[PATCH 4/5] lnvm: introduce chunk-log command for chunk info

[mb@lightnvm.io (Matias Bjørling)]

On 23/07/2019 20.36, Minwoo Im wrote:
> To retrieve the chunk information from the nvme namespae for the given
> OCSSD, we can just do like:
> 	nvme lnvm chunk-log /dev/nvme0n1 --output-format=normal
>
> This will calculate the data length from the geometry data structure
> which might be retrieved by a Geometry command(Identity for 1.2 spec.).
> Then it will request get log page API for 1.3 NVMe spec to get the
> entries which indicate chunk information.
>
> Cc: Keith Busch <kbusch at kernel.org>
> Cc: Matias Bjorling <mb at lightnvm.io>
> Signed-off-by: Minwoo Im <minwoo.im.dev at gmail.com>
> ---
>   nvme-lightnvm.c          | 37 ++++++++++++++++++
>   nvme-lightnvm.h          |  1 +
>   plugins/lnvm/lnvm-nvme.c | 84 ++++++++++++++++++++++++++++++++++++++++
>   plugins/lnvm/lnvm-nvme.h |  1 +
>   4 files changed, 123 insertions(+)
>
> diff --git a/nvme-lightnvm.c b/nvme-lightnvm.c
> index 2e665bf..8fa8f3f 100644
> --- a/nvme-lightnvm.c
> +++ b/nvme-lightnvm.c
> @@ -465,6 +465,43 @@ int lnvm_do_id_ns(int fd, int nsid, unsigned int flags)
>   	return err;
>   }
>   
> +static void show_lnvm_chunk_log(struct nvme_nvm_chunk_desc *chunk_log,
> +				__u32 data_len)
> +{
> +	int nr_entry = data_len / sizeof(struct nvme_nvm_chunk_desc);
> +	int idx;
> +
> +	for (idx = 0; idx < nr_entry; idx++) {
> +		struct nvme_nvm_chunk_desc *desc = &chunk_log[idx];
> +
> +		printf(" [%5d] { ", idx);
> +		printf("cs: %#x", desc->cs);
> +		printf(", ct: %#x", desc->ct);
> +		printf(", wli: %d", desc->wli);
> +		printf(", slba: 0x%016"PRIx64, le64_to_cpu(desc->slba));
> +		printf(", cnlb: 0x%016"PRIx64, le64_to_cpu(desc->cnlb));
> +		printf(", wp: 0x%016"PRIx64" }\n", le64_to_cpu(desc->wp));
> +	}
> +}
> +
> +int lnvm_do_chunk_log(int fd, __u32 nsid, __u32 data_len, void *data,
> +			unsigned int flags)
> +{
> +	int err;
> +
> +	err = nvme_get_log13(fd, nsid, NVM_LID_CHUNK_INFO, 0, 0, 0,
> +			false, data_len, data);
> +	if (!err) {
> +		if (flags & RAW)
> +			d_raw(data, data_len);
> +		else
> +			show_lnvm_chunk_log(data, data_len);
> +	} else if (err > 0)
> +		fprintf(stderr, "NVMe Status:%s(%x) NSID:%d\n",
> +			nvme_status_to_string(err), err, nsid);
> +	return err;
> +}
> +
>   static void show_lnvm_bbtbl(struct nvme_nvm_bb_tbl *tbl)
>   {
>   	printf("verid    : %#x\n", (uint16_t)le16_to_cpu(tbl->verid));
> diff --git a/nvme-lightnvm.h b/nvme-lightnvm.h
> index 7a8ef7d..19660b7 100644
> --- a/nvme-lightnvm.h
> +++ b/nvme-lightnvm.h
> @@ -322,6 +322,7 @@ int lnvm_do_create_tgt(char *, char *, char *, int, int, int, int);
>   int lnvm_do_remove_tgt(char *);
>   int lnvm_do_factory_init(char *, int, int, int);
>   int lnvm_do_id_ns(int, int, unsigned int);
> +int lnvm_do_chunk_log(int, __u32, __u32, void *, unsigned int);
>   int lnvm_do_get_bbtbl(int, int, int, int, unsigned int);
>   int lnvm_do_set_bbtbl(int, int, int, int, int, int, __u8);
>   
> diff --git a/plugins/lnvm/lnvm-nvme.c b/plugins/lnvm/lnvm-nvme.c
> index 754931a..6f2724a 100644
> --- a/plugins/lnvm/lnvm-nvme.c
> +++ b/plugins/lnvm/lnvm-nvme.c
> @@ -1,5 +1,7 @@
>   #include <stdio.h>
>   #include <errno.h>
> +#include <stdlib.h>
> +#include <unistd.h>
>   
>   #include "nvme.h"
>   #include "nvme-print.h"
> @@ -127,6 +129,88 @@ static int lnvm_id_ns(int argc, char **argv, struct command *cmd, struct plugin
>   	return lnvm_do_id_ns(fd, cfg.namespace_id, flags);
>   }
>   
> +static int lnvm_chunk_log(int argc, char **argv, struct command *cmd, struct plugin *plugin)
> +{
> +	const char *desc = "Retrieve the chunk information log for the "\
> +		"specified given LightNVM device, returns in either "\
> +		"human-readable or binary format.\n"\
> +		"This will request Geometry first to get the "\
> +		"num_grp,num_pu,num_chk first to figure out the total size "\
> +		"of the log pages."\
> +		;
> +	const char *output_format = "Output format: normal|binary";
> +	const char *human_readable = "Print normal in readable format";
> +	int err, fmt, fd;
> +	struct nvme_nvm_id20 geo;
> +	struct nvme_nvm_chunk_desc *chunk_log;
> +	__u32 nsid;
> +	__u32 data_len;
> +	unsigned int flags = 0;
> +
> +	struct config {
> +		char *output_format;
> +		int human_readable;
> +	};
> +
> +	struct config cfg = {
> +		.output_format = "normal",
> +	};
> +
> +	const struct argconfig_commandline_options command_line_options[] = {
> +		{"output-format", 'o', "FMT", CFG_STRING, &cfg.output_format, required_argument, output_format},
> +		{"human-readable",'H', "",    CFG_NONE,   &cfg.human_readable,no_argument,       human_readable},
> +		{NULL}
> +	};
> +
> +	fd = parse_and_open(argc, argv, desc, command_line_options, &cfg,
> +				sizeof(cfg));
> +	if (fd < 0) {
> +		err = fd;
> +		goto ret;
> +	}
> +
> +	fmt = validate_output_format(cfg.output_format);
> +	if (fmt < 0) {
> +		err = fmt;
> +		goto close;
> +	}
> +
> +	if (fmt == BINARY)
> +		flags |= RAW;
> +	else if (cfg.human_readable)
> +		flags |= HUMAN;
> +
> +	nsid = nvme_get_nsid(fd);
> +
> +	/*
> +	 * It needs to figure out how many bytes will be requested by this
> +	 * subcommand by the (num_grp * num_pu * num_chk) from the Geometry.
> +	 */
> +	err = lnvm_get_identity(fd, nsid, (struct nvme_nvm_id *) &geo);
> +	if (err)
> +		goto close;
> +
> +	data_len = (geo.num_grp * geo.num_pu * geo.num_chk) *
> +			sizeof(struct nvme_nvm_chunk_desc);
> +	chunk_log = malloc(data_len);
> +	if (!chunk_log) {
> +		fprintf(stderr, "cound not alloc for chunk log %dbytes\n",
> +				data_len);
> +		err = -ENOMEM;
> +		goto close;
> +	}
> +
> +	err = lnvm_do_chunk_log(fd, nsid, data_len, chunk_log, flags);
> +	if (err)
> +		fprintf(stderr, "get log page for chunk information failed\n");
> +
> +	free(chunk_log);
> +close:
> +	close(fd);
> +ret:
> +	return err;
> +}
> +
>   static int lnvm_create_tgt(int argc, char **argv, struct command *cmd, struct plugin *plugin)
>   {
>   	const char *desc = "Instantiate a target on top of a LightNVM enabled device.";
> diff --git a/plugins/lnvm/lnvm-nvme.h b/plugins/lnvm/lnvm-nvme.h
> index 3d5cbc5..f091f7b 100644
> --- a/plugins/lnvm/lnvm-nvme.h
> +++ b/plugins/lnvm/lnvm-nvme.h
> @@ -12,6 +12,7 @@ PLUGIN(NAME("lnvm", "LightNVM specific extensions"),
>   		ENTRY("list", "List available LightNVM devices", lnvm_list)
>   		ENTRY("info", "List general information and available target engines", lnvm_info)
>   		ENTRY("id-ns", "List geometry for LightNVM device", lnvm_id_ns)
> +		ENTRY("chunk-log", "Chunk information by Get Log Page", lnvm_chunk_log)

Chunk Information Log Page ?

>   		ENTRY("init", "Initialize media manager on LightNVM device", lnvm_init)
>   		ENTRY("create", "Create target on top of a LightNVM device", lnvm_create_tgt)
>   		ENTRY("remove", "Remove target from device", lnvm_remove_tgt)

Hi Minwoo,

Could you squash patch 2, 3 and 4 together (4 being the main patch) - 
They belong together to implement one feature.

As a side-note, we have the same command for ZNS (that will be pushed 
when the ZNS TP is ratified) - In that, we've also added support for 
supplying start lba and number of chunks (zones) to return. Could you 
add that as well to this? Then there is coherency between the two?

-Matias