Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2013 Shaohua Li <shli@kernel.org> |
| 3 | * Copyright (C) 2014 Red Hat, Inc. |
Ilias Tsitsimpis | f97ec7d | 2015-04-23 21:47:00 +0300 | [diff] [blame] | 4 | * Copyright (C) 2015 Arrikto, Inc. |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 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> |
| 23 | #include <linux/timer.h> |
| 24 | #include <linux/parser.h> |
| 25 | #include <scsi/scsi.h> |
| 26 | #include <scsi/scsi_host.h> |
| 27 | #include <linux/uio_driver.h> |
| 28 | #include <net/genetlink.h> |
| 29 | #include <target/target_core_base.h> |
| 30 | #include <target/target_core_fabric.h> |
| 31 | #include <target/target_core_backend.h> |
Nicholas Bellinger | e9f720d | 2014-11-28 05:11:24 +0000 | [diff] [blame] | 32 | |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 33 | #include <linux/target_core_user.h> |
| 34 | |
| 35 | /* |
| 36 | * Define a shared-memory interface for LIO to pass SCSI commands and |
| 37 | * data to userspace for processing. This is to allow backends that |
| 38 | * are too complex for in-kernel support to be possible. |
| 39 | * |
| 40 | * It uses the UIO framework to do a lot of the device-creation and |
| 41 | * introspection work for us. |
| 42 | * |
| 43 | * See the .h file for how the ring is laid out. Note that while the |
| 44 | * command ring is defined, the particulars of the data area are |
| 45 | * not. Offset values in the command entry point to other locations |
| 46 | * internal to the mmap()ed area. There is separate space outside the |
| 47 | * command ring for data buffers. This leaves maximum flexibility for |
| 48 | * moving buffer allocations, or even page flipping or other |
| 49 | * allocation techniques, without altering the command ring layout. |
| 50 | * |
| 51 | * SECURITY: |
| 52 | * The user process must be assumed to be malicious. There's no way to |
| 53 | * prevent it breaking the command ring protocol if it wants, but in |
| 54 | * order to prevent other issues we must only ever read *data* from |
| 55 | * the shared memory area, not offsets or sizes. This applies to |
| 56 | * command ring entries as well as the mailbox. Extra code needed for |
| 57 | * this may have a 'UAM' comment. |
| 58 | */ |
| 59 | |
| 60 | |
| 61 | #define TCMU_TIME_OUT (30 * MSEC_PER_SEC) |
| 62 | |
| 63 | #define CMDR_SIZE (16 * 4096) |
| 64 | #define DATA_SIZE (257 * 4096) |
| 65 | |
| 66 | #define TCMU_RING_SIZE (CMDR_SIZE + DATA_SIZE) |
| 67 | |
| 68 | static struct device *tcmu_root_device; |
| 69 | |
| 70 | struct tcmu_hba { |
| 71 | u32 host_id; |
| 72 | }; |
| 73 | |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 74 | #define TCMU_CONFIG_LEN 256 |
| 75 | |
| 76 | struct tcmu_dev { |
| 77 | struct se_device se_dev; |
| 78 | |
| 79 | char *name; |
| 80 | struct se_hba *hba; |
| 81 | |
| 82 | #define TCMU_DEV_BIT_OPEN 0 |
| 83 | #define TCMU_DEV_BIT_BROKEN 1 |
| 84 | unsigned long flags; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 85 | |
| 86 | struct uio_info uio_info; |
| 87 | |
| 88 | struct tcmu_mailbox *mb_addr; |
| 89 | size_t dev_size; |
| 90 | u32 cmdr_size; |
| 91 | u32 cmdr_last_cleaned; |
| 92 | /* Offset of data ring from start of mb */ |
| 93 | size_t data_off; |
| 94 | size_t data_size; |
| 95 | /* Ring head + tail values. */ |
| 96 | /* Must add data_off and mb_addr to get the address */ |
| 97 | size_t data_head; |
| 98 | size_t data_tail; |
| 99 | |
| 100 | wait_queue_head_t wait_cmdr; |
| 101 | /* TODO should this be a mutex? */ |
| 102 | spinlock_t cmdr_lock; |
| 103 | |
| 104 | struct idr commands; |
| 105 | spinlock_t commands_lock; |
| 106 | |
| 107 | struct timer_list timeout; |
| 108 | |
| 109 | char dev_config[TCMU_CONFIG_LEN]; |
| 110 | }; |
| 111 | |
| 112 | #define TCMU_DEV(_se_dev) container_of(_se_dev, struct tcmu_dev, se_dev) |
| 113 | |
| 114 | #define CMDR_OFF sizeof(struct tcmu_mailbox) |
| 115 | |
| 116 | struct tcmu_cmd { |
| 117 | struct se_cmd *se_cmd; |
| 118 | struct tcmu_dev *tcmu_dev; |
| 119 | |
| 120 | uint16_t cmd_id; |
| 121 | |
| 122 | /* Can't use se_cmd->data_length when cleaning up expired cmds, because if |
| 123 | cmd has been completed then accessing se_cmd is off limits */ |
| 124 | size_t data_length; |
| 125 | |
| 126 | unsigned long deadline; |
| 127 | |
| 128 | #define TCMU_CMD_BIT_EXPIRED 0 |
| 129 | unsigned long flags; |
| 130 | }; |
| 131 | |
| 132 | static struct kmem_cache *tcmu_cmd_cache; |
| 133 | |
| 134 | /* multicast group */ |
| 135 | enum tcmu_multicast_groups { |
| 136 | TCMU_MCGRP_CONFIG, |
| 137 | }; |
| 138 | |
| 139 | static const struct genl_multicast_group tcmu_mcgrps[] = { |
| 140 | [TCMU_MCGRP_CONFIG] = { .name = "config", }, |
| 141 | }; |
| 142 | |
| 143 | /* Our generic netlink family */ |
| 144 | static struct genl_family tcmu_genl_family = { |
| 145 | .id = GENL_ID_GENERATE, |
| 146 | .hdrsize = 0, |
| 147 | .name = "TCM-USER", |
| 148 | .version = 1, |
| 149 | .maxattr = TCMU_ATTR_MAX, |
| 150 | .mcgrps = tcmu_mcgrps, |
| 151 | .n_mcgrps = ARRAY_SIZE(tcmu_mcgrps), |
| 152 | }; |
| 153 | |
| 154 | static struct tcmu_cmd *tcmu_alloc_cmd(struct se_cmd *se_cmd) |
| 155 | { |
| 156 | struct se_device *se_dev = se_cmd->se_dev; |
| 157 | struct tcmu_dev *udev = TCMU_DEV(se_dev); |
| 158 | struct tcmu_cmd *tcmu_cmd; |
| 159 | int cmd_id; |
| 160 | |
| 161 | tcmu_cmd = kmem_cache_zalloc(tcmu_cmd_cache, GFP_KERNEL); |
| 162 | if (!tcmu_cmd) |
| 163 | return NULL; |
| 164 | |
| 165 | tcmu_cmd->se_cmd = se_cmd; |
| 166 | tcmu_cmd->tcmu_dev = udev; |
| 167 | tcmu_cmd->data_length = se_cmd->data_length; |
| 168 | |
Ilias Tsitsimpis | e4648b0 | 2015-04-23 21:30:09 +0300 | [diff] [blame] | 169 | if (se_cmd->se_cmd_flags & SCF_BIDI) { |
| 170 | BUG_ON(!(se_cmd->t_bidi_data_sg && se_cmd->t_bidi_data_nents)); |
| 171 | tcmu_cmd->data_length += se_cmd->t_bidi_data_sg->length; |
| 172 | } |
| 173 | |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 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 | { |
| 194 | unsigned long offset = (unsigned long) vaddr & ~PAGE_MASK; |
| 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 | |
| 230 | #define UPDATE_HEAD(head, used, size) smp_store_release(&head, ((head % size) + used) % size) |
| 231 | |
Ilias Tsitsimpis | f97ec7d | 2015-04-23 21:47:00 +0300 | [diff] [blame] | 232 | static void alloc_and_scatter_data_area(struct tcmu_dev *udev, |
| 233 | struct scatterlist *data_sg, unsigned int data_nents, |
| 234 | struct iovec **iov, int *iov_cnt, bool copy_data) |
| 235 | { |
| 236 | int i; |
| 237 | void *from, *to; |
| 238 | size_t copy_bytes; |
| 239 | struct scatterlist *sg; |
| 240 | |
| 241 | for_each_sg(data_sg, sg, data_nents, i) { |
| 242 | copy_bytes = min_t(size_t, sg->length, |
| 243 | head_to_end(udev->data_head, udev->data_size)); |
| 244 | from = kmap_atomic(sg_page(sg)) + sg->offset; |
| 245 | to = (void *) udev->mb_addr + udev->data_off + udev->data_head; |
| 246 | |
| 247 | if (copy_data) { |
| 248 | memcpy(to, from, copy_bytes); |
| 249 | tcmu_flush_dcache_range(to, copy_bytes); |
| 250 | } |
| 251 | |
| 252 | /* Even iov_base is relative to mb_addr */ |
| 253 | (*iov)->iov_len = copy_bytes; |
| 254 | (*iov)->iov_base = (void __user *) udev->data_off + |
| 255 | udev->data_head; |
| 256 | (*iov_cnt)++; |
| 257 | (*iov)++; |
| 258 | |
| 259 | UPDATE_HEAD(udev->data_head, copy_bytes, udev->data_size); |
| 260 | |
| 261 | /* Uh oh, we wrapped the buffer. Must split sg across 2 iovs. */ |
| 262 | if (sg->length != copy_bytes) { |
| 263 | from += copy_bytes; |
| 264 | copy_bytes = sg->length - copy_bytes; |
| 265 | |
| 266 | (*iov)->iov_len = copy_bytes; |
| 267 | (*iov)->iov_base = (void __user *) udev->data_off + |
| 268 | udev->data_head; |
| 269 | |
| 270 | if (copy_data) { |
| 271 | to = (void *) udev->mb_addr + |
| 272 | udev->data_off + udev->data_head; |
| 273 | memcpy(to, from, copy_bytes); |
| 274 | tcmu_flush_dcache_range(to, copy_bytes); |
| 275 | } |
| 276 | |
| 277 | (*iov_cnt)++; |
| 278 | (*iov)++; |
| 279 | |
| 280 | UPDATE_HEAD(udev->data_head, |
| 281 | copy_bytes, udev->data_size); |
| 282 | } |
| 283 | |
| 284 | kunmap_atomic(from); |
| 285 | } |
| 286 | } |
| 287 | |
| 288 | static void gather_and_free_data_area(struct tcmu_dev *udev, |
| 289 | struct scatterlist *data_sg, unsigned int data_nents) |
| 290 | { |
| 291 | int i; |
| 292 | void *from, *to; |
| 293 | size_t copy_bytes; |
| 294 | struct scatterlist *sg; |
| 295 | |
| 296 | /* It'd be easier to look at entry's iovec again, but UAM */ |
| 297 | for_each_sg(data_sg, sg, data_nents, i) { |
| 298 | copy_bytes = min_t(size_t, sg->length, |
| 299 | head_to_end(udev->data_tail, udev->data_size)); |
| 300 | |
| 301 | to = kmap_atomic(sg_page(sg)) + sg->offset; |
| 302 | WARN_ON(sg->length + sg->offset > PAGE_SIZE); |
| 303 | from = (void *) udev->mb_addr + |
| 304 | udev->data_off + udev->data_tail; |
| 305 | tcmu_flush_dcache_range(from, copy_bytes); |
| 306 | memcpy(to, from, copy_bytes); |
| 307 | |
| 308 | UPDATE_HEAD(udev->data_tail, copy_bytes, udev->data_size); |
| 309 | |
| 310 | /* Uh oh, wrapped the data buffer for this sg's data */ |
| 311 | if (sg->length != copy_bytes) { |
| 312 | from = (void *) udev->mb_addr + |
| 313 | udev->data_off + udev->data_tail; |
| 314 | WARN_ON(udev->data_tail); |
| 315 | to += copy_bytes; |
| 316 | copy_bytes = sg->length - copy_bytes; |
| 317 | tcmu_flush_dcache_range(from, copy_bytes); |
| 318 | memcpy(to, from, copy_bytes); |
| 319 | |
| 320 | UPDATE_HEAD(udev->data_tail, |
| 321 | copy_bytes, udev->data_size); |
| 322 | } |
| 323 | kunmap_atomic(to); |
| 324 | } |
| 325 | } |
| 326 | |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 327 | /* |
Ilias Tsitsimpis | f97ec7d | 2015-04-23 21:47:00 +0300 | [diff] [blame] | 328 | * We can't queue a command until we have space available on the cmd ring *and* |
| 329 | * space available on the data ring. |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 330 | * |
| 331 | * Called with ring lock held. |
| 332 | */ |
Andy Grover | f56574a | 2014-10-02 10:23:15 -0700 | [diff] [blame] | 333 | static bool is_ring_space_avail(struct tcmu_dev *udev, size_t cmd_size, size_t data_needed) |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 334 | { |
| 335 | struct tcmu_mailbox *mb = udev->mb_addr; |
| 336 | size_t space; |
| 337 | u32 cmd_head; |
Andy Grover | f56574a | 2014-10-02 10:23:15 -0700 | [diff] [blame] | 338 | size_t cmd_needed; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 339 | |
| 340 | tcmu_flush_dcache_range(mb, sizeof(*mb)); |
| 341 | |
| 342 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ |
| 343 | |
Andy Grover | f56574a | 2014-10-02 10:23:15 -0700 | [diff] [blame] | 344 | /* |
| 345 | * If cmd end-of-ring space is too small then we need space for a NOP plus |
| 346 | * original cmd - cmds are internally contiguous. |
| 347 | */ |
| 348 | if (head_to_end(cmd_head, udev->cmdr_size) >= cmd_size) |
| 349 | cmd_needed = cmd_size; |
| 350 | else |
| 351 | cmd_needed = cmd_size + head_to_end(cmd_head, udev->cmdr_size); |
| 352 | |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 353 | space = spc_free(cmd_head, udev->cmdr_last_cleaned, udev->cmdr_size); |
| 354 | if (space < cmd_needed) { |
| 355 | pr_debug("no cmd space: %u %u %u\n", cmd_head, |
| 356 | udev->cmdr_last_cleaned, udev->cmdr_size); |
| 357 | return false; |
| 358 | } |
| 359 | |
| 360 | space = spc_free(udev->data_head, udev->data_tail, udev->data_size); |
| 361 | if (space < data_needed) { |
| 362 | pr_debug("no data space: %zu %zu %zu\n", udev->data_head, |
| 363 | udev->data_tail, udev->data_size); |
| 364 | return false; |
| 365 | } |
| 366 | |
| 367 | return true; |
| 368 | } |
| 369 | |
| 370 | static int tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd) |
| 371 | { |
| 372 | struct tcmu_dev *udev = tcmu_cmd->tcmu_dev; |
| 373 | struct se_cmd *se_cmd = tcmu_cmd->se_cmd; |
| 374 | size_t base_command_size, command_size; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 375 | struct tcmu_mailbox *mb; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 376 | struct tcmu_cmd_entry *entry; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 377 | struct iovec *iov; |
Ilias Tsitsimpis | f97ec7d | 2015-04-23 21:47:00 +0300 | [diff] [blame] | 378 | int iov_cnt; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 379 | uint32_t cmd_head; |
| 380 | uint64_t cdb_off; |
Ilias Tsitsimpis | f97ec7d | 2015-04-23 21:47:00 +0300 | [diff] [blame] | 381 | bool copy_to_data_area; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 382 | |
| 383 | if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) |
| 384 | return -EINVAL; |
| 385 | |
| 386 | /* |
| 387 | * Must be a certain minimum size for response sense info, but |
| 388 | * also may be larger if the iov array is large. |
| 389 | * |
| 390 | * iovs = sgl_nents+1, for end-of-ring case, plus another 1 |
| 391 | * b/c size == offsetof one-past-element. |
| 392 | */ |
| 393 | base_command_size = max(offsetof(struct tcmu_cmd_entry, |
Ilias Tsitsimpis | e4648b0 | 2015-04-23 21:30:09 +0300 | [diff] [blame] | 394 | req.iov[se_cmd->t_bidi_data_nents + |
| 395 | se_cmd->t_data_nents + 2]), |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 396 | sizeof(struct tcmu_cmd_entry)); |
| 397 | command_size = base_command_size |
| 398 | + round_up(scsi_command_size(se_cmd->t_task_cdb), TCMU_OP_ALIGN_SIZE); |
| 399 | |
| 400 | WARN_ON(command_size & (TCMU_OP_ALIGN_SIZE-1)); |
| 401 | |
| 402 | spin_lock_irq(&udev->cmdr_lock); |
| 403 | |
| 404 | mb = udev->mb_addr; |
| 405 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ |
| 406 | if ((command_size > (udev->cmdr_size / 2)) |
| 407 | || tcmu_cmd->data_length > (udev->data_size - 1)) |
| 408 | pr_warn("TCMU: Request of size %zu/%zu may be too big for %u/%zu " |
| 409 | "cmd/data ring buffers\n", command_size, tcmu_cmd->data_length, |
| 410 | udev->cmdr_size, udev->data_size); |
| 411 | |
Andy Grover | f56574a | 2014-10-02 10:23:15 -0700 | [diff] [blame] | 412 | while (!is_ring_space_avail(udev, command_size, tcmu_cmd->data_length)) { |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 413 | int ret; |
| 414 | DEFINE_WAIT(__wait); |
| 415 | |
| 416 | prepare_to_wait(&udev->wait_cmdr, &__wait, TASK_INTERRUPTIBLE); |
| 417 | |
| 418 | pr_debug("sleeping for ring space\n"); |
| 419 | spin_unlock_irq(&udev->cmdr_lock); |
| 420 | ret = schedule_timeout(msecs_to_jiffies(TCMU_TIME_OUT)); |
| 421 | finish_wait(&udev->wait_cmdr, &__wait); |
| 422 | if (!ret) { |
| 423 | pr_warn("tcmu: command timed out\n"); |
| 424 | return -ETIMEDOUT; |
| 425 | } |
| 426 | |
| 427 | spin_lock_irq(&udev->cmdr_lock); |
| 428 | |
| 429 | /* We dropped cmdr_lock, cmd_head is stale */ |
| 430 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ |
| 431 | } |
| 432 | |
Andy Grover | f56574a | 2014-10-02 10:23:15 -0700 | [diff] [blame] | 433 | /* Insert a PAD if end-of-ring space is too small */ |
| 434 | if (head_to_end(cmd_head, udev->cmdr_size) < command_size) { |
| 435 | size_t pad_size = head_to_end(cmd_head, udev->cmdr_size); |
| 436 | |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 437 | entry = (void *) mb + CMDR_OFF + cmd_head; |
| 438 | tcmu_flush_dcache_range(entry, sizeof(*entry)); |
Andy Grover | 0ad46af | 2015-04-14 17:30:04 -0700 | [diff] [blame] | 439 | tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_PAD); |
| 440 | tcmu_hdr_set_len(&entry->hdr.len_op, pad_size); |
| 441 | entry->hdr.cmd_id = 0; /* not used for PAD */ |
| 442 | entry->hdr.kflags = 0; |
| 443 | entry->hdr.uflags = 0; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 444 | |
| 445 | UPDATE_HEAD(mb->cmd_head, pad_size, udev->cmdr_size); |
| 446 | |
| 447 | cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */ |
| 448 | WARN_ON(cmd_head != 0); |
| 449 | } |
| 450 | |
| 451 | entry = (void *) mb + CMDR_OFF + cmd_head; |
| 452 | tcmu_flush_dcache_range(entry, sizeof(*entry)); |
Andy Grover | 0ad46af | 2015-04-14 17:30:04 -0700 | [diff] [blame] | 453 | tcmu_hdr_set_op(&entry->hdr.len_op, TCMU_OP_CMD); |
| 454 | tcmu_hdr_set_len(&entry->hdr.len_op, command_size); |
| 455 | entry->hdr.cmd_id = tcmu_cmd->cmd_id; |
| 456 | entry->hdr.kflags = 0; |
| 457 | entry->hdr.uflags = 0; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 458 | |
| 459 | /* |
| 460 | * Fix up iovecs, and handle if allocation in data ring wrapped. |
| 461 | */ |
| 462 | iov = &entry->req.iov[0]; |
Ilias Tsitsimpis | f97ec7d | 2015-04-23 21:47:00 +0300 | [diff] [blame] | 463 | iov_cnt = 0; |
Ilias Tsitsimpis | e4648b0 | 2015-04-23 21:30:09 +0300 | [diff] [blame] | 464 | copy_to_data_area = (se_cmd->data_direction == DMA_TO_DEVICE |
| 465 | || se_cmd->se_cmd_flags & SCF_BIDI); |
Ilias Tsitsimpis | f97ec7d | 2015-04-23 21:47:00 +0300 | [diff] [blame] | 466 | alloc_and_scatter_data_area(udev, se_cmd->t_data_sg, |
| 467 | se_cmd->t_data_nents, &iov, &iov_cnt, copy_to_data_area); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 468 | entry->req.iov_cnt = iov_cnt; |
Andy Grover | 0ad46af | 2015-04-14 17:30:04 -0700 | [diff] [blame] | 469 | entry->req.iov_dif_cnt = 0; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 470 | |
Ilias Tsitsimpis | e4648b0 | 2015-04-23 21:30:09 +0300 | [diff] [blame] | 471 | /* Handle BIDI commands */ |
| 472 | iov_cnt = 0; |
| 473 | alloc_and_scatter_data_area(udev, se_cmd->t_bidi_data_sg, |
| 474 | se_cmd->t_bidi_data_nents, &iov, &iov_cnt, false); |
| 475 | entry->req.iov_bidi_cnt = iov_cnt; |
| 476 | |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 477 | /* All offsets relative to mb_addr, not start of entry! */ |
| 478 | cdb_off = CMDR_OFF + cmd_head + base_command_size; |
| 479 | memcpy((void *) mb + cdb_off, se_cmd->t_task_cdb, scsi_command_size(se_cmd->t_task_cdb)); |
| 480 | entry->req.cdb_off = cdb_off; |
| 481 | tcmu_flush_dcache_range(entry, sizeof(*entry)); |
| 482 | |
| 483 | UPDATE_HEAD(mb->cmd_head, command_size, udev->cmdr_size); |
| 484 | tcmu_flush_dcache_range(mb, sizeof(*mb)); |
| 485 | |
| 486 | spin_unlock_irq(&udev->cmdr_lock); |
| 487 | |
| 488 | /* TODO: only if FLUSH and FUA? */ |
| 489 | uio_event_notify(&udev->uio_info); |
| 490 | |
| 491 | mod_timer(&udev->timeout, |
| 492 | round_jiffies_up(jiffies + msecs_to_jiffies(TCMU_TIME_OUT))); |
| 493 | |
| 494 | return 0; |
| 495 | } |
| 496 | |
| 497 | static int tcmu_queue_cmd(struct se_cmd *se_cmd) |
| 498 | { |
| 499 | struct se_device *se_dev = se_cmd->se_dev; |
| 500 | struct tcmu_dev *udev = TCMU_DEV(se_dev); |
| 501 | struct tcmu_cmd *tcmu_cmd; |
| 502 | int ret; |
| 503 | |
| 504 | tcmu_cmd = tcmu_alloc_cmd(se_cmd); |
| 505 | if (!tcmu_cmd) |
| 506 | return -ENOMEM; |
| 507 | |
| 508 | ret = tcmu_queue_cmd_ring(tcmu_cmd); |
| 509 | if (ret < 0) { |
| 510 | pr_err("TCMU: Could not queue command\n"); |
| 511 | spin_lock_irq(&udev->commands_lock); |
| 512 | idr_remove(&udev->commands, tcmu_cmd->cmd_id); |
| 513 | spin_unlock_irq(&udev->commands_lock); |
| 514 | |
| 515 | kmem_cache_free(tcmu_cmd_cache, tcmu_cmd); |
| 516 | } |
| 517 | |
| 518 | return ret; |
| 519 | } |
| 520 | |
| 521 | static void tcmu_handle_completion(struct tcmu_cmd *cmd, struct tcmu_cmd_entry *entry) |
| 522 | { |
| 523 | struct se_cmd *se_cmd = cmd->se_cmd; |
| 524 | struct tcmu_dev *udev = cmd->tcmu_dev; |
| 525 | |
| 526 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) { |
| 527 | /* cmd has been completed already from timeout, just reclaim data |
| 528 | ring space */ |
| 529 | UPDATE_HEAD(udev->data_tail, cmd->data_length, udev->data_size); |
| 530 | return; |
| 531 | } |
| 532 | |
Andy Grover | 0ad46af | 2015-04-14 17:30:04 -0700 | [diff] [blame] | 533 | if (entry->hdr.uflags & TCMU_UFLAG_UNKNOWN_OP) { |
| 534 | UPDATE_HEAD(udev->data_tail, cmd->data_length, udev->data_size); |
| 535 | pr_warn("TCMU: Userspace set UNKNOWN_OP flag on se_cmd %p\n", |
| 536 | cmd->se_cmd); |
| 537 | transport_generic_request_failure(cmd->se_cmd, |
| 538 | TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE); |
| 539 | cmd->se_cmd = NULL; |
| 540 | kmem_cache_free(tcmu_cmd_cache, cmd); |
| 541 | return; |
| 542 | } |
| 543 | |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 544 | if (entry->rsp.scsi_status == SAM_STAT_CHECK_CONDITION) { |
| 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); |
Ilias Tsitsimpis | e4648b0 | 2015-04-23 21:30:09 +0300 | [diff] [blame] | 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) { |
Ilias Tsitsimpis | f97ec7d | 2015-04-23 21:47:00 +0300 | [diff] [blame] | 558 | gather_and_free_data_area(udev, |
| 559 | se_cmd->t_data_sg, se_cmd->t_data_nents); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 560 | } else if (se_cmd->data_direction == DMA_TO_DEVICE) { |
| 561 | UPDATE_HEAD(udev->data_tail, cmd->data_length, udev->data_size); |
Ilias Tsitsimpis | 2bc396a | 2015-04-23 21:30:05 +0300 | [diff] [blame] | 562 | } else if (se_cmd->data_direction != DMA_NONE) { |
| 563 | pr_warn("TCMU: data direction was %d!\n", |
| 564 | se_cmd->data_direction); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 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; |
| 576 | LIST_HEAD(cpl_cmds); |
| 577 | unsigned long flags; |
| 578 | int handled = 0; |
| 579 | |
| 580 | if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags)) { |
| 581 | pr_err("ring broken, not handling completions\n"); |
| 582 | return 0; |
| 583 | } |
| 584 | |
| 585 | spin_lock_irqsave(&udev->cmdr_lock, flags); |
| 586 | |
| 587 | mb = udev->mb_addr; |
| 588 | tcmu_flush_dcache_range(mb, sizeof(*mb)); |
| 589 | |
| 590 | while (udev->cmdr_last_cleaned != ACCESS_ONCE(mb->cmd_tail)) { |
| 591 | |
| 592 | struct tcmu_cmd_entry *entry = (void *) mb + CMDR_OFF + udev->cmdr_last_cleaned; |
| 593 | struct tcmu_cmd *cmd; |
| 594 | |
| 595 | tcmu_flush_dcache_range(entry, sizeof(*entry)); |
| 596 | |
Andy Grover | 0ad46af | 2015-04-14 17:30:04 -0700 | [diff] [blame] | 597 | if (tcmu_hdr_get_op(entry->hdr.len_op) == TCMU_OP_PAD) { |
| 598 | UPDATE_HEAD(udev->cmdr_last_cleaned, |
| 599 | tcmu_hdr_get_len(entry->hdr.len_op), |
| 600 | udev->cmdr_size); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 601 | continue; |
| 602 | } |
Andy Grover | 0ad46af | 2015-04-14 17:30:04 -0700 | [diff] [blame] | 603 | WARN_ON(tcmu_hdr_get_op(entry->hdr.len_op) != TCMU_OP_CMD); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 604 | |
| 605 | spin_lock(&udev->commands_lock); |
Andy Grover | 0ad46af | 2015-04-14 17:30:04 -0700 | [diff] [blame] | 606 | cmd = idr_find(&udev->commands, entry->hdr.cmd_id); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 607 | if (cmd) |
| 608 | idr_remove(&udev->commands, cmd->cmd_id); |
| 609 | spin_unlock(&udev->commands_lock); |
| 610 | |
| 611 | if (!cmd) { |
| 612 | pr_err("cmd_id not found, ring is broken\n"); |
| 613 | set_bit(TCMU_DEV_BIT_BROKEN, &udev->flags); |
| 614 | break; |
| 615 | } |
| 616 | |
| 617 | tcmu_handle_completion(cmd, entry); |
| 618 | |
Andy Grover | 0ad46af | 2015-04-14 17:30:04 -0700 | [diff] [blame] | 619 | UPDATE_HEAD(udev->cmdr_last_cleaned, |
| 620 | tcmu_hdr_get_len(entry->hdr.len_op), |
| 621 | udev->cmdr_size); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 622 | |
| 623 | handled++; |
| 624 | } |
| 625 | |
| 626 | if (mb->cmd_tail == mb->cmd_head) |
| 627 | del_timer(&udev->timeout); /* no more pending cmds */ |
| 628 | |
| 629 | spin_unlock_irqrestore(&udev->cmdr_lock, flags); |
| 630 | |
| 631 | wake_up(&udev->wait_cmdr); |
| 632 | |
| 633 | return handled; |
| 634 | } |
| 635 | |
| 636 | static int tcmu_check_expired_cmd(int id, void *p, void *data) |
| 637 | { |
| 638 | struct tcmu_cmd *cmd = p; |
| 639 | |
| 640 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) |
| 641 | return 0; |
| 642 | |
| 643 | if (!time_after(cmd->deadline, jiffies)) |
| 644 | return 0; |
| 645 | |
| 646 | set_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags); |
| 647 | target_complete_cmd(cmd->se_cmd, SAM_STAT_CHECK_CONDITION); |
| 648 | cmd->se_cmd = NULL; |
| 649 | |
| 650 | kmem_cache_free(tcmu_cmd_cache, cmd); |
| 651 | |
| 652 | return 0; |
| 653 | } |
| 654 | |
| 655 | static void tcmu_device_timedout(unsigned long data) |
| 656 | { |
| 657 | struct tcmu_dev *udev = (struct tcmu_dev *)data; |
| 658 | unsigned long flags; |
| 659 | int handled; |
| 660 | |
| 661 | handled = tcmu_handle_completions(udev); |
| 662 | |
| 663 | pr_warn("%d completions handled from timeout\n", handled); |
| 664 | |
| 665 | spin_lock_irqsave(&udev->commands_lock, flags); |
| 666 | idr_for_each(&udev->commands, tcmu_check_expired_cmd, NULL); |
| 667 | spin_unlock_irqrestore(&udev->commands_lock, flags); |
| 668 | |
| 669 | /* |
| 670 | * We don't need to wakeup threads on wait_cmdr since they have their |
| 671 | * own timeout. |
| 672 | */ |
| 673 | } |
| 674 | |
| 675 | static int tcmu_attach_hba(struct se_hba *hba, u32 host_id) |
| 676 | { |
| 677 | struct tcmu_hba *tcmu_hba; |
| 678 | |
| 679 | tcmu_hba = kzalloc(sizeof(struct tcmu_hba), GFP_KERNEL); |
| 680 | if (!tcmu_hba) |
| 681 | return -ENOMEM; |
| 682 | |
| 683 | tcmu_hba->host_id = host_id; |
| 684 | hba->hba_ptr = tcmu_hba; |
| 685 | |
| 686 | return 0; |
| 687 | } |
| 688 | |
| 689 | static void tcmu_detach_hba(struct se_hba *hba) |
| 690 | { |
| 691 | kfree(hba->hba_ptr); |
| 692 | hba->hba_ptr = NULL; |
| 693 | } |
| 694 | |
| 695 | static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name) |
| 696 | { |
| 697 | struct tcmu_dev *udev; |
| 698 | |
| 699 | udev = kzalloc(sizeof(struct tcmu_dev), GFP_KERNEL); |
| 700 | if (!udev) |
| 701 | return NULL; |
| 702 | |
| 703 | udev->name = kstrdup(name, GFP_KERNEL); |
| 704 | if (!udev->name) { |
| 705 | kfree(udev); |
| 706 | return NULL; |
| 707 | } |
| 708 | |
| 709 | udev->hba = hba; |
| 710 | |
| 711 | init_waitqueue_head(&udev->wait_cmdr); |
| 712 | spin_lock_init(&udev->cmdr_lock); |
| 713 | |
| 714 | idr_init(&udev->commands); |
| 715 | spin_lock_init(&udev->commands_lock); |
| 716 | |
| 717 | setup_timer(&udev->timeout, tcmu_device_timedout, |
| 718 | (unsigned long)udev); |
| 719 | |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 720 | return &udev->se_dev; |
| 721 | } |
| 722 | |
| 723 | static int tcmu_irqcontrol(struct uio_info *info, s32 irq_on) |
| 724 | { |
| 725 | struct tcmu_dev *tcmu_dev = container_of(info, struct tcmu_dev, uio_info); |
| 726 | |
| 727 | tcmu_handle_completions(tcmu_dev); |
| 728 | |
| 729 | return 0; |
| 730 | } |
| 731 | |
| 732 | /* |
| 733 | * mmap code from uio.c. Copied here because we want to hook mmap() |
| 734 | * and this stuff must come along. |
| 735 | */ |
| 736 | static int tcmu_find_mem_index(struct vm_area_struct *vma) |
| 737 | { |
| 738 | struct tcmu_dev *udev = vma->vm_private_data; |
| 739 | struct uio_info *info = &udev->uio_info; |
| 740 | |
| 741 | if (vma->vm_pgoff < MAX_UIO_MAPS) { |
| 742 | if (info->mem[vma->vm_pgoff].size == 0) |
| 743 | return -1; |
| 744 | return (int)vma->vm_pgoff; |
| 745 | } |
| 746 | return -1; |
| 747 | } |
| 748 | |
| 749 | static int tcmu_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
| 750 | { |
| 751 | struct tcmu_dev *udev = vma->vm_private_data; |
| 752 | struct uio_info *info = &udev->uio_info; |
| 753 | struct page *page; |
| 754 | unsigned long offset; |
| 755 | void *addr; |
| 756 | |
| 757 | int mi = tcmu_find_mem_index(vma); |
| 758 | if (mi < 0) |
| 759 | return VM_FAULT_SIGBUS; |
| 760 | |
| 761 | /* |
| 762 | * We need to subtract mi because userspace uses offset = N*PAGE_SIZE |
| 763 | * to use mem[N]. |
| 764 | */ |
| 765 | offset = (vmf->pgoff - mi) << PAGE_SHIFT; |
| 766 | |
| 767 | addr = (void *)(unsigned long)info->mem[mi].addr + offset; |
| 768 | if (info->mem[mi].memtype == UIO_MEM_LOGICAL) |
| 769 | page = virt_to_page(addr); |
| 770 | else |
| 771 | page = vmalloc_to_page(addr); |
| 772 | get_page(page); |
| 773 | vmf->page = page; |
| 774 | return 0; |
| 775 | } |
| 776 | |
| 777 | static const struct vm_operations_struct tcmu_vm_ops = { |
| 778 | .fault = tcmu_vma_fault, |
| 779 | }; |
| 780 | |
| 781 | static int tcmu_mmap(struct uio_info *info, struct vm_area_struct *vma) |
| 782 | { |
| 783 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); |
| 784 | |
| 785 | vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; |
| 786 | vma->vm_ops = &tcmu_vm_ops; |
| 787 | |
| 788 | vma->vm_private_data = udev; |
| 789 | |
| 790 | /* Ensure the mmap is exactly the right size */ |
| 791 | if (vma_pages(vma) != (TCMU_RING_SIZE >> PAGE_SHIFT)) |
| 792 | return -EINVAL; |
| 793 | |
| 794 | return 0; |
| 795 | } |
| 796 | |
| 797 | static int tcmu_open(struct uio_info *info, struct inode *inode) |
| 798 | { |
| 799 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); |
| 800 | |
| 801 | /* O_EXCL not supported for char devs, so fake it? */ |
| 802 | if (test_and_set_bit(TCMU_DEV_BIT_OPEN, &udev->flags)) |
| 803 | return -EBUSY; |
| 804 | |
| 805 | pr_debug("open\n"); |
| 806 | |
| 807 | return 0; |
| 808 | } |
| 809 | |
| 810 | static int tcmu_release(struct uio_info *info, struct inode *inode) |
| 811 | { |
| 812 | struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info); |
| 813 | |
| 814 | clear_bit(TCMU_DEV_BIT_OPEN, &udev->flags); |
| 815 | |
| 816 | pr_debug("close\n"); |
| 817 | |
| 818 | return 0; |
| 819 | } |
| 820 | |
| 821 | static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name, int minor) |
| 822 | { |
| 823 | struct sk_buff *skb; |
| 824 | void *msg_header; |
Nicholas Bellinger | 6e14eab | 2014-10-01 23:01:15 -0700 | [diff] [blame] | 825 | int ret = -ENOMEM; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 826 | |
| 827 | skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); |
| 828 | if (!skb) |
Nicholas Bellinger | 6e14eab | 2014-10-01 23:01:15 -0700 | [diff] [blame] | 829 | return ret; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 830 | |
| 831 | msg_header = genlmsg_put(skb, 0, 0, &tcmu_genl_family, 0, cmd); |
Nicholas Bellinger | 6e14eab | 2014-10-01 23:01:15 -0700 | [diff] [blame] | 832 | if (!msg_header) |
| 833 | goto free_skb; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 834 | |
| 835 | ret = nla_put_string(skb, TCMU_ATTR_DEVICE, name); |
Nicholas Bellinger | 6e14eab | 2014-10-01 23:01:15 -0700 | [diff] [blame] | 836 | if (ret < 0) |
| 837 | goto free_skb; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 838 | |
| 839 | ret = nla_put_u32(skb, TCMU_ATTR_MINOR, minor); |
Nicholas Bellinger | 6e14eab | 2014-10-01 23:01:15 -0700 | [diff] [blame] | 840 | if (ret < 0) |
| 841 | goto free_skb; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 842 | |
Johannes Berg | 053c095 | 2015-01-16 22:09:00 +0100 | [diff] [blame] | 843 | genlmsg_end(skb, msg_header); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 844 | |
| 845 | ret = genlmsg_multicast(&tcmu_genl_family, skb, 0, |
| 846 | TCMU_MCGRP_CONFIG, GFP_KERNEL); |
| 847 | |
| 848 | /* We don't care if no one is listening */ |
| 849 | if (ret == -ESRCH) |
| 850 | ret = 0; |
| 851 | |
| 852 | return ret; |
Nicholas Bellinger | 6e14eab | 2014-10-01 23:01:15 -0700 | [diff] [blame] | 853 | free_skb: |
| 854 | nlmsg_free(skb); |
| 855 | return ret; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 856 | } |
| 857 | |
| 858 | static int tcmu_configure_device(struct se_device *dev) |
| 859 | { |
| 860 | struct tcmu_dev *udev = TCMU_DEV(dev); |
| 861 | struct tcmu_hba *hba = udev->hba->hba_ptr; |
| 862 | struct uio_info *info; |
| 863 | struct tcmu_mailbox *mb; |
| 864 | size_t size; |
| 865 | size_t used; |
| 866 | int ret = 0; |
| 867 | char *str; |
| 868 | |
| 869 | info = &udev->uio_info; |
| 870 | |
| 871 | size = snprintf(NULL, 0, "tcm-user/%u/%s/%s", hba->host_id, udev->name, |
| 872 | udev->dev_config); |
| 873 | size += 1; /* for \0 */ |
| 874 | str = kmalloc(size, GFP_KERNEL); |
| 875 | if (!str) |
| 876 | return -ENOMEM; |
| 877 | |
| 878 | used = snprintf(str, size, "tcm-user/%u/%s", hba->host_id, udev->name); |
| 879 | |
| 880 | if (udev->dev_config[0]) |
| 881 | snprintf(str + used, size - used, "/%s", udev->dev_config); |
| 882 | |
| 883 | info->name = str; |
| 884 | |
| 885 | udev->mb_addr = vzalloc(TCMU_RING_SIZE); |
| 886 | if (!udev->mb_addr) { |
| 887 | ret = -ENOMEM; |
| 888 | goto err_vzalloc; |
| 889 | } |
| 890 | |
| 891 | /* mailbox fits in first part of CMDR space */ |
| 892 | udev->cmdr_size = CMDR_SIZE - CMDR_OFF; |
| 893 | udev->data_off = CMDR_SIZE; |
| 894 | udev->data_size = TCMU_RING_SIZE - CMDR_SIZE; |
| 895 | |
| 896 | mb = udev->mb_addr; |
Andy Grover | 0ad46af | 2015-04-14 17:30:04 -0700 | [diff] [blame] | 897 | mb->version = TCMU_MAILBOX_VERSION; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 898 | mb->cmdr_off = CMDR_OFF; |
| 899 | mb->cmdr_size = udev->cmdr_size; |
| 900 | |
| 901 | WARN_ON(!PAGE_ALIGNED(udev->data_off)); |
| 902 | WARN_ON(udev->data_size % PAGE_SIZE); |
| 903 | |
Andy Grover | 0ad46af | 2015-04-14 17:30:04 -0700 | [diff] [blame] | 904 | info->version = xstr(TCMU_MAILBOX_VERSION); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 905 | |
| 906 | info->mem[0].name = "tcm-user command & data buffer"; |
| 907 | info->mem[0].addr = (phys_addr_t) udev->mb_addr; |
| 908 | info->mem[0].size = TCMU_RING_SIZE; |
| 909 | info->mem[0].memtype = UIO_MEM_VIRTUAL; |
| 910 | |
| 911 | info->irqcontrol = tcmu_irqcontrol; |
| 912 | info->irq = UIO_IRQ_CUSTOM; |
| 913 | |
| 914 | info->mmap = tcmu_mmap; |
| 915 | info->open = tcmu_open; |
| 916 | info->release = tcmu_release; |
| 917 | |
| 918 | ret = uio_register_device(tcmu_root_device, info); |
| 919 | if (ret) |
| 920 | goto err_register; |
| 921 | |
| 922 | /* Other attributes can be configured in userspace */ |
| 923 | dev->dev_attrib.hw_block_size = 512; |
| 924 | dev->dev_attrib.hw_max_sectors = 128; |
| 925 | dev->dev_attrib.hw_queue_depth = 128; |
| 926 | |
| 927 | ret = tcmu_netlink_event(TCMU_CMD_ADDED_DEVICE, udev->uio_info.name, |
| 928 | udev->uio_info.uio_dev->minor); |
| 929 | if (ret) |
| 930 | goto err_netlink; |
| 931 | |
| 932 | return 0; |
| 933 | |
| 934 | err_netlink: |
| 935 | uio_unregister_device(&udev->uio_info); |
| 936 | err_register: |
| 937 | vfree(udev->mb_addr); |
| 938 | err_vzalloc: |
| 939 | kfree(info->name); |
| 940 | |
| 941 | return ret; |
| 942 | } |
| 943 | |
| 944 | static int tcmu_check_pending_cmd(int id, void *p, void *data) |
| 945 | { |
| 946 | struct tcmu_cmd *cmd = p; |
| 947 | |
| 948 | if (test_bit(TCMU_CMD_BIT_EXPIRED, &cmd->flags)) |
| 949 | return 0; |
| 950 | return -EINVAL; |
| 951 | } |
| 952 | |
Nicholas Bellinger | 4cc987e | 2015-05-19 00:03:07 -0700 | [diff] [blame^] | 953 | static void tcmu_dev_call_rcu(struct rcu_head *p) |
| 954 | { |
| 955 | struct se_device *dev = container_of(p, struct se_device, rcu_head); |
| 956 | struct tcmu_dev *udev = TCMU_DEV(dev); |
| 957 | |
| 958 | kfree(udev); |
| 959 | } |
| 960 | |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 961 | static void tcmu_free_device(struct se_device *dev) |
| 962 | { |
| 963 | struct tcmu_dev *udev = TCMU_DEV(dev); |
| 964 | int i; |
| 965 | |
| 966 | del_timer_sync(&udev->timeout); |
| 967 | |
| 968 | vfree(udev->mb_addr); |
| 969 | |
| 970 | /* Upper layer should drain all requests before calling this */ |
| 971 | spin_lock_irq(&udev->commands_lock); |
| 972 | i = idr_for_each(&udev->commands, tcmu_check_pending_cmd, NULL); |
| 973 | idr_destroy(&udev->commands); |
| 974 | spin_unlock_irq(&udev->commands_lock); |
| 975 | WARN_ON(i); |
| 976 | |
| 977 | /* Device was configured */ |
| 978 | if (udev->uio_info.uio_dev) { |
| 979 | tcmu_netlink_event(TCMU_CMD_REMOVED_DEVICE, udev->uio_info.name, |
| 980 | udev->uio_info.uio_dev->minor); |
| 981 | |
| 982 | uio_unregister_device(&udev->uio_info); |
| 983 | kfree(udev->uio_info.name); |
| 984 | kfree(udev->name); |
| 985 | } |
Nicholas Bellinger | 4cc987e | 2015-05-19 00:03:07 -0700 | [diff] [blame^] | 986 | call_rcu(&dev->rcu_head, tcmu_dev_call_rcu); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 987 | } |
| 988 | |
| 989 | enum { |
Andy Grover | 9c1cd1b | 2015-05-19 14:44:39 -0700 | [diff] [blame] | 990 | Opt_dev_config, Opt_dev_size, Opt_hw_block_size, Opt_err, |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 991 | }; |
| 992 | |
| 993 | static match_table_t tokens = { |
| 994 | {Opt_dev_config, "dev_config=%s"}, |
| 995 | {Opt_dev_size, "dev_size=%u"}, |
Andy Grover | 9c1cd1b | 2015-05-19 14:44:39 -0700 | [diff] [blame] | 996 | {Opt_hw_block_size, "hw_block_size=%u"}, |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 997 | {Opt_err, NULL} |
| 998 | }; |
| 999 | |
| 1000 | static ssize_t tcmu_set_configfs_dev_params(struct se_device *dev, |
| 1001 | const char *page, ssize_t count) |
| 1002 | { |
| 1003 | struct tcmu_dev *udev = TCMU_DEV(dev); |
| 1004 | char *orig, *ptr, *opts, *arg_p; |
| 1005 | substring_t args[MAX_OPT_ARGS]; |
| 1006 | int ret = 0, token; |
Andy Grover | 9c1cd1b | 2015-05-19 14:44:39 -0700 | [diff] [blame] | 1007 | unsigned long tmp_ul; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1008 | |
| 1009 | opts = kstrdup(page, GFP_KERNEL); |
| 1010 | if (!opts) |
| 1011 | return -ENOMEM; |
| 1012 | |
| 1013 | orig = opts; |
| 1014 | |
| 1015 | while ((ptr = strsep(&opts, ",\n")) != NULL) { |
| 1016 | if (!*ptr) |
| 1017 | continue; |
| 1018 | |
| 1019 | token = match_token(ptr, tokens, args); |
| 1020 | switch (token) { |
| 1021 | case Opt_dev_config: |
| 1022 | if (match_strlcpy(udev->dev_config, &args[0], |
| 1023 | TCMU_CONFIG_LEN) == 0) { |
| 1024 | ret = -EINVAL; |
| 1025 | break; |
| 1026 | } |
| 1027 | pr_debug("TCMU: Referencing Path: %s\n", udev->dev_config); |
| 1028 | break; |
| 1029 | case Opt_dev_size: |
| 1030 | arg_p = match_strdup(&args[0]); |
| 1031 | if (!arg_p) { |
| 1032 | ret = -ENOMEM; |
| 1033 | break; |
| 1034 | } |
| 1035 | ret = kstrtoul(arg_p, 0, (unsigned long *) &udev->dev_size); |
| 1036 | kfree(arg_p); |
| 1037 | if (ret < 0) |
| 1038 | pr_err("kstrtoul() failed for dev_size=\n"); |
| 1039 | break; |
Andy Grover | 9c1cd1b | 2015-05-19 14:44:39 -0700 | [diff] [blame] | 1040 | case Opt_hw_block_size: |
| 1041 | arg_p = match_strdup(&args[0]); |
| 1042 | if (!arg_p) { |
| 1043 | ret = -ENOMEM; |
| 1044 | break; |
| 1045 | } |
| 1046 | ret = kstrtoul(arg_p, 0, &tmp_ul); |
| 1047 | kfree(arg_p); |
| 1048 | if (ret < 0) { |
| 1049 | pr_err("kstrtoul() failed for hw_block_size=\n"); |
| 1050 | break; |
| 1051 | } |
| 1052 | if (!tmp_ul) { |
| 1053 | pr_err("hw_block_size must be nonzero\n"); |
| 1054 | break; |
| 1055 | } |
| 1056 | dev->dev_attrib.hw_block_size = tmp_ul; |
| 1057 | break; |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1058 | default: |
| 1059 | break; |
| 1060 | } |
| 1061 | } |
| 1062 | |
| 1063 | kfree(orig); |
| 1064 | return (!ret) ? count : ret; |
| 1065 | } |
| 1066 | |
| 1067 | static ssize_t tcmu_show_configfs_dev_params(struct se_device *dev, char *b) |
| 1068 | { |
| 1069 | struct tcmu_dev *udev = TCMU_DEV(dev); |
| 1070 | ssize_t bl = 0; |
| 1071 | |
| 1072 | bl = sprintf(b + bl, "Config: %s ", |
| 1073 | udev->dev_config[0] ? udev->dev_config : "NULL"); |
Andy Grover | 8ee83a7 | 2015-05-01 10:43:45 -0700 | [diff] [blame] | 1074 | bl += sprintf(b + bl, "Size: %zu\n", udev->dev_size); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1075 | |
| 1076 | return bl; |
| 1077 | } |
| 1078 | |
| 1079 | static sector_t tcmu_get_blocks(struct se_device *dev) |
| 1080 | { |
| 1081 | struct tcmu_dev *udev = TCMU_DEV(dev); |
| 1082 | |
| 1083 | return div_u64(udev->dev_size - dev->dev_attrib.block_size, |
| 1084 | dev->dev_attrib.block_size); |
| 1085 | } |
| 1086 | |
| 1087 | static sense_reason_t |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1088 | tcmu_pass_op(struct se_cmd *se_cmd) |
| 1089 | { |
| 1090 | int ret = tcmu_queue_cmd(se_cmd); |
| 1091 | |
| 1092 | if (ret != 0) |
| 1093 | return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; |
| 1094 | else |
| 1095 | return TCM_NO_SENSE; |
| 1096 | } |
| 1097 | |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1098 | static sense_reason_t |
| 1099 | tcmu_parse_cdb(struct se_cmd *cmd) |
| 1100 | { |
Andy Grover | 7bfea53b | 2015-05-19 14:44:40 -0700 | [diff] [blame] | 1101 | return passthrough_parse_cdb(cmd, tcmu_pass_op); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1102 | } |
| 1103 | |
Christoph Hellwig | 0a06d43 | 2015-05-10 18:14:56 +0200 | [diff] [blame] | 1104 | static const struct target_backend_ops tcmu_ops = { |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1105 | .name = "user", |
| 1106 | .inquiry_prod = "USER", |
| 1107 | .inquiry_rev = TCMU_VERSION, |
| 1108 | .owner = THIS_MODULE, |
Andy Grover | a354170 | 2015-05-19 14:44:41 -0700 | [diff] [blame] | 1109 | .transport_flags = TRANSPORT_FLAG_PASSTHROUGH, |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1110 | .attach_hba = tcmu_attach_hba, |
| 1111 | .detach_hba = tcmu_detach_hba, |
| 1112 | .alloc_device = tcmu_alloc_device, |
| 1113 | .configure_device = tcmu_configure_device, |
| 1114 | .free_device = tcmu_free_device, |
| 1115 | .parse_cdb = tcmu_parse_cdb, |
| 1116 | .set_configfs_dev_params = tcmu_set_configfs_dev_params, |
| 1117 | .show_configfs_dev_params = tcmu_show_configfs_dev_params, |
| 1118 | .get_device_type = sbc_get_device_type, |
| 1119 | .get_blocks = tcmu_get_blocks, |
Christoph Hellwig | 5873c4d | 2015-05-10 18:14:57 +0200 | [diff] [blame] | 1120 | .tb_dev_attrib_attrs = passthrough_attrib_attrs, |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1121 | }; |
| 1122 | |
| 1123 | static int __init tcmu_module_init(void) |
| 1124 | { |
| 1125 | int ret; |
| 1126 | |
| 1127 | BUILD_BUG_ON((sizeof(struct tcmu_cmd_entry) % TCMU_OP_ALIGN_SIZE) != 0); |
| 1128 | |
| 1129 | tcmu_cmd_cache = kmem_cache_create("tcmu_cmd_cache", |
| 1130 | sizeof(struct tcmu_cmd), |
| 1131 | __alignof__(struct tcmu_cmd), |
| 1132 | 0, NULL); |
| 1133 | if (!tcmu_cmd_cache) |
| 1134 | return -ENOMEM; |
| 1135 | |
| 1136 | tcmu_root_device = root_device_register("tcm_user"); |
| 1137 | if (IS_ERR(tcmu_root_device)) { |
| 1138 | ret = PTR_ERR(tcmu_root_device); |
| 1139 | goto out_free_cache; |
| 1140 | } |
| 1141 | |
| 1142 | ret = genl_register_family(&tcmu_genl_family); |
| 1143 | if (ret < 0) { |
| 1144 | goto out_unreg_device; |
| 1145 | } |
| 1146 | |
Christoph Hellwig | 0a06d43 | 2015-05-10 18:14:56 +0200 | [diff] [blame] | 1147 | ret = transport_backend_register(&tcmu_ops); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1148 | if (ret) |
| 1149 | goto out_unreg_genl; |
| 1150 | |
| 1151 | return 0; |
| 1152 | |
| 1153 | out_unreg_genl: |
| 1154 | genl_unregister_family(&tcmu_genl_family); |
| 1155 | out_unreg_device: |
| 1156 | root_device_unregister(tcmu_root_device); |
| 1157 | out_free_cache: |
| 1158 | kmem_cache_destroy(tcmu_cmd_cache); |
| 1159 | |
| 1160 | return ret; |
| 1161 | } |
| 1162 | |
| 1163 | static void __exit tcmu_module_exit(void) |
| 1164 | { |
Christoph Hellwig | 0a06d43 | 2015-05-10 18:14:56 +0200 | [diff] [blame] | 1165 | target_backend_unregister(&tcmu_ops); |
Andy Grover | 7c9e7a6 | 2014-10-01 16:07:05 -0700 | [diff] [blame] | 1166 | genl_unregister_family(&tcmu_genl_family); |
| 1167 | root_device_unregister(tcmu_root_device); |
| 1168 | kmem_cache_destroy(tcmu_cmd_cache); |
| 1169 | } |
| 1170 | |
| 1171 | MODULE_DESCRIPTION("TCM USER subsystem plugin"); |
| 1172 | MODULE_AUTHOR("Shaohua Li <shli@kernel.org>"); |
| 1173 | MODULE_AUTHOR("Andy Grover <agrover@redhat.com>"); |
| 1174 | MODULE_LICENSE("GPL"); |
| 1175 | |
| 1176 | module_init(tcmu_module_init); |
| 1177 | module_exit(tcmu_module_exit); |