]>
Commit | Line | Data |
---|---|---|
97f78759 FT |
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> | |
5a0e3ad6 | 23 | #include <linux/gfp.h> |
97f78759 | 24 | #include <linux/file.h> |
556e4b0b | 25 | #include <linux/smp_lock.h> |
97f78759 FT |
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 | ||
e42ebefe | 34 | #include <asm/cacheflush.h> |
35 | ||
97f78759 FT |
36 | #include "scsi_tgt_priv.h" |
37 | ||
930e99bd FT |
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 | ||
97f78759 FT |
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 | ||
2c47f9ef FT |
107 | int scsi_tgt_uspace_send_cmd(struct scsi_cmnd *cmd, u64 itn_id, |
108 | struct scsi_lun *lun, u64 tag) | |
97f78759 FT |
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; | |
2c47f9ef | 116 | ev.p.cmd_req.itn_id = itn_id; |
f10ab66f | 117 | ev.p.cmd_req.data_len = scsi_bufflen(cmd); |
97f78759 FT |
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 | ||
2c47f9ef | 134 | int scsi_tgt_uspace_send_status(struct scsi_cmnd *cmd, u64 itn_id, u64 tag) |
97f78759 FT |
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; | |
2c47f9ef | 142 | ev.p.cmd_done.itn_id = itn_id; |
97f78759 FT |
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 | ||
2c47f9ef FT |
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) | |
97f78759 FT |
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; | |
2c47f9ef | 165 | ev.p.tsk_mgmt_req.itn_id = itn_id; |
97f78759 FT |
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 | ||
2c47f9ef FT |
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 | ||
97f78759 FT |
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, | |
2c47f9ef | 211 | ev->p.cmd_rsp.itn_id, |
97f78759 | 212 | ev->p.cmd_rsp.result, |
bc7e380a | 213 | ev->p.cmd_rsp.tag, |
97f78759 | 214 | ev->p.cmd_rsp.uaddr, |
bc7e380a FT |
215 | ev->p.cmd_rsp.len, |
216 | ev->p.cmd_rsp.sense_uaddr, | |
217 | ev->p.cmd_rsp.sense_len, | |
97f78759 FT |
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, | |
2c47f9ef | 222 | ev->p.tsk_mgmt_rsp.itn_id, |
97f78759 FT |
223 | ev->p.tsk_mgmt_rsp.mid, |
224 | ev->p.tsk_mgmt_rsp.result); | |
225 | break; | |
2c47f9ef FT |
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; | |
97f78759 FT |
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 | ||
556e4b0b | 326 | cycle_kernel_lock(); |
97f78759 FT |
327 | return 0; |
328 | } | |
329 | ||
00977a59 | 330 | static const struct file_operations tgt_fops = { |
97f78759 FT |
331 | .owner = THIS_MODULE, |
332 | .open = tgt_open, | |
333 | .poll = tgt_poll, | |
334 | .write = tgt_write, | |
335 | .mmap = tgt_mmap, | |
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 | } |