drivers/infiniband/hw/vmw_pvrdma/pvrdma_cmd.c

Source file repositories/reference/linux-study-clean/drivers/infiniband/hw/vmw_pvrdma/pvrdma_cmd.c

File Facts

System
Linux kernel
Corpus path
drivers/infiniband/hw/vmw_pvrdma/pvrdma_cmd.c
Extension
.c
Size
3853 bytes
Lines
120
Domain
Driver Families
Bucket
drivers/infiniband
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

#include <linux/list.h>

#include "pvrdma.h"

#define PVRDMA_CMD_TIMEOUT	10000 /* ms */

static inline int pvrdma_cmd_recv(struct pvrdma_dev *dev,
				  union pvrdma_cmd_resp *resp,
				  unsigned resp_code)
{
	int err;

	dev_dbg(&dev->pdev->dev, "receive response from device\n");

	err = wait_for_completion_interruptible_timeout(&dev->cmd_done,
			msecs_to_jiffies(PVRDMA_CMD_TIMEOUT));
	if (err == 0 || err == -ERESTARTSYS) {
		dev_warn(&dev->pdev->dev,
			 "completion timeout or interrupted\n");
		return -ETIMEDOUT;
	}

	spin_lock(&dev->cmd_lock);
	memcpy(resp, dev->resp_slot, sizeof(*resp));
	spin_unlock(&dev->cmd_lock);

	if (resp->hdr.ack != resp_code) {
		dev_warn(&dev->pdev->dev,
			 "unknown response %#x expected %#x\n",
			 resp->hdr.ack, resp_code);
		return -EFAULT;
	}

	return 0;
}

int
pvrdma_cmd_post(struct pvrdma_dev *dev, union pvrdma_cmd_req *req,
		union pvrdma_cmd_resp *resp, unsigned resp_code)
{
	int err;

	dev_dbg(&dev->pdev->dev, "post request to device\n");

	/* Serializiation */
	down(&dev->cmd_sema);

	BUILD_BUG_ON(sizeof(union pvrdma_cmd_req) !=
		     sizeof(struct pvrdma_cmd_modify_qp));

	spin_lock(&dev->cmd_lock);
	memcpy(dev->cmd_slot, req, sizeof(*req));
	spin_unlock(&dev->cmd_lock);

	init_completion(&dev->cmd_done);
	pvrdma_write_reg(dev, PVRDMA_REG_REQUEST, 0);

	/* Make sure the request is written before reading status. */
	mb();

	err = pvrdma_read_reg(dev, PVRDMA_REG_ERR);
	if (err == 0) {
		if (resp != NULL)
			err = pvrdma_cmd_recv(dev, resp, resp_code);
	} else {
		dev_warn(&dev->pdev->dev,
			 "failed to write request error reg: %d\n", err);
		err = -EFAULT;
	}

	up(&dev->cmd_sema);

	return err;
}

Annotation

Implementation Notes