drivers/infiniband/hw/ionic/ionic_pgtbl.c

Source file repositories/reference/linux-study-clean/drivers/infiniband/hw/ionic/ionic_pgtbl.c

File Facts

System
Linux kernel
Corpus path
drivers/infiniband/hw/ionic/ionic_pgtbl.c
Extension
.c
Size
2796 bytes
Lines
144
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

// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2018-2025, Advanced Micro Devices, Inc. */

#include <linux/mman.h>
#include <linux/dma-mapping.h>

#include "ionic_fw.h"
#include "ionic_ibdev.h"

__le64 ionic_pgtbl_dma(struct ionic_tbl_buf *buf, u64 va)
{
	u64 pg_mask = BIT_ULL(buf->page_size_log2) - 1;
	u64 dma;

	if (!buf->tbl_pages)
		return cpu_to_le64(0);

	if (buf->tbl_pages > 1)
		return cpu_to_le64(buf->tbl_dma);

	if (buf->tbl_buf)
		dma = le64_to_cpu(buf->tbl_buf[0]);
	else
		dma = buf->tbl_dma;

	return cpu_to_le64(dma + (va & pg_mask));
}

__be64 ionic_pgtbl_off(struct ionic_tbl_buf *buf, u64 va)
{
	if (buf->tbl_pages > 1) {
		u64 pg_mask = BIT_ULL(buf->page_size_log2) - 1;

		return cpu_to_be64(va & pg_mask);
	}

	return 0;
}

int ionic_pgtbl_page(struct ionic_tbl_buf *buf, u64 dma)
{
	if (unlikely(buf->tbl_pages == buf->tbl_limit))
		return -ENOMEM;

	if (buf->tbl_buf)
		buf->tbl_buf[buf->tbl_pages] = cpu_to_le64(dma);
	else
		buf->tbl_dma = dma;

	++buf->tbl_pages;

	return 0;
}

static int ionic_tbl_buf_alloc(struct ionic_ibdev *dev,
			       struct ionic_tbl_buf *buf)
{
	int rc;

	buf->tbl_size = buf->tbl_limit * sizeof(*buf->tbl_buf);
	buf->tbl_buf = kmalloc(buf->tbl_size, GFP_KERNEL);
	if (!buf->tbl_buf)
		return -ENOMEM;

	buf->tbl_dma = dma_map_single(dev->lif_cfg.hwdev, buf->tbl_buf,
				      buf->tbl_size, DMA_TO_DEVICE);
	rc = dma_mapping_error(dev->lif_cfg.hwdev, buf->tbl_dma);
	if (rc) {
		kfree(buf->tbl_buf);
		return rc;
	}

	return 0;
}

static int ionic_pgtbl_umem(struct ionic_tbl_buf *buf, struct ib_umem *umem)
{
	struct ib_block_iter biter;
	u64 page_dma;
	int rc;

	rdma_umem_for_each_dma_block(umem, &biter, BIT_ULL(buf->page_size_log2)) {
		page_dma = rdma_block_iter_dma_address(&biter);
		rc = ionic_pgtbl_page(buf, page_dma);
		if (rc)
			return rc;
	}

	return 0;
}

Annotation

Implementation Notes