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 <[email protected]>
---
MAINTAINERS | 2 +-
drivers/virt/gunyah/Kconfig | 1 -
drivers/virt/gunyah/Makefile | 3 +
drivers/virt/gunyah/rsc_mgr.c | 616 +++++++++++++++++++++++++++++++++
drivers/virt/gunyah/rsc_mgr.h | 71 ++++
include/linux/gunyah.h | 3 +-
include/linux/gunyah_rsc_mgr.h | 18 +
7 files changed, 710 insertions(+), 4 deletions(-)
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/MAINTAINERS b/MAINTAINERS
index d02e8abe6457..7ab1462577cc 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9051,7 +9051,7 @@ F: Documentation/virt/gunyah/
F: arch/arm64/gunyah/
F: drivers/mailbox/gunyah-msgq.c
F: drivers/virt/gunyah/
-F: include/linux/gunyah.h
+F: include/linux/gunyah*.h
HABANALABS PCI DRIVER
M: Oded Gabbay <[email protected]>
diff --git a/drivers/virt/gunyah/Kconfig b/drivers/virt/gunyah/Kconfig
index 71c38845bcea..1a737694c333 100644
--- a/drivers/virt/gunyah/Kconfig
+++ b/drivers/virt/gunyah/Kconfig
@@ -4,7 +4,6 @@ config GUNYAH
tristate "Gunyah Virtualization drivers"
depends on ARM64
depends on MAILBOX
- select GUNYAH_PLATFORM_HOOKS
help
The Gunyah drivers are the helper interfaces that run in a guest VM
such as basic inter-VM IPC and signaling mechanisms, and higher level
diff --git a/drivers/virt/gunyah/Makefile b/drivers/virt/gunyah/Makefile
index 34f32110faf9..cc864ff5abbb 100644
--- a/drivers/virt/gunyah/Makefile
+++ b/drivers/virt/gunyah/Makefile
@@ -1,3 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_GUNYAH) += gunyah.o
+
+gunyah_rsc_mgr-y += rsc_mgr.o
+obj-$(CONFIG_GUNYAH) += gunyah_rsc_mgr.o
diff --git a/drivers/virt/gunyah/rsc_mgr.c b/drivers/virt/gunyah/rsc_mgr.c
new file mode 100644
index 000000000000..382f9943fd31
--- /dev/null
+++ b/drivers/virt/gunyah/rsc_mgr.c
@@ -0,0 +1,616 @@
+// 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/kthread.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 rpc_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))
+
+/**
+ * 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.
+ * @ret: Linux return code, set in case there was an error processing connection
+ * @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.
+ * @rm_error: For request/reply sequences with standard replies.
+ * @seq: Sequence ID for the main message.
+ * @seq_done: Signals caller that the RM reply has been received
+ */
+struct gh_rm_connection {
+ void *payload;
+ size_t size;
+ __le32 msg_id;
+ u8 type;
+
+ u8 num_fragments;
+ u8 fragments_received;
+
+ union {
+ struct {
+ /* only for req/reply sequence */
+ int ret;
+ u16 seq;
+ u32 rm_error; /* GH_RM_ERROR_* */
+ struct completion seq_done;
+ } reply;
+
+ struct {
+ struct work_struct work;
+ } notification;
+ };
+};
+
+struct gh_rm_notif_complete {
+ struct gh_rm_connection *conn;
+ struct work_struct work;
+};
+
+struct gh_rm {
+ struct device *dev;
+ struct gunyah_resource tx_ghrsc, rx_ghrsc;
+ struct gh_msgq msgq;
+ struct mbox_client msgq_client;
+ struct gh_rm_connection *active_rx_connection;
+ int last_tx_ret;
+
+ struct idr call_idr;
+ struct mutex call_idr_lock;
+
+ struct kmem_cache *cache;
+ struct mutex send_lock;
+
+ struct work_struct recv_work;
+};
+
+static struct gh_rm_connection *gh_rm_alloc_connection(__le32 msg_id, u8 type)
+{
+ struct gh_rm_connection *connection;
+
+ connection = kzalloc(sizeof(*connection), GFP_KERNEL);
+ if (!connection)
+ return NULL;
+
+ connection->type = type;
+ connection->msg_id = msg_id;
+
+ return connection;
+}
+
+static int gh_rm_init_connection_payload(struct gh_rm_connection *connection, void *msg,
+ size_t hdr_size, size_t msg_size)
+{
+ struct gh_rm_rpc_hdr *hdr = msg;
+ size_t max_buf_size, payload_size;
+
+ if (hdr_size > msg_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_notif_work(struct work_struct *work)
+{
+ struct gh_rm_connection *connection = container_of(work, struct gh_rm_connection,
+ notification.work);
+
+ /* No users of notifications, yet. */
+
+ kfree(connection->payload);
+ kfree(connection);
+}
+
+static struct gh_rm_connection *gh_rm_process_notif(struct gh_rm *rm, void *msg, size_t msg_size)
+{
+ struct gh_rm_rpc_hdr *hdr = msg;
+ struct gh_rm_connection *connection;
+ int ret;
+
+ connection = gh_rm_alloc_connection(hdr->msg_id, RM_RPC_TYPE_NOTIF);
+ if (!connection) {
+ dev_err(rm->dev, "Failed to alloc connection for notification, dropping.\n");
+ return NULL;
+ }
+
+ 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 buffer for notification: %d\n",
+ ret);
+ kfree(connection);
+ return NULL;
+ }
+
+ return connection;
+}
+
+static struct gh_rm_connection *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_rpc_hdr *hdr = &reply_hdr->rpc_hdr;
+ struct gh_rm_connection *connection;
+ u16 seq_id = le16_to_cpu(hdr->seq);
+
+ mutex_lock(&rm->call_idr_lock);
+ connection = idr_find(&rm->call_idr, seq_id);
+ mutex_unlock(&rm->call_idr_lock);
+
+ if (!connection) {
+ dev_err(rm->dev, "Failed to find connection for sequence %u\n", seq_id);
+ return NULL;
+ }
+ if (connection->msg_id != hdr->msg_id) {
+ dev_err(rm->dev, "Reply for sequence %u expected msg_id: %x but got %x\n",
+ seq_id, le32_to_cpu(connection->msg_id), le32_to_cpu(hdr->msg_id));
+ /*
+ * Don't complete connection and error the client, maybe
+ * resource manager will send us the expected reply sequence soon.
+ */
+ return NULL;
+ }
+
+ 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 NULL;
+ }
+
+ connection->reply.rm_error = le32_to_cpu(reply_hdr->err_code);
+ return connection;
+}
+
+static int 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);
+
+ /*
+ * 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) {
+ dev_err(rm->dev, "Appending mismatched continuation with id %d to connection with id %d\n",
+ le32_to_cpu(hdr->msg_id), le32_to_cpu(connection->msg_id));
+ return -EINVAL;
+ }
+ if (connection->num_fragments != FIELD_GET(RM_RPC_FRAGMENTS_MASK, hdr->type)) {
+ dev_err(rm->dev, "Number of fragments mismatch for message %x\n",
+ le32_to_cpu(hdr->msg_id));
+ return -EINVAL;
+ }
+
+ memcpy(connection->payload + connection->size, msg + sizeof(*hdr), payload_size);
+ connection->size += payload_size;
+ connection->fragments_received++;
+ return 0;
+}
+
+static bool gh_rm_complete_connection(struct gh_rm *rm, struct gh_rm_connection *connection)
+{
+ if (!connection)
+ return false;
+
+ if (connection->fragments_received != connection->num_fragments)
+ return false;
+
+ 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(rm->dev, "Invalid message type (%d) received\n", connection->type);
+ break;
+ }
+
+ return true;
+}
+
+static void gh_rm_abort_connection(struct gh_rm_connection *connection)
+{
+ switch (connection->type) {
+ case RM_RPC_TYPE_REPLY:
+ connection->reply.ret = -EIO;
+ complete(&connection->reply.seq_done);
+ break;
+ case RM_RPC_TYPE_NOTIF:
+ fallthrough;
+ default:
+ kfree(connection->payload);
+ kfree(connection);
+ }
+}
+
+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;
+ void *msg = rx_data->data;
+ size_t msg_size = rx_data->length;
+ struct gh_rm_rpc_hdr *hdr;
+
+ if (msg_size <= sizeof(struct gh_rm_rpc_hdr)) {
+ dev_err(rm->dev, "Incomplete message size: %ld is too small\n", 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;
+ }
+
+ if (msg_size > GH_MSGQ_MAX_MSG_SIZE) {
+ dev_err(rm->dev, "Unexpected large message received: %ld\n", msg_size);
+ return;
+ }
+
+ switch (FIELD_GET(RM_RPC_TYPE_MASK, hdr->type)) {
+ case RM_RPC_TYPE_NOTIF:
+ if (rm->active_rx_connection) {
+ /* Not possible per protocol. Do something better than BUG_ON */
+ dev_err(rm->dev, "Received start of new notification without finishing existing message series.\n");
+ gh_rm_abort_connection(rm->active_rx_connection);
+ }
+ rm->active_rx_connection = gh_rm_process_notif(rm, msg, msg_size);
+ break;
+ case RM_RPC_TYPE_REPLY:
+ if (rm->active_rx_connection) {
+ /* Not possible per protocol. Do something better than BUG_ON */
+ dev_err(rm->dev, "Received start of new reply without finishing existing message series.\n");
+ gh_rm_abort_connection(rm->active_rx_connection);
+ }
+ rm->active_rx_connection = gh_rm_process_rply(rm, msg, msg_size);
+ break;
+ case RM_RPC_TYPE_CONTINUATION:
+ if (!rm->active_rx_connection) {
+ dev_err(rm->dev, "Received a continuation message without receiving initial message\n");
+ break;
+ }
+ if (gh_rm_process_cont(rm, rm->active_rx_connection, msg, msg_size)) {
+ gh_rm_abort_connection(rm->active_rx_connection);
+ rm->active_rx_connection = NULL;
+ }
+ break;
+ default:
+ dev_err(rm->dev, "Invalid message type (%lu) received\n",
+ FIELD_GET(RM_RPC_TYPE_MASK, hdr->type));
+ return;
+ }
+
+ if (gh_rm_complete_connection(rm, rm->active_rx_connection))
+ rm->active_rx_connection = NULL;
+}
+
+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_buff, size_t req_buff_size,
+ struct gh_rm_connection *connection)
+{
+ size_t buff_size_remaining = req_buff_size;
+ u32 cont_fragments = 0;
+ struct gh_rm_rpc_hdr *hdr;
+ struct gh_msgq_tx_data *msg;
+ u8 msg_type = FIELD_PREP(RM_RPC_TYPE_MASK, RM_RPC_TYPE_REQUEST);
+ void *payload;
+ size_t payload_size;
+ const void *req_buff_curr = req_buff;
+ int ret;
+
+ if (req_buff_size)
+ cont_fragments = (req_buff_size - 1) / GH_RM_MAX_MSG_SIZE;
+
+ if (req_buff_size > GH_RM_MAX_NUM_FRAGMENTS * GH_RM_MAX_MSG_SIZE) {
+ pr_warn("Limit exceeded for the number of fragments: %u\n", cont_fragments);
+ dump_stack();
+ return -E2BIG;
+ }
+
+ ret = mutex_lock_interruptible(&rm->send_lock);
+ if (ret)
+ return ret;
+
+ /* Consider also the 'request' packet for the loop count */
+ 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;
+ hdr->api = RM_RPC_API;
+ hdr->type = msg_type | FIELD_PREP(RM_RPC_FRAGMENTS_MASK, cont_fragments);
+ hdr->seq = cpu_to_le16(connection->reply.seq);
+ hdr->msg_id = cpu_to_le32(message_id);
+
+ /* Copy payload */
+ payload = hdr + 1;
+ payload_size = min(buff_size_remaining, GH_RM_MAX_MSG_SIZE);
+ memcpy(payload, req_buff_curr, payload_size);
+ req_buff_curr += payload_size;
+ buff_size_remaining -= payload_size;
+
+ /* Force the last fragment to immediately alert the receiver */
+ msg->push = !buff_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;
+ }
+
+ msg_type = FIELD_PREP(RM_RPC_TYPE_MASK, RM_RPC_TYPE_CONTINUATION);
+ } while (buff_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_buff: Request buffer that contains the payload
+ * @req_buff_size: Total size of the payload
+ * @resp_buf: Pointer to a response buffer
+ * @resp_buff_size: Size of the response buffer
+ *
+ * Make a request to the RM-VM and wait for reply back. For a successful
+ * response, the function returns the payload. The size of the payload is set in
+ * resp_buff_size. The resp_buf should be freed by the caller.
+ *
+ * req_buff should be not NULL for req_buff_size >0. If req_buff_size == 0,
+ * req_buff *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, void *req_buff, size_t req_buff_size,
+ void **resp_buf, size_t *resp_buff_size)
+{
+ struct gh_rm_connection *connection;
+ int ret;
+
+ /* message_id 0 is reserved. req_buff_size implies req_buf is not NULL */
+ if (!message_id || (!req_buff && req_buff_size))
+ return -EINVAL;
+
+ if (!rm)
+ return -EPROBE_DEFER;
+
+ connection = gh_rm_alloc_connection(cpu_to_le32(message_id), RM_RPC_TYPE_REPLY);
+ if (!connection)
+ return -ENOMEM;
+
+ init_completion(&connection->reply.seq_done);
+
+ /* Allocate a new seq number for this connection */
+ mutex_lock(&rm->call_idr_lock);
+ ret = idr_alloc_cyclic(&rm->call_idr, connection, 0, U16_MAX,
+ GFP_KERNEL);
+ mutex_unlock(&rm->call_idr_lock);
+ if (ret < 0)
+ goto out;
+ connection->reply.seq = ret;
+
+ /* Send the request to the Resource Manager */
+ ret = gh_rm_send_request(rm, message_id, req_buff, req_buff_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;
+ kfree(connection->payload);
+ goto out;
+ }
+
+ /* Got a response, did resource manager give us an error? */
+ if (connection->reply.rm_error) {
+ pr_warn("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 */
+ *resp_buff_size = connection->size;
+ if (connection->size)
+ *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:
+ mutex_lock(&rm->call_idr_lock);
+ idr_remove(&rm->call_idr, connection->reply.seq);
+ mutex_unlock(&rm->call_idr_lock);
+ kfree(connection);
+ return ret;
+}
+
+static int gh_msgq_platform_probe_direction(struct platform_device *pdev,
+ bool tx, int idx, struct gunyah_resource *ghrsc)
+{
+ int ret;
+ struct device_node *node = pdev->dev.of_node;
+
+ ghrsc->type = tx ? GUNYAH_RESOURCE_TYPE_MSGQ_TX : GUNYAH_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_rm_drv_probe(struct platform_device *pdev)
+{
+ struct gh_rm *rm;
+ int 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->call_idr_lock);
+ idr_init(&rm->call_idr);
+ 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;
+ mutex_init(&rm->send_lock);
+
+ ret = gh_msgq_platform_probe_direction(pdev, true, 0, &rm->tx_ghrsc);
+ if (ret)
+ goto err_cache;
+
+ ret = gh_msgq_platform_probe_direction(pdev, false, 1, &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);
+}
+
+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..824749e63a54
--- /dev/null
+++ b/drivers/virt/gunyah/rsc_mgr.h
@@ -0,0 +1,71 @@
+/* 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>
+
+/* RM Error codes */
+#define GH_RM_ERROR_OK 0x0
+#define GH_RM_ERROR_UNIMPLEMENTED 0xFFFFFFFF
+#define GH_RM_ERROR_NOMEM 0x1
+#define GH_RM_ERROR_NORESOURCE 0x2
+#define GH_RM_ERROR_DENIED 0x3
+#define GH_RM_ERROR_INVALID 0x4
+#define GH_RM_ERROR_BUSY 0x5
+#define GH_RM_ERROR_ARGUMENT_INVALID 0x6
+#define GH_RM_ERROR_HANDLE_INVALID 0x7
+#define GH_RM_ERROR_VALIDATE_FAILED 0x8
+#define GH_RM_ERROR_MAP_FAILED 0x9
+#define GH_RM_ERROR_MEM_INVALID 0xA
+#define GH_RM_ERROR_MEM_INUSE 0xB
+#define GH_RM_ERROR_MEM_RELEASED 0xC
+#define GH_RM_ERROR_VMID_INVALID 0xD
+#define GH_RM_ERROR_LOOKUP_FAILED 0xE
+#define GH_RM_ERROR_IRQ_INVALID 0xF
+#define GH_RM_ERROR_IRQ_INUSE 0x10
+#define GH_RM_ERROR_IRQ_RELEASED 0x11
+
+static inline int gh_rm_remap_error(int 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;
+ }
+}
+
+struct gh_rm;
+int gh_rm_call(struct gh_rm *rsc_mgr, u32 message_id, void *req_buff, size_t req_buff_size,
+ void **resp_buf, size_t *resp_buff_size);
+
+#endif
diff --git a/include/linux/gunyah.h b/include/linux/gunyah.h
index 5d6fc9f88718..91d2c9f5b2f0 100644
--- a/include/linux/gunyah.h
+++ b/include/linux/gunyah.h
@@ -119,12 +119,11 @@ static inline int gh_remap_error(int gh_error)
return -EACCES;
case GH_ERROR_BUSY:
case GH_ERROR_IDLE:
- return -EBUSY;
case GH_ERROR_IRQ_BOUND:
case GH_ERROR_IRQ_UNBOUND:
case GH_ERROR_MSGQUEUE_FULL:
case GH_ERROR_MSGQUEUE_EMPTY:
- return -EPERM;
+ return -EBUSY;
default:
return -EINVAL;
}
diff --git a/include/linux/gunyah_rsc_mgr.h b/include/linux/gunyah_rsc_mgr.h
new file mode 100644
index 000000000000..959787ad0a3d
--- /dev/null
+++ b/include/linux/gunyah_rsc_mgr.h
@@ -0,0 +1,18 @@
+/* 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
+
+/* Gunyah recognizes VMID0 as an alias to the current VM's ID */
+#define GH_VMID_SELF 0
+
+#endif
--
2.39.0
On 20/01/2023 22:46, 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
I dont see this notifier related change in this patch or in this series.
>
> Specific API calls that resource manager supports will be implemented in
> subsequent patches.
>
> Signed-off-by: Elliot Berman <[email protected]>
> ---
> MAINTAINERS | 2 +-
> drivers/virt/gunyah/Kconfig | 1 -
> drivers/virt/gunyah/Makefile | 3 +
> drivers/virt/gunyah/rsc_mgr.c | 616 +++++++++++++++++++++++++++++++++
> drivers/virt/gunyah/rsc_mgr.h | 71 ++++
> include/linux/gunyah.h | 3 +-
> include/linux/gunyah_rsc_mgr.h | 18 +
> 7 files changed, 710 insertions(+), 4 deletions(-)
> 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/MAINTAINERS b/MAINTAINERS
> index d02e8abe6457..7ab1462577cc 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -9051,7 +9051,7 @@ F: Documentation/virt/gunyah/
> F: arch/arm64/gunyah/
> F: drivers/mailbox/gunyah-msgq.c
> F: drivers/virt/gunyah/
> -F: include/linux/gunyah.h
> +F: include/linux/gunyah*.h
>
It might be good idea to add a dedicated patch for updating MAINTAINERS
file at the end of series.
> HABANALABS PCI DRIVER
> M: Oded Gabbay <[email protected]>
> diff --git a/drivers/virt/gunyah/Kconfig b/drivers/virt/gunyah/Kconfig
> index 71c38845bcea..1a737694c333 100644
> --- a/drivers/virt/gunyah/Kconfig
> +++ b/drivers/virt/gunyah/Kconfig
> @@ -4,7 +4,6 @@ config GUNYAH
> tristate "Gunyah Virtualization drivers"
> depends on ARM64
> depends on MAILBOX
> - select GUNYAH_PLATFORM_HOOKS
> help
> The Gunyah drivers are the helper interfaces that run in a guest VM
> such as basic inter-VM IPC and signaling mechanisms, and higher level
> diff --git a/drivers/virt/gunyah/Makefile b/drivers/virt/gunyah/Makefile
> index 34f32110faf9..cc864ff5abbb 100644
> --- a/drivers/virt/gunyah/Makefile
> +++ b/drivers/virt/gunyah/Makefile
> @@ -1,3 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0
>
> obj-$(CONFIG_GUNYAH) += gunyah.o
> +
> +gunyah_rsc_mgr-y += rsc_mgr.o
> +obj-$(CONFIG_GUNYAH) += gunyah_rsc_mgr.o
> diff --git a/drivers/virt/gunyah/rsc_mgr.c b/drivers/virt/gunyah/rsc_mgr.c
> new file mode 100644
> index 000000000000..382f9943fd31
> --- /dev/null
> +++ b/drivers/virt/gunyah/rsc_mgr.c
> @@ -0,0 +1,616 @@
> +// 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/kthread.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;
> +
#define GH_RM_RPC_HDR_SZ sizeof(struct gh_rm_rpc_hdr)
You could use this in most of the places where sizeof is being called.
> +struct gh_rm_rpc_reply_hdr {
> + struct gh_rm_rpc_hdr rpc_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))
> +
> +/**
> + * 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.
> + * @ret: Linux return code, set in case there was an error processing connection
> + * @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.
> + * @rm_error: For request/reply sequences with standard replies.
> + * @seq: Sequence ID for the main message.
> + * @seq_done: Signals caller that the RM reply has been received
> + */
> +struct gh_rm_connection {
> + void *payload;
> + size_t size;
> + __le32 msg_id;
> + u8 type;
> +
> + u8 num_fragments;
> + u8 fragments_received;
> +
> + union {
> + struct {
> + /* only for req/reply sequence */
> + int ret;
> + u16 seq;
> + u32 rm_error; /* GH_RM_ERROR_* */
> + struct completion seq_done;
> + } reply;
> +
> + struct {
> + struct work_struct work;
> + } notification;
> + };
> +};
> +
> +struct gh_rm_notif_complete {
> + struct gh_rm_connection *conn;
> + struct work_struct work;
> +};
No users for this.
> +
> +struct gh_rm {
> + struct device *dev;
> + struct gunyah_resource tx_ghrsc, rx_ghrsc;
> + struct gh_msgq msgq;
> + struct mbox_client msgq_client;
> + struct gh_rm_connection *active_rx_connection;
> + int last_tx_ret;
> +
> + struct idr call_idr;
> + struct mutex call_idr_lock;
> +
> + struct kmem_cache *cache;
> + struct mutex send_lock;
> +
> + struct work_struct recv_work;
?? No users
> +};
> +
> +static struct gh_rm_connection *gh_rm_alloc_connection(__le32 msg_id, u8 type)
> +{
> + struct gh_rm_connection *connection;
> +
> + connection = kzalloc(sizeof(*connection), GFP_KERNEL);
> + if (!connection)
> + return NULL;
Error code is now lost here, we should probgate the error to the caller.
return ERR_PTR(-ENOMEM);
and let the caller check return value by IS_ERR()
> +
> + connection->type = type;
> + connection->msg_id = msg_id;
> +
> + return connection;
> +}
> +
> +static int gh_rm_init_connection_payload(struct gh_rm_connection *connection, void *msg,
> + size_t hdr_size, size_t msg_size)
> +{
> + struct gh_rm_rpc_hdr *hdr = msg;
> + size_t max_buf_size, payload_size;
> +
> + if (hdr_size > msg_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_notif_work(struct work_struct *work)
> +{
> + struct gh_rm_connection *connection = container_of(work, struct gh_rm_connection,
> + notification.work);
> +
> + /* No users of notifications, yet. */
> +
> + kfree(connection->payload);
> + kfree(connection);
> +}
> +
> +static struct gh_rm_connection *gh_rm_process_notif(struct gh_rm *rm, void *msg, size_t msg_size)
> +{
> + struct gh_rm_rpc_hdr *hdr = msg;
> + struct gh_rm_connection *connection;
> + int ret;
> +
> + connection = gh_rm_alloc_connection(hdr->msg_id, RM_RPC_TYPE_NOTIF);
> + if (!connection) {
> + dev_err(rm->dev, "Failed to alloc connection for notification, dropping.\n");
> + return NULL;
> + }
> +
> + 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 buffer for notification: %d\n",
> + ret);
> + kfree(connection);
> + return NULL;
> + }
> +
> + return connection;
> +}
> +
> +static struct gh_rm_connection *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_rpc_hdr *hdr = &reply_hdr->rpc_hdr;
> + struct gh_rm_connection *connection;
> + u16 seq_id = le16_to_cpu(hdr->seq);
> +
> + mutex_lock(&rm->call_idr_lock);
> + connection = idr_find(&rm->call_idr, seq_id);
> + mutex_unlock(&rm->call_idr_lock);
> +
> + if (!connection) {
> + dev_err(rm->dev, "Failed to find connection for sequence %u\n", seq_id);
> + return NULL;
> + }
> + if (connection->msg_id != hdr->msg_id) {
Are we saying that there will be multiple msg_ids for a single
connection seq_id?
> + dev_err(rm->dev, "Reply for sequence %u expected msg_id: %x but got %x\n",
> + seq_id, le32_to_cpu(connection->msg_id), le32_to_cpu(hdr->msg_id));
> + /*
> + * Don't complete connection and error the client, maybe
> + * resource manager will send us the expected reply sequence soon.
> + */
> + return NULL;
> + }
> +
> + 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 NULL;
> + }
> +
> + connection->reply.rm_error = le32_to_cpu(reply_hdr->err_code);
> + return connection;
> +}
> +
> +static int 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);
I think its worth defining GH_RM_RPC_HDR_SZ, looks like its used in many
places.
> +
> + /*
> + * 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) {
> + dev_err(rm->dev, "Appending mismatched continuation with id %d to connection with id %d\n",
> + le32_to_cpu(hdr->msg_id), le32_to_cpu(connection->msg_id));
> + return -EINVAL;
> + }
> + if (connection->num_fragments != FIELD_GET(RM_RPC_FRAGMENTS_MASK, hdr->type)) {
> + dev_err(rm->dev, "Number of fragments mismatch for message %x\n",
> + le32_to_cpu(hdr->msg_id));
> + return -EINVAL;
> + }
> +
> + memcpy(connection->payload + connection->size, msg + sizeof(*hdr), payload_size);
> + connection->size += payload_size;
> + connection->fragments_received++;
> + return 0;
> +}
> +
> +static bool gh_rm_complete_connection(struct gh_rm *rm, struct gh_rm_connection *connection)
> +{
> + if (!connection)
> + return false;
> +
> + if (connection->fragments_received != connection->num_fragments)
> + return false;
> +
> + switch (connection->type) {
> + case RM_RPC_TYPE_REPLY:
> + complete(&connection->reply.seq_done);
> + break;
> + case RM_RPC_TYPE_NOTIF:
> + schedule_work(&connection->notification.work);
If there are no real users for this why not just
kfree(connection->payload);
kfree(connection);
> + break;
> + default:
> + dev_err(rm->dev, "Invalid message type (%d) received\n", connection->type);
will we have this case at all? if yes then are we leaking connection object?
> + break;
> + }
> +
> + return true;
> +}
> +
> +static void gh_rm_abort_connection(struct gh_rm_connection *connection)
> +{
> + switch (connection->type) {
> + case RM_RPC_TYPE_REPLY:
> + connection->reply.ret = -EIO;
> + complete(&connection->reply.seq_done);
> + break;
> + case RM_RPC_TYPE_NOTIF:
> + fallthrough;
> + default:
> + kfree(connection->payload);
> + kfree(connection);
> + }
> +}
> +
> +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;
> + void *msg = rx_data->data;
> + size_t msg_size = rx_data->length;
> + struct gh_rm_rpc_hdr *hdr;
> +
> + if (msg_size <= sizeof(struct gh_rm_rpc_hdr)) {
> + dev_err(rm->dev, "Incomplete message size: %ld is too small\n", 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;
> + }
> +
> + if (msg_size > GH_MSGQ_MAX_MSG_SIZE) {
> + dev_err(rm->dev, "Unexpected large message received: %ld\n", msg_size);
> + return;
> + }
> +
> + switch (FIELD_GET(RM_RPC_TYPE_MASK, hdr->type)) {
> + case RM_RPC_TYPE_NOTIF:
> + if (rm->active_rx_connection) {
> + /* Not possible per protocol. Do something better than BUG_ON */
> + dev_err(rm->dev, "Received start of new notification without finishing existing message series.\n");
> + gh_rm_abort_connection(rm->active_rx_connection);
> + }
> + rm->active_rx_connection = gh_rm_process_notif(rm, msg, msg_size);
> + break;
> + case RM_RPC_TYPE_REPLY:
> + if (rm->active_rx_connection) {
> + /* Not possible per protocol. Do something better than BUG_ON */
> + dev_err(rm->dev, "Received start of new reply without finishing existing message series.\n");
> + gh_rm_abort_connection(rm->active_rx_connection);
> + }
> + rm->active_rx_connection = gh_rm_process_rply(rm, msg, msg_size);
> + break;
> + case RM_RPC_TYPE_CONTINUATION:
> + if (!rm->active_rx_connection) {
> + dev_err(rm->dev, "Received a continuation message without receiving initial message\n");
> + break;
> + }
> + if (gh_rm_process_cont(rm, rm->active_rx_connection, msg, msg_size)) {
> + gh_rm_abort_connection(rm->active_rx_connection);
> + rm->active_rx_connection = NULL;
> + }
> + break;
> + default:
> + dev_err(rm->dev, "Invalid message type (%lu) received\n",
> + FIELD_GET(RM_RPC_TYPE_MASK, hdr->type));
> + return;
> + }
> +
> + if (gh_rm_complete_connection(rm, rm->active_rx_connection))
> + rm->active_rx_connection = NULL;
> +}
> +
> +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_buff, size_t req_buff_size,
> + struct gh_rm_connection *connection)
> +{
> + size_t buff_size_remaining = req_buff_size;
> + u32 cont_fragments = 0;
> + struct gh_rm_rpc_hdr *hdr;
> + struct gh_msgq_tx_data *msg;
> + u8 msg_type = FIELD_PREP(RM_RPC_TYPE_MASK, RM_RPC_TYPE_REQUEST);
> + void *payload;
> + size_t payload_size;
> + const void *req_buff_curr = req_buff;
> + int ret;
> +
> + if (req_buff_size)
> + cont_fragments = (req_buff_size - 1) / GH_RM_MAX_MSG_SIZE;
> +
> + if (req_buff_size > GH_RM_MAX_NUM_FRAGMENTS * GH_RM_MAX_MSG_SIZE) {
> + pr_warn("Limit exceeded for the number of fragments: %u\n", cont_fragments);
> + dump_stack();
> + return -E2BIG;
> + }
> +
> + ret = mutex_lock_interruptible(&rm->send_lock);
> + if (ret)
> + return ret;
> +
> + /* Consider also the 'request' packet for the loop count */
> + 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;
> + hdr->api = RM_RPC_API;
> + hdr->type = msg_type | FIELD_PREP(RM_RPC_FRAGMENTS_MASK, cont_fragments);
> + hdr->seq = cpu_to_le16(connection->reply.seq);
> + hdr->msg_id = cpu_to_le32(message_id);
> +
> + /* Copy payload */
> + payload = hdr + 1;
> + payload_size = min(buff_size_remaining, GH_RM_MAX_MSG_SIZE);
> + memcpy(payload, req_buff_curr, payload_size);
> + req_buff_curr += payload_size;
> + buff_size_remaining -= payload_size;
> +
> + /* Force the last fragment to immediately alert the receiver */
> + msg->push = !buff_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;
> + }
> +
> + msg_type = FIELD_PREP(RM_RPC_TYPE_MASK, RM_RPC_TYPE_CONTINUATION);
> + } while (buff_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_buff: Request buffer that contains the payload
> + * @req_buff_size: Total size of the payload
> + * @resp_buf: Pointer to a response buffer
> + * @resp_buff_size: Size of the response buffer
> + *
> + * Make a request to the RM-VM and wait for reply back. For a successful
> + * response, the function returns the payload. The size of the payload is set in
> + * resp_buff_size. The resp_buf should be freed by the caller.
> + *
> + * req_buff should be not NULL for req_buff_size >0. If req_buff_size == 0,
> + * req_buff *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, void *req_buff, size_t req_buff_size,
> + void **resp_buf, size_t *resp_buff_size)
Should we export this function or is this a static function?
> +{
> + struct gh_rm_connection *connection;
> + int ret;
> +
> + /* message_id 0 is reserved. req_buff_size implies req_buf is not NULL */
> + if (!message_id || (!req_buff && req_buff_size))
> + return -EINVAL;
> +
> + if (!rm)
> + return -EPROBE_DEFER;
Not sure what is the intent here, the caller should already know if he
is sending NULL ptr.
> +
> + connection = gh_rm_alloc_connection(cpu_to_le32(message_id), RM_RPC_TYPE_REPLY);
> + if (!connection)
> + return -ENOMEM;
> +
> + init_completion(&connection->reply.seq_done);
> +
> + /* Allocate a new seq number for this connection */
> + mutex_lock(&rm->call_idr_lock);
> + ret = idr_alloc_cyclic(&rm->call_idr, connection, 0, U16_MAX,
> + GFP_KERNEL);
> + mutex_unlock(&rm->call_idr_lock);
> + if (ret < 0)
> + goto out;
> + connection->reply.seq = ret;
> +
> + /* Send the request to the Resource Manager */
> + ret = gh_rm_send_request(rm, message_id, req_buff, req_buff_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) {
You should probably check the ret to see if allocation of payload has
failed before calling kfree.
> + ret = connection->reply.ret;
> + kfree(connection->payload);
Atleast by the looks of gh_rm_init_connection_payload you should not
even call kfree in error cases.
> + goto out;
> + }
> +
> + /* Got a response, did resource manager give us an error? */
> + if (connection->reply.rm_error) {
> + pr_warn("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 */
> + *resp_buff_size = connection->size;
> + if (connection->size)
> + *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:
> + mutex_lock(&rm->call_idr_lock);
> + idr_remove(&rm->call_idr, connection->reply.seq);
> + mutex_unlock(&rm->call_idr_lock);
> + kfree(connection);
> + return ret;
> +}
> +
> +static int gh_msgq_platform_probe_direction(struct platform_device *pdev,
> + bool tx, int idx, struct gunyah_resource *ghrsc)
> +{
> + int ret;
> + struct device_node *node = pdev->dev.of_node;
> +
> + ghrsc->type = tx ? GUNYAH_RESOURCE_TYPE_MSGQ_TX : GUNYAH_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_rm_drv_probe(struct platform_device *pdev)
> +{
> + struct gh_rm *rm;
> + int 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->call_idr_lock);
> + idr_init(&rm->call_idr);
> + 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;
> + mutex_init(&rm->send_lock);
> +
> + ret = gh_msgq_platform_probe_direction(pdev, true, 0, &rm->tx_ghrsc);
> + if (ret)
> + goto err_cache;
this lable does not exist in the patch.
> +
> + ret = gh_msgq_platform_probe_direction(pdev, false, 1, &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);
> +}
> +
> +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");
--srini
On 2/2/23 5:53 AM, Srinivas Kandagatla wrote:
>>
>> +struct gh_rm_rpc_hdr {
>> + u8 api;
>> + u8 type;
>> + __le16 seq;
>> + __le32 msg_id;
>> +} __packed;
>> +
> #define GH_RM_RPC_HDR_SZ sizeof(struct gh_rm_rpc_hdr)
>
> You could use this in most of the places where sizeof is being called.
I'll repeat my point here. I see no value in hiding
the size of the structure behind a defined symbol.
Use sizeof(*pointer) (if possible) or sizeof(struct foo) in
the code; it makes it very clear that it's not something
other than a simple object/structure size.
-Alex