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Merge tag 'irqchip-4.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm...
[mirror_ubuntu-artful-kernel.git] / drivers / scsi / sg.c
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 list_head entry; /* list entry */
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 struct mutex f_mutex; /* protect against changes in this fd */
146 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
147 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
148 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
149 struct list_head rq_list; /* head of request list */
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 force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
153 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
154 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
155 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
156 char mmap_called; /* 0 -> mmap() never called on this fd */
157 char res_in_use; /* 1 -> 'reserve' array in use */
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, blk_status_t status);
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 Sg_device *sg_get_dev(int dev);
202 static void sg_device_destroy(struct kref *kref);
203
204 #define SZ_SG_HEADER sizeof(struct sg_header)
205 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
206 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
207 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
208
209 #define sg_printk(prefix, sdp, fmt, a...) \
210 sdev_prefix_printk(prefix, (sdp)->device, \
211 (sdp)->disk->disk_name, fmt, ##a)
212
213 static int sg_allow_access(struct file *filp, unsigned char *cmd)
214 {
215 struct sg_fd *sfp = filp->private_data;
216
217 if (sfp->parentdp->device->type == TYPE_SCANNER)
218 return 0;
219
220 return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
221 }
222
223 static int
224 open_wait(Sg_device *sdp, int flags)
225 {
226 int retval = 0;
227
228 if (flags & O_EXCL) {
229 while (sdp->open_cnt > 0) {
230 mutex_unlock(&sdp->open_rel_lock);
231 retval = wait_event_interruptible(sdp->open_wait,
232 (atomic_read(&sdp->detaching) ||
233 !sdp->open_cnt));
234 mutex_lock(&sdp->open_rel_lock);
235
236 if (retval) /* -ERESTARTSYS */
237 return retval;
238 if (atomic_read(&sdp->detaching))
239 return -ENODEV;
240 }
241 } else {
242 while (sdp->exclude) {
243 mutex_unlock(&sdp->open_rel_lock);
244 retval = wait_event_interruptible(sdp->open_wait,
245 (atomic_read(&sdp->detaching) ||
246 !sdp->exclude));
247 mutex_lock(&sdp->open_rel_lock);
248
249 if (retval) /* -ERESTARTSYS */
250 return retval;
251 if (atomic_read(&sdp->detaching))
252 return -ENODEV;
253 }
254 }
255
256 return retval;
257 }
258
259 /* Returns 0 on success, else a negated errno value */
260 static int
261 sg_open(struct inode *inode, struct file *filp)
262 {
263 int dev = iminor(inode);
264 int flags = filp->f_flags;
265 struct request_queue *q;
266 Sg_device *sdp;
267 Sg_fd *sfp;
268 int retval;
269
270 nonseekable_open(inode, filp);
271 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
272 return -EPERM; /* Can't lock it with read only access */
273 sdp = sg_get_dev(dev);
274 if (IS_ERR(sdp))
275 return PTR_ERR(sdp);
276
277 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
278 "sg_open: flags=0x%x\n", flags));
279
280 /* This driver's module count bumped by fops_get in <linux/fs.h> */
281 /* Prevent the device driver from vanishing while we sleep */
282 retval = scsi_device_get(sdp->device);
283 if (retval)
284 goto sg_put;
285
286 retval = scsi_autopm_get_device(sdp->device);
287 if (retval)
288 goto sdp_put;
289
290 /* scsi_block_when_processing_errors() may block so bypass
291 * check if O_NONBLOCK. Permits SCSI commands to be issued
292 * during error recovery. Tread carefully. */
293 if (!((flags & O_NONBLOCK) ||
294 scsi_block_when_processing_errors(sdp->device))) {
295 retval = -ENXIO;
296 /* we are in error recovery for this device */
297 goto error_out;
298 }
299
300 mutex_lock(&sdp->open_rel_lock);
301 if (flags & O_NONBLOCK) {
302 if (flags & O_EXCL) {
303 if (sdp->open_cnt > 0) {
304 retval = -EBUSY;
305 goto error_mutex_locked;
306 }
307 } else {
308 if (sdp->exclude) {
309 retval = -EBUSY;
310 goto error_mutex_locked;
311 }
312 }
313 } else {
314 retval = open_wait(sdp, flags);
315 if (retval) /* -ERESTARTSYS or -ENODEV */
316 goto error_mutex_locked;
317 }
318
319 /* N.B. at this point we are holding the open_rel_lock */
320 if (flags & O_EXCL)
321 sdp->exclude = true;
322
323 if (sdp->open_cnt < 1) { /* no existing opens */
324 sdp->sgdebug = 0;
325 q = sdp->device->request_queue;
326 sdp->sg_tablesize = queue_max_segments(q);
327 }
328 sfp = sg_add_sfp(sdp);
329 if (IS_ERR(sfp)) {
330 retval = PTR_ERR(sfp);
331 goto out_undo;
332 }
333
334 filp->private_data = sfp;
335 sdp->open_cnt++;
336 mutex_unlock(&sdp->open_rel_lock);
337
338 retval = 0;
339 sg_put:
340 kref_put(&sdp->d_ref, sg_device_destroy);
341 return retval;
342
343 out_undo:
344 if (flags & O_EXCL) {
345 sdp->exclude = false; /* undo if error */
346 wake_up_interruptible(&sdp->open_wait);
347 }
348 error_mutex_locked:
349 mutex_unlock(&sdp->open_rel_lock);
350 error_out:
351 scsi_autopm_put_device(sdp->device);
352 sdp_put:
353 scsi_device_put(sdp->device);
354 goto sg_put;
355 }
356
357 /* Release resources associated with a successful sg_open()
358 * Returns 0 on success, else a negated errno value */
359 static int
360 sg_release(struct inode *inode, struct file *filp)
361 {
362 Sg_device *sdp;
363 Sg_fd *sfp;
364
365 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
366 return -ENXIO;
367 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
368
369 mutex_lock(&sdp->open_rel_lock);
370 scsi_autopm_put_device(sdp->device);
371 kref_put(&sfp->f_ref, sg_remove_sfp);
372 sdp->open_cnt--;
373
374 /* possibly many open()s waiting on exlude clearing, start many;
375 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
376 if (sdp->exclude) {
377 sdp->exclude = false;
378 wake_up_interruptible_all(&sdp->open_wait);
379 } else if (0 == sdp->open_cnt) {
380 wake_up_interruptible(&sdp->open_wait);
381 }
382 mutex_unlock(&sdp->open_rel_lock);
383 return 0;
384 }
385
386 static ssize_t
387 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
388 {
389 Sg_device *sdp;
390 Sg_fd *sfp;
391 Sg_request *srp;
392 int req_pack_id = -1;
393 sg_io_hdr_t *hp;
394 struct sg_header *old_hdr = NULL;
395 int retval = 0;
396
397 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
398 return -ENXIO;
399 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
400 "sg_read: count=%d\n", (int) count));
401
402 if (!access_ok(VERIFY_WRITE, buf, count))
403 return -EFAULT;
404 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
405 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
406 if (!old_hdr)
407 return -ENOMEM;
408 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
409 retval = -EFAULT;
410 goto free_old_hdr;
411 }
412 if (old_hdr->reply_len < 0) {
413 if (count >= SZ_SG_IO_HDR) {
414 sg_io_hdr_t *new_hdr;
415 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
416 if (!new_hdr) {
417 retval = -ENOMEM;
418 goto free_old_hdr;
419 }
420 retval =__copy_from_user
421 (new_hdr, buf, SZ_SG_IO_HDR);
422 req_pack_id = new_hdr->pack_id;
423 kfree(new_hdr);
424 if (retval) {
425 retval = -EFAULT;
426 goto free_old_hdr;
427 }
428 }
429 } else
430 req_pack_id = old_hdr->pack_id;
431 }
432 srp = sg_get_rq_mark(sfp, req_pack_id);
433 if (!srp) { /* now wait on packet to arrive */
434 if (atomic_read(&sdp->detaching)) {
435 retval = -ENODEV;
436 goto free_old_hdr;
437 }
438 if (filp->f_flags & O_NONBLOCK) {
439 retval = -EAGAIN;
440 goto free_old_hdr;
441 }
442 retval = wait_event_interruptible(sfp->read_wait,
443 (atomic_read(&sdp->detaching) ||
444 (srp = sg_get_rq_mark(sfp, req_pack_id))));
445 if (atomic_read(&sdp->detaching)) {
446 retval = -ENODEV;
447 goto free_old_hdr;
448 }
449 if (retval) {
450 /* -ERESTARTSYS as signal hit process */
451 goto free_old_hdr;
452 }
453 }
454 if (srp->header.interface_id != '\0') {
455 retval = sg_new_read(sfp, buf, count, srp);
456 goto free_old_hdr;
457 }
458
459 hp = &srp->header;
460 if (old_hdr == NULL) {
461 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
462 if (! old_hdr) {
463 retval = -ENOMEM;
464 goto free_old_hdr;
465 }
466 }
467 memset(old_hdr, 0, SZ_SG_HEADER);
468 old_hdr->reply_len = (int) hp->timeout;
469 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
470 old_hdr->pack_id = hp->pack_id;
471 old_hdr->twelve_byte =
472 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
473 old_hdr->target_status = hp->masked_status;
474 old_hdr->host_status = hp->host_status;
475 old_hdr->driver_status = hp->driver_status;
476 if ((CHECK_CONDITION & hp->masked_status) ||
477 (DRIVER_SENSE & hp->driver_status))
478 memcpy(old_hdr->sense_buffer, srp->sense_b,
479 sizeof (old_hdr->sense_buffer));
480 switch (hp->host_status) {
481 /* This setup of 'result' is for backward compatibility and is best
482 ignored by the user who should use target, host + driver status */
483 case DID_OK:
484 case DID_PASSTHROUGH:
485 case DID_SOFT_ERROR:
486 old_hdr->result = 0;
487 break;
488 case DID_NO_CONNECT:
489 case DID_BUS_BUSY:
490 case DID_TIME_OUT:
491 old_hdr->result = EBUSY;
492 break;
493 case DID_BAD_TARGET:
494 case DID_ABORT:
495 case DID_PARITY:
496 case DID_RESET:
497 case DID_BAD_INTR:
498 old_hdr->result = EIO;
499 break;
500 case DID_ERROR:
501 old_hdr->result = (srp->sense_b[0] == 0 &&
502 hp->masked_status == GOOD) ? 0 : EIO;
503 break;
504 default:
505 old_hdr->result = EIO;
506 break;
507 }
508
509 /* Now copy the result back to the user buffer. */
510 if (count >= SZ_SG_HEADER) {
511 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
512 retval = -EFAULT;
513 goto free_old_hdr;
514 }
515 buf += SZ_SG_HEADER;
516 if (count > old_hdr->reply_len)
517 count = old_hdr->reply_len;
518 if (count > SZ_SG_HEADER) {
519 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
520 retval = -EFAULT;
521 goto free_old_hdr;
522 }
523 }
524 } else
525 count = (old_hdr->result == 0) ? 0 : -EIO;
526 sg_finish_rem_req(srp);
527 sg_remove_request(sfp, 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 sg_remove_request(sfp, srp);
569 return err ? : err2 ? : count;
570 }
571
572 static ssize_t
573 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
574 {
575 int mxsize, cmd_size, k;
576 int input_size, blocking;
577 unsigned char opcode;
578 Sg_device *sdp;
579 Sg_fd *sfp;
580 Sg_request *srp;
581 struct sg_header old_hdr;
582 sg_io_hdr_t *hp;
583 unsigned char cmnd[SG_MAX_CDB_SIZE];
584
585 if (unlikely(uaccess_kernel()))
586 return -EINVAL;
587
588 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
589 return -ENXIO;
590 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
591 "sg_write: count=%d\n", (int) count));
592 if (atomic_read(&sdp->detaching))
593 return -ENODEV;
594 if (!((filp->f_flags & O_NONBLOCK) ||
595 scsi_block_when_processing_errors(sdp->device)))
596 return -ENXIO;
597
598 if (!access_ok(VERIFY_READ, buf, count))
599 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
600 if (count < SZ_SG_HEADER)
601 return -EIO;
602 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
603 return -EFAULT;
604 blocking = !(filp->f_flags & O_NONBLOCK);
605 if (old_hdr.reply_len < 0)
606 return sg_new_write(sfp, filp, buf, count,
607 blocking, 0, 0, NULL);
608 if (count < (SZ_SG_HEADER + 6))
609 return -EIO; /* The minimum scsi command length is 6 bytes. */
610
611 if (!(srp = sg_add_request(sfp))) {
612 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
613 "sg_write: queue full\n"));
614 return -EDOM;
615 }
616 buf += SZ_SG_HEADER;
617 __get_user(opcode, buf);
618 mutex_lock(&sfp->f_mutex);
619 if (sfp->next_cmd_len > 0) {
620 cmd_size = sfp->next_cmd_len;
621 sfp->next_cmd_len = 0; /* reset so only this write() effected */
622 } else {
623 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
624 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
625 cmd_size = 12;
626 }
627 mutex_unlock(&sfp->f_mutex);
628 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
629 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
630 /* Determine buffer size. */
631 input_size = count - cmd_size;
632 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
633 mxsize -= SZ_SG_HEADER;
634 input_size -= SZ_SG_HEADER;
635 if (input_size < 0) {
636 sg_remove_request(sfp, srp);
637 return -EIO; /* User did not pass enough bytes for this command. */
638 }
639 hp = &srp->header;
640 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
641 hp->cmd_len = (unsigned char) cmd_size;
642 hp->iovec_count = 0;
643 hp->mx_sb_len = 0;
644 if (input_size > 0)
645 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
646 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
647 else
648 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
649 hp->dxfer_len = mxsize;
650 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
651 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
652 hp->dxferp = (char __user *)buf + cmd_size;
653 else
654 hp->dxferp = NULL;
655 hp->sbp = NULL;
656 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
657 hp->flags = input_size; /* structure abuse ... */
658 hp->pack_id = old_hdr.pack_id;
659 hp->usr_ptr = NULL;
660 if (__copy_from_user(cmnd, buf, cmd_size))
661 return -EFAULT;
662 /*
663 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
664 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
665 * is a non-zero input_size, so emit a warning.
666 */
667 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
668 printk_ratelimited(KERN_WARNING
669 "sg_write: data in/out %d/%d bytes "
670 "for SCSI command 0x%x-- guessing "
671 "data in;\n program %s not setting "
672 "count and/or reply_len properly\n",
673 old_hdr.reply_len - (int)SZ_SG_HEADER,
674 input_size, (unsigned int) cmnd[0],
675 current->comm);
676 }
677 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
678 return (k < 0) ? k : count;
679 }
680
681 static ssize_t
682 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
683 size_t count, int blocking, int read_only, int sg_io_owned,
684 Sg_request **o_srp)
685 {
686 int k;
687 Sg_request *srp;
688 sg_io_hdr_t *hp;
689 unsigned char cmnd[SG_MAX_CDB_SIZE];
690 int timeout;
691 unsigned long ul_timeout;
692
693 if (count < SZ_SG_IO_HDR)
694 return -EINVAL;
695 if (!access_ok(VERIFY_READ, buf, count))
696 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
697
698 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
699 if (!(srp = sg_add_request(sfp))) {
700 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
701 "sg_new_write: queue full\n"));
702 return -EDOM;
703 }
704 srp->sg_io_owned = sg_io_owned;
705 hp = &srp->header;
706 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
707 sg_remove_request(sfp, srp);
708 return -EFAULT;
709 }
710 if (hp->interface_id != 'S') {
711 sg_remove_request(sfp, srp);
712 return -ENOSYS;
713 }
714 if (hp->flags & SG_FLAG_MMAP_IO) {
715 if (hp->dxfer_len > sfp->reserve.bufflen) {
716 sg_remove_request(sfp, srp);
717 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
718 }
719 if (hp->flags & SG_FLAG_DIRECT_IO) {
720 sg_remove_request(sfp, srp);
721 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
722 }
723 if (sfp->res_in_use) {
724 sg_remove_request(sfp, srp);
725 return -EBUSY; /* reserve buffer already being used */
726 }
727 }
728 ul_timeout = msecs_to_jiffies(srp->header.timeout);
729 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
730 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
731 sg_remove_request(sfp, srp);
732 return -EMSGSIZE;
733 }
734 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
735 sg_remove_request(sfp, srp);
736 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
737 }
738 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
739 sg_remove_request(sfp, srp);
740 return -EFAULT;
741 }
742 if (read_only && sg_allow_access(file, cmnd)) {
743 sg_remove_request(sfp, srp);
744 return -EPERM;
745 }
746 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
747 if (k < 0)
748 return k;
749 if (o_srp)
750 *o_srp = srp;
751 return count;
752 }
753
754 static bool sg_is_valid_dxfer(sg_io_hdr_t *hp)
755 {
756 switch (hp->dxfer_direction) {
757 case SG_DXFER_NONE:
758 if (hp->dxferp || hp->dxfer_len > 0)
759 return false;
760 return true;
761 case SG_DXFER_FROM_DEV:
762 /*
763 * for SG_DXFER_FROM_DEV we always set dxfer_len to > 0. dxferp
764 * can either be NULL or != NULL so there's no point in checking
765 * it either. So just return true.
766 */
767 return true;
768 case SG_DXFER_TO_DEV:
769 case SG_DXFER_TO_FROM_DEV:
770 if (!hp->dxferp || hp->dxfer_len == 0)
771 return false;
772 return true;
773 case SG_DXFER_UNKNOWN:
774 if ((!hp->dxferp && hp->dxfer_len) ||
775 (hp->dxferp && hp->dxfer_len == 0))
776 return false;
777 return true;
778 default:
779 return false;
780 }
781 }
782
783 static int
784 sg_common_write(Sg_fd * sfp, Sg_request * srp,
785 unsigned char *cmnd, int timeout, int blocking)
786 {
787 int k, at_head;
788 Sg_device *sdp = sfp->parentdp;
789 sg_io_hdr_t *hp = &srp->header;
790
791 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
792 hp->status = 0;
793 hp->masked_status = 0;
794 hp->msg_status = 0;
795 hp->info = 0;
796 hp->host_status = 0;
797 hp->driver_status = 0;
798 hp->resid = 0;
799 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
800 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
801 (int) cmnd[0], (int) hp->cmd_len));
802
803 if (!sg_is_valid_dxfer(hp))
804 return -EINVAL;
805
806 k = sg_start_req(srp, cmnd);
807 if (k) {
808 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
809 "sg_common_write: start_req err=%d\n", k));
810 sg_finish_rem_req(srp);
811 sg_remove_request(sfp, srp);
812 return k; /* probably out of space --> ENOMEM */
813 }
814 if (atomic_read(&sdp->detaching)) {
815 if (srp->bio) {
816 scsi_req_free_cmd(scsi_req(srp->rq));
817 blk_end_request_all(srp->rq, BLK_STS_IOERR);
818 srp->rq = NULL;
819 }
820
821 sg_finish_rem_req(srp);
822 sg_remove_request(sfp, srp);
823 return -ENODEV;
824 }
825
826 hp->duration = jiffies_to_msecs(jiffies);
827 if (hp->interface_id != '\0' && /* v3 (or later) interface */
828 (SG_FLAG_Q_AT_TAIL & hp->flags))
829 at_head = 0;
830 else
831 at_head = 1;
832
833 srp->rq->timeout = timeout;
834 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
835 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
836 srp->rq, at_head, sg_rq_end_io);
837 return 0;
838 }
839
840 static int srp_done(Sg_fd *sfp, Sg_request *srp)
841 {
842 unsigned long flags;
843 int ret;
844
845 read_lock_irqsave(&sfp->rq_list_lock, flags);
846 ret = srp->done;
847 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
848 return ret;
849 }
850
851 static int max_sectors_bytes(struct request_queue *q)
852 {
853 unsigned int max_sectors = queue_max_sectors(q);
854
855 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
856
857 return max_sectors << 9;
858 }
859
860 static long
861 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
862 {
863 void __user *p = (void __user *)arg;
864 int __user *ip = p;
865 int result, val, read_only;
866 Sg_device *sdp;
867 Sg_fd *sfp;
868 Sg_request *srp;
869 unsigned long iflags;
870
871 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
872 return -ENXIO;
873
874 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
875 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
876 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
877
878 switch (cmd_in) {
879 case SG_IO:
880 if (atomic_read(&sdp->detaching))
881 return -ENODEV;
882 if (!scsi_block_when_processing_errors(sdp->device))
883 return -ENXIO;
884 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
885 return -EFAULT;
886 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
887 1, read_only, 1, &srp);
888 if (result < 0)
889 return result;
890 result = wait_event_interruptible(sfp->read_wait,
891 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
892 if (atomic_read(&sdp->detaching))
893 return -ENODEV;
894 write_lock_irq(&sfp->rq_list_lock);
895 if (srp->done) {
896 srp->done = 2;
897 write_unlock_irq(&sfp->rq_list_lock);
898 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
899 return (result < 0) ? result : 0;
900 }
901 srp->orphan = 1;
902 write_unlock_irq(&sfp->rq_list_lock);
903 return result; /* -ERESTARTSYS because signal hit process */
904 case SG_SET_TIMEOUT:
905 result = get_user(val, ip);
906 if (result)
907 return result;
908 if (val < 0)
909 return -EIO;
910 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
911 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
912 INT_MAX);
913 sfp->timeout_user = val;
914 sfp->timeout = mult_frac(val, HZ, USER_HZ);
915
916 return 0;
917 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
918 /* strange ..., for backward compatibility */
919 return sfp->timeout_user;
920 case SG_SET_FORCE_LOW_DMA:
921 /*
922 * N.B. This ioctl never worked properly, but failed to
923 * return an error value. So returning '0' to keep compability
924 * with legacy applications.
925 */
926 return 0;
927 case SG_GET_LOW_DMA:
928 return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
929 case SG_GET_SCSI_ID:
930 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
931 return -EFAULT;
932 else {
933 sg_scsi_id_t __user *sg_idp = p;
934
935 if (atomic_read(&sdp->detaching))
936 return -ENODEV;
937 __put_user((int) sdp->device->host->host_no,
938 &sg_idp->host_no);
939 __put_user((int) sdp->device->channel,
940 &sg_idp->channel);
941 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
942 __put_user((int) sdp->device->lun, &sg_idp->lun);
943 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
944 __put_user((short) sdp->device->host->cmd_per_lun,
945 &sg_idp->h_cmd_per_lun);
946 __put_user((short) sdp->device->queue_depth,
947 &sg_idp->d_queue_depth);
948 __put_user(0, &sg_idp->unused[0]);
949 __put_user(0, &sg_idp->unused[1]);
950 return 0;
951 }
952 case SG_SET_FORCE_PACK_ID:
953 result = get_user(val, ip);
954 if (result)
955 return result;
956 sfp->force_packid = val ? 1 : 0;
957 return 0;
958 case SG_GET_PACK_ID:
959 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
960 return -EFAULT;
961 read_lock_irqsave(&sfp->rq_list_lock, iflags);
962 list_for_each_entry(srp, &sfp->rq_list, entry) {
963 if ((1 == srp->done) && (!srp->sg_io_owned)) {
964 read_unlock_irqrestore(&sfp->rq_list_lock,
965 iflags);
966 __put_user(srp->header.pack_id, ip);
967 return 0;
968 }
969 }
970 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
971 __put_user(-1, ip);
972 return 0;
973 case SG_GET_NUM_WAITING:
974 read_lock_irqsave(&sfp->rq_list_lock, iflags);
975 val = 0;
976 list_for_each_entry(srp, &sfp->rq_list, entry) {
977 if ((1 == srp->done) && (!srp->sg_io_owned))
978 ++val;
979 }
980 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
981 return put_user(val, ip);
982 case SG_GET_SG_TABLESIZE:
983 return put_user(sdp->sg_tablesize, ip);
984 case SG_SET_RESERVED_SIZE:
985 result = get_user(val, ip);
986 if (result)
987 return result;
988 if (val < 0)
989 return -EINVAL;
990 val = min_t(int, val,
991 max_sectors_bytes(sdp->device->request_queue));
992 mutex_lock(&sfp->f_mutex);
993 if (val != sfp->reserve.bufflen) {
994 if (sfp->mmap_called ||
995 sfp->res_in_use) {
996 mutex_unlock(&sfp->f_mutex);
997 return -EBUSY;
998 }
999
1000 sg_remove_scat(sfp, &sfp->reserve);
1001 sg_build_reserve(sfp, val);
1002 }
1003 mutex_unlock(&sfp->f_mutex);
1004 return 0;
1005 case SG_GET_RESERVED_SIZE:
1006 val = min_t(int, sfp->reserve.bufflen,
1007 max_sectors_bytes(sdp->device->request_queue));
1008 return put_user(val, ip);
1009 case SG_SET_COMMAND_Q:
1010 result = get_user(val, ip);
1011 if (result)
1012 return result;
1013 sfp->cmd_q = val ? 1 : 0;
1014 return 0;
1015 case SG_GET_COMMAND_Q:
1016 return put_user((int) sfp->cmd_q, ip);
1017 case SG_SET_KEEP_ORPHAN:
1018 result = get_user(val, ip);
1019 if (result)
1020 return result;
1021 sfp->keep_orphan = val;
1022 return 0;
1023 case SG_GET_KEEP_ORPHAN:
1024 return put_user((int) sfp->keep_orphan, ip);
1025 case SG_NEXT_CMD_LEN:
1026 result = get_user(val, ip);
1027 if (result)
1028 return result;
1029 if (val > SG_MAX_CDB_SIZE)
1030 return -ENOMEM;
1031 sfp->next_cmd_len = (val > 0) ? val : 0;
1032 return 0;
1033 case SG_GET_VERSION_NUM:
1034 return put_user(sg_version_num, ip);
1035 case SG_GET_ACCESS_COUNT:
1036 /* faked - we don't have a real access count anymore */
1037 val = (sdp->device ? 1 : 0);
1038 return put_user(val, ip);
1039 case SG_GET_REQUEST_TABLE:
1040 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
1041 return -EFAULT;
1042 else {
1043 sg_req_info_t *rinfo;
1044 unsigned int ms;
1045
1046 rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
1047 GFP_KERNEL);
1048 if (!rinfo)
1049 return -ENOMEM;
1050 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1051 val = 0;
1052 list_for_each_entry(srp, &sfp->rq_list, entry) {
1053 if (val > SG_MAX_QUEUE)
1054 break;
1055 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
1056 rinfo[val].req_state = srp->done + 1;
1057 rinfo[val].problem =
1058 srp->header.masked_status &
1059 srp->header.host_status &
1060 srp->header.driver_status;
1061 if (srp->done)
1062 rinfo[val].duration =
1063 srp->header.duration;
1064 else {
1065 ms = jiffies_to_msecs(jiffies);
1066 rinfo[val].duration =
1067 (ms > srp->header.duration) ?
1068 (ms - srp->header.duration) : 0;
1069 }
1070 rinfo[val].orphan = srp->orphan;
1071 rinfo[val].sg_io_owned = srp->sg_io_owned;
1072 rinfo[val].pack_id = srp->header.pack_id;
1073 rinfo[val].usr_ptr = srp->header.usr_ptr;
1074 val++;
1075 }
1076 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1077 result = __copy_to_user(p, rinfo,
1078 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1079 result = result ? -EFAULT : 0;
1080 kfree(rinfo);
1081 return result;
1082 }
1083 case SG_EMULATED_HOST:
1084 if (atomic_read(&sdp->detaching))
1085 return -ENODEV;
1086 return put_user(sdp->device->host->hostt->emulated, ip);
1087 case SCSI_IOCTL_SEND_COMMAND:
1088 if (atomic_read(&sdp->detaching))
1089 return -ENODEV;
1090 if (read_only) {
1091 unsigned char opcode = WRITE_6;
1092 Scsi_Ioctl_Command __user *siocp = p;
1093
1094 if (copy_from_user(&opcode, siocp->data, 1))
1095 return -EFAULT;
1096 if (sg_allow_access(filp, &opcode))
1097 return -EPERM;
1098 }
1099 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1100 case SG_SET_DEBUG:
1101 result = get_user(val, ip);
1102 if (result)
1103 return result;
1104 sdp->sgdebug = (char) val;
1105 return 0;
1106 case BLKSECTGET:
1107 return put_user(max_sectors_bytes(sdp->device->request_queue),
1108 ip);
1109 case BLKTRACESETUP:
1110 return blk_trace_setup(sdp->device->request_queue,
1111 sdp->disk->disk_name,
1112 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1113 NULL,
1114 (char *)arg);
1115 case BLKTRACESTART:
1116 return blk_trace_startstop(sdp->device->request_queue, 1);
1117 case BLKTRACESTOP:
1118 return blk_trace_startstop(sdp->device->request_queue, 0);
1119 case BLKTRACETEARDOWN:
1120 return blk_trace_remove(sdp->device->request_queue);
1121 case SCSI_IOCTL_GET_IDLUN:
1122 case SCSI_IOCTL_GET_BUS_NUMBER:
1123 case SCSI_IOCTL_PROBE_HOST:
1124 case SG_GET_TRANSFORM:
1125 case SG_SCSI_RESET:
1126 if (atomic_read(&sdp->detaching))
1127 return -ENODEV;
1128 break;
1129 default:
1130 if (read_only)
1131 return -EPERM; /* don't know so take safe approach */
1132 break;
1133 }
1134
1135 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1136 cmd_in, filp->f_flags & O_NDELAY);
1137 if (result)
1138 return result;
1139 return scsi_ioctl(sdp->device, cmd_in, p);
1140 }
1141
1142 #ifdef CONFIG_COMPAT
1143 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1144 {
1145 Sg_device *sdp;
1146 Sg_fd *sfp;
1147 struct scsi_device *sdev;
1148
1149 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1150 return -ENXIO;
1151
1152 sdev = sdp->device;
1153 if (sdev->host->hostt->compat_ioctl) {
1154 int ret;
1155
1156 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1157
1158 return ret;
1159 }
1160
1161 return -ENOIOCTLCMD;
1162 }
1163 #endif
1164
1165 static unsigned int
1166 sg_poll(struct file *filp, poll_table * wait)
1167 {
1168 unsigned int res = 0;
1169 Sg_device *sdp;
1170 Sg_fd *sfp;
1171 Sg_request *srp;
1172 int count = 0;
1173 unsigned long iflags;
1174
1175 sfp = filp->private_data;
1176 if (!sfp)
1177 return POLLERR;
1178 sdp = sfp->parentdp;
1179 if (!sdp)
1180 return POLLERR;
1181 poll_wait(filp, &sfp->read_wait, wait);
1182 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1183 list_for_each_entry(srp, &sfp->rq_list, entry) {
1184 /* if any read waiting, flag it */
1185 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1186 res = POLLIN | POLLRDNORM;
1187 ++count;
1188 }
1189 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1190
1191 if (atomic_read(&sdp->detaching))
1192 res |= POLLHUP;
1193 else if (!sfp->cmd_q) {
1194 if (0 == count)
1195 res |= POLLOUT | POLLWRNORM;
1196 } else if (count < SG_MAX_QUEUE)
1197 res |= POLLOUT | POLLWRNORM;
1198 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1199 "sg_poll: res=0x%x\n", (int) res));
1200 return res;
1201 }
1202
1203 static int
1204 sg_fasync(int fd, struct file *filp, int mode)
1205 {
1206 Sg_device *sdp;
1207 Sg_fd *sfp;
1208
1209 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1210 return -ENXIO;
1211 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1212 "sg_fasync: mode=%d\n", mode));
1213
1214 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1215 }
1216
1217 static int
1218 sg_vma_fault(struct vm_fault *vmf)
1219 {
1220 struct vm_area_struct *vma = vmf->vma;
1221 Sg_fd *sfp;
1222 unsigned long offset, len, sa;
1223 Sg_scatter_hold *rsv_schp;
1224 int k, length;
1225
1226 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1227 return VM_FAULT_SIGBUS;
1228 rsv_schp = &sfp->reserve;
1229 offset = vmf->pgoff << PAGE_SHIFT;
1230 if (offset >= rsv_schp->bufflen)
1231 return VM_FAULT_SIGBUS;
1232 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1233 "sg_vma_fault: offset=%lu, scatg=%d\n",
1234 offset, rsv_schp->k_use_sg));
1235 sa = vma->vm_start;
1236 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1237 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1238 len = vma->vm_end - sa;
1239 len = (len < length) ? len : length;
1240 if (offset < len) {
1241 struct page *page = nth_page(rsv_schp->pages[k],
1242 offset >> PAGE_SHIFT);
1243 get_page(page); /* increment page count */
1244 vmf->page = page;
1245 return 0; /* success */
1246 }
1247 sa += len;
1248 offset -= len;
1249 }
1250
1251 return VM_FAULT_SIGBUS;
1252 }
1253
1254 static const struct vm_operations_struct sg_mmap_vm_ops = {
1255 .fault = sg_vma_fault,
1256 };
1257
1258 static int
1259 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1260 {
1261 Sg_fd *sfp;
1262 unsigned long req_sz, len, sa;
1263 Sg_scatter_hold *rsv_schp;
1264 int k, length;
1265
1266 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1267 return -ENXIO;
1268 req_sz = vma->vm_end - vma->vm_start;
1269 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1270 "sg_mmap starting, vm_start=%p, len=%d\n",
1271 (void *) vma->vm_start, (int) req_sz));
1272 if (vma->vm_pgoff)
1273 return -EINVAL; /* want no offset */
1274 rsv_schp = &sfp->reserve;
1275 if (req_sz > rsv_schp->bufflen)
1276 return -ENOMEM; /* cannot map more than reserved buffer */
1277
1278 sa = vma->vm_start;
1279 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1280 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1281 len = vma->vm_end - sa;
1282 len = (len < length) ? len : length;
1283 sa += len;
1284 }
1285
1286 sfp->mmap_called = 1;
1287 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1288 vma->vm_private_data = sfp;
1289 vma->vm_ops = &sg_mmap_vm_ops;
1290 return 0;
1291 }
1292
1293 static void
1294 sg_rq_end_io_usercontext(struct work_struct *work)
1295 {
1296 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1297 struct sg_fd *sfp = srp->parentfp;
1298
1299 sg_finish_rem_req(srp);
1300 sg_remove_request(sfp, srp);
1301 kref_put(&sfp->f_ref, sg_remove_sfp);
1302 }
1303
1304 /*
1305 * This function is a "bottom half" handler that is called by the mid
1306 * level when a command is completed (or has failed).
1307 */
1308 static void
1309 sg_rq_end_io(struct request *rq, blk_status_t status)
1310 {
1311 struct sg_request *srp = rq->end_io_data;
1312 struct scsi_request *req = scsi_req(rq);
1313 Sg_device *sdp;
1314 Sg_fd *sfp;
1315 unsigned long iflags;
1316 unsigned int ms;
1317 char *sense;
1318 int result, resid, done = 1;
1319
1320 if (WARN_ON(srp->done != 0))
1321 return;
1322
1323 sfp = srp->parentfp;
1324 if (WARN_ON(sfp == NULL))
1325 return;
1326
1327 sdp = sfp->parentdp;
1328 if (unlikely(atomic_read(&sdp->detaching)))
1329 pr_info("%s: device detaching\n", __func__);
1330
1331 sense = req->sense;
1332 result = req->result;
1333 resid = req->resid_len;
1334
1335 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1336 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1337 srp->header.pack_id, result));
1338 srp->header.resid = resid;
1339 ms = jiffies_to_msecs(jiffies);
1340 srp->header.duration = (ms > srp->header.duration) ?
1341 (ms - srp->header.duration) : 0;
1342 if (0 != result) {
1343 struct scsi_sense_hdr sshdr;
1344
1345 srp->header.status = 0xff & result;
1346 srp->header.masked_status = status_byte(result);
1347 srp->header.msg_status = msg_byte(result);
1348 srp->header.host_status = host_byte(result);
1349 srp->header.driver_status = driver_byte(result);
1350 if ((sdp->sgdebug > 0) &&
1351 ((CHECK_CONDITION == srp->header.masked_status) ||
1352 (COMMAND_TERMINATED == srp->header.masked_status)))
1353 __scsi_print_sense(sdp->device, __func__, sense,
1354 SCSI_SENSE_BUFFERSIZE);
1355
1356 /* Following if statement is a patch supplied by Eric Youngdale */
1357 if (driver_byte(result) != 0
1358 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1359 && !scsi_sense_is_deferred(&sshdr)
1360 && sshdr.sense_key == UNIT_ATTENTION
1361 && sdp->device->removable) {
1362 /* Detected possible disc change. Set the bit - this */
1363 /* may be used if there are filesystems using this device */
1364 sdp->device->changed = 1;
1365 }
1366 }
1367
1368 if (req->sense_len)
1369 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1370
1371 /* Rely on write phase to clean out srp status values, so no "else" */
1372
1373 /*
1374 * Free the request as soon as it is complete so that its resources
1375 * can be reused without waiting for userspace to read() the
1376 * result. But keep the associated bio (if any) around until
1377 * blk_rq_unmap_user() can be called from user context.
1378 */
1379 srp->rq = NULL;
1380 scsi_req_free_cmd(scsi_req(rq));
1381 __blk_put_request(rq->q, rq);
1382
1383 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1384 if (unlikely(srp->orphan)) {
1385 if (sfp->keep_orphan)
1386 srp->sg_io_owned = 0;
1387 else
1388 done = 0;
1389 }
1390 srp->done = done;
1391 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1392
1393 if (likely(done)) {
1394 /* Now wake up any sg_read() that is waiting for this
1395 * packet.
1396 */
1397 wake_up_interruptible(&sfp->read_wait);
1398 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1399 kref_put(&sfp->f_ref, sg_remove_sfp);
1400 } else {
1401 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1402 schedule_work(&srp->ew.work);
1403 }
1404 }
1405
1406 static const struct file_operations sg_fops = {
1407 .owner = THIS_MODULE,
1408 .read = sg_read,
1409 .write = sg_write,
1410 .poll = sg_poll,
1411 .unlocked_ioctl = sg_ioctl,
1412 #ifdef CONFIG_COMPAT
1413 .compat_ioctl = sg_compat_ioctl,
1414 #endif
1415 .open = sg_open,
1416 .mmap = sg_mmap,
1417 .release = sg_release,
1418 .fasync = sg_fasync,
1419 .llseek = no_llseek,
1420 };
1421
1422 static struct class *sg_sysfs_class;
1423
1424 static int sg_sysfs_valid = 0;
1425
1426 static Sg_device *
1427 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1428 {
1429 struct request_queue *q = scsidp->request_queue;
1430 Sg_device *sdp;
1431 unsigned long iflags;
1432 int error;
1433 u32 k;
1434
1435 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1436 if (!sdp) {
1437 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1438 "failure\n", __func__);
1439 return ERR_PTR(-ENOMEM);
1440 }
1441
1442 idr_preload(GFP_KERNEL);
1443 write_lock_irqsave(&sg_index_lock, iflags);
1444
1445 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1446 if (error < 0) {
1447 if (error == -ENOSPC) {
1448 sdev_printk(KERN_WARNING, scsidp,
1449 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1450 scsidp->type, SG_MAX_DEVS - 1);
1451 error = -ENODEV;
1452 } else {
1453 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1454 "allocation Sg_device failure: %d\n",
1455 __func__, error);
1456 }
1457 goto out_unlock;
1458 }
1459 k = error;
1460
1461 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1462 "sg_alloc: dev=%d \n", k));
1463 sprintf(disk->disk_name, "sg%d", k);
1464 disk->first_minor = k;
1465 sdp->disk = disk;
1466 sdp->device = scsidp;
1467 mutex_init(&sdp->open_rel_lock);
1468 INIT_LIST_HEAD(&sdp->sfds);
1469 init_waitqueue_head(&sdp->open_wait);
1470 atomic_set(&sdp->detaching, 0);
1471 rwlock_init(&sdp->sfd_lock);
1472 sdp->sg_tablesize = queue_max_segments(q);
1473 sdp->index = k;
1474 kref_init(&sdp->d_ref);
1475 error = 0;
1476
1477 out_unlock:
1478 write_unlock_irqrestore(&sg_index_lock, iflags);
1479 idr_preload_end();
1480
1481 if (error) {
1482 kfree(sdp);
1483 return ERR_PTR(error);
1484 }
1485 return sdp;
1486 }
1487
1488 static int
1489 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1490 {
1491 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1492 struct gendisk *disk;
1493 Sg_device *sdp = NULL;
1494 struct cdev * cdev = NULL;
1495 int error;
1496 unsigned long iflags;
1497
1498 disk = alloc_disk(1);
1499 if (!disk) {
1500 pr_warn("%s: alloc_disk failed\n", __func__);
1501 return -ENOMEM;
1502 }
1503 disk->major = SCSI_GENERIC_MAJOR;
1504
1505 error = -ENOMEM;
1506 cdev = cdev_alloc();
1507 if (!cdev) {
1508 pr_warn("%s: cdev_alloc failed\n", __func__);
1509 goto out;
1510 }
1511 cdev->owner = THIS_MODULE;
1512 cdev->ops = &sg_fops;
1513
1514 sdp = sg_alloc(disk, scsidp);
1515 if (IS_ERR(sdp)) {
1516 pr_warn("%s: sg_alloc failed\n", __func__);
1517 error = PTR_ERR(sdp);
1518 goto out;
1519 }
1520
1521 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1522 if (error)
1523 goto cdev_add_err;
1524
1525 sdp->cdev = cdev;
1526 if (sg_sysfs_valid) {
1527 struct device *sg_class_member;
1528
1529 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1530 MKDEV(SCSI_GENERIC_MAJOR,
1531 sdp->index),
1532 sdp, "%s", disk->disk_name);
1533 if (IS_ERR(sg_class_member)) {
1534 pr_err("%s: device_create failed\n", __func__);
1535 error = PTR_ERR(sg_class_member);
1536 goto cdev_add_err;
1537 }
1538 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1539 &sg_class_member->kobj, "generic");
1540 if (error)
1541 pr_err("%s: unable to make symlink 'generic' back "
1542 "to sg%d\n", __func__, sdp->index);
1543 } else
1544 pr_warn("%s: sg_sys Invalid\n", __func__);
1545
1546 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1547 "type %d\n", sdp->index, scsidp->type);
1548
1549 dev_set_drvdata(cl_dev, sdp);
1550
1551 return 0;
1552
1553 cdev_add_err:
1554 write_lock_irqsave(&sg_index_lock, iflags);
1555 idr_remove(&sg_index_idr, sdp->index);
1556 write_unlock_irqrestore(&sg_index_lock, iflags);
1557 kfree(sdp);
1558
1559 out:
1560 put_disk(disk);
1561 if (cdev)
1562 cdev_del(cdev);
1563 return error;
1564 }
1565
1566 static void
1567 sg_device_destroy(struct kref *kref)
1568 {
1569 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1570 unsigned long flags;
1571
1572 /* CAUTION! Note that the device can still be found via idr_find()
1573 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1574 * any other cleanup.
1575 */
1576
1577 write_lock_irqsave(&sg_index_lock, flags);
1578 idr_remove(&sg_index_idr, sdp->index);
1579 write_unlock_irqrestore(&sg_index_lock, flags);
1580
1581 SCSI_LOG_TIMEOUT(3,
1582 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1583
1584 put_disk(sdp->disk);
1585 kfree(sdp);
1586 }
1587
1588 static void
1589 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1590 {
1591 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1592 Sg_device *sdp = dev_get_drvdata(cl_dev);
1593 unsigned long iflags;
1594 Sg_fd *sfp;
1595 int val;
1596
1597 if (!sdp)
1598 return;
1599 /* want sdp->detaching non-zero as soon as possible */
1600 val = atomic_inc_return(&sdp->detaching);
1601 if (val > 1)
1602 return; /* only want to do following once per device */
1603
1604 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1605 "%s\n", __func__));
1606
1607 read_lock_irqsave(&sdp->sfd_lock, iflags);
1608 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1609 wake_up_interruptible_all(&sfp->read_wait);
1610 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1611 }
1612 wake_up_interruptible_all(&sdp->open_wait);
1613 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1614
1615 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1616 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1617 cdev_del(sdp->cdev);
1618 sdp->cdev = NULL;
1619
1620 kref_put(&sdp->d_ref, sg_device_destroy);
1621 }
1622
1623 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1624 module_param_named(def_reserved_size, def_reserved_size, int,
1625 S_IRUGO | S_IWUSR);
1626 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1627
1628 MODULE_AUTHOR("Douglas Gilbert");
1629 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1630 MODULE_LICENSE("GPL");
1631 MODULE_VERSION(SG_VERSION_STR);
1632 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1633
1634 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1635 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1636 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1637 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1638
1639 static int __init
1640 init_sg(void)
1641 {
1642 int rc;
1643
1644 if (scatter_elem_sz < PAGE_SIZE) {
1645 scatter_elem_sz = PAGE_SIZE;
1646 scatter_elem_sz_prev = scatter_elem_sz;
1647 }
1648 if (def_reserved_size >= 0)
1649 sg_big_buff = def_reserved_size;
1650 else
1651 def_reserved_size = sg_big_buff;
1652
1653 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1654 SG_MAX_DEVS, "sg");
1655 if (rc)
1656 return rc;
1657 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1658 if ( IS_ERR(sg_sysfs_class) ) {
1659 rc = PTR_ERR(sg_sysfs_class);
1660 goto err_out;
1661 }
1662 sg_sysfs_valid = 1;
1663 rc = scsi_register_interface(&sg_interface);
1664 if (0 == rc) {
1665 #ifdef CONFIG_SCSI_PROC_FS
1666 sg_proc_init();
1667 #endif /* CONFIG_SCSI_PROC_FS */
1668 return 0;
1669 }
1670 class_destroy(sg_sysfs_class);
1671 err_out:
1672 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1673 return rc;
1674 }
1675
1676 static void __exit
1677 exit_sg(void)
1678 {
1679 #ifdef CONFIG_SCSI_PROC_FS
1680 sg_proc_cleanup();
1681 #endif /* CONFIG_SCSI_PROC_FS */
1682 scsi_unregister_interface(&sg_interface);
1683 class_destroy(sg_sysfs_class);
1684 sg_sysfs_valid = 0;
1685 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1686 SG_MAX_DEVS);
1687 idr_destroy(&sg_index_idr);
1688 }
1689
1690 static int
1691 sg_start_req(Sg_request *srp, unsigned char *cmd)
1692 {
1693 int res;
1694 struct request *rq;
1695 struct scsi_request *req;
1696 Sg_fd *sfp = srp->parentfp;
1697 sg_io_hdr_t *hp = &srp->header;
1698 int dxfer_len = (int) hp->dxfer_len;
1699 int dxfer_dir = hp->dxfer_direction;
1700 unsigned int iov_count = hp->iovec_count;
1701 Sg_scatter_hold *req_schp = &srp->data;
1702 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1703 struct request_queue *q = sfp->parentdp->device->request_queue;
1704 struct rq_map_data *md, map_data;
1705 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1706 unsigned char *long_cmdp = NULL;
1707
1708 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1709 "sg_start_req: dxfer_len=%d\n",
1710 dxfer_len));
1711
1712 if (hp->cmd_len > BLK_MAX_CDB) {
1713 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1714 if (!long_cmdp)
1715 return -ENOMEM;
1716 }
1717
1718 /*
1719 * NOTE
1720 *
1721 * With scsi-mq enabled, there are a fixed number of preallocated
1722 * requests equal in number to shost->can_queue. If all of the
1723 * preallocated requests are already in use, then using GFP_ATOMIC with
1724 * blk_get_request() will return -EWOULDBLOCK, whereas using GFP_KERNEL
1725 * will cause blk_get_request() to sleep until an active command
1726 * completes, freeing up a request. Neither option is ideal, but
1727 * GFP_KERNEL is the better choice to prevent userspace from getting an
1728 * unexpected EWOULDBLOCK.
1729 *
1730 * With scsi-mq disabled, blk_get_request() with GFP_KERNEL usually
1731 * does not sleep except under memory pressure.
1732 */
1733 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1734 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, GFP_KERNEL);
1735 if (IS_ERR(rq)) {
1736 kfree(long_cmdp);
1737 return PTR_ERR(rq);
1738 }
1739 req = scsi_req(rq);
1740
1741 if (hp->cmd_len > BLK_MAX_CDB)
1742 req->cmd = long_cmdp;
1743 memcpy(req->cmd, cmd, hp->cmd_len);
1744 req->cmd_len = hp->cmd_len;
1745
1746 srp->rq = rq;
1747 rq->end_io_data = srp;
1748 req->retries = SG_DEFAULT_RETRIES;
1749
1750 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1751 return 0;
1752
1753 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1754 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1755 !sfp->parentdp->device->host->unchecked_isa_dma &&
1756 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1757 md = NULL;
1758 else
1759 md = &map_data;
1760
1761 if (md) {
1762 mutex_lock(&sfp->f_mutex);
1763 if (dxfer_len <= rsv_schp->bufflen &&
1764 !sfp->res_in_use) {
1765 sfp->res_in_use = 1;
1766 sg_link_reserve(sfp, srp, dxfer_len);
1767 } else if ((hp->flags & SG_FLAG_MMAP_IO) && sfp->res_in_use) {
1768 mutex_unlock(&sfp->f_mutex);
1769 return -EBUSY;
1770 } else {
1771 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1772 if (res) {
1773 mutex_unlock(&sfp->f_mutex);
1774 return res;
1775 }
1776 }
1777 mutex_unlock(&sfp->f_mutex);
1778
1779 md->pages = req_schp->pages;
1780 md->page_order = req_schp->page_order;
1781 md->nr_entries = req_schp->k_use_sg;
1782 md->offset = 0;
1783 md->null_mapped = hp->dxferp ? 0 : 1;
1784 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1785 md->from_user = 1;
1786 else
1787 md->from_user = 0;
1788 }
1789
1790 if (iov_count) {
1791 struct iovec *iov = NULL;
1792 struct iov_iter i;
1793
1794 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1795 if (res < 0)
1796 return res;
1797
1798 iov_iter_truncate(&i, hp->dxfer_len);
1799 if (!iov_iter_count(&i)) {
1800 kfree(iov);
1801 return -EINVAL;
1802 }
1803
1804 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1805 kfree(iov);
1806 } else
1807 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1808 hp->dxfer_len, GFP_ATOMIC);
1809
1810 if (!res) {
1811 srp->bio = rq->bio;
1812
1813 if (!md) {
1814 req_schp->dio_in_use = 1;
1815 hp->info |= SG_INFO_DIRECT_IO;
1816 }
1817 }
1818 return res;
1819 }
1820
1821 static int
1822 sg_finish_rem_req(Sg_request *srp)
1823 {
1824 int ret = 0;
1825
1826 Sg_fd *sfp = srp->parentfp;
1827 Sg_scatter_hold *req_schp = &srp->data;
1828
1829 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1830 "sg_finish_rem_req: res_used=%d\n",
1831 (int) srp->res_used));
1832 if (srp->bio)
1833 ret = blk_rq_unmap_user(srp->bio);
1834
1835 if (srp->rq) {
1836 scsi_req_free_cmd(scsi_req(srp->rq));
1837 blk_put_request(srp->rq);
1838 }
1839
1840 if (srp->res_used)
1841 sg_unlink_reserve(sfp, srp);
1842 else
1843 sg_remove_scat(sfp, req_schp);
1844
1845 return ret;
1846 }
1847
1848 static int
1849 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1850 {
1851 int sg_bufflen = tablesize * sizeof(struct page *);
1852 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1853
1854 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1855 if (!schp->pages)
1856 return -ENOMEM;
1857 schp->sglist_len = sg_bufflen;
1858 return tablesize; /* number of scat_gath elements allocated */
1859 }
1860
1861 static int
1862 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1863 {
1864 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1865 int sg_tablesize = sfp->parentdp->sg_tablesize;
1866 int blk_size = buff_size, order;
1867 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1868 struct sg_device *sdp = sfp->parentdp;
1869
1870 if (blk_size < 0)
1871 return -EFAULT;
1872 if (0 == blk_size)
1873 ++blk_size; /* don't know why */
1874 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1875 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1876 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1877 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1878 buff_size, blk_size));
1879
1880 /* N.B. ret_sz carried into this block ... */
1881 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1882 if (mx_sc_elems < 0)
1883 return mx_sc_elems; /* most likely -ENOMEM */
1884
1885 num = scatter_elem_sz;
1886 if (unlikely(num != scatter_elem_sz_prev)) {
1887 if (num < PAGE_SIZE) {
1888 scatter_elem_sz = PAGE_SIZE;
1889 scatter_elem_sz_prev = PAGE_SIZE;
1890 } else
1891 scatter_elem_sz_prev = num;
1892 }
1893
1894 if (sdp->device->host->unchecked_isa_dma)
1895 gfp_mask |= GFP_DMA;
1896
1897 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1898 gfp_mask |= __GFP_ZERO;
1899
1900 order = get_order(num);
1901 retry:
1902 ret_sz = 1 << (PAGE_SHIFT + order);
1903
1904 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1905 k++, rem_sz -= ret_sz) {
1906
1907 num = (rem_sz > scatter_elem_sz_prev) ?
1908 scatter_elem_sz_prev : rem_sz;
1909
1910 schp->pages[k] = alloc_pages(gfp_mask, order);
1911 if (!schp->pages[k])
1912 goto out;
1913
1914 if (num == scatter_elem_sz_prev) {
1915 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1916 scatter_elem_sz = ret_sz;
1917 scatter_elem_sz_prev = ret_sz;
1918 }
1919 }
1920
1921 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1922 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1923 k, num, ret_sz));
1924 } /* end of for loop */
1925
1926 schp->page_order = order;
1927 schp->k_use_sg = k;
1928 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1929 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1930 k, rem_sz));
1931
1932 schp->bufflen = blk_size;
1933 if (rem_sz > 0) /* must have failed */
1934 return -ENOMEM;
1935 return 0;
1936 out:
1937 for (i = 0; i < k; i++)
1938 __free_pages(schp->pages[i], order);
1939
1940 if (--order >= 0)
1941 goto retry;
1942
1943 return -ENOMEM;
1944 }
1945
1946 static void
1947 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1948 {
1949 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1950 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1951 if (schp->pages && schp->sglist_len > 0) {
1952 if (!schp->dio_in_use) {
1953 int k;
1954
1955 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1956 SCSI_LOG_TIMEOUT(5,
1957 sg_printk(KERN_INFO, sfp->parentdp,
1958 "sg_remove_scat: k=%d, pg=0x%p\n",
1959 k, schp->pages[k]));
1960 __free_pages(schp->pages[k], schp->page_order);
1961 }
1962
1963 kfree(schp->pages);
1964 }
1965 }
1966 memset(schp, 0, sizeof (*schp));
1967 }
1968
1969 static int
1970 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1971 {
1972 Sg_scatter_hold *schp = &srp->data;
1973 int k, num;
1974
1975 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1976 "sg_read_oxfer: num_read_xfer=%d\n",
1977 num_read_xfer));
1978 if ((!outp) || (num_read_xfer <= 0))
1979 return 0;
1980
1981 num = 1 << (PAGE_SHIFT + schp->page_order);
1982 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1983 if (num > num_read_xfer) {
1984 if (__copy_to_user(outp, page_address(schp->pages[k]),
1985 num_read_xfer))
1986 return -EFAULT;
1987 break;
1988 } else {
1989 if (__copy_to_user(outp, page_address(schp->pages[k]),
1990 num))
1991 return -EFAULT;
1992 num_read_xfer -= num;
1993 if (num_read_xfer <= 0)
1994 break;
1995 outp += num;
1996 }
1997 }
1998
1999 return 0;
2000 }
2001
2002 static void
2003 sg_build_reserve(Sg_fd * sfp, int req_size)
2004 {
2005 Sg_scatter_hold *schp = &sfp->reserve;
2006
2007 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2008 "sg_build_reserve: req_size=%d\n", req_size));
2009 do {
2010 if (req_size < PAGE_SIZE)
2011 req_size = PAGE_SIZE;
2012 if (0 == sg_build_indirect(schp, sfp, req_size))
2013 return;
2014 else
2015 sg_remove_scat(sfp, schp);
2016 req_size >>= 1; /* divide by 2 */
2017 } while (req_size > (PAGE_SIZE / 2));
2018 }
2019
2020 static void
2021 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2022 {
2023 Sg_scatter_hold *req_schp = &srp->data;
2024 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2025 int k, num, rem;
2026
2027 srp->res_used = 1;
2028 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2029 "sg_link_reserve: size=%d\n", size));
2030 rem = size;
2031
2032 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2033 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2034 if (rem <= num) {
2035 req_schp->k_use_sg = k + 1;
2036 req_schp->sglist_len = rsv_schp->sglist_len;
2037 req_schp->pages = rsv_schp->pages;
2038
2039 req_schp->bufflen = size;
2040 req_schp->page_order = rsv_schp->page_order;
2041 break;
2042 } else
2043 rem -= num;
2044 }
2045
2046 if (k >= rsv_schp->k_use_sg)
2047 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2048 "sg_link_reserve: BAD size\n"));
2049 }
2050
2051 static void
2052 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2053 {
2054 Sg_scatter_hold *req_schp = &srp->data;
2055
2056 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2057 "sg_unlink_reserve: req->k_use_sg=%d\n",
2058 (int) req_schp->k_use_sg));
2059 req_schp->k_use_sg = 0;
2060 req_schp->bufflen = 0;
2061 req_schp->pages = NULL;
2062 req_schp->page_order = 0;
2063 req_schp->sglist_len = 0;
2064 srp->res_used = 0;
2065 /* Called without mutex lock to avoid deadlock */
2066 sfp->res_in_use = 0;
2067 }
2068
2069 static Sg_request *
2070 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2071 {
2072 Sg_request *resp;
2073 unsigned long iflags;
2074
2075 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2076 list_for_each_entry(resp, &sfp->rq_list, entry) {
2077 /* look for requests that are ready + not SG_IO owned */
2078 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2079 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2080 resp->done = 2; /* guard against other readers */
2081 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2082 return resp;
2083 }
2084 }
2085 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2086 return NULL;
2087 }
2088
2089 /* always adds to end of list */
2090 static Sg_request *
2091 sg_add_request(Sg_fd * sfp)
2092 {
2093 int k;
2094 unsigned long iflags;
2095 Sg_request *rp = sfp->req_arr;
2096
2097 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2098 if (!list_empty(&sfp->rq_list)) {
2099 if (!sfp->cmd_q)
2100 goto out_unlock;
2101
2102 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2103 if (!rp->parentfp)
2104 break;
2105 }
2106 if (k >= SG_MAX_QUEUE)
2107 goto out_unlock;
2108 }
2109 memset(rp, 0, sizeof (Sg_request));
2110 rp->parentfp = sfp;
2111 rp->header.duration = jiffies_to_msecs(jiffies);
2112 list_add_tail(&rp->entry, &sfp->rq_list);
2113 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2114 return rp;
2115 out_unlock:
2116 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2117 return NULL;
2118 }
2119
2120 /* Return of 1 for found; 0 for not found */
2121 static int
2122 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2123 {
2124 unsigned long iflags;
2125 int res = 0;
2126
2127 if (!sfp || !srp || list_empty(&sfp->rq_list))
2128 return res;
2129 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2130 if (!list_empty(&srp->entry)) {
2131 list_del(&srp->entry);
2132 srp->parentfp = NULL;
2133 res = 1;
2134 }
2135 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2136 return res;
2137 }
2138
2139 static Sg_fd *
2140 sg_add_sfp(Sg_device * sdp)
2141 {
2142 Sg_fd *sfp;
2143 unsigned long iflags;
2144 int bufflen;
2145
2146 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2147 if (!sfp)
2148 return ERR_PTR(-ENOMEM);
2149
2150 init_waitqueue_head(&sfp->read_wait);
2151 rwlock_init(&sfp->rq_list_lock);
2152 INIT_LIST_HEAD(&sfp->rq_list);
2153 kref_init(&sfp->f_ref);
2154 mutex_init(&sfp->f_mutex);
2155 sfp->timeout = SG_DEFAULT_TIMEOUT;
2156 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2157 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2158 sfp->cmd_q = SG_DEF_COMMAND_Q;
2159 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2160 sfp->parentdp = sdp;
2161 write_lock_irqsave(&sdp->sfd_lock, iflags);
2162 if (atomic_read(&sdp->detaching)) {
2163 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2164 return ERR_PTR(-ENODEV);
2165 }
2166 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2167 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2168 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2169 "sg_add_sfp: sfp=0x%p\n", sfp));
2170 if (unlikely(sg_big_buff != def_reserved_size))
2171 sg_big_buff = def_reserved_size;
2172
2173 bufflen = min_t(int, sg_big_buff,
2174 max_sectors_bytes(sdp->device->request_queue));
2175 sg_build_reserve(sfp, bufflen);
2176 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2177 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2178 sfp->reserve.bufflen,
2179 sfp->reserve.k_use_sg));
2180
2181 kref_get(&sdp->d_ref);
2182 __module_get(THIS_MODULE);
2183 return sfp;
2184 }
2185
2186 static void
2187 sg_remove_sfp_usercontext(struct work_struct *work)
2188 {
2189 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2190 struct sg_device *sdp = sfp->parentdp;
2191 Sg_request *srp;
2192 unsigned long iflags;
2193
2194 /* Cleanup any responses which were never read(). */
2195 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2196 while (!list_empty(&sfp->rq_list)) {
2197 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2198 sg_finish_rem_req(srp);
2199 list_del(&srp->entry);
2200 srp->parentfp = NULL;
2201 }
2202 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2203
2204 if (sfp->reserve.bufflen > 0) {
2205 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2206 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2207 (int) sfp->reserve.bufflen,
2208 (int) sfp->reserve.k_use_sg));
2209 sg_remove_scat(sfp, &sfp->reserve);
2210 }
2211
2212 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2213 "sg_remove_sfp: sfp=0x%p\n", sfp));
2214 kfree(sfp);
2215
2216 scsi_device_put(sdp->device);
2217 kref_put(&sdp->d_ref, sg_device_destroy);
2218 module_put(THIS_MODULE);
2219 }
2220
2221 static void
2222 sg_remove_sfp(struct kref *kref)
2223 {
2224 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2225 struct sg_device *sdp = sfp->parentdp;
2226 unsigned long iflags;
2227
2228 write_lock_irqsave(&sdp->sfd_lock, iflags);
2229 list_del(&sfp->sfd_siblings);
2230 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2231
2232 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2233 schedule_work(&sfp->ew.work);
2234 }
2235
2236 #ifdef CONFIG_SCSI_PROC_FS
2237 static int
2238 sg_idr_max_id(int id, void *p, void *data)
2239 {
2240 int *k = data;
2241
2242 if (*k < id)
2243 *k = id;
2244
2245 return 0;
2246 }
2247
2248 static int
2249 sg_last_dev(void)
2250 {
2251 int k = -1;
2252 unsigned long iflags;
2253
2254 read_lock_irqsave(&sg_index_lock, iflags);
2255 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2256 read_unlock_irqrestore(&sg_index_lock, iflags);
2257 return k + 1; /* origin 1 */
2258 }
2259 #endif
2260
2261 /* must be called with sg_index_lock held */
2262 static Sg_device *sg_lookup_dev(int dev)
2263 {
2264 return idr_find(&sg_index_idr, dev);
2265 }
2266
2267 static Sg_device *
2268 sg_get_dev(int dev)
2269 {
2270 struct sg_device *sdp;
2271 unsigned long flags;
2272
2273 read_lock_irqsave(&sg_index_lock, flags);
2274 sdp = sg_lookup_dev(dev);
2275 if (!sdp)
2276 sdp = ERR_PTR(-ENXIO);
2277 else if (atomic_read(&sdp->detaching)) {
2278 /* If sdp->detaching, then the refcount may already be 0, in
2279 * which case it would be a bug to do kref_get().
2280 */
2281 sdp = ERR_PTR(-ENODEV);
2282 } else
2283 kref_get(&sdp->d_ref);
2284 read_unlock_irqrestore(&sg_index_lock, flags);
2285
2286 return sdp;
2287 }
2288
2289 #ifdef CONFIG_SCSI_PROC_FS
2290
2291 static struct proc_dir_entry *sg_proc_sgp = NULL;
2292
2293 static char sg_proc_sg_dirname[] = "scsi/sg";
2294
2295 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2296
2297 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2298 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2299 size_t count, loff_t *off);
2300 static const struct file_operations adio_fops = {
2301 .owner = THIS_MODULE,
2302 .open = sg_proc_single_open_adio,
2303 .read = seq_read,
2304 .llseek = seq_lseek,
2305 .write = sg_proc_write_adio,
2306 .release = single_release,
2307 };
2308
2309 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2310 static ssize_t sg_proc_write_dressz(struct file *filp,
2311 const char __user *buffer, size_t count, loff_t *off);
2312 static const struct file_operations dressz_fops = {
2313 .owner = THIS_MODULE,
2314 .open = sg_proc_single_open_dressz,
2315 .read = seq_read,
2316 .llseek = seq_lseek,
2317 .write = sg_proc_write_dressz,
2318 .release = single_release,
2319 };
2320
2321 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2322 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2323 static const struct file_operations version_fops = {
2324 .owner = THIS_MODULE,
2325 .open = sg_proc_single_open_version,
2326 .read = seq_read,
2327 .llseek = seq_lseek,
2328 .release = single_release,
2329 };
2330
2331 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2332 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2333 static const struct file_operations devhdr_fops = {
2334 .owner = THIS_MODULE,
2335 .open = sg_proc_single_open_devhdr,
2336 .read = seq_read,
2337 .llseek = seq_lseek,
2338 .release = single_release,
2339 };
2340
2341 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2342 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2343 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2344 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2345 static void dev_seq_stop(struct seq_file *s, void *v);
2346 static const struct file_operations dev_fops = {
2347 .owner = THIS_MODULE,
2348 .open = sg_proc_open_dev,
2349 .read = seq_read,
2350 .llseek = seq_lseek,
2351 .release = seq_release,
2352 };
2353 static const struct seq_operations dev_seq_ops = {
2354 .start = dev_seq_start,
2355 .next = dev_seq_next,
2356 .stop = dev_seq_stop,
2357 .show = sg_proc_seq_show_dev,
2358 };
2359
2360 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2361 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2362 static const struct file_operations devstrs_fops = {
2363 .owner = THIS_MODULE,
2364 .open = sg_proc_open_devstrs,
2365 .read = seq_read,
2366 .llseek = seq_lseek,
2367 .release = seq_release,
2368 };
2369 static const struct seq_operations devstrs_seq_ops = {
2370 .start = dev_seq_start,
2371 .next = dev_seq_next,
2372 .stop = dev_seq_stop,
2373 .show = sg_proc_seq_show_devstrs,
2374 };
2375
2376 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2377 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2378 static const struct file_operations debug_fops = {
2379 .owner = THIS_MODULE,
2380 .open = sg_proc_open_debug,
2381 .read = seq_read,
2382 .llseek = seq_lseek,
2383 .release = seq_release,
2384 };
2385 static const struct seq_operations debug_seq_ops = {
2386 .start = dev_seq_start,
2387 .next = dev_seq_next,
2388 .stop = dev_seq_stop,
2389 .show = sg_proc_seq_show_debug,
2390 };
2391
2392
2393 struct sg_proc_leaf {
2394 const char * name;
2395 const struct file_operations * fops;
2396 };
2397
2398 static const struct sg_proc_leaf sg_proc_leaf_arr[] = {
2399 {"allow_dio", &adio_fops},
2400 {"debug", &debug_fops},
2401 {"def_reserved_size", &dressz_fops},
2402 {"device_hdr", &devhdr_fops},
2403 {"devices", &dev_fops},
2404 {"device_strs", &devstrs_fops},
2405 {"version", &version_fops}
2406 };
2407
2408 static int
2409 sg_proc_init(void)
2410 {
2411 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2412 int k;
2413
2414 sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2415 if (!sg_proc_sgp)
2416 return 1;
2417 for (k = 0; k < num_leaves; ++k) {
2418 const struct sg_proc_leaf *leaf = &sg_proc_leaf_arr[k];
2419 umode_t mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2420 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2421 }
2422 return 0;
2423 }
2424
2425 static void
2426 sg_proc_cleanup(void)
2427 {
2428 int k;
2429 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2430
2431 if (!sg_proc_sgp)
2432 return;
2433 for (k = 0; k < num_leaves; ++k)
2434 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2435 remove_proc_entry(sg_proc_sg_dirname, NULL);
2436 }
2437
2438
2439 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2440 {
2441 seq_printf(s, "%d\n", *((int *)s->private));
2442 return 0;
2443 }
2444
2445 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2446 {
2447 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2448 }
2449
2450 static ssize_t
2451 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2452 size_t count, loff_t *off)
2453 {
2454 int err;
2455 unsigned long num;
2456
2457 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2458 return -EACCES;
2459 err = kstrtoul_from_user(buffer, count, 0, &num);
2460 if (err)
2461 return err;
2462 sg_allow_dio = num ? 1 : 0;
2463 return count;
2464 }
2465
2466 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2467 {
2468 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2469 }
2470
2471 static ssize_t
2472 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2473 size_t count, loff_t *off)
2474 {
2475 int err;
2476 unsigned long k = ULONG_MAX;
2477
2478 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2479 return -EACCES;
2480
2481 err = kstrtoul_from_user(buffer, count, 0, &k);
2482 if (err)
2483 return err;
2484 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2485 sg_big_buff = k;
2486 return count;
2487 }
2488 return -ERANGE;
2489 }
2490
2491 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2492 {
2493 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2494 sg_version_date);
2495 return 0;
2496 }
2497
2498 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2499 {
2500 return single_open(file, sg_proc_seq_show_version, NULL);
2501 }
2502
2503 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2504 {
2505 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2506 return 0;
2507 }
2508
2509 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2510 {
2511 return single_open(file, sg_proc_seq_show_devhdr, NULL);
2512 }
2513
2514 struct sg_proc_deviter {
2515 loff_t index;
2516 size_t max;
2517 };
2518
2519 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2520 {
2521 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2522
2523 s->private = it;
2524 if (! it)
2525 return NULL;
2526
2527 it->index = *pos;
2528 it->max = sg_last_dev();
2529 if (it->index >= it->max)
2530 return NULL;
2531 return it;
2532 }
2533
2534 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2535 {
2536 struct sg_proc_deviter * it = s->private;
2537
2538 *pos = ++it->index;
2539 return (it->index < it->max) ? it : NULL;
2540 }
2541
2542 static void dev_seq_stop(struct seq_file *s, void *v)
2543 {
2544 kfree(s->private);
2545 }
2546
2547 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2548 {
2549 return seq_open(file, &dev_seq_ops);
2550 }
2551
2552 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2553 {
2554 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2555 Sg_device *sdp;
2556 struct scsi_device *scsidp;
2557 unsigned long iflags;
2558
2559 read_lock_irqsave(&sg_index_lock, iflags);
2560 sdp = it ? sg_lookup_dev(it->index) : NULL;
2561 if ((NULL == sdp) || (NULL == sdp->device) ||
2562 (atomic_read(&sdp->detaching)))
2563 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2564 else {
2565 scsidp = sdp->device;
2566 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2567 scsidp->host->host_no, scsidp->channel,
2568 scsidp->id, scsidp->lun, (int) scsidp->type,
2569 1,
2570 (int) scsidp->queue_depth,
2571 (int) atomic_read(&scsidp->device_busy),
2572 (int) scsi_device_online(scsidp));
2573 }
2574 read_unlock_irqrestore(&sg_index_lock, iflags);
2575 return 0;
2576 }
2577
2578 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2579 {
2580 return seq_open(file, &devstrs_seq_ops);
2581 }
2582
2583 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2584 {
2585 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2586 Sg_device *sdp;
2587 struct scsi_device *scsidp;
2588 unsigned long iflags;
2589
2590 read_lock_irqsave(&sg_index_lock, iflags);
2591 sdp = it ? sg_lookup_dev(it->index) : NULL;
2592 scsidp = sdp ? sdp->device : NULL;
2593 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2594 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2595 scsidp->vendor, scsidp->model, scsidp->rev);
2596 else
2597 seq_puts(s, "<no active device>\n");
2598 read_unlock_irqrestore(&sg_index_lock, iflags);
2599 return 0;
2600 }
2601
2602 /* must be called while holding sg_index_lock */
2603 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2604 {
2605 int k, new_interface, blen, usg;
2606 Sg_request *srp;
2607 Sg_fd *fp;
2608 const sg_io_hdr_t *hp;
2609 const char * cp;
2610 unsigned int ms;
2611
2612 k = 0;
2613 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2614 k++;
2615 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2616 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2617 "(res)sgat=%d low_dma=%d\n", k,
2618 jiffies_to_msecs(fp->timeout),
2619 fp->reserve.bufflen,
2620 (int) fp->reserve.k_use_sg,
2621 (int) sdp->device->host->unchecked_isa_dma);
2622 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2623 (int) fp->cmd_q, (int) fp->force_packid,
2624 (int) fp->keep_orphan);
2625 list_for_each_entry(srp, &fp->rq_list, entry) {
2626 hp = &srp->header;
2627 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2628 if (srp->res_used) {
2629 if (new_interface &&
2630 (SG_FLAG_MMAP_IO & hp->flags))
2631 cp = " mmap>> ";
2632 else
2633 cp = " rb>> ";
2634 } else {
2635 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2636 cp = " dio>> ";
2637 else
2638 cp = " ";
2639 }
2640 seq_puts(s, cp);
2641 blen = srp->data.bufflen;
2642 usg = srp->data.k_use_sg;
2643 seq_puts(s, srp->done ?
2644 ((1 == srp->done) ? "rcv:" : "fin:")
2645 : "act:");
2646 seq_printf(s, " id=%d blen=%d",
2647 srp->header.pack_id, blen);
2648 if (srp->done)
2649 seq_printf(s, " dur=%d", hp->duration);
2650 else {
2651 ms = jiffies_to_msecs(jiffies);
2652 seq_printf(s, " t_o/elap=%d/%d",
2653 (new_interface ? hp->timeout :
2654 jiffies_to_msecs(fp->timeout)),
2655 (ms > hp->duration ? ms - hp->duration : 0));
2656 }
2657 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2658 (int) srp->data.cmd_opcode);
2659 }
2660 if (list_empty(&fp->rq_list))
2661 seq_puts(s, " No requests active\n");
2662 read_unlock(&fp->rq_list_lock);
2663 }
2664 }
2665
2666 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2667 {
2668 return seq_open(file, &debug_seq_ops);
2669 }
2670
2671 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2672 {
2673 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2674 Sg_device *sdp;
2675 unsigned long iflags;
2676
2677 if (it && (0 == it->index))
2678 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2679 (int)it->max, sg_big_buff);
2680
2681 read_lock_irqsave(&sg_index_lock, iflags);
2682 sdp = it ? sg_lookup_dev(it->index) : NULL;
2683 if (NULL == sdp)
2684 goto skip;
2685 read_lock(&sdp->sfd_lock);
2686 if (!list_empty(&sdp->sfds)) {
2687 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2688 if (atomic_read(&sdp->detaching))
2689 seq_puts(s, "detaching pending close ");
2690 else if (sdp->device) {
2691 struct scsi_device *scsidp = sdp->device;
2692
2693 seq_printf(s, "%d:%d:%d:%llu em=%d",
2694 scsidp->host->host_no,
2695 scsidp->channel, scsidp->id,
2696 scsidp->lun,
2697 scsidp->host->hostt->emulated);
2698 }
2699 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2700 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2701 sg_proc_debug_helper(s, sdp);
2702 }
2703 read_unlock(&sdp->sfd_lock);
2704 skip:
2705 read_unlock_irqrestore(&sg_index_lock, iflags);
2706 return 0;
2707 }
2708
2709 #endif /* CONFIG_SCSI_PROC_FS */
2710
2711 module_init(init_sg);
2712 module_exit(exit_sg);
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