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interconnect: qcom: Fix Kconfig indentation
[linux/fpc-iii.git] / drivers / scsi / sg.c
blob160748ad9c0f06d3a8dcfa1802c27bddac4ee8c7
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 ssize_t
409 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
410 {
411 Sg_device *sdp;
412 Sg_fd *sfp;
413 Sg_request *srp;
414 int req_pack_id = -1;
415 sg_io_hdr_t *hp;
416 struct sg_header *old_hdr = NULL;
417 int retval = 0;
418
419 /*
420 * This could cause a response to be stranded. Close the associated
421 * file descriptor to free up any resources being held.
422 */
423 retval = sg_check_file_access(filp, __func__);
424 if (retval)
425 return retval;
426
427 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
428 return -ENXIO;
429 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
430 "sg_read: count=%d\n", (int) count));
431
432 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
433 old_hdr = memdup_user(buf, SZ_SG_HEADER);
434 if (IS_ERR(old_hdr))
435 return PTR_ERR(old_hdr);
436 if (old_hdr->reply_len < 0) {
437 if (count >= SZ_SG_IO_HDR) {
438 /*
439 * This is stupid.
440 *
441 * We're copying the whole sg_io_hdr_t from user
442 * space just to get the 'pack_id' field. But the
443 * field is at different offsets for the compat
444 * case, so we'll use "get_sg_io_hdr()" to copy
445 * the whole thing and convert it.
446 *
447 * We could do something like just calculating the
448 * offset based of 'in_compat_syscall()', but the
449 * 'compat_sg_io_hdr' definition is in the wrong
450 * place for that.
451 */
452 sg_io_hdr_t *new_hdr;
453 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
454 if (!new_hdr) {
455 retval = -ENOMEM;
456 goto free_old_hdr;
457 }
458 retval = get_sg_io_hdr(new_hdr, buf);
459 req_pack_id = new_hdr->pack_id;
460 kfree(new_hdr);
461 if (retval) {
462 retval = -EFAULT;
463 goto free_old_hdr;
464 }
465 }
466 } else
467 req_pack_id = old_hdr->pack_id;
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 retval = -ENODEV;
473 goto free_old_hdr;
474 }
475 if (filp->f_flags & O_NONBLOCK) {
476 retval = -EAGAIN;
477 goto free_old_hdr;
478 }
479 retval = wait_event_interruptible(sfp->read_wait,
480 (atomic_read(&sdp->detaching) ||
481 (srp = sg_get_rq_mark(sfp, req_pack_id))));
482 if (atomic_read(&sdp->detaching)) {
483 retval = -ENODEV;
484 goto free_old_hdr;
485 }
486 if (retval) {
487 /* -ERESTARTSYS as signal hit process */
488 goto free_old_hdr;
489 }
490 }
491 if (srp->header.interface_id != '\0') {
492 retval = sg_new_read(sfp, buf, count, srp);
493 goto free_old_hdr;
494 }
495
496 hp = &srp->header;
497 if (old_hdr == NULL) {
498 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
499 if (! old_hdr) {
500 retval = -ENOMEM;
501 goto free_old_hdr;
502 }
503 }
504 memset(old_hdr, 0, SZ_SG_HEADER);
505 old_hdr->reply_len = (int) hp->timeout;
506 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
507 old_hdr->pack_id = hp->pack_id;
508 old_hdr->twelve_byte =
509 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
510 old_hdr->target_status = hp->masked_status;
511 old_hdr->host_status = hp->host_status;
512 old_hdr->driver_status = hp->driver_status;
513 if ((CHECK_CONDITION & hp->masked_status) ||
514 (DRIVER_SENSE & hp->driver_status))
515 memcpy(old_hdr->sense_buffer, srp->sense_b,
516 sizeof (old_hdr->sense_buffer));
517 switch (hp->host_status) {
518 /* This setup of 'result' is for backward compatibility and is best
519 ignored by the user who should use target, host + driver status */
520 case DID_OK:
521 case DID_PASSTHROUGH:
522 case DID_SOFT_ERROR:
523 old_hdr->result = 0;
524 break;
525 case DID_NO_CONNECT:
526 case DID_BUS_BUSY:
527 case DID_TIME_OUT:
528 old_hdr->result = EBUSY;
529 break;
530 case DID_BAD_TARGET:
531 case DID_ABORT:
532 case DID_PARITY:
533 case DID_RESET:
534 case DID_BAD_INTR:
535 old_hdr->result = EIO;
536 break;
537 case DID_ERROR:
538 old_hdr->result = (srp->sense_b[0] == 0 &&
539 hp->masked_status == GOOD) ? 0 : EIO;
540 break;
541 default:
542 old_hdr->result = EIO;
543 break;
544 }
545
546 /* Now copy the result back to the user buffer. */
547 if (count >= SZ_SG_HEADER) {
548 if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
549 retval = -EFAULT;
550 goto free_old_hdr;
551 }
552 buf += SZ_SG_HEADER;
553 if (count > old_hdr->reply_len)
554 count = old_hdr->reply_len;
555 if (count > SZ_SG_HEADER) {
556 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
557 retval = -EFAULT;
558 goto free_old_hdr;
559 }
560 }
561 } else
562 count = (old_hdr->result == 0) ? 0 : -EIO;
563 sg_finish_rem_req(srp);
564 sg_remove_request(sfp, srp);
565 retval = count;
566 free_old_hdr:
567 kfree(old_hdr);
568 return retval;
569 }
570
571 static ssize_t
572 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
573 {
574 sg_io_hdr_t *hp = &srp->header;
575 int err = 0, err2;
576 int len;
577
578 if (count < SZ_SG_IO_HDR) {
579 err = -EINVAL;
580 goto err_out;
581 }
582 hp->sb_len_wr = 0;
583 if ((hp->mx_sb_len > 0) && hp->sbp) {
584 if ((CHECK_CONDITION & hp->masked_status) ||
585 (DRIVER_SENSE & hp->driver_status)) {
586 int sb_len = SCSI_SENSE_BUFFERSIZE;
587 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
588 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
589 len = (len > sb_len) ? sb_len : len;
590 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
591 err = -EFAULT;
592 goto err_out;
593 }
594 hp->sb_len_wr = len;
595 }
596 }
597 if (hp->masked_status || hp->host_status || hp->driver_status)
598 hp->info |= SG_INFO_CHECK;
599 err = put_sg_io_hdr(hp, buf);
600 err_out:
601 err2 = sg_finish_rem_req(srp);
602 sg_remove_request(sfp, srp);
603 return err ? : err2 ? : count;
604 }
605
606 static ssize_t
607 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
608 {
609 int mxsize, cmd_size, k;
610 int input_size, blocking;
611 unsigned char opcode;
612 Sg_device *sdp;
613 Sg_fd *sfp;
614 Sg_request *srp;
615 struct sg_header old_hdr;
616 sg_io_hdr_t *hp;
617 unsigned char cmnd[SG_MAX_CDB_SIZE];
618 int retval;
619
620 retval = sg_check_file_access(filp, __func__);
621 if (retval)
622 return retval;
623
624 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
625 return -ENXIO;
626 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
627 "sg_write: count=%d\n", (int) count));
628 if (atomic_read(&sdp->detaching))
629 return -ENODEV;
630 if (!((filp->f_flags & O_NONBLOCK) ||
631 scsi_block_when_processing_errors(sdp->device)))
632 return -ENXIO;
633
634 if (count < SZ_SG_HEADER)
635 return -EIO;
636 if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
637 return -EFAULT;
638 blocking = !(filp->f_flags & O_NONBLOCK);
639 if (old_hdr.reply_len < 0)
640 return sg_new_write(sfp, filp, buf, count,
641 blocking, 0, 0, NULL);
642 if (count < (SZ_SG_HEADER + 6))
643 return -EIO; /* The minimum scsi command length is 6 bytes. */
644
645 buf += SZ_SG_HEADER;
646 if (get_user(opcode, buf))
647 return -EFAULT;
648
649 if (!(srp = sg_add_request(sfp))) {
650 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
651 "sg_write: queue full\n"));
652 return -EDOM;
653 }
654 mutex_lock(&sfp->f_mutex);
655 if (sfp->next_cmd_len > 0) {
656 cmd_size = sfp->next_cmd_len;
657 sfp->next_cmd_len = 0; /* reset so only this write() effected */
658 } else {
659 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
660 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
661 cmd_size = 12;
662 }
663 mutex_unlock(&sfp->f_mutex);
664 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
665 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
666 /* Determine buffer size. */
667 input_size = count - cmd_size;
668 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
669 mxsize -= SZ_SG_HEADER;
670 input_size -= SZ_SG_HEADER;
671 if (input_size < 0) {
672 sg_remove_request(sfp, srp);
673 return -EIO; /* User did not pass enough bytes for this command. */
674 }
675 hp = &srp->header;
676 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
677 hp->cmd_len = (unsigned char) cmd_size;
678 hp->iovec_count = 0;
679 hp->mx_sb_len = 0;
680 if (input_size > 0)
681 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
682 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
683 else
684 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
685 hp->dxfer_len = mxsize;
686 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
687 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
688 hp->dxferp = (char __user *)buf + cmd_size;
689 else
690 hp->dxferp = NULL;
691 hp->sbp = NULL;
692 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
693 hp->flags = input_size; /* structure abuse ... */
694 hp->pack_id = old_hdr.pack_id;
695 hp->usr_ptr = NULL;
696 if (copy_from_user(cmnd, buf, cmd_size))
697 return -EFAULT;
698 /*
699 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
700 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
701 * is a non-zero input_size, so emit a warning.
702 */
703 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
704 printk_ratelimited(KERN_WARNING
705 "sg_write: data in/out %d/%d bytes "
706 "for SCSI command 0x%x-- guessing "
707 "data in;\n program %s not setting "
708 "count and/or reply_len properly\n",
709 old_hdr.reply_len - (int)SZ_SG_HEADER,
710 input_size, (unsigned int) cmnd[0],
711 current->comm);
712 }
713 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
714 return (k < 0) ? k : count;
715 }
716
717 static ssize_t
718 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
719 size_t count, int blocking, int read_only, int sg_io_owned,
720 Sg_request **o_srp)
721 {
722 int k;
723 Sg_request *srp;
724 sg_io_hdr_t *hp;
725 unsigned char cmnd[SG_MAX_CDB_SIZE];
726 int timeout;
727 unsigned long ul_timeout;
728
729 if (count < SZ_SG_IO_HDR)
730 return -EINVAL;
731
732 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
733 if (!(srp = sg_add_request(sfp))) {
734 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
735 "sg_new_write: queue full\n"));
736 return -EDOM;
737 }
738 srp->sg_io_owned = sg_io_owned;
739 hp = &srp->header;
740 if (get_sg_io_hdr(hp, buf)) {
741 sg_remove_request(sfp, srp);
742 return -EFAULT;
743 }
744 if (hp->interface_id != 'S') {
745 sg_remove_request(sfp, srp);
746 return -ENOSYS;
747 }
748 if (hp->flags & SG_FLAG_MMAP_IO) {
749 if (hp->dxfer_len > sfp->reserve.bufflen) {
750 sg_remove_request(sfp, srp);
751 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
752 }
753 if (hp->flags & SG_FLAG_DIRECT_IO) {
754 sg_remove_request(sfp, srp);
755 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
756 }
757 if (sfp->res_in_use) {
758 sg_remove_request(sfp, srp);
759 return -EBUSY; /* reserve buffer already being used */
760 }
761 }
762 ul_timeout = msecs_to_jiffies(srp->header.timeout);
763 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
764 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
765 sg_remove_request(sfp, srp);
766 return -EMSGSIZE;
767 }
768 if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
769 sg_remove_request(sfp, srp);
770 return -EFAULT;
771 }
772 if (read_only && sg_allow_access(file, cmnd)) {
773 sg_remove_request(sfp, srp);
774 return -EPERM;
775 }
776 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
777 if (k < 0)
778 return k;
779 if (o_srp)
780 *o_srp = srp;
781 return count;
782 }
783
784 static int
785 sg_common_write(Sg_fd * sfp, Sg_request * srp,
786 unsigned char *cmnd, int timeout, int blocking)
787 {
788 int k, at_head;
789 Sg_device *sdp = sfp->parentdp;
790 sg_io_hdr_t *hp = &srp->header;
791
792 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
793 hp->status = 0;
794 hp->masked_status = 0;
795 hp->msg_status = 0;
796 hp->info = 0;
797 hp->host_status = 0;
798 hp->driver_status = 0;
799 hp->resid = 0;
800 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
801 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
802 (int) cmnd[0], (int) hp->cmd_len));
803
804 if (hp->dxfer_len >= SZ_256M)
805 return -EINVAL;
806
807 k = sg_start_req(srp, cmnd);
808 if (k) {
809 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
810 "sg_common_write: start_req err=%d\n", k));
811 sg_finish_rem_req(srp);
812 sg_remove_request(sfp, srp);
813 return k; /* probably out of space --> ENOMEM */
814 }
815 if (atomic_read(&sdp->detaching)) {
816 if (srp->bio) {
817 scsi_req_free_cmd(scsi_req(srp->rq));
818 blk_put_request(srp->rq);
819 srp->rq = NULL;
820 }
821
822 sg_finish_rem_req(srp);
823 sg_remove_request(sfp, srp);
824 return -ENODEV;
825 }
826
827 hp->duration = jiffies_to_msecs(jiffies);
828 if (hp->interface_id != '\0' && /* v3 (or later) interface */
829 (SG_FLAG_Q_AT_TAIL & hp->flags))
830 at_head = 0;
831 else
832 at_head = 1;
833
834 srp->rq->timeout = timeout;
835 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
836 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
837 srp->rq, at_head, sg_rq_end_io);
838 return 0;
839 }
840
841 static int srp_done(Sg_fd *sfp, Sg_request *srp)
842 {
843 unsigned long flags;
844 int ret;
845
846 read_lock_irqsave(&sfp->rq_list_lock, flags);
847 ret = srp->done;
848 read_unlock_irqrestore(&sfp->rq_list_lock, flags);
849 return ret;
850 }
851
852 static int max_sectors_bytes(struct request_queue *q)
853 {
854 unsigned int max_sectors = queue_max_sectors(q);
855
856 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
857
858 return max_sectors << 9;
859 }
860
861 static void
862 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)
863 {
864 Sg_request *srp;
865 int val;
866 unsigned int ms;
867
868 val = 0;
869 list_for_each_entry(srp, &sfp->rq_list, entry) {
870 if (val >= SG_MAX_QUEUE)
871 break;
872 rinfo[val].req_state = srp->done + 1;
873 rinfo[val].problem =
874 srp->header.masked_status &
875 srp->header.host_status &
876 srp->header.driver_status;
877 if (srp->done)
878 rinfo[val].duration =
879 srp->header.duration;
880 else {
881 ms = jiffies_to_msecs(jiffies);
882 rinfo[val].duration =
883 (ms > srp->header.duration) ?
884 (ms - srp->header.duration) : 0;
885 }
886 rinfo[val].orphan = srp->orphan;
887 rinfo[val].sg_io_owned = srp->sg_io_owned;
888 rinfo[val].pack_id = srp->header.pack_id;
889 rinfo[val].usr_ptr = srp->header.usr_ptr;
890 val++;
891 }
892 }
893
894 #ifdef CONFIG_COMPAT
895 struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */
896 char req_state;
897 char orphan;
898 char sg_io_owned;
899 char problem;
900 int pack_id;
901 compat_uptr_t usr_ptr;
902 unsigned int duration;
903 int unused;
904 };
905
906 static int put_compat_request_table(struct compat_sg_req_info __user *o,
907 struct sg_req_info *rinfo)
908 {
909 int i;
910 for (i = 0; i < SG_MAX_QUEUE; i++) {
911 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) ||
912 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) ||
913 put_user(rinfo[i].duration, &o[i].duration) ||
914 put_user(rinfo[i].unused, &o[i].unused))
915 return -EFAULT;
916 }
917 return 0;
918 }
919 #endif
920
921 static long
922 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
923 {
924 void __user *p = (void __user *)arg;
925 int __user *ip = p;
926 int result, val, read_only;
927 Sg_device *sdp;
928 Sg_fd *sfp;
929 Sg_request *srp;
930 unsigned long iflags;
931
932 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
933 return -ENXIO;
934
935 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
936 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
937 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
938
939 switch (cmd_in) {
940 case SG_IO:
941 if (atomic_read(&sdp->detaching))
942 return -ENODEV;
943 if (!scsi_block_when_processing_errors(sdp->device))
944 return -ENXIO;
945 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
946 1, read_only, 1, &srp);
947 if (result < 0)
948 return result;
949 result = wait_event_interruptible(sfp->read_wait,
950 (srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
951 if (atomic_read(&sdp->detaching))
952 return -ENODEV;
953 write_lock_irq(&sfp->rq_list_lock);
954 if (srp->done) {
955 srp->done = 2;
956 write_unlock_irq(&sfp->rq_list_lock);
957 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
958 return (result < 0) ? result : 0;
959 }
960 srp->orphan = 1;
961 write_unlock_irq(&sfp->rq_list_lock);
962 return result; /* -ERESTARTSYS because signal hit process */
963 case SG_SET_TIMEOUT:
964 result = get_user(val, ip);
965 if (result)
966 return result;
967 if (val < 0)
968 return -EIO;
969 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
970 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
971 INT_MAX);
972 sfp->timeout_user = val;
973 sfp->timeout = mult_frac(val, HZ, USER_HZ);
974
975 return 0;
976 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
977 /* strange ..., for backward compatibility */
978 return sfp->timeout_user;
979 case SG_SET_FORCE_LOW_DMA:
980 /*
981 * N.B. This ioctl never worked properly, but failed to
982 * return an error value. So returning '0' to keep compability
983 * with legacy applications.
984 */
985 return 0;
986 case SG_GET_LOW_DMA:
987 return put_user((int) sdp->device->host->unchecked_isa_dma, ip);
988 case SG_GET_SCSI_ID:
989 {
990 sg_scsi_id_t v;
991
992 if (atomic_read(&sdp->detaching))
993 return -ENODEV;
994 memset(&v, 0, sizeof(v));
995 v.host_no = sdp->device->host->host_no;
996 v.channel = sdp->device->channel;
997 v.scsi_id = sdp->device->id;
998 v.lun = sdp->device->lun;
999 v.scsi_type = sdp->device->type;
1000 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun;
1001 v.d_queue_depth = sdp->device->queue_depth;
1002 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t)))
1003 return -EFAULT;
1004 return 0;
1005 }
1006 case SG_SET_FORCE_PACK_ID:
1007 result = get_user(val, ip);
1008 if (result)
1009 return result;
1010 sfp->force_packid = val ? 1 : 0;
1011 return 0;
1012 case SG_GET_PACK_ID:
1013 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1014 list_for_each_entry(srp, &sfp->rq_list, entry) {
1015 if ((1 == srp->done) && (!srp->sg_io_owned)) {
1016 read_unlock_irqrestore(&sfp->rq_list_lock,
1017 iflags);
1018 return put_user(srp->header.pack_id, ip);
1019 }
1020 }
1021 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1022 return put_user(-1, ip);
1023 case SG_GET_NUM_WAITING:
1024 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1025 val = 0;
1026 list_for_each_entry(srp, &sfp->rq_list, entry) {
1027 if ((1 == srp->done) && (!srp->sg_io_owned))
1028 ++val;
1029 }
1030 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1031 return put_user(val, ip);
1032 case SG_GET_SG_TABLESIZE:
1033 return put_user(sdp->sg_tablesize, ip);
1034 case SG_SET_RESERVED_SIZE:
1035 result = get_user(val, ip);
1036 if (result)
1037 return result;
1038 if (val < 0)
1039 return -EINVAL;
1040 val = min_t(int, val,
1041 max_sectors_bytes(sdp->device->request_queue));
1042 mutex_lock(&sfp->f_mutex);
1043 if (val != sfp->reserve.bufflen) {
1044 if (sfp->mmap_called ||
1045 sfp->res_in_use) {
1046 mutex_unlock(&sfp->f_mutex);
1047 return -EBUSY;
1048 }
1049
1050 sg_remove_scat(sfp, &sfp->reserve);
1051 sg_build_reserve(sfp, val);
1052 }
1053 mutex_unlock(&sfp->f_mutex);
1054 return 0;
1055 case SG_GET_RESERVED_SIZE:
1056 val = min_t(int, sfp->reserve.bufflen,
1057 max_sectors_bytes(sdp->device->request_queue));
1058 return put_user(val, ip);
1059 case SG_SET_COMMAND_Q:
1060 result = get_user(val, ip);
1061 if (result)
1062 return result;
1063 sfp->cmd_q = val ? 1 : 0;
1064 return 0;
1065 case SG_GET_COMMAND_Q:
1066 return put_user((int) sfp->cmd_q, ip);
1067 case SG_SET_KEEP_ORPHAN:
1068 result = get_user(val, ip);
1069 if (result)
1070 return result;
1071 sfp->keep_orphan = val;
1072 return 0;
1073 case SG_GET_KEEP_ORPHAN:
1074 return put_user((int) sfp->keep_orphan, ip);
1075 case SG_NEXT_CMD_LEN:
1076 result = get_user(val, ip);
1077 if (result)
1078 return result;
1079 if (val > SG_MAX_CDB_SIZE)
1080 return -ENOMEM;
1081 sfp->next_cmd_len = (val > 0) ? val : 0;
1082 return 0;
1083 case SG_GET_VERSION_NUM:
1084 return put_user(sg_version_num, ip);
1085 case SG_GET_ACCESS_COUNT:
1086 /* faked - we don't have a real access count anymore */
1087 val = (sdp->device ? 1 : 0);
1088 return put_user(val, ip);
1089 case SG_GET_REQUEST_TABLE:
1090 {
1091 sg_req_info_t *rinfo;
1092
1093 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,
1094 GFP_KERNEL);
1095 if (!rinfo)
1096 return -ENOMEM;
1097 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1098 sg_fill_request_table(sfp, rinfo);
1099 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1100 #ifdef CONFIG_COMPAT
1101 if (in_compat_syscall())
1102 result = put_compat_request_table(p, rinfo);
1103 else
1104 #endif
1105 result = copy_to_user(p, rinfo,
1106 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1107 result = result ? -EFAULT : 0;
1108 kfree(rinfo);
1109 return result;
1110 }
1111 case SG_EMULATED_HOST:
1112 if (atomic_read(&sdp->detaching))
1113 return -ENODEV;
1114 return put_user(sdp->device->host->hostt->emulated, ip);
1115 case SCSI_IOCTL_SEND_COMMAND:
1116 if (atomic_read(&sdp->detaching))
1117 return -ENODEV;
1118 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1119 case SG_SET_DEBUG:
1120 result = get_user(val, ip);
1121 if (result)
1122 return result;
1123 sdp->sgdebug = (char) val;
1124 return 0;
1125 case BLKSECTGET:
1126 return put_user(max_sectors_bytes(sdp->device->request_queue),
1127 ip);
1128 case BLKTRACESETUP:
1129 return blk_trace_setup(sdp->device->request_queue,
1130 sdp->disk->disk_name,
1131 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1132 NULL, p);
1133 case BLKTRACESTART:
1134 return blk_trace_startstop(sdp->device->request_queue, 1);
1135 case BLKTRACESTOP:
1136 return blk_trace_startstop(sdp->device->request_queue, 0);
1137 case BLKTRACETEARDOWN:
1138 return blk_trace_remove(sdp->device->request_queue);
1139 case SCSI_IOCTL_GET_IDLUN:
1140 case SCSI_IOCTL_GET_BUS_NUMBER:
1141 case SCSI_IOCTL_PROBE_HOST:
1142 case SG_GET_TRANSFORM:
1143 case SG_SCSI_RESET:
1144 if (atomic_read(&sdp->detaching))
1145 return -ENODEV;
1146 break;
1147 default:
1148 if (read_only)
1149 return -EPERM; /* don't know so take safe approach */
1150 break;
1151 }
1152
1153 result = scsi_ioctl_block_when_processing_errors(sdp->device,
1154 cmd_in, filp->f_flags & O_NDELAY);
1155 if (result)
1156 return result;
1157 return scsi_ioctl(sdp->device, cmd_in, p);
1158 }
1159
1160 #ifdef CONFIG_COMPAT
1161 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1162 {
1163 Sg_device *sdp;
1164 Sg_fd *sfp;
1165 struct scsi_device *sdev;
1166
1167 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1168 return -ENXIO;
1169
1170 sdev = sdp->device;
1171 if (sdev->host->hostt->compat_ioctl) {
1172 int ret;
1173
1174 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1175
1176 return ret;
1177 }
1178
1179 return -ENOIOCTLCMD;
1180 }
1181 #endif
1182
1183 static __poll_t
1184 sg_poll(struct file *filp, poll_table * wait)
1185 {
1186 __poll_t res = 0;
1187 Sg_device *sdp;
1188 Sg_fd *sfp;
1189 Sg_request *srp;
1190 int count = 0;
1191 unsigned long iflags;
1192
1193 sfp = filp->private_data;
1194 if (!sfp)
1195 return EPOLLERR;
1196 sdp = sfp->parentdp;
1197 if (!sdp)
1198 return EPOLLERR;
1199 poll_wait(filp, &sfp->read_wait, wait);
1200 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1201 list_for_each_entry(srp, &sfp->rq_list, entry) {
1202 /* if any read waiting, flag it */
1203 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1204 res = EPOLLIN | EPOLLRDNORM;
1205 ++count;
1206 }
1207 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1208
1209 if (atomic_read(&sdp->detaching))
1210 res |= EPOLLHUP;
1211 else if (!sfp->cmd_q) {
1212 if (0 == count)
1213 res |= EPOLLOUT | EPOLLWRNORM;
1214 } else if (count < SG_MAX_QUEUE)
1215 res |= EPOLLOUT | EPOLLWRNORM;
1216 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1217 "sg_poll: res=0x%x\n", (__force u32) res));
1218 return res;
1219 }
1220
1221 static int
1222 sg_fasync(int fd, struct file *filp, int mode)
1223 {
1224 Sg_device *sdp;
1225 Sg_fd *sfp;
1226
1227 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1228 return -ENXIO;
1229 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1230 "sg_fasync: mode=%d\n", mode));
1231
1232 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1233 }
1234
1235 static vm_fault_t
1236 sg_vma_fault(struct vm_fault *vmf)
1237 {
1238 struct vm_area_struct *vma = vmf->vma;
1239 Sg_fd *sfp;
1240 unsigned long offset, len, sa;
1241 Sg_scatter_hold *rsv_schp;
1242 int k, length;
1243
1244 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1245 return VM_FAULT_SIGBUS;
1246 rsv_schp = &sfp->reserve;
1247 offset = vmf->pgoff << PAGE_SHIFT;
1248 if (offset >= rsv_schp->bufflen)
1249 return VM_FAULT_SIGBUS;
1250 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1251 "sg_vma_fault: offset=%lu, scatg=%d\n",
1252 offset, rsv_schp->k_use_sg));
1253 sa = vma->vm_start;
1254 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1255 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1256 len = vma->vm_end - sa;
1257 len = (len < length) ? len : length;
1258 if (offset < len) {
1259 struct page *page = nth_page(rsv_schp->pages[k],
1260 offset >> PAGE_SHIFT);
1261 get_page(page); /* increment page count */
1262 vmf->page = page;
1263 return 0; /* success */
1264 }
1265 sa += len;
1266 offset -= len;
1267 }
1268
1269 return VM_FAULT_SIGBUS;
1270 }
1271
1272 static const struct vm_operations_struct sg_mmap_vm_ops = {
1273 .fault = sg_vma_fault,
1274 };
1275
1276 static int
1277 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1278 {
1279 Sg_fd *sfp;
1280 unsigned long req_sz, len, sa;
1281 Sg_scatter_hold *rsv_schp;
1282 int k, length;
1283 int ret = 0;
1284
1285 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1286 return -ENXIO;
1287 req_sz = vma->vm_end - vma->vm_start;
1288 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1289 "sg_mmap starting, vm_start=%p, len=%d\n",
1290 (void *) vma->vm_start, (int) req_sz));
1291 if (vma->vm_pgoff)
1292 return -EINVAL; /* want no offset */
1293 rsv_schp = &sfp->reserve;
1294 mutex_lock(&sfp->f_mutex);
1295 if (req_sz > rsv_schp->bufflen) {
1296 ret = -ENOMEM; /* cannot map more than reserved buffer */
1297 goto out;
1298 }
1299
1300 sa = vma->vm_start;
1301 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1302 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1303 len = vma->vm_end - sa;
1304 len = (len < length) ? len : length;
1305 sa += len;
1306 }
1307
1308 sfp->mmap_called = 1;
1309 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1310 vma->vm_private_data = sfp;
1311 vma->vm_ops = &sg_mmap_vm_ops;
1312 out:
1313 mutex_unlock(&sfp->f_mutex);
1314 return ret;
1315 }
1316
1317 static void
1318 sg_rq_end_io_usercontext(struct work_struct *work)
1319 {
1320 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1321 struct sg_fd *sfp = srp->parentfp;
1322
1323 sg_finish_rem_req(srp);
1324 sg_remove_request(sfp, srp);
1325 kref_put(&sfp->f_ref, sg_remove_sfp);
1326 }
1327
1328 /*
1329 * This function is a "bottom half" handler that is called by the mid
1330 * level when a command is completed (or has failed).
1331 */
1332 static void
1333 sg_rq_end_io(struct request *rq, blk_status_t status)
1334 {
1335 struct sg_request *srp = rq->end_io_data;
1336 struct scsi_request *req = scsi_req(rq);
1337 Sg_device *sdp;
1338 Sg_fd *sfp;
1339 unsigned long iflags;
1340 unsigned int ms;
1341 char *sense;
1342 int result, resid, done = 1;
1343
1344 if (WARN_ON(srp->done != 0))
1345 return;
1346
1347 sfp = srp->parentfp;
1348 if (WARN_ON(sfp == NULL))
1349 return;
1350
1351 sdp = sfp->parentdp;
1352 if (unlikely(atomic_read(&sdp->detaching)))
1353 pr_info("%s: device detaching\n", __func__);
1354
1355 sense = req->sense;
1356 result = req->result;
1357 resid = req->resid_len;
1358
1359 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1360 "sg_cmd_done: pack_id=%d, res=0x%x\n",
1361 srp->header.pack_id, result));
1362 srp->header.resid = resid;
1363 ms = jiffies_to_msecs(jiffies);
1364 srp->header.duration = (ms > srp->header.duration) ?
1365 (ms - srp->header.duration) : 0;
1366 if (0 != result) {
1367 struct scsi_sense_hdr sshdr;
1368
1369 srp->header.status = 0xff & result;
1370 srp->header.masked_status = status_byte(result);
1371 srp->header.msg_status = msg_byte(result);
1372 srp->header.host_status = host_byte(result);
1373 srp->header.driver_status = driver_byte(result);
1374 if ((sdp->sgdebug > 0) &&
1375 ((CHECK_CONDITION == srp->header.masked_status) ||
1376 (COMMAND_TERMINATED == srp->header.masked_status)))
1377 __scsi_print_sense(sdp->device, __func__, sense,
1378 SCSI_SENSE_BUFFERSIZE);
1379
1380 /* Following if statement is a patch supplied by Eric Youngdale */
1381 if (driver_byte(result) != 0
1382 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1383 && !scsi_sense_is_deferred(&sshdr)
1384 && sshdr.sense_key == UNIT_ATTENTION
1385 && sdp->device->removable) {
1386 /* Detected possible disc change. Set the bit - this */
1387 /* may be used if there are filesystems using this device */
1388 sdp->device->changed = 1;
1389 }
1390 }
1391
1392 if (req->sense_len)
1393 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE);
1394
1395 /* Rely on write phase to clean out srp status values, so no "else" */
1396
1397 /*
1398 * Free the request as soon as it is complete so that its resources
1399 * can be reused without waiting for userspace to read() the
1400 * result. But keep the associated bio (if any) around until
1401 * blk_rq_unmap_user() can be called from user context.
1402 */
1403 srp->rq = NULL;
1404 scsi_req_free_cmd(scsi_req(rq));
1405 blk_put_request(rq);
1406
1407 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1408 if (unlikely(srp->orphan)) {
1409 if (sfp->keep_orphan)
1410 srp->sg_io_owned = 0;
1411 else
1412 done = 0;
1413 }
1414 srp->done = done;
1415 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1416
1417 if (likely(done)) {
1418 /* Now wake up any sg_read() that is waiting for this
1419 * packet.
1420 */
1421 wake_up_interruptible(&sfp->read_wait);
1422 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1423 kref_put(&sfp->f_ref, sg_remove_sfp);
1424 } else {
1425 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1426 schedule_work(&srp->ew.work);
1427 }
1428 }
1429
1430 static const struct file_operations sg_fops = {
1431 .owner = THIS_MODULE,
1432 .read = sg_read,
1433 .write = sg_write,
1434 .poll = sg_poll,
1435 .unlocked_ioctl = sg_ioctl,
1436 #ifdef CONFIG_COMPAT
1437 .compat_ioctl = sg_compat_ioctl,
1438 #endif
1439 .open = sg_open,
1440 .mmap = sg_mmap,
1441 .release = sg_release,
1442 .fasync = sg_fasync,
1443 .llseek = no_llseek,
1444 };
1445
1446 static struct class *sg_sysfs_class;
1447
1448 static int sg_sysfs_valid = 0;
1449
1450 static Sg_device *
1451 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1452 {
1453 struct request_queue *q = scsidp->request_queue;
1454 Sg_device *sdp;
1455 unsigned long iflags;
1456 int error;
1457 u32 k;
1458
1459 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1460 if (!sdp) {
1461 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1462 "failure\n", __func__);
1463 return ERR_PTR(-ENOMEM);
1464 }
1465
1466 idr_preload(GFP_KERNEL);
1467 write_lock_irqsave(&sg_index_lock, iflags);
1468
1469 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1470 if (error < 0) {
1471 if (error == -ENOSPC) {
1472 sdev_printk(KERN_WARNING, scsidp,
1473 "Unable to attach sg device type=%d, minor number exceeds %d\n",
1474 scsidp->type, SG_MAX_DEVS - 1);
1475 error = -ENODEV;
1476 } else {
1477 sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1478 "allocation Sg_device failure: %d\n",
1479 __func__, error);
1480 }
1481 goto out_unlock;
1482 }
1483 k = error;
1484
1485 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1486 "sg_alloc: dev=%d \n", k));
1487 sprintf(disk->disk_name, "sg%d", k);
1488 disk->first_minor = k;
1489 sdp->disk = disk;
1490 sdp->device = scsidp;
1491 mutex_init(&sdp->open_rel_lock);
1492 INIT_LIST_HEAD(&sdp->sfds);
1493 init_waitqueue_head(&sdp->open_wait);
1494 atomic_set(&sdp->detaching, 0);
1495 rwlock_init(&sdp->sfd_lock);
1496 sdp->sg_tablesize = queue_max_segments(q);
1497 sdp->index = k;
1498 kref_init(&sdp->d_ref);
1499 error = 0;
1500
1501 out_unlock:
1502 write_unlock_irqrestore(&sg_index_lock, iflags);
1503 idr_preload_end();
1504
1505 if (error) {
1506 kfree(sdp);
1507 return ERR_PTR(error);
1508 }
1509 return sdp;
1510 }
1511
1512 static int
1513 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1514 {
1515 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1516 struct gendisk *disk;
1517 Sg_device *sdp = NULL;
1518 struct cdev * cdev = NULL;
1519 int error;
1520 unsigned long iflags;
1521
1522 disk = alloc_disk(1);
1523 if (!disk) {
1524 pr_warn("%s: alloc_disk failed\n", __func__);
1525 return -ENOMEM;
1526 }
1527 disk->major = SCSI_GENERIC_MAJOR;
1528
1529 error = -ENOMEM;
1530 cdev = cdev_alloc();
1531 if (!cdev) {
1532 pr_warn("%s: cdev_alloc failed\n", __func__);
1533 goto out;
1534 }
1535 cdev->owner = THIS_MODULE;
1536 cdev->ops = &sg_fops;
1537
1538 sdp = sg_alloc(disk, scsidp);
1539 if (IS_ERR(sdp)) {
1540 pr_warn("%s: sg_alloc failed\n", __func__);
1541 error = PTR_ERR(sdp);
1542 goto out;
1543 }
1544
1545 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1546 if (error)
1547 goto cdev_add_err;
1548
1549 sdp->cdev = cdev;
1550 if (sg_sysfs_valid) {
1551 struct device *sg_class_member;
1552
1553 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1554 MKDEV(SCSI_GENERIC_MAJOR,
1555 sdp->index),
1556 sdp, "%s", disk->disk_name);
1557 if (IS_ERR(sg_class_member)) {
1558 pr_err("%s: device_create failed\n", __func__);
1559 error = PTR_ERR(sg_class_member);
1560 goto cdev_add_err;
1561 }
1562 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1563 &sg_class_member->kobj, "generic");
1564 if (error)
1565 pr_err("%s: unable to make symlink 'generic' back "
1566 "to sg%d\n", __func__, sdp->index);
1567 } else
1568 pr_warn("%s: sg_sys Invalid\n", __func__);
1569
1570 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1571 "type %d\n", sdp->index, scsidp->type);
1572
1573 dev_set_drvdata(cl_dev, sdp);
1574
1575 return 0;
1576
1577 cdev_add_err:
1578 write_lock_irqsave(&sg_index_lock, iflags);
1579 idr_remove(&sg_index_idr, sdp->index);
1580 write_unlock_irqrestore(&sg_index_lock, iflags);
1581 kfree(sdp);
1582
1583 out:
1584 put_disk(disk);
1585 if (cdev)
1586 cdev_del(cdev);
1587 return error;
1588 }
1589
1590 static void
1591 sg_device_destroy(struct kref *kref)
1592 {
1593 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1594 unsigned long flags;
1595
1596 /* CAUTION! Note that the device can still be found via idr_find()
1597 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1598 * any other cleanup.
1599 */
1600
1601 write_lock_irqsave(&sg_index_lock, flags);
1602 idr_remove(&sg_index_idr, sdp->index);
1603 write_unlock_irqrestore(&sg_index_lock, flags);
1604
1605 SCSI_LOG_TIMEOUT(3,
1606 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
1607
1608 put_disk(sdp->disk);
1609 kfree(sdp);
1610 }
1611
1612 static void
1613 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1614 {
1615 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1616 Sg_device *sdp = dev_get_drvdata(cl_dev);
1617 unsigned long iflags;
1618 Sg_fd *sfp;
1619 int val;
1620
1621 if (!sdp)
1622 return;
1623 /* want sdp->detaching non-zero as soon as possible */
1624 val = atomic_inc_return(&sdp->detaching);
1625 if (val > 1)
1626 return; /* only want to do following once per device */
1627
1628 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1629 "%s\n", __func__));
1630
1631 read_lock_irqsave(&sdp->sfd_lock, iflags);
1632 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1633 wake_up_interruptible_all(&sfp->read_wait);
1634 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1635 }
1636 wake_up_interruptible_all(&sdp->open_wait);
1637 read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1638
1639 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1640 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1641 cdev_del(sdp->cdev);
1642 sdp->cdev = NULL;
1643
1644 kref_put(&sdp->d_ref, sg_device_destroy);
1645 }
1646
1647 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1648 module_param_named(def_reserved_size, def_reserved_size, int,
1649 S_IRUGO | S_IWUSR);
1650 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1651
1652 MODULE_AUTHOR("Douglas Gilbert");
1653 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1654 MODULE_LICENSE("GPL");
1655 MODULE_VERSION(SG_VERSION_STR);
1656 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1657
1658 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1659 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1660 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1661 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1662
1663 static int __init
1664 init_sg(void)
1665 {
1666 int rc;
1667
1668 if (scatter_elem_sz < PAGE_SIZE) {
1669 scatter_elem_sz = PAGE_SIZE;
1670 scatter_elem_sz_prev = scatter_elem_sz;
1671 }
1672 if (def_reserved_size >= 0)
1673 sg_big_buff = def_reserved_size;
1674 else
1675 def_reserved_size = sg_big_buff;
1676
1677 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1678 SG_MAX_DEVS, "sg");
1679 if (rc)
1680 return rc;
1681 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1682 if ( IS_ERR(sg_sysfs_class) ) {
1683 rc = PTR_ERR(sg_sysfs_class);
1684 goto err_out;
1685 }
1686 sg_sysfs_valid = 1;
1687 rc = scsi_register_interface(&sg_interface);
1688 if (0 == rc) {
1689 #ifdef CONFIG_SCSI_PROC_FS
1690 sg_proc_init();
1691 #endif /* CONFIG_SCSI_PROC_FS */
1692 return 0;
1693 }
1694 class_destroy(sg_sysfs_class);
1695 err_out:
1696 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1697 return rc;
1698 }
1699
1700 static void __exit
1701 exit_sg(void)
1702 {
1703 #ifdef CONFIG_SCSI_PROC_FS
1704 remove_proc_subtree("scsi/sg", NULL);
1705 #endif /* CONFIG_SCSI_PROC_FS */
1706 scsi_unregister_interface(&sg_interface);
1707 class_destroy(sg_sysfs_class);
1708 sg_sysfs_valid = 0;
1709 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1710 SG_MAX_DEVS);
1711 idr_destroy(&sg_index_idr);
1712 }
1713
1714 static int
1715 sg_start_req(Sg_request *srp, unsigned char *cmd)
1716 {
1717 int res;
1718 struct request *rq;
1719 struct scsi_request *req;
1720 Sg_fd *sfp = srp->parentfp;
1721 sg_io_hdr_t *hp = &srp->header;
1722 int dxfer_len = (int) hp->dxfer_len;
1723 int dxfer_dir = hp->dxfer_direction;
1724 unsigned int iov_count = hp->iovec_count;
1725 Sg_scatter_hold *req_schp = &srp->data;
1726 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1727 struct request_queue *q = sfp->parentdp->device->request_queue;
1728 struct rq_map_data *md, map_data;
1729 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1730 unsigned char *long_cmdp = NULL;
1731
1732 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1733 "sg_start_req: dxfer_len=%d\n",
1734 dxfer_len));
1735
1736 if (hp->cmd_len > BLK_MAX_CDB) {
1737 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1738 if (!long_cmdp)
1739 return -ENOMEM;
1740 }
1741
1742 /*
1743 * NOTE
1744 *
1745 * With scsi-mq enabled, there are a fixed number of preallocated
1746 * requests equal in number to shost->can_queue. If all of the
1747 * preallocated requests are already in use, then blk_get_request()
1748 * will sleep until an active command completes, freeing up a request.
1749 * Although waiting in an asynchronous interface is less than ideal, we
1750 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might
1751 * not expect an EWOULDBLOCK from this condition.
1752 */
1753 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?
1754 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
1755 if (IS_ERR(rq)) {
1756 kfree(long_cmdp);
1757 return PTR_ERR(rq);
1758 }
1759 req = scsi_req(rq);
1760
1761 if (hp->cmd_len > BLK_MAX_CDB)
1762 req->cmd = long_cmdp;
1763 memcpy(req->cmd, cmd, hp->cmd_len);
1764 req->cmd_len = hp->cmd_len;
1765
1766 srp->rq = rq;
1767 rq->end_io_data = srp;
1768 req->retries = SG_DEFAULT_RETRIES;
1769
1770 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1771 return 0;
1772
1773 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1774 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1775 !sfp->parentdp->device->host->unchecked_isa_dma &&
1776 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1777 md = NULL;
1778 else
1779 md = &map_data;
1780
1781 if (md) {
1782 mutex_lock(&sfp->f_mutex);
1783 if (dxfer_len <= rsv_schp->bufflen &&
1784 !sfp->res_in_use) {
1785 sfp->res_in_use = 1;
1786 sg_link_reserve(sfp, srp, dxfer_len);
1787 } else if (hp->flags & SG_FLAG_MMAP_IO) {
1788 res = -EBUSY; /* sfp->res_in_use == 1 */
1789 if (dxfer_len > rsv_schp->bufflen)
1790 res = -ENOMEM;
1791 mutex_unlock(&sfp->f_mutex);
1792 return res;
1793 } else {
1794 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1795 if (res) {
1796 mutex_unlock(&sfp->f_mutex);
1797 return res;
1798 }
1799 }
1800 mutex_unlock(&sfp->f_mutex);
1801
1802 md->pages = req_schp->pages;
1803 md->page_order = req_schp->page_order;
1804 md->nr_entries = req_schp->k_use_sg;
1805 md->offset = 0;
1806 md->null_mapped = hp->dxferp ? 0 : 1;
1807 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1808 md->from_user = 1;
1809 else
1810 md->from_user = 0;
1811 }
1812
1813 if (iov_count) {
1814 struct iovec *iov = NULL;
1815 struct iov_iter i;
1816
1817 #ifdef CONFIG_COMPAT
1818 if (in_compat_syscall())
1819 res = compat_import_iovec(rw, hp->dxferp, iov_count,
1820 0, &iov, &i);
1821 else
1822 #endif
1823 res = import_iovec(rw, hp->dxferp, iov_count,
1824 0, &iov, &i);
1825 if (res < 0)
1826 return res;
1827
1828 iov_iter_truncate(&i, hp->dxfer_len);
1829 if (!iov_iter_count(&i)) {
1830 kfree(iov);
1831 return -EINVAL;
1832 }
1833
1834 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
1835 kfree(iov);
1836 } else
1837 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1838 hp->dxfer_len, GFP_ATOMIC);
1839
1840 if (!res) {
1841 srp->bio = rq->bio;
1842
1843 if (!md) {
1844 req_schp->dio_in_use = 1;
1845 hp->info |= SG_INFO_DIRECT_IO;
1846 }
1847 }
1848 return res;
1849 }
1850
1851 static int
1852 sg_finish_rem_req(Sg_request *srp)
1853 {
1854 int ret = 0;
1855
1856 Sg_fd *sfp = srp->parentfp;
1857 Sg_scatter_hold *req_schp = &srp->data;
1858
1859 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1860 "sg_finish_rem_req: res_used=%d\n",
1861 (int) srp->res_used));
1862 if (srp->bio)
1863 ret = blk_rq_unmap_user(srp->bio);
1864
1865 if (srp->rq) {
1866 scsi_req_free_cmd(scsi_req(srp->rq));
1867 blk_put_request(srp->rq);
1868 }
1869
1870 if (srp->res_used)
1871 sg_unlink_reserve(sfp, srp);
1872 else
1873 sg_remove_scat(sfp, req_schp);
1874
1875 return ret;
1876 }
1877
1878 static int
1879 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1880 {
1881 int sg_bufflen = tablesize * sizeof(struct page *);
1882 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1883
1884 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1885 if (!schp->pages)
1886 return -ENOMEM;
1887 schp->sglist_len = sg_bufflen;
1888 return tablesize; /* number of scat_gath elements allocated */
1889 }
1890
1891 static int
1892 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1893 {
1894 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1895 int sg_tablesize = sfp->parentdp->sg_tablesize;
1896 int blk_size = buff_size, order;
1897 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;
1898 struct sg_device *sdp = sfp->parentdp;
1899
1900 if (blk_size < 0)
1901 return -EFAULT;
1902 if (0 == blk_size)
1903 ++blk_size; /* don't know why */
1904 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1905 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1906 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1907 "sg_build_indirect: buff_size=%d, blk_size=%d\n",
1908 buff_size, blk_size));
1909
1910 /* N.B. ret_sz carried into this block ... */
1911 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1912 if (mx_sc_elems < 0)
1913 return mx_sc_elems; /* most likely -ENOMEM */
1914
1915 num = scatter_elem_sz;
1916 if (unlikely(num != scatter_elem_sz_prev)) {
1917 if (num < PAGE_SIZE) {
1918 scatter_elem_sz = PAGE_SIZE;
1919 scatter_elem_sz_prev = PAGE_SIZE;
1920 } else
1921 scatter_elem_sz_prev = num;
1922 }
1923
1924 if (sdp->device->host->unchecked_isa_dma)
1925 gfp_mask |= GFP_DMA;
1926
1927 order = get_order(num);
1928 retry:
1929 ret_sz = 1 << (PAGE_SHIFT + order);
1930
1931 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1932 k++, rem_sz -= ret_sz) {
1933
1934 num = (rem_sz > scatter_elem_sz_prev) ?
1935 scatter_elem_sz_prev : rem_sz;
1936
1937 schp->pages[k] = alloc_pages(gfp_mask, order);
1938 if (!schp->pages[k])
1939 goto out;
1940
1941 if (num == scatter_elem_sz_prev) {
1942 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1943 scatter_elem_sz = ret_sz;
1944 scatter_elem_sz_prev = ret_sz;
1945 }
1946 }
1947
1948 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1949 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1950 k, num, ret_sz));
1951 } /* end of for loop */
1952
1953 schp->page_order = order;
1954 schp->k_use_sg = k;
1955 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1956 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1957 k, rem_sz));
1958
1959 schp->bufflen = blk_size;
1960 if (rem_sz > 0) /* must have failed */
1961 return -ENOMEM;
1962 return 0;
1963 out:
1964 for (i = 0; i < k; i++)
1965 __free_pages(schp->pages[i], order);
1966
1967 if (--order >= 0)
1968 goto retry;
1969
1970 return -ENOMEM;
1971 }
1972
1973 static void
1974 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1975 {
1976 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1977 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1978 if (schp->pages && schp->sglist_len > 0) {
1979 if (!schp->dio_in_use) {
1980 int k;
1981
1982 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1983 SCSI_LOG_TIMEOUT(5,
1984 sg_printk(KERN_INFO, sfp->parentdp,
1985 "sg_remove_scat: k=%d, pg=0x%p\n",
1986 k, schp->pages[k]));
1987 __free_pages(schp->pages[k], schp->page_order);
1988 }
1989
1990 kfree(schp->pages);
1991 }
1992 }
1993 memset(schp, 0, sizeof (*schp));
1994 }
1995
1996 static int
1997 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1998 {
1999 Sg_scatter_hold *schp = &srp->data;
2000 int k, num;
2001
2002 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2003 "sg_read_oxfer: num_read_xfer=%d\n",
2004 num_read_xfer));
2005 if ((!outp) || (num_read_xfer <= 0))
2006 return 0;
2007
2008 num = 1 << (PAGE_SHIFT + schp->page_order);
2009 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
2010 if (num > num_read_xfer) {
2011 if (copy_to_user(outp, page_address(schp->pages[k]),
2012 num_read_xfer))
2013 return -EFAULT;
2014 break;
2015 } else {
2016 if (copy_to_user(outp, page_address(schp->pages[k]),
2017 num))
2018 return -EFAULT;
2019 num_read_xfer -= num;
2020 if (num_read_xfer <= 0)
2021 break;
2022 outp += num;
2023 }
2024 }
2025
2026 return 0;
2027 }
2028
2029 static void
2030 sg_build_reserve(Sg_fd * sfp, int req_size)
2031 {
2032 Sg_scatter_hold *schp = &sfp->reserve;
2033
2034 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2035 "sg_build_reserve: req_size=%d\n", req_size));
2036 do {
2037 if (req_size < PAGE_SIZE)
2038 req_size = PAGE_SIZE;
2039 if (0 == sg_build_indirect(schp, sfp, req_size))
2040 return;
2041 else
2042 sg_remove_scat(sfp, schp);
2043 req_size >>= 1; /* divide by 2 */
2044 } while (req_size > (PAGE_SIZE / 2));
2045 }
2046
2047 static void
2048 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2049 {
2050 Sg_scatter_hold *req_schp = &srp->data;
2051 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2052 int k, num, rem;
2053
2054 srp->res_used = 1;
2055 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
2056 "sg_link_reserve: size=%d\n", size));
2057 rem = size;
2058
2059 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
2060 for (k = 0; k < rsv_schp->k_use_sg; k++) {
2061 if (rem <= num) {
2062 req_schp->k_use_sg = k + 1;
2063 req_schp->sglist_len = rsv_schp->sglist_len;
2064 req_schp->pages = rsv_schp->pages;
2065
2066 req_schp->bufflen = size;
2067 req_schp->page_order = rsv_schp->page_order;
2068 break;
2069 } else
2070 rem -= num;
2071 }
2072
2073 if (k >= rsv_schp->k_use_sg)
2074 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2075 "sg_link_reserve: BAD size\n"));
2076 }
2077
2078 static void
2079 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2080 {
2081 Sg_scatter_hold *req_schp = &srp->data;
2082
2083 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2084 "sg_unlink_reserve: req->k_use_sg=%d\n",
2085 (int) req_schp->k_use_sg));
2086 req_schp->k_use_sg = 0;
2087 req_schp->bufflen = 0;
2088 req_schp->pages = NULL;
2089 req_schp->page_order = 0;
2090 req_schp->sglist_len = 0;
2091 srp->res_used = 0;
2092 /* Called without mutex lock to avoid deadlock */
2093 sfp->res_in_use = 0;
2094 }
2095
2096 static Sg_request *
2097 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2098 {
2099 Sg_request *resp;
2100 unsigned long iflags;
2101
2102 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2103 list_for_each_entry(resp, &sfp->rq_list, entry) {
2104 /* look for requests that are ready + not SG_IO owned */
2105 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2106 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2107 resp->done = 2; /* guard against other readers */
2108 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2109 return resp;
2110 }
2111 }
2112 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2113 return NULL;
2114 }
2115
2116 /* always adds to end of list */
2117 static Sg_request *
2118 sg_add_request(Sg_fd * sfp)
2119 {
2120 int k;
2121 unsigned long iflags;
2122 Sg_request *rp = sfp->req_arr;
2123
2124 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2125 if (!list_empty(&sfp->rq_list)) {
2126 if (!sfp->cmd_q)
2127 goto out_unlock;
2128
2129 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2130 if (!rp->parentfp)
2131 break;
2132 }
2133 if (k >= SG_MAX_QUEUE)
2134 goto out_unlock;
2135 }
2136 memset(rp, 0, sizeof (Sg_request));
2137 rp->parentfp = sfp;
2138 rp->header.duration = jiffies_to_msecs(jiffies);
2139 list_add_tail(&rp->entry, &sfp->rq_list);
2140 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2141 return rp;
2142 out_unlock:
2143 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2144 return NULL;
2145 }
2146
2147 /* Return of 1 for found; 0 for not found */
2148 static int
2149 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2150 {
2151 unsigned long iflags;
2152 int res = 0;
2153
2154 if (!sfp || !srp || list_empty(&sfp->rq_list))
2155 return res;
2156 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2157 if (!list_empty(&srp->entry)) {
2158 list_del(&srp->entry);
2159 srp->parentfp = NULL;
2160 res = 1;
2161 }
2162 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2163 return res;
2164 }
2165
2166 static Sg_fd *
2167 sg_add_sfp(Sg_device * sdp)
2168 {
2169 Sg_fd *sfp;
2170 unsigned long iflags;
2171 int bufflen;
2172
2173 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2174 if (!sfp)
2175 return ERR_PTR(-ENOMEM);
2176
2177 init_waitqueue_head(&sfp->read_wait);
2178 rwlock_init(&sfp->rq_list_lock);
2179 INIT_LIST_HEAD(&sfp->rq_list);
2180 kref_init(&sfp->f_ref);
2181 mutex_init(&sfp->f_mutex);
2182 sfp->timeout = SG_DEFAULT_TIMEOUT;
2183 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2184 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2185 sfp->cmd_q = SG_DEF_COMMAND_Q;
2186 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2187 sfp->parentdp = sdp;
2188 write_lock_irqsave(&sdp->sfd_lock, iflags);
2189 if (atomic_read(&sdp->detaching)) {
2190 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2191 kfree(sfp);
2192 return ERR_PTR(-ENODEV);
2193 }
2194 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2195 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2196 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2197 "sg_add_sfp: sfp=0x%p\n", sfp));
2198 if (unlikely(sg_big_buff != def_reserved_size))
2199 sg_big_buff = def_reserved_size;
2200
2201 bufflen = min_t(int, sg_big_buff,
2202 max_sectors_bytes(sdp->device->request_queue));
2203 sg_build_reserve(sfp, bufflen);
2204 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2205 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2206 sfp->reserve.bufflen,
2207 sfp->reserve.k_use_sg));
2208
2209 kref_get(&sdp->d_ref);
2210 __module_get(THIS_MODULE);
2211 return sfp;
2212 }
2213
2214 static void
2215 sg_remove_sfp_usercontext(struct work_struct *work)
2216 {
2217 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2218 struct sg_device *sdp = sfp->parentdp;
2219 Sg_request *srp;
2220 unsigned long iflags;
2221
2222 /* Cleanup any responses which were never read(). */
2223 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2224 while (!list_empty(&sfp->rq_list)) {
2225 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);
2226 sg_finish_rem_req(srp);
2227 list_del(&srp->entry);
2228 srp->parentfp = NULL;
2229 }
2230 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2231
2232 if (sfp->reserve.bufflen > 0) {
2233 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2234 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2235 (int) sfp->reserve.bufflen,
2236 (int) sfp->reserve.k_use_sg));
2237 sg_remove_scat(sfp, &sfp->reserve);
2238 }
2239
2240 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2241 "sg_remove_sfp: sfp=0x%p\n", sfp));
2242 kfree(sfp);
2243
2244 scsi_device_put(sdp->device);
2245 kref_put(&sdp->d_ref, sg_device_destroy);
2246 module_put(THIS_MODULE);
2247 }
2248
2249 static void
2250 sg_remove_sfp(struct kref *kref)
2251 {
2252 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2253 struct sg_device *sdp = sfp->parentdp;
2254 unsigned long iflags;
2255
2256 write_lock_irqsave(&sdp->sfd_lock, iflags);
2257 list_del(&sfp->sfd_siblings);
2258 write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2259
2260 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2261 schedule_work(&sfp->ew.work);
2262 }
2263
2264 #ifdef CONFIG_SCSI_PROC_FS
2265 static int
2266 sg_idr_max_id(int id, void *p, void *data)
2267 {
2268 int *k = data;
2269
2270 if (*k < id)
2271 *k = id;
2272
2273 return 0;
2274 }
2275
2276 static int
2277 sg_last_dev(void)
2278 {
2279 int k = -1;
2280 unsigned long iflags;
2281
2282 read_lock_irqsave(&sg_index_lock, iflags);
2283 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2284 read_unlock_irqrestore(&sg_index_lock, iflags);
2285 return k + 1; /* origin 1 */
2286 }
2287 #endif
2288
2289 /* must be called with sg_index_lock held */
2290 static Sg_device *sg_lookup_dev(int dev)
2291 {
2292 return idr_find(&sg_index_idr, dev);
2293 }
2294
2295 static Sg_device *
2296 sg_get_dev(int dev)
2297 {
2298 struct sg_device *sdp;
2299 unsigned long flags;
2300
2301 read_lock_irqsave(&sg_index_lock, flags);
2302 sdp = sg_lookup_dev(dev);
2303 if (!sdp)
2304 sdp = ERR_PTR(-ENXIO);
2305 else if (atomic_read(&sdp->detaching)) {
2306 /* If sdp->detaching, then the refcount may already be 0, in
2307 * which case it would be a bug to do kref_get().
2308 */
2309 sdp = ERR_PTR(-ENODEV);
2310 } else
2311 kref_get(&sdp->d_ref);
2312 read_unlock_irqrestore(&sg_index_lock, flags);
2313
2314 return sdp;
2315 }
2316
2317 #ifdef CONFIG_SCSI_PROC_FS
2318 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2319
2320 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2321 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2322 size_t count, loff_t *off);
2323 static const struct file_operations adio_fops = {
2324 .owner = THIS_MODULE,
2325 .open = sg_proc_single_open_adio,
2326 .read = seq_read,
2327 .llseek = seq_lseek,
2328 .write = sg_proc_write_adio,
2329 .release = single_release,
2330 };
2331
2332 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2333 static ssize_t sg_proc_write_dressz(struct file *filp,
2334 const char __user *buffer, size_t count, loff_t *off);
2335 static const struct file_operations dressz_fops = {
2336 .owner = THIS_MODULE,
2337 .open = sg_proc_single_open_dressz,
2338 .read = seq_read,
2339 .llseek = seq_lseek,
2340 .write = sg_proc_write_dressz,
2341 .release = single_release,
2342 };
2343
2344 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2345 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2346 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2347 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2348 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2349 static void dev_seq_stop(struct seq_file *s, void *v);
2350 static const struct seq_operations dev_seq_ops = {
2351 .start = dev_seq_start,
2352 .next = dev_seq_next,
2353 .stop = dev_seq_stop,
2354 .show = sg_proc_seq_show_dev,
2355 };
2356
2357 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2358 static const struct seq_operations devstrs_seq_ops = {
2359 .start = dev_seq_start,
2360 .next = dev_seq_next,
2361 .stop = dev_seq_stop,
2362 .show = sg_proc_seq_show_devstrs,
2363 };
2364
2365 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2366 static const struct seq_operations debug_seq_ops = {
2367 .start = dev_seq_start,
2368 .next = dev_seq_next,
2369 .stop = dev_seq_stop,
2370 .show = sg_proc_seq_show_debug,
2371 };
2372
2373 static int
2374 sg_proc_init(void)
2375 {
2376 struct proc_dir_entry *p;
2377
2378 p = proc_mkdir("scsi/sg", NULL);
2379 if (!p)
2380 return 1;
2381
2382 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_fops);
2383 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);
2384 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_fops);
2385 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr);
2386 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops);
2387 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops);
2388 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version);
2389 return 0;
2390 }
2391
2392
2393 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2394 {
2395 seq_printf(s, "%d\n", *((int *)s->private));
2396 return 0;
2397 }
2398
2399 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2400 {
2401 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2402 }
2403
2404 static ssize_t
2405 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2406 size_t count, loff_t *off)
2407 {
2408 int err;
2409 unsigned long num;
2410
2411 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2412 return -EACCES;
2413 err = kstrtoul_from_user(buffer, count, 0, &num);
2414 if (err)
2415 return err;
2416 sg_allow_dio = num ? 1 : 0;
2417 return count;
2418 }
2419
2420 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2421 {
2422 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2423 }
2424
2425 static ssize_t
2426 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2427 size_t count, loff_t *off)
2428 {
2429 int err;
2430 unsigned long k = ULONG_MAX;
2431
2432 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2433 return -EACCES;
2434
2435 err = kstrtoul_from_user(buffer, count, 0, &k);
2436 if (err)
2437 return err;
2438 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2439 sg_big_buff = k;
2440 return count;
2441 }
2442 return -ERANGE;
2443 }
2444
2445 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2446 {
2447 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2448 sg_version_date);
2449 return 0;
2450 }
2451
2452 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2453 {
2454 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
2455 return 0;
2456 }
2457
2458 struct sg_proc_deviter {
2459 loff_t index;
2460 size_t max;
2461 };
2462
2463 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2464 {
2465 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2466
2467 s->private = it;
2468 if (! it)
2469 return NULL;
2470
2471 it->index = *pos;
2472 it->max = sg_last_dev();
2473 if (it->index >= it->max)
2474 return NULL;
2475 return it;
2476 }
2477
2478 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2479 {
2480 struct sg_proc_deviter * it = s->private;
2481
2482 *pos = ++it->index;
2483 return (it->index < it->max) ? it : NULL;
2484 }
2485
2486 static void dev_seq_stop(struct seq_file *s, void *v)
2487 {
2488 kfree(s->private);
2489 }
2490
2491 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2492 {
2493 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2494 Sg_device *sdp;
2495 struct scsi_device *scsidp;
2496 unsigned long iflags;
2497
2498 read_lock_irqsave(&sg_index_lock, iflags);
2499 sdp = it ? sg_lookup_dev(it->index) : NULL;
2500 if ((NULL == sdp) || (NULL == sdp->device) ||
2501 (atomic_read(&sdp->detaching)))
2502 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2503 else {
2504 scsidp = sdp->device;
2505 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2506 scsidp->host->host_no, scsidp->channel,
2507 scsidp->id, scsidp->lun, (int) scsidp->type,
2508 1,
2509 (int) scsidp->queue_depth,
2510 (int) atomic_read(&scsidp->device_busy),
2511 (int) scsi_device_online(scsidp));
2512 }
2513 read_unlock_irqrestore(&sg_index_lock, iflags);
2514 return 0;
2515 }
2516
2517 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2518 {
2519 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2520 Sg_device *sdp;
2521 struct scsi_device *scsidp;
2522 unsigned long iflags;
2523
2524 read_lock_irqsave(&sg_index_lock, iflags);
2525 sdp = it ? sg_lookup_dev(it->index) : NULL;
2526 scsidp = sdp ? sdp->device : NULL;
2527 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2528 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2529 scsidp->vendor, scsidp->model, scsidp->rev);
2530 else
2531 seq_puts(s, "<no active device>\n");
2532 read_unlock_irqrestore(&sg_index_lock, iflags);
2533 return 0;
2534 }
2535
2536 /* must be called while holding sg_index_lock */
2537 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2538 {
2539 int k, new_interface, blen, usg;
2540 Sg_request *srp;
2541 Sg_fd *fp;
2542 const sg_io_hdr_t *hp;
2543 const char * cp;
2544 unsigned int ms;
2545
2546 k = 0;
2547 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2548 k++;
2549 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2550 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2551 "(res)sgat=%d low_dma=%d\n", k,
2552 jiffies_to_msecs(fp->timeout),
2553 fp->reserve.bufflen,
2554 (int) fp->reserve.k_use_sg,
2555 (int) sdp->device->host->unchecked_isa_dma);
2556 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2557 (int) fp->cmd_q, (int) fp->force_packid,
2558 (int) fp->keep_orphan);
2559 list_for_each_entry(srp, &fp->rq_list, entry) {
2560 hp = &srp->header;
2561 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2562 if (srp->res_used) {
2563 if (new_interface &&
2564 (SG_FLAG_MMAP_IO & hp->flags))
2565 cp = " mmap>> ";
2566 else
2567 cp = " rb>> ";
2568 } else {
2569 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2570 cp = " dio>> ";
2571 else
2572 cp = " ";
2573 }
2574 seq_puts(s, cp);
2575 blen = srp->data.bufflen;
2576 usg = srp->data.k_use_sg;
2577 seq_puts(s, srp->done ?
2578 ((1 == srp->done) ? "rcv:" : "fin:")
2579 : "act:");
2580 seq_printf(s, " id=%d blen=%d",
2581 srp->header.pack_id, blen);
2582 if (srp->done)
2583 seq_printf(s, " dur=%d", hp->duration);
2584 else {
2585 ms = jiffies_to_msecs(jiffies);
2586 seq_printf(s, " t_o/elap=%d/%d",
2587 (new_interface ? hp->timeout :
2588 jiffies_to_msecs(fp->timeout)),
2589 (ms > hp->duration ? ms - hp->duration : 0));
2590 }
2591 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2592 (int) srp->data.cmd_opcode);
2593 }
2594 if (list_empty(&fp->rq_list))
2595 seq_puts(s, " No requests active\n");
2596 read_unlock(&fp->rq_list_lock);
2597 }
2598 }
2599
2600 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2601 {
2602 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2603 Sg_device *sdp;
2604 unsigned long iflags;
2605
2606 if (it && (0 == it->index))
2607 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",
2608 (int)it->max, sg_big_buff);
2609
2610 read_lock_irqsave(&sg_index_lock, iflags);
2611 sdp = it ? sg_lookup_dev(it->index) : NULL;
2612 if (NULL == sdp)
2613 goto skip;
2614 read_lock(&sdp->sfd_lock);
2615 if (!list_empty(&sdp->sfds)) {
2616 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2617 if (atomic_read(&sdp->detaching))
2618 seq_puts(s, "detaching pending close ");
2619 else if (sdp->device) {
2620 struct scsi_device *scsidp = sdp->device;
2621
2622 seq_printf(s, "%d:%d:%d:%llu em=%d",
2623 scsidp->host->host_no,
2624 scsidp->channel, scsidp->id,
2625 scsidp->lun,
2626 scsidp->host->hostt->emulated);
2627 }
2628 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2629 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2630 sg_proc_debug_helper(s, sdp);
2631 }
2632 read_unlock(&sdp->sfd_lock);
2633 skip:
2634 read_unlock_irqrestore(&sg_index_lock, iflags);
2635 return 0;
2636 }
2637
2638 #endif /* CONFIG_SCSI_PROC_FS */
2639
2640 module_init(init_sg);
2641 module_exit(exit_sg);
Linux with added FPC-III support