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7c9e7a6f AG |
1 | /* |
2 | * Copyright (C) 2013 Shaohua Li <shli@kernel.org> | |
3 | * Copyright (C) 2014 Red Hat, Inc. | |
f97ec7db | 4 | * Copyright (C) 2015 Arrikto, Inc. |
7c9e7a6f AG |
5 | * |
6 | * This program is free software; you can redistribute it and/or modify it | |
7 | * under the terms and conditions of the GNU General Public License, | |
8 | * version 2, as published by the Free Software Foundation. | |
9 | * | |
10 | * This program is distributed in the hope it will be useful, but WITHOUT | |
11 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
12 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
13 | * more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License along with | |
16 | * this program; if not, write to the Free Software Foundation, Inc., | |
17 | * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. | |
18 | */ | |
19 | ||
20 | #include <linux/spinlock.h> | |
21 | #include <linux/module.h> | |
22 | #include <linux/idr.h> | |
ba929992 | 23 | #include <linux/kernel.h> |
7c9e7a6f AG |
24 | #include <linux/timer.h> |
25 | #include <linux/parser.h> | |
5538d294 | 26 | #include <linux/vmalloc.h> |
7c9e7a6f | 27 | #include <linux/uio_driver.h> |
ac64a2ce | 28 | #include <linux/stringify.h> |
7c9e7a6f | 29 | #include <net/genetlink.h> |
ba929992 BVA |
30 | #include <scsi/scsi_common.h> |
31 | #include <scsi/scsi_proto.h> | |
7c9e7a6f AG |
32 | #include <target/target_core_base.h> |
33 | #include <target/target_core_fabric.h> | |
34 | #include <target/target_core_backend.h> | |
e9f720d6 | 35 | |
7c9e7a6f AG |
36 | #include <linux/target_core_user.h> |
37 | ||
38 | /* | |
39 | * Define a shared-memory interface for LIO to pass SCSI commands and | |
40 | * data to userspace for processing. This is to allow backends that | |
41 | * are too complex for in-kernel support to be possible. | |
42 | * | |
43 | * It uses the UIO framework to do a lot of the device-creation and | |
44 | * introspection work for us. | |
45 | * | |
46 | * See the .h file for how the ring is laid out. Note that while the | |
47 | * command ring is defined, the particulars of the data area are | |
48 | * not. Offset values in the command entry point to other locations | |
49 | * internal to the mmap()ed area. There is separate space outside the | |
50 | * command ring for data buffers. This leaves maximum flexibility for | |
51 | * moving buffer allocations, or even page flipping or other | |
52 | * allocation techniques, without altering the command ring layout. | |
53 | * | |
54 | * SECURITY: | |
55 | * The user process must be assumed to be malicious. There's no way to | |
56 | * prevent it breaking the command ring protocol if it wants, but in | |
57 | * order to prevent other issues we must only ever read *data* from | |
58 | * the shared memory area, not offsets or sizes. This applies to | |
59 | * command ring entries as well as the mailbox. Extra code needed for | |
60 | * this may have a 'UAM' comment. | |
61 | */ | |
62 | ||
63 | ||
64 | #define TCMU_TIME_OUT (30 * MSEC_PER_SEC) | |
65 | ||
66 | #define CMDR_SIZE (16 * 4096) | |
67 | #define DATA_SIZE (257 * 4096) | |
68 | ||
69 | #define TCMU_RING_SIZE (CMDR_SIZE + DATA_SIZE) | |
70 | ||
71 | static struct device *tcmu_root_device; | |
72 | ||
73 | struct tcmu_hba { | |
74 | u32 host_id; | |
75 | }; | |
76 | ||
7c9e7a6f AG |
77 | #define TCMU_CONFIG_LEN 256 |
78 | ||
79 | struct tcmu_dev { | |
80 | struct se_device se_dev; | |
81 | ||
82 | char *name; | |
83 | struct se_hba *hba; | |
84 | ||
85 | #define TCMU_DEV_BIT_OPEN 0 | |
86 | #define TCMU_DEV_BIT_BROKEN 1 | |
87 | unsigned long flags; | |
7c9e7a6f AG |
88 | |
89 | struct uio_info uio_info; | |
90 | ||
91 | struct tcmu_mailbox *mb_addr; | |
92 | size_t dev_size; | |
93 | u32 cmdr_size; | |
94 | u32 cmdr_last_cleaned; | |
95 | /* Offset of data ring from start of mb */ | |
96 | size_t data_off; | |
97 | size_t data_size; | |
98 | /* Ring head + tail values. */ | |
99 | /* Must add data_off and mb_addr to get the address */ | |
100 | size_t data_head; | |
101 | size_t data_tail; | |
102 | ||
103 | wait_queue_head_t wait_cmdr; | |
104 | /* TODO should this be a mutex? */ | |
105 | spinlock_t cmdr_lock; | |
106 | ||
107 | struct idr commands; | |
108 | spinlock_t commands_lock; | |
109 | ||
110 | struct timer_list timeout; | |
111 | ||
112 | char dev_config[TCMU_CONFIG_LEN]; | |
113 | }; | |
114 | ||
115 | #define TCMU_DEV(_se_dev) container_of(_se_dev, struct tcmu_dev, se_dev) | |
116 | ||
117 | #define CMDR_OFF sizeof(struct tcmu_mailbox) | |
118 | ||
119 | struct tcmu_cmd { | |
120 | struct se_cmd *se_cmd; | |
121 | struct tcmu_dev *tcmu_dev; | |
122 | ||
123 | uint16_t cmd_id; | |
124 | ||
125 | /* Can't use se_cmd->data_length when cleaning up expired cmds, because if | |
126 | cmd has been completed then accessing se_cmd is off limits */ | |
127 | size_t data_length; | |
128 | ||
129 | unsigned long deadline; | |
130 | ||
131 | #define TCMU_CMD_BIT_EXPIRED 0 | |
132 | unsigned long flags; | |
133 | }; | |
134 | ||
135 | static struct kmem_cache *tcmu_cmd_cache; | |
136 | ||
137 | /* multicast group */ | |
138 | enum tcmu_multicast_groups { | |
139 | TCMU_MCGRP_CONFIG, | |
140 | }; | |
141 | ||
142 | static const struct genl_multicast_group tcmu_mcgrps[] = { | |
143 | [TCMU_MCGRP_CONFIG] = { .name = "config", }, | |
144 | }; | |
145 | ||
146 | /* Our generic netlink family */ | |
147 | static struct genl_family tcmu_genl_family = { | |
148 | .id = GENL_ID_GENERATE, | |
149 | .hdrsize = 0, | |
150 | .name = "TCM-USER", | |
151 | .version = 1, | |
152 | .maxattr = TCMU_ATTR_MAX, | |
153 | .mcgrps = tcmu_mcgrps, | |
154 | .n_mcgrps = ARRAY_SIZE(tcmu_mcgrps), | |
20c08b36 | 155 | .netnsok = true, |
7c9e7a6f AG |
156 | }; |
157 | ||
158 | static struct tcmu_cmd *tcmu_alloc_cmd(struct se_cmd *se_cmd) | |
159 | { | |
160 | struct se_device *se_dev = se_cmd->se_dev; | |
161 | struct tcmu_dev *udev = TCMU_DEV(se_dev); | |
162 | struct tcmu_cmd *tcmu_cmd; | |
163 | int cmd_id; | |
164 | ||
165 | tcmu_cmd = kmem_cache_zalloc(tcmu_cmd_cache, GFP_KERNEL); | |
166 | if (!tcmu_cmd) | |
167 | return NULL; | |
168 | ||
169 | tcmu_cmd->se_cmd = se_cmd; | |
170 | tcmu_cmd->tcmu_dev = udev; | |
171 | tcmu_cmd->data_length = se_cmd->data_length; | |
172 | ||
e4648b01 IT |
173 | if (se_cmd->se_cmd_flags & SCF_BIDI) { |
174 | BUG_ON(!(se_cmd->t_bidi_data_sg && se_cmd->t_bidi_data_nents)); | |
175 | tcmu_cmd->data_length += se_cmd->t_bidi_data_sg->length; | |
176 | } | |
177 | ||
7c9e7a6f AG |
178 | tcmu_cmd->deadline = jiffies + msecs_to_jiffies(TCMU_TIME_OUT); |
179 | ||
180 | idr_preload(GFP_KERNEL); | |
181 | spin_lock_irq(&udev->commands_lock); | |
182 | cmd_id = idr_alloc(&udev->commands, tcmu_cmd, 0, | |
183 | USHRT_MAX, GFP_NOWAIT); | |
184 | spin_unlock_irq(&udev->commands_lock); | |
185 | idr_preload_end(); | |
186 | ||
187 | if (cmd_id < 0) { | |
188 | kmem_cache_free(tcmu_cmd_cache, tcmu_cmd); | |
189 | return NULL; | |
190 | } | |
191 | tcmu_cmd->cmd_id = cmd_id; | |
192 | ||
193 | return tcmu_cmd; | |
194 | } | |
195 | ||
196 | static inline void tcmu_flush_dcache_range(void *vaddr, size_t size) | |
197 | { | |
b75d8063 | 198 | unsigned long offset = offset_in_page(vaddr); |
7c9e7a6f AG |
199 | |
200 | size = round_up(size+offset, PAGE_SIZE); | |
201 | vaddr -= offset; | |
202 | ||
203 | while (size) { | |
204 | flush_dcache_page(virt_to_page(vaddr)); | |
205 | size -= PAGE_SIZE; | |
206 | } | |
207 | } | |
208 | ||
209 | /* | |
210 | * Some ring helper functions. We don't assume size is a power of 2 so | |
211 | * we can't use circ_buf.h. | |
212 | */ | |
213 | static inline size_t spc_used(size_t head, size_t tail, size_t size) | |
214 | { | |
215 | int diff = head - tail; | |
216 | ||
217 | if (diff >= 0) | |
218 | return diff; | |
219 | else | |
220 | return size + diff; | |
221 | } | |
222 | ||
223 | static inline size_t spc_free(size_t head, size_t tail, size_t size) | |
224 | { | |
225 | /* Keep 1 byte unused or we can't tell full from empty */ | |
226 | return (size - spc_used(head, tail, size) - 1); | |
227 | } | |
228 | ||
229 | static inline size_t head_to_end(size_t head, size_t size) | |
230 | { | |
231 | return size - head; | |
232 | } | |
233 | ||
234 | #define UPDATE_HEAD(head, used, size) smp_store_release(&head, ((head % size) + used) % size) | |
235 | ||
f97ec7db IT |
236 | static void alloc_and_scatter_data_area(struct tcmu_dev *udev, |
237 | struct scatterlist *data_sg, unsigned int data_nents, | |
238 | struct iovec **iov, int *iov_cnt, bool copy_data) | |
239 | { | |
240 | int i; | |
241 | void *from, *to; | |
242 | size_t copy_bytes; | |
243 | struct scatterlist *sg; | |
244 | ||
245 | for_each_sg(data_sg, sg, data_nents, i) { | |
246 | copy_bytes = min_t(size_t, sg->length, | |
247 | head_to_end(udev->data_head, udev->data_size)); | |
248 | from = kmap_atomic(sg_page(sg)) + sg->offset; | |
249 | to = (void *) udev->mb_addr + udev->data_off + udev->data_head; | |
250 | ||
251 | if (copy_data) { | |
252 | memcpy(to, from, copy_bytes); | |
253 | tcmu_flush_dcache_range(to, copy_bytes); | |
254 | } | |
255 | ||
256 | /* Even iov_base is relative to mb_addr */ | |
257 | (*iov)->iov_len = copy_bytes; | |
258 | (*iov)->iov_base = (void __user *) udev->data_off + | |
259 | udev->data_head; | |
260 | (*iov_cnt)++; | |
261 | (*iov)++; | |
262 | ||
263 | UPDATE_HEAD(udev->data_head, copy_bytes, udev->data_size); | |
264 | ||
265 | /* Uh oh, we wrapped the buffer. Must split sg across 2 iovs. */ | |
266 | if (sg->length != copy_bytes) { | |
e2e21bd8 SG |
267 | void *from_skip = from + copy_bytes; |
268 | ||
f97ec7db IT |
269 | copy_bytes = sg->length - copy_bytes; |
270 | ||
271 | (*iov)->iov_len = copy_bytes; | |
272 | (*iov)->iov_base = (void __user *) udev->data_off + | |
273 | udev->data_head; | |
274 | ||
275 | if (copy_data) { | |
276 | to = (void *) udev->mb_addr + | |
277 | udev->data_off + udev->data_head; | |
e2e21bd8 | 278 | memcpy(to, from_skip, copy_bytes); |
f97ec7db IT |
279 | tcmu_flush_dcache_range(to, copy_bytes); |
280 | } | |
281 | ||
282 | (*iov_cnt)++; | |
283 | (*iov)++; | |
284 | ||
285 | UPDATE_HEAD(udev->data_head, | |
286 | copy_bytes, udev->data_size); | |
287 | } | |
288 | ||
e2e21bd8 | 289 | kunmap_atomic(from - sg->offset); |
f97ec7db IT |
290 | } |
291 | } | |
292 | ||
293 | static void gather_and_free_data_area(struct tcmu_dev *udev, | |
294 | struct scatterlist *data_sg, unsigned int data_nents) | |
295 | { | |
296 | int i; | |
297 | void *from, *to; | |
298 | size_t copy_bytes; | |
299 | struct scatterlist *sg; | |
300 | ||
301 | /* It'd be easier to look at entry's iovec again, but UAM */ | |
302 | for_each_sg(data_sg, sg, data_nents, i) { | |
303 | copy_bytes = min_t(size_t, sg->length, | |
304 | head_to_end(udev->data_tail, udev->data_size)); | |
305 | ||
306 | to = kmap_atomic(sg_page(sg)) + sg->offset; | |
307 | WARN_ON(sg->length + sg->offset > PAGE_SIZE); | |
308 | from = (void *) udev->mb_addr + | |
309 | udev->data_off + udev->data_tail; | |
310 | tcmu_flush_dcache_range(from, copy_bytes); | |
311 | memcpy(to, from, copy_bytes); | |
312 | ||
313 | UPDATE_HEAD(udev->data_tail, copy_bytes, udev->data_size); | |
314 | ||
315 | /* Uh oh, wrapped the data buffer for this sg's data */ | |
316 | if (sg->length != copy_bytes) { | |
e2e21bd8 SG |
317 | void *to_skip = to + copy_bytes; |
318 | ||
f97ec7db IT |
319 | from = (void *) udev->mb_addr + |
320 | udev->data_off + udev->data_tail; | |
321 | WARN_ON(udev->data_tail); | |
f97ec7db IT |
322 | copy_bytes = sg->length - copy_bytes; |
323 | tcmu_flush_dcache_range(from, copy_bytes); | |
e2e21bd8 | 324 | memcpy(to_skip, from, copy_bytes); |
f97ec7db IT |
325 | |
326 | UPDATE_HEAD(udev->data_tail, | |
327 | copy_bytes, udev->data_size); | |
328 | } | |
e2e21bd8 | 329 | kunmap_atomic(to - sg->offset); |
f97ec7db IT |
330 | } |
331 | } | |
332 | ||
7c9e7a6f | 333 | /* |
f97ec7db IT |
334 | * We can't queue a command until we have space available on the cmd ring *and* |
335 | * space available on the data ring. | |
7c9e7a6f AG |
336 | * |
337 | * Called with ring lock held. | |
338 | */ | |
f56574a2 | 339 | static bool is_ring_space_avail(struct tcmu_dev *udev, size_t cmd_size, size_t data_needed) |
7c9e7a6f AG |
340 | { |
341 | struct tcmu_mailbox *mb = udev->mb_addr; | |
342 | size_t space; | |
343 | u32 cmd_head; | |
f56574a2 | 344 | size_t cmd_needed; |
7c9e7a6f AG |
345 | |
346 | tcmu_flush_dcache_range(mb, sizeof(*mb)); | |
347 | ||
348 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
349 | ||
f56574a2 AG |
350 | /* |
351 | * If cmd end-of-ring space is too small then we need space for a NOP plus | |
352 | * original cmd - cmds are internally contiguous. | |
353 | */ | |
354 | if (head_to_end(cmd_head, udev->cmdr_size) >= cmd_size) | |
355 | cmd_needed = cmd_size; | |
356 | else | |
357 | cmd_needed = cmd_size + head_to_end(cmd_head, udev->cmdr_size); | |
358 | ||
7c9e7a6f AG |
359 | space = spc_free(cmd_head, udev->cmdr_last_cleaned, udev->cmdr_size); |
360 | if (space < cmd_needed) { | |
361 | pr_debug("no cmd space: %u %u %u\n", cmd_head, | |
362 | udev->cmdr_last_cleaned, udev->cmdr_size); | |
363 | return false; | |
364 | } | |
365 | ||
366 | space = spc_free(udev->data_head, udev->data_tail, udev->data_size); | |
367 | if (space < data_needed) { | |
368 | pr_debug("no data space: %zu %zu %zu\n", udev->data_head, | |
369 | udev->data_tail, udev->data_size); | |
370 | return false; | |
371 | } | |
372 | ||
373 | return true; | |
374 | } | |
375 | ||
376 | static int tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd) | |
377 | { | |
378 | struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; | |
379 | struct se_cmd *se_cmd = tcmu_cmd->se_cmd; | |
380 | size_t base_command_size, command_size; | |
7c9e7a6f | 381 | struct tcmu_mailbox *mb; |
7c9e7a6f | 382 | struct tcmu_cmd_entry *entry; |
7c9e7a6f | 383 | struct iovec *iov; |
f97ec7db | 384 | int iov_cnt; |
7c9e7a6f AG |
385 | uint32_t cmd_head; |
386 | uint64_t cdb_off; | |
f97ec7db | 387 | bool copy_to_data_area; |
7c9e7a6f AG |
388 | |
389 | if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) | |
390 | return -EINVAL; | |
391 | ||
392 | /* | |
393 | * Must be a certain minimum size for response sense info, but | |
394 | * also may be larger if the iov array is large. | |
395 | * | |
396 | * iovs = sgl_nents+1, for end-of-ring case, plus another 1 | |
397 | * b/c size == offsetof one-past-element. | |
398 | */ | |
399 | base_command_size = max(offsetof(struct tcmu_cmd_entry, | |
e4648b01 IT |
400 | req.iov[se_cmd->t_bidi_data_nents + |
401 | se_cmd->t_data_nents + 2]), | |
7c9e7a6f AG |
402 | sizeof(struct tcmu_cmd_entry)); |
403 | command_size = base_command_size | |
404 | + round_up(scsi_command_size(se_cmd->t_task_cdb), TCMU_OP_ALIGN_SIZE); | |
405 | ||
406 | WARN_ON(command_size & (TCMU_OP_ALIGN_SIZE-1)); | |
407 | ||
408 | spin_lock_irq(&udev->cmdr_lock); | |
409 | ||
410 | mb = udev->mb_addr; | |
411 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
412 | if ((command_size > (udev->cmdr_size / 2)) | |
413 | || tcmu_cmd->data_length > (udev->data_size - 1)) | |
414 | pr_warn("TCMU: Request of size %zu/%zu may be too big for %u/%zu " | |
415 | "cmd/data ring buffers\n", command_size, tcmu_cmd->data_length, | |
416 | udev->cmdr_size, udev->data_size); | |
417 | ||
f56574a2 | 418 | while (!is_ring_space_avail(udev, command_size, tcmu_cmd->data_length)) { |
7c9e7a6f AG |
419 | int ret; |
420 | DEFINE_WAIT(__wait); | |
421 | ||
422 | prepare_to_wait(&udev->wait_cmdr, &__wait, TASK_INTERRUPTIBLE); | |
423 | ||
424 | pr_debug("sleeping for ring space\n"); | |
425 | spin_unlock_irq(&udev->cmdr_lock); | |
426 | ret = schedule_timeout(msecs_to_jiffies(TCMU_TIME_OUT)); | |
427 | finish_wait(&udev->wait_cmdr, &__wait); | |
428 | if (!ret) { | |
429 | pr_warn("tcmu: command timed out\n"); | |
430 | return -ETIMEDOUT; | |
431 | } | |
432 | ||
433 | spin_lock_irq(&udev->cmdr_lock); | |
434 | ||
435 | /* We dropped cmdr_lock, cmd_head is stale */ | |
436 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
437 | } | |
438 | ||
f56574a2 AG |
439 | /* Insert a PAD if end-of-ring space is too small */ |
440 | if (head_to_end(cmd_head, udev->cmdr_size) < command_size) { | |
441 | size_t pad_size = head_to_end(cmd_head, udev->cmdr_size); | |
442 | ||
7c9e7a6f AG |
443 | entry = (void *) mb + CMDR_OFF + cmd_head; |
444 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
0ad46af8 AG |
445 | tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_PAD); |
446 | tcmu_hdr_set_len(&entry->hdr.len_op, pad_size); | |
447 | entry->hdr.cmd_id = 0; /* not used for PAD */ | |
448 | entry->hdr.kflags = 0; | |
449 | entry->hdr.uflags = 0; | |
7c9e7a6f AG |
450 | |
451 | UPDATE_HEAD(mb->cmd_head, pad_size, udev->cmdr_size); | |
452 | ||
453 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
454 | WARN_ON(cmd_head != 0); | |
455 | } | |
456 | ||
457 | entry = (void *) mb + CMDR_OFF + cmd_head; | |
458 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
0ad46af8 AG |
459 | tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_CMD); |
460 | tcmu_hdr_set_len(&entry->hdr.len_op, command_size); | |
461 | entry->hdr.cmd_id = tcmu_cmd->cmd_id; | |
462 | entry->hdr.kflags = 0; | |
463 | entry->hdr.uflags = 0; | |
7c9e7a6f AG |
464 | |
465 | /* | |
466 | * Fix up iovecs, and handle if allocation in data ring wrapped. | |
467 | */ | |
468 | iov = &entry->req.iov[0]; | |
f97ec7db | 469 | iov_cnt = 0; |
e4648b01 IT |
470 | copy_to_data_area = (se_cmd->data_direction == DMA_TO_DEVICE |
471 | || se_cmd->se_cmd_flags & SCF_BIDI); | |
f97ec7db IT |
472 | alloc_and_scatter_data_area(udev, se_cmd->t_data_sg, |
473 | se_cmd->t_data_nents, &iov, &iov_cnt, copy_to_data_area); | |
7c9e7a6f | 474 | entry->req.iov_cnt = iov_cnt; |
0ad46af8 | 475 | entry->req.iov_dif_cnt = 0; |
7c9e7a6f | 476 | |
e4648b01 IT |
477 | /* Handle BIDI commands */ |
478 | iov_cnt = 0; | |
479 | alloc_and_scatter_data_area(udev, se_cmd->t_bidi_data_sg, | |
480 | se_cmd->t_bidi_data_nents, &iov, &iov_cnt, false); | |
481 | entry->req.iov_bidi_cnt = iov_cnt; | |
482 | ||
7c9e7a6f AG |
483 | /* All offsets relative to mb_addr, not start of entry! */ |
484 | cdb_off = CMDR_OFF + cmd_head + base_command_size; | |
485 | memcpy((void *) mb + cdb_off, se_cmd->t_task_cdb, scsi_command_size(se_cmd->t_task_cdb)); | |
486 | entry->req.cdb_off = cdb_off; | |
487 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
488 | ||
489 | UPDATE_HEAD(mb->cmd_head, command_size, udev->cmdr_size); | |
490 | tcmu_flush_dcache_range(mb, sizeof(*mb)); | |
491 | ||
492 | spin_unlock_irq(&udev->cmdr_lock); | |
493 | ||
494 | /* TODO: only if FLUSH and FUA? */ | |
495 | uio_event_notify(&udev->uio_info); | |
496 | ||
497 | mod_timer(&udev->timeout, | |
498 | round_jiffies_up(jiffies + msecs_to_jiffies(TCMU_TIME_OUT))); | |
499 | ||
500 | return 0; | |
501 | } | |
502 | ||
503 | static int tcmu_queue_cmd(struct se_cmd *se_cmd) | |
504 | { | |
505 | struct se_device *se_dev = se_cmd->se_dev; | |
506 | struct tcmu_dev *udev = TCMU_DEV(se_dev); | |
507 | struct tcmu_cmd *tcmu_cmd; | |
508 | int ret; | |
509 | ||
510 | tcmu_cmd = tcmu_alloc_cmd(se_cmd); | |
511 | if (!tcmu_cmd) | |
512 | return -ENOMEM; | |
513 | ||
514 | ret = tcmu_queue_cmd_ring(tcmu_cmd); | |
515 | if (ret < 0) { | |
516 | pr_err("TCMU: Could not queue command\n"); | |
517 | spin_lock_irq(&udev->commands_lock); | |
518 | idr_remove(&udev->commands, tcmu_cmd->cmd_id); | |
519 | spin_unlock_irq(&udev->commands_lock); | |
520 | ||
521 | kmem_cache_free(tcmu_cmd_cache, tcmu_cmd); | |
522 | } | |
523 | ||
524 | return ret; | |
525 | } | |
526 | ||
527 | static void tcmu_handle_completion(struct tcmu_cmd *cmd, struct tcmu_cmd_entry *entry) | |
528 | { | |
529 | struct se_cmd *se_cmd = cmd->se_cmd; | |
530 | struct tcmu_dev *udev = cmd->tcmu_dev; | |
531 | ||
532 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) { | |
533 | /* cmd has been completed already from timeout, just reclaim data | |
534 | ring space */ | |
535 | UPDATE_HEAD(udev->data_tail, cmd->data_length, udev->data_size); | |
536 | return; | |
537 | } | |
538 | ||
0ad46af8 AG |
539 | if (entry->hdr.uflags & TCMU_UFLAG_UNKNOWN_OP) { |
540 | UPDATE_HEAD(udev->data_tail, cmd->data_length, udev->data_size); | |
541 | pr_warn("TCMU: Userspace set UNKNOWN_OP flag on se_cmd %p\n", | |
542 | cmd->se_cmd); | |
ed97d0cd AG |
543 | entry->rsp.scsi_status = SAM_STAT_CHECK_CONDITION; |
544 | } else if (entry->rsp.scsi_status == SAM_STAT_CHECK_CONDITION) { | |
7c9e7a6f AG |
545 | memcpy(se_cmd->sense_buffer, entry->rsp.sense_buffer, |
546 | se_cmd->scsi_sense_length); | |
547 | ||
548 | UPDATE_HEAD(udev->data_tail, cmd->data_length, udev->data_size); | |
e4648b01 IT |
549 | } else if (se_cmd->se_cmd_flags & SCF_BIDI) { |
550 | /* Discard data_out buffer */ | |
551 | UPDATE_HEAD(udev->data_tail, | |
552 | (size_t)se_cmd->t_data_sg->length, udev->data_size); | |
553 | ||
554 | /* Get Data-In buffer */ | |
555 | gather_and_free_data_area(udev, | |
556 | se_cmd->t_bidi_data_sg, se_cmd->t_bidi_data_nents); | |
557 | } else if (se_cmd->data_direction == DMA_FROM_DEVICE) { | |
f97ec7db IT |
558 | gather_and_free_data_area(udev, |
559 | se_cmd->t_data_sg, se_cmd->t_data_nents); | |
7c9e7a6f AG |
560 | } else if (se_cmd->data_direction == DMA_TO_DEVICE) { |
561 | UPDATE_HEAD(udev->data_tail, cmd->data_length, udev->data_size); | |
2bc396a2 IT |
562 | } else if (se_cmd->data_direction != DMA_NONE) { |
563 | pr_warn("TCMU: data direction was %d!\n", | |
564 | se_cmd->data_direction); | |
7c9e7a6f AG |
565 | } |
566 | ||
567 | target_complete_cmd(cmd->se_cmd, entry->rsp.scsi_status); | |
568 | cmd->se_cmd = NULL; | |
569 | ||
570 | kmem_cache_free(tcmu_cmd_cache, cmd); | |
571 | } | |
572 | ||
573 | static unsigned int tcmu_handle_completions(struct tcmu_dev *udev) | |
574 | { | |
575 | struct tcmu_mailbox *mb; | |
7c9e7a6f AG |
576 | unsigned long flags; |
577 | int handled = 0; | |
578 | ||
579 | if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) { | |
580 | pr_err("ring broken, not handling completions\n"); | |
581 | return 0; | |
582 | } | |
583 | ||
584 | spin_lock_irqsave(&udev->cmdr_lock, flags); | |
585 | ||
586 | mb = udev->mb_addr; | |
587 | tcmu_flush_dcache_range(mb, sizeof(*mb)); | |
588 | ||
589 | while (udev->cmdr_last_cleaned != ACCESS_ONCE(mb->cmd_tail)) { | |
590 | ||
591 | struct tcmu_cmd_entry *entry = (void *) mb + CMDR_OFF + udev->cmdr_last_cleaned; | |
592 | struct tcmu_cmd *cmd; | |
593 | ||
594 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
595 | ||
0ad46af8 AG |
596 | if (tcmu_hdr_get_op(entry->hdr.len_op) == TCMU_OP_PAD) { |
597 | UPDATE_HEAD(udev->cmdr_last_cleaned, | |
598 | tcmu_hdr_get_len(entry->hdr.len_op), | |
599 | udev->cmdr_size); | |
7c9e7a6f AG |
600 | continue; |
601 | } | |
0ad46af8 | 602 | WARN_ON(tcmu_hdr_get_op(entry->hdr.len_op) != TCMU_OP_CMD); |
7c9e7a6f AG |
603 | |
604 | spin_lock(&udev->commands_lock); | |
0ad46af8 | 605 | cmd = idr_find(&udev->commands, entry->hdr.cmd_id); |
7c9e7a6f AG |
606 | if (cmd) |
607 | idr_remove(&udev->commands, cmd->cmd_id); | |
608 | spin_unlock(&udev->commands_lock); | |
609 | ||
610 | if (!cmd) { | |
611 | pr_err("cmd_id not found, ring is broken\n"); | |
612 | set_bit(TCMU_DEV_BIT_BROKEN, &udev->flags); | |
613 | break; | |
614 | } | |
615 | ||
616 | tcmu_handle_completion(cmd, entry); | |
617 | ||
0ad46af8 AG |
618 | UPDATE_HEAD(udev->cmdr_last_cleaned, |
619 | tcmu_hdr_get_len(entry->hdr.len_op), | |
620 | udev->cmdr_size); | |
7c9e7a6f AG |
621 | |
622 | handled++; | |
623 | } | |
624 | ||
625 | if (mb->cmd_tail == mb->cmd_head) | |
626 | del_timer(&udev->timeout); /* no more pending cmds */ | |
627 | ||
628 | spin_unlock_irqrestore(&udev->cmdr_lock, flags); | |
629 | ||
630 | wake_up(&udev->wait_cmdr); | |
631 | ||
632 | return handled; | |
633 | } | |
634 | ||
635 | static int tcmu_check_expired_cmd(int id, void *p, void *data) | |
636 | { | |
637 | struct tcmu_cmd *cmd = p; | |
638 | ||
639 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) | |
640 | return 0; | |
641 | ||
611e2267 | 642 | if (!time_after(jiffies, cmd->deadline)) |
7c9e7a6f AG |
643 | return 0; |
644 | ||
645 | set_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags); | |
646 | target_complete_cmd(cmd->se_cmd, SAM_STAT_CHECK_CONDITION); | |
647 | cmd->se_cmd = NULL; | |
648 | ||
649 | kmem_cache_free(tcmu_cmd_cache, cmd); | |
650 | ||
651 | return 0; | |
652 | } | |
653 | ||
654 | static void tcmu_device_timedout(unsigned long data) | |
655 | { | |
656 | struct tcmu_dev *udev = (struct tcmu_dev *)data; | |
657 | unsigned long flags; | |
658 | int handled; | |
659 | ||
660 | handled = tcmu_handle_completions(udev); | |
661 | ||
662 | pr_warn("%d completions handled from timeout\n", handled); | |
663 | ||
664 | spin_lock_irqsave(&udev->commands_lock, flags); | |
665 | idr_for_each(&udev->commands, tcmu_check_expired_cmd, NULL); | |
666 | spin_unlock_irqrestore(&udev->commands_lock, flags); | |
667 | ||
668 | /* | |
669 | * We don't need to wakeup threads on wait_cmdr since they have their | |
670 | * own timeout. | |
671 | */ | |
672 | } | |
673 | ||
674 | static int tcmu_attach_hba(struct se_hba *hba, u32 host_id) | |
675 | { | |
676 | struct tcmu_hba *tcmu_hba; | |
677 | ||
678 | tcmu_hba = kzalloc(sizeof(struct tcmu_hba), GFP_KERNEL); | |
679 | if (!tcmu_hba) | |
680 | return -ENOMEM; | |
681 | ||
682 | tcmu_hba->host_id = host_id; | |
683 | hba->hba_ptr = tcmu_hba; | |
684 | ||
685 | return 0; | |
686 | } | |
687 | ||
688 | static void tcmu_detach_hba(struct se_hba *hba) | |
689 | { | |
690 | kfree(hba->hba_ptr); | |
691 | hba->hba_ptr = NULL; | |
692 | } | |
693 | ||
694 | static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name) | |
695 | { | |
696 | struct tcmu_dev *udev; | |
697 | ||
698 | udev = kzalloc(sizeof(struct tcmu_dev), GFP_KERNEL); | |
699 | if (!udev) | |
700 | return NULL; | |
701 | ||
702 | udev->name = kstrdup(name, GFP_KERNEL); | |
703 | if (!udev->name) { | |
704 | kfree(udev); | |
705 | return NULL; | |
706 | } | |
707 | ||
708 | udev->hba = hba; | |
709 | ||
710 | init_waitqueue_head(&udev->wait_cmdr); | |
711 | spin_lock_init(&udev->cmdr_lock); | |
712 | ||
713 | idr_init(&udev->commands); | |
714 | spin_lock_init(&udev->commands_lock); | |
715 | ||
716 | setup_timer(&udev->timeout, tcmu_device_timedout, | |
717 | (unsigned long)udev); | |
718 | ||
7c9e7a6f AG |
719 | return &udev->se_dev; |
720 | } | |
721 | ||
722 | static int tcmu_irqcontrol(struct uio_info *info, s32 irq_on) | |
723 | { | |
724 | struct tcmu_dev *tcmu_dev = container_of(info, struct tcmu_dev, uio_info); | |
725 | ||
726 | tcmu_handle_completions(tcmu_dev); | |
727 | ||
728 | return 0; | |
729 | } | |
730 | ||
731 | /* | |
732 | * mmap code from uio.c. Copied here because we want to hook mmap() | |
733 | * and this stuff must come along. | |
734 | */ | |
735 | static int tcmu_find_mem_index(struct vm_area_struct *vma) | |
736 | { | |
737 | struct tcmu_dev *udev = vma->vm_private_data; | |
738 | struct uio_info *info = &udev->uio_info; | |
739 | ||
740 | if (vma->vm_pgoff < MAX_UIO_MAPS) { | |
741 | if (info->mem[vma->vm_pgoff].size == 0) | |
742 | return -1; | |
743 | return (int)vma->vm_pgoff; | |
744 | } | |
745 | return -1; | |
746 | } | |
747 | ||
748 | static int tcmu_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf) | |
749 | { | |
750 | struct tcmu_dev *udev = vma->vm_private_data; | |
751 | struct uio_info *info = &udev->uio_info; | |
752 | struct page *page; | |
753 | unsigned long offset; | |
754 | void *addr; | |
755 | ||
756 | int mi = tcmu_find_mem_index(vma); | |
757 | if (mi < 0) | |
758 | return VM_FAULT_SIGBUS; | |
759 | ||
760 | /* | |
761 | * We need to subtract mi because userspace uses offset = N*PAGE_SIZE | |
762 | * to use mem[N]. | |
763 | */ | |
764 | offset = (vmf->pgoff - mi) << PAGE_SHIFT; | |
765 | ||
766 | addr = (void *)(unsigned long)info->mem[mi].addr + offset; | |
767 | if (info->mem[mi].memtype == UIO_MEM_LOGICAL) | |
768 | page = virt_to_page(addr); | |
769 | else | |
770 | page = vmalloc_to_page(addr); | |
771 | get_page(page); | |
772 | vmf->page = page; | |
773 | return 0; | |
774 | } | |
775 | ||
776 | static const struct vm_operations_struct tcmu_vm_ops = { | |
777 | .fault = tcmu_vma_fault, | |
778 | }; | |
779 | ||
780 | static int tcmu_mmap(struct uio_info *info, struct vm_area_struct *vma) | |
781 | { | |
782 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); | |
783 | ||
784 | vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; | |
785 | vma->vm_ops = &tcmu_vm_ops; | |
786 | ||
787 | vma->vm_private_data = udev; | |
788 | ||
789 | /* Ensure the mmap is exactly the right size */ | |
790 | if (vma_pages(vma) != (TCMU_RING_SIZE >> PAGE_SHIFT)) | |
791 | return -EINVAL; | |
792 | ||
793 | return 0; | |
794 | } | |
795 | ||
796 | static int tcmu_open(struct uio_info *info, struct inode *inode) | |
797 | { | |
798 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); | |
799 | ||
800 | /* O_EXCL not supported for char devs, so fake it? */ | |
801 | if (test_and_set_bit(TCMU_DEV_BIT_OPEN, &udev->flags)) | |
802 | return -EBUSY; | |
803 | ||
804 | pr_debug("open\n"); | |
805 | ||
806 | return 0; | |
807 | } | |
808 | ||
809 | static int tcmu_release(struct uio_info *info, struct inode *inode) | |
810 | { | |
811 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); | |
812 | ||
813 | clear_bit(TCMU_DEV_BIT_OPEN, &udev->flags); | |
814 | ||
815 | pr_debug("close\n"); | |
816 | ||
817 | return 0; | |
818 | } | |
819 | ||
820 | static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name, int minor) | |
821 | { | |
822 | struct sk_buff *skb; | |
823 | void *msg_header; | |
6e14eab9 | 824 | int ret = -ENOMEM; |
7c9e7a6f AG |
825 | |
826 | skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); | |
827 | if (!skb) | |
6e14eab9 | 828 | return ret; |
7c9e7a6f AG |
829 | |
830 | msg_header = genlmsg_put(skb, 0, 0, &tcmu_genl_family, 0, cmd); | |
6e14eab9 NB |
831 | if (!msg_header) |
832 | goto free_skb; | |
7c9e7a6f AG |
833 | |
834 | ret = nla_put_string(skb, TCMU_ATTR_DEVICE, name); | |
6e14eab9 NB |
835 | if (ret < 0) |
836 | goto free_skb; | |
7c9e7a6f AG |
837 | |
838 | ret = nla_put_u32(skb, TCMU_ATTR_MINOR, minor); | |
6e14eab9 NB |
839 | if (ret < 0) |
840 | goto free_skb; | |
7c9e7a6f | 841 | |
053c095a | 842 | genlmsg_end(skb, msg_header); |
7c9e7a6f | 843 | |
20c08b36 | 844 | ret = genlmsg_multicast_allns(&tcmu_genl_family, skb, 0, |
7c9e7a6f AG |
845 | TCMU_MCGRP_CONFIG, GFP_KERNEL); |
846 | ||
847 | /* We don't care if no one is listening */ | |
848 | if (ret == -ESRCH) | |
849 | ret = 0; | |
850 | ||
851 | return ret; | |
6e14eab9 NB |
852 | free_skb: |
853 | nlmsg_free(skb); | |
854 | return ret; | |
7c9e7a6f AG |
855 | } |
856 | ||
857 | static int tcmu_configure_device(struct se_device *dev) | |
858 | { | |
859 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
860 | struct tcmu_hba *hba = udev->hba->hba_ptr; | |
861 | struct uio_info *info; | |
862 | struct tcmu_mailbox *mb; | |
863 | size_t size; | |
864 | size_t used; | |
865 | int ret = 0; | |
866 | char *str; | |
867 | ||
868 | info = &udev->uio_info; | |
869 | ||
870 | size = snprintf(NULL, 0, "tcm-user/%u/%s/%s", hba->host_id, udev->name, | |
871 | udev->dev_config); | |
872 | size += 1; /* for \0 */ | |
873 | str = kmalloc(size, GFP_KERNEL); | |
874 | if (!str) | |
875 | return -ENOMEM; | |
876 | ||
877 | used = snprintf(str, size, "tcm-user/%u/%s", hba->host_id, udev->name); | |
878 | ||
879 | if (udev->dev_config[0]) | |
880 | snprintf(str + used, size - used, "/%s", udev->dev_config); | |
881 | ||
882 | info->name = str; | |
883 | ||
884 | udev->mb_addr = vzalloc(TCMU_RING_SIZE); | |
885 | if (!udev->mb_addr) { | |
886 | ret = -ENOMEM; | |
887 | goto err_vzalloc; | |
888 | } | |
889 | ||
890 | /* mailbox fits in first part of CMDR space */ | |
891 | udev->cmdr_size = CMDR_SIZE - CMDR_OFF; | |
892 | udev->data_off = CMDR_SIZE; | |
893 | udev->data_size = TCMU_RING_SIZE - CMDR_SIZE; | |
894 | ||
895 | mb = udev->mb_addr; | |
0ad46af8 | 896 | mb->version = TCMU_MAILBOX_VERSION; |
7c9e7a6f AG |
897 | mb->cmdr_off = CMDR_OFF; |
898 | mb->cmdr_size = udev->cmdr_size; | |
899 | ||
900 | WARN_ON(!PAGE_ALIGNED(udev->data_off)); | |
901 | WARN_ON(udev->data_size % PAGE_SIZE); | |
902 | ||
ac64a2ce | 903 | info->version = __stringify(TCMU_MAILBOX_VERSION); |
7c9e7a6f AG |
904 | |
905 | info->mem[0].name = "tcm-user command & data buffer"; | |
906 | info->mem[0].addr = (phys_addr_t) udev->mb_addr; | |
907 | info->mem[0].size = TCMU_RING_SIZE; | |
908 | info->mem[0].memtype = UIO_MEM_VIRTUAL; | |
909 | ||
910 | info->irqcontrol = tcmu_irqcontrol; | |
911 | info->irq = UIO_IRQ_CUSTOM; | |
912 | ||
913 | info->mmap = tcmu_mmap; | |
914 | info->open = tcmu_open; | |
915 | info->release = tcmu_release; | |
916 | ||
917 | ret = uio_register_device(tcmu_root_device, info); | |
918 | if (ret) | |
919 | goto err_register; | |
920 | ||
81ee28de SY |
921 | /* User can set hw_block_size before enable the device */ |
922 | if (dev->dev_attrib.hw_block_size == 0) | |
923 | dev->dev_attrib.hw_block_size = 512; | |
7c9e7a6f | 924 | /* Other attributes can be configured in userspace */ |
7c9e7a6f AG |
925 | dev->dev_attrib.hw_max_sectors = 128; |
926 | dev->dev_attrib.hw_queue_depth = 128; | |
927 | ||
928 | ret = tcmu_netlink_event(TCMU_CMD_ADDED_DEVICE, udev->uio_info.name, | |
929 | udev->uio_info.uio_dev->minor); | |
930 | if (ret) | |
931 | goto err_netlink; | |
932 | ||
933 | return 0; | |
934 | ||
935 | err_netlink: | |
936 | uio_unregister_device(&udev->uio_info); | |
937 | err_register: | |
938 | vfree(udev->mb_addr); | |
939 | err_vzalloc: | |
940 | kfree(info->name); | |
941 | ||
942 | return ret; | |
943 | } | |
944 | ||
945 | static int tcmu_check_pending_cmd(int id, void *p, void *data) | |
946 | { | |
947 | struct tcmu_cmd *cmd = p; | |
948 | ||
949 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) | |
950 | return 0; | |
951 | return -EINVAL; | |
952 | } | |
953 | ||
4cc987ea NB |
954 | static void tcmu_dev_call_rcu(struct rcu_head *p) |
955 | { | |
956 | struct se_device *dev = container_of(p, struct se_device, rcu_head); | |
957 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
958 | ||
959 | kfree(udev); | |
960 | } | |
961 | ||
7c9e7a6f AG |
962 | static void tcmu_free_device(struct se_device *dev) |
963 | { | |
964 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
965 | int i; | |
966 | ||
967 | del_timer_sync(&udev->timeout); | |
968 | ||
969 | vfree(udev->mb_addr); | |
970 | ||
971 | /* Upper layer should drain all requests before calling this */ | |
972 | spin_lock_irq(&udev->commands_lock); | |
973 | i = idr_for_each(&udev->commands, tcmu_check_pending_cmd, NULL); | |
974 | idr_destroy(&udev->commands); | |
975 | spin_unlock_irq(&udev->commands_lock); | |
976 | WARN_ON(i); | |
977 | ||
978 | /* Device was configured */ | |
979 | if (udev->uio_info.uio_dev) { | |
980 | tcmu_netlink_event(TCMU_CMD_REMOVED_DEVICE, udev->uio_info.name, | |
981 | udev->uio_info.uio_dev->minor); | |
982 | ||
983 | uio_unregister_device(&udev->uio_info); | |
984 | kfree(udev->uio_info.name); | |
985 | kfree(udev->name); | |
986 | } | |
4cc987ea | 987 | call_rcu(&dev->rcu_head, tcmu_dev_call_rcu); |
7c9e7a6f AG |
988 | } |
989 | ||
990 | enum { | |
9c1cd1b6 | 991 | Opt_dev_config, Opt_dev_size, Opt_hw_block_size, Opt_err, |
7c9e7a6f AG |
992 | }; |
993 | ||
994 | static match_table_t tokens = { | |
995 | {Opt_dev_config, "dev_config=%s"}, | |
996 | {Opt_dev_size, "dev_size=%u"}, | |
9c1cd1b6 | 997 | {Opt_hw_block_size, "hw_block_size=%u"}, |
7c9e7a6f AG |
998 | {Opt_err, NULL} |
999 | }; | |
1000 | ||
1001 | static ssize_t tcmu_set_configfs_dev_params(struct se_device *dev, | |
1002 | const char *page, ssize_t count) | |
1003 | { | |
1004 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
1005 | char *orig, *ptr, *opts, *arg_p; | |
1006 | substring_t args[MAX_OPT_ARGS]; | |
1007 | int ret = 0, token; | |
9c1cd1b6 | 1008 | unsigned long tmp_ul; |
7c9e7a6f AG |
1009 | |
1010 | opts = kstrdup(page, GFP_KERNEL); | |
1011 | if (!opts) | |
1012 | return -ENOMEM; | |
1013 | ||
1014 | orig = opts; | |
1015 | ||
1016 | while ((ptr = strsep(&opts, ",\n")) != NULL) { | |
1017 | if (!*ptr) | |
1018 | continue; | |
1019 | ||
1020 | token = match_token(ptr, tokens, args); | |
1021 | switch (token) { | |
1022 | case Opt_dev_config: | |
1023 | if (match_strlcpy(udev->dev_config, &args[0], | |
1024 | TCMU_CONFIG_LEN) == 0) { | |
1025 | ret = -EINVAL; | |
1026 | break; | |
1027 | } | |
1028 | pr_debug("TCMU: Referencing Path: %s\n", udev->dev_config); | |
1029 | break; | |
1030 | case Opt_dev_size: | |
1031 | arg_p = match_strdup(&args[0]); | |
1032 | if (!arg_p) { | |
1033 | ret = -ENOMEM; | |
1034 | break; | |
1035 | } | |
1036 | ret = kstrtoul(arg_p, 0, (unsigned long *) &udev->dev_size); | |
1037 | kfree(arg_p); | |
1038 | if (ret < 0) | |
1039 | pr_err("kstrtoul() failed for dev_size=\n"); | |
1040 | break; | |
9c1cd1b6 AG |
1041 | case Opt_hw_block_size: |
1042 | arg_p = match_strdup(&args[0]); | |
1043 | if (!arg_p) { | |
1044 | ret = -ENOMEM; | |
1045 | break; | |
1046 | } | |
1047 | ret = kstrtoul(arg_p, 0, &tmp_ul); | |
1048 | kfree(arg_p); | |
1049 | if (ret < 0) { | |
1050 | pr_err("kstrtoul() failed for hw_block_size=\n"); | |
1051 | break; | |
1052 | } | |
1053 | if (!tmp_ul) { | |
1054 | pr_err("hw_block_size must be nonzero\n"); | |
1055 | break; | |
1056 | } | |
1057 | dev->dev_attrib.hw_block_size = tmp_ul; | |
1058 | break; | |
7c9e7a6f AG |
1059 | default: |
1060 | break; | |
1061 | } | |
1062 | } | |
1063 | ||
1064 | kfree(orig); | |
1065 | return (!ret) ? count : ret; | |
1066 | } | |
1067 | ||
1068 | static ssize_t tcmu_show_configfs_dev_params(struct se_device *dev, char *b) | |
1069 | { | |
1070 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
1071 | ssize_t bl = 0; | |
1072 | ||
1073 | bl = sprintf(b + bl, "Config: %s ", | |
1074 | udev->dev_config[0] ? udev->dev_config : "NULL"); | |
8ee83a74 | 1075 | bl += sprintf(b + bl, "Size: %zu\n", udev->dev_size); |
7c9e7a6f AG |
1076 | |
1077 | return bl; | |
1078 | } | |
1079 | ||
1080 | static sector_t tcmu_get_blocks(struct se_device *dev) | |
1081 | { | |
1082 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
1083 | ||
1084 | return div_u64(udev->dev_size - dev->dev_attrib.block_size, | |
1085 | dev->dev_attrib.block_size); | |
1086 | } | |
1087 | ||
1088 | static sense_reason_t | |
9c1cd1b6 | 1089 | tcmu_pass_op(struct se_cmd *se_cmd) |
7c9e7a6f | 1090 | { |
9c1cd1b6 | 1091 | int ret = tcmu_queue_cmd(se_cmd); |
7c9e7a6f AG |
1092 | |
1093 | if (ret != 0) | |
1094 | return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; | |
1095 | else | |
1096 | return TCM_NO_SENSE; | |
1097 | } | |
1098 | ||
1099 | static sense_reason_t | |
9c1cd1b6 | 1100 | tcmu_parse_cdb(struct se_cmd *cmd) |
7c9e7a6f | 1101 | { |
7bfea53b | 1102 | return passthrough_parse_cdb(cmd, tcmu_pass_op); |
7c9e7a6f AG |
1103 | } |
1104 | ||
0a06d430 | 1105 | static const struct target_backend_ops tcmu_ops = { |
7c9e7a6f | 1106 | .name = "user", |
7c9e7a6f | 1107 | .owner = THIS_MODULE, |
a3541703 | 1108 | .transport_flags = TRANSPORT_FLAG_PASSTHROUGH, |
7c9e7a6f AG |
1109 | .attach_hba = tcmu_attach_hba, |
1110 | .detach_hba = tcmu_detach_hba, | |
1111 | .alloc_device = tcmu_alloc_device, | |
1112 | .configure_device = tcmu_configure_device, | |
1113 | .free_device = tcmu_free_device, | |
1114 | .parse_cdb = tcmu_parse_cdb, | |
1115 | .set_configfs_dev_params = tcmu_set_configfs_dev_params, | |
1116 | .show_configfs_dev_params = tcmu_show_configfs_dev_params, | |
1117 | .get_device_type = sbc_get_device_type, | |
1118 | .get_blocks = tcmu_get_blocks, | |
5873c4d1 | 1119 | .tb_dev_attrib_attrs = passthrough_attrib_attrs, |
7c9e7a6f AG |
1120 | }; |
1121 | ||
1122 | static int __init tcmu_module_init(void) | |
1123 | { | |
1124 | int ret; | |
1125 | ||
1126 | BUILD_BUG_ON((sizeof(struct tcmu_cmd_entry) % TCMU_OP_ALIGN_SIZE) != 0); | |
1127 | ||
1128 | tcmu_cmd_cache = kmem_cache_create("tcmu_cmd_cache", | |
1129 | sizeof(struct tcmu_cmd), | |
1130 | __alignof__(struct tcmu_cmd), | |
1131 | 0, NULL); | |
1132 | if (!tcmu_cmd_cache) | |
1133 | return -ENOMEM; | |
1134 | ||
1135 | tcmu_root_device = root_device_register("tcm_user"); | |
1136 | if (IS_ERR(tcmu_root_device)) { | |
1137 | ret = PTR_ERR(tcmu_root_device); | |
1138 | goto out_free_cache; | |
1139 | } | |
1140 | ||
1141 | ret = genl_register_family(&tcmu_genl_family); | |
1142 | if (ret < 0) { | |
1143 | goto out_unreg_device; | |
1144 | } | |
1145 | ||
0a06d430 | 1146 | ret = transport_backend_register(&tcmu_ops); |
7c9e7a6f AG |
1147 | if (ret) |
1148 | goto out_unreg_genl; | |
1149 | ||
1150 | return 0; | |
1151 | ||
1152 | out_unreg_genl: | |
1153 | genl_unregister_family(&tcmu_genl_family); | |
1154 | out_unreg_device: | |
1155 | root_device_unregister(tcmu_root_device); | |
1156 | out_free_cache: | |
1157 | kmem_cache_destroy(tcmu_cmd_cache); | |
1158 | ||
1159 | return ret; | |
1160 | } | |
1161 | ||
1162 | static void __exit tcmu_module_exit(void) | |
1163 | { | |
0a06d430 | 1164 | target_backend_unregister(&tcmu_ops); |
7c9e7a6f AG |
1165 | genl_unregister_family(&tcmu_genl_family); |
1166 | root_device_unregister(tcmu_root_device); | |
1167 | kmem_cache_destroy(tcmu_cmd_cache); | |
1168 | } | |
1169 | ||
1170 | MODULE_DESCRIPTION("TCM USER subsystem plugin"); | |
1171 | MODULE_AUTHOR("Shaohua Li <shli@kernel.org>"); | |
1172 | MODULE_AUTHOR("Andy Grover <agrover@redhat.com>"); | |
1173 | MODULE_LICENSE("GPL"); | |
1174 | ||
1175 | module_init(tcmu_module_init); | |
1176 | module_exit(tcmu_module_exit); |