There is no need to create multiple dma bounce buffers as the BIOS disk code isn't reentrant capable.
Signed-off-by: Kevin O'Connor kevin@koconnor.net
---
This is a minor cleanup on top of the previous nvme code series.
-Kevin
--- src/hw/nvme-int.h | 3 --- src/hw/nvme.c | 14 +++++++++----- 2 files changed, 9 insertions(+), 8 deletions(-)
diff --git a/src/hw/nvme-int.h b/src/hw/nvme-int.h index f0d717d..f9c807e 100644 --- a/src/hw/nvme-int.h +++ b/src/hw/nvme-int.h @@ -117,9 +117,6 @@ struct nvme_namespace { u32 block_size; u32 metadata_size; u32 max_req_size; - - /* Page aligned buffer of size NVME_PAGE_SIZE. */ - char *dma_buffer; };
/* Data structures for NVMe admin identify commands */ diff --git a/src/hw/nvme.c b/src/hw/nvme.c index 39b9138..0ba981c 100644 --- a/src/hw/nvme.c +++ b/src/hw/nvme.c @@ -20,6 +20,9 @@ #include "nvme.h" #include "nvme-int.h"
+// Page aligned "dma bounce buffer" of size NVME_PAGE_SIZE in high memory +static void *nvme_dma_buffer; + static void * zalloc_page_aligned(struct zone_s *zone, u32 size) { @@ -294,7 +297,8 @@ nvme_probe_ns(struct nvme_ctrl *ctrl, u32 ns_idx, u8 mdts) ns->max_req_size = -1U; }
- ns->dma_buffer = zalloc_page_aligned(&ZoneHigh, NVME_PAGE_SIZE); + if (!nvme_dma_buffer) + nvme_dma_buffer = zalloc_page_aligned(&ZoneHigh, NVME_PAGE_SIZE);
char *desc = znprintf(MAXDESCSIZE, "NVMe NS %u: %llu MiB (%llu %u-byte " "blocks + %u-byte metadata)", @@ -460,12 +464,12 @@ nvme_bounce_xfer(struct nvme_namespace *ns, u64 lba, void *buf, u16 count, u16 blocks = count < max_blocks ? count : max_blocks;
if (write) - memcpy(ns->dma_buffer, buf, blocks * ns->block_size); + memcpy(nvme_dma_buffer, buf, blocks * ns->block_size);
- int res = nvme_io_xfer(ns, lba, ns->dma_buffer, NULL, blocks, write); + int res = nvme_io_xfer(ns, lba, nvme_dma_buffer, NULL, blocks, write);
if (!write && res >= 0) - memcpy(buf, ns->dma_buffer, res * ns->block_size); + memcpy(buf, nvme_dma_buffer, res * ns->block_size);
return res; } @@ -499,7 +503,7 @@ nvme_prpl_xfer(struct nvme_namespace *ns, u64 lba, void *buf, u16 count, if ((ns->block_size * count) > (NVME_PAGE_SIZE * 2)) { /* We need to describe more than 2 pages, build PRP List */ u32 prpl_len = 0; - u64 *prpl = (void*)ns->dma_buffer; + u64 *prpl = nvme_dma_buffer; int first_page = 1; for (; size > 0; base += NVME_PAGE_SIZE, size -= NVME_PAGE_SIZE) { if (first_page) {