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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> |
26418649 | 29 | #include <linux/bitops.h> |
f5045724 | 30 | #include <linux/highmem.h> |
7c9e7a6f | 31 | #include <net/genetlink.h> |
ba929992 BVA |
32 | #include <scsi/scsi_common.h> |
33 | #include <scsi/scsi_proto.h> | |
7c9e7a6f AG |
34 | #include <target/target_core_base.h> |
35 | #include <target/target_core_fabric.h> | |
36 | #include <target/target_core_backend.h> | |
e9f720d6 | 37 | |
7c9e7a6f AG |
38 | #include <linux/target_core_user.h> |
39 | ||
40 | /* | |
41 | * Define a shared-memory interface for LIO to pass SCSI commands and | |
42 | * data to userspace for processing. This is to allow backends that | |
43 | * are too complex for in-kernel support to be possible. | |
44 | * | |
45 | * It uses the UIO framework to do a lot of the device-creation and | |
46 | * introspection work for us. | |
47 | * | |
48 | * See the .h file for how the ring is laid out. Note that while the | |
49 | * command ring is defined, the particulars of the data area are | |
50 | * not. Offset values in the command entry point to other locations | |
51 | * internal to the mmap()ed area. There is separate space outside the | |
52 | * command ring for data buffers. This leaves maximum flexibility for | |
53 | * moving buffer allocations, or even page flipping or other | |
54 | * allocation techniques, without altering the command ring layout. | |
55 | * | |
56 | * SECURITY: | |
57 | * The user process must be assumed to be malicious. There's no way to | |
58 | * prevent it breaking the command ring protocol if it wants, but in | |
59 | * order to prevent other issues we must only ever read *data* from | |
60 | * the shared memory area, not offsets or sizes. This applies to | |
61 | * command ring entries as well as the mailbox. Extra code needed for | |
62 | * this may have a 'UAM' comment. | |
63 | */ | |
64 | ||
65 | ||
66 | #define TCMU_TIME_OUT (30 * MSEC_PER_SEC) | |
67 | ||
26418649 SY |
68 | #define DATA_BLOCK_BITS 256 |
69 | #define DATA_BLOCK_SIZE 4096 | |
70 | ||
7c9e7a6f | 71 | #define CMDR_SIZE (16 * 4096) |
26418649 | 72 | #define DATA_SIZE (DATA_BLOCK_BITS * DATA_BLOCK_SIZE) |
7c9e7a6f AG |
73 | |
74 | #define TCMU_RING_SIZE (CMDR_SIZE + DATA_SIZE) | |
75 | ||
76 | static struct device *tcmu_root_device; | |
77 | ||
78 | struct tcmu_hba { | |
79 | u32 host_id; | |
80 | }; | |
81 | ||
7c9e7a6f AG |
82 | #define TCMU_CONFIG_LEN 256 |
83 | ||
84 | struct tcmu_dev { | |
85 | struct se_device se_dev; | |
86 | ||
87 | char *name; | |
88 | struct se_hba *hba; | |
89 | ||
90 | #define TCMU_DEV_BIT_OPEN 0 | |
91 | #define TCMU_DEV_BIT_BROKEN 1 | |
92 | unsigned long flags; | |
7c9e7a6f AG |
93 | |
94 | struct uio_info uio_info; | |
95 | ||
96 | struct tcmu_mailbox *mb_addr; | |
97 | size_t dev_size; | |
98 | u32 cmdr_size; | |
99 | u32 cmdr_last_cleaned; | |
3d9b9555 | 100 | /* Offset of data area from start of mb */ |
26418649 | 101 | /* Must add data_off and mb_addr to get the address */ |
7c9e7a6f AG |
102 | size_t data_off; |
103 | size_t data_size; | |
26418649 SY |
104 | |
105 | DECLARE_BITMAP(data_bitmap, DATA_BLOCK_BITS); | |
7c9e7a6f AG |
106 | |
107 | wait_queue_head_t wait_cmdr; | |
108 | /* TODO should this be a mutex? */ | |
109 | spinlock_t cmdr_lock; | |
110 | ||
111 | struct idr commands; | |
112 | spinlock_t commands_lock; | |
113 | ||
114 | struct timer_list timeout; | |
115 | ||
116 | char dev_config[TCMU_CONFIG_LEN]; | |
117 | }; | |
118 | ||
119 | #define TCMU_DEV(_se_dev) container_of(_se_dev, struct tcmu_dev, se_dev) | |
120 | ||
121 | #define CMDR_OFF sizeof(struct tcmu_mailbox) | |
122 | ||
123 | struct tcmu_cmd { | |
124 | struct se_cmd *se_cmd; | |
125 | struct tcmu_dev *tcmu_dev; | |
126 | ||
127 | uint16_t cmd_id; | |
128 | ||
26418649 | 129 | /* Can't use se_cmd when cleaning up expired cmds, because if |
7c9e7a6f | 130 | cmd has been completed then accessing se_cmd is off limits */ |
26418649 | 131 | DECLARE_BITMAP(data_bitmap, DATA_BLOCK_BITS); |
7c9e7a6f AG |
132 | |
133 | unsigned long deadline; | |
134 | ||
135 | #define TCMU_CMD_BIT_EXPIRED 0 | |
136 | unsigned long flags; | |
137 | }; | |
138 | ||
139 | static struct kmem_cache *tcmu_cmd_cache; | |
140 | ||
141 | /* multicast group */ | |
142 | enum tcmu_multicast_groups { | |
143 | TCMU_MCGRP_CONFIG, | |
144 | }; | |
145 | ||
146 | static const struct genl_multicast_group tcmu_mcgrps[] = { | |
147 | [TCMU_MCGRP_CONFIG] = { .name = "config", }, | |
148 | }; | |
149 | ||
150 | /* Our generic netlink family */ | |
56989f6d | 151 | static struct genl_family tcmu_genl_family __ro_after_init = { |
489111e5 | 152 | .module = THIS_MODULE, |
7c9e7a6f AG |
153 | .hdrsize = 0, |
154 | .name = "TCM-USER", | |
155 | .version = 1, | |
156 | .maxattr = TCMU_ATTR_MAX, | |
157 | .mcgrps = tcmu_mcgrps, | |
158 | .n_mcgrps = ARRAY_SIZE(tcmu_mcgrps), | |
20c08b36 | 159 | .netnsok = true, |
7c9e7a6f AG |
160 | }; |
161 | ||
162 | static struct tcmu_cmd *tcmu_alloc_cmd(struct se_cmd *se_cmd) | |
163 | { | |
164 | struct se_device *se_dev = se_cmd->se_dev; | |
165 | struct tcmu_dev *udev = TCMU_DEV(se_dev); | |
166 | struct tcmu_cmd *tcmu_cmd; | |
167 | int cmd_id; | |
168 | ||
169 | tcmu_cmd = kmem_cache_zalloc(tcmu_cmd_cache, GFP_KERNEL); | |
170 | if (!tcmu_cmd) | |
171 | return NULL; | |
172 | ||
173 | tcmu_cmd->se_cmd = se_cmd; | |
174 | tcmu_cmd->tcmu_dev = udev; | |
7c9e7a6f AG |
175 | tcmu_cmd->deadline = jiffies + msecs_to_jiffies(TCMU_TIME_OUT); |
176 | ||
177 | idr_preload(GFP_KERNEL); | |
178 | spin_lock_irq(&udev->commands_lock); | |
179 | cmd_id = idr_alloc(&udev->commands, tcmu_cmd, 0, | |
180 | USHRT_MAX, GFP_NOWAIT); | |
181 | spin_unlock_irq(&udev->commands_lock); | |
182 | idr_preload_end(); | |
183 | ||
184 | if (cmd_id < 0) { | |
185 | kmem_cache_free(tcmu_cmd_cache, tcmu_cmd); | |
186 | return NULL; | |
187 | } | |
188 | tcmu_cmd->cmd_id = cmd_id; | |
189 | ||
190 | return tcmu_cmd; | |
191 | } | |
192 | ||
193 | static inline void tcmu_flush_dcache_range(void *vaddr, size_t size) | |
194 | { | |
b75d8063 | 195 | unsigned long offset = offset_in_page(vaddr); |
7c9e7a6f AG |
196 | |
197 | size = round_up(size+offset, PAGE_SIZE); | |
198 | vaddr -= offset; | |
199 | ||
200 | while (size) { | |
201 | flush_dcache_page(virt_to_page(vaddr)); | |
202 | size -= PAGE_SIZE; | |
203 | } | |
204 | } | |
205 | ||
206 | /* | |
207 | * Some ring helper functions. We don't assume size is a power of 2 so | |
208 | * we can't use circ_buf.h. | |
209 | */ | |
210 | static inline size_t spc_used(size_t head, size_t tail, size_t size) | |
211 | { | |
212 | int diff = head - tail; | |
213 | ||
214 | if (diff >= 0) | |
215 | return diff; | |
216 | else | |
217 | return size + diff; | |
218 | } | |
219 | ||
220 | static inline size_t spc_free(size_t head, size_t tail, size_t size) | |
221 | { | |
222 | /* Keep 1 byte unused or we can't tell full from empty */ | |
223 | return (size - spc_used(head, tail, size) - 1); | |
224 | } | |
225 | ||
226 | static inline size_t head_to_end(size_t head, size_t size) | |
227 | { | |
228 | return size - head; | |
229 | } | |
230 | ||
f1dbd087 SY |
231 | static inline void new_iov(struct iovec **iov, int *iov_cnt, |
232 | struct tcmu_dev *udev) | |
233 | { | |
234 | struct iovec *iovec; | |
235 | ||
236 | if (*iov_cnt != 0) | |
237 | (*iov)++; | |
238 | (*iov_cnt)++; | |
239 | ||
240 | iovec = *iov; | |
241 | memset(iovec, 0, sizeof(struct iovec)); | |
f1dbd087 SY |
242 | } |
243 | ||
7c9e7a6f AG |
244 | #define UPDATE_HEAD(head, used, size) smp_store_release(&head, ((head % size) + used) % size) |
245 | ||
26418649 SY |
246 | /* offset is relative to mb_addr */ |
247 | static inline size_t get_block_offset(struct tcmu_dev *dev, | |
248 | int block, int remaining) | |
249 | { | |
250 | return dev->data_off + block * DATA_BLOCK_SIZE + | |
251 | DATA_BLOCK_SIZE - remaining; | |
252 | } | |
253 | ||
254 | static inline size_t iov_tail(struct tcmu_dev *udev, struct iovec *iov) | |
255 | { | |
256 | return (size_t)iov->iov_base + iov->iov_len; | |
257 | } | |
258 | ||
f97ec7db IT |
259 | static void alloc_and_scatter_data_area(struct tcmu_dev *udev, |
260 | struct scatterlist *data_sg, unsigned int data_nents, | |
261 | struct iovec **iov, int *iov_cnt, bool copy_data) | |
262 | { | |
26418649 SY |
263 | int i, block; |
264 | int block_remaining = 0; | |
f97ec7db | 265 | void *from, *to; |
26418649 | 266 | size_t copy_bytes, to_offset; |
f97ec7db IT |
267 | struct scatterlist *sg; |
268 | ||
269 | for_each_sg(data_sg, sg, data_nents, i) { | |
26418649 | 270 | int sg_remaining = sg->length; |
f97ec7db | 271 | from = kmap_atomic(sg_page(sg)) + sg->offset; |
26418649 SY |
272 | while (sg_remaining > 0) { |
273 | if (block_remaining == 0) { | |
274 | block = find_first_zero_bit(udev->data_bitmap, | |
275 | DATA_BLOCK_BITS); | |
276 | block_remaining = DATA_BLOCK_SIZE; | |
277 | set_bit(block, udev->data_bitmap); | |
278 | } | |
279 | copy_bytes = min_t(size_t, sg_remaining, | |
280 | block_remaining); | |
281 | to_offset = get_block_offset(udev, block, | |
282 | block_remaining); | |
283 | to = (void *)udev->mb_addr + to_offset; | |
284 | if (*iov_cnt != 0 && | |
285 | to_offset == iov_tail(udev, *iov)) { | |
286 | (*iov)->iov_len += copy_bytes; | |
287 | } else { | |
288 | new_iov(iov, iov_cnt, udev); | |
289 | (*iov)->iov_base = (void __user *) to_offset; | |
290 | (*iov)->iov_len = copy_bytes; | |
291 | } | |
f97ec7db | 292 | if (copy_data) { |
26418649 SY |
293 | memcpy(to, from + sg->length - sg_remaining, |
294 | copy_bytes); | |
f97ec7db IT |
295 | tcmu_flush_dcache_range(to, copy_bytes); |
296 | } | |
26418649 SY |
297 | sg_remaining -= copy_bytes; |
298 | block_remaining -= copy_bytes; | |
f97ec7db | 299 | } |
e2e21bd8 | 300 | kunmap_atomic(from - sg->offset); |
f97ec7db IT |
301 | } |
302 | } | |
303 | ||
26418649 | 304 | static void free_data_area(struct tcmu_dev *udev, struct tcmu_cmd *cmd) |
0c28481f | 305 | { |
26418649 SY |
306 | bitmap_xor(udev->data_bitmap, udev->data_bitmap, cmd->data_bitmap, |
307 | DATA_BLOCK_BITS); | |
0c28481f SY |
308 | } |
309 | ||
26418649 SY |
310 | static void gather_data_area(struct tcmu_dev *udev, unsigned long *cmd_bitmap, |
311 | struct scatterlist *data_sg, unsigned int data_nents) | |
f97ec7db | 312 | { |
26418649 SY |
313 | int i, block; |
314 | int block_remaining = 0; | |
f97ec7db | 315 | void *from, *to; |
26418649 | 316 | size_t copy_bytes, from_offset; |
f97ec7db IT |
317 | struct scatterlist *sg; |
318 | ||
f97ec7db | 319 | for_each_sg(data_sg, sg, data_nents, i) { |
26418649 | 320 | int sg_remaining = sg->length; |
f97ec7db | 321 | to = kmap_atomic(sg_page(sg)) + sg->offset; |
26418649 SY |
322 | while (sg_remaining > 0) { |
323 | if (block_remaining == 0) { | |
324 | block = find_first_bit(cmd_bitmap, | |
325 | DATA_BLOCK_BITS); | |
326 | block_remaining = DATA_BLOCK_SIZE; | |
327 | clear_bit(block, cmd_bitmap); | |
328 | } | |
329 | copy_bytes = min_t(size_t, sg_remaining, | |
330 | block_remaining); | |
331 | from_offset = get_block_offset(udev, block, | |
332 | block_remaining); | |
333 | from = (void *) udev->mb_addr + from_offset; | |
f97ec7db | 334 | tcmu_flush_dcache_range(from, copy_bytes); |
26418649 SY |
335 | memcpy(to + sg->length - sg_remaining, from, |
336 | copy_bytes); | |
f97ec7db | 337 | |
26418649 SY |
338 | sg_remaining -= copy_bytes; |
339 | block_remaining -= copy_bytes; | |
f97ec7db | 340 | } |
e2e21bd8 | 341 | kunmap_atomic(to - sg->offset); |
f97ec7db IT |
342 | } |
343 | } | |
344 | ||
26418649 SY |
345 | static inline size_t spc_bitmap_free(unsigned long *bitmap) |
346 | { | |
347 | return DATA_BLOCK_SIZE * (DATA_BLOCK_BITS - | |
348 | bitmap_weight(bitmap, DATA_BLOCK_BITS)); | |
349 | } | |
350 | ||
7c9e7a6f | 351 | /* |
f97ec7db | 352 | * We can't queue a command until we have space available on the cmd ring *and* |
3d9b9555 | 353 | * space available on the data area. |
7c9e7a6f AG |
354 | * |
355 | * Called with ring lock held. | |
356 | */ | |
f56574a2 | 357 | static bool is_ring_space_avail(struct tcmu_dev *udev, size_t cmd_size, size_t data_needed) |
7c9e7a6f AG |
358 | { |
359 | struct tcmu_mailbox *mb = udev->mb_addr; | |
0241fd39 | 360 | size_t space, cmd_needed; |
7c9e7a6f AG |
361 | u32 cmd_head; |
362 | ||
363 | tcmu_flush_dcache_range(mb, sizeof(*mb)); | |
364 | ||
365 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
366 | ||
f56574a2 AG |
367 | /* |
368 | * If cmd end-of-ring space is too small then we need space for a NOP plus | |
369 | * original cmd - cmds are internally contiguous. | |
370 | */ | |
371 | if (head_to_end(cmd_head, udev->cmdr_size) >= cmd_size) | |
372 | cmd_needed = cmd_size; | |
373 | else | |
374 | cmd_needed = cmd_size + head_to_end(cmd_head, udev->cmdr_size); | |
375 | ||
7c9e7a6f AG |
376 | space = spc_free(cmd_head, udev->cmdr_last_cleaned, udev->cmdr_size); |
377 | if (space < cmd_needed) { | |
378 | pr_debug("no cmd space: %u %u %u\n", cmd_head, | |
379 | udev->cmdr_last_cleaned, udev->cmdr_size); | |
380 | return false; | |
381 | } | |
382 | ||
26418649 | 383 | space = spc_bitmap_free(udev->data_bitmap); |
7c9e7a6f | 384 | if (space < data_needed) { |
0241fd39 | 385 | pr_debug("no data space: only %zu available, but ask for %zu\n", |
26418649 | 386 | space, data_needed); |
7c9e7a6f AG |
387 | return false; |
388 | } | |
389 | ||
390 | return true; | |
391 | } | |
392 | ||
02eb924f AG |
393 | static sense_reason_t |
394 | tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd) | |
7c9e7a6f AG |
395 | { |
396 | struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; | |
397 | struct se_cmd *se_cmd = tcmu_cmd->se_cmd; | |
398 | size_t base_command_size, command_size; | |
7c9e7a6f | 399 | struct tcmu_mailbox *mb; |
7c9e7a6f | 400 | struct tcmu_cmd_entry *entry; |
7c9e7a6f | 401 | struct iovec *iov; |
f97ec7db | 402 | int iov_cnt; |
7c9e7a6f AG |
403 | uint32_t cmd_head; |
404 | uint64_t cdb_off; | |
f97ec7db | 405 | bool copy_to_data_area; |
26418649 SY |
406 | size_t data_length; |
407 | DECLARE_BITMAP(old_bitmap, DATA_BLOCK_BITS); | |
7c9e7a6f AG |
408 | |
409 | if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) | |
02eb924f | 410 | return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; |
7c9e7a6f AG |
411 | |
412 | /* | |
413 | * Must be a certain minimum size for response sense info, but | |
414 | * also may be larger if the iov array is large. | |
415 | * | |
26418649 SY |
416 | * We prepare way too many iovs for potential uses here, because it's |
417 | * expensive to tell how many regions are freed in the bitmap | |
7c9e7a6f | 418 | */ |
26418649 SY |
419 | base_command_size = max(offsetof(struct tcmu_cmd_entry, |
420 | req.iov[se_cmd->t_bidi_data_nents + | |
421 | se_cmd->t_data_nents]), | |
7c9e7a6f AG |
422 | sizeof(struct tcmu_cmd_entry)); |
423 | command_size = base_command_size | |
424 | + round_up(scsi_command_size(se_cmd->t_task_cdb), TCMU_OP_ALIGN_SIZE); | |
425 | ||
426 | WARN_ON(command_size & (TCMU_OP_ALIGN_SIZE-1)); | |
427 | ||
428 | spin_lock_irq(&udev->cmdr_lock); | |
429 | ||
430 | mb = udev->mb_addr; | |
431 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
26418649 SY |
432 | data_length = se_cmd->data_length; |
433 | if (se_cmd->se_cmd_flags & SCF_BIDI) { | |
434 | BUG_ON(!(se_cmd->t_bidi_data_sg && se_cmd->t_bidi_data_nents)); | |
435 | data_length += se_cmd->t_bidi_data_sg->length; | |
436 | } | |
554617b2 AG |
437 | if ((command_size > (udev->cmdr_size / 2)) || |
438 | data_length > udev->data_size) { | |
439 | pr_warn("TCMU: Request of size %zu/%zu is too big for %u/%zu " | |
3d9b9555 | 440 | "cmd ring/data area\n", command_size, data_length, |
7c9e7a6f | 441 | udev->cmdr_size, udev->data_size); |
554617b2 AG |
442 | spin_unlock_irq(&udev->cmdr_lock); |
443 | return TCM_INVALID_CDB_FIELD; | |
444 | } | |
7c9e7a6f | 445 | |
26418649 | 446 | while (!is_ring_space_avail(udev, command_size, data_length)) { |
7c9e7a6f AG |
447 | int ret; |
448 | DEFINE_WAIT(__wait); | |
449 | ||
450 | prepare_to_wait(&udev->wait_cmdr, &__wait, TASK_INTERRUPTIBLE); | |
451 | ||
452 | pr_debug("sleeping for ring space\n"); | |
453 | spin_unlock_irq(&udev->cmdr_lock); | |
454 | ret = schedule_timeout(msecs_to_jiffies(TCMU_TIME_OUT)); | |
455 | finish_wait(&udev->wait_cmdr, &__wait); | |
456 | if (!ret) { | |
457 | pr_warn("tcmu: command timed out\n"); | |
02eb924f | 458 | return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; |
7c9e7a6f AG |
459 | } |
460 | ||
461 | spin_lock_irq(&udev->cmdr_lock); | |
462 | ||
463 | /* We dropped cmdr_lock, cmd_head is stale */ | |
464 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
465 | } | |
466 | ||
f56574a2 AG |
467 | /* Insert a PAD if end-of-ring space is too small */ |
468 | if (head_to_end(cmd_head, udev->cmdr_size) < command_size) { | |
469 | size_t pad_size = head_to_end(cmd_head, udev->cmdr_size); | |
470 | ||
7c9e7a6f AG |
471 | entry = (void *) mb + CMDR_OFF + cmd_head; |
472 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
0ad46af8 AG |
473 | tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_PAD); |
474 | tcmu_hdr_set_len(&entry->hdr.len_op, pad_size); | |
475 | entry->hdr.cmd_id = 0; /* not used for PAD */ | |
476 | entry->hdr.kflags = 0; | |
477 | entry->hdr.uflags = 0; | |
7c9e7a6f AG |
478 | |
479 | UPDATE_HEAD(mb->cmd_head, pad_size, udev->cmdr_size); | |
480 | ||
481 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ | |
482 | WARN_ON(cmd_head != 0); | |
483 | } | |
484 | ||
485 | entry = (void *) mb + CMDR_OFF + cmd_head; | |
486 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
0ad46af8 AG |
487 | tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_CMD); |
488 | tcmu_hdr_set_len(&entry->hdr.len_op, command_size); | |
489 | entry->hdr.cmd_id = tcmu_cmd->cmd_id; | |
490 | entry->hdr.kflags = 0; | |
491 | entry->hdr.uflags = 0; | |
7c9e7a6f | 492 | |
26418649 SY |
493 | bitmap_copy(old_bitmap, udev->data_bitmap, DATA_BLOCK_BITS); |
494 | ||
3d9b9555 | 495 | /* Handle allocating space from the data area */ |
7c9e7a6f | 496 | iov = &entry->req.iov[0]; |
f97ec7db | 497 | iov_cnt = 0; |
e4648b01 IT |
498 | copy_to_data_area = (se_cmd->data_direction == DMA_TO_DEVICE |
499 | || se_cmd->se_cmd_flags & SCF_BIDI); | |
f97ec7db IT |
500 | alloc_and_scatter_data_area(udev, se_cmd->t_data_sg, |
501 | se_cmd->t_data_nents, &iov, &iov_cnt, copy_to_data_area); | |
7c9e7a6f | 502 | entry->req.iov_cnt = iov_cnt; |
0ad46af8 | 503 | entry->req.iov_dif_cnt = 0; |
7c9e7a6f | 504 | |
e4648b01 IT |
505 | /* Handle BIDI commands */ |
506 | iov_cnt = 0; | |
507 | alloc_and_scatter_data_area(udev, se_cmd->t_bidi_data_sg, | |
508 | se_cmd->t_bidi_data_nents, &iov, &iov_cnt, false); | |
509 | entry->req.iov_bidi_cnt = iov_cnt; | |
510 | ||
26418649 SY |
511 | /* cmd's data_bitmap is what changed in process */ |
512 | bitmap_xor(tcmu_cmd->data_bitmap, old_bitmap, udev->data_bitmap, | |
513 | DATA_BLOCK_BITS); | |
514 | ||
7c9e7a6f AG |
515 | /* All offsets relative to mb_addr, not start of entry! */ |
516 | cdb_off = CMDR_OFF + cmd_head + base_command_size; | |
517 | memcpy((void *) mb + cdb_off, se_cmd->t_task_cdb, scsi_command_size(se_cmd->t_task_cdb)); | |
518 | entry->req.cdb_off = cdb_off; | |
519 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
520 | ||
521 | UPDATE_HEAD(mb->cmd_head, command_size, udev->cmdr_size); | |
522 | tcmu_flush_dcache_range(mb, sizeof(*mb)); | |
523 | ||
524 | spin_unlock_irq(&udev->cmdr_lock); | |
525 | ||
526 | /* TODO: only if FLUSH and FUA? */ | |
527 | uio_event_notify(&udev->uio_info); | |
528 | ||
529 | mod_timer(&udev->timeout, | |
530 | round_jiffies_up(jiffies + msecs_to_jiffies(TCMU_TIME_OUT))); | |
531 | ||
02eb924f | 532 | return TCM_NO_SENSE; |
7c9e7a6f AG |
533 | } |
534 | ||
02eb924f AG |
535 | static sense_reason_t |
536 | tcmu_queue_cmd(struct se_cmd *se_cmd) | |
7c9e7a6f AG |
537 | { |
538 | struct se_device *se_dev = se_cmd->se_dev; | |
539 | struct tcmu_dev *udev = TCMU_DEV(se_dev); | |
540 | struct tcmu_cmd *tcmu_cmd; | |
ecaf597b | 541 | sense_reason_t ret; |
7c9e7a6f AG |
542 | |
543 | tcmu_cmd = tcmu_alloc_cmd(se_cmd); | |
544 | if (!tcmu_cmd) | |
02eb924f | 545 | return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; |
7c9e7a6f AG |
546 | |
547 | ret = tcmu_queue_cmd_ring(tcmu_cmd); | |
02eb924f | 548 | if (ret != TCM_NO_SENSE) { |
7c9e7a6f AG |
549 | pr_err("TCMU: Could not queue command\n"); |
550 | spin_lock_irq(&udev->commands_lock); | |
551 | idr_remove(&udev->commands, tcmu_cmd->cmd_id); | |
552 | spin_unlock_irq(&udev->commands_lock); | |
553 | ||
554 | kmem_cache_free(tcmu_cmd_cache, tcmu_cmd); | |
555 | } | |
556 | ||
557 | return ret; | |
558 | } | |
559 | ||
560 | static void tcmu_handle_completion(struct tcmu_cmd *cmd, struct tcmu_cmd_entry *entry) | |
561 | { | |
562 | struct se_cmd *se_cmd = cmd->se_cmd; | |
563 | struct tcmu_dev *udev = cmd->tcmu_dev; | |
564 | ||
565 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) { | |
b25c7863 SY |
566 | /* |
567 | * cmd has been completed already from timeout, just reclaim | |
3d9b9555 | 568 | * data area space and free cmd |
b25c7863 | 569 | */ |
26418649 | 570 | free_data_area(udev, cmd); |
b25c7863 SY |
571 | |
572 | kmem_cache_free(tcmu_cmd_cache, cmd); | |
7c9e7a6f AG |
573 | return; |
574 | } | |
575 | ||
0ad46af8 | 576 | if (entry->hdr.uflags & TCMU_UFLAG_UNKNOWN_OP) { |
26418649 | 577 | free_data_area(udev, cmd); |
0ad46af8 AG |
578 | pr_warn("TCMU: Userspace set UNKNOWN_OP flag on se_cmd %p\n", |
579 | cmd->se_cmd); | |
ed97d0cd AG |
580 | entry->rsp.scsi_status = SAM_STAT_CHECK_CONDITION; |
581 | } else if (entry->rsp.scsi_status == SAM_STAT_CHECK_CONDITION) { | |
7c9e7a6f AG |
582 | memcpy(se_cmd->sense_buffer, entry->rsp.sense_buffer, |
583 | se_cmd->scsi_sense_length); | |
26418649 | 584 | free_data_area(udev, cmd); |
e4648b01 | 585 | } else if (se_cmd->se_cmd_flags & SCF_BIDI) { |
26418649 | 586 | DECLARE_BITMAP(bitmap, DATA_BLOCK_BITS); |
e4648b01 | 587 | |
26418649 SY |
588 | /* Get Data-In buffer before clean up */ |
589 | bitmap_copy(bitmap, cmd->data_bitmap, DATA_BLOCK_BITS); | |
590 | gather_data_area(udev, bitmap, | |
e4648b01 | 591 | se_cmd->t_bidi_data_sg, se_cmd->t_bidi_data_nents); |
26418649 | 592 | free_data_area(udev, cmd); |
e4648b01 | 593 | } else if (se_cmd->data_direction == DMA_FROM_DEVICE) { |
26418649 SY |
594 | DECLARE_BITMAP(bitmap, DATA_BLOCK_BITS); |
595 | ||
596 | bitmap_copy(bitmap, cmd->data_bitmap, DATA_BLOCK_BITS); | |
597 | gather_data_area(udev, bitmap, | |
f97ec7db | 598 | se_cmd->t_data_sg, se_cmd->t_data_nents); |
26418649 | 599 | free_data_area(udev, cmd); |
7c9e7a6f | 600 | } else if (se_cmd->data_direction == DMA_TO_DEVICE) { |
26418649 | 601 | free_data_area(udev, cmd); |
2bc396a2 IT |
602 | } else if (se_cmd->data_direction != DMA_NONE) { |
603 | pr_warn("TCMU: data direction was %d!\n", | |
604 | se_cmd->data_direction); | |
7c9e7a6f AG |
605 | } |
606 | ||
607 | target_complete_cmd(cmd->se_cmd, entry->rsp.scsi_status); | |
608 | cmd->se_cmd = NULL; | |
609 | ||
610 | kmem_cache_free(tcmu_cmd_cache, cmd); | |
611 | } | |
612 | ||
613 | static unsigned int tcmu_handle_completions(struct tcmu_dev *udev) | |
614 | { | |
615 | struct tcmu_mailbox *mb; | |
7c9e7a6f AG |
616 | unsigned long flags; |
617 | int handled = 0; | |
618 | ||
619 | if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) { | |
620 | pr_err("ring broken, not handling completions\n"); | |
621 | return 0; | |
622 | } | |
623 | ||
624 | spin_lock_irqsave(&udev->cmdr_lock, flags); | |
625 | ||
626 | mb = udev->mb_addr; | |
627 | tcmu_flush_dcache_range(mb, sizeof(*mb)); | |
628 | ||
629 | while (udev->cmdr_last_cleaned != ACCESS_ONCE(mb->cmd_tail)) { | |
630 | ||
631 | struct tcmu_cmd_entry *entry = (void *) mb + CMDR_OFF + udev->cmdr_last_cleaned; | |
632 | struct tcmu_cmd *cmd; | |
633 | ||
634 | tcmu_flush_dcache_range(entry, sizeof(*entry)); | |
635 | ||
0ad46af8 AG |
636 | if (tcmu_hdr_get_op(entry->hdr.len_op) == TCMU_OP_PAD) { |
637 | UPDATE_HEAD(udev->cmdr_last_cleaned, | |
638 | tcmu_hdr_get_len(entry->hdr.len_op), | |
639 | udev->cmdr_size); | |
7c9e7a6f AG |
640 | continue; |
641 | } | |
0ad46af8 | 642 | WARN_ON(tcmu_hdr_get_op(entry->hdr.len_op) != TCMU_OP_CMD); |
7c9e7a6f AG |
643 | |
644 | spin_lock(&udev->commands_lock); | |
0ad46af8 | 645 | cmd = idr_find(&udev->commands, entry->hdr.cmd_id); |
7c9e7a6f AG |
646 | if (cmd) |
647 | idr_remove(&udev->commands, cmd->cmd_id); | |
648 | spin_unlock(&udev->commands_lock); | |
649 | ||
650 | if (!cmd) { | |
651 | pr_err("cmd_id not found, ring is broken\n"); | |
652 | set_bit(TCMU_DEV_BIT_BROKEN, &udev->flags); | |
653 | break; | |
654 | } | |
655 | ||
656 | tcmu_handle_completion(cmd, entry); | |
657 | ||
0ad46af8 AG |
658 | UPDATE_HEAD(udev->cmdr_last_cleaned, |
659 | tcmu_hdr_get_len(entry->hdr.len_op), | |
660 | udev->cmdr_size); | |
7c9e7a6f AG |
661 | |
662 | handled++; | |
663 | } | |
664 | ||
665 | if (mb->cmd_tail == mb->cmd_head) | |
666 | del_timer(&udev->timeout); /* no more pending cmds */ | |
667 | ||
668 | spin_unlock_irqrestore(&udev->cmdr_lock, flags); | |
669 | ||
670 | wake_up(&udev->wait_cmdr); | |
671 | ||
672 | return handled; | |
673 | } | |
674 | ||
675 | static int tcmu_check_expired_cmd(int id, void *p, void *data) | |
676 | { | |
677 | struct tcmu_cmd *cmd = p; | |
678 | ||
679 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) | |
680 | return 0; | |
681 | ||
611e2267 | 682 | if (!time_after(jiffies, cmd->deadline)) |
7c9e7a6f AG |
683 | return 0; |
684 | ||
685 | set_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags); | |
686 | target_complete_cmd(cmd->se_cmd, SAM_STAT_CHECK_CONDITION); | |
687 | cmd->se_cmd = NULL; | |
688 | ||
7c9e7a6f AG |
689 | return 0; |
690 | } | |
691 | ||
692 | static void tcmu_device_timedout(unsigned long data) | |
693 | { | |
694 | struct tcmu_dev *udev = (struct tcmu_dev *)data; | |
695 | unsigned long flags; | |
696 | int handled; | |
697 | ||
698 | handled = tcmu_handle_completions(udev); | |
699 | ||
700 | pr_warn("%d completions handled from timeout\n", handled); | |
701 | ||
702 | spin_lock_irqsave(&udev->commands_lock, flags); | |
703 | idr_for_each(&udev->commands, tcmu_check_expired_cmd, NULL); | |
704 | spin_unlock_irqrestore(&udev->commands_lock, flags); | |
705 | ||
706 | /* | |
707 | * We don't need to wakeup threads on wait_cmdr since they have their | |
708 | * own timeout. | |
709 | */ | |
710 | } | |
711 | ||
712 | static int tcmu_attach_hba(struct se_hba *hba, u32 host_id) | |
713 | { | |
714 | struct tcmu_hba *tcmu_hba; | |
715 | ||
716 | tcmu_hba = kzalloc(sizeof(struct tcmu_hba), GFP_KERNEL); | |
717 | if (!tcmu_hba) | |
718 | return -ENOMEM; | |
719 | ||
720 | tcmu_hba->host_id = host_id; | |
721 | hba->hba_ptr = tcmu_hba; | |
722 | ||
723 | return 0; | |
724 | } | |
725 | ||
726 | static void tcmu_detach_hba(struct se_hba *hba) | |
727 | { | |
728 | kfree(hba->hba_ptr); | |
729 | hba->hba_ptr = NULL; | |
730 | } | |
731 | ||
732 | static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name) | |
733 | { | |
734 | struct tcmu_dev *udev; | |
735 | ||
736 | udev = kzalloc(sizeof(struct tcmu_dev), GFP_KERNEL); | |
737 | if (!udev) | |
738 | return NULL; | |
739 | ||
740 | udev->name = kstrdup(name, GFP_KERNEL); | |
741 | if (!udev->name) { | |
742 | kfree(udev); | |
743 | return NULL; | |
744 | } | |
745 | ||
746 | udev->hba = hba; | |
747 | ||
748 | init_waitqueue_head(&udev->wait_cmdr); | |
749 | spin_lock_init(&udev->cmdr_lock); | |
750 | ||
751 | idr_init(&udev->commands); | |
752 | spin_lock_init(&udev->commands_lock); | |
753 | ||
754 | setup_timer(&udev->timeout, tcmu_device_timedout, | |
755 | (unsigned long)udev); | |
756 | ||
7c9e7a6f AG |
757 | return &udev->se_dev; |
758 | } | |
759 | ||
760 | static int tcmu_irqcontrol(struct uio_info *info, s32 irq_on) | |
761 | { | |
762 | struct tcmu_dev *tcmu_dev = container_of(info, struct tcmu_dev, uio_info); | |
763 | ||
764 | tcmu_handle_completions(tcmu_dev); | |
765 | ||
766 | return 0; | |
767 | } | |
768 | ||
769 | /* | |
770 | * mmap code from uio.c. Copied here because we want to hook mmap() | |
771 | * and this stuff must come along. | |
772 | */ | |
773 | static int tcmu_find_mem_index(struct vm_area_struct *vma) | |
774 | { | |
775 | struct tcmu_dev *udev = vma->vm_private_data; | |
776 | struct uio_info *info = &udev->uio_info; | |
777 | ||
778 | if (vma->vm_pgoff < MAX_UIO_MAPS) { | |
779 | if (info->mem[vma->vm_pgoff].size == 0) | |
780 | return -1; | |
781 | return (int)vma->vm_pgoff; | |
782 | } | |
783 | return -1; | |
784 | } | |
785 | ||
786 | static int tcmu_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf) | |
787 | { | |
788 | struct tcmu_dev *udev = vma->vm_private_data; | |
789 | struct uio_info *info = &udev->uio_info; | |
790 | struct page *page; | |
791 | unsigned long offset; | |
792 | void *addr; | |
793 | ||
794 | int mi = tcmu_find_mem_index(vma); | |
795 | if (mi < 0) | |
796 | return VM_FAULT_SIGBUS; | |
797 | ||
798 | /* | |
799 | * We need to subtract mi because userspace uses offset = N*PAGE_SIZE | |
800 | * to use mem[N]. | |
801 | */ | |
802 | offset = (vmf->pgoff - mi) << PAGE_SHIFT; | |
803 | ||
804 | addr = (void *)(unsigned long)info->mem[mi].addr + offset; | |
805 | if (info->mem[mi].memtype == UIO_MEM_LOGICAL) | |
806 | page = virt_to_page(addr); | |
807 | else | |
808 | page = vmalloc_to_page(addr); | |
809 | get_page(page); | |
810 | vmf->page = page; | |
811 | return 0; | |
812 | } | |
813 | ||
814 | static const struct vm_operations_struct tcmu_vm_ops = { | |
815 | .fault = tcmu_vma_fault, | |
816 | }; | |
817 | ||
818 | static int tcmu_mmap(struct uio_info *info, struct vm_area_struct *vma) | |
819 | { | |
820 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); | |
821 | ||
822 | vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; | |
823 | vma->vm_ops = &tcmu_vm_ops; | |
824 | ||
825 | vma->vm_private_data = udev; | |
826 | ||
827 | /* Ensure the mmap is exactly the right size */ | |
828 | if (vma_pages(vma) != (TCMU_RING_SIZE >> PAGE_SHIFT)) | |
829 | return -EINVAL; | |
830 | ||
831 | return 0; | |
832 | } | |
833 | ||
834 | static int tcmu_open(struct uio_info *info, struct inode *inode) | |
835 | { | |
836 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); | |
837 | ||
838 | /* O_EXCL not supported for char devs, so fake it? */ | |
839 | if (test_and_set_bit(TCMU_DEV_BIT_OPEN, &udev->flags)) | |
840 | return -EBUSY; | |
841 | ||
842 | pr_debug("open\n"); | |
843 | ||
844 | return 0; | |
845 | } | |
846 | ||
847 | static int tcmu_release(struct uio_info *info, struct inode *inode) | |
848 | { | |
849 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); | |
850 | ||
851 | clear_bit(TCMU_DEV_BIT_OPEN, &udev->flags); | |
852 | ||
853 | pr_debug("close\n"); | |
854 | ||
855 | return 0; | |
856 | } | |
857 | ||
858 | static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name, int minor) | |
859 | { | |
860 | struct sk_buff *skb; | |
861 | void *msg_header; | |
6e14eab9 | 862 | int ret = -ENOMEM; |
7c9e7a6f AG |
863 | |
864 | skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); | |
865 | if (!skb) | |
6e14eab9 | 866 | return ret; |
7c9e7a6f AG |
867 | |
868 | msg_header = genlmsg_put(skb, 0, 0, &tcmu_genl_family, 0, cmd); | |
6e14eab9 NB |
869 | if (!msg_header) |
870 | goto free_skb; | |
7c9e7a6f AG |
871 | |
872 | ret = nla_put_string(skb, TCMU_ATTR_DEVICE, name); | |
6e14eab9 NB |
873 | if (ret < 0) |
874 | goto free_skb; | |
7c9e7a6f AG |
875 | |
876 | ret = nla_put_u32(skb, TCMU_ATTR_MINOR, minor); | |
6e14eab9 NB |
877 | if (ret < 0) |
878 | goto free_skb; | |
7c9e7a6f | 879 | |
053c095a | 880 | genlmsg_end(skb, msg_header); |
7c9e7a6f | 881 | |
20c08b36 | 882 | ret = genlmsg_multicast_allns(&tcmu_genl_family, skb, 0, |
7c9e7a6f AG |
883 | TCMU_MCGRP_CONFIG, GFP_KERNEL); |
884 | ||
885 | /* We don't care if no one is listening */ | |
886 | if (ret == -ESRCH) | |
887 | ret = 0; | |
888 | ||
889 | return ret; | |
6e14eab9 NB |
890 | free_skb: |
891 | nlmsg_free(skb); | |
892 | return ret; | |
7c9e7a6f AG |
893 | } |
894 | ||
895 | static int tcmu_configure_device(struct se_device *dev) | |
896 | { | |
897 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
898 | struct tcmu_hba *hba = udev->hba->hba_ptr; | |
899 | struct uio_info *info; | |
900 | struct tcmu_mailbox *mb; | |
901 | size_t size; | |
902 | size_t used; | |
903 | int ret = 0; | |
904 | char *str; | |
905 | ||
906 | info = &udev->uio_info; | |
907 | ||
908 | size = snprintf(NULL, 0, "tcm-user/%u/%s/%s", hba->host_id, udev->name, | |
909 | udev->dev_config); | |
910 | size += 1; /* for \0 */ | |
911 | str = kmalloc(size, GFP_KERNEL); | |
912 | if (!str) | |
913 | return -ENOMEM; | |
914 | ||
915 | used = snprintf(str, size, "tcm-user/%u/%s", hba->host_id, udev->name); | |
916 | ||
917 | if (udev->dev_config[0]) | |
918 | snprintf(str + used, size - used, "/%s", udev->dev_config); | |
919 | ||
920 | info->name = str; | |
921 | ||
922 | udev->mb_addr = vzalloc(TCMU_RING_SIZE); | |
923 | if (!udev->mb_addr) { | |
924 | ret = -ENOMEM; | |
925 | goto err_vzalloc; | |
926 | } | |
927 | ||
928 | /* mailbox fits in first part of CMDR space */ | |
929 | udev->cmdr_size = CMDR_SIZE - CMDR_OFF; | |
930 | udev->data_off = CMDR_SIZE; | |
931 | udev->data_size = TCMU_RING_SIZE - CMDR_SIZE; | |
932 | ||
933 | mb = udev->mb_addr; | |
0ad46af8 | 934 | mb->version = TCMU_MAILBOX_VERSION; |
32c76de3 | 935 | mb->flags = TCMU_MAILBOX_FLAG_CAP_OOOC; |
7c9e7a6f AG |
936 | mb->cmdr_off = CMDR_OFF; |
937 | mb->cmdr_size = udev->cmdr_size; | |
938 | ||
939 | WARN_ON(!PAGE_ALIGNED(udev->data_off)); | |
940 | WARN_ON(udev->data_size % PAGE_SIZE); | |
26418649 | 941 | WARN_ON(udev->data_size % DATA_BLOCK_SIZE); |
7c9e7a6f | 942 | |
ac64a2ce | 943 | info->version = __stringify(TCMU_MAILBOX_VERSION); |
7c9e7a6f AG |
944 | |
945 | info->mem[0].name = "tcm-user command & data buffer"; | |
0633e123 | 946 | info->mem[0].addr = (phys_addr_t)(uintptr_t)udev->mb_addr; |
7c9e7a6f AG |
947 | info->mem[0].size = TCMU_RING_SIZE; |
948 | info->mem[0].memtype = UIO_MEM_VIRTUAL; | |
949 | ||
950 | info->irqcontrol = tcmu_irqcontrol; | |
951 | info->irq = UIO_IRQ_CUSTOM; | |
952 | ||
953 | info->mmap = tcmu_mmap; | |
954 | info->open = tcmu_open; | |
955 | info->release = tcmu_release; | |
956 | ||
957 | ret = uio_register_device(tcmu_root_device, info); | |
958 | if (ret) | |
959 | goto err_register; | |
960 | ||
81ee28de SY |
961 | /* User can set hw_block_size before enable the device */ |
962 | if (dev->dev_attrib.hw_block_size == 0) | |
963 | dev->dev_attrib.hw_block_size = 512; | |
7c9e7a6f | 964 | /* Other attributes can be configured in userspace */ |
7c9e7a6f AG |
965 | dev->dev_attrib.hw_max_sectors = 128; |
966 | dev->dev_attrib.hw_queue_depth = 128; | |
967 | ||
968 | ret = tcmu_netlink_event(TCMU_CMD_ADDED_DEVICE, udev->uio_info.name, | |
969 | udev->uio_info.uio_dev->minor); | |
970 | if (ret) | |
971 | goto err_netlink; | |
972 | ||
973 | return 0; | |
974 | ||
975 | err_netlink: | |
976 | uio_unregister_device(&udev->uio_info); | |
977 | err_register: | |
978 | vfree(udev->mb_addr); | |
979 | err_vzalloc: | |
980 | kfree(info->name); | |
981 | ||
982 | return ret; | |
983 | } | |
984 | ||
b25c7863 | 985 | static int tcmu_check_and_free_pending_cmd(struct tcmu_cmd *cmd) |
7c9e7a6f | 986 | { |
b25c7863 SY |
987 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) { |
988 | kmem_cache_free(tcmu_cmd_cache, cmd); | |
7c9e7a6f | 989 | return 0; |
b25c7863 | 990 | } |
7c9e7a6f AG |
991 | return -EINVAL; |
992 | } | |
993 | ||
4cc987ea NB |
994 | static void tcmu_dev_call_rcu(struct rcu_head *p) |
995 | { | |
996 | struct se_device *dev = container_of(p, struct se_device, rcu_head); | |
997 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
998 | ||
999 | kfree(udev); | |
1000 | } | |
1001 | ||
7c9e7a6f AG |
1002 | static void tcmu_free_device(struct se_device *dev) |
1003 | { | |
1004 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
b25c7863 SY |
1005 | struct tcmu_cmd *cmd; |
1006 | bool all_expired = true; | |
7c9e7a6f AG |
1007 | int i; |
1008 | ||
1009 | del_timer_sync(&udev->timeout); | |
1010 | ||
1011 | vfree(udev->mb_addr); | |
1012 | ||
1013 | /* Upper layer should drain all requests before calling this */ | |
1014 | spin_lock_irq(&udev->commands_lock); | |
b25c7863 SY |
1015 | idr_for_each_entry(&udev->commands, cmd, i) { |
1016 | if (tcmu_check_and_free_pending_cmd(cmd) != 0) | |
1017 | all_expired = false; | |
1018 | } | |
7c9e7a6f AG |
1019 | idr_destroy(&udev->commands); |
1020 | spin_unlock_irq(&udev->commands_lock); | |
b25c7863 | 1021 | WARN_ON(!all_expired); |
7c9e7a6f AG |
1022 | |
1023 | /* Device was configured */ | |
1024 | if (udev->uio_info.uio_dev) { | |
1025 | tcmu_netlink_event(TCMU_CMD_REMOVED_DEVICE, udev->uio_info.name, | |
1026 | udev->uio_info.uio_dev->minor); | |
1027 | ||
1028 | uio_unregister_device(&udev->uio_info); | |
1029 | kfree(udev->uio_info.name); | |
1030 | kfree(udev->name); | |
1031 | } | |
4cc987ea | 1032 | call_rcu(&dev->rcu_head, tcmu_dev_call_rcu); |
7c9e7a6f AG |
1033 | } |
1034 | ||
1035 | enum { | |
9c1cd1b6 | 1036 | Opt_dev_config, Opt_dev_size, Opt_hw_block_size, Opt_err, |
7c9e7a6f AG |
1037 | }; |
1038 | ||
1039 | static match_table_t tokens = { | |
1040 | {Opt_dev_config, "dev_config=%s"}, | |
1041 | {Opt_dev_size, "dev_size=%u"}, | |
9c1cd1b6 | 1042 | {Opt_hw_block_size, "hw_block_size=%u"}, |
7c9e7a6f AG |
1043 | {Opt_err, NULL} |
1044 | }; | |
1045 | ||
1046 | static ssize_t tcmu_set_configfs_dev_params(struct se_device *dev, | |
1047 | const char *page, ssize_t count) | |
1048 | { | |
1049 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
1050 | char *orig, *ptr, *opts, *arg_p; | |
1051 | substring_t args[MAX_OPT_ARGS]; | |
1052 | int ret = 0, token; | |
9c1cd1b6 | 1053 | unsigned long tmp_ul; |
7c9e7a6f AG |
1054 | |
1055 | opts = kstrdup(page, GFP_KERNEL); | |
1056 | if (!opts) | |
1057 | return -ENOMEM; | |
1058 | ||
1059 | orig = opts; | |
1060 | ||
1061 | while ((ptr = strsep(&opts, ",\n")) != NULL) { | |
1062 | if (!*ptr) | |
1063 | continue; | |
1064 | ||
1065 | token = match_token(ptr, tokens, args); | |
1066 | switch (token) { | |
1067 | case Opt_dev_config: | |
1068 | if (match_strlcpy(udev->dev_config, &args[0], | |
1069 | TCMU_CONFIG_LEN) == 0) { | |
1070 | ret = -EINVAL; | |
1071 | break; | |
1072 | } | |
1073 | pr_debug("TCMU: Referencing Path: %s\n", udev->dev_config); | |
1074 | break; | |
1075 | case Opt_dev_size: | |
1076 | arg_p = match_strdup(&args[0]); | |
1077 | if (!arg_p) { | |
1078 | ret = -ENOMEM; | |
1079 | break; | |
1080 | } | |
1081 | ret = kstrtoul(arg_p, 0, (unsigned long *) &udev->dev_size); | |
1082 | kfree(arg_p); | |
1083 | if (ret < 0) | |
1084 | pr_err("kstrtoul() failed for dev_size=\n"); | |
1085 | break; | |
9c1cd1b6 AG |
1086 | case Opt_hw_block_size: |
1087 | arg_p = match_strdup(&args[0]); | |
1088 | if (!arg_p) { | |
1089 | ret = -ENOMEM; | |
1090 | break; | |
1091 | } | |
1092 | ret = kstrtoul(arg_p, 0, &tmp_ul); | |
1093 | kfree(arg_p); | |
1094 | if (ret < 0) { | |
1095 | pr_err("kstrtoul() failed for hw_block_size=\n"); | |
1096 | break; | |
1097 | } | |
1098 | if (!tmp_ul) { | |
1099 | pr_err("hw_block_size must be nonzero\n"); | |
1100 | break; | |
1101 | } | |
1102 | dev->dev_attrib.hw_block_size = tmp_ul; | |
1103 | break; | |
7c9e7a6f AG |
1104 | default: |
1105 | break; | |
1106 | } | |
1107 | } | |
1108 | ||
1109 | kfree(orig); | |
1110 | return (!ret) ? count : ret; | |
1111 | } | |
1112 | ||
1113 | static ssize_t tcmu_show_configfs_dev_params(struct se_device *dev, char *b) | |
1114 | { | |
1115 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
1116 | ssize_t bl = 0; | |
1117 | ||
1118 | bl = sprintf(b + bl, "Config: %s ", | |
1119 | udev->dev_config[0] ? udev->dev_config : "NULL"); | |
8ee83a74 | 1120 | bl += sprintf(b + bl, "Size: %zu\n", udev->dev_size); |
7c9e7a6f AG |
1121 | |
1122 | return bl; | |
1123 | } | |
1124 | ||
1125 | static sector_t tcmu_get_blocks(struct se_device *dev) | |
1126 | { | |
1127 | struct tcmu_dev *udev = TCMU_DEV(dev); | |
1128 | ||
1129 | return div_u64(udev->dev_size - dev->dev_attrib.block_size, | |
1130 | dev->dev_attrib.block_size); | |
1131 | } | |
1132 | ||
7c9e7a6f | 1133 | static sense_reason_t |
9c1cd1b6 | 1134 | tcmu_parse_cdb(struct se_cmd *cmd) |
7c9e7a6f | 1135 | { |
02eb924f | 1136 | return passthrough_parse_cdb(cmd, tcmu_queue_cmd); |
7c9e7a6f AG |
1137 | } |
1138 | ||
0a06d430 | 1139 | static const struct target_backend_ops tcmu_ops = { |
7c9e7a6f | 1140 | .name = "user", |
7c9e7a6f | 1141 | .owner = THIS_MODULE, |
a3541703 | 1142 | .transport_flags = TRANSPORT_FLAG_PASSTHROUGH, |
7c9e7a6f AG |
1143 | .attach_hba = tcmu_attach_hba, |
1144 | .detach_hba = tcmu_detach_hba, | |
1145 | .alloc_device = tcmu_alloc_device, | |
1146 | .configure_device = tcmu_configure_device, | |
1147 | .free_device = tcmu_free_device, | |
1148 | .parse_cdb = tcmu_parse_cdb, | |
1149 | .set_configfs_dev_params = tcmu_set_configfs_dev_params, | |
1150 | .show_configfs_dev_params = tcmu_show_configfs_dev_params, | |
1151 | .get_device_type = sbc_get_device_type, | |
1152 | .get_blocks = tcmu_get_blocks, | |
5873c4d1 | 1153 | .tb_dev_attrib_attrs = passthrough_attrib_attrs, |
7c9e7a6f AG |
1154 | }; |
1155 | ||
1156 | static int __init tcmu_module_init(void) | |
1157 | { | |
1158 | int ret; | |
1159 | ||
1160 | BUILD_BUG_ON((sizeof(struct tcmu_cmd_entry) % TCMU_OP_ALIGN_SIZE) != 0); | |
1161 | ||
1162 | tcmu_cmd_cache = kmem_cache_create("tcmu_cmd_cache", | |
1163 | sizeof(struct tcmu_cmd), | |
1164 | __alignof__(struct tcmu_cmd), | |
1165 | 0, NULL); | |
1166 | if (!tcmu_cmd_cache) | |
1167 | return -ENOMEM; | |
1168 | ||
1169 | tcmu_root_device = root_device_register("tcm_user"); | |
1170 | if (IS_ERR(tcmu_root_device)) { | |
1171 | ret = PTR_ERR(tcmu_root_device); | |
1172 | goto out_free_cache; | |
1173 | } | |
1174 | ||
1175 | ret = genl_register_family(&tcmu_genl_family); | |
1176 | if (ret < 0) { | |
1177 | goto out_unreg_device; | |
1178 | } | |
1179 | ||
0a06d430 | 1180 | ret = transport_backend_register(&tcmu_ops); |
7c9e7a6f AG |
1181 | if (ret) |
1182 | goto out_unreg_genl; | |
1183 | ||
1184 | return 0; | |
1185 | ||
1186 | out_unreg_genl: | |
1187 | genl_unregister_family(&tcmu_genl_family); | |
1188 | out_unreg_device: | |
1189 | root_device_unregister(tcmu_root_device); | |
1190 | out_free_cache: | |
1191 | kmem_cache_destroy(tcmu_cmd_cache); | |
1192 | ||
1193 | return ret; | |
1194 | } | |
1195 | ||
1196 | static void __exit tcmu_module_exit(void) | |
1197 | { | |
0a06d430 | 1198 | target_backend_unregister(&tcmu_ops); |
7c9e7a6f AG |
1199 | genl_unregister_family(&tcmu_genl_family); |
1200 | root_device_unregister(tcmu_root_device); | |
1201 | kmem_cache_destroy(tcmu_cmd_cache); | |
1202 | } | |
1203 | ||
1204 | MODULE_DESCRIPTION("TCM USER subsystem plugin"); | |
1205 | MODULE_AUTHOR("Shaohua Li <shli@kernel.org>"); | |
1206 | MODULE_AUTHOR("Andy Grover <agrover@redhat.com>"); | |
1207 | MODULE_LICENSE("GPL"); | |
1208 | ||
1209 | module_init(tcmu_module_init); | |
1210 | module_exit(tcmu_module_exit); |