From b21dcebfa6b372cd91bf42a30f1d8a1a525f329b Mon Sep 17 00:00:00 2001 From: Aaron Williams Date: Thu, 22 Aug 2019 20:37:26 -0700 Subject: [PATCH] nvme: Fix PRP Offset Invalid When large writes take place I saw a Samsung EVO 970+ return a status value of 0x13, PRP Offset Invalid. I tracked this down to the improper handling of PRP entries. The blocks the PRP entries are placed in cannot cross a page boundary and thus should be allocated on page boundaries. This is how the Linux kernel driver works. With this patch, the PRP pool is allocated on a page boundary and other than the very first allocation, the pool size is a multiple of the page size. Each page can hold (4096 / 8) - 1 entries since the last entry must point to the next page in the pool. Signed-off-by: Aaron Williams Reviewed-by: Bin Meng --- drivers/nvme/nvme.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) diff --git a/drivers/nvme/nvme.c b/drivers/nvme/nvme.c index d4965e2ef6..47f101e280 100644 --- a/drivers/nvme/nvme.c +++ b/drivers/nvme/nvme.c @@ -73,6 +73,9 @@ static int nvme_setup_prps(struct nvme_dev *dev, u64 *prp2, u64 *prp_pool; int length = total_len; int i, nprps; + u32 prps_per_page = (page_size >> 3) - 1; + u32 num_pages; + length -= (page_size - offset); if (length <= 0) { @@ -89,15 +92,20 @@ static int nvme_setup_prps(struct nvme_dev *dev, u64 *prp2, } nprps = DIV_ROUND_UP(length, page_size); + num_pages = DIV_ROUND_UP(nprps, prps_per_page); if (nprps > dev->prp_entry_num) { free(dev->prp_pool); - dev->prp_pool = malloc(nprps << 3); + /* + * Always increase in increments of pages. It doesn't waste + * much memory and reduces the number of allocations. + */ + dev->prp_pool = memalign(page_size, num_pages * page_size); if (!dev->prp_pool) { printf("Error: malloc prp_pool fail\n"); return -ENOMEM; } - dev->prp_entry_num = nprps; + dev->prp_entry_num = prps_per_page * num_pages; } prp_pool = dev->prp_pool; @@ -788,14 +796,6 @@ static int nvme_probe(struct udevice *udev) } memset(ndev->queues, 0, NVME_Q_NUM * sizeof(struct nvme_queue *)); - ndev->prp_pool = malloc(MAX_PRP_POOL); - if (!ndev->prp_pool) { - ret = -ENOMEM; - printf("Error: %s: Out of memory!\n", udev->name); - goto free_nvme; - } - ndev->prp_entry_num = MAX_PRP_POOL >> 3; - ndev->cap = nvme_readq(&ndev->bar->cap); ndev->q_depth = min_t(int, NVME_CAP_MQES(ndev->cap) + 1, NVME_Q_DEPTH); ndev->db_stride = 1 << NVME_CAP_STRIDE(ndev->cap); @@ -805,6 +805,15 @@ static int nvme_probe(struct udevice *udev) if (ret) goto free_queue; + /* Allocate after the page size is known */ + ndev->prp_pool = memalign(ndev->page_size, MAX_PRP_POOL); + if (!ndev->prp_pool) { + ret = -ENOMEM; + printf("Error: %s: Out of memory!\n", udev->name); + goto free_nvme; + } + ndev->prp_entry_num = MAX_PRP_POOL >> 3; + ret = nvme_setup_io_queues(ndev); if (ret) goto free_queue; -- 2.39.5