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nvme: new define for size of host memory buffer sizes

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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
This commit is contained in:
Warner Losh 2022-04-08 23:01:06 -06:00
parent 0d46a96abf
commit 214df80a9c
2 changed files with 7 additions and 4 deletions
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3
sys/dev/nvme/nvme.h
View File

@ -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)

8
sys/dev/nvme/nvme_ctrlr.c
View File

@ -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 @@ nvme_ctrlr_hmb_alloc(struct nvme_controller *ctrlr)
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);