drivers/infiniband/hw/hfi1/user_sdma.c

Source file repositories/reference/linux-study-clean/drivers/infiniband/hw/hfi1/user_sdma.c

File Facts

System
Linux kernel
Corpus path
drivers/infiniband/hw/hfi1/user_sdma.c
Extension
.c
Size
34480 bytes
Lines
1223
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

if (req->data_iovs < 2) {
			SDMA_DBG(req,
				 "Not enough vectors for expected request");
			ret = -EINVAL;
			goto free_req;
		}
		req->data_iovs--;
	}

	if (!info.npkts || req->data_iovs > MAX_VECTORS_PER_REQ) {
		SDMA_DBG(req, "Too many vectors (%u/%u)", req->data_iovs,
			 MAX_VECTORS_PER_REQ);
		ret = -EINVAL;
		goto free_req;
	}

	/* Copy the header from the user buffer */
	ret = copy_from_user(&req->hdr, iovec[idx].iov_base + sizeof(info),
			     sizeof(req->hdr));
	if (ret) {
		SDMA_DBG(req, "Failed to copy header template (%d)", ret);
		ret = -EFAULT;
		goto free_req;
	}

	/* If Static rate control is not enabled, sanitize the header. */
	if (!HFI1_CAP_IS_USET(STATIC_RATE_CTRL))
		req->hdr.pbc[2] = 0;

	/* Validate the opcode. Do not trust packets from user space blindly. */
	opcode = (be32_to_cpu(req->hdr.bth[0]) >> 24) & 0xff;
	if ((opcode & USER_OPCODE_CHECK_MASK) !=
	     USER_OPCODE_CHECK_VAL) {
		SDMA_DBG(req, "Invalid opcode (%d)", opcode);
		ret = -EINVAL;
		goto free_req;
	}
	/*
	 * Validate the vl. Do not trust packets from user space blindly.
	 * VL comes from PBC, SC comes from LRH, and the VL needs to
	 * match the SC look up.
	 */
	vl = (le16_to_cpu(req->hdr.pbc[0]) >> 12) & 0xF;
	sc = (((be16_to_cpu(req->hdr.lrh[0]) >> 12) & 0xF) |
	      (((le16_to_cpu(req->hdr.pbc[1]) >> 14) & 0x1) << 4));
	if (vl >= dd->pport->vls_operational ||
	    vl != sc_to_vlt(dd, sc)) {
		SDMA_DBG(req, "Invalid SC(%u)/VL(%u)", sc, vl);
		ret = -EINVAL;
		goto free_req;
	}

	/* Checking P_KEY for requests from user-space */
	pkey = (u16)be32_to_cpu(req->hdr.bth[0]);
	slid = be16_to_cpu(req->hdr.lrh[3]);
	if (egress_pkey_check(dd->pport, slid, pkey, sc, PKEY_CHECK_INVALID)) {
		ret = -EINVAL;
		goto free_req;
	}

	/*
	 * Also should check the BTH.lnh. If it says the next header is GRH then
	 * the RXE parsing will be off and will land in the middle of the KDETH
	 * or miss it entirely.
	 */
	if ((be16_to_cpu(req->hdr.lrh[0]) & 0x3) == HFI1_LRH_GRH) {
		SDMA_DBG(req, "User tried to pass in a GRH");
		ret = -EINVAL;
		goto free_req;
	}

	req->koffset = le32_to_cpu(req->hdr.kdeth.swdata[6]);
	/*
	 * Calculate the initial TID offset based on the values of
	 * KDETH.OFFSET and KDETH.OM that are passed in.
	 */
	req->tidoffset = KDETH_GET(req->hdr.kdeth.ver_tid_offset, OFFSET) *
		(KDETH_GET(req->hdr.kdeth.ver_tid_offset, OM) ?
		 KDETH_OM_LARGE : KDETH_OM_SMALL);
	trace_hfi1_sdma_user_initial_tidoffset(dd, uctxt->ctxt, fd->subctxt,
					       info.comp_idx, req->tidoffset);
	idx++;

	/* Save all the IO vector structures */
	for (i = 0; i < req->data_iovs; i++) {
		req->iovs[i].offset = 0;
		INIT_LIST_HEAD(&req->iovs[i].list);
		memcpy(&req->iovs[i].iov,
		       iovec + idx++,
		       sizeof(req->iovs[i].iov));

Annotation

Implementation Notes