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9#include <linux/spinlock.h>
10#include <linux/module.h>
11#include <linux/idr.h>
12#include <linux/kernel.h>
13#include <linux/timer.h>
14#include <linux/parser.h>
15#include <linux/vmalloc.h>
16#include <linux/uio_driver.h>
17#include <linux/radix-tree.h>
18#include <linux/stringify.h>
19#include <linux/bitops.h>
20#include <linux/highmem.h>
21#include <linux/configfs.h>
22#include <linux/mutex.h>
23#include <linux/workqueue.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
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61
62#define TCMU_TIME_OUT (30 * MSEC_PER_SEC)
63
64
65#define CMDR_SIZE (8 * 1024 * 1024)
66
67
68
69
70
71#define DATA_BLOCK_SIZE PAGE_SIZE
72#define DATA_BLOCK_SHIFT PAGE_SHIFT
73#define DATA_BLOCK_BITS_DEF (256 * 1024)
74
75#define TCMU_MBS_TO_BLOCKS(_mbs) (_mbs << (20 - DATA_BLOCK_SHIFT))
76#define TCMU_BLOCKS_TO_MBS(_blocks) (_blocks >> (20 - DATA_BLOCK_SHIFT))
77
78
79
80
81
82#define TCMU_GLOBAL_MAX_BLOCKS_DEF (512 * 1024)
83
84static u8 tcmu_kern_cmd_reply_supported;
85static u8 tcmu_netlink_blocked;
86
87static struct device *tcmu_root_device;
88
89struct tcmu_hba {
90 u32 host_id;
91};
92
93#define TCMU_CONFIG_LEN 256
94
95static DEFINE_MUTEX(tcmu_nl_cmd_mutex);
96static LIST_HEAD(tcmu_nl_cmd_list);
97
98struct tcmu_dev;
99
100struct tcmu_nl_cmd {
101
102 struct completion complete;
103 struct list_head nl_list;
104 struct tcmu_dev *udev;
105 int cmd;
106 int status;
107};
108
109struct tcmu_dev {
110 struct list_head node;
111 struct kref kref;
112
113 struct se_device se_dev;
114
115 char *name;
116 struct se_hba *hba;
117
118#define TCMU_DEV_BIT_OPEN 0
119#define TCMU_DEV_BIT_BROKEN 1
120#define TCMU_DEV_BIT_BLOCKED 2
121 unsigned long flags;
122
123 struct uio_info uio_info;
124
125 struct inode *inode;
126
127 struct tcmu_mailbox *mb_addr;
128 uint64_t dev_size;
129 u32 cmdr_size;
130 u32 cmdr_last_cleaned;
131
132
133 size_t data_off;
134 size_t data_size;
135 uint32_t max_blocks;
136 size_t ring_size;
137
138 struct mutex cmdr_lock;
139 struct list_head qfull_queue;
140
141 uint32_t dbi_max;
142 uint32_t dbi_thresh;
143 unsigned long *data_bitmap;
144 struct radix_tree_root data_blocks;
145
146 struct idr commands;
147
148 struct timer_list cmd_timer;
149 unsigned int cmd_time_out;
150 struct list_head inflight_queue;
151
152 struct timer_list qfull_timer;
153 int qfull_time_out;
154
155 struct list_head timedout_entry;
156
157 struct tcmu_nl_cmd curr_nl_cmd;
158
159 char dev_config[TCMU_CONFIG_LEN];
160
161 int nl_reply_supported;
162};
163
164#define TCMU_DEV(_se_dev) container_of(_se_dev, struct tcmu_dev, se_dev)
165
166#define CMDR_OFF sizeof(struct tcmu_mailbox)
167
168struct tcmu_cmd {
169 struct se_cmd *se_cmd;
170 struct tcmu_dev *tcmu_dev;
171 struct list_head queue_entry;
172
173 uint16_t cmd_id;
174
175
176
177 uint32_t dbi_cnt;
178 uint32_t dbi_cur;
179 uint32_t *dbi;
180
181 unsigned long deadline;
182
183#define TCMU_CMD_BIT_EXPIRED 0
184#define TCMU_CMD_BIT_INFLIGHT 1
185 unsigned long flags;
186};
187
188
189
190
191
192
193
194
195
196
197static DEFINE_MUTEX(root_udev_mutex);
198static LIST_HEAD(root_udev);
199
200static DEFINE_SPINLOCK(timed_out_udevs_lock);
201static LIST_HEAD(timed_out_udevs);
202
203static struct kmem_cache *tcmu_cmd_cache;
204
205static atomic_t global_db_count = ATOMIC_INIT(0);
206static struct delayed_work tcmu_unmap_work;
207static int tcmu_global_max_blocks = TCMU_GLOBAL_MAX_BLOCKS_DEF;
208
209static int tcmu_set_global_max_data_area(const char *str,
210 const struct kernel_param *kp)
211{
212 int ret, max_area_mb;
213
214 ret = kstrtoint(str, 10, &max_area_mb);
215 if (ret)
216 return -EINVAL;
217
218 if (max_area_mb <= 0) {
219 pr_err("global_max_data_area must be larger than 0.\n");
220 return -EINVAL;
221 }
222
223 tcmu_global_max_blocks = TCMU_MBS_TO_BLOCKS(max_area_mb);
224 if (atomic_read(&global_db_count) > tcmu_global_max_blocks)
225 schedule_delayed_work(&tcmu_unmap_work, 0);
226 else
227 cancel_delayed_work_sync(&tcmu_unmap_work);
228
229 return 0;
230}
231
232static int tcmu_get_global_max_data_area(char *buffer,
233 const struct kernel_param *kp)
234{
235 return sprintf(buffer, "%d", TCMU_BLOCKS_TO_MBS(tcmu_global_max_blocks));
236}
237
238static const struct kernel_param_ops tcmu_global_max_data_area_op = {
239 .set = tcmu_set_global_max_data_area,
240 .get = tcmu_get_global_max_data_area,
241};
242
243module_param_cb(global_max_data_area_mb, &tcmu_global_max_data_area_op, NULL,
244 S_IWUSR | S_IRUGO);
245MODULE_PARM_DESC(global_max_data_area_mb,
246 "Max MBs allowed to be allocated to all the tcmu device's "
247 "data areas.");
248
249static int tcmu_get_block_netlink(char *buffer,
250 const struct kernel_param *kp)
251{
252 return sprintf(buffer, "%s\n", tcmu_netlink_blocked ?
253 "blocked" : "unblocked");
254}
255
256static int tcmu_set_block_netlink(const char *str,
257 const struct kernel_param *kp)
258{
259 int ret;
260 u8 val;
261
262 ret = kstrtou8(str, 0, &val);
263 if (ret < 0)
264 return ret;
265
266 if (val > 1) {
267 pr_err("Invalid block netlink value %u\n", val);
268 return -EINVAL;
269 }
270
271 tcmu_netlink_blocked = val;
272 return 0;
273}
274
275static const struct kernel_param_ops tcmu_block_netlink_op = {
276 .set = tcmu_set_block_netlink,
277 .get = tcmu_get_block_netlink,
278};
279
280module_param_cb(block_netlink, &tcmu_block_netlink_op, NULL, S_IWUSR | S_IRUGO);
281MODULE_PARM_DESC(block_netlink, "Block new netlink commands.");
282
283static int tcmu_fail_netlink_cmd(struct tcmu_nl_cmd *nl_cmd)
284{
285 struct tcmu_dev *udev = nl_cmd->udev;
286
287 if (!tcmu_netlink_blocked) {
288 pr_err("Could not reset device's netlink interface. Netlink is not blocked.\n");
289 return -EBUSY;
290 }
291
292 if (nl_cmd->cmd != TCMU_CMD_UNSPEC) {
293 pr_debug("Aborting nl cmd %d on %s\n", nl_cmd->cmd, udev->name);
294 nl_cmd->status = -EINTR;
295 list_del(&nl_cmd->nl_list);
296 complete(&nl_cmd->complete);
297 }
298 return 0;
299}
300
301static int tcmu_set_reset_netlink(const char *str,
302 const struct kernel_param *kp)
303{
304 struct tcmu_nl_cmd *nl_cmd, *tmp_cmd;
305 int ret;
306 u8 val;
307
308 ret = kstrtou8(str, 0, &val);
309 if (ret < 0)
310 return ret;
311
312 if (val != 1) {
313 pr_err("Invalid reset netlink value %u\n", val);
314 return -EINVAL;
315 }
316
317 mutex_lock(&tcmu_nl_cmd_mutex);
318 list_for_each_entry_safe(nl_cmd, tmp_cmd, &tcmu_nl_cmd_list, nl_list) {
319 ret = tcmu_fail_netlink_cmd(nl_cmd);
320 if (ret)
321 break;
322 }
323 mutex_unlock(&tcmu_nl_cmd_mutex);
324
325 return ret;
326}
327
328static const struct kernel_param_ops tcmu_reset_netlink_op = {
329 .set = tcmu_set_reset_netlink,
330};
331
332module_param_cb(reset_netlink, &tcmu_reset_netlink_op, NULL, S_IWUSR);
333MODULE_PARM_DESC(reset_netlink, "Reset netlink commands.");
334
335
336enum tcmu_multicast_groups {
337 TCMU_MCGRP_CONFIG,
338};
339
340static const struct genl_multicast_group tcmu_mcgrps[] = {
341 [TCMU_MCGRP_CONFIG] = { .name = "config", },
342};
343
344static struct nla_policy tcmu_attr_policy[TCMU_ATTR_MAX+1] = {
345 [TCMU_ATTR_DEVICE] = { .type = NLA_STRING },
346 [TCMU_ATTR_MINOR] = { .type = NLA_U32 },
347 [TCMU_ATTR_CMD_STATUS] = { .type = NLA_S32 },
348 [TCMU_ATTR_DEVICE_ID] = { .type = NLA_U32 },
349 [TCMU_ATTR_SUPP_KERN_CMD_REPLY] = { .type = NLA_U8 },
350};
351
352static int tcmu_genl_cmd_done(struct genl_info *info, int completed_cmd)
353{
354 struct tcmu_dev *udev = NULL;
355 struct tcmu_nl_cmd *nl_cmd;
356 int dev_id, rc, ret = 0;
357
358 if (!info->attrs[TCMU_ATTR_CMD_STATUS] ||
359 !info->attrs[TCMU_ATTR_DEVICE_ID]) {
360 printk(KERN_ERR "TCMU_ATTR_CMD_STATUS or TCMU_ATTR_DEVICE_ID not set, doing nothing\n");
361 return -EINVAL;
362 }
363
364 dev_id = nla_get_u32(info->attrs[TCMU_ATTR_DEVICE_ID]);
365 rc = nla_get_s32(info->attrs[TCMU_ATTR_CMD_STATUS]);
366
367 mutex_lock(&tcmu_nl_cmd_mutex);
368 list_for_each_entry(nl_cmd, &tcmu_nl_cmd_list, nl_list) {
369 if (nl_cmd->udev->se_dev.dev_index == dev_id) {
370 udev = nl_cmd->udev;
371 break;
372 }
373 }
374
375 if (!udev) {
376 pr_err("tcmu nl cmd %u/%d completion could not find device with dev id %u.\n",
377 completed_cmd, rc, dev_id);
378 ret = -ENODEV;
379 goto unlock;
380 }
381 list_del(&nl_cmd->nl_list);
382
383 pr_debug("%s genl cmd done got id %d curr %d done %d rc %d stat %d\n",
384 udev->name, dev_id, nl_cmd->cmd, completed_cmd, rc,
385 nl_cmd->status);
386
387 if (nl_cmd->cmd != completed_cmd) {
388 pr_err("Mismatched commands on %s (Expecting reply for %d. Current %d).\n",
389 udev->name, completed_cmd, nl_cmd->cmd);
390 ret = -EINVAL;
391 goto unlock;
392 }
393
394 nl_cmd->status = rc;
395 complete(&nl_cmd->complete);
396unlock:
397 mutex_unlock(&tcmu_nl_cmd_mutex);
398 return ret;
399}
400
401static int tcmu_genl_rm_dev_done(struct sk_buff *skb, struct genl_info *info)
402{
403 return tcmu_genl_cmd_done(info, TCMU_CMD_REMOVED_DEVICE);
404}
405
406static int tcmu_genl_add_dev_done(struct sk_buff *skb, struct genl_info *info)
407{
408 return tcmu_genl_cmd_done(info, TCMU_CMD_ADDED_DEVICE);
409}
410
411static int tcmu_genl_reconfig_dev_done(struct sk_buff *skb,
412 struct genl_info *info)
413{
414 return tcmu_genl_cmd_done(info, TCMU_CMD_RECONFIG_DEVICE);
415}
416
417static int tcmu_genl_set_features(struct sk_buff *skb, struct genl_info *info)
418{
419 if (info->attrs[TCMU_ATTR_SUPP_KERN_CMD_REPLY]) {
420 tcmu_kern_cmd_reply_supported =
421 nla_get_u8(info->attrs[TCMU_ATTR_SUPP_KERN_CMD_REPLY]);
422 printk(KERN_INFO "tcmu daemon: command reply support %u.\n",
423 tcmu_kern_cmd_reply_supported);
424 }
425
426 return 0;
427}
428
429static const struct genl_ops tcmu_genl_ops[] = {
430 {
431 .cmd = TCMU_CMD_SET_FEATURES,
432 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
433 .flags = GENL_ADMIN_PERM,
434 .doit = tcmu_genl_set_features,
435 },
436 {
437 .cmd = TCMU_CMD_ADDED_DEVICE_DONE,
438 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
439 .flags = GENL_ADMIN_PERM,
440 .doit = tcmu_genl_add_dev_done,
441 },
442 {
443 .cmd = TCMU_CMD_REMOVED_DEVICE_DONE,
444 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
445 .flags = GENL_ADMIN_PERM,
446 .doit = tcmu_genl_rm_dev_done,
447 },
448 {
449 .cmd = TCMU_CMD_RECONFIG_DEVICE_DONE,
450 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
451 .flags = GENL_ADMIN_PERM,
452 .doit = tcmu_genl_reconfig_dev_done,
453 },
454};
455
456
457static struct genl_family tcmu_genl_family __ro_after_init = {
458 .module = THIS_MODULE,
459 .hdrsize = 0,
460 .name = "TCM-USER",
461 .version = 2,
462 .maxattr = TCMU_ATTR_MAX,
463 .policy = tcmu_attr_policy,
464 .mcgrps = tcmu_mcgrps,
465 .n_mcgrps = ARRAY_SIZE(tcmu_mcgrps),
466 .netnsok = true,
467 .ops = tcmu_genl_ops,
468 .n_ops = ARRAY_SIZE(tcmu_genl_ops),
469};
470
471#define tcmu_cmd_set_dbi_cur(cmd, index) ((cmd)->dbi_cur = (index))
472#define tcmu_cmd_reset_dbi_cur(cmd) tcmu_cmd_set_dbi_cur(cmd, 0)
473#define tcmu_cmd_set_dbi(cmd, index) ((cmd)->dbi[(cmd)->dbi_cur++] = (index))
474#define tcmu_cmd_get_dbi(cmd) ((cmd)->dbi[(cmd)->dbi_cur++])
475
476static void tcmu_cmd_free_data(struct tcmu_cmd *tcmu_cmd, uint32_t len)
477{
478 struct tcmu_dev *udev = tcmu_cmd->tcmu_dev;
479 uint32_t i;
480
481 for (i = 0; i < len; i++)
482 clear_bit(tcmu_cmd->dbi[i], udev->data_bitmap);
483}
484
485static inline bool tcmu_get_empty_block(struct tcmu_dev *udev,
486 struct tcmu_cmd *tcmu_cmd)
487{
488 struct page *page;
489 int ret, dbi;
490
491 dbi = find_first_zero_bit(udev->data_bitmap, udev->dbi_thresh);
492 if (dbi == udev->dbi_thresh)
493 return false;
494
495 page = radix_tree_lookup(&udev->data_blocks, dbi);
496 if (!page) {
497 if (atomic_add_return(1, &global_db_count) >
498 tcmu_global_max_blocks)
499 schedule_delayed_work(&tcmu_unmap_work, 0);
500
501
502 page = alloc_page(GFP_KERNEL);
503 if (!page)
504 goto err_alloc;
505
506 ret = radix_tree_insert(&udev->data_blocks, dbi, page);
507 if (ret)
508 goto err_insert;
509 }
510
511 if (dbi > udev->dbi_max)
512 udev->dbi_max = dbi;
513
514 set_bit(dbi, udev->data_bitmap);
515 tcmu_cmd_set_dbi(tcmu_cmd, dbi);
516
517 return true;
518err_insert:
519 __free_page(page);
520err_alloc:
521 atomic_dec(&global_db_count);
522 return false;
523}
524
525static bool tcmu_get_empty_blocks(struct tcmu_dev *udev,
526 struct tcmu_cmd *tcmu_cmd)
527{
528 int i;
529
530 for (i = tcmu_cmd->dbi_cur; i < tcmu_cmd->dbi_cnt; i++) {
531 if (!tcmu_get_empty_block(udev, tcmu_cmd))
532 return false;
533 }
534 return true;
535}
536
537static inline struct page *
538tcmu_get_block_page(struct tcmu_dev *udev, uint32_t dbi)
539{
540 return radix_tree_lookup(&udev->data_blocks, dbi);
541}
542
543static inline void tcmu_free_cmd(struct tcmu_cmd *tcmu_cmd)
544{
545 kfree(tcmu_cmd->dbi);
546 kmem_cache_free(tcmu_cmd_cache, tcmu_cmd);
547}
548
549static inline size_t tcmu_cmd_get_data_length(struct tcmu_cmd *tcmu_cmd)
550{
551 struct se_cmd *se_cmd = tcmu_cmd->se_cmd;
552 size_t data_length = round_up(se_cmd->data_length, DATA_BLOCK_SIZE);
553
554 if (se_cmd->se_cmd_flags & SCF_BIDI) {
555 BUG_ON(!(se_cmd->t_bidi_data_sg && se_cmd->t_bidi_data_nents));
556 data_length += round_up(se_cmd->t_bidi_data_sg->length,
557 DATA_BLOCK_SIZE);
558 }
559
560 return data_length;
561}
562
563static inline uint32_t tcmu_cmd_get_block_cnt(struct tcmu_cmd *tcmu_cmd)
564{
565 size_t data_length = tcmu_cmd_get_data_length(tcmu_cmd);
566
567 return data_length / DATA_BLOCK_SIZE;
568}
569
570static struct tcmu_cmd *tcmu_alloc_cmd(struct se_cmd *se_cmd)
571{
572 struct se_device *se_dev = se_cmd->se_dev;
573 struct tcmu_dev *udev = TCMU_DEV(se_dev);
574 struct tcmu_cmd *tcmu_cmd;
575
576 tcmu_cmd = kmem_cache_zalloc(tcmu_cmd_cache, GFP_KERNEL);
577 if (!tcmu_cmd)
578 return NULL;
579
580 INIT_LIST_HEAD(&tcmu_cmd->queue_entry);
581 tcmu_cmd->se_cmd = se_cmd;
582 tcmu_cmd->tcmu_dev = udev;
583
584 tcmu_cmd_reset_dbi_cur(tcmu_cmd);
585 tcmu_cmd->dbi_cnt = tcmu_cmd_get_block_cnt(tcmu_cmd);
586 tcmu_cmd->dbi = kcalloc(tcmu_cmd->dbi_cnt, sizeof(uint32_t),
587 GFP_KERNEL);
588 if (!tcmu_cmd->dbi) {
589 kmem_cache_free(tcmu_cmd_cache, tcmu_cmd);
590 return NULL;
591 }
592
593 return tcmu_cmd;
594}
595
596static inline void tcmu_flush_dcache_range(void *vaddr, size_t size)
597{
598 unsigned long offset = offset_in_page(vaddr);
599 void *start = vaddr - offset;
600
601 size = round_up(size+offset, PAGE_SIZE);
602
603 while (size) {
604 flush_dcache_page(virt_to_page(start));
605 start += PAGE_SIZE;
606 size -= PAGE_SIZE;
607 }
608}
609
610
611
612
613
614static inline size_t spc_used(size_t head, size_t tail, size_t size)
615{
616 int diff = head - tail;
617
618 if (diff >= 0)
619 return diff;
620 else
621 return size + diff;
622}
623
624static inline size_t spc_free(size_t head, size_t tail, size_t size)
625{
626
627 return (size - spc_used(head, tail, size) - 1);
628}
629
630static inline size_t head_to_end(size_t head, size_t size)
631{
632 return size - head;
633}
634
635static inline void new_iov(struct iovec **iov, int *iov_cnt)
636{
637 struct iovec *iovec;
638
639 if (*iov_cnt != 0)
640 (*iov)++;
641 (*iov_cnt)++;
642
643 iovec = *iov;
644 memset(iovec, 0, sizeof(struct iovec));
645}
646
647#define UPDATE_HEAD(head, used, size) smp_store_release(&head, ((head % size) + used) % size)
648
649
650static inline size_t get_block_offset_user(struct tcmu_dev *dev,
651 int dbi, int remaining)
652{
653 return dev->data_off + dbi * DATA_BLOCK_SIZE +
654 DATA_BLOCK_SIZE - remaining;
655}
656
657static inline size_t iov_tail(struct iovec *iov)
658{
659 return (size_t)iov->iov_base + iov->iov_len;
660}
661
662static void scatter_data_area(struct tcmu_dev *udev,
663 struct tcmu_cmd *tcmu_cmd, struct scatterlist *data_sg,
664 unsigned int data_nents, struct iovec **iov,
665 int *iov_cnt, bool copy_data)
666{
667 int i, dbi;
668 int block_remaining = 0;
669 void *from, *to = NULL;
670 size_t copy_bytes, to_offset, offset;
671 struct scatterlist *sg;
672 struct page *page;
673
674 for_each_sg(data_sg, sg, data_nents, i) {
675 int sg_remaining = sg->length;
676 from = kmap_atomic(sg_page(sg)) + sg->offset;
677 while (sg_remaining > 0) {
678 if (block_remaining == 0) {
679 if (to)
680 kunmap_atomic(to);
681
682 block_remaining = DATA_BLOCK_SIZE;
683 dbi = tcmu_cmd_get_dbi(tcmu_cmd);
684 page = tcmu_get_block_page(udev, dbi);
685 to = kmap_atomic(page);
686 }
687
688
689
690
691 to_offset = get_block_offset_user(udev, dbi,
692 block_remaining);
693
694
695
696
697
698
699 copy_bytes = min_t(size_t, sg_remaining,
700 block_remaining);
701 if (*iov_cnt != 0 &&
702 to_offset == iov_tail(*iov)) {
703
704
705
706
707
708 (*iov)->iov_len += copy_bytes;
709 } else {
710
711
712
713
714
715 new_iov(iov, iov_cnt);
716 (*iov)->iov_base = (void __user *)to_offset;
717 (*iov)->iov_len = copy_bytes;
718 }
719
720 if (copy_data) {
721 offset = DATA_BLOCK_SIZE - block_remaining;
722 memcpy(to + offset,
723 from + sg->length - sg_remaining,
724 copy_bytes);
725 tcmu_flush_dcache_range(to, copy_bytes);
726 }
727
728 sg_remaining -= copy_bytes;
729 block_remaining -= copy_bytes;
730 }
731 kunmap_atomic(from - sg->offset);
732 }
733
734 if (to)
735 kunmap_atomic(to);
736}
737
738static void gather_data_area(struct tcmu_dev *udev, struct tcmu_cmd *cmd,
739 bool bidi, uint32_t read_len)
740{
741 struct se_cmd *se_cmd = cmd->se_cmd;
742 int i, dbi;
743 int block_remaining = 0;
744 void *from = NULL, *to;
745 size_t copy_bytes, offset;
746 struct scatterlist *sg, *data_sg;
747 struct page *page;
748 unsigned int data_nents;
749 uint32_t count = 0;
750
751 if (!bidi) {
752 data_sg = se_cmd->t_data_sg;
753 data_nents = se_cmd->t_data_nents;
754 } else {
755
756
757
758
759
760
761 count = DIV_ROUND_UP(se_cmd->data_length, DATA_BLOCK_SIZE);
762
763 data_sg = se_cmd->t_bidi_data_sg;
764 data_nents = se_cmd->t_bidi_data_nents;
765 }
766
767 tcmu_cmd_set_dbi_cur(cmd, count);
768
769 for_each_sg(data_sg, sg, data_nents, i) {
770 int sg_remaining = sg->length;
771 to = kmap_atomic(sg_page(sg)) + sg->offset;
772 while (sg_remaining > 0 && read_len > 0) {
773 if (block_remaining == 0) {
774 if (from)
775 kunmap_atomic(from);
776
777 block_remaining = DATA_BLOCK_SIZE;
778 dbi = tcmu_cmd_get_dbi(cmd);
779 page = tcmu_get_block_page(udev, dbi);
780 from = kmap_atomic(page);
781 }
782 copy_bytes = min_t(size_t, sg_remaining,
783 block_remaining);
784 if (read_len < copy_bytes)
785 copy_bytes = read_len;
786 offset = DATA_BLOCK_SIZE - block_remaining;
787 tcmu_flush_dcache_range(from, copy_bytes);
788 memcpy(to + sg->length - sg_remaining, from + offset,
789 copy_bytes);
790
791 sg_remaining -= copy_bytes;
792 block_remaining -= copy_bytes;
793 read_len -= copy_bytes;
794 }
795 kunmap_atomic(to - sg->offset);
796 if (read_len == 0)
797 break;
798 }
799 if (from)
800 kunmap_atomic(from);
801}
802
803static inline size_t spc_bitmap_free(unsigned long *bitmap, uint32_t thresh)
804{
805 return thresh - bitmap_weight(bitmap, thresh);
806}
807
808
809
810
811
812
813
814static bool is_ring_space_avail(struct tcmu_dev *udev, struct tcmu_cmd *cmd,
815 size_t cmd_size, size_t data_needed)
816{
817 struct tcmu_mailbox *mb = udev->mb_addr;
818 uint32_t blocks_needed = (data_needed + DATA_BLOCK_SIZE - 1)
819 / DATA_BLOCK_SIZE;
820 size_t space, cmd_needed;
821 u32 cmd_head;
822
823 tcmu_flush_dcache_range(mb, sizeof(*mb));
824
825 cmd_head = mb->cmd_head % udev->cmdr_size;
826
827
828
829
830
831 if (head_to_end(cmd_head, udev->cmdr_size) >= cmd_size)
832 cmd_needed = cmd_size;
833 else
834 cmd_needed = cmd_size + head_to_end(cmd_head, udev->cmdr_size);
835
836 space = spc_free(cmd_head, udev->cmdr_last_cleaned, udev->cmdr_size);
837 if (space < cmd_needed) {
838 pr_debug("no cmd space: %u %u %u\n", cmd_head,
839 udev->cmdr_last_cleaned, udev->cmdr_size);
840 return false;
841 }
842
843
844 space = spc_bitmap_free(udev->data_bitmap, udev->dbi_thresh);
845 if ((space * DATA_BLOCK_SIZE) < data_needed) {
846 unsigned long blocks_left =
847 (udev->max_blocks - udev->dbi_thresh) + space;
848
849 if (blocks_left < blocks_needed) {
850 pr_debug("no data space: only %lu available, but ask for %zu\n",
851 blocks_left * DATA_BLOCK_SIZE,
852 data_needed);
853 return false;
854 }
855
856 udev->dbi_thresh += blocks_needed;
857 if (udev->dbi_thresh > udev->max_blocks)
858 udev->dbi_thresh = udev->max_blocks;
859 }
860
861 return tcmu_get_empty_blocks(udev, cmd);
862}
863
864static inline size_t tcmu_cmd_get_base_cmd_size(size_t iov_cnt)
865{
866 return max(offsetof(struct tcmu_cmd_entry, req.iov[iov_cnt]),
867 sizeof(struct tcmu_cmd_entry));
868}
869
870static inline size_t tcmu_cmd_get_cmd_size(struct tcmu_cmd *tcmu_cmd,
871 size_t base_command_size)
872{
873 struct se_cmd *se_cmd = tcmu_cmd->se_cmd;
874 size_t command_size;
875
876 command_size = base_command_size +
877 round_up(scsi_command_size(se_cmd->t_task_cdb),
878 TCMU_OP_ALIGN_SIZE);
879
880 WARN_ON(command_size & (TCMU_OP_ALIGN_SIZE-1));
881
882 return command_size;
883}
884
885static int tcmu_setup_cmd_timer(struct tcmu_cmd *tcmu_cmd, unsigned int tmo,
886 struct timer_list *timer)
887{
888 struct tcmu_dev *udev = tcmu_cmd->tcmu_dev;
889 int cmd_id;
890
891 if (tcmu_cmd->cmd_id)
892 goto setup_timer;
893
894 cmd_id = idr_alloc(&udev->commands, tcmu_cmd, 1, USHRT_MAX, GFP_NOWAIT);
895 if (cmd_id < 0) {
896 pr_err("tcmu: Could not allocate cmd id.\n");
897 return cmd_id;
898 }
899 tcmu_cmd->cmd_id = cmd_id;
900
901 pr_debug("allocated cmd %u for dev %s tmo %lu\n", tcmu_cmd->cmd_id,
902 udev->name, tmo / MSEC_PER_SEC);
903
904setup_timer:
905 if (!tmo)
906 return 0;
907
908 tcmu_cmd->deadline = round_jiffies_up(jiffies + msecs_to_jiffies(tmo));
909 if (!timer_pending(timer))
910 mod_timer(timer, tcmu_cmd->deadline);
911
912 return 0;
913}
914
915static int add_to_qfull_queue(struct tcmu_cmd *tcmu_cmd)
916{
917 struct tcmu_dev *udev = tcmu_cmd->tcmu_dev;
918 unsigned int tmo;
919 int ret;
920
921
922
923
924
925 if (!udev->qfull_time_out)
926 return -ETIMEDOUT;
927 else if (udev->qfull_time_out > 0)
928 tmo = udev->qfull_time_out;
929 else if (udev->cmd_time_out)
930 tmo = udev->cmd_time_out;
931 else
932 tmo = TCMU_TIME_OUT;
933
934 ret = tcmu_setup_cmd_timer(tcmu_cmd, tmo, &udev->qfull_timer);
935 if (ret)
936 return ret;
937
938 list_add_tail(&tcmu_cmd->queue_entry, &udev->qfull_queue);
939 pr_debug("adding cmd %u on dev %s to ring space wait queue\n",
940 tcmu_cmd->cmd_id, udev->name);
941 return 0;
942}
943
944
945
946
947
948
949
950
951
952
953
954static int queue_cmd_ring(struct tcmu_cmd *tcmu_cmd, sense_reason_t *scsi_err)
955{
956 struct tcmu_dev *udev = tcmu_cmd->tcmu_dev;
957 struct se_cmd *se_cmd = tcmu_cmd->se_cmd;
958 size_t base_command_size, command_size;
959 struct tcmu_mailbox *mb;
960 struct tcmu_cmd_entry *entry;
961 struct iovec *iov;
962 int iov_cnt, ret;
963 uint32_t cmd_head;
964 uint64_t cdb_off;
965 bool copy_to_data_area;
966 size_t data_length = tcmu_cmd_get_data_length(tcmu_cmd);
967
968 *scsi_err = TCM_NO_SENSE;
969
970 if (test_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags)) {
971 *scsi_err = TCM_LUN_BUSY;
972 return -1;
973 }
974
975 if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) {
976 *scsi_err = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
977 return -1;
978 }
979
980
981
982
983
984
985
986
987
988
989
990
991
992 base_command_size = tcmu_cmd_get_base_cmd_size(tcmu_cmd->dbi_cnt);
993 command_size = tcmu_cmd_get_cmd_size(tcmu_cmd, base_command_size);
994
995 if (!list_empty(&udev->qfull_queue))
996 goto queue;
997
998 mb = udev->mb_addr;
999 cmd_head = mb->cmd_head % udev->cmdr_size;
1000 if ((command_size > (udev->cmdr_size / 2)) ||
1001 data_length > udev->data_size) {
1002 pr_warn("TCMU: Request of size %zu/%zu is too big for %u/%zu "
1003 "cmd ring/data area\n", command_size, data_length,
1004 udev->cmdr_size, udev->data_size);
1005 *scsi_err = TCM_INVALID_CDB_FIELD;
1006 return -1;
1007 }
1008
1009 if (!is_ring_space_avail(udev, tcmu_cmd, command_size, data_length)) {
1010
1011
1012
1013
1014 tcmu_cmd_free_data(tcmu_cmd, tcmu_cmd->dbi_cur);
1015 tcmu_cmd_reset_dbi_cur(tcmu_cmd);
1016 goto queue;
1017 }
1018
1019
1020 if (head_to_end(cmd_head, udev->cmdr_size) < command_size) {
1021 size_t pad_size = head_to_end(cmd_head, udev->cmdr_size);
1022
1023 entry = (void *) mb + CMDR_OFF + cmd_head;
1024 tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_PAD);
1025 tcmu_hdr_set_len(&entry->hdr.len_op, pad_size);
1026 entry->hdr.cmd_id = 0;
1027 entry->hdr.kflags = 0;
1028 entry->hdr.uflags = 0;
1029 tcmu_flush_dcache_range(entry, sizeof(*entry));
1030
1031 UPDATE_HEAD(mb->cmd_head, pad_size, udev->cmdr_size);
1032 tcmu_flush_dcache_range(mb, sizeof(*mb));
1033
1034 cmd_head = mb->cmd_head % udev->cmdr_size;
1035 WARN_ON(cmd_head != 0);
1036 }
1037
1038 entry = (void *) mb + CMDR_OFF + cmd_head;
1039 memset(entry, 0, command_size);
1040 tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_CMD);
1041
1042
1043 tcmu_cmd_reset_dbi_cur(tcmu_cmd);
1044 iov = &entry->req.iov[0];
1045 iov_cnt = 0;
1046 copy_to_data_area = (se_cmd->data_direction == DMA_TO_DEVICE
1047 || se_cmd->se_cmd_flags & SCF_BIDI);
1048 scatter_data_area(udev, tcmu_cmd, se_cmd->t_data_sg,
1049 se_cmd->t_data_nents, &iov, &iov_cnt,
1050 copy_to_data_area);
1051 entry->req.iov_cnt = iov_cnt;
1052
1053
1054 iov_cnt = 0;
1055 if (se_cmd->se_cmd_flags & SCF_BIDI) {
1056 iov++;
1057 scatter_data_area(udev, tcmu_cmd, se_cmd->t_bidi_data_sg,
1058 se_cmd->t_bidi_data_nents, &iov, &iov_cnt,
1059 false);
1060 }
1061 entry->req.iov_bidi_cnt = iov_cnt;
1062
1063 ret = tcmu_setup_cmd_timer(tcmu_cmd, udev->cmd_time_out,
1064 &udev->cmd_timer);
1065 if (ret) {
1066 tcmu_cmd_free_data(tcmu_cmd, tcmu_cmd->dbi_cnt);
1067
1068 *scsi_err = TCM_OUT_OF_RESOURCES;
1069 return -1;
1070 }
1071 entry->hdr.cmd_id = tcmu_cmd->cmd_id;
1072
1073
1074
1075
1076
1077 base_command_size = tcmu_cmd_get_base_cmd_size(entry->req.iov_cnt +
1078 entry->req.iov_bidi_cnt);
1079 command_size = tcmu_cmd_get_cmd_size(tcmu_cmd, base_command_size);
1080
1081 tcmu_hdr_set_len(&entry->hdr.len_op, command_size);
1082
1083
1084 cdb_off = CMDR_OFF + cmd_head + base_command_size;
1085 memcpy((void *) mb + cdb_off, se_cmd->t_task_cdb, scsi_command_size(se_cmd->t_task_cdb));
1086 entry->req.cdb_off = cdb_off;
1087 tcmu_flush_dcache_range(entry, sizeof(*entry));
1088
1089 UPDATE_HEAD(mb->cmd_head, command_size, udev->cmdr_size);
1090 tcmu_flush_dcache_range(mb, sizeof(*mb));
1091
1092 list_add_tail(&tcmu_cmd->queue_entry, &udev->inflight_queue);
1093 set_bit(TCMU_CMD_BIT_INFLIGHT, &tcmu_cmd->flags);
1094
1095
1096 uio_event_notify(&udev->uio_info);
1097
1098 return 0;
1099
1100queue:
1101 if (add_to_qfull_queue(tcmu_cmd)) {
1102 *scsi_err = TCM_OUT_OF_RESOURCES;
1103 return -1;
1104 }
1105
1106 return 1;
1107}
1108
1109static sense_reason_t
1110tcmu_queue_cmd(struct se_cmd *se_cmd)
1111{
1112 struct se_device *se_dev = se_cmd->se_dev;
1113 struct tcmu_dev *udev = TCMU_DEV(se_dev);
1114 struct tcmu_cmd *tcmu_cmd;
1115 sense_reason_t scsi_ret;
1116 int ret;
1117
1118 tcmu_cmd = tcmu_alloc_cmd(se_cmd);
1119 if (!tcmu_cmd)
1120 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1121
1122 mutex_lock(&udev->cmdr_lock);
1123 ret = queue_cmd_ring(tcmu_cmd, &scsi_ret);
1124 mutex_unlock(&udev->cmdr_lock);
1125 if (ret < 0)
1126 tcmu_free_cmd(tcmu_cmd);
1127 return scsi_ret;
1128}
1129
1130static void tcmu_handle_completion(struct tcmu_cmd *cmd, struct tcmu_cmd_entry *entry)
1131{
1132 struct se_cmd *se_cmd = cmd->se_cmd;
1133 struct tcmu_dev *udev = cmd->tcmu_dev;
1134 bool read_len_valid = false;
1135 uint32_t read_len;
1136
1137
1138
1139
1140
1141 if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) {
1142 WARN_ON_ONCE(se_cmd);
1143 goto out;
1144 }
1145
1146 list_del_init(&cmd->queue_entry);
1147
1148 tcmu_cmd_reset_dbi_cur(cmd);
1149
1150 if (entry->hdr.uflags & TCMU_UFLAG_UNKNOWN_OP) {
1151 pr_warn("TCMU: Userspace set UNKNOWN_OP flag on se_cmd %p\n",
1152 cmd->se_cmd);
1153 entry->rsp.scsi_status = SAM_STAT_CHECK_CONDITION;
1154 goto done;
1155 }
1156
1157 read_len = se_cmd->data_length;
1158 if (se_cmd->data_direction == DMA_FROM_DEVICE &&
1159 (entry->hdr.uflags & TCMU_UFLAG_READ_LEN) && entry->rsp.read_len) {
1160 read_len_valid = true;
1161 if (entry->rsp.read_len < read_len)
1162 read_len = entry->rsp.read_len;
1163 }
1164
1165 if (entry->rsp.scsi_status == SAM_STAT_CHECK_CONDITION) {
1166 transport_copy_sense_to_cmd(se_cmd, entry->rsp.sense_buffer);
1167 if (!read_len_valid )
1168 goto done;
1169 else
1170 se_cmd->se_cmd_flags |= SCF_TREAT_READ_AS_NORMAL;
1171 }
1172 if (se_cmd->se_cmd_flags & SCF_BIDI) {
1173
1174 gather_data_area(udev, cmd, true, read_len);
1175 } else if (se_cmd->data_direction == DMA_FROM_DEVICE) {
1176 gather_data_area(udev, cmd, false, read_len);
1177 } else if (se_cmd->data_direction == DMA_TO_DEVICE) {
1178
1179 } else if (se_cmd->data_direction != DMA_NONE) {
1180 pr_warn("TCMU: data direction was %d!\n",
1181 se_cmd->data_direction);
1182 }
1183
1184done:
1185 if (read_len_valid) {
1186 pr_debug("read_len = %d\n", read_len);
1187 target_complete_cmd_with_length(cmd->se_cmd,
1188 entry->rsp.scsi_status, read_len);
1189 } else
1190 target_complete_cmd(cmd->se_cmd, entry->rsp.scsi_status);
1191
1192out:
1193 cmd->se_cmd = NULL;
1194 tcmu_cmd_free_data(cmd, cmd->dbi_cnt);
1195 tcmu_free_cmd(cmd);
1196}
1197
1198static void tcmu_set_next_deadline(struct list_head *queue,
1199 struct timer_list *timer)
1200{
1201 struct tcmu_cmd *tcmu_cmd, *tmp_cmd;
1202 unsigned long deadline = 0;
1203
1204 list_for_each_entry_safe(tcmu_cmd, tmp_cmd, queue, queue_entry) {
1205 if (!time_after(jiffies, tcmu_cmd->deadline)) {
1206 deadline = tcmu_cmd->deadline;
1207 break;
1208 }
1209 }
1210
1211 if (deadline)
1212 mod_timer(timer, deadline);
1213 else
1214 del_timer(timer);
1215}
1216
1217static unsigned int tcmu_handle_completions(struct tcmu_dev *udev)
1218{
1219 struct tcmu_mailbox *mb;
1220 struct tcmu_cmd *cmd;
1221 int handled = 0;
1222
1223 if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) {
1224 pr_err("ring broken, not handling completions\n");
1225 return 0;
1226 }
1227
1228 mb = udev->mb_addr;
1229 tcmu_flush_dcache_range(mb, sizeof(*mb));
1230
1231 while (udev->cmdr_last_cleaned != READ_ONCE(mb->cmd_tail)) {
1232
1233 struct tcmu_cmd_entry *entry = (void *) mb + CMDR_OFF + udev->cmdr_last_cleaned;
1234
1235 tcmu_flush_dcache_range(entry, sizeof(*entry));
1236
1237 if (tcmu_hdr_get_op(entry->hdr.len_op) == TCMU_OP_PAD) {
1238 UPDATE_HEAD(udev->cmdr_last_cleaned,
1239 tcmu_hdr_get_len(entry->hdr.len_op),
1240 udev->cmdr_size);
1241 continue;
1242 }
1243 WARN_ON(tcmu_hdr_get_op(entry->hdr.len_op) != TCMU_OP_CMD);
1244
1245 cmd = idr_remove(&udev->commands, entry->hdr.cmd_id);
1246 if (!cmd) {
1247 pr_err("cmd_id %u not found, ring is broken\n",
1248 entry->hdr.cmd_id);
1249 set_bit(TCMU_DEV_BIT_BROKEN, &udev->flags);
1250 break;
1251 }
1252
1253 tcmu_handle_completion(cmd, entry);
1254
1255 UPDATE_HEAD(udev->cmdr_last_cleaned,
1256 tcmu_hdr_get_len(entry->hdr.len_op),
1257 udev->cmdr_size);
1258
1259 handled++;
1260 }
1261
1262 if (mb->cmd_tail == mb->cmd_head) {
1263
1264 del_timer(&udev->cmd_timer);
1265
1266 if (list_empty(&udev->qfull_queue)) {
1267
1268
1269
1270
1271 if (atomic_read(&global_db_count) >
1272 tcmu_global_max_blocks)
1273 schedule_delayed_work(&tcmu_unmap_work, 0);
1274 }
1275 } else if (udev->cmd_time_out) {
1276 tcmu_set_next_deadline(&udev->inflight_queue, &udev->cmd_timer);
1277 }
1278
1279 return handled;
1280}
1281
1282static int tcmu_check_expired_cmd(int id, void *p, void *data)
1283{
1284 struct tcmu_cmd *cmd = p;
1285 struct tcmu_dev *udev = cmd->tcmu_dev;
1286 u8 scsi_status;
1287 struct se_cmd *se_cmd;
1288 bool is_running;
1289
1290 if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags))
1291 return 0;
1292
1293 if (!time_after(jiffies, cmd->deadline))
1294 return 0;
1295
1296 is_running = test_bit(TCMU_CMD_BIT_INFLIGHT, &cmd->flags);
1297 se_cmd = cmd->se_cmd;
1298
1299 if (is_running) {
1300
1301
1302
1303
1304 if (!udev->cmd_time_out)
1305 return 0;
1306
1307 set_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags);
1308
1309
1310
1311 scsi_status = SAM_STAT_CHECK_CONDITION;
1312 list_del_init(&cmd->queue_entry);
1313 cmd->se_cmd = NULL;
1314 } else {
1315 list_del_init(&cmd->queue_entry);
1316 idr_remove(&udev->commands, id);
1317 tcmu_free_cmd(cmd);
1318 scsi_status = SAM_STAT_TASK_SET_FULL;
1319 }
1320
1321 pr_debug("Timing out cmd %u on dev %s that is %s.\n",
1322 id, udev->name, is_running ? "inflight" : "queued");
1323
1324 target_complete_cmd(se_cmd, scsi_status);
1325 return 0;
1326}
1327
1328static void tcmu_device_timedout(struct tcmu_dev *udev)
1329{
1330 spin_lock(&timed_out_udevs_lock);
1331 if (list_empty(&udev->timedout_entry))
1332 list_add_tail(&udev->timedout_entry, &timed_out_udevs);
1333 spin_unlock(&timed_out_udevs_lock);
1334
1335 schedule_delayed_work(&tcmu_unmap_work, 0);
1336}
1337
1338static void tcmu_cmd_timedout(struct timer_list *t)
1339{
1340 struct tcmu_dev *udev = from_timer(udev, t, cmd_timer);
1341
1342 pr_debug("%s cmd timeout has expired\n", udev->name);
1343 tcmu_device_timedout(udev);
1344}
1345
1346static void tcmu_qfull_timedout(struct timer_list *t)
1347{
1348 struct tcmu_dev *udev = from_timer(udev, t, qfull_timer);
1349
1350 pr_debug("%s qfull timeout has expired\n", udev->name);
1351 tcmu_device_timedout(udev);
1352}
1353
1354static int tcmu_attach_hba(struct se_hba *hba, u32 host_id)
1355{
1356 struct tcmu_hba *tcmu_hba;
1357
1358 tcmu_hba = kzalloc(sizeof(struct tcmu_hba), GFP_KERNEL);
1359 if (!tcmu_hba)
1360 return -ENOMEM;
1361
1362 tcmu_hba->host_id = host_id;
1363 hba->hba_ptr = tcmu_hba;
1364
1365 return 0;
1366}
1367
1368static void tcmu_detach_hba(struct se_hba *hba)
1369{
1370 kfree(hba->hba_ptr);
1371 hba->hba_ptr = NULL;
1372}
1373
1374static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name)
1375{
1376 struct tcmu_dev *udev;
1377
1378 udev = kzalloc(sizeof(struct tcmu_dev), GFP_KERNEL);
1379 if (!udev)
1380 return NULL;
1381 kref_init(&udev->kref);
1382
1383 udev->name = kstrdup(name, GFP_KERNEL);
1384 if (!udev->name) {
1385 kfree(udev);
1386 return NULL;
1387 }
1388
1389 udev->hba = hba;
1390 udev->cmd_time_out = TCMU_TIME_OUT;
1391 udev->qfull_time_out = -1;
1392
1393 udev->max_blocks = DATA_BLOCK_BITS_DEF;
1394 mutex_init(&udev->cmdr_lock);
1395
1396 INIT_LIST_HEAD(&udev->node);
1397 INIT_LIST_HEAD(&udev->timedout_entry);
1398 INIT_LIST_HEAD(&udev->qfull_queue);
1399 INIT_LIST_HEAD(&udev->inflight_queue);
1400 idr_init(&udev->commands);
1401
1402 timer_setup(&udev->qfull_timer, tcmu_qfull_timedout, 0);
1403 timer_setup(&udev->cmd_timer, tcmu_cmd_timedout, 0);
1404
1405 INIT_RADIX_TREE(&udev->data_blocks, GFP_KERNEL);
1406
1407 return &udev->se_dev;
1408}
1409
1410static bool run_qfull_queue(struct tcmu_dev *udev, bool fail)
1411{
1412 struct tcmu_cmd *tcmu_cmd, *tmp_cmd;
1413 LIST_HEAD(cmds);
1414 bool drained = true;
1415 sense_reason_t scsi_ret;
1416 int ret;
1417
1418 if (list_empty(&udev->qfull_queue))
1419 return true;
1420
1421 pr_debug("running %s's cmdr queue forcefail %d\n", udev->name, fail);
1422
1423 list_splice_init(&udev->qfull_queue, &cmds);
1424
1425 list_for_each_entry_safe(tcmu_cmd, tmp_cmd, &cmds, queue_entry) {
1426 list_del_init(&tcmu_cmd->queue_entry);
1427
1428 pr_debug("removing cmd %u on dev %s from queue\n",
1429 tcmu_cmd->cmd_id, udev->name);
1430
1431 if (fail) {
1432 idr_remove(&udev->commands, tcmu_cmd->cmd_id);
1433
1434
1435
1436
1437
1438
1439
1440 target_complete_cmd(tcmu_cmd->se_cmd, SAM_STAT_BUSY);
1441 tcmu_free_cmd(tcmu_cmd);
1442 continue;
1443 }
1444
1445 ret = queue_cmd_ring(tcmu_cmd, &scsi_ret);
1446 if (ret < 0) {
1447 pr_debug("cmd %u on dev %s failed with %u\n",
1448 tcmu_cmd->cmd_id, udev->name, scsi_ret);
1449
1450 idr_remove(&udev->commands, tcmu_cmd->cmd_id);
1451
1452
1453
1454
1455 target_complete_cmd(tcmu_cmd->se_cmd,
1456 SAM_STAT_CHECK_CONDITION);
1457 tcmu_free_cmd(tcmu_cmd);
1458 } else if (ret > 0) {
1459 pr_debug("ran out of space during cmdr queue run\n");
1460
1461
1462
1463
1464 list_splice_tail(&cmds, &udev->qfull_queue);
1465 drained = false;
1466 break;
1467 }
1468 }
1469
1470 tcmu_set_next_deadline(&udev->qfull_queue, &udev->qfull_timer);
1471 return drained;
1472}
1473
1474static int tcmu_irqcontrol(struct uio_info *info, s32 irq_on)
1475{
1476 struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info);
1477
1478 mutex_lock(&udev->cmdr_lock);
1479 tcmu_handle_completions(udev);
1480 run_qfull_queue(udev, false);
1481 mutex_unlock(&udev->cmdr_lock);
1482
1483 return 0;
1484}
1485
1486
1487
1488
1489
1490static int tcmu_find_mem_index(struct vm_area_struct *vma)
1491{
1492 struct tcmu_dev *udev = vma->vm_private_data;
1493 struct uio_info *info = &udev->uio_info;
1494
1495 if (vma->vm_pgoff < MAX_UIO_MAPS) {
1496 if (info->mem[vma->vm_pgoff].size == 0)
1497 return -1;
1498 return (int)vma->vm_pgoff;
1499 }
1500 return -1;
1501}
1502
1503static struct page *tcmu_try_get_block_page(struct tcmu_dev *udev, uint32_t dbi)
1504{
1505 struct page *page;
1506
1507 mutex_lock(&udev->cmdr_lock);
1508 page = tcmu_get_block_page(udev, dbi);
1509 if (likely(page)) {
1510 mutex_unlock(&udev->cmdr_lock);
1511 return page;
1512 }
1513
1514
1515
1516
1517
1518 pr_err("Invalid addr to data block mapping (dbi %u) on device %s\n",
1519 dbi, udev->name);
1520 page = NULL;
1521 mutex_unlock(&udev->cmdr_lock);
1522
1523 return page;
1524}
1525
1526static vm_fault_t tcmu_vma_fault(struct vm_fault *vmf)
1527{
1528 struct tcmu_dev *udev = vmf->vma->vm_private_data;
1529 struct uio_info *info = &udev->uio_info;
1530 struct page *page;
1531 unsigned long offset;
1532 void *addr;
1533
1534 int mi = tcmu_find_mem_index(vmf->vma);
1535 if (mi < 0)
1536 return VM_FAULT_SIGBUS;
1537
1538
1539
1540
1541
1542 offset = (vmf->pgoff - mi) << PAGE_SHIFT;
1543
1544 if (offset < udev->data_off) {
1545
1546 addr = (void *)(unsigned long)info->mem[mi].addr + offset;
1547 page = vmalloc_to_page(addr);
1548 } else {
1549 uint32_t dbi;
1550
1551
1552 dbi = (offset - udev->data_off) / DATA_BLOCK_SIZE;
1553 page = tcmu_try_get_block_page(udev, dbi);
1554 if (!page)
1555 return VM_FAULT_SIGBUS;
1556 }
1557
1558 get_page(page);
1559 vmf->page = page;
1560 return 0;
1561}
1562
1563static const struct vm_operations_struct tcmu_vm_ops = {
1564 .fault = tcmu_vma_fault,
1565};
1566
1567static int tcmu_mmap(struct uio_info *info, struct vm_area_struct *vma)
1568{
1569 struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info);
1570
1571 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
1572 vma->vm_ops = &tcmu_vm_ops;
1573
1574 vma->vm_private_data = udev;
1575
1576
1577 if (vma_pages(vma) != (udev->ring_size >> PAGE_SHIFT))
1578 return -EINVAL;
1579
1580 return 0;
1581}
1582
1583static int tcmu_open(struct uio_info *info, struct inode *inode)
1584{
1585 struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info);
1586
1587
1588 if (test_and_set_bit(TCMU_DEV_BIT_OPEN, &udev->flags))
1589 return -EBUSY;
1590
1591 udev->inode = inode;
1592 kref_get(&udev->kref);
1593
1594 pr_debug("open\n");
1595
1596 return 0;
1597}
1598
1599static void tcmu_dev_call_rcu(struct rcu_head *p)
1600{
1601 struct se_device *dev = container_of(p, struct se_device, rcu_head);
1602 struct tcmu_dev *udev = TCMU_DEV(dev);
1603
1604 kfree(udev->uio_info.name);
1605 kfree(udev->name);
1606 kfree(udev);
1607}
1608
1609static int tcmu_check_and_free_pending_cmd(struct tcmu_cmd *cmd)
1610{
1611 if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) {
1612 kmem_cache_free(tcmu_cmd_cache, cmd);
1613 return 0;
1614 }
1615 return -EINVAL;
1616}
1617
1618static void tcmu_blocks_release(struct radix_tree_root *blocks,
1619 int start, int end)
1620{
1621 int i;
1622 struct page *page;
1623
1624 for (i = start; i < end; i++) {
1625 page = radix_tree_delete(blocks, i);
1626 if (page) {
1627 __free_page(page);
1628 atomic_dec(&global_db_count);
1629 }
1630 }
1631}
1632
1633static void tcmu_dev_kref_release(struct kref *kref)
1634{
1635 struct tcmu_dev *udev = container_of(kref, struct tcmu_dev, kref);
1636 struct se_device *dev = &udev->se_dev;
1637 struct tcmu_cmd *cmd;
1638 bool all_expired = true;
1639 int i;
1640
1641 vfree(udev->mb_addr);
1642 udev->mb_addr = NULL;
1643
1644 spin_lock_bh(&timed_out_udevs_lock);
1645 if (!list_empty(&udev->timedout_entry))
1646 list_del(&udev->timedout_entry);
1647 spin_unlock_bh(&timed_out_udevs_lock);
1648
1649
1650 mutex_lock(&udev->cmdr_lock);
1651 idr_for_each_entry(&udev->commands, cmd, i) {
1652 if (tcmu_check_and_free_pending_cmd(cmd) != 0)
1653 all_expired = false;
1654 }
1655 idr_destroy(&udev->commands);
1656 WARN_ON(!all_expired);
1657
1658 tcmu_blocks_release(&udev->data_blocks, 0, udev->dbi_max + 1);
1659 bitmap_free(udev->data_bitmap);
1660 mutex_unlock(&udev->cmdr_lock);
1661
1662 call_rcu(&dev->rcu_head, tcmu_dev_call_rcu);
1663}
1664
1665static int tcmu_release(struct uio_info *info, struct inode *inode)
1666{
1667 struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info);
1668
1669 clear_bit(TCMU_DEV_BIT_OPEN, &udev->flags);
1670
1671 pr_debug("close\n");
1672
1673 kref_put(&udev->kref, tcmu_dev_kref_release);
1674 return 0;
1675}
1676
1677static int tcmu_init_genl_cmd_reply(struct tcmu_dev *udev, int cmd)
1678{
1679 struct tcmu_nl_cmd *nl_cmd = &udev->curr_nl_cmd;
1680
1681 if (!tcmu_kern_cmd_reply_supported)
1682 return 0;
1683
1684 if (udev->nl_reply_supported <= 0)
1685 return 0;
1686
1687 mutex_lock(&tcmu_nl_cmd_mutex);
1688
1689 if (tcmu_netlink_blocked) {
1690 mutex_unlock(&tcmu_nl_cmd_mutex);
1691 pr_warn("Failing nl cmd %d on %s. Interface is blocked.\n", cmd,
1692 udev->name);
1693 return -EAGAIN;
1694 }
1695
1696 if (nl_cmd->cmd != TCMU_CMD_UNSPEC) {
1697 mutex_unlock(&tcmu_nl_cmd_mutex);
1698 pr_warn("netlink cmd %d already executing on %s\n",
1699 nl_cmd->cmd, udev->name);
1700 return -EBUSY;
1701 }
1702
1703 memset(nl_cmd, 0, sizeof(*nl_cmd));
1704 nl_cmd->cmd = cmd;
1705 nl_cmd->udev = udev;
1706 init_completion(&nl_cmd->complete);
1707 INIT_LIST_HEAD(&nl_cmd->nl_list);
1708
1709 list_add_tail(&nl_cmd->nl_list, &tcmu_nl_cmd_list);
1710
1711 mutex_unlock(&tcmu_nl_cmd_mutex);
1712 return 0;
1713}
1714
1715static int tcmu_wait_genl_cmd_reply(struct tcmu_dev *udev)
1716{
1717 struct tcmu_nl_cmd *nl_cmd = &udev->curr_nl_cmd;
1718 int ret;
1719
1720 if (!tcmu_kern_cmd_reply_supported)
1721 return 0;
1722
1723 if (udev->nl_reply_supported <= 0)
1724 return 0;
1725
1726 pr_debug("sleeping for nl reply\n");
1727 wait_for_completion(&nl_cmd->complete);
1728
1729 mutex_lock(&tcmu_nl_cmd_mutex);
1730 nl_cmd->cmd = TCMU_CMD_UNSPEC;
1731 ret = nl_cmd->status;
1732 mutex_unlock(&tcmu_nl_cmd_mutex);
1733
1734 return ret;
1735}
1736
1737static int tcmu_netlink_event_init(struct tcmu_dev *udev,
1738 enum tcmu_genl_cmd cmd,
1739 struct sk_buff **buf, void **hdr)
1740{
1741 struct sk_buff *skb;
1742 void *msg_header;
1743 int ret = -ENOMEM;
1744
1745 skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
1746 if (!skb)
1747 return ret;
1748
1749 msg_header = genlmsg_put(skb, 0, 0, &tcmu_genl_family, 0, cmd);
1750 if (!msg_header)
1751 goto free_skb;
1752
1753 ret = nla_put_string(skb, TCMU_ATTR_DEVICE, udev->uio_info.name);
1754 if (ret < 0)
1755 goto free_skb;
1756
1757 ret = nla_put_u32(skb, TCMU_ATTR_MINOR, udev->uio_info.uio_dev->minor);
1758 if (ret < 0)
1759 goto free_skb;
1760
1761 ret = nla_put_u32(skb, TCMU_ATTR_DEVICE_ID, udev->se_dev.dev_index);
1762 if (ret < 0)
1763 goto free_skb;
1764
1765 *buf = skb;
1766 *hdr = msg_header;
1767 return ret;
1768
1769free_skb:
1770 nlmsg_free(skb);
1771 return ret;
1772}
1773
1774static int tcmu_netlink_event_send(struct tcmu_dev *udev,
1775 enum tcmu_genl_cmd cmd,
1776 struct sk_buff *skb, void *msg_header)
1777{
1778 int ret;
1779
1780 genlmsg_end(skb, msg_header);
1781
1782 ret = tcmu_init_genl_cmd_reply(udev, cmd);
1783 if (ret) {
1784 nlmsg_free(skb);
1785 return ret;
1786 }
1787
1788 ret = genlmsg_multicast_allns(&tcmu_genl_family, skb, 0,
1789 TCMU_MCGRP_CONFIG, GFP_KERNEL);
1790
1791
1792 if (ret == 0 ||
1793 (ret == -ESRCH && cmd == TCMU_CMD_ADDED_DEVICE))
1794 return tcmu_wait_genl_cmd_reply(udev);
1795
1796 return ret;
1797}
1798
1799static int tcmu_send_dev_add_event(struct tcmu_dev *udev)
1800{
1801 struct sk_buff *skb = NULL;
1802 void *msg_header = NULL;
1803 int ret = 0;
1804
1805 ret = tcmu_netlink_event_init(udev, TCMU_CMD_ADDED_DEVICE, &skb,
1806 &msg_header);
1807 if (ret < 0)
1808 return ret;
1809 return tcmu_netlink_event_send(udev, TCMU_CMD_ADDED_DEVICE, skb,
1810 msg_header);
1811}
1812
1813static int tcmu_send_dev_remove_event(struct tcmu_dev *udev)
1814{
1815 struct sk_buff *skb = NULL;
1816 void *msg_header = NULL;
1817 int ret = 0;
1818
1819 ret = tcmu_netlink_event_init(udev, TCMU_CMD_REMOVED_DEVICE,
1820 &skb, &msg_header);
1821 if (ret < 0)
1822 return ret;
1823 return tcmu_netlink_event_send(udev, TCMU_CMD_REMOVED_DEVICE,
1824 skb, msg_header);
1825}
1826
1827static int tcmu_update_uio_info(struct tcmu_dev *udev)
1828{
1829 struct tcmu_hba *hba = udev->hba->hba_ptr;
1830 struct uio_info *info;
1831 char *str;
1832
1833 info = &udev->uio_info;
1834
1835 if (udev->dev_config[0])
1836 str = kasprintf(GFP_KERNEL, "tcm-user/%u/%s/%s", hba->host_id,
1837 udev->name, udev->dev_config);
1838 else
1839 str = kasprintf(GFP_KERNEL, "tcm-user/%u/%s", hba->host_id,
1840 udev->name);
1841 if (!str)
1842 return -ENOMEM;
1843
1844
1845 kfree(info->name);
1846 info->name = str;
1847
1848 return 0;
1849}
1850
1851static int tcmu_configure_device(struct se_device *dev)
1852{
1853 struct tcmu_dev *udev = TCMU_DEV(dev);
1854 struct uio_info *info;
1855 struct tcmu_mailbox *mb;
1856 int ret = 0;
1857
1858 ret = tcmu_update_uio_info(udev);
1859 if (ret)
1860 return ret;
1861
1862 info = &udev->uio_info;
1863
1864 mutex_lock(&udev->cmdr_lock);
1865 udev->data_bitmap = bitmap_zalloc(udev->max_blocks, GFP_KERNEL);
1866 mutex_unlock(&udev->cmdr_lock);
1867 if (!udev->data_bitmap) {
1868 ret = -ENOMEM;
1869 goto err_bitmap_alloc;
1870 }
1871
1872 udev->mb_addr = vzalloc(CMDR_SIZE);
1873 if (!udev->mb_addr) {
1874 ret = -ENOMEM;
1875 goto err_vzalloc;
1876 }
1877
1878
1879 udev->cmdr_size = CMDR_SIZE - CMDR_OFF;
1880 udev->data_off = CMDR_SIZE;
1881 udev->data_size = udev->max_blocks * DATA_BLOCK_SIZE;
1882 udev->dbi_thresh = 0;
1883
1884
1885 mb = udev->mb_addr;
1886 mb->version = TCMU_MAILBOX_VERSION;
1887 mb->flags = TCMU_MAILBOX_FLAG_CAP_OOOC | TCMU_MAILBOX_FLAG_CAP_READ_LEN;
1888 mb->cmdr_off = CMDR_OFF;
1889 mb->cmdr_size = udev->cmdr_size;
1890
1891 WARN_ON(!PAGE_ALIGNED(udev->data_off));
1892 WARN_ON(udev->data_size % PAGE_SIZE);
1893 WARN_ON(udev->data_size % DATA_BLOCK_SIZE);
1894
1895 info->version = __stringify(TCMU_MAILBOX_VERSION);
1896
1897 info->mem[0].name = "tcm-user command & data buffer";
1898 info->mem[0].addr = (phys_addr_t)(uintptr_t)udev->mb_addr;
1899 info->mem[0].size = udev->ring_size = udev->data_size + CMDR_SIZE;
1900 info->mem[0].memtype = UIO_MEM_NONE;
1901
1902 info->irqcontrol = tcmu_irqcontrol;
1903 info->irq = UIO_IRQ_CUSTOM;
1904
1905 info->mmap = tcmu_mmap;
1906 info->open = tcmu_open;
1907 info->release = tcmu_release;
1908
1909 ret = uio_register_device(tcmu_root_device, info);
1910 if (ret)
1911 goto err_register;
1912
1913
1914 if (dev->dev_attrib.hw_block_size == 0)
1915 dev->dev_attrib.hw_block_size = 512;
1916
1917 if (!dev->dev_attrib.hw_max_sectors)
1918 dev->dev_attrib.hw_max_sectors = 128;
1919 if (!dev->dev_attrib.emulate_write_cache)
1920 dev->dev_attrib.emulate_write_cache = 0;
1921 dev->dev_attrib.hw_queue_depth = 128;
1922
1923
1924
1925
1926 if (udev->nl_reply_supported >= 0)
1927 udev->nl_reply_supported = tcmu_kern_cmd_reply_supported;
1928
1929
1930
1931
1932
1933 kref_get(&udev->kref);
1934
1935 ret = tcmu_send_dev_add_event(udev);
1936 if (ret)
1937 goto err_netlink;
1938
1939 mutex_lock(&root_udev_mutex);
1940 list_add(&udev->node, &root_udev);
1941 mutex_unlock(&root_udev_mutex);
1942
1943 return 0;
1944
1945err_netlink:
1946 kref_put(&udev->kref, tcmu_dev_kref_release);
1947 uio_unregister_device(&udev->uio_info);
1948err_register:
1949 vfree(udev->mb_addr);
1950 udev->mb_addr = NULL;
1951err_vzalloc:
1952 bitmap_free(udev->data_bitmap);
1953 udev->data_bitmap = NULL;
1954err_bitmap_alloc:
1955 kfree(info->name);
1956 info->name = NULL;
1957
1958 return ret;
1959}
1960
1961static void tcmu_free_device(struct se_device *dev)
1962{
1963 struct tcmu_dev *udev = TCMU_DEV(dev);
1964
1965
1966 kref_put(&udev->kref, tcmu_dev_kref_release);
1967}
1968
1969static void tcmu_destroy_device(struct se_device *dev)
1970{
1971 struct tcmu_dev *udev = TCMU_DEV(dev);
1972
1973 del_timer_sync(&udev->cmd_timer);
1974 del_timer_sync(&udev->qfull_timer);
1975
1976 mutex_lock(&root_udev_mutex);
1977 list_del(&udev->node);
1978 mutex_unlock(&root_udev_mutex);
1979
1980 tcmu_send_dev_remove_event(udev);
1981
1982 uio_unregister_device(&udev->uio_info);
1983
1984
1985 kref_put(&udev->kref, tcmu_dev_kref_release);
1986}
1987
1988static void tcmu_unblock_dev(struct tcmu_dev *udev)
1989{
1990 mutex_lock(&udev->cmdr_lock);
1991 clear_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags);
1992 mutex_unlock(&udev->cmdr_lock);
1993}
1994
1995static void tcmu_block_dev(struct tcmu_dev *udev)
1996{
1997 mutex_lock(&udev->cmdr_lock);
1998
1999 if (test_and_set_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags))
2000 goto unlock;
2001
2002
2003 tcmu_handle_completions(udev);
2004
2005 run_qfull_queue(udev, true);
2006
2007unlock:
2008 mutex_unlock(&udev->cmdr_lock);
2009}
2010
2011static void tcmu_reset_ring(struct tcmu_dev *udev, u8 err_level)
2012{
2013 struct tcmu_mailbox *mb;
2014 struct tcmu_cmd *cmd;
2015 int i;
2016
2017 mutex_lock(&udev->cmdr_lock);
2018
2019 idr_for_each_entry(&udev->commands, cmd, i) {
2020 if (!test_bit(TCMU_CMD_BIT_INFLIGHT, &cmd->flags))
2021 continue;
2022
2023 pr_debug("removing cmd %u on dev %s from ring (is expired %d)\n",
2024 cmd->cmd_id, udev->name,
2025 test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags));
2026
2027 idr_remove(&udev->commands, i);
2028 if (!test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) {
2029 WARN_ON(!cmd->se_cmd);
2030 list_del_init(&cmd->queue_entry);
2031 if (err_level == 1) {
2032
2033
2034
2035
2036 target_complete_cmd(cmd->se_cmd, SAM_STAT_BUSY);
2037 } else {
2038
2039 target_complete_cmd(cmd->se_cmd,
2040 SAM_STAT_CHECK_CONDITION);
2041 }
2042 }
2043 tcmu_cmd_free_data(cmd, cmd->dbi_cnt);
2044 tcmu_free_cmd(cmd);
2045 }
2046
2047 mb = udev->mb_addr;
2048 tcmu_flush_dcache_range(mb, sizeof(*mb));
2049 pr_debug("mb last %u head %u tail %u\n", udev->cmdr_last_cleaned,
2050 mb->cmd_tail, mb->cmd_head);
2051
2052 udev->cmdr_last_cleaned = 0;
2053 mb->cmd_tail = 0;
2054 mb->cmd_head = 0;
2055 tcmu_flush_dcache_range(mb, sizeof(*mb));
2056
2057 del_timer(&udev->cmd_timer);
2058
2059 mutex_unlock(&udev->cmdr_lock);
2060}
2061
2062enum {
2063 Opt_dev_config, Opt_dev_size, Opt_hw_block_size, Opt_hw_max_sectors,
2064 Opt_nl_reply_supported, Opt_max_data_area_mb, Opt_err,
2065};
2066
2067static match_table_t tokens = {
2068 {Opt_dev_config, "dev_config=%s"},
2069 {Opt_dev_size, "dev_size=%s"},
2070 {Opt_hw_block_size, "hw_block_size=%d"},
2071 {Opt_hw_max_sectors, "hw_max_sectors=%d"},
2072 {Opt_nl_reply_supported, "nl_reply_supported=%d"},
2073 {Opt_max_data_area_mb, "max_data_area_mb=%d"},
2074 {Opt_err, NULL}
2075};
2076
2077static int tcmu_set_dev_attrib(substring_t *arg, u32 *dev_attrib)
2078{
2079 int val, ret;
2080
2081 ret = match_int(arg, &val);
2082 if (ret < 0) {
2083 pr_err("match_int() failed for dev attrib. Error %d.\n",
2084 ret);
2085 return ret;
2086 }
2087
2088 if (val <= 0) {
2089 pr_err("Invalid dev attrib value %d. Must be greater than zero.\n",
2090 val);
2091 return -EINVAL;
2092 }
2093 *dev_attrib = val;
2094 return 0;
2095}
2096
2097static int tcmu_set_max_blocks_param(struct tcmu_dev *udev, substring_t *arg)
2098{
2099 int val, ret;
2100
2101 ret = match_int(arg, &val);
2102 if (ret < 0) {
2103 pr_err("match_int() failed for max_data_area_mb=. Error %d.\n",
2104 ret);
2105 return ret;
2106 }
2107
2108 if (val <= 0) {
2109 pr_err("Invalid max_data_area %d.\n", val);
2110 return -EINVAL;
2111 }
2112
2113 mutex_lock(&udev->cmdr_lock);
2114 if (udev->data_bitmap) {
2115 pr_err("Cannot set max_data_area_mb after it has been enabled.\n");
2116 ret = -EINVAL;
2117 goto unlock;
2118 }
2119
2120 udev->max_blocks = TCMU_MBS_TO_BLOCKS(val);
2121 if (udev->max_blocks > tcmu_global_max_blocks) {
2122 pr_err("%d is too large. Adjusting max_data_area_mb to global limit of %u\n",
2123 val, TCMU_BLOCKS_TO_MBS(tcmu_global_max_blocks));
2124 udev->max_blocks = tcmu_global_max_blocks;
2125 }
2126
2127unlock:
2128 mutex_unlock(&udev->cmdr_lock);
2129 return ret;
2130}
2131
2132static ssize_t tcmu_set_configfs_dev_params(struct se_device *dev,
2133 const char *page, ssize_t count)
2134{
2135 struct tcmu_dev *udev = TCMU_DEV(dev);
2136 char *orig, *ptr, *opts;
2137 substring_t args[MAX_OPT_ARGS];
2138 int ret = 0, token;
2139
2140 opts = kstrdup(page, GFP_KERNEL);
2141 if (!opts)
2142 return -ENOMEM;
2143
2144 orig = opts;
2145
2146 while ((ptr = strsep(&opts, ",\n")) != NULL) {
2147 if (!*ptr)
2148 continue;
2149
2150 token = match_token(ptr, tokens, args);
2151 switch (token) {
2152 case Opt_dev_config:
2153 if (match_strlcpy(udev->dev_config, &args[0],
2154 TCMU_CONFIG_LEN) == 0) {
2155 ret = -EINVAL;
2156 break;
2157 }
2158 pr_debug("TCMU: Referencing Path: %s\n", udev->dev_config);
2159 break;
2160 case Opt_dev_size:
2161 ret = match_u64(&args[0], &udev->dev_size);
2162 if (ret < 0)
2163 pr_err("match_u64() failed for dev_size=. Error %d.\n",
2164 ret);
2165 break;
2166 case Opt_hw_block_size:
2167 ret = tcmu_set_dev_attrib(&args[0],
2168 &(dev->dev_attrib.hw_block_size));
2169 break;
2170 case Opt_hw_max_sectors:
2171 ret = tcmu_set_dev_attrib(&args[0],
2172 &(dev->dev_attrib.hw_max_sectors));
2173 break;
2174 case Opt_nl_reply_supported:
2175 ret = match_int(&args[0], &udev->nl_reply_supported);
2176 if (ret < 0)
2177 pr_err("match_int() failed for nl_reply_supported=. Error %d.\n",
2178 ret);
2179 break;
2180 case Opt_max_data_area_mb:
2181 ret = tcmu_set_max_blocks_param(udev, &args[0]);
2182 break;
2183 default:
2184 break;
2185 }
2186
2187 if (ret)
2188 break;
2189 }
2190
2191 kfree(orig);
2192 return (!ret) ? count : ret;
2193}
2194
2195static ssize_t tcmu_show_configfs_dev_params(struct se_device *dev, char *b)
2196{
2197 struct tcmu_dev *udev = TCMU_DEV(dev);
2198 ssize_t bl = 0;
2199
2200 bl = sprintf(b + bl, "Config: %s ",
2201 udev->dev_config[0] ? udev->dev_config : "NULL");
2202 bl += sprintf(b + bl, "Size: %llu ", udev->dev_size);
2203 bl += sprintf(b + bl, "MaxDataAreaMB: %u\n",
2204 TCMU_BLOCKS_TO_MBS(udev->max_blocks));
2205
2206 return bl;
2207}
2208
2209static sector_t tcmu_get_blocks(struct se_device *dev)
2210{
2211 struct tcmu_dev *udev = TCMU_DEV(dev);
2212
2213 return div_u64(udev->dev_size - dev->dev_attrib.block_size,
2214 dev->dev_attrib.block_size);
2215}
2216
2217static sense_reason_t
2218tcmu_parse_cdb(struct se_cmd *cmd)
2219{
2220 return passthrough_parse_cdb(cmd, tcmu_queue_cmd);
2221}
2222
2223static ssize_t tcmu_cmd_time_out_show(struct config_item *item, char *page)
2224{
2225 struct se_dev_attrib *da = container_of(to_config_group(item),
2226 struct se_dev_attrib, da_group);
2227 struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
2228
2229 return snprintf(page, PAGE_SIZE, "%lu\n", udev->cmd_time_out / MSEC_PER_SEC);
2230}
2231
2232static ssize_t tcmu_cmd_time_out_store(struct config_item *item, const char *page,
2233 size_t count)
2234{
2235 struct se_dev_attrib *da = container_of(to_config_group(item),
2236 struct se_dev_attrib, da_group);
2237 struct tcmu_dev *udev = container_of(da->da_dev,
2238 struct tcmu_dev, se_dev);
2239 u32 val;
2240 int ret;
2241
2242 if (da->da_dev->export_count) {
2243 pr_err("Unable to set tcmu cmd_time_out while exports exist\n");
2244 return -EINVAL;
2245 }
2246
2247 ret = kstrtou32(page, 0, &val);
2248 if (ret < 0)
2249 return ret;
2250
2251 udev->cmd_time_out = val * MSEC_PER_SEC;
2252 return count;
2253}
2254CONFIGFS_ATTR(tcmu_, cmd_time_out);
2255
2256static ssize_t tcmu_qfull_time_out_show(struct config_item *item, char *page)
2257{
2258 struct se_dev_attrib *da = container_of(to_config_group(item),
2259 struct se_dev_attrib, da_group);
2260 struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
2261
2262 return snprintf(page, PAGE_SIZE, "%ld\n", udev->qfull_time_out <= 0 ?
2263 udev->qfull_time_out :
2264 udev->qfull_time_out / MSEC_PER_SEC);
2265}
2266
2267static ssize_t tcmu_qfull_time_out_store(struct config_item *item,
2268 const char *page, size_t count)
2269{
2270 struct se_dev_attrib *da = container_of(to_config_group(item),
2271 struct se_dev_attrib, da_group);
2272 struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
2273 s32 val;
2274 int ret;
2275
2276 ret = kstrtos32(page, 0, &val);
2277 if (ret < 0)
2278 return ret;
2279
2280 if (val >= 0) {
2281 udev->qfull_time_out = val * MSEC_PER_SEC;
2282 } else if (val == -1) {
2283 udev->qfull_time_out = val;
2284 } else {
2285 printk(KERN_ERR "Invalid qfull timeout value %d\n", val);
2286 return -EINVAL;
2287 }
2288 return count;
2289}
2290CONFIGFS_ATTR(tcmu_, qfull_time_out);
2291
2292static ssize_t tcmu_max_data_area_mb_show(struct config_item *item, char *page)
2293{
2294 struct se_dev_attrib *da = container_of(to_config_group(item),
2295 struct se_dev_attrib, da_group);
2296 struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
2297
2298 return snprintf(page, PAGE_SIZE, "%u\n",
2299 TCMU_BLOCKS_TO_MBS(udev->max_blocks));
2300}
2301CONFIGFS_ATTR_RO(tcmu_, max_data_area_mb);
2302
2303static ssize_t tcmu_dev_config_show(struct config_item *item, char *page)
2304{
2305 struct se_dev_attrib *da = container_of(to_config_group(item),
2306 struct se_dev_attrib, da_group);
2307 struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
2308
2309 return snprintf(page, PAGE_SIZE, "%s\n", udev->dev_config);
2310}
2311
2312static int tcmu_send_dev_config_event(struct tcmu_dev *udev,
2313 const char *reconfig_data)
2314{
2315 struct sk_buff *skb = NULL;
2316 void *msg_header = NULL;
2317 int ret = 0;
2318
2319 ret = tcmu_netlink_event_init(udev, TCMU_CMD_RECONFIG_DEVICE,
2320 &skb, &msg_header);
2321 if (ret < 0)
2322 return ret;
2323 ret = nla_put_string(skb, TCMU_ATTR_DEV_CFG, reconfig_data);
2324 if (ret < 0) {
2325 nlmsg_free(skb);
2326 return ret;
2327 }
2328 return tcmu_netlink_event_send(udev, TCMU_CMD_RECONFIG_DEVICE,
2329 skb, msg_header);
2330}
2331
2332
2333static ssize_t tcmu_dev_config_store(struct config_item *item, const char *page,
2334 size_t count)
2335{
2336 struct se_dev_attrib *da = container_of(to_config_group(item),
2337 struct se_dev_attrib, da_group);
2338 struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
2339 int ret, len;
2340
2341 len = strlen(page);
2342 if (!len || len > TCMU_CONFIG_LEN - 1)
2343 return -EINVAL;
2344
2345
2346 if (target_dev_configured(&udev->se_dev)) {
2347 ret = tcmu_send_dev_config_event(udev, page);
2348 if (ret) {
2349 pr_err("Unable to reconfigure device\n");
2350 return ret;
2351 }
2352 strlcpy(udev->dev_config, page, TCMU_CONFIG_LEN);
2353
2354 ret = tcmu_update_uio_info(udev);
2355 if (ret)
2356 return ret;
2357 return count;
2358 }
2359 strlcpy(udev->dev_config, page, TCMU_CONFIG_LEN);
2360
2361 return count;
2362}
2363CONFIGFS_ATTR(tcmu_, dev_config);
2364
2365static ssize_t tcmu_dev_size_show(struct config_item *item, char *page)
2366{
2367 struct se_dev_attrib *da = container_of(to_config_group(item),
2368 struct se_dev_attrib, da_group);
2369 struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
2370
2371 return snprintf(page, PAGE_SIZE, "%llu\n", udev->dev_size);
2372}
2373
2374static int tcmu_send_dev_size_event(struct tcmu_dev *udev, u64 size)
2375{
2376 struct sk_buff *skb = NULL;
2377 void *msg_header = NULL;
2378 int ret = 0;
2379
2380 ret = tcmu_netlink_event_init(udev, TCMU_CMD_RECONFIG_DEVICE,
2381 &skb, &msg_header);
2382 if (ret < 0)
2383 return ret;
2384 ret = nla_put_u64_64bit(skb, TCMU_ATTR_DEV_SIZE,
2385 size, TCMU_ATTR_PAD);
2386 if (ret < 0) {
2387 nlmsg_free(skb);
2388 return ret;
2389 }
2390 return tcmu_netlink_event_send(udev, TCMU_CMD_RECONFIG_DEVICE,
2391 skb, msg_header);
2392}
2393
2394static ssize_t tcmu_dev_size_store(struct config_item *item, const char *page,
2395 size_t count)
2396{
2397 struct se_dev_attrib *da = container_of(to_config_group(item),
2398 struct se_dev_attrib, da_group);
2399 struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
2400 u64 val;
2401 int ret;
2402
2403 ret = kstrtou64(page, 0, &val);
2404 if (ret < 0)
2405 return ret;
2406
2407
2408 if (target_dev_configured(&udev->se_dev)) {
2409 ret = tcmu_send_dev_size_event(udev, val);
2410 if (ret) {
2411 pr_err("Unable to reconfigure device\n");
2412 return ret;
2413 }
2414 }
2415 udev->dev_size = val;
2416 return count;
2417}
2418CONFIGFS_ATTR(tcmu_, dev_size);
2419
2420static ssize_t tcmu_nl_reply_supported_show(struct config_item *item,
2421 char *page)
2422{
2423 struct se_dev_attrib *da = container_of(to_config_group(item),
2424 struct se_dev_attrib, da_group);
2425 struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
2426
2427 return snprintf(page, PAGE_SIZE, "%d\n", udev->nl_reply_supported);
2428}
2429
2430static ssize_t tcmu_nl_reply_supported_store(struct config_item *item,
2431 const char *page, size_t count)
2432{
2433 struct se_dev_attrib *da = container_of(to_config_group(item),
2434 struct se_dev_attrib, da_group);
2435 struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
2436 s8 val;
2437 int ret;
2438
2439 ret = kstrtos8(page, 0, &val);
2440 if (ret < 0)
2441 return ret;
2442
2443 udev->nl_reply_supported = val;
2444 return count;
2445}
2446CONFIGFS_ATTR(tcmu_, nl_reply_supported);
2447
2448static ssize_t tcmu_emulate_write_cache_show(struct config_item *item,
2449 char *page)
2450{
2451 struct se_dev_attrib *da = container_of(to_config_group(item),
2452 struct se_dev_attrib, da_group);
2453
2454 return snprintf(page, PAGE_SIZE, "%i\n", da->emulate_write_cache);
2455}
2456
2457static int tcmu_send_emulate_write_cache(struct tcmu_dev *udev, u8 val)
2458{
2459 struct sk_buff *skb = NULL;
2460 void *msg_header = NULL;
2461 int ret = 0;
2462
2463 ret = tcmu_netlink_event_init(udev, TCMU_CMD_RECONFIG_DEVICE,
2464 &skb, &msg_header);
2465 if (ret < 0)
2466 return ret;
2467 ret = nla_put_u8(skb, TCMU_ATTR_WRITECACHE, val);
2468 if (ret < 0) {
2469 nlmsg_free(skb);
2470 return ret;
2471 }
2472 return tcmu_netlink_event_send(udev, TCMU_CMD_RECONFIG_DEVICE,
2473 skb, msg_header);
2474}
2475
2476static ssize_t tcmu_emulate_write_cache_store(struct config_item *item,
2477 const char *page, size_t count)
2478{
2479 struct se_dev_attrib *da = container_of(to_config_group(item),
2480 struct se_dev_attrib, da_group);
2481 struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
2482 u8 val;
2483 int ret;
2484
2485 ret = kstrtou8(page, 0, &val);
2486 if (ret < 0)
2487 return ret;
2488
2489
2490 if (target_dev_configured(&udev->se_dev)) {
2491 ret = tcmu_send_emulate_write_cache(udev, val);
2492 if (ret) {
2493 pr_err("Unable to reconfigure device\n");
2494 return ret;
2495 }
2496 }
2497
2498 da->emulate_write_cache = val;
2499 return count;
2500}
2501CONFIGFS_ATTR(tcmu_, emulate_write_cache);
2502
2503static ssize_t tcmu_block_dev_show(struct config_item *item, char *page)
2504{
2505 struct se_device *se_dev = container_of(to_config_group(item),
2506 struct se_device,
2507 dev_action_group);
2508 struct tcmu_dev *udev = TCMU_DEV(se_dev);
2509
2510 if (test_bit(TCMU_DEV_BIT_BLOCKED, &udev->flags))
2511 return snprintf(page, PAGE_SIZE, "%s\n", "blocked");
2512 else
2513 return snprintf(page, PAGE_SIZE, "%s\n", "unblocked");
2514}
2515
2516static ssize_t tcmu_block_dev_store(struct config_item *item, const char *page,
2517 size_t count)
2518{
2519 struct se_device *se_dev = container_of(to_config_group(item),
2520 struct se_device,
2521 dev_action_group);
2522 struct tcmu_dev *udev = TCMU_DEV(se_dev);
2523 u8 val;
2524 int ret;
2525
2526 if (!target_dev_configured(&udev->se_dev)) {
2527 pr_err("Device is not configured.\n");
2528 return -EINVAL;
2529 }
2530
2531 ret = kstrtou8(page, 0, &val);
2532 if (ret < 0)
2533 return ret;
2534
2535 if (val > 1) {
2536 pr_err("Invalid block value %d\n", val);
2537 return -EINVAL;
2538 }
2539
2540 if (!val)
2541 tcmu_unblock_dev(udev);
2542 else
2543 tcmu_block_dev(udev);
2544 return count;
2545}
2546CONFIGFS_ATTR(tcmu_, block_dev);
2547
2548static ssize_t tcmu_reset_ring_store(struct config_item *item, const char *page,
2549 size_t count)
2550{
2551 struct se_device *se_dev = container_of(to_config_group(item),
2552 struct se_device,
2553 dev_action_group);
2554 struct tcmu_dev *udev = TCMU_DEV(se_dev);
2555 u8 val;
2556 int ret;
2557
2558 if (!target_dev_configured(&udev->se_dev)) {
2559 pr_err("Device is not configured.\n");
2560 return -EINVAL;
2561 }
2562
2563 ret = kstrtou8(page, 0, &val);
2564 if (ret < 0)
2565 return ret;
2566
2567 if (val != 1 && val != 2) {
2568 pr_err("Invalid reset ring value %d\n", val);
2569 return -EINVAL;
2570 }
2571
2572 tcmu_reset_ring(udev, val);
2573 return count;
2574}
2575CONFIGFS_ATTR_WO(tcmu_, reset_ring);
2576
2577static struct configfs_attribute *tcmu_attrib_attrs[] = {
2578 &tcmu_attr_cmd_time_out,
2579 &tcmu_attr_qfull_time_out,
2580 &tcmu_attr_max_data_area_mb,
2581 &tcmu_attr_dev_config,
2582 &tcmu_attr_dev_size,
2583 &tcmu_attr_emulate_write_cache,
2584 &tcmu_attr_nl_reply_supported,
2585 NULL,
2586};
2587
2588static struct configfs_attribute **tcmu_attrs;
2589
2590static struct configfs_attribute *tcmu_action_attrs[] = {
2591 &tcmu_attr_block_dev,
2592 &tcmu_attr_reset_ring,
2593 NULL,
2594};
2595
2596static struct target_backend_ops tcmu_ops = {
2597 .name = "user",
2598 .owner = THIS_MODULE,
2599 .transport_flags = TRANSPORT_FLAG_PASSTHROUGH,
2600 .attach_hba = tcmu_attach_hba,
2601 .detach_hba = tcmu_detach_hba,
2602 .alloc_device = tcmu_alloc_device,
2603 .configure_device = tcmu_configure_device,
2604 .destroy_device = tcmu_destroy_device,
2605 .free_device = tcmu_free_device,
2606 .parse_cdb = tcmu_parse_cdb,
2607 .set_configfs_dev_params = tcmu_set_configfs_dev_params,
2608 .show_configfs_dev_params = tcmu_show_configfs_dev_params,
2609 .get_device_type = sbc_get_device_type,
2610 .get_blocks = tcmu_get_blocks,
2611 .tb_dev_action_attrs = tcmu_action_attrs,
2612};
2613
2614static void find_free_blocks(void)
2615{
2616 struct tcmu_dev *udev;
2617 loff_t off;
2618 u32 start, end, block, total_freed = 0;
2619
2620 if (atomic_read(&global_db_count) <= tcmu_global_max_blocks)
2621 return;
2622
2623 mutex_lock(&root_udev_mutex);
2624 list_for_each_entry(udev, &root_udev, node) {
2625 mutex_lock(&udev->cmdr_lock);
2626
2627 if (!target_dev_configured(&udev->se_dev)) {
2628 mutex_unlock(&udev->cmdr_lock);
2629 continue;
2630 }
2631
2632
2633 tcmu_handle_completions(udev);
2634
2635
2636 if (!udev->dbi_thresh) {
2637 mutex_unlock(&udev->cmdr_lock);
2638 continue;
2639 }
2640
2641 end = udev->dbi_max + 1;
2642 block = find_last_bit(udev->data_bitmap, end);
2643 if (block == udev->dbi_max) {
2644
2645
2646
2647
2648 mutex_unlock(&udev->cmdr_lock);
2649 continue;
2650 } else if (block == end) {
2651
2652 udev->dbi_thresh = start = 0;
2653 udev->dbi_max = 0;
2654 } else {
2655 udev->dbi_thresh = start = block + 1;
2656 udev->dbi_max = block;
2657 }
2658
2659
2660 off = udev->data_off + start * DATA_BLOCK_SIZE;
2661 unmap_mapping_range(udev->inode->i_mapping, off, 0, 1);
2662
2663
2664 tcmu_blocks_release(&udev->data_blocks, start, end);
2665 mutex_unlock(&udev->cmdr_lock);
2666
2667 total_freed += end - start;
2668 pr_debug("Freed %u blocks (total %u) from %s.\n", end - start,
2669 total_freed, udev->name);
2670 }
2671 mutex_unlock(&root_udev_mutex);
2672
2673 if (atomic_read(&global_db_count) > tcmu_global_max_blocks)
2674 schedule_delayed_work(&tcmu_unmap_work, msecs_to_jiffies(5000));
2675}
2676
2677static void check_timedout_devices(void)
2678{
2679 struct tcmu_dev *udev, *tmp_dev;
2680 LIST_HEAD(devs);
2681
2682 spin_lock_bh(&timed_out_udevs_lock);
2683 list_splice_init(&timed_out_udevs, &devs);
2684
2685 list_for_each_entry_safe(udev, tmp_dev, &devs, timedout_entry) {
2686 list_del_init(&udev->timedout_entry);
2687 spin_unlock_bh(&timed_out_udevs_lock);
2688
2689 mutex_lock(&udev->cmdr_lock);
2690 idr_for_each(&udev->commands, tcmu_check_expired_cmd, NULL);
2691
2692 tcmu_set_next_deadline(&udev->inflight_queue, &udev->cmd_timer);
2693 tcmu_set_next_deadline(&udev->qfull_queue, &udev->qfull_timer);
2694
2695 mutex_unlock(&udev->cmdr_lock);
2696
2697 spin_lock_bh(&timed_out_udevs_lock);
2698 }
2699
2700 spin_unlock_bh(&timed_out_udevs_lock);
2701}
2702
2703static void tcmu_unmap_work_fn(struct work_struct *work)
2704{
2705 check_timedout_devices();
2706 find_free_blocks();
2707}
2708
2709static int __init tcmu_module_init(void)
2710{
2711 int ret, i, k, len = 0;
2712
2713 BUILD_BUG_ON((sizeof(struct tcmu_cmd_entry) % TCMU_OP_ALIGN_SIZE) != 0);
2714
2715 INIT_DELAYED_WORK(&tcmu_unmap_work, tcmu_unmap_work_fn);
2716
2717 tcmu_cmd_cache = kmem_cache_create("tcmu_cmd_cache",
2718 sizeof(struct tcmu_cmd),
2719 __alignof__(struct tcmu_cmd),
2720 0, NULL);
2721 if (!tcmu_cmd_cache)
2722 return -ENOMEM;
2723
2724 tcmu_root_device = root_device_register("tcm_user");
2725 if (IS_ERR(tcmu_root_device)) {
2726 ret = PTR_ERR(tcmu_root_device);
2727 goto out_free_cache;
2728 }
2729
2730 ret = genl_register_family(&tcmu_genl_family);
2731 if (ret < 0) {
2732 goto out_unreg_device;
2733 }
2734
2735 for (i = 0; passthrough_attrib_attrs[i] != NULL; i++) {
2736 len += sizeof(struct configfs_attribute *);
2737 }
2738 for (i = 0; tcmu_attrib_attrs[i] != NULL; i++) {
2739 len += sizeof(struct configfs_attribute *);
2740 }
2741 len += sizeof(struct configfs_attribute *);
2742
2743 tcmu_attrs = kzalloc(len, GFP_KERNEL);
2744 if (!tcmu_attrs) {
2745 ret = -ENOMEM;
2746 goto out_unreg_genl;
2747 }
2748
2749 for (i = 0; passthrough_attrib_attrs[i] != NULL; i++) {
2750 tcmu_attrs[i] = passthrough_attrib_attrs[i];
2751 }
2752 for (k = 0; tcmu_attrib_attrs[k] != NULL; k++) {
2753 tcmu_attrs[i] = tcmu_attrib_attrs[k];
2754 i++;
2755 }
2756 tcmu_ops.tb_dev_attrib_attrs = tcmu_attrs;
2757
2758 ret = transport_backend_register(&tcmu_ops);
2759 if (ret)
2760 goto out_attrs;
2761
2762 return 0;
2763
2764out_attrs:
2765 kfree(tcmu_attrs);
2766out_unreg_genl:
2767 genl_unregister_family(&tcmu_genl_family);
2768out_unreg_device:
2769 root_device_unregister(tcmu_root_device);
2770out_free_cache:
2771 kmem_cache_destroy(tcmu_cmd_cache);
2772
2773 return ret;
2774}
2775
2776static void __exit tcmu_module_exit(void)
2777{
2778 cancel_delayed_work_sync(&tcmu_unmap_work);
2779 target_backend_unregister(&tcmu_ops);
2780 kfree(tcmu_attrs);
2781 genl_unregister_family(&tcmu_genl_family);
2782 root_device_unregister(tcmu_root_device);
2783 kmem_cache_destroy(tcmu_cmd_cache);
2784}
2785
2786MODULE_DESCRIPTION("TCM USER subsystem plugin");
2787MODULE_AUTHOR("Shaohua Li <shli@kernel.org>");
2788MODULE_AUTHOR("Andy Grover <agrover@redhat.com>");
2789MODULE_LICENSE("GPL");
2790
2791module_init(tcmu_module_init);
2792module_exit(tcmu_module_exit);
2793