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1/*
2 * History:
3 * Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
4 * to allow user process control of SCSI devices.
5 * Development Sponsored by Killy Corp. NY NY
6 *
7 * Original driver (sg.c):
8 * Copyright (C) 1992 Lawrence Foard
9 * Version 2 and 3 extensions to driver:
10 * Copyright (C) 1998 - 2005 Douglas Gilbert
11 *
12 * Modified 19-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
17 * any later version.
18 *
19 */
20
21static int sg_version_num = 30534; /* 2 digits for each component */
22#define SG_VERSION_STR "3.5.34"
23
24/*
25 * D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
26 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
27 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING
28 * (otherwise the macros compile to empty statements).
29 *
30 */
31#include <linux/module.h>
32
33#include <linux/fs.h>
34#include <linux/kernel.h>
35#include <linux/sched.h>
36#include <linux/string.h>
37#include <linux/mm.h>
38#include <linux/aio.h>
39#include <linux/errno.h>
40#include <linux/mtio.h>
41#include <linux/ioctl.h>
42#include <linux/slab.h>
43#include <linux/fcntl.h>
44#include <linux/init.h>
45#include <linux/poll.h>
46#include <linux/moduleparam.h>
47#include <linux/cdev.h>
48#include <linux/idr.h>
49#include <linux/seq_file.h>
50#include <linux/blkdev.h>
51#include <linux/delay.h>
52#include <linux/blktrace_api.h>
53#include <linux/mutex.h>
54#include <linux/ratelimit.h>
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>
67static char *sg_version_date = "20061027";
68
69static int sg_proc_init(void);
70static void sg_proc_cleanup(void);
71#endif
72
73#define SG_ALLOW_DIO_DEF 0
74
75#define SG_MAX_DEVS 32768
76
77/*
78 * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
79 * Then when using 32 bit integers x * m may overflow during the calculation.
80 * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
81 * calculates the same, but prevents the overflow when both m and d
82 * are "small" numbers (like HZ and USER_HZ).
83 * Of course an overflow is inavoidable if the result of muldiv doesn't fit
84 * in 32 bits.
85 */
86#define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
87
88#define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
89
90int sg_big_buff = SG_DEF_RESERVED_SIZE;
91/* N.B. This variable is readable and writeable via
92 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
93 of this size (or less if there is not enough memory) will be reserved
94 for use by this file descriptor. [Deprecated usage: this variable is also
95 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
96 the kernel (i.e. it is not a module).] */
97static int def_reserved_size = -1; /* picks up init parameter */
98static int sg_allow_dio = SG_ALLOW_DIO_DEF;
99
100static int scatter_elem_sz = SG_SCATTER_SZ;
101static int scatter_elem_sz_prev = SG_SCATTER_SZ;
102
103#define SG_SECTOR_SZ 512
104
105static int sg_add(struct device *, struct class_interface *);
106static void sg_remove(struct device *, struct class_interface *);
107
108static DEFINE_SPINLOCK(sg_open_exclusive_lock);
109
110static DEFINE_IDR(sg_index_idr);
111static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
112 file descriptor list for device */
113
114static struct class_interface sg_interface = {
115 .add_dev = sg_add,
116 .remove_dev = sg_remove,
117};
118
119typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
120 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
121 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
122 unsigned bufflen; /* Size of (aggregate) data buffer */
123 struct page **pages;
124 int page_order;
125 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
126 unsigned char cmd_opcode; /* first byte of command */
127} Sg_scatter_hold;
128
129struct sg_device; /* forward declarations */
130struct sg_fd;
131
132typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
133 struct sg_request *nextrp; /* NULL -> tail request (slist) */
134 struct sg_fd *parentfp; /* NULL -> not in use */
135 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
136 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
137 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
138 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
139 char orphan; /* 1 -> drop on sight, 0 -> normal */
140 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
141 /* done protected by rq_list_lock */
142 char done; /* 0->before bh, 1->before read, 2->read */
143 struct request *rq;
144 struct bio *bio;
145 struct execute_work ew;
146} Sg_request;
147
148typedef struct sg_fd { /* holds the state of a file descriptor */
149 /* sfd_siblings is protected by sg_index_lock */
150 struct list_head sfd_siblings;
151 struct sg_device *parentdp; /* owning device */
152 wait_queue_head_t read_wait; /* queue read until command done */
153 rwlock_t rq_list_lock; /* protect access to list in req_arr */
154 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
155 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
156 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
157 unsigned save_scat_len; /* original length of trunc. scat. element */
158 Sg_request *headrp; /* head of request slist, NULL->empty */
159 struct fasync_struct *async_qp; /* used by asynchronous notification */
160 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
161 char low_dma; /* as in parent but possibly overridden to 1 */
162 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
163 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
164 char next_cmd_len; /* 0 -> automatic (def), >0 -> use on next write() */
165 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
166 char mmap_called; /* 0 -> mmap() never called on this fd */
167 struct kref f_ref;
168 struct execute_work ew;
169} Sg_fd;
170
171typedef struct sg_device { /* holds the state of each scsi generic device */
172 struct scsi_device *device;
173 wait_queue_head_t o_excl_wait; /* queue open() when O_EXCL in use */
174 int sg_tablesize; /* adapter's max scatter-gather table size */
175 u32 index; /* device index number */
176 /* sfds is protected by sg_index_lock */
177 struct list_head sfds;
178 volatile char detached; /* 0->attached, 1->detached pending removal */
179 /* exclude protected by sg_open_exclusive_lock */
180 char exclude; /* opened for exclusive access */
181 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
182 struct gendisk *disk;
183 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
184 struct kref d_ref;
185} Sg_device;
186
187/* tasklet or soft irq callback */
188static void sg_rq_end_io(struct request *rq, int uptodate);
189static int sg_start_req(Sg_request *srp, unsigned char *cmd);
190static int sg_finish_rem_req(Sg_request * srp);
191static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
192static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
193 Sg_request * srp);
194static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
195 const char __user *buf, size_t count, int blocking,
196 int read_only, int sg_io_owned, Sg_request **o_srp);
197static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
198 unsigned char *cmnd, int timeout, int blocking);
199static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
200static void sg_remove_scat(Sg_scatter_hold * schp);
201static void sg_build_reserve(Sg_fd * sfp, int req_size);
202static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
203static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
204static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
205static void sg_remove_sfp(struct kref *);
206static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
207static Sg_request *sg_add_request(Sg_fd * sfp);
208static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
209static int sg_res_in_use(Sg_fd * sfp);
210static Sg_device *sg_get_dev(int dev);
211static void sg_put_dev(Sg_device *sdp);
212
213#define SZ_SG_HEADER sizeof(struct sg_header)
214#define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
215#define SZ_SG_IOVEC sizeof(sg_iovec_t)
216#define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
217
218static int sg_allow_access(struct file *filp, unsigned char *cmd)
219{
220 struct sg_fd *sfp = filp->private_data;
221
222 if (sfp->parentdp->device->type == TYPE_SCANNER)
223 return 0;
224
225 return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
226}
227
228static int get_exclude(Sg_device *sdp)
229{
230 unsigned long flags;
231 int ret;
232
233 spin_lock_irqsave(&sg_open_exclusive_lock, flags);
234 ret = sdp->exclude;
235 spin_unlock_irqrestore(&sg_open_exclusive_lock, flags);
236 return ret;
237}
238
239static int set_exclude(Sg_device *sdp, char val)
240{
241 unsigned long flags;
242
243 spin_lock_irqsave(&sg_open_exclusive_lock, flags);
244 sdp->exclude = val;
245 spin_unlock_irqrestore(&sg_open_exclusive_lock, flags);
246 return val;
247}
248
249static int sfds_list_empty(Sg_device *sdp)
250{
251 unsigned long flags;
252 int ret;
253
254 read_lock_irqsave(&sg_index_lock, flags);
255 ret = list_empty(&sdp->sfds);
256 read_unlock_irqrestore(&sg_index_lock, flags);
257 return ret;
258}
259
260static int
261sg_open(struct inode *inode, struct file *filp)
262{
263 int dev = iminor(inode);
264 int flags = filp->f_flags;
265 struct request_queue *q;
266 Sg_device *sdp;
267 Sg_fd *sfp;
268 int res;
269 int retval;
270
271 nonseekable_open(inode, filp);
272 SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
273 sdp = sg_get_dev(dev);
274 if (IS_ERR(sdp)) {
275 retval = PTR_ERR(sdp);
276 sdp = NULL;
277 goto sg_put;
278 }
279
280 /* This driver's module count bumped by fops_get in <linux/fs.h> */
281 /* Prevent the device driver from vanishing while we sleep */
282 retval = scsi_device_get(sdp->device);
283 if (retval)
284 goto sg_put;
285
286 retval = scsi_autopm_get_device(sdp->device);
287 if (retval)
288 goto sdp_put;
289
290 if (!((flags & O_NONBLOCK) ||
291 scsi_block_when_processing_errors(sdp->device))) {
292 retval = -ENXIO;
293 /* we are in error recovery for this device */
294 goto error_out;
295 }
296
297 if (flags & O_EXCL) {
298 if (O_RDONLY == (flags & O_ACCMODE)) {
299 retval = -EPERM; /* Can't lock it with read only access */
300 goto error_out;
301 }
302 if (!sfds_list_empty(sdp) && (flags & O_NONBLOCK)) {
303 retval = -EBUSY;
304 goto error_out;
305 }
306 res = wait_event_interruptible(sdp->o_excl_wait,
307 ((!sfds_list_empty(sdp) || get_exclude(sdp)) ? 0 : set_exclude(sdp, 1)));
308 if (res) {
309 retval = res; /* -ERESTARTSYS because signal hit process */
310 goto error_out;
311 }
312 } else if (get_exclude(sdp)) { /* some other fd has an exclusive lock on dev */
313 if (flags & O_NONBLOCK) {
314 retval = -EBUSY;
315 goto error_out;
316 }
317 res = wait_event_interruptible(sdp->o_excl_wait, !get_exclude(sdp));
318 if (res) {
319 retval = res; /* -ERESTARTSYS because signal hit process */
320 goto error_out;
321 }
322 }
323 if (sdp->detached) {
324 retval = -ENODEV;
325 goto error_out;
326 }
327 if (sfds_list_empty(sdp)) { /* no existing opens on this device */
328 sdp->sgdebug = 0;
329 q = sdp->device->request_queue;
330 sdp->sg_tablesize = queue_max_segments(q);
331 }
332 if ((sfp = sg_add_sfp(sdp, dev)))
333 filp->private_data = sfp;
334 else {
335 if (flags & O_EXCL) {
336 set_exclude(sdp, 0); /* undo if error */
337 wake_up_interruptible(&sdp->o_excl_wait);
338 }
339 retval = -ENOMEM;
340 goto error_out;
341 }
342 retval = 0;
343error_out:
344 if (retval) {
345 scsi_autopm_put_device(sdp->device);
346sdp_put:
347 scsi_device_put(sdp->device);
348 }
349sg_put:
350 if (sdp)
351 sg_put_dev(sdp);
352 return retval;
353}
354
355/* Following function was formerly called 'sg_close' */
356static int
357sg_release(struct inode *inode, struct file *filp)
358{
359 Sg_device *sdp;
360 Sg_fd *sfp;
361
362 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
363 return -ENXIO;
364 SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
365
366 set_exclude(sdp, 0);
367 wake_up_interruptible(&sdp->o_excl_wait);
368
369 scsi_autopm_put_device(sdp->device);
370 kref_put(&sfp->f_ref, sg_remove_sfp);
371 return 0;
372}
373
374static ssize_t
375sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
376{
377 Sg_device *sdp;
378 Sg_fd *sfp;
379 Sg_request *srp;
380 int req_pack_id = -1;
381 sg_io_hdr_t *hp;
382 struct sg_header *old_hdr = NULL;
383 int retval = 0;
384
385 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
386 return -ENXIO;
387 SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
388 sdp->disk->disk_name, (int) count));
389
390 if (!access_ok(VERIFY_WRITE, buf, count))
391 return -EFAULT;
392 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
393 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
394 if (!old_hdr)
395 return -ENOMEM;
396 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
397 retval = -EFAULT;
398 goto free_old_hdr;
399 }
400 if (old_hdr->reply_len < 0) {
401 if (count >= SZ_SG_IO_HDR) {
402 sg_io_hdr_t *new_hdr;
403 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
404 if (!new_hdr) {
405 retval = -ENOMEM;
406 goto free_old_hdr;
407 }
408 retval =__copy_from_user
409 (new_hdr, buf, SZ_SG_IO_HDR);
410 req_pack_id = new_hdr->pack_id;
411 kfree(new_hdr);
412 if (retval) {
413 retval = -EFAULT;
414 goto free_old_hdr;
415 }
416 }
417 } else
418 req_pack_id = old_hdr->pack_id;
419 }
420 srp = sg_get_rq_mark(sfp, req_pack_id);
421 if (!srp) { /* now wait on packet to arrive */
422 if (sdp->detached) {
423 retval = -ENODEV;
424 goto free_old_hdr;
425 }
426 if (filp->f_flags & O_NONBLOCK) {
427 retval = -EAGAIN;
428 goto free_old_hdr;
429 }
430 retval = wait_event_interruptible(sfp->read_wait,
431 (sdp->detached ||
432 (srp = sg_get_rq_mark(sfp, req_pack_id))));
433 if (sdp->detached) {
434 retval = -ENODEV;
435 goto free_old_hdr;
436 }
437 if (retval) {
438 /* -ERESTARTSYS as signal hit process */
439 goto free_old_hdr;
440 }
441 }
442 if (srp->header.interface_id != '\0') {
443 retval = sg_new_read(sfp, buf, count, srp);
444 goto free_old_hdr;
445 }
446
447 hp = &srp->header;
448 if (old_hdr == NULL) {
449 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
450 if (! old_hdr) {
451 retval = -ENOMEM;
452 goto free_old_hdr;
453 }
454 }
455 memset(old_hdr, 0, SZ_SG_HEADER);
456 old_hdr->reply_len = (int) hp->timeout;
457 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
458 old_hdr->pack_id = hp->pack_id;
459 old_hdr->twelve_byte =
460 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
461 old_hdr->target_status = hp->masked_status;
462 old_hdr->host_status = hp->host_status;
463 old_hdr->driver_status = hp->driver_status;
464 if ((CHECK_CONDITION & hp->masked_status) ||
465 (DRIVER_SENSE & hp->driver_status))
466 memcpy(old_hdr->sense_buffer, srp->sense_b,
467 sizeof (old_hdr->sense_buffer));
468 switch (hp->host_status) {
469 /* This setup of 'result' is for backward compatibility and is best
470 ignored by the user who should use target, host + driver status */
471 case DID_OK:
472 case DID_PASSTHROUGH:
473 case DID_SOFT_ERROR:
474 old_hdr->result = 0;
475 break;
476 case DID_NO_CONNECT:
477 case DID_BUS_BUSY:
478 case DID_TIME_OUT:
479 old_hdr->result = EBUSY;
480 break;
481 case DID_BAD_TARGET:
482 case DID_ABORT:
483 case DID_PARITY:
484 case DID_RESET:
485 case DID_BAD_INTR:
486 old_hdr->result = EIO;
487 break;
488 case DID_ERROR:
489 old_hdr->result = (srp->sense_b[0] == 0 &&
490 hp->masked_status == GOOD) ? 0 : EIO;
491 break;
492 default:
493 old_hdr->result = EIO;
494 break;
495 }
496
497 /* Now copy the result back to the user buffer. */
498 if (count >= SZ_SG_HEADER) {
499 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
500 retval = -EFAULT;
501 goto free_old_hdr;
502 }
503 buf += SZ_SG_HEADER;
504 if (count > old_hdr->reply_len)
505 count = old_hdr->reply_len;
506 if (count > SZ_SG_HEADER) {
507 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
508 retval = -EFAULT;
509 goto free_old_hdr;
510 }
511 }
512 } else
513 count = (old_hdr->result == 0) ? 0 : -EIO;
514 sg_finish_rem_req(srp);
515 retval = count;
516free_old_hdr:
517 kfree(old_hdr);
518 return retval;
519}
520
521static ssize_t
522sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
523{
524 sg_io_hdr_t *hp = &srp->header;
525 int err = 0;
526 int len;
527
528 if (count < SZ_SG_IO_HDR) {
529 err = -EINVAL;
530 goto err_out;
531 }
532 hp->sb_len_wr = 0;
533 if ((hp->mx_sb_len > 0) && hp->sbp) {
534 if ((CHECK_CONDITION & hp->masked_status) ||
535 (DRIVER_SENSE & hp->driver_status)) {
536 int sb_len = SCSI_SENSE_BUFFERSIZE;
537 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
538 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
539 len = (len > sb_len) ? sb_len : len;
540 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
541 err = -EFAULT;
542 goto err_out;
543 }
544 hp->sb_len_wr = len;
545 }
546 }
547 if (hp->masked_status || hp->host_status || hp->driver_status)
548 hp->info |= SG_INFO_CHECK;
549 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
550 err = -EFAULT;
551 goto err_out;
552 }
553err_out:
554 err = sg_finish_rem_req(srp);
555 return (0 == err) ? count : err;
556}
557
558static ssize_t
559sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
560{
561 int mxsize, cmd_size, k;
562 int input_size, blocking;
563 unsigned char opcode;
564 Sg_device *sdp;
565 Sg_fd *sfp;
566 Sg_request *srp;
567 struct sg_header old_hdr;
568 sg_io_hdr_t *hp;
569 unsigned char cmnd[MAX_COMMAND_SIZE];
570
571 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
572 return -ENXIO;
573 SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
574 sdp->disk->disk_name, (int) count));
575 if (sdp->detached)
576 return -ENODEV;
577 if (!((filp->f_flags & O_NONBLOCK) ||
578 scsi_block_when_processing_errors(sdp->device)))
579 return -ENXIO;
580
581 if (!access_ok(VERIFY_READ, buf, count))
582 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
583 if (count < SZ_SG_HEADER)
584 return -EIO;
585 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
586 return -EFAULT;
587 blocking = !(filp->f_flags & O_NONBLOCK);
588 if (old_hdr.reply_len < 0)
589 return sg_new_write(sfp, filp, buf, count,
590 blocking, 0, 0, NULL);
591 if (count < (SZ_SG_HEADER + 6))
592 return -EIO; /* The minimum scsi command length is 6 bytes. */
593
594 if (!(srp = sg_add_request(sfp))) {
595 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
596 return -EDOM;
597 }
598 buf += SZ_SG_HEADER;
599 __get_user(opcode, buf);
600 if (sfp->next_cmd_len > 0) {
601 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
602 SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
603 sfp->next_cmd_len = 0;
604 sg_remove_request(sfp, srp);
605 return -EIO;
606 }
607 cmd_size = sfp->next_cmd_len;
608 sfp->next_cmd_len = 0; /* reset so only this write() effected */
609 } else {
610 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
611 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
612 cmd_size = 12;
613 }
614 SCSI_LOG_TIMEOUT(4, printk(
615 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
616/* Determine buffer size. */
617 input_size = count - cmd_size;
618 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
619 mxsize -= SZ_SG_HEADER;
620 input_size -= SZ_SG_HEADER;
621 if (input_size < 0) {
622 sg_remove_request(sfp, srp);
623 return -EIO; /* User did not pass enough bytes for this command. */
624 }
625 hp = &srp->header;
626 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
627 hp->cmd_len = (unsigned char) cmd_size;
628 hp->iovec_count = 0;
629 hp->mx_sb_len = 0;
630 if (input_size > 0)
631 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
632 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
633 else
634 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
635 hp->dxfer_len = mxsize;
636 if (hp->dxfer_direction == SG_DXFER_TO_DEV)
637 hp->dxferp = (char __user *)buf + cmd_size;
638 else
639 hp->dxferp = NULL;
640 hp->sbp = NULL;
641 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
642 hp->flags = input_size; /* structure abuse ... */
643 hp->pack_id = old_hdr.pack_id;
644 hp->usr_ptr = NULL;
645 if (__copy_from_user(cmnd, buf, cmd_size))
646 return -EFAULT;
647 /*
648 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
649 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
650 * is a non-zero input_size, so emit a warning.
651 */
652 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
653 static char cmd[TASK_COMM_LEN];
654 if (strcmp(current->comm, cmd)) {
655 printk_ratelimited(KERN_WARNING
656 "sg_write: data in/out %d/%d bytes "
657 "for SCSI command 0x%x-- guessing "
658 "data in;\n program %s not setting "
659 "count and/or reply_len properly\n",
660 old_hdr.reply_len - (int)SZ_SG_HEADER,
661 input_size, (unsigned int) cmnd[0],
662 current->comm);
663 strcpy(cmd, current->comm);
664 }
665 }
666 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
667 return (k < 0) ? k : count;
668}
669
670static ssize_t
671sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
672 size_t count, int blocking, int read_only, int sg_io_owned,
673 Sg_request **o_srp)
674{
675 int k;
676 Sg_request *srp;
677 sg_io_hdr_t *hp;
678 unsigned char cmnd[MAX_COMMAND_SIZE];
679 int timeout;
680 unsigned long ul_timeout;
681
682 if (count < SZ_SG_IO_HDR)
683 return -EINVAL;
684 if (!access_ok(VERIFY_READ, buf, count))
685 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
686
687 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
688 if (!(srp = sg_add_request(sfp))) {
689 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
690 return -EDOM;
691 }
692 srp->sg_io_owned = sg_io_owned;
693 hp = &srp->header;
694 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
695 sg_remove_request(sfp, srp);
696 return -EFAULT;
697 }
698 if (hp->interface_id != 'S') {
699 sg_remove_request(sfp, srp);
700 return -ENOSYS;
701 }
702 if (hp->flags & SG_FLAG_MMAP_IO) {
703 if (hp->dxfer_len > sfp->reserve.bufflen) {
704 sg_remove_request(sfp, srp);
705 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
706 }
707 if (hp->flags & SG_FLAG_DIRECT_IO) {
708 sg_remove_request(sfp, srp);
709 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
710 }
711 if (sg_res_in_use(sfp)) {
712 sg_remove_request(sfp, srp);
713 return -EBUSY; /* reserve buffer already being used */
714 }
715 }
716 ul_timeout = msecs_to_jiffies(srp->header.timeout);
717 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
718 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
719 sg_remove_request(sfp, srp);
720 return -EMSGSIZE;
721 }
722 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
723 sg_remove_request(sfp, srp);
724 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
725 }
726 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
727 sg_remove_request(sfp, srp);
728 return -EFAULT;
729 }
730 if (read_only && sg_allow_access(file, cmnd)) {
731 sg_remove_request(sfp, srp);
732 return -EPERM;
733 }
734 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
735 if (k < 0)
736 return k;
737 if (o_srp)
738 *o_srp = srp;
739 return count;
740}
741
742static int
743sg_common_write(Sg_fd * sfp, Sg_request * srp,
744 unsigned char *cmnd, int timeout, int blocking)
745{
746 int k, data_dir;
747 Sg_device *sdp = sfp->parentdp;
748 sg_io_hdr_t *hp = &srp->header;
749
750 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
751 hp->status = 0;
752 hp->masked_status = 0;
753 hp->msg_status = 0;
754 hp->info = 0;
755 hp->host_status = 0;
756 hp->driver_status = 0;
757 hp->resid = 0;
758 SCSI_LOG_TIMEOUT(4, printk("sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
759 (int) cmnd[0], (int) hp->cmd_len));
760
761 k = sg_start_req(srp, cmnd);
762 if (k) {
763 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
764 sg_finish_rem_req(srp);
765 return k; /* probably out of space --> ENOMEM */
766 }
767 if (sdp->detached) {
768 if (srp->bio)
769 blk_end_request_all(srp->rq, -EIO);
770 sg_finish_rem_req(srp);
771 return -ENODEV;
772 }
773
774 switch (hp->dxfer_direction) {
775 case SG_DXFER_TO_FROM_DEV:
776 case SG_DXFER_FROM_DEV:
777 data_dir = DMA_FROM_DEVICE;
778 break;
779 case SG_DXFER_TO_DEV:
780 data_dir = DMA_TO_DEVICE;
781 break;
782 case SG_DXFER_UNKNOWN:
783 data_dir = DMA_BIDIRECTIONAL;
784 break;
785 default:
786 data_dir = DMA_NONE;
787 break;
788 }
789 hp->duration = jiffies_to_msecs(jiffies);
790
791 srp->rq->timeout = timeout;
792 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
793 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
794 srp->rq, 1, sg_rq_end_io);
795 return 0;
796}
797
798static int srp_done(Sg_fd *sfp, Sg_request *srp)
799{
800 unsigned long flags;
801 int ret;
802
803 read_lock_irqsave(&sfp->rq_list_lock, flags);
804 ret = srp->done;
805 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
806 return ret;
807}
808
809static long
810sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
811{
812 void __user *p = (void __user *)arg;
813 int __user *ip = p;
814 int result, val, read_only;
815 Sg_device *sdp;
816 Sg_fd *sfp;
817 Sg_request *srp;
818 unsigned long iflags;
819
820 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
821 return -ENXIO;
822
823 SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
824 sdp->disk->disk_name, (int) cmd_in));
825 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
826
827 switch (cmd_in) {
828 case SG_IO:
829 if (sdp->detached)
830 return -ENODEV;
831 if (!scsi_block_when_processing_errors(sdp->device))
832 return -ENXIO;
833 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
834 return -EFAULT;
835 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
836 1, read_only, 1, &srp);
837 if (result < 0)
838 return result;
839 result = wait_event_interruptible(sfp->read_wait,
840 (srp_done(sfp, srp) || sdp->detached));
841 if (sdp->detached)
842 return -ENODEV;
843 write_lock_irq(&sfp->rq_list_lock);
844 if (srp->done) {
845 srp->done = 2;
846 write_unlock_irq(&sfp->rq_list_lock);
847 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
848 return (result < 0) ? result : 0;
849 }
850 srp->orphan = 1;
851 write_unlock_irq(&sfp->rq_list_lock);
852 return result; /* -ERESTARTSYS because signal hit process */
853 case SG_SET_TIMEOUT:
854 result = get_user(val, ip);
855 if (result)
856 return result;
857 if (val < 0)
858 return -EIO;
859 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
860 val = MULDIV (INT_MAX, USER_HZ, HZ);
861 sfp->timeout_user = val;
862 sfp->timeout = MULDIV (val, HZ, USER_HZ);
863
864 return 0;
865 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
866 /* strange ..., for backward compatibility */
867 return sfp->timeout_user;
868 case SG_SET_FORCE_LOW_DMA:
869 result = get_user(val, ip);
870 if (result)
871 return result;
872 if (val) {
873 sfp->low_dma = 1;
874 if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
875 val = (int) sfp->reserve.bufflen;
876 sg_remove_scat(&sfp->reserve);
877 sg_build_reserve(sfp, val);
878 }
879 } else {
880 if (sdp->detached)
881 return -ENODEV;
882 sfp->low_dma = sdp->device->host->unchecked_isa_dma;
883 }
884 return 0;
885 case SG_GET_LOW_DMA:
886 return put_user((int) sfp->low_dma, ip);
887 case SG_GET_SCSI_ID:
888 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
889 return -EFAULT;
890 else {
891 sg_scsi_id_t __user *sg_idp = p;
892
893 if (sdp->detached)
894 return -ENODEV;
895 __put_user((int) sdp->device->host->host_no,
896 &sg_idp->host_no);
897 __put_user((int) sdp->device->channel,
898 &sg_idp->channel);
899 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
900 __put_user((int) sdp->device->lun, &sg_idp->lun);
901 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
902 __put_user((short) sdp->device->host->cmd_per_lun,
903 &sg_idp->h_cmd_per_lun);
904 __put_user((short) sdp->device->queue_depth,
905 &sg_idp->d_queue_depth);
906 __put_user(0, &sg_idp->unused[0]);
907 __put_user(0, &sg_idp->unused[1]);
908 return 0;
909 }
910 case SG_SET_FORCE_PACK_ID:
911 result = get_user(val, ip);
912 if (result)
913 return result;
914 sfp->force_packid = val ? 1 : 0;
915 return 0;
916 case SG_GET_PACK_ID:
917 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
918 return -EFAULT;
919 read_lock_irqsave(&sfp->rq_list_lock, iflags);
920 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
921 if ((1 == srp->done) && (!srp->sg_io_owned)) {
922 read_unlock_irqrestore(&sfp->rq_list_lock,
923 iflags);
924 __put_user(srp->header.pack_id, ip);
925 return 0;
926 }
927 }
928 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
929 __put_user(-1, ip);
930 return 0;
931 case SG_GET_NUM_WAITING:
932 read_lock_irqsave(&sfp->rq_list_lock, iflags);
933 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
934 if ((1 == srp->done) && (!srp->sg_io_owned))
935 ++val;
936 }
937 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
938 return put_user(val, ip);
939 case SG_GET_SG_TABLESIZE:
940 return put_user(sdp->sg_tablesize, ip);
941 case SG_SET_RESERVED_SIZE:
942 result = get_user(val, ip);
943 if (result)
944 return result;
945 if (val < 0)
946 return -EINVAL;
947 val = min_t(int, val,
948 queue_max_sectors(sdp->device->request_queue) * 512);
949 if (val != sfp->reserve.bufflen) {
950 if (sg_res_in_use(sfp) || sfp->mmap_called)
951 return -EBUSY;
952 sg_remove_scat(&sfp->reserve);
953 sg_build_reserve(sfp, val);
954 }
955 return 0;
956 case SG_GET_RESERVED_SIZE:
957 val = min_t(int, sfp->reserve.bufflen,
958 queue_max_sectors(sdp->device->request_queue) * 512);
959 return put_user(val, ip);
960 case SG_SET_COMMAND_Q:
961 result = get_user(val, ip);
962 if (result)
963 return result;
964 sfp->cmd_q = val ? 1 : 0;
965 return 0;
966 case SG_GET_COMMAND_Q:
967 return put_user((int) sfp->cmd_q, ip);
968 case SG_SET_KEEP_ORPHAN:
969 result = get_user(val, ip);
970 if (result)
971 return result;
972 sfp->keep_orphan = val;
973 return 0;
974 case SG_GET_KEEP_ORPHAN:
975 return put_user((int) sfp->keep_orphan, ip);
976 case SG_NEXT_CMD_LEN:
977 result = get_user(val, ip);
978 if (result)
979 return result;
980 sfp->next_cmd_len = (val > 0) ? val : 0;
981 return 0;
982 case SG_GET_VERSION_NUM:
983 return put_user(sg_version_num, ip);
984 case SG_GET_ACCESS_COUNT:
985 /* faked - we don't have a real access count anymore */
986 val = (sdp->device ? 1 : 0);
987 return put_user(val, ip);
988 case SG_GET_REQUEST_TABLE:
989 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
990 return -EFAULT;
991 else {
992 sg_req_info_t *rinfo;
993 unsigned int ms;
994
995 rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
996 GFP_KERNEL);
997 if (!rinfo)
998 return -ENOMEM;
999 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1000 for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
1001 ++val, srp = srp ? srp->nextrp : srp) {
1002 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
1003 if (srp) {
1004 rinfo[val].req_state = srp->done + 1;
1005 rinfo[val].problem =
1006 srp->header.masked_status &
1007 srp->header.host_status &
1008 srp->header.driver_status;
1009 if (srp->done)
1010 rinfo[val].duration =
1011 srp->header.duration;
1012 else {
1013 ms = jiffies_to_msecs(jiffies);
1014 rinfo[val].duration =
1015 (ms > srp->header.duration) ?
1016 (ms - srp->header.duration) : 0;
1017 }
1018 rinfo[val].orphan = srp->orphan;
1019 rinfo[val].sg_io_owned =
1020 srp->sg_io_owned;
1021 rinfo[val].pack_id =
1022 srp->header.pack_id;
1023 rinfo[val].usr_ptr =
1024 srp->header.usr_ptr;
1025 }
1026 }
1027 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1028 result = __copy_to_user(p, rinfo,
1029 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1030 result = result ? -EFAULT : 0;
1031 kfree(rinfo);
1032 return result;
1033 }
1034 case SG_EMULATED_HOST:
1035 if (sdp->detached)
1036 return -ENODEV;
1037 return put_user(sdp->device->host->hostt->emulated, ip);
1038 case SG_SCSI_RESET:
1039 if (sdp->detached)
1040 return -ENODEV;
1041 if (filp->f_flags & O_NONBLOCK) {
1042 if (scsi_host_in_recovery(sdp->device->host))
1043 return -EBUSY;
1044 } else if (!scsi_block_when_processing_errors(sdp->device))
1045 return -EBUSY;
1046 result = get_user(val, ip);
1047 if (result)
1048 return result;
1049 if (SG_SCSI_RESET_NOTHING == val)
1050 return 0;
1051 switch (val) {
1052 case SG_SCSI_RESET_DEVICE:
1053 val = SCSI_TRY_RESET_DEVICE;
1054 break;
1055 case SG_SCSI_RESET_TARGET:
1056 val = SCSI_TRY_RESET_TARGET;
1057 break;
1058 case SG_SCSI_RESET_BUS:
1059 val = SCSI_TRY_RESET_BUS;
1060 break;
1061 case SG_SCSI_RESET_HOST:
1062 val = SCSI_TRY_RESET_HOST;
1063 break;
1064 default:
1065 return -EINVAL;
1066 }
1067 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1068 return -EACCES;
1069 return (scsi_reset_provider(sdp->device, val) ==
1070 SUCCESS) ? 0 : -EIO;
1071 case SCSI_IOCTL_SEND_COMMAND:
1072 if (sdp->detached)
1073 return -ENODEV;
1074 if (read_only) {
1075 unsigned char opcode = WRITE_6;
1076 Scsi_Ioctl_Command __user *siocp = p;
1077
1078 if (copy_from_user(&opcode, siocp->data, 1))
1079 return -EFAULT;
1080 if (sg_allow_access(filp, &opcode))
1081 return -EPERM;
1082 }
1083 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1084 case SG_SET_DEBUG:
1085 result = get_user(val, ip);
1086 if (result)
1087 return result;
1088 sdp->sgdebug = (char) val;
1089 return 0;
1090 case SCSI_IOCTL_GET_IDLUN:
1091 case SCSI_IOCTL_GET_BUS_NUMBER:
1092 case SCSI_IOCTL_PROBE_HOST:
1093 case SG_GET_TRANSFORM:
1094 if (sdp->detached)
1095 return -ENODEV;
1096 return scsi_ioctl(sdp->device, cmd_in, p);
1097 case BLKSECTGET:
1098 return put_user(queue_max_sectors(sdp->device->request_queue) * 512,
1099 ip);
1100 case BLKTRACESETUP:
1101 return blk_trace_setup(sdp->device->request_queue,
1102 sdp->disk->disk_name,
1103 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1104 NULL,
1105 (char *)arg);
1106 case BLKTRACESTART:
1107 return blk_trace_startstop(sdp->device->request_queue, 1);
1108 case BLKTRACESTOP:
1109 return blk_trace_startstop(sdp->device->request_queue, 0);
1110 case BLKTRACETEARDOWN:
1111 return blk_trace_remove(sdp->device->request_queue);
1112 default:
1113 if (read_only)
1114 return -EPERM; /* don't know so take safe approach */
1115 return scsi_ioctl(sdp->device, cmd_in, p);
1116 }
1117}
1118
1119#ifdef CONFIG_COMPAT
1120static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1121{
1122 Sg_device *sdp;
1123 Sg_fd *sfp;
1124 struct scsi_device *sdev;
1125
1126 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1127 return -ENXIO;
1128
1129 sdev = sdp->device;
1130 if (sdev->host->hostt->compat_ioctl) {
1131 int ret;
1132
1133 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1134
1135 return ret;
1136 }
1137
1138 return -ENOIOCTLCMD;
1139}
1140#endif
1141
1142static unsigned int
1143sg_poll(struct file *filp, poll_table * wait)
1144{
1145 unsigned int res = 0;
1146 Sg_device *sdp;
1147 Sg_fd *sfp;
1148 Sg_request *srp;
1149 int count = 0;
1150 unsigned long iflags;
1151
1152 sfp = filp->private_data;
1153 if (!sfp)
1154 return POLLERR;
1155 sdp = sfp->parentdp;
1156 if (!sdp)
1157 return POLLERR;
1158 poll_wait(filp, &sfp->read_wait, wait);
1159 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1160 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1161 /* if any read waiting, flag it */
1162 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1163 res = POLLIN | POLLRDNORM;
1164 ++count;
1165 }
1166 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1167
1168 if (sdp->detached)
1169 res |= POLLHUP;
1170 else if (!sfp->cmd_q) {
1171 if (0 == count)
1172 res |= POLLOUT | POLLWRNORM;
1173 } else if (count < SG_MAX_QUEUE)
1174 res |= POLLOUT | POLLWRNORM;
1175 SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1176 sdp->disk->disk_name, (int) res));
1177 return res;
1178}
1179
1180static int
1181sg_fasync(int fd, struct file *filp, int mode)
1182{
1183 Sg_device *sdp;
1184 Sg_fd *sfp;
1185
1186 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1187 return -ENXIO;
1188 SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1189 sdp->disk->disk_name, mode));
1190
1191 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1192}
1193
1194static int
1195sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1196{
1197 Sg_fd *sfp;
1198 unsigned long offset, len, sa;
1199 Sg_scatter_hold *rsv_schp;
1200 int k, length;
1201
1202 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1203 return VM_FAULT_SIGBUS;
1204 rsv_schp = &sfp->reserve;
1205 offset = vmf->pgoff << PAGE_SHIFT;
1206 if (offset >= rsv_schp->bufflen)
1207 return VM_FAULT_SIGBUS;
1208 SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1209 offset, rsv_schp->k_use_sg));
1210 sa = vma->vm_start;
1211 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1212 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1213 len = vma->vm_end - sa;
1214 len = (len < length) ? len : length;
1215 if (offset < len) {
1216 struct page *page = nth_page(rsv_schp->pages[k],
1217 offset >> PAGE_SHIFT);
1218 get_page(page); /* increment page count */
1219 vmf->page = page;
1220 return 0; /* success */
1221 }
1222 sa += len;
1223 offset -= len;
1224 }
1225
1226 return VM_FAULT_SIGBUS;
1227}
1228
1229static const struct vm_operations_struct sg_mmap_vm_ops = {
1230 .fault = sg_vma_fault,
1231};
1232
1233static int
1234sg_mmap(struct file *filp, struct vm_area_struct *vma)
1235{
1236 Sg_fd *sfp;
1237 unsigned long req_sz, len, sa;
1238 Sg_scatter_hold *rsv_schp;
1239 int k, length;
1240
1241 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1242 return -ENXIO;
1243 req_sz = vma->vm_end - vma->vm_start;
1244 SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1245 (void *) vma->vm_start, (int) req_sz));
1246 if (vma->vm_pgoff)
1247 return -EINVAL; /* want no offset */
1248 rsv_schp = &sfp->reserve;
1249 if (req_sz > rsv_schp->bufflen)
1250 return -ENOMEM; /* cannot map more than reserved buffer */
1251
1252 sa = vma->vm_start;
1253 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1254 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1255 len = vma->vm_end - sa;
1256 len = (len < length) ? len : length;
1257 sa += len;
1258 }
1259
1260 sfp->mmap_called = 1;
1261 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
1262 vma->vm_private_data = sfp;
1263 vma->vm_ops = &sg_mmap_vm_ops;
1264 return 0;
1265}
1266
1267static void sg_rq_end_io_usercontext(struct work_struct *work)
1268{
1269 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1270 struct sg_fd *sfp = srp->parentfp;
1271
1272 sg_finish_rem_req(srp);
1273 kref_put(&sfp->f_ref, sg_remove_sfp);
1274}
1275
1276/*
1277 * This function is a "bottom half" handler that is called by the mid
1278 * level when a command is completed (or has failed).
1279 */
1280static void sg_rq_end_io(struct request *rq, int uptodate)
1281{
1282 struct sg_request *srp = rq->end_io_data;
1283 Sg_device *sdp;
1284 Sg_fd *sfp;
1285 unsigned long iflags;
1286 unsigned int ms;
1287 char *sense;
1288 int result, resid, done = 1;
1289
1290 if (WARN_ON(srp->done != 0))
1291 return;
1292
1293 sfp = srp->parentfp;
1294 if (WARN_ON(sfp == NULL))
1295 return;
1296
1297 sdp = sfp->parentdp;
1298 if (unlikely(sdp->detached))
1299 printk(KERN_INFO "sg_rq_end_io: device detached\n");
1300
1301 sense = rq->sense;
1302 result = rq->errors;
1303 resid = rq->resid_len;
1304
1305 SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1306 sdp->disk->disk_name, srp->header.pack_id, result));
1307 srp->header.resid = resid;
1308 ms = jiffies_to_msecs(jiffies);
1309 srp->header.duration = (ms > srp->header.duration) ?
1310 (ms - srp->header.duration) : 0;
1311 if (0 != result) {
1312 struct scsi_sense_hdr sshdr;
1313
1314 srp->header.status = 0xff & result;
1315 srp->header.masked_status = status_byte(result);
1316 srp->header.msg_status = msg_byte(result);
1317 srp->header.host_status = host_byte(result);
1318 srp->header.driver_status = driver_byte(result);
1319 if ((sdp->sgdebug > 0) &&
1320 ((CHECK_CONDITION == srp->header.masked_status) ||
1321 (COMMAND_TERMINATED == srp->header.masked_status)))
1322 __scsi_print_sense("sg_cmd_done", sense,
1323 SCSI_SENSE_BUFFERSIZE);
1324
1325 /* Following if statement is a patch supplied by Eric Youngdale */
1326 if (driver_byte(result) != 0
1327 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1328 && !scsi_sense_is_deferred(&sshdr)
1329 && sshdr.sense_key == UNIT_ATTENTION
1330 && sdp->device->removable) {
1331 /* Detected possible disc change. Set the bit - this */
1332 /* may be used if there are filesystems using this device */
1333 sdp->device->changed = 1;
1334 }
1335 }
1336 /* Rely on write phase to clean out srp status values, so no "else" */
1337
1338 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1339 if (unlikely(srp->orphan)) {
1340 if (sfp->keep_orphan)
1341 srp->sg_io_owned = 0;
1342 else
1343 done = 0;
1344 }
1345 srp->done = done;
1346 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1347
1348 if (likely(done)) {
1349 /* Now wake up any sg_read() that is waiting for this
1350 * packet.
1351 */
1352 wake_up_interruptible(&sfp->read_wait);
1353 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1354 kref_put(&sfp->f_ref, sg_remove_sfp);
1355 } else {
1356 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1357 schedule_work(&srp->ew.work);
1358 }
1359}
1360
1361static const struct file_operations sg_fops = {
1362 .owner = THIS_MODULE,
1363 .read = sg_read,
1364 .write = sg_write,
1365 .poll = sg_poll,
1366 .unlocked_ioctl = sg_ioctl,
1367#ifdef CONFIG_COMPAT
1368 .compat_ioctl = sg_compat_ioctl,
1369#endif
1370 .open = sg_open,
1371 .mmap = sg_mmap,
1372 .release = sg_release,
1373 .fasync = sg_fasync,
1374 .llseek = no_llseek,
1375};
1376
1377static struct class *sg_sysfs_class;
1378
1379static int sg_sysfs_valid = 0;
1380
1381static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1382{
1383 struct request_queue *q = scsidp->request_queue;
1384 Sg_device *sdp;
1385 unsigned long iflags;
1386 int error;
1387 u32 k;
1388
1389 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1390 if (!sdp) {
1391 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1392 return ERR_PTR(-ENOMEM);
1393 }
1394
1395 idr_preload(GFP_KERNEL);
1396 write_lock_irqsave(&sg_index_lock, iflags);
1397
1398 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1399 if (error < 0) {
1400 if (error == -ENOSPC) {
1401 sdev_printk(KERN_WARNING, scsidp,
1402 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1403 scsidp->type, SG_MAX_DEVS - 1);
1404 error = -ENODEV;
1405 } else {
1406 printk(KERN_WARNING
1407 "idr allocation Sg_device failure: %d\n", error);
1408 }
1409 goto out_unlock;
1410 }
1411 k = error;
1412
1413 SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1414 sprintf(disk->disk_name, "sg%d", k);
1415 disk->first_minor = k;
1416 sdp->disk = disk;
1417 sdp->device = scsidp;
1418 INIT_LIST_HEAD(&sdp->sfds);
1419 init_waitqueue_head(&sdp->o_excl_wait);
1420 sdp->sg_tablesize = queue_max_segments(q);
1421 sdp->index = k;
1422 kref_init(&sdp->d_ref);
1423 error = 0;
1424
1425out_unlock:
1426 write_unlock_irqrestore(&sg_index_lock, iflags);
1427 idr_preload_end();
1428
1429 if (error) {
1430 kfree(sdp);
1431 return ERR_PTR(error);
1432 }
1433 return sdp;
1434}
1435
1436static int
1437sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1438{
1439 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1440 struct gendisk *disk;
1441 Sg_device *sdp = NULL;
1442 struct cdev * cdev = NULL;
1443 int error;
1444 unsigned long iflags;
1445
1446 disk = alloc_disk(1);
1447 if (!disk) {
1448 printk(KERN_WARNING "alloc_disk failed\n");
1449 return -ENOMEM;
1450 }
1451 disk->major = SCSI_GENERIC_MAJOR;
1452
1453 error = -ENOMEM;
1454 cdev = cdev_alloc();
1455 if (!cdev) {
1456 printk(KERN_WARNING "cdev_alloc failed\n");
1457 goto out;
1458 }
1459 cdev->owner = THIS_MODULE;
1460 cdev->ops = &sg_fops;
1461
1462 sdp = sg_alloc(disk, scsidp);
1463 if (IS_ERR(sdp)) {
1464 printk(KERN_WARNING "sg_alloc failed\n");
1465 error = PTR_ERR(sdp);
1466 goto out;
1467 }
1468
1469 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1470 if (error)
1471 goto cdev_add_err;
1472
1473 sdp->cdev = cdev;
1474 if (sg_sysfs_valid) {
1475 struct device *sg_class_member;
1476
1477 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1478 MKDEV(SCSI_GENERIC_MAJOR,
1479 sdp->index),
1480 sdp, "%s", disk->disk_name);
1481 if (IS_ERR(sg_class_member)) {
1482 printk(KERN_ERR "sg_add: "
1483 "device_create failed\n");
1484 error = PTR_ERR(sg_class_member);
1485 goto cdev_add_err;
1486 }
1487 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1488 &sg_class_member->kobj, "generic");
1489 if (error)
1490 printk(KERN_ERR "sg_add: unable to make symlink "
1491 "'generic' back to sg%d\n", sdp->index);
1492 } else
1493 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1494
1495 sdev_printk(KERN_NOTICE, scsidp,
1496 "Attached scsi generic sg%d type %d\n", sdp->index,
1497 scsidp->type);
1498
1499 dev_set_drvdata(cl_dev, sdp);
1500
1501 return 0;
1502
1503cdev_add_err:
1504 write_lock_irqsave(&sg_index_lock, iflags);
1505 idr_remove(&sg_index_idr, sdp->index);
1506 write_unlock_irqrestore(&sg_index_lock, iflags);
1507 kfree(sdp);
1508
1509out:
1510 put_disk(disk);
1511 if (cdev)
1512 cdev_del(cdev);
1513 return error;
1514}
1515
1516static void sg_device_destroy(struct kref *kref)
1517{
1518 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1519 unsigned long flags;
1520
1521 /* CAUTION! Note that the device can still be found via idr_find()
1522 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1523 * any other cleanup.
1524 */
1525
1526 write_lock_irqsave(&sg_index_lock, flags);
1527 idr_remove(&sg_index_idr, sdp->index);
1528 write_unlock_irqrestore(&sg_index_lock, flags);
1529
1530 SCSI_LOG_TIMEOUT(3,
1531 printk("sg_device_destroy: %s\n",
1532 sdp->disk->disk_name));
1533
1534 put_disk(sdp->disk);
1535 kfree(sdp);
1536}
1537
1538static void sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1539{
1540 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1541 Sg_device *sdp = dev_get_drvdata(cl_dev);
1542 unsigned long iflags;
1543 Sg_fd *sfp;
1544
1545 if (!sdp || sdp->detached)
1546 return;
1547
1548 SCSI_LOG_TIMEOUT(3, printk("sg_remove: %s\n", sdp->disk->disk_name));
1549
1550 /* Need a write lock to set sdp->detached. */
1551 write_lock_irqsave(&sg_index_lock, iflags);
1552 sdp->detached = 1;
1553 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1554 wake_up_interruptible(&sfp->read_wait);
1555 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1556 }
1557 write_unlock_irqrestore(&sg_index_lock, iflags);
1558
1559 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1560 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1561 cdev_del(sdp->cdev);
1562 sdp->cdev = NULL;
1563
1564 sg_put_dev(sdp);
1565}
1566
1567module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1568module_param_named(def_reserved_size, def_reserved_size, int,
1569 S_IRUGO | S_IWUSR);
1570module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1571
1572MODULE_AUTHOR("Douglas Gilbert");
1573MODULE_DESCRIPTION("SCSI generic (sg) driver");
1574MODULE_LICENSE("GPL");
1575MODULE_VERSION(SG_VERSION_STR);
1576MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1577
1578MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1579 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1580MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1581MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1582
1583static int __init
1584init_sg(void)
1585{
1586 int rc;
1587
1588 if (scatter_elem_sz < PAGE_SIZE) {
1589 scatter_elem_sz = PAGE_SIZE;
1590 scatter_elem_sz_prev = scatter_elem_sz;
1591 }
1592 if (def_reserved_size >= 0)
1593 sg_big_buff = def_reserved_size;
1594 else
1595 def_reserved_size = sg_big_buff;
1596
1597 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1598 SG_MAX_DEVS, "sg");
1599 if (rc)
1600 return rc;
1601 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1602 if ( IS_ERR(sg_sysfs_class) ) {
1603 rc = PTR_ERR(sg_sysfs_class);
1604 goto err_out;
1605 }
1606 sg_sysfs_valid = 1;
1607 rc = scsi_register_interface(&sg_interface);
1608 if (0 == rc) {
1609#ifdef CONFIG_SCSI_PROC_FS
1610 sg_proc_init();
1611#endif /* CONFIG_SCSI_PROC_FS */
1612 return 0;
1613 }
1614 class_destroy(sg_sysfs_class);
1615err_out:
1616 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1617 return rc;
1618}
1619
1620static void __exit
1621exit_sg(void)
1622{
1623#ifdef CONFIG_SCSI_PROC_FS
1624 sg_proc_cleanup();
1625#endif /* CONFIG_SCSI_PROC_FS */
1626 scsi_unregister_interface(&sg_interface);
1627 class_destroy(sg_sysfs_class);
1628 sg_sysfs_valid = 0;
1629 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1630 SG_MAX_DEVS);
1631 idr_destroy(&sg_index_idr);
1632}
1633
1634static int sg_start_req(Sg_request *srp, unsigned char *cmd)
1635{
1636 int res;
1637 struct request *rq;
1638 Sg_fd *sfp = srp->parentfp;
1639 sg_io_hdr_t *hp = &srp->header;
1640 int dxfer_len = (int) hp->dxfer_len;
1641 int dxfer_dir = hp->dxfer_direction;
1642 unsigned int iov_count = hp->iovec_count;
1643 Sg_scatter_hold *req_schp = &srp->data;
1644 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1645 struct request_queue *q = sfp->parentdp->device->request_queue;
1646 struct rq_map_data *md, map_data;
1647 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1648
1649 SCSI_LOG_TIMEOUT(4, printk(KERN_INFO "sg_start_req: dxfer_len=%d\n",
1650 dxfer_len));
1651
1652 rq = blk_get_request(q, rw, GFP_ATOMIC);
1653 if (!rq)
1654 return -ENOMEM;
1655
1656 memcpy(rq->cmd, cmd, hp->cmd_len);
1657
1658 rq->cmd_len = hp->cmd_len;
1659 rq->cmd_type = REQ_TYPE_BLOCK_PC;
1660
1661 srp->rq = rq;
1662 rq->end_io_data = srp;
1663 rq->sense = srp->sense_b;
1664 rq->retries = SG_DEFAULT_RETRIES;
1665
1666 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1667 return 0;
1668
1669 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1670 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1671 !sfp->parentdp->device->host->unchecked_isa_dma &&
1672 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1673 md = NULL;
1674 else
1675 md = &map_data;
1676
1677 if (md) {
1678 if (!sg_res_in_use(sfp) && dxfer_len <= rsv_schp->bufflen)
1679 sg_link_reserve(sfp, srp, dxfer_len);
1680 else {
1681 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1682 if (res)
1683 return res;
1684 }
1685
1686 md->pages = req_schp->pages;
1687 md->page_order = req_schp->page_order;
1688 md->nr_entries = req_schp->k_use_sg;
1689 md->offset = 0;
1690 md->null_mapped = hp->dxferp ? 0 : 1;
1691 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1692 md->from_user = 1;
1693 else
1694 md->from_user = 0;
1695 }
1696
1697 if (iov_count) {
1698 int len, size = sizeof(struct sg_iovec) * iov_count;
1699 struct iovec *iov;
1700
1701 iov = memdup_user(hp->dxferp, size);
1702 if (IS_ERR(iov))
1703 return PTR_ERR(iov);
1704
1705 len = iov_length(iov, iov_count);
1706 if (hp->dxfer_len < len) {
1707 iov_count = iov_shorten(iov, iov_count, hp->dxfer_len);
1708 len = hp->dxfer_len;
1709 }
1710
1711 res = blk_rq_map_user_iov(q, rq, md, (struct sg_iovec *)iov,
1712 iov_count,
1713 len, GFP_ATOMIC);
1714 kfree(iov);
1715 } else
1716 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1717 hp->dxfer_len, GFP_ATOMIC);
1718
1719 if (!res) {
1720 srp->bio = rq->bio;
1721
1722 if (!md) {
1723 req_schp->dio_in_use = 1;
1724 hp->info |= SG_INFO_DIRECT_IO;
1725 }
1726 }
1727 return res;
1728}
1729
1730static int sg_finish_rem_req(Sg_request * srp)
1731{
1732 int ret = 0;
1733
1734 Sg_fd *sfp = srp->parentfp;
1735 Sg_scatter_hold *req_schp = &srp->data;
1736
1737 SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1738 if (srp->rq) {
1739 if (srp->bio)
1740 ret = blk_rq_unmap_user(srp->bio);
1741
1742 blk_put_request(srp->rq);
1743 }
1744
1745 if (srp->res_used)
1746 sg_unlink_reserve(sfp, srp);
1747 else
1748 sg_remove_scat(req_schp);
1749
1750 sg_remove_request(sfp, srp);
1751
1752 return ret;
1753}
1754
1755static int
1756sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1757{
1758 int sg_bufflen = tablesize * sizeof(struct page *);
1759 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1760
1761 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1762 if (!schp->pages)
1763 return -ENOMEM;
1764 schp->sglist_len = sg_bufflen;
1765 return tablesize; /* number of scat_gath elements allocated */
1766}
1767
1768static int
1769sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1770{
1771 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1772 int sg_tablesize = sfp->parentdp->sg_tablesize;
1773 int blk_size = buff_size, order;
1774 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1775
1776 if (blk_size < 0)
1777 return -EFAULT;
1778 if (0 == blk_size)
1779 ++blk_size; /* don't know why */
1780 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1781 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1782 SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1783 buff_size, blk_size));
1784
1785 /* N.B. ret_sz carried into this block ... */
1786 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1787 if (mx_sc_elems < 0)
1788 return mx_sc_elems; /* most likely -ENOMEM */
1789
1790 num = scatter_elem_sz;
1791 if (unlikely(num != scatter_elem_sz_prev)) {
1792 if (num < PAGE_SIZE) {
1793 scatter_elem_sz = PAGE_SIZE;
1794 scatter_elem_sz_prev = PAGE_SIZE;
1795 } else
1796 scatter_elem_sz_prev = num;
1797 }
1798
1799 if (sfp->low_dma)
1800 gfp_mask |= GFP_DMA;
1801
1802 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1803 gfp_mask |= __GFP_ZERO;
1804
1805 order = get_order(num);
1806retry:
1807 ret_sz = 1 << (PAGE_SHIFT + order);
1808
1809 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1810 k++, rem_sz -= ret_sz) {
1811
1812 num = (rem_sz > scatter_elem_sz_prev) ?
1813 scatter_elem_sz_prev : rem_sz;
1814
1815 schp->pages[k] = alloc_pages(gfp_mask, order);
1816 if (!schp->pages[k])
1817 goto out;
1818
1819 if (num == scatter_elem_sz_prev) {
1820 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1821 scatter_elem_sz = ret_sz;
1822 scatter_elem_sz_prev = ret_sz;
1823 }
1824 }
1825
1826 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1827 "ret_sz=%d\n", k, num, ret_sz));
1828 } /* end of for loop */
1829
1830 schp->page_order = order;
1831 schp->k_use_sg = k;
1832 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1833 "rem_sz=%d\n", k, rem_sz));
1834
1835 schp->bufflen = blk_size;
1836 if (rem_sz > 0) /* must have failed */
1837 return -ENOMEM;
1838 return 0;
1839out:
1840 for (i = 0; i < k; i++)
1841 __free_pages(schp->pages[i], order);
1842
1843 if (--order >= 0)
1844 goto retry;
1845
1846 return -ENOMEM;
1847}
1848
1849static void
1850sg_remove_scat(Sg_scatter_hold * schp)
1851{
1852 SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1853 if (schp->pages && schp->sglist_len > 0) {
1854 if (!schp->dio_in_use) {
1855 int k;
1856
1857 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1858 SCSI_LOG_TIMEOUT(5, printk(
1859 "sg_remove_scat: k=%d, pg=0x%p\n",
1860 k, schp->pages[k]));
1861 __free_pages(schp->pages[k], schp->page_order);
1862 }
1863
1864 kfree(schp->pages);
1865 }
1866 }
1867 memset(schp, 0, sizeof (*schp));
1868}
1869
1870static int
1871sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1872{
1873 Sg_scatter_hold *schp = &srp->data;
1874 int k, num;
1875
1876 SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
1877 num_read_xfer));
1878 if ((!outp) || (num_read_xfer <= 0))
1879 return 0;
1880
1881 num = 1 << (PAGE_SHIFT + schp->page_order);
1882 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1883 if (num > num_read_xfer) {
1884 if (__copy_to_user(outp, page_address(schp->pages[k]),
1885 num_read_xfer))
1886 return -EFAULT;
1887 break;
1888 } else {
1889 if (__copy_to_user(outp, page_address(schp->pages[k]),
1890 num))
1891 return -EFAULT;
1892 num_read_xfer -= num;
1893 if (num_read_xfer <= 0)
1894 break;
1895 outp += num;
1896 }
1897 }
1898
1899 return 0;
1900}
1901
1902static void
1903sg_build_reserve(Sg_fd * sfp, int req_size)
1904{
1905 Sg_scatter_hold *schp = &sfp->reserve;
1906
1907 SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
1908 do {
1909 if (req_size < PAGE_SIZE)
1910 req_size = PAGE_SIZE;
1911 if (0 == sg_build_indirect(schp, sfp, req_size))
1912 return;
1913 else
1914 sg_remove_scat(schp);
1915 req_size >>= 1; /* divide by 2 */
1916 } while (req_size > (PAGE_SIZE / 2));
1917}
1918
1919static void
1920sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1921{
1922 Sg_scatter_hold *req_schp = &srp->data;
1923 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1924 int k, num, rem;
1925
1926 srp->res_used = 1;
1927 SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
1928 rem = size;
1929
1930 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1931 for (k = 0; k < rsv_schp->k_use_sg; k++) {
1932 if (rem <= num) {
1933 req_schp->k_use_sg = k + 1;
1934 req_schp->sglist_len = rsv_schp->sglist_len;
1935 req_schp->pages = rsv_schp->pages;
1936
1937 req_schp->bufflen = size;
1938 req_schp->page_order = rsv_schp->page_order;
1939 break;
1940 } else
1941 rem -= num;
1942 }
1943
1944 if (k >= rsv_schp->k_use_sg)
1945 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
1946}
1947
1948static void
1949sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
1950{
1951 Sg_scatter_hold *req_schp = &srp->data;
1952
1953 SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
1954 (int) req_schp->k_use_sg));
1955 req_schp->k_use_sg = 0;
1956 req_schp->bufflen = 0;
1957 req_schp->pages = NULL;
1958 req_schp->page_order = 0;
1959 req_schp->sglist_len = 0;
1960 sfp->save_scat_len = 0;
1961 srp->res_used = 0;
1962}
1963
1964static Sg_request *
1965sg_get_rq_mark(Sg_fd * sfp, int pack_id)
1966{
1967 Sg_request *resp;
1968 unsigned long iflags;
1969
1970 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1971 for (resp = sfp->headrp; resp; resp = resp->nextrp) {
1972 /* look for requests that are ready + not SG_IO owned */
1973 if ((1 == resp->done) && (!resp->sg_io_owned) &&
1974 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
1975 resp->done = 2; /* guard against other readers */
1976 break;
1977 }
1978 }
1979 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1980 return resp;
1981}
1982
1983/* always adds to end of list */
1984static Sg_request *
1985sg_add_request(Sg_fd * sfp)
1986{
1987 int k;
1988 unsigned long iflags;
1989 Sg_request *resp;
1990 Sg_request *rp = sfp->req_arr;
1991
1992 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1993 resp = sfp->headrp;
1994 if (!resp) {
1995 memset(rp, 0, sizeof (Sg_request));
1996 rp->parentfp = sfp;
1997 resp = rp;
1998 sfp->headrp = resp;
1999 } else {
2000 if (0 == sfp->cmd_q)
2001 resp = NULL; /* command queuing disallowed */
2002 else {
2003 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2004 if (!rp->parentfp)
2005 break;
2006 }
2007 if (k < SG_MAX_QUEUE) {
2008 memset(rp, 0, sizeof (Sg_request));
2009 rp->parentfp = sfp;
2010 while (resp->nextrp)
2011 resp = resp->nextrp;
2012 resp->nextrp = rp;
2013 resp = rp;
2014 } else
2015 resp = NULL;
2016 }
2017 }
2018 if (resp) {
2019 resp->nextrp = NULL;
2020 resp->header.duration = jiffies_to_msecs(jiffies);
2021 }
2022 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2023 return resp;
2024}
2025
2026/* Return of 1 for found; 0 for not found */
2027static int
2028sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2029{
2030 Sg_request *prev_rp;
2031 Sg_request *rp;
2032 unsigned long iflags;
2033 int res = 0;
2034
2035 if ((!sfp) || (!srp) || (!sfp->headrp))
2036 return res;
2037 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2038 prev_rp = sfp->headrp;
2039 if (srp == prev_rp) {
2040 sfp->headrp = prev_rp->nextrp;
2041 prev_rp->parentfp = NULL;
2042 res = 1;
2043 } else {
2044 while ((rp = prev_rp->nextrp)) {
2045 if (srp == rp) {
2046 prev_rp->nextrp = rp->nextrp;
2047 rp->parentfp = NULL;
2048 res = 1;
2049 break;
2050 }
2051 prev_rp = rp;
2052 }
2053 }
2054 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2055 return res;
2056}
2057
2058static Sg_fd *
2059sg_add_sfp(Sg_device * sdp, int dev)
2060{
2061 Sg_fd *sfp;
2062 unsigned long iflags;
2063 int bufflen;
2064
2065 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2066 if (!sfp)
2067 return NULL;
2068
2069 init_waitqueue_head(&sfp->read_wait);
2070 rwlock_init(&sfp->rq_list_lock);
2071
2072 kref_init(&sfp->f_ref);
2073 sfp->timeout = SG_DEFAULT_TIMEOUT;
2074 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2075 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2076 sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2077 sdp->device->host->unchecked_isa_dma : 1;
2078 sfp->cmd_q = SG_DEF_COMMAND_Q;
2079 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2080 sfp->parentdp = sdp;
2081 write_lock_irqsave(&sg_index_lock, iflags);
2082 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2083 write_unlock_irqrestore(&sg_index_lock, iflags);
2084 SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2085 if (unlikely(sg_big_buff != def_reserved_size))
2086 sg_big_buff = def_reserved_size;
2087
2088 bufflen = min_t(int, sg_big_buff,
2089 queue_max_sectors(sdp->device->request_queue) * 512);
2090 sg_build_reserve(sfp, bufflen);
2091 SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2092 sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2093
2094 kref_get(&sdp->d_ref);
2095 __module_get(THIS_MODULE);
2096 return sfp;
2097}
2098
2099static void sg_remove_sfp_usercontext(struct work_struct *work)
2100{
2101 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2102 struct sg_device *sdp = sfp->parentdp;
2103
2104 /* Cleanup any responses which were never read(). */
2105 while (sfp->headrp)
2106 sg_finish_rem_req(sfp->headrp);
2107
2108 if (sfp->reserve.bufflen > 0) {
2109 SCSI_LOG_TIMEOUT(6,
2110 printk("sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2111 (int) sfp->reserve.bufflen,
2112 (int) sfp->reserve.k_use_sg));
2113 sg_remove_scat(&sfp->reserve);
2114 }
2115
2116 SCSI_LOG_TIMEOUT(6,
2117 printk("sg_remove_sfp: %s, sfp=0x%p\n",
2118 sdp->disk->disk_name,
2119 sfp));
2120 kfree(sfp);
2121
2122 scsi_device_put(sdp->device);
2123 sg_put_dev(sdp);
2124 module_put(THIS_MODULE);
2125}
2126
2127static void sg_remove_sfp(struct kref *kref)
2128{
2129 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2130 struct sg_device *sdp = sfp->parentdp;
2131 unsigned long iflags;
2132
2133 write_lock_irqsave(&sg_index_lock, iflags);
2134 list_del(&sfp->sfd_siblings);
2135 write_unlock_irqrestore(&sg_index_lock, iflags);
2136 wake_up_interruptible(&sdp->o_excl_wait);
2137
2138 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2139 schedule_work(&sfp->ew.work);
2140}
2141
2142static int
2143sg_res_in_use(Sg_fd * sfp)
2144{
2145 const Sg_request *srp;
2146 unsigned long iflags;
2147
2148 read_lock_irqsave(&sfp->rq_list_lock, iflags);
2149 for (srp = sfp->headrp; srp; srp = srp->nextrp)
2150 if (srp->res_used)
2151 break;
2152 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2153 return srp ? 1 : 0;
2154}
2155
2156#ifdef CONFIG_SCSI_PROC_FS
2157static int
2158sg_idr_max_id(int id, void *p, void *data)
2159{
2160 int *k = data;
2161
2162 if (*k < id)
2163 *k = id;
2164
2165 return 0;
2166}
2167
2168static int
2169sg_last_dev(void)
2170{
2171 int k = -1;
2172 unsigned long iflags;
2173
2174 read_lock_irqsave(&sg_index_lock, iflags);
2175 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2176 read_unlock_irqrestore(&sg_index_lock, iflags);
2177 return k + 1; /* origin 1 */
2178}
2179#endif
2180
2181/* must be called with sg_index_lock held */
2182static Sg_device *sg_lookup_dev(int dev)
2183{
2184 return idr_find(&sg_index_idr, dev);
2185}
2186
2187static Sg_device *sg_get_dev(int dev)
2188{
2189 struct sg_device *sdp;
2190 unsigned long flags;
2191
2192 read_lock_irqsave(&sg_index_lock, flags);
2193 sdp = sg_lookup_dev(dev);
2194 if (!sdp)
2195 sdp = ERR_PTR(-ENXIO);
2196 else if (sdp->detached) {
2197 /* If sdp->detached, then the refcount may already be 0, in
2198 * which case it would be a bug to do kref_get().
2199 */
2200 sdp = ERR_PTR(-ENODEV);
2201 } else
2202 kref_get(&sdp->d_ref);
2203 read_unlock_irqrestore(&sg_index_lock, flags);
2204
2205 return sdp;
2206}
2207
2208static void sg_put_dev(struct sg_device *sdp)
2209{
2210 kref_put(&sdp->d_ref, sg_device_destroy);
2211}
2212
2213#ifdef CONFIG_SCSI_PROC_FS
2214
2215static struct proc_dir_entry *sg_proc_sgp = NULL;
2216
2217static char sg_proc_sg_dirname[] = "scsi/sg";
2218
2219static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2220
2221static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2222static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2223 size_t count, loff_t *off);
2224static const struct file_operations adio_fops = {
2225 .owner = THIS_MODULE,
2226 .open = sg_proc_single_open_adio,
2227 .read = seq_read,
2228 .llseek = seq_lseek,
2229 .write = sg_proc_write_adio,
2230 .release = single_release,
2231};
2232
2233static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2234static ssize_t sg_proc_write_dressz(struct file *filp,
2235 const char __user *buffer, size_t count, loff_t *off);
2236static const struct file_operations dressz_fops = {
2237 .owner = THIS_MODULE,
2238 .open = sg_proc_single_open_dressz,
2239 .read = seq_read,
2240 .llseek = seq_lseek,
2241 .write = sg_proc_write_dressz,
2242 .release = single_release,
2243};
2244
2245static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2246static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2247static const struct file_operations version_fops = {
2248 .owner = THIS_MODULE,
2249 .open = sg_proc_single_open_version,
2250 .read = seq_read,
2251 .llseek = seq_lseek,
2252 .release = single_release,
2253};
2254
2255static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2256static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2257static const struct file_operations devhdr_fops = {
2258 .owner = THIS_MODULE,
2259 .open = sg_proc_single_open_devhdr,
2260 .read = seq_read,
2261 .llseek = seq_lseek,
2262 .release = single_release,
2263};
2264
2265static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2266static int sg_proc_open_dev(struct inode *inode, struct file *file);
2267static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2268static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2269static void dev_seq_stop(struct seq_file *s, void *v);
2270static const struct file_operations dev_fops = {
2271 .owner = THIS_MODULE,
2272 .open = sg_proc_open_dev,
2273 .read = seq_read,
2274 .llseek = seq_lseek,
2275 .release = seq_release,
2276};
2277static const struct seq_operations dev_seq_ops = {
2278 .start = dev_seq_start,
2279 .next = dev_seq_next,
2280 .stop = dev_seq_stop,
2281 .show = sg_proc_seq_show_dev,
2282};
2283
2284static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2285static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2286static const struct file_operations devstrs_fops = {
2287 .owner = THIS_MODULE,
2288 .open = sg_proc_open_devstrs,
2289 .read = seq_read,
2290 .llseek = seq_lseek,
2291 .release = seq_release,
2292};
2293static const struct seq_operations devstrs_seq_ops = {
2294 .start = dev_seq_start,
2295 .next = dev_seq_next,
2296 .stop = dev_seq_stop,
2297 .show = sg_proc_seq_show_devstrs,
2298};
2299
2300static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2301static int sg_proc_open_debug(struct inode *inode, struct file *file);
2302static const struct file_operations debug_fops = {
2303 .owner = THIS_MODULE,
2304 .open = sg_proc_open_debug,
2305 .read = seq_read,
2306 .llseek = seq_lseek,
2307 .release = seq_release,
2308};
2309static const struct seq_operations debug_seq_ops = {
2310 .start = dev_seq_start,
2311 .next = dev_seq_next,
2312 .stop = dev_seq_stop,
2313 .show = sg_proc_seq_show_debug,
2314};
2315
2316
2317struct sg_proc_leaf {
2318 const char * name;
2319 const struct file_operations * fops;
2320};
2321
2322static const struct sg_proc_leaf sg_proc_leaf_arr[] = {
2323 {"allow_dio", &adio_fops},
2324 {"debug", &debug_fops},
2325 {"def_reserved_size", &dressz_fops},
2326 {"device_hdr", &devhdr_fops},
2327 {"devices", &dev_fops},
2328 {"device_strs", &devstrs_fops},
2329 {"version", &version_fops}
2330};
2331
2332static int
2333sg_proc_init(void)
2334{
2335 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2336 int k;
2337
2338 sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2339 if (!sg_proc_sgp)
2340 return 1;
2341 for (k = 0; k < num_leaves; ++k) {
2342 const struct sg_proc_leaf *leaf = &sg_proc_leaf_arr[k];
2343 umode_t mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2344 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2345 }
2346 return 0;
2347}
2348
2349static void
2350sg_proc_cleanup(void)
2351{
2352 int k;
2353 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2354
2355 if (!sg_proc_sgp)
2356 return;
2357 for (k = 0; k < num_leaves; ++k)
2358 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2359 remove_proc_entry(sg_proc_sg_dirname, NULL);
2360}
2361
2362
2363static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2364{
2365 seq_printf(s, "%d\n", *((int *)s->private));
2366 return 0;
2367}
2368
2369static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2370{
2371 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2372}
2373
2374static ssize_t
2375sg_proc_write_adio(struct file *filp, const char __user *buffer,
2376 size_t count, loff_t *off)
2377{
2378 int err;
2379 unsigned long num;
2380
2381 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2382 return -EACCES;
2383 err = kstrtoul_from_user(buffer, count, 0, &num);
2384 if (err)
2385 return err;
2386 sg_allow_dio = num ? 1 : 0;
2387 return count;
2388}
2389
2390static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2391{
2392 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2393}
2394
2395static ssize_t
2396sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2397 size_t count, loff_t *off)
2398{
2399 int err;
2400 unsigned long k = ULONG_MAX;
2401
2402 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2403 return -EACCES;
2404
2405 err = kstrtoul_from_user(buffer, count, 0, &k);
2406 if (err)
2407 return err;
2408 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2409 sg_big_buff = k;
2410 return count;
2411 }
2412 return -ERANGE;
2413}
2414
2415static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2416{
2417 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2418 sg_version_date);
2419 return 0;
2420}
2421
2422static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2423{
2424 return single_open(file, sg_proc_seq_show_version, NULL);
2425}
2426
2427static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2428{
2429 seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2430 "online\n");
2431 return 0;
2432}
2433
2434static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2435{
2436 return single_open(file, sg_proc_seq_show_devhdr, NULL);
2437}
2438
2439struct sg_proc_deviter {
2440 loff_t index;
2441 size_t max;
2442};
2443
2444static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2445{
2446 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2447
2448 s->private = it;
2449 if (! it)
2450 return NULL;
2451
2452 it->index = *pos;
2453 it->max = sg_last_dev();
2454 if (it->index >= it->max)
2455 return NULL;
2456 return it;
2457}
2458
2459static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2460{
2461 struct sg_proc_deviter * it = s->private;
2462
2463 *pos = ++it->index;
2464 return (it->index < it->max) ? it : NULL;
2465}
2466
2467static void dev_seq_stop(struct seq_file *s, void *v)
2468{
2469 kfree(s->private);
2470}
2471
2472static int sg_proc_open_dev(struct inode *inode, struct file *file)
2473{
2474 return seq_open(file, &dev_seq_ops);
2475}
2476
2477static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2478{
2479 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2480 Sg_device *sdp;
2481 struct scsi_device *scsidp;
2482 unsigned long iflags;
2483
2484 read_lock_irqsave(&sg_index_lock, iflags);
2485 sdp = it ? sg_lookup_dev(it->index) : NULL;
2486 if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2487 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2488 scsidp->host->host_no, scsidp->channel,
2489 scsidp->id, scsidp->lun, (int) scsidp->type,
2490 1,
2491 (int) scsidp->queue_depth,
2492 (int) scsidp->device_busy,
2493 (int) scsi_device_online(scsidp));
2494 else
2495 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2496 read_unlock_irqrestore(&sg_index_lock, iflags);
2497 return 0;
2498}
2499
2500static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2501{
2502 return seq_open(file, &devstrs_seq_ops);
2503}
2504
2505static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2506{
2507 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2508 Sg_device *sdp;
2509 struct scsi_device *scsidp;
2510 unsigned long iflags;
2511
2512 read_lock_irqsave(&sg_index_lock, iflags);
2513 sdp = it ? sg_lookup_dev(it->index) : NULL;
2514 if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2515 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2516 scsidp->vendor, scsidp->model, scsidp->rev);
2517 else
2518 seq_printf(s, "<no active device>\n");
2519 read_unlock_irqrestore(&sg_index_lock, iflags);
2520 return 0;
2521}
2522
2523/* must be called while holding sg_index_lock */
2524static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2525{
2526 int k, m, new_interface, blen, usg;
2527 Sg_request *srp;
2528 Sg_fd *fp;
2529 const sg_io_hdr_t *hp;
2530 const char * cp;
2531 unsigned int ms;
2532
2533 k = 0;
2534 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2535 k++;
2536 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2537 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2538 "(res)sgat=%d low_dma=%d\n", k,
2539 jiffies_to_msecs(fp->timeout),
2540 fp->reserve.bufflen,
2541 (int) fp->reserve.k_use_sg,
2542 (int) fp->low_dma);
2543 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2544 (int) fp->cmd_q, (int) fp->force_packid,
2545 (int) fp->keep_orphan);
2546 for (m = 0, srp = fp->headrp;
2547 srp != NULL;
2548 ++m, srp = srp->nextrp) {
2549 hp = &srp->header;
2550 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2551 if (srp->res_used) {
2552 if (new_interface &&
2553 (SG_FLAG_MMAP_IO & hp->flags))
2554 cp = " mmap>> ";
2555 else
2556 cp = " rb>> ";
2557 } else {
2558 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2559 cp = " dio>> ";
2560 else
2561 cp = " ";
2562 }
2563 seq_printf(s, cp);
2564 blen = srp->data.bufflen;
2565 usg = srp->data.k_use_sg;
2566 seq_printf(s, srp->done ?
2567 ((1 == srp->done) ? "rcv:" : "fin:")
2568 : "act:");
2569 seq_printf(s, " id=%d blen=%d",
2570 srp->header.pack_id, blen);
2571 if (srp->done)
2572 seq_printf(s, " dur=%d", hp->duration);
2573 else {
2574 ms = jiffies_to_msecs(jiffies);
2575 seq_printf(s, " t_o/elap=%d/%d",
2576 (new_interface ? hp->timeout :
2577 jiffies_to_msecs(fp->timeout)),
2578 (ms > hp->duration ? ms - hp->duration : 0));
2579 }
2580 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2581 (int) srp->data.cmd_opcode);
2582 }
2583 if (0 == m)
2584 seq_printf(s, " No requests active\n");
2585 read_unlock(&fp->rq_list_lock);
2586 }
2587}
2588
2589static int sg_proc_open_debug(struct inode *inode, struct file *file)
2590{
2591 return seq_open(file, &debug_seq_ops);
2592}
2593
2594static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2595{
2596 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2597 Sg_device *sdp;
2598 unsigned long iflags;
2599
2600 if (it && (0 == it->index)) {
2601 seq_printf(s, "max_active_device=%d(origin 1)\n",
2602 (int)it->max);
2603 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2604 }
2605
2606 read_lock_irqsave(&sg_index_lock, iflags);
2607 sdp = it ? sg_lookup_dev(it->index) : NULL;
2608 if (sdp && !list_empty(&sdp->sfds)) {
2609 struct scsi_device *scsidp = sdp->device;
2610
2611 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2612 if (sdp->detached)
2613 seq_printf(s, "detached pending close ");
2614 else
2615 seq_printf
2616 (s, "scsi%d chan=%d id=%d lun=%d em=%d",
2617 scsidp->host->host_no,
2618 scsidp->channel, scsidp->id,
2619 scsidp->lun,
2620 scsidp->host->hostt->emulated);
2621 seq_printf(s, " sg_tablesize=%d excl=%d\n",
2622 sdp->sg_tablesize, get_exclude(sdp));
2623 sg_proc_debug_helper(s, sdp);
2624 }
2625 read_unlock_irqrestore(&sg_index_lock, iflags);
2626 return 0;
2627}
2628
2629#endif /* CONFIG_SCSI_PROC_FS */
2630
2631module_init(init_sg);
2632module_exit(exit_sg);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * History:
4 * Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
5 * to allow user process control of SCSI devices.
6 * Development Sponsored by Killy Corp. NY NY
7 *
8 * Original driver (sg.c):
9 * Copyright (C) 1992 Lawrence Foard
10 * Version 2 and 3 extensions to driver:
11 * Copyright (C) 1998 - 2014 Douglas Gilbert
12 */
13
14static int sg_version_num = 30536; /* 2 digits for each component */
15#define SG_VERSION_STR "3.5.36"
16
17/*
18 * D. P. Gilbert (dgilbert@interlog.com), notes:
19 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
20 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING
21 * (otherwise the macros compile to empty statements).
22 *
23 */
24#include <linux/module.h>
25
26#include <linux/fs.h>
27#include <linux/kernel.h>
28#include <linux/sched.h>
29#include <linux/string.h>
30#include <linux/mm.h>
31#include <linux/errno.h>
32#include <linux/mtio.h>
33#include <linux/ioctl.h>
34#include <linux/slab.h>
35#include <linux/fcntl.h>
36#include <linux/init.h>
37#include <linux/poll.h>
38#include <linux/moduleparam.h>
39#include <linux/cdev.h>
40#include <linux/idr.h>
41#include <linux/seq_file.h>
42#include <linux/blkdev.h>
43#include <linux/delay.h>
44#include <linux/blktrace_api.h>
45#include <linux/mutex.h>
46#include <linux/atomic.h>
47#include <linux/ratelimit.h>
48#include <linux/uio.h>
49#include <linux/cred.h> /* for sg_check_file_access() */
50
51#include "scsi.h"
52#include <scsi/scsi_dbg.h>
53#include <scsi/scsi_host.h>
54#include <scsi/scsi_driver.h>
55#include <scsi/scsi_ioctl.h>
56#include <scsi/sg.h>
57
58#include "scsi_logging.h"
59
60#ifdef CONFIG_SCSI_PROC_FS
61#include <linux/proc_fs.h>
62static char *sg_version_date = "20140603";
63
64static int sg_proc_init(void);
65#endif
66
67#define SG_ALLOW_DIO_DEF 0
68
69#define SG_MAX_DEVS 32768
70
71/* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type
72 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater
73 * than 16 bytes are "variable length" whose length is a multiple of 4
74 */
75#define SG_MAX_CDB_SIZE 252
76
77#define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
78
79int sg_big_buff = SG_DEF_RESERVED_SIZE;
80/* N.B. This variable is readable and writeable via
81 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
82 of this size (or less if there is not enough memory) will be reserved
83 for use by this file descriptor. [Deprecated usage: this variable is also
84 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
85 the kernel (i.e. it is not a module).] */
86static int def_reserved_size = -1; /* picks up init parameter */
87static int sg_allow_dio = SG_ALLOW_DIO_DEF;
88
89static int scatter_elem_sz = SG_SCATTER_SZ;
90static int scatter_elem_sz_prev = SG_SCATTER_SZ;
91
92#define SG_SECTOR_SZ 512
93
94static int sg_add_device(struct device *, struct class_interface *);
95static void sg_remove_device(struct device *, struct class_interface *);
96
97static DEFINE_IDR(sg_index_idr);
98static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
99 file descriptor list for device */
100
101static struct class_interface sg_interface = {
102 .add_dev = sg_add_device,
103 .remove_dev = sg_remove_device,
104};
105
106typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
107 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
108 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
109 unsigned bufflen; /* Size of (aggregate) data buffer */
110 struct page **pages;
111 int page_order;
112 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
113 unsigned char cmd_opcode; /* first byte of command */
114} Sg_scatter_hold;
115
116struct sg_device; /* forward declarations */
117struct sg_fd;
118
119typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
120 struct list_head entry; /* list entry */
121 struct sg_fd *parentfp; /* NULL -> not in use */
122 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
123 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
124 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
125 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
126 char orphan; /* 1 -> drop on sight, 0 -> normal */
127 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
128 /* done protected by rq_list_lock */
129 char done; /* 0->before bh, 1->before read, 2->read */
130 struct request *rq;
131 struct bio *bio;
132 struct execute_work ew;
133} Sg_request;
134
135typedef struct sg_fd { /* holds the state of a file descriptor */
136 struct list_head sfd_siblings; /* protected by device's sfd_lock */
137 struct sg_device *parentdp; /* owning device */
138 wait_queue_head_t read_wait; /* queue read until command done */
139 rwlock_t rq_list_lock; /* protect access to list in req_arr */
140 struct mutex f_mutex; /* protect against changes in this fd */
141 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
142 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
143 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
144 struct list_head rq_list; /* head of request list */
145 struct fasync_struct *async_qp; /* used by asynchronous notification */
146 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
147 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
148 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
149 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
150 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
151 char mmap_called; /* 0 -> mmap() never called on this fd */
152 char res_in_use; /* 1 -> 'reserve' array in use */
153 struct kref f_ref;
154 struct execute_work ew;
155} Sg_fd;
156
157typedef struct sg_device { /* holds the state of each scsi generic device */
158 struct scsi_device *device;
159 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */
160 struct mutex open_rel_lock; /* held when in open() or release() */
161 int sg_tablesize; /* adapter's max scatter-gather table size */
162 u32 index; /* device index number */
163 struct list_head sfds;
164 rwlock_t sfd_lock; /* protect access to sfd list */
165 atomic_t detaching; /* 0->device usable, 1->device detaching */
166 bool exclude; /* 1->open(O_EXCL) succeeded and is active */
167 int open_cnt; /* count of opens (perhaps < num(sfds) ) */
168 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
169 struct gendisk *disk;
170 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
171 struct kref d_ref;
172} Sg_device;
173
174/* tasklet or soft irq callback */
175static void sg_rq_end_io(struct request *rq, blk_status_t status);
176static int sg_start_req(Sg_request *srp, unsigned char *cmd);
177static int sg_finish_rem_req(Sg_request * srp);
178static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
179static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
180 Sg_request * srp);
181static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
182 const char __user *buf, size_t count, int blocking,
183 int read_only, int sg_io_owned, Sg_request **o_srp);
184static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
185 unsigned char *cmnd, int timeout, int blocking);
186static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
187static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
188static void sg_build_reserve(Sg_fd * sfp, int req_size);
189static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
190static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
191static Sg_fd *sg_add_sfp(Sg_device * sdp);
192static void sg_remove_sfp(struct kref *);
193static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
194static Sg_request *sg_add_request(Sg_fd * sfp);
195static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
196static Sg_device *sg_get_dev(int dev);
197static void sg_device_destroy(struct kref *kref);
198
199#define SZ_SG_HEADER sizeof(struct sg_header)
200#define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
201#define SZ_SG_IOVEC sizeof(sg_iovec_t)
202#define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
203
204#define sg_printk(prefix, sdp, fmt, a...) \
205 sdev_prefix_printk(prefix, (sdp)->device, \
206 (sdp)->disk->disk_name, fmt, ##a)
207
208/*
209 * The SCSI interfaces that use read() and write() as an asynchronous variant of
210 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways
211 * to trigger read() and write() calls from various contexts with elevated
212 * privileges. This can lead to kernel memory corruption (e.g. if these
213 * interfaces are called through splice()) and privilege escalation inside
214 * userspace (e.g. if a process with access to such a device passes a file
215 * descriptor to a SUID binary as stdin/stdout/stderr).
216 *
217 * This function provides protection for the legacy API by restricting the
218 * calling context.
219 */
220static int sg_check_file_access(struct file *filp, const char *caller)
221{
222 if (filp->f_cred != current_real_cred()) {
223 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
224 caller, task_tgid_vnr(current), current->comm);
225 return -EPERM;
226 }
227 if (uaccess_kernel()) {
228 pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n",
229 caller, task_tgid_vnr(current), current->comm);
230 return -EACCES;
231 }
232 return 0;
233}
234
235static int sg_allow_access(struct file *filp, unsigned char *cmd)
236{
237 struct sg_fd *sfp = filp->private_data;
238
239 if (sfp->parentdp->device->type == TYPE_SCANNER)
240 return 0;
241
242 return blk_verify_command(cmd, filp->f_mode);
243}
244
245static int
246open_wait(Sg_device *sdp, int flags)
247{
248 int retval = 0;
249
250 if (flags & O_EXCL) {
251 while (sdp->open_cnt > 0) {
252 mutex_unlock(&sdp->open_rel_lock);
253 retval = wait_event_interruptible(sdp->open_wait,
254 (atomic_read(&sdp->detaching) ||
255 !sdp->open_cnt));
256 mutex_lock(&sdp->open_rel_lock);
257
258 if (retval) /* -ERESTARTSYS */
259 return retval;
260 if (atomic_read(&sdp->detaching))
261 return -ENODEV;
262 }
263 } else {
264 while (sdp->exclude) {
265 mutex_unlock(&sdp->open_rel_lock);
266 retval = wait_event_interruptible(sdp->open_wait,
267 (atomic_read(&sdp->detaching) ||
268 !sdp->exclude));
269 mutex_lock(&sdp->open_rel_lock);
270
271 if (retval) /* -ERESTARTSYS */
272 return retval;
273 if (atomic_read(&sdp->detaching))
274 return -ENODEV;
275 }
276 }
277
278 return retval;
279}
280
281/* Returns 0 on success, else a negated errno value */
282static int
283sg_open(struct inode *inode, struct file *filp)
284{
285 int dev = iminor(inode);
286 int flags = filp->f_flags;
287 struct request_queue *q;
288 Sg_device *sdp;
289 Sg_fd *sfp;
290 int retval;
291
292 nonseekable_open(inode, filp);
293 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
294 return -EPERM; /* Can't lock it with read only access */
295 sdp = sg_get_dev(dev);
296 if (IS_ERR(sdp))
297 return PTR_ERR(sdp);
298
299 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
300 "sg_open: flags=0x%x\n", flags));
301
302 /* This driver's module count bumped by fops_get in <linux/fs.h> */
303 /* Prevent the device driver from vanishing while we sleep */
304 retval = scsi_device_get(sdp->device);
305 if (retval)
306 goto sg_put;
307
308 retval = scsi_autopm_get_device(sdp->device);
309 if (retval)
310 goto sdp_put;
311
312 /* scsi_block_when_processing_errors() may block so bypass
313 * check if O_NONBLOCK. Permits SCSI commands to be issued
314 * during error recovery. Tread carefully. */
315 if (!((flags & O_NONBLOCK) ||
316 scsi_block_when_processing_errors(sdp->device))) {
317 retval = -ENXIO;
318 /* we are in error recovery for this device */
319 goto error_out;
320 }
321
322 mutex_lock(&sdp->open_rel_lock);
323 if (flags & O_NONBLOCK) {
324 if (flags & O_EXCL) {
325 if (sdp->open_cnt > 0) {
326 retval = -EBUSY;
327 goto error_mutex_locked;
328 }
329 } else {
330 if (sdp->exclude) {
331 retval = -EBUSY;
332 goto error_mutex_locked;
333 }
334 }
335 } else {
336 retval = open_wait(sdp, flags);
337 if (retval) /* -ERESTARTSYS or -ENODEV */
338 goto error_mutex_locked;
339 }
340
341 /* N.B. at this point we are holding the open_rel_lock */
342 if (flags & O_EXCL)
343 sdp->exclude = true;
344
345 if (sdp->open_cnt < 1) { /* no existing opens */
346 sdp->sgdebug = 0;
347 q = sdp->device->request_queue;
348 sdp->sg_tablesize = queue_max_segments(q);
349 }
350 sfp = sg_add_sfp(sdp);
351 if (IS_ERR(sfp)) {
352 retval = PTR_ERR(sfp);
353 goto out_undo;
354 }
355
356 filp->private_data = sfp;
357 sdp->open_cnt++;
358 mutex_unlock(&sdp->open_rel_lock);
359
360 retval = 0;
361sg_put:
362 kref_put(&sdp->d_ref, sg_device_destroy);
363 return retval;
364
365out_undo:
366 if (flags & O_EXCL) {
367 sdp->exclude = false; /* undo if error */
368 wake_up_interruptible(&sdp->open_wait);
369 }
370error_mutex_locked:
371 mutex_unlock(&sdp->open_rel_lock);
372error_out:
373 scsi_autopm_put_device(sdp->device);
374sdp_put:
375 scsi_device_put(sdp->device);
376 goto sg_put;
377}
378
379/* Release resources associated with a successful sg_open()
380 * Returns 0 on success, else a negated errno value */
381static int
382sg_release(struct inode *inode, struct file *filp)
383{
384 Sg_device *sdp;
385 Sg_fd *sfp;
386
387 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
388 return -ENXIO;
389 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
390
391 mutex_lock(&sdp->open_rel_lock);
392 scsi_autopm_put_device(sdp->device);
393 kref_put(&sfp->f_ref, sg_remove_sfp);
394 sdp->open_cnt--;
395
396 /* possibly many open()s waiting on exlude clearing, start many;
397 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
398 if (sdp->exclude) {
399 sdp->exclude = false;
400 wake_up_interruptible_all(&sdp->open_wait);
401 } else if (0 == sdp->open_cnt) {
402 wake_up_interruptible(&sdp->open_wait);
403 }
404 mutex_unlock(&sdp->open_rel_lock);
405 return 0;
406}
407
408static int get_sg_io_pack_id(int *pack_id, void __user *buf, size_t count)
409{
410 struct sg_header __user *old_hdr = buf;
411 int reply_len;
412
413 if (count >= SZ_SG_HEADER) {
414 /* negative reply_len means v3 format, otherwise v1/v2 */
415 if (get_user(reply_len, &old_hdr->reply_len))
416 return -EFAULT;
417
418 if (reply_len >= 0)
419 return get_user(*pack_id, &old_hdr->pack_id);
420
421 if (in_compat_syscall() &&
422 count >= sizeof(struct compat_sg_io_hdr)) {
423 struct compat_sg_io_hdr __user *hp = buf;
424
425 return get_user(*pack_id, &hp->pack_id);
426 }
427
428 if (count >= sizeof(struct sg_io_hdr)) {
429 struct sg_io_hdr __user *hp = buf;
430
431 return get_user(*pack_id, &hp->pack_id);
432 }
433 }
434
435 /* no valid header was passed, so ignore the pack_id */
436 *pack_id = -1;
437 return 0;
438}
439
440static ssize_t
441sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
442{
443 Sg_device *sdp;
444 Sg_fd *sfp;
445 Sg_request *srp;
446 int req_pack_id = -1;
447 sg_io_hdr_t *hp;
448 struct sg_header *old_hdr;
449 int retval;
450
451 /*
452 * This could cause a response to be stranded. Close the associated
453 * file descriptor to free up any resources being held.
454 */
455 retval = sg_check_file_access(filp, __func__);
456 if (retval)
457 return retval;
458
459 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
460 return -ENXIO;
461 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
462 "sg_read: count=%d\n", (int) count));
463
464 if (sfp->force_packid)
465 retval = get_sg_io_pack_id(&req_pack_id, buf, count);
466 if (retval)
467 return retval;
468
469 srp = sg_get_rq_mark(sfp, req_pack_id);
470 if (!srp) { /* now wait on packet to arrive */
471 if (atomic_read(&sdp->detaching))
472 return -ENODEV;
473 if (filp->f_flags & O_NONBLOCK)
474 return -EAGAIN;
475 retval = wait_event_interruptible(sfp->read_wait,
476 (atomic_read(&sdp->detaching) ||
477 (srp = sg_get_rq_mark(sfp, req_pack_id))));
478 if (atomic_read(&sdp->detaching))
479 return -ENODEV;
480 if (retval)
481 /* -ERESTARTSYS as signal hit process */
482 return retval;
483 }
484 if (srp->header.interface_id != '\0')
485 return sg_new_read(sfp, buf, count, srp);
486
487 hp = &srp->header;
488 old_hdr = kzalloc(SZ_SG_HEADER, GFP_KERNEL);
489 if (!old_hdr)
490 return -ENOMEM;
491
492 old_hdr->reply_len = (int) hp->timeout;
493 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
494 old_hdr->pack_id = hp->pack_id;
495 old_hdr->twelve_byte =
496 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
497 old_hdr->target_status = hp->masked_status;
498 old_hdr->host_status = hp->host_status;
499 old_hdr->driver_status = hp->driver_status;
500 if ((CHECK_CONDITION & hp->masked_status) ||
501 (DRIVER_SENSE & hp->driver_status))
502 memcpy(old_hdr->sense_buffer, srp->sense_b,
503 sizeof (old_hdr->sense_buffer));
504 switch (hp->host_status) {
505 /* This setup of 'result' is for backward compatibility and is best
506 ignored by the user who should use target, host + driver status */
507 case DID_OK:
508 case DID_PASSTHROUGH:
509 case DID_SOFT_ERROR:
510 old_hdr->result = 0;
511 break;
512 case DID_NO_CONNECT:
513 case DID_BUS_BUSY:
514 case DID_TIME_OUT:
515 old_hdr->result = EBUSY;
516 break;
517 case DID_BAD_TARGET:
518 case DID_ABORT:
519 case DID_PARITY:
520 case DID_RESET:
521 case DID_BAD_INTR:
522 old_hdr->result = EIO;
523 break;
524 case DID_ERROR:
525 old_hdr->result = (srp->sense_b[0] == 0 &&
526 hp->masked_status == GOOD) ? 0 : EIO;
527 break;
528 default:
529 old_hdr->result = EIO;
530 break;
531 }
532
533 /* Now copy the result back to the user buffer. */
534 if (count >= SZ_SG_HEADER) {
535 if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
536 retval = -EFAULT;
537 goto free_old_hdr;
538 }
539 buf += SZ_SG_HEADER;
540 if (count > old_hdr->reply_len)
541 count = old_hdr->reply_len;
542 if (count > SZ_SG_HEADER) {
543 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
544 retval = -EFAULT;
545 goto free_old_hdr;
546 }
547 }
548 } else
549 count = (old_hdr->result == 0) ? 0 : -EIO;
550 sg_finish_rem_req(srp);
551 sg_remove_request(sfp, srp);
552 retval = count;
553free_old_hdr:
554 kfree(old_hdr);
555 return retval;
556}
557
558static ssize_t
559sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
560{
561 sg_io_hdr_t *hp = &srp->header;
562 int err = 0, err2;
563 int len;
564
565 if (in_compat_syscall()) {
566 if (count < sizeof(struct compat_sg_io_hdr)) {
567 err = -EINVAL;
568 goto err_out;
569 }
570 } else if (count < SZ_SG_IO_HDR) {
571 err = -EINVAL;
572 goto err_out;
573 }
574 hp->sb_len_wr = 0;
575 if ((hp->mx_sb_len > 0) && hp->sbp) {
576 if ((CHECK_CONDITION & hp->masked_status) ||
577 (DRIVER_SENSE & hp->driver_status)) {
578 int sb_len = SCSI_SENSE_BUFFERSIZE;
579 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
580 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
581 len = (len > sb_len) ? sb_len : len;
582 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
583 err = -EFAULT;
584 goto err_out;
585 }
586 hp->sb_len_wr = len;
587 }
588 }
589 if (hp->masked_status || hp->host_status || hp->driver_status)
590 hp->info |= SG_INFO_CHECK;
591 err = put_sg_io_hdr(hp, buf);
592err_out:
593 err2 = sg_finish_rem_req(srp);
594 sg_remove_request(sfp, srp);
595 return err ? : err2 ? : count;
596}
597
598static ssize_t
599sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
600{
601 int mxsize, cmd_size, k;
602 int input_size, blocking;
603 unsigned char opcode;
604 Sg_device *sdp;
605 Sg_fd *sfp;
606 Sg_request *srp;
607 struct sg_header old_hdr;
608 sg_io_hdr_t *hp;
609 unsigned char cmnd[SG_MAX_CDB_SIZE];
610 int retval;
611
612 retval = sg_check_file_access(filp, __func__);
613 if (retval)
614 return retval;
615
616 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
617 return -ENXIO;
618 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
619 "sg_write: count=%d\n", (int) count));
620 if (atomic_read(&sdp->detaching))
621 return -ENODEV;
622 if (!((filp->f_flags & O_NONBLOCK) ||
623 scsi_block_when_processing_errors(sdp->device)))
624 return -ENXIO;
625
626 if (count < SZ_SG_HEADER)
627 return -EIO;
628 if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
629 return -EFAULT;
630 blocking = !(filp->f_flags & O_NONBLOCK);
631 if (old_hdr.reply_len < 0)
632 return sg_new_write(sfp, filp, buf, count,
633 blocking, 0, 0, NULL);
634 if (count < (SZ_SG_HEADER + 6))
635 return -EIO; /* The minimum scsi command length is 6 bytes. */
636
637 buf += SZ_SG_HEADER;
638 if (get_user(opcode, buf))
639 return -EFAULT;
640
641 if (!(srp = sg_add_request(sfp))) {
642 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
643 "sg_write: queue full\n"));
644 return -EDOM;
645 }
646 mutex_lock(&sfp->f_mutex);
647 if (sfp->next_cmd_len > 0) {
648 cmd_size = sfp->next_cmd_len;
649 sfp->next_cmd_len = 0; /* reset so only this write() effected */
650 } else {
651 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
652 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
653 cmd_size = 12;
654 }
655 mutex_unlock(&sfp->f_mutex);
656 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
657 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
658/* Determine buffer size. */
659 input_size = count - cmd_size;
660 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
661 mxsize -= SZ_SG_HEADER;
662 input_size -= SZ_SG_HEADER;
663 if (input_size < 0) {
664 sg_remove_request(sfp, srp);
665 return -EIO; /* User did not pass enough bytes for this command. */
666 }
667 hp = &srp->header;
668 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
669 hp->cmd_len = (unsigned char) cmd_size;
670 hp->iovec_count = 0;
671 hp->mx_sb_len = 0;
672 if (input_size > 0)
673 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
674 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
675 else
676 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
677 hp->dxfer_len = mxsize;
678 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
679 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
680 hp->dxferp = (char __user *)buf + cmd_size;
681 else
682 hp->dxferp = NULL;
683 hp->sbp = NULL;
684 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
685 hp->flags = input_size; /* structure abuse ... */
686 hp->pack_id = old_hdr.pack_id;
687 hp->usr_ptr = NULL;
688 if (copy_from_user(cmnd, buf, cmd_size)) {
689 sg_remove_request(sfp, srp);
690 return -EFAULT;
691 }
692 /*
693 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
694 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
695 * is a non-zero input_size, so emit a warning.
696 */
697 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
698 printk_ratelimited(KERN_WARNING
699 "sg_write: data in/out %d/%d bytes "
700 "for SCSI command 0x%x-- guessing "
701 "data in;\n program %s not setting "
702 "count and/or reply_len properly\n",
703 old_hdr.reply_len - (int)SZ_SG_HEADER,
704 input_size, (unsigned int) cmnd[0],
705 current->comm);
706 }
707 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
708 return (k < 0) ? k : count;
709}
710
711static ssize_t
712sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
713 size_t count, int blocking, int read_only, int sg_io_owned,
714 Sg_request **o_srp)
715{
716 int k;
717 Sg_request *srp;
718 sg_io_hdr_t *hp;
719 unsigned char cmnd[SG_MAX_CDB_SIZE];
720 int timeout;
721 unsigned long ul_timeout;
722
723 if (count < SZ_SG_IO_HDR)
724 return -EINVAL;
725
726 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
727 if (!(srp = sg_add_request(sfp))) {
728 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
729 "sg_new_write: queue full\n"));
730 return -EDOM;
731 }
732 srp->sg_io_owned = sg_io_owned;
733 hp = &srp->header;
734 if (get_sg_io_hdr(hp, buf)) {
735 sg_remove_request(sfp, srp);
736 return -EFAULT;
737 }
738 if (hp->interface_id != 'S') {
739 sg_remove_request(sfp, srp);
740 return -ENOSYS;
741 }
742 if (hp->flags & SG_FLAG_MMAP_IO) {
743 if (hp->dxfer_len > sfp->reserve.bufflen) {
744 sg_remove_request(sfp, srp);
745 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
746 }
747 if (hp->flags & SG_FLAG_DIRECT_IO) {
748 sg_remove_request(sfp, srp);
749 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
750 }
751 if (sfp->res_in_use) {
752 sg_remove_request(sfp, srp);
753 return -EBUSY; /* reserve buffer already being used */
754 }
755 }
756 ul_timeout = msecs_to_jiffies(srp->header.timeout);
757 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
758 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
759 sg_remove_request(sfp, srp);
760 return -EMSGSIZE;
761 }
762 if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
763 sg_remove_request(sfp, srp);
764 return -EFAULT;
765 }
766 if (read_only && sg_allow_access(file, cmnd)) {
767 sg_remove_request(sfp, srp);
768 return -EPERM;
769 }
770 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
771 if (k < 0)
772 return k;
773 if (o_srp)
774 *o_srp = srp;
775 return count;
776}
777
778static int
779sg_common_write(Sg_fd * sfp, Sg_request * srp,
780 unsigned char *cmnd, int timeout, int blocking)
781{
782 int k, at_head;
783 Sg_device *sdp = sfp->parentdp;
784 sg_io_hdr_t *hp = &srp->header;
785
786 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
787 hp->status = 0;
788 hp->masked_status = 0;
789 hp->msg_status = 0;
790 hp->info = 0;
791 hp->host_status = 0;
792 hp->driver_status = 0;
793 hp->resid = 0;
794 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
795 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
796 (int) cmnd[0], (int) hp->cmd_len));
797
798 if (hp->dxfer_len >= SZ_256M) {
799 sg_remove_request(sfp, srp);
800 return -EINVAL;
801 }
802
803 k = sg_start_req(srp, cmnd);
804 if (k) {
805 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
806 "sg_common_write: start_req err=%d\n", k));
807 sg_finish_rem_req(srp);
808 sg_remove_request(sfp, srp);
809 return k; /* probably out of space --> ENOMEM */
810 }
811 if (atomic_read(&sdp->detaching)) {
812 if (srp->bio) {
813 scsi_req_free_cmd(scsi_req(srp->rq));
814 blk_put_request(srp->rq);
815 srp->rq = NULL;
816 }
817
818 sg_finish_rem_req(srp);
819 sg_remove_request(sfp, srp);
820 return -ENODEV;
821 }
822
823 hp->duration = jiffies_to_msecs(jiffies);
824 if (hp->interface_id != '\0' && /* v3 (or later) interface */
825 (SG_FLAG_Q_AT_TAIL & hp->flags))
826 at_head = 0;
827 else
828 at_head = 1;
829
830 srp->rq->timeout = timeout;
831 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
832 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
833 srp->rq, at_head, sg_rq_end_io);
834 return 0;
835}
836
837static int srp_done(Sg_fd *sfp, Sg_request *srp)
838{
839 unsigned long flags;
840 int ret;
841
842 read_lock_irqsave(&sfp->rq_list_lock, flags);
843 ret = srp->done;
844 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
845 return ret;
846}
847
848static int max_sectors_bytes(struct request_queue *q)
849{
850 unsigned int max_sectors = queue_max_sectors(q);
851
852 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
853
854 return max_sectors << 9;
855}
856
857static void
858sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
859{
860 Sg_request *srp;
861 int val;
862 unsigned int ms;
863
864 val = 0;
865 list_for_each_entry(srp, &sfp->rq_list, entry) {
866 if (val >= SG_MAX_QUEUE)
867 break;
868 rinfo[val].req_state = srp->done + 1;
869 rinfo[val].problem =
870 srp->header.masked_status &
871 srp->header.host_status &
872 srp->header.driver_status;
873 if (srp->done)
874 rinfo[val].duration =
875 srp->header.duration;
876 else {
877 ms = jiffies_to_msecs(jiffies);
878 rinfo[val].duration =
879 (ms > srp->header.duration) ?
880 (ms - srp->header.duration) : 0;
881 }
882 rinfo[val].orphan = srp->orphan;
883 rinfo[val].sg_io_owned = srp->sg_io_owned;
884 rinfo[val].pack_id = srp->header.pack_id;
885 rinfo[val].usr_ptr = srp->header.usr_ptr;
886 val++;
887 }
888}
889
890#ifdef CONFIG_COMPAT
891struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */
892 char req_state;
893 char orphan;
894 char sg_io_owned;
895 char problem;
896 int pack_id;
897 compat_uptr_t usr_ptr;
898 unsigned int duration;
899 int unused;
900};
901
902static int put_compat_request_table(struct compat_sg_req_info __user *o,
903 struct sg_req_info *rinfo)
904{
905 int i;
906 for (i = 0; i < SG_MAX_QUEUE; i++) {
907 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) ||
908 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) ||
909 put_user(rinfo[i].duration, &o[i].duration) ||
910 put_user(rinfo[i].unused, &o[i].unused))
911 return -EFAULT;
912 }
913 return 0;
914}
915#endif
916
917static long
918sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp,
919 unsigned int cmd_in, void __user *p)
920{
921 int __user *ip = p;
922 int result, val, read_only;
923 Sg_request *srp;
924 unsigned long iflags;
925
926 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
927 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
928 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
929
930 switch (cmd_in) {
931 case SG_IO:
932 if (atomic_read(&sdp->detaching))
933 return -ENODEV;
934 if (!scsi_block_when_processing_errors(sdp->device))
935 return -ENXIO;
936 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
937 1, read_only, 1, &srp);
938 if (result < 0)
939 return result;
940 result = wait_event_interruptible(sfp->read_wait,
941 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
942 if (atomic_read(&sdp->detaching))
943 return -ENODEV;
944 write_lock_irq(&sfp->rq_list_lock);
945 if (srp->done) {
946 srp->done = 2;
947 write_unlock_irq(&sfp->rq_list_lock);
948 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
949 return (result < 0) ? result : 0;
950 }
951 srp->orphan = 1;
952 write_unlock_irq(&sfp->rq_list_lock);
953 return result; /* -ERESTARTSYS because signal hit process */
954 case SG_SET_TIMEOUT:
955 result = get_user(val, ip);
956 if (result)
957 return result;
958 if (val < 0)
959 return -EIO;
960 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
961 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
962 INT_MAX);
963 sfp->timeout_user = val;
964 sfp->timeout = mult_frac(val, HZ, USER_HZ);
965
966 return 0;
967 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
968 /* strange ..., for backward compatibility */
969 return sfp->timeout_user;
970 case SG_SET_FORCE_LOW_DMA:
971 /*
972 * N.B. This ioctl never worked properly, but failed to
973 * return an error value. So returning '0' to keep compability
974 * with legacy applications.
975 */
976 return 0;
977 case SG_GET_LOW_DMA:
978 return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
979 case SG_GET_SCSI_ID:
980 {
981 sg_scsi_id_t v;
982
983 if (atomic_read(&sdp->detaching))
984 return -ENODEV;
985 memset(&v, 0, sizeof(v));
986 v.host_no = sdp->device->host->host_no;
987 v.channel = sdp->device->channel;
988 v.scsi_id = sdp->device->id;
989 v.lun = sdp->device->lun;
990 v.scsi_type = sdp->device->type;
991 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun;
992 v.d_queue_depth = sdp->device->queue_depth;
993 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t)))
994 return -EFAULT;
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 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1005 list_for_each_entry(srp, &sfp->rq_list, entry) {
1006 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1007 read_unlock_irqrestore(&sfp->rq_list_lock,
1008 iflags);
1009 return put_user(srp->header.pack_id, ip);
1010 }
1011 }
1012 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1013 return put_user(-1, ip);
1014 case SG_GET_NUM_WAITING:
1015 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1016 val = 0;
1017 list_for_each_entry(srp, &sfp->rq_list, entry) {
1018 if ((1 == srp->done) && (!srp->sg_io_owned))
1019 ++val;
1020 }
1021 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1022 return put_user(val, ip);
1023 case SG_GET_SG_TABLESIZE:
1024 return put_user(sdp->sg_tablesize, ip);
1025 case SG_SET_RESERVED_SIZE:
1026 result = get_user(val, ip);
1027 if (result)
1028 return result;
1029 if (val < 0)
1030 return -EINVAL;
1031 val = min_t(int, val,
1032 max_sectors_bytes(sdp->device->request_queue));
1033 mutex_lock(&sfp->f_mutex);
1034 if (val != sfp->reserve.bufflen) {
1035 if (sfp->mmap_called ||
1036 sfp->res_in_use) {
1037 mutex_unlock(&sfp->f_mutex);
1038 return -EBUSY;
1039 }
1040
1041 sg_remove_scat(sfp, &sfp->reserve);
1042 sg_build_reserve(sfp, val);
1043 }
1044 mutex_unlock(&sfp->f_mutex);
1045 return 0;
1046 case SG_GET_RESERVED_SIZE:
1047 val = min_t(int, sfp->reserve.bufflen,
1048 max_sectors_bytes(sdp->device->request_queue));
1049 return put_user(val, ip);
1050 case SG_SET_COMMAND_Q:
1051 result = get_user(val, ip);
1052 if (result)
1053 return result;
1054 sfp->cmd_q = val ? 1 : 0;
1055 return 0;
1056 case SG_GET_COMMAND_Q:
1057 return put_user((int) sfp->cmd_q, ip);
1058 case SG_SET_KEEP_ORPHAN:
1059 result = get_user(val, ip);
1060 if (result)
1061 return result;
1062 sfp->keep_orphan = val;
1063 return 0;
1064 case SG_GET_KEEP_ORPHAN:
1065 return put_user((int) sfp->keep_orphan, ip);
1066 case SG_NEXT_CMD_LEN:
1067 result = get_user(val, ip);
1068 if (result)
1069 return result;
1070 if (val > SG_MAX_CDB_SIZE)
1071 return -ENOMEM;
1072 sfp->next_cmd_len = (val > 0) ? val : 0;
1073 return 0;
1074 case SG_GET_VERSION_NUM:
1075 return put_user(sg_version_num, ip);
1076 case SG_GET_ACCESS_COUNT:
1077 /* faked - we don't have a real access count anymore */
1078 val = (sdp->device ? 1 : 0);
1079 return put_user(val, ip);
1080 case SG_GET_REQUEST_TABLE:
1081 {
1082 sg_req_info_t *rinfo;
1083
1084 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,
1085 GFP_KERNEL);
1086 if (!rinfo)
1087 return -ENOMEM;
1088 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1089 sg_fill_request_table(sfp, rinfo);
1090 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1091 #ifdef CONFIG_COMPAT
1092 if (in_compat_syscall())
1093 result = put_compat_request_table(p, rinfo);
1094 else
1095 #endif
1096 result = copy_to_user(p, rinfo,
1097 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1098 result = result ? -EFAULT : 0;
1099 kfree(rinfo);
1100 return result;
1101 }
1102 case SG_EMULATED_HOST:
1103 if (atomic_read(&sdp->detaching))
1104 return -ENODEV;
1105 return put_user(sdp->device->host->hostt->emulated, ip);
1106 case SCSI_IOCTL_SEND_COMMAND:
1107 if (atomic_read(&sdp->detaching))
1108 return -ENODEV;
1109 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1110 case SG_SET_DEBUG:
1111 result = get_user(val, ip);
1112 if (result)
1113 return result;
1114 sdp->sgdebug = (char) val;
1115 return 0;
1116 case BLKSECTGET:
1117 return put_user(max_sectors_bytes(sdp->device->request_queue),
1118 ip);
1119 case BLKTRACESETUP:
1120 return blk_trace_setup(sdp->device->request_queue,
1121 sdp->disk->disk_name,
1122 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1123 NULL, p);
1124 case BLKTRACESTART:
1125 return blk_trace_startstop(sdp->device->request_queue, 1);
1126 case BLKTRACESTOP:
1127 return blk_trace_startstop(sdp->device->request_queue, 0);
1128 case BLKTRACETEARDOWN:
1129 return blk_trace_remove(sdp->device->request_queue);
1130 case SCSI_IOCTL_GET_IDLUN:
1131 case SCSI_IOCTL_GET_BUS_NUMBER:
1132 case SCSI_IOCTL_PROBE_HOST:
1133 case SG_GET_TRANSFORM:
1134 case SG_SCSI_RESET:
1135 if (atomic_read(&sdp->detaching))
1136 return -ENODEV;
1137 break;
1138 default:
1139 if (read_only)
1140 return -EPERM; /* don't know so take safe approach */
1141 break;
1142 }
1143
1144 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1145 cmd_in, filp->f_flags & O_NDELAY);
1146 if (result)
1147 return result;
1148
1149 return -ENOIOCTLCMD;
1150}
1151
1152static long
1153sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1154{
1155 void __user *p = (void __user *)arg;
1156 Sg_device *sdp;
1157 Sg_fd *sfp;
1158 int ret;
1159
1160 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1161 return -ENXIO;
1162
1163 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
1164 if (ret != -ENOIOCTLCMD)
1165 return ret;
1166
1167 return scsi_ioctl(sdp->device, cmd_in, p);
1168}
1169
1170#ifdef CONFIG_COMPAT
1171static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1172{
1173 void __user *p = compat_ptr(arg);
1174 Sg_device *sdp;
1175 Sg_fd *sfp;
1176 int ret;
1177
1178 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1179 return -ENXIO;
1180
1181 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
1182 if (ret != -ENOIOCTLCMD)
1183 return ret;
1184
1185 return scsi_compat_ioctl(sdp->device, cmd_in, p);
1186}
1187#endif
1188
1189static __poll_t
1190sg_poll(struct file *filp, poll_table * wait)
1191{
1192 __poll_t res = 0;
1193 Sg_device *sdp;
1194 Sg_fd *sfp;
1195 Sg_request *srp;
1196 int count = 0;
1197 unsigned long iflags;
1198
1199 sfp = filp->private_data;
1200 if (!sfp)
1201 return EPOLLERR;
1202 sdp = sfp->parentdp;
1203 if (!sdp)
1204 return EPOLLERR;
1205 poll_wait(filp, &sfp->read_wait, wait);
1206 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1207 list_for_each_entry(srp, &sfp->rq_list, entry) {
1208 /* if any read waiting, flag it */
1209 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1210 res = EPOLLIN | EPOLLRDNORM;
1211 ++count;
1212 }
1213 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1214
1215 if (atomic_read(&sdp->detaching))
1216 res |= EPOLLHUP;
1217 else if (!sfp->cmd_q) {
1218 if (0 == count)
1219 res |= EPOLLOUT | EPOLLWRNORM;
1220 } else if (count < SG_MAX_QUEUE)
1221 res |= EPOLLOUT | EPOLLWRNORM;
1222 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1223 "sg_poll: res=0x%x\n", (__force u32) res));
1224 return res;
1225}
1226
1227static int
1228sg_fasync(int fd, struct file *filp, int mode)
1229{
1230 Sg_device *sdp;
1231 Sg_fd *sfp;
1232
1233 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1234 return -ENXIO;
1235 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1236 "sg_fasync: mode=%d\n", mode));
1237
1238 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1239}
1240
1241static vm_fault_t
1242sg_vma_fault(struct vm_fault *vmf)
1243{
1244 struct vm_area_struct *vma = vmf->vma;
1245 Sg_fd *sfp;
1246 unsigned long offset, len, sa;
1247 Sg_scatter_hold *rsv_schp;
1248 int k, length;
1249
1250 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1251 return VM_FAULT_SIGBUS;
1252 rsv_schp = &sfp->reserve;
1253 offset = vmf->pgoff << PAGE_SHIFT;
1254 if (offset >= rsv_schp->bufflen)
1255 return VM_FAULT_SIGBUS;
1256 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1257 "sg_vma_fault: offset=%lu, scatg=%d\n",
1258 offset, rsv_schp->k_use_sg));
1259 sa = vma->vm_start;
1260 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1261 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1262 len = vma->vm_end - sa;
1263 len = (len < length) ? len : length;
1264 if (offset < len) {
1265 struct page *page = nth_page(rsv_schp->pages[k],
1266 offset >> PAGE_SHIFT);
1267 get_page(page); /* increment page count */
1268 vmf->page = page;
1269 return 0; /* success */
1270 }
1271 sa += len;
1272 offset -= len;
1273 }
1274
1275 return VM_FAULT_SIGBUS;
1276}
1277
1278static const struct vm_operations_struct sg_mmap_vm_ops = {
1279 .fault = sg_vma_fault,
1280};
1281
1282static int
1283sg_mmap(struct file *filp, struct vm_area_struct *vma)
1284{
1285 Sg_fd *sfp;
1286 unsigned long req_sz, len, sa;
1287 Sg_scatter_hold *rsv_schp;
1288 int k, length;
1289 int ret = 0;
1290
1291 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1292 return -ENXIO;
1293 req_sz = vma->vm_end - vma->vm_start;
1294 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1295 "sg_mmap starting, vm_start=%p, len=%d\n",
1296 (void *) vma->vm_start, (int) req_sz));
1297 if (vma->vm_pgoff)
1298 return -EINVAL; /* want no offset */
1299 rsv_schp = &sfp->reserve;
1300 mutex_lock(&sfp->f_mutex);
1301 if (req_sz > rsv_schp->bufflen) {
1302 ret = -ENOMEM; /* cannot map more than reserved buffer */
1303 goto out;
1304 }
1305
1306 sa = vma->vm_start;
1307 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1308 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1309 len = vma->vm_end - sa;
1310 len = (len < length) ? len : length;
1311 sa += len;
1312 }
1313
1314 sfp->mmap_called = 1;
1315 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1316 vma->vm_private_data = sfp;
1317 vma->vm_ops = &sg_mmap_vm_ops;
1318out:
1319 mutex_unlock(&sfp->f_mutex);
1320 return ret;
1321}
1322
1323static void
1324sg_rq_end_io_usercontext(struct work_struct *work)
1325{
1326 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1327 struct sg_fd *sfp = srp->parentfp;
1328
1329 sg_finish_rem_req(srp);
1330 sg_remove_request(sfp, srp);
1331 kref_put(&sfp->f_ref, sg_remove_sfp);
1332}
1333
1334/*
1335 * This function is a "bottom half" handler that is called by the mid
1336 * level when a command is completed (or has failed).
1337 */
1338static void
1339sg_rq_end_io(struct request *rq, blk_status_t status)
1340{
1341 struct sg_request *srp = rq->end_io_data;
1342 struct scsi_request *req = scsi_req(rq);
1343 Sg_device *sdp;
1344 Sg_fd *sfp;
1345 unsigned long iflags;
1346 unsigned int ms;
1347 char *sense;
1348 int result, resid, done = 1;
1349
1350 if (WARN_ON(srp->done != 0))
1351 return;
1352
1353 sfp = srp->parentfp;
1354 if (WARN_ON(sfp == NULL))
1355 return;
1356
1357 sdp = sfp->parentdp;
1358 if (unlikely(atomic_read(&sdp->detaching)))
1359 pr_info("%s: device detaching\n", __func__);
1360
1361 sense = req->sense;
1362 result = req->result;
1363 resid = req->resid_len;
1364
1365 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1366 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1367 srp->header.pack_id, result));
1368 srp->header.resid = resid;
1369 ms = jiffies_to_msecs(jiffies);
1370 srp->header.duration = (ms > srp->header.duration) ?
1371 (ms - srp->header.duration) : 0;
1372 if (0 != result) {
1373 struct scsi_sense_hdr sshdr;
1374
1375 srp->header.status = 0xff & result;
1376 srp->header.masked_status = status_byte(result);
1377 srp->header.msg_status = msg_byte(result);
1378 srp->header.host_status = host_byte(result);
1379 srp->header.driver_status = driver_byte(result);
1380 if ((sdp->sgdebug > 0) &&
1381 ((CHECK_CONDITION == srp->header.masked_status) ||
1382 (COMMAND_TERMINATED == srp->header.masked_status)))
1383 __scsi_print_sense(sdp->device, __func__, sense,
1384 SCSI_SENSE_BUFFERSIZE);
1385
1386 /* Following if statement is a patch supplied by Eric Youngdale */
1387 if (driver_byte(result) != 0
1388 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1389 && !scsi_sense_is_deferred(&sshdr)
1390 && sshdr.sense_key == UNIT_ATTENTION
1391 && sdp->device->removable) {
1392 /* Detected possible disc change. Set the bit - this */
1393 /* may be used if there are filesystems using this device */
1394 sdp->device->changed = 1;
1395 }
1396 }
1397
1398 if (req->sense_len)
1399 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1400
1401 /* Rely on write phase to clean out srp status values, so no "else" */
1402
1403 /*
1404 * Free the request as soon as it is complete so that its resources
1405 * can be reused without waiting for userspace to read() the
1406 * result. But keep the associated bio (if any) around until
1407 * blk_rq_unmap_user() can be called from user context.
1408 */
1409 srp->rq = NULL;
1410 scsi_req_free_cmd(scsi_req(rq));
1411 blk_put_request(rq);
1412
1413 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1414 if (unlikely(srp->orphan)) {
1415 if (sfp->keep_orphan)
1416 srp->sg_io_owned = 0;
1417 else
1418 done = 0;
1419 }
1420 srp->done = done;
1421 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1422
1423 if (likely(done)) {
1424 /* Now wake up any sg_read() that is waiting for this
1425 * packet.
1426 */
1427 wake_up_interruptible(&sfp->read_wait);
1428 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1429 kref_put(&sfp->f_ref, sg_remove_sfp);
1430 } else {
1431 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1432 schedule_work(&srp->ew.work);
1433 }
1434}
1435
1436static const struct file_operations sg_fops = {
1437 .owner = THIS_MODULE,
1438 .read = sg_read,
1439 .write = sg_write,
1440 .poll = sg_poll,
1441 .unlocked_ioctl = sg_ioctl,
1442#ifdef CONFIG_COMPAT
1443 .compat_ioctl = sg_compat_ioctl,
1444#endif
1445 .open = sg_open,
1446 .mmap = sg_mmap,
1447 .release = sg_release,
1448 .fasync = sg_fasync,
1449 .llseek = no_llseek,
1450};
1451
1452static struct class *sg_sysfs_class;
1453
1454static int sg_sysfs_valid = 0;
1455
1456static Sg_device *
1457sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1458{
1459 struct request_queue *q = scsidp->request_queue;
1460 Sg_device *sdp;
1461 unsigned long iflags;
1462 int error;
1463 u32 k;
1464
1465 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1466 if (!sdp) {
1467 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1468 "failure\n", __func__);
1469 return ERR_PTR(-ENOMEM);
1470 }
1471
1472 idr_preload(GFP_KERNEL);
1473 write_lock_irqsave(&sg_index_lock, iflags);
1474
1475 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1476 if (error < 0) {
1477 if (error == -ENOSPC) {
1478 sdev_printk(KERN_WARNING, scsidp,
1479 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1480 scsidp->type, SG_MAX_DEVS - 1);
1481 error = -ENODEV;
1482 } else {
1483 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1484 "allocation Sg_device failure: %d\n",
1485 __func__, error);
1486 }
1487 goto out_unlock;
1488 }
1489 k = error;
1490
1491 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1492 "sg_alloc: dev=%d \n", k));
1493 sprintf(disk->disk_name, "sg%d", k);
1494 disk->first_minor = k;
1495 sdp->disk = disk;
1496 sdp->device = scsidp;
1497 mutex_init(&sdp->open_rel_lock);
1498 INIT_LIST_HEAD(&sdp->sfds);
1499 init_waitqueue_head(&sdp->open_wait);
1500 atomic_set(&sdp->detaching, 0);
1501 rwlock_init(&sdp->sfd_lock);
1502 sdp->sg_tablesize = queue_max_segments(q);
1503 sdp->index = k;
1504 kref_init(&sdp->d_ref);
1505 error = 0;
1506
1507out_unlock:
1508 write_unlock_irqrestore(&sg_index_lock, iflags);
1509 idr_preload_end();
1510
1511 if (error) {
1512 kfree(sdp);
1513 return ERR_PTR(error);
1514 }
1515 return sdp;
1516}
1517
1518static int
1519sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1520{
1521 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1522 struct gendisk *disk;
1523 Sg_device *sdp = NULL;
1524 struct cdev * cdev = NULL;
1525 int error;
1526 unsigned long iflags;
1527
1528 disk = alloc_disk(1);
1529 if (!disk) {
1530 pr_warn("%s: alloc_disk failed\n", __func__);
1531 return -ENOMEM;
1532 }
1533 disk->major = SCSI_GENERIC_MAJOR;
1534
1535 error = -ENOMEM;
1536 cdev = cdev_alloc();
1537 if (!cdev) {
1538 pr_warn("%s: cdev_alloc failed\n", __func__);
1539 goto out;
1540 }
1541 cdev->owner = THIS_MODULE;
1542 cdev->ops = &sg_fops;
1543
1544 sdp = sg_alloc(disk, scsidp);
1545 if (IS_ERR(sdp)) {
1546 pr_warn("%s: sg_alloc failed\n", __func__);
1547 error = PTR_ERR(sdp);
1548 goto out;
1549 }
1550
1551 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1552 if (error)
1553 goto cdev_add_err;
1554
1555 sdp->cdev = cdev;
1556 if (sg_sysfs_valid) {
1557 struct device *sg_class_member;
1558
1559 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1560 MKDEV(SCSI_GENERIC_MAJOR,
1561 sdp->index),
1562 sdp, "%s", disk->disk_name);
1563 if (IS_ERR(sg_class_member)) {
1564 pr_err("%s: device_create failed\n", __func__);
1565 error = PTR_ERR(sg_class_member);
1566 goto cdev_add_err;
1567 }
1568 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1569 &sg_class_member->kobj, "generic");
1570 if (error)
1571 pr_err("%s: unable to make symlink 'generic' back "
1572 "to sg%d\n", __func__, sdp->index);
1573 } else
1574 pr_warn("%s: sg_sys Invalid\n", __func__);
1575
1576 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1577 "type %d\n", sdp->index, scsidp->type);
1578
1579 dev_set_drvdata(cl_dev, sdp);
1580
1581 return 0;
1582
1583cdev_add_err:
1584 write_lock_irqsave(&sg_index_lock, iflags);
1585 idr_remove(&sg_index_idr, sdp->index);
1586 write_unlock_irqrestore(&sg_index_lock, iflags);
1587 kfree(sdp);
1588
1589out:
1590 put_disk(disk);
1591 if (cdev)
1592 cdev_del(cdev);
1593 return error;
1594}
1595
1596static void
1597sg_device_destroy(struct kref *kref)
1598{
1599 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1600 unsigned long flags;
1601
1602 /* CAUTION! Note that the device can still be found via idr_find()
1603 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1604 * any other cleanup.
1605 */
1606
1607 write_lock_irqsave(&sg_index_lock, flags);
1608 idr_remove(&sg_index_idr, sdp->index);
1609 write_unlock_irqrestore(&sg_index_lock, flags);
1610
1611 SCSI_LOG_TIMEOUT(3,
1612 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1613
1614 put_disk(sdp->disk);
1615 kfree(sdp);
1616}
1617
1618static void
1619sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1620{
1621 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1622 Sg_device *sdp = dev_get_drvdata(cl_dev);
1623 unsigned long iflags;
1624 Sg_fd *sfp;
1625 int val;
1626
1627 if (!sdp)
1628 return;
1629 /* want sdp->detaching non-zero as soon as possible */
1630 val = atomic_inc_return(&sdp->detaching);
1631 if (val > 1)
1632 return; /* only want to do following once per device */
1633
1634 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1635 "%s\n", __func__));
1636
1637 read_lock_irqsave(&sdp->sfd_lock, iflags);
1638 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1639 wake_up_interruptible_all(&sfp->read_wait);
1640 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1641 }
1642 wake_up_interruptible_all(&sdp->open_wait);
1643 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1644
1645 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1646 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1647 cdev_del(sdp->cdev);
1648 sdp->cdev = NULL;
1649
1650 kref_put(&sdp->d_ref, sg_device_destroy);
1651}
1652
1653module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1654module_param_named(def_reserved_size, def_reserved_size, int,
1655 S_IRUGO | S_IWUSR);
1656module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1657
1658MODULE_AUTHOR("Douglas Gilbert");
1659MODULE_DESCRIPTION("SCSI generic (sg) driver");
1660MODULE_LICENSE("GPL");
1661MODULE_VERSION(SG_VERSION_STR);
1662MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1663
1664MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1665 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1666MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1667MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1668
1669static int __init
1670init_sg(void)
1671{
1672 int rc;
1673
1674 if (scatter_elem_sz < PAGE_SIZE) {
1675 scatter_elem_sz = PAGE_SIZE;
1676 scatter_elem_sz_prev = scatter_elem_sz;
1677 }
1678 if (def_reserved_size >= 0)
1679 sg_big_buff = def_reserved_size;
1680 else
1681 def_reserved_size = sg_big_buff;
1682
1683 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1684 SG_MAX_DEVS, "sg");
1685 if (rc)
1686 return rc;
1687 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1688 if ( IS_ERR(sg_sysfs_class) ) {
1689 rc = PTR_ERR(sg_sysfs_class);
1690 goto err_out;
1691 }
1692 sg_sysfs_valid = 1;
1693 rc = scsi_register_interface(&sg_interface);
1694 if (0 == rc) {
1695#ifdef CONFIG_SCSI_PROC_FS
1696 sg_proc_init();
1697#endif /* CONFIG_SCSI_PROC_FS */
1698 return 0;
1699 }
1700 class_destroy(sg_sysfs_class);
1701err_out:
1702 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1703 return rc;
1704}
1705
1706static void __exit
1707exit_sg(void)
1708{
1709#ifdef CONFIG_SCSI_PROC_FS
1710 remove_proc_subtree("scsi/sg", NULL);
1711#endif /* CONFIG_SCSI_PROC_FS */
1712 scsi_unregister_interface(&sg_interface);
1713 class_destroy(sg_sysfs_class);
1714 sg_sysfs_valid = 0;
1715 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1716 SG_MAX_DEVS);
1717 idr_destroy(&sg_index_idr);
1718}
1719
1720static int
1721sg_start_req(Sg_request *srp, unsigned char *cmd)
1722{
1723 int res;
1724 struct request *rq;
1725 struct scsi_request *req;
1726 Sg_fd *sfp = srp->parentfp;
1727 sg_io_hdr_t *hp = &srp->header;
1728 int dxfer_len = (int) hp->dxfer_len;
1729 int dxfer_dir = hp->dxfer_direction;
1730 unsigned int iov_count = hp->iovec_count;
1731 Sg_scatter_hold *req_schp = &srp->data;
1732 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1733 struct request_queue *q = sfp->parentdp->device->request_queue;
1734 struct rq_map_data *md, map_data;
1735 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1736 unsigned char *long_cmdp = NULL;
1737
1738 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1739 "sg_start_req: dxfer_len=%d\n",
1740 dxfer_len));
1741
1742 if (hp->cmd_len > BLK_MAX_CDB) {
1743 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1744 if (!long_cmdp)
1745 return -ENOMEM;
1746 }
1747
1748 /*
1749 * NOTE
1750 *
1751 * With scsi-mq enabled, there are a fixed number of preallocated
1752 * requests equal in number to shost->can_queue. If all of the
1753 * preallocated requests are already in use, then blk_get_request()
1754 * will sleep until an active command completes, freeing up a request.
1755 * Although waiting in an asynchronous interface is less than ideal, we
1756 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
1757 * not expect an EWOULDBLOCK from this condition.
1758 */
1759 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1760 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
1761 if (IS_ERR(rq)) {
1762 kfree(long_cmdp);
1763 return PTR_ERR(rq);
1764 }
1765 req = scsi_req(rq);
1766
1767 if (hp->cmd_len > BLK_MAX_CDB)
1768 req->cmd = long_cmdp;
1769 memcpy(req->cmd, cmd, hp->cmd_len);
1770 req->cmd_len = hp->cmd_len;
1771
1772 srp->rq = rq;
1773 rq->end_io_data = srp;
1774 req->retries = SG_DEFAULT_RETRIES;
1775
1776 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1777 return 0;
1778
1779 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1780 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1781 !sfp->parentdp->device->host->unchecked_isa_dma &&
1782 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1783 md = NULL;
1784 else
1785 md = &map_data;
1786
1787 if (md) {
1788 mutex_lock(&sfp->f_mutex);
1789 if (dxfer_len <= rsv_schp->bufflen &&
1790 !sfp->res_in_use) {
1791 sfp->res_in_use = 1;
1792 sg_link_reserve(sfp, srp, dxfer_len);
1793 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1794 res = -EBUSY; /* sfp->res_in_use == 1 */
1795 if (dxfer_len > rsv_schp->bufflen)
1796 res = -ENOMEM;
1797 mutex_unlock(&sfp->f_mutex);
1798 return res;
1799 } else {
1800 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1801 if (res) {
1802 mutex_unlock(&sfp->f_mutex);
1803 return res;
1804 }
1805 }
1806 mutex_unlock(&sfp->f_mutex);
1807
1808 md->pages = req_schp->pages;
1809 md->page_order = req_schp->page_order;
1810 md->nr_entries = req_schp->k_use_sg;
1811 md->offset = 0;
1812 md->null_mapped = hp->dxferp ? 0 : 1;
1813 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1814 md->from_user = 1;
1815 else
1816 md->from_user = 0;
1817 }
1818
1819 if (iov_count) {
1820 struct iovec *iov = NULL;
1821 struct iov_iter i;
1822
1823#ifdef CONFIG_COMPAT
1824 if (in_compat_syscall())
1825 res = compat_import_iovec(rw, hp->dxferp, iov_count,
1826 0, &iov, &i);
1827 else
1828#endif
1829 res = import_iovec(rw, hp->dxferp, iov_count,
1830 0, &iov, &i);
1831 if (res < 0)
1832 return res;
1833
1834 iov_iter_truncate(&i, hp->dxfer_len);
1835 if (!iov_iter_count(&i)) {
1836 kfree(iov);
1837 return -EINVAL;
1838 }
1839
1840 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1841 kfree(iov);
1842 } else
1843 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1844 hp->dxfer_len, GFP_ATOMIC);
1845
1846 if (!res) {
1847 srp->bio = rq->bio;
1848
1849 if (!md) {
1850 req_schp->dio_in_use = 1;
1851 hp->info |= SG_INFO_DIRECT_IO;
1852 }
1853 }
1854 return res;
1855}
1856
1857static int
1858sg_finish_rem_req(Sg_request *srp)
1859{
1860 int ret = 0;
1861
1862 Sg_fd *sfp = srp->parentfp;
1863 Sg_scatter_hold *req_schp = &srp->data;
1864
1865 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1866 "sg_finish_rem_req: res_used=%d\n",
1867 (int) srp->res_used));
1868 if (srp->bio)
1869 ret = blk_rq_unmap_user(srp->bio);
1870
1871 if (srp->rq) {
1872 scsi_req_free_cmd(scsi_req(srp->rq));
1873 blk_put_request(srp->rq);
1874 }
1875
1876 if (srp->res_used)
1877 sg_unlink_reserve(sfp, srp);
1878 else
1879 sg_remove_scat(sfp, req_schp);
1880
1881 return ret;
1882}
1883
1884static int
1885sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1886{
1887 int sg_bufflen = tablesize * sizeof(struct page *);
1888 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1889
1890 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1891 if (!schp->pages)
1892 return -ENOMEM;
1893 schp->sglist_len = sg_bufflen;
1894 return tablesize; /* number of scat_gath elements allocated */
1895}
1896
1897static int
1898sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1899{
1900 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1901 int sg_tablesize = sfp->parentdp->sg_tablesize;
1902 int blk_size = buff_size, order;
1903 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
1904 struct sg_device *sdp = sfp->parentdp;
1905
1906 if (blk_size < 0)
1907 return -EFAULT;
1908 if (0 == blk_size)
1909 ++blk_size; /* don't know why */
1910 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1911 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1912 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1913 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1914 buff_size, blk_size));
1915
1916 /* N.B. ret_sz carried into this block ... */
1917 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1918 if (mx_sc_elems < 0)
1919 return mx_sc_elems; /* most likely -ENOMEM */
1920
1921 num = scatter_elem_sz;
1922 if (unlikely(num != scatter_elem_sz_prev)) {
1923 if (num < PAGE_SIZE) {
1924 scatter_elem_sz = PAGE_SIZE;
1925 scatter_elem_sz_prev = PAGE_SIZE;
1926 } else
1927 scatter_elem_sz_prev = num;
1928 }
1929
1930 if (sdp->device->host->unchecked_isa_dma)
1931 gfp_mask |= GFP_DMA;
1932
1933 order = get_order(num);
1934retry:
1935 ret_sz = 1 << (PAGE_SHIFT + order);
1936
1937 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1938 k++, rem_sz -= ret_sz) {
1939
1940 num = (rem_sz > scatter_elem_sz_prev) ?
1941 scatter_elem_sz_prev : rem_sz;
1942
1943 schp->pages[k] = alloc_pages(gfp_mask, order);
1944 if (!schp->pages[k])
1945 goto out;
1946
1947 if (num == scatter_elem_sz_prev) {
1948 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1949 scatter_elem_sz = ret_sz;
1950 scatter_elem_sz_prev = ret_sz;
1951 }
1952 }
1953
1954 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1955 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1956 k, num, ret_sz));
1957 } /* end of for loop */
1958
1959 schp->page_order = order;
1960 schp->k_use_sg = k;
1961 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1962 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1963 k, rem_sz));
1964
1965 schp->bufflen = blk_size;
1966 if (rem_sz > 0) /* must have failed */
1967 return -ENOMEM;
1968 return 0;
1969out:
1970 for (i = 0; i < k; i++)
1971 __free_pages(schp->pages[i], order);
1972
1973 if (--order >= 0)
1974 goto retry;
1975
1976 return -ENOMEM;
1977}
1978
1979static void
1980sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1981{
1982 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1983 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1984 if (schp->pages && schp->sglist_len > 0) {
1985 if (!schp->dio_in_use) {
1986 int k;
1987
1988 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1989 SCSI_LOG_TIMEOUT(5,
1990 sg_printk(KERN_INFO, sfp->parentdp,
1991 "sg_remove_scat: k=%d, pg=0x%p\n",
1992 k, schp->pages[k]));
1993 __free_pages(schp->pages[k], schp->page_order);
1994 }
1995
1996 kfree(schp->pages);
1997 }
1998 }
1999 memset(schp, 0, sizeof (*schp));
2000}
2001
2002static int
2003sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2004{
2005 Sg_scatter_hold *schp = &srp->data;
2006 int k, num;
2007
2008 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2009 "sg_read_oxfer: num_read_xfer=%d\n",
2010 num_read_xfer));
2011 if ((!outp) || (num_read_xfer <= 0))
2012 return 0;
2013
2014 num = 1 << (PAGE_SHIFT + schp->page_order);
2015 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
2016 if (num > num_read_xfer) {
2017 if (copy_to_user(outp, page_address(schp->pages[k]),
2018 num_read_xfer))
2019 return -EFAULT;
2020 break;
2021 } else {
2022 if (copy_to_user(outp, page_address(schp->pages[k]),
2023 num))
2024 return -EFAULT;
2025 num_read_xfer -= num;
2026 if (num_read_xfer <= 0)
2027 break;
2028 outp += num;
2029 }
2030 }
2031
2032 return 0;
2033}
2034
2035static void
2036sg_build_reserve(Sg_fd * sfp, int req_size)
2037{
2038 Sg_scatter_hold *schp = &sfp->reserve;
2039
2040 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2041 "sg_build_reserve: req_size=%d\n", req_size));
2042 do {
2043 if (req_size < PAGE_SIZE)
2044 req_size = PAGE_SIZE;
2045 if (0 == sg_build_indirect(schp, sfp, req_size))
2046 return;
2047 else
2048 sg_remove_scat(sfp, schp);
2049 req_size >>= 1; /* divide by 2 */
2050 } while (req_size > (PAGE_SIZE / 2));
2051}
2052
2053static void
2054sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2055{
2056 Sg_scatter_hold *req_schp = &srp->data;
2057 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2058 int k, num, rem;
2059
2060 srp->res_used = 1;
2061 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2062 "sg_link_reserve: size=%d\n", size));
2063 rem = size;
2064
2065 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2066 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2067 if (rem <= num) {
2068 req_schp->k_use_sg = k + 1;
2069 req_schp->sglist_len = rsv_schp->sglist_len;
2070 req_schp->pages = rsv_schp->pages;
2071
2072 req_schp->bufflen = size;
2073 req_schp->page_order = rsv_schp->page_order;
2074 break;
2075 } else
2076 rem -= num;
2077 }
2078
2079 if (k >= rsv_schp->k_use_sg)
2080 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2081 "sg_link_reserve: BAD size\n"));
2082}
2083
2084static void
2085sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2086{
2087 Sg_scatter_hold *req_schp = &srp->data;
2088
2089 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2090 "sg_unlink_reserve: req->k_use_sg=%d\n",
2091 (int) req_schp->k_use_sg));
2092 req_schp->k_use_sg = 0;
2093 req_schp->bufflen = 0;
2094 req_schp->pages = NULL;
2095 req_schp->page_order = 0;
2096 req_schp->sglist_len = 0;
2097 srp->res_used = 0;
2098 /* Called without mutex lock to avoid deadlock */
2099 sfp->res_in_use = 0;
2100}
2101
2102static Sg_request *
2103sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2104{
2105 Sg_request *resp;
2106 unsigned long iflags;
2107
2108 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2109 list_for_each_entry(resp, &sfp->rq_list, entry) {
2110 /* look for requests that are ready + not SG_IO owned */
2111 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2112 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2113 resp->done = 2; /* guard against other readers */
2114 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2115 return resp;
2116 }
2117 }
2118 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2119 return NULL;
2120}
2121
2122/* always adds to end of list */
2123static Sg_request *
2124sg_add_request(Sg_fd * sfp)
2125{
2126 int k;
2127 unsigned long iflags;
2128 Sg_request *rp = sfp->req_arr;
2129
2130 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2131 if (!list_empty(&sfp->rq_list)) {
2132 if (!sfp->cmd_q)
2133 goto out_unlock;
2134
2135 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2136 if (!rp->parentfp)
2137 break;
2138 }
2139 if (k >= SG_MAX_QUEUE)
2140 goto out_unlock;
2141 }
2142 memset(rp, 0, sizeof (Sg_request));
2143 rp->parentfp = sfp;
2144 rp->header.duration = jiffies_to_msecs(jiffies);
2145 list_add_tail(&rp->entry, &sfp->rq_list);
2146 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2147 return rp;
2148out_unlock:
2149 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2150 return NULL;
2151}
2152
2153/* Return of 1 for found; 0 for not found */
2154static int
2155sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2156{
2157 unsigned long iflags;
2158 int res = 0;
2159
2160 if (!sfp || !srp || list_empty(&sfp->rq_list))
2161 return res;
2162 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2163 if (!list_empty(&srp->entry)) {
2164 list_del(&srp->entry);
2165 srp->parentfp = NULL;
2166 res = 1;
2167 }
2168 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2169 return res;
2170}
2171
2172static Sg_fd *
2173sg_add_sfp(Sg_device * sdp)
2174{
2175 Sg_fd *sfp;
2176 unsigned long iflags;
2177 int bufflen;
2178
2179 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2180 if (!sfp)
2181 return ERR_PTR(-ENOMEM);
2182
2183 init_waitqueue_head(&sfp->read_wait);
2184 rwlock_init(&sfp->rq_list_lock);
2185 INIT_LIST_HEAD(&sfp->rq_list);
2186 kref_init(&sfp->f_ref);
2187 mutex_init(&sfp->f_mutex);
2188 sfp->timeout = SG_DEFAULT_TIMEOUT;
2189 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2190 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2191 sfp->cmd_q = SG_DEF_COMMAND_Q;
2192 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2193 sfp->parentdp = sdp;
2194 write_lock_irqsave(&sdp->sfd_lock, iflags);
2195 if (atomic_read(&sdp->detaching)) {
2196 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2197 kfree(sfp);
2198 return ERR_PTR(-ENODEV);
2199 }
2200 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2201 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2202 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2203 "sg_add_sfp: sfp=0x%p\n", sfp));
2204 if (unlikely(sg_big_buff != def_reserved_size))
2205 sg_big_buff = def_reserved_size;
2206
2207 bufflen = min_t(int, sg_big_buff,
2208 max_sectors_bytes(sdp->device->request_queue));
2209 sg_build_reserve(sfp, bufflen);
2210 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2211 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2212 sfp->reserve.bufflen,
2213 sfp->reserve.k_use_sg));
2214
2215 kref_get(&sdp->d_ref);
2216 __module_get(THIS_MODULE);
2217 return sfp;
2218}
2219
2220static void
2221sg_remove_sfp_usercontext(struct work_struct *work)
2222{
2223 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2224 struct sg_device *sdp = sfp->parentdp;
2225 Sg_request *srp;
2226 unsigned long iflags;
2227
2228 /* Cleanup any responses which were never read(). */
2229 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2230 while (!list_empty(&sfp->rq_list)) {
2231 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2232 sg_finish_rem_req(srp);
2233 list_del(&srp->entry);
2234 srp->parentfp = NULL;
2235 }
2236 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2237
2238 if (sfp->reserve.bufflen > 0) {
2239 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2240 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2241 (int) sfp->reserve.bufflen,
2242 (int) sfp->reserve.k_use_sg));
2243 sg_remove_scat(sfp, &sfp->reserve);
2244 }
2245
2246 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2247 "sg_remove_sfp: sfp=0x%p\n", sfp));
2248 kfree(sfp);
2249
2250 scsi_device_put(sdp->device);
2251 kref_put(&sdp->d_ref, sg_device_destroy);
2252 module_put(THIS_MODULE);
2253}
2254
2255static void
2256sg_remove_sfp(struct kref *kref)
2257{
2258 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2259 struct sg_device *sdp = sfp->parentdp;
2260 unsigned long iflags;
2261
2262 write_lock_irqsave(&sdp->sfd_lock, iflags);
2263 list_del(&sfp->sfd_siblings);
2264 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2265
2266 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2267 schedule_work(&sfp->ew.work);
2268}
2269
2270#ifdef CONFIG_SCSI_PROC_FS
2271static int
2272sg_idr_max_id(int id, void *p, void *data)
2273{
2274 int *k = data;
2275
2276 if (*k < id)
2277 *k = id;
2278
2279 return 0;
2280}
2281
2282static int
2283sg_last_dev(void)
2284{
2285 int k = -1;
2286 unsigned long iflags;
2287
2288 read_lock_irqsave(&sg_index_lock, iflags);
2289 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2290 read_unlock_irqrestore(&sg_index_lock, iflags);
2291 return k + 1; /* origin 1 */
2292}
2293#endif
2294
2295/* must be called with sg_index_lock held */
2296static Sg_device *sg_lookup_dev(int dev)
2297{
2298 return idr_find(&sg_index_idr, dev);
2299}
2300
2301static Sg_device *
2302sg_get_dev(int dev)
2303{
2304 struct sg_device *sdp;
2305 unsigned long flags;
2306
2307 read_lock_irqsave(&sg_index_lock, flags);
2308 sdp = sg_lookup_dev(dev);
2309 if (!sdp)
2310 sdp = ERR_PTR(-ENXIO);
2311 else if (atomic_read(&sdp->detaching)) {
2312 /* If sdp->detaching, then the refcount may already be 0, in
2313 * which case it would be a bug to do kref_get().
2314 */
2315 sdp = ERR_PTR(-ENODEV);
2316 } else
2317 kref_get(&sdp->d_ref);
2318 read_unlock_irqrestore(&sg_index_lock, flags);
2319
2320 return sdp;
2321}
2322
2323#ifdef CONFIG_SCSI_PROC_FS
2324static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2325
2326static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2327static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2328 size_t count, loff_t *off);
2329static const struct proc_ops adio_proc_ops = {
2330 .proc_open = sg_proc_single_open_adio,
2331 .proc_read = seq_read,
2332 .proc_lseek = seq_lseek,
2333 .proc_write = sg_proc_write_adio,
2334 .proc_release = single_release,
2335};
2336
2337static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2338static ssize_t sg_proc_write_dressz(struct file *filp,
2339 const char __user *buffer, size_t count, loff_t *off);
2340static const struct proc_ops dressz_proc_ops = {
2341 .proc_open = sg_proc_single_open_dressz,
2342 .proc_read = seq_read,
2343 .proc_lseek = seq_lseek,
2344 .proc_write = sg_proc_write_dressz,
2345 .proc_release = single_release,
2346};
2347
2348static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2349static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2350static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2351static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2352static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2353static void dev_seq_stop(struct seq_file *s, void *v);
2354static const struct seq_operations dev_seq_ops = {
2355 .start = dev_seq_start,
2356 .next = dev_seq_next,
2357 .stop = dev_seq_stop,
2358 .show = sg_proc_seq_show_dev,
2359};
2360
2361static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2362static const struct seq_operations devstrs_seq_ops = {
2363 .start = dev_seq_start,
2364 .next = dev_seq_next,
2365 .stop = dev_seq_stop,
2366 .show = sg_proc_seq_show_devstrs,
2367};
2368
2369static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2370static const struct seq_operations debug_seq_ops = {
2371 .start = dev_seq_start,
2372 .next = dev_seq_next,
2373 .stop = dev_seq_stop,
2374 .show = sg_proc_seq_show_debug,
2375};
2376
2377static int
2378sg_proc_init(void)
2379{
2380 struct proc_dir_entry *p;
2381
2382 p = proc_mkdir("scsi/sg", NULL);
2383 if (!p)
2384 return 1;
2385
2386 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_proc_ops);
2387 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);
2388 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_proc_ops);
2389 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr);
2390 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops);
2391 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops);
2392 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version);
2393 return 0;
2394}
2395
2396
2397static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2398{
2399 seq_printf(s, "%d\n", *((int *)s->private));
2400 return 0;
2401}
2402
2403static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2404{
2405 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2406}
2407
2408static ssize_t
2409sg_proc_write_adio(struct file *filp, const char __user *buffer,
2410 size_t count, loff_t *off)
2411{
2412 int err;
2413 unsigned long num;
2414
2415 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2416 return -EACCES;
2417 err = kstrtoul_from_user(buffer, count, 0, &num);
2418 if (err)
2419 return err;
2420 sg_allow_dio = num ? 1 : 0;
2421 return count;
2422}
2423
2424static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2425{
2426 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2427}
2428
2429static ssize_t
2430sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2431 size_t count, loff_t *off)
2432{
2433 int err;
2434 unsigned long k = ULONG_MAX;
2435
2436 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2437 return -EACCES;
2438
2439 err = kstrtoul_from_user(buffer, count, 0, &k);
2440 if (err)
2441 return err;
2442 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2443 sg_big_buff = k;
2444 return count;
2445 }
2446 return -ERANGE;
2447}
2448
2449static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2450{
2451 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2452 sg_version_date);
2453 return 0;
2454}
2455
2456static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2457{
2458 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2459 return 0;
2460}
2461
2462struct sg_proc_deviter {
2463 loff_t index;
2464 size_t max;
2465};
2466
2467static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2468{
2469 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2470
2471 s->private = it;
2472 if (! it)
2473 return NULL;
2474
2475 it->index = *pos;
2476 it->max = sg_last_dev();
2477 if (it->index >= it->max)
2478 return NULL;
2479 return it;
2480}
2481
2482static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2483{
2484 struct sg_proc_deviter * it = s->private;
2485
2486 *pos = ++it->index;
2487 return (it->index < it->max) ? it : NULL;
2488}
2489
2490static void dev_seq_stop(struct seq_file *s, void *v)
2491{
2492 kfree(s->private);
2493}
2494
2495static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2496{
2497 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2498 Sg_device *sdp;
2499 struct scsi_device *scsidp;
2500 unsigned long iflags;
2501
2502 read_lock_irqsave(&sg_index_lock, iflags);
2503 sdp = it ? sg_lookup_dev(it->index) : NULL;
2504 if ((NULL == sdp) || (NULL == sdp->device) ||
2505 (atomic_read(&sdp->detaching)))
2506 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2507 else {
2508 scsidp = sdp->device;
2509 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2510 scsidp->host->host_no, scsidp->channel,
2511 scsidp->id, scsidp->lun, (int) scsidp->type,
2512 1,
2513 (int) scsidp->queue_depth,
2514 (int) atomic_read(&scsidp->device_busy),
2515 (int) scsi_device_online(scsidp));
2516 }
2517 read_unlock_irqrestore(&sg_index_lock, iflags);
2518 return 0;
2519}
2520
2521static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2522{
2523 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2524 Sg_device *sdp;
2525 struct scsi_device *scsidp;
2526 unsigned long iflags;
2527
2528 read_lock_irqsave(&sg_index_lock, iflags);
2529 sdp = it ? sg_lookup_dev(it->index) : NULL;
2530 scsidp = sdp ? sdp->device : NULL;
2531 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2532 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2533 scsidp->vendor, scsidp->model, scsidp->rev);
2534 else
2535 seq_puts(s, "<no active device>\n");
2536 read_unlock_irqrestore(&sg_index_lock, iflags);
2537 return 0;
2538}
2539
2540/* must be called while holding sg_index_lock */
2541static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2542{
2543 int k, new_interface, blen, usg;
2544 Sg_request *srp;
2545 Sg_fd *fp;
2546 const sg_io_hdr_t *hp;
2547 const char * cp;
2548 unsigned int ms;
2549
2550 k = 0;
2551 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2552 k++;
2553 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2554 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2555 "(res)sgat=%d low_dma=%d\n", k,
2556 jiffies_to_msecs(fp->timeout),
2557 fp->reserve.bufflen,
2558 (int) fp->reserve.k_use_sg,
2559 (int) sdp->device->host->unchecked_isa_dma);
2560 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2561 (int) fp->cmd_q, (int) fp->force_packid,
2562 (int) fp->keep_orphan);
2563 list_for_each_entry(srp, &fp->rq_list, entry) {
2564 hp = &srp->header;
2565 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2566 if (srp->res_used) {
2567 if (new_interface &&
2568 (SG_FLAG_MMAP_IO & hp->flags))
2569 cp = " mmap>> ";
2570 else
2571 cp = " rb>> ";
2572 } else {
2573 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2574 cp = " dio>> ";
2575 else
2576 cp = " ";
2577 }
2578 seq_puts(s, cp);
2579 blen = srp->data.bufflen;
2580 usg = srp->data.k_use_sg;
2581 seq_puts(s, srp->done ?
2582 ((1 == srp->done) ? "rcv:" : "fin:")
2583 : "act:");
2584 seq_printf(s, " id=%d blen=%d",
2585 srp->header.pack_id, blen);
2586 if (srp->done)
2587 seq_printf(s, " dur=%d", hp->duration);
2588 else {
2589 ms = jiffies_to_msecs(jiffies);
2590 seq_printf(s, " t_o/elap=%d/%d",
2591 (new_interface ? hp->timeout :
2592 jiffies_to_msecs(fp->timeout)),
2593 (ms > hp->duration ? ms - hp->duration : 0));
2594 }
2595 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2596 (int) srp->data.cmd_opcode);
2597 }
2598 if (list_empty(&fp->rq_list))
2599 seq_puts(s, " No requests active\n");
2600 read_unlock(&fp->rq_list_lock);
2601 }
2602}
2603
2604static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2605{
2606 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2607 Sg_device *sdp;
2608 unsigned long iflags;
2609
2610 if (it && (0 == it->index))
2611 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2612 (int)it->max, sg_big_buff);
2613
2614 read_lock_irqsave(&sg_index_lock, iflags);
2615 sdp = it ? sg_lookup_dev(it->index) : NULL;
2616 if (NULL == sdp)
2617 goto skip;
2618 read_lock(&sdp->sfd_lock);
2619 if (!list_empty(&sdp->sfds)) {
2620 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2621 if (atomic_read(&sdp->detaching))
2622 seq_puts(s, "detaching pending close ");
2623 else if (sdp->device) {
2624 struct scsi_device *scsidp = sdp->device;
2625
2626 seq_printf(s, "%d:%d:%d:%llu em=%d",
2627 scsidp->host->host_no,
2628 scsidp->channel, scsidp->id,
2629 scsidp->lun,
2630 scsidp->host->hostt->emulated);
2631 }
2632 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2633 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2634 sg_proc_debug_helper(s, sdp);
2635 }
2636 read_unlock(&sdp->sfd_lock);
2637skip:
2638 read_unlock_irqrestore(&sg_index_lock, iflags);
2639 return 0;
2640}
2641
2642#endif /* CONFIG_SCSI_PROC_FS */
2643
2644module_init(init_sg);
2645module_exit(exit_sg);