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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/major.h>
35#include <linux/slab.h>
36#include <linux/fcntl.h>
37#include <linux/init.h>
38#include <linux/poll.h>
39#include <linux/moduleparam.h>
40#include <linux/cdev.h>
41#include <linux/idr.h>
42#include <linux/seq_file.h>
43#include <linux/blkdev.h>
44#include <linux/delay.h>
45#include <linux/blktrace_api.h>
46#include <linux/mutex.h>
47#include <linux/atomic.h>
48#include <linux/ratelimit.h>
49#include <linux/uio.h>
50#include <linux/cred.h> /* for sg_check_file_access() */
51
52#include <scsi/scsi.h>
53#include <scsi/scsi_cmnd.h>
54#include <scsi/scsi_dbg.h>
55#include <scsi/scsi_device.h>
56#include <scsi/scsi_driver.h>
57#include <scsi/scsi_eh.h>
58#include <scsi/scsi_host.h>
59#include <scsi/scsi_ioctl.h>
60#include <scsi/scsi_tcq.h>
61#include <scsi/sg.h>
62
63#include "scsi_logging.h"
64
65#ifdef CONFIG_SCSI_PROC_FS
66#include <linux/proc_fs.h>
67static char *sg_version_date = "20140603";
68
69static int sg_proc_init(void);
70#endif
71
72#define SG_ALLOW_DIO_DEF 0
73
74#define SG_MAX_DEVS (1 << MINORBITS)
75
76/* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type
77 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater
78 * than 16 bytes are "variable length" whose length is a multiple of 4
79 */
80#define SG_MAX_CDB_SIZE 252
81
82#define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
83
84static int sg_big_buff = SG_DEF_RESERVED_SIZE;
85/* N.B. This variable is readable and writeable via
86 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
87 of this size (or less if there is not enough memory) will be reserved
88 for use by this file descriptor. [Deprecated usage: this variable is also
89 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
90 the kernel (i.e. it is not a module).] */
91static int def_reserved_size = -1; /* picks up init parameter */
92static int sg_allow_dio = SG_ALLOW_DIO_DEF;
93
94static int scatter_elem_sz = SG_SCATTER_SZ;
95static int scatter_elem_sz_prev = SG_SCATTER_SZ;
96
97#define SG_SECTOR_SZ 512
98
99static int sg_add_device(struct device *);
100static void sg_remove_device(struct device *);
101
102static DEFINE_IDR(sg_index_idr);
103static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
104 file descriptor list for device */
105
106static struct class_interface sg_interface = {
107 .add_dev = sg_add_device,
108 .remove_dev = sg_remove_device,
109};
110
111typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
112 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
113 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
114 unsigned bufflen; /* Size of (aggregate) data buffer */
115 struct page **pages;
116 int page_order;
117 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
118 unsigned char cmd_opcode; /* first byte of command */
119} Sg_scatter_hold;
120
121struct sg_device; /* forward declarations */
122struct sg_fd;
123
124typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
125 struct list_head entry; /* list entry */
126 struct sg_fd *parentfp; /* NULL -> not in use */
127 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
128 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
129 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
130 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
131 char orphan; /* 1 -> drop on sight, 0 -> normal */
132 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
133 /* done protected by rq_list_lock */
134 char done; /* 0->before bh, 1->before read, 2->read */
135 struct request *rq;
136 struct bio *bio;
137 struct execute_work ew;
138} Sg_request;
139
140typedef struct sg_fd { /* holds the state of a file descriptor */
141 struct list_head sfd_siblings; /* protected by device's sfd_lock */
142 struct sg_device *parentdp; /* owning device */
143 wait_queue_head_t read_wait; /* queue read until command done */
144 rwlock_t rq_list_lock; /* protect access to list in req_arr */
145 struct mutex f_mutex; /* protect against changes in this fd */
146 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
147 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
148 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
149 struct list_head rq_list; /* head of request list */
150 struct fasync_struct *async_qp; /* used by asynchronous notification */
151 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
152 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
153 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
154 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
155 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
156 char mmap_called; /* 0 -> mmap() never called on this fd */
157 char res_in_use; /* 1 -> 'reserve' array in use */
158 struct kref f_ref;
159 struct execute_work ew;
160} Sg_fd;
161
162typedef struct sg_device { /* holds the state of each scsi generic device */
163 struct scsi_device *device;
164 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */
165 struct mutex open_rel_lock; /* held when in open() or release() */
166 int sg_tablesize; /* adapter's max scatter-gather table size */
167 u32 index; /* device index number */
168 struct list_head sfds;
169 rwlock_t sfd_lock; /* protect access to sfd list */
170 atomic_t detaching; /* 0->device usable, 1->device detaching */
171 bool exclude; /* 1->open(O_EXCL) succeeded and is active */
172 int open_cnt; /* count of opens (perhaps < num(sfds) ) */
173 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
174 char name[DISK_NAME_LEN];
175 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
176 struct kref d_ref;
177} Sg_device;
178
179/* tasklet or soft irq callback */
180static enum rq_end_io_ret sg_rq_end_io(struct request *rq, blk_status_t status);
181static int sg_start_req(Sg_request *srp, unsigned char *cmd);
182static int sg_finish_rem_req(Sg_request * srp);
183static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
184static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
185 Sg_request * srp);
186static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
187 const char __user *buf, size_t count, int blocking,
188 int read_only, int sg_io_owned, Sg_request **o_srp);
189static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
190 unsigned char *cmnd, int timeout, int blocking);
191static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
192static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
193static void sg_build_reserve(Sg_fd * sfp, int req_size);
194static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
195static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
196static Sg_fd *sg_add_sfp(Sg_device * sdp);
197static void sg_remove_sfp(struct kref *);
198static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy);
199static Sg_request *sg_add_request(Sg_fd * sfp);
200static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
201static Sg_device *sg_get_dev(int dev);
202static void sg_device_destroy(struct kref *kref);
203
204#define SZ_SG_HEADER sizeof(struct sg_header)
205#define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
206#define SZ_SG_IOVEC sizeof(sg_iovec_t)
207#define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
208
209#define sg_printk(prefix, sdp, fmt, a...) \
210 sdev_prefix_printk(prefix, (sdp)->device, (sdp)->name, fmt, ##a)
211
212/*
213 * The SCSI interfaces that use read() and write() as an asynchronous variant of
214 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways
215 * to trigger read() and write() calls from various contexts with elevated
216 * privileges. This can lead to kernel memory corruption (e.g. if these
217 * interfaces are called through splice()) and privilege escalation inside
218 * userspace (e.g. if a process with access to such a device passes a file
219 * descriptor to a SUID binary as stdin/stdout/stderr).
220 *
221 * This function provides protection for the legacy API by restricting the
222 * calling context.
223 */
224static int sg_check_file_access(struct file *filp, const char *caller)
225{
226 if (filp->f_cred != current_real_cred()) {
227 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
228 caller, task_tgid_vnr(current), current->comm);
229 return -EPERM;
230 }
231 return 0;
232}
233
234static int sg_allow_access(struct file *filp, unsigned char *cmd)
235{
236 struct sg_fd *sfp = filp->private_data;
237
238 if (sfp->parentdp->device->type == TYPE_SCANNER)
239 return 0;
240 if (!scsi_cmd_allowed(cmd, filp->f_mode & FMODE_WRITE))
241 return -EPERM;
242 return 0;
243}
244
245static int
246open_wait(Sg_device *sdp, int flags)
247{
248 int retval = 0;
249
250 if (flags & O_EXCL) {
251 while (sdp->open_cnt > 0) {
252 mutex_unlock(&sdp->open_rel_lock);
253 retval = wait_event_interruptible(sdp->open_wait,
254 (atomic_read(&sdp->detaching) ||
255 !sdp->open_cnt));
256 mutex_lock(&sdp->open_rel_lock);
257
258 if (retval) /* -ERESTARTSYS */
259 return retval;
260 if (atomic_read(&sdp->detaching))
261 return -ENODEV;
262 }
263 } else {
264 while (sdp->exclude) {
265 mutex_unlock(&sdp->open_rel_lock);
266 retval = wait_event_interruptible(sdp->open_wait,
267 (atomic_read(&sdp->detaching) ||
268 !sdp->exclude));
269 mutex_lock(&sdp->open_rel_lock);
270
271 if (retval) /* -ERESTARTSYS */
272 return retval;
273 if (atomic_read(&sdp->detaching))
274 return -ENODEV;
275 }
276 }
277
278 return retval;
279}
280
281/* Returns 0 on success, else a negated errno value */
282static int
283sg_open(struct inode *inode, struct file *filp)
284{
285 int dev = iminor(inode);
286 int flags = filp->f_flags;
287 struct request_queue *q;
288 Sg_device *sdp;
289 Sg_fd *sfp;
290 int retval;
291
292 nonseekable_open(inode, filp);
293 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
294 return -EPERM; /* Can't lock it with read only access */
295 sdp = sg_get_dev(dev);
296 if (IS_ERR(sdp))
297 return PTR_ERR(sdp);
298
299 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
300 "sg_open: flags=0x%x\n", flags));
301
302 /* This driver's module count bumped by fops_get in <linux/fs.h> */
303 /* Prevent the device driver from vanishing while we sleep */
304 retval = scsi_device_get(sdp->device);
305 if (retval)
306 goto sg_put;
307
308 retval = scsi_autopm_get_device(sdp->device);
309 if (retval)
310 goto sdp_put;
311
312 /* scsi_block_when_processing_errors() may block so bypass
313 * check if O_NONBLOCK. Permits SCSI commands to be issued
314 * during error recovery. Tread carefully. */
315 if (!((flags & O_NONBLOCK) ||
316 scsi_block_when_processing_errors(sdp->device))) {
317 retval = -ENXIO;
318 /* we are in error recovery for this device */
319 goto error_out;
320 }
321
322 mutex_lock(&sdp->open_rel_lock);
323 if (flags & O_NONBLOCK) {
324 if (flags & O_EXCL) {
325 if (sdp->open_cnt > 0) {
326 retval = -EBUSY;
327 goto error_mutex_locked;
328 }
329 } else {
330 if (sdp->exclude) {
331 retval = -EBUSY;
332 goto error_mutex_locked;
333 }
334 }
335 } else {
336 retval = open_wait(sdp, flags);
337 if (retval) /* -ERESTARTSYS or -ENODEV */
338 goto error_mutex_locked;
339 }
340
341 /* N.B. at this point we are holding the open_rel_lock */
342 if (flags & O_EXCL)
343 sdp->exclude = true;
344
345 if (sdp->open_cnt < 1) { /* no existing opens */
346 sdp->sgdebug = 0;
347 q = sdp->device->request_queue;
348 sdp->sg_tablesize = queue_max_segments(q);
349 }
350 sfp = sg_add_sfp(sdp);
351 if (IS_ERR(sfp)) {
352 retval = PTR_ERR(sfp);
353 goto out_undo;
354 }
355
356 filp->private_data = sfp;
357 sdp->open_cnt++;
358 mutex_unlock(&sdp->open_rel_lock);
359
360 retval = 0;
361sg_put:
362 kref_put(&sdp->d_ref, sg_device_destroy);
363 return retval;
364
365out_undo:
366 if (flags & O_EXCL) {
367 sdp->exclude = false; /* undo if error */
368 wake_up_interruptible(&sdp->open_wait);
369 }
370error_mutex_locked:
371 mutex_unlock(&sdp->open_rel_lock);
372error_out:
373 scsi_autopm_put_device(sdp->device);
374sdp_put:
375 scsi_device_put(sdp->device);
376 goto sg_put;
377}
378
379/* Release resources associated with a successful sg_open()
380 * Returns 0 on success, else a negated errno value */
381static int
382sg_release(struct inode *inode, struct file *filp)
383{
384 Sg_device *sdp;
385 Sg_fd *sfp;
386
387 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
388 return -ENXIO;
389 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
390
391 mutex_lock(&sdp->open_rel_lock);
392 scsi_autopm_put_device(sdp->device);
393 kref_put(&sfp->f_ref, sg_remove_sfp);
394 sdp->open_cnt--;
395
396 /* possibly many open()s waiting on exlude clearing, start many;
397 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
398 if (sdp->exclude) {
399 sdp->exclude = false;
400 wake_up_interruptible_all(&sdp->open_wait);
401 } else if (0 == sdp->open_cnt) {
402 wake_up_interruptible(&sdp->open_wait);
403 }
404 mutex_unlock(&sdp->open_rel_lock);
405 return 0;
406}
407
408static int get_sg_io_pack_id(int *pack_id, void __user *buf, size_t count)
409{
410 struct sg_header __user *old_hdr = buf;
411 int reply_len;
412
413 if (count >= SZ_SG_HEADER) {
414 /* negative reply_len means v3 format, otherwise v1/v2 */
415 if (get_user(reply_len, &old_hdr->reply_len))
416 return -EFAULT;
417
418 if (reply_len >= 0)
419 return get_user(*pack_id, &old_hdr->pack_id);
420
421 if (in_compat_syscall() &&
422 count >= sizeof(struct compat_sg_io_hdr)) {
423 struct compat_sg_io_hdr __user *hp = buf;
424
425 return get_user(*pack_id, &hp->pack_id);
426 }
427
428 if (count >= sizeof(struct sg_io_hdr)) {
429 struct sg_io_hdr __user *hp = buf;
430
431 return get_user(*pack_id, &hp->pack_id);
432 }
433 }
434
435 /* no valid header was passed, so ignore the pack_id */
436 *pack_id = -1;
437 return 0;
438}
439
440static ssize_t
441sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
442{
443 Sg_device *sdp;
444 Sg_fd *sfp;
445 Sg_request *srp;
446 int req_pack_id = -1;
447 bool busy;
448 sg_io_hdr_t *hp;
449 struct sg_header *old_hdr;
450 int retval;
451
452 /*
453 * This could cause a response to be stranded. Close the associated
454 * file descriptor to free up any resources being held.
455 */
456 retval = sg_check_file_access(filp, __func__);
457 if (retval)
458 return retval;
459
460 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
461 return -ENXIO;
462 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
463 "sg_read: count=%d\n", (int) count));
464
465 if (sfp->force_packid)
466 retval = get_sg_io_pack_id(&req_pack_id, buf, count);
467 if (retval)
468 return retval;
469
470 srp = sg_get_rq_mark(sfp, req_pack_id, &busy);
471 if (!srp) { /* now wait on packet to arrive */
472 if (filp->f_flags & O_NONBLOCK)
473 return -EAGAIN;
474 retval = wait_event_interruptible(sfp->read_wait,
475 ((srp = sg_get_rq_mark(sfp, req_pack_id, &busy)) ||
476 (!busy && atomic_read(&sdp->detaching))));
477 if (!srp)
478 /* signal or detaching */
479 return retval ? retval : -ENODEV;
480 }
481 if (srp->header.interface_id != '\0')
482 return sg_new_read(sfp, buf, count, srp);
483
484 hp = &srp->header;
485 old_hdr = kzalloc(SZ_SG_HEADER, GFP_KERNEL);
486 if (!old_hdr)
487 return -ENOMEM;
488
489 old_hdr->reply_len = (int) hp->timeout;
490 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
491 old_hdr->pack_id = hp->pack_id;
492 old_hdr->twelve_byte =
493 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
494 old_hdr->target_status = hp->masked_status;
495 old_hdr->host_status = hp->host_status;
496 old_hdr->driver_status = hp->driver_status;
497 if ((CHECK_CONDITION & hp->masked_status) ||
498 (srp->sense_b[0] & 0x70) == 0x70) {
499 old_hdr->driver_status = DRIVER_SENSE;
500 memcpy(old_hdr->sense_buffer, srp->sense_b,
501 sizeof (old_hdr->sense_buffer));
502 }
503 switch (hp->host_status) {
504 /* This setup of 'result' is for backward compatibility and is best
505 ignored by the user who should use target, host + driver status */
506 case DID_OK:
507 case DID_PASSTHROUGH:
508 case DID_SOFT_ERROR:
509 old_hdr->result = 0;
510 break;
511 case DID_NO_CONNECT:
512 case DID_BUS_BUSY:
513 case DID_TIME_OUT:
514 old_hdr->result = EBUSY;
515 break;
516 case DID_BAD_TARGET:
517 case DID_ABORT:
518 case DID_PARITY:
519 case DID_RESET:
520 case DID_BAD_INTR:
521 old_hdr->result = EIO;
522 break;
523 case DID_ERROR:
524 old_hdr->result = (srp->sense_b[0] == 0 &&
525 hp->masked_status == GOOD) ? 0 : EIO;
526 break;
527 default:
528 old_hdr->result = EIO;
529 break;
530 }
531
532 /* Now copy the result back to the user buffer. */
533 if (count >= SZ_SG_HEADER) {
534 if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
535 retval = -EFAULT;
536 goto free_old_hdr;
537 }
538 buf += SZ_SG_HEADER;
539 if (count > old_hdr->reply_len)
540 count = old_hdr->reply_len;
541 if (count > SZ_SG_HEADER) {
542 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
543 retval = -EFAULT;
544 goto free_old_hdr;
545 }
546 }
547 } else
548 count = (old_hdr->result == 0) ? 0 : -EIO;
549 sg_finish_rem_req(srp);
550 sg_remove_request(sfp, srp);
551 retval = count;
552free_old_hdr:
553 kfree(old_hdr);
554 return retval;
555}
556
557static ssize_t
558sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
559{
560 sg_io_hdr_t *hp = &srp->header;
561 int err = 0, err2;
562 int len;
563
564 if (in_compat_syscall()) {
565 if (count < sizeof(struct compat_sg_io_hdr)) {
566 err = -EINVAL;
567 goto err_out;
568 }
569 } else if (count < SZ_SG_IO_HDR) {
570 err = -EINVAL;
571 goto err_out;
572 }
573 hp->sb_len_wr = 0;
574 if ((hp->mx_sb_len > 0) && hp->sbp) {
575 if ((CHECK_CONDITION & hp->masked_status) ||
576 (srp->sense_b[0] & 0x70) == 0x70) {
577 int sb_len = SCSI_SENSE_BUFFERSIZE;
578 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
579 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
580 len = (len > sb_len) ? sb_len : len;
581 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
582 err = -EFAULT;
583 goto err_out;
584 }
585 hp->driver_status = DRIVER_SENSE;
586 hp->sb_len_wr = len;
587 }
588 }
589 if (hp->masked_status || hp->host_status || hp->driver_status)
590 hp->info |= SG_INFO_CHECK;
591 err = put_sg_io_hdr(hp, buf);
592err_out:
593 err2 = sg_finish_rem_req(srp);
594 sg_remove_request(sfp, srp);
595 return err ? : err2 ? : count;
596}
597
598static ssize_t
599sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
600{
601 int mxsize, cmd_size, k;
602 int input_size, blocking;
603 unsigned char opcode;
604 Sg_device *sdp;
605 Sg_fd *sfp;
606 Sg_request *srp;
607 struct sg_header old_hdr;
608 sg_io_hdr_t *hp;
609 unsigned char cmnd[SG_MAX_CDB_SIZE];
610 int retval;
611
612 retval = sg_check_file_access(filp, __func__);
613 if (retval)
614 return retval;
615
616 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
617 return -ENXIO;
618 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
619 "sg_write: count=%d\n", (int) count));
620 if (atomic_read(&sdp->detaching))
621 return -ENODEV;
622 if (!((filp->f_flags & O_NONBLOCK) ||
623 scsi_block_when_processing_errors(sdp->device)))
624 return -ENXIO;
625
626 if (count < SZ_SG_HEADER)
627 return -EIO;
628 if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
629 return -EFAULT;
630 blocking = !(filp->f_flags & O_NONBLOCK);
631 if (old_hdr.reply_len < 0)
632 return sg_new_write(sfp, filp, buf, count,
633 blocking, 0, 0, NULL);
634 if (count < (SZ_SG_HEADER + 6))
635 return -EIO; /* The minimum scsi command length is 6 bytes. */
636
637 buf += SZ_SG_HEADER;
638 if (get_user(opcode, buf))
639 return -EFAULT;
640
641 if (!(srp = sg_add_request(sfp))) {
642 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
643 "sg_write: queue full\n"));
644 return -EDOM;
645 }
646 mutex_lock(&sfp->f_mutex);
647 if (sfp->next_cmd_len > 0) {
648 cmd_size = sfp->next_cmd_len;
649 sfp->next_cmd_len = 0; /* reset so only this write() effected */
650 } else {
651 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
652 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
653 cmd_size = 12;
654 }
655 mutex_unlock(&sfp->f_mutex);
656 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
657 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
658/* Determine buffer size. */
659 input_size = count - cmd_size;
660 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
661 mxsize -= SZ_SG_HEADER;
662 input_size -= SZ_SG_HEADER;
663 if (input_size < 0) {
664 sg_remove_request(sfp, srp);
665 return -EIO; /* User did not pass enough bytes for this command. */
666 }
667 hp = &srp->header;
668 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
669 hp->cmd_len = (unsigned char) cmd_size;
670 hp->iovec_count = 0;
671 hp->mx_sb_len = 0;
672 if (input_size > 0)
673 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
674 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
675 else
676 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
677 hp->dxfer_len = mxsize;
678 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
679 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
680 hp->dxferp = (char __user *)buf + cmd_size;
681 else
682 hp->dxferp = NULL;
683 hp->sbp = NULL;
684 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
685 hp->flags = input_size; /* structure abuse ... */
686 hp->pack_id = old_hdr.pack_id;
687 hp->usr_ptr = NULL;
688 if (copy_from_user(cmnd, buf, cmd_size)) {
689 sg_remove_request(sfp, srp);
690 return -EFAULT;
691 }
692 /*
693 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
694 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
695 * is a non-zero input_size, so emit a warning.
696 */
697 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
698 printk_ratelimited(KERN_WARNING
699 "sg_write: data in/out %d/%d bytes "
700 "for SCSI command 0x%x-- guessing "
701 "data in;\n program %s not setting "
702 "count and/or reply_len properly\n",
703 old_hdr.reply_len - (int)SZ_SG_HEADER,
704 input_size, (unsigned int) cmnd[0],
705 current->comm);
706 }
707 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
708 return (k < 0) ? k : count;
709}
710
711static ssize_t
712sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
713 size_t count, int blocking, int read_only, int sg_io_owned,
714 Sg_request **o_srp)
715{
716 int k;
717 Sg_request *srp;
718 sg_io_hdr_t *hp;
719 unsigned char cmnd[SG_MAX_CDB_SIZE];
720 int timeout;
721 unsigned long ul_timeout;
722
723 if (count < SZ_SG_IO_HDR)
724 return -EINVAL;
725
726 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
727 if (!(srp = sg_add_request(sfp))) {
728 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
729 "sg_new_write: queue full\n"));
730 return -EDOM;
731 }
732 srp->sg_io_owned = sg_io_owned;
733 hp = &srp->header;
734 if (get_sg_io_hdr(hp, buf)) {
735 sg_remove_request(sfp, srp);
736 return -EFAULT;
737 }
738 if (hp->interface_id != 'S') {
739 sg_remove_request(sfp, srp);
740 return -ENOSYS;
741 }
742 if (hp->flags & SG_FLAG_MMAP_IO) {
743 if (hp->dxfer_len > sfp->reserve.bufflen) {
744 sg_remove_request(sfp, srp);
745 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
746 }
747 if (hp->flags & SG_FLAG_DIRECT_IO) {
748 sg_remove_request(sfp, srp);
749 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
750 }
751 if (sfp->res_in_use) {
752 sg_remove_request(sfp, srp);
753 return -EBUSY; /* reserve buffer already being used */
754 }
755 }
756 ul_timeout = msecs_to_jiffies(srp->header.timeout);
757 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
758 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
759 sg_remove_request(sfp, srp);
760 return -EMSGSIZE;
761 }
762 if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
763 sg_remove_request(sfp, srp);
764 return -EFAULT;
765 }
766 if (read_only && sg_allow_access(file, cmnd)) {
767 sg_remove_request(sfp, srp);
768 return -EPERM;
769 }
770 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
771 if (k < 0)
772 return k;
773 if (o_srp)
774 *o_srp = srp;
775 return count;
776}
777
778static int
779sg_common_write(Sg_fd * sfp, Sg_request * srp,
780 unsigned char *cmnd, int timeout, int blocking)
781{
782 int k, at_head;
783 Sg_device *sdp = sfp->parentdp;
784 sg_io_hdr_t *hp = &srp->header;
785
786 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
787 hp->status = 0;
788 hp->masked_status = 0;
789 hp->msg_status = 0;
790 hp->info = 0;
791 hp->host_status = 0;
792 hp->driver_status = 0;
793 hp->resid = 0;
794 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
795 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
796 (int) cmnd[0], (int) hp->cmd_len));
797
798 if (hp->dxfer_len >= SZ_256M) {
799 sg_remove_request(sfp, srp);
800 return -EINVAL;
801 }
802
803 k = sg_start_req(srp, cmnd);
804 if (k) {
805 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
806 "sg_common_write: start_req err=%d\n", k));
807 sg_finish_rem_req(srp);
808 sg_remove_request(sfp, srp);
809 return k; /* probably out of space --> ENOMEM */
810 }
811 if (atomic_read(&sdp->detaching)) {
812 if (srp->bio) {
813 blk_mq_free_request(srp->rq);
814 srp->rq = NULL;
815 }
816
817 sg_finish_rem_req(srp);
818 sg_remove_request(sfp, srp);
819 return -ENODEV;
820 }
821
822 hp->duration = jiffies_to_msecs(jiffies);
823 if (hp->interface_id != '\0' && /* v3 (or later) interface */
824 (SG_FLAG_Q_AT_TAIL & hp->flags))
825 at_head = 0;
826 else
827 at_head = 1;
828
829 srp->rq->timeout = timeout;
830 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
831 srp->rq->end_io = sg_rq_end_io;
832 blk_execute_rq_nowait(srp->rq, at_head);
833 return 0;
834}
835
836static int srp_done(Sg_fd *sfp, Sg_request *srp)
837{
838 unsigned long flags;
839 int ret;
840
841 read_lock_irqsave(&sfp->rq_list_lock, flags);
842 ret = srp->done;
843 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
844 return ret;
845}
846
847static int max_sectors_bytes(struct request_queue *q)
848{
849 unsigned int max_sectors = queue_max_sectors(q);
850
851 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
852
853 return max_sectors << 9;
854}
855
856static void
857sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
858{
859 Sg_request *srp;
860 int val;
861 unsigned int ms;
862
863 val = 0;
864 list_for_each_entry(srp, &sfp->rq_list, entry) {
865 if (val >= SG_MAX_QUEUE)
866 break;
867 rinfo[val].req_state = srp->done + 1;
868 rinfo[val].problem =
869 srp->header.masked_status &
870 srp->header.host_status &
871 srp->header.driver_status;
872 if (srp->done)
873 rinfo[val].duration =
874 srp->header.duration;
875 else {
876 ms = jiffies_to_msecs(jiffies);
877 rinfo[val].duration =
878 (ms > srp->header.duration) ?
879 (ms - srp->header.duration) : 0;
880 }
881 rinfo[val].orphan = srp->orphan;
882 rinfo[val].sg_io_owned = srp->sg_io_owned;
883 rinfo[val].pack_id = srp->header.pack_id;
884 rinfo[val].usr_ptr = srp->header.usr_ptr;
885 val++;
886 }
887}
888
889#ifdef CONFIG_COMPAT
890struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */
891 char req_state;
892 char orphan;
893 char sg_io_owned;
894 char problem;
895 int pack_id;
896 compat_uptr_t usr_ptr;
897 unsigned int duration;
898 int unused;
899};
900
901static int put_compat_request_table(struct compat_sg_req_info __user *o,
902 struct sg_req_info *rinfo)
903{
904 int i;
905 for (i = 0; i < SG_MAX_QUEUE; i++) {
906 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) ||
907 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) ||
908 put_user(rinfo[i].duration, &o[i].duration) ||
909 put_user(rinfo[i].unused, &o[i].unused))
910 return -EFAULT;
911 }
912 return 0;
913}
914#endif
915
916static long
917sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp,
918 unsigned int cmd_in, void __user *p)
919{
920 int __user *ip = p;
921 int result, val, read_only;
922 Sg_request *srp;
923 unsigned long iflags;
924
925 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
926 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
927 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
928
929 switch (cmd_in) {
930 case SG_IO:
931 if (atomic_read(&sdp->detaching))
932 return -ENODEV;
933 if (!scsi_block_when_processing_errors(sdp->device))
934 return -ENXIO;
935 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
936 1, read_only, 1, &srp);
937 if (result < 0)
938 return result;
939 result = wait_event_interruptible(sfp->read_wait,
940 srp_done(sfp, srp));
941 write_lock_irq(&sfp->rq_list_lock);
942 if (srp->done) {
943 srp->done = 2;
944 write_unlock_irq(&sfp->rq_list_lock);
945 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
946 return (result < 0) ? result : 0;
947 }
948 srp->orphan = 1;
949 write_unlock_irq(&sfp->rq_list_lock);
950 return result; /* -ERESTARTSYS because signal hit process */
951 case SG_SET_TIMEOUT:
952 result = get_user(val, ip);
953 if (result)
954 return result;
955 if (val < 0)
956 return -EIO;
957 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
958 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
959 INT_MAX);
960 sfp->timeout_user = val;
961 sfp->timeout = mult_frac(val, HZ, USER_HZ);
962
963 return 0;
964 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
965 /* strange ..., for backward compatibility */
966 return sfp->timeout_user;
967 case SG_SET_FORCE_LOW_DMA:
968 /*
969 * N.B. This ioctl never worked properly, but failed to
970 * return an error value. So returning '0' to keep compability
971 * with legacy applications.
972 */
973 return 0;
974 case SG_GET_LOW_DMA:
975 return put_user(0, ip);
976 case SG_GET_SCSI_ID:
977 {
978 sg_scsi_id_t v;
979
980 if (atomic_read(&sdp->detaching))
981 return -ENODEV;
982 memset(&v, 0, sizeof(v));
983 v.host_no = sdp->device->host->host_no;
984 v.channel = sdp->device->channel;
985 v.scsi_id = sdp->device->id;
986 v.lun = sdp->device->lun;
987 v.scsi_type = sdp->device->type;
988 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun;
989 v.d_queue_depth = sdp->device->queue_depth;
990 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t)))
991 return -EFAULT;
992 return 0;
993 }
994 case SG_SET_FORCE_PACK_ID:
995 result = get_user(val, ip);
996 if (result)
997 return result;
998 sfp->force_packid = val ? 1 : 0;
999 return 0;
1000 case SG_GET_PACK_ID:
1001 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1002 list_for_each_entry(srp, &sfp->rq_list, entry) {
1003 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1004 read_unlock_irqrestore(&sfp->rq_list_lock,
1005 iflags);
1006 return put_user(srp->header.pack_id, ip);
1007 }
1008 }
1009 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1010 return put_user(-1, ip);
1011 case SG_GET_NUM_WAITING:
1012 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1013 val = 0;
1014 list_for_each_entry(srp, &sfp->rq_list, entry) {
1015 if ((1 == srp->done) && (!srp->sg_io_owned))
1016 ++val;
1017 }
1018 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1019 return put_user(val, ip);
1020 case SG_GET_SG_TABLESIZE:
1021 return put_user(sdp->sg_tablesize, ip);
1022 case SG_SET_RESERVED_SIZE:
1023 result = get_user(val, ip);
1024 if (result)
1025 return result;
1026 if (val < 0)
1027 return -EINVAL;
1028 val = min_t(int, val,
1029 max_sectors_bytes(sdp->device->request_queue));
1030 mutex_lock(&sfp->f_mutex);
1031 if (val != sfp->reserve.bufflen) {
1032 if (sfp->mmap_called ||
1033 sfp->res_in_use) {
1034 mutex_unlock(&sfp->f_mutex);
1035 return -EBUSY;
1036 }
1037
1038 sg_remove_scat(sfp, &sfp->reserve);
1039 sg_build_reserve(sfp, val);
1040 }
1041 mutex_unlock(&sfp->f_mutex);
1042 return 0;
1043 case SG_GET_RESERVED_SIZE:
1044 val = min_t(int, sfp->reserve.bufflen,
1045 max_sectors_bytes(sdp->device->request_queue));
1046 return put_user(val, ip);
1047 case SG_SET_COMMAND_Q:
1048 result = get_user(val, ip);
1049 if (result)
1050 return result;
1051 sfp->cmd_q = val ? 1 : 0;
1052 return 0;
1053 case SG_GET_COMMAND_Q:
1054 return put_user((int) sfp->cmd_q, ip);
1055 case SG_SET_KEEP_ORPHAN:
1056 result = get_user(val, ip);
1057 if (result)
1058 return result;
1059 sfp->keep_orphan = val;
1060 return 0;
1061 case SG_GET_KEEP_ORPHAN:
1062 return put_user((int) sfp->keep_orphan, ip);
1063 case SG_NEXT_CMD_LEN:
1064 result = get_user(val, ip);
1065 if (result)
1066 return result;
1067 if (val > SG_MAX_CDB_SIZE)
1068 return -ENOMEM;
1069 sfp->next_cmd_len = (val > 0) ? val : 0;
1070 return 0;
1071 case SG_GET_VERSION_NUM:
1072 return put_user(sg_version_num, ip);
1073 case SG_GET_ACCESS_COUNT:
1074 /* faked - we don't have a real access count anymore */
1075 val = (sdp->device ? 1 : 0);
1076 return put_user(val, ip);
1077 case SG_GET_REQUEST_TABLE:
1078 {
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 #ifdef CONFIG_COMPAT
1089 if (in_compat_syscall())
1090 result = put_compat_request_table(p, rinfo);
1091 else
1092 #endif
1093 result = copy_to_user(p, rinfo,
1094 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1095 result = result ? -EFAULT : 0;
1096 kfree(rinfo);
1097 return result;
1098 }
1099 case SG_EMULATED_HOST:
1100 if (atomic_read(&sdp->detaching))
1101 return -ENODEV;
1102 return put_user(sdp->device->host->hostt->emulated, ip);
1103 case SCSI_IOCTL_SEND_COMMAND:
1104 if (atomic_read(&sdp->detaching))
1105 return -ENODEV;
1106 return scsi_ioctl(sdp->device, filp->f_mode & FMODE_WRITE,
1107 cmd_in, p);
1108 case SG_SET_DEBUG:
1109 result = get_user(val, ip);
1110 if (result)
1111 return result;
1112 sdp->sgdebug = (char) val;
1113 return 0;
1114 case BLKSECTGET:
1115 return put_user(max_sectors_bytes(sdp->device->request_queue),
1116 ip);
1117 case BLKTRACESETUP:
1118 return blk_trace_setup(sdp->device->request_queue, sdp->name,
1119 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1120 NULL, p);
1121 case BLKTRACESTART:
1122 return blk_trace_startstop(sdp->device->request_queue, 1);
1123 case BLKTRACESTOP:
1124 return blk_trace_startstop(sdp->device->request_queue, 0);
1125 case BLKTRACETEARDOWN:
1126 return blk_trace_remove(sdp->device->request_queue);
1127 case SCSI_IOCTL_GET_IDLUN:
1128 case SCSI_IOCTL_GET_BUS_NUMBER:
1129 case SCSI_IOCTL_PROBE_HOST:
1130 case SG_GET_TRANSFORM:
1131 case SG_SCSI_RESET:
1132 if (atomic_read(&sdp->detaching))
1133 return -ENODEV;
1134 break;
1135 default:
1136 if (read_only)
1137 return -EPERM; /* don't know so take safe approach */
1138 break;
1139 }
1140
1141 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1142 cmd_in, filp->f_flags & O_NDELAY);
1143 if (result)
1144 return result;
1145
1146 return -ENOIOCTLCMD;
1147}
1148
1149static long
1150sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1151{
1152 void __user *p = (void __user *)arg;
1153 Sg_device *sdp;
1154 Sg_fd *sfp;
1155 int ret;
1156
1157 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1158 return -ENXIO;
1159
1160 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);
1161 if (ret != -ENOIOCTLCMD)
1162 return ret;
1163 return scsi_ioctl(sdp->device, filp->f_mode & FMODE_WRITE, cmd_in, p);
1164}
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 vm_flags_set(vma, 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 enum rq_end_io_ret
1316sg_rq_end_io(struct request *rq, blk_status_t status)
1317{
1318 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
1319 struct sg_request *srp = rq->end_io_data;
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 RQ_END_IO_NONE;
1329
1330 sfp = srp->parentfp;
1331 if (WARN_ON(sfp == NULL))
1332 return RQ_END_IO_NONE;
1333
1334 sdp = sfp->parentdp;
1335 if (unlikely(atomic_read(&sdp->detaching)))
1336 pr_info("%s: device detaching\n", __func__);
1337
1338 sense = scmd->sense_buffer;
1339 result = scmd->result;
1340 resid = scmd->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 = sg_status_byte(result);
1354 srp->header.msg_status = COMMAND_COMPLETE;
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 (scmd->sense_len)
1376 memcpy(srp->sense_b, scmd->sense_buffer, 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 blk_mq_free_request(rq);
1388
1389 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1390 if (unlikely(srp->orphan)) {
1391 if (sfp->keep_orphan)
1392 srp->sg_io_owned = 0;
1393 else
1394 done = 0;
1395 }
1396 srp->done = done;
1397 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1398
1399 if (likely(done)) {
1400 /* Now wake up any sg_read() that is waiting for this
1401 * packet.
1402 */
1403 wake_up_interruptible(&sfp->read_wait);
1404 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1405 kref_put(&sfp->f_ref, sg_remove_sfp);
1406 } else {
1407 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1408 schedule_work(&srp->ew.work);
1409 }
1410 return RQ_END_IO_NONE;
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 .compat_ioctl = compat_ptr_ioctl,
1420 .open = sg_open,
1421 .mmap = sg_mmap,
1422 .release = sg_release,
1423 .fasync = sg_fasync,
1424 .llseek = no_llseek,
1425};
1426
1427static struct class *sg_sysfs_class;
1428
1429static int sg_sysfs_valid = 0;
1430
1431static Sg_device *
1432sg_alloc(struct scsi_device *scsidp)
1433{
1434 struct request_queue *q = scsidp->request_queue;
1435 Sg_device *sdp;
1436 unsigned long iflags;
1437 int error;
1438 u32 k;
1439
1440 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1441 if (!sdp) {
1442 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1443 "failure\n", __func__);
1444 return ERR_PTR(-ENOMEM);
1445 }
1446
1447 idr_preload(GFP_KERNEL);
1448 write_lock_irqsave(&sg_index_lock, iflags);
1449
1450 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1451 if (error < 0) {
1452 if (error == -ENOSPC) {
1453 sdev_printk(KERN_WARNING, scsidp,
1454 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1455 scsidp->type, SG_MAX_DEVS - 1);
1456 error = -ENODEV;
1457 } else {
1458 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1459 "allocation Sg_device failure: %d\n",
1460 __func__, error);
1461 }
1462 goto out_unlock;
1463 }
1464 k = error;
1465
1466 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1467 "sg_alloc: dev=%d \n", k));
1468 sprintf(sdp->name, "sg%d", k);
1469 sdp->device = scsidp;
1470 mutex_init(&sdp->open_rel_lock);
1471 INIT_LIST_HEAD(&sdp->sfds);
1472 init_waitqueue_head(&sdp->open_wait);
1473 atomic_set(&sdp->detaching, 0);
1474 rwlock_init(&sdp->sfd_lock);
1475 sdp->sg_tablesize = queue_max_segments(q);
1476 sdp->index = k;
1477 kref_init(&sdp->d_ref);
1478 error = 0;
1479
1480out_unlock:
1481 write_unlock_irqrestore(&sg_index_lock, iflags);
1482 idr_preload_end();
1483
1484 if (error) {
1485 kfree(sdp);
1486 return ERR_PTR(error);
1487 }
1488 return sdp;
1489}
1490
1491static int
1492sg_add_device(struct device *cl_dev)
1493{
1494 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1495 Sg_device *sdp = NULL;
1496 struct cdev * cdev = NULL;
1497 int error;
1498 unsigned long iflags;
1499
1500 if (!blk_get_queue(scsidp->request_queue)) {
1501 pr_warn("%s: get scsi_device queue failed\n", __func__);
1502 return -ENODEV;
1503 }
1504
1505 error = -ENOMEM;
1506 cdev = cdev_alloc();
1507 if (!cdev) {
1508 pr_warn("%s: cdev_alloc failed\n", __func__);
1509 goto out;
1510 }
1511 cdev->owner = THIS_MODULE;
1512 cdev->ops = &sg_fops;
1513
1514 sdp = sg_alloc(scsidp);
1515 if (IS_ERR(sdp)) {
1516 pr_warn("%s: sg_alloc failed\n", __func__);
1517 error = PTR_ERR(sdp);
1518 goto out;
1519 }
1520
1521 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1522 if (error)
1523 goto cdev_add_err;
1524
1525 sdp->cdev = cdev;
1526 if (sg_sysfs_valid) {
1527 struct device *sg_class_member;
1528
1529 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1530 MKDEV(SCSI_GENERIC_MAJOR,
1531 sdp->index),
1532 sdp, "%s", sdp->name);
1533 if (IS_ERR(sg_class_member)) {
1534 pr_err("%s: device_create failed\n", __func__);
1535 error = PTR_ERR(sg_class_member);
1536 goto cdev_add_err;
1537 }
1538 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1539 &sg_class_member->kobj, "generic");
1540 if (error)
1541 pr_err("%s: unable to make symlink 'generic' back "
1542 "to sg%d\n", __func__, sdp->index);
1543 } else
1544 pr_warn("%s: sg_sys Invalid\n", __func__);
1545
1546 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1547 "type %d\n", sdp->index, scsidp->type);
1548
1549 dev_set_drvdata(cl_dev, sdp);
1550
1551 return 0;
1552
1553cdev_add_err:
1554 write_lock_irqsave(&sg_index_lock, iflags);
1555 idr_remove(&sg_index_idr, sdp->index);
1556 write_unlock_irqrestore(&sg_index_lock, iflags);
1557 kfree(sdp);
1558
1559out:
1560 if (cdev)
1561 cdev_del(cdev);
1562 blk_put_queue(scsidp->request_queue);
1563 return error;
1564}
1565
1566static void
1567sg_device_destroy(struct kref *kref)
1568{
1569 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1570 struct request_queue *q = sdp->device->request_queue;
1571 unsigned long flags;
1572
1573 /* CAUTION! Note that the device can still be found via idr_find()
1574 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1575 * any other cleanup.
1576 */
1577
1578 blk_trace_remove(q);
1579 blk_put_queue(q);
1580
1581 write_lock_irqsave(&sg_index_lock, flags);
1582 idr_remove(&sg_index_idr, sdp->index);
1583 write_unlock_irqrestore(&sg_index_lock, flags);
1584
1585 SCSI_LOG_TIMEOUT(3,
1586 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1587
1588 kfree(sdp);
1589}
1590
1591static void
1592sg_remove_device(struct device *cl_dev)
1593{
1594 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1595 Sg_device *sdp = dev_get_drvdata(cl_dev);
1596 unsigned long iflags;
1597 Sg_fd *sfp;
1598 int val;
1599
1600 if (!sdp)
1601 return;
1602 /* want sdp->detaching non-zero as soon as possible */
1603 val = atomic_inc_return(&sdp->detaching);
1604 if (val > 1)
1605 return; /* only want to do following once per device */
1606
1607 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1608 "%s\n", __func__));
1609
1610 read_lock_irqsave(&sdp->sfd_lock, iflags);
1611 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1612 wake_up_interruptible_all(&sfp->read_wait);
1613 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1614 }
1615 wake_up_interruptible_all(&sdp->open_wait);
1616 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1617
1618 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1619 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1620 cdev_del(sdp->cdev);
1621 sdp->cdev = NULL;
1622
1623 kref_put(&sdp->d_ref, sg_device_destroy);
1624}
1625
1626module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1627module_param_named(def_reserved_size, def_reserved_size, int,
1628 S_IRUGO | S_IWUSR);
1629module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1630
1631MODULE_AUTHOR("Douglas Gilbert");
1632MODULE_DESCRIPTION("SCSI generic (sg) driver");
1633MODULE_LICENSE("GPL");
1634MODULE_VERSION(SG_VERSION_STR);
1635MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1636
1637MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1638 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1639MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1640MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1641
1642#ifdef CONFIG_SYSCTL
1643#include <linux/sysctl.h>
1644
1645static struct ctl_table sg_sysctls[] = {
1646 {
1647 .procname = "sg-big-buff",
1648 .data = &sg_big_buff,
1649 .maxlen = sizeof(int),
1650 .mode = 0444,
1651 .proc_handler = proc_dointvec,
1652 },
1653};
1654
1655static struct ctl_table_header *hdr;
1656static void register_sg_sysctls(void)
1657{
1658 if (!hdr)
1659 hdr = register_sysctl("kernel", sg_sysctls);
1660}
1661
1662static void unregister_sg_sysctls(void)
1663{
1664 if (hdr)
1665 unregister_sysctl_table(hdr);
1666}
1667#else
1668#define register_sg_sysctls() do { } while (0)
1669#define unregister_sg_sysctls() do { } while (0)
1670#endif /* CONFIG_SYSCTL */
1671
1672static int __init
1673init_sg(void)
1674{
1675 int rc;
1676
1677 if (scatter_elem_sz < PAGE_SIZE) {
1678 scatter_elem_sz = PAGE_SIZE;
1679 scatter_elem_sz_prev = scatter_elem_sz;
1680 }
1681 if (def_reserved_size >= 0)
1682 sg_big_buff = def_reserved_size;
1683 else
1684 def_reserved_size = sg_big_buff;
1685
1686 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1687 SG_MAX_DEVS, "sg");
1688 if (rc)
1689 return rc;
1690 sg_sysfs_class = class_create("scsi_generic");
1691 if ( IS_ERR(sg_sysfs_class) ) {
1692 rc = PTR_ERR(sg_sysfs_class);
1693 goto err_out;
1694 }
1695 sg_sysfs_valid = 1;
1696 rc = scsi_register_interface(&sg_interface);
1697 if (0 == rc) {
1698#ifdef CONFIG_SCSI_PROC_FS
1699 sg_proc_init();
1700#endif /* CONFIG_SCSI_PROC_FS */
1701 return 0;
1702 }
1703 class_destroy(sg_sysfs_class);
1704 register_sg_sysctls();
1705err_out:
1706 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1707 return rc;
1708}
1709
1710static void __exit
1711exit_sg(void)
1712{
1713 unregister_sg_sysctls();
1714#ifdef CONFIG_SCSI_PROC_FS
1715 remove_proc_subtree("scsi/sg", NULL);
1716#endif /* CONFIG_SCSI_PROC_FS */
1717 scsi_unregister_interface(&sg_interface);
1718 class_destroy(sg_sysfs_class);
1719 sg_sysfs_valid = 0;
1720 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1721 SG_MAX_DEVS);
1722 idr_destroy(&sg_index_idr);
1723}
1724
1725static int
1726sg_start_req(Sg_request *srp, unsigned char *cmd)
1727{
1728 int res;
1729 struct request *rq;
1730 Sg_fd *sfp = srp->parentfp;
1731 sg_io_hdr_t *hp = &srp->header;
1732 int dxfer_len = (int) hp->dxfer_len;
1733 int dxfer_dir = hp->dxfer_direction;
1734 unsigned int iov_count = hp->iovec_count;
1735 Sg_scatter_hold *req_schp = &srp->data;
1736 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1737 struct request_queue *q = sfp->parentdp->device->request_queue;
1738 struct rq_map_data *md, map_data;
1739 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? ITER_SOURCE : ITER_DEST;
1740 struct scsi_cmnd *scmd;
1741
1742 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1743 "sg_start_req: dxfer_len=%d\n",
1744 dxfer_len));
1745
1746 /*
1747 * NOTE
1748 *
1749 * With scsi-mq enabled, there are a fixed number of preallocated
1750 * requests equal in number to shost->can_queue. If all of the
1751 * preallocated requests are already in use, then scsi_alloc_request()
1752 * will sleep until an active command completes, freeing up a request.
1753 * Although waiting in an asynchronous interface is less than ideal, we
1754 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
1755 * not expect an EWOULDBLOCK from this condition.
1756 */
1757 rq = scsi_alloc_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1758 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
1759 if (IS_ERR(rq))
1760 return PTR_ERR(rq);
1761 scmd = blk_mq_rq_to_pdu(rq);
1762
1763 if (hp->cmd_len > sizeof(scmd->cmnd)) {
1764 blk_mq_free_request(rq);
1765 return -EINVAL;
1766 }
1767
1768 memcpy(scmd->cmnd, cmd, hp->cmd_len);
1769 scmd->cmd_len = hp->cmd_len;
1770
1771 srp->rq = rq;
1772 rq->end_io_data = srp;
1773 scmd->allowed = SG_DEFAULT_RETRIES;
1774
1775 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1776 return 0;
1777
1778 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1779 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1780 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1781 md = NULL;
1782 else
1783 md = &map_data;
1784
1785 if (md) {
1786 mutex_lock(&sfp->f_mutex);
1787 if (dxfer_len <= rsv_schp->bufflen &&
1788 !sfp->res_in_use) {
1789 sfp->res_in_use = 1;
1790 sg_link_reserve(sfp, srp, dxfer_len);
1791 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1792 res = -EBUSY; /* sfp->res_in_use == 1 */
1793 if (dxfer_len > rsv_schp->bufflen)
1794 res = -ENOMEM;
1795 mutex_unlock(&sfp->f_mutex);
1796 return res;
1797 } else {
1798 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1799 if (res) {
1800 mutex_unlock(&sfp->f_mutex);
1801 return res;
1802 }
1803 }
1804 mutex_unlock(&sfp->f_mutex);
1805
1806 md->pages = req_schp->pages;
1807 md->page_order = req_schp->page_order;
1808 md->nr_entries = req_schp->k_use_sg;
1809 md->offset = 0;
1810 md->null_mapped = hp->dxferp ? 0 : 1;
1811 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1812 md->from_user = 1;
1813 else
1814 md->from_user = 0;
1815 }
1816
1817 res = blk_rq_map_user_io(rq, md, hp->dxferp, hp->dxfer_len,
1818 GFP_ATOMIC, iov_count, iov_count, 1, rw);
1819 if (!res) {
1820 srp->bio = rq->bio;
1821
1822 if (!md) {
1823 req_schp->dio_in_use = 1;
1824 hp->info |= SG_INFO_DIRECT_IO;
1825 }
1826 }
1827 return res;
1828}
1829
1830static int
1831sg_finish_rem_req(Sg_request *srp)
1832{
1833 int ret = 0;
1834
1835 Sg_fd *sfp = srp->parentfp;
1836 Sg_scatter_hold *req_schp = &srp->data;
1837
1838 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1839 "sg_finish_rem_req: res_used=%d\n",
1840 (int) srp->res_used));
1841 if (srp->bio)
1842 ret = blk_rq_unmap_user(srp->bio);
1843
1844 if (srp->rq)
1845 blk_mq_free_request(srp->rq);
1846
1847 if (srp->res_used)
1848 sg_unlink_reserve(sfp, srp);
1849 else
1850 sg_remove_scat(sfp, req_schp);
1851
1852 return ret;
1853}
1854
1855static int
1856sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1857{
1858 int sg_bufflen = tablesize * sizeof(struct page *);
1859 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1860
1861 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1862 if (!schp->pages)
1863 return -ENOMEM;
1864 schp->sglist_len = sg_bufflen;
1865 return tablesize; /* number of scat_gath elements allocated */
1866}
1867
1868static int
1869sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1870{
1871 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1872 int sg_tablesize = sfp->parentdp->sg_tablesize;
1873 int blk_size = buff_size, order;
1874 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
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 order = get_order(num);
1901retry:
1902 ret_sz = 1 << (PAGE_SHIFT + order);
1903
1904 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1905 k++, rem_sz -= ret_sz) {
1906
1907 num = (rem_sz > scatter_elem_sz_prev) ?
1908 scatter_elem_sz_prev : rem_sz;
1909
1910 schp->pages[k] = alloc_pages(gfp_mask, order);
1911 if (!schp->pages[k])
1912 goto out;
1913
1914 if (num == scatter_elem_sz_prev) {
1915 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1916 scatter_elem_sz = ret_sz;
1917 scatter_elem_sz_prev = ret_sz;
1918 }
1919 }
1920
1921 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1922 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1923 k, num, ret_sz));
1924 } /* end of for loop */
1925
1926 schp->page_order = order;
1927 schp->k_use_sg = k;
1928 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1929 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1930 k, rem_sz));
1931
1932 schp->bufflen = blk_size;
1933 if (rem_sz > 0) /* must have failed */
1934 return -ENOMEM;
1935 return 0;
1936out:
1937 for (i = 0; i < k; i++)
1938 __free_pages(schp->pages[i], order);
1939
1940 if (--order >= 0)
1941 goto retry;
1942
1943 return -ENOMEM;
1944}
1945
1946static void
1947sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1948{
1949 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1950 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1951 if (schp->pages && schp->sglist_len > 0) {
1952 if (!schp->dio_in_use) {
1953 int k;
1954
1955 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1956 SCSI_LOG_TIMEOUT(5,
1957 sg_printk(KERN_INFO, sfp->parentdp,
1958 "sg_remove_scat: k=%d, pg=0x%p\n",
1959 k, schp->pages[k]));
1960 __free_pages(schp->pages[k], schp->page_order);
1961 }
1962
1963 kfree(schp->pages);
1964 }
1965 }
1966 memset(schp, 0, sizeof (*schp));
1967}
1968
1969static int
1970sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1971{
1972 Sg_scatter_hold *schp = &srp->data;
1973 int k, num;
1974
1975 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1976 "sg_read_oxfer: num_read_xfer=%d\n",
1977 num_read_xfer));
1978 if ((!outp) || (num_read_xfer <= 0))
1979 return 0;
1980
1981 num = 1 << (PAGE_SHIFT + schp->page_order);
1982 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1983 if (num > num_read_xfer) {
1984 if (copy_to_user(outp, page_address(schp->pages[k]),
1985 num_read_xfer))
1986 return -EFAULT;
1987 break;
1988 } else {
1989 if (copy_to_user(outp, page_address(schp->pages[k]),
1990 num))
1991 return -EFAULT;
1992 num_read_xfer -= num;
1993 if (num_read_xfer <= 0)
1994 break;
1995 outp += num;
1996 }
1997 }
1998
1999 return 0;
2000}
2001
2002static void
2003sg_build_reserve(Sg_fd * sfp, int req_size)
2004{
2005 Sg_scatter_hold *schp = &sfp->reserve;
2006
2007 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2008 "sg_build_reserve: req_size=%d\n", req_size));
2009 do {
2010 if (req_size < PAGE_SIZE)
2011 req_size = PAGE_SIZE;
2012 if (0 == sg_build_indirect(schp, sfp, req_size))
2013 return;
2014 else
2015 sg_remove_scat(sfp, schp);
2016 req_size >>= 1; /* divide by 2 */
2017 } while (req_size > (PAGE_SIZE / 2));
2018}
2019
2020static void
2021sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2022{
2023 Sg_scatter_hold *req_schp = &srp->data;
2024 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2025 int k, num, rem;
2026
2027 srp->res_used = 1;
2028 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2029 "sg_link_reserve: size=%d\n", size));
2030 rem = size;
2031
2032 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2033 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2034 if (rem <= num) {
2035 req_schp->k_use_sg = k + 1;
2036 req_schp->sglist_len = rsv_schp->sglist_len;
2037 req_schp->pages = rsv_schp->pages;
2038
2039 req_schp->bufflen = size;
2040 req_schp->page_order = rsv_schp->page_order;
2041 break;
2042 } else
2043 rem -= num;
2044 }
2045
2046 if (k >= rsv_schp->k_use_sg)
2047 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2048 "sg_link_reserve: BAD size\n"));
2049}
2050
2051static void
2052sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2053{
2054 Sg_scatter_hold *req_schp = &srp->data;
2055
2056 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2057 "sg_unlink_reserve: req->k_use_sg=%d\n",
2058 (int) req_schp->k_use_sg));
2059 req_schp->k_use_sg = 0;
2060 req_schp->bufflen = 0;
2061 req_schp->pages = NULL;
2062 req_schp->page_order = 0;
2063 req_schp->sglist_len = 0;
2064 srp->res_used = 0;
2065 /* Called without mutex lock to avoid deadlock */
2066 sfp->res_in_use = 0;
2067}
2068
2069static Sg_request *
2070sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy)
2071{
2072 Sg_request *resp;
2073 unsigned long iflags;
2074
2075 *busy = false;
2076 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2077 list_for_each_entry(resp, &sfp->rq_list, entry) {
2078 /* look for requests that are not SG_IO owned */
2079 if ((!resp->sg_io_owned) &&
2080 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2081 switch (resp->done) {
2082 case 0: /* request active */
2083 *busy = true;
2084 break;
2085 case 1: /* request done; response ready to return */
2086 resp->done = 2; /* guard against other readers */
2087 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2088 return resp;
2089 case 2: /* response already being returned */
2090 break;
2091 }
2092 }
2093 }
2094 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2095 return NULL;
2096}
2097
2098/* always adds to end of list */
2099static Sg_request *
2100sg_add_request(Sg_fd * sfp)
2101{
2102 int k;
2103 unsigned long iflags;
2104 Sg_request *rp = sfp->req_arr;
2105
2106 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2107 if (!list_empty(&sfp->rq_list)) {
2108 if (!sfp->cmd_q)
2109 goto out_unlock;
2110
2111 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2112 if (!rp->parentfp)
2113 break;
2114 }
2115 if (k >= SG_MAX_QUEUE)
2116 goto out_unlock;
2117 }
2118 memset(rp, 0, sizeof (Sg_request));
2119 rp->parentfp = sfp;
2120 rp->header.duration = jiffies_to_msecs(jiffies);
2121 list_add_tail(&rp->entry, &sfp->rq_list);
2122 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2123 return rp;
2124out_unlock:
2125 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2126 return NULL;
2127}
2128
2129/* Return of 1 for found; 0 for not found */
2130static int
2131sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2132{
2133 unsigned long iflags;
2134 int res = 0;
2135
2136 if (!sfp || !srp || list_empty(&sfp->rq_list))
2137 return res;
2138 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2139 if (!list_empty(&srp->entry)) {
2140 list_del(&srp->entry);
2141 srp->parentfp = NULL;
2142 res = 1;
2143 }
2144 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2145
2146 /*
2147 * If the device is detaching, wakeup any readers in case we just
2148 * removed the last response, which would leave nothing for them to
2149 * return other than -ENODEV.
2150 */
2151 if (unlikely(atomic_read(&sfp->parentdp->detaching)))
2152 wake_up_interruptible_all(&sfp->read_wait);
2153
2154 return res;
2155}
2156
2157static Sg_fd *
2158sg_add_sfp(Sg_device * sdp)
2159{
2160 Sg_fd *sfp;
2161 unsigned long iflags;
2162 int bufflen;
2163
2164 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2165 if (!sfp)
2166 return ERR_PTR(-ENOMEM);
2167
2168 init_waitqueue_head(&sfp->read_wait);
2169 rwlock_init(&sfp->rq_list_lock);
2170 INIT_LIST_HEAD(&sfp->rq_list);
2171 kref_init(&sfp->f_ref);
2172 mutex_init(&sfp->f_mutex);
2173 sfp->timeout = SG_DEFAULT_TIMEOUT;
2174 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2175 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2176 sfp->cmd_q = SG_DEF_COMMAND_Q;
2177 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2178 sfp->parentdp = sdp;
2179 write_lock_irqsave(&sdp->sfd_lock, iflags);
2180 if (atomic_read(&sdp->detaching)) {
2181 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2182 kfree(sfp);
2183 return ERR_PTR(-ENODEV);
2184 }
2185 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2186 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2187 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2188 "sg_add_sfp: sfp=0x%p\n", sfp));
2189 if (unlikely(sg_big_buff != def_reserved_size))
2190 sg_big_buff = def_reserved_size;
2191
2192 bufflen = min_t(int, sg_big_buff,
2193 max_sectors_bytes(sdp->device->request_queue));
2194 sg_build_reserve(sfp, bufflen);
2195 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2196 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2197 sfp->reserve.bufflen,
2198 sfp->reserve.k_use_sg));
2199
2200 kref_get(&sdp->d_ref);
2201 __module_get(THIS_MODULE);
2202 return sfp;
2203}
2204
2205static void
2206sg_remove_sfp_usercontext(struct work_struct *work)
2207{
2208 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2209 struct sg_device *sdp = sfp->parentdp;
2210 Sg_request *srp;
2211 unsigned long iflags;
2212
2213 /* Cleanup any responses which were never read(). */
2214 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2215 while (!list_empty(&sfp->rq_list)) {
2216 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2217 sg_finish_rem_req(srp);
2218 list_del(&srp->entry);
2219 srp->parentfp = NULL;
2220 }
2221 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2222
2223 if (sfp->reserve.bufflen > 0) {
2224 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2225 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2226 (int) sfp->reserve.bufflen,
2227 (int) sfp->reserve.k_use_sg));
2228 sg_remove_scat(sfp, &sfp->reserve);
2229 }
2230
2231 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2232 "sg_remove_sfp: sfp=0x%p\n", sfp));
2233 kfree(sfp);
2234
2235 scsi_device_put(sdp->device);
2236 kref_put(&sdp->d_ref, sg_device_destroy);
2237 module_put(THIS_MODULE);
2238}
2239
2240static void
2241sg_remove_sfp(struct kref *kref)
2242{
2243 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2244 struct sg_device *sdp = sfp->parentdp;
2245 unsigned long iflags;
2246
2247 write_lock_irqsave(&sdp->sfd_lock, iflags);
2248 list_del(&sfp->sfd_siblings);
2249 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2250
2251 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2252 schedule_work(&sfp->ew.work);
2253}
2254
2255#ifdef CONFIG_SCSI_PROC_FS
2256static int
2257sg_idr_max_id(int id, void *p, void *data)
2258{
2259 int *k = data;
2260
2261 if (*k < id)
2262 *k = id;
2263
2264 return 0;
2265}
2266
2267static int
2268sg_last_dev(void)
2269{
2270 int k = -1;
2271 unsigned long iflags;
2272
2273 read_lock_irqsave(&sg_index_lock, iflags);
2274 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2275 read_unlock_irqrestore(&sg_index_lock, iflags);
2276 return k + 1; /* origin 1 */
2277}
2278#endif
2279
2280/* must be called with sg_index_lock held */
2281static Sg_device *sg_lookup_dev(int dev)
2282{
2283 return idr_find(&sg_index_idr, dev);
2284}
2285
2286static Sg_device *
2287sg_get_dev(int dev)
2288{
2289 struct sg_device *sdp;
2290 unsigned long flags;
2291
2292 read_lock_irqsave(&sg_index_lock, flags);
2293 sdp = sg_lookup_dev(dev);
2294 if (!sdp)
2295 sdp = ERR_PTR(-ENXIO);
2296 else if (atomic_read(&sdp->detaching)) {
2297 /* If sdp->detaching, then the refcount may already be 0, in
2298 * which case it would be a bug to do kref_get().
2299 */
2300 sdp = ERR_PTR(-ENODEV);
2301 } else
2302 kref_get(&sdp->d_ref);
2303 read_unlock_irqrestore(&sg_index_lock, flags);
2304
2305 return sdp;
2306}
2307
2308#ifdef CONFIG_SCSI_PROC_FS
2309static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2310
2311static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2312static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2313 size_t count, loff_t *off);
2314static const struct proc_ops adio_proc_ops = {
2315 .proc_open = sg_proc_single_open_adio,
2316 .proc_read = seq_read,
2317 .proc_lseek = seq_lseek,
2318 .proc_write = sg_proc_write_adio,
2319 .proc_release = single_release,
2320};
2321
2322static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2323static ssize_t sg_proc_write_dressz(struct file *filp,
2324 const char __user *buffer, size_t count, loff_t *off);
2325static const struct proc_ops dressz_proc_ops = {
2326 .proc_open = sg_proc_single_open_dressz,
2327 .proc_read = seq_read,
2328 .proc_lseek = seq_lseek,
2329 .proc_write = sg_proc_write_dressz,
2330 .proc_release = single_release,
2331};
2332
2333static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2334static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2335static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2336static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2337static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2338static void dev_seq_stop(struct seq_file *s, void *v);
2339static const struct seq_operations dev_seq_ops = {
2340 .start = dev_seq_start,
2341 .next = dev_seq_next,
2342 .stop = dev_seq_stop,
2343 .show = sg_proc_seq_show_dev,
2344};
2345
2346static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2347static const struct seq_operations devstrs_seq_ops = {
2348 .start = dev_seq_start,
2349 .next = dev_seq_next,
2350 .stop = dev_seq_stop,
2351 .show = sg_proc_seq_show_devstrs,
2352};
2353
2354static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2355static const struct seq_operations debug_seq_ops = {
2356 .start = dev_seq_start,
2357 .next = dev_seq_next,
2358 .stop = dev_seq_stop,
2359 .show = sg_proc_seq_show_debug,
2360};
2361
2362static int
2363sg_proc_init(void)
2364{
2365 struct proc_dir_entry *p;
2366
2367 p = proc_mkdir("scsi/sg", NULL);
2368 if (!p)
2369 return 1;
2370
2371 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_proc_ops);
2372 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);
2373 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_proc_ops);
2374 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr);
2375 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops);
2376 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops);
2377 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version);
2378 return 0;
2379}
2380
2381
2382static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2383{
2384 seq_printf(s, "%d\n", *((int *)s->private));
2385 return 0;
2386}
2387
2388static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2389{
2390 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2391}
2392
2393static ssize_t
2394sg_proc_write_adio(struct file *filp, const char __user *buffer,
2395 size_t count, loff_t *off)
2396{
2397 int err;
2398 unsigned long num;
2399
2400 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2401 return -EACCES;
2402 err = kstrtoul_from_user(buffer, count, 0, &num);
2403 if (err)
2404 return err;
2405 sg_allow_dio = num ? 1 : 0;
2406 return count;
2407}
2408
2409static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2410{
2411 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2412}
2413
2414static ssize_t
2415sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2416 size_t count, loff_t *off)
2417{
2418 int err;
2419 unsigned long k = ULONG_MAX;
2420
2421 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2422 return -EACCES;
2423
2424 err = kstrtoul_from_user(buffer, count, 0, &k);
2425 if (err)
2426 return err;
2427 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2428 sg_big_buff = k;
2429 return count;
2430 }
2431 return -ERANGE;
2432}
2433
2434static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2435{
2436 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2437 sg_version_date);
2438 return 0;
2439}
2440
2441static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2442{
2443 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2444 return 0;
2445}
2446
2447struct sg_proc_deviter {
2448 loff_t index;
2449 size_t max;
2450};
2451
2452static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2453{
2454 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2455
2456 s->private = it;
2457 if (! it)
2458 return NULL;
2459
2460 it->index = *pos;
2461 it->max = sg_last_dev();
2462 if (it->index >= it->max)
2463 return NULL;
2464 return it;
2465}
2466
2467static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2468{
2469 struct sg_proc_deviter * it = s->private;
2470
2471 *pos = ++it->index;
2472 return (it->index < it->max) ? it : NULL;
2473}
2474
2475static void dev_seq_stop(struct seq_file *s, void *v)
2476{
2477 kfree(s->private);
2478}
2479
2480static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2481{
2482 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2483 Sg_device *sdp;
2484 struct scsi_device *scsidp;
2485 unsigned long iflags;
2486
2487 read_lock_irqsave(&sg_index_lock, iflags);
2488 sdp = it ? sg_lookup_dev(it->index) : NULL;
2489 if ((NULL == sdp) || (NULL == sdp->device) ||
2490 (atomic_read(&sdp->detaching)))
2491 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2492 else {
2493 scsidp = sdp->device;
2494 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2495 scsidp->host->host_no, scsidp->channel,
2496 scsidp->id, scsidp->lun, (int) scsidp->type,
2497 1,
2498 (int) scsidp->queue_depth,
2499 (int) scsi_device_busy(scsidp),
2500 (int) scsi_device_online(scsidp));
2501 }
2502 read_unlock_irqrestore(&sg_index_lock, iflags);
2503 return 0;
2504}
2505
2506static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2507{
2508 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2509 Sg_device *sdp;
2510 struct scsi_device *scsidp;
2511 unsigned long iflags;
2512
2513 read_lock_irqsave(&sg_index_lock, iflags);
2514 sdp = it ? sg_lookup_dev(it->index) : NULL;
2515 scsidp = sdp ? sdp->device : NULL;
2516 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2517 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2518 scsidp->vendor, scsidp->model, scsidp->rev);
2519 else
2520 seq_puts(s, "<no active device>\n");
2521 read_unlock_irqrestore(&sg_index_lock, iflags);
2522 return 0;
2523}
2524
2525/* must be called while holding sg_index_lock */
2526static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2527{
2528 int k, new_interface, blen, usg;
2529 Sg_request *srp;
2530 Sg_fd *fp;
2531 const sg_io_hdr_t *hp;
2532 const char * cp;
2533 unsigned int ms;
2534
2535 k = 0;
2536 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2537 k++;
2538 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2539 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2540 "(res)sgat=%d low_dma=%d\n", k,
2541 jiffies_to_msecs(fp->timeout),
2542 fp->reserve.bufflen,
2543 (int) fp->reserve.k_use_sg, 0);
2544 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2545 (int) fp->cmd_q, (int) fp->force_packid,
2546 (int) fp->keep_orphan);
2547 list_for_each_entry(srp, &fp->rq_list, entry) {
2548 hp = &srp->header;
2549 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2550 if (srp->res_used) {
2551 if (new_interface &&
2552 (SG_FLAG_MMAP_IO & hp->flags))
2553 cp = " mmap>> ";
2554 else
2555 cp = " rb>> ";
2556 } else {
2557 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2558 cp = " dio>> ";
2559 else
2560 cp = " ";
2561 }
2562 seq_puts(s, cp);
2563 blen = srp->data.bufflen;
2564 usg = srp->data.k_use_sg;
2565 seq_puts(s, srp->done ?
2566 ((1 == srp->done) ? "rcv:" : "fin:")
2567 : "act:");
2568 seq_printf(s, " id=%d blen=%d",
2569 srp->header.pack_id, blen);
2570 if (srp->done)
2571 seq_printf(s, " dur=%d", hp->duration);
2572 else {
2573 ms = jiffies_to_msecs(jiffies);
2574 seq_printf(s, " t_o/elap=%d/%d",
2575 (new_interface ? hp->timeout :
2576 jiffies_to_msecs(fp->timeout)),
2577 (ms > hp->duration ? ms - hp->duration : 0));
2578 }
2579 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2580 (int) srp->data.cmd_opcode);
2581 }
2582 if (list_empty(&fp->rq_list))
2583 seq_puts(s, " No requests active\n");
2584 read_unlock(&fp->rq_list_lock);
2585 }
2586}
2587
2588static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2589{
2590 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2591 Sg_device *sdp;
2592 unsigned long iflags;
2593
2594 if (it && (0 == it->index))
2595 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2596 (int)it->max, sg_big_buff);
2597
2598 read_lock_irqsave(&sg_index_lock, iflags);
2599 sdp = it ? sg_lookup_dev(it->index) : NULL;
2600 if (NULL == sdp)
2601 goto skip;
2602 read_lock(&sdp->sfd_lock);
2603 if (!list_empty(&sdp->sfds)) {
2604 seq_printf(s, " >>> device=%s ", sdp->name);
2605 if (atomic_read(&sdp->detaching))
2606 seq_puts(s, "detaching pending close ");
2607 else if (sdp->device) {
2608 struct scsi_device *scsidp = sdp->device;
2609
2610 seq_printf(s, "%d:%d:%d:%llu em=%d",
2611 scsidp->host->host_no,
2612 scsidp->channel, scsidp->id,
2613 scsidp->lun,
2614 scsidp->host->hostt->emulated);
2615 }
2616 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2617 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2618 sg_proc_debug_helper(s, sdp);
2619 }
2620 read_unlock(&sdp->sfd_lock);
2621skip:
2622 read_unlock_irqrestore(&sg_index_lock, iflags);
2623 return 0;
2624}
2625
2626#endif /* CONFIG_SCSI_PROC_FS */
2627
2628module_init(init_sg);
2629module_exit(exit_sg);
1/*
2 * History:
3 * Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
4 * to allow user process control of SCSI devices.
5 * Development Sponsored by Killy Corp. NY NY
6 *
7 * Original driver (sg.c):
8 * Copyright (C) 1992 Lawrence Foard
9 * Version 2 and 3 extensions to driver:
10 * Copyright (C) 1998 - 2014 Douglas Gilbert
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2, or (at your option)
15 * any later version.
16 *
17 */
18
19static int sg_version_num = 30536; /* 2 digits for each component */
20#define SG_VERSION_STR "3.5.36"
21
22/*
23 * D. P. Gilbert (dgilbert@interlog.com), notes:
24 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
25 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING
26 * (otherwise the macros compile to empty statements).
27 *
28 */
29#include <linux/module.h>
30
31#include <linux/fs.h>
32#include <linux/kernel.h>
33#include <linux/sched.h>
34#include <linux/string.h>
35#include <linux/mm.h>
36#include <linux/errno.h>
37#include <linux/mtio.h>
38#include <linux/ioctl.h>
39#include <linux/slab.h>
40#include <linux/fcntl.h>
41#include <linux/init.h>
42#include <linux/poll.h>
43#include <linux/moduleparam.h>
44#include <linux/cdev.h>
45#include <linux/idr.h>
46#include <linux/seq_file.h>
47#include <linux/blkdev.h>
48#include <linux/delay.h>
49#include <linux/blktrace_api.h>
50#include <linux/mutex.h>
51#include <linux/atomic.h>
52#include <linux/ratelimit.h>
53#include <linux/uio.h>
54
55#include "scsi.h"
56#include <scsi/scsi_dbg.h>
57#include <scsi/scsi_host.h>
58#include <scsi/scsi_driver.h>
59#include <scsi/scsi_ioctl.h>
60#include <scsi/sg.h>
61
62#include "scsi_logging.h"
63
64#ifdef CONFIG_SCSI_PROC_FS
65#include <linux/proc_fs.h>
66static char *sg_version_date = "20140603";
67
68static int sg_proc_init(void);
69static void sg_proc_cleanup(void);
70#endif
71
72#define SG_ALLOW_DIO_DEF 0
73
74#define SG_MAX_DEVS 32768
75
76/* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type
77 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater
78 * than 16 bytes are "variable length" whose length is a multiple of 4
79 */
80#define SG_MAX_CDB_SIZE 252
81
82#define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
83
84int sg_big_buff = SG_DEF_RESERVED_SIZE;
85/* N.B. This variable is readable and writeable via
86 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
87 of this size (or less if there is not enough memory) will be reserved
88 for use by this file descriptor. [Deprecated usage: this variable is also
89 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
90 the kernel (i.e. it is not a module).] */
91static int def_reserved_size = -1; /* picks up init parameter */
92static int sg_allow_dio = SG_ALLOW_DIO_DEF;
93
94static int scatter_elem_sz = SG_SCATTER_SZ;
95static int scatter_elem_sz_prev = SG_SCATTER_SZ;
96
97#define SG_SECTOR_SZ 512
98
99static int sg_add_device(struct device *, struct class_interface *);
100static void sg_remove_device(struct device *, struct class_interface *);
101
102static DEFINE_IDR(sg_index_idr);
103static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
104 file descriptor list for device */
105
106static struct class_interface sg_interface = {
107 .add_dev = sg_add_device,
108 .remove_dev = sg_remove_device,
109};
110
111typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
112 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
113 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
114 unsigned bufflen; /* Size of (aggregate) data buffer */
115 struct page **pages;
116 int page_order;
117 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
118 unsigned char cmd_opcode; /* first byte of command */
119} Sg_scatter_hold;
120
121struct sg_device; /* forward declarations */
122struct sg_fd;
123
124typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
125 struct list_head entry; /* list entry */
126 struct sg_fd *parentfp; /* NULL -> not in use */
127 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
128 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
129 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
130 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
131 char orphan; /* 1 -> drop on sight, 0 -> normal */
132 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
133 /* done protected by rq_list_lock */
134 char done; /* 0->before bh, 1->before read, 2->read */
135 struct request *rq;
136 struct bio *bio;
137 struct execute_work ew;
138} Sg_request;
139
140typedef struct sg_fd { /* holds the state of a file descriptor */
141 struct list_head sfd_siblings; /* protected by device's sfd_lock */
142 struct sg_device *parentdp; /* owning device */
143 wait_queue_head_t read_wait; /* queue read until command done */
144 rwlock_t rq_list_lock; /* protect access to list in req_arr */
145 struct mutex f_mutex; /* protect against changes in this fd */
146 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
147 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
148 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
149 struct list_head rq_list; /* head of request list */
150 struct fasync_struct *async_qp; /* used by asynchronous notification */
151 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
152 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
153 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
154 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
155 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
156 char mmap_called; /* 0 -> mmap() never called on this fd */
157 char res_in_use; /* 1 -> 'reserve' array in use */
158 struct kref f_ref;
159 struct execute_work ew;
160} Sg_fd;
161
162typedef struct sg_device { /* holds the state of each scsi generic device */
163 struct scsi_device *device;
164 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */
165 struct mutex open_rel_lock; /* held when in open() or release() */
166 int sg_tablesize; /* adapter's max scatter-gather table size */
167 u32 index; /* device index number */
168 struct list_head sfds;
169 rwlock_t sfd_lock; /* protect access to sfd list */
170 atomic_t detaching; /* 0->device usable, 1->device detaching */
171 bool exclude; /* 1->open(O_EXCL) succeeded and is active */
172 int open_cnt; /* count of opens (perhaps < num(sfds) ) */
173 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
174 struct gendisk *disk;
175 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
176 struct kref d_ref;
177} Sg_device;
178
179/* tasklet or soft irq callback */
180static void sg_rq_end_io(struct request *rq, blk_status_t status);
181static int sg_start_req(Sg_request *srp, unsigned char *cmd);
182static int sg_finish_rem_req(Sg_request * srp);
183static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
184static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
185 Sg_request * srp);
186static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
187 const char __user *buf, size_t count, int blocking,
188 int read_only, int sg_io_owned, Sg_request **o_srp);
189static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
190 unsigned char *cmnd, int timeout, int blocking);
191static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
192static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
193static void sg_build_reserve(Sg_fd * sfp, int req_size);
194static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
195static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
196static Sg_fd *sg_add_sfp(Sg_device * sdp);
197static void sg_remove_sfp(struct kref *);
198static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
199static Sg_request *sg_add_request(Sg_fd * sfp);
200static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
201static Sg_device *sg_get_dev(int dev);
202static void sg_device_destroy(struct kref *kref);
203
204#define SZ_SG_HEADER sizeof(struct sg_header)
205#define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
206#define SZ_SG_IOVEC sizeof(sg_iovec_t)
207#define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
208
209#define sg_printk(prefix, sdp, fmt, a...) \
210 sdev_prefix_printk(prefix, (sdp)->device, \
211 (sdp)->disk->disk_name, fmt, ##a)
212
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);
221}
222
223static int
224open_wait(Sg_device *sdp, int flags)
225{
226 int retval = 0;
227
228 if (flags & O_EXCL) {
229 while (sdp->open_cnt > 0) {
230 mutex_unlock(&sdp->open_rel_lock);
231 retval = wait_event_interruptible(sdp->open_wait,
232 (atomic_read(&sdp->detaching) ||
233 !sdp->open_cnt));
234 mutex_lock(&sdp->open_rel_lock);
235
236 if (retval) /* -ERESTARTSYS */
237 return retval;
238 if (atomic_read(&sdp->detaching))
239 return -ENODEV;
240 }
241 } else {
242 while (sdp->exclude) {
243 mutex_unlock(&sdp->open_rel_lock);
244 retval = wait_event_interruptible(sdp->open_wait,
245 (atomic_read(&sdp->detaching) ||
246 !sdp->exclude));
247 mutex_lock(&sdp->open_rel_lock);
248
249 if (retval) /* -ERESTARTSYS */
250 return retval;
251 if (atomic_read(&sdp->detaching))
252 return -ENODEV;
253 }
254 }
255
256 return retval;
257}
258
259/* Returns 0 on success, else a negated errno value */
260static int
261sg_open(struct inode *inode, struct file *filp)
262{
263 int dev = iminor(inode);
264 int flags = filp->f_flags;
265 struct request_queue *q;
266 Sg_device *sdp;
267 Sg_fd *sfp;
268 int retval;
269
270 nonseekable_open(inode, filp);
271 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
272 return -EPERM; /* Can't lock it with read only access */
273 sdp = sg_get_dev(dev);
274 if (IS_ERR(sdp))
275 return PTR_ERR(sdp);
276
277 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
278 "sg_open: flags=0x%x\n", flags));
279
280 /* This driver's module count bumped by fops_get in <linux/fs.h> */
281 /* Prevent the device driver from vanishing while we sleep */
282 retval = scsi_device_get(sdp->device);
283 if (retval)
284 goto sg_put;
285
286 retval = scsi_autopm_get_device(sdp->device);
287 if (retval)
288 goto sdp_put;
289
290 /* scsi_block_when_processing_errors() may block so bypass
291 * check if O_NONBLOCK. Permits SCSI commands to be issued
292 * during error recovery. Tread carefully. */
293 if (!((flags & O_NONBLOCK) ||
294 scsi_block_when_processing_errors(sdp->device))) {
295 retval = -ENXIO;
296 /* we are in error recovery for this device */
297 goto error_out;
298 }
299
300 mutex_lock(&sdp->open_rel_lock);
301 if (flags & O_NONBLOCK) {
302 if (flags & O_EXCL) {
303 if (sdp->open_cnt > 0) {
304 retval = -EBUSY;
305 goto error_mutex_locked;
306 }
307 } else {
308 if (sdp->exclude) {
309 retval = -EBUSY;
310 goto error_mutex_locked;
311 }
312 }
313 } else {
314 retval = open_wait(sdp, flags);
315 if (retval) /* -ERESTARTSYS or -ENODEV */
316 goto error_mutex_locked;
317 }
318
319 /* N.B. at this point we are holding the open_rel_lock */
320 if (flags & O_EXCL)
321 sdp->exclude = true;
322
323 if (sdp->open_cnt < 1) { /* no existing opens */
324 sdp->sgdebug = 0;
325 q = sdp->device->request_queue;
326 sdp->sg_tablesize = queue_max_segments(q);
327 }
328 sfp = sg_add_sfp(sdp);
329 if (IS_ERR(sfp)) {
330 retval = PTR_ERR(sfp);
331 goto out_undo;
332 }
333
334 filp->private_data = sfp;
335 sdp->open_cnt++;
336 mutex_unlock(&sdp->open_rel_lock);
337
338 retval = 0;
339sg_put:
340 kref_put(&sdp->d_ref, sg_device_destroy);
341 return retval;
342
343out_undo:
344 if (flags & O_EXCL) {
345 sdp->exclude = false; /* undo if error */
346 wake_up_interruptible(&sdp->open_wait);
347 }
348error_mutex_locked:
349 mutex_unlock(&sdp->open_rel_lock);
350error_out:
351 scsi_autopm_put_device(sdp->device);
352sdp_put:
353 scsi_device_put(sdp->device);
354 goto sg_put;
355}
356
357/* Release resources associated with a successful sg_open()
358 * Returns 0 on success, else a negated errno value */
359static int
360sg_release(struct inode *inode, struct file *filp)
361{
362 Sg_device *sdp;
363 Sg_fd *sfp;
364
365 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
366 return -ENXIO;
367 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
368
369 mutex_lock(&sdp->open_rel_lock);
370 scsi_autopm_put_device(sdp->device);
371 kref_put(&sfp->f_ref, sg_remove_sfp);
372 sdp->open_cnt--;
373
374 /* possibly many open()s waiting on exlude clearing, start many;
375 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
376 if (sdp->exclude) {
377 sdp->exclude = false;
378 wake_up_interruptible_all(&sdp->open_wait);
379 } else if (0 == sdp->open_cnt) {
380 wake_up_interruptible(&sdp->open_wait);
381 }
382 mutex_unlock(&sdp->open_rel_lock);
383 return 0;
384}
385
386static ssize_t
387sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
388{
389 Sg_device *sdp;
390 Sg_fd *sfp;
391 Sg_request *srp;
392 int req_pack_id = -1;
393 sg_io_hdr_t *hp;
394 struct sg_header *old_hdr = NULL;
395 int retval = 0;
396
397 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
398 return -ENXIO;
399 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
400 "sg_read: count=%d\n", (int) count));
401
402 if (!access_ok(VERIFY_WRITE, buf, count))
403 return -EFAULT;
404 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
405 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
406 if (!old_hdr)
407 return -ENOMEM;
408 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
409 retval = -EFAULT;
410 goto free_old_hdr;
411 }
412 if (old_hdr->reply_len < 0) {
413 if (count >= SZ_SG_IO_HDR) {
414 sg_io_hdr_t *new_hdr;
415 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
416 if (!new_hdr) {
417 retval = -ENOMEM;
418 goto free_old_hdr;
419 }
420 retval =__copy_from_user
421 (new_hdr, buf, SZ_SG_IO_HDR);
422 req_pack_id = new_hdr->pack_id;
423 kfree(new_hdr);
424 if (retval) {
425 retval = -EFAULT;
426 goto free_old_hdr;
427 }
428 }
429 } else
430 req_pack_id = old_hdr->pack_id;
431 }
432 srp = sg_get_rq_mark(sfp, req_pack_id);
433 if (!srp) { /* now wait on packet to arrive */
434 if (atomic_read(&sdp->detaching)) {
435 retval = -ENODEV;
436 goto free_old_hdr;
437 }
438 if (filp->f_flags & O_NONBLOCK) {
439 retval = -EAGAIN;
440 goto free_old_hdr;
441 }
442 retval = wait_event_interruptible(sfp->read_wait,
443 (atomic_read(&sdp->detaching) ||
444 (srp = sg_get_rq_mark(sfp, req_pack_id))));
445 if (atomic_read(&sdp->detaching)) {
446 retval = -ENODEV;
447 goto free_old_hdr;
448 }
449 if (retval) {
450 /* -ERESTARTSYS as signal hit process */
451 goto free_old_hdr;
452 }
453 }
454 if (srp->header.interface_id != '\0') {
455 retval = sg_new_read(sfp, buf, count, srp);
456 goto free_old_hdr;
457 }
458
459 hp = &srp->header;
460 if (old_hdr == NULL) {
461 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
462 if (! old_hdr) {
463 retval = -ENOMEM;
464 goto free_old_hdr;
465 }
466 }
467 memset(old_hdr, 0, SZ_SG_HEADER);
468 old_hdr->reply_len = (int) hp->timeout;
469 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
470 old_hdr->pack_id = hp->pack_id;
471 old_hdr->twelve_byte =
472 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
473 old_hdr->target_status = hp->masked_status;
474 old_hdr->host_status = hp->host_status;
475 old_hdr->driver_status = hp->driver_status;
476 if ((CHECK_CONDITION & hp->masked_status) ||
477 (DRIVER_SENSE & hp->driver_status))
478 memcpy(old_hdr->sense_buffer, srp->sense_b,
479 sizeof (old_hdr->sense_buffer));
480 switch (hp->host_status) {
481 /* This setup of 'result' is for backward compatibility and is best
482 ignored by the user who should use target, host + driver status */
483 case DID_OK:
484 case DID_PASSTHROUGH:
485 case DID_SOFT_ERROR:
486 old_hdr->result = 0;
487 break;
488 case DID_NO_CONNECT:
489 case DID_BUS_BUSY:
490 case DID_TIME_OUT:
491 old_hdr->result = EBUSY;
492 break;
493 case DID_BAD_TARGET:
494 case DID_ABORT:
495 case DID_PARITY:
496 case DID_RESET:
497 case DID_BAD_INTR:
498 old_hdr->result = EIO;
499 break;
500 case DID_ERROR:
501 old_hdr->result = (srp->sense_b[0] == 0 &&
502 hp->masked_status == GOOD) ? 0 : EIO;
503 break;
504 default:
505 old_hdr->result = EIO;
506 break;
507 }
508
509 /* Now copy the result back to the user buffer. */
510 if (count >= SZ_SG_HEADER) {
511 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
512 retval = -EFAULT;
513 goto free_old_hdr;
514 }
515 buf += SZ_SG_HEADER;
516 if (count > old_hdr->reply_len)
517 count = old_hdr->reply_len;
518 if (count > SZ_SG_HEADER) {
519 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
520 retval = -EFAULT;
521 goto free_old_hdr;
522 }
523 }
524 } else
525 count = (old_hdr->result == 0) ? 0 : -EIO;
526 sg_finish_rem_req(srp);
527 sg_remove_request(sfp, srp);
528 retval = count;
529free_old_hdr:
530 kfree(old_hdr);
531 return retval;
532}
533
534static ssize_t
535sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
536{
537 sg_io_hdr_t *hp = &srp->header;
538 int err = 0, err2;
539 int len;
540
541 if (count < SZ_SG_IO_HDR) {
542 err = -EINVAL;
543 goto err_out;
544 }
545 hp->sb_len_wr = 0;
546 if ((hp->mx_sb_len > 0) && hp->sbp) {
547 if ((CHECK_CONDITION & hp->masked_status) ||
548 (DRIVER_SENSE & hp->driver_status)) {
549 int sb_len = SCSI_SENSE_BUFFERSIZE;
550 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
551 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
552 len = (len > sb_len) ? sb_len : len;
553 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
554 err = -EFAULT;
555 goto err_out;
556 }
557 hp->sb_len_wr = len;
558 }
559 }
560 if (hp->masked_status || hp->host_status || hp->driver_status)
561 hp->info |= SG_INFO_CHECK;
562 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
563 err = -EFAULT;
564 goto err_out;
565 }
566err_out:
567 err2 = sg_finish_rem_req(srp);
568 sg_remove_request(sfp, srp);
569 return err ? : err2 ? : count;
570}
571
572static ssize_t
573sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
574{
575 int mxsize, cmd_size, k;
576 int input_size, blocking;
577 unsigned char opcode;
578 Sg_device *sdp;
579 Sg_fd *sfp;
580 Sg_request *srp;
581 struct sg_header old_hdr;
582 sg_io_hdr_t *hp;
583 unsigned char cmnd[SG_MAX_CDB_SIZE];
584
585 if (unlikely(uaccess_kernel()))
586 return -EINVAL;
587
588 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
589 return -ENXIO;
590 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
591 "sg_write: count=%d\n", (int) count));
592 if (atomic_read(&sdp->detaching))
593 return -ENODEV;
594 if (!((filp->f_flags & O_NONBLOCK) ||
595 scsi_block_when_processing_errors(sdp->device)))
596 return -ENXIO;
597
598 if (!access_ok(VERIFY_READ, buf, count))
599 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
600 if (count < SZ_SG_HEADER)
601 return -EIO;
602 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
603 return -EFAULT;
604 blocking = !(filp->f_flags & O_NONBLOCK);
605 if (old_hdr.reply_len < 0)
606 return sg_new_write(sfp, filp, buf, count,
607 blocking, 0, 0, NULL);
608 if (count < (SZ_SG_HEADER + 6))
609 return -EIO; /* The minimum scsi command length is 6 bytes. */
610
611 if (!(srp = sg_add_request(sfp))) {
612 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
613 "sg_write: queue full\n"));
614 return -EDOM;
615 }
616 buf += SZ_SG_HEADER;
617 __get_user(opcode, buf);
618 mutex_lock(&sfp->f_mutex);
619 if (sfp->next_cmd_len > 0) {
620 cmd_size = sfp->next_cmd_len;
621 sfp->next_cmd_len = 0; /* reset so only this write() effected */
622 } else {
623 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
624 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
625 cmd_size = 12;
626 }
627 mutex_unlock(&sfp->f_mutex);
628 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
629 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
630/* Determine buffer size. */
631 input_size = count - cmd_size;
632 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
633 mxsize -= SZ_SG_HEADER;
634 input_size -= SZ_SG_HEADER;
635 if (input_size < 0) {
636 sg_remove_request(sfp, srp);
637 return -EIO; /* User did not pass enough bytes for this command. */
638 }
639 hp = &srp->header;
640 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
641 hp->cmd_len = (unsigned char) cmd_size;
642 hp->iovec_count = 0;
643 hp->mx_sb_len = 0;
644 if (input_size > 0)
645 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
646 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
647 else
648 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
649 hp->dxfer_len = mxsize;
650 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
651 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
652 hp->dxferp = (char __user *)buf + cmd_size;
653 else
654 hp->dxferp = NULL;
655 hp->sbp = NULL;
656 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
657 hp->flags = input_size; /* structure abuse ... */
658 hp->pack_id = old_hdr.pack_id;
659 hp->usr_ptr = NULL;
660 if (__copy_from_user(cmnd, buf, cmd_size))
661 return -EFAULT;
662 /*
663 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
664 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
665 * is a non-zero input_size, so emit a warning.
666 */
667 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
668 printk_ratelimited(KERN_WARNING
669 "sg_write: data in/out %d/%d bytes "
670 "for SCSI command 0x%x-- guessing "
671 "data in;\n program %s not setting "
672 "count and/or reply_len properly\n",
673 old_hdr.reply_len - (int)SZ_SG_HEADER,
674 input_size, (unsigned int) cmnd[0],
675 current->comm);
676 }
677 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
678 return (k < 0) ? k : count;
679}
680
681static ssize_t
682sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
683 size_t count, int blocking, int read_only, int sg_io_owned,
684 Sg_request **o_srp)
685{
686 int k;
687 Sg_request *srp;
688 sg_io_hdr_t *hp;
689 unsigned char cmnd[SG_MAX_CDB_SIZE];
690 int timeout;
691 unsigned long ul_timeout;
692
693 if (count < SZ_SG_IO_HDR)
694 return -EINVAL;
695 if (!access_ok(VERIFY_READ, buf, count))
696 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
697
698 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
699 if (!(srp = sg_add_request(sfp))) {
700 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
701 "sg_new_write: queue full\n"));
702 return -EDOM;
703 }
704 srp->sg_io_owned = sg_io_owned;
705 hp = &srp->header;
706 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
707 sg_remove_request(sfp, srp);
708 return -EFAULT;
709 }
710 if (hp->interface_id != 'S') {
711 sg_remove_request(sfp, srp);
712 return -ENOSYS;
713 }
714 if (hp->flags & SG_FLAG_MMAP_IO) {
715 if (hp->dxfer_len > sfp->reserve.bufflen) {
716 sg_remove_request(sfp, srp);
717 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
718 }
719 if (hp->flags & SG_FLAG_DIRECT_IO) {
720 sg_remove_request(sfp, srp);
721 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
722 }
723 if (sfp->res_in_use) {
724 sg_remove_request(sfp, srp);
725 return -EBUSY; /* reserve buffer already being used */
726 }
727 }
728 ul_timeout = msecs_to_jiffies(srp->header.timeout);
729 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
730 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
731 sg_remove_request(sfp, srp);
732 return -EMSGSIZE;
733 }
734 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
735 sg_remove_request(sfp, srp);
736 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
737 }
738 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
739 sg_remove_request(sfp, srp);
740 return -EFAULT;
741 }
742 if (read_only && sg_allow_access(file, cmnd)) {
743 sg_remove_request(sfp, srp);
744 return -EPERM;
745 }
746 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
747 if (k < 0)
748 return k;
749 if (o_srp)
750 *o_srp = srp;
751 return count;
752}
753
754static int
755sg_common_write(Sg_fd * sfp, Sg_request * srp,
756 unsigned char *cmnd, int timeout, int blocking)
757{
758 int k, at_head;
759 Sg_device *sdp = sfp->parentdp;
760 sg_io_hdr_t *hp = &srp->header;
761
762 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
763 hp->status = 0;
764 hp->masked_status = 0;
765 hp->msg_status = 0;
766 hp->info = 0;
767 hp->host_status = 0;
768 hp->driver_status = 0;
769 hp->resid = 0;
770 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
771 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
772 (int) cmnd[0], (int) hp->cmd_len));
773
774 if (hp->dxfer_len >= SZ_256M)
775 return -EINVAL;
776
777 k = sg_start_req(srp, cmnd);
778 if (k) {
779 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
780 "sg_common_write: start_req err=%d\n", k));
781 sg_finish_rem_req(srp);
782 sg_remove_request(sfp, srp);
783 return k; /* probably out of space --> ENOMEM */
784 }
785 if (atomic_read(&sdp->detaching)) {
786 if (srp->bio) {
787 scsi_req_free_cmd(scsi_req(srp->rq));
788 blk_end_request_all(srp->rq, BLK_STS_IOERR);
789 srp->rq = NULL;
790 }
791
792 sg_finish_rem_req(srp);
793 sg_remove_request(sfp, srp);
794 return -ENODEV;
795 }
796
797 hp->duration = jiffies_to_msecs(jiffies);
798 if (hp->interface_id != '\0' && /* v3 (or later) interface */
799 (SG_FLAG_Q_AT_TAIL & hp->flags))
800 at_head = 0;
801 else
802 at_head = 1;
803
804 srp->rq->timeout = timeout;
805 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
806 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
807 srp->rq, at_head, sg_rq_end_io);
808 return 0;
809}
810
811static int srp_done(Sg_fd *sfp, Sg_request *srp)
812{
813 unsigned long flags;
814 int ret;
815
816 read_lock_irqsave(&sfp->rq_list_lock, flags);
817 ret = srp->done;
818 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
819 return ret;
820}
821
822static int max_sectors_bytes(struct request_queue *q)
823{
824 unsigned int max_sectors = queue_max_sectors(q);
825
826 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
827
828 return max_sectors << 9;
829}
830
831static void
832sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
833{
834 Sg_request *srp;
835 int val;
836 unsigned int ms;
837
838 val = 0;
839 list_for_each_entry(srp, &sfp->rq_list, entry) {
840 if (val >= SG_MAX_QUEUE)
841 break;
842 rinfo[val].req_state = srp->done + 1;
843 rinfo[val].problem =
844 srp->header.masked_status &
845 srp->header.host_status &
846 srp->header.driver_status;
847 if (srp->done)
848 rinfo[val].duration =
849 srp->header.duration;
850 else {
851 ms = jiffies_to_msecs(jiffies);
852 rinfo[val].duration =
853 (ms > srp->header.duration) ?
854 (ms - srp->header.duration) : 0;
855 }
856 rinfo[val].orphan = srp->orphan;
857 rinfo[val].sg_io_owned = srp->sg_io_owned;
858 rinfo[val].pack_id = srp->header.pack_id;
859 rinfo[val].usr_ptr = srp->header.usr_ptr;
860 val++;
861 }
862}
863
864static long
865sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
866{
867 void __user *p = (void __user *)arg;
868 int __user *ip = p;
869 int result, val, read_only;
870 Sg_device *sdp;
871 Sg_fd *sfp;
872 Sg_request *srp;
873 unsigned long iflags;
874
875 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
876 return -ENXIO;
877
878 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
879 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
880 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
881
882 switch (cmd_in) {
883 case SG_IO:
884 if (atomic_read(&sdp->detaching))
885 return -ENODEV;
886 if (!scsi_block_when_processing_errors(sdp->device))
887 return -ENXIO;
888 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
889 return -EFAULT;
890 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
891 1, read_only, 1, &srp);
892 if (result < 0)
893 return result;
894 result = wait_event_interruptible(sfp->read_wait,
895 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
896 if (atomic_read(&sdp->detaching))
897 return -ENODEV;
898 write_lock_irq(&sfp->rq_list_lock);
899 if (srp->done) {
900 srp->done = 2;
901 write_unlock_irq(&sfp->rq_list_lock);
902 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
903 return (result < 0) ? result : 0;
904 }
905 srp->orphan = 1;
906 write_unlock_irq(&sfp->rq_list_lock);
907 return result; /* -ERESTARTSYS because signal hit process */
908 case SG_SET_TIMEOUT:
909 result = get_user(val, ip);
910 if (result)
911 return result;
912 if (val < 0)
913 return -EIO;
914 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
915 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
916 INT_MAX);
917 sfp->timeout_user = val;
918 sfp->timeout = mult_frac(val, HZ, USER_HZ);
919
920 return 0;
921 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
922 /* strange ..., for backward compatibility */
923 return sfp->timeout_user;
924 case SG_SET_FORCE_LOW_DMA:
925 /*
926 * N.B. This ioctl never worked properly, but failed to
927 * return an error value. So returning '0' to keep compability
928 * with legacy applications.
929 */
930 return 0;
931 case SG_GET_LOW_DMA:
932 return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
933 case SG_GET_SCSI_ID:
934 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
935 return -EFAULT;
936 else {
937 sg_scsi_id_t __user *sg_idp = p;
938
939 if (atomic_read(&sdp->detaching))
940 return -ENODEV;
941 __put_user((int) sdp->device->host->host_no,
942 &sg_idp->host_no);
943 __put_user((int) sdp->device->channel,
944 &sg_idp->channel);
945 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
946 __put_user((int) sdp->device->lun, &sg_idp->lun);
947 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
948 __put_user((short) sdp->device->host->cmd_per_lun,
949 &sg_idp->h_cmd_per_lun);
950 __put_user((short) sdp->device->queue_depth,
951 &sg_idp->d_queue_depth);
952 __put_user(0, &sg_idp->unused[0]);
953 __put_user(0, &sg_idp->unused[1]);
954 return 0;
955 }
956 case SG_SET_FORCE_PACK_ID:
957 result = get_user(val, ip);
958 if (result)
959 return result;
960 sfp->force_packid = val ? 1 : 0;
961 return 0;
962 case SG_GET_PACK_ID:
963 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
964 return -EFAULT;
965 read_lock_irqsave(&sfp->rq_list_lock, iflags);
966 list_for_each_entry(srp, &sfp->rq_list, entry) {
967 if ((1 == srp->done) && (!srp->sg_io_owned)) {
968 read_unlock_irqrestore(&sfp->rq_list_lock,
969 iflags);
970 __put_user(srp->header.pack_id, ip);
971 return 0;
972 }
973 }
974 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
975 __put_user(-1, ip);
976 return 0;
977 case SG_GET_NUM_WAITING:
978 read_lock_irqsave(&sfp->rq_list_lock, iflags);
979 val = 0;
980 list_for_each_entry(srp, &sfp->rq_list, entry) {
981 if ((1 == srp->done) && (!srp->sg_io_owned))
982 ++val;
983 }
984 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
985 return put_user(val, ip);
986 case SG_GET_SG_TABLESIZE:
987 return put_user(sdp->sg_tablesize, ip);
988 case SG_SET_RESERVED_SIZE:
989 result = get_user(val, ip);
990 if (result)
991 return result;
992 if (val < 0)
993 return -EINVAL;
994 val = min_t(int, val,
995 max_sectors_bytes(sdp->device->request_queue));
996 mutex_lock(&sfp->f_mutex);
997 if (val != sfp->reserve.bufflen) {
998 if (sfp->mmap_called ||
999 sfp->res_in_use) {
1000 mutex_unlock(&sfp->f_mutex);
1001 return -EBUSY;
1002 }
1003
1004 sg_remove_scat(sfp, &sfp->reserve);
1005 sg_build_reserve(sfp, val);
1006 }
1007 mutex_unlock(&sfp->f_mutex);
1008 return 0;
1009 case SG_GET_RESERVED_SIZE:
1010 val = min_t(int, sfp->reserve.bufflen,
1011 max_sectors_bytes(sdp->device->request_queue));
1012 return put_user(val, ip);
1013 case SG_SET_COMMAND_Q:
1014 result = get_user(val, ip);
1015 if (result)
1016 return result;
1017 sfp->cmd_q = val ? 1 : 0;
1018 return 0;
1019 case SG_GET_COMMAND_Q:
1020 return put_user((int) sfp->cmd_q, ip);
1021 case SG_SET_KEEP_ORPHAN:
1022 result = get_user(val, ip);
1023 if (result)
1024 return result;
1025 sfp->keep_orphan = val;
1026 return 0;
1027 case SG_GET_KEEP_ORPHAN:
1028 return put_user((int) sfp->keep_orphan, ip);
1029 case SG_NEXT_CMD_LEN:
1030 result = get_user(val, ip);
1031 if (result)
1032 return result;
1033 if (val > SG_MAX_CDB_SIZE)
1034 return -ENOMEM;
1035 sfp->next_cmd_len = (val > 0) ? val : 0;
1036 return 0;
1037 case SG_GET_VERSION_NUM:
1038 return put_user(sg_version_num, ip);
1039 case SG_GET_ACCESS_COUNT:
1040 /* faked - we don't have a real access count anymore */
1041 val = (sdp->device ? 1 : 0);
1042 return put_user(val, ip);
1043 case SG_GET_REQUEST_TABLE:
1044 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
1045 return -EFAULT;
1046 else {
1047 sg_req_info_t *rinfo;
1048
1049 rinfo = kzalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
1050 GFP_KERNEL);
1051 if (!rinfo)
1052 return -ENOMEM;
1053 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1054 sg_fill_request_table(sfp, rinfo);
1055 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1056 result = __copy_to_user(p, rinfo,
1057 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1058 result = result ? -EFAULT : 0;
1059 kfree(rinfo);
1060 return result;
1061 }
1062 case SG_EMULATED_HOST:
1063 if (atomic_read(&sdp->detaching))
1064 return -ENODEV;
1065 return put_user(sdp->device->host->hostt->emulated, ip);
1066 case SCSI_IOCTL_SEND_COMMAND:
1067 if (atomic_read(&sdp->detaching))
1068 return -ENODEV;
1069 if (read_only) {
1070 unsigned char opcode = WRITE_6;
1071 Scsi_Ioctl_Command __user *siocp = p;
1072
1073 if (copy_from_user(&opcode, siocp->data, 1))
1074 return -EFAULT;
1075 if (sg_allow_access(filp, &opcode))
1076 return -EPERM;
1077 }
1078 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1079 case SG_SET_DEBUG:
1080 result = get_user(val, ip);
1081 if (result)
1082 return result;
1083 sdp->sgdebug = (char) val;
1084 return 0;
1085 case BLKSECTGET:
1086 return put_user(max_sectors_bytes(sdp->device->request_queue),
1087 ip);
1088 case BLKTRACESETUP:
1089 return blk_trace_setup(sdp->device->request_queue,
1090 sdp->disk->disk_name,
1091 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1092 NULL, p);
1093 case BLKTRACESTART:
1094 return blk_trace_startstop(sdp->device->request_queue, 1);
1095 case BLKTRACESTOP:
1096 return blk_trace_startstop(sdp->device->request_queue, 0);
1097 case BLKTRACETEARDOWN:
1098 return blk_trace_remove(sdp->device->request_queue);
1099 case SCSI_IOCTL_GET_IDLUN:
1100 case SCSI_IOCTL_GET_BUS_NUMBER:
1101 case SCSI_IOCTL_PROBE_HOST:
1102 case SG_GET_TRANSFORM:
1103 case SG_SCSI_RESET:
1104 if (atomic_read(&sdp->detaching))
1105 return -ENODEV;
1106 break;
1107 default:
1108 if (read_only)
1109 return -EPERM; /* don't know so take safe approach */
1110 break;
1111 }
1112
1113 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1114 cmd_in, filp->f_flags & O_NDELAY);
1115 if (result)
1116 return result;
1117 return scsi_ioctl(sdp->device, cmd_in, p);
1118}
1119
1120#ifdef CONFIG_COMPAT
1121static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1122{
1123 Sg_device *sdp;
1124 Sg_fd *sfp;
1125 struct scsi_device *sdev;
1126
1127 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1128 return -ENXIO;
1129
1130 sdev = sdp->device;
1131 if (sdev->host->hostt->compat_ioctl) {
1132 int ret;
1133
1134 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1135
1136 return ret;
1137 }
1138
1139 return -ENOIOCTLCMD;
1140}
1141#endif
1142
1143static __poll_t
1144sg_poll(struct file *filp, poll_table * wait)
1145{
1146 __poll_t res = 0;
1147 Sg_device *sdp;
1148 Sg_fd *sfp;
1149 Sg_request *srp;
1150 int count = 0;
1151 unsigned long iflags;
1152
1153 sfp = filp->private_data;
1154 if (!sfp)
1155 return EPOLLERR;
1156 sdp = sfp->parentdp;
1157 if (!sdp)
1158 return EPOLLERR;
1159 poll_wait(filp, &sfp->read_wait, wait);
1160 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1161 list_for_each_entry(srp, &sfp->rq_list, entry) {
1162 /* if any read waiting, flag it */
1163 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1164 res = EPOLLIN | EPOLLRDNORM;
1165 ++count;
1166 }
1167 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1168
1169 if (atomic_read(&sdp->detaching))
1170 res |= EPOLLHUP;
1171 else if (!sfp->cmd_q) {
1172 if (0 == count)
1173 res |= EPOLLOUT | EPOLLWRNORM;
1174 } else if (count < SG_MAX_QUEUE)
1175 res |= EPOLLOUT | EPOLLWRNORM;
1176 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1177 "sg_poll: res=0x%x\n", (__force u32) res));
1178 return res;
1179}
1180
1181static int
1182sg_fasync(int fd, struct file *filp, int mode)
1183{
1184 Sg_device *sdp;
1185 Sg_fd *sfp;
1186
1187 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1188 return -ENXIO;
1189 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1190 "sg_fasync: mode=%d\n", mode));
1191
1192 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1193}
1194
1195static int
1196sg_vma_fault(struct vm_fault *vmf)
1197{
1198 struct vm_area_struct *vma = vmf->vma;
1199 Sg_fd *sfp;
1200 unsigned long offset, len, sa;
1201 Sg_scatter_hold *rsv_schp;
1202 int k, length;
1203
1204 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1205 return VM_FAULT_SIGBUS;
1206 rsv_schp = &sfp->reserve;
1207 offset = vmf->pgoff << PAGE_SHIFT;
1208 if (offset >= rsv_schp->bufflen)
1209 return VM_FAULT_SIGBUS;
1210 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1211 "sg_vma_fault: offset=%lu, scatg=%d\n",
1212 offset, rsv_schp->k_use_sg));
1213 sa = vma->vm_start;
1214 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1215 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1216 len = vma->vm_end - sa;
1217 len = (len < length) ? len : length;
1218 if (offset < len) {
1219 struct page *page = nth_page(rsv_schp->pages[k],
1220 offset >> PAGE_SHIFT);
1221 get_page(page); /* increment page count */
1222 vmf->page = page;
1223 return 0; /* success */
1224 }
1225 sa += len;
1226 offset -= len;
1227 }
1228
1229 return VM_FAULT_SIGBUS;
1230}
1231
1232static const struct vm_operations_struct sg_mmap_vm_ops = {
1233 .fault = sg_vma_fault,
1234};
1235
1236static int
1237sg_mmap(struct file *filp, struct vm_area_struct *vma)
1238{
1239 Sg_fd *sfp;
1240 unsigned long req_sz, len, sa;
1241 Sg_scatter_hold *rsv_schp;
1242 int k, length;
1243 int ret = 0;
1244
1245 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1246 return -ENXIO;
1247 req_sz = vma->vm_end - vma->vm_start;
1248 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1249 "sg_mmap starting, vm_start=%p, len=%d\n",
1250 (void *) vma->vm_start, (int) req_sz));
1251 if (vma->vm_pgoff)
1252 return -EINVAL; /* want no offset */
1253 rsv_schp = &sfp->reserve;
1254 mutex_lock(&sfp->f_mutex);
1255 if (req_sz > rsv_schp->bufflen) {
1256 ret = -ENOMEM; /* cannot map more than reserved buffer */
1257 goto out;
1258 }
1259
1260 sa = vma->vm_start;
1261 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1262 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1263 len = vma->vm_end - sa;
1264 len = (len < length) ? len : length;
1265 sa += len;
1266 }
1267
1268 sfp->mmap_called = 1;
1269 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1270 vma->vm_private_data = sfp;
1271 vma->vm_ops = &sg_mmap_vm_ops;
1272out:
1273 mutex_unlock(&sfp->f_mutex);
1274 return ret;
1275}
1276
1277static void
1278sg_rq_end_io_usercontext(struct work_struct *work)
1279{
1280 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1281 struct sg_fd *sfp = srp->parentfp;
1282
1283 sg_finish_rem_req(srp);
1284 sg_remove_request(sfp, srp);
1285 kref_put(&sfp->f_ref, sg_remove_sfp);
1286}
1287
1288/*
1289 * This function is a "bottom half" handler that is called by the mid
1290 * level when a command is completed (or has failed).
1291 */
1292static void
1293sg_rq_end_io(struct request *rq, blk_status_t status)
1294{
1295 struct sg_request *srp = rq->end_io_data;
1296 struct scsi_request *req = scsi_req(rq);
1297 Sg_device *sdp;
1298 Sg_fd *sfp;
1299 unsigned long iflags;
1300 unsigned int ms;
1301 char *sense;
1302 int result, resid, done = 1;
1303
1304 if (WARN_ON(srp->done != 0))
1305 return;
1306
1307 sfp = srp->parentfp;
1308 if (WARN_ON(sfp == NULL))
1309 return;
1310
1311 sdp = sfp->parentdp;
1312 if (unlikely(atomic_read(&sdp->detaching)))
1313 pr_info("%s: device detaching\n", __func__);
1314
1315 sense = req->sense;
1316 result = req->result;
1317 resid = req->resid_len;
1318
1319 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1320 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1321 srp->header.pack_id, result));
1322 srp->header.resid = resid;
1323 ms = jiffies_to_msecs(jiffies);
1324 srp->header.duration = (ms > srp->header.duration) ?
1325 (ms - srp->header.duration) : 0;
1326 if (0 != result) {
1327 struct scsi_sense_hdr sshdr;
1328
1329 srp->header.status = 0xff & result;
1330 srp->header.masked_status = status_byte(result);
1331 srp->header.msg_status = msg_byte(result);
1332 srp->header.host_status = host_byte(result);
1333 srp->header.driver_status = driver_byte(result);
1334 if ((sdp->sgdebug > 0) &&
1335 ((CHECK_CONDITION == srp->header.masked_status) ||
1336 (COMMAND_TERMINATED == srp->header.masked_status)))
1337 __scsi_print_sense(sdp->device, __func__, sense,
1338 SCSI_SENSE_BUFFERSIZE);
1339
1340 /* Following if statement is a patch supplied by Eric Youngdale */
1341 if (driver_byte(result) != 0
1342 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1343 && !scsi_sense_is_deferred(&sshdr)
1344 && sshdr.sense_key == UNIT_ATTENTION
1345 && sdp->device->removable) {
1346 /* Detected possible disc change. Set the bit - this */
1347 /* may be used if there are filesystems using this device */
1348 sdp->device->changed = 1;
1349 }
1350 }
1351
1352 if (req->sense_len)
1353 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1354
1355 /* Rely on write phase to clean out srp status values, so no "else" */
1356
1357 /*
1358 * Free the request as soon as it is complete so that its resources
1359 * can be reused without waiting for userspace to read() the
1360 * result. But keep the associated bio (if any) around until
1361 * blk_rq_unmap_user() can be called from user context.
1362 */
1363 srp->rq = NULL;
1364 scsi_req_free_cmd(scsi_req(rq));
1365 __blk_put_request(rq->q, rq);
1366
1367 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1368 if (unlikely(srp->orphan)) {
1369 if (sfp->keep_orphan)
1370 srp->sg_io_owned = 0;
1371 else
1372 done = 0;
1373 }
1374 srp->done = done;
1375 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1376
1377 if (likely(done)) {
1378 /* Now wake up any sg_read() that is waiting for this
1379 * packet.
1380 */
1381 wake_up_interruptible(&sfp->read_wait);
1382 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1383 kref_put(&sfp->f_ref, sg_remove_sfp);
1384 } else {
1385 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1386 schedule_work(&srp->ew.work);
1387 }
1388}
1389
1390static const struct file_operations sg_fops = {
1391 .owner = THIS_MODULE,
1392 .read = sg_read,
1393 .write = sg_write,
1394 .poll = sg_poll,
1395 .unlocked_ioctl = sg_ioctl,
1396#ifdef CONFIG_COMPAT
1397 .compat_ioctl = sg_compat_ioctl,
1398#endif
1399 .open = sg_open,
1400 .mmap = sg_mmap,
1401 .release = sg_release,
1402 .fasync = sg_fasync,
1403 .llseek = no_llseek,
1404};
1405
1406static struct class *sg_sysfs_class;
1407
1408static int sg_sysfs_valid = 0;
1409
1410static Sg_device *
1411sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1412{
1413 struct request_queue *q = scsidp->request_queue;
1414 Sg_device *sdp;
1415 unsigned long iflags;
1416 int error;
1417 u32 k;
1418
1419 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1420 if (!sdp) {
1421 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1422 "failure\n", __func__);
1423 return ERR_PTR(-ENOMEM);
1424 }
1425
1426 idr_preload(GFP_KERNEL);
1427 write_lock_irqsave(&sg_index_lock, iflags);
1428
1429 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1430 if (error < 0) {
1431 if (error == -ENOSPC) {
1432 sdev_printk(KERN_WARNING, scsidp,
1433 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1434 scsidp->type, SG_MAX_DEVS - 1);
1435 error = -ENODEV;
1436 } else {
1437 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1438 "allocation Sg_device failure: %d\n",
1439 __func__, error);
1440 }
1441 goto out_unlock;
1442 }
1443 k = error;
1444
1445 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1446 "sg_alloc: dev=%d \n", k));
1447 sprintf(disk->disk_name, "sg%d", k);
1448 disk->first_minor = k;
1449 sdp->disk = disk;
1450 sdp->device = scsidp;
1451 mutex_init(&sdp->open_rel_lock);
1452 INIT_LIST_HEAD(&sdp->sfds);
1453 init_waitqueue_head(&sdp->open_wait);
1454 atomic_set(&sdp->detaching, 0);
1455 rwlock_init(&sdp->sfd_lock);
1456 sdp->sg_tablesize = queue_max_segments(q);
1457 sdp->index = k;
1458 kref_init(&sdp->d_ref);
1459 error = 0;
1460
1461out_unlock:
1462 write_unlock_irqrestore(&sg_index_lock, iflags);
1463 idr_preload_end();
1464
1465 if (error) {
1466 kfree(sdp);
1467 return ERR_PTR(error);
1468 }
1469 return sdp;
1470}
1471
1472static int
1473sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1474{
1475 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1476 struct gendisk *disk;
1477 Sg_device *sdp = NULL;
1478 struct cdev * cdev = NULL;
1479 int error;
1480 unsigned long iflags;
1481
1482 disk = alloc_disk(1);
1483 if (!disk) {
1484 pr_warn("%s: alloc_disk failed\n", __func__);
1485 return -ENOMEM;
1486 }
1487 disk->major = SCSI_GENERIC_MAJOR;
1488
1489 error = -ENOMEM;
1490 cdev = cdev_alloc();
1491 if (!cdev) {
1492 pr_warn("%s: cdev_alloc failed\n", __func__);
1493 goto out;
1494 }
1495 cdev->owner = THIS_MODULE;
1496 cdev->ops = &sg_fops;
1497
1498 sdp = sg_alloc(disk, scsidp);
1499 if (IS_ERR(sdp)) {
1500 pr_warn("%s: sg_alloc failed\n", __func__);
1501 error = PTR_ERR(sdp);
1502 goto out;
1503 }
1504
1505 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1506 if (error)
1507 goto cdev_add_err;
1508
1509 sdp->cdev = cdev;
1510 if (sg_sysfs_valid) {
1511 struct device *sg_class_member;
1512
1513 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1514 MKDEV(SCSI_GENERIC_MAJOR,
1515 sdp->index),
1516 sdp, "%s", disk->disk_name);
1517 if (IS_ERR(sg_class_member)) {
1518 pr_err("%s: device_create failed\n", __func__);
1519 error = PTR_ERR(sg_class_member);
1520 goto cdev_add_err;
1521 }
1522 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1523 &sg_class_member->kobj, "generic");
1524 if (error)
1525 pr_err("%s: unable to make symlink 'generic' back "
1526 "to sg%d\n", __func__, sdp->index);
1527 } else
1528 pr_warn("%s: sg_sys Invalid\n", __func__);
1529
1530 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1531 "type %d\n", sdp->index, scsidp->type);
1532
1533 dev_set_drvdata(cl_dev, sdp);
1534
1535 return 0;
1536
1537cdev_add_err:
1538 write_lock_irqsave(&sg_index_lock, iflags);
1539 idr_remove(&sg_index_idr, sdp->index);
1540 write_unlock_irqrestore(&sg_index_lock, iflags);
1541 kfree(sdp);
1542
1543out:
1544 put_disk(disk);
1545 if (cdev)
1546 cdev_del(cdev);
1547 return error;
1548}
1549
1550static void
1551sg_device_destroy(struct kref *kref)
1552{
1553 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1554 unsigned long flags;
1555
1556 /* CAUTION! Note that the device can still be found via idr_find()
1557 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1558 * any other cleanup.
1559 */
1560
1561 write_lock_irqsave(&sg_index_lock, flags);
1562 idr_remove(&sg_index_idr, sdp->index);
1563 write_unlock_irqrestore(&sg_index_lock, flags);
1564
1565 SCSI_LOG_TIMEOUT(3,
1566 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1567
1568 put_disk(sdp->disk);
1569 kfree(sdp);
1570}
1571
1572static void
1573sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1574{
1575 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1576 Sg_device *sdp = dev_get_drvdata(cl_dev);
1577 unsigned long iflags;
1578 Sg_fd *sfp;
1579 int val;
1580
1581 if (!sdp)
1582 return;
1583 /* want sdp->detaching non-zero as soon as possible */
1584 val = atomic_inc_return(&sdp->detaching);
1585 if (val > 1)
1586 return; /* only want to do following once per device */
1587
1588 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1589 "%s\n", __func__));
1590
1591 read_lock_irqsave(&sdp->sfd_lock, iflags);
1592 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1593 wake_up_interruptible_all(&sfp->read_wait);
1594 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1595 }
1596 wake_up_interruptible_all(&sdp->open_wait);
1597 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1598
1599 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1600 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1601 cdev_del(sdp->cdev);
1602 sdp->cdev = NULL;
1603
1604 kref_put(&sdp->d_ref, sg_device_destroy);
1605}
1606
1607module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1608module_param_named(def_reserved_size, def_reserved_size, int,
1609 S_IRUGO | S_IWUSR);
1610module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1611
1612MODULE_AUTHOR("Douglas Gilbert");
1613MODULE_DESCRIPTION("SCSI generic (sg) driver");
1614MODULE_LICENSE("GPL");
1615MODULE_VERSION(SG_VERSION_STR);
1616MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1617
1618MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1619 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1620MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1621MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1622
1623static int __init
1624init_sg(void)
1625{
1626 int rc;
1627
1628 if (scatter_elem_sz < PAGE_SIZE) {
1629 scatter_elem_sz = PAGE_SIZE;
1630 scatter_elem_sz_prev = scatter_elem_sz;
1631 }
1632 if (def_reserved_size >= 0)
1633 sg_big_buff = def_reserved_size;
1634 else
1635 def_reserved_size = sg_big_buff;
1636
1637 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1638 SG_MAX_DEVS, "sg");
1639 if (rc)
1640 return rc;
1641 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1642 if ( IS_ERR(sg_sysfs_class) ) {
1643 rc = PTR_ERR(sg_sysfs_class);
1644 goto err_out;
1645 }
1646 sg_sysfs_valid = 1;
1647 rc = scsi_register_interface(&sg_interface);
1648 if (0 == rc) {
1649#ifdef CONFIG_SCSI_PROC_FS
1650 sg_proc_init();
1651#endif /* CONFIG_SCSI_PROC_FS */
1652 return 0;
1653 }
1654 class_destroy(sg_sysfs_class);
1655err_out:
1656 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1657 return rc;
1658}
1659
1660static void __exit
1661exit_sg(void)
1662{
1663#ifdef CONFIG_SCSI_PROC_FS
1664 sg_proc_cleanup();
1665#endif /* CONFIG_SCSI_PROC_FS */
1666 scsi_unregister_interface(&sg_interface);
1667 class_destroy(sg_sysfs_class);
1668 sg_sysfs_valid = 0;
1669 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1670 SG_MAX_DEVS);
1671 idr_destroy(&sg_index_idr);
1672}
1673
1674static int
1675sg_start_req(Sg_request *srp, unsigned char *cmd)
1676{
1677 int res;
1678 struct request *rq;
1679 struct scsi_request *req;
1680 Sg_fd *sfp = srp->parentfp;
1681 sg_io_hdr_t *hp = &srp->header;
1682 int dxfer_len = (int) hp->dxfer_len;
1683 int dxfer_dir = hp->dxfer_direction;
1684 unsigned int iov_count = hp->iovec_count;
1685 Sg_scatter_hold *req_schp = &srp->data;
1686 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1687 struct request_queue *q = sfp->parentdp->device->request_queue;
1688 struct rq_map_data *md, map_data;
1689 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1690 unsigned char *long_cmdp = NULL;
1691
1692 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1693 "sg_start_req: dxfer_len=%d\n",
1694 dxfer_len));
1695
1696 if (hp->cmd_len > BLK_MAX_CDB) {
1697 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1698 if (!long_cmdp)
1699 return -ENOMEM;
1700 }
1701
1702 /*
1703 * NOTE
1704 *
1705 * With scsi-mq enabled, there are a fixed number of preallocated
1706 * requests equal in number to shost->can_queue. If all of the
1707 * preallocated requests are already in use, then using GFP_ATOMIC with
1708 * blk_get_request() will return -EWOULDBLOCK, whereas using GFP_KERNEL
1709 * will cause blk_get_request() to sleep until an active command
1710 * completes, freeing up a request. Neither option is ideal, but
1711 * GFP_KERNEL is the better choice to prevent userspace from getting an
1712 * unexpected EWOULDBLOCK.
1713 *
1714 * With scsi-mq disabled, blk_get_request() with GFP_KERNEL usually
1715 * does not sleep except under memory pressure.
1716 */
1717 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1718 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, GFP_KERNEL);
1719 if (IS_ERR(rq)) {
1720 kfree(long_cmdp);
1721 return PTR_ERR(rq);
1722 }
1723 req = scsi_req(rq);
1724
1725 if (hp->cmd_len > BLK_MAX_CDB)
1726 req->cmd = long_cmdp;
1727 memcpy(req->cmd, cmd, hp->cmd_len);
1728 req->cmd_len = hp->cmd_len;
1729
1730 srp->rq = rq;
1731 rq->end_io_data = srp;
1732 req->retries = SG_DEFAULT_RETRIES;
1733
1734 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1735 return 0;
1736
1737 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1738 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1739 !sfp->parentdp->device->host->unchecked_isa_dma &&
1740 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1741 md = NULL;
1742 else
1743 md = &map_data;
1744
1745 if (md) {
1746 mutex_lock(&sfp->f_mutex);
1747 if (dxfer_len <= rsv_schp->bufflen &&
1748 !sfp->res_in_use) {
1749 sfp->res_in_use = 1;
1750 sg_link_reserve(sfp, srp, dxfer_len);
1751 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1752 res = -EBUSY; /* sfp->res_in_use == 1 */
1753 if (dxfer_len > rsv_schp->bufflen)
1754 res = -ENOMEM;
1755 mutex_unlock(&sfp->f_mutex);
1756 return res;
1757 } else {
1758 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1759 if (res) {
1760 mutex_unlock(&sfp->f_mutex);
1761 return res;
1762 }
1763 }
1764 mutex_unlock(&sfp->f_mutex);
1765
1766 md->pages = req_schp->pages;
1767 md->page_order = req_schp->page_order;
1768 md->nr_entries = req_schp->k_use_sg;
1769 md->offset = 0;
1770 md->null_mapped = hp->dxferp ? 0 : 1;
1771 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1772 md->from_user = 1;
1773 else
1774 md->from_user = 0;
1775 }
1776
1777 if (iov_count) {
1778 struct iovec *iov = NULL;
1779 struct iov_iter i;
1780
1781 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1782 if (res < 0)
1783 return res;
1784
1785 iov_iter_truncate(&i, hp->dxfer_len);
1786 if (!iov_iter_count(&i)) {
1787 kfree(iov);
1788 return -EINVAL;
1789 }
1790
1791 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1792 kfree(iov);
1793 } else
1794 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1795 hp->dxfer_len, GFP_ATOMIC);
1796
1797 if (!res) {
1798 srp->bio = rq->bio;
1799
1800 if (!md) {
1801 req_schp->dio_in_use = 1;
1802 hp->info |= SG_INFO_DIRECT_IO;
1803 }
1804 }
1805 return res;
1806}
1807
1808static int
1809sg_finish_rem_req(Sg_request *srp)
1810{
1811 int ret = 0;
1812
1813 Sg_fd *sfp = srp->parentfp;
1814 Sg_scatter_hold *req_schp = &srp->data;
1815
1816 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1817 "sg_finish_rem_req: res_used=%d\n",
1818 (int) srp->res_used));
1819 if (srp->bio)
1820 ret = blk_rq_unmap_user(srp->bio);
1821
1822 if (srp->rq) {
1823 scsi_req_free_cmd(scsi_req(srp->rq));
1824 blk_put_request(srp->rq);
1825 }
1826
1827 if (srp->res_used)
1828 sg_unlink_reserve(sfp, srp);
1829 else
1830 sg_remove_scat(sfp, req_schp);
1831
1832 return ret;
1833}
1834
1835static int
1836sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1837{
1838 int sg_bufflen = tablesize * sizeof(struct page *);
1839 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1840
1841 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1842 if (!schp->pages)
1843 return -ENOMEM;
1844 schp->sglist_len = sg_bufflen;
1845 return tablesize; /* number of scat_gath elements allocated */
1846}
1847
1848static int
1849sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1850{
1851 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1852 int sg_tablesize = sfp->parentdp->sg_tablesize;
1853 int blk_size = buff_size, order;
1854 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1855 struct sg_device *sdp = sfp->parentdp;
1856
1857 if (blk_size < 0)
1858 return -EFAULT;
1859 if (0 == blk_size)
1860 ++blk_size; /* don't know why */
1861 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1862 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1863 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1864 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1865 buff_size, blk_size));
1866
1867 /* N.B. ret_sz carried into this block ... */
1868 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1869 if (mx_sc_elems < 0)
1870 return mx_sc_elems; /* most likely -ENOMEM */
1871
1872 num = scatter_elem_sz;
1873 if (unlikely(num != scatter_elem_sz_prev)) {
1874 if (num < PAGE_SIZE) {
1875 scatter_elem_sz = PAGE_SIZE;
1876 scatter_elem_sz_prev = PAGE_SIZE;
1877 } else
1878 scatter_elem_sz_prev = num;
1879 }
1880
1881 if (sdp->device->host->unchecked_isa_dma)
1882 gfp_mask |= GFP_DMA;
1883
1884 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1885 gfp_mask |= __GFP_ZERO;
1886
1887 order = get_order(num);
1888retry:
1889 ret_sz = 1 << (PAGE_SHIFT + order);
1890
1891 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1892 k++, rem_sz -= ret_sz) {
1893
1894 num = (rem_sz > scatter_elem_sz_prev) ?
1895 scatter_elem_sz_prev : rem_sz;
1896
1897 schp->pages[k] = alloc_pages(gfp_mask | __GFP_ZERO, order);
1898 if (!schp->pages[k])
1899 goto out;
1900
1901 if (num == scatter_elem_sz_prev) {
1902 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1903 scatter_elem_sz = ret_sz;
1904 scatter_elem_sz_prev = ret_sz;
1905 }
1906 }
1907
1908 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1909 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1910 k, num, ret_sz));
1911 } /* end of for loop */
1912
1913 schp->page_order = order;
1914 schp->k_use_sg = k;
1915 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1916 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1917 k, rem_sz));
1918
1919 schp->bufflen = blk_size;
1920 if (rem_sz > 0) /* must have failed */
1921 return -ENOMEM;
1922 return 0;
1923out:
1924 for (i = 0; i < k; i++)
1925 __free_pages(schp->pages[i], order);
1926
1927 if (--order >= 0)
1928 goto retry;
1929
1930 return -ENOMEM;
1931}
1932
1933static void
1934sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1935{
1936 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1937 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1938 if (schp->pages && schp->sglist_len > 0) {
1939 if (!schp->dio_in_use) {
1940 int k;
1941
1942 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1943 SCSI_LOG_TIMEOUT(5,
1944 sg_printk(KERN_INFO, sfp->parentdp,
1945 "sg_remove_scat: k=%d, pg=0x%p\n",
1946 k, schp->pages[k]));
1947 __free_pages(schp->pages[k], schp->page_order);
1948 }
1949
1950 kfree(schp->pages);
1951 }
1952 }
1953 memset(schp, 0, sizeof (*schp));
1954}
1955
1956static int
1957sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1958{
1959 Sg_scatter_hold *schp = &srp->data;
1960 int k, num;
1961
1962 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1963 "sg_read_oxfer: num_read_xfer=%d\n",
1964 num_read_xfer));
1965 if ((!outp) || (num_read_xfer <= 0))
1966 return 0;
1967
1968 num = 1 << (PAGE_SHIFT + schp->page_order);
1969 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1970 if (num > num_read_xfer) {
1971 if (__copy_to_user(outp, page_address(schp->pages[k]),
1972 num_read_xfer))
1973 return -EFAULT;
1974 break;
1975 } else {
1976 if (__copy_to_user(outp, page_address(schp->pages[k]),
1977 num))
1978 return -EFAULT;
1979 num_read_xfer -= num;
1980 if (num_read_xfer <= 0)
1981 break;
1982 outp += num;
1983 }
1984 }
1985
1986 return 0;
1987}
1988
1989static void
1990sg_build_reserve(Sg_fd * sfp, int req_size)
1991{
1992 Sg_scatter_hold *schp = &sfp->reserve;
1993
1994 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1995 "sg_build_reserve: req_size=%d\n", req_size));
1996 do {
1997 if (req_size < PAGE_SIZE)
1998 req_size = PAGE_SIZE;
1999 if (0 == sg_build_indirect(schp, sfp, req_size))
2000 return;
2001 else
2002 sg_remove_scat(sfp, schp);
2003 req_size >>= 1; /* divide by 2 */
2004 } while (req_size > (PAGE_SIZE / 2));
2005}
2006
2007static void
2008sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2009{
2010 Sg_scatter_hold *req_schp = &srp->data;
2011 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2012 int k, num, rem;
2013
2014 srp->res_used = 1;
2015 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2016 "sg_link_reserve: size=%d\n", size));
2017 rem = size;
2018
2019 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2020 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2021 if (rem <= num) {
2022 req_schp->k_use_sg = k + 1;
2023 req_schp->sglist_len = rsv_schp->sglist_len;
2024 req_schp->pages = rsv_schp->pages;
2025
2026 req_schp->bufflen = size;
2027 req_schp->page_order = rsv_schp->page_order;
2028 break;
2029 } else
2030 rem -= num;
2031 }
2032
2033 if (k >= rsv_schp->k_use_sg)
2034 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2035 "sg_link_reserve: BAD size\n"));
2036}
2037
2038static void
2039sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2040{
2041 Sg_scatter_hold *req_schp = &srp->data;
2042
2043 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2044 "sg_unlink_reserve: req->k_use_sg=%d\n",
2045 (int) req_schp->k_use_sg));
2046 req_schp->k_use_sg = 0;
2047 req_schp->bufflen = 0;
2048 req_schp->pages = NULL;
2049 req_schp->page_order = 0;
2050 req_schp->sglist_len = 0;
2051 srp->res_used = 0;
2052 /* Called without mutex lock to avoid deadlock */
2053 sfp->res_in_use = 0;
2054}
2055
2056static Sg_request *
2057sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2058{
2059 Sg_request *resp;
2060 unsigned long iflags;
2061
2062 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2063 list_for_each_entry(resp, &sfp->rq_list, entry) {
2064 /* look for requests that are ready + not SG_IO owned */
2065 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2066 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2067 resp->done = 2; /* guard against other readers */
2068 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2069 return resp;
2070 }
2071 }
2072 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2073 return NULL;
2074}
2075
2076/* always adds to end of list */
2077static Sg_request *
2078sg_add_request(Sg_fd * sfp)
2079{
2080 int k;
2081 unsigned long iflags;
2082 Sg_request *rp = sfp->req_arr;
2083
2084 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2085 if (!list_empty(&sfp->rq_list)) {
2086 if (!sfp->cmd_q)
2087 goto out_unlock;
2088
2089 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2090 if (!rp->parentfp)
2091 break;
2092 }
2093 if (k >= SG_MAX_QUEUE)
2094 goto out_unlock;
2095 }
2096 memset(rp, 0, sizeof (Sg_request));
2097 rp->parentfp = sfp;
2098 rp->header.duration = jiffies_to_msecs(jiffies);
2099 list_add_tail(&rp->entry, &sfp->rq_list);
2100 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2101 return rp;
2102out_unlock:
2103 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2104 return NULL;
2105}
2106
2107/* Return of 1 for found; 0 for not found */
2108static int
2109sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2110{
2111 unsigned long iflags;
2112 int res = 0;
2113
2114 if (!sfp || !srp || list_empty(&sfp->rq_list))
2115 return res;
2116 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2117 if (!list_empty(&srp->entry)) {
2118 list_del(&srp->entry);
2119 srp->parentfp = NULL;
2120 res = 1;
2121 }
2122 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2123 return res;
2124}
2125
2126static Sg_fd *
2127sg_add_sfp(Sg_device * sdp)
2128{
2129 Sg_fd *sfp;
2130 unsigned long iflags;
2131 int bufflen;
2132
2133 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2134 if (!sfp)
2135 return ERR_PTR(-ENOMEM);
2136
2137 init_waitqueue_head(&sfp->read_wait);
2138 rwlock_init(&sfp->rq_list_lock);
2139 INIT_LIST_HEAD(&sfp->rq_list);
2140 kref_init(&sfp->f_ref);
2141 mutex_init(&sfp->f_mutex);
2142 sfp->timeout = SG_DEFAULT_TIMEOUT;
2143 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2144 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2145 sfp->cmd_q = SG_DEF_COMMAND_Q;
2146 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2147 sfp->parentdp = sdp;
2148 write_lock_irqsave(&sdp->sfd_lock, iflags);
2149 if (atomic_read(&sdp->detaching)) {
2150 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2151 return ERR_PTR(-ENODEV);
2152 }
2153 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2154 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2155 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2156 "sg_add_sfp: sfp=0x%p\n", sfp));
2157 if (unlikely(sg_big_buff != def_reserved_size))
2158 sg_big_buff = def_reserved_size;
2159
2160 bufflen = min_t(int, sg_big_buff,
2161 max_sectors_bytes(sdp->device->request_queue));
2162 sg_build_reserve(sfp, bufflen);
2163 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2164 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2165 sfp->reserve.bufflen,
2166 sfp->reserve.k_use_sg));
2167
2168 kref_get(&sdp->d_ref);
2169 __module_get(THIS_MODULE);
2170 return sfp;
2171}
2172
2173static void
2174sg_remove_sfp_usercontext(struct work_struct *work)
2175{
2176 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2177 struct sg_device *sdp = sfp->parentdp;
2178 Sg_request *srp;
2179 unsigned long iflags;
2180
2181 /* Cleanup any responses which were never read(). */
2182 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2183 while (!list_empty(&sfp->rq_list)) {
2184 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2185 sg_finish_rem_req(srp);
2186 list_del(&srp->entry);
2187 srp->parentfp = NULL;
2188 }
2189 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2190
2191 if (sfp->reserve.bufflen > 0) {
2192 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2193 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2194 (int) sfp->reserve.bufflen,
2195 (int) sfp->reserve.k_use_sg));
2196 sg_remove_scat(sfp, &sfp->reserve);
2197 }
2198
2199 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2200 "sg_remove_sfp: sfp=0x%p\n", sfp));
2201 kfree(sfp);
2202
2203 scsi_device_put(sdp->device);
2204 kref_put(&sdp->d_ref, sg_device_destroy);
2205 module_put(THIS_MODULE);
2206}
2207
2208static void
2209sg_remove_sfp(struct kref *kref)
2210{
2211 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2212 struct sg_device *sdp = sfp->parentdp;
2213 unsigned long iflags;
2214
2215 write_lock_irqsave(&sdp->sfd_lock, iflags);
2216 list_del(&sfp->sfd_siblings);
2217 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2218
2219 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2220 schedule_work(&sfp->ew.work);
2221}
2222
2223#ifdef CONFIG_SCSI_PROC_FS
2224static int
2225sg_idr_max_id(int id, void *p, void *data)
2226{
2227 int *k = data;
2228
2229 if (*k < id)
2230 *k = id;
2231
2232 return 0;
2233}
2234
2235static int
2236sg_last_dev(void)
2237{
2238 int k = -1;
2239 unsigned long iflags;
2240
2241 read_lock_irqsave(&sg_index_lock, iflags);
2242 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2243 read_unlock_irqrestore(&sg_index_lock, iflags);
2244 return k + 1; /* origin 1 */
2245}
2246#endif
2247
2248/* must be called with sg_index_lock held */
2249static Sg_device *sg_lookup_dev(int dev)
2250{
2251 return idr_find(&sg_index_idr, dev);
2252}
2253
2254static Sg_device *
2255sg_get_dev(int dev)
2256{
2257 struct sg_device *sdp;
2258 unsigned long flags;
2259
2260 read_lock_irqsave(&sg_index_lock, flags);
2261 sdp = sg_lookup_dev(dev);
2262 if (!sdp)
2263 sdp = ERR_PTR(-ENXIO);
2264 else if (atomic_read(&sdp->detaching)) {
2265 /* If sdp->detaching, then the refcount may already be 0, in
2266 * which case it would be a bug to do kref_get().
2267 */
2268 sdp = ERR_PTR(-ENODEV);
2269 } else
2270 kref_get(&sdp->d_ref);
2271 read_unlock_irqrestore(&sg_index_lock, flags);
2272
2273 return sdp;
2274}
2275
2276#ifdef CONFIG_SCSI_PROC_FS
2277
2278static struct proc_dir_entry *sg_proc_sgp = NULL;
2279
2280static char sg_proc_sg_dirname[] = "scsi/sg";
2281
2282static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2283
2284static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2285static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2286 size_t count, loff_t *off);
2287static const struct file_operations adio_fops = {
2288 .owner = THIS_MODULE,
2289 .open = sg_proc_single_open_adio,
2290 .read = seq_read,
2291 .llseek = seq_lseek,
2292 .write = sg_proc_write_adio,
2293 .release = single_release,
2294};
2295
2296static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2297static ssize_t sg_proc_write_dressz(struct file *filp,
2298 const char __user *buffer, size_t count, loff_t *off);
2299static const struct file_operations dressz_fops = {
2300 .owner = THIS_MODULE,
2301 .open = sg_proc_single_open_dressz,
2302 .read = seq_read,
2303 .llseek = seq_lseek,
2304 .write = sg_proc_write_dressz,
2305 .release = single_release,
2306};
2307
2308static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2309static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2310static const struct file_operations version_fops = {
2311 .owner = THIS_MODULE,
2312 .open = sg_proc_single_open_version,
2313 .read = seq_read,
2314 .llseek = seq_lseek,
2315 .release = single_release,
2316};
2317
2318static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2319static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2320static const struct file_operations devhdr_fops = {
2321 .owner = THIS_MODULE,
2322 .open = sg_proc_single_open_devhdr,
2323 .read = seq_read,
2324 .llseek = seq_lseek,
2325 .release = single_release,
2326};
2327
2328static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2329static int sg_proc_open_dev(struct inode *inode, struct file *file);
2330static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2331static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2332static void dev_seq_stop(struct seq_file *s, void *v);
2333static const struct file_operations dev_fops = {
2334 .owner = THIS_MODULE,
2335 .open = sg_proc_open_dev,
2336 .read = seq_read,
2337 .llseek = seq_lseek,
2338 .release = seq_release,
2339};
2340static const struct seq_operations dev_seq_ops = {
2341 .start = dev_seq_start,
2342 .next = dev_seq_next,
2343 .stop = dev_seq_stop,
2344 .show = sg_proc_seq_show_dev,
2345};
2346
2347static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2348static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2349static const struct file_operations devstrs_fops = {
2350 .owner = THIS_MODULE,
2351 .open = sg_proc_open_devstrs,
2352 .read = seq_read,
2353 .llseek = seq_lseek,
2354 .release = seq_release,
2355};
2356static const struct seq_operations devstrs_seq_ops = {
2357 .start = dev_seq_start,
2358 .next = dev_seq_next,
2359 .stop = dev_seq_stop,
2360 .show = sg_proc_seq_show_devstrs,
2361};
2362
2363static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2364static int sg_proc_open_debug(struct inode *inode, struct file *file);
2365static const struct file_operations debug_fops = {
2366 .owner = THIS_MODULE,
2367 .open = sg_proc_open_debug,
2368 .read = seq_read,
2369 .llseek = seq_lseek,
2370 .release = seq_release,
2371};
2372static const struct seq_operations debug_seq_ops = {
2373 .start = dev_seq_start,
2374 .next = dev_seq_next,
2375 .stop = dev_seq_stop,
2376 .show = sg_proc_seq_show_debug,
2377};
2378
2379
2380struct sg_proc_leaf {
2381 const char * name;
2382 const struct file_operations * fops;
2383};
2384
2385static const struct sg_proc_leaf sg_proc_leaf_arr[] = {
2386 {"allow_dio", &adio_fops},
2387 {"debug", &debug_fops},
2388 {"def_reserved_size", &dressz_fops},
2389 {"device_hdr", &devhdr_fops},
2390 {"devices", &dev_fops},
2391 {"device_strs", &devstrs_fops},
2392 {"version", &version_fops}
2393};
2394
2395static int
2396sg_proc_init(void)
2397{
2398 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2399 int k;
2400
2401 sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2402 if (!sg_proc_sgp)
2403 return 1;
2404 for (k = 0; k < num_leaves; ++k) {
2405 const struct sg_proc_leaf *leaf = &sg_proc_leaf_arr[k];
2406 umode_t mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2407 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2408 }
2409 return 0;
2410}
2411
2412static void
2413sg_proc_cleanup(void)
2414{
2415 int k;
2416 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2417
2418 if (!sg_proc_sgp)
2419 return;
2420 for (k = 0; k < num_leaves; ++k)
2421 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2422 remove_proc_entry(sg_proc_sg_dirname, NULL);
2423}
2424
2425
2426static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2427{
2428 seq_printf(s, "%d\n", *((int *)s->private));
2429 return 0;
2430}
2431
2432static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2433{
2434 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2435}
2436
2437static ssize_t
2438sg_proc_write_adio(struct file *filp, const char __user *buffer,
2439 size_t count, loff_t *off)
2440{
2441 int err;
2442 unsigned long num;
2443
2444 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2445 return -EACCES;
2446 err = kstrtoul_from_user(buffer, count, 0, &num);
2447 if (err)
2448 return err;
2449 sg_allow_dio = num ? 1 : 0;
2450 return count;
2451}
2452
2453static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2454{
2455 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2456}
2457
2458static ssize_t
2459sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2460 size_t count, loff_t *off)
2461{
2462 int err;
2463 unsigned long k = ULONG_MAX;
2464
2465 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2466 return -EACCES;
2467
2468 err = kstrtoul_from_user(buffer, count, 0, &k);
2469 if (err)
2470 return err;
2471 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2472 sg_big_buff = k;
2473 return count;
2474 }
2475 return -ERANGE;
2476}
2477
2478static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2479{
2480 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2481 sg_version_date);
2482 return 0;
2483}
2484
2485static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2486{
2487 return single_open(file, sg_proc_seq_show_version, NULL);
2488}
2489
2490static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2491{
2492 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2493 return 0;
2494}
2495
2496static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2497{
2498 return single_open(file, sg_proc_seq_show_devhdr, NULL);
2499}
2500
2501struct sg_proc_deviter {
2502 loff_t index;
2503 size_t max;
2504};
2505
2506static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2507{
2508 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2509
2510 s->private = it;
2511 if (! it)
2512 return NULL;
2513
2514 it->index = *pos;
2515 it->max = sg_last_dev();
2516 if (it->index >= it->max)
2517 return NULL;
2518 return it;
2519}
2520
2521static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2522{
2523 struct sg_proc_deviter * it = s->private;
2524
2525 *pos = ++it->index;
2526 return (it->index < it->max) ? it : NULL;
2527}
2528
2529static void dev_seq_stop(struct seq_file *s, void *v)
2530{
2531 kfree(s->private);
2532}
2533
2534static int sg_proc_open_dev(struct inode *inode, struct file *file)
2535{
2536 return seq_open(file, &dev_seq_ops);
2537}
2538
2539static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2540{
2541 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2542 Sg_device *sdp;
2543 struct scsi_device *scsidp;
2544 unsigned long iflags;
2545
2546 read_lock_irqsave(&sg_index_lock, iflags);
2547 sdp = it ? sg_lookup_dev(it->index) : NULL;
2548 if ((NULL == sdp) || (NULL == sdp->device) ||
2549 (atomic_read(&sdp->detaching)))
2550 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2551 else {
2552 scsidp = sdp->device;
2553 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2554 scsidp->host->host_no, scsidp->channel,
2555 scsidp->id, scsidp->lun, (int) scsidp->type,
2556 1,
2557 (int) scsidp->queue_depth,
2558 (int) atomic_read(&scsidp->device_busy),
2559 (int) scsi_device_online(scsidp));
2560 }
2561 read_unlock_irqrestore(&sg_index_lock, iflags);
2562 return 0;
2563}
2564
2565static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2566{
2567 return seq_open(file, &devstrs_seq_ops);
2568}
2569
2570static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2571{
2572 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2573 Sg_device *sdp;
2574 struct scsi_device *scsidp;
2575 unsigned long iflags;
2576
2577 read_lock_irqsave(&sg_index_lock, iflags);
2578 sdp = it ? sg_lookup_dev(it->index) : NULL;
2579 scsidp = sdp ? sdp->device : NULL;
2580 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2581 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2582 scsidp->vendor, scsidp->model, scsidp->rev);
2583 else
2584 seq_puts(s, "<no active device>\n");
2585 read_unlock_irqrestore(&sg_index_lock, iflags);
2586 return 0;
2587}
2588
2589/* must be called while holding sg_index_lock */
2590static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2591{
2592 int k, new_interface, blen, usg;
2593 Sg_request *srp;
2594 Sg_fd *fp;
2595 const sg_io_hdr_t *hp;
2596 const char * cp;
2597 unsigned int ms;
2598
2599 k = 0;
2600 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2601 k++;
2602 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2603 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2604 "(res)sgat=%d low_dma=%d\n", k,
2605 jiffies_to_msecs(fp->timeout),
2606 fp->reserve.bufflen,
2607 (int) fp->reserve.k_use_sg,
2608 (int) sdp->device->host->unchecked_isa_dma);
2609 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2610 (int) fp->cmd_q, (int) fp->force_packid,
2611 (int) fp->keep_orphan);
2612 list_for_each_entry(srp, &fp->rq_list, entry) {
2613 hp = &srp->header;
2614 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2615 if (srp->res_used) {
2616 if (new_interface &&
2617 (SG_FLAG_MMAP_IO & hp->flags))
2618 cp = " mmap>> ";
2619 else
2620 cp = " rb>> ";
2621 } else {
2622 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2623 cp = " dio>> ";
2624 else
2625 cp = " ";
2626 }
2627 seq_puts(s, cp);
2628 blen = srp->data.bufflen;
2629 usg = srp->data.k_use_sg;
2630 seq_puts(s, srp->done ?
2631 ((1 == srp->done) ? "rcv:" : "fin:")
2632 : "act:");
2633 seq_printf(s, " id=%d blen=%d",
2634 srp->header.pack_id, blen);
2635 if (srp->done)
2636 seq_printf(s, " dur=%d", hp->duration);
2637 else {
2638 ms = jiffies_to_msecs(jiffies);
2639 seq_printf(s, " t_o/elap=%d/%d",
2640 (new_interface ? hp->timeout :
2641 jiffies_to_msecs(fp->timeout)),
2642 (ms > hp->duration ? ms - hp->duration : 0));
2643 }
2644 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2645 (int) srp->data.cmd_opcode);
2646 }
2647 if (list_empty(&fp->rq_list))
2648 seq_puts(s, " No requests active\n");
2649 read_unlock(&fp->rq_list_lock);
2650 }
2651}
2652
2653static int sg_proc_open_debug(struct inode *inode, struct file *file)
2654{
2655 return seq_open(file, &debug_seq_ops);
2656}
2657
2658static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2659{
2660 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2661 Sg_device *sdp;
2662 unsigned long iflags;
2663
2664 if (it && (0 == it->index))
2665 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2666 (int)it->max, sg_big_buff);
2667
2668 read_lock_irqsave(&sg_index_lock, iflags);
2669 sdp = it ? sg_lookup_dev(it->index) : NULL;
2670 if (NULL == sdp)
2671 goto skip;
2672 read_lock(&sdp->sfd_lock);
2673 if (!list_empty(&sdp->sfds)) {
2674 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2675 if (atomic_read(&sdp->detaching))
2676 seq_puts(s, "detaching pending close ");
2677 else if (sdp->device) {
2678 struct scsi_device *scsidp = sdp->device;
2679
2680 seq_printf(s, "%d:%d:%d:%llu em=%d",
2681 scsidp->host->host_no,
2682 scsidp->channel, scsidp->id,
2683 scsidp->lun,
2684 scsidp->host->hostt->emulated);
2685 }
2686 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2687 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2688 sg_proc_debug_helper(s, sdp);
2689 }
2690 read_unlock(&sdp->sfd_lock);
2691skip:
2692 read_unlock_irqrestore(&sg_index_lock, iflags);
2693 return 0;
2694}
2695
2696#endif /* CONFIG_SCSI_PROC_FS */
2697
2698module_init(init_sg);
2699module_exit(exit_sg);