drivers/infiniband/hw/hns/hns_roce_alloc.c
Source file repositories/reference/linux-study-clean/drivers/infiniband/hw/hns/hns_roce_alloc.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/infiniband/hw/hns/hns_roce_alloc.c- Extension
.c- Size
- 5339 bytes
- Lines
- 188
- 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.
- 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.
- Touches IRQ or DMA behavior; this matters for the representative real-device path.
- Allocates kernel memory; connect allocation flags and lifetime to context constraints.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/vmalloc.hrdma/iter.hhns_roce_device.h
Detected Declarations
function Copyrightfunction hns_roce_get_kmem_bufsfunction hns_roce_get_umem_bufsfunction hns_roce_cleanup_bitmap
Annotated Snippet
#include <linux/vmalloc.h>
#include <rdma/iter.h>
#include "hns_roce_device.h"
void hns_roce_buf_free(struct hns_roce_dev *hr_dev, struct hns_roce_buf *buf)
{
struct hns_roce_buf_list *trunks;
u32 i;
if (!buf)
return;
trunks = buf->trunk_list;
if (trunks) {
buf->trunk_list = NULL;
for (i = 0; i < buf->ntrunks; i++)
dma_free_coherent(hr_dev->dev, 1 << buf->trunk_shift,
trunks[i].buf, trunks[i].map);
kfree(trunks);
}
kfree(buf);
}
/*
* Allocate the dma buffer for storing ROCEE table entries
*
* @size: required size
* @page_shift: the unit size in a continuous dma address range
* @flags: HNS_ROCE_BUF_ flags to control the allocation flow.
*/
struct hns_roce_buf *hns_roce_buf_alloc(struct hns_roce_dev *hr_dev, u32 size,
u32 page_shift, u32 flags)
{
u32 trunk_size, page_size, alloced_size;
struct hns_roce_buf_list *trunks;
struct hns_roce_buf *buf;
gfp_t gfp_flags;
u32 ntrunk, i;
/* The minimum shift of the page accessed by hw is HNS_HW_PAGE_SHIFT */
if (WARN_ON(page_shift < HNS_HW_PAGE_SHIFT))
return ERR_PTR(-EINVAL);
gfp_flags = (flags & HNS_ROCE_BUF_NOSLEEP) ? GFP_ATOMIC : GFP_KERNEL;
buf = kzalloc_obj(*buf, gfp_flags);
if (!buf)
return ERR_PTR(-ENOMEM);
buf->page_shift = page_shift;
page_size = 1 << buf->page_shift;
/* Calc the trunk size and num by required size and page_shift */
if (flags & HNS_ROCE_BUF_DIRECT) {
buf->trunk_shift = order_base_2(ALIGN(size, PAGE_SIZE));
ntrunk = 1;
} else {
buf->trunk_shift = order_base_2(ALIGN(page_size, PAGE_SIZE));
ntrunk = DIV_ROUND_UP(size, 1 << buf->trunk_shift);
}
trunks = kzalloc_objs(*trunks, ntrunk, gfp_flags);
if (!trunks) {
kfree(buf);
return ERR_PTR(-ENOMEM);
}
trunk_size = 1 << buf->trunk_shift;
alloced_size = 0;
for (i = 0; i < ntrunk; i++) {
trunks[i].buf = dma_alloc_coherent(hr_dev->dev, trunk_size,
&trunks[i].map, gfp_flags);
if (!trunks[i].buf)
break;
alloced_size += trunk_size;
}
buf->ntrunks = i;
/* In nofail mode, it's only failed when the alloced size is 0 */
if ((flags & HNS_ROCE_BUF_NOFAIL) ? i == 0 : i != ntrunk) {
for (i = 0; i < buf->ntrunks; i++)
dma_free_coherent(hr_dev->dev, trunk_size,
trunks[i].buf, trunks[i].map);
kfree(trunks);
kfree(buf);
return ERR_PTR(-ENOMEM);
Annotation
- Immediate include surface: `linux/vmalloc.h`, `rdma/iter.h`, `hns_roce_device.h`.
- Detected declarations: `function Copyright`, `function hns_roce_get_kmem_bufs`, `function hns_roce_get_umem_bufs`, `function hns_roce_cleanup_bitmap`.
- Atlas domain: Driver Families / drivers/infiniband.
- Implementation status: source implementation candidate.
- IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.