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dm thin metadata: fix __udivdi3 undefined on 32-bit
[linux/fpc-iii.git] / drivers / scsi / sg.c
blobe1639e80db536c3859674be8ceab57c385d3492c
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 #include <linux/cred.h> /* for sg_check_file_access() */
55
56 #include "scsi.h"
57 #include <scsi/scsi_dbg.h>
58 #include <scsi/scsi_host.h>
59 #include <scsi/scsi_driver.h>
60 #include <scsi/scsi_ioctl.h>
61 #include <scsi/sg.h>
62
63 #include "scsi_logging.h"
64
65 #ifdef CONFIG_SCSI_PROC_FS
66 #include <linux/proc_fs.h>
67 static char *sg_version_date = "20140603";
68
69 static int sg_proc_init(void);
70 static void sg_proc_cleanup(void);
71 #endif
72
73 #define SG_ALLOW_DIO_DEF 0
74
75 #define SG_MAX_DEVS 32768
76
77 /* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type
78 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater
79 * than 16 bytes are "variable length" whose length is a multiple of 4
80 */
81 #define SG_MAX_CDB_SIZE 252
82
83 /*
84 * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
85 * Then when using 32 bit integers x * m may overflow during the calculation.
86 * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
87 * calculates the same, but prevents the overflow when both m and d
88 * are "small" numbers (like HZ and USER_HZ).
89 * Of course an overflow is inavoidable if the result of muldiv doesn't fit
90 * in 32 bits.
91 */
92 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
93
94 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
95
96 int sg_big_buff = SG_DEF_RESERVED_SIZE;
97 /* N.B. This variable is readable and writeable via
98 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
99 of this size (or less if there is not enough memory) will be reserved
100 for use by this file descriptor. [Deprecated usage: this variable is also
101 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
102 the kernel (i.e. it is not a module).] */
103 static int def_reserved_size = -1; /* picks up init parameter */
104 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
105
106 static int scatter_elem_sz = SG_SCATTER_SZ;
107 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
108
109 #define SG_SECTOR_SZ 512
110
111 static int sg_add_device(struct device *, struct class_interface *);
112 static void sg_remove_device(struct device *, struct class_interface *);
113
114 static DEFINE_IDR(sg_index_idr);
115 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
116 file descriptor list for device */
117
118 static struct class_interface sg_interface = {
119 .add_dev = sg_add_device,
120 .remove_dev = sg_remove_device,
121 };
122
123 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
124 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
125 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
126 unsigned bufflen; /* Size of (aggregate) data buffer */
127 struct page **pages;
128 int page_order;
129 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
130 unsigned char cmd_opcode; /* first byte of command */
131 } Sg_scatter_hold;
132
133 struct sg_device; /* forward declarations */
134 struct sg_fd;
135
136 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
137 struct list_head entry; /* list entry */
138 struct sg_fd *parentfp; /* NULL -> not in use */
139 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
140 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
141 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
142 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
143 char orphan; /* 1 -> drop on sight, 0 -> normal */
144 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
145 /* done protected by rq_list_lock */
146 char done; /* 0->before bh, 1->before read, 2->read */
147 struct request *rq;
148 struct bio *bio;
149 struct execute_work ew;
150 } Sg_request;
151
152 typedef struct sg_fd { /* holds the state of a file descriptor */
153 struct list_head sfd_siblings; /* protected by device's sfd_lock */
154 struct sg_device *parentdp; /* owning device */
155 wait_queue_head_t read_wait; /* queue read until command done */
156 rwlock_t rq_list_lock; /* protect access to list in req_arr */
157 struct mutex f_mutex; /* protect against changes in this fd */
158 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
159 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
160 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
161 struct list_head rq_list; /* head of request list */
162 struct fasync_struct *async_qp; /* used by asynchronous notification */
163 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
164 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
165 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
166 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
167 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
168 char mmap_called; /* 0 -> mmap() never called on this fd */
169 char res_in_use; /* 1 -> 'reserve' array in use */
170 struct kref f_ref;
171 struct execute_work ew;
172 } Sg_fd;
173
174 typedef struct sg_device { /* holds the state of each scsi generic device */
175 struct scsi_device *device;
176 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */
177 struct mutex open_rel_lock; /* held when in open() or release() */
178 int sg_tablesize; /* adapter's max scatter-gather table size */
179 u32 index; /* device index number */
180 struct list_head sfds;
181 rwlock_t sfd_lock; /* protect access to sfd list */
182 atomic_t detaching; /* 0->device usable, 1->device detaching */
183 bool exclude; /* 1->open(O_EXCL) succeeded and is active */
184 int open_cnt; /* count of opens (perhaps < num(sfds) ) */
185 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
186 struct gendisk *disk;
187 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
188 struct kref d_ref;
189 } Sg_device;
190
191 /* tasklet or soft irq callback */
192 static void sg_rq_end_io(struct request *rq, int uptodate);
193 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
194 static int sg_finish_rem_req(Sg_request * srp);
195 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
196 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
197 Sg_request * srp);
198 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
199 const char __user *buf, size_t count, int blocking,
200 int read_only, int sg_io_owned, Sg_request **o_srp);
201 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
202 unsigned char *cmnd, int timeout, int blocking);
203 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
204 static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
205 static void sg_build_reserve(Sg_fd * sfp, int req_size);
206 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
207 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
208 static Sg_fd *sg_add_sfp(Sg_device * sdp);
209 static void sg_remove_sfp(struct kref *);
210 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
211 static Sg_request *sg_add_request(Sg_fd * sfp);
212 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
213 static Sg_device *sg_get_dev(int dev);
214 static void sg_device_destroy(struct kref *kref);
215
216 #define SZ_SG_HEADER sizeof(struct sg_header)
217 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
218 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
219 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
220
221 #define sg_printk(prefix, sdp, fmt, a...) \
222 sdev_prefix_printk(prefix, (sdp)->device, \
223 (sdp)->disk->disk_name, fmt, ##a)
224
225 /*
226 * The SCSI interfaces that use read() and write() as an asynchronous variant of
227 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways
228 * to trigger read() and write() calls from various contexts with elevated
229 * privileges. This can lead to kernel memory corruption (e.g. if these
230 * interfaces are called through splice()) and privilege escalation inside
231 * userspace (e.g. if a process with access to such a device passes a file
232 * descriptor to a SUID binary as stdin/stdout/stderr).
233 *
234 * This function provides protection for the legacy API by restricting the
235 * calling context.
236 */
237 static int sg_check_file_access(struct file *filp, const char *caller)
238 {
239 if (filp->f_cred != current_real_cred()) {
240 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
241 caller, task_tgid_vnr(current), current->comm);
242 return -EPERM;
243 }
244 if (unlikely(segment_eq(get_fs(), KERNEL_DS))) {
245 pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n",
246 caller, task_tgid_vnr(current), current->comm);
247 return -EACCES;
248 }
249 return 0;
250 }
251
252 static int sg_allow_access(struct file *filp, unsigned char *cmd)
253 {
254 struct sg_fd *sfp = filp->private_data;
255
256 if (sfp->parentdp->device->type == TYPE_SCANNER)
257 return 0;
258
259 return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
260 }
261
262 static int
263 open_wait(Sg_device *sdp, int flags)
264 {
265 int retval = 0;
266
267 if (flags & O_EXCL) {
268 while (sdp->open_cnt > 0) {
269 mutex_unlock(&sdp->open_rel_lock);
270 retval = wait_event_interruptible(sdp->open_wait,
271 (atomic_read(&sdp->detaching) ||
272 !sdp->open_cnt));
273 mutex_lock(&sdp->open_rel_lock);
274
275 if (retval) /* -ERESTARTSYS */
276 return retval;
277 if (atomic_read(&sdp->detaching))
278 return -ENODEV;
279 }
280 } else {
281 while (sdp->exclude) {
282 mutex_unlock(&sdp->open_rel_lock);
283 retval = wait_event_interruptible(sdp->open_wait,
284 (atomic_read(&sdp->detaching) ||
285 !sdp->exclude));
286 mutex_lock(&sdp->open_rel_lock);
287
288 if (retval) /* -ERESTARTSYS */
289 return retval;
290 if (atomic_read(&sdp->detaching))
291 return -ENODEV;
292 }
293 }
294
295 return retval;
296 }
297
298 /* Returns 0 on success, else a negated errno value */
299 static int
300 sg_open(struct inode *inode, struct file *filp)
301 {
302 int dev = iminor(inode);
303 int flags = filp->f_flags;
304 struct request_queue *q;
305 Sg_device *sdp;
306 Sg_fd *sfp;
307 int retval;
308
309 nonseekable_open(inode, filp);
310 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
311 return -EPERM; /* Can't lock it with read only access */
312 sdp = sg_get_dev(dev);
313 if (IS_ERR(sdp))
314 return PTR_ERR(sdp);
315
316 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
317 "sg_open: flags=0x%x\n", flags));
318
319 /* This driver's module count bumped by fops_get in <linux/fs.h> */
320 /* Prevent the device driver from vanishing while we sleep */
321 retval = scsi_device_get(sdp->device);
322 if (retval)
323 goto sg_put;
324
325 retval = scsi_autopm_get_device(sdp->device);
326 if (retval)
327 goto sdp_put;
328
329 /* scsi_block_when_processing_errors() may block so bypass
330 * check if O_NONBLOCK. Permits SCSI commands to be issued
331 * during error recovery. Tread carefully. */
332 if (!((flags & O_NONBLOCK) ||
333 scsi_block_when_processing_errors(sdp->device))) {
334 retval = -ENXIO;
335 /* we are in error recovery for this device */
336 goto error_out;
337 }
338
339 mutex_lock(&sdp->open_rel_lock);
340 if (flags & O_NONBLOCK) {
341 if (flags & O_EXCL) {
342 if (sdp->open_cnt > 0) {
343 retval = -EBUSY;
344 goto error_mutex_locked;
345 }
346 } else {
347 if (sdp->exclude) {
348 retval = -EBUSY;
349 goto error_mutex_locked;
350 }
351 }
352 } else {
353 retval = open_wait(sdp, flags);
354 if (retval) /* -ERESTARTSYS or -ENODEV */
355 goto error_mutex_locked;
356 }
357
358 /* N.B. at this point we are holding the open_rel_lock */
359 if (flags & O_EXCL)
360 sdp->exclude = true;
361
362 if (sdp->open_cnt < 1) { /* no existing opens */
363 sdp->sgdebug = 0;
364 q = sdp->device->request_queue;
365 sdp->sg_tablesize = queue_max_segments(q);
366 }
367 sfp = sg_add_sfp(sdp);
368 if (IS_ERR(sfp)) {
369 retval = PTR_ERR(sfp);
370 goto out_undo;
371 }
372
373 filp->private_data = sfp;
374 sdp->open_cnt++;
375 mutex_unlock(&sdp->open_rel_lock);
376
377 retval = 0;
378 sg_put:
379 kref_put(&sdp->d_ref, sg_device_destroy);
380 return retval;
381
382 out_undo:
383 if (flags & O_EXCL) {
384 sdp->exclude = false; /* undo if error */
385 wake_up_interruptible(&sdp->open_wait);
386 }
387 error_mutex_locked:
388 mutex_unlock(&sdp->open_rel_lock);
389 error_out:
390 scsi_autopm_put_device(sdp->device);
391 sdp_put:
392 scsi_device_put(sdp->device);
393 goto sg_put;
394 }
395
396 /* Release resources associated with a successful sg_open()
397 * Returns 0 on success, else a negated errno value */
398 static int
399 sg_release(struct inode *inode, struct file *filp)
400 {
401 Sg_device *sdp;
402 Sg_fd *sfp;
403
404 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
405 return -ENXIO;
406 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
407
408 mutex_lock(&sdp->open_rel_lock);
409 scsi_autopm_put_device(sdp->device);
410 kref_put(&sfp->f_ref, sg_remove_sfp);
411 sdp->open_cnt--;
412
413 /* possibly many open()s waiting on exlude clearing, start many;
414 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
415 if (sdp->exclude) {
416 sdp->exclude = false;
417 wake_up_interruptible_all(&sdp->open_wait);
418 } else if (0 == sdp->open_cnt) {
419 wake_up_interruptible(&sdp->open_wait);
420 }
421 mutex_unlock(&sdp->open_rel_lock);
422 return 0;
423 }
424
425 static ssize_t
426 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
427 {
428 Sg_device *sdp;
429 Sg_fd *sfp;
430 Sg_request *srp;
431 int req_pack_id = -1;
432 sg_io_hdr_t *hp;
433 struct sg_header *old_hdr = NULL;
434 int retval = 0;
435
436 /*
437 * This could cause a response to be stranded. Close the associated
438 * file descriptor to free up any resources being held.
439 */
440 retval = sg_check_file_access(filp, __func__);
441 if (retval)
442 return retval;
443
444 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
445 return -ENXIO;
446 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
447 "sg_read: count=%d\n", (int) count));
448
449 if (!access_ok(VERIFY_WRITE, buf, count))
450 return -EFAULT;
451 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
452 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
453 if (!old_hdr)
454 return -ENOMEM;
455 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
456 retval = -EFAULT;
457 goto free_old_hdr;
458 }
459 if (old_hdr->reply_len < 0) {
460 if (count >= SZ_SG_IO_HDR) {
461 sg_io_hdr_t *new_hdr;
462 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
463 if (!new_hdr) {
464 retval = -ENOMEM;
465 goto free_old_hdr;
466 }
467 retval =__copy_from_user
468 (new_hdr, buf, SZ_SG_IO_HDR);
469 req_pack_id = new_hdr->pack_id;
470 kfree(new_hdr);
471 if (retval) {
472 retval = -EFAULT;
473 goto free_old_hdr;
474 }
475 }
476 } else
477 req_pack_id = old_hdr->pack_id;
478 }
479 srp = sg_get_rq_mark(sfp, req_pack_id);
480 if (!srp) { /* now wait on packet to arrive */
481 if (atomic_read(&sdp->detaching)) {
482 retval = -ENODEV;
483 goto free_old_hdr;
484 }
485 if (filp->f_flags & O_NONBLOCK) {
486 retval = -EAGAIN;
487 goto free_old_hdr;
488 }
489 retval = wait_event_interruptible(sfp->read_wait,
490 (atomic_read(&sdp->detaching) ||
491 (srp = sg_get_rq_mark(sfp, req_pack_id))));
492 if (atomic_read(&sdp->detaching)) {
493 retval = -ENODEV;
494 goto free_old_hdr;
495 }
496 if (retval) {
497 /* -ERESTARTSYS as signal hit process */
498 goto free_old_hdr;
499 }
500 }
501 if (srp->header.interface_id != '\0') {
502 retval = sg_new_read(sfp, buf, count, srp);
503 goto free_old_hdr;
504 }
505
506 hp = &srp->header;
507 if (old_hdr == NULL) {
508 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
509 if (! old_hdr) {
510 retval = -ENOMEM;
511 goto free_old_hdr;
512 }
513 }
514 memset(old_hdr, 0, SZ_SG_HEADER);
515 old_hdr->reply_len = (int) hp->timeout;
516 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
517 old_hdr->pack_id = hp->pack_id;
518 old_hdr->twelve_byte =
519 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
520 old_hdr->target_status = hp->masked_status;
521 old_hdr->host_status = hp->host_status;
522 old_hdr->driver_status = hp->driver_status;
523 if ((CHECK_CONDITION & hp->masked_status) ||
524 (DRIVER_SENSE & hp->driver_status))
525 memcpy(old_hdr->sense_buffer, srp->sense_b,
526 sizeof (old_hdr->sense_buffer));
527 switch (hp->host_status) {
528 /* This setup of 'result' is for backward compatibility and is best
529 ignored by the user who should use target, host + driver status */
530 case DID_OK:
531 case DID_PASSTHROUGH:
532 case DID_SOFT_ERROR:
533 old_hdr->result = 0;
534 break;
535 case DID_NO_CONNECT:
536 case DID_BUS_BUSY:
537 case DID_TIME_OUT:
538 old_hdr->result = EBUSY;
539 break;
540 case DID_BAD_TARGET:
541 case DID_ABORT:
542 case DID_PARITY:
543 case DID_RESET:
544 case DID_BAD_INTR:
545 old_hdr->result = EIO;
546 break;
547 case DID_ERROR:
548 old_hdr->result = (srp->sense_b[0] == 0 &&
549 hp->masked_status == GOOD) ? 0 : EIO;
550 break;
551 default:
552 old_hdr->result = EIO;
553 break;
554 }
555
556 /* Now copy the result back to the user buffer. */
557 if (count >= SZ_SG_HEADER) {
558 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
559 retval = -EFAULT;
560 goto free_old_hdr;
561 }
562 buf += SZ_SG_HEADER;
563 if (count > old_hdr->reply_len)
564 count = old_hdr->reply_len;
565 if (count > SZ_SG_HEADER) {
566 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
567 retval = -EFAULT;
568 goto free_old_hdr;
569 }
570 }
571 } else
572 count = (old_hdr->result == 0) ? 0 : -EIO;
573 sg_finish_rem_req(srp);
574 sg_remove_request(sfp, srp);
575 retval = count;
576 free_old_hdr:
577 kfree(old_hdr);
578 return retval;
579 }
580
581 static ssize_t
582 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
583 {
584 sg_io_hdr_t *hp = &srp->header;
585 int err = 0, err2;
586 int len;
587
588 if (count < SZ_SG_IO_HDR) {
589 err = -EINVAL;
590 goto err_out;
591 }
592 hp->sb_len_wr = 0;
593 if ((hp->mx_sb_len > 0) && hp->sbp) {
594 if ((CHECK_CONDITION & hp->masked_status) ||
595 (DRIVER_SENSE & hp->driver_status)) {
596 int sb_len = SCSI_SENSE_BUFFERSIZE;
597 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
598 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
599 len = (len > sb_len) ? sb_len : len;
600 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
601 err = -EFAULT;
602 goto err_out;
603 }
604 hp->sb_len_wr = len;
605 }
606 }
607 if (hp->masked_status || hp->host_status || hp->driver_status)
608 hp->info |= SG_INFO_CHECK;
609 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
610 err = -EFAULT;
611 goto err_out;
612 }
613 err_out:
614 err2 = sg_finish_rem_req(srp);
615 sg_remove_request(sfp, srp);
616 return err ? : err2 ? : count;
617 }
618
619 static ssize_t
620 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
621 {
622 int mxsize, cmd_size, k;
623 int input_size, blocking;
624 unsigned char opcode;
625 Sg_device *sdp;
626 Sg_fd *sfp;
627 Sg_request *srp;
628 struct sg_header old_hdr;
629 sg_io_hdr_t *hp;
630 unsigned char cmnd[SG_MAX_CDB_SIZE];
631 int retval;
632
633 retval = sg_check_file_access(filp, __func__);
634 if (retval)
635 return retval;
636
637 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
638 return -ENXIO;
639 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
640 "sg_write: count=%d\n", (int) count));
641 if (atomic_read(&sdp->detaching))
642 return -ENODEV;
643 if (!((filp->f_flags & O_NONBLOCK) ||
644 scsi_block_when_processing_errors(sdp->device)))
645 return -ENXIO;
646
647 if (!access_ok(VERIFY_READ, buf, count))
648 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
649 if (count < SZ_SG_HEADER)
650 return -EIO;
651 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
652 return -EFAULT;
653 blocking = !(filp->f_flags & O_NONBLOCK);
654 if (old_hdr.reply_len < 0)
655 return sg_new_write(sfp, filp, buf, count,
656 blocking, 0, 0, NULL);
657 if (count < (SZ_SG_HEADER + 6))
658 return -EIO; /* The minimum scsi command length is 6 bytes. */
659
660 if (!(srp = sg_add_request(sfp))) {
661 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
662 "sg_write: queue full\n"));
663 return -EDOM;
664 }
665 buf += SZ_SG_HEADER;
666 __get_user(opcode, buf);
667 mutex_lock(&sfp->f_mutex);
668 if (sfp->next_cmd_len > 0) {
669 cmd_size = sfp->next_cmd_len;
670 sfp->next_cmd_len = 0; /* reset so only this write() effected */
671 } else {
672 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
673 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
674 cmd_size = 12;
675 }
676 mutex_unlock(&sfp->f_mutex);
677 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
678 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
679 /* Determine buffer size. */
680 input_size = count - cmd_size;
681 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
682 mxsize -= SZ_SG_HEADER;
683 input_size -= SZ_SG_HEADER;
684 if (input_size < 0) {
685 sg_remove_request(sfp, srp);
686 return -EIO; /* User did not pass enough bytes for this command. */
687 }
688 hp = &srp->header;
689 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
690 hp->cmd_len = (unsigned char) cmd_size;
691 hp->iovec_count = 0;
692 hp->mx_sb_len = 0;
693 if (input_size > 0)
694 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
695 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
696 else
697 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
698 hp->dxfer_len = mxsize;
699 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
700 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
701 hp->dxferp = (char __user *)buf + cmd_size;
702 else
703 hp->dxferp = NULL;
704 hp->sbp = NULL;
705 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
706 hp->flags = input_size; /* structure abuse ... */
707 hp->pack_id = old_hdr.pack_id;
708 hp->usr_ptr = NULL;
709 if (__copy_from_user(cmnd, buf, cmd_size))
710 return -EFAULT;
711 /*
712 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
713 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
714 * is a non-zero input_size, so emit a warning.
715 */
716 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
717 printk_ratelimited(KERN_WARNING
718 "sg_write: data in/out %d/%d bytes "
719 "for SCSI command 0x%x-- guessing "
720 "data in;\n program %s not setting "
721 "count and/or reply_len properly\n",
722 old_hdr.reply_len - (int)SZ_SG_HEADER,
723 input_size, (unsigned int) cmnd[0],
724 current->comm);
725 }
726 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
727 return (k < 0) ? k : count;
728 }
729
730 static ssize_t
731 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
732 size_t count, int blocking, int read_only, int sg_io_owned,
733 Sg_request **o_srp)
734 {
735 int k;
736 Sg_request *srp;
737 sg_io_hdr_t *hp;
738 unsigned char cmnd[SG_MAX_CDB_SIZE];
739 int timeout;
740 unsigned long ul_timeout;
741
742 if (count < SZ_SG_IO_HDR)
743 return -EINVAL;
744 if (!access_ok(VERIFY_READ, buf, count))
745 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
746
747 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
748 if (!(srp = sg_add_request(sfp))) {
749 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
750 "sg_new_write: queue full\n"));
751 return -EDOM;
752 }
753 srp->sg_io_owned = sg_io_owned;
754 hp = &srp->header;
755 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
756 sg_remove_request(sfp, srp);
757 return -EFAULT;
758 }
759 if (hp->interface_id != 'S') {
760 sg_remove_request(sfp, srp);
761 return -ENOSYS;
762 }
763 if (hp->flags & SG_FLAG_MMAP_IO) {
764 if (hp->dxfer_len > sfp->reserve.bufflen) {
765 sg_remove_request(sfp, srp);
766 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
767 }
768 if (hp->flags & SG_FLAG_DIRECT_IO) {
769 sg_remove_request(sfp, srp);
770 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
771 }
772 if (sfp->res_in_use) {
773 sg_remove_request(sfp, srp);
774 return -EBUSY; /* reserve buffer already being used */
775 }
776 }
777 ul_timeout = msecs_to_jiffies(srp->header.timeout);
778 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
779 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
780 sg_remove_request(sfp, srp);
781 return -EMSGSIZE;
782 }
783 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
784 sg_remove_request(sfp, srp);
785 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
786 }
787 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
788 sg_remove_request(sfp, srp);
789 return -EFAULT;
790 }
791 if (read_only && sg_allow_access(file, cmnd)) {
792 sg_remove_request(sfp, srp);
793 return -EPERM;
794 }
795 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
796 if (k < 0)
797 return k;
798 if (o_srp)
799 *o_srp = srp;
800 return count;
801 }
802
803 static int
804 sg_common_write(Sg_fd * sfp, Sg_request * srp,
805 unsigned char *cmnd, int timeout, int blocking)
806 {
807 int k, at_head;
808 Sg_device *sdp = sfp->parentdp;
809 sg_io_hdr_t *hp = &srp->header;
810
811 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
812 hp->status = 0;
813 hp->masked_status = 0;
814 hp->msg_status = 0;
815 hp->info = 0;
816 hp->host_status = 0;
817 hp->driver_status = 0;
818 hp->resid = 0;
819 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
820 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
821 (int) cmnd[0], (int) hp->cmd_len));
822
823 if (hp->dxfer_len >= SZ_256M)
824 return -EINVAL;
825
826 k = sg_start_req(srp, cmnd);
827 if (k) {
828 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
829 "sg_common_write: start_req err=%d\n", k));
830 sg_finish_rem_req(srp);
831 sg_remove_request(sfp, srp);
832 return k; /* probably out of space --> ENOMEM */
833 }
834 if (atomic_read(&sdp->detaching)) {
835 if (srp->bio) {
836 if (srp->rq->cmd != srp->rq->__cmd)
837 kfree(srp->rq->cmd);
838
839 blk_end_request_all(srp->rq, -EIO);
840 srp->rq = NULL;
841 }
842
843 sg_finish_rem_req(srp);
844 sg_remove_request(sfp, srp);
845 return -ENODEV;
846 }
847
848 hp->duration = jiffies_to_msecs(jiffies);
849 if (hp->interface_id != '\0' && /* v3 (or later) interface */
850 (SG_FLAG_Q_AT_TAIL & hp->flags))
851 at_head = 0;
852 else
853 at_head = 1;
854
855 srp->rq->timeout = timeout;
856 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
857 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
858 srp->rq, at_head, sg_rq_end_io);
859 return 0;
860 }
861
862 static int srp_done(Sg_fd *sfp, Sg_request *srp)
863 {
864 unsigned long flags;
865 int ret;
866
867 read_lock_irqsave(&sfp->rq_list_lock, flags);
868 ret = srp->done;
869 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
870 return ret;
871 }
872
873 static int max_sectors_bytes(struct request_queue *q)
874 {
875 unsigned int max_sectors = queue_max_sectors(q);
876
877 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
878
879 return max_sectors << 9;
880 }
881
882 static void
883 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
884 {
885 Sg_request *srp;
886 int val;
887 unsigned int ms;
888
889 val = 0;
890 list_for_each_entry(srp, &sfp->rq_list, entry) {
891 if (val >= SG_MAX_QUEUE)
892 break;
893 rinfo[val].req_state = srp->done + 1;
894 rinfo[val].problem =
895 srp->header.masked_status &
896 srp->header.host_status &
897 srp->header.driver_status;
898 if (srp->done)
899 rinfo[val].duration =
900 srp->header.duration;
901 else {
902 ms = jiffies_to_msecs(jiffies);
903 rinfo[val].duration =
904 (ms > srp->header.duration) ?
905 (ms - srp->header.duration) : 0;
906 }
907 rinfo[val].orphan = srp->orphan;
908 rinfo[val].sg_io_owned = srp->sg_io_owned;
909 rinfo[val].pack_id = srp->header.pack_id;
910 rinfo[val].usr_ptr = srp->header.usr_ptr;
911 val++;
912 }
913 }
914
915 static long
916 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
917 {
918 void __user *p = (void __user *)arg;
919 int __user *ip = p;
920 int result, val, read_only;
921 Sg_device *sdp;
922 Sg_fd *sfp;
923 Sg_request *srp;
924 unsigned long iflags;
925
926 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
927 return -ENXIO;
928
929 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
930 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
931 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
932
933 switch (cmd_in) {
934 case SG_IO:
935 if (atomic_read(&sdp->detaching))
936 return -ENODEV;
937 if (!scsi_block_when_processing_errors(sdp->device))
938 return -ENXIO;
939 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
940 return -EFAULT;
941 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
942 1, read_only, 1, &srp);
943 if (result < 0)
944 return result;
945 result = wait_event_interruptible(sfp->read_wait,
946 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
947 if (atomic_read(&sdp->detaching))
948 return -ENODEV;
949 write_lock_irq(&sfp->rq_list_lock);
950 if (srp->done) {
951 srp->done = 2;
952 write_unlock_irq(&sfp->rq_list_lock);
953 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
954 return (result < 0) ? result : 0;
955 }
956 srp->orphan = 1;
957 write_unlock_irq(&sfp->rq_list_lock);
958 return result; /* -ERESTARTSYS because signal hit process */
959 case SG_SET_TIMEOUT:
960 result = get_user(val, ip);
961 if (result)
962 return result;
963 if (val < 0)
964 return -EIO;
965 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
966 val = MULDIV (INT_MAX, USER_HZ, HZ);
967 sfp->timeout_user = val;
968 sfp->timeout = MULDIV (val, HZ, USER_HZ);
969
970 return 0;
971 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
972 /* strange ..., for backward compatibility */
973 return sfp->timeout_user;
974 case SG_SET_FORCE_LOW_DMA:
975 /*
976 * N.B. This ioctl never worked properly, but failed to
977 * return an error value. So returning '0' to keep compability
978 * with legacy applications.
979 */
980 return 0;
981 case SG_GET_LOW_DMA:
982 return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
983 case SG_GET_SCSI_ID:
984 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
985 return -EFAULT;
986 else {
987 sg_scsi_id_t __user *sg_idp = p;
988
989 if (atomic_read(&sdp->detaching))
990 return -ENODEV;
991 __put_user((int) sdp->device->host->host_no,
992 &sg_idp->host_no);
993 __put_user((int) sdp->device->channel,
994 &sg_idp->channel);
995 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
996 __put_user((int) sdp->device->lun, &sg_idp->lun);
997 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
998 __put_user((short) sdp->device->host->cmd_per_lun,
999 &sg_idp->h_cmd_per_lun);
1000 __put_user((short) sdp->device->queue_depth,
1001 &sg_idp->d_queue_depth);
1002 __put_user(0, &sg_idp->unused[0]);
1003 __put_user(0, &sg_idp->unused[1]);
1004 return 0;
1005 }
1006 case SG_SET_FORCE_PACK_ID:
1007 result = get_user(val, ip);
1008 if (result)
1009 return result;
1010 sfp->force_packid = val ? 1 : 0;
1011 return 0;
1012 case SG_GET_PACK_ID:
1013 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
1014 return -EFAULT;
1015 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1016 list_for_each_entry(srp, &sfp->rq_list, entry) {
1017 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1018 read_unlock_irqrestore(&sfp->rq_list_lock,
1019 iflags);
1020 __put_user(srp->header.pack_id, ip);
1021 return 0;
1022 }
1023 }
1024 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1025 __put_user(-1, ip);
1026 return 0;
1027 case SG_GET_NUM_WAITING:
1028 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1029 val = 0;
1030 list_for_each_entry(srp, &sfp->rq_list, entry) {
1031 if ((1 == srp->done) && (!srp->sg_io_owned))
1032 ++val;
1033 }
1034 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1035 return put_user(val, ip);
1036 case SG_GET_SG_TABLESIZE:
1037 return put_user(sdp->sg_tablesize, ip);
1038 case SG_SET_RESERVED_SIZE:
1039 result = get_user(val, ip);
1040 if (result)
1041 return result;
1042 if (val < 0)
1043 return -EINVAL;
1044 val = min_t(int, val,
1045 max_sectors_bytes(sdp->device->request_queue));
1046 mutex_lock(&sfp->f_mutex);
1047 if (val != sfp->reserve.bufflen) {
1048 if (sfp->mmap_called ||
1049 sfp->res_in_use) {
1050 mutex_unlock(&sfp->f_mutex);
1051 return -EBUSY;
1052 }
1053
1054 sg_remove_scat(sfp, &sfp->reserve);
1055 sg_build_reserve(sfp, val);
1056 }
1057 mutex_unlock(&sfp->f_mutex);
1058 return 0;
1059 case SG_GET_RESERVED_SIZE:
1060 val = min_t(int, sfp->reserve.bufflen,
1061 max_sectors_bytes(sdp->device->request_queue));
1062 return put_user(val, ip);
1063 case SG_SET_COMMAND_Q:
1064 result = get_user(val, ip);
1065 if (result)
1066 return result;
1067 sfp->cmd_q = val ? 1 : 0;
1068 return 0;
1069 case SG_GET_COMMAND_Q:
1070 return put_user((int) sfp->cmd_q, ip);
1071 case SG_SET_KEEP_ORPHAN:
1072 result = get_user(val, ip);
1073 if (result)
1074 return result;
1075 sfp->keep_orphan = val;
1076 return 0;
1077 case SG_GET_KEEP_ORPHAN:
1078 return put_user((int) sfp->keep_orphan, ip);
1079 case SG_NEXT_CMD_LEN:
1080 result = get_user(val, ip);
1081 if (result)
1082 return result;
1083 if (val > SG_MAX_CDB_SIZE)
1084 return -ENOMEM;
1085 sfp->next_cmd_len = (val > 0) ? val : 0;
1086 return 0;
1087 case SG_GET_VERSION_NUM:
1088 return put_user(sg_version_num, ip);
1089 case SG_GET_ACCESS_COUNT:
1090 /* faked - we don't have a real access count anymore */
1091 val = (sdp->device ? 1 : 0);
1092 return put_user(val, ip);
1093 case SG_GET_REQUEST_TABLE:
1094 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
1095 return -EFAULT;
1096 else {
1097 sg_req_info_t *rinfo;
1098
1099 rinfo = kzalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
1100 GFP_KERNEL);
1101 if (!rinfo)
1102 return -ENOMEM;
1103 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1104 sg_fill_request_table(sfp, rinfo);
1105 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1106 result = __copy_to_user(p, rinfo,
1107 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1108 result = result ? -EFAULT : 0;
1109 kfree(rinfo);
1110 return result;
1111 }
1112 case SG_EMULATED_HOST:
1113 if (atomic_read(&sdp->detaching))
1114 return -ENODEV;
1115 return put_user(sdp->device->host->hostt->emulated, ip);
1116 case SCSI_IOCTL_SEND_COMMAND:
1117 if (atomic_read(&sdp->detaching))
1118 return -ENODEV;
1119 if (read_only) {
1120 unsigned char opcode = WRITE_6;
1121 Scsi_Ioctl_Command __user *siocp = p;
1122
1123 if (copy_from_user(&opcode, siocp->data, 1))
1124 return -EFAULT;
1125 if (sg_allow_access(filp, &opcode))
1126 return -EPERM;
1127 }
1128 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1129 case SG_SET_DEBUG:
1130 result = get_user(val, ip);
1131 if (result)
1132 return result;
1133 sdp->sgdebug = (char) val;
1134 return 0;
1135 case BLKSECTGET:
1136 return put_user(max_sectors_bytes(sdp->device->request_queue),
1137 ip);
1138 case BLKTRACESETUP:
1139 return blk_trace_setup(sdp->device->request_queue,
1140 sdp->disk->disk_name,
1141 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1142 NULL,
1143 (char *)arg);
1144 case BLKTRACESTART:
1145 return blk_trace_startstop(sdp->device->request_queue, 1);
1146 case BLKTRACESTOP:
1147 return blk_trace_startstop(sdp->device->request_queue, 0);
1148 case BLKTRACETEARDOWN:
1149 return blk_trace_remove(sdp->device->request_queue);
1150 case SCSI_IOCTL_GET_IDLUN:
1151 case SCSI_IOCTL_GET_BUS_NUMBER:
1152 case SCSI_IOCTL_PROBE_HOST:
1153 case SG_GET_TRANSFORM:
1154 case SG_SCSI_RESET:
1155 if (atomic_read(&sdp->detaching))
1156 return -ENODEV;
1157 break;
1158 default:
1159 if (read_only)
1160 return -EPERM; /* don't know so take safe approach */
1161 break;
1162 }
1163
1164 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1165 cmd_in, filp->f_flags & O_NDELAY);
1166 if (result)
1167 return result;
1168 return scsi_ioctl(sdp->device, cmd_in, p);
1169 }
1170
1171 #ifdef CONFIG_COMPAT
1172 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1173 {
1174 Sg_device *sdp;
1175 Sg_fd *sfp;
1176 struct scsi_device *sdev;
1177
1178 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1179 return -ENXIO;
1180
1181 sdev = sdp->device;
1182 if (sdev->host->hostt->compat_ioctl) {
1183 int ret;
1184
1185 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1186
1187 return ret;
1188 }
1189
1190 return -ENOIOCTLCMD;
1191 }
1192 #endif
1193
1194 static unsigned int
1195 sg_poll(struct file *filp, poll_table * wait)
1196 {
1197 unsigned int res = 0;
1198 Sg_device *sdp;
1199 Sg_fd *sfp;
1200 Sg_request *srp;
1201 int count = 0;
1202 unsigned long iflags;
1203
1204 sfp = filp->private_data;
1205 if (!sfp)
1206 return POLLERR;
1207 sdp = sfp->parentdp;
1208 if (!sdp)
1209 return POLLERR;
1210 poll_wait(filp, &sfp->read_wait, wait);
1211 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1212 list_for_each_entry(srp, &sfp->rq_list, entry) {
1213 /* if any read waiting, flag it */
1214 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1215 res = POLLIN | POLLRDNORM;
1216 ++count;
1217 }
1218 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1219
1220 if (atomic_read(&sdp->detaching))
1221 res |= POLLHUP;
1222 else if (!sfp->cmd_q) {
1223 if (0 == count)
1224 res |= POLLOUT | POLLWRNORM;
1225 } else if (count < SG_MAX_QUEUE)
1226 res |= POLLOUT | POLLWRNORM;
1227 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1228 "sg_poll: res=0x%x\n", (int) res));
1229 return res;
1230 }
1231
1232 static int
1233 sg_fasync(int fd, struct file *filp, int mode)
1234 {
1235 Sg_device *sdp;
1236 Sg_fd *sfp;
1237
1238 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1239 return -ENXIO;
1240 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1241 "sg_fasync: mode=%d\n", mode));
1242
1243 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1244 }
1245
1246 static int
1247 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1248 {
1249 Sg_fd *sfp;
1250 unsigned long offset, len, sa;
1251 Sg_scatter_hold *rsv_schp;
1252 int k, length;
1253
1254 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1255 return VM_FAULT_SIGBUS;
1256 rsv_schp = &sfp->reserve;
1257 offset = vmf->pgoff << PAGE_SHIFT;
1258 if (offset >= rsv_schp->bufflen)
1259 return VM_FAULT_SIGBUS;
1260 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1261 "sg_vma_fault: offset=%lu, scatg=%d\n",
1262 offset, rsv_schp->k_use_sg));
1263 sa = vma->vm_start;
1264 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1265 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1266 len = vma->vm_end - sa;
1267 len = (len < length) ? len : length;
1268 if (offset < len) {
1269 struct page *page = nth_page(rsv_schp->pages[k],
1270 offset >> PAGE_SHIFT);
1271 get_page(page); /* increment page count */
1272 vmf->page = page;
1273 return 0; /* success */
1274 }
1275 sa += len;
1276 offset -= len;
1277 }
1278
1279 return VM_FAULT_SIGBUS;
1280 }
1281
1282 static const struct vm_operations_struct sg_mmap_vm_ops = {
1283 .fault = sg_vma_fault,
1284 };
1285
1286 static int
1287 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1288 {
1289 Sg_fd *sfp;
1290 unsigned long req_sz, len, sa;
1291 Sg_scatter_hold *rsv_schp;
1292 int k, length;
1293 int ret = 0;
1294
1295 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1296 return -ENXIO;
1297 req_sz = vma->vm_end - vma->vm_start;
1298 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1299 "sg_mmap starting, vm_start=%p, len=%d\n",
1300 (void *) vma->vm_start, (int) req_sz));
1301 if (vma->vm_pgoff)
1302 return -EINVAL; /* want no offset */
1303 rsv_schp = &sfp->reserve;
1304 mutex_lock(&sfp->f_mutex);
1305 if (req_sz > rsv_schp->bufflen) {
1306 ret = -ENOMEM; /* cannot map more than reserved buffer */
1307 goto out;
1308 }
1309
1310 sa = vma->vm_start;
1311 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1312 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1313 len = vma->vm_end - sa;
1314 len = (len < length) ? len : length;
1315 sa += len;
1316 }
1317
1318 sfp->mmap_called = 1;
1319 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1320 vma->vm_private_data = sfp;
1321 vma->vm_ops = &sg_mmap_vm_ops;
1322 out:
1323 mutex_unlock(&sfp->f_mutex);
1324 return ret;
1325 }
1326
1327 static void
1328 sg_rq_end_io_usercontext(struct work_struct *work)
1329 {
1330 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1331 struct sg_fd *sfp = srp->parentfp;
1332
1333 sg_finish_rem_req(srp);
1334 sg_remove_request(sfp, srp);
1335 kref_put(&sfp->f_ref, sg_remove_sfp);
1336 }
1337
1338 /*
1339 * This function is a "bottom half" handler that is called by the mid
1340 * level when a command is completed (or has failed).
1341 */
1342 static void
1343 sg_rq_end_io(struct request *rq, int uptodate)
1344 {
1345 struct sg_request *srp = rq->end_io_data;
1346 Sg_device *sdp;
1347 Sg_fd *sfp;
1348 unsigned long iflags;
1349 unsigned int ms;
1350 char *sense;
1351 int result, resid, done = 1;
1352
1353 if (WARN_ON(srp->done != 0))
1354 return;
1355
1356 sfp = srp->parentfp;
1357 if (WARN_ON(sfp == NULL))
1358 return;
1359
1360 sdp = sfp->parentdp;
1361 if (unlikely(atomic_read(&sdp->detaching)))
1362 pr_info("%s: device detaching\n", __func__);
1363
1364 sense = rq->sense;
1365 result = rq->errors;
1366 resid = rq->resid_len;
1367
1368 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1369 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1370 srp->header.pack_id, result));
1371 srp->header.resid = resid;
1372 ms = jiffies_to_msecs(jiffies);
1373 srp->header.duration = (ms > srp->header.duration) ?
1374 (ms - srp->header.duration) : 0;
1375 if (0 != result) {
1376 struct scsi_sense_hdr sshdr;
1377
1378 srp->header.status = 0xff & result;
1379 srp->header.masked_status = status_byte(result);
1380 srp->header.msg_status = msg_byte(result);
1381 srp->header.host_status = host_byte(result);
1382 srp->header.driver_status = driver_byte(result);
1383 if ((sdp->sgdebug > 0) &&
1384 ((CHECK_CONDITION == srp->header.masked_status) ||
1385 (COMMAND_TERMINATED == srp->header.masked_status)))
1386 __scsi_print_sense(sdp->device, __func__, sense,
1387 SCSI_SENSE_BUFFERSIZE);
1388
1389 /* Following if statement is a patch supplied by Eric Youngdale */
1390 if (driver_byte(result) != 0
1391 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1392 && !scsi_sense_is_deferred(&sshdr)
1393 && sshdr.sense_key == UNIT_ATTENTION
1394 && sdp->device->removable) {
1395 /* Detected possible disc change. Set the bit - this */
1396 /* may be used if there are filesystems using this device */
1397 sdp->device->changed = 1;
1398 }
1399 }
1400 /* Rely on write phase to clean out srp status values, so no "else" */
1401
1402 /*
1403 * Free the request as soon as it is complete so that its resources
1404 * can be reused without waiting for userspace to read() the
1405 * result. But keep the associated bio (if any) around until
1406 * blk_rq_unmap_user() can be called from user context.
1407 */
1408 srp->rq = NULL;
1409 if (rq->cmd != rq->__cmd)
1410 kfree(rq->cmd);
1411 __blk_put_request(rq->q, rq);
1412
1413 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1414 if (unlikely(srp->orphan)) {
1415 if (sfp->keep_orphan)
1416 srp->sg_io_owned = 0;
1417 else
1418 done = 0;
1419 }
1420 srp->done = done;
1421 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1422
1423 if (likely(done)) {
1424 /* Now wake up any sg_read() that is waiting for this
1425 * packet.
1426 */
1427 wake_up_interruptible(&sfp->read_wait);
1428 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1429 kref_put(&sfp->f_ref, sg_remove_sfp);
1430 } else {
1431 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1432 schedule_work(&srp->ew.work);
1433 }
1434 }
1435
1436 static const struct file_operations sg_fops = {
1437 .owner = THIS_MODULE,
1438 .read = sg_read,
1439 .write = sg_write,
1440 .poll = sg_poll,
1441 .unlocked_ioctl = sg_ioctl,
1442 #ifdef CONFIG_COMPAT
1443 .compat_ioctl = sg_compat_ioctl,
1444 #endif
1445 .open = sg_open,
1446 .mmap = sg_mmap,
1447 .release = sg_release,
1448 .fasync = sg_fasync,
1449 .llseek = no_llseek,
1450 };
1451
1452 static struct class *sg_sysfs_class;
1453
1454 static int sg_sysfs_valid = 0;
1455
1456 static Sg_device *
1457 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1458 {
1459 struct request_queue *q = scsidp->request_queue;
1460 Sg_device *sdp;
1461 unsigned long iflags;
1462 int error;
1463 u32 k;
1464
1465 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1466 if (!sdp) {
1467 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1468 "failure\n", __func__);
1469 return ERR_PTR(-ENOMEM);
1470 }
1471
1472 idr_preload(GFP_KERNEL);
1473 write_lock_irqsave(&sg_index_lock, iflags);
1474
1475 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1476 if (error < 0) {
1477 if (error == -ENOSPC) {
1478 sdev_printk(KERN_WARNING, scsidp,
1479 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1480 scsidp->type, SG_MAX_DEVS - 1);
1481 error = -ENODEV;
1482 } else {
1483 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1484 "allocation Sg_device failure: %d\n",
1485 __func__, error);
1486 }
1487 goto out_unlock;
1488 }
1489 k = error;
1490
1491 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1492 "sg_alloc: dev=%d \n", k));
1493 sprintf(disk->disk_name, "sg%d", k);
1494 disk->first_minor = k;
1495 sdp->disk = disk;
1496 sdp->device = scsidp;
1497 mutex_init(&sdp->open_rel_lock);
1498 INIT_LIST_HEAD(&sdp->sfds);
1499 init_waitqueue_head(&sdp->open_wait);
1500 atomic_set(&sdp->detaching, 0);
1501 rwlock_init(&sdp->sfd_lock);
1502 sdp->sg_tablesize = queue_max_segments(q);
1503 sdp->index = k;
1504 kref_init(&sdp->d_ref);
1505 error = 0;
1506
1507 out_unlock:
1508 write_unlock_irqrestore(&sg_index_lock, iflags);
1509 idr_preload_end();
1510
1511 if (error) {
1512 kfree(sdp);
1513 return ERR_PTR(error);
1514 }
1515 return sdp;
1516 }
1517
1518 static int
1519 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1520 {
1521 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1522 struct gendisk *disk;
1523 Sg_device *sdp = NULL;
1524 struct cdev * cdev = NULL;
1525 int error;
1526 unsigned long iflags;
1527
1528 disk = alloc_disk(1);
1529 if (!disk) {
1530 pr_warn("%s: alloc_disk failed\n", __func__);
1531 return -ENOMEM;
1532 }
1533 disk->major = SCSI_GENERIC_MAJOR;
1534
1535 error = -ENOMEM;
1536 cdev = cdev_alloc();
1537 if (!cdev) {
1538 pr_warn("%s: cdev_alloc failed\n", __func__);
1539 goto out;
1540 }
1541 cdev->owner = THIS_MODULE;
1542 cdev->ops = &sg_fops;
1543
1544 sdp = sg_alloc(disk, scsidp);
1545 if (IS_ERR(sdp)) {
1546 pr_warn("%s: sg_alloc failed\n", __func__);
1547 error = PTR_ERR(sdp);
1548 goto out;
1549 }
1550
1551 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1552 if (error)
1553 goto cdev_add_err;
1554
1555 sdp->cdev = cdev;
1556 if (sg_sysfs_valid) {
1557 struct device *sg_class_member;
1558
1559 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1560 MKDEV(SCSI_GENERIC_MAJOR,
1561 sdp->index),
1562 sdp, "%s", disk->disk_name);
1563 if (IS_ERR(sg_class_member)) {
1564 pr_err("%s: device_create failed\n", __func__);
1565 error = PTR_ERR(sg_class_member);
1566 goto cdev_add_err;
1567 }
1568 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1569 &sg_class_member->kobj, "generic");
1570 if (error)
1571 pr_err("%s: unable to make symlink 'generic' back "
1572 "to sg%d\n", __func__, sdp->index);
1573 } else
1574 pr_warn("%s: sg_sys Invalid\n", __func__);
1575
1576 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1577 "type %d\n", sdp->index, scsidp->type);
1578
1579 dev_set_drvdata(cl_dev, sdp);
1580
1581 return 0;
1582
1583 cdev_add_err:
1584 write_lock_irqsave(&sg_index_lock, iflags);
1585 idr_remove(&sg_index_idr, sdp->index);
1586 write_unlock_irqrestore(&sg_index_lock, iflags);
1587 kfree(sdp);
1588
1589 out:
1590 put_disk(disk);
1591 if (cdev)
1592 cdev_del(cdev);
1593 return error;
1594 }
1595
1596 static void
1597 sg_device_destroy(struct kref *kref)
1598 {
1599 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1600 unsigned long flags;
1601
1602 /* CAUTION! Note that the device can still be found via idr_find()
1603 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1604 * any other cleanup.
1605 */
1606
1607 write_lock_irqsave(&sg_index_lock, flags);
1608 idr_remove(&sg_index_idr, sdp->index);
1609 write_unlock_irqrestore(&sg_index_lock, flags);
1610
1611 SCSI_LOG_TIMEOUT(3,
1612 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1613
1614 put_disk(sdp->disk);
1615 kfree(sdp);
1616 }
1617
1618 static void
1619 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1620 {
1621 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1622 Sg_device *sdp = dev_get_drvdata(cl_dev);
1623 unsigned long iflags;
1624 Sg_fd *sfp;
1625 int val;
1626
1627 if (!sdp)
1628 return;
1629 /* want sdp->detaching non-zero as soon as possible */
1630 val = atomic_inc_return(&sdp->detaching);
1631 if (val > 1)
1632 return; /* only want to do following once per device */
1633
1634 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1635 "%s\n", __func__));
1636
1637 read_lock_irqsave(&sdp->sfd_lock, iflags);
1638 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1639 wake_up_interruptible_all(&sfp->read_wait);
1640 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1641 }
1642 wake_up_interruptible_all(&sdp->open_wait);
1643 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1644
1645 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1646 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1647 cdev_del(sdp->cdev);
1648 sdp->cdev = NULL;
1649
1650 kref_put(&sdp->d_ref, sg_device_destroy);
1651 }
1652
1653 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1654 module_param_named(def_reserved_size, def_reserved_size, int,
1655 S_IRUGO | S_IWUSR);
1656 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1657
1658 MODULE_AUTHOR("Douglas Gilbert");
1659 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1660 MODULE_LICENSE("GPL");
1661 MODULE_VERSION(SG_VERSION_STR);
1662 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1663
1664 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1665 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1666 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1667 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1668
1669 static int __init
1670 init_sg(void)
1671 {
1672 int rc;
1673
1674 if (scatter_elem_sz < PAGE_SIZE) {
1675 scatter_elem_sz = PAGE_SIZE;
1676 scatter_elem_sz_prev = scatter_elem_sz;
1677 }
1678 if (def_reserved_size >= 0)
1679 sg_big_buff = def_reserved_size;
1680 else
1681 def_reserved_size = sg_big_buff;
1682
1683 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1684 SG_MAX_DEVS, "sg");
1685 if (rc)
1686 return rc;
1687 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1688 if ( IS_ERR(sg_sysfs_class) ) {
1689 rc = PTR_ERR(sg_sysfs_class);
1690 goto err_out;
1691 }
1692 sg_sysfs_valid = 1;
1693 rc = scsi_register_interface(&sg_interface);
1694 if (0 == rc) {
1695 #ifdef CONFIG_SCSI_PROC_FS
1696 sg_proc_init();
1697 #endif /* CONFIG_SCSI_PROC_FS */
1698 return 0;
1699 }
1700 class_destroy(sg_sysfs_class);
1701 err_out:
1702 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1703 return rc;
1704 }
1705
1706 static void __exit
1707 exit_sg(void)
1708 {
1709 #ifdef CONFIG_SCSI_PROC_FS
1710 sg_proc_cleanup();
1711 #endif /* CONFIG_SCSI_PROC_FS */
1712 scsi_unregister_interface(&sg_interface);
1713 class_destroy(sg_sysfs_class);
1714 sg_sysfs_valid = 0;
1715 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1716 SG_MAX_DEVS);
1717 idr_destroy(&sg_index_idr);
1718 }
1719
1720 static int
1721 sg_start_req(Sg_request *srp, unsigned char *cmd)
1722 {
1723 int res;
1724 struct request *rq;
1725 Sg_fd *sfp = srp->parentfp;
1726 sg_io_hdr_t *hp = &srp->header;
1727 int dxfer_len = (int) hp->dxfer_len;
1728 int dxfer_dir = hp->dxfer_direction;
1729 unsigned int iov_count = hp->iovec_count;
1730 Sg_scatter_hold *req_schp = &srp->data;
1731 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1732 struct request_queue *q = sfp->parentdp->device->request_queue;
1733 struct rq_map_data *md, map_data;
1734 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1735 unsigned char *long_cmdp = NULL;
1736
1737 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1738 "sg_start_req: dxfer_len=%d\n",
1739 dxfer_len));
1740
1741 if (hp->cmd_len > BLK_MAX_CDB) {
1742 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1743 if (!long_cmdp)
1744 return -ENOMEM;
1745 }
1746
1747 /*
1748 * NOTE
1749 *
1750 * With scsi-mq enabled, there are a fixed number of preallocated
1751 * requests equal in number to shost->can_queue. If all of the
1752 * preallocated requests are already in use, then using GFP_ATOMIC with
1753 * blk_get_request() will return -EWOULDBLOCK, whereas using GFP_KERNEL
1754 * will cause blk_get_request() to sleep until an active command
1755 * completes, freeing up a request. Neither option is ideal, but
1756 * GFP_KERNEL is the better choice to prevent userspace from getting an
1757 * unexpected EWOULDBLOCK.
1758 *
1759 * With scsi-mq disabled, blk_get_request() with GFP_KERNEL usually
1760 * does not sleep except under memory pressure.
1761 */
1762 rq = blk_get_request(q, rw, GFP_KERNEL);
1763 if (IS_ERR(rq)) {
1764 kfree(long_cmdp);
1765 return PTR_ERR(rq);
1766 }
1767
1768 blk_rq_set_block_pc(rq);
1769
1770 if (hp->cmd_len > BLK_MAX_CDB)
1771 rq->cmd = long_cmdp;
1772 memcpy(rq->cmd, cmd, hp->cmd_len);
1773 rq->cmd_len = hp->cmd_len;
1774
1775 srp->rq = rq;
1776 rq->end_io_data = srp;
1777 rq->sense = srp->sense_b;
1778 rq->retries = SG_DEFAULT_RETRIES;
1779
1780 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1781 return 0;
1782
1783 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1784 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1785 !sfp->parentdp->device->host->unchecked_isa_dma &&
1786 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1787 md = NULL;
1788 else
1789 md = &map_data;
1790
1791 if (md) {
1792 mutex_lock(&sfp->f_mutex);
1793 if (dxfer_len <= rsv_schp->bufflen &&
1794 !sfp->res_in_use) {
1795 sfp->res_in_use = 1;
1796 sg_link_reserve(sfp, srp, dxfer_len);
1797 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1798 res = -EBUSY; /* sfp->res_in_use == 1 */
1799 if (dxfer_len > rsv_schp->bufflen)
1800 res = -ENOMEM;
1801 mutex_unlock(&sfp->f_mutex);
1802 return res;
1803 } else {
1804 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1805 if (res) {
1806 mutex_unlock(&sfp->f_mutex);
1807 return res;
1808 }
1809 }
1810 mutex_unlock(&sfp->f_mutex);
1811
1812 md->pages = req_schp->pages;
1813 md->page_order = req_schp->page_order;
1814 md->nr_entries = req_schp->k_use_sg;
1815 md->offset = 0;
1816 md->null_mapped = hp->dxferp ? 0 : 1;
1817 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1818 md->from_user = 1;
1819 else
1820 md->from_user = 0;
1821 }
1822
1823 if (iov_count) {
1824 struct iovec *iov = NULL;
1825 struct iov_iter i;
1826
1827 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1828 if (res < 0)
1829 return res;
1830
1831 iov_iter_truncate(&i, hp->dxfer_len);
1832 if (!iov_iter_count(&i)) {
1833 kfree(iov);
1834 return -EINVAL;
1835 }
1836
1837 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1838 kfree(iov);
1839 } else
1840 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1841 hp->dxfer_len, GFP_ATOMIC);
1842
1843 if (!res) {
1844 srp->bio = rq->bio;
1845
1846 if (!md) {
1847 req_schp->dio_in_use = 1;
1848 hp->info |= SG_INFO_DIRECT_IO;
1849 }
1850 }
1851 return res;
1852 }
1853
1854 static int
1855 sg_finish_rem_req(Sg_request *srp)
1856 {
1857 int ret = 0;
1858
1859 Sg_fd *sfp = srp->parentfp;
1860 Sg_scatter_hold *req_schp = &srp->data;
1861
1862 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1863 "sg_finish_rem_req: res_used=%d\n",
1864 (int) srp->res_used));
1865 if (srp->bio)
1866 ret = blk_rq_unmap_user(srp->bio);
1867
1868 if (srp->rq) {
1869 if (srp->rq->cmd != srp->rq->__cmd)
1870 kfree(srp->rq->cmd);
1871 blk_put_request(srp->rq);
1872 }
1873
1874 if (srp->res_used)
1875 sg_unlink_reserve(sfp, srp);
1876 else
1877 sg_remove_scat(sfp, req_schp);
1878
1879 return ret;
1880 }
1881
1882 static int
1883 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1884 {
1885 int sg_bufflen = tablesize * sizeof(struct page *);
1886 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1887
1888 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1889 if (!schp->pages)
1890 return -ENOMEM;
1891 schp->sglist_len = sg_bufflen;
1892 return tablesize; /* number of scat_gath elements allocated */
1893 }
1894
1895 static int
1896 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1897 {
1898 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1899 int sg_tablesize = sfp->parentdp->sg_tablesize;
1900 int blk_size = buff_size, order;
1901 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1902 struct sg_device *sdp = sfp->parentdp;
1903
1904 if (blk_size < 0)
1905 return -EFAULT;
1906 if (0 == blk_size)
1907 ++blk_size; /* don't know why */
1908 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1909 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1910 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1911 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1912 buff_size, blk_size));
1913
1914 /* N.B. ret_sz carried into this block ... */
1915 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1916 if (mx_sc_elems < 0)
1917 return mx_sc_elems; /* most likely -ENOMEM */
1918
1919 num = scatter_elem_sz;
1920 if (unlikely(num != scatter_elem_sz_prev)) {
1921 if (num < PAGE_SIZE) {
1922 scatter_elem_sz = PAGE_SIZE;
1923 scatter_elem_sz_prev = PAGE_SIZE;
1924 } else
1925 scatter_elem_sz_prev = num;
1926 }
1927
1928 if (sdp->device->host->unchecked_isa_dma)
1929 gfp_mask |= GFP_DMA;
1930
1931 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1932 gfp_mask |= __GFP_ZERO;
1933
1934 order = get_order(num);
1935 retry:
1936 ret_sz = 1 << (PAGE_SHIFT + order);
1937
1938 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1939 k++, rem_sz -= ret_sz) {
1940
1941 num = (rem_sz > scatter_elem_sz_prev) ?
1942 scatter_elem_sz_prev : rem_sz;
1943
1944 schp->pages[k] = alloc_pages(gfp_mask | __GFP_ZERO, order);
1945 if (!schp->pages[k])
1946 goto out;
1947
1948 if (num == scatter_elem_sz_prev) {
1949 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1950 scatter_elem_sz = ret_sz;
1951 scatter_elem_sz_prev = ret_sz;
1952 }
1953 }
1954
1955 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1956 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1957 k, num, ret_sz));
1958 } /* end of for loop */
1959
1960 schp->page_order = order;
1961 schp->k_use_sg = k;
1962 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1963 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1964 k, rem_sz));
1965
1966 schp->bufflen = blk_size;
1967 if (rem_sz > 0) /* must have failed */
1968 return -ENOMEM;
1969 return 0;
1970 out:
1971 for (i = 0; i < k; i++)
1972 __free_pages(schp->pages[i], order);
1973
1974 if (--order >= 0)
1975 goto retry;
1976
1977 return -ENOMEM;
1978 }
1979
1980 static void
1981 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1982 {
1983 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1984 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1985 if (schp->pages && schp->sglist_len > 0) {
1986 if (!schp->dio_in_use) {
1987 int k;
1988
1989 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1990 SCSI_LOG_TIMEOUT(5,
1991 sg_printk(KERN_INFO, sfp->parentdp,
1992 "sg_remove_scat: k=%d, pg=0x%p\n",
1993 k, schp->pages[k]));
1994 __free_pages(schp->pages[k], schp->page_order);
1995 }
1996
1997 kfree(schp->pages);
1998 }
1999 }
2000 memset(schp, 0, sizeof (*schp));
2001 }
2002
2003 static int
2004 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2005 {
2006 Sg_scatter_hold *schp = &srp->data;
2007 int k, num;
2008
2009 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2010 "sg_read_oxfer: num_read_xfer=%d\n",
2011 num_read_xfer));
2012 if ((!outp) || (num_read_xfer <= 0))
2013 return 0;
2014
2015 num = 1 << (PAGE_SHIFT + schp->page_order);
2016 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
2017 if (num > num_read_xfer) {
2018 if (__copy_to_user(outp, page_address(schp->pages[k]),
2019 num_read_xfer))
2020 return -EFAULT;
2021 break;
2022 } else {
2023 if (__copy_to_user(outp, page_address(schp->pages[k]),
2024 num))
2025 return -EFAULT;
2026 num_read_xfer -= num;
2027 if (num_read_xfer <= 0)
2028 break;
2029 outp += num;
2030 }
2031 }
2032
2033 return 0;
2034 }
2035
2036 static void
2037 sg_build_reserve(Sg_fd * sfp, int req_size)
2038 {
2039 Sg_scatter_hold *schp = &sfp->reserve;
2040
2041 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2042 "sg_build_reserve: req_size=%d\n", req_size));
2043 do {
2044 if (req_size < PAGE_SIZE)
2045 req_size = PAGE_SIZE;
2046 if (0 == sg_build_indirect(schp, sfp, req_size))
2047 return;
2048 else
2049 sg_remove_scat(sfp, schp);
2050 req_size >>= 1; /* divide by 2 */
2051 } while (req_size > (PAGE_SIZE / 2));
2052 }
2053
2054 static void
2055 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2056 {
2057 Sg_scatter_hold *req_schp = &srp->data;
2058 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2059 int k, num, rem;
2060
2061 srp->res_used = 1;
2062 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2063 "sg_link_reserve: size=%d\n", size));
2064 rem = size;
2065
2066 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2067 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2068 if (rem <= num) {
2069 req_schp->k_use_sg = k + 1;
2070 req_schp->sglist_len = rsv_schp->sglist_len;
2071 req_schp->pages = rsv_schp->pages;
2072
2073 req_schp->bufflen = size;
2074 req_schp->page_order = rsv_schp->page_order;
2075 break;
2076 } else
2077 rem -= num;
2078 }
2079
2080 if (k >= rsv_schp->k_use_sg)
2081 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2082 "sg_link_reserve: BAD size\n"));
2083 }
2084
2085 static void
2086 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2087 {
2088 Sg_scatter_hold *req_schp = &srp->data;
2089
2090 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2091 "sg_unlink_reserve: req->k_use_sg=%d\n",
2092 (int) req_schp->k_use_sg));
2093 req_schp->k_use_sg = 0;
2094 req_schp->bufflen = 0;
2095 req_schp->pages = NULL;
2096 req_schp->page_order = 0;
2097 req_schp->sglist_len = 0;
2098 srp->res_used = 0;
2099 /* Called without mutex lock to avoid deadlock */
2100 sfp->res_in_use = 0;
2101 }
2102
2103 static Sg_request *
2104 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2105 {
2106 Sg_request *resp;
2107 unsigned long iflags;
2108
2109 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2110 list_for_each_entry(resp, &sfp->rq_list, entry) {
2111 /* look for requests that are ready + not SG_IO owned */
2112 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2113 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2114 resp->done = 2; /* guard against other readers */
2115 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2116 return resp;
2117 }
2118 }
2119 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2120 return NULL;
2121 }
2122
2123 /* always adds to end of list */
2124 static Sg_request *
2125 sg_add_request(Sg_fd * sfp)
2126 {
2127 int k;
2128 unsigned long iflags;
2129 Sg_request *rp = sfp->req_arr;
2130
2131 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2132 if (!list_empty(&sfp->rq_list)) {
2133 if (!sfp->cmd_q)
2134 goto out_unlock;
2135
2136 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2137 if (!rp->parentfp)
2138 break;
2139 }
2140 if (k >= SG_MAX_QUEUE)
2141 goto out_unlock;
2142 }
2143 memset(rp, 0, sizeof (Sg_request));
2144 rp->parentfp = sfp;
2145 rp->header.duration = jiffies_to_msecs(jiffies);
2146 list_add_tail(&rp->entry, &sfp->rq_list);
2147 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2148 return rp;
2149 out_unlock:
2150 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2151 return NULL;
2152 }
2153
2154 /* Return of 1 for found; 0 for not found */
2155 static int
2156 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2157 {
2158 unsigned long iflags;
2159 int res = 0;
2160
2161 if (!sfp || !srp || list_empty(&sfp->rq_list))
2162 return res;
2163 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2164 if (!list_empty(&srp->entry)) {
2165 list_del(&srp->entry);
2166 srp->parentfp = NULL;
2167 res = 1;
2168 }
2169 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2170 return res;
2171 }
2172
2173 static Sg_fd *
2174 sg_add_sfp(Sg_device * sdp)
2175 {
2176 Sg_fd *sfp;
2177 unsigned long iflags;
2178 int bufflen;
2179
2180 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2181 if (!sfp)
2182 return ERR_PTR(-ENOMEM);
2183
2184 init_waitqueue_head(&sfp->read_wait);
2185 rwlock_init(&sfp->rq_list_lock);
2186 INIT_LIST_HEAD(&sfp->rq_list);
2187 kref_init(&sfp->f_ref);
2188 mutex_init(&sfp->f_mutex);
2189 sfp->timeout = SG_DEFAULT_TIMEOUT;
2190 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2191 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2192 sfp->cmd_q = SG_DEF_COMMAND_Q;
2193 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2194 sfp->parentdp = sdp;
2195 write_lock_irqsave(&sdp->sfd_lock, iflags);
2196 if (atomic_read(&sdp->detaching)) {
2197 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2198 kfree(sfp);
2199 return ERR_PTR(-ENODEV);
2200 }
2201 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2202 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2203 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2204 "sg_add_sfp: sfp=0x%p\n", sfp));
2205 if (unlikely(sg_big_buff != def_reserved_size))
2206 sg_big_buff = def_reserved_size;
2207
2208 bufflen = min_t(int, sg_big_buff,
2209 max_sectors_bytes(sdp->device->request_queue));
2210 sg_build_reserve(sfp, bufflen);
2211 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2212 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2213 sfp->reserve.bufflen,
2214 sfp->reserve.k_use_sg));
2215
2216 kref_get(&sdp->d_ref);
2217 __module_get(THIS_MODULE);
2218 return sfp;
2219 }
2220
2221 static void
2222 sg_remove_sfp_usercontext(struct work_struct *work)
2223 {
2224 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2225 struct sg_device *sdp = sfp->parentdp;
2226 Sg_request *srp;
2227 unsigned long iflags;
2228
2229 /* Cleanup any responses which were never read(). */
2230 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2231 while (!list_empty(&sfp->rq_list)) {
2232 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2233 sg_finish_rem_req(srp);
2234 list_del(&srp->entry);
2235 srp->parentfp = NULL;
2236 }
2237 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2238
2239 if (sfp->reserve.bufflen > 0) {
2240 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2241 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2242 (int) sfp->reserve.bufflen,
2243 (int) sfp->reserve.k_use_sg));
2244 sg_remove_scat(sfp, &sfp->reserve);
2245 }
2246
2247 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2248 "sg_remove_sfp: sfp=0x%p\n", sfp));
2249 kfree(sfp);
2250
2251 scsi_device_put(sdp->device);
2252 kref_put(&sdp->d_ref, sg_device_destroy);
2253 module_put(THIS_MODULE);
2254 }
2255
2256 static void
2257 sg_remove_sfp(struct kref *kref)
2258 {
2259 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2260 struct sg_device *sdp = sfp->parentdp;
2261 unsigned long iflags;
2262
2263 write_lock_irqsave(&sdp->sfd_lock, iflags);
2264 list_del(&sfp->sfd_siblings);
2265 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2266
2267 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2268 schedule_work(&sfp->ew.work);
2269 }
2270
2271 #ifdef CONFIG_SCSI_PROC_FS
2272 static int
2273 sg_idr_max_id(int id, void *p, void *data)
2274 {
2275 int *k = data;
2276
2277 if (*k < id)
2278 *k = id;
2279
2280 return 0;
2281 }
2282
2283 static int
2284 sg_last_dev(void)
2285 {
2286 int k = -1;
2287 unsigned long iflags;
2288
2289 read_lock_irqsave(&sg_index_lock, iflags);
2290 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2291 read_unlock_irqrestore(&sg_index_lock, iflags);
2292 return k + 1; /* origin 1 */
2293 }
2294 #endif
2295
2296 /* must be called with sg_index_lock held */
2297 static Sg_device *sg_lookup_dev(int dev)
2298 {
2299 return idr_find(&sg_index_idr, dev);
2300 }
2301
2302 static Sg_device *
2303 sg_get_dev(int dev)
2304 {
2305 struct sg_device *sdp;
2306 unsigned long flags;
2307
2308 read_lock_irqsave(&sg_index_lock, flags);
2309 sdp = sg_lookup_dev(dev);
2310 if (!sdp)
2311 sdp = ERR_PTR(-ENXIO);
2312 else if (atomic_read(&sdp->detaching)) {
2313 /* If sdp->detaching, then the refcount may already be 0, in
2314 * which case it would be a bug to do kref_get().
2315 */
2316 sdp = ERR_PTR(-ENODEV);
2317 } else
2318 kref_get(&sdp->d_ref);
2319 read_unlock_irqrestore(&sg_index_lock, flags);
2320
2321 return sdp;
2322 }
2323
2324 #ifdef CONFIG_SCSI_PROC_FS
2325
2326 static struct proc_dir_entry *sg_proc_sgp = NULL;
2327
2328 static char sg_proc_sg_dirname[] = "scsi/sg";
2329
2330 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2331
2332 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2333 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2334 size_t count, loff_t *off);
2335 static const struct file_operations adio_fops = {
2336 .owner = THIS_MODULE,
2337 .open = sg_proc_single_open_adio,
2338 .read = seq_read,
2339 .llseek = seq_lseek,
2340 .write = sg_proc_write_adio,
2341 .release = single_release,
2342 };
2343
2344 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2345 static ssize_t sg_proc_write_dressz(struct file *filp,
2346 const char __user *buffer, size_t count, loff_t *off);
2347 static const struct file_operations dressz_fops = {
2348 .owner = THIS_MODULE,
2349 .open = sg_proc_single_open_dressz,
2350 .read = seq_read,
2351 .llseek = seq_lseek,
2352 .write = sg_proc_write_dressz,
2353 .release = single_release,
2354 };
2355
2356 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2357 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2358 static const struct file_operations version_fops = {
2359 .owner = THIS_MODULE,
2360 .open = sg_proc_single_open_version,
2361 .read = seq_read,
2362 .llseek = seq_lseek,
2363 .release = single_release,
2364 };
2365
2366 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2367 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2368 static const struct file_operations devhdr_fops = {
2369 .owner = THIS_MODULE,
2370 .open = sg_proc_single_open_devhdr,
2371 .read = seq_read,
2372 .llseek = seq_lseek,
2373 .release = single_release,
2374 };
2375
2376 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2377 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2378 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2379 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2380 static void dev_seq_stop(struct seq_file *s, void *v);
2381 static const struct file_operations dev_fops = {
2382 .owner = THIS_MODULE,
2383 .open = sg_proc_open_dev,
2384 .read = seq_read,
2385 .llseek = seq_lseek,
2386 .release = seq_release,
2387 };
2388 static const struct seq_operations dev_seq_ops = {
2389 .start = dev_seq_start,
2390 .next = dev_seq_next,
2391 .stop = dev_seq_stop,
2392 .show = sg_proc_seq_show_dev,
2393 };
2394
2395 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2396 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2397 static const struct file_operations devstrs_fops = {
2398 .owner = THIS_MODULE,
2399 .open = sg_proc_open_devstrs,
2400 .read = seq_read,
2401 .llseek = seq_lseek,
2402 .release = seq_release,
2403 };
2404 static const struct seq_operations devstrs_seq_ops = {
2405 .start = dev_seq_start,
2406 .next = dev_seq_next,
2407 .stop = dev_seq_stop,
2408 .show = sg_proc_seq_show_devstrs,
2409 };
2410
2411 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2412 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2413 static const struct file_operations debug_fops = {
2414 .owner = THIS_MODULE,
2415 .open = sg_proc_open_debug,
2416 .read = seq_read,
2417 .llseek = seq_lseek,
2418 .release = seq_release,
2419 };
2420 static const struct seq_operations debug_seq_ops = {
2421 .start = dev_seq_start,
2422 .next = dev_seq_next,
2423 .stop = dev_seq_stop,
2424 .show = sg_proc_seq_show_debug,
2425 };
2426
2427
2428 struct sg_proc_leaf {
2429 const char * name;
2430 const struct file_operations * fops;
2431 };
2432
2433 static const struct sg_proc_leaf sg_proc_leaf_arr[] = {
2434 {"allow_dio", &adio_fops},
2435 {"debug", &debug_fops},
2436 {"def_reserved_size", &dressz_fops},
2437 {"device_hdr", &devhdr_fops},
2438 {"devices", &dev_fops},
2439 {"device_strs", &devstrs_fops},
2440 {"version", &version_fops}
2441 };
2442
2443 static int
2444 sg_proc_init(void)
2445 {
2446 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2447 int k;
2448
2449 sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2450 if (!sg_proc_sgp)
2451 return 1;
2452 for (k = 0; k < num_leaves; ++k) {
2453 const struct sg_proc_leaf *leaf = &sg_proc_leaf_arr[k];
2454 umode_t mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2455 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2456 }
2457 return 0;
2458 }
2459
2460 static void
2461 sg_proc_cleanup(void)
2462 {
2463 int k;
2464 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2465
2466 if (!sg_proc_sgp)
2467 return;
2468 for (k = 0; k < num_leaves; ++k)
2469 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2470 remove_proc_entry(sg_proc_sg_dirname, NULL);
2471 }
2472
2473
2474 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2475 {
2476 seq_printf(s, "%d\n", *((int *)s->private));
2477 return 0;
2478 }
2479
2480 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2481 {
2482 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2483 }
2484
2485 static ssize_t
2486 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2487 size_t count, loff_t *off)
2488 {
2489 int err;
2490 unsigned long num;
2491
2492 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2493 return -EACCES;
2494 err = kstrtoul_from_user(buffer, count, 0, &num);
2495 if (err)
2496 return err;
2497 sg_allow_dio = num ? 1 : 0;
2498 return count;
2499 }
2500
2501 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2502 {
2503 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2504 }
2505
2506 static ssize_t
2507 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2508 size_t count, loff_t *off)
2509 {
2510 int err;
2511 unsigned long k = ULONG_MAX;
2512
2513 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2514 return -EACCES;
2515
2516 err = kstrtoul_from_user(buffer, count, 0, &k);
2517 if (err)
2518 return err;
2519 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2520 sg_big_buff = k;
2521 return count;
2522 }
2523 return -ERANGE;
2524 }
2525
2526 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2527 {
2528 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2529 sg_version_date);
2530 return 0;
2531 }
2532
2533 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2534 {
2535 return single_open(file, sg_proc_seq_show_version, NULL);
2536 }
2537
2538 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2539 {
2540 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2541 return 0;
2542 }
2543
2544 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2545 {
2546 return single_open(file, sg_proc_seq_show_devhdr, NULL);
2547 }
2548
2549 struct sg_proc_deviter {
2550 loff_t index;
2551 size_t max;
2552 };
2553
2554 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2555 {
2556 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2557
2558 s->private = it;
2559 if (! it)
2560 return NULL;
2561
2562 it->index = *pos;
2563 it->max = sg_last_dev();
2564 if (it->index >= it->max)
2565 return NULL;
2566 return it;
2567 }
2568
2569 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2570 {
2571 struct sg_proc_deviter * it = s->private;
2572
2573 *pos = ++it->index;
2574 return (it->index < it->max) ? it : NULL;
2575 }
2576
2577 static void dev_seq_stop(struct seq_file *s, void *v)
2578 {
2579 kfree(s->private);
2580 }
2581
2582 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2583 {
2584 return seq_open(file, &dev_seq_ops);
2585 }
2586
2587 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2588 {
2589 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2590 Sg_device *sdp;
2591 struct scsi_device *scsidp;
2592 unsigned long iflags;
2593
2594 read_lock_irqsave(&sg_index_lock, iflags);
2595 sdp = it ? sg_lookup_dev(it->index) : NULL;
2596 if ((NULL == sdp) || (NULL == sdp->device) ||
2597 (atomic_read(&sdp->detaching)))
2598 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2599 else {
2600 scsidp = sdp->device;
2601 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2602 scsidp->host->host_no, scsidp->channel,
2603 scsidp->id, scsidp->lun, (int) scsidp->type,
2604 1,
2605 (int) scsidp->queue_depth,
2606 (int) atomic_read(&scsidp->device_busy),
2607 (int) scsi_device_online(scsidp));
2608 }
2609 read_unlock_irqrestore(&sg_index_lock, iflags);
2610 return 0;
2611 }
2612
2613 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2614 {
2615 return seq_open(file, &devstrs_seq_ops);
2616 }
2617
2618 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2619 {
2620 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2621 Sg_device *sdp;
2622 struct scsi_device *scsidp;
2623 unsigned long iflags;
2624
2625 read_lock_irqsave(&sg_index_lock, iflags);
2626 sdp = it ? sg_lookup_dev(it->index) : NULL;
2627 scsidp = sdp ? sdp->device : NULL;
2628 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2629 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2630 scsidp->vendor, scsidp->model, scsidp->rev);
2631 else
2632 seq_puts(s, "<no active device>\n");
2633 read_unlock_irqrestore(&sg_index_lock, iflags);
2634 return 0;
2635 }
2636
2637 /* must be called while holding sg_index_lock */
2638 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2639 {
2640 int k, new_interface, blen, usg;
2641 Sg_request *srp;
2642 Sg_fd *fp;
2643 const sg_io_hdr_t *hp;
2644 const char * cp;
2645 unsigned int ms;
2646
2647 k = 0;
2648 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2649 k++;
2650 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2651 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2652 "(res)sgat=%d low_dma=%d\n", k,
2653 jiffies_to_msecs(fp->timeout),
2654 fp->reserve.bufflen,
2655 (int) fp->reserve.k_use_sg,
2656 (int) sdp->device->host->unchecked_isa_dma);
2657 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2658 (int) fp->cmd_q, (int) fp->force_packid,
2659 (int) fp->keep_orphan);
2660 list_for_each_entry(srp, &fp->rq_list, entry) {
2661 hp = &srp->header;
2662 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2663 if (srp->res_used) {
2664 if (new_interface &&
2665 (SG_FLAG_MMAP_IO & hp->flags))
2666 cp = " mmap>> ";
2667 else
2668 cp = " rb>> ";
2669 } else {
2670 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2671 cp = " dio>> ";
2672 else
2673 cp = " ";
2674 }
2675 seq_puts(s, cp);
2676 blen = srp->data.bufflen;
2677 usg = srp->data.k_use_sg;
2678 seq_puts(s, srp->done ?
2679 ((1 == srp->done) ? "rcv:" : "fin:")
2680 : "act:");
2681 seq_printf(s, " id=%d blen=%d",
2682 srp->header.pack_id, blen);
2683 if (srp->done)
2684 seq_printf(s, " dur=%d", hp->duration);
2685 else {
2686 ms = jiffies_to_msecs(jiffies);
2687 seq_printf(s, " t_o/elap=%d/%d",
2688 (new_interface ? hp->timeout :
2689 jiffies_to_msecs(fp->timeout)),
2690 (ms > hp->duration ? ms - hp->duration : 0));
2691 }
2692 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2693 (int) srp->data.cmd_opcode);
2694 }
2695 if (list_empty(&fp->rq_list))
2696 seq_puts(s, " No requests active\n");
2697 read_unlock(&fp->rq_list_lock);
2698 }
2699 }
2700
2701 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2702 {
2703 return seq_open(file, &debug_seq_ops);
2704 }
2705
2706 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2707 {
2708 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2709 Sg_device *sdp;
2710 unsigned long iflags;
2711
2712 if (it && (0 == it->index))
2713 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2714 (int)it->max, sg_big_buff);
2715
2716 read_lock_irqsave(&sg_index_lock, iflags);
2717 sdp = it ? sg_lookup_dev(it->index) : NULL;
2718 if (NULL == sdp)
2719 goto skip;
2720 read_lock(&sdp->sfd_lock);
2721 if (!list_empty(&sdp->sfds)) {
2722 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2723 if (atomic_read(&sdp->detaching))
2724 seq_puts(s, "detaching pending close ");
2725 else if (sdp->device) {
2726 struct scsi_device *scsidp = sdp->device;
2727
2728 seq_printf(s, "%d:%d:%d:%llu em=%d",
2729 scsidp->host->host_no,
2730 scsidp->channel, scsidp->id,
2731 scsidp->lun,
2732 scsidp->host->hostt->emulated);
2733 }
2734 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2735 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2736 sg_proc_debug_helper(s, sdp);
2737 }
2738 read_unlock(&sdp->sfd_lock);
2739 skip:
2740 read_unlock_irqrestore(&sg_index_lock, iflags);
2741 return 0;
2742 }
2743
2744 #endif /* CONFIG_SCSI_PROC_FS */
2745
2746 module_init(init_sg);
2747 module_exit(exit_sg);
Linux with added FPC-III support