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

Hannes Reinecke
2024-12-11T11:25:18Z

On 12/10/24 20:47, Keith Busch wrote:
> From: Keith Busch <kbusch@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@lst.de>
> Link: https://lore.kernel.org/linux-nvme/20241119121632.1225556-15-hch@lst.de/
>
> Signed-off-by: Keith Busch <kbusch@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@suse.de +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich