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