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Linux 4.19.133
[linux/fpc-iii.git] / drivers / scsi / sg.c
blob6bb45ae19d5873bbf6b2555607d18840ba3e014e
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 #endif
71
72 #define SG_ALLOW_DIO_DEF 0
73
74 #define SG_MAX_DEVS 32768
75
76 /* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type
77 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater
78 * than 16 bytes are "variable length" whose length is a multiple of 4
79 */
80 #define SG_MAX_CDB_SIZE 252
81
82 #define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
83
84 int sg_big_buff = SG_DEF_RESERVED_SIZE;
85 /* N.B. This variable is readable and writeable via
86 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
87 of this size (or less if there is not enough memory) will be reserved
88 for use by this file descriptor. [Deprecated usage: this variable is also
89 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
90 the kernel (i.e. it is not a module).] */
91 static int def_reserved_size = -1; /* picks up init parameter */
92 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
93
94 static int scatter_elem_sz = SG_SCATTER_SZ;
95 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
96
97 #define SG_SECTOR_SZ 512
98
99 static int sg_add_device(struct device *, struct class_interface *);
100 static void sg_remove_device(struct device *, struct class_interface *);
101
102 static DEFINE_IDR(sg_index_idr);
103 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
104 file descriptor list for device */
105
106 static struct class_interface sg_interface = {
107 .add_dev = sg_add_device,
108 .remove_dev = sg_remove_device,
109 };
110
111 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
112 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
113 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
114 unsigned bufflen; /* Size of (aggregate) data buffer */
115 struct page **pages;
116 int page_order;
117 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
118 unsigned char cmd_opcode; /* first byte of command */
119 } Sg_scatter_hold;
120
121 struct sg_device; /* forward declarations */
122 struct sg_fd;
123
124 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
125 struct list_head entry; /* list entry */
126 struct sg_fd *parentfp; /* NULL -> not in use */
127 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
128 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
129 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
130 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
131 char orphan; /* 1 -> drop on sight, 0 -> normal */
132 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
133 /* done protected by rq_list_lock */
134 char done; /* 0->before bh, 1->before read, 2->read */
135 struct request *rq;
136 struct bio *bio;
137 struct execute_work ew;
138 } Sg_request;
139
140 typedef struct sg_fd { /* holds the state of a file descriptor */
141 struct list_head sfd_siblings; /* protected by device's sfd_lock */
142 struct sg_device *parentdp; /* owning device */
143 wait_queue_head_t read_wait; /* queue read until command done */
144 rwlock_t rq_list_lock; /* protect access to list in req_arr */
145 struct mutex f_mutex; /* protect against changes in this fd */
146 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
147 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
148 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
149 struct list_head rq_list; /* head of request list */
150 struct fasync_struct *async_qp; /* used by asynchronous notification */
151 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
152 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
153 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
154 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
155 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
156 char mmap_called; /* 0 -> mmap() never called on this fd */
157 char res_in_use; /* 1 -> 'reserve' array in use */
158 struct kref f_ref;
159 struct execute_work ew;
160 } Sg_fd;
161
162 typedef struct sg_device { /* holds the state of each scsi generic device */
163 struct scsi_device *device;
164 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */
165 struct mutex open_rel_lock; /* held when in open() or release() */
166 int sg_tablesize; /* adapter's max scatter-gather table size */
167 u32 index; /* device index number */
168 struct list_head sfds;
169 rwlock_t sfd_lock; /* protect access to sfd list */
170 atomic_t detaching; /* 0->device usable, 1->device detaching */
171 bool exclude; /* 1->open(O_EXCL) succeeded and is active */
172 int open_cnt; /* count of opens (perhaps < num(sfds) ) */
173 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
174 struct gendisk *disk;
175 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
176 struct kref d_ref;
177 } Sg_device;
178
179 /* tasklet or soft irq callback */
180 static void sg_rq_end_io(struct request *rq, blk_status_t status);
181 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
182 static int sg_finish_rem_req(Sg_request * srp);
183 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
184 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
185 Sg_request * srp);
186 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
187 const char __user *buf, size_t count, int blocking,
188 int read_only, int sg_io_owned, Sg_request **o_srp);
189 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
190 unsigned char *cmnd, int timeout, int blocking);
191 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
192 static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
193 static void sg_build_reserve(Sg_fd * sfp, int req_size);
194 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
195 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
196 static Sg_fd *sg_add_sfp(Sg_device * sdp);
197 static void sg_remove_sfp(struct kref *);
198 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
199 static Sg_request *sg_add_request(Sg_fd * sfp);
200 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
201 static Sg_device *sg_get_dev(int dev);
202 static void sg_device_destroy(struct kref *kref);
203
204 #define SZ_SG_HEADER sizeof(struct sg_header)
205 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
206 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
207 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
208
209 #define sg_printk(prefix, sdp, fmt, a...) \
210 sdev_prefix_printk(prefix, (sdp)->device, \
211 (sdp)->disk->disk_name, fmt, ##a)
212
213 /*
214 * The SCSI interfaces that use read() and write() as an asynchronous variant of
215 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways
216 * to trigger read() and write() calls from various contexts with elevated
217 * privileges. This can lead to kernel memory corruption (e.g. if these
218 * interfaces are called through splice()) and privilege escalation inside
219 * userspace (e.g. if a process with access to such a device passes a file
220 * descriptor to a SUID binary as stdin/stdout/stderr).
221 *
222 * This function provides protection for the legacy API by restricting the
223 * calling context.
224 */
225 static int sg_check_file_access(struct file *filp, const char *caller)
226 {
227 if (filp->f_cred != current_real_cred()) {
228 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
229 caller, task_tgid_vnr(current), current->comm);
230 return -EPERM;
231 }
232 if (uaccess_kernel()) {
233 pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n",
234 caller, task_tgid_vnr(current), current->comm);
235 return -EACCES;
236 }
237 return 0;
238 }
239
240 static int sg_allow_access(struct file *filp, unsigned char *cmd)
241 {
242 struct sg_fd *sfp = filp->private_data;
243
244 if (sfp->parentdp->device->type == TYPE_SCANNER)
245 return 0;
246
247 return blk_verify_command(cmd, filp->f_mode);
248 }
249
250 static int
251 open_wait(Sg_device *sdp, int flags)
252 {
253 int retval = 0;
254
255 if (flags & O_EXCL) {
256 while (sdp->open_cnt > 0) {
257 mutex_unlock(&sdp->open_rel_lock);
258 retval = wait_event_interruptible(sdp->open_wait,
259 (atomic_read(&sdp->detaching) ||
260 !sdp->open_cnt));
261 mutex_lock(&sdp->open_rel_lock);
262
263 if (retval) /* -ERESTARTSYS */
264 return retval;
265 if (atomic_read(&sdp->detaching))
266 return -ENODEV;
267 }
268 } else {
269 while (sdp->exclude) {
270 mutex_unlock(&sdp->open_rel_lock);
271 retval = wait_event_interruptible(sdp->open_wait,
272 (atomic_read(&sdp->detaching) ||
273 !sdp->exclude));
274 mutex_lock(&sdp->open_rel_lock);
275
276 if (retval) /* -ERESTARTSYS */
277 return retval;
278 if (atomic_read(&sdp->detaching))
279 return -ENODEV;
280 }
281 }
282
283 return retval;
284 }
285
286 /* Returns 0 on success, else a negated errno value */
287 static int
288 sg_open(struct inode *inode, struct file *filp)
289 {
290 int dev = iminor(inode);
291 int flags = filp->f_flags;
292 struct request_queue *q;
293 Sg_device *sdp;
294 Sg_fd *sfp;
295 int retval;
296
297 nonseekable_open(inode, filp);
298 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
299 return -EPERM; /* Can't lock it with read only access */
300 sdp = sg_get_dev(dev);
301 if (IS_ERR(sdp))
302 return PTR_ERR(sdp);
303
304 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
305 "sg_open: flags=0x%x\n", flags));
306
307 /* This driver's module count bumped by fops_get in <linux/fs.h> */
308 /* Prevent the device driver from vanishing while we sleep */
309 retval = scsi_device_get(sdp->device);
310 if (retval)
311 goto sg_put;
312
313 retval = scsi_autopm_get_device(sdp->device);
314 if (retval)
315 goto sdp_put;
316
317 /* scsi_block_when_processing_errors() may block so bypass
318 * check if O_NONBLOCK. Permits SCSI commands to be issued
319 * during error recovery. Tread carefully. */
320 if (!((flags & O_NONBLOCK) ||
321 scsi_block_when_processing_errors(sdp->device))) {
322 retval = -ENXIO;
323 /* we are in error recovery for this device */
324 goto error_out;
325 }
326
327 mutex_lock(&sdp->open_rel_lock);
328 if (flags & O_NONBLOCK) {
329 if (flags & O_EXCL) {
330 if (sdp->open_cnt > 0) {
331 retval = -EBUSY;
332 goto error_mutex_locked;
333 }
334 } else {
335 if (sdp->exclude) {
336 retval = -EBUSY;
337 goto error_mutex_locked;
338 }
339 }
340 } else {
341 retval = open_wait(sdp, flags);
342 if (retval) /* -ERESTARTSYS or -ENODEV */
343 goto error_mutex_locked;
344 }
345
346 /* N.B. at this point we are holding the open_rel_lock */
347 if (flags & O_EXCL)
348 sdp->exclude = true;
349
350 if (sdp->open_cnt < 1) { /* no existing opens */
351 sdp->sgdebug = 0;
352 q = sdp->device->request_queue;
353 sdp->sg_tablesize = queue_max_segments(q);
354 }
355 sfp = sg_add_sfp(sdp);
356 if (IS_ERR(sfp)) {
357 retval = PTR_ERR(sfp);
358 goto out_undo;
359 }
360
361 filp->private_data = sfp;
362 sdp->open_cnt++;
363 mutex_unlock(&sdp->open_rel_lock);
364
365 retval = 0;
366 sg_put:
367 kref_put(&sdp->d_ref, sg_device_destroy);
368 return retval;
369
370 out_undo:
371 if (flags & O_EXCL) {
372 sdp->exclude = false; /* undo if error */
373 wake_up_interruptible(&sdp->open_wait);
374 }
375 error_mutex_locked:
376 mutex_unlock(&sdp->open_rel_lock);
377 error_out:
378 scsi_autopm_put_device(sdp->device);
379 sdp_put:
380 scsi_device_put(sdp->device);
381 goto sg_put;
382 }
383
384 /* Release resources associated with a successful sg_open()
385 * Returns 0 on success, else a negated errno value */
386 static int
387 sg_release(struct inode *inode, struct file *filp)
388 {
389 Sg_device *sdp;
390 Sg_fd *sfp;
391
392 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
393 return -ENXIO;
394 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
395
396 mutex_lock(&sdp->open_rel_lock);
397 scsi_autopm_put_device(sdp->device);
398 kref_put(&sfp->f_ref, sg_remove_sfp);
399 sdp->open_cnt--;
400
401 /* possibly many open()s waiting on exlude clearing, start many;
402 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
403 if (sdp->exclude) {
404 sdp->exclude = false;
405 wake_up_interruptible_all(&sdp->open_wait);
406 } else if (0 == sdp->open_cnt) {
407 wake_up_interruptible(&sdp->open_wait);
408 }
409 mutex_unlock(&sdp->open_rel_lock);
410 return 0;
411 }
412
413 static ssize_t
414 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
415 {
416 Sg_device *sdp;
417 Sg_fd *sfp;
418 Sg_request *srp;
419 int req_pack_id = -1;
420 sg_io_hdr_t *hp;
421 struct sg_header *old_hdr = NULL;
422 int retval = 0;
423
424 /*
425 * This could cause a response to be stranded. Close the associated
426 * file descriptor to free up any resources being held.
427 */
428 retval = sg_check_file_access(filp, __func__);
429 if (retval)
430 return retval;
431
432 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
433 return -ENXIO;
434 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
435 "sg_read: count=%d\n", (int) count));
436
437 if (!access_ok(VERIFY_WRITE, buf, count))
438 return -EFAULT;
439 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
440 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
441 if (!old_hdr)
442 return -ENOMEM;
443 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
444 retval = -EFAULT;
445 goto free_old_hdr;
446 }
447 if (old_hdr->reply_len < 0) {
448 if (count >= SZ_SG_IO_HDR) {
449 sg_io_hdr_t *new_hdr;
450 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
451 if (!new_hdr) {
452 retval = -ENOMEM;
453 goto free_old_hdr;
454 }
455 retval =__copy_from_user
456 (new_hdr, buf, SZ_SG_IO_HDR);
457 req_pack_id = new_hdr->pack_id;
458 kfree(new_hdr);
459 if (retval) {
460 retval = -EFAULT;
461 goto free_old_hdr;
462 }
463 }
464 } else
465 req_pack_id = old_hdr->pack_id;
466 }
467 srp = sg_get_rq_mark(sfp, req_pack_id);
468 if (!srp) { /* now wait on packet to arrive */
469 if (atomic_read(&sdp->detaching)) {
470 retval = -ENODEV;
471 goto free_old_hdr;
472 }
473 if (filp->f_flags & O_NONBLOCK) {
474 retval = -EAGAIN;
475 goto free_old_hdr;
476 }
477 retval = wait_event_interruptible(sfp->read_wait,
478 (atomic_read(&sdp->detaching) ||
479 (srp = sg_get_rq_mark(sfp, req_pack_id))));
480 if (atomic_read(&sdp->detaching)) {
481 retval = -ENODEV;
482 goto free_old_hdr;
483 }
484 if (retval) {
485 /* -ERESTARTSYS as signal hit process */
486 goto free_old_hdr;
487 }
488 }
489 if (srp->header.interface_id != '\0') {
490 retval = sg_new_read(sfp, buf, count, srp);
491 goto free_old_hdr;
492 }
493
494 hp = &srp->header;
495 if (old_hdr == NULL) {
496 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
497 if (! old_hdr) {
498 retval = -ENOMEM;
499 goto free_old_hdr;
500 }
501 }
502 memset(old_hdr, 0, SZ_SG_HEADER);
503 old_hdr->reply_len = (int) hp->timeout;
504 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
505 old_hdr->pack_id = hp->pack_id;
506 old_hdr->twelve_byte =
507 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
508 old_hdr->target_status = hp->masked_status;
509 old_hdr->host_status = hp->host_status;
510 old_hdr->driver_status = hp->driver_status;
511 if ((CHECK_CONDITION & hp->masked_status) ||
512 (DRIVER_SENSE & hp->driver_status))
513 memcpy(old_hdr->sense_buffer, srp->sense_b,
514 sizeof (old_hdr->sense_buffer));
515 switch (hp->host_status) {
516 /* This setup of 'result' is for backward compatibility and is best
517 ignored by the user who should use target, host + driver status */
518 case DID_OK:
519 case DID_PASSTHROUGH:
520 case DID_SOFT_ERROR:
521 old_hdr->result = 0;
522 break;
523 case DID_NO_CONNECT:
524 case DID_BUS_BUSY:
525 case DID_TIME_OUT:
526 old_hdr->result = EBUSY;
527 break;
528 case DID_BAD_TARGET:
529 case DID_ABORT:
530 case DID_PARITY:
531 case DID_RESET:
532 case DID_BAD_INTR:
533 old_hdr->result = EIO;
534 break;
535 case DID_ERROR:
536 old_hdr->result = (srp->sense_b[0] == 0 &&
537 hp->masked_status == GOOD) ? 0 : EIO;
538 break;
539 default:
540 old_hdr->result = EIO;
541 break;
542 }
543
544 /* Now copy the result back to the user buffer. */
545 if (count >= SZ_SG_HEADER) {
546 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
547 retval = -EFAULT;
548 goto free_old_hdr;
549 }
550 buf += SZ_SG_HEADER;
551 if (count > old_hdr->reply_len)
552 count = old_hdr->reply_len;
553 if (count > SZ_SG_HEADER) {
554 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
555 retval = -EFAULT;
556 goto free_old_hdr;
557 }
558 }
559 } else
560 count = (old_hdr->result == 0) ? 0 : -EIO;
561 sg_finish_rem_req(srp);
562 sg_remove_request(sfp, srp);
563 retval = count;
564 free_old_hdr:
565 kfree(old_hdr);
566 return retval;
567 }
568
569 static ssize_t
570 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
571 {
572 sg_io_hdr_t *hp = &srp->header;
573 int err = 0, err2;
574 int len;
575
576 if (count < SZ_SG_IO_HDR) {
577 err = -EINVAL;
578 goto err_out;
579 }
580 hp->sb_len_wr = 0;
581 if ((hp->mx_sb_len > 0) && hp->sbp) {
582 if ((CHECK_CONDITION & hp->masked_status) ||
583 (DRIVER_SENSE & hp->driver_status)) {
584 int sb_len = SCSI_SENSE_BUFFERSIZE;
585 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
586 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
587 len = (len > sb_len) ? sb_len : len;
588 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
589 err = -EFAULT;
590 goto err_out;
591 }
592 hp->sb_len_wr = len;
593 }
594 }
595 if (hp->masked_status || hp->host_status || hp->driver_status)
596 hp->info |= SG_INFO_CHECK;
597 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
598 err = -EFAULT;
599 goto err_out;
600 }
601 err_out:
602 err2 = sg_finish_rem_req(srp);
603 sg_remove_request(sfp, srp);
604 return err ? : err2 ? : count;
605 }
606
607 static ssize_t
608 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
609 {
610 int mxsize, cmd_size, k;
611 int input_size, blocking;
612 unsigned char opcode;
613 Sg_device *sdp;
614 Sg_fd *sfp;
615 Sg_request *srp;
616 struct sg_header old_hdr;
617 sg_io_hdr_t *hp;
618 unsigned char cmnd[SG_MAX_CDB_SIZE];
619 int retval;
620
621 retval = sg_check_file_access(filp, __func__);
622 if (retval)
623 return retval;
624
625 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
626 return -ENXIO;
627 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
628 "sg_write: count=%d\n", (int) count));
629 if (atomic_read(&sdp->detaching))
630 return -ENODEV;
631 if (!((filp->f_flags & O_NONBLOCK) ||
632 scsi_block_when_processing_errors(sdp->device)))
633 return -ENXIO;
634
635 if (!access_ok(VERIFY_READ, buf, count))
636 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
637 if (count < SZ_SG_HEADER)
638 return -EIO;
639 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
640 return -EFAULT;
641 blocking = !(filp->f_flags & O_NONBLOCK);
642 if (old_hdr.reply_len < 0)
643 return sg_new_write(sfp, filp, buf, count,
644 blocking, 0, 0, NULL);
645 if (count < (SZ_SG_HEADER + 6))
646 return -EIO; /* The minimum scsi command length is 6 bytes. */
647
648 if (!(srp = sg_add_request(sfp))) {
649 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
650 "sg_write: queue full\n"));
651 return -EDOM;
652 }
653 buf += SZ_SG_HEADER;
654 __get_user(opcode, buf);
655 mutex_lock(&sfp->f_mutex);
656 if (sfp->next_cmd_len > 0) {
657 cmd_size = sfp->next_cmd_len;
658 sfp->next_cmd_len = 0; /* reset so only this write() effected */
659 } else {
660 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
661 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
662 cmd_size = 12;
663 }
664 mutex_unlock(&sfp->f_mutex);
665 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
666 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
667 /* Determine buffer size. */
668 input_size = count - cmd_size;
669 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
670 mxsize -= SZ_SG_HEADER;
671 input_size -= SZ_SG_HEADER;
672 if (input_size < 0) {
673 sg_remove_request(sfp, srp);
674 return -EIO; /* User did not pass enough bytes for this command. */
675 }
676 hp = &srp->header;
677 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
678 hp->cmd_len = (unsigned char) cmd_size;
679 hp->iovec_count = 0;
680 hp->mx_sb_len = 0;
681 if (input_size > 0)
682 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
683 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
684 else
685 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
686 hp->dxfer_len = mxsize;
687 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
688 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
689 hp->dxferp = (char __user *)buf + cmd_size;
690 else
691 hp->dxferp = NULL;
692 hp->sbp = NULL;
693 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
694 hp->flags = input_size; /* structure abuse ... */
695 hp->pack_id = old_hdr.pack_id;
696 hp->usr_ptr = NULL;
697 if (__copy_from_user(cmnd, buf, cmd_size)) {
698 sg_remove_request(sfp, srp);
699 return -EFAULT;
700 }
701 /*
702 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
703 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
704 * is a non-zero input_size, so emit a warning.
705 */
706 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
707 printk_ratelimited(KERN_WARNING
708 "sg_write: data in/out %d/%d bytes "
709 "for SCSI command 0x%x-- guessing "
710 "data in;\n program %s not setting "
711 "count and/or reply_len properly\n",
712 old_hdr.reply_len - (int)SZ_SG_HEADER,
713 input_size, (unsigned int) cmnd[0],
714 current->comm);
715 }
716 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
717 return (k < 0) ? k : count;
718 }
719
720 static ssize_t
721 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
722 size_t count, int blocking, int read_only, int sg_io_owned,
723 Sg_request **o_srp)
724 {
725 int k;
726 Sg_request *srp;
727 sg_io_hdr_t *hp;
728 unsigned char cmnd[SG_MAX_CDB_SIZE];
729 int timeout;
730 unsigned long ul_timeout;
731
732 if (count < SZ_SG_IO_HDR)
733 return -EINVAL;
734 if (!access_ok(VERIFY_READ, buf, count))
735 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
736
737 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
738 if (!(srp = sg_add_request(sfp))) {
739 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
740 "sg_new_write: queue full\n"));
741 return -EDOM;
742 }
743 srp->sg_io_owned = sg_io_owned;
744 hp = &srp->header;
745 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
746 sg_remove_request(sfp, srp);
747 return -EFAULT;
748 }
749 if (hp->interface_id != 'S') {
750 sg_remove_request(sfp, srp);
751 return -ENOSYS;
752 }
753 if (hp->flags & SG_FLAG_MMAP_IO) {
754 if (hp->dxfer_len > sfp->reserve.bufflen) {
755 sg_remove_request(sfp, srp);
756 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
757 }
758 if (hp->flags & SG_FLAG_DIRECT_IO) {
759 sg_remove_request(sfp, srp);
760 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
761 }
762 if (sfp->res_in_use) {
763 sg_remove_request(sfp, srp);
764 return -EBUSY; /* reserve buffer already being used */
765 }
766 }
767 ul_timeout = msecs_to_jiffies(srp->header.timeout);
768 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
769 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
770 sg_remove_request(sfp, srp);
771 return -EMSGSIZE;
772 }
773 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
774 sg_remove_request(sfp, srp);
775 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
776 }
777 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
778 sg_remove_request(sfp, srp);
779 return -EFAULT;
780 }
781 if (read_only && sg_allow_access(file, cmnd)) {
782 sg_remove_request(sfp, srp);
783 return -EPERM;
784 }
785 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
786 if (k < 0)
787 return k;
788 if (o_srp)
789 *o_srp = srp;
790 return count;
791 }
792
793 static int
794 sg_common_write(Sg_fd * sfp, Sg_request * srp,
795 unsigned char *cmnd, int timeout, int blocking)
796 {
797 int k, at_head;
798 Sg_device *sdp = sfp->parentdp;
799 sg_io_hdr_t *hp = &srp->header;
800
801 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
802 hp->status = 0;
803 hp->masked_status = 0;
804 hp->msg_status = 0;
805 hp->info = 0;
806 hp->host_status = 0;
807 hp->driver_status = 0;
808 hp->resid = 0;
809 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
810 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
811 (int) cmnd[0], (int) hp->cmd_len));
812
813 if (hp->dxfer_len >= SZ_256M) {
814 sg_remove_request(sfp, srp);
815 return -EINVAL;
816 }
817
818 k = sg_start_req(srp, cmnd);
819 if (k) {
820 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
821 "sg_common_write: start_req err=%d\n", k));
822 sg_finish_rem_req(srp);
823 sg_remove_request(sfp, srp);
824 return k; /* probably out of space --> ENOMEM */
825 }
826 if (atomic_read(&sdp->detaching)) {
827 if (srp->bio) {
828 scsi_req_free_cmd(scsi_req(srp->rq));
829 blk_end_request_all(srp->rq, BLK_STS_IOERR);
830 srp->rq = NULL;
831 }
832
833 sg_finish_rem_req(srp);
834 sg_remove_request(sfp, srp);
835 return -ENODEV;
836 }
837
838 hp->duration = jiffies_to_msecs(jiffies);
839 if (hp->interface_id != '\0' && /* v3 (or later) interface */
840 (SG_FLAG_Q_AT_TAIL & hp->flags))
841 at_head = 0;
842 else
843 at_head = 1;
844
845 srp->rq->timeout = timeout;
846 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
847 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
848 srp->rq, at_head, sg_rq_end_io);
849 return 0;
850 }
851
852 static int srp_done(Sg_fd *sfp, Sg_request *srp)
853 {
854 unsigned long flags;
855 int ret;
856
857 read_lock_irqsave(&sfp->rq_list_lock, flags);
858 ret = srp->done;
859 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
860 return ret;
861 }
862
863 static int max_sectors_bytes(struct request_queue *q)
864 {
865 unsigned int max_sectors = queue_max_sectors(q);
866
867 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
868
869 return max_sectors << 9;
870 }
871
872 static void
873 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
874 {
875 Sg_request *srp;
876 int val;
877 unsigned int ms;
878
879 val = 0;
880 list_for_each_entry(srp, &sfp->rq_list, entry) {
881 if (val >= SG_MAX_QUEUE)
882 break;
883 rinfo[val].req_state = srp->done + 1;
884 rinfo[val].problem =
885 srp->header.masked_status &
886 srp->header.host_status &
887 srp->header.driver_status;
888 if (srp->done)
889 rinfo[val].duration =
890 srp->header.duration;
891 else {
892 ms = jiffies_to_msecs(jiffies);
893 rinfo[val].duration =
894 (ms > srp->header.duration) ?
895 (ms - srp->header.duration) : 0;
896 }
897 rinfo[val].orphan = srp->orphan;
898 rinfo[val].sg_io_owned = srp->sg_io_owned;
899 rinfo[val].pack_id = srp->header.pack_id;
900 rinfo[val].usr_ptr = srp->header.usr_ptr;
901 val++;
902 }
903 }
904
905 static long
906 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
907 {
908 void __user *p = (void __user *)arg;
909 int __user *ip = p;
910 int result, val, read_only;
911 Sg_device *sdp;
912 Sg_fd *sfp;
913 Sg_request *srp;
914 unsigned long iflags;
915
916 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
917 return -ENXIO;
918
919 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
920 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
921 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
922
923 switch (cmd_in) {
924 case SG_IO:
925 if (atomic_read(&sdp->detaching))
926 return -ENODEV;
927 if (!scsi_block_when_processing_errors(sdp->device))
928 return -ENXIO;
929 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
930 return -EFAULT;
931 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
932 1, read_only, 1, &srp);
933 if (result < 0)
934 return result;
935 result = wait_event_interruptible(sfp->read_wait,
936 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
937 if (atomic_read(&sdp->detaching))
938 return -ENODEV;
939 write_lock_irq(&sfp->rq_list_lock);
940 if (srp->done) {
941 srp->done = 2;
942 write_unlock_irq(&sfp->rq_list_lock);
943 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
944 return (result < 0) ? result : 0;
945 }
946 srp->orphan = 1;
947 write_unlock_irq(&sfp->rq_list_lock);
948 return result; /* -ERESTARTSYS because signal hit process */
949 case SG_SET_TIMEOUT:
950 result = get_user(val, ip);
951 if (result)
952 return result;
953 if (val < 0)
954 return -EIO;
955 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
956 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
957 INT_MAX);
958 sfp->timeout_user = val;
959 sfp->timeout = mult_frac(val, HZ, USER_HZ);
960
961 return 0;
962 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
963 /* strange ..., for backward compatibility */
964 return sfp->timeout_user;
965 case SG_SET_FORCE_LOW_DMA:
966 /*
967 * N.B. This ioctl never worked properly, but failed to
968 * return an error value. So returning '0' to keep compability
969 * with legacy applications.
970 */
971 return 0;
972 case SG_GET_LOW_DMA:
973 return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
974 case SG_GET_SCSI_ID:
975 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
976 return -EFAULT;
977 else {
978 sg_scsi_id_t __user *sg_idp = p;
979
980 if (atomic_read(&sdp->detaching))
981 return -ENODEV;
982 __put_user((int) sdp->device->host->host_no,
983 &sg_idp->host_no);
984 __put_user((int) sdp->device->channel,
985 &sg_idp->channel);
986 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
987 __put_user((int) sdp->device->lun, &sg_idp->lun);
988 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
989 __put_user((short) sdp->device->host->cmd_per_lun,
990 &sg_idp->h_cmd_per_lun);
991 __put_user((short) sdp->device->queue_depth,
992 &sg_idp->d_queue_depth);
993 __put_user(0, &sg_idp->unused[0]);
994 __put_user(0, &sg_idp->unused[1]);
995 return 0;
996 }
997 case SG_SET_FORCE_PACK_ID:
998 result = get_user(val, ip);
999 if (result)
1000 return result;
1001 sfp->force_packid = val ? 1 : 0;
1002 return 0;
1003 case SG_GET_PACK_ID:
1004 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
1005 return -EFAULT;
1006 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1007 list_for_each_entry(srp, &sfp->rq_list, entry) {
1008 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1009 read_unlock_irqrestore(&sfp->rq_list_lock,
1010 iflags);
1011 __put_user(srp->header.pack_id, ip);
1012 return 0;
1013 }
1014 }
1015 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1016 __put_user(-1, ip);
1017 return 0;
1018 case SG_GET_NUM_WAITING:
1019 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1020 val = 0;
1021 list_for_each_entry(srp, &sfp->rq_list, entry) {
1022 if ((1 == srp->done) && (!srp->sg_io_owned))
1023 ++val;
1024 }
1025 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1026 return put_user(val, ip);
1027 case SG_GET_SG_TABLESIZE:
1028 return put_user(sdp->sg_tablesize, ip);
1029 case SG_SET_RESERVED_SIZE:
1030 result = get_user(val, ip);
1031 if (result)
1032 return result;
1033 if (val < 0)
1034 return -EINVAL;
1035 val = min_t(int, val,
1036 max_sectors_bytes(sdp->device->request_queue));
1037 mutex_lock(&sfp->f_mutex);
1038 if (val != sfp->reserve.bufflen) {
1039 if (sfp->mmap_called ||
1040 sfp->res_in_use) {
1041 mutex_unlock(&sfp->f_mutex);
1042 return -EBUSY;
1043 }
1044
1045 sg_remove_scat(sfp, &sfp->reserve);
1046 sg_build_reserve(sfp, val);
1047 }
1048 mutex_unlock(&sfp->f_mutex);
1049 return 0;
1050 case SG_GET_RESERVED_SIZE:
1051 val = min_t(int, sfp->reserve.bufflen,
1052 max_sectors_bytes(sdp->device->request_queue));
1053 return put_user(val, ip);
1054 case SG_SET_COMMAND_Q:
1055 result = get_user(val, ip);
1056 if (result)
1057 return result;
1058 sfp->cmd_q = val ? 1 : 0;
1059 return 0;
1060 case SG_GET_COMMAND_Q:
1061 return put_user((int) sfp->cmd_q, ip);
1062 case SG_SET_KEEP_ORPHAN:
1063 result = get_user(val, ip);
1064 if (result)
1065 return result;
1066 sfp->keep_orphan = val;
1067 return 0;
1068 case SG_GET_KEEP_ORPHAN:
1069 return put_user((int) sfp->keep_orphan, ip);
1070 case SG_NEXT_CMD_LEN:
1071 result = get_user(val, ip);
1072 if (result)
1073 return result;
1074 if (val > SG_MAX_CDB_SIZE)
1075 return -ENOMEM;
1076 sfp->next_cmd_len = (val > 0) ? val : 0;
1077 return 0;
1078 case SG_GET_VERSION_NUM:
1079 return put_user(sg_version_num, ip);
1080 case SG_GET_ACCESS_COUNT:
1081 /* faked - we don't have a real access count anymore */
1082 val = (sdp->device ? 1 : 0);
1083 return put_user(val, ip);
1084 case SG_GET_REQUEST_TABLE:
1085 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
1086 return -EFAULT;
1087 else {
1088 sg_req_info_t *rinfo;
1089
1090 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,
1091 GFP_KERNEL);
1092 if (!rinfo)
1093 return -ENOMEM;
1094 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1095 sg_fill_request_table(sfp, rinfo);
1096 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1097 result = __copy_to_user(p, rinfo,
1098 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1099 result = result ? -EFAULT : 0;
1100 kfree(rinfo);
1101 return result;
1102 }
1103 case SG_EMULATED_HOST:
1104 if (atomic_read(&sdp->detaching))
1105 return -ENODEV;
1106 return put_user(sdp->device->host->hostt->emulated, ip);
1107 case SCSI_IOCTL_SEND_COMMAND:
1108 if (atomic_read(&sdp->detaching))
1109 return -ENODEV;
1110 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1111 case SG_SET_DEBUG:
1112 result = get_user(val, ip);
1113 if (result)
1114 return result;
1115 sdp->sgdebug = (char) val;
1116 return 0;
1117 case BLKSECTGET:
1118 return put_user(max_sectors_bytes(sdp->device->request_queue),
1119 ip);
1120 case BLKTRACESETUP:
1121 return blk_trace_setup(sdp->device->request_queue,
1122 sdp->disk->disk_name,
1123 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1124 NULL, p);
1125 case BLKTRACESTART:
1126 return blk_trace_startstop(sdp->device->request_queue, 1);
1127 case BLKTRACESTOP:
1128 return blk_trace_startstop(sdp->device->request_queue, 0);
1129 case BLKTRACETEARDOWN:
1130 return blk_trace_remove(sdp->device->request_queue);
1131 case SCSI_IOCTL_GET_IDLUN:
1132 case SCSI_IOCTL_GET_BUS_NUMBER:
1133 case SCSI_IOCTL_PROBE_HOST:
1134 case SG_GET_TRANSFORM:
1135 case SG_SCSI_RESET:
1136 if (atomic_read(&sdp->detaching))
1137 return -ENODEV;
1138 break;
1139 default:
1140 if (read_only)
1141 return -EPERM; /* don't know so take safe approach */
1142 break;
1143 }
1144
1145 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1146 cmd_in, filp->f_flags & O_NDELAY);
1147 if (result)
1148 return result;
1149 return scsi_ioctl(sdp->device, cmd_in, p);
1150 }
1151
1152 #ifdef CONFIG_COMPAT
1153 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1154 {
1155 Sg_device *sdp;
1156 Sg_fd *sfp;
1157 struct scsi_device *sdev;
1158
1159 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1160 return -ENXIO;
1161
1162 sdev = sdp->device;
1163 if (sdev->host->hostt->compat_ioctl) {
1164 int ret;
1165
1166 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1167
1168 return ret;
1169 }
1170
1171 return -ENOIOCTLCMD;
1172 }
1173 #endif
1174
1175 static __poll_t
1176 sg_poll(struct file *filp, poll_table * wait)
1177 {
1178 __poll_t res = 0;
1179 Sg_device *sdp;
1180 Sg_fd *sfp;
1181 Sg_request *srp;
1182 int count = 0;
1183 unsigned long iflags;
1184
1185 sfp = filp->private_data;
1186 if (!sfp)
1187 return EPOLLERR;
1188 sdp = sfp->parentdp;
1189 if (!sdp)
1190 return EPOLLERR;
1191 poll_wait(filp, &sfp->read_wait, wait);
1192 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1193 list_for_each_entry(srp, &sfp->rq_list, entry) {
1194 /* if any read waiting, flag it */
1195 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1196 res = EPOLLIN | EPOLLRDNORM;
1197 ++count;
1198 }
1199 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1200
1201 if (atomic_read(&sdp->detaching))
1202 res |= EPOLLHUP;
1203 else if (!sfp->cmd_q) {
1204 if (0 == count)
1205 res |= EPOLLOUT | EPOLLWRNORM;
1206 } else if (count < SG_MAX_QUEUE)
1207 res |= EPOLLOUT | EPOLLWRNORM;
1208 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1209 "sg_poll: res=0x%x\n", (__force u32) res));
1210 return res;
1211 }
1212
1213 static int
1214 sg_fasync(int fd, struct file *filp, int mode)
1215 {
1216 Sg_device *sdp;
1217 Sg_fd *sfp;
1218
1219 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1220 return -ENXIO;
1221 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1222 "sg_fasync: mode=%d\n", mode));
1223
1224 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1225 }
1226
1227 static vm_fault_t
1228 sg_vma_fault(struct vm_fault *vmf)
1229 {
1230 struct vm_area_struct *vma = vmf->vma;
1231 Sg_fd *sfp;
1232 unsigned long offset, len, sa;
1233 Sg_scatter_hold *rsv_schp;
1234 int k, length;
1235
1236 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1237 return VM_FAULT_SIGBUS;
1238 rsv_schp = &sfp->reserve;
1239 offset = vmf->pgoff << PAGE_SHIFT;
1240 if (offset >= rsv_schp->bufflen)
1241 return VM_FAULT_SIGBUS;
1242 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1243 "sg_vma_fault: offset=%lu, scatg=%d\n",
1244 offset, rsv_schp->k_use_sg));
1245 sa = vma->vm_start;
1246 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1247 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1248 len = vma->vm_end - sa;
1249 len = (len < length) ? len : length;
1250 if (offset < len) {
1251 struct page *page = nth_page(rsv_schp->pages[k],
1252 offset >> PAGE_SHIFT);
1253 get_page(page); /* increment page count */
1254 vmf->page = page;
1255 return 0; /* success */
1256 }
1257 sa += len;
1258 offset -= len;
1259 }
1260
1261 return VM_FAULT_SIGBUS;
1262 }
1263
1264 static const struct vm_operations_struct sg_mmap_vm_ops = {
1265 .fault = sg_vma_fault,
1266 };
1267
1268 static int
1269 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1270 {
1271 Sg_fd *sfp;
1272 unsigned long req_sz, len, sa;
1273 Sg_scatter_hold *rsv_schp;
1274 int k, length;
1275 int ret = 0;
1276
1277 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1278 return -ENXIO;
1279 req_sz = vma->vm_end - vma->vm_start;
1280 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1281 "sg_mmap starting, vm_start=%p, len=%d\n",
1282 (void *) vma->vm_start, (int) req_sz));
1283 if (vma->vm_pgoff)
1284 return -EINVAL; /* want no offset */
1285 rsv_schp = &sfp->reserve;
1286 mutex_lock(&sfp->f_mutex);
1287 if (req_sz > rsv_schp->bufflen) {
1288 ret = -ENOMEM; /* cannot map more than reserved buffer */
1289 goto out;
1290 }
1291
1292 sa = vma->vm_start;
1293 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1294 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1295 len = vma->vm_end - sa;
1296 len = (len < length) ? len : length;
1297 sa += len;
1298 }
1299
1300 sfp->mmap_called = 1;
1301 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1302 vma->vm_private_data = sfp;
1303 vma->vm_ops = &sg_mmap_vm_ops;
1304 out:
1305 mutex_unlock(&sfp->f_mutex);
1306 return ret;
1307 }
1308
1309 static void
1310 sg_rq_end_io_usercontext(struct work_struct *work)
1311 {
1312 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1313 struct sg_fd *sfp = srp->parentfp;
1314
1315 sg_finish_rem_req(srp);
1316 sg_remove_request(sfp, srp);
1317 kref_put(&sfp->f_ref, sg_remove_sfp);
1318 }
1319
1320 /*
1321 * This function is a "bottom half" handler that is called by the mid
1322 * level when a command is completed (or has failed).
1323 */
1324 static void
1325 sg_rq_end_io(struct request *rq, blk_status_t status)
1326 {
1327 struct sg_request *srp = rq->end_io_data;
1328 struct scsi_request *req = scsi_req(rq);
1329 Sg_device *sdp;
1330 Sg_fd *sfp;
1331 unsigned long iflags;
1332 unsigned int ms;
1333 char *sense;
1334 int result, resid, done = 1;
1335
1336 if (WARN_ON(srp->done != 0))
1337 return;
1338
1339 sfp = srp->parentfp;
1340 if (WARN_ON(sfp == NULL))
1341 return;
1342
1343 sdp = sfp->parentdp;
1344 if (unlikely(atomic_read(&sdp->detaching)))
1345 pr_info("%s: device detaching\n", __func__);
1346
1347 sense = req->sense;
1348 result = req->result;
1349 resid = req->resid_len;
1350
1351 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1352 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1353 srp->header.pack_id, result));
1354 srp->header.resid = resid;
1355 ms = jiffies_to_msecs(jiffies);
1356 srp->header.duration = (ms > srp->header.duration) ?
1357 (ms - srp->header.duration) : 0;
1358 if (0 != result) {
1359 struct scsi_sense_hdr sshdr;
1360
1361 srp->header.status = 0xff & result;
1362 srp->header.masked_status = status_byte(result);
1363 srp->header.msg_status = msg_byte(result);
1364 srp->header.host_status = host_byte(result);
1365 srp->header.driver_status = driver_byte(result);
1366 if ((sdp->sgdebug > 0) &&
1367 ((CHECK_CONDITION == srp->header.masked_status) ||
1368 (COMMAND_TERMINATED == srp->header.masked_status)))
1369 __scsi_print_sense(sdp->device, __func__, sense,
1370 SCSI_SENSE_BUFFERSIZE);
1371
1372 /* Following if statement is a patch supplied by Eric Youngdale */
1373 if (driver_byte(result) != 0
1374 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1375 && !scsi_sense_is_deferred(&sshdr)
1376 && sshdr.sense_key == UNIT_ATTENTION
1377 && sdp->device->removable) {
1378 /* Detected possible disc change. Set the bit - this */
1379 /* may be used if there are filesystems using this device */
1380 sdp->device->changed = 1;
1381 }
1382 }
1383
1384 if (req->sense_len)
1385 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1386
1387 /* Rely on write phase to clean out srp status values, so no "else" */
1388
1389 /*
1390 * Free the request as soon as it is complete so that its resources
1391 * can be reused without waiting for userspace to read() the
1392 * result. But keep the associated bio (if any) around until
1393 * blk_rq_unmap_user() can be called from user context.
1394 */
1395 srp->rq = NULL;
1396 scsi_req_free_cmd(scsi_req(rq));
1397 __blk_put_request(rq->q, rq);
1398
1399 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1400 if (unlikely(srp->orphan)) {
1401 if (sfp->keep_orphan)
1402 srp->sg_io_owned = 0;
1403 else
1404 done = 0;
1405 }
1406 srp->done = done;
1407 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1408
1409 if (likely(done)) {
1410 /* Now wake up any sg_read() that is waiting for this
1411 * packet.
1412 */
1413 wake_up_interruptible(&sfp->read_wait);
1414 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1415 kref_put(&sfp->f_ref, sg_remove_sfp);
1416 } else {
1417 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1418 schedule_work(&srp->ew.work);
1419 }
1420 }
1421
1422 static const struct file_operations sg_fops = {
1423 .owner = THIS_MODULE,
1424 .read = sg_read,
1425 .write = sg_write,
1426 .poll = sg_poll,
1427 .unlocked_ioctl = sg_ioctl,
1428 #ifdef CONFIG_COMPAT
1429 .compat_ioctl = sg_compat_ioctl,
1430 #endif
1431 .open = sg_open,
1432 .mmap = sg_mmap,
1433 .release = sg_release,
1434 .fasync = sg_fasync,
1435 .llseek = no_llseek,
1436 };
1437
1438 static struct class *sg_sysfs_class;
1439
1440 static int sg_sysfs_valid = 0;
1441
1442 static Sg_device *
1443 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1444 {
1445 struct request_queue *q = scsidp->request_queue;
1446 Sg_device *sdp;
1447 unsigned long iflags;
1448 int error;
1449 u32 k;
1450
1451 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1452 if (!sdp) {
1453 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1454 "failure\n", __func__);
1455 return ERR_PTR(-ENOMEM);
1456 }
1457
1458 idr_preload(GFP_KERNEL);
1459 write_lock_irqsave(&sg_index_lock, iflags);
1460
1461 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1462 if (error < 0) {
1463 if (error == -ENOSPC) {
1464 sdev_printk(KERN_WARNING, scsidp,
1465 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1466 scsidp->type, SG_MAX_DEVS - 1);
1467 error = -ENODEV;
1468 } else {
1469 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1470 "allocation Sg_device failure: %d\n",
1471 __func__, error);
1472 }
1473 goto out_unlock;
1474 }
1475 k = error;
1476
1477 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1478 "sg_alloc: dev=%d \n", k));
1479 sprintf(disk->disk_name, "sg%d", k);
1480 disk->first_minor = k;
1481 sdp->disk = disk;
1482 sdp->device = scsidp;
1483 mutex_init(&sdp->open_rel_lock);
1484 INIT_LIST_HEAD(&sdp->sfds);
1485 init_waitqueue_head(&sdp->open_wait);
1486 atomic_set(&sdp->detaching, 0);
1487 rwlock_init(&sdp->sfd_lock);
1488 sdp->sg_tablesize = queue_max_segments(q);
1489 sdp->index = k;
1490 kref_init(&sdp->d_ref);
1491 error = 0;
1492
1493 out_unlock:
1494 write_unlock_irqrestore(&sg_index_lock, iflags);
1495 idr_preload_end();
1496
1497 if (error) {
1498 kfree(sdp);
1499 return ERR_PTR(error);
1500 }
1501 return sdp;
1502 }
1503
1504 static int
1505 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1506 {
1507 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1508 struct gendisk *disk;
1509 Sg_device *sdp = NULL;
1510 struct cdev * cdev = NULL;
1511 int error;
1512 unsigned long iflags;
1513
1514 disk = alloc_disk(1);
1515 if (!disk) {
1516 pr_warn("%s: alloc_disk failed\n", __func__);
1517 return -ENOMEM;
1518 }
1519 disk->major = SCSI_GENERIC_MAJOR;
1520
1521 error = -ENOMEM;
1522 cdev = cdev_alloc();
1523 if (!cdev) {
1524 pr_warn("%s: cdev_alloc failed\n", __func__);
1525 goto out;
1526 }
1527 cdev->owner = THIS_MODULE;
1528 cdev->ops = &sg_fops;
1529
1530 sdp = sg_alloc(disk, scsidp);
1531 if (IS_ERR(sdp)) {
1532 pr_warn("%s: sg_alloc failed\n", __func__);
1533 error = PTR_ERR(sdp);
1534 goto out;
1535 }
1536
1537 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1538 if (error)
1539 goto cdev_add_err;
1540
1541 sdp->cdev = cdev;
1542 if (sg_sysfs_valid) {
1543 struct device *sg_class_member;
1544
1545 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1546 MKDEV(SCSI_GENERIC_MAJOR,
1547 sdp->index),
1548 sdp, "%s", disk->disk_name);
1549 if (IS_ERR(sg_class_member)) {
1550 pr_err("%s: device_create failed\n", __func__);
1551 error = PTR_ERR(sg_class_member);
1552 goto cdev_add_err;
1553 }
1554 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1555 &sg_class_member->kobj, "generic");
1556 if (error)
1557 pr_err("%s: unable to make symlink 'generic' back "
1558 "to sg%d\n", __func__, sdp->index);
1559 } else
1560 pr_warn("%s: sg_sys Invalid\n", __func__);
1561
1562 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1563 "type %d\n", sdp->index, scsidp->type);
1564
1565 dev_set_drvdata(cl_dev, sdp);
1566
1567 return 0;
1568
1569 cdev_add_err:
1570 write_lock_irqsave(&sg_index_lock, iflags);
1571 idr_remove(&sg_index_idr, sdp->index);
1572 write_unlock_irqrestore(&sg_index_lock, iflags);
1573 kfree(sdp);
1574
1575 out:
1576 put_disk(disk);
1577 if (cdev)
1578 cdev_del(cdev);
1579 return error;
1580 }
1581
1582 static void
1583 sg_device_destroy(struct kref *kref)
1584 {
1585 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1586 unsigned long flags;
1587
1588 /* CAUTION! Note that the device can still be found via idr_find()
1589 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1590 * any other cleanup.
1591 */
1592
1593 write_lock_irqsave(&sg_index_lock, flags);
1594 idr_remove(&sg_index_idr, sdp->index);
1595 write_unlock_irqrestore(&sg_index_lock, flags);
1596
1597 SCSI_LOG_TIMEOUT(3,
1598 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1599
1600 put_disk(sdp->disk);
1601 kfree(sdp);
1602 }
1603
1604 static void
1605 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1606 {
1607 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1608 Sg_device *sdp = dev_get_drvdata(cl_dev);
1609 unsigned long iflags;
1610 Sg_fd *sfp;
1611 int val;
1612
1613 if (!sdp)
1614 return;
1615 /* want sdp->detaching non-zero as soon as possible */
1616 val = atomic_inc_return(&sdp->detaching);
1617 if (val > 1)
1618 return; /* only want to do following once per device */
1619
1620 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1621 "%s\n", __func__));
1622
1623 read_lock_irqsave(&sdp->sfd_lock, iflags);
1624 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1625 wake_up_interruptible_all(&sfp->read_wait);
1626 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1627 }
1628 wake_up_interruptible_all(&sdp->open_wait);
1629 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1630
1631 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1632 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1633 cdev_del(sdp->cdev);
1634 sdp->cdev = NULL;
1635
1636 kref_put(&sdp->d_ref, sg_device_destroy);
1637 }
1638
1639 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1640 module_param_named(def_reserved_size, def_reserved_size, int,
1641 S_IRUGO | S_IWUSR);
1642 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1643
1644 MODULE_AUTHOR("Douglas Gilbert");
1645 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1646 MODULE_LICENSE("GPL");
1647 MODULE_VERSION(SG_VERSION_STR);
1648 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1649
1650 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1651 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1652 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1653 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1654
1655 static int __init
1656 init_sg(void)
1657 {
1658 int rc;
1659
1660 if (scatter_elem_sz < PAGE_SIZE) {
1661 scatter_elem_sz = PAGE_SIZE;
1662 scatter_elem_sz_prev = scatter_elem_sz;
1663 }
1664 if (def_reserved_size >= 0)
1665 sg_big_buff = def_reserved_size;
1666 else
1667 def_reserved_size = sg_big_buff;
1668
1669 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1670 SG_MAX_DEVS, "sg");
1671 if (rc)
1672 return rc;
1673 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1674 if ( IS_ERR(sg_sysfs_class) ) {
1675 rc = PTR_ERR(sg_sysfs_class);
1676 goto err_out;
1677 }
1678 sg_sysfs_valid = 1;
1679 rc = scsi_register_interface(&sg_interface);
1680 if (0 == rc) {
1681 #ifdef CONFIG_SCSI_PROC_FS
1682 sg_proc_init();
1683 #endif /* CONFIG_SCSI_PROC_FS */
1684 return 0;
1685 }
1686 class_destroy(sg_sysfs_class);
1687 err_out:
1688 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1689 return rc;
1690 }
1691
1692 static void __exit
1693 exit_sg(void)
1694 {
1695 #ifdef CONFIG_SCSI_PROC_FS
1696 remove_proc_subtree("scsi/sg", NULL);
1697 #endif /* CONFIG_SCSI_PROC_FS */
1698 scsi_unregister_interface(&sg_interface);
1699 class_destroy(sg_sysfs_class);
1700 sg_sysfs_valid = 0;
1701 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1702 SG_MAX_DEVS);
1703 idr_destroy(&sg_index_idr);
1704 }
1705
1706 static int
1707 sg_start_req(Sg_request *srp, unsigned char *cmd)
1708 {
1709 int res;
1710 struct request *rq;
1711 struct scsi_request *req;
1712 Sg_fd *sfp = srp->parentfp;
1713 sg_io_hdr_t *hp = &srp->header;
1714 int dxfer_len = (int) hp->dxfer_len;
1715 int dxfer_dir = hp->dxfer_direction;
1716 unsigned int iov_count = hp->iovec_count;
1717 Sg_scatter_hold *req_schp = &srp->data;
1718 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1719 struct request_queue *q = sfp->parentdp->device->request_queue;
1720 struct rq_map_data *md, map_data;
1721 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1722 unsigned char *long_cmdp = NULL;
1723
1724 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1725 "sg_start_req: dxfer_len=%d\n",
1726 dxfer_len));
1727
1728 if (hp->cmd_len > BLK_MAX_CDB) {
1729 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1730 if (!long_cmdp)
1731 return -ENOMEM;
1732 }
1733
1734 /*
1735 * NOTE
1736 *
1737 * With scsi-mq enabled, there are a fixed number of preallocated
1738 * requests equal in number to shost->can_queue. If all of the
1739 * preallocated requests are already in use, then blk_get_request()
1740 * will sleep until an active command completes, freeing up a request.
1741 * Although waiting in an asynchronous interface is less than ideal, we
1742 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
1743 * not expect an EWOULDBLOCK from this condition.
1744 */
1745 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1746 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
1747 if (IS_ERR(rq)) {
1748 kfree(long_cmdp);
1749 return PTR_ERR(rq);
1750 }
1751 req = scsi_req(rq);
1752
1753 if (hp->cmd_len > BLK_MAX_CDB)
1754 req->cmd = long_cmdp;
1755 memcpy(req->cmd, cmd, hp->cmd_len);
1756 req->cmd_len = hp->cmd_len;
1757
1758 srp->rq = rq;
1759 rq->end_io_data = srp;
1760 req->retries = SG_DEFAULT_RETRIES;
1761
1762 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1763 return 0;
1764
1765 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1766 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1767 !sfp->parentdp->device->host->unchecked_isa_dma &&
1768 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1769 md = NULL;
1770 else
1771 md = &map_data;
1772
1773 if (md) {
1774 mutex_lock(&sfp->f_mutex);
1775 if (dxfer_len <= rsv_schp->bufflen &&
1776 !sfp->res_in_use) {
1777 sfp->res_in_use = 1;
1778 sg_link_reserve(sfp, srp, dxfer_len);
1779 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1780 res = -EBUSY; /* sfp->res_in_use == 1 */
1781 if (dxfer_len > rsv_schp->bufflen)
1782 res = -ENOMEM;
1783 mutex_unlock(&sfp->f_mutex);
1784 return res;
1785 } else {
1786 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1787 if (res) {
1788 mutex_unlock(&sfp->f_mutex);
1789 return res;
1790 }
1791 }
1792 mutex_unlock(&sfp->f_mutex);
1793
1794 md->pages = req_schp->pages;
1795 md->page_order = req_schp->page_order;
1796 md->nr_entries = req_schp->k_use_sg;
1797 md->offset = 0;
1798 md->null_mapped = hp->dxferp ? 0 : 1;
1799 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1800 md->from_user = 1;
1801 else
1802 md->from_user = 0;
1803 }
1804
1805 if (iov_count) {
1806 struct iovec *iov = NULL;
1807 struct iov_iter i;
1808
1809 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1810 if (res < 0)
1811 return res;
1812
1813 iov_iter_truncate(&i, hp->dxfer_len);
1814 if (!iov_iter_count(&i)) {
1815 kfree(iov);
1816 return -EINVAL;
1817 }
1818
1819 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1820 kfree(iov);
1821 } else
1822 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1823 hp->dxfer_len, GFP_ATOMIC);
1824
1825 if (!res) {
1826 srp->bio = rq->bio;
1827
1828 if (!md) {
1829 req_schp->dio_in_use = 1;
1830 hp->info |= SG_INFO_DIRECT_IO;
1831 }
1832 }
1833 return res;
1834 }
1835
1836 static int
1837 sg_finish_rem_req(Sg_request *srp)
1838 {
1839 int ret = 0;
1840
1841 Sg_fd *sfp = srp->parentfp;
1842 Sg_scatter_hold *req_schp = &srp->data;
1843
1844 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1845 "sg_finish_rem_req: res_used=%d\n",
1846 (int) srp->res_used));
1847 if (srp->bio)
1848 ret = blk_rq_unmap_user(srp->bio);
1849
1850 if (srp->rq) {
1851 scsi_req_free_cmd(scsi_req(srp->rq));
1852 blk_put_request(srp->rq);
1853 }
1854
1855 if (srp->res_used)
1856 sg_unlink_reserve(sfp, srp);
1857 else
1858 sg_remove_scat(sfp, req_schp);
1859
1860 return ret;
1861 }
1862
1863 static int
1864 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1865 {
1866 int sg_bufflen = tablesize * sizeof(struct page *);
1867 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1868
1869 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1870 if (!schp->pages)
1871 return -ENOMEM;
1872 schp->sglist_len = sg_bufflen;
1873 return tablesize; /* number of scat_gath elements allocated */
1874 }
1875
1876 static int
1877 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1878 {
1879 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1880 int sg_tablesize = sfp->parentdp->sg_tablesize;
1881 int blk_size = buff_size, order;
1882 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
1883 struct sg_device *sdp = sfp->parentdp;
1884
1885 if (blk_size < 0)
1886 return -EFAULT;
1887 if (0 == blk_size)
1888 ++blk_size; /* don't know why */
1889 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1890 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1891 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1892 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1893 buff_size, blk_size));
1894
1895 /* N.B. ret_sz carried into this block ... */
1896 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1897 if (mx_sc_elems < 0)
1898 return mx_sc_elems; /* most likely -ENOMEM */
1899
1900 num = scatter_elem_sz;
1901 if (unlikely(num != scatter_elem_sz_prev)) {
1902 if (num < PAGE_SIZE) {
1903 scatter_elem_sz = PAGE_SIZE;
1904 scatter_elem_sz_prev = PAGE_SIZE;
1905 } else
1906 scatter_elem_sz_prev = num;
1907 }
1908
1909 if (sdp->device->host->unchecked_isa_dma)
1910 gfp_mask |= GFP_DMA;
1911
1912 order = get_order(num);
1913 retry:
1914 ret_sz = 1 << (PAGE_SHIFT + order);
1915
1916 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1917 k++, rem_sz -= ret_sz) {
1918
1919 num = (rem_sz > scatter_elem_sz_prev) ?
1920 scatter_elem_sz_prev : rem_sz;
1921
1922 schp->pages[k] = alloc_pages(gfp_mask, order);
1923 if (!schp->pages[k])
1924 goto out;
1925
1926 if (num == scatter_elem_sz_prev) {
1927 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1928 scatter_elem_sz = ret_sz;
1929 scatter_elem_sz_prev = ret_sz;
1930 }
1931 }
1932
1933 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1934 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1935 k, num, ret_sz));
1936 } /* end of for loop */
1937
1938 schp->page_order = order;
1939 schp->k_use_sg = k;
1940 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1941 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1942 k, rem_sz));
1943
1944 schp->bufflen = blk_size;
1945 if (rem_sz > 0) /* must have failed */
1946 return -ENOMEM;
1947 return 0;
1948 out:
1949 for (i = 0; i < k; i++)
1950 __free_pages(schp->pages[i], order);
1951
1952 if (--order >= 0)
1953 goto retry;
1954
1955 return -ENOMEM;
1956 }
1957
1958 static void
1959 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1960 {
1961 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1962 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1963 if (schp->pages && schp->sglist_len > 0) {
1964 if (!schp->dio_in_use) {
1965 int k;
1966
1967 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1968 SCSI_LOG_TIMEOUT(5,
1969 sg_printk(KERN_INFO, sfp->parentdp,
1970 "sg_remove_scat: k=%d, pg=0x%p\n",
1971 k, schp->pages[k]));
1972 __free_pages(schp->pages[k], schp->page_order);
1973 }
1974
1975 kfree(schp->pages);
1976 }
1977 }
1978 memset(schp, 0, sizeof (*schp));
1979 }
1980
1981 static int
1982 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1983 {
1984 Sg_scatter_hold *schp = &srp->data;
1985 int k, num;
1986
1987 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1988 "sg_read_oxfer: num_read_xfer=%d\n",
1989 num_read_xfer));
1990 if ((!outp) || (num_read_xfer <= 0))
1991 return 0;
1992
1993 num = 1 << (PAGE_SHIFT + schp->page_order);
1994 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1995 if (num > num_read_xfer) {
1996 if (__copy_to_user(outp, page_address(schp->pages[k]),
1997 num_read_xfer))
1998 return -EFAULT;
1999 break;
2000 } else {
2001 if (__copy_to_user(outp, page_address(schp->pages[k]),
2002 num))
2003 return -EFAULT;
2004 num_read_xfer -= num;
2005 if (num_read_xfer <= 0)
2006 break;
2007 outp += num;
2008 }
2009 }
2010
2011 return 0;
2012 }
2013
2014 static void
2015 sg_build_reserve(Sg_fd * sfp, int req_size)
2016 {
2017 Sg_scatter_hold *schp = &sfp->reserve;
2018
2019 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2020 "sg_build_reserve: req_size=%d\n", req_size));
2021 do {
2022 if (req_size < PAGE_SIZE)
2023 req_size = PAGE_SIZE;
2024 if (0 == sg_build_indirect(schp, sfp, req_size))
2025 return;
2026 else
2027 sg_remove_scat(sfp, schp);
2028 req_size >>= 1; /* divide by 2 */
2029 } while (req_size > (PAGE_SIZE / 2));
2030 }
2031
2032 static void
2033 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2034 {
2035 Sg_scatter_hold *req_schp = &srp->data;
2036 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2037 int k, num, rem;
2038
2039 srp->res_used = 1;
2040 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2041 "sg_link_reserve: size=%d\n", size));
2042 rem = size;
2043
2044 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2045 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2046 if (rem <= num) {
2047 req_schp->k_use_sg = k + 1;
2048 req_schp->sglist_len = rsv_schp->sglist_len;
2049 req_schp->pages = rsv_schp->pages;
2050
2051 req_schp->bufflen = size;
2052 req_schp->page_order = rsv_schp->page_order;
2053 break;
2054 } else
2055 rem -= num;
2056 }
2057
2058 if (k >= rsv_schp->k_use_sg)
2059 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2060 "sg_link_reserve: BAD size\n"));
2061 }
2062
2063 static void
2064 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2065 {
2066 Sg_scatter_hold *req_schp = &srp->data;
2067
2068 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2069 "sg_unlink_reserve: req->k_use_sg=%d\n",
2070 (int) req_schp->k_use_sg));
2071 req_schp->k_use_sg = 0;
2072 req_schp->bufflen = 0;
2073 req_schp->pages = NULL;
2074 req_schp->page_order = 0;
2075 req_schp->sglist_len = 0;
2076 srp->res_used = 0;
2077 /* Called without mutex lock to avoid deadlock */
2078 sfp->res_in_use = 0;
2079 }
2080
2081 static Sg_request *
2082 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2083 {
2084 Sg_request *resp;
2085 unsigned long iflags;
2086
2087 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2088 list_for_each_entry(resp, &sfp->rq_list, entry) {
2089 /* look for requests that are ready + not SG_IO owned */
2090 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2091 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2092 resp->done = 2; /* guard against other readers */
2093 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2094 return resp;
2095 }
2096 }
2097 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2098 return NULL;
2099 }
2100
2101 /* always adds to end of list */
2102 static Sg_request *
2103 sg_add_request(Sg_fd * sfp)
2104 {
2105 int k;
2106 unsigned long iflags;
2107 Sg_request *rp = sfp->req_arr;
2108
2109 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2110 if (!list_empty(&sfp->rq_list)) {
2111 if (!sfp->cmd_q)
2112 goto out_unlock;
2113
2114 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2115 if (!rp->parentfp)
2116 break;
2117 }
2118 if (k >= SG_MAX_QUEUE)
2119 goto out_unlock;
2120 }
2121 memset(rp, 0, sizeof (Sg_request));
2122 rp->parentfp = sfp;
2123 rp->header.duration = jiffies_to_msecs(jiffies);
2124 list_add_tail(&rp->entry, &sfp->rq_list);
2125 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2126 return rp;
2127 out_unlock:
2128 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2129 return NULL;
2130 }
2131
2132 /* Return of 1 for found; 0 for not found */
2133 static int
2134 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2135 {
2136 unsigned long iflags;
2137 int res = 0;
2138
2139 if (!sfp || !srp || list_empty(&sfp->rq_list))
2140 return res;
2141 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2142 if (!list_empty(&srp->entry)) {
2143 list_del(&srp->entry);
2144 srp->parentfp = NULL;
2145 res = 1;
2146 }
2147 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2148 return res;
2149 }
2150
2151 static Sg_fd *
2152 sg_add_sfp(Sg_device * sdp)
2153 {
2154 Sg_fd *sfp;
2155 unsigned long iflags;
2156 int bufflen;
2157
2158 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2159 if (!sfp)
2160 return ERR_PTR(-ENOMEM);
2161
2162 init_waitqueue_head(&sfp->read_wait);
2163 rwlock_init(&sfp->rq_list_lock);
2164 INIT_LIST_HEAD(&sfp->rq_list);
2165 kref_init(&sfp->f_ref);
2166 mutex_init(&sfp->f_mutex);
2167 sfp->timeout = SG_DEFAULT_TIMEOUT;
2168 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2169 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2170 sfp->cmd_q = SG_DEF_COMMAND_Q;
2171 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2172 sfp->parentdp = sdp;
2173 write_lock_irqsave(&sdp->sfd_lock, iflags);
2174 if (atomic_read(&sdp->detaching)) {
2175 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2176 kfree(sfp);
2177 return ERR_PTR(-ENODEV);
2178 }
2179 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2180 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2181 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2182 "sg_add_sfp: sfp=0x%p\n", sfp));
2183 if (unlikely(sg_big_buff != def_reserved_size))
2184 sg_big_buff = def_reserved_size;
2185
2186 bufflen = min_t(int, sg_big_buff,
2187 max_sectors_bytes(sdp->device->request_queue));
2188 sg_build_reserve(sfp, bufflen);
2189 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2190 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2191 sfp->reserve.bufflen,
2192 sfp->reserve.k_use_sg));
2193
2194 kref_get(&sdp->d_ref);
2195 __module_get(THIS_MODULE);
2196 return sfp;
2197 }
2198
2199 static void
2200 sg_remove_sfp_usercontext(struct work_struct *work)
2201 {
2202 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2203 struct sg_device *sdp = sfp->parentdp;
2204 Sg_request *srp;
2205 unsigned long iflags;
2206
2207 /* Cleanup any responses which were never read(). */
2208 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2209 while (!list_empty(&sfp->rq_list)) {
2210 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2211 sg_finish_rem_req(srp);
2212 list_del(&srp->entry);
2213 srp->parentfp = NULL;
2214 }
2215 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2216
2217 if (sfp->reserve.bufflen > 0) {
2218 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2219 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2220 (int) sfp->reserve.bufflen,
2221 (int) sfp->reserve.k_use_sg));
2222 sg_remove_scat(sfp, &sfp->reserve);
2223 }
2224
2225 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2226 "sg_remove_sfp: sfp=0x%p\n", sfp));
2227 kfree(sfp);
2228
2229 scsi_device_put(sdp->device);
2230 kref_put(&sdp->d_ref, sg_device_destroy);
2231 module_put(THIS_MODULE);
2232 }
2233
2234 static void
2235 sg_remove_sfp(struct kref *kref)
2236 {
2237 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2238 struct sg_device *sdp = sfp->parentdp;
2239 unsigned long iflags;
2240
2241 write_lock_irqsave(&sdp->sfd_lock, iflags);
2242 list_del(&sfp->sfd_siblings);
2243 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2244
2245 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2246 schedule_work(&sfp->ew.work);
2247 }
2248
2249 #ifdef CONFIG_SCSI_PROC_FS
2250 static int
2251 sg_idr_max_id(int id, void *p, void *data)
2252 {
2253 int *k = data;
2254
2255 if (*k < id)
2256 *k = id;
2257
2258 return 0;
2259 }
2260
2261 static int
2262 sg_last_dev(void)
2263 {
2264 int k = -1;
2265 unsigned long iflags;
2266
2267 read_lock_irqsave(&sg_index_lock, iflags);
2268 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2269 read_unlock_irqrestore(&sg_index_lock, iflags);
2270 return k + 1; /* origin 1 */
2271 }
2272 #endif
2273
2274 /* must be called with sg_index_lock held */
2275 static Sg_device *sg_lookup_dev(int dev)
2276 {
2277 return idr_find(&sg_index_idr, dev);
2278 }
2279
2280 static Sg_device *
2281 sg_get_dev(int dev)
2282 {
2283 struct sg_device *sdp;
2284 unsigned long flags;
2285
2286 read_lock_irqsave(&sg_index_lock, flags);
2287 sdp = sg_lookup_dev(dev);
2288 if (!sdp)
2289 sdp = ERR_PTR(-ENXIO);
2290 else if (atomic_read(&sdp->detaching)) {
2291 /* If sdp->detaching, then the refcount may already be 0, in
2292 * which case it would be a bug to do kref_get().
2293 */
2294 sdp = ERR_PTR(-ENODEV);
2295 } else
2296 kref_get(&sdp->d_ref);
2297 read_unlock_irqrestore(&sg_index_lock, flags);
2298
2299 return sdp;
2300 }
2301
2302 #ifdef CONFIG_SCSI_PROC_FS
2303 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2304
2305 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2306 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2307 size_t count, loff_t *off);
2308 static const struct file_operations adio_fops = {
2309 .owner = THIS_MODULE,
2310 .open = sg_proc_single_open_adio,
2311 .read = seq_read,
2312 .llseek = seq_lseek,
2313 .write = sg_proc_write_adio,
2314 .release = single_release,
2315 };
2316
2317 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2318 static ssize_t sg_proc_write_dressz(struct file *filp,
2319 const char __user *buffer, size_t count, loff_t *off);
2320 static const struct file_operations dressz_fops = {
2321 .owner = THIS_MODULE,
2322 .open = sg_proc_single_open_dressz,
2323 .read = seq_read,
2324 .llseek = seq_lseek,
2325 .write = sg_proc_write_dressz,
2326 .release = single_release,
2327 };
2328
2329 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2330 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2331 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2332 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2333 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2334 static void dev_seq_stop(struct seq_file *s, void *v);
2335 static const struct seq_operations dev_seq_ops = {
2336 .start = dev_seq_start,
2337 .next = dev_seq_next,
2338 .stop = dev_seq_stop,
2339 .show = sg_proc_seq_show_dev,
2340 };
2341
2342 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2343 static const struct seq_operations devstrs_seq_ops = {
2344 .start = dev_seq_start,
2345 .next = dev_seq_next,
2346 .stop = dev_seq_stop,
2347 .show = sg_proc_seq_show_devstrs,
2348 };
2349
2350 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2351 static const struct seq_operations debug_seq_ops = {
2352 .start = dev_seq_start,
2353 .next = dev_seq_next,
2354 .stop = dev_seq_stop,
2355 .show = sg_proc_seq_show_debug,
2356 };
2357
2358 static int
2359 sg_proc_init(void)
2360 {
2361 struct proc_dir_entry *p;
2362
2363 p = proc_mkdir("scsi/sg", NULL);
2364 if (!p)
2365 return 1;
2366
2367 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_fops);
2368 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);
2369 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_fops);
2370 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr);
2371 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops);
2372 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops);
2373 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version);
2374 return 0;
2375 }
2376
2377
2378 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2379 {
2380 seq_printf(s, "%d\n", *((int *)s->private));
2381 return 0;
2382 }
2383
2384 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2385 {
2386 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2387 }
2388
2389 static ssize_t
2390 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2391 size_t count, loff_t *off)
2392 {
2393 int err;
2394 unsigned long num;
2395
2396 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2397 return -EACCES;
2398 err = kstrtoul_from_user(buffer, count, 0, &num);
2399 if (err)
2400 return err;
2401 sg_allow_dio = num ? 1 : 0;
2402 return count;
2403 }
2404
2405 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2406 {
2407 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2408 }
2409
2410 static ssize_t
2411 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2412 size_t count, loff_t *off)
2413 {
2414 int err;
2415 unsigned long k = ULONG_MAX;
2416
2417 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2418 return -EACCES;
2419
2420 err = kstrtoul_from_user(buffer, count, 0, &k);
2421 if (err)
2422 return err;
2423 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2424 sg_big_buff = k;
2425 return count;
2426 }
2427 return -ERANGE;
2428 }
2429
2430 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2431 {
2432 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2433 sg_version_date);
2434 return 0;
2435 }
2436
2437 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2438 {
2439 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2440 return 0;
2441 }
2442
2443 struct sg_proc_deviter {
2444 loff_t index;
2445 size_t max;
2446 };
2447
2448 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2449 {
2450 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2451
2452 s->private = it;
2453 if (! it)
2454 return NULL;
2455
2456 it->index = *pos;
2457 it->max = sg_last_dev();
2458 if (it->index >= it->max)
2459 return NULL;
2460 return it;
2461 }
2462
2463 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2464 {
2465 struct sg_proc_deviter * it = s->private;
2466
2467 *pos = ++it->index;
2468 return (it->index < it->max) ? it : NULL;
2469 }
2470
2471 static void dev_seq_stop(struct seq_file *s, void *v)
2472 {
2473 kfree(s->private);
2474 }
2475
2476 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2477 {
2478 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2479 Sg_device *sdp;
2480 struct scsi_device *scsidp;
2481 unsigned long iflags;
2482
2483 read_lock_irqsave(&sg_index_lock, iflags);
2484 sdp = it ? sg_lookup_dev(it->index) : NULL;
2485 if ((NULL == sdp) || (NULL == sdp->device) ||
2486 (atomic_read(&sdp->detaching)))
2487 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2488 else {
2489 scsidp = sdp->device;
2490 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2491 scsidp->host->host_no, scsidp->channel,
2492 scsidp->id, scsidp->lun, (int) scsidp->type,
2493 1,
2494 (int) scsidp->queue_depth,
2495 (int) atomic_read(&scsidp->device_busy),
2496 (int) scsi_device_online(scsidp));
2497 }
2498 read_unlock_irqrestore(&sg_index_lock, iflags);
2499 return 0;
2500 }
2501
2502 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2503 {
2504 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2505 Sg_device *sdp;
2506 struct scsi_device *scsidp;
2507 unsigned long iflags;
2508
2509 read_lock_irqsave(&sg_index_lock, iflags);
2510 sdp = it ? sg_lookup_dev(it->index) : NULL;
2511 scsidp = sdp ? sdp->device : NULL;
2512 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2513 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2514 scsidp->vendor, scsidp->model, scsidp->rev);
2515 else
2516 seq_puts(s, "<no active device>\n");
2517 read_unlock_irqrestore(&sg_index_lock, iflags);
2518 return 0;
2519 }
2520
2521 /* must be called while holding sg_index_lock */
2522 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2523 {
2524 int k, new_interface, blen, usg;
2525 Sg_request *srp;
2526 Sg_fd *fp;
2527 const sg_io_hdr_t *hp;
2528 const char * cp;
2529 unsigned int ms;
2530
2531 k = 0;
2532 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2533 k++;
2534 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2535 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2536 "(res)sgat=%d low_dma=%d\n", k,
2537 jiffies_to_msecs(fp->timeout),
2538 fp->reserve.bufflen,
2539 (int) fp->reserve.k_use_sg,
2540 (int) sdp->device->host->unchecked_isa_dma);
2541 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2542 (int) fp->cmd_q, (int) fp->force_packid,
2543 (int) fp->keep_orphan);
2544 list_for_each_entry(srp, &fp->rq_list, entry) {
2545 hp = &srp->header;
2546 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2547 if (srp->res_used) {
2548 if (new_interface &&
2549 (SG_FLAG_MMAP_IO & hp->flags))
2550 cp = " mmap>> ";
2551 else
2552 cp = " rb>> ";
2553 } else {
2554 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2555 cp = " dio>> ";
2556 else
2557 cp = " ";
2558 }
2559 seq_puts(s, cp);
2560 blen = srp->data.bufflen;
2561 usg = srp->data.k_use_sg;
2562 seq_puts(s, srp->done ?
2563 ((1 == srp->done) ? "rcv:" : "fin:")
2564 : "act:");
2565 seq_printf(s, " id=%d blen=%d",
2566 srp->header.pack_id, blen);
2567 if (srp->done)
2568 seq_printf(s, " dur=%d", hp->duration);
2569 else {
2570 ms = jiffies_to_msecs(jiffies);
2571 seq_printf(s, " t_o/elap=%d/%d",
2572 (new_interface ? hp->timeout :
2573 jiffies_to_msecs(fp->timeout)),
2574 (ms > hp->duration ? ms - hp->duration : 0));
2575 }
2576 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2577 (int) srp->data.cmd_opcode);
2578 }
2579 if (list_empty(&fp->rq_list))
2580 seq_puts(s, " No requests active\n");
2581 read_unlock(&fp->rq_list_lock);
2582 }
2583 }
2584
2585 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2586 {
2587 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2588 Sg_device *sdp;
2589 unsigned long iflags;
2590
2591 if (it && (0 == it->index))
2592 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2593 (int)it->max, sg_big_buff);
2594
2595 read_lock_irqsave(&sg_index_lock, iflags);
2596 sdp = it ? sg_lookup_dev(it->index) : NULL;
2597 if (NULL == sdp)
2598 goto skip;
2599 read_lock(&sdp->sfd_lock);
2600 if (!list_empty(&sdp->sfds)) {
2601 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2602 if (atomic_read(&sdp->detaching))
2603 seq_puts(s, "detaching pending close ");
2604 else if (sdp->device) {
2605 struct scsi_device *scsidp = sdp->device;
2606
2607 seq_printf(s, "%d:%d:%d:%llu em=%d",
2608 scsidp->host->host_no,
2609 scsidp->channel, scsidp->id,
2610 scsidp->lun,
2611 scsidp->host->hostt->emulated);
2612 }
2613 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2614 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2615 sg_proc_debug_helper(s, sdp);
2616 }
2617 read_unlock(&sdp->sfd_lock);
2618 skip:
2619 read_unlock_irqrestore(&sg_index_lock, iflags);
2620 return 0;
2621 }
2622
2623 #endif /* CONFIG_SCSI_PROC_FS */
2624
2625 module_init(init_sg);
2626 module_exit(exit_sg);
Linux with added FPC-III support