[PATCHv13 10/11] nvme: register fdp parameters with the block layer

[Hannes Reinecke]

On 12/10/24 20:47, Keith Busch wrote:
> From: Keith Busch <kbusch at kernel.org>
> 
> Register the device data placement limits if supported. This is just
> registering the limits with the block layer. Nothing beyond reporting
> these attributes is happening in this patch.
> 
> Merges parts from a patch by Christoph Hellwig <hch at lst.de>
> Link: https://lore.kernel.org/linux-nvme/20241119121632.1225556-15-hch@lst.de/
> 
> Signed-off-by: Keith Busch <kbusch at kernel.org>
> ---
>   drivers/nvme/host/core.c | 139 +++++++++++++++++++++++++++++++++++++++
>   drivers/nvme/host/nvme.h |   2 +
>   2 files changed, 141 insertions(+)
> 
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index c2a3585a3fa59..f7aeda601fcd6 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -38,6 +38,8 @@ struct nvme_ns_info {
>   	u32 nsid;
>   	__le32 anagrpid;
>   	u8 pi_offset;
> +	u16 endgid;
> +	u64 runs;
>   	bool is_shared;
>   	bool is_readonly;
>   	bool is_ready;
> @@ -1613,6 +1615,7 @@ static int nvme_ns_info_from_identify(struct nvme_ctrl *ctrl,
>   	info->is_shared = id->nmic & NVME_NS_NMIC_SHARED;
>   	info->is_readonly = id->nsattr & NVME_NS_ATTR_RO;
>   	info->is_ready = true;
> +	info->endgid = le16_to_cpu(id->endgid);
>   	if (ctrl->quirks & NVME_QUIRK_BOGUS_NID) {
>   		dev_info(ctrl->device,
>   			 "Ignoring bogus Namespace Identifiers\n");
> @@ -1653,6 +1656,7 @@ static int nvme_ns_info_from_id_cs_indep(struct nvme_ctrl *ctrl,
>   		info->is_ready = id->nstat & NVME_NSTAT_NRDY;
>   		info->is_rotational = id->nsfeat & NVME_NS_ROTATIONAL;
>   		info->no_vwc = id->nsfeat & NVME_NS_VWC_NOT_PRESENT;
> +		info->endgid = le16_to_cpu(id->endgid);
>   	}
>   	kfree(id);
>   	return ret;
> @@ -2147,6 +2151,127 @@ static int nvme_update_ns_info_generic(struct nvme_ns *ns,
>   	return ret;
>   }
>   
> +static int nvme_query_fdp_granularity(struct nvme_ctrl *ctrl,
> +				      struct nvme_ns_info *info, u8 fdp_idx)
> +{
> +	struct nvme_fdp_config_log hdr, *h;
> +	struct nvme_fdp_config_desc *desc;
> +	size_t size = sizeof(hdr);
> +	int i, n, ret;
> +	void *log;
> +
> +	ret = nvme_get_log_lsi(ctrl, 0, NVME_LOG_FDP_CONFIGS, 0,
> +			       NVME_CSI_NVM, &hdr, size, 0, info->endgid);
> +	if (ret) {
> +		dev_warn(ctrl->device,
> +			 "FDP configs log header status:0x%x endgid:%x\n", ret,
> +			 info->endgid);
> +		return ret;
> +	}
> +
> +	size = le32_to_cpu(hdr.sze);

size should be bounded to avoid overly large memory allocations when the 
header is garbled.

> +	h = kzalloc(size, GFP_KERNEL);
> +	if (!h) {
> +		dev_warn(ctrl->device,
> +			 "failed to allocate %lu bytes for FDP config log\n",
> +			 size);
> +		return -ENOMEM;
> +	}
> +
> +	ret = nvme_get_log_lsi(ctrl, 0, NVME_LOG_FDP_CONFIGS, 0,
> +			       NVME_CSI_NVM, h, size, 0, info->endgid);
> +	if (ret) {
> +		dev_warn(ctrl->device,
> +			 "FDP configs log status:0x%x endgid:%x\n", ret,
> +			 info->endgid);
> +		goto out;
> +	}
> +
> +	n = le16_to_cpu(h->numfdpc) + 1;
> +	if (fdp_idx > n) {
> +		dev_warn(ctrl->device, "FDP index:%d out of range:%d\n",
> +			 fdp_idx, n);
> +		/* Proceed without registering FDP streams */
> +		ret = 0;
> +		goto out;
> +	}
> +
> +	log = h + 1;
> +	desc = log;
> +	for (i = 0; i < fdp_idx; i++) {
> +		log += le16_to_cpu(desc->dsze);
> +		desc = log;

Check for the size of 'h' to ensure that you are not
falling over the end ...


Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare at suse.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
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