nvme_ioctl_submit_io issue

[Zakaria Abushima (zabushima)]

Hi Guys,

I try to write to the name space using following application,

               static const char *perrstr;

               char data[] = "Zakaria";
               struct nvme_passthru_cmd write, compare;
               struct nvme_user_io io;

               int fd, err;

               perrstr = argv[1];

               fd = open(argv[1], O_RDWR);
               if (fd < 0)
                              goto perror;

               io.opcode = nvme_cmd_write;
               io.flags = 0;
               io.control = 0;
               io.metadata = (unsigned long)0;
               io.addr = (unsigned long)data;
               io.slba = 0;
               io.nblocks = 7;
               io.dsmgmt = 0;
               io.reftag = 0;
               io.apptag = 0;
               io.appmask = 0;
               
               err = ioctl(fd, NVME_IOCTL_SUBMIT_IO, &io);

               if (err < 0) {
                              goto perror;
               }
               if (err){
                              fprintf(stderr, "nvme write status:%x\n", err);
               }
               fprintf(stderr,"status : %x\n",err);

               close(fd);

               return 0;

perror:
               perror(perrstr);
               return 1;

For the first time I had  " device busy error ",

Then when I ran for second time the nvme0 and namespaces has disappeared from /dev/ directory

Any idea of what happens