FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 1 | /* |
| 2 | * SCSI target kernel/user interface functions |
| 3 | * |
| 4 | * Copyright (C) 2005 FUJITA Tomonori <tomof@acm.org> |
| 5 | * Copyright (C) 2005 Mike Christie <michaelc@cs.wisc.edu> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License as |
| 9 | * published by the Free Software Foundation; either version 2 of the |
| 10 | * License, or (at your option) any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, but |
| 13 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA |
| 20 | * 02110-1301 USA |
| 21 | */ |
| 22 | #include <linux/miscdevice.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 23 | #include <linux/gfp.h> |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 24 | #include <linux/file.h> |
Paul Gortmaker | 0970366 | 2011-05-27 09:37:25 -0400 | [diff] [blame^] | 25 | #include <linux/export.h> |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 26 | #include <net/tcp.h> |
| 27 | #include <scsi/scsi.h> |
| 28 | #include <scsi/scsi_cmnd.h> |
| 29 | #include <scsi/scsi_device.h> |
| 30 | #include <scsi/scsi_host.h> |
| 31 | #include <scsi/scsi_tgt.h> |
| 32 | #include <scsi/scsi_tgt_if.h> |
| 33 | |
akpm@osdl.org | e42ebef | 2006-12-04 23:06:48 -0800 | [diff] [blame] | 34 | #include <asm/cacheflush.h> |
| 35 | |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 36 | #include "scsi_tgt_priv.h" |
| 37 | |
FUJITA Tomonori | 930e99b | 2007-02-13 23:21:52 +0900 | [diff] [blame] | 38 | #if TGT_RING_SIZE < PAGE_SIZE |
| 39 | # define TGT_RING_SIZE PAGE_SIZE |
| 40 | #endif |
| 41 | |
| 42 | #define TGT_RING_PAGES (TGT_RING_SIZE >> PAGE_SHIFT) |
| 43 | #define TGT_EVENT_PER_PAGE (PAGE_SIZE / sizeof(struct tgt_event)) |
| 44 | #define TGT_MAX_EVENTS (TGT_EVENT_PER_PAGE * TGT_RING_PAGES) |
| 45 | |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 46 | struct tgt_ring { |
| 47 | u32 tr_idx; |
| 48 | unsigned long tr_pages[TGT_RING_PAGES]; |
| 49 | spinlock_t tr_lock; |
| 50 | }; |
| 51 | |
| 52 | /* tx_ring : kernel->user, rx_ring : user->kernel */ |
| 53 | static struct tgt_ring tx_ring, rx_ring; |
| 54 | static DECLARE_WAIT_QUEUE_HEAD(tgt_poll_wait); |
| 55 | |
| 56 | static inline void tgt_ring_idx_inc(struct tgt_ring *ring) |
| 57 | { |
| 58 | if (ring->tr_idx == TGT_MAX_EVENTS - 1) |
| 59 | ring->tr_idx = 0; |
| 60 | else |
| 61 | ring->tr_idx++; |
| 62 | } |
| 63 | |
| 64 | static struct tgt_event *tgt_head_event(struct tgt_ring *ring, u32 idx) |
| 65 | { |
| 66 | u32 pidx, off; |
| 67 | |
| 68 | pidx = idx / TGT_EVENT_PER_PAGE; |
| 69 | off = idx % TGT_EVENT_PER_PAGE; |
| 70 | |
| 71 | return (struct tgt_event *) |
| 72 | (ring->tr_pages[pidx] + sizeof(struct tgt_event) * off); |
| 73 | } |
| 74 | |
| 75 | static int tgt_uspace_send_event(u32 type, struct tgt_event *p) |
| 76 | { |
| 77 | struct tgt_event *ev; |
| 78 | struct tgt_ring *ring = &tx_ring; |
| 79 | unsigned long flags; |
| 80 | int err = 0; |
| 81 | |
| 82 | spin_lock_irqsave(&ring->tr_lock, flags); |
| 83 | |
| 84 | ev = tgt_head_event(ring, ring->tr_idx); |
| 85 | if (!ev->hdr.status) |
| 86 | tgt_ring_idx_inc(ring); |
| 87 | else |
| 88 | err = -BUSY; |
| 89 | |
| 90 | spin_unlock_irqrestore(&ring->tr_lock, flags); |
| 91 | |
| 92 | if (err) |
| 93 | return err; |
| 94 | |
| 95 | memcpy(ev, p, sizeof(*ev)); |
| 96 | ev->hdr.type = type; |
| 97 | mb(); |
| 98 | ev->hdr.status = 1; |
| 99 | |
| 100 | flush_dcache_page(virt_to_page(ev)); |
| 101 | |
| 102 | wake_up_interruptible(&tgt_poll_wait); |
| 103 | |
| 104 | return 0; |
| 105 | } |
| 106 | |
FUJITA Tomonori | 2c47f9e | 2007-07-11 15:08:17 +0900 | [diff] [blame] | 107 | int scsi_tgt_uspace_send_cmd(struct scsi_cmnd *cmd, u64 itn_id, |
| 108 | struct scsi_lun *lun, u64 tag) |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 109 | { |
| 110 | struct Scsi_Host *shost = scsi_tgt_cmd_to_host(cmd); |
| 111 | struct tgt_event ev; |
| 112 | int err; |
| 113 | |
| 114 | memset(&ev, 0, sizeof(ev)); |
| 115 | ev.p.cmd_req.host_no = shost->host_no; |
FUJITA Tomonori | 2c47f9e | 2007-07-11 15:08:17 +0900 | [diff] [blame] | 116 | ev.p.cmd_req.itn_id = itn_id; |
FUJITA Tomonori | f10ab66 | 2007-10-25 01:21:30 +0900 | [diff] [blame] | 117 | ev.p.cmd_req.data_len = scsi_bufflen(cmd); |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 118 | memcpy(ev.p.cmd_req.scb, cmd->cmnd, sizeof(ev.p.cmd_req.scb)); |
| 119 | memcpy(ev.p.cmd_req.lun, lun, sizeof(ev.p.cmd_req.lun)); |
| 120 | ev.p.cmd_req.attribute = cmd->tag; |
| 121 | ev.p.cmd_req.tag = tag; |
| 122 | |
| 123 | dprintk("%p %d %u %x %llx\n", cmd, shost->host_no, |
| 124 | ev.p.cmd_req.data_len, cmd->tag, |
| 125 | (unsigned long long) ev.p.cmd_req.tag); |
| 126 | |
| 127 | err = tgt_uspace_send_event(TGT_KEVENT_CMD_REQ, &ev); |
| 128 | if (err) |
| 129 | eprintk("tx buf is full, could not send\n"); |
| 130 | |
| 131 | return err; |
| 132 | } |
| 133 | |
FUJITA Tomonori | 2c47f9e | 2007-07-11 15:08:17 +0900 | [diff] [blame] | 134 | int scsi_tgt_uspace_send_status(struct scsi_cmnd *cmd, u64 itn_id, u64 tag) |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 135 | { |
| 136 | struct Scsi_Host *shost = scsi_tgt_cmd_to_host(cmd); |
| 137 | struct tgt_event ev; |
| 138 | int err; |
| 139 | |
| 140 | memset(&ev, 0, sizeof(ev)); |
| 141 | ev.p.cmd_done.host_no = shost->host_no; |
FUJITA Tomonori | 2c47f9e | 2007-07-11 15:08:17 +0900 | [diff] [blame] | 142 | ev.p.cmd_done.itn_id = itn_id; |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 143 | ev.p.cmd_done.tag = tag; |
| 144 | ev.p.cmd_done.result = cmd->result; |
| 145 | |
| 146 | dprintk("%p %d %llu %u %x\n", cmd, shost->host_no, |
| 147 | (unsigned long long) ev.p.cmd_req.tag, |
| 148 | ev.p.cmd_req.data_len, cmd->tag); |
| 149 | |
| 150 | err = tgt_uspace_send_event(TGT_KEVENT_CMD_DONE, &ev); |
| 151 | if (err) |
| 152 | eprintk("tx buf is full, could not send\n"); |
| 153 | |
| 154 | return err; |
| 155 | } |
| 156 | |
FUJITA Tomonori | 2c47f9e | 2007-07-11 15:08:17 +0900 | [diff] [blame] | 157 | int scsi_tgt_uspace_send_tsk_mgmt(int host_no, u64 itn_id, int function, |
| 158 | u64 tag, struct scsi_lun *scsilun, void *data) |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 159 | { |
| 160 | struct tgt_event ev; |
| 161 | int err; |
| 162 | |
| 163 | memset(&ev, 0, sizeof(ev)); |
| 164 | ev.p.tsk_mgmt_req.host_no = host_no; |
FUJITA Tomonori | 2c47f9e | 2007-07-11 15:08:17 +0900 | [diff] [blame] | 165 | ev.p.tsk_mgmt_req.itn_id = itn_id; |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 166 | ev.p.tsk_mgmt_req.function = function; |
| 167 | ev.p.tsk_mgmt_req.tag = tag; |
| 168 | memcpy(ev.p.tsk_mgmt_req.lun, scsilun, sizeof(ev.p.tsk_mgmt_req.lun)); |
| 169 | ev.p.tsk_mgmt_req.mid = (u64) (unsigned long) data; |
| 170 | |
| 171 | dprintk("%d %x %llx %llx\n", host_no, function, (unsigned long long) tag, |
| 172 | (unsigned long long) ev.p.tsk_mgmt_req.mid); |
| 173 | |
| 174 | err = tgt_uspace_send_event(TGT_KEVENT_TSK_MGMT_REQ, &ev); |
| 175 | if (err) |
| 176 | eprintk("tx buf is full, could not send\n"); |
| 177 | |
| 178 | return err; |
| 179 | } |
| 180 | |
FUJITA Tomonori | 2c47f9e | 2007-07-11 15:08:17 +0900 | [diff] [blame] | 181 | int scsi_tgt_uspace_send_it_nexus_request(int host_no, u64 itn_id, |
| 182 | int function, char *initiator_id) |
| 183 | { |
| 184 | struct tgt_event ev; |
| 185 | int err; |
| 186 | |
| 187 | memset(&ev, 0, sizeof(ev)); |
| 188 | ev.p.it_nexus_req.host_no = host_no; |
| 189 | ev.p.it_nexus_req.function = function; |
| 190 | ev.p.it_nexus_req.itn_id = itn_id; |
| 191 | if (initiator_id) |
| 192 | strncpy(ev.p.it_nexus_req.initiator_id, initiator_id, |
| 193 | sizeof(ev.p.it_nexus_req.initiator_id)); |
| 194 | |
| 195 | dprintk("%d %x %llx\n", host_no, function, (unsigned long long)itn_id); |
| 196 | |
| 197 | err = tgt_uspace_send_event(TGT_KEVENT_IT_NEXUS_REQ, &ev); |
| 198 | if (err) |
| 199 | eprintk("tx buf is full, could not send\n"); |
| 200 | |
| 201 | return err; |
| 202 | } |
| 203 | |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 204 | static int event_recv_msg(struct tgt_event *ev) |
| 205 | { |
| 206 | int err = 0; |
| 207 | |
| 208 | switch (ev->hdr.type) { |
| 209 | case TGT_UEVENT_CMD_RSP: |
| 210 | err = scsi_tgt_kspace_exec(ev->p.cmd_rsp.host_no, |
FUJITA Tomonori | 2c47f9e | 2007-07-11 15:08:17 +0900 | [diff] [blame] | 211 | ev->p.cmd_rsp.itn_id, |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 212 | ev->p.cmd_rsp.result, |
FUJITA Tomonori | bc7e380 | 2007-03-03 09:55:54 +0900 | [diff] [blame] | 213 | ev->p.cmd_rsp.tag, |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 214 | ev->p.cmd_rsp.uaddr, |
FUJITA Tomonori | bc7e380 | 2007-03-03 09:55:54 +0900 | [diff] [blame] | 215 | ev->p.cmd_rsp.len, |
| 216 | ev->p.cmd_rsp.sense_uaddr, |
| 217 | ev->p.cmd_rsp.sense_len, |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 218 | ev->p.cmd_rsp.rw); |
| 219 | break; |
| 220 | case TGT_UEVENT_TSK_MGMT_RSP: |
| 221 | err = scsi_tgt_kspace_tsk_mgmt(ev->p.tsk_mgmt_rsp.host_no, |
FUJITA Tomonori | 2c47f9e | 2007-07-11 15:08:17 +0900 | [diff] [blame] | 222 | ev->p.tsk_mgmt_rsp.itn_id, |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 223 | ev->p.tsk_mgmt_rsp.mid, |
| 224 | ev->p.tsk_mgmt_rsp.result); |
| 225 | break; |
FUJITA Tomonori | 2c47f9e | 2007-07-11 15:08:17 +0900 | [diff] [blame] | 226 | case TGT_UEVENT_IT_NEXUS_RSP: |
| 227 | err = scsi_tgt_kspace_it_nexus_rsp(ev->p.it_nexus_rsp.host_no, |
| 228 | ev->p.it_nexus_rsp.itn_id, |
| 229 | ev->p.it_nexus_rsp.result); |
| 230 | break; |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 231 | default: |
| 232 | eprintk("unknown type %d\n", ev->hdr.type); |
| 233 | err = -EINVAL; |
| 234 | } |
| 235 | |
| 236 | return err; |
| 237 | } |
| 238 | |
| 239 | static ssize_t tgt_write(struct file *file, const char __user * buffer, |
| 240 | size_t count, loff_t * ppos) |
| 241 | { |
| 242 | struct tgt_event *ev; |
| 243 | struct tgt_ring *ring = &rx_ring; |
| 244 | |
| 245 | while (1) { |
| 246 | ev = tgt_head_event(ring, ring->tr_idx); |
| 247 | /* do we need this? */ |
| 248 | flush_dcache_page(virt_to_page(ev)); |
| 249 | |
| 250 | if (!ev->hdr.status) |
| 251 | break; |
| 252 | |
| 253 | tgt_ring_idx_inc(ring); |
| 254 | event_recv_msg(ev); |
| 255 | ev->hdr.status = 0; |
| 256 | }; |
| 257 | |
| 258 | return count; |
| 259 | } |
| 260 | |
| 261 | static unsigned int tgt_poll(struct file * file, struct poll_table_struct *wait) |
| 262 | { |
| 263 | struct tgt_event *ev; |
| 264 | struct tgt_ring *ring = &tx_ring; |
| 265 | unsigned long flags; |
| 266 | unsigned int mask = 0; |
| 267 | u32 idx; |
| 268 | |
| 269 | poll_wait(file, &tgt_poll_wait, wait); |
| 270 | |
| 271 | spin_lock_irqsave(&ring->tr_lock, flags); |
| 272 | |
| 273 | idx = ring->tr_idx ? ring->tr_idx - 1 : TGT_MAX_EVENTS - 1; |
| 274 | ev = tgt_head_event(ring, idx); |
| 275 | if (ev->hdr.status) |
| 276 | mask |= POLLIN | POLLRDNORM; |
| 277 | |
| 278 | spin_unlock_irqrestore(&ring->tr_lock, flags); |
| 279 | |
| 280 | return mask; |
| 281 | } |
| 282 | |
| 283 | static int uspace_ring_map(struct vm_area_struct *vma, unsigned long addr, |
| 284 | struct tgt_ring *ring) |
| 285 | { |
| 286 | int i, err; |
| 287 | |
| 288 | for (i = 0; i < TGT_RING_PAGES; i++) { |
| 289 | struct page *page = virt_to_page(ring->tr_pages[i]); |
| 290 | err = vm_insert_page(vma, addr, page); |
| 291 | if (err) |
| 292 | return err; |
| 293 | addr += PAGE_SIZE; |
| 294 | } |
| 295 | |
| 296 | return 0; |
| 297 | } |
| 298 | |
| 299 | static int tgt_mmap(struct file *filp, struct vm_area_struct *vma) |
| 300 | { |
| 301 | unsigned long addr; |
| 302 | int err; |
| 303 | |
| 304 | if (vma->vm_pgoff) |
| 305 | return -EINVAL; |
| 306 | |
| 307 | if (vma->vm_end - vma->vm_start != TGT_RING_SIZE * 2) { |
| 308 | eprintk("mmap size must be %lu, not %lu \n", |
| 309 | TGT_RING_SIZE * 2, vma->vm_end - vma->vm_start); |
| 310 | return -EINVAL; |
| 311 | } |
| 312 | |
| 313 | addr = vma->vm_start; |
| 314 | err = uspace_ring_map(vma, addr, &tx_ring); |
| 315 | if (err) |
| 316 | return err; |
| 317 | err = uspace_ring_map(vma, addr + TGT_RING_SIZE, &rx_ring); |
| 318 | |
| 319 | return err; |
| 320 | } |
| 321 | |
| 322 | static int tgt_open(struct inode *inode, struct file *file) |
| 323 | { |
| 324 | tx_ring.tr_idx = rx_ring.tr_idx = 0; |
| 325 | |
| 326 | return 0; |
| 327 | } |
| 328 | |
Arjan van de Ven | 00977a5 | 2007-02-12 00:55:34 -0800 | [diff] [blame] | 329 | static const struct file_operations tgt_fops = { |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 330 | .owner = THIS_MODULE, |
| 331 | .open = tgt_open, |
| 332 | .poll = tgt_poll, |
| 333 | .write = tgt_write, |
| 334 | .mmap = tgt_mmap, |
Arnd Bergmann | 6038f37 | 2010-08-15 18:52:59 +0200 | [diff] [blame] | 335 | .llseek = noop_llseek, |
FUJITA Tomonori | 97f7875 | 2006-11-16 19:24:16 +0900 | [diff] [blame] | 336 | }; |
| 337 | |
| 338 | static struct miscdevice tgt_miscdev = { |
| 339 | .minor = MISC_DYNAMIC_MINOR, |
| 340 | .name = "tgt", |
| 341 | .fops = &tgt_fops, |
| 342 | }; |
| 343 | |
| 344 | static void tgt_ring_exit(struct tgt_ring *ring) |
| 345 | { |
| 346 | int i; |
| 347 | |
| 348 | for (i = 0; i < TGT_RING_PAGES; i++) |
| 349 | free_page(ring->tr_pages[i]); |
| 350 | } |
| 351 | |
| 352 | static int tgt_ring_init(struct tgt_ring *ring) |
| 353 | { |
| 354 | int i; |
| 355 | |
| 356 | spin_lock_init(&ring->tr_lock); |
| 357 | |
| 358 | for (i = 0; i < TGT_RING_PAGES; i++) { |
| 359 | ring->tr_pages[i] = get_zeroed_page(GFP_KERNEL); |
| 360 | if (!ring->tr_pages[i]) { |
| 361 | eprintk("out of memory\n"); |
| 362 | return -ENOMEM; |
| 363 | } |
| 364 | } |
| 365 | |
| 366 | return 0; |
| 367 | } |
| 368 | |
| 369 | void scsi_tgt_if_exit(void) |
| 370 | { |
| 371 | tgt_ring_exit(&tx_ring); |
| 372 | tgt_ring_exit(&rx_ring); |
| 373 | misc_deregister(&tgt_miscdev); |
| 374 | } |
| 375 | |
| 376 | int scsi_tgt_if_init(void) |
| 377 | { |
| 378 | int err; |
| 379 | |
| 380 | err = tgt_ring_init(&tx_ring); |
| 381 | if (err) |
| 382 | return err; |
| 383 | |
| 384 | err = tgt_ring_init(&rx_ring); |
| 385 | if (err) |
| 386 | goto free_tx_ring; |
| 387 | |
| 388 | err = misc_register(&tgt_miscdev); |
| 389 | if (err) |
| 390 | goto free_rx_ring; |
| 391 | |
| 392 | return 0; |
| 393 | free_rx_ring: |
| 394 | tgt_ring_exit(&rx_ring); |
| 395 | free_tx_ring: |
| 396 | tgt_ring_exit(&tx_ring); |
| 397 | |
| 398 | return err; |
| 399 | } |