block: get rid of queue-private command filter
[linux-2.6.git] / drivers / scsi / sg.c
1 /*
2  *  History:
3  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
4  *           to allow user process control of SCSI devices.
5  *  Development Sponsored by Killy Corp. NY NY
6  *
7  * Original driver (sg.c):
8  *        Copyright (C) 1992 Lawrence Foard
9  * Version 2 and 3 extensions to driver:
10  *        Copyright (C) 1998 - 2005 Douglas Gilbert
11  *
12  *  Modified  19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Devfs support
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2, or (at your option)
17  * any later version.
18  *
19  */
20
21 static int sg_version_num = 30534;      /* 2 digits for each component */
22 #define SG_VERSION_STR "3.5.34"
23
24 /*
25  *  D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
26  *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
27  *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
28  *        (otherwise the macros compile to empty statements).
29  *
30  */
31 #include <linux/module.h>
32
33 #include <linux/fs.h>
34 #include <linux/kernel.h>
35 #include <linux/sched.h>
36 #include <linux/string.h>
37 #include <linux/mm.h>
38 #include <linux/errno.h>
39 #include <linux/mtio.h>
40 #include <linux/ioctl.h>
41 #include <linux/fcntl.h>
42 #include <linux/init.h>
43 #include <linux/poll.h>
44 #include <linux/moduleparam.h>
45 #include <linux/cdev.h>
46 #include <linux/idr.h>
47 #include <linux/seq_file.h>
48 #include <linux/blkdev.h>
49 #include <linux/delay.h>
50 #include <linux/blktrace_api.h>
51 #include <linux/smp_lock.h>
52
53 #include "scsi.h"
54 #include <scsi/scsi_dbg.h>
55 #include <scsi/scsi_host.h>
56 #include <scsi/scsi_driver.h>
57 #include <scsi/scsi_ioctl.h>
58 #include <scsi/sg.h>
59
60 #include "scsi_logging.h"
61
62 #ifdef CONFIG_SCSI_PROC_FS
63 #include <linux/proc_fs.h>
64 static char *sg_version_date = "20061027";
65
66 static int sg_proc_init(void);
67 static void sg_proc_cleanup(void);
68 #endif
69
70 #define SG_ALLOW_DIO_DEF 0
71
72 #define SG_MAX_DEVS 32768
73
74 /*
75  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
76  * Then when using 32 bit integers x * m may overflow during the calculation.
77  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
78  * calculates the same, but prevents the overflow when both m and d
79  * are "small" numbers (like HZ and USER_HZ).
80  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
81  * in 32 bits.
82  */
83 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
84
85 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
86
87 int sg_big_buff = SG_DEF_RESERVED_SIZE;
88 /* N.B. This variable is readable and writeable via
89    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
90    of this size (or less if there is not enough memory) will be reserved
91    for use by this file descriptor. [Deprecated usage: this variable is also
92    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
93    the kernel (i.e. it is not a module).] */
94 static int def_reserved_size = -1;      /* picks up init parameter */
95 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
96
97 static int scatter_elem_sz = SG_SCATTER_SZ;
98 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
99
100 #define SG_SECTOR_SZ 512
101
102 static int sg_add(struct device *, struct class_interface *);
103 static void sg_remove(struct device *, struct class_interface *);
104
105 static DEFINE_IDR(sg_index_idr);
106 static DEFINE_RWLOCK(sg_index_lock);    /* Also used to lock
107                                                            file descriptor list for device */
108
109 static struct class_interface sg_interface = {
110         .add_dev        = sg_add,
111         .remove_dev     = sg_remove,
112 };
113
114 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
115         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
116         unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
117         unsigned bufflen;       /* Size of (aggregate) data buffer */
118         struct page **pages;
119         int page_order;
120         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
121         unsigned char cmd_opcode; /* first byte of command */
122 } Sg_scatter_hold;
123
124 struct sg_device;               /* forward declarations */
125 struct sg_fd;
126
127 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
128         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
129         struct sg_fd *parentfp; /* NULL -> not in use */
130         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
131         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
132         unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
133         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
134         char orphan;            /* 1 -> drop on sight, 0 -> normal */
135         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
136         volatile char done;     /* 0->before bh, 1->before read, 2->read */
137         struct request *rq;
138         struct bio *bio;
139         struct execute_work ew;
140 } Sg_request;
141
142 typedef struct sg_fd {          /* holds the state of a file descriptor */
143         struct list_head sfd_siblings;
144         struct sg_device *parentdp;     /* owning device */
145         wait_queue_head_t read_wait;    /* queue read until command done */
146         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
147         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
148         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
149         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
150         unsigned save_scat_len; /* original length of trunc. scat. element */
151         Sg_request *headrp;     /* head of request slist, NULL->empty */
152         struct fasync_struct *async_qp; /* used by asynchronous notification */
153         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
154         char low_dma;           /* as in parent but possibly overridden to 1 */
155         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
156         volatile char closed;   /* 1 -> fd closed but request(s) outstanding */
157         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
158         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
159         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
160         char mmap_called;       /* 0 -> mmap() never called on this fd */
161         struct kref f_ref;
162         struct execute_work ew;
163 } Sg_fd;
164
165 typedef struct sg_device { /* holds the state of each scsi generic device */
166         struct scsi_device *device;
167         wait_queue_head_t o_excl_wait;  /* queue open() when O_EXCL in use */
168         int sg_tablesize;       /* adapter's max scatter-gather table size */
169         u32 index;              /* device index number */
170         struct list_head sfds;
171         volatile char detached; /* 0->attached, 1->detached pending removal */
172         volatile char exclude;  /* opened for exclusive access */
173         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
174         struct gendisk *disk;
175         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
176         struct kref d_ref;
177 } Sg_device;
178
179 /* tasklet or soft irq callback */
180 static void sg_rq_end_io(struct request *rq, int uptodate);
181 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
182 static int sg_finish_rem_req(Sg_request * srp);
183 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
184 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
185                            Sg_request * srp);
186 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
187                         const char __user *buf, size_t count, int blocking,
188                         int read_only, int sg_io_owned, Sg_request **o_srp);
189 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
190                            unsigned char *cmnd, int timeout, int blocking);
191 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
192 static void sg_remove_scat(Sg_scatter_hold * schp);
193 static void sg_build_reserve(Sg_fd * sfp, int req_size);
194 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
195 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
196 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
197 static void sg_remove_sfp(struct kref *);
198 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
199 static Sg_request *sg_add_request(Sg_fd * sfp);
200 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
201 static int sg_res_in_use(Sg_fd * sfp);
202 static Sg_device *sg_get_dev(int dev);
203 static void sg_put_dev(Sg_device *sdp);
204
205 #define SZ_SG_HEADER sizeof(struct sg_header)
206 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
207 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
208 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
209
210 static int sg_allow_access(struct file *filp, unsigned char *cmd)
211 {
212         struct sg_fd *sfp = (struct sg_fd *)filp->private_data;
213
214         if (sfp->parentdp->device->type == TYPE_SCANNER)
215                 return 0;
216
217         return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
218 }
219
220 static int
221 sg_open(struct inode *inode, struct file *filp)
222 {
223         int dev = iminor(inode);
224         int flags = filp->f_flags;
225         struct request_queue *q;
226         Sg_device *sdp;
227         Sg_fd *sfp;
228         int res;
229         int retval;
230
231         lock_kernel();
232         nonseekable_open(inode, filp);
233         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
234         sdp = sg_get_dev(dev);
235         if (IS_ERR(sdp)) {
236                 retval = PTR_ERR(sdp);
237                 sdp = NULL;
238                 goto sg_put;
239         }
240
241         /* This driver's module count bumped by fops_get in <linux/fs.h> */
242         /* Prevent the device driver from vanishing while we sleep */
243         retval = scsi_device_get(sdp->device);
244         if (retval)
245                 goto sg_put;
246
247         if (!((flags & O_NONBLOCK) ||
248               scsi_block_when_processing_errors(sdp->device))) {
249                 retval = -ENXIO;
250                 /* we are in error recovery for this device */
251                 goto error_out;
252         }
253
254         if (flags & O_EXCL) {
255                 if (O_RDONLY == (flags & O_ACCMODE)) {
256                         retval = -EPERM; /* Can't lock it with read only access */
257                         goto error_out;
258                 }
259                 if (!list_empty(&sdp->sfds) && (flags & O_NONBLOCK)) {
260                         retval = -EBUSY;
261                         goto error_out;
262                 }
263                 res = 0;
264                 __wait_event_interruptible(sdp->o_excl_wait,
265                                            ((!list_empty(&sdp->sfds) || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
266                 if (res) {
267                         retval = res;   /* -ERESTARTSYS because signal hit process */
268                         goto error_out;
269                 }
270         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
271                 if (flags & O_NONBLOCK) {
272                         retval = -EBUSY;
273                         goto error_out;
274                 }
275                 res = 0;
276                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
277                                            res);
278                 if (res) {
279                         retval = res;   /* -ERESTARTSYS because signal hit process */
280                         goto error_out;
281                 }
282         }
283         if (sdp->detached) {
284                 retval = -ENODEV;
285                 goto error_out;
286         }
287         if (list_empty(&sdp->sfds)) {   /* no existing opens on this device */
288                 sdp->sgdebug = 0;
289                 q = sdp->device->request_queue;
290                 sdp->sg_tablesize = min(queue_max_hw_segments(q),
291                                         queue_max_phys_segments(q));
292         }
293         if ((sfp = sg_add_sfp(sdp, dev)))
294                 filp->private_data = sfp;
295         else {
296                 if (flags & O_EXCL) {
297                         sdp->exclude = 0;       /* undo if error */
298                         wake_up_interruptible(&sdp->o_excl_wait);
299                 }
300                 retval = -ENOMEM;
301                 goto error_out;
302         }
303         retval = 0;
304 error_out:
305         if (retval)
306                 scsi_device_put(sdp->device);
307 sg_put:
308         if (sdp)
309                 sg_put_dev(sdp);
310         unlock_kernel();
311         return retval;
312 }
313
314 /* Following function was formerly called 'sg_close' */
315 static int
316 sg_release(struct inode *inode, struct file *filp)
317 {
318         Sg_device *sdp;
319         Sg_fd *sfp;
320
321         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
322                 return -ENXIO;
323         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
324
325         sfp->closed = 1;
326
327         sdp->exclude = 0;
328         wake_up_interruptible(&sdp->o_excl_wait);
329
330         kref_put(&sfp->f_ref, sg_remove_sfp);
331         return 0;
332 }
333
334 static ssize_t
335 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
336 {
337         Sg_device *sdp;
338         Sg_fd *sfp;
339         Sg_request *srp;
340         int req_pack_id = -1;
341         sg_io_hdr_t *hp;
342         struct sg_header *old_hdr = NULL;
343         int retval = 0;
344
345         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
346                 return -ENXIO;
347         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
348                                    sdp->disk->disk_name, (int) count));
349
350         if (!access_ok(VERIFY_WRITE, buf, count))
351                 return -EFAULT;
352         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
353                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
354                 if (!old_hdr)
355                         return -ENOMEM;
356                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
357                         retval = -EFAULT;
358                         goto free_old_hdr;
359                 }
360                 if (old_hdr->reply_len < 0) {
361                         if (count >= SZ_SG_IO_HDR) {
362                                 sg_io_hdr_t *new_hdr;
363                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
364                                 if (!new_hdr) {
365                                         retval = -ENOMEM;
366                                         goto free_old_hdr;
367                                 }
368                                 retval =__copy_from_user
369                                     (new_hdr, buf, SZ_SG_IO_HDR);
370                                 req_pack_id = new_hdr->pack_id;
371                                 kfree(new_hdr);
372                                 if (retval) {
373                                         retval = -EFAULT;
374                                         goto free_old_hdr;
375                                 }
376                         }
377                 } else
378                         req_pack_id = old_hdr->pack_id;
379         }
380         srp = sg_get_rq_mark(sfp, req_pack_id);
381         if (!srp) {             /* now wait on packet to arrive */
382                 if (sdp->detached) {
383                         retval = -ENODEV;
384                         goto free_old_hdr;
385                 }
386                 if (filp->f_flags & O_NONBLOCK) {
387                         retval = -EAGAIN;
388                         goto free_old_hdr;
389                 }
390                 while (1) {
391                         retval = 0; /* following macro beats race condition */
392                         __wait_event_interruptible(sfp->read_wait,
393                                 (sdp->detached ||
394                                 (srp = sg_get_rq_mark(sfp, req_pack_id))), 
395                                 retval);
396                         if (sdp->detached) {
397                                 retval = -ENODEV;
398                                 goto free_old_hdr;
399                         }
400                         if (0 == retval)
401                                 break;
402
403                         /* -ERESTARTSYS as signal hit process */
404                         goto free_old_hdr;
405                 }
406         }
407         if (srp->header.interface_id != '\0') {
408                 retval = sg_new_read(sfp, buf, count, srp);
409                 goto free_old_hdr;
410         }
411
412         hp = &srp->header;
413         if (old_hdr == NULL) {
414                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
415                 if (! old_hdr) {
416                         retval = -ENOMEM;
417                         goto free_old_hdr;
418                 }
419         }
420         memset(old_hdr, 0, SZ_SG_HEADER);
421         old_hdr->reply_len = (int) hp->timeout;
422         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
423         old_hdr->pack_id = hp->pack_id;
424         old_hdr->twelve_byte =
425             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
426         old_hdr->target_status = hp->masked_status;
427         old_hdr->host_status = hp->host_status;
428         old_hdr->driver_status = hp->driver_status;
429         if ((CHECK_CONDITION & hp->masked_status) ||
430             (DRIVER_SENSE & hp->driver_status))
431                 memcpy(old_hdr->sense_buffer, srp->sense_b,
432                        sizeof (old_hdr->sense_buffer));
433         switch (hp->host_status) {
434         /* This setup of 'result' is for backward compatibility and is best
435            ignored by the user who should use target, host + driver status */
436         case DID_OK:
437         case DID_PASSTHROUGH:
438         case DID_SOFT_ERROR:
439                 old_hdr->result = 0;
440                 break;
441         case DID_NO_CONNECT:
442         case DID_BUS_BUSY:
443         case DID_TIME_OUT:
444                 old_hdr->result = EBUSY;
445                 break;
446         case DID_BAD_TARGET:
447         case DID_ABORT:
448         case DID_PARITY:
449         case DID_RESET:
450         case DID_BAD_INTR:
451                 old_hdr->result = EIO;
452                 break;
453         case DID_ERROR:
454                 old_hdr->result = (srp->sense_b[0] == 0 && 
455                                   hp->masked_status == GOOD) ? 0 : EIO;
456                 break;
457         default:
458                 old_hdr->result = EIO;
459                 break;
460         }
461
462         /* Now copy the result back to the user buffer.  */
463         if (count >= SZ_SG_HEADER) {
464                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
465                         retval = -EFAULT;
466                         goto free_old_hdr;
467                 }
468                 buf += SZ_SG_HEADER;
469                 if (count > old_hdr->reply_len)
470                         count = old_hdr->reply_len;
471                 if (count > SZ_SG_HEADER) {
472                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
473                                 retval = -EFAULT;
474                                 goto free_old_hdr;
475                         }
476                 }
477         } else
478                 count = (old_hdr->result == 0) ? 0 : -EIO;
479         sg_finish_rem_req(srp);
480         retval = count;
481 free_old_hdr:
482         kfree(old_hdr);
483         return retval;
484 }
485
486 static ssize_t
487 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
488 {
489         sg_io_hdr_t *hp = &srp->header;
490         int err = 0;
491         int len;
492
493         if (count < SZ_SG_IO_HDR) {
494                 err = -EINVAL;
495                 goto err_out;
496         }
497         hp->sb_len_wr = 0;
498         if ((hp->mx_sb_len > 0) && hp->sbp) {
499                 if ((CHECK_CONDITION & hp->masked_status) ||
500                     (DRIVER_SENSE & hp->driver_status)) {
501                         int sb_len = SCSI_SENSE_BUFFERSIZE;
502                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
503                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
504                         len = (len > sb_len) ? sb_len : len;
505                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
506                                 err = -EFAULT;
507                                 goto err_out;
508                         }
509                         hp->sb_len_wr = len;
510                 }
511         }
512         if (hp->masked_status || hp->host_status || hp->driver_status)
513                 hp->info |= SG_INFO_CHECK;
514         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
515                 err = -EFAULT;
516                 goto err_out;
517         }
518 err_out:
519         err = sg_finish_rem_req(srp);
520         return (0 == err) ? count : err;
521 }
522
523 static ssize_t
524 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
525 {
526         int mxsize, cmd_size, k;
527         int input_size, blocking;
528         unsigned char opcode;
529         Sg_device *sdp;
530         Sg_fd *sfp;
531         Sg_request *srp;
532         struct sg_header old_hdr;
533         sg_io_hdr_t *hp;
534         unsigned char cmnd[MAX_COMMAND_SIZE];
535
536         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
537                 return -ENXIO;
538         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
539                                    sdp->disk->disk_name, (int) count));
540         if (sdp->detached)
541                 return -ENODEV;
542         if (!((filp->f_flags & O_NONBLOCK) ||
543               scsi_block_when_processing_errors(sdp->device)))
544                 return -ENXIO;
545
546         if (!access_ok(VERIFY_READ, buf, count))
547                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
548         if (count < SZ_SG_HEADER)
549                 return -EIO;
550         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
551                 return -EFAULT;
552         blocking = !(filp->f_flags & O_NONBLOCK);
553         if (old_hdr.reply_len < 0)
554                 return sg_new_write(sfp, filp, buf, count,
555                                     blocking, 0, 0, NULL);
556         if (count < (SZ_SG_HEADER + 6))
557                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
558
559         if (!(srp = sg_add_request(sfp))) {
560                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
561                 return -EDOM;
562         }
563         buf += SZ_SG_HEADER;
564         __get_user(opcode, buf);
565         if (sfp->next_cmd_len > 0) {
566                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
567                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
568                         sfp->next_cmd_len = 0;
569                         sg_remove_request(sfp, srp);
570                         return -EIO;
571                 }
572                 cmd_size = sfp->next_cmd_len;
573                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
574         } else {
575                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
576                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
577                         cmd_size = 12;
578         }
579         SCSI_LOG_TIMEOUT(4, printk(
580                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
581 /* Determine buffer size.  */
582         input_size = count - cmd_size;
583         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
584         mxsize -= SZ_SG_HEADER;
585         input_size -= SZ_SG_HEADER;
586         if (input_size < 0) {
587                 sg_remove_request(sfp, srp);
588                 return -EIO;    /* User did not pass enough bytes for this command. */
589         }
590         hp = &srp->header;
591         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
592         hp->cmd_len = (unsigned char) cmd_size;
593         hp->iovec_count = 0;
594         hp->mx_sb_len = 0;
595         if (input_size > 0)
596                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
597                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
598         else
599                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
600         hp->dxfer_len = mxsize;
601         if (hp->dxfer_direction == SG_DXFER_TO_DEV)
602                 hp->dxferp = (char __user *)buf + cmd_size;
603         else
604                 hp->dxferp = NULL;
605         hp->sbp = NULL;
606         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
607         hp->flags = input_size; /* structure abuse ... */
608         hp->pack_id = old_hdr.pack_id;
609         hp->usr_ptr = NULL;
610         if (__copy_from_user(cmnd, buf, cmd_size))
611                 return -EFAULT;
612         /*
613          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
614          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
615          * is a non-zero input_size, so emit a warning.
616          */
617         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
618                 static char cmd[TASK_COMM_LEN];
619                 if (strcmp(current->comm, cmd) && printk_ratelimit()) {
620                         printk(KERN_WARNING
621                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
622                                "guessing data in;\n" KERN_WARNING "   "
623                                "program %s not setting count and/or reply_len properly\n",
624                                old_hdr.reply_len - (int)SZ_SG_HEADER,
625                                input_size, (unsigned int) cmnd[0],
626                                current->comm);
627                         strcpy(cmd, current->comm);
628                 }
629         }
630         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
631         return (k < 0) ? k : count;
632 }
633
634 static ssize_t
635 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
636                  size_t count, int blocking, int read_only, int sg_io_owned,
637                  Sg_request **o_srp)
638 {
639         int k;
640         Sg_request *srp;
641         sg_io_hdr_t *hp;
642         unsigned char cmnd[MAX_COMMAND_SIZE];
643         int timeout;
644         unsigned long ul_timeout;
645
646         if (count < SZ_SG_IO_HDR)
647                 return -EINVAL;
648         if (!access_ok(VERIFY_READ, buf, count))
649                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
650
651         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
652         if (!(srp = sg_add_request(sfp))) {
653                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
654                 return -EDOM;
655         }
656         srp->sg_io_owned = sg_io_owned;
657         hp = &srp->header;
658         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
659                 sg_remove_request(sfp, srp);
660                 return -EFAULT;
661         }
662         if (hp->interface_id != 'S') {
663                 sg_remove_request(sfp, srp);
664                 return -ENOSYS;
665         }
666         if (hp->flags & SG_FLAG_MMAP_IO) {
667                 if (hp->dxfer_len > sfp->reserve.bufflen) {
668                         sg_remove_request(sfp, srp);
669                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
670                 }
671                 if (hp->flags & SG_FLAG_DIRECT_IO) {
672                         sg_remove_request(sfp, srp);
673                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
674                 }
675                 if (sg_res_in_use(sfp)) {
676                         sg_remove_request(sfp, srp);
677                         return -EBUSY;  /* reserve buffer already being used */
678                 }
679         }
680         ul_timeout = msecs_to_jiffies(srp->header.timeout);
681         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
682         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
683                 sg_remove_request(sfp, srp);
684                 return -EMSGSIZE;
685         }
686         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
687                 sg_remove_request(sfp, srp);
688                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
689         }
690         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
691                 sg_remove_request(sfp, srp);
692                 return -EFAULT;
693         }
694         if (read_only && sg_allow_access(file, cmnd)) {
695                 sg_remove_request(sfp, srp);
696                 return -EPERM;
697         }
698         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
699         if (k < 0)
700                 return k;
701         if (o_srp)
702                 *o_srp = srp;
703         return count;
704 }
705
706 static int
707 sg_common_write(Sg_fd * sfp, Sg_request * srp,
708                 unsigned char *cmnd, int timeout, int blocking)
709 {
710         int k, data_dir;
711         Sg_device *sdp = sfp->parentdp;
712         sg_io_hdr_t *hp = &srp->header;
713
714         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
715         hp->status = 0;
716         hp->masked_status = 0;
717         hp->msg_status = 0;
718         hp->info = 0;
719         hp->host_status = 0;
720         hp->driver_status = 0;
721         hp->resid = 0;
722         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
723                           (int) cmnd[0], (int) hp->cmd_len));
724
725         k = sg_start_req(srp, cmnd);
726         if (k) {
727                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
728                 sg_finish_rem_req(srp);
729                 return k;       /* probably out of space --> ENOMEM */
730         }
731         if (sdp->detached) {
732                 sg_finish_rem_req(srp);
733                 return -ENODEV;
734         }
735
736         switch (hp->dxfer_direction) {
737         case SG_DXFER_TO_FROM_DEV:
738         case SG_DXFER_FROM_DEV:
739                 data_dir = DMA_FROM_DEVICE;
740                 break;
741         case SG_DXFER_TO_DEV:
742                 data_dir = DMA_TO_DEVICE;
743                 break;
744         case SG_DXFER_UNKNOWN:
745                 data_dir = DMA_BIDIRECTIONAL;
746                 break;
747         default:
748                 data_dir = DMA_NONE;
749                 break;
750         }
751         hp->duration = jiffies_to_msecs(jiffies);
752
753         srp->rq->timeout = timeout;
754         kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
755         blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
756                               srp->rq, 1, sg_rq_end_io);
757         return 0;
758 }
759
760 static int
761 sg_ioctl(struct inode *inode, struct file *filp,
762          unsigned int cmd_in, unsigned long arg)
763 {
764         void __user *p = (void __user *)arg;
765         int __user *ip = p;
766         int result, val, read_only;
767         Sg_device *sdp;
768         Sg_fd *sfp;
769         Sg_request *srp;
770         unsigned long iflags;
771
772         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
773                 return -ENXIO;
774
775         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
776                                    sdp->disk->disk_name, (int) cmd_in));
777         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
778
779         switch (cmd_in) {
780         case SG_IO:
781                 {
782                         int blocking = 1;       /* ignore O_NONBLOCK flag */
783
784                         if (sdp->detached)
785                                 return -ENODEV;
786                         if (!scsi_block_when_processing_errors(sdp->device))
787                                 return -ENXIO;
788                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
789                                 return -EFAULT;
790                         result =
791                             sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
792                                          blocking, read_only, 1, &srp);
793                         if (result < 0)
794                                 return result;
795                         while (1) {
796                                 result = 0;     /* following macro to beat race condition */
797                                 __wait_event_interruptible(sfp->read_wait,
798                                         (srp->done || sdp->detached),
799                                         result);
800                                 if (sdp->detached)
801                                         return -ENODEV;
802                                 write_lock_irq(&sfp->rq_list_lock);
803                                 if (srp->done) {
804                                         srp->done = 2;
805                                         write_unlock_irq(&sfp->rq_list_lock);
806                                         break;
807                                 }
808                                 srp->orphan = 1;
809                                 write_unlock_irq(&sfp->rq_list_lock);
810                                 return result;  /* -ERESTARTSYS because signal hit process */
811                         }
812                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
813                         return (result < 0) ? result : 0;
814                 }
815         case SG_SET_TIMEOUT:
816                 result = get_user(val, ip);
817                 if (result)
818                         return result;
819                 if (val < 0)
820                         return -EIO;
821                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
822                     val = MULDIV (INT_MAX, USER_HZ, HZ);
823                 sfp->timeout_user = val;
824                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
825
826                 return 0;
827         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
828                                 /* strange ..., for backward compatibility */
829                 return sfp->timeout_user;
830         case SG_SET_FORCE_LOW_DMA:
831                 result = get_user(val, ip);
832                 if (result)
833                         return result;
834                 if (val) {
835                         sfp->low_dma = 1;
836                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
837                                 val = (int) sfp->reserve.bufflen;
838                                 sg_remove_scat(&sfp->reserve);
839                                 sg_build_reserve(sfp, val);
840                         }
841                 } else {
842                         if (sdp->detached)
843                                 return -ENODEV;
844                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
845                 }
846                 return 0;
847         case SG_GET_LOW_DMA:
848                 return put_user((int) sfp->low_dma, ip);
849         case SG_GET_SCSI_ID:
850                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
851                         return -EFAULT;
852                 else {
853                         sg_scsi_id_t __user *sg_idp = p;
854
855                         if (sdp->detached)
856                                 return -ENODEV;
857                         __put_user((int) sdp->device->host->host_no,
858                                    &sg_idp->host_no);
859                         __put_user((int) sdp->device->channel,
860                                    &sg_idp->channel);
861                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
862                         __put_user((int) sdp->device->lun, &sg_idp->lun);
863                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
864                         __put_user((short) sdp->device->host->cmd_per_lun,
865                                    &sg_idp->h_cmd_per_lun);
866                         __put_user((short) sdp->device->queue_depth,
867                                    &sg_idp->d_queue_depth);
868                         __put_user(0, &sg_idp->unused[0]);
869                         __put_user(0, &sg_idp->unused[1]);
870                         return 0;
871                 }
872         case SG_SET_FORCE_PACK_ID:
873                 result = get_user(val, ip);
874                 if (result)
875                         return result;
876                 sfp->force_packid = val ? 1 : 0;
877                 return 0;
878         case SG_GET_PACK_ID:
879                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
880                         return -EFAULT;
881                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
882                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
883                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
884                                 read_unlock_irqrestore(&sfp->rq_list_lock,
885                                                        iflags);
886                                 __put_user(srp->header.pack_id, ip);
887                                 return 0;
888                         }
889                 }
890                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
891                 __put_user(-1, ip);
892                 return 0;
893         case SG_GET_NUM_WAITING:
894                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
895                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
896                         if ((1 == srp->done) && (!srp->sg_io_owned))
897                                 ++val;
898                 }
899                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
900                 return put_user(val, ip);
901         case SG_GET_SG_TABLESIZE:
902                 return put_user(sdp->sg_tablesize, ip);
903         case SG_SET_RESERVED_SIZE:
904                 result = get_user(val, ip);
905                 if (result)
906                         return result;
907                 if (val < 0)
908                         return -EINVAL;
909                 val = min_t(int, val,
910                             queue_max_sectors(sdp->device->request_queue) * 512);
911                 if (val != sfp->reserve.bufflen) {
912                         if (sg_res_in_use(sfp) || sfp->mmap_called)
913                                 return -EBUSY;
914                         sg_remove_scat(&sfp->reserve);
915                         sg_build_reserve(sfp, val);
916                 }
917                 return 0;
918         case SG_GET_RESERVED_SIZE:
919                 val = min_t(int, sfp->reserve.bufflen,
920                             queue_max_sectors(sdp->device->request_queue) * 512);
921                 return put_user(val, ip);
922         case SG_SET_COMMAND_Q:
923                 result = get_user(val, ip);
924                 if (result)
925                         return result;
926                 sfp->cmd_q = val ? 1 : 0;
927                 return 0;
928         case SG_GET_COMMAND_Q:
929                 return put_user((int) sfp->cmd_q, ip);
930         case SG_SET_KEEP_ORPHAN:
931                 result = get_user(val, ip);
932                 if (result)
933                         return result;
934                 sfp->keep_orphan = val;
935                 return 0;
936         case SG_GET_KEEP_ORPHAN:
937                 return put_user((int) sfp->keep_orphan, ip);
938         case SG_NEXT_CMD_LEN:
939                 result = get_user(val, ip);
940                 if (result)
941                         return result;
942                 sfp->next_cmd_len = (val > 0) ? val : 0;
943                 return 0;
944         case SG_GET_VERSION_NUM:
945                 return put_user(sg_version_num, ip);
946         case SG_GET_ACCESS_COUNT:
947                 /* faked - we don't have a real access count anymore */
948                 val = (sdp->device ? 1 : 0);
949                 return put_user(val, ip);
950         case SG_GET_REQUEST_TABLE:
951                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
952                         return -EFAULT;
953                 else {
954                         sg_req_info_t *rinfo;
955                         unsigned int ms;
956
957                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
958                                                                 GFP_KERNEL);
959                         if (!rinfo)
960                                 return -ENOMEM;
961                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
962                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
963                              ++val, srp = srp ? srp->nextrp : srp) {
964                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
965                                 if (srp) {
966                                         rinfo[val].req_state = srp->done + 1;
967                                         rinfo[val].problem =
968                                             srp->header.masked_status & 
969                                             srp->header.host_status & 
970                                             srp->header.driver_status;
971                                         if (srp->done)
972                                                 rinfo[val].duration =
973                                                         srp->header.duration;
974                                         else {
975                                                 ms = jiffies_to_msecs(jiffies);
976                                                 rinfo[val].duration =
977                                                     (ms > srp->header.duration) ?
978                                                     (ms - srp->header.duration) : 0;
979                                         }
980                                         rinfo[val].orphan = srp->orphan;
981                                         rinfo[val].sg_io_owned =
982                                                         srp->sg_io_owned;
983                                         rinfo[val].pack_id =
984                                                         srp->header.pack_id;
985                                         rinfo[val].usr_ptr =
986                                                         srp->header.usr_ptr;
987                                 }
988                         }
989                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
990                         result = __copy_to_user(p, rinfo, 
991                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
992                         result = result ? -EFAULT : 0;
993                         kfree(rinfo);
994                         return result;
995                 }
996         case SG_EMULATED_HOST:
997                 if (sdp->detached)
998                         return -ENODEV;
999                 return put_user(sdp->device->host->hostt->emulated, ip);
1000         case SG_SCSI_RESET:
1001                 if (sdp->detached)
1002                         return -ENODEV;
1003                 if (filp->f_flags & O_NONBLOCK) {
1004                         if (scsi_host_in_recovery(sdp->device->host))
1005                                 return -EBUSY;
1006                 } else if (!scsi_block_when_processing_errors(sdp->device))
1007                         return -EBUSY;
1008                 result = get_user(val, ip);
1009                 if (result)
1010                         return result;
1011                 if (SG_SCSI_RESET_NOTHING == val)
1012                         return 0;
1013                 switch (val) {
1014                 case SG_SCSI_RESET_DEVICE:
1015                         val = SCSI_TRY_RESET_DEVICE;
1016                         break;
1017                 case SG_SCSI_RESET_TARGET:
1018                         val = SCSI_TRY_RESET_TARGET;
1019                         break;
1020                 case SG_SCSI_RESET_BUS:
1021                         val = SCSI_TRY_RESET_BUS;
1022                         break;
1023                 case SG_SCSI_RESET_HOST:
1024                         val = SCSI_TRY_RESET_HOST;
1025                         break;
1026                 default:
1027                         return -EINVAL;
1028                 }
1029                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1030                         return -EACCES;
1031                 return (scsi_reset_provider(sdp->device, val) ==
1032                         SUCCESS) ? 0 : -EIO;
1033         case SCSI_IOCTL_SEND_COMMAND:
1034                 if (sdp->detached)
1035                         return -ENODEV;
1036                 if (read_only) {
1037                         unsigned char opcode = WRITE_6;
1038                         Scsi_Ioctl_Command __user *siocp = p;
1039
1040                         if (copy_from_user(&opcode, siocp->data, 1))
1041                                 return -EFAULT;
1042                         if (sg_allow_access(filp, &opcode))
1043                                 return -EPERM;
1044                 }
1045                 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1046         case SG_SET_DEBUG:
1047                 result = get_user(val, ip);
1048                 if (result)
1049                         return result;
1050                 sdp->sgdebug = (char) val;
1051                 return 0;
1052         case SCSI_IOCTL_GET_IDLUN:
1053         case SCSI_IOCTL_GET_BUS_NUMBER:
1054         case SCSI_IOCTL_PROBE_HOST:
1055         case SG_GET_TRANSFORM:
1056                 if (sdp->detached)
1057                         return -ENODEV;
1058                 return scsi_ioctl(sdp->device, cmd_in, p);
1059         case BLKSECTGET:
1060                 return put_user(queue_max_sectors(sdp->device->request_queue) * 512,
1061                                 ip);
1062         case BLKTRACESETUP:
1063                 return blk_trace_setup(sdp->device->request_queue,
1064                                        sdp->disk->disk_name,
1065                                        MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1066                                        NULL,
1067                                        (char *)arg);
1068         case BLKTRACESTART:
1069                 return blk_trace_startstop(sdp->device->request_queue, 1);
1070         case BLKTRACESTOP:
1071                 return blk_trace_startstop(sdp->device->request_queue, 0);
1072         case BLKTRACETEARDOWN:
1073                 return blk_trace_remove(sdp->device->request_queue);
1074         default:
1075                 if (read_only)
1076                         return -EPERM;  /* don't know so take safe approach */
1077                 return scsi_ioctl(sdp->device, cmd_in, p);
1078         }
1079 }
1080
1081 #ifdef CONFIG_COMPAT
1082 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1083 {
1084         Sg_device *sdp;
1085         Sg_fd *sfp;
1086         struct scsi_device *sdev;
1087
1088         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1089                 return -ENXIO;
1090
1091         sdev = sdp->device;
1092         if (sdev->host->hostt->compat_ioctl) { 
1093                 int ret;
1094
1095                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1096
1097                 return ret;
1098         }
1099         
1100         return -ENOIOCTLCMD;
1101 }
1102 #endif
1103
1104 static unsigned int
1105 sg_poll(struct file *filp, poll_table * wait)
1106 {
1107         unsigned int res = 0;
1108         Sg_device *sdp;
1109         Sg_fd *sfp;
1110         Sg_request *srp;
1111         int count = 0;
1112         unsigned long iflags;
1113
1114         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1115             || sfp->closed)
1116                 return POLLERR;
1117         poll_wait(filp, &sfp->read_wait, wait);
1118         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1119         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1120                 /* if any read waiting, flag it */
1121                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1122                         res = POLLIN | POLLRDNORM;
1123                 ++count;
1124         }
1125         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1126
1127         if (sdp->detached)
1128                 res |= POLLHUP;
1129         else if (!sfp->cmd_q) {
1130                 if (0 == count)
1131                         res |= POLLOUT | POLLWRNORM;
1132         } else if (count < SG_MAX_QUEUE)
1133                 res |= POLLOUT | POLLWRNORM;
1134         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1135                                    sdp->disk->disk_name, (int) res));
1136         return res;
1137 }
1138
1139 static int
1140 sg_fasync(int fd, struct file *filp, int mode)
1141 {
1142         Sg_device *sdp;
1143         Sg_fd *sfp;
1144
1145         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1146                 return -ENXIO;
1147         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1148                                    sdp->disk->disk_name, mode));
1149
1150         return fasync_helper(fd, filp, mode, &sfp->async_qp);
1151 }
1152
1153 static int
1154 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1155 {
1156         Sg_fd *sfp;
1157         unsigned long offset, len, sa;
1158         Sg_scatter_hold *rsv_schp;
1159         int k, length;
1160
1161         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1162                 return VM_FAULT_SIGBUS;
1163         rsv_schp = &sfp->reserve;
1164         offset = vmf->pgoff << PAGE_SHIFT;
1165         if (offset >= rsv_schp->bufflen)
1166                 return VM_FAULT_SIGBUS;
1167         SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1168                                    offset, rsv_schp->k_use_sg));
1169         sa = vma->vm_start;
1170         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1171         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1172                 len = vma->vm_end - sa;
1173                 len = (len < length) ? len : length;
1174                 if (offset < len) {
1175                         struct page *page = nth_page(rsv_schp->pages[k],
1176                                                      offset >> PAGE_SHIFT);
1177                         get_page(page); /* increment page count */
1178                         vmf->page = page;
1179                         return 0; /* success */
1180                 }
1181                 sa += len;
1182                 offset -= len;
1183         }
1184
1185         return VM_FAULT_SIGBUS;
1186 }
1187
1188 static struct vm_operations_struct sg_mmap_vm_ops = {
1189         .fault = sg_vma_fault,
1190 };
1191
1192 static int
1193 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1194 {
1195         Sg_fd *sfp;
1196         unsigned long req_sz, len, sa;
1197         Sg_scatter_hold *rsv_schp;
1198         int k, length;
1199
1200         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1201                 return -ENXIO;
1202         req_sz = vma->vm_end - vma->vm_start;
1203         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1204                                    (void *) vma->vm_start, (int) req_sz));
1205         if (vma->vm_pgoff)
1206                 return -EINVAL; /* want no offset */
1207         rsv_schp = &sfp->reserve;
1208         if (req_sz > rsv_schp->bufflen)
1209                 return -ENOMEM; /* cannot map more than reserved buffer */
1210
1211         sa = vma->vm_start;
1212         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1213         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1214                 len = vma->vm_end - sa;
1215                 len = (len < length) ? len : length;
1216                 sa += len;
1217         }
1218
1219         sfp->mmap_called = 1;
1220         vma->vm_flags |= VM_RESERVED;
1221         vma->vm_private_data = sfp;
1222         vma->vm_ops = &sg_mmap_vm_ops;
1223         return 0;
1224 }
1225
1226 static void sg_rq_end_io_usercontext(struct work_struct *work)
1227 {
1228         struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1229         struct sg_fd *sfp = srp->parentfp;
1230
1231         sg_finish_rem_req(srp);
1232         kref_put(&sfp->f_ref, sg_remove_sfp);
1233 }
1234
1235 /*
1236  * This function is a "bottom half" handler that is called by the mid
1237  * level when a command is completed (or has failed).
1238  */
1239 static void sg_rq_end_io(struct request *rq, int uptodate)
1240 {
1241         struct sg_request *srp = rq->end_io_data;
1242         Sg_device *sdp;
1243         Sg_fd *sfp;
1244         unsigned long iflags;
1245         unsigned int ms;
1246         char *sense;
1247         int result, resid, done = 1;
1248
1249         if (WARN_ON(srp->done != 0))
1250                 return;
1251
1252         sfp = srp->parentfp;
1253         if (WARN_ON(sfp == NULL))
1254                 return;
1255
1256         sdp = sfp->parentdp;
1257         if (unlikely(sdp->detached))
1258                 printk(KERN_INFO "sg_rq_end_io: device detached\n");
1259
1260         sense = rq->sense;
1261         result = rq->errors;
1262         resid = rq->resid_len;
1263
1264         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1265                 sdp->disk->disk_name, srp->header.pack_id, result));
1266         srp->header.resid = resid;
1267         ms = jiffies_to_msecs(jiffies);
1268         srp->header.duration = (ms > srp->header.duration) ?
1269                                 (ms - srp->header.duration) : 0;
1270         if (0 != result) {
1271                 struct scsi_sense_hdr sshdr;
1272
1273                 srp->header.status = 0xff & result;
1274                 srp->header.masked_status = status_byte(result);
1275                 srp->header.msg_status = msg_byte(result);
1276                 srp->header.host_status = host_byte(result);
1277                 srp->header.driver_status = driver_byte(result);
1278                 if ((sdp->sgdebug > 0) &&
1279                     ((CHECK_CONDITION == srp->header.masked_status) ||
1280                      (COMMAND_TERMINATED == srp->header.masked_status)))
1281                         __scsi_print_sense("sg_cmd_done", sense,
1282                                            SCSI_SENSE_BUFFERSIZE);
1283
1284                 /* Following if statement is a patch supplied by Eric Youngdale */
1285                 if (driver_byte(result) != 0
1286                     && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1287                     && !scsi_sense_is_deferred(&sshdr)
1288                     && sshdr.sense_key == UNIT_ATTENTION
1289                     && sdp->device->removable) {
1290                         /* Detected possible disc change. Set the bit - this */
1291                         /* may be used if there are filesystems using this device */
1292                         sdp->device->changed = 1;
1293                 }
1294         }
1295         /* Rely on write phase to clean out srp status values, so no "else" */
1296
1297         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1298         if (unlikely(srp->orphan)) {
1299                 if (sfp->keep_orphan)
1300                         srp->sg_io_owned = 0;
1301                 else
1302                         done = 0;
1303         }
1304         srp->done = done;
1305         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1306
1307         if (likely(done)) {
1308                 /* Now wake up any sg_read() that is waiting for this
1309                  * packet.
1310                  */
1311                 wake_up_interruptible(&sfp->read_wait);
1312                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1313                 kref_put(&sfp->f_ref, sg_remove_sfp);
1314         } else {
1315                 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1316                 schedule_work(&srp->ew.work);
1317         }
1318 }
1319
1320 static struct file_operations sg_fops = {
1321         .owner = THIS_MODULE,
1322         .read = sg_read,
1323         .write = sg_write,
1324         .poll = sg_poll,
1325         .ioctl = sg_ioctl,
1326 #ifdef CONFIG_COMPAT
1327         .compat_ioctl = sg_compat_ioctl,
1328 #endif
1329         .open = sg_open,
1330         .mmap = sg_mmap,
1331         .release = sg_release,
1332         .fasync = sg_fasync,
1333 };
1334
1335 static struct class *sg_sysfs_class;
1336
1337 static int sg_sysfs_valid = 0;
1338
1339 static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1340 {
1341         struct request_queue *q = scsidp->request_queue;
1342         Sg_device *sdp;
1343         unsigned long iflags;
1344         int error;
1345         u32 k;
1346
1347         sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1348         if (!sdp) {
1349                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1350                 return ERR_PTR(-ENOMEM);
1351         }
1352
1353         if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1354                 printk(KERN_WARNING "idr expansion Sg_device failure\n");
1355                 error = -ENOMEM;
1356                 goto out;
1357         }
1358
1359         write_lock_irqsave(&sg_index_lock, iflags);
1360
1361         error = idr_get_new(&sg_index_idr, sdp, &k);
1362         if (error) {
1363                 write_unlock_irqrestore(&sg_index_lock, iflags);
1364                 printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1365                        error);
1366                 goto out;
1367         }
1368
1369         if (unlikely(k >= SG_MAX_DEVS))
1370                 goto overflow;
1371
1372         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1373         sprintf(disk->disk_name, "sg%d", k);
1374         disk->first_minor = k;
1375         sdp->disk = disk;
1376         sdp->device = scsidp;
1377         INIT_LIST_HEAD(&sdp->sfds);
1378         init_waitqueue_head(&sdp->o_excl_wait);
1379         sdp->sg_tablesize = min(queue_max_hw_segments(q),
1380                                 queue_max_phys_segments(q));
1381         sdp->index = k;
1382         kref_init(&sdp->d_ref);
1383
1384         write_unlock_irqrestore(&sg_index_lock, iflags);
1385
1386         error = 0;
1387  out:
1388         if (error) {
1389                 kfree(sdp);
1390                 return ERR_PTR(error);
1391         }
1392         return sdp;
1393
1394  overflow:
1395         idr_remove(&sg_index_idr, k);
1396         write_unlock_irqrestore(&sg_index_lock, iflags);
1397         sdev_printk(KERN_WARNING, scsidp,
1398                     "Unable to attach sg device type=%d, minor "
1399                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1400         error = -ENODEV;
1401         goto out;
1402 }
1403
1404 static int
1405 sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1406 {
1407         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1408         struct gendisk *disk;
1409         Sg_device *sdp = NULL;
1410         struct cdev * cdev = NULL;
1411         int error;
1412         unsigned long iflags;
1413
1414         disk = alloc_disk(1);
1415         if (!disk) {
1416                 printk(KERN_WARNING "alloc_disk failed\n");
1417                 return -ENOMEM;
1418         }
1419         disk->major = SCSI_GENERIC_MAJOR;
1420
1421         error = -ENOMEM;
1422         cdev = cdev_alloc();
1423         if (!cdev) {
1424                 printk(KERN_WARNING "cdev_alloc failed\n");
1425                 goto out;
1426         }
1427         cdev->owner = THIS_MODULE;
1428         cdev->ops = &sg_fops;
1429
1430         sdp = sg_alloc(disk, scsidp);
1431         if (IS_ERR(sdp)) {
1432                 printk(KERN_WARNING "sg_alloc failed\n");
1433                 error = PTR_ERR(sdp);
1434                 goto out;
1435         }
1436
1437         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1438         if (error)
1439                 goto cdev_add_err;
1440
1441         sdp->cdev = cdev;
1442         if (sg_sysfs_valid) {
1443                 struct device *sg_class_member;
1444
1445                 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1446                                                 MKDEV(SCSI_GENERIC_MAJOR,
1447                                                       sdp->index),
1448                                                 sdp, "%s", disk->disk_name);
1449                 if (IS_ERR(sg_class_member)) {
1450                         printk(KERN_ERR "sg_add: "
1451                                "device_create failed\n");
1452                         error = PTR_ERR(sg_class_member);
1453                         goto cdev_add_err;
1454                 }
1455                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1456                                           &sg_class_member->kobj, "generic");
1457                 if (error)
1458                         printk(KERN_ERR "sg_add: unable to make symlink "
1459                                         "'generic' back to sg%d\n", sdp->index);
1460         } else
1461                 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1462
1463         sdev_printk(KERN_NOTICE, scsidp,
1464                     "Attached scsi generic sg%d type %d\n", sdp->index,
1465                     scsidp->type);
1466
1467         dev_set_drvdata(cl_dev, sdp);
1468
1469         return 0;
1470
1471 cdev_add_err:
1472         write_lock_irqsave(&sg_index_lock, iflags);
1473         idr_remove(&sg_index_idr, sdp->index);
1474         write_unlock_irqrestore(&sg_index_lock, iflags);
1475         kfree(sdp);
1476
1477 out:
1478         put_disk(disk);
1479         if (cdev)
1480                 cdev_del(cdev);
1481         return error;
1482 }
1483
1484 static void sg_device_destroy(struct kref *kref)
1485 {
1486         struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1487         unsigned long flags;
1488
1489         /* CAUTION!  Note that the device can still be found via idr_find()
1490          * even though the refcount is 0.  Therefore, do idr_remove() BEFORE
1491          * any other cleanup.
1492          */
1493
1494         write_lock_irqsave(&sg_index_lock, flags);
1495         idr_remove(&sg_index_idr, sdp->index);
1496         write_unlock_irqrestore(&sg_index_lock, flags);
1497
1498         SCSI_LOG_TIMEOUT(3,
1499                 printk("sg_device_destroy: %s\n",
1500                         sdp->disk->disk_name));
1501
1502         put_disk(sdp->disk);
1503         kfree(sdp);
1504 }
1505
1506 static void sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1507 {
1508         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1509         Sg_device *sdp = dev_get_drvdata(cl_dev);
1510         unsigned long iflags;
1511         Sg_fd *sfp;
1512
1513         if (!sdp || sdp->detached)
1514                 return;
1515
1516         SCSI_LOG_TIMEOUT(3, printk("sg_remove: %s\n", sdp->disk->disk_name));
1517
1518         /* Need a write lock to set sdp->detached. */
1519         write_lock_irqsave(&sg_index_lock, iflags);
1520         sdp->detached = 1;
1521         list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1522                 wake_up_interruptible(&sfp->read_wait);
1523                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1524         }
1525         write_unlock_irqrestore(&sg_index_lock, iflags);
1526
1527         sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1528         device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1529         cdev_del(sdp->cdev);
1530         sdp->cdev = NULL;
1531
1532         sg_put_dev(sdp);
1533 }
1534
1535 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1536 module_param_named(def_reserved_size, def_reserved_size, int,
1537                    S_IRUGO | S_IWUSR);
1538 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1539
1540 MODULE_AUTHOR("Douglas Gilbert");
1541 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1542 MODULE_LICENSE("GPL");
1543 MODULE_VERSION(SG_VERSION_STR);
1544 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1545
1546 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1547                 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1548 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1549 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1550
1551 static int __init
1552 init_sg(void)
1553 {
1554         int rc;
1555
1556         if (scatter_elem_sz < PAGE_SIZE) {
1557                 scatter_elem_sz = PAGE_SIZE;
1558                 scatter_elem_sz_prev = scatter_elem_sz;
1559         }
1560         if (def_reserved_size >= 0)
1561                 sg_big_buff = def_reserved_size;
1562         else
1563                 def_reserved_size = sg_big_buff;
1564
1565         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 
1566                                     SG_MAX_DEVS, "sg");
1567         if (rc)
1568                 return rc;
1569         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1570         if ( IS_ERR(sg_sysfs_class) ) {
1571                 rc = PTR_ERR(sg_sysfs_class);
1572                 goto err_out;
1573         }
1574         sg_sysfs_valid = 1;
1575         rc = scsi_register_interface(&sg_interface);
1576         if (0 == rc) {
1577 #ifdef CONFIG_SCSI_PROC_FS
1578                 sg_proc_init();
1579 #endif                          /* CONFIG_SCSI_PROC_FS */
1580                 return 0;
1581         }
1582         class_destroy(sg_sysfs_class);
1583 err_out:
1584         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1585         return rc;
1586 }
1587
1588 static void __exit
1589 exit_sg(void)
1590 {
1591 #ifdef CONFIG_SCSI_PROC_FS
1592         sg_proc_cleanup();
1593 #endif                          /* CONFIG_SCSI_PROC_FS */
1594         scsi_unregister_interface(&sg_interface);
1595         class_destroy(sg_sysfs_class);
1596         sg_sysfs_valid = 0;
1597         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1598                                  SG_MAX_DEVS);
1599         idr_destroy(&sg_index_idr);
1600 }
1601
1602 static int sg_start_req(Sg_request *srp, unsigned char *cmd)
1603 {
1604         int res;
1605         struct request *rq;
1606         Sg_fd *sfp = srp->parentfp;
1607         sg_io_hdr_t *hp = &srp->header;
1608         int dxfer_len = (int) hp->dxfer_len;
1609         int dxfer_dir = hp->dxfer_direction;
1610         unsigned int iov_count = hp->iovec_count;
1611         Sg_scatter_hold *req_schp = &srp->data;
1612         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1613         struct request_queue *q = sfp->parentdp->device->request_queue;
1614         struct rq_map_data *md, map_data;
1615         int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1616
1617         SCSI_LOG_TIMEOUT(4, printk(KERN_INFO "sg_start_req: dxfer_len=%d\n",
1618                                    dxfer_len));
1619
1620         rq = blk_get_request(q, rw, GFP_ATOMIC);
1621         if (!rq)
1622                 return -ENOMEM;
1623
1624         memcpy(rq->cmd, cmd, hp->cmd_len);
1625
1626         rq->cmd_len = hp->cmd_len;
1627         rq->cmd_type = REQ_TYPE_BLOCK_PC;
1628
1629         srp->rq = rq;
1630         rq->end_io_data = srp;
1631         rq->sense = srp->sense_b;
1632         rq->retries = SG_DEFAULT_RETRIES;
1633
1634         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1635                 return 0;
1636
1637         if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1638             dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1639             !sfp->parentdp->device->host->unchecked_isa_dma &&
1640             blk_rq_aligned(q, hp->dxferp, dxfer_len))
1641                 md = NULL;
1642         else
1643                 md = &map_data;
1644
1645         if (md) {
1646                 if (!sg_res_in_use(sfp) && dxfer_len <= rsv_schp->bufflen)
1647                         sg_link_reserve(sfp, srp, dxfer_len);
1648                 else {
1649                         res = sg_build_indirect(req_schp, sfp, dxfer_len);
1650                         if (res)
1651                                 return res;
1652                 }
1653
1654                 md->pages = req_schp->pages;
1655                 md->page_order = req_schp->page_order;
1656                 md->nr_entries = req_schp->k_use_sg;
1657                 md->offset = 0;
1658                 md->null_mapped = hp->dxferp ? 0 : 1;
1659         }
1660
1661         if (iov_count) {
1662                 int len, size = sizeof(struct sg_iovec) * iov_count;
1663                 struct iovec *iov;
1664
1665                 iov = kmalloc(size, GFP_ATOMIC);
1666                 if (!iov)
1667                         return -ENOMEM;
1668
1669                 if (copy_from_user(iov, hp->dxferp, size)) {
1670                         kfree(iov);
1671                         return -EFAULT;
1672                 }
1673
1674                 len = iov_length(iov, iov_count);
1675                 if (hp->dxfer_len < len) {
1676                         iov_count = iov_shorten(iov, iov_count, hp->dxfer_len);
1677                         len = hp->dxfer_len;
1678                 }
1679
1680                 res = blk_rq_map_user_iov(q, rq, md, (struct sg_iovec *)iov,
1681                                           iov_count,
1682                                           len, GFP_ATOMIC);
1683                 kfree(iov);
1684         } else
1685                 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1686                                       hp->dxfer_len, GFP_ATOMIC);
1687
1688         if (!res) {
1689                 srp->bio = rq->bio;
1690
1691                 if (!md) {
1692                         req_schp->dio_in_use = 1;
1693                         hp->info |= SG_INFO_DIRECT_IO;
1694                 }
1695         }
1696         return res;
1697 }
1698
1699 static int sg_finish_rem_req(Sg_request * srp)
1700 {
1701         int ret = 0;
1702
1703         Sg_fd *sfp = srp->parentfp;
1704         Sg_scatter_hold *req_schp = &srp->data;
1705
1706         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1707         if (srp->res_used)
1708                 sg_unlink_reserve(sfp, srp);
1709         else
1710                 sg_remove_scat(req_schp);
1711
1712         if (srp->rq) {
1713                 if (srp->bio)
1714                         ret = blk_rq_unmap_user(srp->bio);
1715
1716                 blk_put_request(srp->rq);
1717         }
1718
1719         sg_remove_request(sfp, srp);
1720
1721         return ret;
1722 }
1723
1724 static int
1725 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1726 {
1727         int sg_bufflen = tablesize * sizeof(struct page *);
1728         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1729
1730         schp->pages = kzalloc(sg_bufflen, gfp_flags);
1731         if (!schp->pages)
1732                 return -ENOMEM;
1733         schp->sglist_len = sg_bufflen;
1734         return tablesize;       /* number of scat_gath elements allocated */
1735 }
1736
1737 static int
1738 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1739 {
1740         int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1741         int sg_tablesize = sfp->parentdp->sg_tablesize;
1742         int blk_size = buff_size, order;
1743         gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1744
1745         if (blk_size < 0)
1746                 return -EFAULT;
1747         if (0 == blk_size)
1748                 ++blk_size;     /* don't know why */
1749         /* round request up to next highest SG_SECTOR_SZ byte boundary */
1750         blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1751         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1752                                    buff_size, blk_size));
1753
1754         /* N.B. ret_sz carried into this block ... */
1755         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1756         if (mx_sc_elems < 0)
1757                 return mx_sc_elems;     /* most likely -ENOMEM */
1758
1759         num = scatter_elem_sz;
1760         if (unlikely(num != scatter_elem_sz_prev)) {
1761                 if (num < PAGE_SIZE) {
1762                         scatter_elem_sz = PAGE_SIZE;
1763                         scatter_elem_sz_prev = PAGE_SIZE;
1764                 } else
1765                         scatter_elem_sz_prev = num;
1766         }
1767
1768         if (sfp->low_dma)
1769                 gfp_mask |= GFP_DMA;
1770
1771         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1772                 gfp_mask |= __GFP_ZERO;
1773
1774         order = get_order(num);
1775 retry:
1776         ret_sz = 1 << (PAGE_SHIFT + order);
1777
1778         for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1779              k++, rem_sz -= ret_sz) {
1780
1781                 num = (rem_sz > scatter_elem_sz_prev) ?
1782                         scatter_elem_sz_prev : rem_sz;
1783
1784                 schp->pages[k] = alloc_pages(gfp_mask, order);
1785                 if (!schp->pages[k])
1786                         goto out;
1787
1788                 if (num == scatter_elem_sz_prev) {
1789                         if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1790                                 scatter_elem_sz = ret_sz;
1791                                 scatter_elem_sz_prev = ret_sz;
1792                         }
1793                 }
1794
1795                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1796                                  "ret_sz=%d\n", k, num, ret_sz));
1797         }               /* end of for loop */
1798
1799         schp->page_order = order;
1800         schp->k_use_sg = k;
1801         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1802                          "rem_sz=%d\n", k, rem_sz));
1803
1804         schp->bufflen = blk_size;
1805         if (rem_sz > 0) /* must have failed */
1806                 return -ENOMEM;
1807         return 0;
1808 out:
1809         for (i = 0; i < k; i++)
1810                 __free_pages(schp->pages[k], order);
1811
1812         if (--order >= 0)
1813                 goto retry;
1814
1815         return -ENOMEM;
1816 }
1817
1818 static void
1819 sg_remove_scat(Sg_scatter_hold * schp)
1820 {
1821         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1822         if (schp->pages && schp->sglist_len > 0) {
1823                 if (!schp->dio_in_use) {
1824                         int k;
1825
1826                         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1827                                 SCSI_LOG_TIMEOUT(5, printk(
1828                                     "sg_remove_scat: k=%d, pg=0x%p\n",
1829                                     k, schp->pages[k]));
1830                                 __free_pages(schp->pages[k], schp->page_order);
1831                         }
1832
1833                         kfree(schp->pages);
1834                 }
1835         }
1836         memset(schp, 0, sizeof (*schp));
1837 }
1838
1839 static int
1840 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1841 {
1842         Sg_scatter_hold *schp = &srp->data;
1843         int k, num;
1844
1845         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
1846                                    num_read_xfer));
1847         if ((!outp) || (num_read_xfer <= 0))
1848                 return 0;
1849
1850         num = 1 << (PAGE_SHIFT + schp->page_order);
1851         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1852                 if (num > num_read_xfer) {
1853                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1854                                            num_read_xfer))
1855                                 return -EFAULT;
1856                         break;
1857                 } else {
1858                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1859                                            num))
1860                                 return -EFAULT;
1861                         num_read_xfer -= num;
1862                         if (num_read_xfer <= 0)
1863                                 break;
1864                         outp += num;
1865                 }
1866         }
1867
1868         return 0;
1869 }
1870
1871 static void
1872 sg_build_reserve(Sg_fd * sfp, int req_size)
1873 {
1874         Sg_scatter_hold *schp = &sfp->reserve;
1875
1876         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
1877         do {
1878                 if (req_size < PAGE_SIZE)
1879                         req_size = PAGE_SIZE;
1880                 if (0 == sg_build_indirect(schp, sfp, req_size))
1881                         return;
1882                 else
1883                         sg_remove_scat(schp);
1884                 req_size >>= 1; /* divide by 2 */
1885         } while (req_size > (PAGE_SIZE / 2));
1886 }
1887
1888 static void
1889 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1890 {
1891         Sg_scatter_hold *req_schp = &srp->data;
1892         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1893         int k, num, rem;
1894
1895         srp->res_used = 1;
1896         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
1897         rem = size;
1898
1899         num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1900         for (k = 0; k < rsv_schp->k_use_sg; k++) {
1901                 if (rem <= num) {
1902                         req_schp->k_use_sg = k + 1;
1903                         req_schp->sglist_len = rsv_schp->sglist_len;
1904                         req_schp->pages = rsv_schp->pages;
1905
1906                         req_schp->bufflen = size;
1907                         req_schp->page_order = rsv_schp->page_order;
1908                         break;
1909                 } else
1910                         rem -= num;
1911         }
1912
1913         if (k >= rsv_schp->k_use_sg)
1914                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
1915 }
1916
1917 static void
1918 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
1919 {
1920         Sg_scatter_hold *req_schp = &srp->data;
1921
1922         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
1923                                    (int) req_schp->k_use_sg));
1924         req_schp->k_use_sg = 0;
1925         req_schp->bufflen = 0;
1926         req_schp->pages = NULL;
1927         req_schp->page_order = 0;
1928         req_schp->sglist_len = 0;
1929         sfp->save_scat_len = 0;
1930         srp->res_used = 0;
1931 }
1932
1933 static Sg_request *
1934 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
1935 {
1936         Sg_request *resp;
1937         unsigned long iflags;
1938
1939         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1940         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
1941                 /* look for requests that are ready + not SG_IO owned */
1942                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
1943                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
1944                         resp->done = 2; /* guard against other readers */
1945                         break;
1946                 }
1947         }
1948         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1949         return resp;
1950 }
1951
1952 /* always adds to end of list */
1953 static Sg_request *
1954 sg_add_request(Sg_fd * sfp)
1955 {
1956         int k;
1957         unsigned long iflags;
1958         Sg_request *resp;
1959         Sg_request *rp = sfp->req_arr;
1960
1961         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1962         resp = sfp->headrp;
1963         if (!resp) {
1964                 memset(rp, 0, sizeof (Sg_request));
1965                 rp->parentfp = sfp;
1966                 resp = rp;
1967                 sfp->headrp = resp;
1968         } else {
1969                 if (0 == sfp->cmd_q)
1970                         resp = NULL;    /* command queuing disallowed */
1971                 else {
1972                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
1973                                 if (!rp->parentfp)
1974                                         break;
1975                         }
1976                         if (k < SG_MAX_QUEUE) {
1977                                 memset(rp, 0, sizeof (Sg_request));
1978                                 rp->parentfp = sfp;
1979                                 while (resp->nextrp)
1980                                         resp = resp->nextrp;
1981                                 resp->nextrp = rp;
1982                                 resp = rp;
1983                         } else
1984                                 resp = NULL;
1985                 }
1986         }
1987         if (resp) {
1988                 resp->nextrp = NULL;
1989                 resp->header.duration = jiffies_to_msecs(jiffies);
1990         }
1991         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1992         return resp;
1993 }
1994
1995 /* Return of 1 for found; 0 for not found */
1996 static int
1997 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
1998 {
1999         Sg_request *prev_rp;
2000         Sg_request *rp;
2001         unsigned long iflags;
2002         int res = 0;
2003
2004         if ((!sfp) || (!srp) || (!sfp->headrp))
2005                 return res;
2006         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2007         prev_rp = sfp->headrp;
2008         if (srp == prev_rp) {
2009                 sfp->headrp = prev_rp->nextrp;
2010                 prev_rp->parentfp = NULL;
2011                 res = 1;
2012         } else {
2013                 while ((rp = prev_rp->nextrp)) {
2014                         if (srp == rp) {
2015                                 prev_rp->nextrp = rp->nextrp;
2016                                 rp->parentfp = NULL;
2017                                 res = 1;
2018                                 break;
2019                         }
2020                         prev_rp = rp;
2021                 }
2022         }
2023         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2024         return res;
2025 }
2026
2027 static Sg_fd *
2028 sg_add_sfp(Sg_device * sdp, int dev)
2029 {
2030         Sg_fd *sfp;
2031         unsigned long iflags;
2032         int bufflen;
2033
2034         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2035         if (!sfp)
2036                 return NULL;
2037
2038         init_waitqueue_head(&sfp->read_wait);
2039         rwlock_init(&sfp->rq_list_lock);
2040
2041         kref_init(&sfp->f_ref);
2042         sfp->timeout = SG_DEFAULT_TIMEOUT;
2043         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2044         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2045         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2046             sdp->device->host->unchecked_isa_dma : 1;
2047         sfp->cmd_q = SG_DEF_COMMAND_Q;
2048         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2049         sfp->parentdp = sdp;
2050         write_lock_irqsave(&sg_index_lock, iflags);
2051         list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2052         write_unlock_irqrestore(&sg_index_lock, iflags);
2053         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2054         if (unlikely(sg_big_buff != def_reserved_size))
2055                 sg_big_buff = def_reserved_size;
2056
2057         bufflen = min_t(int, sg_big_buff,
2058                         queue_max_sectors(sdp->device->request_queue) * 512);
2059         sg_build_reserve(sfp, bufflen);
2060         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2061                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2062
2063         kref_get(&sdp->d_ref);
2064         __module_get(THIS_MODULE);
2065         return sfp;
2066 }
2067
2068 static void sg_remove_sfp_usercontext(struct work_struct *work)
2069 {
2070         struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2071         struct sg_device *sdp = sfp->parentdp;
2072
2073         /* Cleanup any responses which were never read(). */
2074         while (sfp->headrp)
2075                 sg_finish_rem_req(sfp->headrp);
2076
2077         if (sfp->reserve.bufflen > 0) {
2078                 SCSI_LOG_TIMEOUT(6,
2079                         printk("sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2080                                 (int) sfp->reserve.bufflen,
2081                                 (int) sfp->reserve.k_use_sg));
2082                 sg_remove_scat(&sfp->reserve);
2083         }
2084
2085         SCSI_LOG_TIMEOUT(6,
2086                 printk("sg_remove_sfp: %s, sfp=0x%p\n",
2087                         sdp->disk->disk_name,
2088                         sfp));
2089         kfree(sfp);
2090
2091         scsi_device_put(sdp->device);
2092         sg_put_dev(sdp);
2093         module_put(THIS_MODULE);
2094 }
2095
2096 static void sg_remove_sfp(struct kref *kref)
2097 {
2098         struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2099         struct sg_device *sdp = sfp->parentdp;
2100         unsigned long iflags;
2101
2102         write_lock_irqsave(&sg_index_lock, iflags);
2103         list_del(&sfp->sfd_siblings);
2104         write_unlock_irqrestore(&sg_index_lock, iflags);
2105         wake_up_interruptible(&sdp->o_excl_wait);
2106
2107         INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2108         schedule_work(&sfp->ew.work);
2109 }
2110
2111 static int
2112 sg_res_in_use(Sg_fd * sfp)
2113 {
2114         const Sg_request *srp;
2115         unsigned long iflags;
2116
2117         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2118         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2119                 if (srp->res_used)
2120                         break;
2121         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2122         return srp ? 1 : 0;
2123 }
2124
2125 #ifdef CONFIG_SCSI_PROC_FS
2126 static int
2127 sg_idr_max_id(int id, void *p, void *data)
2128 {
2129         int *k = data;
2130
2131         if (*k < id)
2132                 *k = id;
2133
2134         return 0;
2135 }
2136
2137 static int
2138 sg_last_dev(void)
2139 {
2140         int k = -1;
2141         unsigned long iflags;
2142
2143         read_lock_irqsave(&sg_index_lock, iflags);
2144         idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2145         read_unlock_irqrestore(&sg_index_lock, iflags);
2146         return k + 1;           /* origin 1 */
2147 }
2148 #endif
2149
2150 /* must be called with sg_index_lock held */
2151 static Sg_device *sg_lookup_dev(int dev)
2152 {
2153         return idr_find(&sg_index_idr, dev);
2154 }
2155
2156 static Sg_device *sg_get_dev(int dev)
2157 {
2158         struct sg_device *sdp;
2159         unsigned long flags;
2160
2161         read_lock_irqsave(&sg_index_lock, flags);
2162         sdp = sg_lookup_dev(dev);
2163         if (!sdp)
2164                 sdp = ERR_PTR(-ENXIO);
2165         else if (sdp->detached) {
2166                 /* If sdp->detached, then the refcount may already be 0, in
2167                  * which case it would be a bug to do kref_get().
2168                  */
2169                 sdp = ERR_PTR(-ENODEV);
2170         } else
2171                 kref_get(&sdp->d_ref);
2172         read_unlock_irqrestore(&sg_index_lock, flags);
2173
2174         return sdp;
2175 }
2176
2177 static void sg_put_dev(struct sg_device *sdp)
2178 {
2179         kref_put(&sdp->d_ref, sg_device_destroy);
2180 }
2181
2182 #ifdef CONFIG_SCSI_PROC_FS
2183
2184 static struct proc_dir_entry *sg_proc_sgp = NULL;
2185
2186 static char sg_proc_sg_dirname[] = "scsi/sg";
2187
2188 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2189
2190 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2191 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2192                                   size_t count, loff_t *off);
2193 static struct file_operations adio_fops = {
2194         /* .owner, .read and .llseek added in sg_proc_init() */
2195         .open = sg_proc_single_open_adio,
2196         .write = sg_proc_write_adio,
2197         .release = single_release,
2198 };
2199
2200 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2201 static ssize_t sg_proc_write_dressz(struct file *filp, 
2202                 const char __user *buffer, size_t count, loff_t *off);
2203 static struct file_operations dressz_fops = {
2204         .open = sg_proc_single_open_dressz,
2205         .write = sg_proc_write_dressz,
2206         .release = single_release,
2207 };
2208
2209 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2210 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2211 static struct file_operations version_fops = {
2212         .open = sg_proc_single_open_version,
2213         .release = single_release,
2214 };
2215
2216 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2217 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2218 static struct file_operations devhdr_fops = {
2219         .open = sg_proc_single_open_devhdr,
2220         .release = single_release,
2221 };
2222
2223 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2224 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2225 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2226 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2227 static void dev_seq_stop(struct seq_file *s, void *v);
2228 static struct file_operations dev_fops = {
2229         .open = sg_proc_open_dev,
2230         .release = seq_release,
2231 };
2232 static struct seq_operations dev_seq_ops = {
2233         .start = dev_seq_start,
2234         .next  = dev_seq_next,
2235         .stop  = dev_seq_stop,
2236         .show  = sg_proc_seq_show_dev,
2237 };
2238
2239 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2240 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2241 static struct file_operations devstrs_fops = {
2242         .open = sg_proc_open_devstrs,
2243         .release = seq_release,
2244 };
2245 static struct seq_operations devstrs_seq_ops = {
2246         .start = dev_seq_start,
2247         .next  = dev_seq_next,
2248         .stop  = dev_seq_stop,
2249         .show  = sg_proc_seq_show_devstrs,
2250 };
2251
2252 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2253 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2254 static struct file_operations debug_fops = {
2255         .open = sg_proc_open_debug,
2256         .release = seq_release,
2257 };
2258 static struct seq_operations debug_seq_ops = {
2259         .start = dev_seq_start,
2260         .next  = dev_seq_next,
2261         .stop  = dev_seq_stop,
2262         .show  = sg_proc_seq_show_debug,
2263 };
2264
2265
2266 struct sg_proc_leaf {
2267         const char * name;
2268         struct file_operations * fops;
2269 };
2270
2271 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2272         {"allow_dio", &adio_fops},
2273         {"debug", &debug_fops},
2274         {"def_reserved_size", &dressz_fops},
2275         {"device_hdr", &devhdr_fops},
2276         {"devices", &dev_fops},
2277         {"device_strs", &devstrs_fops},
2278         {"version", &version_fops}
2279 };
2280
2281 static int
2282 sg_proc_init(void)
2283 {
2284         int k, mask;
2285         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2286         struct sg_proc_leaf * leaf;
2287
2288         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2289         if (!sg_proc_sgp)
2290                 return 1;
2291         for (k = 0; k < num_leaves; ++k) {
2292                 leaf = &sg_proc_leaf_arr[k];
2293                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2294                 leaf->fops->owner = THIS_MODULE;
2295                 leaf->fops->read = seq_read;
2296                 leaf->fops->llseek = seq_lseek;
2297                 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2298         }
2299         return 0;
2300 }
2301
2302 static void
2303 sg_proc_cleanup(void)
2304 {
2305         int k;
2306         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2307
2308         if (!sg_proc_sgp)
2309                 return;
2310         for (k = 0; k < num_leaves; ++k)
2311                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2312         remove_proc_entry(sg_proc_sg_dirname, NULL);
2313 }
2314
2315
2316 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2317 {
2318         seq_printf(s, "%d\n", *((int *)s->private));
2319         return 0;
2320 }
2321
2322 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2323 {
2324         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2325 }
2326
2327 static ssize_t 
2328 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2329                    size_t count, loff_t *off)
2330 {
2331         int num;
2332         char buff[11];
2333
2334         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2335                 return -EACCES;
2336         num = (count < 10) ? count : 10;
2337         if (copy_from_user(buff, buffer, num))
2338                 return -EFAULT;
2339         buff[num] = '\0';
2340         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2341         return count;
2342 }
2343
2344 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2345 {
2346         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2347 }
2348
2349 static ssize_t 
2350 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2351                      size_t count, loff_t *off)
2352 {
2353         int num;
2354         unsigned long k = ULONG_MAX;
2355         char buff[11];
2356
2357         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2358                 return -EACCES;
2359         num = (count < 10) ? count : 10;
2360         if (copy_from_user(buff, buffer, num))
2361                 return -EFAULT;
2362         buff[num] = '\0';
2363         k = simple_strtoul(buff, NULL, 10);
2364         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2365                 sg_big_buff = k;
2366                 return count;
2367         }
2368         return -ERANGE;
2369 }
2370
2371 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2372 {
2373         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2374                    sg_version_date);
2375         return 0;
2376 }
2377
2378 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2379 {
2380         return single_open(file, sg_proc_seq_show_version, NULL);
2381 }
2382
2383 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2384 {
2385         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2386                    "online\n");
2387         return 0;
2388 }
2389
2390 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2391 {
2392         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2393 }
2394
2395 struct sg_proc_deviter {
2396         loff_t  index;
2397         size_t  max;
2398 };
2399
2400 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2401 {
2402         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2403
2404         s->private = it;
2405         if (! it)
2406                 return NULL;
2407
2408         it->index = *pos;
2409         it->max = sg_last_dev();
2410         if (it->index >= it->max)
2411                 return NULL;
2412         return it;
2413 }
2414
2415 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2416 {
2417         struct sg_proc_deviter * it = s->private;
2418
2419         *pos = ++it->index;
2420         return (it->index < it->max) ? it : NULL;
2421 }
2422
2423 static void dev_seq_stop(struct seq_file *s, void *v)
2424 {
2425         kfree(s->private);
2426 }
2427
2428 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2429 {
2430         return seq_open(file, &dev_seq_ops);
2431 }
2432
2433 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2434 {
2435         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2436         Sg_device *sdp;
2437         struct scsi_device *scsidp;
2438         unsigned long iflags;
2439
2440         read_lock_irqsave(&sg_index_lock, iflags);
2441         sdp = it ? sg_lookup_dev(it->index) : NULL;
2442         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2443                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2444                               scsidp->host->host_no, scsidp->channel,
2445                               scsidp->id, scsidp->lun, (int) scsidp->type,
2446                               1,
2447                               (int) scsidp->queue_depth,
2448                               (int) scsidp->device_busy,
2449                               (int) scsi_device_online(scsidp));
2450         else
2451                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2452         read_unlock_irqrestore(&sg_index_lock, iflags);
2453         return 0;
2454 }
2455
2456 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2457 {
2458         return seq_open(file, &devstrs_seq_ops);
2459 }
2460
2461 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2462 {
2463         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2464         Sg_device *sdp;
2465         struct scsi_device *scsidp;
2466         unsigned long iflags;
2467
2468         read_lock_irqsave(&sg_index_lock, iflags);
2469         sdp = it ? sg_lookup_dev(it->index) : NULL;
2470         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2471                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2472                            scsidp->vendor, scsidp->model, scsidp->rev);
2473         else
2474                 seq_printf(s, "<no active device>\n");
2475         read_unlock_irqrestore(&sg_index_lock, iflags);
2476         return 0;
2477 }
2478
2479 /* must be called while holding sg_index_lock */
2480 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2481 {
2482         int k, m, new_interface, blen, usg;
2483         Sg_request *srp;
2484         Sg_fd *fp;
2485         const sg_io_hdr_t *hp;
2486         const char * cp;
2487         unsigned int ms;
2488
2489         k = 0;
2490         list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2491                 k++;
2492                 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2493                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2494                            "(res)sgat=%d low_dma=%d\n", k,
2495                            jiffies_to_msecs(fp->timeout),
2496                            fp->reserve.bufflen,
2497                            (int) fp->reserve.k_use_sg,
2498                            (int) fp->low_dma);
2499                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2500                            (int) fp->cmd_q, (int) fp->force_packid,
2501                            (int) fp->keep_orphan, (int) fp->closed);
2502                 for (m = 0, srp = fp->headrp;
2503                                 srp != NULL;
2504                                 ++m, srp = srp->nextrp) {
2505                         hp = &srp->header;
2506                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2507                         if (srp->res_used) {
2508                                 if (new_interface && 
2509                                     (SG_FLAG_MMAP_IO & hp->flags))
2510                                         cp = "     mmap>> ";
2511                                 else
2512                                         cp = "     rb>> ";
2513                         } else {
2514                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2515                                         cp = "     dio>> ";
2516                                 else
2517                                         cp = "     ";
2518                         }
2519                         seq_printf(s, cp);
2520                         blen = srp->data.bufflen;
2521                         usg = srp->data.k_use_sg;
2522                         seq_printf(s, srp->done ? 
2523                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2524                                    : "act:");
2525                         seq_printf(s, " id=%d blen=%d",
2526                                    srp->header.pack_id, blen);
2527                         if (srp->done)
2528                                 seq_printf(s, " dur=%d", hp->duration);
2529                         else {
2530                                 ms = jiffies_to_msecs(jiffies);
2531                                 seq_printf(s, " t_o/elap=%d/%d",
2532                                         (new_interface ? hp->timeout :
2533                                                   jiffies_to_msecs(fp->timeout)),
2534                                         (ms > hp->duration ? ms - hp->duration : 0));
2535                         }
2536                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2537                                    (int) srp->data.cmd_opcode);
2538                 }
2539                 if (0 == m)
2540                         seq_printf(s, "     No requests active\n");
2541                 read_unlock(&fp->rq_list_lock);
2542         }
2543 }
2544
2545 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2546 {
2547         return seq_open(file, &debug_seq_ops);
2548 }
2549
2550 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2551 {
2552         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2553         Sg_device *sdp;
2554         unsigned long iflags;
2555
2556         if (it && (0 == it->index)) {
2557                 seq_printf(s, "max_active_device=%d(origin 1)\n",
2558                            (int)it->max);
2559                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2560         }
2561
2562         read_lock_irqsave(&sg_index_lock, iflags);
2563         sdp = it ? sg_lookup_dev(it->index) : NULL;
2564         if (sdp && !list_empty(&sdp->sfds)) {
2565                 struct scsi_device *scsidp = sdp->device;
2566
2567                 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2568                 if (sdp->detached)
2569                         seq_printf(s, "detached pending close ");
2570                 else
2571                         seq_printf
2572                             (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2573                              scsidp->host->host_no,
2574                              scsidp->channel, scsidp->id,
2575                              scsidp->lun,
2576                              scsidp->host->hostt->emulated);
2577                 seq_printf(s, " sg_tablesize=%d excl=%d\n",
2578                            sdp->sg_tablesize, sdp->exclude);
2579                 sg_proc_debug_helper(s, sdp);
2580         }
2581         read_unlock_irqrestore(&sg_index_lock, iflags);
2582         return 0;
2583 }
2584
2585 #endif                          /* CONFIG_SCSI_PROC_FS */
2586
2587 module_init(init_sg);
2588 module_exit(exit_sg);