply sequences with standard replies
> + * @seq_done: Signals caller that the RM reply has been received
> + */
> + struct {
> + int ret;
> + u16 seq;
> + enum gh_rm_error rm_error;
> + struct completion seq_done;
> + } reply;
> +
> + /**
> + * @rm: Pointer to the RM that launched the connection
> + * @work: Triggered when all fragments of a notification received
> + */
> + struct {
> + struct gh_rm *rm;
> + struct work_struct work;
> + } notification;
> + };
> +};
> +
> +/**
> + * struct gh_rm - private data for communicating w/Gunyah resource manager
> + * @dev: pointer to device
> + * @tx_ghrsc: message queue resource to TX to RM
> + * @rx_ghrsc: message queue resource to RX from RM
> + * @msgq: mailbox instance of TX/RX resources above
> + * @msgq_client: mailbox client of above msgq
> + * @active_rx_connection: ongoing gh_rm_connection for which we're receiving fragments
> + * @last_tx_ret: return value of last mailbox tx
> + * @call_xarray: xarray to allocate & lookup sequence IDs for Request/Response flows
> + * @next_seq: next ID to allocate (for xa_alloc_cyclic)
> + * @cache: cache for allocating Tx messages
> + * @send_lock: synchronization to allow only one request to be sent at a time
> + * @nh: notifier chain for clients interested in RM notification messages
> + */
> +struct gh_rm {
> + struct device *dev;
> + struct gh_resource tx_ghrsc;
> + struct gh_resource rx_ghrsc;
> + struct gh_msgq msgq;
> + struct mbox_client msgq_client;
> + struct gh_rm_connection *active_rx_connection;
> + int last_tx_ret;
> +
> + struct xarray call_xarray;
> + u32 next_seq;
> +
> + struct kmem_cache *cache;
> + struct mutex send_lock;
> + struct blocking_notifier_head nh;
> +};
> +
> +/**
> + * gh_rm_remap_error() - Remap Gunyah resource manager errors into a Linux error code
> + * @rm_error: "Standard" return value from Gunyah resource manager
> + */
> +static inline int gh_rm_remap_error(enum gh_rm_error rm_error)
> +{
> + switch (rm_error) {
> + case GH_RM_ERROR_OK:
> + return 0;
> + case GH_RM_ERROR_UNIMPLEMENTED:
> + return -EOPNOTSUPP;
> + case GH_RM_ERROR_NOMEM:
> + return -ENOMEM;
> + case GH_RM_ERROR_NORESOURCE:
> + return -ENODEV;
> + case GH_RM_ERROR_DENIED:
> + return -EPERM;
> + case GH_RM_ERROR_BUSY:
> + return -EBUSY;
> + case GH_RM_ERROR_INVALID:
> + case GH_RM_ERROR_ARGUMENT_INVALID:
> + case GH_RM_ERROR_HANDLE_INVALID:
> + case GH_RM_ERROR_VALIDATE_FAILED:
> + case GH_RM_ERROR_MAP_FAILED:
> + case GH_RM_ERROR_MEM_INVALID:
> + case GH_RM_ERROR_MEM_INUSE:
> + case GH_RM_ERROR_MEM_RELEASED:
> + case GH_RM_ERROR_VMID_INVALID:
> + case GH_RM_ERROR_LOOKUP_FAILED:
> + case GH_RM_ERROR_IRQ_INVALID:
> + case GH_RM_ERROR_IRQ_INUSE:
> + case GH_RM_ERROR_IRQ_RELEASED:
> + return -EINVAL;
> + default:
> + return -EBADMSG;
> + }
> +}
> +
> +static int gh_rm_init_connection_payload(struct gh_rm_connection *connection, void *msg,
> + size_t hdr_size, size_t msg_size)
> +{
> + size_t max_buf_size, payload_size;
> + struct gh_rm_rpc_hdr *hdr = msg;
> +
> + if (msg_size < hdr_size)
> + return -EINVAL;
> +
> + payload_size = msg_size - hdr_size;
> +
> + connection->num_fragments = FIELD_GET(RM_RPC_FRAGMENTS_MASK, hdr->type);
> + connection->fragments_received = 0;
> +
> + /* There's not going to be any payload, no need to allocate buffer. */
> + if (!payload_size && !connection->num_fragments)
> + return 0;
> +
> + if (connection->num_fragments > GH_RM_MAX_NUM_FRAGMENTS)
> + return -EINVAL;
> +
> + max_buf_size = payload_size + (connection->num_fragments * GH_RM_MAX_MSG_SIZE);
> +
> + connection->payload = kzalloc(max_buf_size, GFP_KERNEL);
> + if (!connection->payload)
> + return -ENOMEM;
> +
> + memcpy(connection->payload, msg + hdr_size, payload_size);
> + connection->size = payload_size;
> + return 0;
> +}
> +
> +static void gh_rm_abort_connection(struct gh_rm *rm)
> +{
> + switch (rm->active_rx_connection->type) {
> + case RM_RPC_TYPE_REPLY:
> + rm->active_rx_connection->reply.ret = -EIO;
> + complete(&rm->active_rx_connection->reply.seq_done);
> + break;
> + case RM_RPC_TYPE_NOTIF:
> + fallthrough;
> + default:
> + kfree(rm->active_rx_connection->payload);
> + kfree(rm->active_rx_connection);
> + }
> +
> + rm->active_rx_connection = NULL;
> +}
> +
> +static void gh_rm_notif_work(struct work_struct *work)
> +{
> + struct gh_rm_connection *connection = container_of(work, struct gh_rm_connection,
> + notification.work);
> + struct gh_rm *rm = connection->notification.rm;
> +
> + blocking_notifier_call_chain(&rm->nh, le32_to_cpu(connection->msg_id), connection->payload);
> +
> + put_device(rm->dev);
> + kfree(connection->payload);
> + kfree(connection);
> +}
> +
> +static void gh_rm_process_notif(struct gh_rm *rm, void *msg, size_t msg_size)
> +{
> + struct gh_rm_connection *connection;
> + struct gh_rm_rpc_hdr *hdr = msg;
> + int ret;
> +
> + if (rm->active_rx_connection)
> + gh_rm_abort_connection(rm);
> +
> + connection = kzalloc(sizeof(*connection), GFP_KERNEL);
> + if (!connection)
> + return;
> +
> + connection->type = RM_RPC_TYPE_NOTIF;
> + connection->msg_id = hdr->msg_id;
> +
> + get_device(rm->dev);
> + connection->notification.rm = rm;
> + INIT_WORK(&connection->notification.work, gh_rm_notif_work);
> +
> + ret = gh_rm_init_connection_payload(connection, msg, sizeof(*hdr), msg_size);
> + if (ret) {
> + dev_err(rm->dev, "Failed to initialize connection for notification: %d\n", ret);
> + put_device(rm->dev);
> + kfree(connection);
> + return;
> + }
> +
> + rm->active_rx_connection = connection;
> +}
> +
> +static void gh_rm_process_rply(struct gh_rm *rm, void *msg, size_t msg_size)
> +{
> + struct gh_rm_rpc_reply_hdr *reply_hdr = msg;
> + struct gh_rm_connection *connection;
> + u16 seq_id;
> +
> + seq_id = le16_to_cpu(reply_hdr->hdr.seq);
> + connection = xa_load(&rm->call_xarray, seq_id);
> +
> + if (!connection || connection->msg_id != reply_hdr->hdr.msg_id)
> + return;
> +
> + if (rm->active_rx_connection)
> + gh_rm_abort_connection(rm);
> +
> + if (gh_rm_init_connection_payload(connection, msg, sizeof(*reply_hdr), msg_size)) {
> + dev_err(rm->dev, "Failed to alloc connection buffer for sequence %d\n", seq_id);
> + /* Send connection complete and error the client. */
> + connection->reply.ret = -ENOMEM;
> + complete(&connection->reply.seq_done);
> + return;
> + }
> +
> + connection->reply.rm_error = le32_to_cpu(reply_hdr->err_code);
> + rm->active_rx_connection = connection;
> +}
> +
> +static void gh_rm_process_cont(struct gh_rm *rm, struct gh_rm_connection *connection,
> + void *msg, size_t msg_size)
> +{
> + struct gh_rm_rpc_hdr *hdr = msg;
> + size_t payload_size = msg_size - sizeof(*hdr);
> +
> + if (!rm->active_rx_connection)
> + return;
> +
> + /*
> + * hdr->fragments and hdr->msg_id preserves the value from first reply
> + * or notif message. To detect mishandling, check it's still intact.
> + */
> + if (connection->msg_id != hdr->msg_id ||
> + connection->num_fragments != FIELD_GET(RM_RPC_FRAGMENTS_MASK, hdr->type)) {
> + gh_rm_abort_connection(rm);
> + return;
> + }
> +
> + memcpy(connection->payload + connection->size, msg + sizeof(*hdr), payload_size);
> + connection->size += payload_size;
> + connection->fragments_received++;
> +}
> +
> +static void gh_rm_try_complete_connection(struct gh_rm *rm)
> +{
> + struct gh_rm_connection *connection = rm->active_rx_connection;
> +
> + if (!connection || connection->fragments_received != connection->num_fragments)
> + return;
> +
> + switch (connection->type) {
> + case RM_RPC_TYPE_REPLY:
> + complete(&connection->reply.seq_done);
> + break;
> + case RM_RPC_TYPE_NOTIF:
> + schedule_work(&connection->notification.work);
> + break;
> + default:
> + dev_err_ratelimited(rm->dev, "Invalid message type (%u) received\n",
> + connection->type);
> + gh_rm_abort_connection(rm);
> + break;
> + }
> +
> + rm->active_rx_connection = NULL;
> +}
> +
> +static void gh_rm_msgq_rx_data(struct mbox_client *cl, void *mssg)
> +{
> + struct gh_rm *rm = container_of(cl, struct gh_rm, msgq_client);
> + struct gh_msgq_rx_data *rx_data = mssg;
> + size_t msg_size = rx_data->length;
> + void *msg = rx_data->data;
> + struct gh_rm_rpc_hdr *hdr;
> +
> + if (msg_size < sizeof(*hdr) || msg_size > GH_MSGQ_MAX_MSG_SIZE)
> + return;
> +
> + hdr = msg;
> + if (hdr->api != RM_RPC_API) {
> + dev_err(rm->dev, "Unknown RM RPC API version: %x\n", hdr->api);
> + return;
> + }
> +
> + switch (FIELD_GET(RM_RPC_TYPE_MASK, hdr->type)) {
> + case RM_RPC_TYPE_NOTIF:
> + gh_rm_process_notif(rm, msg, msg_size);
> + break;
> + case RM_RPC_TYPE_REPLY:
> + gh_rm_process_rply(rm, msg, msg_size);
> + break;
> + case RM_RPC_TYPE_CONTINUATION:
> + gh_rm_process_cont(rm, rm->active_rx_connection, msg, msg_size);
> + break;
> + default:
> + dev_err(rm->dev, "Invalid message type (%lu) received\n",
> + FIELD_GET(RM_RPC_TYPE_MASK, hdr->type));
> + return;
> + }
> +
> + gh_rm_try_complete_connection(rm);
> +}
> +
> +static void gh_rm_msgq_tx_done(struct mbox_client *cl, void *mssg, int r)
> +{
> + struct gh_rm *rm = container_of(cl, struct gh_rm, msgq_client);
> +
> + kmem_cache_free(rm->cache, mssg);
> + rm->last_tx_ret = r;
> +}
> +
> +static int gh_rm_send_request(struct gh_rm *rm, u32 message_id,
> + const void *req_buf, size_t req_buf_size,
> + struct gh_rm_connection *connection)
> +{
> + size_t buf_size_remaining = req_buf_size;
> + const void *req_buf_curr = req_buf;
> + struct gh_msgq_tx_data *msg;
> + struct gh_rm_rpc_hdr *hdr, hdr_template;
> + u32 cont_fragments = 0;
> + size_t payload_size;
> + void *payload;
> + int ret;
> +
> + if (req_buf_size > GH_RM_MAX_NUM_FRAGMENTS * GH_RM_MAX_MSG_SIZE) {
> + dev_warn(rm->dev, "Limit (%lu bytes) exceeded for the maximum message size: %lu\n",
> + GH_RM_MAX_NUM_FRAGMENTS * GH_RM_MAX_MSG_SIZE, req_buf_size);
> + dump_stack();
> + return -E2BIG;
> + }
> +
> + if (req_buf_size)
> + cont_fragments = (req_buf_size - 1) / GH_RM_MAX_MSG_SIZE;
> +
> + hdr_template.api = RM_RPC_API;
> + hdr_template.type = FIELD_PREP(RM_RPC_TYPE_MASK, RM_RPC_TYPE_REQUEST) |
> + FIELD_PREP(RM_RPC_FRAGMENTS_MASK, cont_fragments);
> + hdr_template.seq = cpu_to_le16(connection->reply.seq);
> + hdr_template.msg_id = cpu_to_le32(message_id);
> +
> + ret = mutex_lock_interruptible(&rm->send_lock);
> + if (ret)
> + return ret;
> +
> + do {
> + msg = kmem_cache_zalloc(rm->cache, GFP_KERNEL);
> + if (!msg) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + /* Fill header */
> + hdr = (struct gh_rm_rpc_hdr *)&msg->data[0];
> + *hdr = hdr_template;
> +
> + /* Copy payload */
> + payload = &msg->data[0] + sizeof(*hdr);
> + payload_size = min(buf_size_remaining, GH_RM_MAX_MSG_SIZE);
> + memcpy(payload, req_buf_curr, payload_size);
> + req_buf_curr += payload_size;
> + buf_size_remaining -= payload_size;
> +
> + /* Force the last fragment to immediately alert the receiver */
> + msg->push = !buf_size_remaining;
> + msg->length = sizeof(*hdr) + payload_size;
> +
> + ret = mbox_send_message(gh_msgq_chan(&rm->msgq), msg);
> + if (ret < 0) {
> + kmem_cache_free(rm->cache, msg);
> + break;
> + }
> +
> + if (rm->last_tx_ret) {
> + ret = rm->last_tx_ret;
> + break;
> + }
> +
> + hdr_template.type = FIELD_PREP(RM_RPC_TYPE_MASK, RM_RPC_TYPE_CONTINUATION) |
> + FIELD_PREP(RM_RPC_FRAGMENTS_MASK, cont_fragments);
> + } while (buf_size_remaining);
> +
> +out:
> + mutex_unlock(&rm->send_lock);
> + return ret < 0 ? ret : 0;
> +}
> +
> +/**
> + * gh_rm_call: Achieve request-response type communication with RPC
> + * @rm: Pointer to Gunyah resource manager internal data
> + * @message_id: The RM RPC message-id
> + * @req_buf: Request buffer that contains the payload
> + * @req_buf_size: Total size of the payload
> + * @resp_buf: Pointer to a response buffer
> + * @resp_buf_size: Size of the response buffer
> + *
> + * Make a request to the Resource Manager and wait for reply back. For a successful
> + * response, the function returns the payload. The size of the payload is set in
> + * resp_buf_size. The resp_buf must be freed by the caller when 0 is returned
> + * and resp_buf_size != 0.
> + *
> + * req_buf should be not NULL for req_buf_size >0. If req_buf_size == 0,
> + * req_buf *can* be NULL and no additional payload is sent.
> + *
> + * Context: Process context. Will sleep waiting for reply.
> + * Return: 0 on success. <0 if error.
> + */
> +int gh_rm_call(struct gh_rm *rm, u32 message_id, const void *req_buf, size_t req_buf_size,
> + void **resp_buf, size_t *resp_buf_size)
> +{
> + struct gh_rm_connection *connection;
> + u32 seq_id;
> + int ret;
> +
> + /* message_id 0 is reserved. req_buf_size implies req_buf is not NULL */
> + if (!rm || !message_id || (!req_buf && req_buf_size))
> + return -EINVAL;
> +
> +
> + connection = kzalloc(sizeof(*connection), GFP_KERNEL);
> + if (!connection)
> + return -ENOMEM;
> +
> + connection->type = RM_RPC_TYPE_REPLY;
> + connection->msg_id = cpu_to_le32(message_id);
> +
> + init_completion(&connection->reply.seq_done);
> +
> + /* Allocate a new seq number for this connection */
> + ret = xa_alloc_cyclic(&rm->call_xarray, &seq_id, connection, xa_limit_16b, &rm->next_seq,
> + GFP_KERNEL);
> + if (ret < 0)
> + goto free;
> + connection->reply.seq = lower_16_bits(seq_id);
> +
> + /* Send the request to the Resource Manager */
> + ret = gh_rm_send_request(rm, message_id, req_buf, req_buf_size, connection);
> + if (ret < 0)
> + goto out;
> +
> + /* Wait for response */
> + ret = wait_for_completion_interruptible(&connection->reply.seq_done);
> + if (ret)
> + goto out;
> +
> + /* Check for internal (kernel) error waiting for the response */
> + if (connection->reply.ret) {
> + ret = connection->reply.ret;
> + if (ret != -ENOMEM)
> + kfree(connection->payload);
> + goto out;
> + }
> +
> + /* Got a response, did resource manager give us an error? */
> + if (connection->reply.rm_error != GH_RM_ERROR_OK) {
> + dev_warn(rm->dev, "RM rejected message %08x. Error: %d\n", message_id,
> + connection->reply.rm_error);
> + dump_stack();
> + ret = gh_rm_remap_error(connection->reply.rm_error);
> + kfree(connection->payload);
> + goto out;
> + }
> +
> + /* Everything looks good, return the payload */
> + if (resp_buf_size)
> + *resp_buf_size = connection->size;
> + if (connection->size && resp_buf)
> + *resp_buf = connection->payload;
> + else {
> + /* kfree in case RM sent us multiple fragments but never any data in
> + * those fragments. We would've allocated memory for it, but connection->size == 0
> + */
> + kfree(connection->payload);
> + }
> +
> +out:
> + xa_erase(&rm->call_xarray, connection->reply.seq);
> +free:
> + kfree(connection);
> + return ret;
> +}
> +
> +
> +int gh_rm_notifier_register(struct gh_rm *rm, struct notifier_block *nb)
> +{
> + return blocking_notifier_chain_register(&rm->nh, nb);
> +}
> +EXPORT_SYMBOL_GPL(gh_rm_notifier_register);
> +
> +int gh_rm_notifier_unregister(struct gh_rm *rm, struct notifier_block *nb)
> +{
> + return blocking_notifier_chain_unregister(&rm->nh, nb);
> +}
> +EXPORT_SYMBOL_GPL(gh_rm_notifier_unregister);
> +
> +static int gh_msgq_platform_probe_direction(struct platform_device *pdev, bool tx,
> + struct gh_resource *ghrsc)
> +{
> + struct device_node *node = pdev->dev.of_node;
> + int ret;
> + int idx = tx ? 0 : 1;
> +
> + ghrsc->type = tx ? GH_RESOURCE_TYPE_MSGQ_TX : GH_RESOURCE_TYPE_MSGQ_RX;
> +
> + ghrsc->irq = platform_get_irq(pdev, idx);
> + if (ghrsc->irq < 0) {
> + dev_err(&pdev->dev, "Failed to get irq%d: %d\n", idx, ghrsc->irq);
> + return ghrsc->irq;
> + }
> +
> + ret = of_property_read_u64_index(node, "reg", idx, &ghrsc->capid);
> + if (ret) {
> + dev_err(&pdev->dev, "Failed to get capid%d: %d\n", idx, ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int gh_identify(void)
> +{
> + struct gh_hypercall_hyp_identify_resp gh_api;
> +
> + if (!arch_is_gh_guest())
> + return -ENODEV;
> +
> + gh_hypercall_hyp_identify(&gh_api);
> +
> + pr_info("Running under Gunyah hypervisor %llx/v%u\n",
> + FIELD_GET(GH_API_INFO_VARIANT_MASK, gh_api.api_info),
> + gh_api_version(&gh_api));
> +
> + /* We might move this out to individual drivers if there's ever an API version bump */
> + if (gh_api_version(&gh_api) != GH_API_V1) {
> + pr_info("Unsupported Gunyah version: %u\n", gh_api_version(&gh_api));
> + return -ENODEV;
> + }
> +
> + return 0;
> +}
> +
> +static int gh_rm_drv_probe(struct platform_device *pdev)
> +{
> + struct gh_msgq_tx_data *msg;
> + struct gh_rm *rm;
> + int ret;
> +
> + ret = gh_identify();
> + if (ret)
> + return ret;
> +
> + rm = devm_kzalloc(&pdev->dev, sizeof(*rm), GFP_KERNEL);
> + if (!rm)
> + return -ENOMEM;
> +
> + platform_set_drvdata(pdev, rm);
> + rm->dev = &pdev->dev;
> +
> + mutex_init(&rm->send_lock);
> + BLOCKING_INIT_NOTIFIER_HEAD(&rm->nh);
> + xa_init_flags(&rm->call_xarray, XA_FLAGS_ALLOC);
> + rm->cache = kmem_cache_create("gh_rm", struct_size(msg, data, GH_MSGQ_MAX_MSG_SIZE), 0,
> + SLAB_HWCACHE_ALIGN, NULL);
> + if (!rm->cache)
> + return -ENOMEM;
> +
> + ret = gh_msgq_platform_probe_direction(pdev, true, &rm->tx_ghrsc);
> + if (ret)
> + goto err_cache;
> +
> + ret = gh_msgq_platform_probe_direction(pdev, false, &rm->rx_ghrsc);
> + if (ret)
> + goto err_cache;
> +
> + rm->msgq_client.dev = &pdev->dev;
> + rm->msgq_client.tx_block = true;
> + rm->msgq_client.rx_callback = gh_rm_msgq_rx_data;
> + rm->msgq_client.tx_done = gh_rm_msgq_tx_done;
> +
> + return gh_msgq_init(&pdev->dev, &rm->msgq, &rm->msgq_client, &rm->tx_ghrsc, &rm->rx_ghrsc);
> +err_cache:
> + kmem_cache_destroy(rm->cache);
> + return ret;
> +}
> +
> +static int gh_rm_drv_remove(struct platform_device *pdev)
> +{
> + struct gh_rm *rm = platform_get_drvdata(pdev);
> +
> + mbox_free_channel(gh_msgq_chan(&rm->msgq));
> + gh_msgq_remove(&rm->msgq);
> + kmem_cache_destroy(rm->cache);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id gh_rm_of_match[] = {
> + { .compatible = "gunyah-resource-manager" },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, gh_rm_of_match);
> +
> +static struct platform_driver gh_rm_driver = {
> + .probe = gh_rm_drv_probe,
> + .remove = gh_rm_drv_remove,
> + .driver = {
> + .name = "gh_rsc_mgr",
> + .of_match_table = gh_rm_of_match,
> + },
> +};
> +module_platform_driver(gh_rm_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("Gunyah Resource Manager Driver");
> diff --git a/drivers/virt/gunyah/rsc_mgr.h b/drivers/virt/gunyah/rsc_mgr.h
> new file mode 100644
> index 000000000000..8309b7bf4668
> --- /dev/null
> +++ b/drivers/virt/gunyah/rsc_mgr.h
> @@ -0,0 +1,16 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
> + */
> +#ifndef __GH_RSC_MGR_PRIV_H
> +#define __GH_RSC_MGR_PRIV_H
> +
> +#include <linux/gunyah.h>
> +#include <linux/gunyah_rsc_mgr.h>
> +#include <linux/types.h>
> +
> +struct gh_rm;
> +int gh_rm_call(struct gh_rm *rsc_mgr, u32 message_id, const void *req_buf, size_t req_buf_size,
> + void **resp_buf, size_t *resp_buf_size);
> +
> +#endif
> diff --git a/include/linux/gunyah_rsc_mgr.h b/include/linux/gunyah_rsc_mgr.h
> new file mode 100644
> index 000000000000..f2a312e80af5
> --- /dev/null
> +++ b/include/linux/gunyah_rsc_mgr.h
> @@ -0,0 +1,21 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
> + */
> +
> +#ifndef _GUNYAH_RSC_MGR_H
> +#define _GUNYAH_RSC_MGR_H
> +
> +#include <linux/list.h>
> +#include <linux/notifier.h>
> +#include <linux/gunyah.h>
> +
> +#define GH_VMID_INVAL U16_MAX
> +
> +struct gh_rm;
> +int gh_rm_notifier_register(struct gh_rm *rm, struct notifier_block *nb);
> +int gh_rm_notifier_unregister(struct gh_rm *rm, struct notifier_block *nb);
> +struct device *gh_rm_get(struct gh_rm *rm);
> +void gh_rm_put(struct gh_rm *rm);
> +
> +#endif
More information about the linux-arm-kernel
mailing list