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1 /*
2 * History:
3 * Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
4 * to allow user process control of SCSI devices.
5 * Development Sponsored by Killy Corp. NY NY
6 *
7 * Original driver (sg.c):
8 * Copyright (C) 1992 Lawrence Foard
9 * Version 2 and 3 extensions to driver:
10 * Copyright (C) 1998 - 2014 Douglas Gilbert
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2, or (at your option)
15 * any later version.
16 *
17 */
18
19 static int sg_version_num = 30536; /* 2 digits for each component */
20 #define SG_VERSION_STR "3.5.36"
21
22 /*
23 * D. P. Gilbert (dgilbert@interlog.com), notes:
24 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
25 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING
26 * (otherwise the macros compile to empty statements).
27 *
28 */
29 #include <linux/module.h>
30
31 #include <linux/fs.h>
32 #include <linux/kernel.h>
33 #include <linux/sched.h>
34 #include <linux/string.h>
35 #include <linux/mm.h>
36 #include <linux/errno.h>
37 #include <linux/mtio.h>
38 #include <linux/ioctl.h>
39 #include <linux/slab.h>
40 #include <linux/fcntl.h>
41 #include <linux/init.h>
42 #include <linux/poll.h>
43 #include <linux/moduleparam.h>
44 #include <linux/cdev.h>
45 #include <linux/idr.h>
46 #include <linux/seq_file.h>
47 #include <linux/blkdev.h>
48 #include <linux/delay.h>
49 #include <linux/blktrace_api.h>
50 #include <linux/mutex.h>
51 #include <linux/atomic.h>
52 #include <linux/ratelimit.h>
53 #include <linux/uio.h>
54 #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 #define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
84
85 int sg_big_buff = SG_DEF_RESERVED_SIZE;
86 /* N.B. This variable is readable and writeable via
87 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
88 of this size (or less if there is not enough memory) will be reserved
89 for use by this file descriptor. [Deprecated usage: this variable is also
90 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
91 the kernel (i.e. it is not a module).] */
92 static int def_reserved_size = -1; /* picks up init parameter */
93 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
94
95 static int scatter_elem_sz = SG_SCATTER_SZ;
96 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
97
98 #define SG_SECTOR_SZ 512
99
100 static int sg_add_device(struct device *, struct class_interface *);
101 static void sg_remove_device(struct device *, struct class_interface *);
102
103 static DEFINE_IDR(sg_index_idr);
104 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
105 file descriptor list for device */
106
107 static struct class_interface sg_interface = {
108 .add_dev = sg_add_device,
109 .remove_dev = sg_remove_device,
110 };
111
112 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
113 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
114 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
115 unsigned bufflen; /* Size of (aggregate) data buffer */
116 struct page **pages;
117 int page_order;
118 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
119 unsigned char cmd_opcode; /* first byte of command */
120 } Sg_scatter_hold;
121
122 struct sg_device; /* forward declarations */
123 struct sg_fd;
124
125 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
126 struct list_head entry; /* list entry */
127 struct sg_fd *parentfp; /* NULL -> not in use */
128 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
129 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
130 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
131 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
132 char orphan; /* 1 -> drop on sight, 0 -> normal */
133 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
134 /* done protected by rq_list_lock */
135 char done; /* 0->before bh, 1->before read, 2->read */
136 struct request *rq;
137 struct bio *bio;
138 struct execute_work ew;
139 } Sg_request;
140
141 typedef struct sg_fd { /* holds the state of a file descriptor */
142 struct list_head sfd_siblings; /* protected by device's sfd_lock */
143 struct sg_device *parentdp; /* owning device */
144 wait_queue_head_t read_wait; /* queue read until command done */
145 rwlock_t rq_list_lock; /* protect access to list in req_arr */
146 struct mutex f_mutex; /* protect against changes in this fd */
147 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
148 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
149 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
150 struct list_head rq_list; /* head of request list */
151 struct fasync_struct *async_qp; /* used by asynchronous notification */
152 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
153 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
154 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
155 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
156 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
157 char mmap_called; /* 0 -> mmap() never called on this fd */
158 char res_in_use; /* 1 -> 'reserve' array in use */
159 struct kref f_ref;
160 struct execute_work ew;
161 } Sg_fd;
162
163 typedef struct sg_device { /* holds the state of each scsi generic device */
164 struct scsi_device *device;
165 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */
166 struct mutex open_rel_lock; /* held when in open() or release() */
167 int sg_tablesize; /* adapter's max scatter-gather table size */
168 u32 index; /* device index number */
169 struct list_head sfds;
170 rwlock_t sfd_lock; /* protect access to sfd list */
171 atomic_t detaching; /* 0->device usable, 1->device detaching */
172 bool exclude; /* 1->open(O_EXCL) succeeded and is active */
173 int open_cnt; /* count of opens (perhaps < num(sfds) ) */
174 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
175 struct gendisk *disk;
176 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
177 struct kref d_ref;
178 } Sg_device;
179
180 /* tasklet or soft irq callback */
181 static void sg_rq_end_io(struct request *rq, blk_status_t status);
182 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
183 static int sg_finish_rem_req(Sg_request * srp);
184 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
185 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
186 Sg_request * srp);
187 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
188 const char __user *buf, size_t count, int blocking,
189 int read_only, int sg_io_owned, Sg_request **o_srp);
190 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
191 unsigned char *cmnd, int timeout, int blocking);
192 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
193 static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
194 static void sg_build_reserve(Sg_fd * sfp, int req_size);
195 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
196 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
197 static Sg_fd *sg_add_sfp(Sg_device * sdp);
198 static void sg_remove_sfp(struct kref *);
199 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
200 static Sg_request *sg_add_request(Sg_fd * sfp);
201 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
202 static Sg_device *sg_get_dev(int dev);
203 static void sg_device_destroy(struct kref *kref);
204
205 #define SZ_SG_HEADER sizeof(struct sg_header)
206 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
207 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
208 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
209
210 #define sg_printk(prefix, sdp, fmt, a...) \
211 sdev_prefix_printk(prefix, (sdp)->device, \
212 (sdp)->disk->disk_name, fmt, ##a)
213
214 /*
215 * The SCSI interfaces that use read() and write() as an asynchronous variant of
216 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways
217 * to trigger read() and write() calls from various contexts with elevated
218 * privileges. This can lead to kernel memory corruption (e.g. if these
219 * interfaces are called through splice()) and privilege escalation inside
220 * userspace (e.g. if a process with access to such a device passes a file
221 * descriptor to a SUID binary as stdin/stdout/stderr).
222 *
223 * This function provides protection for the legacy API by restricting the
224 * calling context.
225 */
226 static int sg_check_file_access(struct file *filp, const char *caller)
227 {
228 if (filp->f_cred != current_real_cred()) {
229 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
230 caller, task_tgid_vnr(current), current->comm);
231 return -EPERM;
232 }
233 if (uaccess_kernel()) {
234 pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n",
235 caller, task_tgid_vnr(current), current->comm);
236 return -EACCES;
237 }
238 return 0;
239 }
240
241 static int sg_allow_access(struct file *filp, unsigned char *cmd)
242 {
243 struct sg_fd *sfp = filp->private_data;
244
245 if (sfp->parentdp->device->type == TYPE_SCANNER)
246 return 0;
247
248 return blk_verify_command(cmd, filp->f_mode);
249 }
250
251 static int
252 open_wait(Sg_device *sdp, int flags)
253 {
254 int retval = 0;
255
256 if (flags & O_EXCL) {
257 while (sdp->open_cnt > 0) {
258 mutex_unlock(&sdp->open_rel_lock);
259 retval = wait_event_interruptible(sdp->open_wait,
260 (atomic_read(&sdp->detaching) ||
261 !sdp->open_cnt));
262 mutex_lock(&sdp->open_rel_lock);
263
264 if (retval) /* -ERESTARTSYS */
265 return retval;
266 if (atomic_read(&sdp->detaching))
267 return -ENODEV;
268 }
269 } else {
270 while (sdp->exclude) {
271 mutex_unlock(&sdp->open_rel_lock);
272 retval = wait_event_interruptible(sdp->open_wait,
273 (atomic_read(&sdp->detaching) ||
274 !sdp->exclude));
275 mutex_lock(&sdp->open_rel_lock);
276
277 if (retval) /* -ERESTARTSYS */
278 return retval;
279 if (atomic_read(&sdp->detaching))
280 return -ENODEV;
281 }
282 }
283
284 return retval;
285 }
286
287 /* Returns 0 on success, else a negated errno value */
288 static int
289 sg_open(struct inode *inode, struct file *filp)
290 {
291 int dev = iminor(inode);
292 int flags = filp->f_flags;
293 struct request_queue *q;
294 Sg_device *sdp;
295 Sg_fd *sfp;
296 int retval;
297
298 nonseekable_open(inode, filp);
299 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
300 return -EPERM; /* Can't lock it with read only access */
301 sdp = sg_get_dev(dev);
302 if (IS_ERR(sdp))
303 return PTR_ERR(sdp);
304
305 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
306 "sg_open: flags=0x%x\n", flags));
307
308 /* This driver's module count bumped by fops_get in <linux/fs.h> */
309 /* Prevent the device driver from vanishing while we sleep */
310 retval = scsi_device_get(sdp->device);
311 if (retval)
312 goto sg_put;
313
314 retval = scsi_autopm_get_device(sdp->device);
315 if (retval)
316 goto sdp_put;
317
318 /* scsi_block_when_processing_errors() may block so bypass
319 * check if O_NONBLOCK. Permits SCSI commands to be issued
320 * during error recovery. Tread carefully. */
321 if (!((flags & O_NONBLOCK) ||
322 scsi_block_when_processing_errors(sdp->device))) {
323 retval = -ENXIO;
324 /* we are in error recovery for this device */
325 goto error_out;
326 }
327
328 mutex_lock(&sdp->open_rel_lock);
329 if (flags & O_NONBLOCK) {
330 if (flags & O_EXCL) {
331 if (sdp->open_cnt > 0) {
332 retval = -EBUSY;
333 goto error_mutex_locked;
334 }
335 } else {
336 if (sdp->exclude) {
337 retval = -EBUSY;
338 goto error_mutex_locked;
339 }
340 }
341 } else {
342 retval = open_wait(sdp, flags);
343 if (retval) /* -ERESTARTSYS or -ENODEV */
344 goto error_mutex_locked;
345 }
346
347 /* N.B. at this point we are holding the open_rel_lock */
348 if (flags & O_EXCL)
349 sdp->exclude = true;
350
351 if (sdp->open_cnt < 1) { /* no existing opens */
352 sdp->sgdebug = 0;
353 q = sdp->device->request_queue;
354 sdp->sg_tablesize = queue_max_segments(q);
355 }
356 sfp = sg_add_sfp(sdp);
357 if (IS_ERR(sfp)) {
358 retval = PTR_ERR(sfp);
359 goto out_undo;
360 }
361
362 filp->private_data = sfp;
363 sdp->open_cnt++;
364 mutex_unlock(&sdp->open_rel_lock);
365
366 retval = 0;
367 sg_put:
368 kref_put(&sdp->d_ref, sg_device_destroy);
369 return retval;
370
371 out_undo:
372 if (flags & O_EXCL) {
373 sdp->exclude = false; /* undo if error */
374 wake_up_interruptible(&sdp->open_wait);
375 }
376 error_mutex_locked:
377 mutex_unlock(&sdp->open_rel_lock);
378 error_out:
379 scsi_autopm_put_device(sdp->device);
380 sdp_put:
381 scsi_device_put(sdp->device);
382 goto sg_put;
383 }
384
385 /* Release resources associated with a successful sg_open()
386 * Returns 0 on success, else a negated errno value */
387 static int
388 sg_release(struct inode *inode, struct file *filp)
389 {
390 Sg_device *sdp;
391 Sg_fd *sfp;
392
393 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
394 return -ENXIO;
395 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
396
397 mutex_lock(&sdp->open_rel_lock);
398 scsi_autopm_put_device(sdp->device);
399 kref_put(&sfp->f_ref, sg_remove_sfp);
400 sdp->open_cnt--;
401
402 /* possibly many open()s waiting on exlude clearing, start many;
403 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
404 if (sdp->exclude) {
405 sdp->exclude = false;
406 wake_up_interruptible_all(&sdp->open_wait);
407 } else if (0 == sdp->open_cnt) {
408 wake_up_interruptible(&sdp->open_wait);
409 }
410 mutex_unlock(&sdp->open_rel_lock);
411 return 0;
412 }
413
414 static ssize_t
415 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
416 {
417 Sg_device *sdp;
418 Sg_fd *sfp;
419 Sg_request *srp;
420 int req_pack_id = -1;
421 sg_io_hdr_t *hp;
422 struct sg_header *old_hdr = NULL;
423 int retval = 0;
424
425 /*
426 * This could cause a response to be stranded. Close the associated
427 * file descriptor to free up any resources being held.
428 */
429 retval = sg_check_file_access(filp, __func__);
430 if (retval)
431 return retval;
432
433 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
434 return -ENXIO;
435 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
436 "sg_read: count=%d\n", (int) count));
437
438 if (!access_ok(VERIFY_WRITE, buf, count))
439 return -EFAULT;
440 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
441 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
442 if (!old_hdr)
443 return -ENOMEM;
444 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
445 retval = -EFAULT;
446 goto free_old_hdr;
447 }
448 if (old_hdr->reply_len < 0) {
449 if (count >= SZ_SG_IO_HDR) {
450 sg_io_hdr_t *new_hdr;
451 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
452 if (!new_hdr) {
453 retval = -ENOMEM;
454 goto free_old_hdr;
455 }
456 retval =__copy_from_user
457 (new_hdr, buf, SZ_SG_IO_HDR);
458 req_pack_id = new_hdr->pack_id;
459 kfree(new_hdr);
460 if (retval) {
461 retval = -EFAULT;
462 goto free_old_hdr;
463 }
464 }
465 } else
466 req_pack_id = old_hdr->pack_id;
467 }
468 srp = sg_get_rq_mark(sfp, req_pack_id);
469 if (!srp) { /* now wait on packet to arrive */
470 if (atomic_read(&sdp->detaching)) {
471 retval = -ENODEV;
472 goto free_old_hdr;
473 }
474 if (filp->f_flags & O_NONBLOCK) {
475 retval = -EAGAIN;
476 goto free_old_hdr;
477 }
478 retval = wait_event_interruptible(sfp->read_wait,
479 (atomic_read(&sdp->detaching) ||
480 (srp = sg_get_rq_mark(sfp, req_pack_id))));
481 if (atomic_read(&sdp->detaching)) {
482 retval = -ENODEV;
483 goto free_old_hdr;
484 }
485 if (retval) {
486 /* -ERESTARTSYS as signal hit process */
487 goto free_old_hdr;
488 }
489 }
490 if (srp->header.interface_id != '\0') {
491 retval = sg_new_read(sfp, buf, count, srp);
492 goto free_old_hdr;
493 }
494
495 hp = &srp->header;
496 if (old_hdr == NULL) {
497 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
498 if (! old_hdr) {
499 retval = -ENOMEM;
500 goto free_old_hdr;
501 }
502 }
503 memset(old_hdr, 0, SZ_SG_HEADER);
504 old_hdr->reply_len = (int) hp->timeout;
505 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
506 old_hdr->pack_id = hp->pack_id;
507 old_hdr->twelve_byte =
508 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
509 old_hdr->target_status = hp->masked_status;
510 old_hdr->host_status = hp->host_status;
511 old_hdr->driver_status = hp->driver_status;
512 if ((CHECK_CONDITION & hp->masked_status) ||
513 (DRIVER_SENSE & hp->driver_status))
514 memcpy(old_hdr->sense_buffer, srp->sense_b,
515 sizeof (old_hdr->sense_buffer));
516 switch (hp->host_status) {
517 /* This setup of 'result' is for backward compatibility and is best
518 ignored by the user who should use target, host + driver status */
519 case DID_OK:
520 case DID_PASSTHROUGH:
521 case DID_SOFT_ERROR:
522 old_hdr->result = 0;
523 break;
524 case DID_NO_CONNECT:
525 case DID_BUS_BUSY:
526 case DID_TIME_OUT:
527 old_hdr->result = EBUSY;
528 break;
529 case DID_BAD_TARGET:
530 case DID_ABORT:
531 case DID_PARITY:
532 case DID_RESET:
533 case DID_BAD_INTR:
534 old_hdr->result = EIO;
535 break;
536 case DID_ERROR:
537 old_hdr->result = (srp->sense_b[0] == 0 &&
538 hp->masked_status == GOOD) ? 0 : EIO;
539 break;
540 default:
541 old_hdr->result = EIO;
542 break;
543 }
544
545 /* Now copy the result back to the user buffer. */
546 if (count >= SZ_SG_HEADER) {
547 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
548 retval = -EFAULT;
549 goto free_old_hdr;
550 }
551 buf += SZ_SG_HEADER;
552 if (count > old_hdr->reply_len)
553 count = old_hdr->reply_len;
554 if (count > SZ_SG_HEADER) {
555 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
556 retval = -EFAULT;
557 goto free_old_hdr;
558 }
559 }
560 } else
561 count = (old_hdr->result == 0) ? 0 : -EIO;
562 sg_finish_rem_req(srp);
563 sg_remove_request(sfp, srp);
564 retval = count;
565 free_old_hdr:
566 kfree(old_hdr);
567 return retval;
568 }
569
570 static ssize_t
571 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
572 {
573 sg_io_hdr_t *hp = &srp->header;
574 int err = 0, err2;
575 int len;
576
577 if (count < SZ_SG_IO_HDR) {
578 err = -EINVAL;
579 goto err_out;
580 }
581 hp->sb_len_wr = 0;
582 if ((hp->mx_sb_len > 0) && hp->sbp) {
583 if ((CHECK_CONDITION & hp->masked_status) ||
584 (DRIVER_SENSE & hp->driver_status)) {
585 int sb_len = SCSI_SENSE_BUFFERSIZE;
586 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
587 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
588 len = (len > sb_len) ? sb_len : len;
589 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
590 err = -EFAULT;
591 goto err_out;
592 }
593 hp->sb_len_wr = len;
594 }
595 }
596 if (hp->masked_status || hp->host_status || hp->driver_status)
597 hp->info |= SG_INFO_CHECK;
598 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
599 err = -EFAULT;
600 goto err_out;
601 }
602 err_out:
603 err2 = sg_finish_rem_req(srp);
604 sg_remove_request(sfp, srp);
605 return err ? : err2 ? : count;
606 }
607
608 static ssize_t
609 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
610 {
611 int mxsize, cmd_size, k;
612 int input_size, blocking;
613 unsigned char opcode;
614 Sg_device *sdp;
615 Sg_fd *sfp;
616 Sg_request *srp;
617 struct sg_header old_hdr;
618 sg_io_hdr_t *hp;
619 unsigned char cmnd[SG_MAX_CDB_SIZE];
620 int retval;
621
622 retval = sg_check_file_access(filp, __func__);
623 if (retval)
624 return retval;
625
626 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
627 return -ENXIO;
628 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
629 "sg_write: count=%d\n", (int) count));
630 if (atomic_read(&sdp->detaching))
631 return -ENODEV;
632 if (!((filp->f_flags & O_NONBLOCK) ||
633 scsi_block_when_processing_errors(sdp->device)))
634 return -ENXIO;
635
636 if (!access_ok(VERIFY_READ, buf, count))
637 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
638 if (count < SZ_SG_HEADER)
639 return -EIO;
640 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
641 return -EFAULT;
642 blocking = !(filp->f_flags & O_NONBLOCK);
643 if (old_hdr.reply_len < 0)
644 return sg_new_write(sfp, filp, buf, count,
645 blocking, 0, 0, NULL);
646 if (count < (SZ_SG_HEADER + 6))
647 return -EIO; /* The minimum scsi command length is 6 bytes. */
648
649 if (!(srp = sg_add_request(sfp))) {
650 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
651 "sg_write: queue full\n"));
652 return -EDOM;
653 }
654 buf += SZ_SG_HEADER;
655 __get_user(opcode, buf);
656 mutex_lock(&sfp->f_mutex);
657 if (sfp->next_cmd_len > 0) {
658 cmd_size = sfp->next_cmd_len;
659 sfp->next_cmd_len = 0; /* reset so only this write() effected */
660 } else {
661 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
662 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
663 cmd_size = 12;
664 }
665 mutex_unlock(&sfp->f_mutex);
666 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
667 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
668 /* Determine buffer size. */
669 input_size = count - cmd_size;
670 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
671 mxsize -= SZ_SG_HEADER;
672 input_size -= SZ_SG_HEADER;
673 if (input_size < 0) {
674 sg_remove_request(sfp, srp);
675 return -EIO; /* User did not pass enough bytes for this command. */
676 }
677 hp = &srp->header;
678 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
679 hp->cmd_len = (unsigned char) cmd_size;
680 hp->iovec_count = 0;
681 hp->mx_sb_len = 0;
682 if (input_size > 0)
683 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
684 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
685 else
686 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
687 hp->dxfer_len = mxsize;
688 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
689 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
690 hp->dxferp = (char __user *)buf + cmd_size;
691 else
692 hp->dxferp = NULL;
693 hp->sbp = NULL;
694 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
695 hp->flags = input_size; /* structure abuse ... */
696 hp->pack_id = old_hdr.pack_id;
697 hp->usr_ptr = NULL;
698 if (__copy_from_user(cmnd, buf, cmd_size))
699 return -EFAULT;
700 /*
701 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
702 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
703 * is a non-zero input_size, so emit a warning.
704 */
705 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
706 printk_ratelimited(KERN_WARNING
707 "sg_write: data in/out %d/%d bytes "
708 "for SCSI command 0x%x-- guessing "
709 "data in;\n program %s not setting "
710 "count and/or reply_len properly\n",
711 old_hdr.reply_len - (int)SZ_SG_HEADER,
712 input_size, (unsigned int) cmnd[0],
713 current->comm);
714 }
715 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
716 return (k < 0) ? k : count;
717 }
718
719 static ssize_t
720 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
721 size_t count, int blocking, int read_only, int sg_io_owned,
722 Sg_request **o_srp)
723 {
724 int k;
725 Sg_request *srp;
726 sg_io_hdr_t *hp;
727 unsigned char cmnd[SG_MAX_CDB_SIZE];
728 int timeout;
729 unsigned long ul_timeout;
730
731 if (count < SZ_SG_IO_HDR)
732 return -EINVAL;
733 if (!access_ok(VERIFY_READ, buf, count))
734 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
735
736 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
737 if (!(srp = sg_add_request(sfp))) {
738 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
739 "sg_new_write: queue full\n"));
740 return -EDOM;
741 }
742 srp->sg_io_owned = sg_io_owned;
743 hp = &srp->header;
744 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
745 sg_remove_request(sfp, srp);
746 return -EFAULT;
747 }
748 if (hp->interface_id != 'S') {
749 sg_remove_request(sfp, srp);
750 return -ENOSYS;
751 }
752 if (hp->flags & SG_FLAG_MMAP_IO) {
753 if (hp->dxfer_len > sfp->reserve.bufflen) {
754 sg_remove_request(sfp, srp);
755 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
756 }
757 if (hp->flags & SG_FLAG_DIRECT_IO) {
758 sg_remove_request(sfp, srp);
759 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
760 }
761 if (sfp->res_in_use) {
762 sg_remove_request(sfp, srp);
763 return -EBUSY; /* reserve buffer already being used */
764 }
765 }
766 ul_timeout = msecs_to_jiffies(srp->header.timeout);
767 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
768 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
769 sg_remove_request(sfp, srp);
770 return -EMSGSIZE;
771 }
772 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
773 sg_remove_request(sfp, srp);
774 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
775 }
776 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
777 sg_remove_request(sfp, srp);
778 return -EFAULT;
779 }
780 if (read_only && sg_allow_access(file, cmnd)) {
781 sg_remove_request(sfp, srp);
782 return -EPERM;
783 }
784 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
785 if (k < 0)
786 return k;
787 if (o_srp)
788 *o_srp = srp;
789 return count;
790 }
791
792 static int
793 sg_common_write(Sg_fd * sfp, Sg_request * srp,
794 unsigned char *cmnd, int timeout, int blocking)
795 {
796 int k, at_head;
797 Sg_device *sdp = sfp->parentdp;
798 sg_io_hdr_t *hp = &srp->header;
799
800 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
801 hp->status = 0;
802 hp->masked_status = 0;
803 hp->msg_status = 0;
804 hp->info = 0;
805 hp->host_status = 0;
806 hp->driver_status = 0;
807 hp->resid = 0;
808 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
809 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
810 (int) cmnd[0], (int) hp->cmd_len));
811
812 if (hp->dxfer_len >= SZ_256M)
813 return -EINVAL;
814
815 k = sg_start_req(srp, cmnd);
816 if (k) {
817 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
818 "sg_common_write: start_req err=%d\n", k));
819 sg_finish_rem_req(srp);
820 sg_remove_request(sfp, srp);
821 return k; /* probably out of space --> ENOMEM */
822 }
823 if (atomic_read(&sdp->detaching)) {
824 if (srp->bio) {
825 scsi_req_free_cmd(scsi_req(srp->rq));
826 blk_end_request_all(srp->rq, BLK_STS_IOERR);
827 srp->rq = NULL;
828 }
829
830 sg_finish_rem_req(srp);
831 sg_remove_request(sfp, srp);
832 return -ENODEV;
833 }
834
835 hp->duration = jiffies_to_msecs(jiffies);
836 if (hp->interface_id != '\0' && /* v3 (or later) interface */
837 (SG_FLAG_Q_AT_TAIL & hp->flags))
838 at_head = 0;
839 else
840 at_head = 1;
841
842 srp->rq->timeout = timeout;
843 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
844 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
845 srp->rq, at_head, sg_rq_end_io);
846 return 0;
847 }
848
849 static int srp_done(Sg_fd *sfp, Sg_request *srp)
850 {
851 unsigned long flags;
852 int ret;
853
854 read_lock_irqsave(&sfp->rq_list_lock, flags);
855 ret = srp->done;
856 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
857 return ret;
858 }
859
860 static int max_sectors_bytes(struct request_queue *q)
861 {
862 unsigned int max_sectors = queue_max_sectors(q);
863
864 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
865
866 return max_sectors << 9;
867 }
868
869 static void
870 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
871 {
872 Sg_request *srp;
873 int val;
874 unsigned int ms;
875
876 val = 0;
877 list_for_each_entry(srp, &sfp->rq_list, entry) {
878 if (val >= SG_MAX_QUEUE)
879 break;
880 rinfo[val].req_state = srp->done + 1;
881 rinfo[val].problem =
882 srp->header.masked_status &
883 srp->header.host_status &
884 srp->header.driver_status;
885 if (srp->done)
886 rinfo[val].duration =
887 srp->header.duration;
888 else {
889 ms = jiffies_to_msecs(jiffies);
890 rinfo[val].duration =
891 (ms > srp->header.duration) ?
892 (ms - srp->header.duration) : 0;
893 }
894 rinfo[val].orphan = srp->orphan;
895 rinfo[val].sg_io_owned = srp->sg_io_owned;
896 rinfo[val].pack_id = srp->header.pack_id;
897 rinfo[val].usr_ptr = srp->header.usr_ptr;
898 val++;
899 }
900 }
901
902 static long
903 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
904 {
905 void __user *p = (void __user *)arg;
906 int __user *ip = p;
907 int result, val, read_only;
908 Sg_device *sdp;
909 Sg_fd *sfp;
910 Sg_request *srp;
911 unsigned long iflags;
912
913 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
914 return -ENXIO;
915
916 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
917 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
918 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
919
920 switch (cmd_in) {
921 case SG_IO:
922 if (atomic_read(&sdp->detaching))
923 return -ENODEV;
924 if (!scsi_block_when_processing_errors(sdp->device))
925 return -ENXIO;
926 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
927 return -EFAULT;
928 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
929 1, read_only, 1, &srp);
930 if (result < 0)
931 return result;
932 result = wait_event_interruptible(sfp->read_wait,
933 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
934 if (atomic_read(&sdp->detaching))
935 return -ENODEV;
936 write_lock_irq(&sfp->rq_list_lock);
937 if (srp->done) {
938 srp->done = 2;
939 write_unlock_irq(&sfp->rq_list_lock);
940 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
941 return (result < 0) ? result : 0;
942 }
943 srp->orphan = 1;
944 write_unlock_irq(&sfp->rq_list_lock);
945 return result; /* -ERESTARTSYS because signal hit process */
946 case SG_SET_TIMEOUT:
947 result = get_user(val, ip);
948 if (result)
949 return result;
950 if (val < 0)
951 return -EIO;
952 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
953 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
954 INT_MAX);
955 sfp->timeout_user = val;
956 sfp->timeout = mult_frac(val, HZ, USER_HZ);
957
958 return 0;
959 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
960 /* strange ..., for backward compatibility */
961 return sfp->timeout_user;
962 case SG_SET_FORCE_LOW_DMA:
963 /*
964 * N.B. This ioctl never worked properly, but failed to
965 * return an error value. So returning '0' to keep compability
966 * with legacy applications.
967 */
968 return 0;
969 case SG_GET_LOW_DMA:
970 return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
971 case SG_GET_SCSI_ID:
972 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
973 return -EFAULT;
974 else {
975 sg_scsi_id_t __user *sg_idp = p;
976
977 if (atomic_read(&sdp->detaching))
978 return -ENODEV;
979 __put_user((int) sdp->device->host->host_no,
980 &sg_idp->host_no);
981 __put_user((int) sdp->device->channel,
982 &sg_idp->channel);
983 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
984 __put_user((int) sdp->device->lun, &sg_idp->lun);
985 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
986 __put_user((short) sdp->device->host->cmd_per_lun,
987 &sg_idp->h_cmd_per_lun);
988 __put_user((short) sdp->device->queue_depth,
989 &sg_idp->d_queue_depth);
990 __put_user(0, &sg_idp->unused[0]);
991 __put_user(0, &sg_idp->unused[1]);
992 return 0;
993 }
994 case SG_SET_FORCE_PACK_ID:
995 result = get_user(val, ip);
996 if (result)
997 return result;
998 sfp->force_packid = val ? 1 : 0;
999 return 0;
1000 case SG_GET_PACK_ID:
1001 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
1002 return -EFAULT;
1003 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1004 list_for_each_entry(srp, &sfp->rq_list, entry) {
1005 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1006 read_unlock_irqrestore(&sfp->rq_list_lock,
1007 iflags);
1008 __put_user(srp->header.pack_id, ip);
1009 return 0;
1010 }
1011 }
1012 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1013 __put_user(-1, ip);
1014 return 0;
1015 case SG_GET_NUM_WAITING:
1016 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1017 val = 0;
1018 list_for_each_entry(srp, &sfp->rq_list, entry) {
1019 if ((1 == srp->done) && (!srp->sg_io_owned))
1020 ++val;
1021 }
1022 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1023 return put_user(val, ip);
1024 case SG_GET_SG_TABLESIZE:
1025 return put_user(sdp->sg_tablesize, ip);
1026 case SG_SET_RESERVED_SIZE:
1027 result = get_user(val, ip);
1028 if (result)
1029 return result;
1030 if (val < 0)
1031 return -EINVAL;
1032 val = min_t(int, val,
1033 max_sectors_bytes(sdp->device->request_queue));
1034 mutex_lock(&sfp->f_mutex);
1035 if (val != sfp->reserve.bufflen) {
1036 if (sfp->mmap_called ||
1037 sfp->res_in_use) {
1038 mutex_unlock(&sfp->f_mutex);
1039 return -EBUSY;
1040 }
1041
1042 sg_remove_scat(sfp, &sfp->reserve);
1043 sg_build_reserve(sfp, val);
1044 }
1045 mutex_unlock(&sfp->f_mutex);
1046 return 0;
1047 case SG_GET_RESERVED_SIZE:
1048 val = min_t(int, sfp->reserve.bufflen,
1049 max_sectors_bytes(sdp->device->request_queue));
1050 return put_user(val, ip);
1051 case SG_SET_COMMAND_Q:
1052 result = get_user(val, ip);
1053 if (result)
1054 return result;
1055 sfp->cmd_q = val ? 1 : 0;
1056 return 0;
1057 case SG_GET_COMMAND_Q:
1058 return put_user((int) sfp->cmd_q, ip);
1059 case SG_SET_KEEP_ORPHAN:
1060 result = get_user(val, ip);
1061 if (result)
1062 return result;
1063 sfp->keep_orphan = val;
1064 return 0;
1065 case SG_GET_KEEP_ORPHAN:
1066 return put_user((int) sfp->keep_orphan, ip);
1067 case SG_NEXT_CMD_LEN:
1068 result = get_user(val, ip);
1069 if (result)
1070 return result;
1071 if (val > SG_MAX_CDB_SIZE)
1072 return -ENOMEM;
1073 sfp->next_cmd_len = (val > 0) ? val : 0;
1074 return 0;
1075 case SG_GET_VERSION_NUM:
1076 return put_user(sg_version_num, ip);
1077 case SG_GET_ACCESS_COUNT:
1078 /* faked - we don't have a real access count anymore */
1079 val = (sdp->device ? 1 : 0);
1080 return put_user(val, ip);
1081 case SG_GET_REQUEST_TABLE:
1082 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
1083 return -EFAULT;
1084 else {
1085 sg_req_info_t *rinfo;
1086
1087 rinfo = kzalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
1088 GFP_KERNEL);
1089 if (!rinfo)
1090 return -ENOMEM;
1091 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1092 sg_fill_request_table(sfp, rinfo);
1093 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1094 result = __copy_to_user(p, rinfo,
1095 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1096 result = result ? -EFAULT : 0;
1097 kfree(rinfo);
1098 return result;
1099 }
1100 case SG_EMULATED_HOST:
1101 if (atomic_read(&sdp->detaching))
1102 return -ENODEV;
1103 return put_user(sdp->device->host->hostt->emulated, ip);
1104 case SCSI_IOCTL_SEND_COMMAND:
1105 if (atomic_read(&sdp->detaching))
1106 return -ENODEV;
1107 if (read_only) {
1108 unsigned char opcode = WRITE_6;
1109 Scsi_Ioctl_Command __user *siocp = p;
1110
1111 if (copy_from_user(&opcode, siocp->data, 1))
1112 return -EFAULT;
1113 if (sg_allow_access(filp, &opcode))
1114 return -EPERM;
1115 }
1116 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1117 case SG_SET_DEBUG:
1118 result = get_user(val, ip);
1119 if (result)
1120 return result;
1121 sdp->sgdebug = (char) val;
1122 return 0;
1123 case BLKSECTGET:
1124 return put_user(max_sectors_bytes(sdp->device->request_queue),
1125 ip);
1126 case BLKTRACESETUP:
1127 return blk_trace_setup(sdp->device->request_queue,
1128 sdp->disk->disk_name,
1129 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1130 NULL, p);
1131 case BLKTRACESTART:
1132 return blk_trace_startstop(sdp->device->request_queue, 1);
1133 case BLKTRACESTOP:
1134 return blk_trace_startstop(sdp->device->request_queue, 0);
1135 case BLKTRACETEARDOWN:
1136 return blk_trace_remove(sdp->device->request_queue);
1137 case SCSI_IOCTL_GET_IDLUN:
1138 case SCSI_IOCTL_GET_BUS_NUMBER:
1139 case SCSI_IOCTL_PROBE_HOST:
1140 case SG_GET_TRANSFORM:
1141 case SG_SCSI_RESET:
1142 if (atomic_read(&sdp->detaching))
1143 return -ENODEV;
1144 break;
1145 default:
1146 if (read_only)
1147 return -EPERM; /* don't know so take safe approach */
1148 break;
1149 }
1150
1151 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1152 cmd_in, filp->f_flags & O_NDELAY);
1153 if (result)
1154 return result;
1155 return scsi_ioctl(sdp->device, cmd_in, p);
1156 }
1157
1158 #ifdef CONFIG_COMPAT
1159 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1160 {
1161 Sg_device *sdp;
1162 Sg_fd *sfp;
1163 struct scsi_device *sdev;
1164
1165 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1166 return -ENXIO;
1167
1168 sdev = sdp->device;
1169 if (sdev->host->hostt->compat_ioctl) {
1170 int ret;
1171
1172 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1173
1174 return ret;
1175 }
1176
1177 return -ENOIOCTLCMD;
1178 }
1179 #endif
1180
1181 static unsigned int
1182 sg_poll(struct file *filp, poll_table * wait)
1183 {
1184 unsigned int res = 0;
1185 Sg_device *sdp;
1186 Sg_fd *sfp;
1187 Sg_request *srp;
1188 int count = 0;
1189 unsigned long iflags;
1190
1191 sfp = filp->private_data;
1192 if (!sfp)
1193 return POLLERR;
1194 sdp = sfp->parentdp;
1195 if (!sdp)
1196 return POLLERR;
1197 poll_wait(filp, &sfp->read_wait, wait);
1198 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1199 list_for_each_entry(srp, &sfp->rq_list, entry) {
1200 /* if any read waiting, flag it */
1201 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1202 res = POLLIN | POLLRDNORM;
1203 ++count;
1204 }
1205 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1206
1207 if (atomic_read(&sdp->detaching))
1208 res |= POLLHUP;
1209 else if (!sfp->cmd_q) {
1210 if (0 == count)
1211 res |= POLLOUT | POLLWRNORM;
1212 } else if (count < SG_MAX_QUEUE)
1213 res |= POLLOUT | POLLWRNORM;
1214 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1215 "sg_poll: res=0x%x\n", (int) res));
1216 return res;
1217 }
1218
1219 static int
1220 sg_fasync(int fd, struct file *filp, int mode)
1221 {
1222 Sg_device *sdp;
1223 Sg_fd *sfp;
1224
1225 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1226 return -ENXIO;
1227 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1228 "sg_fasync: mode=%d\n", mode));
1229
1230 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1231 }
1232
1233 static int
1234 sg_vma_fault(struct vm_fault *vmf)
1235 {
1236 struct vm_area_struct *vma = vmf->vma;
1237 Sg_fd *sfp;
1238 unsigned long offset, len, sa;
1239 Sg_scatter_hold *rsv_schp;
1240 int k, length;
1241
1242 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1243 return VM_FAULT_SIGBUS;
1244 rsv_schp = &sfp->reserve;
1245 offset = vmf->pgoff << PAGE_SHIFT;
1246 if (offset >= rsv_schp->bufflen)
1247 return VM_FAULT_SIGBUS;
1248 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1249 "sg_vma_fault: offset=%lu, scatg=%d\n",
1250 offset, rsv_schp->k_use_sg));
1251 sa = vma->vm_start;
1252 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1253 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1254 len = vma->vm_end - sa;
1255 len = (len < length) ? len : length;
1256 if (offset < len) {
1257 struct page *page = nth_page(rsv_schp->pages[k],
1258 offset >> PAGE_SHIFT);
1259 get_page(page); /* increment page count */
1260 vmf->page = page;
1261 return 0; /* success */
1262 }
1263 sa += len;
1264 offset -= len;
1265 }
1266
1267 return VM_FAULT_SIGBUS;
1268 }
1269
1270 static const struct vm_operations_struct sg_mmap_vm_ops = {
1271 .fault = sg_vma_fault,
1272 };
1273
1274 static int
1275 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1276 {
1277 Sg_fd *sfp;
1278 unsigned long req_sz, len, sa;
1279 Sg_scatter_hold *rsv_schp;
1280 int k, length;
1281 int ret = 0;
1282
1283 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1284 return -ENXIO;
1285 req_sz = vma->vm_end - vma->vm_start;
1286 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1287 "sg_mmap starting, vm_start=%p, len=%d\n",
1288 (void *) vma->vm_start, (int) req_sz));
1289 if (vma->vm_pgoff)
1290 return -EINVAL; /* want no offset */
1291 rsv_schp = &sfp->reserve;
1292 mutex_lock(&sfp->f_mutex);
1293 if (req_sz > rsv_schp->bufflen) {
1294 ret = -ENOMEM; /* cannot map more than reserved buffer */
1295 goto out;
1296 }
1297
1298 sa = vma->vm_start;
1299 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1300 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1301 len = vma->vm_end - sa;
1302 len = (len < length) ? len : length;
1303 sa += len;
1304 }
1305
1306 sfp->mmap_called = 1;
1307 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1308 vma->vm_private_data = sfp;
1309 vma->vm_ops = &sg_mmap_vm_ops;
1310 out:
1311 mutex_unlock(&sfp->f_mutex);
1312 return ret;
1313 }
1314
1315 static void
1316 sg_rq_end_io_usercontext(struct work_struct *work)
1317 {
1318 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1319 struct sg_fd *sfp = srp->parentfp;
1320
1321 sg_finish_rem_req(srp);
1322 sg_remove_request(sfp, srp);
1323 kref_put(&sfp->f_ref, sg_remove_sfp);
1324 }
1325
1326 /*
1327 * This function is a "bottom half" handler that is called by the mid
1328 * level when a command is completed (or has failed).
1329 */
1330 static void
1331 sg_rq_end_io(struct request *rq, blk_status_t status)
1332 {
1333 struct sg_request *srp = rq->end_io_data;
1334 struct scsi_request *req = scsi_req(rq);
1335 Sg_device *sdp;
1336 Sg_fd *sfp;
1337 unsigned long iflags;
1338 unsigned int ms;
1339 char *sense;
1340 int result, resid, done = 1;
1341
1342 if (WARN_ON(srp->done != 0))
1343 return;
1344
1345 sfp = srp->parentfp;
1346 if (WARN_ON(sfp == NULL))
1347 return;
1348
1349 sdp = sfp->parentdp;
1350 if (unlikely(atomic_read(&sdp->detaching)))
1351 pr_info("%s: device detaching\n", __func__);
1352
1353 sense = req->sense;
1354 result = req->result;
1355 resid = req->resid_len;
1356
1357 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1358 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1359 srp->header.pack_id, result));
1360 srp->header.resid = resid;
1361 ms = jiffies_to_msecs(jiffies);
1362 srp->header.duration = (ms > srp->header.duration) ?
1363 (ms - srp->header.duration) : 0;
1364 if (0 != result) {
1365 struct scsi_sense_hdr sshdr;
1366
1367 srp->header.status = 0xff & result;
1368 srp->header.masked_status = status_byte(result);
1369 srp->header.msg_status = msg_byte(result);
1370 srp->header.host_status = host_byte(result);
1371 srp->header.driver_status = driver_byte(result);
1372 if ((sdp->sgdebug > 0) &&
1373 ((CHECK_CONDITION == srp->header.masked_status) ||
1374 (COMMAND_TERMINATED == srp->header.masked_status)))
1375 __scsi_print_sense(sdp->device, __func__, sense,
1376 SCSI_SENSE_BUFFERSIZE);
1377
1378 /* Following if statement is a patch supplied by Eric Youngdale */
1379 if (driver_byte(result) != 0
1380 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1381 && !scsi_sense_is_deferred(&sshdr)
1382 && sshdr.sense_key == UNIT_ATTENTION
1383 && sdp->device->removable) {
1384 /* Detected possible disc change. Set the bit - this */
1385 /* may be used if there are filesystems using this device */
1386 sdp->device->changed = 1;
1387 }
1388 }
1389
1390 if (req->sense_len)
1391 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1392
1393 /* Rely on write phase to clean out srp status values, so no "else" */
1394
1395 /*
1396 * Free the request as soon as it is complete so that its resources
1397 * can be reused without waiting for userspace to read() the
1398 * result. But keep the associated bio (if any) around until
1399 * blk_rq_unmap_user() can be called from user context.
1400 */
1401 srp->rq = NULL;
1402 scsi_req_free_cmd(scsi_req(rq));
1403 __blk_put_request(rq->q, rq);
1404
1405 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1406 if (unlikely(srp->orphan)) {
1407 if (sfp->keep_orphan)
1408 srp->sg_io_owned = 0;
1409 else
1410 done = 0;
1411 }
1412 srp->done = done;
1413 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1414
1415 if (likely(done)) {
1416 /* Now wake up any sg_read() that is waiting for this
1417 * packet.
1418 */
1419 wake_up_interruptible(&sfp->read_wait);
1420 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1421 kref_put(&sfp->f_ref, sg_remove_sfp);
1422 } else {
1423 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1424 schedule_work(&srp->ew.work);
1425 }
1426 }
1427
1428 static const struct file_operations sg_fops = {
1429 .owner = THIS_MODULE,
1430 .read = sg_read,
1431 .write = sg_write,
1432 .poll = sg_poll,
1433 .unlocked_ioctl = sg_ioctl,
1434 #ifdef CONFIG_COMPAT
1435 .compat_ioctl = sg_compat_ioctl,
1436 #endif
1437 .open = sg_open,
1438 .mmap = sg_mmap,
1439 .release = sg_release,
1440 .fasync = sg_fasync,
1441 .llseek = no_llseek,
1442 };
1443
1444 static struct class *sg_sysfs_class;
1445
1446 static int sg_sysfs_valid = 0;
1447
1448 static Sg_device *
1449 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1450 {
1451 struct request_queue *q = scsidp->request_queue;
1452 Sg_device *sdp;
1453 unsigned long iflags;
1454 int error;
1455 u32 k;
1456
1457 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1458 if (!sdp) {
1459 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1460 "failure\n", __func__);
1461 return ERR_PTR(-ENOMEM);
1462 }
1463
1464 idr_preload(GFP_KERNEL);
1465 write_lock_irqsave(&sg_index_lock, iflags);
1466
1467 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1468 if (error < 0) {
1469 if (error == -ENOSPC) {
1470 sdev_printk(KERN_WARNING, scsidp,
1471 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1472 scsidp->type, SG_MAX_DEVS - 1);
1473 error = -ENODEV;
1474 } else {
1475 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1476 "allocation Sg_device failure: %d\n",
1477 __func__, error);
1478 }
1479 goto out_unlock;
1480 }
1481 k = error;
1482
1483 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1484 "sg_alloc: dev=%d \n", k));
1485 sprintf(disk->disk_name, "sg%d", k);
1486 disk->first_minor = k;
1487 sdp->disk = disk;
1488 sdp->device = scsidp;
1489 mutex_init(&sdp->open_rel_lock);
1490 INIT_LIST_HEAD(&sdp->sfds);
1491 init_waitqueue_head(&sdp->open_wait);
1492 atomic_set(&sdp->detaching, 0);
1493 rwlock_init(&sdp->sfd_lock);
1494 sdp->sg_tablesize = queue_max_segments(q);
1495 sdp->index = k;
1496 kref_init(&sdp->d_ref);
1497 error = 0;
1498
1499 out_unlock:
1500 write_unlock_irqrestore(&sg_index_lock, iflags);
1501 idr_preload_end();
1502
1503 if (error) {
1504 kfree(sdp);
1505 return ERR_PTR(error);
1506 }
1507 return sdp;
1508 }
1509
1510 static int
1511 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1512 {
1513 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1514 struct gendisk *disk;
1515 Sg_device *sdp = NULL;
1516 struct cdev * cdev = NULL;
1517 int error;
1518 unsigned long iflags;
1519
1520 disk = alloc_disk(1);
1521 if (!disk) {
1522 pr_warn("%s: alloc_disk failed\n", __func__);
1523 return -ENOMEM;
1524 }
1525 disk->major = SCSI_GENERIC_MAJOR;
1526
1527 error = -ENOMEM;
1528 cdev = cdev_alloc();
1529 if (!cdev) {
1530 pr_warn("%s: cdev_alloc failed\n", __func__);
1531 goto out;
1532 }
1533 cdev->owner = THIS_MODULE;
1534 cdev->ops = &sg_fops;
1535
1536 sdp = sg_alloc(disk, scsidp);
1537 if (IS_ERR(sdp)) {
1538 pr_warn("%s: sg_alloc failed\n", __func__);
1539 error = PTR_ERR(sdp);
1540 goto out;
1541 }
1542
1543 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1544 if (error)
1545 goto cdev_add_err;
1546
1547 sdp->cdev = cdev;
1548 if (sg_sysfs_valid) {
1549 struct device *sg_class_member;
1550
1551 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1552 MKDEV(SCSI_GENERIC_MAJOR,
1553 sdp->index),
1554 sdp, "%s", disk->disk_name);
1555 if (IS_ERR(sg_class_member)) {
1556 pr_err("%s: device_create failed\n", __func__);
1557 error = PTR_ERR(sg_class_member);
1558 goto cdev_add_err;
1559 }
1560 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1561 &sg_class_member->kobj, "generic");
1562 if (error)
1563 pr_err("%s: unable to make symlink 'generic' back "
1564 "to sg%d\n", __func__, sdp->index);
1565 } else
1566 pr_warn("%s: sg_sys Invalid\n", __func__);
1567
1568 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1569 "type %d\n", sdp->index, scsidp->type);
1570
1571 dev_set_drvdata(cl_dev, sdp);
1572
1573 return 0;
1574
1575 cdev_add_err:
1576 write_lock_irqsave(&sg_index_lock, iflags);
1577 idr_remove(&sg_index_idr, sdp->index);
1578 write_unlock_irqrestore(&sg_index_lock, iflags);
1579 kfree(sdp);
1580
1581 out:
1582 put_disk(disk);
1583 if (cdev)
1584 cdev_del(cdev);
1585 return error;
1586 }
1587
1588 static void
1589 sg_device_destroy(struct kref *kref)
1590 {
1591 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1592 unsigned long flags;
1593
1594 /* CAUTION! Note that the device can still be found via idr_find()
1595 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1596 * any other cleanup.
1597 */
1598
1599 write_lock_irqsave(&sg_index_lock, flags);
1600 idr_remove(&sg_index_idr, sdp->index);
1601 write_unlock_irqrestore(&sg_index_lock, flags);
1602
1603 SCSI_LOG_TIMEOUT(3,
1604 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1605
1606 put_disk(sdp->disk);
1607 kfree(sdp);
1608 }
1609
1610 static void
1611 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1612 {
1613 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1614 Sg_device *sdp = dev_get_drvdata(cl_dev);
1615 unsigned long iflags;
1616 Sg_fd *sfp;
1617 int val;
1618
1619 if (!sdp)
1620 return;
1621 /* want sdp->detaching non-zero as soon as possible */
1622 val = atomic_inc_return(&sdp->detaching);
1623 if (val > 1)
1624 return; /* only want to do following once per device */
1625
1626 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1627 "%s\n", __func__));
1628
1629 read_lock_irqsave(&sdp->sfd_lock, iflags);
1630 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1631 wake_up_interruptible_all(&sfp->read_wait);
1632 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1633 }
1634 wake_up_interruptible_all(&sdp->open_wait);
1635 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1636
1637 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1638 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1639 cdev_del(sdp->cdev);
1640 sdp->cdev = NULL;
1641
1642 kref_put(&sdp->d_ref, sg_device_destroy);
1643 }
1644
1645 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1646 module_param_named(def_reserved_size, def_reserved_size, int,
1647 S_IRUGO | S_IWUSR);
1648 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1649
1650 MODULE_AUTHOR("Douglas Gilbert");
1651 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1652 MODULE_LICENSE("GPL");
1653 MODULE_VERSION(SG_VERSION_STR);
1654 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1655
1656 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1657 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1658 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1659 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1660
1661 static int __init
1662 init_sg(void)
1663 {
1664 int rc;
1665
1666 if (scatter_elem_sz < PAGE_SIZE) {
1667 scatter_elem_sz = PAGE_SIZE;
1668 scatter_elem_sz_prev = scatter_elem_sz;
1669 }
1670 if (def_reserved_size >= 0)
1671 sg_big_buff = def_reserved_size;
1672 else
1673 def_reserved_size = sg_big_buff;
1674
1675 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1676 SG_MAX_DEVS, "sg");
1677 if (rc)
1678 return rc;
1679 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1680 if ( IS_ERR(sg_sysfs_class) ) {
1681 rc = PTR_ERR(sg_sysfs_class);
1682 goto err_out;
1683 }
1684 sg_sysfs_valid = 1;
1685 rc = scsi_register_interface(&sg_interface);
1686 if (0 == rc) {
1687 #ifdef CONFIG_SCSI_PROC_FS
1688 sg_proc_init();
1689 #endif /* CONFIG_SCSI_PROC_FS */
1690 return 0;
1691 }
1692 class_destroy(sg_sysfs_class);
1693 err_out:
1694 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1695 return rc;
1696 }
1697
1698 static void __exit
1699 exit_sg(void)
1700 {
1701 #ifdef CONFIG_SCSI_PROC_FS
1702 sg_proc_cleanup();
1703 #endif /* CONFIG_SCSI_PROC_FS */
1704 scsi_unregister_interface(&sg_interface);
1705 class_destroy(sg_sysfs_class);
1706 sg_sysfs_valid = 0;
1707 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1708 SG_MAX_DEVS);
1709 idr_destroy(&sg_index_idr);
1710 }
1711
1712 static int
1713 sg_start_req(Sg_request *srp, unsigned char *cmd)
1714 {
1715 int res;
1716 struct request *rq;
1717 struct scsi_request *req;
1718 Sg_fd *sfp = srp->parentfp;
1719 sg_io_hdr_t *hp = &srp->header;
1720 int dxfer_len = (int) hp->dxfer_len;
1721 int dxfer_dir = hp->dxfer_direction;
1722 unsigned int iov_count = hp->iovec_count;
1723 Sg_scatter_hold *req_schp = &srp->data;
1724 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1725 struct request_queue *q = sfp->parentdp->device->request_queue;
1726 struct rq_map_data *md, map_data;
1727 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1728 unsigned char *long_cmdp = NULL;
1729
1730 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1731 "sg_start_req: dxfer_len=%d\n",
1732 dxfer_len));
1733
1734 if (hp->cmd_len > BLK_MAX_CDB) {
1735 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1736 if (!long_cmdp)
1737 return -ENOMEM;
1738 }
1739
1740 /*
1741 * NOTE
1742 *
1743 * With scsi-mq enabled, there are a fixed number of preallocated
1744 * requests equal in number to shost->can_queue. If all of the
1745 * preallocated requests are already in use, then using GFP_ATOMIC with
1746 * blk_get_request() will return -EWOULDBLOCK, whereas using GFP_KERNEL
1747 * will cause blk_get_request() to sleep until an active command
1748 * completes, freeing up a request. Neither option is ideal, but
1749 * GFP_KERNEL is the better choice to prevent userspace from getting an
1750 * unexpected EWOULDBLOCK.
1751 *
1752 * With scsi-mq disabled, blk_get_request() with GFP_KERNEL usually
1753 * does not sleep except under memory pressure.
1754 */
1755 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1756 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, GFP_KERNEL);
1757 if (IS_ERR(rq)) {
1758 kfree(long_cmdp);
1759 return PTR_ERR(rq);
1760 }
1761 req = scsi_req(rq);
1762
1763 if (hp->cmd_len > BLK_MAX_CDB)
1764 req->cmd = long_cmdp;
1765 memcpy(req->cmd, cmd, hp->cmd_len);
1766 req->cmd_len = hp->cmd_len;
1767
1768 srp->rq = rq;
1769 rq->end_io_data = srp;
1770 req->retries = SG_DEFAULT_RETRIES;
1771
1772 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1773 return 0;
1774
1775 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1776 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1777 !sfp->parentdp->device->host->unchecked_isa_dma &&
1778 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1779 md = NULL;
1780 else
1781 md = &map_data;
1782
1783 if (md) {
1784 mutex_lock(&sfp->f_mutex);
1785 if (dxfer_len <= rsv_schp->bufflen &&
1786 !sfp->res_in_use) {
1787 sfp->res_in_use = 1;
1788 sg_link_reserve(sfp, srp, dxfer_len);
1789 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1790 res = -EBUSY; /* sfp->res_in_use == 1 */
1791 if (dxfer_len > rsv_schp->bufflen)
1792 res = -ENOMEM;
1793 mutex_unlock(&sfp->f_mutex);
1794 return res;
1795 } else {
1796 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1797 if (res) {
1798 mutex_unlock(&sfp->f_mutex);
1799 return res;
1800 }
1801 }
1802 mutex_unlock(&sfp->f_mutex);
1803
1804 md->pages = req_schp->pages;
1805 md->page_order = req_schp->page_order;
1806 md->nr_entries = req_schp->k_use_sg;
1807 md->offset = 0;
1808 md->null_mapped = hp->dxferp ? 0 : 1;
1809 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1810 md->from_user = 1;
1811 else
1812 md->from_user = 0;
1813 }
1814
1815 if (iov_count) {
1816 struct iovec *iov = NULL;
1817 struct iov_iter i;
1818
1819 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1820 if (res < 0)
1821 return res;
1822
1823 iov_iter_truncate(&i, hp->dxfer_len);
1824 if (!iov_iter_count(&i)) {
1825 kfree(iov);
1826 return -EINVAL;
1827 }
1828
1829 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1830 kfree(iov);
1831 } else
1832 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1833 hp->dxfer_len, GFP_ATOMIC);
1834
1835 if (!res) {
1836 srp->bio = rq->bio;
1837
1838 if (!md) {
1839 req_schp->dio_in_use = 1;
1840 hp->info |= SG_INFO_DIRECT_IO;
1841 }
1842 }
1843 return res;
1844 }
1845
1846 static int
1847 sg_finish_rem_req(Sg_request *srp)
1848 {
1849 int ret = 0;
1850
1851 Sg_fd *sfp = srp->parentfp;
1852 Sg_scatter_hold *req_schp = &srp->data;
1853
1854 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1855 "sg_finish_rem_req: res_used=%d\n",
1856 (int) srp->res_used));
1857 if (srp->bio)
1858 ret = blk_rq_unmap_user(srp->bio);
1859
1860 if (srp->rq) {
1861 scsi_req_free_cmd(scsi_req(srp->rq));
1862 blk_put_request(srp->rq);
1863 }
1864
1865 if (srp->res_used)
1866 sg_unlink_reserve(sfp, srp);
1867 else
1868 sg_remove_scat(sfp, req_schp);
1869
1870 return ret;
1871 }
1872
1873 static int
1874 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1875 {
1876 int sg_bufflen = tablesize * sizeof(struct page *);
1877 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1878
1879 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1880 if (!schp->pages)
1881 return -ENOMEM;
1882 schp->sglist_len = sg_bufflen;
1883 return tablesize; /* number of scat_gath elements allocated */
1884 }
1885
1886 static int
1887 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1888 {
1889 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1890 int sg_tablesize = sfp->parentdp->sg_tablesize;
1891 int blk_size = buff_size, order;
1892 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1893 struct sg_device *sdp = sfp->parentdp;
1894
1895 if (blk_size < 0)
1896 return -EFAULT;
1897 if (0 == blk_size)
1898 ++blk_size; /* don't know why */
1899 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1900 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1901 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1902 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1903 buff_size, blk_size));
1904
1905 /* N.B. ret_sz carried into this block ... */
1906 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1907 if (mx_sc_elems < 0)
1908 return mx_sc_elems; /* most likely -ENOMEM */
1909
1910 num = scatter_elem_sz;
1911 if (unlikely(num != scatter_elem_sz_prev)) {
1912 if (num < PAGE_SIZE) {
1913 scatter_elem_sz = PAGE_SIZE;
1914 scatter_elem_sz_prev = PAGE_SIZE;
1915 } else
1916 scatter_elem_sz_prev = num;
1917 }
1918
1919 if (sdp->device->host->unchecked_isa_dma)
1920 gfp_mask |= GFP_DMA;
1921
1922 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1923 gfp_mask |= __GFP_ZERO;
1924
1925 order = get_order(num);
1926 retry:
1927 ret_sz = 1 << (PAGE_SHIFT + order);
1928
1929 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1930 k++, rem_sz -= ret_sz) {
1931
1932 num = (rem_sz > scatter_elem_sz_prev) ?
1933 scatter_elem_sz_prev : rem_sz;
1934
1935 schp->pages[k] = alloc_pages(gfp_mask | __GFP_ZERO, order);
1936 if (!schp->pages[k])
1937 goto out;
1938
1939 if (num == scatter_elem_sz_prev) {
1940 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1941 scatter_elem_sz = ret_sz;
1942 scatter_elem_sz_prev = ret_sz;
1943 }
1944 }
1945
1946 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1947 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1948 k, num, ret_sz));
1949 } /* end of for loop */
1950
1951 schp->page_order = order;
1952 schp->k_use_sg = k;
1953 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1954 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1955 k, rem_sz));
1956
1957 schp->bufflen = blk_size;
1958 if (rem_sz > 0) /* must have failed */
1959 return -ENOMEM;
1960 return 0;
1961 out:
1962 for (i = 0; i < k; i++)
1963 __free_pages(schp->pages[i], order);
1964
1965 if (--order >= 0)
1966 goto retry;
1967
1968 return -ENOMEM;
1969 }
1970
1971 static void
1972 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1973 {
1974 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1975 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1976 if (schp->pages && schp->sglist_len > 0) {
1977 if (!schp->dio_in_use) {
1978 int k;
1979
1980 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1981 SCSI_LOG_TIMEOUT(5,
1982 sg_printk(KERN_INFO, sfp->parentdp,
1983 "sg_remove_scat: k=%d, pg=0x%p\n",
1984 k, schp->pages[k]));
1985 __free_pages(schp->pages[k], schp->page_order);
1986 }
1987
1988 kfree(schp->pages);
1989 }
1990 }
1991 memset(schp, 0, sizeof (*schp));
1992 }
1993
1994 static int
1995 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1996 {
1997 Sg_scatter_hold *schp = &srp->data;
1998 int k, num;
1999
2000 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2001 "sg_read_oxfer: num_read_xfer=%d\n",
2002 num_read_xfer));
2003 if ((!outp) || (num_read_xfer <= 0))
2004 return 0;
2005
2006 num = 1 << (PAGE_SHIFT + schp->page_order);
2007 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
2008 if (num > num_read_xfer) {
2009 if (__copy_to_user(outp, page_address(schp->pages[k]),
2010 num_read_xfer))
2011 return -EFAULT;
2012 break;
2013 } else {
2014 if (__copy_to_user(outp, page_address(schp->pages[k]),
2015 num))
2016 return -EFAULT;
2017 num_read_xfer -= num;
2018 if (num_read_xfer <= 0)
2019 break;
2020 outp += num;
2021 }
2022 }
2023
2024 return 0;
2025 }
2026
2027 static void
2028 sg_build_reserve(Sg_fd * sfp, int req_size)
2029 {
2030 Sg_scatter_hold *schp = &sfp->reserve;
2031
2032 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2033 "sg_build_reserve: req_size=%d\n", req_size));
2034 do {
2035 if (req_size < PAGE_SIZE)
2036 req_size = PAGE_SIZE;
2037 if (0 == sg_build_indirect(schp, sfp, req_size))
2038 return;
2039 else
2040 sg_remove_scat(sfp, schp);
2041 req_size >>= 1; /* divide by 2 */
2042 } while (req_size > (PAGE_SIZE / 2));
2043 }
2044
2045 static void
2046 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2047 {
2048 Sg_scatter_hold *req_schp = &srp->data;
2049 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2050 int k, num, rem;
2051
2052 srp->res_used = 1;
2053 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2054 "sg_link_reserve: size=%d\n", size));
2055 rem = size;
2056
2057 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2058 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2059 if (rem <= num) {
2060 req_schp->k_use_sg = k + 1;
2061 req_schp->sglist_len = rsv_schp->sglist_len;
2062 req_schp->pages = rsv_schp->pages;
2063
2064 req_schp->bufflen = size;
2065 req_schp->page_order = rsv_schp->page_order;
2066 break;
2067 } else
2068 rem -= num;
2069 }
2070
2071 if (k >= rsv_schp->k_use_sg)
2072 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2073 "sg_link_reserve: BAD size\n"));
2074 }
2075
2076 static void
2077 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2078 {
2079 Sg_scatter_hold *req_schp = &srp->data;
2080
2081 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2082 "sg_unlink_reserve: req->k_use_sg=%d\n",
2083 (int) req_schp->k_use_sg));
2084 req_schp->k_use_sg = 0;
2085 req_schp->bufflen = 0;
2086 req_schp->pages = NULL;
2087 req_schp->page_order = 0;
2088 req_schp->sglist_len = 0;
2089 srp->res_used = 0;
2090 /* Called without mutex lock to avoid deadlock */
2091 sfp->res_in_use = 0;
2092 }
2093
2094 static Sg_request *
2095 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2096 {
2097 Sg_request *resp;
2098 unsigned long iflags;
2099
2100 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2101 list_for_each_entry(resp, &sfp->rq_list, entry) {
2102 /* look for requests that are ready + not SG_IO owned */
2103 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2104 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2105 resp->done = 2; /* guard against other readers */
2106 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2107 return resp;
2108 }
2109 }
2110 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2111 return NULL;
2112 }
2113
2114 /* always adds to end of list */
2115 static Sg_request *
2116 sg_add_request(Sg_fd * sfp)
2117 {
2118 int k;
2119 unsigned long iflags;
2120 Sg_request *rp = sfp->req_arr;
2121
2122 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2123 if (!list_empty(&sfp->rq_list)) {
2124 if (!sfp->cmd_q)
2125 goto out_unlock;
2126
2127 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2128 if (!rp->parentfp)
2129 break;
2130 }
2131 if (k >= SG_MAX_QUEUE)
2132 goto out_unlock;
2133 }
2134 memset(rp, 0, sizeof (Sg_request));
2135 rp->parentfp = sfp;
2136 rp->header.duration = jiffies_to_msecs(jiffies);
2137 list_add_tail(&rp->entry, &sfp->rq_list);
2138 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2139 return rp;
2140 out_unlock:
2141 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2142 return NULL;
2143 }
2144
2145 /* Return of 1 for found; 0 for not found */
2146 static int
2147 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2148 {
2149 unsigned long iflags;
2150 int res = 0;
2151
2152 if (!sfp || !srp || list_empty(&sfp->rq_list))
2153 return res;
2154 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2155 if (!list_empty(&srp->entry)) {
2156 list_del(&srp->entry);
2157 srp->parentfp = NULL;
2158 res = 1;
2159 }
2160 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2161 return res;
2162 }
2163
2164 static Sg_fd *
2165 sg_add_sfp(Sg_device * sdp)
2166 {
2167 Sg_fd *sfp;
2168 unsigned long iflags;
2169 int bufflen;
2170
2171 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2172 if (!sfp)
2173 return ERR_PTR(-ENOMEM);
2174
2175 init_waitqueue_head(&sfp->read_wait);
2176 rwlock_init(&sfp->rq_list_lock);
2177 INIT_LIST_HEAD(&sfp->rq_list);
2178 kref_init(&sfp->f_ref);
2179 mutex_init(&sfp->f_mutex);
2180 sfp->timeout = SG_DEFAULT_TIMEOUT;
2181 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2182 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2183 sfp->cmd_q = SG_DEF_COMMAND_Q;
2184 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2185 sfp->parentdp = sdp;
2186 write_lock_irqsave(&sdp->sfd_lock, iflags);
2187 if (atomic_read(&sdp->detaching)) {
2188 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2189 return ERR_PTR(-ENODEV);
2190 }
2191 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2192 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2193 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2194 "sg_add_sfp: sfp=0x%p\n", sfp));
2195 if (unlikely(sg_big_buff != def_reserved_size))
2196 sg_big_buff = def_reserved_size;
2197
2198 bufflen = min_t(int, sg_big_buff,
2199 max_sectors_bytes(sdp->device->request_queue));
2200 sg_build_reserve(sfp, bufflen);
2201 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2202 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2203 sfp->reserve.bufflen,
2204 sfp->reserve.k_use_sg));
2205
2206 kref_get(&sdp->d_ref);
2207 __module_get(THIS_MODULE);
2208 return sfp;
2209 }
2210
2211 static void
2212 sg_remove_sfp_usercontext(struct work_struct *work)
2213 {
2214 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2215 struct sg_device *sdp = sfp->parentdp;
2216 Sg_request *srp;
2217 unsigned long iflags;
2218
2219 /* Cleanup any responses which were never read(). */
2220 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2221 while (!list_empty(&sfp->rq_list)) {
2222 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2223 sg_finish_rem_req(srp);
2224 list_del(&srp->entry);
2225 srp->parentfp = NULL;
2226 }
2227 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2228
2229 if (sfp->reserve.bufflen > 0) {
2230 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2231 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2232 (int) sfp->reserve.bufflen,
2233 (int) sfp->reserve.k_use_sg));
2234 sg_remove_scat(sfp, &sfp->reserve);
2235 }
2236
2237 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2238 "sg_remove_sfp: sfp=0x%p\n", sfp));
2239 kfree(sfp);
2240
2241 scsi_device_put(sdp->device);
2242 kref_put(&sdp->d_ref, sg_device_destroy);
2243 module_put(THIS_MODULE);
2244 }
2245
2246 static void
2247 sg_remove_sfp(struct kref *kref)
2248 {
2249 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2250 struct sg_device *sdp = sfp->parentdp;
2251 unsigned long iflags;
2252
2253 write_lock_irqsave(&sdp->sfd_lock, iflags);
2254 list_del(&sfp->sfd_siblings);
2255 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2256
2257 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2258 schedule_work(&sfp->ew.work);
2259 }
2260
2261 #ifdef CONFIG_SCSI_PROC_FS
2262 static int
2263 sg_idr_max_id(int id, void *p, void *data)
2264 {
2265 int *k = data;
2266
2267 if (*k < id)
2268 *k = id;
2269
2270 return 0;
2271 }
2272
2273 static int
2274 sg_last_dev(void)
2275 {
2276 int k = -1;
2277 unsigned long iflags;
2278
2279 read_lock_irqsave(&sg_index_lock, iflags);
2280 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2281 read_unlock_irqrestore(&sg_index_lock, iflags);
2282 return k + 1; /* origin 1 */
2283 }
2284 #endif
2285
2286 /* must be called with sg_index_lock held */
2287 static Sg_device *sg_lookup_dev(int dev)
2288 {
2289 return idr_find(&sg_index_idr, dev);
2290 }
2291
2292 static Sg_device *
2293 sg_get_dev(int dev)
2294 {
2295 struct sg_device *sdp;
2296 unsigned long flags;
2297
2298 read_lock_irqsave(&sg_index_lock, flags);
2299 sdp = sg_lookup_dev(dev);
2300 if (!sdp)
2301 sdp = ERR_PTR(-ENXIO);
2302 else if (atomic_read(&sdp->detaching)) {
2303 /* If sdp->detaching, then the refcount may already be 0, in
2304 * which case it would be a bug to do kref_get().
2305 */
2306 sdp = ERR_PTR(-ENODEV);
2307 } else
2308 kref_get(&sdp->d_ref);
2309 read_unlock_irqrestore(&sg_index_lock, flags);
2310
2311 return sdp;
2312 }
2313
2314 #ifdef CONFIG_SCSI_PROC_FS
2315
2316 static struct proc_dir_entry *sg_proc_sgp = NULL;
2317
2318 static char sg_proc_sg_dirname[] = "scsi/sg";
2319
2320 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2321
2322 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2323 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2324 size_t count, loff_t *off);
2325 static const struct file_operations adio_fops = {
2326 .owner = THIS_MODULE,
2327 .open = sg_proc_single_open_adio,
2328 .read = seq_read,
2329 .llseek = seq_lseek,
2330 .write = sg_proc_write_adio,
2331 .release = single_release,
2332 };
2333
2334 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2335 static ssize_t sg_proc_write_dressz(struct file *filp,
2336 const char __user *buffer, size_t count, loff_t *off);
2337 static const struct file_operations dressz_fops = {
2338 .owner = THIS_MODULE,
2339 .open = sg_proc_single_open_dressz,
2340 .read = seq_read,
2341 .llseek = seq_lseek,
2342 .write = sg_proc_write_dressz,
2343 .release = single_release,
2344 };
2345
2346 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2347 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2348 static const struct file_operations version_fops = {
2349 .owner = THIS_MODULE,
2350 .open = sg_proc_single_open_version,
2351 .read = seq_read,
2352 .llseek = seq_lseek,
2353 .release = single_release,
2354 };
2355
2356 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2357 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2358 static const struct file_operations devhdr_fops = {
2359 .owner = THIS_MODULE,
2360 .open = sg_proc_single_open_devhdr,
2361 .read = seq_read,
2362 .llseek = seq_lseek,
2363 .release = single_release,
2364 };
2365
2366 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2367 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2368 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2369 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2370 static void dev_seq_stop(struct seq_file *s, void *v);
2371 static const struct file_operations dev_fops = {
2372 .owner = THIS_MODULE,
2373 .open = sg_proc_open_dev,
2374 .read = seq_read,
2375 .llseek = seq_lseek,
2376 .release = seq_release,
2377 };
2378 static const struct seq_operations dev_seq_ops = {
2379 .start = dev_seq_start,
2380 .next = dev_seq_next,
2381 .stop = dev_seq_stop,
2382 .show = sg_proc_seq_show_dev,
2383 };
2384
2385 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2386 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2387 static const struct file_operations devstrs_fops = {
2388 .owner = THIS_MODULE,
2389 .open = sg_proc_open_devstrs,
2390 .read = seq_read,
2391 .llseek = seq_lseek,
2392 .release = seq_release,
2393 };
2394 static const struct seq_operations devstrs_seq_ops = {
2395 .start = dev_seq_start,
2396 .next = dev_seq_next,
2397 .stop = dev_seq_stop,
2398 .show = sg_proc_seq_show_devstrs,
2399 };
2400
2401 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2402 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2403 static const struct file_operations debug_fops = {
2404 .owner = THIS_MODULE,
2405 .open = sg_proc_open_debug,
2406 .read = seq_read,
2407 .llseek = seq_lseek,
2408 .release = seq_release,
2409 };
2410 static const struct seq_operations debug_seq_ops = {
2411 .start = dev_seq_start,
2412 .next = dev_seq_next,
2413 .stop = dev_seq_stop,
2414 .show = sg_proc_seq_show_debug,
2415 };
2416
2417
2418 struct sg_proc_leaf {
2419 const char * name;
2420 const struct file_operations * fops;
2421 };
2422
2423 static const struct sg_proc_leaf sg_proc_leaf_arr[] = {
2424 {"allow_dio", &adio_fops},
2425 {"debug", &debug_fops},
2426 {"def_reserved_size", &dressz_fops},
2427 {"device_hdr", &devhdr_fops},
2428 {"devices", &dev_fops},
2429 {"device_strs", &devstrs_fops},
2430 {"version", &version_fops}
2431 };
2432
2433 static int
2434 sg_proc_init(void)
2435 {
2436 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2437 int k;
2438
2439 sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2440 if (!sg_proc_sgp)
2441 return 1;
2442 for (k = 0; k < num_leaves; ++k) {
2443 const struct sg_proc_leaf *leaf = &sg_proc_leaf_arr[k];
2444 umode_t mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2445 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2446 }
2447 return 0;
2448 }
2449
2450 static void
2451 sg_proc_cleanup(void)
2452 {
2453 int k;
2454 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2455
2456 if (!sg_proc_sgp)
2457 return;
2458 for (k = 0; k < num_leaves; ++k)
2459 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2460 remove_proc_entry(sg_proc_sg_dirname, NULL);
2461 }
2462
2463
2464 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2465 {
2466 seq_printf(s, "%d\n", *((int *)s->private));
2467 return 0;
2468 }
2469
2470 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2471 {
2472 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2473 }
2474
2475 static ssize_t
2476 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2477 size_t count, loff_t *off)
2478 {
2479 int err;
2480 unsigned long num;
2481
2482 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2483 return -EACCES;
2484 err = kstrtoul_from_user(buffer, count, 0, &num);
2485 if (err)
2486 return err;
2487 sg_allow_dio = num ? 1 : 0;
2488 return count;
2489 }
2490
2491 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2492 {
2493 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2494 }
2495
2496 static ssize_t
2497 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2498 size_t count, loff_t *off)
2499 {
2500 int err;
2501 unsigned long k = ULONG_MAX;
2502
2503 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2504 return -EACCES;
2505
2506 err = kstrtoul_from_user(buffer, count, 0, &k);
2507 if (err)
2508 return err;
2509 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2510 sg_big_buff = k;
2511 return count;
2512 }
2513 return -ERANGE;
2514 }
2515
2516 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2517 {
2518 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2519 sg_version_date);
2520 return 0;
2521 }
2522
2523 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2524 {
2525 return single_open(file, sg_proc_seq_show_version, NULL);
2526 }
2527
2528 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2529 {
2530 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2531 return 0;
2532 }
2533
2534 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2535 {
2536 return single_open(file, sg_proc_seq_show_devhdr, NULL);
2537 }
2538
2539 struct sg_proc_deviter {
2540 loff_t index;
2541 size_t max;
2542 };
2543
2544 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2545 {
2546 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2547
2548 s->private = it;
2549 if (! it)
2550 return NULL;
2551
2552 it->index = *pos;
2553 it->max = sg_last_dev();
2554 if (it->index >= it->max)
2555 return NULL;
2556 return it;
2557 }
2558
2559 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2560 {
2561 struct sg_proc_deviter * it = s->private;
2562
2563 *pos = ++it->index;
2564 return (it->index < it->max) ? it : NULL;
2565 }
2566
2567 static void dev_seq_stop(struct seq_file *s, void *v)
2568 {
2569 kfree(s->private);
2570 }
2571
2572 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2573 {
2574 return seq_open(file, &dev_seq_ops);
2575 }
2576
2577 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2578 {
2579 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2580 Sg_device *sdp;
2581 struct scsi_device *scsidp;
2582 unsigned long iflags;
2583
2584 read_lock_irqsave(&sg_index_lock, iflags);
2585 sdp = it ? sg_lookup_dev(it->index) : NULL;
2586 if ((NULL == sdp) || (NULL == sdp->device) ||
2587 (atomic_read(&sdp->detaching)))
2588 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2589 else {
2590 scsidp = sdp->device;
2591 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2592 scsidp->host->host_no, scsidp->channel,
2593 scsidp->id, scsidp->lun, (int) scsidp->type,
2594 1,
2595 (int) scsidp->queue_depth,
2596 (int) atomic_read(&scsidp->device_busy),
2597 (int) scsi_device_online(scsidp));
2598 }
2599 read_unlock_irqrestore(&sg_index_lock, iflags);
2600 return 0;
2601 }
2602
2603 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2604 {
2605 return seq_open(file, &devstrs_seq_ops);
2606 }
2607
2608 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2609 {
2610 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2611 Sg_device *sdp;
2612 struct scsi_device *scsidp;
2613 unsigned long iflags;
2614
2615 read_lock_irqsave(&sg_index_lock, iflags);
2616 sdp = it ? sg_lookup_dev(it->index) : NULL;
2617 scsidp = sdp ? sdp->device : NULL;
2618 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2619 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2620 scsidp->vendor, scsidp->model, scsidp->rev);
2621 else
2622 seq_puts(s, "<no active device>\n");
2623 read_unlock_irqrestore(&sg_index_lock, iflags);
2624 return 0;
2625 }
2626
2627 /* must be called while holding sg_index_lock */
2628 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2629 {
2630 int k, new_interface, blen, usg;
2631 Sg_request *srp;
2632 Sg_fd *fp;
2633 const sg_io_hdr_t *hp;
2634 const char * cp;
2635 unsigned int ms;
2636
2637 k = 0;
2638 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2639 k++;
2640 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2641 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2642 "(res)sgat=%d low_dma=%d\n", k,
2643 jiffies_to_msecs(fp->timeout),
2644 fp->reserve.bufflen,
2645 (int) fp->reserve.k_use_sg,
2646 (int) sdp->device->host->unchecked_isa_dma);
2647 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2648 (int) fp->cmd_q, (int) fp->force_packid,
2649 (int) fp->keep_orphan);
2650 list_for_each_entry(srp, &fp->rq_list, entry) {
2651 hp = &srp->header;
2652 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2653 if (srp->res_used) {
2654 if (new_interface &&
2655 (SG_FLAG_MMAP_IO & hp->flags))
2656 cp = " mmap>> ";
2657 else
2658 cp = " rb>> ";
2659 } else {
2660 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2661 cp = " dio>> ";
2662 else
2663 cp = " ";
2664 }
2665 seq_puts(s, cp);
2666 blen = srp->data.bufflen;
2667 usg = srp->data.k_use_sg;
2668 seq_puts(s, srp->done ?
2669 ((1 == srp->done) ? "rcv:" : "fin:")
2670 : "act:");
2671 seq_printf(s, " id=%d blen=%d",
2672 srp->header.pack_id, blen);
2673 if (srp->done)
2674 seq_printf(s, " dur=%d", hp->duration);
2675 else {
2676 ms = jiffies_to_msecs(jiffies);
2677 seq_printf(s, " t_o/elap=%d/%d",
2678 (new_interface ? hp->timeout :
2679 jiffies_to_msecs(fp->timeout)),
2680 (ms > hp->duration ? ms - hp->duration : 0));
2681 }
2682 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2683 (int) srp->data.cmd_opcode);
2684 }
2685 if (list_empty(&fp->rq_list))
2686 seq_puts(s, " No requests active\n");
2687 read_unlock(&fp->rq_list_lock);
2688 }
2689 }
2690
2691 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2692 {
2693 return seq_open(file, &debug_seq_ops);
2694 }
2695
2696 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2697 {
2698 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2699 Sg_device *sdp;
2700 unsigned long iflags;
2701
2702 if (it && (0 == it->index))
2703 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2704 (int)it->max, sg_big_buff);
2705
2706 read_lock_irqsave(&sg_index_lock, iflags);
2707 sdp = it ? sg_lookup_dev(it->index) : NULL;
2708 if (NULL == sdp)
2709 goto skip;
2710 read_lock(&sdp->sfd_lock);
2711 if (!list_empty(&sdp->sfds)) {
2712 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2713 if (atomic_read(&sdp->detaching))
2714 seq_puts(s, "detaching pending close ");
2715 else if (sdp->device) {
2716 struct scsi_device *scsidp = sdp->device;
2717
2718 seq_printf(s, "%d:%d:%d:%llu em=%d",
2719 scsidp->host->host_no,
2720 scsidp->channel, scsidp->id,
2721 scsidp->lun,
2722 scsidp->host->hostt->emulated);
2723 }
2724 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2725 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2726 sg_proc_debug_helper(s, sdp);
2727 }
2728 read_unlock(&sdp->sfd_lock);
2729 skip:
2730 read_unlock_irqrestore(&sg_index_lock, iflags);
2731 return 0;
2732 }
2733
2734 #endif /* CONFIG_SCSI_PROC_FS */
2735
2736 module_init(init_sg);
2737 module_exit(exit_sg);
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