Messages in this thread Patch in this message | | | Date | Thu, 13 Oct 2022 00:47:25 +0300 | Subject | Re: [PATCH v5 09/13] mailbox: Add Gunyah message queue mailbox | From | Dmitry Baryshkov <> |
| |
On 11/10/2022 03:08, Elliot Berman wrote: > Gunyah message queues are a unidirectional inter-VM pipe for messages up > to 1024 bytes. This driver supports pairing a receiver message queue and > a transmitter message queue to expose a single mailbox channel. > > Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> > --- > MAINTAINERS | 2 + > drivers/mailbox/Kconfig | 10 ++ > drivers/mailbox/Makefile | 2 + > drivers/mailbox/gunyah-msgq.c | 254 ++++++++++++++++++++++++++++++++++ > drivers/virt/gunyah/Kconfig | 2 + > include/linux/gunyah.h | 67 +++++++++ > 6 files changed, 337 insertions(+) > create mode 100644 drivers/mailbox/gunyah-msgq.c > create mode 100644 include/linux/gunyah.h > > diff --git a/MAINTAINERS b/MAINTAINERS > index c5458aeec023..599804836d05 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -8888,8 +8888,10 @@ F: Documentation/ABI/testing/sysfs-hypervisor-gunyah > F: Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml > F: Documentation/virt/gunyah/ > F: arch/arm64/gunyah/ > +F: drivers/mailbox/gunyah-msgq.c > F: drivers/virt/gunyah/ > F: include/asm-generic/gunyah.h > +F: include/linux/gunyah.h > > HABANALABS PCI DRIVER > M: Oded Gabbay <ogabbay@kernel.org> > diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig > index 05d6fae800e3..baf9451c5f04 100644 > --- a/drivers/mailbox/Kconfig > +++ b/drivers/mailbox/Kconfig > @@ -41,6 +41,16 @@ config IMX_MBOX > help > Mailbox implementation for i.MX Messaging Unit (MU). > > +config GUNYAH_MESSAGE_QUEUES > + tristate "Gunyah Message Queue Mailbox" > + depends on GUNYAH > + help > + Mailbox implementation for Gunyah Message Queues. Gunyah message queues > + are an IPC mechanism to pass short messages between virtual machines > + running under the Gunyah hypervisor. > + > + Say Y here if you run Linux as a Gunyah virtual machine. > + > config PLATFORM_MHU > tristate "Platform MHU Mailbox" > depends on OF > diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile > index fc9376117111..5f929bb55e9a 100644 > --- a/drivers/mailbox/Makefile > +++ b/drivers/mailbox/Makefile > @@ -55,6 +55,8 @@ obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o > > obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o > > +obj-$(CONFIG_GUNYAH) += gunyah-msgq.o > + > obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o > > obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o > diff --git a/drivers/mailbox/gunyah-msgq.c b/drivers/mailbox/gunyah-msgq.c > new file mode 100644 > index 000000000000..f0cd96920c64 > --- /dev/null > +++ b/drivers/mailbox/gunyah-msgq.c > @@ -0,0 +1,254 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved. > + */ > + > +#include <linux/mailbox_controller.h> > +#include <linux/module.h> > +#include <linux/interrupt.h> > +#include <linux/gunyah.h> > +#include <linux/printk.h> > +#include <linux/init.h> > +#include <linux/slab.h> > +#include <linux/wait.h> > + > +#define mbox_chan_to_msgq(chan) (container_of(chan->mbox, struct gunyah_msgq, mbox)) > + > +static inline bool gh_msgq_has_tx(struct gunyah_msgq *msgq) > +{ > + return msgq->tx_ghrsc.type == GUNYAH_RESOURCE_TYPE_MSGQ_TX; > +} > + > +static inline bool gh_msgq_has_rx(struct gunyah_msgq *msgq) > +{ > + return msgq->rx_ghrsc.type == GUNYAH_RESOURCE_TYPE_MSGQ_RX; > +} > + > +static ssize_t __gh_msgq_recv(struct gunyah_msgq *msgq, void *buff, size_t size, bool *ready) > +{ > + unsigned long gh_err; > + size_t recv_size; > + ssize_t ret; > + > + gh_err = gh_hypercall_msgq_recv(msgq->rx_ghrsc.capid, (uintptr_t)buff, size, > + &recv_size, ready); > + switch (gh_err) { > + case GH_ERROR_OK: > + ret = recv_size; > + break; > + case GH_ERROR_MSGQUEUE_EMPTY: > + ret = -EAGAIN; > + *ready = false; > + break; > + default: > + ret = gh_remap_error(gh_err); > + break; > + } > + > + return ret; > +} > + > +static irqreturn_t gh_msgq_rx_irq_handler(int irq, void *data) > +{ > + struct gunyah_msgq *msgq = data; > + struct gunyah_msgq_rx_data rx_data; > + ssize_t ret; > + bool more; > + > + do { > + ret = __gh_msgq_recv(msgq, &rx_data.data, sizeof(rx_data.data), &more);
Inline the call please.
> + > + if (ret >= 0) { > + rx_data.length = ret; > + mbox_chan_received_data(gunyah_msgq_chan(msgq), &rx_data); > + } else if (ret != -EAGAIN) > + pr_warn("Failed to receive data from msgq for %s: %ld\n", > + msgq->mbox.dev ? dev_name(msgq->mbox.dev) : "", ret); > + } while (ret >= 0); > + > + return IRQ_HANDLED; > +} > + > +static irqreturn_t gh_msgq_tx_irq_handler(int irq, void *data) > +{ > + struct gunyah_msgq *msgq = data; > + > + mbox_chan_txdone(gunyah_msgq_chan(msgq), 0); > + > + return IRQ_HANDLED; > +} > + > +static void gh_msgq_txdone_tasklet(unsigned long data) > +{ > + struct gunyah_msgq *msgq = (struct gunyah_msgq *)data; > + > + mbox_chan_txdone(gunyah_msgq_chan(msgq), msgq->last_status);
I don't quite get this. Why do you need both an IRQ and a tasklet?
> +} > + > +static int __gh_msgq_send(struct gunyah_msgq *msgq, void *buff, size_t size, u64 tx_flags) > +{ > + unsigned long gh_err; > + ssize_t ret; > + bool ready; > + > + gh_err = gh_hypercall_msgq_send(msgq->tx_ghrsc.capid, size, (uintptr_t)buff, tx_flags, > + &ready); > + switch (gh_err) { > + case GH_ERROR_OK: > + ret = !ready; > + break; > + case GH_ERROR_MSGQUEUE_FULL: > + ret = -EAGAIN; > + break; > + default: > + /* Not sure how to propagate these out to client. If we get here, nobody is going > + * to trigger a retry > + */ > + ret = gh_remap_error(gh_err); > + break; > + } > + > + return ret; > +} > + > +static int gh_msgq_send_data(struct mbox_chan *chan, void *data) > +{ > + struct gunyah_msgq *msgq = mbox_chan_to_msgq(chan); > + struct gunyah_msgq_tx_data *msgq_data = data; > + u64 tx_flags = 0; > + int ret; > + > + if (msgq_data->push) > + tx_flags |= GH_HYPERCALL_MSGQ_TX_FLAGS_PUSH; > + > + ret = __gh_msgq_send(msgq, msgq_data->data, msgq_data->length, tx_flags);
Inline the call.
> + > + /** > + * EAGAIN: message didn't send. > + * ret = 1: message sent, but now the message queue is full and we can't send any more msgs. > + * Either way, don't report that this message is done. > + */ > + if (ret == -EAGAIN || ret == 1) > + return ret;
'1' doesn't seem to be a valid return code for _send_data.
Also it would be logical to return any error here, not just -EAGAIN.
> + > + /** > + * Mailbox framework requires that tx done happens asynchronously to sending the message > + * IOW, a notification that the message was sent happens after sending the message. > + * To work around this, defer the txdone to a tasklet. > + */ > + msgq->last_status = ret; > + tasklet_schedule(&msgq->txdone_tasklet); > + > + return 0; > +} > + > +struct mbox_chan_ops gunyah_msgq_ops = { > + .send_data = gh_msgq_send_data, > +}; > + > +/** > + * gunyah_msgq_init() - Initialize a Gunyah message queue with an mbox_client > + * @parent: optional, device parent used for the mailbox controller > + * @msgq: Pointer to the gunyah_msgq to initialize > + * @cl: A mailbox client to bind to the mailbox channel that the message queue creates > + * @tx_ghrsc: optional, the transmission side of the message queue > + * @rx_ghrsc: optional, the receiving side of the message queue > + * > + * At least one of tx_ghrsc and rx_ghrsc should be not NULL. Most message queue use cases come with > + * a pair of message queues to facilitiate bidirectional communication. When tx_ghrsc is set, > + * the client can send messages with mbox_send_message(gunyah_msgq_chan(msgq), msg). When rx_ghrsc > + * is set, the mbox_client should register an .rx_callback() and the message queue driver will > + * push all available messages upon receiving the RX ready interrupt. The messages should be > + * consumed or copied by the client right away as the gunyah_msgq_rx_data will be replaced/destroyed > + * after the callback. > + * > + * Returns - 0 on success, negative otherwise > + */ > +int gunyah_msgq_init(struct device *parent, struct gunyah_msgq *msgq, struct mbox_client *cl, > + struct gunyah_resource *tx_ghrsc, struct gunyah_resource *rx_ghrsc)
Are the message queues allocated/created dynamically or statically? If the later is true, please use devm_request(_threaded)_irq and devm_kzalloc.
> +{ > + int ret; > + > + /* Must have at least a tx_ghrsc or rx_ghrsc and that they are the right device types */ > + if ((!tx_ghrsc && !rx_ghrsc) || > + (tx_ghrsc && tx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_TX) || > + (rx_ghrsc && rx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_RX)) > + return -EINVAL; > + > + msgq->tx_ghrsc = *tx_ghrsc; > + msgq->rx_ghrsc = *rx_ghrsc;
Why? You can just turn msg->tx_ghrsc/rx_ghrsc into pointers and just assign them here.
> + > + msgq->mbox.dev = parent; > + msgq->mbox.ops = &gunyah_msgq_ops; > + msgq->mbox.chans = kcalloc(1, sizeof(*msgq->mbox.chans), GFP_KERNEL);
kzalloc?
> + msgq->mbox.num_chans = 1; > + msgq->mbox.txdone_irq = true; > + > + if (gh_msgq_has_tx(msgq)) { > + ret = request_irq(msgq->tx_ghrsc.irq, gh_msgq_tx_irq_handler, 0, "gh_msgq_tx", > + msgq); > + if (ret) > + goto err_chans; > + } > + > + if (gh_msgq_has_rx(msgq)) { > + ret = request_threaded_irq(msgq->rx_ghrsc.irq, NULL, gh_msgq_rx_irq_handler, > + IRQF_ONESHOT, "gh_msgq_rx", msgq); > + if (ret) > + goto err_tx_irq; > + } > + > + tasklet_init(&msgq->txdone_tasklet, gh_msgq_txdone_tasklet, (unsigned long)msgq); > + > + ret = mbox_controller_register(&msgq->mbox); > + if (ret) > + goto err_rx_irq; > + > + ret = mbox_bind_client(gunyah_msgq_chan(msgq), cl); > + if (ret) > + goto err_mbox; > + > + return 0; > +err_mbox: > + mbox_controller_unregister(&msgq->mbox); > +err_rx_irq: > + if (gh_msgq_has_rx(msgq)) > + free_irq(msgq->rx_ghrsc.irq, msgq); > +err_tx_irq: > + if (gh_msgq_has_tx(msgq)) > + free_irq(msgq->tx_ghrsc.irq, msgq); > +err_chans: > + kfree(msgq->mbox.chans); > + return ret; > +} > +EXPORT_SYMBOL_GPL(gunyah_msgq_init); > + > +void gunyah_msgq_remove(struct gunyah_msgq *msgq) > +{ > + if (gh_msgq_has_tx(msgq)) > + free_irq(msgq->tx_ghrsc.irq, msgq);
Missing:
+ if (gh_msgq_has_rx(msgq)) + free_irq(msgq->rx_ghrsc.irq, msgq);
> + > + kfree(msgq->mbox.chans); > +} > +EXPORT_SYMBOL_GPL(gunyah_msgq_remove); > + > + > +static int __init gh_msgq_init(void) > +{ > + if (GH_API_INFO_API_VERSION(gunyah_api.api_info) != GUNYAH_API_V1) { > + pr_warn("Unrecognized gunyah version: %llu. Currently supported: %d\n", > + GH_API_INFO_API_VERSION(gunyah_api.api_info), GUNYAH_API_V1); > + return -ENODEV; > + } > + > + return 0; > +} > +module_init(gh_msgq_init); > + > +static void __exit gh_msgq_exit(void) > +{ > +} > +module_exit(gh_msgq_exit);
Not needed
> + > +MODULE_LICENSE("GPL"); > +MODULE_DESCRIPTION("Gunyah Message Queue Driver"); > diff --git a/drivers/virt/gunyah/Kconfig b/drivers/virt/gunyah/Kconfig > index 7ac917e0aa3f..f4c822a82f1a 100644 > --- a/drivers/virt/gunyah/Kconfig > +++ b/drivers/virt/gunyah/Kconfig > @@ -4,6 +4,8 @@ config GUNYAH > tristate "Gunyah Virtualization drivers" > depends on ARM64 > select AUXILIARY_BUS > + select MAILBOX > + select GUNYAH_MESSAGE_QUEUES > help > The Gunyah drivers are the helper interfaces that runs in a guest VM > such as basic inter-VM IPC and signaling mechanisms, and higher level > diff --git a/include/linux/gunyah.h b/include/linux/gunyah.h > new file mode 100644 > index 000000000000..0e9709555c79 > --- /dev/null > +++ b/include/linux/gunyah.h > @@ -0,0 +1,67 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved. > + */ > + > +#ifndef _GUNYAH_H > +#define _GUNYAH_H > + > +#include <linux/mailbox_controller.h> > +#include <linux/mailbox_client.h> > +#include <linux/interrupt.h> > + > +#include <asm-generic/gunyah.h> > + > +/* Follows resource manager's resource types for VM_GET_HYP_RESOURCES */ > +enum gunyah_resource_type { > + GUNYAH_RESOURCE_TYPE_BELL_TX = 0, > + GUNYAH_RESOURCE_TYPE_BELL_RX = 1, > + GUNYAH_RESOURCE_TYPE_MSGQ_TX = 2, > + GUNYAH_RESOURCE_TYPE_MSGQ_RX = 3, > + GUNYAH_RESOURCE_TYPE_VCPU = 4, > +}; > + > +struct gunyah_resource { > + enum gunyah_resource_type type; > + u64 capid; > + int irq; > +}; > + > +/** > + * Gunyah Message Queues > + */ > + > +#define GH_MSGQ_MAX_MSG_SIZE 240 > + > +struct gunyah_msgq_tx_data { > + size_t length; > + bool push; > + char data[]; > +}; > + > +struct gunyah_msgq_rx_data { > + size_t length; > + char data[GH_MSGQ_MAX_MSG_SIZE]; > +}; > + > +struct gunyah_msgq { > + struct gunyah_resource tx_ghrsc; > + struct gunyah_resource rx_ghrsc; > + > + /* msgq private */ > + int last_status; > + struct mbox_controller mbox; > + struct tasklet_struct txdone_tasklet; > +}; > + > + > +int gunyah_msgq_init(struct device *parent, struct gunyah_msgq *msgq, struct mbox_client *cl, > + struct gunyah_resource *tx_ghrsc, struct gunyah_resource *rx_ghrsc); > +void gunyah_msgq_remove(struct gunyah_msgq *msgq); > + > +static inline struct mbox_chan *gunyah_msgq_chan(struct gunyah_msgq *msgq) > +{ > + return &msgq->mbox.chans[0]; > +} > + > +#endif -- With best wishes Dmitry
| |