[PATCH 3/4] nvme-fabrics: add tp8010 support
Sagi Grimberg
sagi at grimberg.me
Thu Jan 27 05:12:05 PST 2022
On 1/27/22 11:30, Hannes Reinecke wrote:
> On 1/25/22 15:59, Martin Belanger wrote:
>> From: Martin Belanger <martin.belanger at dell.com>
>>
>> TP8010 introduces Central Discovery Controllers (CDC) and the
>> Discovery Information Management (DIM) PDU, which is used to
>> perform explicit registration with Discovery Controllers.
>>
>> This patch defines the DIM PDU and adds logic to perform explicit
>> registration with DCs when registration has been requested by the
>> user.
>>
>> Signed-off-by: Martin Belanger <martin.belanger at dell.com>
>> ---
>> drivers/nvme/host/fabrics.c | 164 +++++++++++++++++++++++
>> drivers/nvme/host/fabrics.h | 9 ++
>> drivers/nvme/host/tcp.c | 51 +++++++-
>> include/linux/nvme.h | 255 ++++++++++++++++++++++++++++++++++--
>> 4 files changed, 467 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/nvme/host/fabrics.c b/drivers/nvme/host/fabrics.c
>> index 040a6cce6afa..e6fc2f85b670 100644
>> --- a/drivers/nvme/host/fabrics.c
>> +++ b/drivers/nvme/host/fabrics.c
>> @@ -10,6 +10,7 @@
>> #include <linux/mutex.h>
>> #include <linux/parser.h>
>> #include <linux/seq_file.h>
>> +#include <linux/utsname.h>
>> #include "nvme.h"
>> #include "fabrics.h"
>> @@ -526,6 +527,165 @@ static struct nvmf_transport_ops
>> *nvmf_lookup_transport(
>> return NULL;
>> }
>> +/**
>> + * nvmf_get_tel() - Calculate the amount of memory needed for a
>> Discovery
>> + * Information Entry. Each Entry must contain at a minimum an Extended
>> + * Attribute for the HostID. The Entry may optionally contain an
>> Extended
>> + * Attribute for the Symbolic Name.
>> + *
>> + * @hostsymname - Symbolic name (may be NULL)
>> + *
>> + * Return Total Entry Length
>> + */
>> +static u32 nvmf_get_tel(const char *hostsymname)
>> +{
>> + u32 tel = SIZEOF_EXT_DIE_WO_EXAT;
>> + u16 len;
>> +
>> + /* Host ID is mandatory */
>> + tel += exat_size(sizeof(uuid_t));
>> +
>> + /* Symbolic name is optional */
>> + len = hostsymname ? strlen(hostsymname) : 0;
>> + if (len)
>> + tel += exat_size(len);
>> +
>> + return tel;
>> +}
>> +
>> +/**
>> + * nvmf_fill_die() - Fill the Discovery Information Entry pointed to by
>> + * @die.
>> + *
>> + * @die - Pointer to Discovery Information Entry to be filled
>> + * @tel - Length of the DIE
>> + * @trtype - Transport type
>> + * @adrfam - Address family
>> + * @reg_addr - Address to register. Setting this to an empty string
>> tells
>> + * the DC to infer address from the source address of the socket.
>> + * @nqn - Host NQN
>> + * @hostid - Host ID
>> + * @hostsymname - Host symbolic name
>> + * @tsas - Transport Specific Address Subtype for the address being
>> + * registered.
>> + */
>> +static void nvmf_fill_die(struct nvmf_ext_die *die,
>> + u32 tel,
>> + u8 trtype,
>> + u8 adrfam,
>> + const char *reg_addr,
>> + struct nvmf_host *host,
>> + union nvmf_tsas *tsas)
>> +{
>> + u16 numexat = 0;
>> + size_t symname_len;
>> + struct nvmf_ext_attr *exat;
>> +
>> + die->tel = cpu_to_le32(tel);
>> + die->trtype = trtype;
>> + die->adrfam = adrfam;
>> +
>> + strncpy(die->nqn, host->nqn, sizeof(die->nqn));
>> + strncpy(die->traddr, reg_addr, sizeof(die->traddr));
>> + memcpy(&die->tsas, tsas, sizeof(die->tsas));
>> +
>> + /* Extended Attribute for the HostID (mandatory) */
>> + numexat++;
>> + exat = &die->exat;
>> + exat->type = cpu_to_le16(NVME_EXATTYPE_HOSTID);
>> + exat->len = cpu_to_le16(exat_len(sizeof(host->id)));
>> + uuid_copy((uuid_t *)exat->val, &host->id);
>> +
>> + /* Extended Attribute for the Symbolic Name (optional) */
>> + symname_len = strlen(host->symname);
>> + if (symname_len) {
>> + u16 exatlen = exat_len(symname_len);
>> +
>> + numexat++;
>> + exat = exat_ptr_next(exat);
>> + exat->type = cpu_to_le16(NVME_EXATTYPE_SYMNAME);
>> + exat->len = cpu_to_le16(exatlen);
>> + memcpy(exat->val, host->symname, symname_len);
>> + /* Per Base specs, ASCII strings must be padded with spaces */
>> + memset(&exat->val[symname_len], ' ', exatlen - symname_len);
>> + }
>> +
>> + die->numexat = cpu_to_le16(numexat);
>> +}
>> +
>> +/**
>> + * nvmf_disc_info_mgmt() - Perform explicit registration,
>> deregistration,
>> + * or registration-update (specified by @tas) by sending a Discovery
>> + * Information Management (DIM) command to the Discovery Controller
>> (DC).
>> + *
>> + * @ctrl: Host NVMe controller instance maintaining the admin queue
>> used to
>> + * submit the DIM command to the DC.
>> + * @tas: Task field of the Command Dword 10 (cdw10). Indicates
>> whether to
>> + * perform a Registration, Deregistration, or Registration-update.
>> + * @trtype: Transport type (e.g. NVMF_TRTYPE_TCP)
>> + * @adrfam: Address family (e.g. NVMF_ADDR_FAMILY_IP6)
>> + * @reg_addr - Address to register. Setting this to an empty string
>> tells
>> + * the DC to infer address from the source address of the socket.
>> + * @tsas - Transport Specific Address Subtype for the address being
>> + * registered.
>> + *
>> + * Return: 0: success,
>> + * > 0: NVMe error status code,
>> + * < 0: Linux errno error code
>> + */
>> +int nvmf_disc_info_mgmt(struct nvme_ctrl *ctrl,
>> + enum nvmf_dim_tas tas,
>> + u8 trtype,
>> + u8 adrfam,
>> + const char *reg_addr,
>> + union nvmf_tsas *tsas)
>> +{
>> + int ret;
>> + u32 tdl; /* Total Data Length */
>> + u32 tel; /* Total Entry Length */
>> + struct nvmf_dim_data *dim; /* Discovery Information Management */
>> + struct nvmf_ext_die *die; /* Discovery Information Entry */
>> + struct nvme_command cmd = {};
>> + union nvme_result result;
>> +
>> + /* Register 1 Discovery Information Entry (DIE) of size TEL */
>> + tel = nvmf_get_tel(ctrl->opts->host->symname);
>> + tdl = SIZEOF_DIM_WO_DIE + tel;
>> +
>> + dim = kzalloc(tdl, GFP_KERNEL);
>> + if (!dim)
>> + return -ENOMEM;
>> +
>> + cmd.dim.opcode = nvme_admin_dim;
>> + cmd.dim.cdw10 = cpu_to_le32(tas);
>> +
>> + dim->tdl = cpu_to_le32(tdl);
>> + dim->nument = cpu_to_le64(1); /* only 1 DIE to register */
>> + dim->entfmt = cpu_to_le16(NVME_ENTFMT_EXTENDED);
>> + dim->etype = cpu_to_le16(NVME_REGISTRATION_HOST);
>> + dim->ektype = cpu_to_le16(0x5F); /* must be 0x5F per specs */
>> +
>> + strncpy(dim->eid, ctrl->opts->host->nqn, sizeof(dim->eid));
>> + strncpy(dim->ename, utsname()->nodename, sizeof(dim->ename));
>> + strncpy(dim->ever, utsname()->release, sizeof(dim->ever));
>> +
>> + die = &dim->die.extended;
>> + nvmf_fill_die(die, tel, trtype, adrfam, reg_addr,
>> + ctrl->opts->host, tsas);
>> +
>> + ret = __nvme_submit_sync_cmd(ctrl->fabrics_q, &cmd, &result,
>> + dim, tdl, 0, NVME_QID_ANY, 1, 0);
>> + if (unlikely(ret)) {
>> + dev_err(ctrl->device, "DIM error Result:0x%04X Status:0x%04X\n",
>> + le32_to_cpu(result.u32), ret);
>> + }
>> +
>> + kfree(dim);
>> +
>> + return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(nvmf_disc_info_mgmt);
>> +
>> static const match_table_t opt_tokens = {
>> { NVMF_OPT_TRANSPORT, "transport=%s" },
>> { NVMF_OPT_TRADDR, "traddr=%s" },
>> @@ -550,6 +710,7 @@ static const match_table_t opt_tokens = {
>> { NVMF_OPT_TOS, "tos=%d" },
>> { NVMF_OPT_FAIL_FAST_TMO, "fast_io_fail_tmo=%d" },
>> { NVMF_OPT_DISCOVERY, "discovery" },
>> + { NVMF_OPT_REGISTER, "register" },
>> { NVMF_OPT_ERR, NULL }
>> };
>> @@ -831,6 +992,9 @@ static int nvmf_parse_options(struct
>> nvmf_ctrl_options *opts,
>> case NVMF_OPT_DISCOVERY:
>> opts->discovery_nqn = true;
>> break;
>> + case NVMF_OPT_REGISTER:
>> + opts->explicit_registration = true;
>> + break;
>> case NVMF_OPT_SYMNAME:
>> hostsymname = match_strdup(args);
>> if (!hostsymname) {
>> diff --git a/drivers/nvme/host/fabrics.h b/drivers/nvme/host/fabrics.h
>> index 494e6dbe233a..77f5768f8ff4 100644
>> --- a/drivers/nvme/host/fabrics.h
>> +++ b/drivers/nvme/host/fabrics.h
>> @@ -70,6 +70,7 @@ enum {
>> NVMF_OPT_HOST_IFACE = 1 << 21,
>> NVMF_OPT_DISCOVERY = 1 << 22,
>> NVMF_OPT_SYMNAME = 1 << 23,
>> + NVMF_OPT_REGISTER = 1 << 24,
>> };
>> /**
>> @@ -106,6 +107,7 @@ enum {
>> * @nr_poll_queues: number of queues for polling I/O
>> * @tos: type of service
>> * @fast_io_fail_tmo: Fast I/O fail timeout in seconds
>> + * @explicit_registration: Explicit Registration with DC using the
>> DIM PDU
>> */
>> struct nvmf_ctrl_options {
>> unsigned mask;
>> @@ -130,6 +132,7 @@ struct nvmf_ctrl_options {
>> unsigned int nr_poll_queues;
>> int tos;
>> int fast_io_fail_tmo;
>> + bool explicit_registration;
>> };
>> /*
>> @@ -200,5 +203,11 @@ int nvmf_get_address(struct nvme_ctrl *ctrl, char
>> *buf, int size);
>> bool nvmf_should_reconnect(struct nvme_ctrl *ctrl);
>> bool nvmf_ip_options_match(struct nvme_ctrl *ctrl,
>> struct nvmf_ctrl_options *opts);
>> +int nvmf_disc_info_mgmt(struct nvme_ctrl *ctrl,
>> + enum nvmf_dim_tas tas,
>> + u8 trtype,
>> + u8 adrfam,
>> + const char *reg_addr,
>> + union nvmf_tsas *tsas);
>> #endif /* _NVME_FABRICS_H */
>> diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
>> index 4ceb28675fdf..970b7df574a4 100644
>> --- a/drivers/nvme/host/tcp.c
>> +++ b/drivers/nvme/host/tcp.c
>> @@ -1993,6 +1993,40 @@ static void nvme_tcp_reconnect_or_remove(struct
>> nvme_ctrl *ctrl)
>> }
>> }
>> +/**
>> + * nvme_get_adrfam() - Get address family for the address we're
>> registering
>> + * with the DC. We retrieve this info from the socket itself. If we
>> can't
>> + * get the source address from the socket, then we'll infer the address
>> + * family from the address of the DC since the DC address has the same
>> + * address family.
>> + *
>> + * @ctrl: Host NVMe controller instance maintaining the admin queue
>> used to
>> + * submit the DIM command to the DC.
>> + *
>> + * Return: The address family of the source address associated with the
>> + * socket connected to the DC.
>> + */
>> +static u8 nvme_get_adrfam(struct nvme_ctrl *ctrl)
>> +{
>> + u8 adrfam = NVMF_ADDR_FAMILY_IP4;
>> + struct sockaddr_storage sas;
>> + struct sockaddr *sa = (struct sockaddr *)&sas;
>> + struct nvme_tcp_queue *queue = &to_tcp_ctrl(ctrl)->queues[0];
>> +
>> + if (kernel_getsockname(queue->sock, sa) == 0) {
>> + if (sa->sa_family == AF_INET6)
>> + adrfam = NVMF_ADDR_FAMILY_IP6;
>> + } else {
>> + unsigned char buf[sizeof(struct in6_addr)];
>> +
>> + if (in6_pton(ctrl->opts->traddr,
>> + strlen(ctrl->opts->traddr), buf, -1, NULL) > 0)
>> + adrfam = NVMF_ADDR_FAMILY_IP6;
>> + }
>> +
>> + return adrfam;
>> +}
>> +
>> static int nvme_tcp_setup_ctrl(struct nvme_ctrl *ctrl, bool new)
>> {
>> struct nvmf_ctrl_options *opts = ctrl->opts;
>> @@ -2045,6 +2079,20 @@ static int nvme_tcp_setup_ctrl(struct nvme_ctrl
>> *ctrl, bool new)
>> goto destroy_io;
>> }
>> + if (ctrl->opts->explicit_registration &&
>> ++ ((ctrl->dctype == NVME_DCTYPE_DDC) ||
>> + (ctrl->dctype == NVME_DCTYPE_CDC))) {
>> + /* We're registering our source address with the DC. To do
>> + * that, we can simply send an empty string. This tells the DC
>> + * to retrieve the source address from the socket and use that
>> + * as the registration address.
>> + */
>> + union nvmf_tsas tsas = {.tcp.sectype = NVMF_TCP_SECTYPE_NONE};
>> +
>> + nvmf_disc_info_mgmt(ctrl, NVME_TAS_REGISTER, NVMF_TRTYPE_TCP,
>> + nvme_get_adrfam(ctrl), "", &tsas);
>> + }
>> +
>> nvme_start_ctrl(ctrl);
>> return 0;
>> @@ -2613,7 +2661,8 @@ static struct nvmf_transport_ops
>> nvme_tcp_transport = {
>> NVMF_OPT_HOST_TRADDR | NVMF_OPT_CTRL_LOSS_TMO |
>> NVMF_OPT_HDR_DIGEST | NVMF_OPT_DATA_DIGEST |
>> NVMF_OPT_NR_WRITE_QUEUES | NVMF_OPT_NR_POLL_QUEUES |
>> - NVMF_OPT_TOS | NVMF_OPT_HOST_IFACE,
>> + NVMF_OPT_TOS | NVMF_OPT_HOST_IFACE |
>> + NVMF_OPT_REGISTER,
>> .create_ctrl = nvme_tcp_create_ctrl,
>> };
>> diff --git a/include/linux/nvme.h b/include/linux/nvme.h
>> index 3b47951342f4..891615876cfa 100644
>> --- a/include/linux/nvme.h
>> +++ b/include/linux/nvme.h
>> @@ -9,6 +9,7 @@
>> #include <linux/types.h>
>> #include <linux/uuid.h>
>> +#include <linux/kernel.h>
>> /* NQN names in commands fields specified one size */
>> #define NVMF_NQN_FIELD_LEN 256
>> @@ -102,6 +103,16 @@ enum {
>> NVMF_RDMA_CMS_RDMA_CM = 1, /* Sockets based endpoint
>> addressing */
>> };
>> +/**
>> + * enum -
>> + * @NVMF_TCP_SECTYPE_NONE: No Security
>> + * @NVMF_TCP_SECTYPE_TLS: Transport Layer Security
>> + */
>> +enum {
>> + NVMF_TCP_SECTYPE_NONE = 0,
>> + NVMF_TCP_SECTYPE_TLS = 1,
>> +};
>> +
>> #define NVME_AQ_DEPTH 32
>> #define NVME_NR_AEN_COMMANDS 1
>> #define NVME_AQ_BLK_MQ_DEPTH (NVME_AQ_DEPTH - NVME_NR_AEN_COMMANDS)
>> @@ -1036,6 +1047,7 @@ enum nvme_admin_opcode {
>> nvme_admin_sanitize_nvm = 0x84,
>> nvme_admin_get_lba_status = 0x86,
>> nvme_admin_vendor_start = 0xC0,
>> + nvme_admin_dim = 0x21,
>> };
>> #define nvme_admin_opcode_name(opcode) { opcode, #opcode }
>> @@ -1316,6 +1328,29 @@ struct nvmf_common_command {
>> __u8 ts[24];
>> };
>> +/**
>> + * union nvmf_tsas - Transport Specific Address Subtype
>> + * @qptype: Queue Pair Service Type (NVMF_RDMA_QPTYPE_CONNECTED,
>> NVMF_RDMA_QPTYPE_DATAGRAM)
>> + * @prtype: Provider Type (see enum nvme_rdma_prtype)
>> + * @cma: Connection Management Service (NVMF_RDMA_CMS_RDMA_CM)
>> + * @pkey: Partition Key
>> + * @sectype: Security Type (NVMF_TCP_SECTYPE_NONE, NVMF_TCP_SECTYPE_TLS)
>> + */
>> +union nvmf_tsas {
>> + char common[NVMF_TSAS_SIZE];
>> + struct rdma {
>> + __u8 qptype;
>> + __u8 prtype;
>> + __u8 cms;
>> + __u8 rsvd3[5];
>> + __u16 pkey;
>> + __u8 rsvd10[246];
>> + } rdma;
>> + struct tcp {
>> + __u8 sectype;
>> + } tcp;
>> +};
>> +
>> /*
>> * The legal cntlid range a NVMe Target will provide.
>> * Note that cntlid of value 0 is considered illegal in the fabrics
>> world.
>> @@ -1349,17 +1384,7 @@ struct nvmf_disc_rsp_page_entry {
>> __u8 resv64[192];
>> char subnqn[NVMF_NQN_FIELD_LEN];
>> char traddr[NVMF_TRADDR_SIZE];
>> - union tsas {
>> - char common[NVMF_TSAS_SIZE];
>> - struct rdma {
>> - __u8 qptype;
>> - __u8 prtype;
>> - __u8 cms;
>> - __u8 resv3[5];
>> - __u16 pkey;
>> - __u8 resv10[246];
>> - } rdma;
>> - } tsas;
>> + union nvmf_tsas tsas;
>> };
>> /* Discovery log page header */
>> @@ -1447,6 +1472,213 @@ struct streams_directive_params {
>> __u8 rsvd2[6];
>> };
>> +/**
>> + * Discovery Information Management (DIM) command. This is sent by a
>> + * host to the Central Discovery Controller (CDC) to perform
>> + * explicit registration.
>> + */
>> +enum nvmf_dim_tas {
>> + NVME_TAS_REGISTER = 0x00,
>> + NVME_TAS_DEREGISTER = 0x01,
>> + NVME_TAS_UPDATE = 0x02,
>> +};
>> +
>> +struct nvmf_dim_command {
>> + __u8 opcode; /* nvme_admin_dim */
>> + __u8 flags;
>> + __u16 command_id;
>> + __le32 nsid;
>> + __u64 rsvd2[2];
>> + union nvme_data_ptr dptr;
>> + __le32 cdw10; /* enum nvmf_dim_tas */
>> + __le32 cdw11;
>> + __le32 cdw12;
>> + __le32 cdw13;
>> + __le32 cdw14;
>> + __le32 cdw15;
>> +};
>> +
>> +#define NVMF_ENAME_LEN 256
>> +#define NVMF_EVER_LEN 64
>> +
>> +enum nvmf_dim_entfmt {
>> + NVME_ENTFMT_BASIC = 0x01,
>> + NVME_ENTFMT_EXTENDED = 0x02,
>> +};
>> +
>> +enum nvmf_dim_etype {
>> + NVME_REGISTRATION_HOST = 0x01,
>> + NVME_REGISTRATION_DDC = 0x02,
>> + NVME_REGISTRATION_CDC = 0x03,
>> +};
>> +
>> +enum nvmf_exattype {
>> + NVME_EXATTYPE_HOSTID = 0x01, /* Host Identifier */
>> + NVME_EXATTYPE_SYMNAME = 0x02, /* Symbolic Name */
>> +};
>> +
>> +/**
>> + * struct nvmf_ext_attr - Extended Attribute (EXAT)
>> + *
>> + * Bytes Description
>> + * @type 01:00 Extended Attribute Type (EXATTYPE) - enum
>> nvmf_exattype
>> + * @len 03:02 Extended Attribute Length (EXATLEN)
>> + * @val (EXATLEN-1) Extended Attribute Value (EXATVAL) - size allocated
>> + * +4:04 for array must be a multiple of 4 bytes
>> + */
>> +struct nvmf_ext_attr {
>> + __le16 type;
>> + __le16 len;
>> + __u8 val[];
>> +};
>> +#define SIZEOF_EXT_EXAT_WO_VAL offsetof(struct nvmf_ext_attr, val)
>> +
>> +/**
>> + * struct nvmf_ext_die - Extended Discovery Information Entry (DIE)
>> + *
>> + * Bytes Description
>> + * @trtype 00 Transport Type (enum nvme_trtype)
>> + * @adrfam 01 Address Family (enum nvmf_addr_familiy)
>> + * @subtype 02 Subsystem Type (enum nvme_subsys_type)
>> + * @treq 03 Transport Requirements (enum nvmf_treq)
>> + * @portid 05:04 Port ID
>> + * @cntlid 07:06 Controller ID
>> + * @asqsz 09:08 Admin Max SQ Size
>> + * 31:10 Reserved
>> + * @trsvcid 63:32 Transport Service Identifier
>> + * 255:64 Reserved
>> + * @nqn 511:256 NVM Qualified Name
>> + * @traddr 767:512 Transport Address
>> + * @tsas 1023:768 Transport Specific Address Subtype
>> + * @tel 1027:1024 Total Entry Length
>> + * @numexat 1029:1028 Number of Extended Attributes
>> + * 1031:1030 Reserved
>> + * @exat[0] ((EXATLEN-1)+ Extented Attributes 0 (see @numexat)
>> + * 4)+1032:1032 Cannot access as an array because each
>> EXAT
>> + * entry has an undetermined size.
>> + * @exat[N] TEL-1:TEL- Extented Attributes N (w/ N = NUMEXAT-1)
>> + * (EXATLEN+4)
>> + */
>> +struct nvmf_ext_die {
>> + __u8 trtype;
>> + __u8 adrfam;
>> + __u8 subtype;
>> + __u8 treq;
>> + __le16 portid;
>> + __le16 cntlid;
>> + __le16 asqsz;
>> + __u8 resv10[22];
>> + char trsvcid[NVMF_TRSVCID_SIZE];
>> + __u8 resv64[192];
>> + char nqn[NVMF_NQN_FIELD_LEN];
>> + char traddr[NVMF_TRADDR_SIZE];
>> + union nvmf_tsas tsas;
>> + __le32 tel;
>> + __le16 numexat;
>> + __u16 resv1030;
>> + struct nvmf_ext_attr exat;
>> +};
>> +#define SIZEOF_EXT_DIE_WO_EXAT offsetof(struct nvmf_ext_die, exat)
>> +
>> +/**
>> + * union nvmf_die - Discovery Information Entry (DIE)
>> + *
>> + * Depending on the ENTFMT specified in the DIM, DIEs can be entered
>> with
>> + * the Basic or Extended formats. For Basic format, each entry has a
>> fixed
>> + * length. Therefore, the "basic" field defined below can be accessed
>> as a
>> + * C array. For the Extended format, however, each entry is of variable
>> + * length (TEL). Therefore, the "extended" field defined below cannot be
>> + * accessed as a C array. Instead, the "extended" field is akin to a
>> + * linked-list, where one can "walk" through the list. To move to the
>> next
>> + * entry, one simply adds the current entry's length (TEL) to the "walk"
>> + * pointer. The number of entries in the list is specified by NUMENT.
>> + * Although extended entries are of a variable lengths (TEL), TEL is
>> + * always a multiple of 4 bytes.
>> + */
>> +union nvmf_die {
>> + struct nvmf_disc_rsp_page_entry basic[0];
>> + struct nvmf_ext_die extended;
>> +};
>> +
>> +/**
>> + * struct nvmf_dim_data - Discovery Information Management (DIM) - Data
>> + *
>> + * Bytes Description
>> + * @tdl 03:00 Total Data Length
>> + * 07:04 Reserved
>> + * @nument 15:08 Number of entries
>> + * @entfmt 17:16 Entry Format (enum nvmf_dim_entfmt)
>> + * @etype 19:18 Entity Type (enum nvmf_dim_etype)
>> + * @portlcL 20 Port Local
>> + * 21 Reserved
>> + * @ektype 23:22 Entry Key Type
>> + * @eid 279:24 Entity Identifier (e.g. Host NQN)
>> + * @ename 535:280 Entity Name (e.g. hostname)
>> + * @ever 599:536 Entity Version (e.g. OS Name/Version)
>> + * 1023:600 Reserved
>> + * @die TDL-1:1024 Discovery Information Entry (see @nument
>> above)
>> + */
>> +struct nvmf_dim_data {
>> + __le32 tdl;
>> + __u32 rsvd4;
>> + __le64 nument;
>> + __le16 entfmt;
>> + __le16 etype;
>> + __u8 portlcl;
>> + __u8 rsvd21;
>> + __le16 ektype;
>> + char eid[NVMF_NQN_FIELD_LEN];
>> + char ename[NVMF_ENAME_LEN];
>> + char ever[NVMF_EVER_LEN];
>> + __u8 rsvd600[424];
>> + union nvmf_die die;
>> +};
>> +#define SIZEOF_DIM_WO_DIE offsetof(struct nvmf_dim_data, die)
>> +
>> +/**
>> + * exat_len() - Return the size in bytes, rounded to a multiple of 4
>> ((i.e.
>> + * size of u32), of the buffer needed to hold the exat value of
>> + * size @val_len.
>> + */
>> +static inline u16 exat_len(size_t val_len)
>> +{
>> + return (u16)round_up(val_len, sizeof(u32));
>> +}
>> +
>> +/**
>> + * exat_size - return the size of the "struct nvmf_ext_attr"
>> + * needed to hold a value of size @val_len.
>> + *
>> + * @val_len: This is the length of the data to be copied to the "val"
>> + * field of a "struct nvmf_ext_attr".
>> + *
>> + * @return The size in bytes, rounded to a multiple of 4 (i.e. size of
>> + * u32), of the "struct nvmf_ext_attr" required to hold a
>> string of
>> + * length @val_len.
>> + */
>> +static inline u16 exat_size(size_t val_len)
>> +{
>> + return (u16)(SIZEOF_EXT_EXAT_WO_VAL + exat_len(val_len));
>> +}
>> +
>> +/**
>> + * exat_ptr_next - Increment @p to the next element in the array.
>> Extended
>> + * attributes are saved to an array of "struct nvmf_ext_attr" where
>> each
>> + * element of the array is of variable size. In order to move to
>> the next
>> + * element in the array one must increment the pointer to the current
>> + * element (@p) by the size of the current element.
>> + *
>> + * @p: Pointer to an element of an array of "struct nvmf_ext_attr".
>> + *
>> + * @return Pointer to the next element in the array.
>> + */
>> +static inline struct nvmf_ext_attr *exat_ptr_next(struct
>> nvmf_ext_attr *p)
>> +{
>> + return (struct nvmf_ext_attr *)
>> + ((uintptr_t)p + (ptrdiff_t)exat_size(le16_to_cpu(p->len)));
>> +}
>> +
>> +
>> struct nvme_command {
>> union {
>> struct nvme_common_command common;
>> @@ -1470,6 +1702,7 @@ struct nvme_command {
>> struct nvmf_property_get_command prop_get;
>> struct nvme_dbbuf dbbuf;
>> struct nvme_directive_cmd directive;
>> + struct nvmf_dim_command dim;
>> };
>> };
> I'd rather like to have the TLS bits in a separate patch; they are not
> strictly related to this issue.
>
> And I have a rather general issue with this: Is it required to issue an
> explicit registration directly after sending the 'connect' command?
> IE do we need to have it as part of the 'connect' routine?
>
> Thing is, the linux 'connect' routine is doing several things in one go
> (like establishing a transport association for the admin queue, send the
> 'connect' command for the admin queue, create transport associations for
> I/O queues and send 'connect' commands on all I/O queues, _and_ possibly
> do authentication, too).
> If we now start overloading it with yet more functionality it becomes
> extremely hard to cleanup after an error, and that doesn't even mention
> the non-existing error reporting to userspace.
>
> Wouldn't it make more sense to delegate explicit registration to
> userspace (ie libnvme/nvme-cli), and leave the kernel out of it?
It would. There is no reason what-so-ever to place all this register
stuff needs to live in the kernel. We have a way to passthru commands so
it can and should move to userspace.
More information about the Linux-nvme
mailing list