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block: split scsi_request out of struct request
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1 /*
2 * History:
3 * Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
4 * to allow user process control of SCSI devices.
5 * Development Sponsored by Killy Corp. NY NY
6 *
7 * Original driver (sg.c):
8 * Copyright (C) 1992 Lawrence Foard
9 * Version 2 and 3 extensions to driver:
10 * Copyright (C) 1998 - 2014 Douglas Gilbert
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2, or (at your option)
15 * any later version.
16 *
17 */
18
19 static int sg_version_num = 30536; /* 2 digits for each component */
20 #define SG_VERSION_STR "3.5.36"
21
22 /*
23 * D. P. Gilbert (dgilbert@interlog.com), notes:
24 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
25 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING
26 * (otherwise the macros compile to empty statements).
27 *
28 */
29 #include <linux/module.h>
30
31 #include <linux/fs.h>
32 #include <linux/kernel.h>
33 #include <linux/sched.h>
34 #include <linux/string.h>
35 #include <linux/mm.h>
36 #include <linux/errno.h>
37 #include <linux/mtio.h>
38 #include <linux/ioctl.h>
39 #include <linux/slab.h>
40 #include <linux/fcntl.h>
41 #include <linux/init.h>
42 #include <linux/poll.h>
43 #include <linux/moduleparam.h>
44 #include <linux/cdev.h>
45 #include <linux/idr.h>
46 #include <linux/seq_file.h>
47 #include <linux/blkdev.h>
48 #include <linux/delay.h>
49 #include <linux/blktrace_api.h>
50 #include <linux/mutex.h>
51 #include <linux/atomic.h>
52 #include <linux/ratelimit.h>
53 #include <linux/uio.h>
54
55 #include "scsi.h"
56 #include <scsi/scsi_dbg.h>
57 #include <scsi/scsi_host.h>
58 #include <scsi/scsi_driver.h>
59 #include <scsi/scsi_ioctl.h>
60 #include <scsi/sg.h>
61
62 #include "scsi_logging.h"
63
64 #ifdef CONFIG_SCSI_PROC_FS
65 #include <linux/proc_fs.h>
66 static char *sg_version_date = "20140603";
67
68 static int sg_proc_init(void);
69 static void sg_proc_cleanup(void);
70 #endif
71
72 #define SG_ALLOW_DIO_DEF 0
73
74 #define SG_MAX_DEVS 32768
75
76 /* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type
77 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater
78 * than 16 bytes are "variable length" whose length is a multiple of 4
79 */
80 #define SG_MAX_CDB_SIZE 252
81
82 #define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
83
84 int sg_big_buff = SG_DEF_RESERVED_SIZE;
85 /* N.B. This variable is readable and writeable via
86 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
87 of this size (or less if there is not enough memory) will be reserved
88 for use by this file descriptor. [Deprecated usage: this variable is also
89 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
90 the kernel (i.e. it is not a module).] */
91 static int def_reserved_size = -1; /* picks up init parameter */
92 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
93
94 static int scatter_elem_sz = SG_SCATTER_SZ;
95 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
96
97 #define SG_SECTOR_SZ 512
98
99 static int sg_add_device(struct device *, struct class_interface *);
100 static void sg_remove_device(struct device *, struct class_interface *);
101
102 static DEFINE_IDR(sg_index_idr);
103 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
104 file descriptor list for device */
105
106 static struct class_interface sg_interface = {
107 .add_dev = sg_add_device,
108 .remove_dev = sg_remove_device,
109 };
110
111 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
112 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
113 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
114 unsigned bufflen; /* Size of (aggregate) data buffer */
115 struct page **pages;
116 int page_order;
117 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
118 unsigned char cmd_opcode; /* first byte of command */
119 } Sg_scatter_hold;
120
121 struct sg_device; /* forward declarations */
122 struct sg_fd;
123
124 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
125 struct sg_request *nextrp; /* NULL -> tail request (slist) */
126 struct sg_fd *parentfp; /* NULL -> not in use */
127 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
128 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
129 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
130 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
131 char orphan; /* 1 -> drop on sight, 0 -> normal */
132 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
133 /* done protected by rq_list_lock */
134 char done; /* 0->before bh, 1->before read, 2->read */
135 struct request *rq;
136 struct bio *bio;
137 struct execute_work ew;
138 } Sg_request;
139
140 typedef struct sg_fd { /* holds the state of a file descriptor */
141 struct list_head sfd_siblings; /* protected by device's sfd_lock */
142 struct sg_device *parentdp; /* owning device */
143 wait_queue_head_t read_wait; /* queue read until command done */
144 rwlock_t rq_list_lock; /* protect access to list in req_arr */
145 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
146 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
147 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
148 unsigned save_scat_len; /* original length of trunc. scat. element */
149 Sg_request *headrp; /* head of request slist, NULL->empty */
150 struct fasync_struct *async_qp; /* used by asynchronous notification */
151 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
152 char low_dma; /* as in parent but possibly overridden to 1 */
153 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
154 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
155 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
156 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
157 char mmap_called; /* 0 -> mmap() never called on this fd */
158 struct kref f_ref;
159 struct execute_work ew;
160 } Sg_fd;
161
162 typedef struct sg_device { /* holds the state of each scsi generic device */
163 struct scsi_device *device;
164 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */
165 struct mutex open_rel_lock; /* held when in open() or release() */
166 int sg_tablesize; /* adapter's max scatter-gather table size */
167 u32 index; /* device index number */
168 struct list_head sfds;
169 rwlock_t sfd_lock; /* protect access to sfd list */
170 atomic_t detaching; /* 0->device usable, 1->device detaching */
171 bool exclude; /* 1->open(O_EXCL) succeeded and is active */
172 int open_cnt; /* count of opens (perhaps < num(sfds) ) */
173 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
174 struct gendisk *disk;
175 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
176 struct kref d_ref;
177 } Sg_device;
178
179 /* tasklet or soft irq callback */
180 static void sg_rq_end_io(struct request *rq, int uptodate);
181 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
182 static int sg_finish_rem_req(Sg_request * srp);
183 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
184 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
185 Sg_request * srp);
186 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
187 const char __user *buf, size_t count, int blocking,
188 int read_only, int sg_io_owned, Sg_request **o_srp);
189 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
190 unsigned char *cmnd, int timeout, int blocking);
191 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
192 static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
193 static void sg_build_reserve(Sg_fd * sfp, int req_size);
194 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
195 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
196 static Sg_fd *sg_add_sfp(Sg_device * sdp);
197 static void sg_remove_sfp(struct kref *);
198 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
199 static Sg_request *sg_add_request(Sg_fd * sfp);
200 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
201 static int sg_res_in_use(Sg_fd * sfp);
202 static Sg_device *sg_get_dev(int dev);
203 static void sg_device_destroy(struct kref *kref);
204
205 #define SZ_SG_HEADER sizeof(struct sg_header)
206 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
207 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
208 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
209
210 #define sg_printk(prefix, sdp, fmt, a...) \
211 sdev_prefix_printk(prefix, (sdp)->device, \
212 (sdp)->disk->disk_name, fmt, ##a)
213
214 static int sg_allow_access(struct file *filp, unsigned char *cmd)
215 {
216 struct sg_fd *sfp = filp->private_data;
217
218 if (sfp->parentdp->device->type == TYPE_SCANNER)
219 return 0;
220
221 return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
222 }
223
224 static int
225 open_wait(Sg_device *sdp, int flags)
226 {
227 int retval = 0;
228
229 if (flags & O_EXCL) {
230 while (sdp->open_cnt > 0) {
231 mutex_unlock(&sdp->open_rel_lock);
232 retval = wait_event_interruptible(sdp->open_wait,
233 (atomic_read(&sdp->detaching) ||
234 !sdp->open_cnt));
235 mutex_lock(&sdp->open_rel_lock);
236
237 if (retval) /* -ERESTARTSYS */
238 return retval;
239 if (atomic_read(&sdp->detaching))
240 return -ENODEV;
241 }
242 } else {
243 while (sdp->exclude) {
244 mutex_unlock(&sdp->open_rel_lock);
245 retval = wait_event_interruptible(sdp->open_wait,
246 (atomic_read(&sdp->detaching) ||
247 !sdp->exclude));
248 mutex_lock(&sdp->open_rel_lock);
249
250 if (retval) /* -ERESTARTSYS */
251 return retval;
252 if (atomic_read(&sdp->detaching))
253 return -ENODEV;
254 }
255 }
256
257 return retval;
258 }
259
260 /* Returns 0 on success, else a negated errno value */
261 static int
262 sg_open(struct inode *inode, struct file *filp)
263 {
264 int dev = iminor(inode);
265 int flags = filp->f_flags;
266 struct request_queue *q;
267 Sg_device *sdp;
268 Sg_fd *sfp;
269 int retval;
270
271 nonseekable_open(inode, filp);
272 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
273 return -EPERM; /* Can't lock it with read only access */
274 sdp = sg_get_dev(dev);
275 if (IS_ERR(sdp))
276 return PTR_ERR(sdp);
277
278 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
279 "sg_open: flags=0x%x\n", flags));
280
281 /* This driver's module count bumped by fops_get in <linux/fs.h> */
282 /* Prevent the device driver from vanishing while we sleep */
283 retval = scsi_device_get(sdp->device);
284 if (retval)
285 goto sg_put;
286
287 retval = scsi_autopm_get_device(sdp->device);
288 if (retval)
289 goto sdp_put;
290
291 /* scsi_block_when_processing_errors() may block so bypass
292 * check if O_NONBLOCK. Permits SCSI commands to be issued
293 * during error recovery. Tread carefully. */
294 if (!((flags & O_NONBLOCK) ||
295 scsi_block_when_processing_errors(sdp->device))) {
296 retval = -ENXIO;
297 /* we are in error recovery for this device */
298 goto error_out;
299 }
300
301 mutex_lock(&sdp->open_rel_lock);
302 if (flags & O_NONBLOCK) {
303 if (flags & O_EXCL) {
304 if (sdp->open_cnt > 0) {
305 retval = -EBUSY;
306 goto error_mutex_locked;
307 }
308 } else {
309 if (sdp->exclude) {
310 retval = -EBUSY;
311 goto error_mutex_locked;
312 }
313 }
314 } else {
315 retval = open_wait(sdp, flags);
316 if (retval) /* -ERESTARTSYS or -ENODEV */
317 goto error_mutex_locked;
318 }
319
320 /* N.B. at this point we are holding the open_rel_lock */
321 if (flags & O_EXCL)
322 sdp->exclude = true;
323
324 if (sdp->open_cnt < 1) { /* no existing opens */
325 sdp->sgdebug = 0;
326 q = sdp->device->request_queue;
327 sdp->sg_tablesize = queue_max_segments(q);
328 }
329 sfp = sg_add_sfp(sdp);
330 if (IS_ERR(sfp)) {
331 retval = PTR_ERR(sfp);
332 goto out_undo;
333 }
334
335 filp->private_data = sfp;
336 sdp->open_cnt++;
337 mutex_unlock(&sdp->open_rel_lock);
338
339 retval = 0;
340 sg_put:
341 kref_put(&sdp->d_ref, sg_device_destroy);
342 return retval;
343
344 out_undo:
345 if (flags & O_EXCL) {
346 sdp->exclude = false; /* undo if error */
347 wake_up_interruptible(&sdp->open_wait);
348 }
349 error_mutex_locked:
350 mutex_unlock(&sdp->open_rel_lock);
351 error_out:
352 scsi_autopm_put_device(sdp->device);
353 sdp_put:
354 scsi_device_put(sdp->device);
355 goto sg_put;
356 }
357
358 /* Release resources associated with a successful sg_open()
359 * Returns 0 on success, else a negated errno value */
360 static int
361 sg_release(struct inode *inode, struct file *filp)
362 {
363 Sg_device *sdp;
364 Sg_fd *sfp;
365
366 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
367 return -ENXIO;
368 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
369
370 mutex_lock(&sdp->open_rel_lock);
371 scsi_autopm_put_device(sdp->device);
372 kref_put(&sfp->f_ref, sg_remove_sfp);
373 sdp->open_cnt--;
374
375 /* possibly many open()s waiting on exlude clearing, start many;
376 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
377 if (sdp->exclude) {
378 sdp->exclude = false;
379 wake_up_interruptible_all(&sdp->open_wait);
380 } else if (0 == sdp->open_cnt) {
381 wake_up_interruptible(&sdp->open_wait);
382 }
383 mutex_unlock(&sdp->open_rel_lock);
384 return 0;
385 }
386
387 static ssize_t
388 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
389 {
390 Sg_device *sdp;
391 Sg_fd *sfp;
392 Sg_request *srp;
393 int req_pack_id = -1;
394 sg_io_hdr_t *hp;
395 struct sg_header *old_hdr = NULL;
396 int retval = 0;
397
398 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
399 return -ENXIO;
400 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
401 "sg_read: count=%d\n", (int) count));
402
403 if (!access_ok(VERIFY_WRITE, buf, count))
404 return -EFAULT;
405 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
406 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
407 if (!old_hdr)
408 return -ENOMEM;
409 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
410 retval = -EFAULT;
411 goto free_old_hdr;
412 }
413 if (old_hdr->reply_len < 0) {
414 if (count >= SZ_SG_IO_HDR) {
415 sg_io_hdr_t *new_hdr;
416 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
417 if (!new_hdr) {
418 retval = -ENOMEM;
419 goto free_old_hdr;
420 }
421 retval =__copy_from_user
422 (new_hdr, buf, SZ_SG_IO_HDR);
423 req_pack_id = new_hdr->pack_id;
424 kfree(new_hdr);
425 if (retval) {
426 retval = -EFAULT;
427 goto free_old_hdr;
428 }
429 }
430 } else
431 req_pack_id = old_hdr->pack_id;
432 }
433 srp = sg_get_rq_mark(sfp, req_pack_id);
434 if (!srp) { /* now wait on packet to arrive */
435 if (atomic_read(&sdp->detaching)) {
436 retval = -ENODEV;
437 goto free_old_hdr;
438 }
439 if (filp->f_flags & O_NONBLOCK) {
440 retval = -EAGAIN;
441 goto free_old_hdr;
442 }
443 retval = wait_event_interruptible(sfp->read_wait,
444 (atomic_read(&sdp->detaching) ||
445 (srp = sg_get_rq_mark(sfp, req_pack_id))));
446 if (atomic_read(&sdp->detaching)) {
447 retval = -ENODEV;
448 goto free_old_hdr;
449 }
450 if (retval) {
451 /* -ERESTARTSYS as signal hit process */
452 goto free_old_hdr;
453 }
454 }
455 if (srp->header.interface_id != '\0') {
456 retval = sg_new_read(sfp, buf, count, srp);
457 goto free_old_hdr;
458 }
459
460 hp = &srp->header;
461 if (old_hdr == NULL) {
462 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
463 if (! old_hdr) {
464 retval = -ENOMEM;
465 goto free_old_hdr;
466 }
467 }
468 memset(old_hdr, 0, SZ_SG_HEADER);
469 old_hdr->reply_len = (int) hp->timeout;
470 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
471 old_hdr->pack_id = hp->pack_id;
472 old_hdr->twelve_byte =
473 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
474 old_hdr->target_status = hp->masked_status;
475 old_hdr->host_status = hp->host_status;
476 old_hdr->driver_status = hp->driver_status;
477 if ((CHECK_CONDITION & hp->masked_status) ||
478 (DRIVER_SENSE & hp->driver_status))
479 memcpy(old_hdr->sense_buffer, srp->sense_b,
480 sizeof (old_hdr->sense_buffer));
481 switch (hp->host_status) {
482 /* This setup of 'result' is for backward compatibility and is best
483 ignored by the user who should use target, host + driver status */
484 case DID_OK:
485 case DID_PASSTHROUGH:
486 case DID_SOFT_ERROR:
487 old_hdr->result = 0;
488 break;
489 case DID_NO_CONNECT:
490 case DID_BUS_BUSY:
491 case DID_TIME_OUT:
492 old_hdr->result = EBUSY;
493 break;
494 case DID_BAD_TARGET:
495 case DID_ABORT:
496 case DID_PARITY:
497 case DID_RESET:
498 case DID_BAD_INTR:
499 old_hdr->result = EIO;
500 break;
501 case DID_ERROR:
502 old_hdr->result = (srp->sense_b[0] == 0 &&
503 hp->masked_status == GOOD) ? 0 : EIO;
504 break;
505 default:
506 old_hdr->result = EIO;
507 break;
508 }
509
510 /* Now copy the result back to the user buffer. */
511 if (count >= SZ_SG_HEADER) {
512 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
513 retval = -EFAULT;
514 goto free_old_hdr;
515 }
516 buf += SZ_SG_HEADER;
517 if (count > old_hdr->reply_len)
518 count = old_hdr->reply_len;
519 if (count > SZ_SG_HEADER) {
520 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
521 retval = -EFAULT;
522 goto free_old_hdr;
523 }
524 }
525 } else
526 count = (old_hdr->result == 0) ? 0 : -EIO;
527 sg_finish_rem_req(srp);
528 retval = count;
529 free_old_hdr:
530 kfree(old_hdr);
531 return retval;
532 }
533
534 static ssize_t
535 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
536 {
537 sg_io_hdr_t *hp = &srp->header;
538 int err = 0, err2;
539 int len;
540
541 if (count < SZ_SG_IO_HDR) {
542 err = -EINVAL;
543 goto err_out;
544 }
545 hp->sb_len_wr = 0;
546 if ((hp->mx_sb_len > 0) && hp->sbp) {
547 if ((CHECK_CONDITION & hp->masked_status) ||
548 (DRIVER_SENSE & hp->driver_status)) {
549 int sb_len = SCSI_SENSE_BUFFERSIZE;
550 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
551 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
552 len = (len > sb_len) ? sb_len : len;
553 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
554 err = -EFAULT;
555 goto err_out;
556 }
557 hp->sb_len_wr = len;
558 }
559 }
560 if (hp->masked_status || hp->host_status || hp->driver_status)
561 hp->info |= SG_INFO_CHECK;
562 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
563 err = -EFAULT;
564 goto err_out;
565 }
566 err_out:
567 err2 = sg_finish_rem_req(srp);
568 return err ? : err2 ? : count;
569 }
570
571 static ssize_t
572 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
573 {
574 int mxsize, cmd_size, k;
575 int input_size, blocking;
576 unsigned char opcode;
577 Sg_device *sdp;
578 Sg_fd *sfp;
579 Sg_request *srp;
580 struct sg_header old_hdr;
581 sg_io_hdr_t *hp;
582 unsigned char cmnd[SG_MAX_CDB_SIZE];
583
584 if (unlikely(segment_eq(get_fs(), KERNEL_DS)))
585 return -EINVAL;
586
587 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
588 return -ENXIO;
589 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
590 "sg_write: count=%d\n", (int) count));
591 if (atomic_read(&sdp->detaching))
592 return -ENODEV;
593 if (!((filp->f_flags & O_NONBLOCK) ||
594 scsi_block_when_processing_errors(sdp->device)))
595 return -ENXIO;
596
597 if (!access_ok(VERIFY_READ, buf, count))
598 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
599 if (count < SZ_SG_HEADER)
600 return -EIO;
601 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
602 return -EFAULT;
603 blocking = !(filp->f_flags & O_NONBLOCK);
604 if (old_hdr.reply_len < 0)
605 return sg_new_write(sfp, filp, buf, count,
606 blocking, 0, 0, NULL);
607 if (count < (SZ_SG_HEADER + 6))
608 return -EIO; /* The minimum scsi command length is 6 bytes. */
609
610 if (!(srp = sg_add_request(sfp))) {
611 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
612 "sg_write: queue full\n"));
613 return -EDOM;
614 }
615 buf += SZ_SG_HEADER;
616 __get_user(opcode, buf);
617 if (sfp->next_cmd_len > 0) {
618 cmd_size = sfp->next_cmd_len;
619 sfp->next_cmd_len = 0; /* reset so only this write() effected */
620 } else {
621 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
622 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
623 cmd_size = 12;
624 }
625 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
626 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
627 /* Determine buffer size. */
628 input_size = count - cmd_size;
629 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
630 mxsize -= SZ_SG_HEADER;
631 input_size -= SZ_SG_HEADER;
632 if (input_size < 0) {
633 sg_remove_request(sfp, srp);
634 return -EIO; /* User did not pass enough bytes for this command. */
635 }
636 hp = &srp->header;
637 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
638 hp->cmd_len = (unsigned char) cmd_size;
639 hp->iovec_count = 0;
640 hp->mx_sb_len = 0;
641 if (input_size > 0)
642 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
643 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
644 else
645 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
646 hp->dxfer_len = mxsize;
647 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
648 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
649 hp->dxferp = (char __user *)buf + cmd_size;
650 else
651 hp->dxferp = NULL;
652 hp->sbp = NULL;
653 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
654 hp->flags = input_size; /* structure abuse ... */
655 hp->pack_id = old_hdr.pack_id;
656 hp->usr_ptr = NULL;
657 if (__copy_from_user(cmnd, buf, cmd_size))
658 return -EFAULT;
659 /*
660 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
661 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
662 * is a non-zero input_size, so emit a warning.
663 */
664 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
665 static char cmd[TASK_COMM_LEN];
666 if (strcmp(current->comm, cmd)) {
667 printk_ratelimited(KERN_WARNING
668 "sg_write: data in/out %d/%d bytes "
669 "for SCSI command 0x%x-- guessing "
670 "data in;\n program %s not setting "
671 "count and/or reply_len properly\n",
672 old_hdr.reply_len - (int)SZ_SG_HEADER,
673 input_size, (unsigned int) cmnd[0],
674 current->comm);
675 strcpy(cmd, current->comm);
676 }
677 }
678 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
679 return (k < 0) ? k : count;
680 }
681
682 static ssize_t
683 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
684 size_t count, int blocking, int read_only, int sg_io_owned,
685 Sg_request **o_srp)
686 {
687 int k;
688 Sg_request *srp;
689 sg_io_hdr_t *hp;
690 unsigned char cmnd[SG_MAX_CDB_SIZE];
691 int timeout;
692 unsigned long ul_timeout;
693
694 if (count < SZ_SG_IO_HDR)
695 return -EINVAL;
696 if (!access_ok(VERIFY_READ, buf, count))
697 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
698
699 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
700 if (!(srp = sg_add_request(sfp))) {
701 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
702 "sg_new_write: queue full\n"));
703 return -EDOM;
704 }
705 srp->sg_io_owned = sg_io_owned;
706 hp = &srp->header;
707 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
708 sg_remove_request(sfp, srp);
709 return -EFAULT;
710 }
711 if (hp->interface_id != 'S') {
712 sg_remove_request(sfp, srp);
713 return -ENOSYS;
714 }
715 if (hp->flags & SG_FLAG_MMAP_IO) {
716 if (hp->dxfer_len > sfp->reserve.bufflen) {
717 sg_remove_request(sfp, srp);
718 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
719 }
720 if (hp->flags & SG_FLAG_DIRECT_IO) {
721 sg_remove_request(sfp, srp);
722 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
723 }
724 if (sg_res_in_use(sfp)) {
725 sg_remove_request(sfp, srp);
726 return -EBUSY; /* reserve buffer already being used */
727 }
728 }
729 ul_timeout = msecs_to_jiffies(srp->header.timeout);
730 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
731 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
732 sg_remove_request(sfp, srp);
733 return -EMSGSIZE;
734 }
735 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
736 sg_remove_request(sfp, srp);
737 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
738 }
739 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
740 sg_remove_request(sfp, srp);
741 return -EFAULT;
742 }
743 if (read_only && sg_allow_access(file, cmnd)) {
744 sg_remove_request(sfp, srp);
745 return -EPERM;
746 }
747 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
748 if (k < 0)
749 return k;
750 if (o_srp)
751 *o_srp = srp;
752 return count;
753 }
754
755 static int
756 sg_common_write(Sg_fd * sfp, Sg_request * srp,
757 unsigned char *cmnd, int timeout, int blocking)
758 {
759 int k, at_head;
760 Sg_device *sdp = sfp->parentdp;
761 sg_io_hdr_t *hp = &srp->header;
762
763 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
764 hp->status = 0;
765 hp->masked_status = 0;
766 hp->msg_status = 0;
767 hp->info = 0;
768 hp->host_status = 0;
769 hp->driver_status = 0;
770 hp->resid = 0;
771 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
772 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
773 (int) cmnd[0], (int) hp->cmd_len));
774
775 k = sg_start_req(srp, cmnd);
776 if (k) {
777 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
778 "sg_common_write: start_req err=%d\n", k));
779 sg_finish_rem_req(srp);
780 return k; /* probably out of space --> ENOMEM */
781 }
782 if (atomic_read(&sdp->detaching)) {
783 if (srp->bio) {
784 scsi_req_free_cmd(scsi_req(srp->rq));
785 blk_end_request_all(srp->rq, -EIO);
786 srp->rq = NULL;
787 }
788
789 sg_finish_rem_req(srp);
790 return -ENODEV;
791 }
792
793 hp->duration = jiffies_to_msecs(jiffies);
794 if (hp->interface_id != '\0' && /* v3 (or later) interface */
795 (SG_FLAG_Q_AT_TAIL & hp->flags))
796 at_head = 0;
797 else
798 at_head = 1;
799
800 srp->rq->timeout = timeout;
801 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
802 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
803 srp->rq, at_head, sg_rq_end_io);
804 return 0;
805 }
806
807 static int srp_done(Sg_fd *sfp, Sg_request *srp)
808 {
809 unsigned long flags;
810 int ret;
811
812 read_lock_irqsave(&sfp->rq_list_lock, flags);
813 ret = srp->done;
814 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
815 return ret;
816 }
817
818 static int max_sectors_bytes(struct request_queue *q)
819 {
820 unsigned int max_sectors = queue_max_sectors(q);
821
822 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
823
824 return max_sectors << 9;
825 }
826
827 static long
828 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
829 {
830 void __user *p = (void __user *)arg;
831 int __user *ip = p;
832 int result, val, read_only;
833 Sg_device *sdp;
834 Sg_fd *sfp;
835 Sg_request *srp;
836 unsigned long iflags;
837
838 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
839 return -ENXIO;
840
841 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
842 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
843 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
844
845 switch (cmd_in) {
846 case SG_IO:
847 if (atomic_read(&sdp->detaching))
848 return -ENODEV;
849 if (!scsi_block_when_processing_errors(sdp->device))
850 return -ENXIO;
851 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
852 return -EFAULT;
853 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
854 1, read_only, 1, &srp);
855 if (result < 0)
856 return result;
857 result = wait_event_interruptible(sfp->read_wait,
858 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
859 if (atomic_read(&sdp->detaching))
860 return -ENODEV;
861 write_lock_irq(&sfp->rq_list_lock);
862 if (srp->done) {
863 srp->done = 2;
864 write_unlock_irq(&sfp->rq_list_lock);
865 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
866 return (result < 0) ? result : 0;
867 }
868 srp->orphan = 1;
869 write_unlock_irq(&sfp->rq_list_lock);
870 return result; /* -ERESTARTSYS because signal hit process */
871 case SG_SET_TIMEOUT:
872 result = get_user(val, ip);
873 if (result)
874 return result;
875 if (val < 0)
876 return -EIO;
877 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
878 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
879 INT_MAX);
880 sfp->timeout_user = val;
881 sfp->timeout = mult_frac(val, HZ, USER_HZ);
882
883 return 0;
884 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
885 /* strange ..., for backward compatibility */
886 return sfp->timeout_user;
887 case SG_SET_FORCE_LOW_DMA:
888 result = get_user(val, ip);
889 if (result)
890 return result;
891 if (val) {
892 sfp->low_dma = 1;
893 if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
894 val = (int) sfp->reserve.bufflen;
895 sg_remove_scat(sfp, &sfp->reserve);
896 sg_build_reserve(sfp, val);
897 }
898 } else {
899 if (atomic_read(&sdp->detaching))
900 return -ENODEV;
901 sfp->low_dma = sdp->device->host->unchecked_isa_dma;
902 }
903 return 0;
904 case SG_GET_LOW_DMA:
905 return put_user((int) sfp->low_dma, ip);
906 case SG_GET_SCSI_ID:
907 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
908 return -EFAULT;
909 else {
910 sg_scsi_id_t __user *sg_idp = p;
911
912 if (atomic_read(&sdp->detaching))
913 return -ENODEV;
914 __put_user((int) sdp->device->host->host_no,
915 &sg_idp->host_no);
916 __put_user((int) sdp->device->channel,
917 &sg_idp->channel);
918 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
919 __put_user((int) sdp->device->lun, &sg_idp->lun);
920 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
921 __put_user((short) sdp->device->host->cmd_per_lun,
922 &sg_idp->h_cmd_per_lun);
923 __put_user((short) sdp->device->queue_depth,
924 &sg_idp->d_queue_depth);
925 __put_user(0, &sg_idp->unused[0]);
926 __put_user(0, &sg_idp->unused[1]);
927 return 0;
928 }
929 case SG_SET_FORCE_PACK_ID:
930 result = get_user(val, ip);
931 if (result)
932 return result;
933 sfp->force_packid = val ? 1 : 0;
934 return 0;
935 case SG_GET_PACK_ID:
936 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
937 return -EFAULT;
938 read_lock_irqsave(&sfp->rq_list_lock, iflags);
939 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
940 if ((1 == srp->done) && (!srp->sg_io_owned)) {
941 read_unlock_irqrestore(&sfp->rq_list_lock,
942 iflags);
943 __put_user(srp->header.pack_id, ip);
944 return 0;
945 }
946 }
947 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
948 __put_user(-1, ip);
949 return 0;
950 case SG_GET_NUM_WAITING:
951 read_lock_irqsave(&sfp->rq_list_lock, iflags);
952 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
953 if ((1 == srp->done) && (!srp->sg_io_owned))
954 ++val;
955 }
956 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
957 return put_user(val, ip);
958 case SG_GET_SG_TABLESIZE:
959 return put_user(sdp->sg_tablesize, ip);
960 case SG_SET_RESERVED_SIZE:
961 result = get_user(val, ip);
962 if (result)
963 return result;
964 if (val < 0)
965 return -EINVAL;
966 val = min_t(int, val,
967 max_sectors_bytes(sdp->device->request_queue));
968 if (val != sfp->reserve.bufflen) {
969 if (sg_res_in_use(sfp) || sfp->mmap_called)
970 return -EBUSY;
971 sg_remove_scat(sfp, &sfp->reserve);
972 sg_build_reserve(sfp, val);
973 }
974 return 0;
975 case SG_GET_RESERVED_SIZE:
976 val = min_t(int, sfp->reserve.bufflen,
977 max_sectors_bytes(sdp->device->request_queue));
978 return put_user(val, ip);
979 case SG_SET_COMMAND_Q:
980 result = get_user(val, ip);
981 if (result)
982 return result;
983 sfp->cmd_q = val ? 1 : 0;
984 return 0;
985 case SG_GET_COMMAND_Q:
986 return put_user((int) sfp->cmd_q, ip);
987 case SG_SET_KEEP_ORPHAN:
988 result = get_user(val, ip);
989 if (result)
990 return result;
991 sfp->keep_orphan = val;
992 return 0;
993 case SG_GET_KEEP_ORPHAN:
994 return put_user((int) sfp->keep_orphan, ip);
995 case SG_NEXT_CMD_LEN:
996 result = get_user(val, ip);
997 if (result)
998 return result;
999 sfp->next_cmd_len = (val > 0) ? val : 0;
1000 return 0;
1001 case SG_GET_VERSION_NUM:
1002 return put_user(sg_version_num, ip);
1003 case SG_GET_ACCESS_COUNT:
1004 /* faked - we don't have a real access count anymore */
1005 val = (sdp->device ? 1 : 0);
1006 return put_user(val, ip);
1007 case SG_GET_REQUEST_TABLE:
1008 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
1009 return -EFAULT;
1010 else {
1011 sg_req_info_t *rinfo;
1012 unsigned int ms;
1013
1014 rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
1015 GFP_KERNEL);
1016 if (!rinfo)
1017 return -ENOMEM;
1018 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1019 for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
1020 ++val, srp = srp ? srp->nextrp : srp) {
1021 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
1022 if (srp) {
1023 rinfo[val].req_state = srp->done + 1;
1024 rinfo[val].problem =
1025 srp->header.masked_status &
1026 srp->header.host_status &
1027 srp->header.driver_status;
1028 if (srp->done)
1029 rinfo[val].duration =
1030 srp->header.duration;
1031 else {
1032 ms = jiffies_to_msecs(jiffies);
1033 rinfo[val].duration =
1034 (ms > srp->header.duration) ?
1035 (ms - srp->header.duration) : 0;
1036 }
1037 rinfo[val].orphan = srp->orphan;
1038 rinfo[val].sg_io_owned =
1039 srp->sg_io_owned;
1040 rinfo[val].pack_id =
1041 srp->header.pack_id;
1042 rinfo[val].usr_ptr =
1043 srp->header.usr_ptr;
1044 }
1045 }
1046 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1047 result = __copy_to_user(p, rinfo,
1048 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1049 result = result ? -EFAULT : 0;
1050 kfree(rinfo);
1051 return result;
1052 }
1053 case SG_EMULATED_HOST:
1054 if (atomic_read(&sdp->detaching))
1055 return -ENODEV;
1056 return put_user(sdp->device->host->hostt->emulated, ip);
1057 case SCSI_IOCTL_SEND_COMMAND:
1058 if (atomic_read(&sdp->detaching))
1059 return -ENODEV;
1060 if (read_only) {
1061 unsigned char opcode = WRITE_6;
1062 Scsi_Ioctl_Command __user *siocp = p;
1063
1064 if (copy_from_user(&opcode, siocp->data, 1))
1065 return -EFAULT;
1066 if (sg_allow_access(filp, &opcode))
1067 return -EPERM;
1068 }
1069 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1070 case SG_SET_DEBUG:
1071 result = get_user(val, ip);
1072 if (result)
1073 return result;
1074 sdp->sgdebug = (char) val;
1075 return 0;
1076 case BLKSECTGET:
1077 return put_user(max_sectors_bytes(sdp->device->request_queue),
1078 ip);
1079 case BLKTRACESETUP:
1080 return blk_trace_setup(sdp->device->request_queue,
1081 sdp->disk->disk_name,
1082 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1083 NULL,
1084 (char *)arg);
1085 case BLKTRACESTART:
1086 return blk_trace_startstop(sdp->device->request_queue, 1);
1087 case BLKTRACESTOP:
1088 return blk_trace_startstop(sdp->device->request_queue, 0);
1089 case BLKTRACETEARDOWN:
1090 return blk_trace_remove(sdp->device->request_queue);
1091 case SCSI_IOCTL_GET_IDLUN:
1092 case SCSI_IOCTL_GET_BUS_NUMBER:
1093 case SCSI_IOCTL_PROBE_HOST:
1094 case SG_GET_TRANSFORM:
1095 case SG_SCSI_RESET:
1096 if (atomic_read(&sdp->detaching))
1097 return -ENODEV;
1098 break;
1099 default:
1100 if (read_only)
1101 return -EPERM; /* don't know so take safe approach */
1102 break;
1103 }
1104
1105 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1106 cmd_in, filp->f_flags & O_NDELAY);
1107 if (result)
1108 return result;
1109 return scsi_ioctl(sdp->device, cmd_in, p);
1110 }
1111
1112 #ifdef CONFIG_COMPAT
1113 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1114 {
1115 Sg_device *sdp;
1116 Sg_fd *sfp;
1117 struct scsi_device *sdev;
1118
1119 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1120 return -ENXIO;
1121
1122 sdev = sdp->device;
1123 if (sdev->host->hostt->compat_ioctl) {
1124 int ret;
1125
1126 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1127
1128 return ret;
1129 }
1130
1131 return -ENOIOCTLCMD;
1132 }
1133 #endif
1134
1135 static unsigned int
1136 sg_poll(struct file *filp, poll_table * wait)
1137 {
1138 unsigned int res = 0;
1139 Sg_device *sdp;
1140 Sg_fd *sfp;
1141 Sg_request *srp;
1142 int count = 0;
1143 unsigned long iflags;
1144
1145 sfp = filp->private_data;
1146 if (!sfp)
1147 return POLLERR;
1148 sdp = sfp->parentdp;
1149 if (!sdp)
1150 return POLLERR;
1151 poll_wait(filp, &sfp->read_wait, wait);
1152 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1153 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1154 /* if any read waiting, flag it */
1155 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1156 res = POLLIN | POLLRDNORM;
1157 ++count;
1158 }
1159 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1160
1161 if (atomic_read(&sdp->detaching))
1162 res |= POLLHUP;
1163 else if (!sfp->cmd_q) {
1164 if (0 == count)
1165 res |= POLLOUT | POLLWRNORM;
1166 } else if (count < SG_MAX_QUEUE)
1167 res |= POLLOUT | POLLWRNORM;
1168 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1169 "sg_poll: res=0x%x\n", (int) res));
1170 return res;
1171 }
1172
1173 static int
1174 sg_fasync(int fd, struct file *filp, int mode)
1175 {
1176 Sg_device *sdp;
1177 Sg_fd *sfp;
1178
1179 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1180 return -ENXIO;
1181 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1182 "sg_fasync: mode=%d\n", mode));
1183
1184 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1185 }
1186
1187 static int
1188 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1189 {
1190 Sg_fd *sfp;
1191 unsigned long offset, len, sa;
1192 Sg_scatter_hold *rsv_schp;
1193 int k, length;
1194
1195 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1196 return VM_FAULT_SIGBUS;
1197 rsv_schp = &sfp->reserve;
1198 offset = vmf->pgoff << PAGE_SHIFT;
1199 if (offset >= rsv_schp->bufflen)
1200 return VM_FAULT_SIGBUS;
1201 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1202 "sg_vma_fault: offset=%lu, scatg=%d\n",
1203 offset, rsv_schp->k_use_sg));
1204 sa = vma->vm_start;
1205 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1206 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1207 len = vma->vm_end - sa;
1208 len = (len < length) ? len : length;
1209 if (offset < len) {
1210 struct page *page = nth_page(rsv_schp->pages[k],
1211 offset >> PAGE_SHIFT);
1212 get_page(page); /* increment page count */
1213 vmf->page = page;
1214 return 0; /* success */
1215 }
1216 sa += len;
1217 offset -= len;
1218 }
1219
1220 return VM_FAULT_SIGBUS;
1221 }
1222
1223 static const struct vm_operations_struct sg_mmap_vm_ops = {
1224 .fault = sg_vma_fault,
1225 };
1226
1227 static int
1228 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1229 {
1230 Sg_fd *sfp;
1231 unsigned long req_sz, len, sa;
1232 Sg_scatter_hold *rsv_schp;
1233 int k, length;
1234
1235 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1236 return -ENXIO;
1237 req_sz = vma->vm_end - vma->vm_start;
1238 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1239 "sg_mmap starting, vm_start=%p, len=%d\n",
1240 (void *) vma->vm_start, (int) req_sz));
1241 if (vma->vm_pgoff)
1242 return -EINVAL; /* want no offset */
1243 rsv_schp = &sfp->reserve;
1244 if (req_sz > rsv_schp->bufflen)
1245 return -ENOMEM; /* cannot map more than reserved buffer */
1246
1247 sa = vma->vm_start;
1248 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1249 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1250 len = vma->vm_end - sa;
1251 len = (len < length) ? len : length;
1252 sa += len;
1253 }
1254
1255 sfp->mmap_called = 1;
1256 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1257 vma->vm_private_data = sfp;
1258 vma->vm_ops = &sg_mmap_vm_ops;
1259 return 0;
1260 }
1261
1262 static void
1263 sg_rq_end_io_usercontext(struct work_struct *work)
1264 {
1265 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1266 struct sg_fd *sfp = srp->parentfp;
1267
1268 sg_finish_rem_req(srp);
1269 kref_put(&sfp->f_ref, sg_remove_sfp);
1270 }
1271
1272 /*
1273 * This function is a "bottom half" handler that is called by the mid
1274 * level when a command is completed (or has failed).
1275 */
1276 static void
1277 sg_rq_end_io(struct request *rq, int uptodate)
1278 {
1279 struct sg_request *srp = rq->end_io_data;
1280 struct scsi_request *req = scsi_req(rq);
1281 Sg_device *sdp;
1282 Sg_fd *sfp;
1283 unsigned long iflags;
1284 unsigned int ms;
1285 char *sense;
1286 int result, resid, done = 1;
1287
1288 if (WARN_ON(srp->done != 0))
1289 return;
1290
1291 sfp = srp->parentfp;
1292 if (WARN_ON(sfp == NULL))
1293 return;
1294
1295 sdp = sfp->parentdp;
1296 if (unlikely(atomic_read(&sdp->detaching)))
1297 pr_info("%s: device detaching\n", __func__);
1298
1299 sense = req->sense;
1300 result = rq->errors;
1301 resid = req->resid_len;
1302
1303 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1304 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1305 srp->header.pack_id, result));
1306 srp->header.resid = resid;
1307 ms = jiffies_to_msecs(jiffies);
1308 srp->header.duration = (ms > srp->header.duration) ?
1309 (ms - srp->header.duration) : 0;
1310 if (0 != result) {
1311 struct scsi_sense_hdr sshdr;
1312
1313 srp->header.status = 0xff & result;
1314 srp->header.masked_status = status_byte(result);
1315 srp->header.msg_status = msg_byte(result);
1316 srp->header.host_status = host_byte(result);
1317 srp->header.driver_status = driver_byte(result);
1318 if ((sdp->sgdebug > 0) &&
1319 ((CHECK_CONDITION == srp->header.masked_status) ||
1320 (COMMAND_TERMINATED == srp->header.masked_status)))
1321 __scsi_print_sense(sdp->device, __func__, sense,
1322 SCSI_SENSE_BUFFERSIZE);
1323
1324 /* Following if statement is a patch supplied by Eric Youngdale */
1325 if (driver_byte(result) != 0
1326 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1327 && !scsi_sense_is_deferred(&sshdr)
1328 && sshdr.sense_key == UNIT_ATTENTION
1329 && sdp->device->removable) {
1330 /* Detected possible disc change. Set the bit - this */
1331 /* may be used if there are filesystems using this device */
1332 sdp->device->changed = 1;
1333 }
1334 }
1335
1336 if (req->sense_len)
1337 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1338
1339 /* Rely on write phase to clean out srp status values, so no "else" */
1340
1341 /*
1342 * Free the request as soon as it is complete so that its resources
1343 * can be reused without waiting for userspace to read() the
1344 * result. But keep the associated bio (if any) around until
1345 * blk_rq_unmap_user() can be called from user context.
1346 */
1347 srp->rq = NULL;
1348 scsi_req_free_cmd(scsi_req(rq));
1349 __blk_put_request(rq->q, rq);
1350
1351 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1352 if (unlikely(srp->orphan)) {
1353 if (sfp->keep_orphan)
1354 srp->sg_io_owned = 0;
1355 else
1356 done = 0;
1357 }
1358 srp->done = done;
1359 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1360
1361 if (likely(done)) {
1362 /* Now wake up any sg_read() that is waiting for this
1363 * packet.
1364 */
1365 wake_up_interruptible(&sfp->read_wait);
1366 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1367 kref_put(&sfp->f_ref, sg_remove_sfp);
1368 } else {
1369 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1370 schedule_work(&srp->ew.work);
1371 }
1372 }
1373
1374 static const struct file_operations sg_fops = {
1375 .owner = THIS_MODULE,
1376 .read = sg_read,
1377 .write = sg_write,
1378 .poll = sg_poll,
1379 .unlocked_ioctl = sg_ioctl,
1380 #ifdef CONFIG_COMPAT
1381 .compat_ioctl = sg_compat_ioctl,
1382 #endif
1383 .open = sg_open,
1384 .mmap = sg_mmap,
1385 .release = sg_release,
1386 .fasync = sg_fasync,
1387 .llseek = no_llseek,
1388 };
1389
1390 static struct class *sg_sysfs_class;
1391
1392 static int sg_sysfs_valid = 0;
1393
1394 static Sg_device *
1395 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1396 {
1397 struct request_queue *q = scsidp->request_queue;
1398 Sg_device *sdp;
1399 unsigned long iflags;
1400 int error;
1401 u32 k;
1402
1403 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1404 if (!sdp) {
1405 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1406 "failure\n", __func__);
1407 return ERR_PTR(-ENOMEM);
1408 }
1409
1410 idr_preload(GFP_KERNEL);
1411 write_lock_irqsave(&sg_index_lock, iflags);
1412
1413 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1414 if (error < 0) {
1415 if (error == -ENOSPC) {
1416 sdev_printk(KERN_WARNING, scsidp,
1417 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1418 scsidp->type, SG_MAX_DEVS - 1);
1419 error = -ENODEV;
1420 } else {
1421 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1422 "allocation Sg_device failure: %d\n",
1423 __func__, error);
1424 }
1425 goto out_unlock;
1426 }
1427 k = error;
1428
1429 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1430 "sg_alloc: dev=%d \n", k));
1431 sprintf(disk->disk_name, "sg%d", k);
1432 disk->first_minor = k;
1433 sdp->disk = disk;
1434 sdp->device = scsidp;
1435 mutex_init(&sdp->open_rel_lock);
1436 INIT_LIST_HEAD(&sdp->sfds);
1437 init_waitqueue_head(&sdp->open_wait);
1438 atomic_set(&sdp->detaching, 0);
1439 rwlock_init(&sdp->sfd_lock);
1440 sdp->sg_tablesize = queue_max_segments(q);
1441 sdp->index = k;
1442 kref_init(&sdp->d_ref);
1443 error = 0;
1444
1445 out_unlock:
1446 write_unlock_irqrestore(&sg_index_lock, iflags);
1447 idr_preload_end();
1448
1449 if (error) {
1450 kfree(sdp);
1451 return ERR_PTR(error);
1452 }
1453 return sdp;
1454 }
1455
1456 static int
1457 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1458 {
1459 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1460 struct gendisk *disk;
1461 Sg_device *sdp = NULL;
1462 struct cdev * cdev = NULL;
1463 int error;
1464 unsigned long iflags;
1465
1466 disk = alloc_disk(1);
1467 if (!disk) {
1468 pr_warn("%s: alloc_disk failed\n", __func__);
1469 return -ENOMEM;
1470 }
1471 disk->major = SCSI_GENERIC_MAJOR;
1472
1473 error = -ENOMEM;
1474 cdev = cdev_alloc();
1475 if (!cdev) {
1476 pr_warn("%s: cdev_alloc failed\n", __func__);
1477 goto out;
1478 }
1479 cdev->owner = THIS_MODULE;
1480 cdev->ops = &sg_fops;
1481
1482 sdp = sg_alloc(disk, scsidp);
1483 if (IS_ERR(sdp)) {
1484 pr_warn("%s: sg_alloc failed\n", __func__);
1485 error = PTR_ERR(sdp);
1486 goto out;
1487 }
1488
1489 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1490 if (error)
1491 goto cdev_add_err;
1492
1493 sdp->cdev = cdev;
1494 if (sg_sysfs_valid) {
1495 struct device *sg_class_member;
1496
1497 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1498 MKDEV(SCSI_GENERIC_MAJOR,
1499 sdp->index),
1500 sdp, "%s", disk->disk_name);
1501 if (IS_ERR(sg_class_member)) {
1502 pr_err("%s: device_create failed\n", __func__);
1503 error = PTR_ERR(sg_class_member);
1504 goto cdev_add_err;
1505 }
1506 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1507 &sg_class_member->kobj, "generic");
1508 if (error)
1509 pr_err("%s: unable to make symlink 'generic' back "
1510 "to sg%d\n", __func__, sdp->index);
1511 } else
1512 pr_warn("%s: sg_sys Invalid\n", __func__);
1513
1514 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1515 "type %d\n", sdp->index, scsidp->type);
1516
1517 dev_set_drvdata(cl_dev, sdp);
1518
1519 return 0;
1520
1521 cdev_add_err:
1522 write_lock_irqsave(&sg_index_lock, iflags);
1523 idr_remove(&sg_index_idr, sdp->index);
1524 write_unlock_irqrestore(&sg_index_lock, iflags);
1525 kfree(sdp);
1526
1527 out:
1528 put_disk(disk);
1529 if (cdev)
1530 cdev_del(cdev);
1531 return error;
1532 }
1533
1534 static void
1535 sg_device_destroy(struct kref *kref)
1536 {
1537 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1538 unsigned long flags;
1539
1540 /* CAUTION! Note that the device can still be found via idr_find()
1541 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1542 * any other cleanup.
1543 */
1544
1545 write_lock_irqsave(&sg_index_lock, flags);
1546 idr_remove(&sg_index_idr, sdp->index);
1547 write_unlock_irqrestore(&sg_index_lock, flags);
1548
1549 SCSI_LOG_TIMEOUT(3,
1550 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1551
1552 put_disk(sdp->disk);
1553 kfree(sdp);
1554 }
1555
1556 static void
1557 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1558 {
1559 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1560 Sg_device *sdp = dev_get_drvdata(cl_dev);
1561 unsigned long iflags;
1562 Sg_fd *sfp;
1563 int val;
1564
1565 if (!sdp)
1566 return;
1567 /* want sdp->detaching non-zero as soon as possible */
1568 val = atomic_inc_return(&sdp->detaching);
1569 if (val > 1)
1570 return; /* only want to do following once per device */
1571
1572 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1573 "%s\n", __func__));
1574
1575 read_lock_irqsave(&sdp->sfd_lock, iflags);
1576 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1577 wake_up_interruptible_all(&sfp->read_wait);
1578 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1579 }
1580 wake_up_interruptible_all(&sdp->open_wait);
1581 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1582
1583 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1584 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1585 cdev_del(sdp->cdev);
1586 sdp->cdev = NULL;
1587
1588 kref_put(&sdp->d_ref, sg_device_destroy);
1589 }
1590
1591 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1592 module_param_named(def_reserved_size, def_reserved_size, int,
1593 S_IRUGO | S_IWUSR);
1594 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1595
1596 MODULE_AUTHOR("Douglas Gilbert");
1597 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1598 MODULE_LICENSE("GPL");
1599 MODULE_VERSION(SG_VERSION_STR);
1600 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1601
1602 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1603 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1604 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1605 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1606
1607 static int __init
1608 init_sg(void)
1609 {
1610 int rc;
1611
1612 if (scatter_elem_sz < PAGE_SIZE) {
1613 scatter_elem_sz = PAGE_SIZE;
1614 scatter_elem_sz_prev = scatter_elem_sz;
1615 }
1616 if (def_reserved_size >= 0)
1617 sg_big_buff = def_reserved_size;
1618 else
1619 def_reserved_size = sg_big_buff;
1620
1621 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1622 SG_MAX_DEVS, "sg");
1623 if (rc)
1624 return rc;
1625 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1626 if ( IS_ERR(sg_sysfs_class) ) {
1627 rc = PTR_ERR(sg_sysfs_class);
1628 goto err_out;
1629 }
1630 sg_sysfs_valid = 1;
1631 rc = scsi_register_interface(&sg_interface);
1632 if (0 == rc) {
1633 #ifdef CONFIG_SCSI_PROC_FS
1634 sg_proc_init();
1635 #endif /* CONFIG_SCSI_PROC_FS */
1636 return 0;
1637 }
1638 class_destroy(sg_sysfs_class);
1639 err_out:
1640 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1641 return rc;
1642 }
1643
1644 static void __exit
1645 exit_sg(void)
1646 {
1647 #ifdef CONFIG_SCSI_PROC_FS
1648 sg_proc_cleanup();
1649 #endif /* CONFIG_SCSI_PROC_FS */
1650 scsi_unregister_interface(&sg_interface);
1651 class_destroy(sg_sysfs_class);
1652 sg_sysfs_valid = 0;
1653 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1654 SG_MAX_DEVS);
1655 idr_destroy(&sg_index_idr);
1656 }
1657
1658 static int
1659 sg_start_req(Sg_request *srp, unsigned char *cmd)
1660 {
1661 int res;
1662 struct request *rq;
1663 struct scsi_request *req;
1664 Sg_fd *sfp = srp->parentfp;
1665 sg_io_hdr_t *hp = &srp->header;
1666 int dxfer_len = (int) hp->dxfer_len;
1667 int dxfer_dir = hp->dxfer_direction;
1668 unsigned int iov_count = hp->iovec_count;
1669 Sg_scatter_hold *req_schp = &srp->data;
1670 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1671 struct request_queue *q = sfp->parentdp->device->request_queue;
1672 struct rq_map_data *md, map_data;
1673 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1674 unsigned char *long_cmdp = NULL;
1675
1676 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1677 "sg_start_req: dxfer_len=%d\n",
1678 dxfer_len));
1679
1680 if (hp->cmd_len > BLK_MAX_CDB) {
1681 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1682 if (!long_cmdp)
1683 return -ENOMEM;
1684 }
1685
1686 /*
1687 * NOTE
1688 *
1689 * With scsi-mq enabled, there are a fixed number of preallocated
1690 * requests equal in number to shost->can_queue. If all of the
1691 * preallocated requests are already in use, then using GFP_ATOMIC with
1692 * blk_get_request() will return -EWOULDBLOCK, whereas using GFP_KERNEL
1693 * will cause blk_get_request() to sleep until an active command
1694 * completes, freeing up a request. Neither option is ideal, but
1695 * GFP_KERNEL is the better choice to prevent userspace from getting an
1696 * unexpected EWOULDBLOCK.
1697 *
1698 * With scsi-mq disabled, blk_get_request() with GFP_KERNEL usually
1699 * does not sleep except under memory pressure.
1700 */
1701 rq = blk_get_request(q, rw, GFP_KERNEL);
1702 if (IS_ERR(rq)) {
1703 kfree(long_cmdp);
1704 return PTR_ERR(rq);
1705 }
1706 req = scsi_req(rq);
1707
1708 scsi_req_init(rq);
1709
1710 if (hp->cmd_len > BLK_MAX_CDB)
1711 req->cmd = long_cmdp;
1712 memcpy(req->cmd, cmd, hp->cmd_len);
1713 req->cmd_len = hp->cmd_len;
1714
1715 srp->rq = rq;
1716 rq->end_io_data = srp;
1717 rq->retries = SG_DEFAULT_RETRIES;
1718
1719 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1720 return 0;
1721
1722 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1723 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1724 !sfp->parentdp->device->host->unchecked_isa_dma &&
1725 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1726 md = NULL;
1727 else
1728 md = &map_data;
1729
1730 if (md) {
1731 if (!sg_res_in_use(sfp) && dxfer_len <= rsv_schp->bufflen)
1732 sg_link_reserve(sfp, srp, dxfer_len);
1733 else {
1734 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1735 if (res)
1736 return res;
1737 }
1738
1739 md->pages = req_schp->pages;
1740 md->page_order = req_schp->page_order;
1741 md->nr_entries = req_schp->k_use_sg;
1742 md->offset = 0;
1743 md->null_mapped = hp->dxferp ? 0 : 1;
1744 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1745 md->from_user = 1;
1746 else
1747 md->from_user = 0;
1748 }
1749
1750 if (iov_count) {
1751 struct iovec *iov = NULL;
1752 struct iov_iter i;
1753
1754 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1755 if (res < 0)
1756 return res;
1757
1758 iov_iter_truncate(&i, hp->dxfer_len);
1759
1760 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1761 kfree(iov);
1762 } else
1763 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1764 hp->dxfer_len, GFP_ATOMIC);
1765
1766 if (!res) {
1767 srp->bio = rq->bio;
1768
1769 if (!md) {
1770 req_schp->dio_in_use = 1;
1771 hp->info |= SG_INFO_DIRECT_IO;
1772 }
1773 }
1774 return res;
1775 }
1776
1777 static int
1778 sg_finish_rem_req(Sg_request *srp)
1779 {
1780 int ret = 0;
1781
1782 Sg_fd *sfp = srp->parentfp;
1783 Sg_scatter_hold *req_schp = &srp->data;
1784
1785 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1786 "sg_finish_rem_req: res_used=%d\n",
1787 (int) srp->res_used));
1788 if (srp->bio)
1789 ret = blk_rq_unmap_user(srp->bio);
1790
1791 if (srp->rq) {
1792 scsi_req_free_cmd(scsi_req(srp->rq));
1793 blk_put_request(srp->rq);
1794 }
1795
1796 if (srp->res_used)
1797 sg_unlink_reserve(sfp, srp);
1798 else
1799 sg_remove_scat(sfp, req_schp);
1800
1801 sg_remove_request(sfp, srp);
1802
1803 return ret;
1804 }
1805
1806 static int
1807 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1808 {
1809 int sg_bufflen = tablesize * sizeof(struct page *);
1810 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1811
1812 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1813 if (!schp->pages)
1814 return -ENOMEM;
1815 schp->sglist_len = sg_bufflen;
1816 return tablesize; /* number of scat_gath elements allocated */
1817 }
1818
1819 static int
1820 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1821 {
1822 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1823 int sg_tablesize = sfp->parentdp->sg_tablesize;
1824 int blk_size = buff_size, order;
1825 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1826
1827 if (blk_size < 0)
1828 return -EFAULT;
1829 if (0 == blk_size)
1830 ++blk_size; /* don't know why */
1831 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1832 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1833 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1834 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1835 buff_size, blk_size));
1836
1837 /* N.B. ret_sz carried into this block ... */
1838 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1839 if (mx_sc_elems < 0)
1840 return mx_sc_elems; /* most likely -ENOMEM */
1841
1842 num = scatter_elem_sz;
1843 if (unlikely(num != scatter_elem_sz_prev)) {
1844 if (num < PAGE_SIZE) {
1845 scatter_elem_sz = PAGE_SIZE;
1846 scatter_elem_sz_prev = PAGE_SIZE;
1847 } else
1848 scatter_elem_sz_prev = num;
1849 }
1850
1851 if (sfp->low_dma)
1852 gfp_mask |= GFP_DMA;
1853
1854 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1855 gfp_mask |= __GFP_ZERO;
1856
1857 order = get_order(num);
1858 retry:
1859 ret_sz = 1 << (PAGE_SHIFT + order);
1860
1861 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1862 k++, rem_sz -= ret_sz) {
1863
1864 num = (rem_sz > scatter_elem_sz_prev) ?
1865 scatter_elem_sz_prev : rem_sz;
1866
1867 schp->pages[k] = alloc_pages(gfp_mask, order);
1868 if (!schp->pages[k])
1869 goto out;
1870
1871 if (num == scatter_elem_sz_prev) {
1872 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1873 scatter_elem_sz = ret_sz;
1874 scatter_elem_sz_prev = ret_sz;
1875 }
1876 }
1877
1878 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1879 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1880 k, num, ret_sz));
1881 } /* end of for loop */
1882
1883 schp->page_order = order;
1884 schp->k_use_sg = k;
1885 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1886 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1887 k, rem_sz));
1888
1889 schp->bufflen = blk_size;
1890 if (rem_sz > 0) /* must have failed */
1891 return -ENOMEM;
1892 return 0;
1893 out:
1894 for (i = 0; i < k; i++)
1895 __free_pages(schp->pages[i], order);
1896
1897 if (--order >= 0)
1898 goto retry;
1899
1900 return -ENOMEM;
1901 }
1902
1903 static void
1904 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1905 {
1906 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1907 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1908 if (schp->pages && schp->sglist_len > 0) {
1909 if (!schp->dio_in_use) {
1910 int k;
1911
1912 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1913 SCSI_LOG_TIMEOUT(5,
1914 sg_printk(KERN_INFO, sfp->parentdp,
1915 "sg_remove_scat: k=%d, pg=0x%p\n",
1916 k, schp->pages[k]));
1917 __free_pages(schp->pages[k], schp->page_order);
1918 }
1919
1920 kfree(schp->pages);
1921 }
1922 }
1923 memset(schp, 0, sizeof (*schp));
1924 }
1925
1926 static int
1927 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1928 {
1929 Sg_scatter_hold *schp = &srp->data;
1930 int k, num;
1931
1932 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1933 "sg_read_oxfer: num_read_xfer=%d\n",
1934 num_read_xfer));
1935 if ((!outp) || (num_read_xfer <= 0))
1936 return 0;
1937
1938 num = 1 << (PAGE_SHIFT + schp->page_order);
1939 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1940 if (num > num_read_xfer) {
1941 if (__copy_to_user(outp, page_address(schp->pages[k]),
1942 num_read_xfer))
1943 return -EFAULT;
1944 break;
1945 } else {
1946 if (__copy_to_user(outp, page_address(schp->pages[k]),
1947 num))
1948 return -EFAULT;
1949 num_read_xfer -= num;
1950 if (num_read_xfer <= 0)
1951 break;
1952 outp += num;
1953 }
1954 }
1955
1956 return 0;
1957 }
1958
1959 static void
1960 sg_build_reserve(Sg_fd * sfp, int req_size)
1961 {
1962 Sg_scatter_hold *schp = &sfp->reserve;
1963
1964 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1965 "sg_build_reserve: req_size=%d\n", req_size));
1966 do {
1967 if (req_size < PAGE_SIZE)
1968 req_size = PAGE_SIZE;
1969 if (0 == sg_build_indirect(schp, sfp, req_size))
1970 return;
1971 else
1972 sg_remove_scat(sfp, schp);
1973 req_size >>= 1; /* divide by 2 */
1974 } while (req_size > (PAGE_SIZE / 2));
1975 }
1976
1977 static void
1978 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1979 {
1980 Sg_scatter_hold *req_schp = &srp->data;
1981 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1982 int k, num, rem;
1983
1984 srp->res_used = 1;
1985 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1986 "sg_link_reserve: size=%d\n", size));
1987 rem = size;
1988
1989 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1990 for (k = 0; k < rsv_schp->k_use_sg; k++) {
1991 if (rem <= num) {
1992 req_schp->k_use_sg = k + 1;
1993 req_schp->sglist_len = rsv_schp->sglist_len;
1994 req_schp->pages = rsv_schp->pages;
1995
1996 req_schp->bufflen = size;
1997 req_schp->page_order = rsv_schp->page_order;
1998 break;
1999 } else
2000 rem -= num;
2001 }
2002
2003 if (k >= rsv_schp->k_use_sg)
2004 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2005 "sg_link_reserve: BAD size\n"));
2006 }
2007
2008 static void
2009 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2010 {
2011 Sg_scatter_hold *req_schp = &srp->data;
2012
2013 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2014 "sg_unlink_reserve: req->k_use_sg=%d\n",
2015 (int) req_schp->k_use_sg));
2016 req_schp->k_use_sg = 0;
2017 req_schp->bufflen = 0;
2018 req_schp->pages = NULL;
2019 req_schp->page_order = 0;
2020 req_schp->sglist_len = 0;
2021 sfp->save_scat_len = 0;
2022 srp->res_used = 0;
2023 }
2024
2025 static Sg_request *
2026 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2027 {
2028 Sg_request *resp;
2029 unsigned long iflags;
2030
2031 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2032 for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2033 /* look for requests that are ready + not SG_IO owned */
2034 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2035 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2036 resp->done = 2; /* guard against other readers */
2037 break;
2038 }
2039 }
2040 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2041 return resp;
2042 }
2043
2044 /* always adds to end of list */
2045 static Sg_request *
2046 sg_add_request(Sg_fd * sfp)
2047 {
2048 int k;
2049 unsigned long iflags;
2050 Sg_request *resp;
2051 Sg_request *rp = sfp->req_arr;
2052
2053 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2054 resp = sfp->headrp;
2055 if (!resp) {
2056 memset(rp, 0, sizeof (Sg_request));
2057 rp->parentfp = sfp;
2058 resp = rp;
2059 sfp->headrp = resp;
2060 } else {
2061 if (0 == sfp->cmd_q)
2062 resp = NULL; /* command queuing disallowed */
2063 else {
2064 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2065 if (!rp->parentfp)
2066 break;
2067 }
2068 if (k < SG_MAX_QUEUE) {
2069 memset(rp, 0, sizeof (Sg_request));
2070 rp->parentfp = sfp;
2071 while (resp->nextrp)
2072 resp = resp->nextrp;
2073 resp->nextrp = rp;
2074 resp = rp;
2075 } else
2076 resp = NULL;
2077 }
2078 }
2079 if (resp) {
2080 resp->nextrp = NULL;
2081 resp->header.duration = jiffies_to_msecs(jiffies);
2082 }
2083 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2084 return resp;
2085 }
2086
2087 /* Return of 1 for found; 0 for not found */
2088 static int
2089 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2090 {
2091 Sg_request *prev_rp;
2092 Sg_request *rp;
2093 unsigned long iflags;
2094 int res = 0;
2095
2096 if ((!sfp) || (!srp) || (!sfp->headrp))
2097 return res;
2098 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2099 prev_rp = sfp->headrp;
2100 if (srp == prev_rp) {
2101 sfp->headrp = prev_rp->nextrp;
2102 prev_rp->parentfp = NULL;
2103 res = 1;
2104 } else {
2105 while ((rp = prev_rp->nextrp)) {
2106 if (srp == rp) {
2107 prev_rp->nextrp = rp->nextrp;
2108 rp->parentfp = NULL;
2109 res = 1;
2110 break;
2111 }
2112 prev_rp = rp;
2113 }
2114 }
2115 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2116 return res;
2117 }
2118
2119 static Sg_fd *
2120 sg_add_sfp(Sg_device * sdp)
2121 {
2122 Sg_fd *sfp;
2123 unsigned long iflags;
2124 int bufflen;
2125
2126 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2127 if (!sfp)
2128 return ERR_PTR(-ENOMEM);
2129
2130 init_waitqueue_head(&sfp->read_wait);
2131 rwlock_init(&sfp->rq_list_lock);
2132
2133 kref_init(&sfp->f_ref);
2134 sfp->timeout = SG_DEFAULT_TIMEOUT;
2135 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2136 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2137 sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2138 sdp->device->host->unchecked_isa_dma : 1;
2139 sfp->cmd_q = SG_DEF_COMMAND_Q;
2140 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2141 sfp->parentdp = sdp;
2142 write_lock_irqsave(&sdp->sfd_lock, iflags);
2143 if (atomic_read(&sdp->detaching)) {
2144 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2145 return ERR_PTR(-ENODEV);
2146 }
2147 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2148 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2149 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2150 "sg_add_sfp: sfp=0x%p\n", sfp));
2151 if (unlikely(sg_big_buff != def_reserved_size))
2152 sg_big_buff = def_reserved_size;
2153
2154 bufflen = min_t(int, sg_big_buff,
2155 max_sectors_bytes(sdp->device->request_queue));
2156 sg_build_reserve(sfp, bufflen);
2157 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2158 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2159 sfp->reserve.bufflen,
2160 sfp->reserve.k_use_sg));
2161
2162 kref_get(&sdp->d_ref);
2163 __module_get(THIS_MODULE);
2164 return sfp;
2165 }
2166
2167 static void
2168 sg_remove_sfp_usercontext(struct work_struct *work)
2169 {
2170 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2171 struct sg_device *sdp = sfp->parentdp;
2172
2173 /* Cleanup any responses which were never read(). */
2174 while (sfp->headrp)
2175 sg_finish_rem_req(sfp->headrp);
2176
2177 if (sfp->reserve.bufflen > 0) {
2178 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2179 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2180 (int) sfp->reserve.bufflen,
2181 (int) sfp->reserve.k_use_sg));
2182 sg_remove_scat(sfp, &sfp->reserve);
2183 }
2184
2185 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2186 "sg_remove_sfp: sfp=0x%p\n", sfp));
2187 kfree(sfp);
2188
2189 scsi_device_put(sdp->device);
2190 kref_put(&sdp->d_ref, sg_device_destroy);
2191 module_put(THIS_MODULE);
2192 }
2193
2194 static void
2195 sg_remove_sfp(struct kref *kref)
2196 {
2197 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2198 struct sg_device *sdp = sfp->parentdp;
2199 unsigned long iflags;
2200
2201 write_lock_irqsave(&sdp->sfd_lock, iflags);
2202 list_del(&sfp->sfd_siblings);
2203 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2204
2205 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2206 schedule_work(&sfp->ew.work);
2207 }
2208
2209 static int
2210 sg_res_in_use(Sg_fd * sfp)
2211 {
2212 const Sg_request *srp;
2213 unsigned long iflags;
2214
2215 read_lock_irqsave(&sfp->rq_list_lock, iflags);
2216 for (srp = sfp->headrp; srp; srp = srp->nextrp)
2217 if (srp->res_used)
2218 break;
2219 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2220 return srp ? 1 : 0;
2221 }
2222
2223 #ifdef CONFIG_SCSI_PROC_FS
2224 static int
2225 sg_idr_max_id(int id, void *p, void *data)
2226 {
2227 int *k = data;
2228
2229 if (*k < id)
2230 *k = id;
2231
2232 return 0;
2233 }
2234
2235 static int
2236 sg_last_dev(void)
2237 {
2238 int k = -1;
2239 unsigned long iflags;
2240
2241 read_lock_irqsave(&sg_index_lock, iflags);
2242 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2243 read_unlock_irqrestore(&sg_index_lock, iflags);
2244 return k + 1; /* origin 1 */
2245 }
2246 #endif
2247
2248 /* must be called with sg_index_lock held */
2249 static Sg_device *sg_lookup_dev(int dev)
2250 {
2251 return idr_find(&sg_index_idr, dev);
2252 }
2253
2254 static Sg_device *
2255 sg_get_dev(int dev)
2256 {
2257 struct sg_device *sdp;
2258 unsigned long flags;
2259
2260 read_lock_irqsave(&sg_index_lock, flags);
2261 sdp = sg_lookup_dev(dev);
2262 if (!sdp)
2263 sdp = ERR_PTR(-ENXIO);
2264 else if (atomic_read(&sdp->detaching)) {
2265 /* If sdp->detaching, then the refcount may already be 0, in
2266 * which case it would be a bug to do kref_get().
2267 */
2268 sdp = ERR_PTR(-ENODEV);
2269 } else
2270 kref_get(&sdp->d_ref);
2271 read_unlock_irqrestore(&sg_index_lock, flags);
2272
2273 return sdp;
2274 }
2275
2276 #ifdef CONFIG_SCSI_PROC_FS
2277
2278 static struct proc_dir_entry *sg_proc_sgp = NULL;
2279
2280 static char sg_proc_sg_dirname[] = "scsi/sg";
2281
2282 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2283
2284 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2285 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2286 size_t count, loff_t *off);
2287 static const struct file_operations adio_fops = {
2288 .owner = THIS_MODULE,
2289 .open = sg_proc_single_open_adio,
2290 .read = seq_read,
2291 .llseek = seq_lseek,
2292 .write = sg_proc_write_adio,
2293 .release = single_release,
2294 };
2295
2296 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2297 static ssize_t sg_proc_write_dressz(struct file *filp,
2298 const char __user *buffer, size_t count, loff_t *off);
2299 static const struct file_operations dressz_fops = {
2300 .owner = THIS_MODULE,
2301 .open = sg_proc_single_open_dressz,
2302 .read = seq_read,
2303 .llseek = seq_lseek,
2304 .write = sg_proc_write_dressz,
2305 .release = single_release,
2306 };
2307
2308 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2309 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2310 static const struct file_operations version_fops = {
2311 .owner = THIS_MODULE,
2312 .open = sg_proc_single_open_version,
2313 .read = seq_read,
2314 .llseek = seq_lseek,
2315 .release = single_release,
2316 };
2317
2318 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2319 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2320 static const struct file_operations devhdr_fops = {
2321 .owner = THIS_MODULE,
2322 .open = sg_proc_single_open_devhdr,
2323 .read = seq_read,
2324 .llseek = seq_lseek,
2325 .release = single_release,
2326 };
2327
2328 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2329 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2330 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2331 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2332 static void dev_seq_stop(struct seq_file *s, void *v);
2333 static const struct file_operations dev_fops = {
2334 .owner = THIS_MODULE,
2335 .open = sg_proc_open_dev,
2336 .read = seq_read,
2337 .llseek = seq_lseek,
2338 .release = seq_release,
2339 };
2340 static const struct seq_operations dev_seq_ops = {
2341 .start = dev_seq_start,
2342 .next = dev_seq_next,
2343 .stop = dev_seq_stop,
2344 .show = sg_proc_seq_show_dev,
2345 };
2346
2347 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2348 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2349 static const struct file_operations devstrs_fops = {
2350 .owner = THIS_MODULE,
2351 .open = sg_proc_open_devstrs,
2352 .read = seq_read,
2353 .llseek = seq_lseek,
2354 .release = seq_release,
2355 };
2356 static const struct seq_operations devstrs_seq_ops = {
2357 .start = dev_seq_start,
2358 .next = dev_seq_next,
2359 .stop = dev_seq_stop,
2360 .show = sg_proc_seq_show_devstrs,
2361 };
2362
2363 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2364 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2365 static const struct file_operations debug_fops = {
2366 .owner = THIS_MODULE,
2367 .open = sg_proc_open_debug,
2368 .read = seq_read,
2369 .llseek = seq_lseek,
2370 .release = seq_release,
2371 };
2372 static const struct seq_operations debug_seq_ops = {
2373 .start = dev_seq_start,
2374 .next = dev_seq_next,
2375 .stop = dev_seq_stop,
2376 .show = sg_proc_seq_show_debug,
2377 };
2378
2379
2380 struct sg_proc_leaf {
2381 const char * name;
2382 const struct file_operations * fops;
2383 };
2384
2385 static const struct sg_proc_leaf sg_proc_leaf_arr[] = {
2386 {"allow_dio", &adio_fops},
2387 {"debug", &debug_fops},
2388 {"def_reserved_size", &dressz_fops},
2389 {"device_hdr", &devhdr_fops},
2390 {"devices", &dev_fops},
2391 {"device_strs", &devstrs_fops},
2392 {"version", &version_fops}
2393 };
2394
2395 static int
2396 sg_proc_init(void)
2397 {
2398 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2399 int k;
2400
2401 sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2402 if (!sg_proc_sgp)
2403 return 1;
2404 for (k = 0; k < num_leaves; ++k) {
2405 const struct sg_proc_leaf *leaf = &sg_proc_leaf_arr[k];
2406 umode_t mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2407 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2408 }
2409 return 0;
2410 }
2411
2412 static void
2413 sg_proc_cleanup(void)
2414 {
2415 int k;
2416 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2417
2418 if (!sg_proc_sgp)
2419 return;
2420 for (k = 0; k < num_leaves; ++k)
2421 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2422 remove_proc_entry(sg_proc_sg_dirname, NULL);
2423 }
2424
2425
2426 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2427 {
2428 seq_printf(s, "%d\n", *((int *)s->private));
2429 return 0;
2430 }
2431
2432 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2433 {
2434 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2435 }
2436
2437 static ssize_t
2438 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2439 size_t count, loff_t *off)
2440 {
2441 int err;
2442 unsigned long num;
2443
2444 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2445 return -EACCES;
2446 err = kstrtoul_from_user(buffer, count, 0, &num);
2447 if (err)
2448 return err;
2449 sg_allow_dio = num ? 1 : 0;
2450 return count;
2451 }
2452
2453 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2454 {
2455 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2456 }
2457
2458 static ssize_t
2459 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2460 size_t count, loff_t *off)
2461 {
2462 int err;
2463 unsigned long k = ULONG_MAX;
2464
2465 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2466 return -EACCES;
2467
2468 err = kstrtoul_from_user(buffer, count, 0, &k);
2469 if (err)
2470 return err;
2471 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2472 sg_big_buff = k;
2473 return count;
2474 }
2475 return -ERANGE;
2476 }
2477
2478 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2479 {
2480 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2481 sg_version_date);
2482 return 0;
2483 }
2484
2485 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2486 {
2487 return single_open(file, sg_proc_seq_show_version, NULL);
2488 }
2489
2490 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2491 {
2492 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2493 return 0;
2494 }
2495
2496 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2497 {
2498 return single_open(file, sg_proc_seq_show_devhdr, NULL);
2499 }
2500
2501 struct sg_proc_deviter {
2502 loff_t index;
2503 size_t max;
2504 };
2505
2506 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2507 {
2508 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2509
2510 s->private = it;
2511 if (! it)
2512 return NULL;
2513
2514 it->index = *pos;
2515 it->max = sg_last_dev();
2516 if (it->index >= it->max)
2517 return NULL;
2518 return it;
2519 }
2520
2521 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2522 {
2523 struct sg_proc_deviter * it = s->private;
2524
2525 *pos = ++it->index;
2526 return (it->index < it->max) ? it : NULL;
2527 }
2528
2529 static void dev_seq_stop(struct seq_file *s, void *v)
2530 {
2531 kfree(s->private);
2532 }
2533
2534 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2535 {
2536 return seq_open(file, &dev_seq_ops);
2537 }
2538
2539 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2540 {
2541 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2542 Sg_device *sdp;
2543 struct scsi_device *scsidp;
2544 unsigned long iflags;
2545
2546 read_lock_irqsave(&sg_index_lock, iflags);
2547 sdp = it ? sg_lookup_dev(it->index) : NULL;
2548 if ((NULL == sdp) || (NULL == sdp->device) ||
2549 (atomic_read(&sdp->detaching)))
2550 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2551 else {
2552 scsidp = sdp->device;
2553 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2554 scsidp->host->host_no, scsidp->channel,
2555 scsidp->id, scsidp->lun, (int) scsidp->type,
2556 1,
2557 (int) scsidp->queue_depth,
2558 (int) atomic_read(&scsidp->device_busy),
2559 (int) scsi_device_online(scsidp));
2560 }
2561 read_unlock_irqrestore(&sg_index_lock, iflags);
2562 return 0;
2563 }
2564
2565 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2566 {
2567 return seq_open(file, &devstrs_seq_ops);
2568 }
2569
2570 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2571 {
2572 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2573 Sg_device *sdp;
2574 struct scsi_device *scsidp;
2575 unsigned long iflags;
2576
2577 read_lock_irqsave(&sg_index_lock, iflags);
2578 sdp = it ? sg_lookup_dev(it->index) : NULL;
2579 scsidp = sdp ? sdp->device : NULL;
2580 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2581 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2582 scsidp->vendor, scsidp->model, scsidp->rev);
2583 else
2584 seq_puts(s, "<no active device>\n");
2585 read_unlock_irqrestore(&sg_index_lock, iflags);
2586 return 0;
2587 }
2588
2589 /* must be called while holding sg_index_lock */
2590 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2591 {
2592 int k, m, new_interface, blen, usg;
2593 Sg_request *srp;
2594 Sg_fd *fp;
2595 const sg_io_hdr_t *hp;
2596 const char * cp;
2597 unsigned int ms;
2598
2599 k = 0;
2600 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2601 k++;
2602 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2603 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2604 "(res)sgat=%d low_dma=%d\n", k,
2605 jiffies_to_msecs(fp->timeout),
2606 fp->reserve.bufflen,
2607 (int) fp->reserve.k_use_sg,
2608 (int) fp->low_dma);
2609 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2610 (int) fp->cmd_q, (int) fp->force_packid,
2611 (int) fp->keep_orphan);
2612 for (m = 0, srp = fp->headrp;
2613 srp != NULL;
2614 ++m, srp = srp->nextrp) {
2615 hp = &srp->header;
2616 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2617 if (srp->res_used) {
2618 if (new_interface &&
2619 (SG_FLAG_MMAP_IO & hp->flags))
2620 cp = " mmap>> ";
2621 else
2622 cp = " rb>> ";
2623 } else {
2624 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2625 cp = " dio>> ";
2626 else
2627 cp = " ";
2628 }
2629 seq_puts(s, cp);
2630 blen = srp->data.bufflen;
2631 usg = srp->data.k_use_sg;
2632 seq_puts(s, srp->done ?
2633 ((1 == srp->done) ? "rcv:" : "fin:")
2634 : "act:");
2635 seq_printf(s, " id=%d blen=%d",
2636 srp->header.pack_id, blen);
2637 if (srp->done)
2638 seq_printf(s, " dur=%d", hp->duration);
2639 else {
2640 ms = jiffies_to_msecs(jiffies);
2641 seq_printf(s, " t_o/elap=%d/%d",
2642 (new_interface ? hp->timeout :
2643 jiffies_to_msecs(fp->timeout)),
2644 (ms > hp->duration ? ms - hp->duration : 0));
2645 }
2646 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2647 (int) srp->data.cmd_opcode);
2648 }
2649 if (0 == m)
2650 seq_puts(s, " No requests active\n");
2651 read_unlock(&fp->rq_list_lock);
2652 }
2653 }
2654
2655 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2656 {
2657 return seq_open(file, &debug_seq_ops);
2658 }
2659
2660 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2661 {
2662 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2663 Sg_device *sdp;
2664 unsigned long iflags;
2665
2666 if (it && (0 == it->index))
2667 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2668 (int)it->max, sg_big_buff);
2669
2670 read_lock_irqsave(&sg_index_lock, iflags);
2671 sdp = it ? sg_lookup_dev(it->index) : NULL;
2672 if (NULL == sdp)
2673 goto skip;
2674 read_lock(&sdp->sfd_lock);
2675 if (!list_empty(&sdp->sfds)) {
2676 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2677 if (atomic_read(&sdp->detaching))
2678 seq_puts(s, "detaching pending close ");
2679 else if (sdp->device) {
2680 struct scsi_device *scsidp = sdp->device;
2681
2682 seq_printf(s, "%d:%d:%d:%llu em=%d",
2683 scsidp->host->host_no,
2684 scsidp->channel, scsidp->id,
2685 scsidp->lun,
2686 scsidp->host->hostt->emulated);
2687 }
2688 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2689 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2690 sg_proc_debug_helper(s, sdp);
2691 }
2692 read_unlock(&sdp->sfd_lock);
2693 skip:
2694 read_unlock_irqrestore(&sg_index_lock, iflags);
2695 return 0;
2696 }
2697
2698 #endif /* CONFIG_SCSI_PROC_FS */
2699
2700 module_init(init_sg);
2701 module_exit(exit_sg);