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