1*9bad2a6bSPaolo Bonzini /* 2*9bad2a6bSPaolo Bonzini * Persistent reservation manager that talks to qemu-pr-helper 3*9bad2a6bSPaolo Bonzini * 4*9bad2a6bSPaolo Bonzini * Copyright (c) 2017 Red Hat, Inc. 5*9bad2a6bSPaolo Bonzini * 6*9bad2a6bSPaolo Bonzini * Author: Paolo Bonzini <pbonzini@redhat.com> 7*9bad2a6bSPaolo Bonzini * 8*9bad2a6bSPaolo Bonzini * This code is licensed under the LGPL v2.1 or later. 9*9bad2a6bSPaolo Bonzini * 10*9bad2a6bSPaolo Bonzini */ 11*9bad2a6bSPaolo Bonzini 12*9bad2a6bSPaolo Bonzini #include "qemu/osdep.h" 13*9bad2a6bSPaolo Bonzini #include "qapi/error.h" 14*9bad2a6bSPaolo Bonzini #include "scsi/constants.h" 15*9bad2a6bSPaolo Bonzini #include "scsi/pr-manager.h" 16*9bad2a6bSPaolo Bonzini #include "scsi/utils.h" 17*9bad2a6bSPaolo Bonzini #include "io/channel.h" 18*9bad2a6bSPaolo Bonzini #include "io/channel-socket.h" 19*9bad2a6bSPaolo Bonzini #include "pr-helper.h" 20*9bad2a6bSPaolo Bonzini 21*9bad2a6bSPaolo Bonzini #include <scsi/sg.h> 22*9bad2a6bSPaolo Bonzini 23*9bad2a6bSPaolo Bonzini #define PR_MAX_RECONNECT_ATTEMPTS 5 24*9bad2a6bSPaolo Bonzini 25*9bad2a6bSPaolo Bonzini #define TYPE_PR_MANAGER_HELPER "pr-manager-helper" 26*9bad2a6bSPaolo Bonzini 27*9bad2a6bSPaolo Bonzini #define PR_MANAGER_HELPER(obj) \ 28*9bad2a6bSPaolo Bonzini OBJECT_CHECK(PRManagerHelper, (obj), \ 29*9bad2a6bSPaolo Bonzini TYPE_PR_MANAGER_HELPER) 30*9bad2a6bSPaolo Bonzini 31*9bad2a6bSPaolo Bonzini typedef struct PRManagerHelper { 32*9bad2a6bSPaolo Bonzini /* <private> */ 33*9bad2a6bSPaolo Bonzini PRManager parent; 34*9bad2a6bSPaolo Bonzini 35*9bad2a6bSPaolo Bonzini char *path; 36*9bad2a6bSPaolo Bonzini 37*9bad2a6bSPaolo Bonzini QemuMutex lock; 38*9bad2a6bSPaolo Bonzini QIOChannel *ioc; 39*9bad2a6bSPaolo Bonzini } PRManagerHelper; 40*9bad2a6bSPaolo Bonzini 41*9bad2a6bSPaolo Bonzini /* Called with lock held. */ 42*9bad2a6bSPaolo Bonzini static int pr_manager_helper_read(PRManagerHelper *pr_mgr, 43*9bad2a6bSPaolo Bonzini void *buf, int sz, Error **errp) 44*9bad2a6bSPaolo Bonzini { 45*9bad2a6bSPaolo Bonzini ssize_t r = qio_channel_read_all(pr_mgr->ioc, buf, sz, errp); 46*9bad2a6bSPaolo Bonzini 47*9bad2a6bSPaolo Bonzini if (r < 0) { 48*9bad2a6bSPaolo Bonzini object_unref(OBJECT(pr_mgr->ioc)); 49*9bad2a6bSPaolo Bonzini pr_mgr->ioc = NULL; 50*9bad2a6bSPaolo Bonzini return -EINVAL; 51*9bad2a6bSPaolo Bonzini } 52*9bad2a6bSPaolo Bonzini 53*9bad2a6bSPaolo Bonzini return 0; 54*9bad2a6bSPaolo Bonzini } 55*9bad2a6bSPaolo Bonzini 56*9bad2a6bSPaolo Bonzini /* Called with lock held. */ 57*9bad2a6bSPaolo Bonzini static int pr_manager_helper_write(PRManagerHelper *pr_mgr, 58*9bad2a6bSPaolo Bonzini int fd, 59*9bad2a6bSPaolo Bonzini const void *buf, int sz, Error **errp) 60*9bad2a6bSPaolo Bonzini { 61*9bad2a6bSPaolo Bonzini size_t nfds = (fd != -1); 62*9bad2a6bSPaolo Bonzini while (sz > 0) { 63*9bad2a6bSPaolo Bonzini struct iovec iov; 64*9bad2a6bSPaolo Bonzini ssize_t n_written; 65*9bad2a6bSPaolo Bonzini 66*9bad2a6bSPaolo Bonzini iov.iov_base = (void *)buf; 67*9bad2a6bSPaolo Bonzini iov.iov_len = sz; 68*9bad2a6bSPaolo Bonzini n_written = qio_channel_writev_full(QIO_CHANNEL(pr_mgr->ioc), &iov, 1, 69*9bad2a6bSPaolo Bonzini nfds ? &fd : NULL, nfds, errp); 70*9bad2a6bSPaolo Bonzini 71*9bad2a6bSPaolo Bonzini if (n_written <= 0) { 72*9bad2a6bSPaolo Bonzini assert(n_written != QIO_CHANNEL_ERR_BLOCK); 73*9bad2a6bSPaolo Bonzini object_unref(OBJECT(pr_mgr->ioc)); 74*9bad2a6bSPaolo Bonzini return n_written < 0 ? -EINVAL : 0; 75*9bad2a6bSPaolo Bonzini } 76*9bad2a6bSPaolo Bonzini 77*9bad2a6bSPaolo Bonzini nfds = 0; 78*9bad2a6bSPaolo Bonzini buf += n_written; 79*9bad2a6bSPaolo Bonzini sz -= n_written; 80*9bad2a6bSPaolo Bonzini } 81*9bad2a6bSPaolo Bonzini 82*9bad2a6bSPaolo Bonzini return 0; 83*9bad2a6bSPaolo Bonzini } 84*9bad2a6bSPaolo Bonzini 85*9bad2a6bSPaolo Bonzini /* Called with lock held. */ 86*9bad2a6bSPaolo Bonzini static int pr_manager_helper_initialize(PRManagerHelper *pr_mgr, 87*9bad2a6bSPaolo Bonzini Error **errp) 88*9bad2a6bSPaolo Bonzini { 89*9bad2a6bSPaolo Bonzini char *path = g_strdup(pr_mgr->path); 90*9bad2a6bSPaolo Bonzini SocketAddress saddr = { 91*9bad2a6bSPaolo Bonzini .type = SOCKET_ADDRESS_TYPE_UNIX, 92*9bad2a6bSPaolo Bonzini .u.q_unix.path = path 93*9bad2a6bSPaolo Bonzini }; 94*9bad2a6bSPaolo Bonzini QIOChannelSocket *sioc = qio_channel_socket_new(); 95*9bad2a6bSPaolo Bonzini Error *local_err = NULL; 96*9bad2a6bSPaolo Bonzini 97*9bad2a6bSPaolo Bonzini uint32_t flags; 98*9bad2a6bSPaolo Bonzini int r; 99*9bad2a6bSPaolo Bonzini 100*9bad2a6bSPaolo Bonzini assert(!pr_mgr->ioc); 101*9bad2a6bSPaolo Bonzini qio_channel_set_name(QIO_CHANNEL(sioc), "pr-manager-helper"); 102*9bad2a6bSPaolo Bonzini qio_channel_socket_connect_sync(sioc, 103*9bad2a6bSPaolo Bonzini &saddr, 104*9bad2a6bSPaolo Bonzini &local_err); 105*9bad2a6bSPaolo Bonzini g_free(path); 106*9bad2a6bSPaolo Bonzini if (local_err) { 107*9bad2a6bSPaolo Bonzini object_unref(OBJECT(sioc)); 108*9bad2a6bSPaolo Bonzini error_propagate(errp, local_err); 109*9bad2a6bSPaolo Bonzini return -ENOTCONN; 110*9bad2a6bSPaolo Bonzini } 111*9bad2a6bSPaolo Bonzini 112*9bad2a6bSPaolo Bonzini qio_channel_set_delay(QIO_CHANNEL(sioc), false); 113*9bad2a6bSPaolo Bonzini pr_mgr->ioc = QIO_CHANNEL(sioc); 114*9bad2a6bSPaolo Bonzini 115*9bad2a6bSPaolo Bonzini /* A simple feature negotation protocol, even though there is 116*9bad2a6bSPaolo Bonzini * no optional feature right now. 117*9bad2a6bSPaolo Bonzini */ 118*9bad2a6bSPaolo Bonzini r = pr_manager_helper_read(pr_mgr, &flags, sizeof(flags), errp); 119*9bad2a6bSPaolo Bonzini if (r < 0) { 120*9bad2a6bSPaolo Bonzini goto out_close; 121*9bad2a6bSPaolo Bonzini } 122*9bad2a6bSPaolo Bonzini 123*9bad2a6bSPaolo Bonzini flags = 0; 124*9bad2a6bSPaolo Bonzini r = pr_manager_helper_write(pr_mgr, -1, &flags, sizeof(flags), errp); 125*9bad2a6bSPaolo Bonzini if (r < 0) { 126*9bad2a6bSPaolo Bonzini goto out_close; 127*9bad2a6bSPaolo Bonzini } 128*9bad2a6bSPaolo Bonzini 129*9bad2a6bSPaolo Bonzini return 0; 130*9bad2a6bSPaolo Bonzini 131*9bad2a6bSPaolo Bonzini out_close: 132*9bad2a6bSPaolo Bonzini object_unref(OBJECT(pr_mgr->ioc)); 133*9bad2a6bSPaolo Bonzini pr_mgr->ioc = NULL; 134*9bad2a6bSPaolo Bonzini return r; 135*9bad2a6bSPaolo Bonzini } 136*9bad2a6bSPaolo Bonzini 137*9bad2a6bSPaolo Bonzini static int pr_manager_helper_run(PRManager *p, 138*9bad2a6bSPaolo Bonzini int fd, struct sg_io_hdr *io_hdr) 139*9bad2a6bSPaolo Bonzini { 140*9bad2a6bSPaolo Bonzini PRManagerHelper *pr_mgr = PR_MANAGER_HELPER(p); 141*9bad2a6bSPaolo Bonzini 142*9bad2a6bSPaolo Bonzini uint32_t len; 143*9bad2a6bSPaolo Bonzini PRHelperResponse resp; 144*9bad2a6bSPaolo Bonzini int ret; 145*9bad2a6bSPaolo Bonzini int expected_dir; 146*9bad2a6bSPaolo Bonzini int attempts; 147*9bad2a6bSPaolo Bonzini uint8_t cdb[PR_HELPER_CDB_SIZE] = { 0 }; 148*9bad2a6bSPaolo Bonzini 149*9bad2a6bSPaolo Bonzini if (!io_hdr->cmd_len || io_hdr->cmd_len > PR_HELPER_CDB_SIZE) { 150*9bad2a6bSPaolo Bonzini return -EINVAL; 151*9bad2a6bSPaolo Bonzini } 152*9bad2a6bSPaolo Bonzini 153*9bad2a6bSPaolo Bonzini memcpy(cdb, io_hdr->cmdp, io_hdr->cmd_len); 154*9bad2a6bSPaolo Bonzini assert(cdb[0] == PERSISTENT_RESERVE_OUT || cdb[0] == PERSISTENT_RESERVE_IN); 155*9bad2a6bSPaolo Bonzini expected_dir = 156*9bad2a6bSPaolo Bonzini (cdb[0] == PERSISTENT_RESERVE_OUT ? SG_DXFER_TO_DEV : SG_DXFER_FROM_DEV); 157*9bad2a6bSPaolo Bonzini if (io_hdr->dxfer_direction != expected_dir) { 158*9bad2a6bSPaolo Bonzini return -EINVAL; 159*9bad2a6bSPaolo Bonzini } 160*9bad2a6bSPaolo Bonzini 161*9bad2a6bSPaolo Bonzini len = scsi_cdb_xfer(cdb); 162*9bad2a6bSPaolo Bonzini if (io_hdr->dxfer_len < len || len > PR_HELPER_DATA_SIZE) { 163*9bad2a6bSPaolo Bonzini return -EINVAL; 164*9bad2a6bSPaolo Bonzini } 165*9bad2a6bSPaolo Bonzini 166*9bad2a6bSPaolo Bonzini qemu_mutex_lock(&pr_mgr->lock); 167*9bad2a6bSPaolo Bonzini 168*9bad2a6bSPaolo Bonzini /* Try to reconnect while sending the CDB. */ 169*9bad2a6bSPaolo Bonzini for (attempts = 0; attempts < PR_MAX_RECONNECT_ATTEMPTS; attempts++) { 170*9bad2a6bSPaolo Bonzini if (!pr_mgr->ioc) { 171*9bad2a6bSPaolo Bonzini ret = pr_manager_helper_initialize(pr_mgr, NULL); 172*9bad2a6bSPaolo Bonzini if (ret < 0) { 173*9bad2a6bSPaolo Bonzini qemu_mutex_unlock(&pr_mgr->lock); 174*9bad2a6bSPaolo Bonzini g_usleep(G_USEC_PER_SEC); 175*9bad2a6bSPaolo Bonzini qemu_mutex_lock(&pr_mgr->lock); 176*9bad2a6bSPaolo Bonzini continue; 177*9bad2a6bSPaolo Bonzini } 178*9bad2a6bSPaolo Bonzini } 179*9bad2a6bSPaolo Bonzini 180*9bad2a6bSPaolo Bonzini ret = pr_manager_helper_write(pr_mgr, fd, cdb, ARRAY_SIZE(cdb), NULL); 181*9bad2a6bSPaolo Bonzini if (ret >= 0) { 182*9bad2a6bSPaolo Bonzini break; 183*9bad2a6bSPaolo Bonzini } 184*9bad2a6bSPaolo Bonzini } 185*9bad2a6bSPaolo Bonzini if (ret < 0) { 186*9bad2a6bSPaolo Bonzini goto out; 187*9bad2a6bSPaolo Bonzini } 188*9bad2a6bSPaolo Bonzini 189*9bad2a6bSPaolo Bonzini /* After sending the CDB, any communications failure causes the 190*9bad2a6bSPaolo Bonzini * command to fail. The failure is transient, retrying the command 191*9bad2a6bSPaolo Bonzini * will invoke pr_manager_helper_initialize again. 192*9bad2a6bSPaolo Bonzini */ 193*9bad2a6bSPaolo Bonzini if (expected_dir == SG_DXFER_TO_DEV) { 194*9bad2a6bSPaolo Bonzini io_hdr->resid = io_hdr->dxfer_len - len; 195*9bad2a6bSPaolo Bonzini ret = pr_manager_helper_write(pr_mgr, -1, io_hdr->dxferp, len, NULL); 196*9bad2a6bSPaolo Bonzini if (ret < 0) { 197*9bad2a6bSPaolo Bonzini goto out; 198*9bad2a6bSPaolo Bonzini } 199*9bad2a6bSPaolo Bonzini } 200*9bad2a6bSPaolo Bonzini ret = pr_manager_helper_read(pr_mgr, &resp, sizeof(resp), NULL); 201*9bad2a6bSPaolo Bonzini if (ret < 0) { 202*9bad2a6bSPaolo Bonzini goto out; 203*9bad2a6bSPaolo Bonzini } 204*9bad2a6bSPaolo Bonzini 205*9bad2a6bSPaolo Bonzini resp.result = be32_to_cpu(resp.result); 206*9bad2a6bSPaolo Bonzini resp.sz = be32_to_cpu(resp.sz); 207*9bad2a6bSPaolo Bonzini if (io_hdr->dxfer_direction == SG_DXFER_FROM_DEV) { 208*9bad2a6bSPaolo Bonzini assert(resp.sz <= io_hdr->dxfer_len); 209*9bad2a6bSPaolo Bonzini ret = pr_manager_helper_read(pr_mgr, io_hdr->dxferp, resp.sz, NULL); 210*9bad2a6bSPaolo Bonzini if (ret < 0) { 211*9bad2a6bSPaolo Bonzini goto out; 212*9bad2a6bSPaolo Bonzini } 213*9bad2a6bSPaolo Bonzini io_hdr->resid = io_hdr->dxfer_len - resp.sz; 214*9bad2a6bSPaolo Bonzini } else { 215*9bad2a6bSPaolo Bonzini assert(resp.sz == 0); 216*9bad2a6bSPaolo Bonzini } 217*9bad2a6bSPaolo Bonzini 218*9bad2a6bSPaolo Bonzini io_hdr->status = resp.result; 219*9bad2a6bSPaolo Bonzini if (resp.result == CHECK_CONDITION) { 220*9bad2a6bSPaolo Bonzini io_hdr->driver_status = SG_ERR_DRIVER_SENSE; 221*9bad2a6bSPaolo Bonzini io_hdr->sb_len_wr = MIN(io_hdr->mx_sb_len, PR_HELPER_SENSE_SIZE); 222*9bad2a6bSPaolo Bonzini memcpy(io_hdr->sbp, resp.sense, io_hdr->sb_len_wr); 223*9bad2a6bSPaolo Bonzini } 224*9bad2a6bSPaolo Bonzini 225*9bad2a6bSPaolo Bonzini out: 226*9bad2a6bSPaolo Bonzini if (ret < 0) { 227*9bad2a6bSPaolo Bonzini int sense_len = scsi_build_sense(io_hdr->sbp, 228*9bad2a6bSPaolo Bonzini SENSE_CODE(LUN_COMM_FAILURE)); 229*9bad2a6bSPaolo Bonzini io_hdr->driver_status = SG_ERR_DRIVER_SENSE; 230*9bad2a6bSPaolo Bonzini io_hdr->sb_len_wr = MIN(io_hdr->mx_sb_len, sense_len); 231*9bad2a6bSPaolo Bonzini io_hdr->status = CHECK_CONDITION; 232*9bad2a6bSPaolo Bonzini } 233*9bad2a6bSPaolo Bonzini qemu_mutex_unlock(&pr_mgr->lock); 234*9bad2a6bSPaolo Bonzini return ret; 235*9bad2a6bSPaolo Bonzini } 236*9bad2a6bSPaolo Bonzini 237*9bad2a6bSPaolo Bonzini static void pr_manager_helper_complete(UserCreatable *uc, Error **errp) 238*9bad2a6bSPaolo Bonzini { 239*9bad2a6bSPaolo Bonzini PRManagerHelper *pr_mgr = PR_MANAGER_HELPER(uc); 240*9bad2a6bSPaolo Bonzini 241*9bad2a6bSPaolo Bonzini qemu_mutex_lock(&pr_mgr->lock); 242*9bad2a6bSPaolo Bonzini pr_manager_helper_initialize(pr_mgr, errp); 243*9bad2a6bSPaolo Bonzini qemu_mutex_unlock(&pr_mgr->lock); 244*9bad2a6bSPaolo Bonzini } 245*9bad2a6bSPaolo Bonzini 246*9bad2a6bSPaolo Bonzini static char *get_path(Object *obj, Error **errp) 247*9bad2a6bSPaolo Bonzini { 248*9bad2a6bSPaolo Bonzini PRManagerHelper *pr_mgr = PR_MANAGER_HELPER(obj); 249*9bad2a6bSPaolo Bonzini 250*9bad2a6bSPaolo Bonzini return g_strdup(pr_mgr->path); 251*9bad2a6bSPaolo Bonzini } 252*9bad2a6bSPaolo Bonzini 253*9bad2a6bSPaolo Bonzini static void set_path(Object *obj, const char *str, Error **errp) 254*9bad2a6bSPaolo Bonzini { 255*9bad2a6bSPaolo Bonzini PRManagerHelper *pr_mgr = PR_MANAGER_HELPER(obj); 256*9bad2a6bSPaolo Bonzini 257*9bad2a6bSPaolo Bonzini g_free(pr_mgr->path); 258*9bad2a6bSPaolo Bonzini pr_mgr->path = g_strdup(str); 259*9bad2a6bSPaolo Bonzini } 260*9bad2a6bSPaolo Bonzini 261*9bad2a6bSPaolo Bonzini static void pr_manager_helper_instance_finalize(Object *obj) 262*9bad2a6bSPaolo Bonzini { 263*9bad2a6bSPaolo Bonzini PRManagerHelper *pr_mgr = PR_MANAGER_HELPER(obj); 264*9bad2a6bSPaolo Bonzini 265*9bad2a6bSPaolo Bonzini object_unref(OBJECT(pr_mgr->ioc)); 266*9bad2a6bSPaolo Bonzini qemu_mutex_destroy(&pr_mgr->lock); 267*9bad2a6bSPaolo Bonzini } 268*9bad2a6bSPaolo Bonzini 269*9bad2a6bSPaolo Bonzini static void pr_manager_helper_instance_init(Object *obj) 270*9bad2a6bSPaolo Bonzini { 271*9bad2a6bSPaolo Bonzini PRManagerHelper *pr_mgr = PR_MANAGER_HELPER(obj); 272*9bad2a6bSPaolo Bonzini 273*9bad2a6bSPaolo Bonzini qemu_mutex_init(&pr_mgr->lock); 274*9bad2a6bSPaolo Bonzini } 275*9bad2a6bSPaolo Bonzini 276*9bad2a6bSPaolo Bonzini static void pr_manager_helper_class_init(ObjectClass *klass, 277*9bad2a6bSPaolo Bonzini void *class_data G_GNUC_UNUSED) 278*9bad2a6bSPaolo Bonzini { 279*9bad2a6bSPaolo Bonzini PRManagerClass *prmgr_klass = PR_MANAGER_CLASS(klass); 280*9bad2a6bSPaolo Bonzini UserCreatableClass *uc_klass = USER_CREATABLE_CLASS(klass); 281*9bad2a6bSPaolo Bonzini 282*9bad2a6bSPaolo Bonzini object_class_property_add_str(klass, "path", get_path, set_path, 283*9bad2a6bSPaolo Bonzini &error_abort); 284*9bad2a6bSPaolo Bonzini uc_klass->complete = pr_manager_helper_complete; 285*9bad2a6bSPaolo Bonzini prmgr_klass->run = pr_manager_helper_run; 286*9bad2a6bSPaolo Bonzini } 287*9bad2a6bSPaolo Bonzini 288*9bad2a6bSPaolo Bonzini static const TypeInfo pr_manager_helper_info = { 289*9bad2a6bSPaolo Bonzini .parent = TYPE_PR_MANAGER, 290*9bad2a6bSPaolo Bonzini .name = TYPE_PR_MANAGER_HELPER, 291*9bad2a6bSPaolo Bonzini .instance_size = sizeof(PRManagerHelper), 292*9bad2a6bSPaolo Bonzini .instance_init = pr_manager_helper_instance_init, 293*9bad2a6bSPaolo Bonzini .instance_finalize = pr_manager_helper_instance_finalize, 294*9bad2a6bSPaolo Bonzini .class_init = pr_manager_helper_class_init, 295*9bad2a6bSPaolo Bonzini }; 296*9bad2a6bSPaolo Bonzini 297*9bad2a6bSPaolo Bonzini static void pr_manager_helper_register_types(void) 298*9bad2a6bSPaolo Bonzini { 299*9bad2a6bSPaolo Bonzini type_register_static(&pr_manager_helper_info); 300*9bad2a6bSPaolo Bonzini } 301*9bad2a6bSPaolo Bonzini 302*9bad2a6bSPaolo Bonzini type_init(pr_manager_helper_register_types); 303