git: 214df80a9cb3 - main - nvme: new define for size of host memory buffer sizes

The branch main has been updated by imp:

URL: https://cgit.FreeBSD.org/src/commit/?id=214df80a9cb3e95a140b13af7d19deec2bbfae76

commit 214df80a9cb3e95a140b13af7d19deec2bbfae76
Author:     Warner Losh <imp@FreeBSD.org>
AuthorDate: 2022-04-09 05:01:06 +0000
Commit:     Warner Losh <imp@FreeBSD.org>
CommitDate: 2022-04-09 05:05:25 +0000

    nvme: new define for size of host memory buffer sizes
    
    The nvme spec defines the various fields that specify sizes for host
    memory buffers in terms of 4096 chunks. So, rather than use a bare 4096
    here, use NVME_HMB_UNITS. This is explicitly not the host page size of
    4096, nor the default memory page size (mps) of the NVMe drive, but its
    own thing and needs its own define.
    
    No functional change is intended, only the logical spelling of 4k.
    
    Sponsored by:           Netflix
---
 sys/dev/nvme/nvme.h       | 3 +++
 sys/dev/nvme/nvme_ctrlr.c | 8 ++++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/sys/dev/nvme/nvme.h b/sys/dev/nvme/nvme.h
index f2ef2467c9b1..55e94c40dd2c 100644
--- a/sys/dev/nvme/nvme.h
+++ b/sys/dev/nvme/nvme.h
@@ -62,6 +62,9 @@
 /* Cap transfers by the maximum addressable by page-sized PRP (4KB -> 2MB). */
 #define NVME_MAX_XFER_SIZE		MIN(maxphys, (PAGE_SIZE/8*PAGE_SIZE))
 
+/* Host memory buffer sizes are always in 4096 byte chunks */
+#define	NVME_HMB_UNITS			4096
+
 /* Register field definitions */
 #define NVME_CAP_LO_REG_MQES_SHIFT			(0)
 #define NVME_CAP_LO_REG_MQES_MASK			(0xFFFF)
diff --git a/sys/dev/nvme/nvme_ctrlr.c b/sys/dev/nvme/nvme_ctrlr.c
index 95a2b5c4285d..6996b3151b0d 100644
--- a/sys/dev/nvme/nvme_ctrlr.c
+++ b/sys/dev/nvme/nvme_ctrlr.c
@@ -936,11 +936,11 @@ nvme_ctrlr_hmb_alloc(struct nvme_controller *ctrlr)
 	max = (uint64_t)physmem * PAGE_SIZE / 20;
 	TUNABLE_UINT64_FETCH("hw.nvme.hmb_max", &max);
 
-	min = (long long unsigned)ctrlr->cdata.hmmin * 4096;
+	min = (long long unsigned)ctrlr->cdata.hmmin * NVME_HMB_UNITS;
 	if (max == 0 || max < min)
 		return;
-	pref = MIN((long long unsigned)ctrlr->cdata.hmpre * 4096, max);
-	minc = MAX(ctrlr->cdata.hmminds * 4096, PAGE_SIZE);
+	pref = MIN((long long unsigned)ctrlr->cdata.hmpre * NVME_HMB_UNITS, max);
+	minc = MAX(ctrlr->cdata.hmminds * NVME_HMB_UNITS, PAGE_SIZE);
 	if (min > 0 && ctrlr->cdata.hmmaxd > 0)
 		minc = MAX(minc, min / ctrlr->cdata.hmmaxd);
 	ctrlr->hmb_chunk = pref;
@@ -1023,7 +1023,7 @@ again:
 	for (i = 0; i < ctrlr->hmb_nchunks; i++) {
 		ctrlr->hmb_desc_vaddr[i].addr =
 		    htole64(ctrlr->hmb_chunks[i].hmbc_paddr);
-		ctrlr->hmb_desc_vaddr[i].size = htole32(ctrlr->hmb_chunk / 4096);
+		ctrlr->hmb_desc_vaddr[i].size = htole32(ctrlr->hmb_chunk / NVME_HMB_UNITS);
 	}
 	bus_dmamap_sync(ctrlr->hmb_desc_tag, ctrlr->hmb_desc_map,
 	    BUS_DMASYNC_PREWRITE);