]>
Commit | Line | Data |
---|---|---|
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> |
26418649 | 29 | #include <linux/bitops.h> |
7c9e7a6f | 30 | #include <net/genetlink.h> |
ba929992 BVA |
31 | #include <scsi/scsi_common.h> |
32 | #include <scsi/scsi_proto.h> | |
7c9e7a6f AG |
33 | #include <target/target_core_base.h> |
34 | #include <target/target_core_fabric.h> | |
35 | #include <target/target_core_backend.h> | |
e9f720d6 | 36 | |
7c9e7a6f AG |
37 | #include <linux/target_core_user.h> |
38 | ||
39 | /* | |
40 | * Define a shared-memory interface for LIO to pass SCSI commands and | |
41 | * data to userspace for processing. This is to allow backends that | |
42 | * are too complex for in-kernel support to be possible. | |
43 | * | |
44 | * It uses the UIO framework to do a lot of the device-creation and | |
45 | * introspection work for us. | |
46 | * | |
47 | * See the .h file for how the ring is laid out. Note that while the | |
48 | * command ring is defined, the particulars of the data area are | |
49 | * not. Offset values in the command entry point to other locations | |
50 | * internal to the mmap()ed area. There is separate space outside the | |
51 | * command ring for data buffers. This leaves maximum flexibility for | |
52 | * moving buffer allocations, or even page flipping or other | |
53 | * allocation techniques, without altering the command ring layout. | |
54 | * | |
55 | * SECURITY: | |
56 | * The user process must be assumed to be malicious. There's no way to | |
57 | * prevent it breaking the command ring protocol if it wants, but in | |
58 | * order to prevent other issues we must only ever read *data* from | |
59 | * the shared memory area, not offsets or sizes. This applies to | |
60 | * command ring entries as well as the mailbox. Extra code needed for | |
61 | * this may have a 'UAM' comment. | |
62 | */ | |
63 | ||
64 | ||
65 | #define TCMU_TIME_OUT (30 * MSEC_PER_SEC) | |
66 | ||
26418649 SY |
67 | #define DATA_BLOCK_BITS 256 |
68 | #define DATA_BLOCK_SIZE 4096 | |
69 | ||
7c9e7a6f | 70 | #define CMDR_SIZE (16 * 4096) |
26418649 | 71 | #define DATA_SIZE (DATA_BLOCK_BITS * DATA_BLOCK_SIZE) |
7c9e7a6f AG |
72 | |
73 | #define TCMU_RING_SIZE (CMDR_SIZE + DATA_SIZE) | |
74 | ||
75 | static struct device *tcmu_root_device; | |
76 | ||
77 | struct tcmu_hba { | |
78 | u32 host_id; | |
79 | }; | |
80 | ||
7c9e7a6f AG |
81 | #define TCMU_CONFIG_LEN 256 |
82 | ||
83 | struct tcmu_dev { | |
84 | struct se_device se_dev; | |
85 | ||
86 | char *name; | |
87 | struct se_hba *hba; | |
88 | ||
89 | #define TCMU_DEV_BIT_OPEN 0 | |
90 | #define TCMU_DEV_BIT_BROKEN 1 | |
91 | unsigned long flags; | |
7c9e7a6f AG |
92 | |
93 | struct uio_info uio_info; | |
94 | ||
95 | struct tcmu_mailbox *mb_addr; | |
96 | size_t dev_size; | |
97 | u32 cmdr_size; | |
98 | u32 cmdr_last_cleaned; | |
3d9b9555 | 99 | /* Offset of data area from start of mb */ |
26418649 | 100 | /* Must add data_off and mb_addr to get the address */ |
7c9e7a6f AG |
101 | size_t data_off; |
102 | size_t data_size; | |
26418649 SY |
103 | |
104 | DECLARE_BITMAP(data_bitmap, DATA_BLOCK_BITS); | |
7c9e7a6f AG |
105 | |
106 | wait_queue_head_t wait_cmdr; | |
107 | /* TODO should this be a mutex? */ | |
108 | spinlock_t cmdr_lock; | |
109 | ||
110 | struct idr commands; | |
111 | spinlock_t commands_lock; | |
112 | ||
113 | struct timer_list timeout; | |
114 | ||
115 | char dev_config[TCMU_CONFIG_LEN]; | |
116 | }; | |
117 | ||
118 | #define TCMU_DEV(_se_dev) container_of(_se_dev, struct tcmu_dev, se_dev) | |
119 | ||
120 | #define CMDR_OFF sizeof(struct tcmu_mailbox) | |
121 | ||
122 | struct tcmu_cmd { | |
123 | struct se_cmd *se_cmd; | |
124 | struct tcmu_dev *tcmu_dev; | |
125 | ||
126 | uint16_t cmd_id; | |
127 | ||
26418649 | 128 | /* Can't use se_cmd when cleaning up expired cmds, because if |
7c9e7a6f | 129 | cmd has been completed then accessing se_cmd is off limits */ |
26418649 | 130 | DECLARE_BITMAP(data_bitmap, DATA_BLOCK_BITS); |
7c9e7a6f AG |
131 | |
132 | unsigned long deadline; | |
133 | ||
134 | #define TCMU_CMD_BIT_EXPIRED 0 | |
135 | unsigned long flags; | |
136 | }; | |
137 | ||
138 | static struct kmem_cache *tcmu_cmd_cache; | |
139 | ||
140 | /* multicast group */ | |
141 | enum tcmu_multicast_groups { | |
142 | TCMU_MCGRP_CONFIG, | |
143 | }; | |
144 | ||
145 | static const struct genl_multicast_group tcmu_mcgrps[] = { | |
146 | [TCMU_MCGRP_CONFIG] = { .name = "config", }, | |
147 | }; | |
148 | ||
149 | /* Our generic netlink family */ | |
150 | static struct genl_family tcmu_genl_family = { | |
151 | .id = GENL_ID_GENERATE, | |
152 | .hdrsize = 0, | |
153 | .name = "TCM-USER", | |
154 | .version = 1, | |
155 | .maxattr = TCMU_ATTR_MAX, | |
156 | .mcgrps = tcmu_mcgrps, | |
157 | .n_mcgrps = ARRAY_SIZE(tcmu_mcgrps), | |
20c08b36 | 158 | .netnsok = true, |
7c9e7a6f AG |
159 | }; |
160 | ||
161 | static struct tcmu_cmd *tcmu_alloc_cmd(struct se_cmd *se_cmd) | |
162 | { | |
163 | struct se_device *se_dev = se_cmd->se_dev; | |
164 | struct tcmu_dev *udev = TCMU_DEV(se_dev); | |
165 | struct tcmu_cmd *tcmu_cmd; | |
166 | int cmd_id; | |
167 | ||
168 | tcmu_cmd = kmem_cache_zalloc(tcmu_cmd_cache, GFP_KERNEL); | |
169 | if (!tcmu_cmd) | |
170 | return NULL; | |
171 | ||
172 | tcmu_cmd->se_cmd = se_cmd; | |
173 | tcmu_cmd->tcmu_dev = udev; | |
7c9e7a6f AG |
174 | tcmu_cmd->deadline = jiffies + msecs_to_jiffies(TCMU_TIME_OUT); |
175 | ||
176 | idr_preload(GFP_KERNEL); | |
177 | spin_lock_irq(&udev->commands_lock); | |
178 | cmd_id = idr_alloc(&udev->commands, tcmu_cmd, 0, | |
179 | USHRT_MAX, GFP_NOWAIT); | |
180 | spin_unlock_irq(&udev->commands_lock); | |
181 | idr_preload_end(); | |
182 | ||
183 | if (cmd_id < 0) { | |
184 | kmem_cache_free(tcmu_cmd_cache, tcmu_cmd); | |
185 | return NULL; | |
186 | } | |
187 | tcmu_cmd->cmd_id = cmd_id; | |
188 | ||
189 | return tcmu_cmd; | |
190 | } | |
191 | ||
192 | static inline void tcmu_flush_dcache_range(void *vaddr, size_t size) | |
193 | { | |
b75d8063 | 194 | unsigned long offset = offset_in_page(vaddr); |
7c9e7a6f AG |
195 | |
196 | size = round_up(size+offset, PAGE_SIZE); | |
197 | vaddr -= offset; | |
198 | ||
199 | while (size) { | |
200 | flush_dcache_page(virt_to_page(vaddr)); | |
201 | size -= PAGE_SIZE; | |
202 | } | |
203 | } | |
204 | ||
205 | /* | |
206 | * Some ring helper functions. We don't assume size is a power of 2 so | |
207 | * we can't use circ_buf.h. | |
208 | */ | |
209 | static inline size_t spc_used(size_t head, size_t tail, size_t size) | |
210 | { | |
211 | int diff = head - tail; | |
212 | ||
213 | if (diff >= 0) | |
214 | return diff; | |
215 | else | |
216 | return size + diff; | |
217 | } | |
218 | ||
219 | static inline size_t spc_free(size_t head, size_t tail, size_t size) | |
220 | { | |
221 | /* Keep 1 byte unused or we can't tell full from empty */ | |
222 | return (size - spc_used(head, tail, size) - 1); | |
223 | } | |
224 | ||
225 | static inline size_t head_to_end(size_t head, size_t size) | |
226 | { | |
227 | return size - head; | |
228 | } | |
229 | ||
f1dbd087 SY |
230 | static inline void new_iov(struct iovec **iov, int *iov_cnt, |
231 | struct tcmu_dev *udev) | |
232 | { | |
233 | struct iovec *iovec; | |
234 | ||
235 | if (*iov_cnt != 0) | |
236 | (*iov)++; | |
237 | (*iov_cnt)++; | |
238 | ||
239 | iovec = *iov; | |
240 | memset(iovec, 0, sizeof(struct iovec)); | |
f1dbd087 SY |
241 | } |
242 | ||
7c9e7a6f AG |
243 | #define UPDATE_HEAD(head, used, size) smp_store_release(&head, ((head % size) + used) % size) |
244 | ||
26418649 SY |
245 | /* offset is relative to mb_addr */ |
246 | static inline size_t get_block_offset(struct tcmu_dev *dev, | |
247 | int block, int remaining) | |
248 | { | |
249 | return dev->data_off + block * DATA_BLOCK_SIZE + | |
250 | DATA_BLOCK_SIZE - remaining; | |
251 | } | |
252 | ||
253 | static inline size_t iov_tail(struct tcmu_dev *udev, struct iovec *iov) | |
254 | { | |
255 | return (size_t)iov->iov_base + iov->iov_len; | |
256 | } | |
257 | ||
f97ec7db IT |
258 | static void alloc_and_scatter_data_area(struct tcmu_dev *udev, |
259 | struct scatterlist *data_sg, unsigned int data_nents, | |
260 | struct iovec **iov, int *iov_cnt, bool copy_data) | |
261 | { | |
26418649 SY |
262 | int i, block; |
263 | int block_remaining = 0; | |
f97ec7db | 264 | void *from, *to; |
26418649 | 265 | size_t copy_bytes, to_offset; |
f97ec7db IT |
266 | struct scatterlist *sg; |
267 | ||
268 | for_each_sg(data_sg, sg, data_nents, i) { | |
26418649 | 269 | int sg_remaining = sg->length; |
f97ec7db | 270 | from = kmap_atomic(sg_page(sg)) + sg->offset; |
26418649 SY |
271 | while (sg_remaining > 0) { |
272 | if (block_remaining == 0) { | |
273 | block = find_first_zero_bit(udev->data_bitmap, | |
274 | DATA_BLOCK_BITS); | |
275 | block_remaining = DATA_BLOCK_SIZE; | |
276 | set_bit(block, udev->data_bitmap); | |
277 | } | |
278 | copy_bytes = min_t(size_t, sg_remaining, | |
279 | block_remaining); | |
280 | to_offset = get_block_offset(udev, block, | |
281 | block_remaining); | |
282 | to = (void *)udev->mb_addr + to_offset; | |
283 | if (*iov_cnt != 0 && | |
284 | to_offset == iov_tail(udev, *iov)) { | |
285 | (*iov)->iov_len += copy_bytes; | |
286 | } else { | |
287 | new_iov(iov, iov_cnt, udev); | |
288 | (*iov)->iov_base = (void __user *) to_offset; | |
289 | (*iov)->iov_len = copy_bytes; | |
290 | } | |
f97ec7db | 291 | if (copy_data) { |
26418649 SY |
292 | memcpy(to, from + sg->length - sg_remaining, |
293 | copy_bytes); | |
f97ec7db IT |
294 | tcmu_flush_dcache_range(to, copy_bytes); |
295 | } | |
26418649 SY |
296 | sg_remaining -= copy_bytes; |
297 | block_remaining -= copy_bytes; | |
f97ec7db | 298 | } |
e2e21bd8 | 299 | kunmap_atomic(from - sg->offset); |
f97ec7db IT |
300 | } |
301 | } | |
302 | ||
26418649 | 303 | static void free_data_area(struct tcmu_dev *udev, struct tcmu_cmd *cmd) |
0c28481f | 304 | { |
26418649 SY |
305 | bitmap_xor(udev->data_bitmap, udev->data_bitmap, cmd->data_bitmap, |
306 | DATA_BLOCK_BITS); | |
0c28481f SY |
307 | } |
308 | ||
26418649 SY |
309 | static void gather_data_area(struct tcmu_dev *udev, unsigned long *cmd_bitmap, |
310 | struct scatterlist *data_sg, unsigned int data_nents) | |
f97ec7db | 311 | { |
26418649 SY |
312 | int i, block; |
313 | int block_remaining = 0; | |
f97ec7db | 314 | void *from, *to; |
26418649 | 315 | size_t copy_bytes, from_offset; |
f97ec7db IT |
316 | struct scatterlist *sg; |
317 | ||
f97ec7db | 318 | for_each_sg(data_sg, sg, data_nents, i) { |
26418649 | 319 | int sg_remaining = sg->length; |
f97ec7db | 320 | to = kmap_atomic(sg_page(sg)) + sg->offset; |
26418649 SY |
321 | while (sg_remaining > 0) { |
322 | if (block_remaining == 0) { | |
323 | block = find_first_bit(cmd_bitmap, | |
324 | DATA_BLOCK_BITS); | |
325 | block_remaining = DATA_BLOCK_SIZE; | |
326 | clear_bit(block, cmd_bitmap); | |
327 | } | |
328 | copy_bytes = min_t(size_t, sg_remaining, | |
329 | block_remaining); | |
330 | from_offset = get_block_offset(udev, block, | |
331 | block_remaining); | |
332 | from = (void *) udev->mb_addr + from_offset; | |
f97ec7db | 333 | tcmu_flush_dcache_range(from, copy_bytes); |
26418649 SY |
334 | memcpy(to + sg->length - sg_remaining, from, |
335 | copy_bytes); | |
f97ec7db | 336 | |
26418649 SY |
337 | sg_remaining -= copy_bytes; |
338 | block_remaining -= copy_bytes; | |
f97ec7db | 339 | } |
e2e21bd8 | 340 | kunmap_atomic(to - sg->offset); |
f97ec7db IT |
341 | } |
342 | } | |
343 | ||
26418649 SY |
344 | static inline size_t spc_bitmap_free(unsigned long *bitmap) |
345 | { | |
346 | return DATA_BLOCK_SIZE * (DATA_BLOCK_BITS - | |
347 | bitmap_weight(bitmap, DATA_BLOCK_BITS)); | |
348 | } | |
349 | ||
7c9e7a6f | 350 | /* |
f97ec7db | 351 | * We can't queue a command until we have space available on the cmd ring *and* |
3d9b9555 | 352 | * space available on the data area. |
7c9e7a6f AG |
353 | * |
354 | * Called with ring lock held. | |
355 | */ | |
f56574a2 | 356 | static bool is_ring_space_avail(struct tcmu_dev *udev, size_t cmd_size, size_t data_needed) |
7c9e7a6f AG |
357 | { |
358 | struct tcmu_mailbox *mb = udev->mb_addr; | |
0241fd39 | 359 | size_t space, cmd_needed; |
7c9e7a6f AG |
360 | u32 cmd_head; |
361 | ||
362 | tcmu_flush_dcache_range(mb, sizeof(*mb)); | |
363 | ||
364 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
365 | ||
f56574a2 AG |
366 | /* |
367 | * If cmd end-of-ring space is too small then we need space for a NOP plus | |
368 | * original cmd - cmds are internally contiguous. | |
369 | */ | |
370 | if (head_to_end(cmd_head, udev->cmdr_size) >= cmd_size) | |
371 | cmd_needed = cmd_size; | |
372 | else | |
373 | cmd_needed = cmd_size + head_to_end(cmd_head, udev->cmdr_size); | |
374 | ||
7c9e7a6f AG |
375 | space = spc_free(cmd_head, udev->cmdr_last_cleaned, udev->cmdr_size); |
376 | if (space < cmd_needed) { | |
377 | pr_debug("no cmd space: %u %u %u\n", cmd_head, | |
378 | udev->cmdr_last_cleaned, udev->cmdr_size); | |
379 | return false; | |
380 | } | |
381 | ||
26418649 | 382 | space = spc_bitmap_free(udev->data_bitmap); |
7c9e7a6f | 383 | if (space < data_needed) { |
0241fd39 | 384 | pr_debug("no data space: only %zu available, but ask for %zu\n", |
26418649 | 385 | space, data_needed); |
7c9e7a6f AG |
386 | return false; |
387 | } | |
388 | ||
389 | return true; | |
390 | } | |
391 | ||
02eb924f AG |
392 | static sense_reason_t |
393 | tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd) | |
7c9e7a6f AG |
394 | { |
395 | struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; | |
396 | struct se_cmd *se_cmd = tcmu_cmd->se_cmd; | |
397 | size_t base_command_size, command_size; | |
7c9e7a6f | 398 | struct tcmu_mailbox *mb; |
7c9e7a6f | 399 | struct tcmu_cmd_entry *entry; |
7c9e7a6f | 400 | struct iovec *iov; |
f97ec7db | 401 | int iov_cnt; |
7c9e7a6f AG |
402 | uint32_t cmd_head; |
403 | uint64_t cdb_off; | |
f97ec7db | 404 | bool copy_to_data_area; |
26418649 SY |
405 | size_t data_length; |
406 | DECLARE_BITMAP(old_bitmap, DATA_BLOCK_BITS); | |
7c9e7a6f AG |
407 | |
408 | if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) | |
02eb924f | 409 | return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; |
7c9e7a6f AG |
410 | |
411 | /* | |
412 | * Must be a certain minimum size for response sense info, but | |
413 | * also may be larger if the iov array is large. | |
414 | * | |
26418649 SY |
415 | * We prepare way too many iovs for potential uses here, because it's |
416 | * expensive to tell how many regions are freed in the bitmap | |
7c9e7a6f | 417 | */ |
26418649 SY |
418 | base_command_size = max(offsetof(struct tcmu_cmd_entry, |
419 | req.iov[se_cmd->t_bidi_data_nents + | |
420 | se_cmd->t_data_nents]), | |
7c9e7a6f AG |
421 | sizeof(struct tcmu_cmd_entry)); |
422 | command_size = base_command_size | |
423 | + round_up(scsi_command_size(se_cmd->t_task_cdb), TCMU_OP_ALIGN_SIZE); | |
424 | ||
425 | WARN_ON(command_size & (TCMU_OP_ALIGN_SIZE-1)); | |
426 | ||
427 | spin_lock_irq(&udev->cmdr_lock); | |
428 | ||
429 | mb = udev->mb_addr; | |
430 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
26418649 SY |
431 | data_length = se_cmd->data_length; |
432 | if (se_cmd->se_cmd_flags & SCF_BIDI) { | |
433 | BUG_ON(!(se_cmd->t_bidi_data_sg && se_cmd->t_bidi_data_nents)); | |
434 | data_length += se_cmd->t_bidi_data_sg->length; | |
435 | } | |
554617b2 AG |
436 | if ((command_size > (udev->cmdr_size / 2)) || |
437 | data_length > udev->data_size) { | |
438 | pr_warn("TCMU: Request of size %zu/%zu is too big for %u/%zu " | |
3d9b9555 | 439 | "cmd ring/data area\n", command_size, data_length, |
7c9e7a6f | 440 | udev->cmdr_size, udev->data_size); |
554617b2 AG |
441 | spin_unlock_irq(&udev->cmdr_lock); |
442 | return TCM_INVALID_CDB_FIELD; | |
443 | } | |
7c9e7a6f | 444 | |
26418649 | 445 | while (!is_ring_space_avail(udev, command_size, data_length)) { |
7c9e7a6f AG |
446 | int ret; |
447 | DEFINE_WAIT(__wait); | |
448 | ||
449 | prepare_to_wait(&udev->wait_cmdr, &__wait, TASK_INTERRUPTIBLE); | |
450 | ||
451 | pr_debug("sleeping for ring space\n"); | |
452 | spin_unlock_irq(&udev->cmdr_lock); | |
453 | ret = schedule_timeout(msecs_to_jiffies(TCMU_TIME_OUT)); | |
454 | finish_wait(&udev->wait_cmdr, &__wait); | |
455 | if (!ret) { | |
456 | pr_warn("tcmu: command timed out\n"); | |
02eb924f | 457 | return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; |
7c9e7a6f AG |
458 | } |
459 | ||
460 | spin_lock_irq(&udev->cmdr_lock); | |
461 | ||
462 | /* We dropped cmdr_lock, cmd_head is stale */ | |
463 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
464 | } | |
465 | ||
f56574a2 AG |
466 | /* Insert a PAD if end-of-ring space is too small */ |
467 | if (head_to_end(cmd_head, udev->cmdr_size) < command_size) { | |
468 | size_t pad_size = head_to_end(cmd_head, udev->cmdr_size); | |
469 | ||
7c9e7a6f AG |
470 | entry = (void *) mb + CMDR_OFF + cmd_head; |
471 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
0ad46af8 AG |
472 | tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_PAD); |
473 | tcmu_hdr_set_len(&entry->hdr.len_op, pad_size); | |
474 | entry->hdr.cmd_id = 0; /* not used for PAD */ | |
475 | entry->hdr.kflags = 0; | |
476 | entry->hdr.uflags = 0; | |
7c9e7a6f AG |
477 | |
478 | UPDATE_HEAD(mb->cmd_head, pad_size, udev->cmdr_size); | |
479 | ||
480 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
481 | WARN_ON(cmd_head != 0); | |
482 | } | |
483 | ||
484 | entry = (void *) mb + CMDR_OFF + cmd_head; | |
485 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
0ad46af8 AG |
486 | tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_CMD); |
487 | tcmu_hdr_set_len(&entry->hdr.len_op, command_size); | |
488 | entry->hdr.cmd_id = tcmu_cmd->cmd_id; | |
489 | entry->hdr.kflags = 0; | |
490 | entry->hdr.uflags = 0; | |
7c9e7a6f | 491 | |
26418649 SY |
492 | bitmap_copy(old_bitmap, udev->data_bitmap, DATA_BLOCK_BITS); |
493 | ||
3d9b9555 | 494 | /* Handle allocating space from the data area */ |
7c9e7a6f | 495 | iov = &entry->req.iov[0]; |
f97ec7db | 496 | iov_cnt = 0; |
e4648b01 IT |
497 | copy_to_data_area = (se_cmd->data_direction == DMA_TO_DEVICE |
498 | || se_cmd->se_cmd_flags & SCF_BIDI); | |
f97ec7db IT |
499 | alloc_and_scatter_data_area(udev, se_cmd->t_data_sg, |
500 | se_cmd->t_data_nents, &iov, &iov_cnt, copy_to_data_area); | |
7c9e7a6f | 501 | entry->req.iov_cnt = iov_cnt; |
0ad46af8 | 502 | entry->req.iov_dif_cnt = 0; |
7c9e7a6f | 503 | |
e4648b01 IT |
504 | /* Handle BIDI commands */ |
505 | iov_cnt = 0; | |
506 | alloc_and_scatter_data_area(udev, se_cmd->t_bidi_data_sg, | |
507 | se_cmd->t_bidi_data_nents, &iov, &iov_cnt, false); | |
508 | entry->req.iov_bidi_cnt = iov_cnt; | |
509 | ||
26418649 SY |
510 | /* cmd's data_bitmap is what changed in process */ |
511 | bitmap_xor(tcmu_cmd->data_bitmap, old_bitmap, udev->data_bitmap, | |
512 | DATA_BLOCK_BITS); | |
513 | ||
7c9e7a6f AG |
514 | /* All offsets relative to mb_addr, not start of entry! */ |
515 | cdb_off = CMDR_OFF + cmd_head + base_command_size; | |
516 | memcpy((void *) mb + cdb_off, se_cmd->t_task_cdb, scsi_command_size(se_cmd->t_task_cdb)); | |
517 | entry->req.cdb_off = cdb_off; | |
518 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
519 | ||
520 | UPDATE_HEAD(mb->cmd_head, command_size, udev->cmdr_size); | |
521 | tcmu_flush_dcache_range(mb, sizeof(*mb)); | |
522 | ||
523 | spin_unlock_irq(&udev->cmdr_lock); | |
524 | ||
525 | /* TODO: only if FLUSH and FUA? */ | |
526 | uio_event_notify(&udev->uio_info); | |
527 | ||
528 | mod_timer(&udev->timeout, | |
529 | round_jiffies_up(jiffies + msecs_to_jiffies(TCMU_TIME_OUT))); | |
530 | ||
02eb924f | 531 | return TCM_NO_SENSE; |
7c9e7a6f AG |
532 | } |
533 | ||
02eb924f AG |
534 | static sense_reason_t |
535 | tcmu_queue_cmd(struct se_cmd *se_cmd) | |
7c9e7a6f AG |
536 | { |
537 | struct se_device *se_dev = se_cmd->se_dev; | |
538 | struct tcmu_dev *udev = TCMU_DEV(se_dev); | |
539 | struct tcmu_cmd *tcmu_cmd; | |
540 | int ret; | |
541 | ||
542 | tcmu_cmd = tcmu_alloc_cmd(se_cmd); | |
543 | if (!tcmu_cmd) | |
02eb924f | 544 | return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; |
7c9e7a6f AG |
545 | |
546 | ret = tcmu_queue_cmd_ring(tcmu_cmd); | |
02eb924f | 547 | if (ret != TCM_NO_SENSE) { |
7c9e7a6f AG |
548 | pr_err("TCMU: Could not queue command\n"); |
549 | spin_lock_irq(&udev->commands_lock); | |
550 | idr_remove(&udev->commands, tcmu_cmd->cmd_id); | |
551 | spin_unlock_irq(&udev->commands_lock); | |
552 | ||
553 | kmem_cache_free(tcmu_cmd_cache, tcmu_cmd); | |
554 | } | |
555 | ||
556 | return ret; | |
557 | } | |
558 | ||
559 | static void tcmu_handle_completion(struct tcmu_cmd *cmd, struct tcmu_cmd_entry *entry) | |
560 | { | |
561 | struct se_cmd *se_cmd = cmd->se_cmd; | |
562 | struct tcmu_dev *udev = cmd->tcmu_dev; | |
563 | ||
564 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) { | |
b25c7863 SY |
565 | /* |
566 | * cmd has been completed already from timeout, just reclaim | |
3d9b9555 | 567 | * data area space and free cmd |
b25c7863 | 568 | */ |
26418649 | 569 | free_data_area(udev, cmd); |
b25c7863 SY |
570 | |
571 | kmem_cache_free(tcmu_cmd_cache, cmd); | |
7c9e7a6f AG |
572 | return; |
573 | } | |
574 | ||
0ad46af8 | 575 | if (entry->hdr.uflags & TCMU_UFLAG_UNKNOWN_OP) { |
26418649 | 576 | free_data_area(udev, cmd); |
0ad46af8 AG |
577 | pr_warn("TCMU: Userspace set UNKNOWN_OP flag on se_cmd %p\n", |
578 | cmd->se_cmd); | |
ed97d0cd AG |
579 | entry->rsp.scsi_status = SAM_STAT_CHECK_CONDITION; |
580 | } else if (entry->rsp.scsi_status == SAM_STAT_CHECK_CONDITION) { | |
7c9e7a6f AG |
581 | memcpy(se_cmd->sense_buffer, entry->rsp.sense_buffer, |
582 | se_cmd->scsi_sense_length); | |
26418649 | 583 | free_data_area(udev, cmd); |
e4648b01 | 584 | } else if (se_cmd->se_cmd_flags & SCF_BIDI) { |
26418649 | 585 | DECLARE_BITMAP(bitmap, DATA_BLOCK_BITS); |
e4648b01 | 586 | |
26418649 SY |
587 | /* Get Data-In buffer before clean up */ |
588 | bitmap_copy(bitmap, cmd->data_bitmap, DATA_BLOCK_BITS); | |
589 | gather_data_area(udev, bitmap, | |
e4648b01 | 590 | se_cmd->t_bidi_data_sg, se_cmd->t_bidi_data_nents); |
26418649 | 591 | free_data_area(udev, cmd); |
e4648b01 | 592 | } else if (se_cmd->data_direction == DMA_FROM_DEVICE) { |
26418649 SY |
593 | DECLARE_BITMAP(bitmap, DATA_BLOCK_BITS); |
594 | ||
595 | bitmap_copy(bitmap, cmd->data_bitmap, DATA_BLOCK_BITS); | |
596 | gather_data_area(udev, bitmap, | |
f97ec7db | 597 | se_cmd->t_data_sg, se_cmd->t_data_nents); |
26418649 | 598 | free_data_area(udev, cmd); |
7c9e7a6f | 599 | } else if (se_cmd->data_direction == DMA_TO_DEVICE) { |
26418649 | 600 | free_data_area(udev, cmd); |
2bc396a2 IT |
601 | } else if (se_cmd->data_direction != DMA_NONE) { |
602 | pr_warn("TCMU: data direction was %d!\n", | |
603 | se_cmd->data_direction); | |
7c9e7a6f AG |
604 | } |
605 | ||
606 | target_complete_cmd(cmd->se_cmd, entry->rsp.scsi_status); | |
607 | cmd->se_cmd = NULL; | |
608 | ||
609 | kmem_cache_free(tcmu_cmd_cache, cmd); | |
610 | } | |
611 | ||
612 | static unsigned int tcmu_handle_completions(struct tcmu_dev *udev) | |
613 | { | |
614 | struct tcmu_mailbox *mb; | |
7c9e7a6f AG |
615 | unsigned long flags; |
616 | int handled = 0; | |
617 | ||
618 | if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) { | |
619 | pr_err("ring broken, not handling completions\n"); | |
620 | return 0; | |
621 | } | |
622 | ||
623 | spin_lock_irqsave(&udev->cmdr_lock, flags); | |
624 | ||
625 | mb = udev->mb_addr; | |
626 | tcmu_flush_dcache_range(mb, sizeof(*mb)); | |
627 | ||
628 | while (udev->cmdr_last_cleaned != ACCESS_ONCE(mb->cmd_tail)) { | |
629 | ||
630 | struct tcmu_cmd_entry *entry = (void *) mb + CMDR_OFF + udev->cmdr_last_cleaned; | |
631 | struct tcmu_cmd *cmd; | |
632 | ||
633 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
634 | ||
0ad46af8 AG |
635 | if (tcmu_hdr_get_op(entry->hdr.len_op) == TCMU_OP_PAD) { |
636 | UPDATE_HEAD(udev->cmdr_last_cleaned, | |
637 | tcmu_hdr_get_len(entry->hdr.len_op), | |
638 | udev->cmdr_size); | |
7c9e7a6f AG |
639 | continue; |
640 | } | |
0ad46af8 | 641 | WARN_ON(tcmu_hdr_get_op(entry->hdr.len_op) != TCMU_OP_CMD); |
7c9e7a6f AG |
642 | |
643 | spin_lock(&udev->commands_lock); | |
0ad46af8 | 644 | cmd = idr_find(&udev->commands, entry->hdr.cmd_id); |
7c9e7a6f AG |
645 | if (cmd) |
646 | idr_remove(&udev->commands, cmd->cmd_id); | |
647 | spin_unlock(&udev->commands_lock); | |
648 | ||
649 | if (!cmd) { | |
650 | pr_err("cmd_id not found, ring is broken\n"); | |
651 | set_bit(TCMU_DEV_BIT_BROKEN, &udev->flags); | |
652 | break; | |
653 | } | |
654 | ||
655 | tcmu_handle_completion(cmd, entry); | |
656 | ||
0ad46af8 AG |
657 | UPDATE_HEAD(udev->cmdr_last_cleaned, |
658 | tcmu_hdr_get_len(entry->hdr.len_op), | |
659 | udev->cmdr_size); | |
7c9e7a6f AG |
660 | |
661 | handled++; | |
662 | } | |
663 | ||
664 | if (mb->cmd_tail == mb->cmd_head) | |
665 | del_timer(&udev->timeout); /* no more pending cmds */ | |
666 | ||
667 | spin_unlock_irqrestore(&udev->cmdr_lock, flags); | |
668 | ||
669 | wake_up(&udev->wait_cmdr); | |
670 | ||
671 | return handled; | |
672 | } | |
673 | ||
674 | static int tcmu_check_expired_cmd(int id, void *p, void *data) | |
675 | { | |
676 | struct tcmu_cmd *cmd = p; | |
677 | ||
678 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) | |
679 | return 0; | |
680 | ||
611e2267 | 681 | if (!time_after(jiffies, cmd->deadline)) |
7c9e7a6f AG |
682 | return 0; |
683 | ||
684 | set_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags); | |
685 | target_complete_cmd(cmd->se_cmd, SAM_STAT_CHECK_CONDITION); | |
686 | cmd->se_cmd = NULL; | |
687 | ||
688 | kmem_cache_free(tcmu_cmd_cache, cmd); | |
689 | ||
690 | return 0; | |
691 | } | |
692 | ||
693 | static void tcmu_device_timedout(unsigned long data) | |
694 | { | |
695 | struct tcmu_dev *udev = (struct tcmu_dev *)data; | |
696 | unsigned long flags; | |
697 | int handled; | |
698 | ||
699 | handled = tcmu_handle_completions(udev); | |
700 | ||
701 | pr_warn("%d completions handled from timeout\n", handled); | |
702 | ||
703 | spin_lock_irqsave(&udev->commands_lock, flags); | |
704 | idr_for_each(&udev->commands, tcmu_check_expired_cmd, NULL); | |
705 | spin_unlock_irqrestore(&udev->commands_lock, flags); | |
706 | ||
707 | /* | |
708 | * We don't need to wakeup threads on wait_cmdr since they have their | |
709 | * own timeout. | |
710 | */ | |
711 | } | |
712 | ||
713 | static int tcmu_attach_hba(struct se_hba *hba, u32 host_id) | |
714 | { | |
715 | struct tcmu_hba *tcmu_hba; | |
716 | ||
717 | tcmu_hba = kzalloc(sizeof(struct tcmu_hba), GFP_KERNEL); | |
718 | if (!tcmu_hba) | |
719 | return -ENOMEM; | |
720 | ||
721 | tcmu_hba->host_id = host_id; | |
722 | hba->hba_ptr = tcmu_hba; | |
723 | ||
724 | return 0; | |
725 | } | |
726 | ||
727 | static void tcmu_detach_hba(struct se_hba *hba) | |
728 | { | |
729 | kfree(hba->hba_ptr); | |
730 | hba->hba_ptr = NULL; | |
731 | } | |
732 | ||
733 | static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name) | |
734 | { | |
735 | struct tcmu_dev *udev; | |
736 | ||
737 | udev = kzalloc(sizeof(struct tcmu_dev), GFP_KERNEL); | |
738 | if (!udev) | |
739 | return NULL; | |
740 | ||
741 | udev->name = kstrdup(name, GFP_KERNEL); | |
742 | if (!udev->name) { | |
743 | kfree(udev); | |
744 | return NULL; | |
745 | } | |
746 | ||
747 | udev->hba = hba; | |
748 | ||
749 | init_waitqueue_head(&udev->wait_cmdr); | |
750 | spin_lock_init(&udev->cmdr_lock); | |
751 | ||
752 | idr_init(&udev->commands); | |
753 | spin_lock_init(&udev->commands_lock); | |
754 | ||
755 | setup_timer(&udev->timeout, tcmu_device_timedout, | |
756 | (unsigned long)udev); | |
757 | ||
7c9e7a6f AG |
758 | return &udev->se_dev; |
759 | } | |
760 | ||
761 | static int tcmu_irqcontrol(struct uio_info *info, s32 irq_on) | |
762 | { | |
763 | struct tcmu_dev *tcmu_dev = container_of(info, struct tcmu_dev, uio_info); | |
764 | ||
765 | tcmu_handle_completions(tcmu_dev); | |
766 | ||
767 | return 0; | |
768 | } | |
769 | ||
770 | /* | |
771 | * mmap code from uio.c. Copied here because we want to hook mmap() | |
772 | * and this stuff must come along. | |
773 | */ | |
774 | static int tcmu_find_mem_index(struct vm_area_struct *vma) | |
775 | { | |
776 | struct tcmu_dev *udev = vma->vm_private_data; | |
777 | struct uio_info *info = &udev->uio_info; | |
778 | ||
779 | if (vma->vm_pgoff < MAX_UIO_MAPS) { | |
780 | if (info->mem[vma->vm_pgoff].size == 0) | |
781 | return -1; | |
782 | return (int)vma->vm_pgoff; | |
783 | } | |
784 | return -1; | |
785 | } | |
786 | ||
787 | static int tcmu_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf) | |
788 | { | |
789 | struct tcmu_dev *udev = vma->vm_private_data; | |
790 | struct uio_info *info = &udev->uio_info; | |
791 | struct page *page; | |
792 | unsigned long offset; | |
793 | void *addr; | |
794 | ||
795 | int mi = tcmu_find_mem_index(vma); | |
796 | if (mi < 0) | |
797 | return VM_FAULT_SIGBUS; | |
798 | ||
799 | /* | |
800 | * We need to subtract mi because userspace uses offset = N*PAGE_SIZE | |
801 | * to use mem[N]. | |
802 | */ | |
803 | offset = (vmf->pgoff - mi) << PAGE_SHIFT; | |
804 | ||
805 | addr = (void *)(unsigned long)info->mem[mi].addr + offset; | |
806 | if (info->mem[mi].memtype == UIO_MEM_LOGICAL) | |
807 | page = virt_to_page(addr); | |
808 | else | |
809 | page = vmalloc_to_page(addr); | |
810 | get_page(page); | |
811 | vmf->page = page; | |
812 | return 0; | |
813 | } | |
814 | ||
815 | static const struct vm_operations_struct tcmu_vm_ops = { | |
816 | .fault = tcmu_vma_fault, | |
817 | }; | |
818 | ||
819 | static int tcmu_mmap(struct uio_info *info, struct vm_area_struct *vma) | |
820 | { | |
821 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); | |
822 | ||
823 | vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; | |
824 | vma->vm_ops = &tcmu_vm_ops; | |
825 | ||
826 | vma->vm_private_data = udev; | |
827 | ||
828 | /* Ensure the mmap is exactly the right size */ | |
829 | if (vma_pages(vma) != (TCMU_RING_SIZE >> PAGE_SHIFT)) | |
830 | return -EINVAL; | |
831 | ||
832 | return 0; | |
833 | } | |
834 | ||
835 | static int tcmu_open(struct uio_info *info, struct inode *inode) | |
836 | { | |
837 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); | |
838 | ||
839 | /* O_EXCL not supported for char devs, so fake it? */ | |
840 | if (test_and_set_bit(TCMU_DEV_BIT_OPEN, &udev->flags)) | |
841 | return -EBUSY; | |
842 | ||
843 | pr_debug("open\n"); | |
844 | ||
845 | return 0; | |
846 | } | |
847 | ||
848 | static int tcmu_release(struct uio_info *info, struct inode *inode) | |
849 | { | |
850 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); | |
851 | ||
852 | clear_bit(TCMU_DEV_BIT_OPEN, &udev->flags); | |
853 | ||
854 | pr_debug("close\n"); | |
855 | ||
856 | return 0; | |
857 | } | |
858 | ||
859 | static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name, int minor) | |
860 | { | |
861 | struct sk_buff *skb; | |
862 | void *msg_header; | |
6e14eab9 | 863 | int ret = -ENOMEM; |
7c9e7a6f AG |
864 | |
865 | skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); | |
866 | if (!skb) | |
6e14eab9 | 867 | return ret; |
7c9e7a6f AG |
868 | |
869 | msg_header = genlmsg_put(skb, 0, 0, &tcmu_genl_family, 0, cmd); | |
6e14eab9 NB |
870 | if (!msg_header) |
871 | goto free_skb; | |
7c9e7a6f AG |
872 | |
873 | ret = nla_put_string(skb, TCMU_ATTR_DEVICE, name); | |
6e14eab9 NB |
874 | if (ret < 0) |
875 | goto free_skb; | |
7c9e7a6f AG |
876 | |
877 | ret = nla_put_u32(skb, TCMU_ATTR_MINOR, minor); | |
6e14eab9 NB |
878 | if (ret < 0) |
879 | goto free_skb; | |
7c9e7a6f | 880 | |
053c095a | 881 | genlmsg_end(skb, msg_header); |
7c9e7a6f | 882 | |
20c08b36 | 883 | ret = genlmsg_multicast_allns(&tcmu_genl_family, skb, 0, |
7c9e7a6f AG |
884 | TCMU_MCGRP_CONFIG, GFP_KERNEL); |
885 | ||
886 | /* We don't care if no one is listening */ | |
887 | if (ret == -ESRCH) | |
888 | ret = 0; | |
889 | ||
890 | return ret; | |
6e14eab9 NB |
891 | free_skb: |
892 | nlmsg_free(skb); | |
893 | return ret; | |
7c9e7a6f AG |
894 | } |
895 | ||
896 | static int tcmu_configure_device(struct se_device *dev) | |
897 | { | |
898 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
899 | struct tcmu_hba *hba = udev->hba->hba_ptr; | |
900 | struct uio_info *info; | |
901 | struct tcmu_mailbox *mb; | |
902 | size_t size; | |
903 | size_t used; | |
904 | int ret = 0; | |
905 | char *str; | |
906 | ||
907 | info = &udev->uio_info; | |
908 | ||
909 | size = snprintf(NULL, 0, "tcm-user/%u/%s/%s", hba->host_id, udev->name, | |
910 | udev->dev_config); | |
911 | size += 1; /* for \0 */ | |
912 | str = kmalloc(size, GFP_KERNEL); | |
913 | if (!str) | |
914 | return -ENOMEM; | |
915 | ||
916 | used = snprintf(str, size, "tcm-user/%u/%s", hba->host_id, udev->name); | |
917 | ||
918 | if (udev->dev_config[0]) | |
919 | snprintf(str + used, size - used, "/%s", udev->dev_config); | |
920 | ||
921 | info->name = str; | |
922 | ||
923 | udev->mb_addr = vzalloc(TCMU_RING_SIZE); | |
924 | if (!udev->mb_addr) { | |
925 | ret = -ENOMEM; | |
926 | goto err_vzalloc; | |
927 | } | |
928 | ||
929 | /* mailbox fits in first part of CMDR space */ | |
930 | udev->cmdr_size = CMDR_SIZE - CMDR_OFF; | |
931 | udev->data_off = CMDR_SIZE; | |
932 | udev->data_size = TCMU_RING_SIZE - CMDR_SIZE; | |
933 | ||
934 | mb = udev->mb_addr; | |
0ad46af8 | 935 | mb->version = TCMU_MAILBOX_VERSION; |
32c76de3 | 936 | mb->flags = TCMU_MAILBOX_FLAG_CAP_OOOC; |
7c9e7a6f AG |
937 | mb->cmdr_off = CMDR_OFF; |
938 | mb->cmdr_size = udev->cmdr_size; | |
939 | ||
940 | WARN_ON(!PAGE_ALIGNED(udev->data_off)); | |
941 | WARN_ON(udev->data_size % PAGE_SIZE); | |
26418649 | 942 | WARN_ON(udev->data_size % DATA_BLOCK_SIZE); |
7c9e7a6f | 943 | |
ac64a2ce | 944 | info->version = __stringify(TCMU_MAILBOX_VERSION); |
7c9e7a6f AG |
945 | |
946 | info->mem[0].name = "tcm-user command & data buffer"; | |
0633e123 | 947 | info->mem[0].addr = (phys_addr_t)(uintptr_t)udev->mb_addr; |
7c9e7a6f AG |
948 | info->mem[0].size = TCMU_RING_SIZE; |
949 | info->mem[0].memtype = UIO_MEM_VIRTUAL; | |
950 | ||
951 | info->irqcontrol = tcmu_irqcontrol; | |
952 | info->irq = UIO_IRQ_CUSTOM; | |
953 | ||
954 | info->mmap = tcmu_mmap; | |
955 | info->open = tcmu_open; | |
956 | info->release = tcmu_release; | |
957 | ||
958 | ret = uio_register_device(tcmu_root_device, info); | |
959 | if (ret) | |
960 | goto err_register; | |
961 | ||
81ee28de SY |
962 | /* User can set hw_block_size before enable the device */ |
963 | if (dev->dev_attrib.hw_block_size == 0) | |
964 | dev->dev_attrib.hw_block_size = 512; | |
7c9e7a6f | 965 | /* Other attributes can be configured in userspace */ |
7c9e7a6f AG |
966 | dev->dev_attrib.hw_max_sectors = 128; |
967 | dev->dev_attrib.hw_queue_depth = 128; | |
968 | ||
969 | ret = tcmu_netlink_event(TCMU_CMD_ADDED_DEVICE, udev->uio_info.name, | |
970 | udev->uio_info.uio_dev->minor); | |
971 | if (ret) | |
972 | goto err_netlink; | |
973 | ||
974 | return 0; | |
975 | ||
976 | err_netlink: | |
977 | uio_unregister_device(&udev->uio_info); | |
978 | err_register: | |
979 | vfree(udev->mb_addr); | |
980 | err_vzalloc: | |
981 | kfree(info->name); | |
982 | ||
983 | return ret; | |
984 | } | |
985 | ||
b25c7863 | 986 | static int tcmu_check_and_free_pending_cmd(struct tcmu_cmd *cmd) |
7c9e7a6f | 987 | { |
b25c7863 SY |
988 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) { |
989 | kmem_cache_free(tcmu_cmd_cache, cmd); | |
7c9e7a6f | 990 | return 0; |
b25c7863 | 991 | } |
7c9e7a6f AG |
992 | return -EINVAL; |
993 | } | |
994 | ||
4cc987ea NB |
995 | static void tcmu_dev_call_rcu(struct rcu_head *p) |
996 | { | |
997 | struct se_device *dev = container_of(p, struct se_device, rcu_head); | |
998 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
999 | ||
1000 | kfree(udev); | |
1001 | } | |
1002 | ||
7c9e7a6f AG |
1003 | static void tcmu_free_device(struct se_device *dev) |
1004 | { | |
1005 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
b25c7863 SY |
1006 | struct tcmu_cmd *cmd; |
1007 | bool all_expired = true; | |
7c9e7a6f AG |
1008 | int i; |
1009 | ||
1010 | del_timer_sync(&udev->timeout); | |
1011 | ||
1012 | vfree(udev->mb_addr); | |
1013 | ||
1014 | /* Upper layer should drain all requests before calling this */ | |
1015 | spin_lock_irq(&udev->commands_lock); | |
b25c7863 SY |
1016 | idr_for_each_entry(&udev->commands, cmd, i) { |
1017 | if (tcmu_check_and_free_pending_cmd(cmd) != 0) | |
1018 | all_expired = false; | |
1019 | } | |
7c9e7a6f AG |
1020 | idr_destroy(&udev->commands); |
1021 | spin_unlock_irq(&udev->commands_lock); | |
b25c7863 | 1022 | WARN_ON(!all_expired); |
7c9e7a6f AG |
1023 | |
1024 | /* Device was configured */ | |
1025 | if (udev->uio_info.uio_dev) { | |
1026 | tcmu_netlink_event(TCMU_CMD_REMOVED_DEVICE, udev->uio_info.name, | |
1027 | udev->uio_info.uio_dev->minor); | |
1028 | ||
1029 | uio_unregister_device(&udev->uio_info); | |
1030 | kfree(udev->uio_info.name); | |
1031 | kfree(udev->name); | |
1032 | } | |
4cc987ea | 1033 | call_rcu(&dev->rcu_head, tcmu_dev_call_rcu); |
7c9e7a6f AG |
1034 | } |
1035 | ||
1036 | enum { | |
9c1cd1b6 | 1037 | Opt_dev_config, Opt_dev_size, Opt_hw_block_size, Opt_err, |
7c9e7a6f AG |
1038 | }; |
1039 | ||
1040 | static match_table_t tokens = { | |
1041 | {Opt_dev_config, "dev_config=%s"}, | |
1042 | {Opt_dev_size, "dev_size=%u"}, | |
9c1cd1b6 | 1043 | {Opt_hw_block_size, "hw_block_size=%u"}, |
7c9e7a6f AG |
1044 | {Opt_err, NULL} |
1045 | }; | |
1046 | ||
1047 | static ssize_t tcmu_set_configfs_dev_params(struct se_device *dev, | |
1048 | const char *page, ssize_t count) | |
1049 | { | |
1050 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
1051 | char *orig, *ptr, *opts, *arg_p; | |
1052 | substring_t args[MAX_OPT_ARGS]; | |
1053 | int ret = 0, token; | |
9c1cd1b6 | 1054 | unsigned long tmp_ul; |
7c9e7a6f AG |
1055 | |
1056 | opts = kstrdup(page, GFP_KERNEL); | |
1057 | if (!opts) | |
1058 | return -ENOMEM; | |
1059 | ||
1060 | orig = opts; | |
1061 | ||
1062 | while ((ptr = strsep(&opts, ",\n")) != NULL) { | |
1063 | if (!*ptr) | |
1064 | continue; | |
1065 | ||
1066 | token = match_token(ptr, tokens, args); | |
1067 | switch (token) { | |
1068 | case Opt_dev_config: | |
1069 | if (match_strlcpy(udev->dev_config, &args[0], | |
1070 | TCMU_CONFIG_LEN) == 0) { | |
1071 | ret = -EINVAL; | |
1072 | break; | |
1073 | } | |
1074 | pr_debug("TCMU: Referencing Path: %s\n", udev->dev_config); | |
1075 | break; | |
1076 | case Opt_dev_size: | |
1077 | arg_p = match_strdup(&args[0]); | |
1078 | if (!arg_p) { | |
1079 | ret = -ENOMEM; | |
1080 | break; | |
1081 | } | |
1082 | ret = kstrtoul(arg_p, 0, (unsigned long *) &udev->dev_size); | |
1083 | kfree(arg_p); | |
1084 | if (ret < 0) | |
1085 | pr_err("kstrtoul() failed for dev_size=\n"); | |
1086 | break; | |
9c1cd1b6 AG |
1087 | case Opt_hw_block_size: |
1088 | arg_p = match_strdup(&args[0]); | |
1089 | if (!arg_p) { | |
1090 | ret = -ENOMEM; | |
1091 | break; | |
1092 | } | |
1093 | ret = kstrtoul(arg_p, 0, &tmp_ul); | |
1094 | kfree(arg_p); | |
1095 | if (ret < 0) { | |
1096 | pr_err("kstrtoul() failed for hw_block_size=\n"); | |
1097 | break; | |
1098 | } | |
1099 | if (!tmp_ul) { | |
1100 | pr_err("hw_block_size must be nonzero\n"); | |
1101 | break; | |
1102 | } | |
1103 | dev->dev_attrib.hw_block_size = tmp_ul; | |
1104 | break; | |
7c9e7a6f AG |
1105 | default: |
1106 | break; | |
1107 | } | |
1108 | } | |
1109 | ||
1110 | kfree(orig); | |
1111 | return (!ret) ? count : ret; | |
1112 | } | |
1113 | ||
1114 | static ssize_t tcmu_show_configfs_dev_params(struct se_device *dev, char *b) | |
1115 | { | |
1116 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
1117 | ssize_t bl = 0; | |
1118 | ||
1119 | bl = sprintf(b + bl, "Config: %s ", | |
1120 | udev->dev_config[0] ? udev->dev_config : "NULL"); | |
8ee83a74 | 1121 | bl += sprintf(b + bl, "Size: %zu\n", udev->dev_size); |
7c9e7a6f AG |
1122 | |
1123 | return bl; | |
1124 | } | |
1125 | ||
1126 | static sector_t tcmu_get_blocks(struct se_device *dev) | |
1127 | { | |
1128 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
1129 | ||
1130 | return div_u64(udev->dev_size - dev->dev_attrib.block_size, | |
1131 | dev->dev_attrib.block_size); | |
1132 | } | |
1133 | ||
7c9e7a6f | 1134 | static sense_reason_t |
9c1cd1b6 | 1135 | tcmu_parse_cdb(struct se_cmd *cmd) |
7c9e7a6f | 1136 | { |
02eb924f | 1137 | return passthrough_parse_cdb(cmd, tcmu_queue_cmd); |
7c9e7a6f AG |
1138 | } |
1139 | ||
0a06d430 | 1140 | static const struct target_backend_ops tcmu_ops = { |
7c9e7a6f | 1141 | .name = "user", |
7c9e7a6f | 1142 | .owner = THIS_MODULE, |
a3541703 | 1143 | .transport_flags = TRANSPORT_FLAG_PASSTHROUGH, |
7c9e7a6f AG |
1144 | .attach_hba = tcmu_attach_hba, |
1145 | .detach_hba = tcmu_detach_hba, | |
1146 | .alloc_device = tcmu_alloc_device, | |
1147 | .configure_device = tcmu_configure_device, | |
1148 | .free_device = tcmu_free_device, | |
1149 | .parse_cdb = tcmu_parse_cdb, | |
1150 | .set_configfs_dev_params = tcmu_set_configfs_dev_params, | |
1151 | .show_configfs_dev_params = tcmu_show_configfs_dev_params, | |
1152 | .get_device_type = sbc_get_device_type, | |
1153 | .get_blocks = tcmu_get_blocks, | |
5873c4d1 | 1154 | .tb_dev_attrib_attrs = passthrough_attrib_attrs, |
7c9e7a6f AG |
1155 | }; |
1156 | ||
1157 | static int __init tcmu_module_init(void) | |
1158 | { | |
1159 | int ret; | |
1160 | ||
1161 | BUILD_BUG_ON((sizeof(struct tcmu_cmd_entry) % TCMU_OP_ALIGN_SIZE) != 0); | |
1162 | ||
1163 | tcmu_cmd_cache = kmem_cache_create("tcmu_cmd_cache", | |
1164 | sizeof(struct tcmu_cmd), | |
1165 | __alignof__(struct tcmu_cmd), | |
1166 | 0, NULL); | |
1167 | if (!tcmu_cmd_cache) | |
1168 | return -ENOMEM; | |
1169 | ||
1170 | tcmu_root_device = root_device_register("tcm_user"); | |
1171 | if (IS_ERR(tcmu_root_device)) { | |
1172 | ret = PTR_ERR(tcmu_root_device); | |
1173 | goto out_free_cache; | |
1174 | } | |
1175 | ||
1176 | ret = genl_register_family(&tcmu_genl_family); | |
1177 | if (ret < 0) { | |
1178 | goto out_unreg_device; | |
1179 | } | |
1180 | ||
0a06d430 | 1181 | ret = transport_backend_register(&tcmu_ops); |
7c9e7a6f AG |
1182 | if (ret) |
1183 | goto out_unreg_genl; | |
1184 | ||
1185 | return 0; | |
1186 | ||
1187 | out_unreg_genl: | |
1188 | genl_unregister_family(&tcmu_genl_family); | |
1189 | out_unreg_device: | |
1190 | root_device_unregister(tcmu_root_device); | |
1191 | out_free_cache: | |
1192 | kmem_cache_destroy(tcmu_cmd_cache); | |
1193 | ||
1194 | return ret; | |
1195 | } | |
1196 | ||
1197 | static void __exit tcmu_module_exit(void) | |
1198 | { | |
0a06d430 | 1199 | target_backend_unregister(&tcmu_ops); |
7c9e7a6f AG |
1200 | genl_unregister_family(&tcmu_genl_family); |
1201 | root_device_unregister(tcmu_root_device); | |
1202 | kmem_cache_destroy(tcmu_cmd_cache); | |
1203 | } | |
1204 | ||
1205 | MODULE_DESCRIPTION("TCM USER subsystem plugin"); | |
1206 | MODULE_AUTHOR("Shaohua Li <shli@kernel.org>"); | |
1207 | MODULE_AUTHOR("Andy Grover <agrover@redhat.com>"); | |
1208 | MODULE_LICENSE("GPL"); | |
1209 | ||
1210 | module_init(tcmu_module_init); | |
1211 | module_exit(tcmu_module_exit); |