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