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Linux 4.9.237
[linux/fpc-iii.git] / drivers / scsi / sg.c
blob417927b279b676761b86b8c1d87e8f4c124d938d
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, int uptodate);
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 (unlikely(segment_eq(get_fs(), KERNEL_DS))) {
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 & FMODE_WRITE);
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 sg_remove_request(sfp, srp);
700 return -EFAULT;
701 }
702 /*
703 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
704 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
705 * is a non-zero input_size, so emit a warning.
706 */
707 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
708 printk_ratelimited(KERN_WARNING
709 "sg_write: data in/out %d/%d bytes "
710 "for SCSI command 0x%x-- guessing "
711 "data in;\n program %s not setting "
712 "count and/or reply_len properly\n",
713 old_hdr.reply_len - (int)SZ_SG_HEADER,
714 input_size, (unsigned int) cmnd[0],
715 current->comm);
716 }
717 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
718 return (k < 0) ? k : count;
719 }
720
721 static ssize_t
722 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
723 size_t count, int blocking, int read_only, int sg_io_owned,
724 Sg_request **o_srp)
725 {
726 int k;
727 Sg_request *srp;
728 sg_io_hdr_t *hp;
729 unsigned char cmnd[SG_MAX_CDB_SIZE];
730 int timeout;
731 unsigned long ul_timeout;
732
733 if (count < SZ_SG_IO_HDR)
734 return -EINVAL;
735 if (!access_ok(VERIFY_READ, buf, count))
736 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
737
738 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
739 if (!(srp = sg_add_request(sfp))) {
740 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
741 "sg_new_write: queue full\n"));
742 return -EDOM;
743 }
744 srp->sg_io_owned = sg_io_owned;
745 hp = &srp->header;
746 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
747 sg_remove_request(sfp, srp);
748 return -EFAULT;
749 }
750 if (hp->interface_id != 'S') {
751 sg_remove_request(sfp, srp);
752 return -ENOSYS;
753 }
754 if (hp->flags & SG_FLAG_MMAP_IO) {
755 if (hp->dxfer_len > sfp->reserve.bufflen) {
756 sg_remove_request(sfp, srp);
757 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
758 }
759 if (hp->flags & SG_FLAG_DIRECT_IO) {
760 sg_remove_request(sfp, srp);
761 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
762 }
763 if (sfp->res_in_use) {
764 sg_remove_request(sfp, srp);
765 return -EBUSY; /* reserve buffer already being used */
766 }
767 }
768 ul_timeout = msecs_to_jiffies(srp->header.timeout);
769 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
770 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
771 sg_remove_request(sfp, srp);
772 return -EMSGSIZE;
773 }
774 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
775 sg_remove_request(sfp, srp);
776 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
777 }
778 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
779 sg_remove_request(sfp, srp);
780 return -EFAULT;
781 }
782 if (read_only && sg_allow_access(file, cmnd)) {
783 sg_remove_request(sfp, srp);
784 return -EPERM;
785 }
786 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
787 if (k < 0)
788 return k;
789 if (o_srp)
790 *o_srp = srp;
791 return count;
792 }
793
794 static int
795 sg_common_write(Sg_fd * sfp, Sg_request * srp,
796 unsigned char *cmnd, int timeout, int blocking)
797 {
798 int k, at_head;
799 Sg_device *sdp = sfp->parentdp;
800 sg_io_hdr_t *hp = &srp->header;
801
802 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
803 hp->status = 0;
804 hp->masked_status = 0;
805 hp->msg_status = 0;
806 hp->info = 0;
807 hp->host_status = 0;
808 hp->driver_status = 0;
809 hp->resid = 0;
810 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
811 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
812 (int) cmnd[0], (int) hp->cmd_len));
813
814 if (hp->dxfer_len >= SZ_256M) {
815 sg_remove_request(sfp, srp);
816 return -EINVAL;
817 }
818
819 k = sg_start_req(srp, cmnd);
820 if (k) {
821 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
822 "sg_common_write: start_req err=%d\n", k));
823 sg_finish_rem_req(srp);
824 sg_remove_request(sfp, srp);
825 return k; /* probably out of space --> ENOMEM */
826 }
827 if (atomic_read(&sdp->detaching)) {
828 if (srp->bio) {
829 if (srp->rq->cmd != srp->rq->__cmd)
830 kfree(srp->rq->cmd);
831
832 blk_end_request_all(srp->rq, -EIO);
833 srp->rq = NULL;
834 }
835
836 sg_finish_rem_req(srp);
837 sg_remove_request(sfp, srp);
838 return -ENODEV;
839 }
840
841 hp->duration = jiffies_to_msecs(jiffies);
842 if (hp->interface_id != '\0' && /* v3 (or later) interface */
843 (SG_FLAG_Q_AT_TAIL & hp->flags))
844 at_head = 0;
845 else
846 at_head = 1;
847
848 srp->rq->timeout = timeout;
849 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
850 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
851 srp->rq, at_head, sg_rq_end_io);
852 return 0;
853 }
854
855 static int srp_done(Sg_fd *sfp, Sg_request *srp)
856 {
857 unsigned long flags;
858 int ret;
859
860 read_lock_irqsave(&sfp->rq_list_lock, flags);
861 ret = srp->done;
862 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
863 return ret;
864 }
865
866 static int max_sectors_bytes(struct request_queue *q)
867 {
868 unsigned int max_sectors = queue_max_sectors(q);
869
870 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
871
872 return max_sectors << 9;
873 }
874
875 static void
876 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
877 {
878 Sg_request *srp;
879 int val;
880 unsigned int ms;
881
882 val = 0;
883 list_for_each_entry(srp, &sfp->rq_list, entry) {
884 if (val >= SG_MAX_QUEUE)
885 break;
886 rinfo[val].req_state = srp->done + 1;
887 rinfo[val].problem =
888 srp->header.masked_status &
889 srp->header.host_status &
890 srp->header.driver_status;
891 if (srp->done)
892 rinfo[val].duration =
893 srp->header.duration;
894 else {
895 ms = jiffies_to_msecs(jiffies);
896 rinfo[val].duration =
897 (ms > srp->header.duration) ?
898 (ms - srp->header.duration) : 0;
899 }
900 rinfo[val].orphan = srp->orphan;
901 rinfo[val].sg_io_owned = srp->sg_io_owned;
902 rinfo[val].pack_id = srp->header.pack_id;
903 rinfo[val].usr_ptr = srp->header.usr_ptr;
904 val++;
905 }
906 }
907
908 static long
909 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
910 {
911 void __user *p = (void __user *)arg;
912 int __user *ip = p;
913 int result, val, read_only;
914 Sg_device *sdp;
915 Sg_fd *sfp;
916 Sg_request *srp;
917 unsigned long iflags;
918
919 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
920 return -ENXIO;
921
922 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
923 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
924 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
925
926 switch (cmd_in) {
927 case SG_IO:
928 if (atomic_read(&sdp->detaching))
929 return -ENODEV;
930 if (!scsi_block_when_processing_errors(sdp->device))
931 return -ENXIO;
932 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
933 return -EFAULT;
934 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
935 1, read_only, 1, &srp);
936 if (result < 0)
937 return result;
938 result = wait_event_interruptible(sfp->read_wait,
939 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
940 if (atomic_read(&sdp->detaching))
941 return -ENODEV;
942 write_lock_irq(&sfp->rq_list_lock);
943 if (srp->done) {
944 srp->done = 2;
945 write_unlock_irq(&sfp->rq_list_lock);
946 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
947 return (result < 0) ? result : 0;
948 }
949 srp->orphan = 1;
950 write_unlock_irq(&sfp->rq_list_lock);
951 return result; /* -ERESTARTSYS because signal hit process */
952 case SG_SET_TIMEOUT:
953 result = get_user(val, ip);
954 if (result)
955 return result;
956 if (val < 0)
957 return -EIO;
958 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
959 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
960 INT_MAX);
961 sfp->timeout_user = val;
962 sfp->timeout = mult_frac(val, HZ, USER_HZ);
963
964 return 0;
965 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
966 /* strange ..., for backward compatibility */
967 return sfp->timeout_user;
968 case SG_SET_FORCE_LOW_DMA:
969 /*
970 * N.B. This ioctl never worked properly, but failed to
971 * return an error value. So returning '0' to keep compability
972 * with legacy applications.
973 */
974 return 0;
975 case SG_GET_LOW_DMA:
976 return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
977 case SG_GET_SCSI_ID:
978 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
979 return -EFAULT;
980 else {
981 sg_scsi_id_t __user *sg_idp = p;
982
983 if (atomic_read(&sdp->detaching))
984 return -ENODEV;
985 __put_user((int) sdp->device->host->host_no,
986 &sg_idp->host_no);
987 __put_user((int) sdp->device->channel,
988 &sg_idp->channel);
989 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
990 __put_user((int) sdp->device->lun, &sg_idp->lun);
991 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
992 __put_user((short) sdp->device->host->cmd_per_lun,
993 &sg_idp->h_cmd_per_lun);
994 __put_user((short) sdp->device->queue_depth,
995 &sg_idp->d_queue_depth);
996 __put_user(0, &sg_idp->unused[0]);
997 __put_user(0, &sg_idp->unused[1]);
998 return 0;
999 }
1000 case SG_SET_FORCE_PACK_ID:
1001 result = get_user(val, ip);
1002 if (result)
1003 return result;
1004 sfp->force_packid = val ? 1 : 0;
1005 return 0;
1006 case SG_GET_PACK_ID:
1007 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
1008 return -EFAULT;
1009 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1010 list_for_each_entry(srp, &sfp->rq_list, entry) {
1011 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1012 read_unlock_irqrestore(&sfp->rq_list_lock,
1013 iflags);
1014 __put_user(srp->header.pack_id, ip);
1015 return 0;
1016 }
1017 }
1018 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1019 __put_user(-1, ip);
1020 return 0;
1021 case SG_GET_NUM_WAITING:
1022 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1023 val = 0;
1024 list_for_each_entry(srp, &sfp->rq_list, entry) {
1025 if ((1 == srp->done) && (!srp->sg_io_owned))
1026 ++val;
1027 }
1028 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1029 return put_user(val, ip);
1030 case SG_GET_SG_TABLESIZE:
1031 return put_user(sdp->sg_tablesize, ip);
1032 case SG_SET_RESERVED_SIZE:
1033 result = get_user(val, ip);
1034 if (result)
1035 return result;
1036 if (val < 0)
1037 return -EINVAL;
1038 val = min_t(int, val,
1039 max_sectors_bytes(sdp->device->request_queue));
1040 mutex_lock(&sfp->f_mutex);
1041 if (val != sfp->reserve.bufflen) {
1042 if (sfp->mmap_called ||
1043 sfp->res_in_use) {
1044 mutex_unlock(&sfp->f_mutex);
1045 return -EBUSY;
1046 }
1047
1048 sg_remove_scat(sfp, &sfp->reserve);
1049 sg_build_reserve(sfp, val);
1050 }
1051 mutex_unlock(&sfp->f_mutex);
1052 return 0;
1053 case SG_GET_RESERVED_SIZE:
1054 val = min_t(int, sfp->reserve.bufflen,
1055 max_sectors_bytes(sdp->device->request_queue));
1056 return put_user(val, ip);
1057 case SG_SET_COMMAND_Q:
1058 result = get_user(val, ip);
1059 if (result)
1060 return result;
1061 sfp->cmd_q = val ? 1 : 0;
1062 return 0;
1063 case SG_GET_COMMAND_Q:
1064 return put_user((int) sfp->cmd_q, ip);
1065 case SG_SET_KEEP_ORPHAN:
1066 result = get_user(val, ip);
1067 if (result)
1068 return result;
1069 sfp->keep_orphan = val;
1070 return 0;
1071 case SG_GET_KEEP_ORPHAN:
1072 return put_user((int) sfp->keep_orphan, ip);
1073 case SG_NEXT_CMD_LEN:
1074 result = get_user(val, ip);
1075 if (result)
1076 return result;
1077 if (val > SG_MAX_CDB_SIZE)
1078 return -ENOMEM;
1079 sfp->next_cmd_len = (val > 0) ? val : 0;
1080 return 0;
1081 case SG_GET_VERSION_NUM:
1082 return put_user(sg_version_num, ip);
1083 case SG_GET_ACCESS_COUNT:
1084 /* faked - we don't have a real access count anymore */
1085 val = (sdp->device ? 1 : 0);
1086 return put_user(val, ip);
1087 case SG_GET_REQUEST_TABLE:
1088 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
1089 return -EFAULT;
1090 else {
1091 sg_req_info_t *rinfo;
1092
1093 rinfo = kzalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
1094 GFP_KERNEL);
1095 if (!rinfo)
1096 return -ENOMEM;
1097 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1098 sg_fill_request_table(sfp, rinfo);
1099 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1100 result = __copy_to_user(p, rinfo,
1101 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1102 result = result ? -EFAULT : 0;
1103 kfree(rinfo);
1104 return result;
1105 }
1106 case SG_EMULATED_HOST:
1107 if (atomic_read(&sdp->detaching))
1108 return -ENODEV;
1109 return put_user(sdp->device->host->hostt->emulated, ip);
1110 case SCSI_IOCTL_SEND_COMMAND:
1111 if (atomic_read(&sdp->detaching))
1112 return -ENODEV;
1113 if (read_only) {
1114 unsigned char opcode = WRITE_6;
1115 Scsi_Ioctl_Command __user *siocp = p;
1116
1117 if (copy_from_user(&opcode, siocp->data, 1))
1118 return -EFAULT;
1119 if (sg_allow_access(filp, &opcode))
1120 return -EPERM;
1121 }
1122 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1123 case SG_SET_DEBUG:
1124 result = get_user(val, ip);
1125 if (result)
1126 return result;
1127 sdp->sgdebug = (char) val;
1128 return 0;
1129 case BLKSECTGET:
1130 return put_user(max_sectors_bytes(sdp->device->request_queue),
1131 ip);
1132 case BLKTRACESETUP:
1133 return blk_trace_setup(sdp->device->request_queue,
1134 sdp->disk->disk_name,
1135 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1136 NULL,
1137 (char *)arg);
1138 case BLKTRACESTART:
1139 return blk_trace_startstop(sdp->device->request_queue, 1);
1140 case BLKTRACESTOP:
1141 return blk_trace_startstop(sdp->device->request_queue, 0);
1142 case BLKTRACETEARDOWN:
1143 return blk_trace_remove(sdp->device->request_queue);
1144 case SCSI_IOCTL_GET_IDLUN:
1145 case SCSI_IOCTL_GET_BUS_NUMBER:
1146 case SCSI_IOCTL_PROBE_HOST:
1147 case SG_GET_TRANSFORM:
1148 case SG_SCSI_RESET:
1149 if (atomic_read(&sdp->detaching))
1150 return -ENODEV;
1151 break;
1152 default:
1153 if (read_only)
1154 return -EPERM; /* don't know so take safe approach */
1155 break;
1156 }
1157
1158 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1159 cmd_in, filp->f_flags & O_NDELAY);
1160 if (result)
1161 return result;
1162 return scsi_ioctl(sdp->device, cmd_in, p);
1163 }
1164
1165 #ifdef CONFIG_COMPAT
1166 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1167 {
1168 Sg_device *sdp;
1169 Sg_fd *sfp;
1170 struct scsi_device *sdev;
1171
1172 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1173 return -ENXIO;
1174
1175 sdev = sdp->device;
1176 if (sdev->host->hostt->compat_ioctl) {
1177 int ret;
1178
1179 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1180
1181 return ret;
1182 }
1183
1184 return -ENOIOCTLCMD;
1185 }
1186 #endif
1187
1188 static unsigned int
1189 sg_poll(struct file *filp, poll_table * wait)
1190 {
1191 unsigned int res = 0;
1192 Sg_device *sdp;
1193 Sg_fd *sfp;
1194 Sg_request *srp;
1195 int count = 0;
1196 unsigned long iflags;
1197
1198 sfp = filp->private_data;
1199 if (!sfp)
1200 return POLLERR;
1201 sdp = sfp->parentdp;
1202 if (!sdp)
1203 return POLLERR;
1204 poll_wait(filp, &sfp->read_wait, wait);
1205 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1206 list_for_each_entry(srp, &sfp->rq_list, entry) {
1207 /* if any read waiting, flag it */
1208 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1209 res = POLLIN | POLLRDNORM;
1210 ++count;
1211 }
1212 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1213
1214 if (atomic_read(&sdp->detaching))
1215 res |= POLLHUP;
1216 else if (!sfp->cmd_q) {
1217 if (0 == count)
1218 res |= POLLOUT | POLLWRNORM;
1219 } else if (count < SG_MAX_QUEUE)
1220 res |= POLLOUT | POLLWRNORM;
1221 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1222 "sg_poll: res=0x%x\n", (int) res));
1223 return res;
1224 }
1225
1226 static int
1227 sg_fasync(int fd, struct file *filp, int mode)
1228 {
1229 Sg_device *sdp;
1230 Sg_fd *sfp;
1231
1232 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1233 return -ENXIO;
1234 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1235 "sg_fasync: mode=%d\n", mode));
1236
1237 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1238 }
1239
1240 static int
1241 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1242 {
1243 Sg_fd *sfp;
1244 unsigned long offset, len, sa;
1245 Sg_scatter_hold *rsv_schp;
1246 int k, length;
1247
1248 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1249 return VM_FAULT_SIGBUS;
1250 rsv_schp = &sfp->reserve;
1251 offset = vmf->pgoff << PAGE_SHIFT;
1252 if (offset >= rsv_schp->bufflen)
1253 return VM_FAULT_SIGBUS;
1254 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1255 "sg_vma_fault: offset=%lu, scatg=%d\n",
1256 offset, rsv_schp->k_use_sg));
1257 sa = vma->vm_start;
1258 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1259 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1260 len = vma->vm_end - sa;
1261 len = (len < length) ? len : length;
1262 if (offset < len) {
1263 struct page *page = nth_page(rsv_schp->pages[k],
1264 offset >> PAGE_SHIFT);
1265 get_page(page); /* increment page count */
1266 vmf->page = page;
1267 return 0; /* success */
1268 }
1269 sa += len;
1270 offset -= len;
1271 }
1272
1273 return VM_FAULT_SIGBUS;
1274 }
1275
1276 static const struct vm_operations_struct sg_mmap_vm_ops = {
1277 .fault = sg_vma_fault,
1278 };
1279
1280 static int
1281 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1282 {
1283 Sg_fd *sfp;
1284 unsigned long req_sz, len, sa;
1285 Sg_scatter_hold *rsv_schp;
1286 int k, length;
1287 int ret = 0;
1288
1289 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1290 return -ENXIO;
1291 req_sz = vma->vm_end - vma->vm_start;
1292 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1293 "sg_mmap starting, vm_start=%p, len=%d\n",
1294 (void *) vma->vm_start, (int) req_sz));
1295 if (vma->vm_pgoff)
1296 return -EINVAL; /* want no offset */
1297 rsv_schp = &sfp->reserve;
1298 mutex_lock(&sfp->f_mutex);
1299 if (req_sz > rsv_schp->bufflen) {
1300 ret = -ENOMEM; /* cannot map more than reserved buffer */
1301 goto out;
1302 }
1303
1304 sa = vma->vm_start;
1305 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1306 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1307 len = vma->vm_end - sa;
1308 len = (len < length) ? len : length;
1309 sa += len;
1310 }
1311
1312 sfp->mmap_called = 1;
1313 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1314 vma->vm_private_data = sfp;
1315 vma->vm_ops = &sg_mmap_vm_ops;
1316 out:
1317 mutex_unlock(&sfp->f_mutex);
1318 return ret;
1319 }
1320
1321 static void
1322 sg_rq_end_io_usercontext(struct work_struct *work)
1323 {
1324 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1325 struct sg_fd *sfp = srp->parentfp;
1326
1327 sg_finish_rem_req(srp);
1328 sg_remove_request(sfp, srp);
1329 kref_put(&sfp->f_ref, sg_remove_sfp);
1330 }
1331
1332 /*
1333 * This function is a "bottom half" handler that is called by the mid
1334 * level when a command is completed (or has failed).
1335 */
1336 static void
1337 sg_rq_end_io(struct request *rq, int uptodate)
1338 {
1339 struct sg_request *srp = rq->end_io_data;
1340 Sg_device *sdp;
1341 Sg_fd *sfp;
1342 unsigned long iflags;
1343 unsigned int ms;
1344 char *sense;
1345 int result, resid, done = 1;
1346
1347 if (WARN_ON(srp->done != 0))
1348 return;
1349
1350 sfp = srp->parentfp;
1351 if (WARN_ON(sfp == NULL))
1352 return;
1353
1354 sdp = sfp->parentdp;
1355 if (unlikely(atomic_read(&sdp->detaching)))
1356 pr_info("%s: device detaching\n", __func__);
1357
1358 sense = rq->sense;
1359 result = rq->errors;
1360 resid = rq->resid_len;
1361
1362 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1363 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1364 srp->header.pack_id, result));
1365 srp->header.resid = resid;
1366 ms = jiffies_to_msecs(jiffies);
1367 srp->header.duration = (ms > srp->header.duration) ?
1368 (ms - srp->header.duration) : 0;
1369 if (0 != result) {
1370 struct scsi_sense_hdr sshdr;
1371
1372 srp->header.status = 0xff & result;
1373 srp->header.masked_status = status_byte(result);
1374 srp->header.msg_status = msg_byte(result);
1375 srp->header.host_status = host_byte(result);
1376 srp->header.driver_status = driver_byte(result);
1377 if ((sdp->sgdebug > 0) &&
1378 ((CHECK_CONDITION == srp->header.masked_status) ||
1379 (COMMAND_TERMINATED == srp->header.masked_status)))
1380 __scsi_print_sense(sdp->device, __func__, sense,
1381 SCSI_SENSE_BUFFERSIZE);
1382
1383 /* Following if statement is a patch supplied by Eric Youngdale */
1384 if (driver_byte(result) != 0
1385 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1386 && !scsi_sense_is_deferred(&sshdr)
1387 && sshdr.sense_key == UNIT_ATTENTION
1388 && sdp->device->removable) {
1389 /* Detected possible disc change. Set the bit - this */
1390 /* may be used if there are filesystems using this device */
1391 sdp->device->changed = 1;
1392 }
1393 }
1394 /* Rely on write phase to clean out srp status values, so no "else" */
1395
1396 /*
1397 * Free the request as soon as it is complete so that its resources
1398 * can be reused without waiting for userspace to read() the
1399 * result. But keep the associated bio (if any) around until
1400 * blk_rq_unmap_user() can be called from user context.
1401 */
1402 srp->rq = NULL;
1403 if (rq->cmd != rq->__cmd)
1404 kfree(rq->cmd);
1405 __blk_put_request(rq->q, rq);
1406
1407 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1408 if (unlikely(srp->orphan)) {
1409 if (sfp->keep_orphan)
1410 srp->sg_io_owned = 0;
1411 else
1412 done = 0;
1413 }
1414 srp->done = done;
1415 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1416
1417 if (likely(done)) {
1418 /* Now wake up any sg_read() that is waiting for this
1419 * packet.
1420 */
1421 wake_up_interruptible(&sfp->read_wait);
1422 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1423 kref_put(&sfp->f_ref, sg_remove_sfp);
1424 } else {
1425 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1426 schedule_work(&srp->ew.work);
1427 }
1428 }
1429
1430 static const struct file_operations sg_fops = {
1431 .owner = THIS_MODULE,
1432 .read = sg_read,
1433 .write = sg_write,
1434 .poll = sg_poll,
1435 .unlocked_ioctl = sg_ioctl,
1436 #ifdef CONFIG_COMPAT
1437 .compat_ioctl = sg_compat_ioctl,
1438 #endif
1439 .open = sg_open,
1440 .mmap = sg_mmap,
1441 .release = sg_release,
1442 .fasync = sg_fasync,
1443 .llseek = no_llseek,
1444 };
1445
1446 static struct class *sg_sysfs_class;
1447
1448 static int sg_sysfs_valid = 0;
1449
1450 static Sg_device *
1451 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1452 {
1453 struct request_queue *q = scsidp->request_queue;
1454 Sg_device *sdp;
1455 unsigned long iflags;
1456 int error;
1457 u32 k;
1458
1459 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1460 if (!sdp) {
1461 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1462 "failure\n", __func__);
1463 return ERR_PTR(-ENOMEM);
1464 }
1465
1466 idr_preload(GFP_KERNEL);
1467 write_lock_irqsave(&sg_index_lock, iflags);
1468
1469 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1470 if (error < 0) {
1471 if (error == -ENOSPC) {
1472 sdev_printk(KERN_WARNING, scsidp,
1473 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1474 scsidp->type, SG_MAX_DEVS - 1);
1475 error = -ENODEV;
1476 } else {
1477 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1478 "allocation Sg_device failure: %d\n",
1479 __func__, error);
1480 }
1481 goto out_unlock;
1482 }
1483 k = error;
1484
1485 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1486 "sg_alloc: dev=%d \n", k));
1487 sprintf(disk->disk_name, "sg%d", k);
1488 disk->first_minor = k;
1489 sdp->disk = disk;
1490 sdp->device = scsidp;
1491 mutex_init(&sdp->open_rel_lock);
1492 INIT_LIST_HEAD(&sdp->sfds);
1493 init_waitqueue_head(&sdp->open_wait);
1494 atomic_set(&sdp->detaching, 0);
1495 rwlock_init(&sdp->sfd_lock);
1496 sdp->sg_tablesize = queue_max_segments(q);
1497 sdp->index = k;
1498 kref_init(&sdp->d_ref);
1499 error = 0;
1500
1501 out_unlock:
1502 write_unlock_irqrestore(&sg_index_lock, iflags);
1503 idr_preload_end();
1504
1505 if (error) {
1506 kfree(sdp);
1507 return ERR_PTR(error);
1508 }
1509 return sdp;
1510 }
1511
1512 static int
1513 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1514 {
1515 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1516 struct gendisk *disk;
1517 Sg_device *sdp = NULL;
1518 struct cdev * cdev = NULL;
1519 int error;
1520 unsigned long iflags;
1521
1522 disk = alloc_disk(1);
1523 if (!disk) {
1524 pr_warn("%s: alloc_disk failed\n", __func__);
1525 return -ENOMEM;
1526 }
1527 disk->major = SCSI_GENERIC_MAJOR;
1528
1529 error = -ENOMEM;
1530 cdev = cdev_alloc();
1531 if (!cdev) {
1532 pr_warn("%s: cdev_alloc failed\n", __func__);
1533 goto out;
1534 }
1535 cdev->owner = THIS_MODULE;
1536 cdev->ops = &sg_fops;
1537
1538 sdp = sg_alloc(disk, scsidp);
1539 if (IS_ERR(sdp)) {
1540 pr_warn("%s: sg_alloc failed\n", __func__);
1541 error = PTR_ERR(sdp);
1542 goto out;
1543 }
1544
1545 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1546 if (error)
1547 goto cdev_add_err;
1548
1549 sdp->cdev = cdev;
1550 if (sg_sysfs_valid) {
1551 struct device *sg_class_member;
1552
1553 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1554 MKDEV(SCSI_GENERIC_MAJOR,
1555 sdp->index),
1556 sdp, "%s", disk->disk_name);
1557 if (IS_ERR(sg_class_member)) {
1558 pr_err("%s: device_create failed\n", __func__);
1559 error = PTR_ERR(sg_class_member);
1560 goto cdev_add_err;
1561 }
1562 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1563 &sg_class_member->kobj, "generic");
1564 if (error)
1565 pr_err("%s: unable to make symlink 'generic' back "
1566 "to sg%d\n", __func__, sdp->index);
1567 } else
1568 pr_warn("%s: sg_sys Invalid\n", __func__);
1569
1570 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1571 "type %d\n", sdp->index, scsidp->type);
1572
1573 dev_set_drvdata(cl_dev, sdp);
1574
1575 return 0;
1576
1577 cdev_add_err:
1578 write_lock_irqsave(&sg_index_lock, iflags);
1579 idr_remove(&sg_index_idr, sdp->index);
1580 write_unlock_irqrestore(&sg_index_lock, iflags);
1581 kfree(sdp);
1582
1583 out:
1584 put_disk(disk);
1585 if (cdev)
1586 cdev_del(cdev);
1587 return error;
1588 }
1589
1590 static void
1591 sg_device_destroy(struct kref *kref)
1592 {
1593 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1594 unsigned long flags;
1595
1596 /* CAUTION! Note that the device can still be found via idr_find()
1597 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1598 * any other cleanup.
1599 */
1600
1601 write_lock_irqsave(&sg_index_lock, flags);
1602 idr_remove(&sg_index_idr, sdp->index);
1603 write_unlock_irqrestore(&sg_index_lock, flags);
1604
1605 SCSI_LOG_TIMEOUT(3,
1606 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1607
1608 put_disk(sdp->disk);
1609 kfree(sdp);
1610 }
1611
1612 static void
1613 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1614 {
1615 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1616 Sg_device *sdp = dev_get_drvdata(cl_dev);
1617 unsigned long iflags;
1618 Sg_fd *sfp;
1619 int val;
1620
1621 if (!sdp)
1622 return;
1623 /* want sdp->detaching non-zero as soon as possible */
1624 val = atomic_inc_return(&sdp->detaching);
1625 if (val > 1)
1626 return; /* only want to do following once per device */
1627
1628 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1629 "%s\n", __func__));
1630
1631 read_lock_irqsave(&sdp->sfd_lock, iflags);
1632 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1633 wake_up_interruptible_all(&sfp->read_wait);
1634 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1635 }
1636 wake_up_interruptible_all(&sdp->open_wait);
1637 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1638
1639 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1640 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1641 cdev_del(sdp->cdev);
1642 sdp->cdev = NULL;
1643
1644 kref_put(&sdp->d_ref, sg_device_destroy);
1645 }
1646
1647 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1648 module_param_named(def_reserved_size, def_reserved_size, int,
1649 S_IRUGO | S_IWUSR);
1650 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1651
1652 MODULE_AUTHOR("Douglas Gilbert");
1653 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1654 MODULE_LICENSE("GPL");
1655 MODULE_VERSION(SG_VERSION_STR);
1656 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1657
1658 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1659 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1660 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1661 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1662
1663 static int __init
1664 init_sg(void)
1665 {
1666 int rc;
1667
1668 if (scatter_elem_sz < PAGE_SIZE) {
1669 scatter_elem_sz = PAGE_SIZE;
1670 scatter_elem_sz_prev = scatter_elem_sz;
1671 }
1672 if (def_reserved_size >= 0)
1673 sg_big_buff = def_reserved_size;
1674 else
1675 def_reserved_size = sg_big_buff;
1676
1677 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1678 SG_MAX_DEVS, "sg");
1679 if (rc)
1680 return rc;
1681 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1682 if ( IS_ERR(sg_sysfs_class) ) {
1683 rc = PTR_ERR(sg_sysfs_class);
1684 goto err_out;
1685 }
1686 sg_sysfs_valid = 1;
1687 rc = scsi_register_interface(&sg_interface);
1688 if (0 == rc) {
1689 #ifdef CONFIG_SCSI_PROC_FS
1690 sg_proc_init();
1691 #endif /* CONFIG_SCSI_PROC_FS */
1692 return 0;
1693 }
1694 class_destroy(sg_sysfs_class);
1695 err_out:
1696 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1697 return rc;
1698 }
1699
1700 static void __exit
1701 exit_sg(void)
1702 {
1703 #ifdef CONFIG_SCSI_PROC_FS
1704 sg_proc_cleanup();
1705 #endif /* CONFIG_SCSI_PROC_FS */
1706 scsi_unregister_interface(&sg_interface);
1707 class_destroy(sg_sysfs_class);
1708 sg_sysfs_valid = 0;
1709 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1710 SG_MAX_DEVS);
1711 idr_destroy(&sg_index_idr);
1712 }
1713
1714 static int
1715 sg_start_req(Sg_request *srp, unsigned char *cmd)
1716 {
1717 int res;
1718 struct request *rq;
1719 Sg_fd *sfp = srp->parentfp;
1720 sg_io_hdr_t *hp = &srp->header;
1721 int dxfer_len = (int) hp->dxfer_len;
1722 int dxfer_dir = hp->dxfer_direction;
1723 unsigned int iov_count = hp->iovec_count;
1724 Sg_scatter_hold *req_schp = &srp->data;
1725 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1726 struct request_queue *q = sfp->parentdp->device->request_queue;
1727 struct rq_map_data *md, map_data;
1728 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1729 unsigned char *long_cmdp = NULL;
1730
1731 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1732 "sg_start_req: dxfer_len=%d\n",
1733 dxfer_len));
1734
1735 if (hp->cmd_len > BLK_MAX_CDB) {
1736 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1737 if (!long_cmdp)
1738 return -ENOMEM;
1739 }
1740
1741 /*
1742 * NOTE
1743 *
1744 * With scsi-mq enabled, there are a fixed number of preallocated
1745 * requests equal in number to shost->can_queue. If all of the
1746 * preallocated requests are already in use, then using GFP_ATOMIC with
1747 * blk_get_request() will return -EWOULDBLOCK, whereas using GFP_KERNEL
1748 * will cause blk_get_request() to sleep until an active command
1749 * completes, freeing up a request. Neither option is ideal, but
1750 * GFP_KERNEL is the better choice to prevent userspace from getting an
1751 * unexpected EWOULDBLOCK.
1752 *
1753 * With scsi-mq disabled, blk_get_request() with GFP_KERNEL usually
1754 * does not sleep except under memory pressure.
1755 */
1756 rq = blk_get_request(q, rw, GFP_KERNEL);
1757 if (IS_ERR(rq)) {
1758 kfree(long_cmdp);
1759 return PTR_ERR(rq);
1760 }
1761
1762 blk_rq_set_block_pc(rq);
1763
1764 if (hp->cmd_len > BLK_MAX_CDB)
1765 rq->cmd = long_cmdp;
1766 memcpy(rq->cmd, cmd, hp->cmd_len);
1767 rq->cmd_len = hp->cmd_len;
1768
1769 srp->rq = rq;
1770 rq->end_io_data = srp;
1771 rq->sense = srp->sense_b;
1772 rq->retries = SG_DEFAULT_RETRIES;
1773
1774 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1775 return 0;
1776
1777 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1778 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1779 !sfp->parentdp->device->host->unchecked_isa_dma &&
1780 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1781 md = NULL;
1782 else
1783 md = &map_data;
1784
1785 if (md) {
1786 mutex_lock(&sfp->f_mutex);
1787 if (dxfer_len <= rsv_schp->bufflen &&
1788 !sfp->res_in_use) {
1789 sfp->res_in_use = 1;
1790 sg_link_reserve(sfp, srp, dxfer_len);
1791 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1792 res = -EBUSY; /* sfp->res_in_use == 1 */
1793 if (dxfer_len > rsv_schp->bufflen)
1794 res = -ENOMEM;
1795 mutex_unlock(&sfp->f_mutex);
1796 return res;
1797 } else {
1798 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1799 if (res) {
1800 mutex_unlock(&sfp->f_mutex);
1801 return res;
1802 }
1803 }
1804 mutex_unlock(&sfp->f_mutex);
1805
1806 md->pages = req_schp->pages;
1807 md->page_order = req_schp->page_order;
1808 md->nr_entries = req_schp->k_use_sg;
1809 md->offset = 0;
1810 md->null_mapped = hp->dxferp ? 0 : 1;
1811 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1812 md->from_user = 1;
1813 else
1814 md->from_user = 0;
1815 }
1816
1817 if (iov_count) {
1818 struct iovec *iov = NULL;
1819 struct iov_iter i;
1820
1821 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1822 if (res < 0)
1823 return res;
1824
1825 iov_iter_truncate(&i, hp->dxfer_len);
1826 if (!iov_iter_count(&i)) {
1827 kfree(iov);
1828 return -EINVAL;
1829 }
1830
1831 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1832 kfree(iov);
1833 } else
1834 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1835 hp->dxfer_len, GFP_ATOMIC);
1836
1837 if (!res) {
1838 srp->bio = rq->bio;
1839
1840 if (!md) {
1841 req_schp->dio_in_use = 1;
1842 hp->info |= SG_INFO_DIRECT_IO;
1843 }
1844 }
1845 return res;
1846 }
1847
1848 static int
1849 sg_finish_rem_req(Sg_request *srp)
1850 {
1851 int ret = 0;
1852
1853 Sg_fd *sfp = srp->parentfp;
1854 Sg_scatter_hold *req_schp = &srp->data;
1855
1856 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1857 "sg_finish_rem_req: res_used=%d\n",
1858 (int) srp->res_used));
1859 if (srp->bio)
1860 ret = blk_rq_unmap_user(srp->bio);
1861
1862 if (srp->rq) {
1863 if (srp->rq->cmd != srp->rq->__cmd)
1864 kfree(srp->rq->cmd);
1865 blk_put_request(srp->rq);
1866 }
1867
1868 if (srp->res_used)
1869 sg_unlink_reserve(sfp, srp);
1870 else
1871 sg_remove_scat(sfp, req_schp);
1872
1873 return ret;
1874 }
1875
1876 static int
1877 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1878 {
1879 int sg_bufflen = tablesize * sizeof(struct page *);
1880 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1881
1882 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1883 if (!schp->pages)
1884 return -ENOMEM;
1885 schp->sglist_len = sg_bufflen;
1886 return tablesize; /* number of scat_gath elements allocated */
1887 }
1888
1889 static int
1890 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1891 {
1892 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1893 int sg_tablesize = sfp->parentdp->sg_tablesize;
1894 int blk_size = buff_size, order;
1895 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1896 struct sg_device *sdp = sfp->parentdp;
1897
1898 if (blk_size < 0)
1899 return -EFAULT;
1900 if (0 == blk_size)
1901 ++blk_size; /* don't know why */
1902 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1903 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1904 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1905 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1906 buff_size, blk_size));
1907
1908 /* N.B. ret_sz carried into this block ... */
1909 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1910 if (mx_sc_elems < 0)
1911 return mx_sc_elems; /* most likely -ENOMEM */
1912
1913 num = scatter_elem_sz;
1914 if (unlikely(num != scatter_elem_sz_prev)) {
1915 if (num < PAGE_SIZE) {
1916 scatter_elem_sz = PAGE_SIZE;
1917 scatter_elem_sz_prev = PAGE_SIZE;
1918 } else
1919 scatter_elem_sz_prev = num;
1920 }
1921
1922 if (sdp->device->host->unchecked_isa_dma)
1923 gfp_mask |= GFP_DMA;
1924
1925 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1926 gfp_mask |= __GFP_ZERO;
1927
1928 order = get_order(num);
1929 retry:
1930 ret_sz = 1 << (PAGE_SHIFT + order);
1931
1932 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1933 k++, rem_sz -= ret_sz) {
1934
1935 num = (rem_sz > scatter_elem_sz_prev) ?
1936 scatter_elem_sz_prev : rem_sz;
1937
1938 schp->pages[k] = alloc_pages(gfp_mask | __GFP_ZERO, order);
1939 if (!schp->pages[k])
1940 goto out;
1941
1942 if (num == scatter_elem_sz_prev) {
1943 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1944 scatter_elem_sz = ret_sz;
1945 scatter_elem_sz_prev = ret_sz;
1946 }
1947 }
1948
1949 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1950 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1951 k, num, ret_sz));
1952 } /* end of for loop */
1953
1954 schp->page_order = order;
1955 schp->k_use_sg = k;
1956 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1957 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1958 k, rem_sz));
1959
1960 schp->bufflen = blk_size;
1961 if (rem_sz > 0) /* must have failed */
1962 return -ENOMEM;
1963 return 0;
1964 out:
1965 for (i = 0; i < k; i++)
1966 __free_pages(schp->pages[i], order);
1967
1968 if (--order >= 0)
1969 goto retry;
1970
1971 return -ENOMEM;
1972 }
1973
1974 static void
1975 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1976 {
1977 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1978 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1979 if (schp->pages && schp->sglist_len > 0) {
1980 if (!schp->dio_in_use) {
1981 int k;
1982
1983 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1984 SCSI_LOG_TIMEOUT(5,
1985 sg_printk(KERN_INFO, sfp->parentdp,
1986 "sg_remove_scat: k=%d, pg=0x%p\n",
1987 k, schp->pages[k]));
1988 __free_pages(schp->pages[k], schp->page_order);
1989 }
1990
1991 kfree(schp->pages);
1992 }
1993 }
1994 memset(schp, 0, sizeof (*schp));
1995 }
1996
1997 static int
1998 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1999 {
2000 Sg_scatter_hold *schp = &srp->data;
2001 int k, num;
2002
2003 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2004 "sg_read_oxfer: num_read_xfer=%d\n",
2005 num_read_xfer));
2006 if ((!outp) || (num_read_xfer <= 0))
2007 return 0;
2008
2009 num = 1 << (PAGE_SHIFT + schp->page_order);
2010 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
2011 if (num > num_read_xfer) {
2012 if (__copy_to_user(outp, page_address(schp->pages[k]),
2013 num_read_xfer))
2014 return -EFAULT;
2015 break;
2016 } else {
2017 if (__copy_to_user(outp, page_address(schp->pages[k]),
2018 num))
2019 return -EFAULT;
2020 num_read_xfer -= num;
2021 if (num_read_xfer <= 0)
2022 break;
2023 outp += num;
2024 }
2025 }
2026
2027 return 0;
2028 }
2029
2030 static void
2031 sg_build_reserve(Sg_fd * sfp, int req_size)
2032 {
2033 Sg_scatter_hold *schp = &sfp->reserve;
2034
2035 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2036 "sg_build_reserve: req_size=%d\n", req_size));
2037 do {
2038 if (req_size < PAGE_SIZE)
2039 req_size = PAGE_SIZE;
2040 if (0 == sg_build_indirect(schp, sfp, req_size))
2041 return;
2042 else
2043 sg_remove_scat(sfp, schp);
2044 req_size >>= 1; /* divide by 2 */
2045 } while (req_size > (PAGE_SIZE / 2));
2046 }
2047
2048 static void
2049 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2050 {
2051 Sg_scatter_hold *req_schp = &srp->data;
2052 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2053 int k, num, rem;
2054
2055 srp->res_used = 1;
2056 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2057 "sg_link_reserve: size=%d\n", size));
2058 rem = size;
2059
2060 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2061 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2062 if (rem <= num) {
2063 req_schp->k_use_sg = k + 1;
2064 req_schp->sglist_len = rsv_schp->sglist_len;
2065 req_schp->pages = rsv_schp->pages;
2066
2067 req_schp->bufflen = size;
2068 req_schp->page_order = rsv_schp->page_order;
2069 break;
2070 } else
2071 rem -= num;
2072 }
2073
2074 if (k >= rsv_schp->k_use_sg)
2075 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2076 "sg_link_reserve: BAD size\n"));
2077 }
2078
2079 static void
2080 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2081 {
2082 Sg_scatter_hold *req_schp = &srp->data;
2083
2084 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2085 "sg_unlink_reserve: req->k_use_sg=%d\n",
2086 (int) req_schp->k_use_sg));
2087 req_schp->k_use_sg = 0;
2088 req_schp->bufflen = 0;
2089 req_schp->pages = NULL;
2090 req_schp->page_order = 0;
2091 req_schp->sglist_len = 0;
2092 srp->res_used = 0;
2093 /* Called without mutex lock to avoid deadlock */
2094 sfp->res_in_use = 0;
2095 }
2096
2097 static Sg_request *
2098 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2099 {
2100 Sg_request *resp;
2101 unsigned long iflags;
2102
2103 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2104 list_for_each_entry(resp, &sfp->rq_list, entry) {
2105 /* look for requests that are ready + not SG_IO owned */
2106 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2107 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2108 resp->done = 2; /* guard against other readers */
2109 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2110 return resp;
2111 }
2112 }
2113 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2114 return NULL;
2115 }
2116
2117 /* always adds to end of list */
2118 static Sg_request *
2119 sg_add_request(Sg_fd * sfp)
2120 {
2121 int k;
2122 unsigned long iflags;
2123 Sg_request *rp = sfp->req_arr;
2124
2125 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2126 if (!list_empty(&sfp->rq_list)) {
2127 if (!sfp->cmd_q)
2128 goto out_unlock;
2129
2130 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2131 if (!rp->parentfp)
2132 break;
2133 }
2134 if (k >= SG_MAX_QUEUE)
2135 goto out_unlock;
2136 }
2137 memset(rp, 0, sizeof (Sg_request));
2138 rp->parentfp = sfp;
2139 rp->header.duration = jiffies_to_msecs(jiffies);
2140 list_add_tail(&rp->entry, &sfp->rq_list);
2141 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2142 return rp;
2143 out_unlock:
2144 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2145 return NULL;
2146 }
2147
2148 /* Return of 1 for found; 0 for not found */
2149 static int
2150 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2151 {
2152 unsigned long iflags;
2153 int res = 0;
2154
2155 if (!sfp || !srp || list_empty(&sfp->rq_list))
2156 return res;
2157 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2158 if (!list_empty(&srp->entry)) {
2159 list_del(&srp->entry);
2160 srp->parentfp = NULL;
2161 res = 1;
2162 }
2163 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2164 return res;
2165 }
2166
2167 static Sg_fd *
2168 sg_add_sfp(Sg_device * sdp)
2169 {
2170 Sg_fd *sfp;
2171 unsigned long iflags;
2172 int bufflen;
2173
2174 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2175 if (!sfp)
2176 return ERR_PTR(-ENOMEM);
2177
2178 init_waitqueue_head(&sfp->read_wait);
2179 rwlock_init(&sfp->rq_list_lock);
2180 INIT_LIST_HEAD(&sfp->rq_list);
2181 kref_init(&sfp->f_ref);
2182 mutex_init(&sfp->f_mutex);
2183 sfp->timeout = SG_DEFAULT_TIMEOUT;
2184 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2185 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2186 sfp->cmd_q = SG_DEF_COMMAND_Q;
2187 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2188 sfp->parentdp = sdp;
2189 write_lock_irqsave(&sdp->sfd_lock, iflags);
2190 if (atomic_read(&sdp->detaching)) {
2191 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2192 kfree(sfp);
2193 return ERR_PTR(-ENODEV);
2194 }
2195 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2196 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2197 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2198 "sg_add_sfp: sfp=0x%p\n", sfp));
2199 if (unlikely(sg_big_buff != def_reserved_size))
2200 sg_big_buff = def_reserved_size;
2201
2202 bufflen = min_t(int, sg_big_buff,
2203 max_sectors_bytes(sdp->device->request_queue));
2204 sg_build_reserve(sfp, bufflen);
2205 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2206 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2207 sfp->reserve.bufflen,
2208 sfp->reserve.k_use_sg));
2209
2210 kref_get(&sdp->d_ref);
2211 __module_get(THIS_MODULE);
2212 return sfp;
2213 }
2214
2215 static void
2216 sg_remove_sfp_usercontext(struct work_struct *work)
2217 {
2218 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2219 struct sg_device *sdp = sfp->parentdp;
2220 Sg_request *srp;
2221 unsigned long iflags;
2222
2223 /* Cleanup any responses which were never read(). */
2224 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2225 while (!list_empty(&sfp->rq_list)) {
2226 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2227 sg_finish_rem_req(srp);
2228 list_del(&srp->entry);
2229 srp->parentfp = NULL;
2230 }
2231 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2232
2233 if (sfp->reserve.bufflen > 0) {
2234 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2235 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2236 (int) sfp->reserve.bufflen,
2237 (int) sfp->reserve.k_use_sg));
2238 sg_remove_scat(sfp, &sfp->reserve);
2239 }
2240
2241 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2242 "sg_remove_sfp: sfp=0x%p\n", sfp));
2243 kfree(sfp);
2244
2245 scsi_device_put(sdp->device);
2246 kref_put(&sdp->d_ref, sg_device_destroy);
2247 module_put(THIS_MODULE);
2248 }
2249
2250 static void
2251 sg_remove_sfp(struct kref *kref)
2252 {
2253 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2254 struct sg_device *sdp = sfp->parentdp;
2255 unsigned long iflags;
2256
2257 write_lock_irqsave(&sdp->sfd_lock, iflags);
2258 list_del(&sfp->sfd_siblings);
2259 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2260
2261 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2262 schedule_work(&sfp->ew.work);
2263 }
2264
2265 #ifdef CONFIG_SCSI_PROC_FS
2266 static int
2267 sg_idr_max_id(int id, void *p, void *data)
2268 {
2269 int *k = data;
2270
2271 if (*k < id)
2272 *k = id;
2273
2274 return 0;
2275 }
2276
2277 static int
2278 sg_last_dev(void)
2279 {
2280 int k = -1;
2281 unsigned long iflags;
2282
2283 read_lock_irqsave(&sg_index_lock, iflags);
2284 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2285 read_unlock_irqrestore(&sg_index_lock, iflags);
2286 return k + 1; /* origin 1 */
2287 }
2288 #endif
2289
2290 /* must be called with sg_index_lock held */
2291 static Sg_device *sg_lookup_dev(int dev)
2292 {
2293 return idr_find(&sg_index_idr, dev);
2294 }
2295
2296 static Sg_device *
2297 sg_get_dev(int dev)
2298 {
2299 struct sg_device *sdp;
2300 unsigned long flags;
2301
2302 read_lock_irqsave(&sg_index_lock, flags);
2303 sdp = sg_lookup_dev(dev);
2304 if (!sdp)
2305 sdp = ERR_PTR(-ENXIO);
2306 else if (atomic_read(&sdp->detaching)) {
2307 /* If sdp->detaching, then the refcount may already be 0, in
2308 * which case it would be a bug to do kref_get().
2309 */
2310 sdp = ERR_PTR(-ENODEV);
2311 } else
2312 kref_get(&sdp->d_ref);
2313 read_unlock_irqrestore(&sg_index_lock, flags);
2314
2315 return sdp;
2316 }
2317
2318 #ifdef CONFIG_SCSI_PROC_FS
2319
2320 static struct proc_dir_entry *sg_proc_sgp = NULL;
2321
2322 static char sg_proc_sg_dirname[] = "scsi/sg";
2323
2324 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2325
2326 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2327 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2328 size_t count, loff_t *off);
2329 static const struct file_operations adio_fops = {
2330 .owner = THIS_MODULE,
2331 .open = sg_proc_single_open_adio,
2332 .read = seq_read,
2333 .llseek = seq_lseek,
2334 .write = sg_proc_write_adio,
2335 .release = single_release,
2336 };
2337
2338 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2339 static ssize_t sg_proc_write_dressz(struct file *filp,
2340 const char __user *buffer, size_t count, loff_t *off);
2341 static const struct file_operations dressz_fops = {
2342 .owner = THIS_MODULE,
2343 .open = sg_proc_single_open_dressz,
2344 .read = seq_read,
2345 .llseek = seq_lseek,
2346 .write = sg_proc_write_dressz,
2347 .release = single_release,
2348 };
2349
2350 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2351 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2352 static const struct file_operations version_fops = {
2353 .owner = THIS_MODULE,
2354 .open = sg_proc_single_open_version,
2355 .read = seq_read,
2356 .llseek = seq_lseek,
2357 .release = single_release,
2358 };
2359
2360 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2361 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2362 static const struct file_operations devhdr_fops = {
2363 .owner = THIS_MODULE,
2364 .open = sg_proc_single_open_devhdr,
2365 .read = seq_read,
2366 .llseek = seq_lseek,
2367 .release = single_release,
2368 };
2369
2370 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2371 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2372 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2373 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2374 static void dev_seq_stop(struct seq_file *s, void *v);
2375 static const struct file_operations dev_fops = {
2376 .owner = THIS_MODULE,
2377 .open = sg_proc_open_dev,
2378 .read = seq_read,
2379 .llseek = seq_lseek,
2380 .release = seq_release,
2381 };
2382 static const struct seq_operations dev_seq_ops = {
2383 .start = dev_seq_start,
2384 .next = dev_seq_next,
2385 .stop = dev_seq_stop,
2386 .show = sg_proc_seq_show_dev,
2387 };
2388
2389 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2390 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2391 static const struct file_operations devstrs_fops = {
2392 .owner = THIS_MODULE,
2393 .open = sg_proc_open_devstrs,
2394 .read = seq_read,
2395 .llseek = seq_lseek,
2396 .release = seq_release,
2397 };
2398 static const struct seq_operations devstrs_seq_ops = {
2399 .start = dev_seq_start,
2400 .next = dev_seq_next,
2401 .stop = dev_seq_stop,
2402 .show = sg_proc_seq_show_devstrs,
2403 };
2404
2405 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2406 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2407 static const struct file_operations debug_fops = {
2408 .owner = THIS_MODULE,
2409 .open = sg_proc_open_debug,
2410 .read = seq_read,
2411 .llseek = seq_lseek,
2412 .release = seq_release,
2413 };
2414 static const struct seq_operations debug_seq_ops = {
2415 .start = dev_seq_start,
2416 .next = dev_seq_next,
2417 .stop = dev_seq_stop,
2418 .show = sg_proc_seq_show_debug,
2419 };
2420
2421
2422 struct sg_proc_leaf {
2423 const char * name;
2424 const struct file_operations * fops;
2425 };
2426
2427 static const struct sg_proc_leaf sg_proc_leaf_arr[] = {
2428 {"allow_dio", &adio_fops},
2429 {"debug", &debug_fops},
2430 {"def_reserved_size", &dressz_fops},
2431 {"device_hdr", &devhdr_fops},
2432 {"devices", &dev_fops},
2433 {"device_strs", &devstrs_fops},
2434 {"version", &version_fops}
2435 };
2436
2437 static int
2438 sg_proc_init(void)
2439 {
2440 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2441 int k;
2442
2443 sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2444 if (!sg_proc_sgp)
2445 return 1;
2446 for (k = 0; k < num_leaves; ++k) {
2447 const struct sg_proc_leaf *leaf = &sg_proc_leaf_arr[k];
2448 umode_t mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2449 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2450 }
2451 return 0;
2452 }
2453
2454 static void
2455 sg_proc_cleanup(void)
2456 {
2457 int k;
2458 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2459
2460 if (!sg_proc_sgp)
2461 return;
2462 for (k = 0; k < num_leaves; ++k)
2463 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2464 remove_proc_entry(sg_proc_sg_dirname, NULL);
2465 }
2466
2467
2468 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2469 {
2470 seq_printf(s, "%d\n", *((int *)s->private));
2471 return 0;
2472 }
2473
2474 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2475 {
2476 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2477 }
2478
2479 static ssize_t
2480 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2481 size_t count, loff_t *off)
2482 {
2483 int err;
2484 unsigned long num;
2485
2486 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2487 return -EACCES;
2488 err = kstrtoul_from_user(buffer, count, 0, &num);
2489 if (err)
2490 return err;
2491 sg_allow_dio = num ? 1 : 0;
2492 return count;
2493 }
2494
2495 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2496 {
2497 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2498 }
2499
2500 static ssize_t
2501 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2502 size_t count, loff_t *off)
2503 {
2504 int err;
2505 unsigned long k = ULONG_MAX;
2506
2507 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2508 return -EACCES;
2509
2510 err = kstrtoul_from_user(buffer, count, 0, &k);
2511 if (err)
2512 return err;
2513 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2514 sg_big_buff = k;
2515 return count;
2516 }
2517 return -ERANGE;
2518 }
2519
2520 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2521 {
2522 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2523 sg_version_date);
2524 return 0;
2525 }
2526
2527 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2528 {
2529 return single_open(file, sg_proc_seq_show_version, NULL);
2530 }
2531
2532 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2533 {
2534 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2535 return 0;
2536 }
2537
2538 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2539 {
2540 return single_open(file, sg_proc_seq_show_devhdr, NULL);
2541 }
2542
2543 struct sg_proc_deviter {
2544 loff_t index;
2545 size_t max;
2546 };
2547
2548 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2549 {
2550 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2551
2552 s->private = it;
2553 if (! it)
2554 return NULL;
2555
2556 it->index = *pos;
2557 it->max = sg_last_dev();
2558 if (it->index >= it->max)
2559 return NULL;
2560 return it;
2561 }
2562
2563 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2564 {
2565 struct sg_proc_deviter * it = s->private;
2566
2567 *pos = ++it->index;
2568 return (it->index < it->max) ? it : NULL;
2569 }
2570
2571 static void dev_seq_stop(struct seq_file *s, void *v)
2572 {
2573 kfree(s->private);
2574 }
2575
2576 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2577 {
2578 return seq_open(file, &dev_seq_ops);
2579 }
2580
2581 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2582 {
2583 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2584 Sg_device *sdp;
2585 struct scsi_device *scsidp;
2586 unsigned long iflags;
2587
2588 read_lock_irqsave(&sg_index_lock, iflags);
2589 sdp = it ? sg_lookup_dev(it->index) : NULL;
2590 if ((NULL == sdp) || (NULL == sdp->device) ||
2591 (atomic_read(&sdp->detaching)))
2592 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2593 else {
2594 scsidp = sdp->device;
2595 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2596 scsidp->host->host_no, scsidp->channel,
2597 scsidp->id, scsidp->lun, (int) scsidp->type,
2598 1,
2599 (int) scsidp->queue_depth,
2600 (int) atomic_read(&scsidp->device_busy),
2601 (int) scsi_device_online(scsidp));
2602 }
2603 read_unlock_irqrestore(&sg_index_lock, iflags);
2604 return 0;
2605 }
2606
2607 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2608 {
2609 return seq_open(file, &devstrs_seq_ops);
2610 }
2611
2612 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2613 {
2614 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2615 Sg_device *sdp;
2616 struct scsi_device *scsidp;
2617 unsigned long iflags;
2618
2619 read_lock_irqsave(&sg_index_lock, iflags);
2620 sdp = it ? sg_lookup_dev(it->index) : NULL;
2621 scsidp = sdp ? sdp->device : NULL;
2622 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2623 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2624 scsidp->vendor, scsidp->model, scsidp->rev);
2625 else
2626 seq_puts(s, "<no active device>\n");
2627 read_unlock_irqrestore(&sg_index_lock, iflags);
2628 return 0;
2629 }
2630
2631 /* must be called while holding sg_index_lock */
2632 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2633 {
2634 int k, new_interface, blen, usg;
2635 Sg_request *srp;
2636 Sg_fd *fp;
2637 const sg_io_hdr_t *hp;
2638 const char * cp;
2639 unsigned int ms;
2640
2641 k = 0;
2642 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2643 k++;
2644 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2645 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2646 "(res)sgat=%d low_dma=%d\n", k,
2647 jiffies_to_msecs(fp->timeout),
2648 fp->reserve.bufflen,
2649 (int) fp->reserve.k_use_sg,
2650 (int) sdp->device->host->unchecked_isa_dma);
2651 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2652 (int) fp->cmd_q, (int) fp->force_packid,
2653 (int) fp->keep_orphan);
2654 list_for_each_entry(srp, &fp->rq_list, entry) {
2655 hp = &srp->header;
2656 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2657 if (srp->res_used) {
2658 if (new_interface &&
2659 (SG_FLAG_MMAP_IO & hp->flags))
2660 cp = " mmap>> ";
2661 else
2662 cp = " rb>> ";
2663 } else {
2664 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2665 cp = " dio>> ";
2666 else
2667 cp = " ";
2668 }
2669 seq_puts(s, cp);
2670 blen = srp->data.bufflen;
2671 usg = srp->data.k_use_sg;
2672 seq_puts(s, srp->done ?
2673 ((1 == srp->done) ? "rcv:" : "fin:")
2674 : "act:");
2675 seq_printf(s, " id=%d blen=%d",
2676 srp->header.pack_id, blen);
2677 if (srp->done)
2678 seq_printf(s, " dur=%d", hp->duration);
2679 else {
2680 ms = jiffies_to_msecs(jiffies);
2681 seq_printf(s, " t_o/elap=%d/%d",
2682 (new_interface ? hp->timeout :
2683 jiffies_to_msecs(fp->timeout)),
2684 (ms > hp->duration ? ms - hp->duration : 0));
2685 }
2686 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2687 (int) srp->data.cmd_opcode);
2688 }
2689 if (list_empty(&fp->rq_list))
2690 seq_puts(s, " No requests active\n");
2691 read_unlock(&fp->rq_list_lock);
2692 }
2693 }
2694
2695 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2696 {
2697 return seq_open(file, &debug_seq_ops);
2698 }
2699
2700 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2701 {
2702 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2703 Sg_device *sdp;
2704 unsigned long iflags;
2705
2706 if (it && (0 == it->index))
2707 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2708 (int)it->max, sg_big_buff);
2709
2710 read_lock_irqsave(&sg_index_lock, iflags);
2711 sdp = it ? sg_lookup_dev(it->index) : NULL;
2712 if (NULL == sdp)
2713 goto skip;
2714 read_lock(&sdp->sfd_lock);
2715 if (!list_empty(&sdp->sfds)) {
2716 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2717 if (atomic_read(&sdp->detaching))
2718 seq_puts(s, "detaching pending close ");
2719 else if (sdp->device) {
2720 struct scsi_device *scsidp = sdp->device;
2721
2722 seq_printf(s, "%d:%d:%d:%llu em=%d",
2723 scsidp->host->host_no,
2724 scsidp->channel, scsidp->id,
2725 scsidp->lun,
2726 scsidp->host->hostt->emulated);
2727 }
2728 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2729 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2730 sg_proc_debug_helper(s, sdp);
2731 }
2732 read_unlock(&sdp->sfd_lock);
2733 skip:
2734 read_unlock_irqrestore(&sg_index_lock, iflags);
2735 return 0;
2736 }
2737
2738 #endif /* CONFIG_SCSI_PROC_FS */
2739
2740 module_init(init_sg);
2741 module_exit(exit_sg);
Linux with added FPC-III support