nvme-cli: extend ctrl_list_item for connect attributes

In preparation for searching controllers to match with connect args:

Extend the ctrl_list_item with elements that can be compared against
connect arguments. Extend the get_nvme_ctrl_info() routine to set
the fields.

subsysnqn was added as the ctrl_list_item may now be used outside of
a subsystem listing.

traddr, trsvid, and host_traddr are added. Their values come from
the address attribute.  A new parsing routine was added that extracts
the values from the address string.

The new parsing routine and supporting field names strings are
declared as a global interface as a subsequent patch will call it
from the fabrics routines.

Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.com>

diff --git a/nvme.c b/nvme.c
index 30b0cc50363e92eb28e05c8bb43a9c21bfa54c1c..1c5126150659fed0b33a626f6f84b3ba0037a5e2 100644 (file)
--- a/nvme.c
+++ b/nvme.c
@@ -1542,6 +1542,64 @@ static void free_ctrl_list_item(struct ctrl_list_item *ctrls)
        free(ctrls->address);
        free(ctrls->state);
        free(ctrls->ana_state);
+       free(ctrls->subsysnqn);
+       free(ctrls->traddr);
+       free(ctrls->trsvcid);
+       free(ctrls->host_traddr);
+}
+
+static const char delim_space  = ' ';
+const char *conarg_traddr = "traddr";
+const char *conarg_trsvcid = "trsvcid";
+const char *conarg_host_traddr = "host_traddr";
+
+/*
+ * parse strings with connect arguments to find a particular field.
+ * If field found, return string containing field value. If field
+ * not found, return an empty string.
+ */
+char *__parse_connect_arg(char *conargs, const char delim, const char *fieldnm)
+{
+       char *s, *e;
+       size_t cnt;
+
+       /*
+        * There are field name overlaps: traddr and host_traddr.
+        * By chance, both connect arg strings are set up to
+        * have traddr field followed by host_traddr field. Thus field
+        * name matching doesn't overlap in the searches. Technically,
+        * as is, the loop and delimiter checking isn't necessary.
+        * However, better to be prepared.
+        */
+       do {
+               s = strstr(conargs, fieldnm);
+               if (!s)
+                       goto empty_field;
+               /* validate prior character is delimiter */
+               if (s == conargs || *(s - 1) == delim) {
+                       /* match requires next character to be assignment */
+                       s += strlen(fieldnm);
+                       if (*s == '=')
+                               /* match */
+                               break;
+               }
+               /* field overlap: seek to delimiter and keep looking */
+               conargs = strchr(s, delim);
+               if (!conargs)
+                       goto empty_field;
+               conargs++;      /* skip delimiter */
+       } while (1);
+       s++;            /* skip assignment character */
+       e = strchr(s, delim);
+       if (e)
+               cnt = e - s;
+       else
+               cnt = strlen(s);
+
+       return strndup(s, cnt);
+
+empty_field:
+       return strdup("\0");
 }
 
 static int get_nvme_ctrl_info(char *name, char *path,
@@ -1577,6 +1635,20 @@ static int get_nvme_ctrl_info(char *name, char *path,
        if (nsid != NVME_NSID_ALL)
                ctrl->ana_state = get_nvme_ctrl_path_ana_state(ctrl_path, nsid);
 
+       ctrl->subsysnqn = get_nvme_ctrl_attr(ctrl_path, "subsysnqn");
+       if (!ctrl->subsysnqn) {
+               fprintf(stderr, "%s: failed to get controller subsysnqn.\n",
+                       ctrl->name);
+               goto free_ctrl_items;
+       }
+
+       ctrl->traddr = __parse_connect_arg(ctrl->address, delim_space,
+                                       conarg_traddr);
+       ctrl->trsvcid = __parse_connect_arg(ctrl->address, delim_space,
+                                       conarg_trsvcid);
+       ctrl->host_traddr = __parse_connect_arg(ctrl->address, delim_space,
+                                       conarg_host_traddr);
+
        return 0;       /* success */
 
 free_ctrl_items:

diff --git a/nvme.h b/nvme.h
index 3409515cb9fb5ae6104841961219c05b25cc4230..470f702641f45c64c73e0891d9761b51c0d8cf97 100644 (file)
--- a/nvme.h
+++ b/nvme.h
@@ -160,6 +160,10 @@ struct ctrl_list_item {
        char *transport;
        char *state;
        char *ana_state;
+       char *subsysnqn;
+       char *traddr;
+       char *trsvcid;
+       char *host_traddr;
 };
 
 struct subsys_list_item {
@@ -175,6 +179,12 @@ enum {
        BINARY,
 };
 
+char *__parse_connect_arg(char *conargs, const char delim, const char *fieldnm);
+
+extern const char *conarg_traddr;
+extern const char *conarg_trsvcid;
+extern const char *conarg_host_traddr;
+
 void register_extension(struct plugin *plugin);
 
 #include "argconfig.h"