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