1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2013 Shaohua Li <shli@kernel.org> 4 * Copyright (C) 2014 Red Hat, Inc. 5 * Copyright (C) 2015 Arrikto, Inc. 6 * Copyright (C) 2017 Chinamobile, Inc. 7 */ 8 9 #include <linux/spinlock.h> 10 #include <linux/module.h> 11 #include <linux/kernel.h> 12 #include <linux/timer.h> 13 #include <linux/parser.h> 14 #include <linux/vmalloc.h> 15 #include <linux/uio_driver.h> 16 #include <linux/xarray.h> 17 #include <linux/stringify.h> 18 #include <linux/bitops.h> 19 #include <linux/highmem.h> 20 #include <linux/configfs.h> 21 #include <linux/mutex.h> 22 #include <linux/workqueue.h> 23 #include <linux/pagemap.h> 24 #include <net/genetlink.h> 25 #include <scsi/scsi_common.h> 26 #include <scsi/scsi_proto.h> 27 #include <target/target_core_base.h> 28 #include <target/target_core_fabric.h> 29 #include <target/target_core_backend.h> 30 31 #include <linux/target_core_user.h> 32 33 /** 34 * DOC: Userspace I/O 35 * Userspace I/O 36 * ------------- 37 * 38 * Define a shared-memory interface for LIO to pass SCSI commands and 39 * data to userspace for processing. This is to allow backends that 40 * are too complex for in-kernel support to be possible. 41 * 42 * It uses the UIO framework to do a lot of the device-creation and 43 * introspection work for us. 44 * 45 * See the .h file for how the ring is laid out. Note that while the 46 * command ring is defined, the particulars of the data area are 47 * not. Offset values in the command entry point to other locations 48 * internal to the mmap-ed area. There is separate space outside the 49 * command ring for data buffers. This leaves maximum flexibility for 50 * moving buffer allocations, or even page flipping or other 51 * allocation techniques, without altering the command ring layout. 52 * 53 * SECURITY: 54 * The user process must be assumed to be malicious. There's no way to 55 * prevent it breaking the command ring protocol if it wants, but in 56 * order to prevent other issues we must only ever read *data* from 57 * the shared memory area, not offsets or sizes. This applies to 58 * command ring entries as well as the mailbox. Extra code needed for 59 * this may have a 'UAM' comment. 60 */ 61 62 #define TCMU_TIME_OUT (30 * MSEC_PER_SEC) 63 64 /* For mailbox plus cmd ring, the size is fixed 8MB */ 65 #define MB_CMDR_SIZE (8 * 1024 * 1024) 66 /* Offset of cmd ring is size of mailbox */ 67 #define CMDR_OFF sizeof(struct tcmu_mailbox) 68 #define CMDR_SIZE (MB_CMDR_SIZE - CMDR_OFF) 69 70 /* 71 * For data area, the default block size is PAGE_SIZE and 72 * the default total size is 256K * PAGE_SIZE. 73 */ 74 #define DATA_PAGES_PER_BLK_DEF 1 75 #define DATA_AREA_PAGES_DEF (256 * 1024) 76 77 #define TCMU_MBS_TO_PAGES(_mbs) ((size_t)_mbs << (20 - PAGE_SHIFT)) 78 #define TCMU_PAGES_TO_MBS(_pages) (_pages >> (20 - PAGE_SHIFT)) 79 80 /* 81 * Default number of global data blocks(512K * PAGE_SIZE) 82 * when the unmap thread will be started. 83 */ 84 #define TCMU_GLOBAL_MAX_PAGES_DEF (512 * 1024) 85 86 static u8 tcmu_kern_cmd_reply_supported; 87 static u8 tcmu_netlink_blocked; 88 89 static struct device *tcmu_root_device; 90 91 struct tcmu_hba { 92 u32 host_id; 93 }; 94 95 #define TCMU_CONFIG_LEN 256 96 97 static DEFINE_MUTEX(tcmu_nl_cmd_mutex); 98 static LIST_HEAD(tcmu_nl_cmd_list); 99 100 struct tcmu_dev; 101 102 struct tcmu_nl_cmd { 103 /* wake up thread waiting for reply */ 104 struct completion complete; 105 struct list_head nl_list; 106 struct tcmu_dev *udev; 107 int cmd; 108 int status; 109 }; 110 111 struct tcmu_dev { 112 struct list_head node; 113 struct kref kref; 114 115 struct se_device se_dev; 116 struct se_dev_plug se_plug; 117 118 char *name; 119 struct se_hba *hba; 120 121 #define TCMU_DEV_BIT_OPEN 0 122 #define TCMU_DEV_BIT_BROKEN 1 123 #define TCMU_DEV_BIT_BLOCKED 2 124 #define TCMU_DEV_BIT_TMR_NOTIFY 3 125 #define TCMU_DEV_BIT_PLUGGED 4 126 unsigned long flags; 127 128 struct uio_info uio_info; 129 130 struct inode *inode; 131 132 uint64_t dev_size; 133 134 struct tcmu_mailbox *mb_addr; 135 void *cmdr; 136 u32 cmdr_size; 137 u32 cmdr_last_cleaned; 138 /* Offset of data area from start of mb */ 139 /* Must add data_off and mb_addr to get the address */ 140 size_t data_off; 141 int data_area_mb; 142 uint32_t max_blocks; 143 size_t mmap_pages; 144 145 struct mutex cmdr_lock; 146 struct list_head qfull_queue; 147 struct list_head tmr_queue; 148 149 uint32_t dbi_max; 150 uint32_t dbi_thresh; 151 unsigned long *data_bitmap; 152 struct xarray data_pages; 153 uint32_t data_pages_per_blk; 154 uint32_t data_blk_size; 155 156 struct xarray commands; 157 158 struct timer_list cmd_timer; 159 unsigned int cmd_time_out; 160 struct list_head inflight_queue; 161 162 struct timer_list qfull_timer; 163 int qfull_time_out; 164 165 struct list_head timedout_entry; 166 167 struct tcmu_nl_cmd curr_nl_cmd; 168 169 char dev_config[TCMU_CONFIG_LEN]; 170 171 int nl_reply_supported; 172 }; 173 174 #define TCMU_DEV(_se_dev) container_of(_se_dev, struct tcmu_dev, se_dev) 175 176 struct tcmu_cmd { 177 struct se_cmd *se_cmd; 178 struct tcmu_dev *tcmu_dev; 179 struct list_head queue_entry; 180 181 uint16_t cmd_id; 182 183 /* Can't use se_cmd when cleaning up expired cmds, because if 184 cmd has been completed then accessing se_cmd is off limits */ 185 uint32_t dbi_cnt; 186 uint32_t dbi_bidi_cnt; 187 uint32_t dbi_cur; 188 uint32_t *dbi; 189 190 uint32_t data_len_bidi; 191 192 unsigned long deadline; 193 194 #define TCMU_CMD_BIT_EXPIRED 0 195 #define TCMU_CMD_BIT_KEEP_BUF 1 196 unsigned long flags; 197 }; 198 199 struct tcmu_tmr { 200 struct list_head queue_entry; 201 202 uint8_t tmr_type; 203 uint32_t tmr_cmd_cnt; 204 int16_t tmr_cmd_ids[]; 205 }; 206 207 /* 208 * To avoid dead lock the mutex lock order should always be: 209 * 210 * mutex_lock(&root_udev_mutex); 211 * ... 212 * mutex_lock(&tcmu_dev->cmdr_lock); 213 * mutex_unlock(&tcmu_dev->cmdr_lock); 214 * ... 215 * mutex_unlock(&root_udev_mutex); 216 */ 217 static DEFINE_MUTEX(root_udev_mutex); 218 static LIST_HEAD(root_udev); 219 220 static DEFINE_SPINLOCK(timed_out_udevs_lock); 221 static LIST_HEAD(timed_out_udevs); 222 223 static struct kmem_cache *tcmu_cmd_cache; 224 225 static atomic_t global_page_count = ATOMIC_INIT(0); 226 static struct delayed_work tcmu_unmap_work; 227 static int tcmu_global_max_pages = TCMU_GLOBAL_MAX_PAGES_DEF; 228 229 static int tcmu_set_global_max_data_area(const char *str, 230 const struct kernel_param *kp) 231 { 232 int ret, max_area_mb; 233 234 ret = kstrtoint(str, 10, &max_area_mb); 235 if (ret) 236 return -EINVAL; 237 238 if (max_area_mb <= 0) { 239 pr_err("global_max_data_area must be larger than 0.\n"); 240 return -EINVAL; 241 } 242 243 tcmu_global_max_pages = TCMU_MBS_TO_PAGES(max_area_mb); 244 if (atomic_read(&global_page_count) > tcmu_global_max_pages) 245 schedule_delayed_work(&tcmu_unmap_work, 0); 246 else 247 cancel_delayed_work_sync(&tcmu_unmap_work); 248 249 return 0; 250 } 251 252 static int tcmu_get_global_max_data_area(char *buffer, 253 const struct kernel_param *kp) 254 { 255 return sprintf(buffer, "%d\n", TCMU_PAGES_TO_MBS(tcmu_global_max_pages)); 256 } 257 258 static const struct kernel_param_ops tcmu_global_max_data_area_op = { 259 .set = tcmu_set_global_max_data_area, 260 .get = tcmu_get_global_max_data_area, 261 }; 262 263 module_param_cb(global_max_data_area_mb, &tcmu_global_max_data_area_op, NULL, 264 S_IWUSR | S_IRUGO); 265 MODULE_PARM_DESC(global_max_data_area_mb, 266 "Max MBs allowed to be allocated to all the tcmu device's " 267 "data areas."); 268 269 static int tcmu_get_block_netlink(char *buffer, 270 const struct kernel_param *kp) 271 { 272 return sprintf(buffer, "%s\n", tcmu_netlink_blocked ? 273 "blocked" : "unblocked"); 274 } 275 276 static int tcmu_set_block_netlink(const char *str, 277 const struct kernel_param *kp) 278 { 279 int ret; 280 u8 val; 281 282 ret = kstrtou8(str, 0, &val); 283 if (ret < 0) 284 return ret; 285 286 if (val > 1) { 287 pr_err("Invalid block netlink value %u\n", val); 288 return -EINVAL; 289 } 290 291 tcmu_netlink_blocked = val; 292 return 0; 293 } 294 295 static const struct kernel_param_ops tcmu_block_netlink_op = { 296 .set = tcmu_set_block_netlink, 297 .get = tcmu_get_block_netlink, 298 }; 299 300 module_param_cb(block_netlink, &tcmu_block_netlink_op, NULL, S_IWUSR | S_IRUGO); 301 MODULE_PARM_DESC(block_netlink, "Block new netlink commands."); 302 303 static int tcmu_fail_netlink_cmd(struct tcmu_nl_cmd *nl_cmd) 304 { 305 struct tcmu_dev *udev = nl_cmd->udev; 306 307 if (!tcmu_netlink_blocked) { 308 pr_err("Could not reset device's netlink interface. Netlink is not blocked.\n"); 309 return -EBUSY; 310 } 311 312 if (nl_cmd->cmd != TCMU_CMD_UNSPEC) { 313 pr_debug("Aborting nl cmd %d on %s\n", nl_cmd->cmd, udev->name); 314 nl_cmd->status = -EINTR; 315 list_del(&nl_cmd->nl_list); 316 complete(&nl_cmd->complete); 317 } 318 return 0; 319 } 320 321 static int tcmu_set_reset_netlink(const char *str, 322 const struct kernel_param *kp) 323 { 324 struct tcmu_nl_cmd *nl_cmd, *tmp_cmd; 325 int ret; 326 u8 val; 327 328 ret = kstrtou8(str, 0, &val); 329 if (ret < 0) 330 return ret; 331 332 if (val != 1) { 333 pr_err("Invalid reset netlink value %u\n", val); 334 return -EINVAL; 335 } 336 337 mutex_lock(&tcmu_nl_cmd_mutex); 338 list_for_each_entry_safe(nl_cmd, tmp_cmd, &tcmu_nl_cmd_list, nl_list) { 339 ret = tcmu_fail_netlink_cmd(nl_cmd); 340 if (ret) 341 break; 342 } 343 mutex_unlock(&tcmu_nl_cmd_mutex); 344 345 return ret; 346 } 347 348 static const struct kernel_param_ops tcmu_reset_netlink_op = { 349 .set = tcmu_set_reset_netlink, 350 }; 351 352 module_param_cb(reset_netlink, &tcmu_reset_netlink_op, NULL, S_IWUSR); 353 MODULE_PARM_DESC(reset_netlink, "Reset netlink commands."); 354 355 /* multicast group */ 356 enum tcmu_multicast_groups { 357 TCMU_MCGRP_CONFIG, 358 }; 359 360 static const struct genl_multicast_group tcmu_mcgrps[] = { 361 [TCMU_MCGRP_CONFIG] = { .name = "config", }, 362 }; 363 364 static struct nla_policy tcmu_attr_policy[TCMU_ATTR_MAX+1] = { 365 [TCMU_ATTR_DEVICE] = { .type = NLA_STRING }, 366 [TCMU_ATTR_MINOR] = { .type = NLA_U32 }, 367 [TCMU_ATTR_CMD_STATUS] = { .type = NLA_S32 }, 368 [TCMU_ATTR_DEVICE_ID] = { .type = NLA_U32 }, 369 [TCMU_ATTR_SUPP_KERN_CMD_REPLY] = { .type = NLA_U8 }, 370 }; 371 372 static int tcmu_genl_cmd_done(struct genl_info *info, int completed_cmd) 373 { 374 struct tcmu_dev *udev = NULL; 375 struct tcmu_nl_cmd *nl_cmd; 376 int dev_id, rc, ret = 0; 377 378 if (!info->attrs[TCMU_ATTR_CMD_STATUS] || 379 !info->attrs[TCMU_ATTR_DEVICE_ID]) { 380 printk(KERN_ERR "TCMU_ATTR_CMD_STATUS or TCMU_ATTR_DEVICE_ID not set, doing nothing\n"); 381 return -EINVAL; 382 } 383 384 dev_id = nla_get_u32(info->attrs[TCMU_ATTR_DEVICE_ID]); 385 rc = nla_get_s32(info->attrs[TCMU_ATTR_CMD_STATUS]); 386 387 mutex_lock(&tcmu_nl_cmd_mutex); 388 list_for_each_entry(nl_cmd, &tcmu_nl_cmd_list, nl_list) { 389 if (nl_cmd->udev->se_dev.dev_index == dev_id) { 390 udev = nl_cmd->udev; 391 break; 392 } 393 } 394 395 if (!udev) { 396 pr_err("tcmu nl cmd %u/%d completion could not find device with dev id %u.\n", 397 completed_cmd, rc, dev_id); 398 ret = -ENODEV; 399 goto unlock; 400 } 401 list_del(&nl_cmd->nl_list); 402 403 pr_debug("%s genl cmd done got id %d curr %d done %d rc %d stat %d\n", 404 udev->name, dev_id, nl_cmd->cmd, completed_cmd, rc, 405 nl_cmd->status); 406 407 if (nl_cmd->cmd != completed_cmd) { 408 pr_err("Mismatched commands on %s (Expecting reply for %d. Current %d).\n", 409 udev->name, completed_cmd, nl_cmd->cmd); 410 ret = -EINVAL; 411 goto unlock; 412 } 413 414 nl_cmd->status = rc; 415 complete(&nl_cmd->complete); 416 unlock: 417 mutex_unlock(&tcmu_nl_cmd_mutex); 418 return ret; 419 } 420 421 static int tcmu_genl_rm_dev_done(struct sk_buff *skb, struct genl_info *info) 422 { 423 return tcmu_genl_cmd_done(info, TCMU_CMD_REMOVED_DEVICE); 424 } 425 426 static int tcmu_genl_add_dev_done(struct sk_buff *skb, struct genl_info *info) 427 { 428 return tcmu_genl_cmd_done(info, TCMU_CMD_ADDED_DEVICE); 429 } 430 431 static int tcmu_genl_reconfig_dev_done(struct sk_buff *skb, 432 struct genl_info *info) 433 { 434 return tcmu_genl_cmd_done(info, TCMU_CMD_RECONFIG_DEVICE); 435 } 436 437 static int tcmu_genl_set_features(struct sk_buff *skb, struct genl_info *info) 438 { 439 if (info->attrs[TCMU_ATTR_SUPP_KERN_CMD_REPLY]) { 440 tcmu_kern_cmd_reply_supported = 441 nla_get_u8(info->attrs[TCMU_ATTR_SUPP_KERN_CMD_REPLY]); 442 printk(KERN_INFO "tcmu daemon: command reply support %u.\n", 443 tcmu_kern_cmd_reply_supported); 444 } 445 446 return 0; 447 } 448 449 static const struct genl_small_ops tcmu_genl_ops[] = { 450 { 451 .cmd = TCMU_CMD_SET_FEATURES, 452 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 453 .flags = GENL_ADMIN_PERM, 454 .doit = tcmu_genl_set_features, 455 }, 456 { 457 .cmd = TCMU_CMD_ADDED_DEVICE_DONE, 458 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 459 .flags = GENL_ADMIN_PERM, 460 .doit = tcmu_genl_add_dev_done, 461 }, 462 { 463 .cmd = TCMU_CMD_REMOVED_DEVICE_DONE, 464 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 465 .flags = GENL_ADMIN_PERM, 466 .doit = tcmu_genl_rm_dev_done, 467 }, 468 { 469 .cmd = TCMU_CMD_RECONFIG_DEVICE_DONE, 470 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 471 .flags = GENL_ADMIN_PERM, 472 .doit = tcmu_genl_reconfig_dev_done, 473 }, 474 }; 475 476 /* Our generic netlink family */ 477 static struct genl_family tcmu_genl_family __ro_after_init = { 478 .module = THIS_MODULE, 479 .hdrsize = 0, 480 .name = "TCM-USER", 481 .version = 2, 482 .maxattr = TCMU_ATTR_MAX, 483 .policy = tcmu_attr_policy, 484 .mcgrps = tcmu_mcgrps, 485 .n_mcgrps = ARRAY_SIZE(tcmu_mcgrps), 486 .netnsok = true, 487 .small_ops = tcmu_genl_ops, 488 .n_small_ops = ARRAY_SIZE(tcmu_genl_ops), 489 }; 490 491 #define tcmu_cmd_set_dbi_cur(cmd, index) ((cmd)->dbi_cur = (index)) 492 #define tcmu_cmd_reset_dbi_cur(cmd) tcmu_cmd_set_dbi_cur(cmd, 0) 493 #define tcmu_cmd_set_dbi(cmd, index) ((cmd)->dbi[(cmd)->dbi_cur++] = (index)) 494 #define tcmu_cmd_get_dbi(cmd) ((cmd)->dbi[(cmd)->dbi_cur++]) 495 496 static void tcmu_cmd_free_data(struct tcmu_cmd *tcmu_cmd, uint32_t len) 497 { 498 struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; 499 uint32_t i; 500 501 for (i = 0; i < len; i++) 502 clear_bit(tcmu_cmd->dbi[i], udev->data_bitmap); 503 } 504 505 static inline int tcmu_get_empty_block(struct tcmu_dev *udev, 506 struct tcmu_cmd *tcmu_cmd, 507 int prev_dbi, int length, int *iov_cnt) 508 { 509 XA_STATE(xas, &udev->data_pages, 0); 510 struct page *page; 511 int i, cnt, dbi, dpi; 512 int page_cnt = DIV_ROUND_UP(length, PAGE_SIZE); 513 514 dbi = find_first_zero_bit(udev->data_bitmap, udev->dbi_thresh); 515 if (dbi == udev->dbi_thresh) 516 return -1; 517 518 dpi = dbi * udev->data_pages_per_blk; 519 /* Count the number of already allocated pages */ 520 xas_set(&xas, dpi); 521 rcu_read_lock(); 522 for (cnt = 0; xas_next(&xas) && cnt < page_cnt;) 523 cnt++; 524 rcu_read_unlock(); 525 526 for (i = cnt; i < page_cnt; i++) { 527 /* try to get new page from the mm */ 528 page = alloc_page(GFP_NOIO); 529 if (!page) 530 break; 531 532 if (xa_store(&udev->data_pages, dpi + i, page, GFP_NOIO)) { 533 __free_page(page); 534 break; 535 } 536 } 537 if (atomic_add_return(i - cnt, &global_page_count) > 538 tcmu_global_max_pages) 539 schedule_delayed_work(&tcmu_unmap_work, 0); 540 541 if (i && dbi > udev->dbi_max) 542 udev->dbi_max = dbi; 543 544 set_bit(dbi, udev->data_bitmap); 545 tcmu_cmd_set_dbi(tcmu_cmd, dbi); 546 547 if (dbi != prev_dbi + 1) 548 *iov_cnt += 1; 549 550 return i == page_cnt ? dbi : -1; 551 } 552 553 static int tcmu_get_empty_blocks(struct tcmu_dev *udev, 554 struct tcmu_cmd *tcmu_cmd, int length) 555 { 556 /* start value of dbi + 1 must not be a valid dbi */ 557 int dbi = -2; 558 int blk_data_len, iov_cnt = 0; 559 uint32_t blk_size = udev->data_blk_size; 560 561 for (; length > 0; length -= blk_size) { 562 blk_data_len = min_t(uint32_t, length, blk_size); 563 dbi = tcmu_get_empty_block(udev, tcmu_cmd, dbi, blk_data_len, 564 &iov_cnt); 565 if (dbi < 0) 566 return -1; 567 } 568 return iov_cnt; 569 } 570 571 static inline void tcmu_free_cmd(struct tcmu_cmd *tcmu_cmd) 572 { 573 kfree(tcmu_cmd->dbi); 574 kmem_cache_free(tcmu_cmd_cache, tcmu_cmd); 575 } 576 577 static inline void tcmu_cmd_set_block_cnts(struct tcmu_cmd *cmd) 578 { 579 int i, len; 580 struct se_cmd *se_cmd = cmd->se_cmd; 581 uint32_t blk_size = cmd->tcmu_dev->data_blk_size; 582 583 cmd->dbi_cnt = DIV_ROUND_UP(se_cmd->data_length, blk_size); 584 585 if (se_cmd->se_cmd_flags & SCF_BIDI) { 586 BUG_ON(!(se_cmd->t_bidi_data_sg && se_cmd->t_bidi_data_nents)); 587 for (i = 0, len = 0; i < se_cmd->t_bidi_data_nents; i++) 588 len += se_cmd->t_bidi_data_sg[i].length; 589 cmd->dbi_bidi_cnt = DIV_ROUND_UP(len, blk_size); 590 cmd->dbi_cnt += cmd->dbi_bidi_cnt; 591 cmd->data_len_bidi = len; 592 } 593 } 594 595 static int new_block_to_iov(struct tcmu_dev *udev, struct tcmu_cmd *cmd, 596 struct iovec **iov, int prev_dbi, int len) 597 { 598 /* Get the next dbi */ 599 int dbi = tcmu_cmd_get_dbi(cmd); 600 601 /* Do not add more than udev->data_blk_size to iov */ 602 len = min_t(int, len, udev->data_blk_size); 603 604 /* 605 * The following code will gather and map the blocks to the same iovec 606 * when the blocks are all next to each other. 607 */ 608 if (dbi != prev_dbi + 1) { 609 /* dbi is not next to previous dbi, so start new iov */ 610 if (prev_dbi >= 0) 611 (*iov)++; 612 /* write offset relative to mb_addr */ 613 (*iov)->iov_base = (void __user *) 614 (udev->data_off + dbi * udev->data_blk_size); 615 } 616 (*iov)->iov_len += len; 617 618 return dbi; 619 } 620 621 static void tcmu_setup_iovs(struct tcmu_dev *udev, struct tcmu_cmd *cmd, 622 struct iovec **iov, int data_length) 623 { 624 /* start value of dbi + 1 must not be a valid dbi */ 625 int dbi = -2; 626 627 /* We prepare the IOVs for DMA_FROM_DEVICE transfer direction */ 628 for (; data_length > 0; data_length -= udev->data_blk_size) 629 dbi = new_block_to_iov(udev, cmd, iov, dbi, data_length); 630 } 631 632 static struct tcmu_cmd *tcmu_alloc_cmd(struct se_cmd *se_cmd) 633 { 634 struct se_device *se_dev = se_cmd->se_dev; 635 struct tcmu_dev *udev = TCMU_DEV(se_dev); 636 struct tcmu_cmd *tcmu_cmd; 637 638 tcmu_cmd = kmem_cache_zalloc(tcmu_cmd_cache, GFP_NOIO); 639 if (!tcmu_cmd) 640 return NULL; 641 642 INIT_LIST_HEAD(&tcmu_cmd->queue_entry); 643 tcmu_cmd->se_cmd = se_cmd; 644 tcmu_cmd->tcmu_dev = udev; 645 646 tcmu_cmd_set_block_cnts(tcmu_cmd); 647 tcmu_cmd->dbi = kcalloc(tcmu_cmd->dbi_cnt, sizeof(uint32_t), 648 GFP_NOIO); 649 if (!tcmu_cmd->dbi) { 650 kmem_cache_free(tcmu_cmd_cache, tcmu_cmd); 651 return NULL; 652 } 653 654 return tcmu_cmd; 655 } 656 657 static inline void tcmu_flush_dcache_range(void *vaddr, size_t size) 658 { 659 unsigned long offset = offset_in_page(vaddr); 660 void *start = vaddr - offset; 661 662 size = round_up(size+offset, PAGE_SIZE); 663 664 while (size) { 665 flush_dcache_page(vmalloc_to_page(start)); 666 start += PAGE_SIZE; 667 size -= PAGE_SIZE; 668 } 669 } 670 671 /* 672 * Some ring helper functions. We don't assume size is a power of 2 so 673 * we can't use circ_buf.h. 674 */ 675 static inline size_t spc_used(size_t head, size_t tail, size_t size) 676 { 677 int diff = head - tail; 678 679 if (diff >= 0) 680 return diff; 681 else 682 return size + diff; 683 } 684 685 static inline size_t spc_free(size_t head, size_t tail, size_t size) 686 { 687 /* Keep 1 byte unused or we can't tell full from empty */ 688 return (size - spc_used(head, tail, size) - 1); 689 } 690 691 static inline size_t head_to_end(size_t head, size_t size) 692 { 693 return size - head; 694 } 695 696 #define UPDATE_HEAD(head, used, size) smp_store_release(&head, ((head % size) + used) % size) 697 698 #define TCMU_SG_TO_DATA_AREA 1 699 #define TCMU_DATA_AREA_TO_SG 2 700 701 static inline void tcmu_copy_data(struct tcmu_dev *udev, 702 struct tcmu_cmd *tcmu_cmd, uint32_t direction, 703 struct scatterlist *sg, unsigned int sg_nents, 704 struct iovec **iov, size_t data_len) 705 { 706 /* start value of dbi + 1 must not be a valid dbi */ 707 int dbi = -2; 708 size_t page_remaining, cp_len; 709 int page_cnt, page_inx, dpi; 710 struct sg_mapping_iter sg_iter; 711 unsigned int sg_flags; 712 struct page *page; 713 void *data_page_start, *data_addr; 714 715 if (direction == TCMU_SG_TO_DATA_AREA) 716 sg_flags = SG_MITER_ATOMIC | SG_MITER_FROM_SG; 717 else 718 sg_flags = SG_MITER_ATOMIC | SG_MITER_TO_SG; 719 sg_miter_start(&sg_iter, sg, sg_nents, sg_flags); 720 721 while (data_len) { 722 if (direction == TCMU_SG_TO_DATA_AREA) 723 dbi = new_block_to_iov(udev, tcmu_cmd, iov, dbi, 724 data_len); 725 else 726 dbi = tcmu_cmd_get_dbi(tcmu_cmd); 727 728 page_cnt = DIV_ROUND_UP(data_len, PAGE_SIZE); 729 if (page_cnt > udev->data_pages_per_blk) 730 page_cnt = udev->data_pages_per_blk; 731 732 dpi = dbi * udev->data_pages_per_blk; 733 for (page_inx = 0; page_inx < page_cnt && data_len; 734 page_inx++, dpi++) { 735 page = xa_load(&udev->data_pages, dpi); 736 737 if (direction == TCMU_DATA_AREA_TO_SG) 738 flush_dcache_page(page); 739 data_page_start = kmap_atomic(page); 740 page_remaining = PAGE_SIZE; 741 742 while (page_remaining && data_len) { 743 if (!sg_miter_next(&sg_iter)) { 744 /* set length to 0 to abort outer loop */ 745 data_len = 0; 746 pr_debug("%s: aborting data copy due to exhausted sg_list\n", 747 __func__); 748 break; 749 } 750 cp_len = min3(sg_iter.length, page_remaining, 751 data_len); 752 753 data_addr = data_page_start + 754 PAGE_SIZE - page_remaining; 755 if (direction == TCMU_SG_TO_DATA_AREA) 756 memcpy(data_addr, sg_iter.addr, cp_len); 757 else 758 memcpy(sg_iter.addr, data_addr, cp_len); 759 760 data_len -= cp_len; 761 page_remaining -= cp_len; 762 sg_iter.consumed = cp_len; 763 } 764 sg_miter_stop(&sg_iter); 765 766 kunmap_atomic(data_page_start); 767 if (direction == TCMU_SG_TO_DATA_AREA) 768 flush_dcache_page(page); 769 } 770 } 771 } 772 773 static void scatter_data_area(struct tcmu_dev *udev, struct tcmu_cmd *tcmu_cmd, 774 struct iovec **iov) 775 { 776 struct se_cmd *se_cmd = tcmu_cmd->se_cmd; 777 778 tcmu_copy_data(udev, tcmu_cmd, TCMU_SG_TO_DATA_AREA, se_cmd->t_data_sg, 779 se_cmd->t_data_nents, iov, se_cmd->data_length); 780 } 781 782 static void gather_data_area(struct tcmu_dev *udev, struct tcmu_cmd *tcmu_cmd, 783 bool bidi, uint32_t read_len) 784 { 785 struct se_cmd *se_cmd = tcmu_cmd->se_cmd; 786 struct scatterlist *data_sg; 787 unsigned int data_nents; 788 789 if (!bidi) { 790 data_sg = se_cmd->t_data_sg; 791 data_nents = se_cmd->t_data_nents; 792 } else { 793 /* 794 * For bidi case, the first count blocks are for Data-Out 795 * buffer blocks, and before gathering the Data-In buffer 796 * the Data-Out buffer blocks should be skipped. 797 */ 798 tcmu_cmd_set_dbi_cur(tcmu_cmd, 799 tcmu_cmd->dbi_cnt - tcmu_cmd->dbi_bidi_cnt); 800 801 data_sg = se_cmd->t_bidi_data_sg; 802 data_nents = se_cmd->t_bidi_data_nents; 803 } 804 805 tcmu_copy_data(udev, tcmu_cmd, TCMU_DATA_AREA_TO_SG, data_sg, 806 data_nents, NULL, read_len); 807 } 808 809 static inline size_t spc_bitmap_free(unsigned long *bitmap, uint32_t thresh) 810 { 811 return thresh - bitmap_weight(bitmap, thresh); 812 } 813 814 /* 815 * We can't queue a command until we have space available on the cmd ring. 816 * 817 * Called with ring lock held. 818 */ 819 static bool is_ring_space_avail(struct tcmu_dev *udev, size_t cmd_size) 820 { 821 struct tcmu_mailbox *mb = udev->mb_addr; 822 size_t space, cmd_needed; 823 u32 cmd_head; 824 825 tcmu_flush_dcache_range(mb, sizeof(*mb)); 826 827 cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ 828 829 /* 830 * If cmd end-of-ring space is too small then we need space for a NOP plus 831 * original cmd - cmds are internally contiguous. 832 */ 833 if (head_to_end(cmd_head, udev->cmdr_size) >= cmd_size) 834 cmd_needed = cmd_size; 835 else 836 cmd_needed = cmd_size + head_to_end(cmd_head, udev->cmdr_size); 837 838 space = spc_free(cmd_head, udev->cmdr_last_cleaned, udev->cmdr_size); 839 if (space < cmd_needed) { 840 pr_debug("no cmd space: %u %u %u\n", cmd_head, 841 udev->cmdr_last_cleaned, udev->cmdr_size); 842 return false; 843 } 844 return true; 845 } 846 847 /* 848 * We have to allocate data buffers before we can queue a command. 849 * Returns -1 on error (not enough space) or number of needed iovs on success 850 * 851 * Called with ring lock held. 852 */ 853 static int tcmu_alloc_data_space(struct tcmu_dev *udev, struct tcmu_cmd *cmd, 854 int *iov_bidi_cnt) 855 { 856 int space, iov_cnt = 0, ret = 0; 857 858 if (!cmd->dbi_cnt) 859 goto wr_iov_cnts; 860 861 /* try to check and get the data blocks as needed */ 862 space = spc_bitmap_free(udev->data_bitmap, udev->dbi_thresh); 863 if (space < cmd->dbi_cnt) { 864 unsigned long blocks_left = 865 (udev->max_blocks - udev->dbi_thresh) + space; 866 867 if (blocks_left < cmd->dbi_cnt) { 868 pr_debug("no data space: only %lu available, but ask for %u\n", 869 blocks_left * udev->data_blk_size, 870 cmd->dbi_cnt * udev->data_blk_size); 871 return -1; 872 } 873 874 udev->dbi_thresh += cmd->dbi_cnt; 875 if (udev->dbi_thresh > udev->max_blocks) 876 udev->dbi_thresh = udev->max_blocks; 877 } 878 879 iov_cnt = tcmu_get_empty_blocks(udev, cmd, cmd->se_cmd->data_length); 880 if (iov_cnt < 0) 881 return -1; 882 883 if (cmd->dbi_bidi_cnt) { 884 ret = tcmu_get_empty_blocks(udev, cmd, cmd->data_len_bidi); 885 if (ret < 0) 886 return -1; 887 } 888 wr_iov_cnts: 889 *iov_bidi_cnt = ret; 890 return iov_cnt + ret; 891 } 892 893 static inline size_t tcmu_cmd_get_base_cmd_size(size_t iov_cnt) 894 { 895 return max(offsetof(struct tcmu_cmd_entry, req.iov[iov_cnt]), 896 sizeof(struct tcmu_cmd_entry)); 897 } 898 899 static inline size_t tcmu_cmd_get_cmd_size(struct tcmu_cmd *tcmu_cmd, 900 size_t base_command_size) 901 { 902 struct se_cmd *se_cmd = tcmu_cmd->se_cmd; 903 size_t command_size; 904 905 command_size = base_command_size + 906 round_up(scsi_command_size(se_cmd->t_task_cdb), 907 TCMU_OP_ALIGN_SIZE); 908 909 WARN_ON(command_size & (TCMU_OP_ALIGN_SIZE-1)); 910 911 return command_size; 912 } 913 914 static void tcmu_setup_cmd_timer(struct tcmu_cmd *tcmu_cmd, unsigned int tmo, 915 struct timer_list *timer) 916 { 917 if (!tmo) 918 return; 919 920 tcmu_cmd->deadline = round_jiffies_up(jiffies + msecs_to_jiffies(tmo)); 921 if (!timer_pending(timer)) 922 mod_timer(timer, tcmu_cmd->deadline); 923 924 pr_debug("Timeout set up for cmd %p, dev = %s, tmo = %lu\n", tcmu_cmd, 925 tcmu_cmd->tcmu_dev->name, tmo / MSEC_PER_SEC); 926 } 927 928 static int add_to_qfull_queue(struct tcmu_cmd *tcmu_cmd) 929 { 930 struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; 931 unsigned int tmo; 932 933 /* 934 * For backwards compat if qfull_time_out is not set use 935 * cmd_time_out and if that's not set use the default time out. 936 */ 937 if (!udev->qfull_time_out) 938 return -ETIMEDOUT; 939 else if (udev->qfull_time_out > 0) 940 tmo = udev->qfull_time_out; 941 else if (udev->cmd_time_out) 942 tmo = udev->cmd_time_out; 943 else 944 tmo = TCMU_TIME_OUT; 945 946 tcmu_setup_cmd_timer(tcmu_cmd, tmo, &udev->qfull_timer); 947 948 list_add_tail(&tcmu_cmd->queue_entry, &udev->qfull_queue); 949 pr_debug("adding cmd %p on dev %s to ring space wait queue\n", 950 tcmu_cmd, udev->name); 951 return 0; 952 } 953 954 static uint32_t ring_insert_padding(struct tcmu_dev *udev, size_t cmd_size) 955 { 956 struct tcmu_cmd_entry_hdr *hdr; 957 struct tcmu_mailbox *mb = udev->mb_addr; 958 uint32_t cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ 959 960 /* Insert a PAD if end-of-ring space is too small */ 961 if (head_to_end(cmd_head, udev->cmdr_size) < cmd_size) { 962 size_t pad_size = head_to_end(cmd_head, udev->cmdr_size); 963 964 hdr = udev->cmdr + cmd_head; 965 tcmu_hdr_set_op(&hdr->len_op, TCMU_OP_PAD); 966 tcmu_hdr_set_len(&hdr->len_op, pad_size); 967 hdr->cmd_id = 0; /* not used for PAD */ 968 hdr->kflags = 0; 969 hdr->uflags = 0; 970 tcmu_flush_dcache_range(hdr, sizeof(*hdr)); 971 972 UPDATE_HEAD(mb->cmd_head, pad_size, udev->cmdr_size); 973 tcmu_flush_dcache_range(mb, sizeof(*mb)); 974 975 cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ 976 WARN_ON(cmd_head != 0); 977 } 978 979 return cmd_head; 980 } 981 982 static void tcmu_unplug_device(struct se_dev_plug *se_plug) 983 { 984 struct se_device *se_dev = se_plug->se_dev; 985 struct tcmu_dev *udev = TCMU_DEV(se_dev); 986 987 clear_bit(TCMU_DEV_BIT_PLUGGED, &udev->flags); 988 uio_event_notify(&udev->uio_info); 989 } 990 991 static struct se_dev_plug *tcmu_plug_device(struct se_device *se_dev) 992 { 993 struct tcmu_dev *udev = TCMU_DEV(se_dev); 994 995 if (!test_and_set_bit(TCMU_DEV_BIT_PLUGGED, &udev->flags)) 996 return &udev->se_plug; 997 998 return NULL; 999 } 1000 1001 /** 1002 * queue_cmd_ring - queue cmd to ring or internally 1003 * @tcmu_cmd: cmd to queue 1004 * @scsi_err: TCM error code if failure (-1) returned. 1005 * 1006 * Returns: 1007 * -1 we cannot queue internally or to the ring. 1008 * 0 success 1009 * 1 internally queued to wait for ring memory to free. 1010 */ 1011 static int queue_cmd_ring(struct tcmu_cmd *tcmu_cmd, sense_reason_t *scsi_err) 1012 { 1013 struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; 1014 struct se_cmd *se_cmd = tcmu_cmd->se_cmd; 1015 size_t base_command_size, command_size; 1016 struct tcmu_mailbox *mb = udev->mb_addr; 1017 struct tcmu_cmd_entry *entry; 1018 struct iovec *iov; 1019 int iov_cnt, iov_bidi_cnt; 1020 uint32_t cmd_id, cmd_head; 1021 uint64_t cdb_off; 1022 uint32_t blk_size = udev->data_blk_size; 1023 /* size of data buffer needed */ 1024 size_t data_length = (size_t)tcmu_cmd->dbi_cnt * blk_size; 1025 1026 *scsi_err = TCM_NO_SENSE; 1027 1028 if (test_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags)) { 1029 *scsi_err = TCM_LUN_BUSY; 1030 return -1; 1031 } 1032 1033 if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) { 1034 *scsi_err = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 1035 return -1; 1036 } 1037 1038 if (!list_empty(&udev->qfull_queue)) 1039 goto queue; 1040 1041 if (data_length > (size_t)udev->max_blocks * blk_size) { 1042 pr_warn("TCMU: Request of size %zu is too big for %zu data area\n", 1043 data_length, (size_t)udev->max_blocks * blk_size); 1044 *scsi_err = TCM_INVALID_CDB_FIELD; 1045 return -1; 1046 } 1047 1048 iov_cnt = tcmu_alloc_data_space(udev, tcmu_cmd, &iov_bidi_cnt); 1049 if (iov_cnt < 0) 1050 goto free_and_queue; 1051 1052 /* 1053 * Must be a certain minimum size for response sense info, but 1054 * also may be larger if the iov array is large. 1055 */ 1056 base_command_size = tcmu_cmd_get_base_cmd_size(iov_cnt); 1057 command_size = tcmu_cmd_get_cmd_size(tcmu_cmd, base_command_size); 1058 1059 if (command_size > (udev->cmdr_size / 2)) { 1060 pr_warn("TCMU: Request of size %zu is too big for %u cmd ring\n", 1061 command_size, udev->cmdr_size); 1062 tcmu_cmd_free_data(tcmu_cmd, tcmu_cmd->dbi_cur); 1063 *scsi_err = TCM_INVALID_CDB_FIELD; 1064 return -1; 1065 } 1066 1067 if (!is_ring_space_avail(udev, command_size)) 1068 /* 1069 * Don't leave commands partially setup because the unmap 1070 * thread might need the blocks to make forward progress. 1071 */ 1072 goto free_and_queue; 1073 1074 if (xa_alloc(&udev->commands, &cmd_id, tcmu_cmd, XA_LIMIT(1, 0xffff), 1075 GFP_NOWAIT) < 0) { 1076 pr_err("tcmu: Could not allocate cmd id.\n"); 1077 1078 tcmu_cmd_free_data(tcmu_cmd, tcmu_cmd->dbi_cnt); 1079 *scsi_err = TCM_OUT_OF_RESOURCES; 1080 return -1; 1081 } 1082 tcmu_cmd->cmd_id = cmd_id; 1083 1084 pr_debug("allocated cmd id %u for cmd %p dev %s\n", tcmu_cmd->cmd_id, 1085 tcmu_cmd, udev->name); 1086 1087 cmd_head = ring_insert_padding(udev, command_size); 1088 1089 entry = udev->cmdr + cmd_head; 1090 memset(entry, 0, command_size); 1091 tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_CMD); 1092 1093 /* prepare iov list and copy data to data area if necessary */ 1094 tcmu_cmd_reset_dbi_cur(tcmu_cmd); 1095 iov = &entry->req.iov[0]; 1096 1097 if (se_cmd->data_direction == DMA_TO_DEVICE || 1098 se_cmd->se_cmd_flags & SCF_BIDI) 1099 scatter_data_area(udev, tcmu_cmd, &iov); 1100 else 1101 tcmu_setup_iovs(udev, tcmu_cmd, &iov, se_cmd->data_length); 1102 1103 entry->req.iov_cnt = iov_cnt - iov_bidi_cnt; 1104 1105 /* Handle BIDI commands */ 1106 if (se_cmd->se_cmd_flags & SCF_BIDI) { 1107 iov++; 1108 tcmu_setup_iovs(udev, tcmu_cmd, &iov, tcmu_cmd->data_len_bidi); 1109 entry->req.iov_bidi_cnt = iov_bidi_cnt; 1110 } 1111 1112 tcmu_setup_cmd_timer(tcmu_cmd, udev->cmd_time_out, &udev->cmd_timer); 1113 1114 entry->hdr.cmd_id = tcmu_cmd->cmd_id; 1115 1116 tcmu_hdr_set_len(&entry->hdr.len_op, command_size); 1117 1118 /* All offsets relative to mb_addr, not start of entry! */ 1119 cdb_off = CMDR_OFF + cmd_head + base_command_size; 1120 memcpy((void *) mb + cdb_off, se_cmd->t_task_cdb, scsi_command_size(se_cmd->t_task_cdb)); 1121 entry->req.cdb_off = cdb_off; 1122 tcmu_flush_dcache_range(entry, command_size); 1123 1124 UPDATE_HEAD(mb->cmd_head, command_size, udev->cmdr_size); 1125 tcmu_flush_dcache_range(mb, sizeof(*mb)); 1126 1127 list_add_tail(&tcmu_cmd->queue_entry, &udev->inflight_queue); 1128 1129 if (!test_bit(TCMU_DEV_BIT_PLUGGED, &udev->flags)) 1130 uio_event_notify(&udev->uio_info); 1131 1132 return 0; 1133 1134 free_and_queue: 1135 tcmu_cmd_free_data(tcmu_cmd, tcmu_cmd->dbi_cur); 1136 tcmu_cmd_reset_dbi_cur(tcmu_cmd); 1137 1138 queue: 1139 if (add_to_qfull_queue(tcmu_cmd)) { 1140 *scsi_err = TCM_OUT_OF_RESOURCES; 1141 return -1; 1142 } 1143 1144 return 1; 1145 } 1146 1147 /** 1148 * queue_tmr_ring - queue tmr info to ring or internally 1149 * @udev: related tcmu_dev 1150 * @tmr: tcmu_tmr containing tmr info to queue 1151 * 1152 * Returns: 1153 * 0 success 1154 * 1 internally queued to wait for ring memory to free. 1155 */ 1156 static int 1157 queue_tmr_ring(struct tcmu_dev *udev, struct tcmu_tmr *tmr) 1158 { 1159 struct tcmu_tmr_entry *entry; 1160 int cmd_size; 1161 int id_list_sz; 1162 struct tcmu_mailbox *mb = udev->mb_addr; 1163 uint32_t cmd_head; 1164 1165 if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) 1166 goto out_free; 1167 1168 id_list_sz = sizeof(tmr->tmr_cmd_ids[0]) * tmr->tmr_cmd_cnt; 1169 cmd_size = round_up(sizeof(*entry) + id_list_sz, TCMU_OP_ALIGN_SIZE); 1170 1171 if (!list_empty(&udev->tmr_queue) || 1172 !is_ring_space_avail(udev, cmd_size)) { 1173 list_add_tail(&tmr->queue_entry, &udev->tmr_queue); 1174 pr_debug("adding tmr %p on dev %s to TMR ring space wait queue\n", 1175 tmr, udev->name); 1176 return 1; 1177 } 1178 1179 cmd_head = ring_insert_padding(udev, cmd_size); 1180 1181 entry = udev->cmdr + cmd_head; 1182 memset(entry, 0, cmd_size); 1183 tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_TMR); 1184 tcmu_hdr_set_len(&entry->hdr.len_op, cmd_size); 1185 entry->tmr_type = tmr->tmr_type; 1186 entry->cmd_cnt = tmr->tmr_cmd_cnt; 1187 memcpy(&entry->cmd_ids[0], &tmr->tmr_cmd_ids[0], id_list_sz); 1188 tcmu_flush_dcache_range(entry, cmd_size); 1189 1190 UPDATE_HEAD(mb->cmd_head, cmd_size, udev->cmdr_size); 1191 tcmu_flush_dcache_range(mb, sizeof(*mb)); 1192 1193 uio_event_notify(&udev->uio_info); 1194 1195 out_free: 1196 kfree(tmr); 1197 1198 return 0; 1199 } 1200 1201 static sense_reason_t 1202 tcmu_queue_cmd(struct se_cmd *se_cmd) 1203 { 1204 struct se_device *se_dev = se_cmd->se_dev; 1205 struct tcmu_dev *udev = TCMU_DEV(se_dev); 1206 struct tcmu_cmd *tcmu_cmd; 1207 sense_reason_t scsi_ret = TCM_CHECK_CONDITION_ABORT_CMD; 1208 int ret = -1; 1209 1210 tcmu_cmd = tcmu_alloc_cmd(se_cmd); 1211 if (!tcmu_cmd) 1212 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 1213 1214 mutex_lock(&udev->cmdr_lock); 1215 if (!(se_cmd->transport_state & CMD_T_ABORTED)) 1216 ret = queue_cmd_ring(tcmu_cmd, &scsi_ret); 1217 if (ret < 0) 1218 tcmu_free_cmd(tcmu_cmd); 1219 else 1220 se_cmd->priv = tcmu_cmd; 1221 mutex_unlock(&udev->cmdr_lock); 1222 return scsi_ret; 1223 } 1224 1225 static void tcmu_set_next_deadline(struct list_head *queue, 1226 struct timer_list *timer) 1227 { 1228 struct tcmu_cmd *cmd; 1229 1230 if (!list_empty(queue)) { 1231 cmd = list_first_entry(queue, struct tcmu_cmd, queue_entry); 1232 mod_timer(timer, cmd->deadline); 1233 } else 1234 del_timer(timer); 1235 } 1236 1237 static int 1238 tcmu_tmr_type(enum tcm_tmreq_table tmf) 1239 { 1240 switch (tmf) { 1241 case TMR_ABORT_TASK: return TCMU_TMR_ABORT_TASK; 1242 case TMR_ABORT_TASK_SET: return TCMU_TMR_ABORT_TASK_SET; 1243 case TMR_CLEAR_ACA: return TCMU_TMR_CLEAR_ACA; 1244 case TMR_CLEAR_TASK_SET: return TCMU_TMR_CLEAR_TASK_SET; 1245 case TMR_LUN_RESET: return TCMU_TMR_LUN_RESET; 1246 case TMR_TARGET_WARM_RESET: return TCMU_TMR_TARGET_WARM_RESET; 1247 case TMR_TARGET_COLD_RESET: return TCMU_TMR_TARGET_COLD_RESET; 1248 case TMR_LUN_RESET_PRO: return TCMU_TMR_LUN_RESET_PRO; 1249 default: return TCMU_TMR_UNKNOWN; 1250 } 1251 } 1252 1253 static void 1254 tcmu_tmr_notify(struct se_device *se_dev, enum tcm_tmreq_table tmf, 1255 struct list_head *cmd_list) 1256 { 1257 int i = 0, cmd_cnt = 0; 1258 bool unqueued = false; 1259 uint16_t *cmd_ids = NULL; 1260 struct tcmu_cmd *cmd; 1261 struct se_cmd *se_cmd; 1262 struct tcmu_tmr *tmr; 1263 struct tcmu_dev *udev = TCMU_DEV(se_dev); 1264 1265 mutex_lock(&udev->cmdr_lock); 1266 1267 /* First we check for aborted commands in qfull_queue */ 1268 list_for_each_entry(se_cmd, cmd_list, state_list) { 1269 i++; 1270 if (!se_cmd->priv) 1271 continue; 1272 cmd = se_cmd->priv; 1273 /* Commands on qfull queue have no id yet */ 1274 if (cmd->cmd_id) { 1275 cmd_cnt++; 1276 continue; 1277 } 1278 pr_debug("Removing aborted command %p from queue on dev %s.\n", 1279 cmd, udev->name); 1280 1281 list_del_init(&cmd->queue_entry); 1282 tcmu_free_cmd(cmd); 1283 se_cmd->priv = NULL; 1284 target_complete_cmd(se_cmd, SAM_STAT_TASK_ABORTED); 1285 unqueued = true; 1286 } 1287 if (unqueued) 1288 tcmu_set_next_deadline(&udev->qfull_queue, &udev->qfull_timer); 1289 1290 if (!test_bit(TCMU_DEV_BIT_TMR_NOTIFY, &udev->flags)) 1291 goto unlock; 1292 1293 pr_debug("TMR event %d on dev %s, aborted cmds %d, afflicted cmd_ids %d\n", 1294 tcmu_tmr_type(tmf), udev->name, i, cmd_cnt); 1295 1296 tmr = kmalloc(sizeof(*tmr) + cmd_cnt * sizeof(*cmd_ids), GFP_NOIO); 1297 if (!tmr) 1298 goto unlock; 1299 1300 tmr->tmr_type = tcmu_tmr_type(tmf); 1301 tmr->tmr_cmd_cnt = cmd_cnt; 1302 1303 if (cmd_cnt != 0) { 1304 cmd_cnt = 0; 1305 list_for_each_entry(se_cmd, cmd_list, state_list) { 1306 if (!se_cmd->priv) 1307 continue; 1308 cmd = se_cmd->priv; 1309 if (cmd->cmd_id) 1310 tmr->tmr_cmd_ids[cmd_cnt++] = cmd->cmd_id; 1311 } 1312 } 1313 1314 queue_tmr_ring(udev, tmr); 1315 1316 unlock: 1317 mutex_unlock(&udev->cmdr_lock); 1318 } 1319 1320 static bool tcmu_handle_completion(struct tcmu_cmd *cmd, 1321 struct tcmu_cmd_entry *entry, bool keep_buf) 1322 { 1323 struct se_cmd *se_cmd = cmd->se_cmd; 1324 struct tcmu_dev *udev = cmd->tcmu_dev; 1325 bool read_len_valid = false; 1326 bool ret = true; 1327 uint32_t read_len; 1328 1329 /* 1330 * cmd has been completed already from timeout, just reclaim 1331 * data area space and free cmd 1332 */ 1333 if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) { 1334 WARN_ON_ONCE(se_cmd); 1335 goto out; 1336 } 1337 if (test_bit(TCMU_CMD_BIT_KEEP_BUF, &cmd->flags)) { 1338 pr_err("cmd_id %u already completed with KEEP_BUF, ring is broken\n", 1339 entry->hdr.cmd_id); 1340 set_bit(TCMU_DEV_BIT_BROKEN, &udev->flags); 1341 ret = false; 1342 goto out; 1343 } 1344 1345 list_del_init(&cmd->queue_entry); 1346 1347 tcmu_cmd_reset_dbi_cur(cmd); 1348 1349 if (entry->hdr.uflags & TCMU_UFLAG_UNKNOWN_OP) { 1350 pr_warn("TCMU: Userspace set UNKNOWN_OP flag on se_cmd %p\n", 1351 cmd->se_cmd); 1352 entry->rsp.scsi_status = SAM_STAT_CHECK_CONDITION; 1353 goto done; 1354 } 1355 1356 read_len = se_cmd->data_length; 1357 if (se_cmd->data_direction == DMA_FROM_DEVICE && 1358 (entry->hdr.uflags & TCMU_UFLAG_READ_LEN) && entry->rsp.read_len) { 1359 read_len_valid = true; 1360 if (entry->rsp.read_len < read_len) 1361 read_len = entry->rsp.read_len; 1362 } 1363 1364 if (entry->rsp.scsi_status == SAM_STAT_CHECK_CONDITION) { 1365 transport_copy_sense_to_cmd(se_cmd, entry->rsp.sense_buffer); 1366 if (!read_len_valid ) 1367 goto done; 1368 else 1369 se_cmd->se_cmd_flags |= SCF_TREAT_READ_AS_NORMAL; 1370 } 1371 if (se_cmd->se_cmd_flags & SCF_BIDI) { 1372 /* Get Data-In buffer before clean up */ 1373 gather_data_area(udev, cmd, true, read_len); 1374 } else if (se_cmd->data_direction == DMA_FROM_DEVICE) { 1375 gather_data_area(udev, cmd, false, read_len); 1376 } else if (se_cmd->data_direction == DMA_TO_DEVICE) { 1377 /* TODO: */ 1378 } else if (se_cmd->data_direction != DMA_NONE) { 1379 pr_warn("TCMU: data direction was %d!\n", 1380 se_cmd->data_direction); 1381 } 1382 1383 done: 1384 se_cmd->priv = NULL; 1385 if (read_len_valid) { 1386 pr_debug("read_len = %d\n", read_len); 1387 target_complete_cmd_with_length(cmd->se_cmd, 1388 entry->rsp.scsi_status, read_len); 1389 } else 1390 target_complete_cmd(cmd->se_cmd, entry->rsp.scsi_status); 1391 1392 out: 1393 if (!keep_buf) { 1394 tcmu_cmd_free_data(cmd, cmd->dbi_cnt); 1395 tcmu_free_cmd(cmd); 1396 } else { 1397 /* 1398 * Keep this command after completion, since userspace still 1399 * needs the data buffer. Mark it with TCMU_CMD_BIT_KEEP_BUF 1400 * and reset potential TCMU_CMD_BIT_EXPIRED, so we don't accept 1401 * a second completion later. 1402 * Userspace can free the buffer later by writing the cmd_id 1403 * to new action attribute free_kept_buf. 1404 */ 1405 clear_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags); 1406 set_bit(TCMU_CMD_BIT_KEEP_BUF, &cmd->flags); 1407 } 1408 return ret; 1409 } 1410 1411 static int tcmu_run_tmr_queue(struct tcmu_dev *udev) 1412 { 1413 struct tcmu_tmr *tmr, *tmp; 1414 LIST_HEAD(tmrs); 1415 1416 if (list_empty(&udev->tmr_queue)) 1417 return 1; 1418 1419 pr_debug("running %s's tmr queue\n", udev->name); 1420 1421 list_splice_init(&udev->tmr_queue, &tmrs); 1422 1423 list_for_each_entry_safe(tmr, tmp, &tmrs, queue_entry) { 1424 list_del_init(&tmr->queue_entry); 1425 1426 pr_debug("removing tmr %p on dev %s from queue\n", 1427 tmr, udev->name); 1428 1429 if (queue_tmr_ring(udev, tmr)) { 1430 pr_debug("ran out of space during tmr queue run\n"); 1431 /* 1432 * tmr was requeued, so just put all tmrs back in 1433 * the queue 1434 */ 1435 list_splice_tail(&tmrs, &udev->tmr_queue); 1436 return 0; 1437 } 1438 } 1439 1440 return 1; 1441 } 1442 1443 static bool tcmu_handle_completions(struct tcmu_dev *udev) 1444 { 1445 struct tcmu_mailbox *mb; 1446 struct tcmu_cmd *cmd; 1447 bool free_space = false; 1448 1449 if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) { 1450 pr_err("ring broken, not handling completions\n"); 1451 return false; 1452 } 1453 1454 mb = udev->mb_addr; 1455 tcmu_flush_dcache_range(mb, sizeof(*mb)); 1456 1457 while (udev->cmdr_last_cleaned != READ_ONCE(mb->cmd_tail)) { 1458 1459 struct tcmu_cmd_entry *entry = udev->cmdr + udev->cmdr_last_cleaned; 1460 bool keep_buf; 1461 1462 /* 1463 * Flush max. up to end of cmd ring since current entry might 1464 * be a padding that is shorter than sizeof(*entry) 1465 */ 1466 size_t ring_left = head_to_end(udev->cmdr_last_cleaned, 1467 udev->cmdr_size); 1468 tcmu_flush_dcache_range(entry, ring_left < sizeof(*entry) ? 1469 ring_left : sizeof(*entry)); 1470 1471 free_space = true; 1472 1473 if (tcmu_hdr_get_op(entry->hdr.len_op) == TCMU_OP_PAD || 1474 tcmu_hdr_get_op(entry->hdr.len_op) == TCMU_OP_TMR) { 1475 UPDATE_HEAD(udev->cmdr_last_cleaned, 1476 tcmu_hdr_get_len(entry->hdr.len_op), 1477 udev->cmdr_size); 1478 continue; 1479 } 1480 WARN_ON(tcmu_hdr_get_op(entry->hdr.len_op) != TCMU_OP_CMD); 1481 1482 keep_buf = !!(entry->hdr.uflags & TCMU_UFLAG_KEEP_BUF); 1483 if (keep_buf) 1484 cmd = xa_load(&udev->commands, entry->hdr.cmd_id); 1485 else 1486 cmd = xa_erase(&udev->commands, entry->hdr.cmd_id); 1487 if (!cmd) { 1488 pr_err("cmd_id %u not found, ring is broken\n", 1489 entry->hdr.cmd_id); 1490 set_bit(TCMU_DEV_BIT_BROKEN, &udev->flags); 1491 return false; 1492 } 1493 1494 if (!tcmu_handle_completion(cmd, entry, keep_buf)) 1495 break; 1496 1497 UPDATE_HEAD(udev->cmdr_last_cleaned, 1498 tcmu_hdr_get_len(entry->hdr.len_op), 1499 udev->cmdr_size); 1500 } 1501 if (free_space) 1502 free_space = tcmu_run_tmr_queue(udev); 1503 1504 if (atomic_read(&global_page_count) > tcmu_global_max_pages && 1505 xa_empty(&udev->commands) && list_empty(&udev->qfull_queue)) { 1506 /* 1507 * Allocated blocks exceeded global block limit, currently no 1508 * more pending or waiting commands so try to reclaim blocks. 1509 */ 1510 schedule_delayed_work(&tcmu_unmap_work, 0); 1511 } 1512 if (udev->cmd_time_out) 1513 tcmu_set_next_deadline(&udev->inflight_queue, &udev->cmd_timer); 1514 1515 return free_space; 1516 } 1517 1518 static void tcmu_check_expired_ring_cmd(struct tcmu_cmd *cmd) 1519 { 1520 struct se_cmd *se_cmd; 1521 1522 if (!time_after_eq(jiffies, cmd->deadline)) 1523 return; 1524 1525 set_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags); 1526 list_del_init(&cmd->queue_entry); 1527 se_cmd = cmd->se_cmd; 1528 se_cmd->priv = NULL; 1529 cmd->se_cmd = NULL; 1530 1531 pr_debug("Timing out inflight cmd %u on dev %s.\n", 1532 cmd->cmd_id, cmd->tcmu_dev->name); 1533 1534 target_complete_cmd(se_cmd, SAM_STAT_CHECK_CONDITION); 1535 } 1536 1537 static void tcmu_check_expired_queue_cmd(struct tcmu_cmd *cmd) 1538 { 1539 struct se_cmd *se_cmd; 1540 1541 if (!time_after_eq(jiffies, cmd->deadline)) 1542 return; 1543 1544 pr_debug("Timing out queued cmd %p on dev %s.\n", 1545 cmd, cmd->tcmu_dev->name); 1546 1547 list_del_init(&cmd->queue_entry); 1548 se_cmd = cmd->se_cmd; 1549 tcmu_free_cmd(cmd); 1550 1551 se_cmd->priv = NULL; 1552 target_complete_cmd(se_cmd, SAM_STAT_TASK_SET_FULL); 1553 } 1554 1555 static void tcmu_device_timedout(struct tcmu_dev *udev) 1556 { 1557 spin_lock(&timed_out_udevs_lock); 1558 if (list_empty(&udev->timedout_entry)) 1559 list_add_tail(&udev->timedout_entry, &timed_out_udevs); 1560 spin_unlock(&timed_out_udevs_lock); 1561 1562 schedule_delayed_work(&tcmu_unmap_work, 0); 1563 } 1564 1565 static void tcmu_cmd_timedout(struct timer_list *t) 1566 { 1567 struct tcmu_dev *udev = from_timer(udev, t, cmd_timer); 1568 1569 pr_debug("%s cmd timeout has expired\n", udev->name); 1570 tcmu_device_timedout(udev); 1571 } 1572 1573 static void tcmu_qfull_timedout(struct timer_list *t) 1574 { 1575 struct tcmu_dev *udev = from_timer(udev, t, qfull_timer); 1576 1577 pr_debug("%s qfull timeout has expired\n", udev->name); 1578 tcmu_device_timedout(udev); 1579 } 1580 1581 static int tcmu_attach_hba(struct se_hba *hba, u32 host_id) 1582 { 1583 struct tcmu_hba *tcmu_hba; 1584 1585 tcmu_hba = kzalloc(sizeof(struct tcmu_hba), GFP_KERNEL); 1586 if (!tcmu_hba) 1587 return -ENOMEM; 1588 1589 tcmu_hba->host_id = host_id; 1590 hba->hba_ptr = tcmu_hba; 1591 1592 return 0; 1593 } 1594 1595 static void tcmu_detach_hba(struct se_hba *hba) 1596 { 1597 kfree(hba->hba_ptr); 1598 hba->hba_ptr = NULL; 1599 } 1600 1601 static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name) 1602 { 1603 struct tcmu_dev *udev; 1604 1605 udev = kzalloc(sizeof(struct tcmu_dev), GFP_KERNEL); 1606 if (!udev) 1607 return NULL; 1608 kref_init(&udev->kref); 1609 1610 udev->name = kstrdup(name, GFP_KERNEL); 1611 if (!udev->name) { 1612 kfree(udev); 1613 return NULL; 1614 } 1615 1616 udev->hba = hba; 1617 udev->cmd_time_out = TCMU_TIME_OUT; 1618 udev->qfull_time_out = -1; 1619 1620 udev->data_pages_per_blk = DATA_PAGES_PER_BLK_DEF; 1621 udev->max_blocks = DATA_AREA_PAGES_DEF / udev->data_pages_per_blk; 1622 udev->data_area_mb = TCMU_PAGES_TO_MBS(DATA_AREA_PAGES_DEF); 1623 1624 mutex_init(&udev->cmdr_lock); 1625 1626 INIT_LIST_HEAD(&udev->node); 1627 INIT_LIST_HEAD(&udev->timedout_entry); 1628 INIT_LIST_HEAD(&udev->qfull_queue); 1629 INIT_LIST_HEAD(&udev->tmr_queue); 1630 INIT_LIST_HEAD(&udev->inflight_queue); 1631 xa_init_flags(&udev->commands, XA_FLAGS_ALLOC1); 1632 1633 timer_setup(&udev->qfull_timer, tcmu_qfull_timedout, 0); 1634 timer_setup(&udev->cmd_timer, tcmu_cmd_timedout, 0); 1635 1636 xa_init(&udev->data_pages); 1637 1638 return &udev->se_dev; 1639 } 1640 1641 static void tcmu_dev_call_rcu(struct rcu_head *p) 1642 { 1643 struct se_device *dev = container_of(p, struct se_device, rcu_head); 1644 struct tcmu_dev *udev = TCMU_DEV(dev); 1645 1646 kfree(udev->uio_info.name); 1647 kfree(udev->name); 1648 kfree(udev); 1649 } 1650 1651 static int tcmu_check_and_free_pending_cmd(struct tcmu_cmd *cmd) 1652 { 1653 if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags) || 1654 test_bit(TCMU_CMD_BIT_KEEP_BUF, &cmd->flags)) { 1655 kmem_cache_free(tcmu_cmd_cache, cmd); 1656 return 0; 1657 } 1658 return -EINVAL; 1659 } 1660 1661 static u32 tcmu_blocks_release(struct tcmu_dev *udev, unsigned long first, 1662 unsigned long last) 1663 { 1664 XA_STATE(xas, &udev->data_pages, first * udev->data_pages_per_blk); 1665 struct page *page; 1666 u32 pages_freed = 0; 1667 1668 xas_lock(&xas); 1669 xas_for_each(&xas, page, (last + 1) * udev->data_pages_per_blk - 1) { 1670 xas_store(&xas, NULL); 1671 /* 1672 * While reaching here there may be page faults occurring on 1673 * the to-be-released pages. A race condition may occur if 1674 * unmap_mapping_range() is called before page faults on these 1675 * pages have completed; a valid but stale map is created. 1676 * 1677 * If another command subsequently runs and needs to extend 1678 * dbi_thresh, it may reuse the slot corresponding to the 1679 * previous page in data_bitmap. Though we will allocate a new 1680 * page for the slot in data_area, no page fault will happen 1681 * because we have a valid map. Therefore the command's data 1682 * will be lost. 1683 * 1684 * We lock and unlock pages that are to be released to ensure 1685 * all page faults have completed. This way 1686 * unmap_mapping_range() can ensure stale maps are cleanly 1687 * removed. 1688 */ 1689 lock_page(page); 1690 unlock_page(page); 1691 __free_page(page); 1692 pages_freed++; 1693 } 1694 xas_unlock(&xas); 1695 1696 atomic_sub(pages_freed, &global_page_count); 1697 1698 return pages_freed; 1699 } 1700 1701 static void tcmu_remove_all_queued_tmr(struct tcmu_dev *udev) 1702 { 1703 struct tcmu_tmr *tmr, *tmp; 1704 1705 list_for_each_entry_safe(tmr, tmp, &udev->tmr_queue, queue_entry) { 1706 list_del_init(&tmr->queue_entry); 1707 kfree(tmr); 1708 } 1709 } 1710 1711 static void tcmu_dev_kref_release(struct kref *kref) 1712 { 1713 struct tcmu_dev *udev = container_of(kref, struct tcmu_dev, kref); 1714 struct se_device *dev = &udev->se_dev; 1715 struct tcmu_cmd *cmd; 1716 bool all_expired = true; 1717 unsigned long i; 1718 1719 vfree(udev->mb_addr); 1720 udev->mb_addr = NULL; 1721 1722 spin_lock_bh(&timed_out_udevs_lock); 1723 if (!list_empty(&udev->timedout_entry)) 1724 list_del(&udev->timedout_entry); 1725 spin_unlock_bh(&timed_out_udevs_lock); 1726 1727 /* Upper layer should drain all requests before calling this */ 1728 mutex_lock(&udev->cmdr_lock); 1729 xa_for_each(&udev->commands, i, cmd) { 1730 if (tcmu_check_and_free_pending_cmd(cmd) != 0) 1731 all_expired = false; 1732 } 1733 /* There can be left over TMR cmds. Remove them. */ 1734 tcmu_remove_all_queued_tmr(udev); 1735 if (!list_empty(&udev->qfull_queue)) 1736 all_expired = false; 1737 xa_destroy(&udev->commands); 1738 WARN_ON(!all_expired); 1739 1740 tcmu_blocks_release(udev, 0, udev->dbi_max); 1741 bitmap_free(udev->data_bitmap); 1742 mutex_unlock(&udev->cmdr_lock); 1743 1744 pr_debug("dev_kref_release\n"); 1745 1746 call_rcu(&dev->rcu_head, tcmu_dev_call_rcu); 1747 } 1748 1749 static void run_qfull_queue(struct tcmu_dev *udev, bool fail) 1750 { 1751 struct tcmu_cmd *tcmu_cmd, *tmp_cmd; 1752 LIST_HEAD(cmds); 1753 sense_reason_t scsi_ret; 1754 int ret; 1755 1756 if (list_empty(&udev->qfull_queue)) 1757 return; 1758 1759 pr_debug("running %s's cmdr queue forcefail %d\n", udev->name, fail); 1760 1761 list_splice_init(&udev->qfull_queue, &cmds); 1762 1763 list_for_each_entry_safe(tcmu_cmd, tmp_cmd, &cmds, queue_entry) { 1764 list_del_init(&tcmu_cmd->queue_entry); 1765 1766 pr_debug("removing cmd %p on dev %s from queue\n", 1767 tcmu_cmd, udev->name); 1768 1769 if (fail) { 1770 /* 1771 * We were not able to even start the command, so 1772 * fail with busy to allow a retry in case runner 1773 * was only temporarily down. If the device is being 1774 * removed then LIO core will do the right thing and 1775 * fail the retry. 1776 */ 1777 tcmu_cmd->se_cmd->priv = NULL; 1778 target_complete_cmd(tcmu_cmd->se_cmd, SAM_STAT_BUSY); 1779 tcmu_free_cmd(tcmu_cmd); 1780 continue; 1781 } 1782 1783 ret = queue_cmd_ring(tcmu_cmd, &scsi_ret); 1784 if (ret < 0) { 1785 pr_debug("cmd %p on dev %s failed with %u\n", 1786 tcmu_cmd, udev->name, scsi_ret); 1787 /* 1788 * Ignore scsi_ret for now. target_complete_cmd 1789 * drops it. 1790 */ 1791 tcmu_cmd->se_cmd->priv = NULL; 1792 target_complete_cmd(tcmu_cmd->se_cmd, 1793 SAM_STAT_CHECK_CONDITION); 1794 tcmu_free_cmd(tcmu_cmd); 1795 } else if (ret > 0) { 1796 pr_debug("ran out of space during cmdr queue run\n"); 1797 /* 1798 * cmd was requeued, so just put all cmds back in 1799 * the queue 1800 */ 1801 list_splice_tail(&cmds, &udev->qfull_queue); 1802 break; 1803 } 1804 } 1805 1806 tcmu_set_next_deadline(&udev->qfull_queue, &udev->qfull_timer); 1807 } 1808 1809 static int tcmu_irqcontrol(struct uio_info *info, s32 irq_on) 1810 { 1811 struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); 1812 1813 mutex_lock(&udev->cmdr_lock); 1814 if (tcmu_handle_completions(udev)) 1815 run_qfull_queue(udev, false); 1816 mutex_unlock(&udev->cmdr_lock); 1817 1818 return 0; 1819 } 1820 1821 /* 1822 * mmap code from uio.c. Copied here because we want to hook mmap() 1823 * and this stuff must come along. 1824 */ 1825 static int tcmu_find_mem_index(struct vm_area_struct *vma) 1826 { 1827 struct tcmu_dev *udev = vma->vm_private_data; 1828 struct uio_info *info = &udev->uio_info; 1829 1830 if (vma->vm_pgoff < MAX_UIO_MAPS) { 1831 if (info->mem[vma->vm_pgoff].size == 0) 1832 return -1; 1833 return (int)vma->vm_pgoff; 1834 } 1835 return -1; 1836 } 1837 1838 static struct page *tcmu_try_get_data_page(struct tcmu_dev *udev, uint32_t dpi) 1839 { 1840 struct page *page; 1841 1842 mutex_lock(&udev->cmdr_lock); 1843 page = xa_load(&udev->data_pages, dpi); 1844 if (likely(page)) { 1845 get_page(page); 1846 lock_page(page); 1847 mutex_unlock(&udev->cmdr_lock); 1848 return page; 1849 } 1850 1851 /* 1852 * Userspace messed up and passed in a address not in the 1853 * data iov passed to it. 1854 */ 1855 pr_err("Invalid addr to data page mapping (dpi %u) on device %s\n", 1856 dpi, udev->name); 1857 mutex_unlock(&udev->cmdr_lock); 1858 1859 return NULL; 1860 } 1861 1862 static void tcmu_vma_open(struct vm_area_struct *vma) 1863 { 1864 struct tcmu_dev *udev = vma->vm_private_data; 1865 1866 pr_debug("vma_open\n"); 1867 1868 kref_get(&udev->kref); 1869 } 1870 1871 static void tcmu_vma_close(struct vm_area_struct *vma) 1872 { 1873 struct tcmu_dev *udev = vma->vm_private_data; 1874 1875 pr_debug("vma_close\n"); 1876 1877 /* release ref from tcmu_vma_open */ 1878 kref_put(&udev->kref, tcmu_dev_kref_release); 1879 } 1880 1881 static vm_fault_t tcmu_vma_fault(struct vm_fault *vmf) 1882 { 1883 struct tcmu_dev *udev = vmf->vma->vm_private_data; 1884 struct uio_info *info = &udev->uio_info; 1885 struct page *page; 1886 unsigned long offset; 1887 void *addr; 1888 vm_fault_t ret = 0; 1889 1890 int mi = tcmu_find_mem_index(vmf->vma); 1891 if (mi < 0) 1892 return VM_FAULT_SIGBUS; 1893 1894 /* 1895 * We need to subtract mi because userspace uses offset = N*PAGE_SIZE 1896 * to use mem[N]. 1897 */ 1898 offset = (vmf->pgoff - mi) << PAGE_SHIFT; 1899 1900 if (offset < udev->data_off) { 1901 /* For the vmalloc()ed cmd area pages */ 1902 addr = (void *)(unsigned long)info->mem[mi].addr + offset; 1903 page = vmalloc_to_page(addr); 1904 get_page(page); 1905 } else { 1906 uint32_t dpi; 1907 1908 /* For the dynamically growing data area pages */ 1909 dpi = (offset - udev->data_off) / PAGE_SIZE; 1910 page = tcmu_try_get_data_page(udev, dpi); 1911 if (!page) 1912 return VM_FAULT_SIGBUS; 1913 ret = VM_FAULT_LOCKED; 1914 } 1915 1916 vmf->page = page; 1917 return ret; 1918 } 1919 1920 static const struct vm_operations_struct tcmu_vm_ops = { 1921 .open = tcmu_vma_open, 1922 .close = tcmu_vma_close, 1923 .fault = tcmu_vma_fault, 1924 }; 1925 1926 static int tcmu_mmap(struct uio_info *info, struct vm_area_struct *vma) 1927 { 1928 struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); 1929 1930 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; 1931 vma->vm_ops = &tcmu_vm_ops; 1932 1933 vma->vm_private_data = udev; 1934 1935 /* Ensure the mmap is exactly the right size */ 1936 if (vma_pages(vma) != udev->mmap_pages) 1937 return -EINVAL; 1938 1939 tcmu_vma_open(vma); 1940 1941 return 0; 1942 } 1943 1944 static int tcmu_open(struct uio_info *info, struct inode *inode) 1945 { 1946 struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); 1947 1948 /* O_EXCL not supported for char devs, so fake it? */ 1949 if (test_and_set_bit(TCMU_DEV_BIT_OPEN, &udev->flags)) 1950 return -EBUSY; 1951 1952 udev->inode = inode; 1953 1954 pr_debug("open\n"); 1955 1956 return 0; 1957 } 1958 1959 static int tcmu_release(struct uio_info *info, struct inode *inode) 1960 { 1961 struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); 1962 struct tcmu_cmd *cmd; 1963 unsigned long i; 1964 bool freed = false; 1965 1966 mutex_lock(&udev->cmdr_lock); 1967 1968 xa_for_each(&udev->commands, i, cmd) { 1969 /* Cmds with KEEP_BUF set are no longer on the ring, but 1970 * userspace still holds the data buffer. If userspace closes 1971 * we implicitly free these cmds and buffers, since after new 1972 * open the (new ?) userspace cannot find the cmd in the ring 1973 * and thus never will release the buffer by writing cmd_id to 1974 * free_kept_buf action attribute. 1975 */ 1976 if (!test_bit(TCMU_CMD_BIT_KEEP_BUF, &cmd->flags)) 1977 continue; 1978 pr_debug("removing KEEP_BUF cmd %u on dev %s from ring\n", 1979 cmd->cmd_id, udev->name); 1980 freed = true; 1981 1982 xa_erase(&udev->commands, i); 1983 tcmu_cmd_free_data(cmd, cmd->dbi_cnt); 1984 tcmu_free_cmd(cmd); 1985 } 1986 /* 1987 * We only freed data space, not ring space. Therefore we dont call 1988 * run_tmr_queue, but call run_qfull_queue if tmr_list is empty. 1989 */ 1990 if (freed && list_empty(&udev->tmr_queue)) 1991 run_qfull_queue(udev, false); 1992 1993 mutex_unlock(&udev->cmdr_lock); 1994 1995 clear_bit(TCMU_DEV_BIT_OPEN, &udev->flags); 1996 1997 pr_debug("close\n"); 1998 1999 return 0; 2000 } 2001 2002 static int tcmu_init_genl_cmd_reply(struct tcmu_dev *udev, int cmd) 2003 { 2004 struct tcmu_nl_cmd *nl_cmd = &udev->curr_nl_cmd; 2005 2006 if (!tcmu_kern_cmd_reply_supported) 2007 return 0; 2008 2009 if (udev->nl_reply_supported <= 0) 2010 return 0; 2011 2012 mutex_lock(&tcmu_nl_cmd_mutex); 2013 2014 if (tcmu_netlink_blocked) { 2015 mutex_unlock(&tcmu_nl_cmd_mutex); 2016 pr_warn("Failing nl cmd %d on %s. Interface is blocked.\n", cmd, 2017 udev->name); 2018 return -EAGAIN; 2019 } 2020 2021 if (nl_cmd->cmd != TCMU_CMD_UNSPEC) { 2022 mutex_unlock(&tcmu_nl_cmd_mutex); 2023 pr_warn("netlink cmd %d already executing on %s\n", 2024 nl_cmd->cmd, udev->name); 2025 return -EBUSY; 2026 } 2027 2028 memset(nl_cmd, 0, sizeof(*nl_cmd)); 2029 nl_cmd->cmd = cmd; 2030 nl_cmd->udev = udev; 2031 init_completion(&nl_cmd->complete); 2032 INIT_LIST_HEAD(&nl_cmd->nl_list); 2033 2034 list_add_tail(&nl_cmd->nl_list, &tcmu_nl_cmd_list); 2035 2036 mutex_unlock(&tcmu_nl_cmd_mutex); 2037 return 0; 2038 } 2039 2040 static void tcmu_destroy_genl_cmd_reply(struct tcmu_dev *udev) 2041 { 2042 struct tcmu_nl_cmd *nl_cmd = &udev->curr_nl_cmd; 2043 2044 if (!tcmu_kern_cmd_reply_supported) 2045 return; 2046 2047 if (udev->nl_reply_supported <= 0) 2048 return; 2049 2050 mutex_lock(&tcmu_nl_cmd_mutex); 2051 2052 list_del(&nl_cmd->nl_list); 2053 memset(nl_cmd, 0, sizeof(*nl_cmd)); 2054 2055 mutex_unlock(&tcmu_nl_cmd_mutex); 2056 } 2057 2058 static int tcmu_wait_genl_cmd_reply(struct tcmu_dev *udev) 2059 { 2060 struct tcmu_nl_cmd *nl_cmd = &udev->curr_nl_cmd; 2061 int ret; 2062 2063 if (!tcmu_kern_cmd_reply_supported) 2064 return 0; 2065 2066 if (udev->nl_reply_supported <= 0) 2067 return 0; 2068 2069 pr_debug("sleeping for nl reply\n"); 2070 wait_for_completion(&nl_cmd->complete); 2071 2072 mutex_lock(&tcmu_nl_cmd_mutex); 2073 nl_cmd->cmd = TCMU_CMD_UNSPEC; 2074 ret = nl_cmd->status; 2075 mutex_unlock(&tcmu_nl_cmd_mutex); 2076 2077 return ret; 2078 } 2079 2080 static int tcmu_netlink_event_init(struct tcmu_dev *udev, 2081 enum tcmu_genl_cmd cmd, 2082 struct sk_buff **buf, void **hdr) 2083 { 2084 struct sk_buff *skb; 2085 void *msg_header; 2086 int ret = -ENOMEM; 2087 2088 skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); 2089 if (!skb) 2090 return ret; 2091 2092 msg_header = genlmsg_put(skb, 0, 0, &tcmu_genl_family, 0, cmd); 2093 if (!msg_header) 2094 goto free_skb; 2095 2096 ret = nla_put_string(skb, TCMU_ATTR_DEVICE, udev->uio_info.name); 2097 if (ret < 0) 2098 goto free_skb; 2099 2100 ret = nla_put_u32(skb, TCMU_ATTR_MINOR, udev->uio_info.uio_dev->minor); 2101 if (ret < 0) 2102 goto free_skb; 2103 2104 ret = nla_put_u32(skb, TCMU_ATTR_DEVICE_ID, udev->se_dev.dev_index); 2105 if (ret < 0) 2106 goto free_skb; 2107 2108 *buf = skb; 2109 *hdr = msg_header; 2110 return ret; 2111 2112 free_skb: 2113 nlmsg_free(skb); 2114 return ret; 2115 } 2116 2117 static int tcmu_netlink_event_send(struct tcmu_dev *udev, 2118 enum tcmu_genl_cmd cmd, 2119 struct sk_buff *skb, void *msg_header) 2120 { 2121 int ret; 2122 2123 genlmsg_end(skb, msg_header); 2124 2125 ret = tcmu_init_genl_cmd_reply(udev, cmd); 2126 if (ret) { 2127 nlmsg_free(skb); 2128 return ret; 2129 } 2130 2131 ret = genlmsg_multicast_allns(&tcmu_genl_family, skb, 0, 2132 TCMU_MCGRP_CONFIG, GFP_KERNEL); 2133 2134 /* Wait during an add as the listener may not be up yet */ 2135 if (ret == 0 || 2136 (ret == -ESRCH && cmd == TCMU_CMD_ADDED_DEVICE)) 2137 return tcmu_wait_genl_cmd_reply(udev); 2138 else 2139 tcmu_destroy_genl_cmd_reply(udev); 2140 2141 return ret; 2142 } 2143 2144 static int tcmu_send_dev_add_event(struct tcmu_dev *udev) 2145 { 2146 struct sk_buff *skb = NULL; 2147 void *msg_header = NULL; 2148 int ret = 0; 2149 2150 ret = tcmu_netlink_event_init(udev, TCMU_CMD_ADDED_DEVICE, &skb, 2151 &msg_header); 2152 if (ret < 0) 2153 return ret; 2154 return tcmu_netlink_event_send(udev, TCMU_CMD_ADDED_DEVICE, skb, 2155 msg_header); 2156 } 2157 2158 static int tcmu_send_dev_remove_event(struct tcmu_dev *udev) 2159 { 2160 struct sk_buff *skb = NULL; 2161 void *msg_header = NULL; 2162 int ret = 0; 2163 2164 ret = tcmu_netlink_event_init(udev, TCMU_CMD_REMOVED_DEVICE, 2165 &skb, &msg_header); 2166 if (ret < 0) 2167 return ret; 2168 return tcmu_netlink_event_send(udev, TCMU_CMD_REMOVED_DEVICE, 2169 skb, msg_header); 2170 } 2171 2172 static int tcmu_update_uio_info(struct tcmu_dev *udev) 2173 { 2174 struct tcmu_hba *hba = udev->hba->hba_ptr; 2175 struct uio_info *info; 2176 char *str; 2177 2178 info = &udev->uio_info; 2179 2180 if (udev->dev_config[0]) 2181 str = kasprintf(GFP_KERNEL, "tcm-user/%u/%s/%s", hba->host_id, 2182 udev->name, udev->dev_config); 2183 else 2184 str = kasprintf(GFP_KERNEL, "tcm-user/%u/%s", hba->host_id, 2185 udev->name); 2186 if (!str) 2187 return -ENOMEM; 2188 2189 /* If the old string exists, free it */ 2190 kfree(info->name); 2191 info->name = str; 2192 2193 return 0; 2194 } 2195 2196 static int tcmu_configure_device(struct se_device *dev) 2197 { 2198 struct tcmu_dev *udev = TCMU_DEV(dev); 2199 struct uio_info *info; 2200 struct tcmu_mailbox *mb; 2201 size_t data_size; 2202 int ret = 0; 2203 2204 ret = tcmu_update_uio_info(udev); 2205 if (ret) 2206 return ret; 2207 2208 info = &udev->uio_info; 2209 2210 mutex_lock(&udev->cmdr_lock); 2211 udev->data_bitmap = bitmap_zalloc(udev->max_blocks, GFP_KERNEL); 2212 mutex_unlock(&udev->cmdr_lock); 2213 if (!udev->data_bitmap) { 2214 ret = -ENOMEM; 2215 goto err_bitmap_alloc; 2216 } 2217 2218 mb = vzalloc(MB_CMDR_SIZE); 2219 if (!mb) { 2220 ret = -ENOMEM; 2221 goto err_vzalloc; 2222 } 2223 2224 /* mailbox fits in first part of CMDR space */ 2225 udev->mb_addr = mb; 2226 udev->cmdr = (void *)mb + CMDR_OFF; 2227 udev->cmdr_size = CMDR_SIZE; 2228 udev->data_off = MB_CMDR_SIZE; 2229 data_size = TCMU_MBS_TO_PAGES(udev->data_area_mb) << PAGE_SHIFT; 2230 udev->mmap_pages = (data_size + MB_CMDR_SIZE) >> PAGE_SHIFT; 2231 udev->data_blk_size = udev->data_pages_per_blk * PAGE_SIZE; 2232 udev->dbi_thresh = 0; /* Default in Idle state */ 2233 2234 /* Initialise the mailbox of the ring buffer */ 2235 mb->version = TCMU_MAILBOX_VERSION; 2236 mb->flags = TCMU_MAILBOX_FLAG_CAP_OOOC | 2237 TCMU_MAILBOX_FLAG_CAP_READ_LEN | 2238 TCMU_MAILBOX_FLAG_CAP_TMR | 2239 TCMU_MAILBOX_FLAG_CAP_KEEP_BUF; 2240 mb->cmdr_off = CMDR_OFF; 2241 mb->cmdr_size = udev->cmdr_size; 2242 2243 WARN_ON(!PAGE_ALIGNED(udev->data_off)); 2244 WARN_ON(data_size % PAGE_SIZE); 2245 2246 info->version = __stringify(TCMU_MAILBOX_VERSION); 2247 2248 info->mem[0].name = "tcm-user command & data buffer"; 2249 info->mem[0].addr = (phys_addr_t)(uintptr_t)udev->mb_addr; 2250 info->mem[0].size = data_size + MB_CMDR_SIZE; 2251 info->mem[0].memtype = UIO_MEM_NONE; 2252 2253 info->irqcontrol = tcmu_irqcontrol; 2254 info->irq = UIO_IRQ_CUSTOM; 2255 2256 info->mmap = tcmu_mmap; 2257 info->open = tcmu_open; 2258 info->release = tcmu_release; 2259 2260 ret = uio_register_device(tcmu_root_device, info); 2261 if (ret) 2262 goto err_register; 2263 2264 /* User can set hw_block_size before enable the device */ 2265 if (dev->dev_attrib.hw_block_size == 0) 2266 dev->dev_attrib.hw_block_size = 512; 2267 /* Other attributes can be configured in userspace */ 2268 if (!dev->dev_attrib.hw_max_sectors) 2269 dev->dev_attrib.hw_max_sectors = 128; 2270 if (!dev->dev_attrib.emulate_write_cache) 2271 dev->dev_attrib.emulate_write_cache = 0; 2272 dev->dev_attrib.hw_queue_depth = 128; 2273 2274 /* If user didn't explicitly disable netlink reply support, use 2275 * module scope setting. 2276 */ 2277 if (udev->nl_reply_supported >= 0) 2278 udev->nl_reply_supported = tcmu_kern_cmd_reply_supported; 2279 2280 /* 2281 * Get a ref incase userspace does a close on the uio device before 2282 * LIO has initiated tcmu_free_device. 2283 */ 2284 kref_get(&udev->kref); 2285 2286 ret = tcmu_send_dev_add_event(udev); 2287 if (ret) 2288 goto err_netlink; 2289 2290 mutex_lock(&root_udev_mutex); 2291 list_add(&udev->node, &root_udev); 2292 mutex_unlock(&root_udev_mutex); 2293 2294 return 0; 2295 2296 err_netlink: 2297 kref_put(&udev->kref, tcmu_dev_kref_release); 2298 uio_unregister_device(&udev->uio_info); 2299 err_register: 2300 vfree(udev->mb_addr); 2301 udev->mb_addr = NULL; 2302 err_vzalloc: 2303 bitmap_free(udev->data_bitmap); 2304 udev->data_bitmap = NULL; 2305 err_bitmap_alloc: 2306 kfree(info->name); 2307 info->name = NULL; 2308 2309 return ret; 2310 } 2311 2312 static void tcmu_free_device(struct se_device *dev) 2313 { 2314 struct tcmu_dev *udev = TCMU_DEV(dev); 2315 2316 /* release ref from init */ 2317 kref_put(&udev->kref, tcmu_dev_kref_release); 2318 } 2319 2320 static void tcmu_destroy_device(struct se_device *dev) 2321 { 2322 struct tcmu_dev *udev = TCMU_DEV(dev); 2323 2324 del_timer_sync(&udev->cmd_timer); 2325 del_timer_sync(&udev->qfull_timer); 2326 2327 mutex_lock(&root_udev_mutex); 2328 list_del(&udev->node); 2329 mutex_unlock(&root_udev_mutex); 2330 2331 tcmu_send_dev_remove_event(udev); 2332 2333 uio_unregister_device(&udev->uio_info); 2334 2335 /* release ref from configure */ 2336 kref_put(&udev->kref, tcmu_dev_kref_release); 2337 } 2338 2339 static void tcmu_unblock_dev(struct tcmu_dev *udev) 2340 { 2341 mutex_lock(&udev->cmdr_lock); 2342 clear_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags); 2343 mutex_unlock(&udev->cmdr_lock); 2344 } 2345 2346 static void tcmu_block_dev(struct tcmu_dev *udev) 2347 { 2348 mutex_lock(&udev->cmdr_lock); 2349 2350 if (test_and_set_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags)) 2351 goto unlock; 2352 2353 /* complete IO that has executed successfully */ 2354 tcmu_handle_completions(udev); 2355 /* fail IO waiting to be queued */ 2356 run_qfull_queue(udev, true); 2357 2358 unlock: 2359 mutex_unlock(&udev->cmdr_lock); 2360 } 2361 2362 static void tcmu_reset_ring(struct tcmu_dev *udev, u8 err_level) 2363 { 2364 struct tcmu_mailbox *mb; 2365 struct tcmu_cmd *cmd; 2366 unsigned long i; 2367 2368 mutex_lock(&udev->cmdr_lock); 2369 2370 xa_for_each(&udev->commands, i, cmd) { 2371 pr_debug("removing cmd %u on dev %s from ring %s\n", 2372 cmd->cmd_id, udev->name, 2373 test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags) ? 2374 "(is expired)" : 2375 (test_bit(TCMU_CMD_BIT_KEEP_BUF, &cmd->flags) ? 2376 "(is keep buffer)" : "")); 2377 2378 xa_erase(&udev->commands, i); 2379 if (!test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags) && 2380 !test_bit(TCMU_CMD_BIT_KEEP_BUF, &cmd->flags)) { 2381 WARN_ON(!cmd->se_cmd); 2382 list_del_init(&cmd->queue_entry); 2383 cmd->se_cmd->priv = NULL; 2384 if (err_level == 1) { 2385 /* 2386 * Userspace was not able to start the 2387 * command or it is retryable. 2388 */ 2389 target_complete_cmd(cmd->se_cmd, SAM_STAT_BUSY); 2390 } else { 2391 /* hard failure */ 2392 target_complete_cmd(cmd->se_cmd, 2393 SAM_STAT_CHECK_CONDITION); 2394 } 2395 } 2396 tcmu_cmd_free_data(cmd, cmd->dbi_cnt); 2397 tcmu_free_cmd(cmd); 2398 } 2399 2400 mb = udev->mb_addr; 2401 tcmu_flush_dcache_range(mb, sizeof(*mb)); 2402 pr_debug("mb last %u head %u tail %u\n", udev->cmdr_last_cleaned, 2403 mb->cmd_tail, mb->cmd_head); 2404 2405 udev->cmdr_last_cleaned = 0; 2406 mb->cmd_tail = 0; 2407 mb->cmd_head = 0; 2408 tcmu_flush_dcache_range(mb, sizeof(*mb)); 2409 clear_bit(TCMU_DEV_BIT_BROKEN, &udev->flags); 2410 2411 del_timer(&udev->cmd_timer); 2412 2413 /* 2414 * ring is empty and qfull queue never contains aborted commands. 2415 * So TMRs in tmr queue do not contain relevant cmd_ids. 2416 * After a ring reset userspace should do a fresh start, so 2417 * even LUN RESET message is no longer relevant. 2418 * Therefore remove all TMRs from qfull queue 2419 */ 2420 tcmu_remove_all_queued_tmr(udev); 2421 2422 run_qfull_queue(udev, false); 2423 2424 mutex_unlock(&udev->cmdr_lock); 2425 } 2426 2427 enum { 2428 Opt_dev_config, Opt_dev_size, Opt_hw_block_size, Opt_hw_max_sectors, 2429 Opt_nl_reply_supported, Opt_max_data_area_mb, Opt_data_pages_per_blk, 2430 Opt_err, 2431 }; 2432 2433 static match_table_t tokens = { 2434 {Opt_dev_config, "dev_config=%s"}, 2435 {Opt_dev_size, "dev_size=%s"}, 2436 {Opt_hw_block_size, "hw_block_size=%d"}, 2437 {Opt_hw_max_sectors, "hw_max_sectors=%d"}, 2438 {Opt_nl_reply_supported, "nl_reply_supported=%d"}, 2439 {Opt_max_data_area_mb, "max_data_area_mb=%d"}, 2440 {Opt_data_pages_per_blk, "data_pages_per_blk=%d"}, 2441 {Opt_err, NULL} 2442 }; 2443 2444 static int tcmu_set_dev_attrib(substring_t *arg, u32 *dev_attrib) 2445 { 2446 int val, ret; 2447 2448 ret = match_int(arg, &val); 2449 if (ret < 0) { 2450 pr_err("match_int() failed for dev attrib. Error %d.\n", 2451 ret); 2452 return ret; 2453 } 2454 2455 if (val <= 0) { 2456 pr_err("Invalid dev attrib value %d. Must be greater than zero.\n", 2457 val); 2458 return -EINVAL; 2459 } 2460 *dev_attrib = val; 2461 return 0; 2462 } 2463 2464 static int tcmu_set_max_blocks_param(struct tcmu_dev *udev, substring_t *arg) 2465 { 2466 int val, ret; 2467 uint32_t pages_per_blk = udev->data_pages_per_blk; 2468 2469 ret = match_int(arg, &val); 2470 if (ret < 0) { 2471 pr_err("match_int() failed for max_data_area_mb=. Error %d.\n", 2472 ret); 2473 return ret; 2474 } 2475 if (val <= 0) { 2476 pr_err("Invalid max_data_area %d.\n", val); 2477 return -EINVAL; 2478 } 2479 if (val > TCMU_PAGES_TO_MBS(tcmu_global_max_pages)) { 2480 pr_err("%d is too large. Adjusting max_data_area_mb to global limit of %u\n", 2481 val, TCMU_PAGES_TO_MBS(tcmu_global_max_pages)); 2482 val = TCMU_PAGES_TO_MBS(tcmu_global_max_pages); 2483 } 2484 if (TCMU_MBS_TO_PAGES(val) < pages_per_blk) { 2485 pr_err("Invalid max_data_area %d (%zu pages): smaller than data_pages_per_blk (%u pages).\n", 2486 val, TCMU_MBS_TO_PAGES(val), pages_per_blk); 2487 return -EINVAL; 2488 } 2489 2490 mutex_lock(&udev->cmdr_lock); 2491 if (udev->data_bitmap) { 2492 pr_err("Cannot set max_data_area_mb after it has been enabled.\n"); 2493 ret = -EINVAL; 2494 goto unlock; 2495 } 2496 2497 udev->data_area_mb = val; 2498 udev->max_blocks = TCMU_MBS_TO_PAGES(val) / pages_per_blk; 2499 2500 unlock: 2501 mutex_unlock(&udev->cmdr_lock); 2502 return ret; 2503 } 2504 2505 static int tcmu_set_data_pages_per_blk(struct tcmu_dev *udev, substring_t *arg) 2506 { 2507 int val, ret; 2508 2509 ret = match_int(arg, &val); 2510 if (ret < 0) { 2511 pr_err("match_int() failed for data_pages_per_blk=. Error %d.\n", 2512 ret); 2513 return ret; 2514 } 2515 2516 if (val > TCMU_MBS_TO_PAGES(udev->data_area_mb)) { 2517 pr_err("Invalid data_pages_per_blk %d: greater than max_data_area_mb %d -> %zd pages).\n", 2518 val, udev->data_area_mb, 2519 TCMU_MBS_TO_PAGES(udev->data_area_mb)); 2520 return -EINVAL; 2521 } 2522 2523 mutex_lock(&udev->cmdr_lock); 2524 if (udev->data_bitmap) { 2525 pr_err("Cannot set data_pages_per_blk after it has been enabled.\n"); 2526 ret = -EINVAL; 2527 goto unlock; 2528 } 2529 2530 udev->data_pages_per_blk = val; 2531 udev->max_blocks = TCMU_MBS_TO_PAGES(udev->data_area_mb) / val; 2532 2533 unlock: 2534 mutex_unlock(&udev->cmdr_lock); 2535 return ret; 2536 } 2537 2538 static ssize_t tcmu_set_configfs_dev_params(struct se_device *dev, 2539 const char *page, ssize_t count) 2540 { 2541 struct tcmu_dev *udev = TCMU_DEV(dev); 2542 char *orig, *ptr, *opts; 2543 substring_t args[MAX_OPT_ARGS]; 2544 int ret = 0, token; 2545 2546 opts = kstrdup(page, GFP_KERNEL); 2547 if (!opts) 2548 return -ENOMEM; 2549 2550 orig = opts; 2551 2552 while ((ptr = strsep(&opts, ",\n")) != NULL) { 2553 if (!*ptr) 2554 continue; 2555 2556 token = match_token(ptr, tokens, args); 2557 switch (token) { 2558 case Opt_dev_config: 2559 if (match_strlcpy(udev->dev_config, &args[0], 2560 TCMU_CONFIG_LEN) == 0) { 2561 ret = -EINVAL; 2562 break; 2563 } 2564 pr_debug("TCMU: Referencing Path: %s\n", udev->dev_config); 2565 break; 2566 case Opt_dev_size: 2567 ret = match_u64(&args[0], &udev->dev_size); 2568 if (ret < 0) 2569 pr_err("match_u64() failed for dev_size=. Error %d.\n", 2570 ret); 2571 break; 2572 case Opt_hw_block_size: 2573 ret = tcmu_set_dev_attrib(&args[0], 2574 &(dev->dev_attrib.hw_block_size)); 2575 break; 2576 case Opt_hw_max_sectors: 2577 ret = tcmu_set_dev_attrib(&args[0], 2578 &(dev->dev_attrib.hw_max_sectors)); 2579 break; 2580 case Opt_nl_reply_supported: 2581 ret = match_int(&args[0], &udev->nl_reply_supported); 2582 if (ret < 0) 2583 pr_err("match_int() failed for nl_reply_supported=. Error %d.\n", 2584 ret); 2585 break; 2586 case Opt_max_data_area_mb: 2587 ret = tcmu_set_max_blocks_param(udev, &args[0]); 2588 break; 2589 case Opt_data_pages_per_blk: 2590 ret = tcmu_set_data_pages_per_blk(udev, &args[0]); 2591 break; 2592 default: 2593 break; 2594 } 2595 2596 if (ret) 2597 break; 2598 } 2599 2600 kfree(orig); 2601 return (!ret) ? count : ret; 2602 } 2603 2604 static ssize_t tcmu_show_configfs_dev_params(struct se_device *dev, char *b) 2605 { 2606 struct tcmu_dev *udev = TCMU_DEV(dev); 2607 ssize_t bl = 0; 2608 2609 bl = sprintf(b + bl, "Config: %s ", 2610 udev->dev_config[0] ? udev->dev_config : "NULL"); 2611 bl += sprintf(b + bl, "Size: %llu ", udev->dev_size); 2612 bl += sprintf(b + bl, "MaxDataAreaMB: %u ", udev->data_area_mb); 2613 bl += sprintf(b + bl, "DataPagesPerBlk: %u\n", udev->data_pages_per_blk); 2614 2615 return bl; 2616 } 2617 2618 static sector_t tcmu_get_blocks(struct se_device *dev) 2619 { 2620 struct tcmu_dev *udev = TCMU_DEV(dev); 2621 2622 return div_u64(udev->dev_size - dev->dev_attrib.block_size, 2623 dev->dev_attrib.block_size); 2624 } 2625 2626 static sense_reason_t 2627 tcmu_parse_cdb(struct se_cmd *cmd) 2628 { 2629 return passthrough_parse_cdb(cmd, tcmu_queue_cmd); 2630 } 2631 2632 static ssize_t tcmu_cmd_time_out_show(struct config_item *item, char *page) 2633 { 2634 struct se_dev_attrib *da = container_of(to_config_group(item), 2635 struct se_dev_attrib, da_group); 2636 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2637 2638 return snprintf(page, PAGE_SIZE, "%lu\n", udev->cmd_time_out / MSEC_PER_SEC); 2639 } 2640 2641 static ssize_t tcmu_cmd_time_out_store(struct config_item *item, const char *page, 2642 size_t count) 2643 { 2644 struct se_dev_attrib *da = container_of(to_config_group(item), 2645 struct se_dev_attrib, da_group); 2646 struct tcmu_dev *udev = container_of(da->da_dev, 2647 struct tcmu_dev, se_dev); 2648 u32 val; 2649 int ret; 2650 2651 if (da->da_dev->export_count) { 2652 pr_err("Unable to set tcmu cmd_time_out while exports exist\n"); 2653 return -EINVAL; 2654 } 2655 2656 ret = kstrtou32(page, 0, &val); 2657 if (ret < 0) 2658 return ret; 2659 2660 udev->cmd_time_out = val * MSEC_PER_SEC; 2661 return count; 2662 } 2663 CONFIGFS_ATTR(tcmu_, cmd_time_out); 2664 2665 static ssize_t tcmu_qfull_time_out_show(struct config_item *item, char *page) 2666 { 2667 struct se_dev_attrib *da = container_of(to_config_group(item), 2668 struct se_dev_attrib, da_group); 2669 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2670 2671 return snprintf(page, PAGE_SIZE, "%ld\n", udev->qfull_time_out <= 0 ? 2672 udev->qfull_time_out : 2673 udev->qfull_time_out / MSEC_PER_SEC); 2674 } 2675 2676 static ssize_t tcmu_qfull_time_out_store(struct config_item *item, 2677 const char *page, size_t count) 2678 { 2679 struct se_dev_attrib *da = container_of(to_config_group(item), 2680 struct se_dev_attrib, da_group); 2681 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2682 s32 val; 2683 int ret; 2684 2685 ret = kstrtos32(page, 0, &val); 2686 if (ret < 0) 2687 return ret; 2688 2689 if (val >= 0) { 2690 udev->qfull_time_out = val * MSEC_PER_SEC; 2691 } else if (val == -1) { 2692 udev->qfull_time_out = val; 2693 } else { 2694 printk(KERN_ERR "Invalid qfull timeout value %d\n", val); 2695 return -EINVAL; 2696 } 2697 return count; 2698 } 2699 CONFIGFS_ATTR(tcmu_, qfull_time_out); 2700 2701 static ssize_t tcmu_max_data_area_mb_show(struct config_item *item, char *page) 2702 { 2703 struct se_dev_attrib *da = container_of(to_config_group(item), 2704 struct se_dev_attrib, da_group); 2705 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2706 2707 return snprintf(page, PAGE_SIZE, "%u\n", udev->data_area_mb); 2708 } 2709 CONFIGFS_ATTR_RO(tcmu_, max_data_area_mb); 2710 2711 static ssize_t tcmu_data_pages_per_blk_show(struct config_item *item, 2712 char *page) 2713 { 2714 struct se_dev_attrib *da = container_of(to_config_group(item), 2715 struct se_dev_attrib, da_group); 2716 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2717 2718 return snprintf(page, PAGE_SIZE, "%u\n", udev->data_pages_per_blk); 2719 } 2720 CONFIGFS_ATTR_RO(tcmu_, data_pages_per_blk); 2721 2722 static ssize_t tcmu_dev_config_show(struct config_item *item, char *page) 2723 { 2724 struct se_dev_attrib *da = container_of(to_config_group(item), 2725 struct se_dev_attrib, da_group); 2726 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2727 2728 return snprintf(page, PAGE_SIZE, "%s\n", udev->dev_config); 2729 } 2730 2731 static int tcmu_send_dev_config_event(struct tcmu_dev *udev, 2732 const char *reconfig_data) 2733 { 2734 struct sk_buff *skb = NULL; 2735 void *msg_header = NULL; 2736 int ret = 0; 2737 2738 ret = tcmu_netlink_event_init(udev, TCMU_CMD_RECONFIG_DEVICE, 2739 &skb, &msg_header); 2740 if (ret < 0) 2741 return ret; 2742 ret = nla_put_string(skb, TCMU_ATTR_DEV_CFG, reconfig_data); 2743 if (ret < 0) { 2744 nlmsg_free(skb); 2745 return ret; 2746 } 2747 return tcmu_netlink_event_send(udev, TCMU_CMD_RECONFIG_DEVICE, 2748 skb, msg_header); 2749 } 2750 2751 2752 static ssize_t tcmu_dev_config_store(struct config_item *item, const char *page, 2753 size_t count) 2754 { 2755 struct se_dev_attrib *da = container_of(to_config_group(item), 2756 struct se_dev_attrib, da_group); 2757 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2758 int ret, len; 2759 2760 len = strlen(page); 2761 if (!len || len > TCMU_CONFIG_LEN - 1) 2762 return -EINVAL; 2763 2764 /* Check if device has been configured before */ 2765 if (target_dev_configured(&udev->se_dev)) { 2766 ret = tcmu_send_dev_config_event(udev, page); 2767 if (ret) { 2768 pr_err("Unable to reconfigure device\n"); 2769 return ret; 2770 } 2771 strlcpy(udev->dev_config, page, TCMU_CONFIG_LEN); 2772 2773 ret = tcmu_update_uio_info(udev); 2774 if (ret) 2775 return ret; 2776 return count; 2777 } 2778 strlcpy(udev->dev_config, page, TCMU_CONFIG_LEN); 2779 2780 return count; 2781 } 2782 CONFIGFS_ATTR(tcmu_, dev_config); 2783 2784 static ssize_t tcmu_dev_size_show(struct config_item *item, char *page) 2785 { 2786 struct se_dev_attrib *da = container_of(to_config_group(item), 2787 struct se_dev_attrib, da_group); 2788 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2789 2790 return snprintf(page, PAGE_SIZE, "%llu\n", udev->dev_size); 2791 } 2792 2793 static int tcmu_send_dev_size_event(struct tcmu_dev *udev, u64 size) 2794 { 2795 struct sk_buff *skb = NULL; 2796 void *msg_header = NULL; 2797 int ret = 0; 2798 2799 ret = tcmu_netlink_event_init(udev, TCMU_CMD_RECONFIG_DEVICE, 2800 &skb, &msg_header); 2801 if (ret < 0) 2802 return ret; 2803 ret = nla_put_u64_64bit(skb, TCMU_ATTR_DEV_SIZE, 2804 size, TCMU_ATTR_PAD); 2805 if (ret < 0) { 2806 nlmsg_free(skb); 2807 return ret; 2808 } 2809 return tcmu_netlink_event_send(udev, TCMU_CMD_RECONFIG_DEVICE, 2810 skb, msg_header); 2811 } 2812 2813 static ssize_t tcmu_dev_size_store(struct config_item *item, const char *page, 2814 size_t count) 2815 { 2816 struct se_dev_attrib *da = container_of(to_config_group(item), 2817 struct se_dev_attrib, da_group); 2818 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2819 u64 val; 2820 int ret; 2821 2822 ret = kstrtou64(page, 0, &val); 2823 if (ret < 0) 2824 return ret; 2825 2826 /* Check if device has been configured before */ 2827 if (target_dev_configured(&udev->se_dev)) { 2828 ret = tcmu_send_dev_size_event(udev, val); 2829 if (ret) { 2830 pr_err("Unable to reconfigure device\n"); 2831 return ret; 2832 } 2833 } 2834 udev->dev_size = val; 2835 return count; 2836 } 2837 CONFIGFS_ATTR(tcmu_, dev_size); 2838 2839 static ssize_t tcmu_nl_reply_supported_show(struct config_item *item, 2840 char *page) 2841 { 2842 struct se_dev_attrib *da = container_of(to_config_group(item), 2843 struct se_dev_attrib, da_group); 2844 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2845 2846 return snprintf(page, PAGE_SIZE, "%d\n", udev->nl_reply_supported); 2847 } 2848 2849 static ssize_t tcmu_nl_reply_supported_store(struct config_item *item, 2850 const char *page, size_t count) 2851 { 2852 struct se_dev_attrib *da = container_of(to_config_group(item), 2853 struct se_dev_attrib, da_group); 2854 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2855 s8 val; 2856 int ret; 2857 2858 ret = kstrtos8(page, 0, &val); 2859 if (ret < 0) 2860 return ret; 2861 2862 udev->nl_reply_supported = val; 2863 return count; 2864 } 2865 CONFIGFS_ATTR(tcmu_, nl_reply_supported); 2866 2867 static ssize_t tcmu_emulate_write_cache_show(struct config_item *item, 2868 char *page) 2869 { 2870 struct se_dev_attrib *da = container_of(to_config_group(item), 2871 struct se_dev_attrib, da_group); 2872 2873 return snprintf(page, PAGE_SIZE, "%i\n", da->emulate_write_cache); 2874 } 2875 2876 static int tcmu_send_emulate_write_cache(struct tcmu_dev *udev, u8 val) 2877 { 2878 struct sk_buff *skb = NULL; 2879 void *msg_header = NULL; 2880 int ret = 0; 2881 2882 ret = tcmu_netlink_event_init(udev, TCMU_CMD_RECONFIG_DEVICE, 2883 &skb, &msg_header); 2884 if (ret < 0) 2885 return ret; 2886 ret = nla_put_u8(skb, TCMU_ATTR_WRITECACHE, val); 2887 if (ret < 0) { 2888 nlmsg_free(skb); 2889 return ret; 2890 } 2891 return tcmu_netlink_event_send(udev, TCMU_CMD_RECONFIG_DEVICE, 2892 skb, msg_header); 2893 } 2894 2895 static ssize_t tcmu_emulate_write_cache_store(struct config_item *item, 2896 const char *page, size_t count) 2897 { 2898 struct se_dev_attrib *da = container_of(to_config_group(item), 2899 struct se_dev_attrib, da_group); 2900 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2901 u8 val; 2902 int ret; 2903 2904 ret = kstrtou8(page, 0, &val); 2905 if (ret < 0) 2906 return ret; 2907 2908 /* Check if device has been configured before */ 2909 if (target_dev_configured(&udev->se_dev)) { 2910 ret = tcmu_send_emulate_write_cache(udev, val); 2911 if (ret) { 2912 pr_err("Unable to reconfigure device\n"); 2913 return ret; 2914 } 2915 } 2916 2917 da->emulate_write_cache = val; 2918 return count; 2919 } 2920 CONFIGFS_ATTR(tcmu_, emulate_write_cache); 2921 2922 static ssize_t tcmu_tmr_notification_show(struct config_item *item, char *page) 2923 { 2924 struct se_dev_attrib *da = container_of(to_config_group(item), 2925 struct se_dev_attrib, da_group); 2926 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2927 2928 return snprintf(page, PAGE_SIZE, "%i\n", 2929 test_bit(TCMU_DEV_BIT_TMR_NOTIFY, &udev->flags)); 2930 } 2931 2932 static ssize_t tcmu_tmr_notification_store(struct config_item *item, 2933 const char *page, size_t count) 2934 { 2935 struct se_dev_attrib *da = container_of(to_config_group(item), 2936 struct se_dev_attrib, da_group); 2937 struct tcmu_dev *udev = TCMU_DEV(da->da_dev); 2938 u8 val; 2939 int ret; 2940 2941 ret = kstrtou8(page, 0, &val); 2942 if (ret < 0) 2943 return ret; 2944 if (val > 1) 2945 return -EINVAL; 2946 2947 if (val) 2948 set_bit(TCMU_DEV_BIT_TMR_NOTIFY, &udev->flags); 2949 else 2950 clear_bit(TCMU_DEV_BIT_TMR_NOTIFY, &udev->flags); 2951 return count; 2952 } 2953 CONFIGFS_ATTR(tcmu_, tmr_notification); 2954 2955 static ssize_t tcmu_block_dev_show(struct config_item *item, char *page) 2956 { 2957 struct se_device *se_dev = container_of(to_config_group(item), 2958 struct se_device, 2959 dev_action_group); 2960 struct tcmu_dev *udev = TCMU_DEV(se_dev); 2961 2962 if (test_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags)) 2963 return snprintf(page, PAGE_SIZE, "%s\n", "blocked"); 2964 else 2965 return snprintf(page, PAGE_SIZE, "%s\n", "unblocked"); 2966 } 2967 2968 static ssize_t tcmu_block_dev_store(struct config_item *item, const char *page, 2969 size_t count) 2970 { 2971 struct se_device *se_dev = container_of(to_config_group(item), 2972 struct se_device, 2973 dev_action_group); 2974 struct tcmu_dev *udev = TCMU_DEV(se_dev); 2975 u8 val; 2976 int ret; 2977 2978 if (!target_dev_configured(&udev->se_dev)) { 2979 pr_err("Device is not configured.\n"); 2980 return -EINVAL; 2981 } 2982 2983 ret = kstrtou8(page, 0, &val); 2984 if (ret < 0) 2985 return ret; 2986 2987 if (val > 1) { 2988 pr_err("Invalid block value %d\n", val); 2989 return -EINVAL; 2990 } 2991 2992 if (!val) 2993 tcmu_unblock_dev(udev); 2994 else 2995 tcmu_block_dev(udev); 2996 return count; 2997 } 2998 CONFIGFS_ATTR(tcmu_, block_dev); 2999 3000 static ssize_t tcmu_reset_ring_store(struct config_item *item, const char *page, 3001 size_t count) 3002 { 3003 struct se_device *se_dev = container_of(to_config_group(item), 3004 struct se_device, 3005 dev_action_group); 3006 struct tcmu_dev *udev = TCMU_DEV(se_dev); 3007 u8 val; 3008 int ret; 3009 3010 if (!target_dev_configured(&udev->se_dev)) { 3011 pr_err("Device is not configured.\n"); 3012 return -EINVAL; 3013 } 3014 3015 ret = kstrtou8(page, 0, &val); 3016 if (ret < 0) 3017 return ret; 3018 3019 if (val != 1 && val != 2) { 3020 pr_err("Invalid reset ring value %d\n", val); 3021 return -EINVAL; 3022 } 3023 3024 tcmu_reset_ring(udev, val); 3025 return count; 3026 } 3027 CONFIGFS_ATTR_WO(tcmu_, reset_ring); 3028 3029 static ssize_t tcmu_free_kept_buf_store(struct config_item *item, const char *page, 3030 size_t count) 3031 { 3032 struct se_device *se_dev = container_of(to_config_group(item), 3033 struct se_device, 3034 dev_action_group); 3035 struct tcmu_dev *udev = TCMU_DEV(se_dev); 3036 struct tcmu_cmd *cmd; 3037 u16 cmd_id; 3038 int ret; 3039 3040 if (!target_dev_configured(&udev->se_dev)) { 3041 pr_err("Device is not configured.\n"); 3042 return -EINVAL; 3043 } 3044 3045 ret = kstrtou16(page, 0, &cmd_id); 3046 if (ret < 0) 3047 return ret; 3048 3049 mutex_lock(&udev->cmdr_lock); 3050 3051 { 3052 XA_STATE(xas, &udev->commands, cmd_id); 3053 3054 xas_lock(&xas); 3055 cmd = xas_load(&xas); 3056 if (!cmd) { 3057 pr_err("free_kept_buf: cmd_id %d not found\n", cmd_id); 3058 count = -EINVAL; 3059 xas_unlock(&xas); 3060 goto out_unlock; 3061 } 3062 if (!test_bit(TCMU_CMD_BIT_KEEP_BUF, &cmd->flags)) { 3063 pr_err("free_kept_buf: cmd_id %d was not completed with KEEP_BUF\n", 3064 cmd_id); 3065 count = -EINVAL; 3066 xas_unlock(&xas); 3067 goto out_unlock; 3068 } 3069 xas_store(&xas, NULL); 3070 xas_unlock(&xas); 3071 } 3072 3073 tcmu_cmd_free_data(cmd, cmd->dbi_cnt); 3074 tcmu_free_cmd(cmd); 3075 /* 3076 * We only freed data space, not ring space. Therefore we dont call 3077 * run_tmr_queue, but call run_qfull_queue if tmr_list is empty. 3078 */ 3079 if (list_empty(&udev->tmr_queue)) 3080 run_qfull_queue(udev, false); 3081 3082 out_unlock: 3083 mutex_unlock(&udev->cmdr_lock); 3084 return count; 3085 } 3086 CONFIGFS_ATTR_WO(tcmu_, free_kept_buf); 3087 3088 static struct configfs_attribute *tcmu_attrib_attrs[] = { 3089 &tcmu_attr_cmd_time_out, 3090 &tcmu_attr_qfull_time_out, 3091 &tcmu_attr_max_data_area_mb, 3092 &tcmu_attr_data_pages_per_blk, 3093 &tcmu_attr_dev_config, 3094 &tcmu_attr_dev_size, 3095 &tcmu_attr_emulate_write_cache, 3096 &tcmu_attr_tmr_notification, 3097 &tcmu_attr_nl_reply_supported, 3098 NULL, 3099 }; 3100 3101 static struct configfs_attribute **tcmu_attrs; 3102 3103 static struct configfs_attribute *tcmu_action_attrs[] = { 3104 &tcmu_attr_block_dev, 3105 &tcmu_attr_reset_ring, 3106 &tcmu_attr_free_kept_buf, 3107 NULL, 3108 }; 3109 3110 static struct target_backend_ops tcmu_ops = { 3111 .name = "user", 3112 .owner = THIS_MODULE, 3113 .transport_flags_default = TRANSPORT_FLAG_PASSTHROUGH, 3114 .transport_flags_changeable = TRANSPORT_FLAG_PASSTHROUGH_PGR | 3115 TRANSPORT_FLAG_PASSTHROUGH_ALUA, 3116 .attach_hba = tcmu_attach_hba, 3117 .detach_hba = tcmu_detach_hba, 3118 .alloc_device = tcmu_alloc_device, 3119 .configure_device = tcmu_configure_device, 3120 .destroy_device = tcmu_destroy_device, 3121 .free_device = tcmu_free_device, 3122 .unplug_device = tcmu_unplug_device, 3123 .plug_device = tcmu_plug_device, 3124 .parse_cdb = tcmu_parse_cdb, 3125 .tmr_notify = tcmu_tmr_notify, 3126 .set_configfs_dev_params = tcmu_set_configfs_dev_params, 3127 .show_configfs_dev_params = tcmu_show_configfs_dev_params, 3128 .get_device_type = sbc_get_device_type, 3129 .get_blocks = tcmu_get_blocks, 3130 .tb_dev_action_attrs = tcmu_action_attrs, 3131 }; 3132 3133 static void find_free_blocks(void) 3134 { 3135 struct tcmu_dev *udev; 3136 loff_t off; 3137 u32 pages_freed, total_pages_freed = 0; 3138 u32 start, end, block, total_blocks_freed = 0; 3139 3140 if (atomic_read(&global_page_count) <= tcmu_global_max_pages) 3141 return; 3142 3143 mutex_lock(&root_udev_mutex); 3144 list_for_each_entry(udev, &root_udev, node) { 3145 mutex_lock(&udev->cmdr_lock); 3146 3147 if (!target_dev_configured(&udev->se_dev)) { 3148 mutex_unlock(&udev->cmdr_lock); 3149 continue; 3150 } 3151 3152 /* Try to complete the finished commands first */ 3153 if (tcmu_handle_completions(udev)) 3154 run_qfull_queue(udev, false); 3155 3156 /* Skip the udevs in idle */ 3157 if (!udev->dbi_thresh) { 3158 mutex_unlock(&udev->cmdr_lock); 3159 continue; 3160 } 3161 3162 end = udev->dbi_max + 1; 3163 block = find_last_bit(udev->data_bitmap, end); 3164 if (block == udev->dbi_max) { 3165 /* 3166 * The last bit is dbi_max, so it is not possible 3167 * reclaim any blocks. 3168 */ 3169 mutex_unlock(&udev->cmdr_lock); 3170 continue; 3171 } else if (block == end) { 3172 /* The current udev will goto idle state */ 3173 udev->dbi_thresh = start = 0; 3174 udev->dbi_max = 0; 3175 } else { 3176 udev->dbi_thresh = start = block + 1; 3177 udev->dbi_max = block; 3178 } 3179 3180 /* 3181 * Release the block pages. 3182 * 3183 * Also note that since tcmu_vma_fault() gets an extra page 3184 * refcount, tcmu_blocks_release() won't free pages if pages 3185 * are mapped. This means it is safe to call 3186 * tcmu_blocks_release() before unmap_mapping_range() which 3187 * drops the refcount of any pages it unmaps and thus releases 3188 * them. 3189 */ 3190 pages_freed = tcmu_blocks_release(udev, start, end - 1); 3191 3192 /* Here will truncate the data area from off */ 3193 off = udev->data_off + (loff_t)start * udev->data_blk_size; 3194 unmap_mapping_range(udev->inode->i_mapping, off, 0, 1); 3195 3196 mutex_unlock(&udev->cmdr_lock); 3197 3198 total_pages_freed += pages_freed; 3199 total_blocks_freed += end - start; 3200 pr_debug("Freed %u pages (total %u) from %u blocks (total %u) from %s.\n", 3201 pages_freed, total_pages_freed, end - start, 3202 total_blocks_freed, udev->name); 3203 } 3204 mutex_unlock(&root_udev_mutex); 3205 3206 if (atomic_read(&global_page_count) > tcmu_global_max_pages) 3207 schedule_delayed_work(&tcmu_unmap_work, msecs_to_jiffies(5000)); 3208 } 3209 3210 static void check_timedout_devices(void) 3211 { 3212 struct tcmu_dev *udev, *tmp_dev; 3213 struct tcmu_cmd *cmd, *tmp_cmd; 3214 LIST_HEAD(devs); 3215 3216 spin_lock_bh(&timed_out_udevs_lock); 3217 list_splice_init(&timed_out_udevs, &devs); 3218 3219 list_for_each_entry_safe(udev, tmp_dev, &devs, timedout_entry) { 3220 list_del_init(&udev->timedout_entry); 3221 spin_unlock_bh(&timed_out_udevs_lock); 3222 3223 mutex_lock(&udev->cmdr_lock); 3224 3225 /* 3226 * If cmd_time_out is disabled but qfull is set deadline 3227 * will only reflect the qfull timeout. Ignore it. 3228 */ 3229 if (udev->cmd_time_out) { 3230 list_for_each_entry_safe(cmd, tmp_cmd, 3231 &udev->inflight_queue, 3232 queue_entry) { 3233 tcmu_check_expired_ring_cmd(cmd); 3234 } 3235 tcmu_set_next_deadline(&udev->inflight_queue, 3236 &udev->cmd_timer); 3237 } 3238 list_for_each_entry_safe(cmd, tmp_cmd, &udev->qfull_queue, 3239 queue_entry) { 3240 tcmu_check_expired_queue_cmd(cmd); 3241 } 3242 tcmu_set_next_deadline(&udev->qfull_queue, &udev->qfull_timer); 3243 3244 mutex_unlock(&udev->cmdr_lock); 3245 3246 spin_lock_bh(&timed_out_udevs_lock); 3247 } 3248 3249 spin_unlock_bh(&timed_out_udevs_lock); 3250 } 3251 3252 static void tcmu_unmap_work_fn(struct work_struct *work) 3253 { 3254 check_timedout_devices(); 3255 find_free_blocks(); 3256 } 3257 3258 static int __init tcmu_module_init(void) 3259 { 3260 int ret, i, k, len = 0; 3261 3262 BUILD_BUG_ON((sizeof(struct tcmu_cmd_entry) % TCMU_OP_ALIGN_SIZE) != 0); 3263 3264 INIT_DELAYED_WORK(&tcmu_unmap_work, tcmu_unmap_work_fn); 3265 3266 tcmu_cmd_cache = kmem_cache_create("tcmu_cmd_cache", 3267 sizeof(struct tcmu_cmd), 3268 __alignof__(struct tcmu_cmd), 3269 0, NULL); 3270 if (!tcmu_cmd_cache) 3271 return -ENOMEM; 3272 3273 tcmu_root_device = root_device_register("tcm_user"); 3274 if (IS_ERR(tcmu_root_device)) { 3275 ret = PTR_ERR(tcmu_root_device); 3276 goto out_free_cache; 3277 } 3278 3279 ret = genl_register_family(&tcmu_genl_family); 3280 if (ret < 0) { 3281 goto out_unreg_device; 3282 } 3283 3284 for (i = 0; passthrough_attrib_attrs[i] != NULL; i++) 3285 len += sizeof(struct configfs_attribute *); 3286 for (i = 0; passthrough_pr_attrib_attrs[i] != NULL; i++) 3287 len += sizeof(struct configfs_attribute *); 3288 for (i = 0; tcmu_attrib_attrs[i] != NULL; i++) 3289 len += sizeof(struct configfs_attribute *); 3290 len += sizeof(struct configfs_attribute *); 3291 3292 tcmu_attrs = kzalloc(len, GFP_KERNEL); 3293 if (!tcmu_attrs) { 3294 ret = -ENOMEM; 3295 goto out_unreg_genl; 3296 } 3297 3298 for (i = 0; passthrough_attrib_attrs[i] != NULL; i++) 3299 tcmu_attrs[i] = passthrough_attrib_attrs[i]; 3300 for (k = 0; passthrough_pr_attrib_attrs[k] != NULL; k++) 3301 tcmu_attrs[i++] = passthrough_pr_attrib_attrs[k]; 3302 for (k = 0; tcmu_attrib_attrs[k] != NULL; k++) 3303 tcmu_attrs[i++] = tcmu_attrib_attrs[k]; 3304 tcmu_ops.tb_dev_attrib_attrs = tcmu_attrs; 3305 3306 ret = transport_backend_register(&tcmu_ops); 3307 if (ret) 3308 goto out_attrs; 3309 3310 return 0; 3311 3312 out_attrs: 3313 kfree(tcmu_attrs); 3314 out_unreg_genl: 3315 genl_unregister_family(&tcmu_genl_family); 3316 out_unreg_device: 3317 root_device_unregister(tcmu_root_device); 3318 out_free_cache: 3319 kmem_cache_destroy(tcmu_cmd_cache); 3320 3321 return ret; 3322 } 3323 3324 static void __exit tcmu_module_exit(void) 3325 { 3326 cancel_delayed_work_sync(&tcmu_unmap_work); 3327 target_backend_unregister(&tcmu_ops); 3328 kfree(tcmu_attrs); 3329 genl_unregister_family(&tcmu_genl_family); 3330 root_device_unregister(tcmu_root_device); 3331 kmem_cache_destroy(tcmu_cmd_cache); 3332 } 3333 3334 MODULE_DESCRIPTION("TCM USER subsystem plugin"); 3335 MODULE_AUTHOR("Shaohua Li <shli@kernel.org>"); 3336 MODULE_AUTHOR("Andy Grover <agrover@redhat.com>"); 3337 MODULE_LICENSE("GPL"); 3338 3339 module_init(tcmu_module_init); 3340 module_exit(tcmu_module_exit); 3341