[CIFS] Defer close of file handle slightly if there are pending writes that
[sfrench/cifs-2.6.git] / fs / cifs / cifsfs.c
1 /*
2  *   fs/cifs/cifsfs.c
3  *
4  *   Copyright (C) International Business Machines  Corp., 2002,2004
5  *   Author(s): Steve French (sfrench@us.ibm.com)
6  *
7  *   Common Internet FileSystem (CIFS) client
8  *
9  *   This library is free software; you can redistribute it and/or modify
10  *   it under the terms of the GNU Lesser General Public License as published
11  *   by the Free Software Foundation; either version 2.1 of the License, or
12  *   (at your option) any later version.
13  *
14  *   This library is distributed in the hope that it will be useful,
15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
17  *   the GNU Lesser General Public License for more details.
18  *
19  *   You should have received a copy of the GNU Lesser General Public License
20  *   along with this library; if not, write to the Free Software
21  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22  */
23
24 /* Note that BB means BUGBUG (ie something to fix eventually) */
25
26 #include <linux/module.h>
27 #include <linux/fs.h>
28 #include <linux/mount.h>
29 #include <linux/slab.h>
30 #include <linux/init.h>
31 #include <linux/list.h>
32 #include <linux/seq_file.h>
33 #include <linux/vfs.h>
34 #include <linux/mempool.h>
35 #include "cifsfs.h"
36 #include "cifspdu.h"
37 #define DECLARE_GLOBALS_HERE
38 #include "cifsglob.h"
39 #include "cifsproto.h"
40 #include "cifs_debug.h"
41 #include "cifs_fs_sb.h"
42 #include <linux/mm.h>
43 #define CIFS_MAGIC_NUMBER 0xFF534D42    /* the first four bytes of SMB PDUs */
44
45 #ifdef CONFIG_CIFS_QUOTA
46 static struct quotactl_ops cifs_quotactl_ops;
47 #endif
48
49 int cifsFYI = 0;
50 int cifsERROR = 1;
51 int traceSMB = 0;
52 unsigned int oplockEnabled = 1;
53 unsigned int experimEnabled = 0;
54 unsigned int linuxExtEnabled = 1;
55 unsigned int lookupCacheEnabled = 1;
56 unsigned int multiuser_mount = 0;
57 unsigned int extended_security = 0;
58 unsigned int ntlmv2_support = 0;
59 unsigned int sign_CIFS_PDUs = 1;
60 extern struct task_struct * oplockThread; /* remove sparse warning */
61 struct task_struct * oplockThread = NULL;
62 extern struct task_struct * dnotifyThread; /* remove sparse warning */
63 struct task_struct * dnotifyThread = NULL;
64 unsigned int CIFSMaxBufSize = CIFS_MAX_MSGSIZE;
65 module_param(CIFSMaxBufSize, int, 0);
66 MODULE_PARM_DESC(CIFSMaxBufSize,"Network buffer size (not including header). Default: 16384 Range: 8192 to 130048");
67 unsigned int cifs_min_rcv = CIFS_MIN_RCV_POOL;
68 module_param(cifs_min_rcv, int, 0);
69 MODULE_PARM_DESC(cifs_min_rcv,"Network buffers in pool. Default: 4 Range: 1 to 64");
70 unsigned int cifs_min_small = 30;
71 module_param(cifs_min_small, int, 0);
72 MODULE_PARM_DESC(cifs_min_small,"Small network buffers in pool. Default: 30 Range: 2 to 256");
73 unsigned int cifs_max_pending = CIFS_MAX_REQ;
74 module_param(cifs_max_pending, int, 0);
75 MODULE_PARM_DESC(cifs_max_pending,"Simultaneous requests to server. Default: 50 Range: 2 to 256");
76
77 static DECLARE_COMPLETION(cifs_oplock_exited);
78 static DECLARE_COMPLETION(cifs_dnotify_exited);
79
80 extern mempool_t *cifs_sm_req_poolp;
81 extern mempool_t *cifs_req_poolp;
82 extern mempool_t *cifs_mid_poolp;
83
84 extern kmem_cache_t *cifs_oplock_cachep;
85
86 static int
87 cifs_read_super(struct super_block *sb, void *data,
88                 const char *devname, int silent)
89 {
90         struct inode *inode;
91         struct cifs_sb_info *cifs_sb;
92         int rc = 0;
93
94         sb->s_flags |= MS_NODIRATIME; /* and probably even noatime */
95         sb->s_fs_info = kmalloc(sizeof(struct cifs_sb_info),GFP_KERNEL);
96         cifs_sb = CIFS_SB(sb);
97         if(cifs_sb == NULL)
98                 return -ENOMEM;
99         else
100                 memset(cifs_sb,0,sizeof(struct cifs_sb_info));
101         
102
103         rc = cifs_mount(sb, cifs_sb, data, devname);
104
105         if (rc) {
106                 if (!silent)
107                         cERROR(1,
108                                ("cifs_mount failed w/return code = %d", rc));
109                 goto out_mount_failed;
110         }
111
112         sb->s_magic = CIFS_MAGIC_NUMBER;
113         sb->s_op = &cifs_super_ops;
114 /*      if(cifs_sb->tcon->ses->server->maxBuf > MAX_CIFS_HDR_SIZE + 512)
115             sb->s_blocksize = cifs_sb->tcon->ses->server->maxBuf - MAX_CIFS_HDR_SIZE; */
116 #ifdef CONFIG_CIFS_QUOTA
117         sb->s_qcop = &cifs_quotactl_ops;
118 #endif
119         sb->s_blocksize = CIFS_MAX_MSGSIZE;
120         sb->s_blocksize_bits = 14;      /* default 2**14 = CIFS_MAX_MSGSIZE */
121         inode = iget(sb, ROOT_I);
122
123         if (!inode) {
124                 rc = -ENOMEM;
125                 goto out_no_root;
126         }
127
128         sb->s_root = d_alloc_root(inode);
129
130         if (!sb->s_root) {
131                 rc = -ENOMEM;
132                 goto out_no_root;
133         }
134
135         return 0;
136
137 out_no_root:
138         cERROR(1, ("cifs_read_super: get root inode failed"));
139         if (inode)
140                 iput(inode);
141
142 out_mount_failed:
143         if(cifs_sb) {
144                 if(cifs_sb->local_nls)
145                         unload_nls(cifs_sb->local_nls); 
146                 kfree(cifs_sb);
147         }
148         return rc;
149 }
150
151 static void
152 cifs_put_super(struct super_block *sb)
153 {
154         int rc = 0;
155         struct cifs_sb_info *cifs_sb;
156
157         cFYI(1, ("In cifs_put_super"));
158         cifs_sb = CIFS_SB(sb);
159         if(cifs_sb == NULL) {
160                 cFYI(1,("Empty cifs superblock info passed to unmount"));
161                 return;
162         }
163         rc = cifs_umount(sb, cifs_sb); 
164         if (rc) {
165                 cERROR(1, ("cifs_umount failed with return code %d", rc));
166         }
167         unload_nls(cifs_sb->local_nls);
168         kfree(cifs_sb);
169         return;
170 }
171
172 static int
173 cifs_statfs(struct super_block *sb, struct kstatfs *buf)
174 {
175         int xid; 
176         int rc = -EOPNOTSUPP;
177         struct cifs_sb_info *cifs_sb;
178         struct cifsTconInfo *pTcon;
179
180         xid = GetXid();
181
182         cifs_sb = CIFS_SB(sb);
183         pTcon = cifs_sb->tcon;
184
185         buf->f_type = CIFS_MAGIC_NUMBER;
186
187         /* instead could get the real value via SMB_QUERY_FS_ATTRIBUTE_INFO */
188         buf->f_namelen = PATH_MAX; /* PATH_MAX may be too long - it would 
189                                       presumably be total path, but note
190                                       that some servers (includinng Samba 3)
191                                       have a shorter maximum path */
192         buf->f_files = 0;       /* undefined */
193         buf->f_ffree = 0;       /* unlimited */
194
195 #ifdef CONFIG_CIFS_EXPERIMENTAL
196 /* BB we could add a second check for a QFS Unix capability bit */
197 /* BB FIXME check CIFS_POSIX_EXTENSIONS Unix cap first FIXME BB */
198     if ((pTcon->ses->capabilities & CAP_UNIX) && (CIFS_POSIX_EXTENSIONS &
199                         le64_to_cpu(pTcon->fsUnixInfo.Capability)))
200             rc = CIFSSMBQFSPosixInfo(xid, pTcon, buf);
201
202     /* Only need to call the old QFSInfo if failed
203     on newer one */
204     if(rc)
205 #endif /* CIFS_EXPERIMENTAL */
206         rc = CIFSSMBQFSInfo(xid, pTcon, buf);
207
208         /* Old Windows servers do not support level 103, retry with level 
209            one if old server failed the previous call */ 
210         if(rc)
211                 rc = SMBOldQFSInfo(xid, pTcon, buf);
212         /*     
213            int f_type;
214            __fsid_t f_fsid;
215            int f_namelen;  */
216         /* BB get from info in tcon struct at mount time call to QFSAttrInfo */
217         FreeXid(xid);
218         return 0;               /* always return success? what if volume is no
219                                    longer available? */
220 }
221
222 static int cifs_permission(struct inode * inode, int mask, struct nameidata *nd)
223 {
224         struct cifs_sb_info *cifs_sb;
225
226         cifs_sb = CIFS_SB(inode->i_sb);
227
228         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_PERM) {
229                 return 0;
230         } else /* file mode might have been restricted at mount time 
231                 on the client (above and beyond ACL on servers) for  
232                 servers which do not support setting and viewing mode bits,
233                 so allowing client to check permissions is useful */ 
234                 return generic_permission(inode, mask, NULL);
235 }
236
237 static kmem_cache_t *cifs_inode_cachep;
238 static kmem_cache_t *cifs_req_cachep;
239 static kmem_cache_t *cifs_mid_cachep;
240 kmem_cache_t *cifs_oplock_cachep;
241 static kmem_cache_t *cifs_sm_req_cachep;
242 mempool_t *cifs_sm_req_poolp;
243 mempool_t *cifs_req_poolp;
244 mempool_t *cifs_mid_poolp;
245
246 static struct inode *
247 cifs_alloc_inode(struct super_block *sb)
248 {
249         struct cifsInodeInfo *cifs_inode;
250         cifs_inode = kmem_cache_alloc(cifs_inode_cachep, SLAB_KERNEL);
251         if (!cifs_inode)
252                 return NULL;
253         cifs_inode->cifsAttrs = 0x20;   /* default */
254         atomic_set(&cifs_inode->inUse, 0);
255         cifs_inode->time = 0;
256         /* Until the file is open and we have gotten oplock
257         info back from the server, can not assume caching of
258         file data or metadata */
259         cifs_inode->clientCanCacheRead = FALSE;
260         cifs_inode->clientCanCacheAll = FALSE;
261         cifs_inode->vfs_inode.i_blksize = CIFS_MAX_MSGSIZE;
262         cifs_inode->vfs_inode.i_blkbits = 14;  /* 2**14 = CIFS_MAX_MSGSIZE */
263         cifs_inode->vfs_inode.i_flags = S_NOATIME | S_NOCMTIME;
264         INIT_LIST_HEAD(&cifs_inode->openFileList);
265         return &cifs_inode->vfs_inode;
266 }
267
268 static void
269 cifs_destroy_inode(struct inode *inode)
270 {
271         kmem_cache_free(cifs_inode_cachep, CIFS_I(inode));
272 }
273
274 /*
275  * cifs_show_options() is for displaying mount options in /proc/mounts.
276  * Not all settable options are displayed but most of the important
277  * ones are.
278  */
279 static int
280 cifs_show_options(struct seq_file *s, struct vfsmount *m)
281 {
282         struct cifs_sb_info *cifs_sb;
283
284         cifs_sb = CIFS_SB(m->mnt_sb);
285
286         if (cifs_sb) {
287                 if (cifs_sb->tcon) {
288                         seq_printf(s, ",unc=%s", cifs_sb->tcon->treeName);
289                         if (cifs_sb->tcon->ses) {
290                                 if (cifs_sb->tcon->ses->userName)
291                                         seq_printf(s, ",username=%s",
292                                            cifs_sb->tcon->ses->userName);
293                                 if(cifs_sb->tcon->ses->domainName)
294                                         seq_printf(s, ",domain=%s",
295                                            cifs_sb->tcon->ses->domainName);
296                         }
297                 }
298                 seq_printf(s, ",rsize=%d",cifs_sb->rsize);
299                 seq_printf(s, ",wsize=%d",cifs_sb->wsize);
300         }
301         return 0;
302 }
303
304 #ifdef CONFIG_CIFS_QUOTA
305 int cifs_xquota_set(struct super_block * sb, int quota_type, qid_t qid,
306                 struct fs_disk_quota * pdquota)
307 {
308         int xid;
309         int rc = 0;
310         struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
311         struct cifsTconInfo *pTcon;
312         
313         if(cifs_sb)
314                 pTcon = cifs_sb->tcon;
315         else
316                 return -EIO;
317
318
319         xid = GetXid();
320         if(pTcon) {
321                 cFYI(1,("set type: 0x%x id: %d",quota_type,qid));               
322         } else {
323                 return -EIO;
324         }
325
326         FreeXid(xid);
327         return rc;
328 }
329
330 int cifs_xquota_get(struct super_block * sb, int quota_type, qid_t qid,
331                 struct fs_disk_quota * pdquota)
332 {
333         int xid;
334         int rc = 0;
335         struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
336         struct cifsTconInfo *pTcon;
337
338         if(cifs_sb)
339                 pTcon = cifs_sb->tcon;
340         else
341                 return -EIO;
342
343         xid = GetXid();
344         if(pTcon) {
345                 cFYI(1,("set type: 0x%x id: %d",quota_type,qid));
346         } else {
347                 rc = -EIO;
348         }
349
350         FreeXid(xid);
351         return rc;
352 }
353
354 int cifs_xstate_set(struct super_block * sb, unsigned int flags, int operation)
355 {
356         int xid; 
357         int rc = 0;
358         struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
359         struct cifsTconInfo *pTcon;
360
361         if(cifs_sb)
362                 pTcon = cifs_sb->tcon;
363         else
364                 return -EIO;
365
366         xid = GetXid();
367         if(pTcon) {
368                 cFYI(1,("flags: 0x%x operation: 0x%x",flags,operation));
369         } else {
370                 rc = -EIO;
371         }
372
373         FreeXid(xid);
374         return rc;
375 }
376
377 int cifs_xstate_get(struct super_block * sb, struct fs_quota_stat *qstats)
378 {
379         int xid;
380         int rc = 0;
381         struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
382         struct cifsTconInfo *pTcon;
383
384         if(cifs_sb) {
385                 pTcon = cifs_sb->tcon;
386         } else {
387                 return -EIO;
388         }
389         xid = GetXid();
390         if(pTcon) {
391                 cFYI(1,("pqstats %p",qstats));          
392         } else {
393                 rc = -EIO;
394         }
395
396         FreeXid(xid);
397         return rc;
398 }
399
400 static struct quotactl_ops cifs_quotactl_ops = {
401         .set_xquota     = cifs_xquota_set,
402         .get_xquota     = cifs_xquota_set,
403         .set_xstate     = cifs_xstate_set,
404         .get_xstate     = cifs_xstate_get,
405 };
406 #endif
407
408 static void cifs_umount_begin(struct super_block * sblock)
409 {
410         struct cifs_sb_info *cifs_sb;
411         struct cifsTconInfo * tcon;
412
413         cifs_sb = CIFS_SB(sblock);
414         if(cifs_sb == NULL)
415                 return;
416
417         tcon = cifs_sb->tcon;
418         if(tcon == NULL)
419                 return;
420         down(&tcon->tconSem);
421         if (atomic_read(&tcon->useCount) == 1)
422                 tcon->tidStatus = CifsExiting;
423         up(&tcon->tconSem);
424
425         if(tcon->ses && tcon->ses->server)
426         {
427                 cERROR(1,("wake up tasks now - umount begin not complete"));
428                 wake_up_all(&tcon->ses->server->request_q);
429         }
430 /* BB FIXME - finish add checks for tidStatus BB */
431
432         return;
433 }
434         
435
436 static int cifs_remount(struct super_block *sb, int *flags, char *data)
437 {
438         *flags |= MS_NODIRATIME;
439         return 0;
440 }
441
442 struct super_operations cifs_super_ops = {
443         .read_inode = cifs_read_inode,
444         .put_super = cifs_put_super,
445         .statfs = cifs_statfs,
446         .alloc_inode = cifs_alloc_inode,
447         .destroy_inode = cifs_destroy_inode,
448 /*      .drop_inode         = generic_delete_inode, 
449         .delete_inode   = cifs_delete_inode,  *//* Do not need the above two functions     
450    unless later we add lazy close of inodes or unless the kernel forgets to call
451    us with the same number of releases (closes) as opens */
452         .show_options = cifs_show_options,
453 /*      .umount_begin   = cifs_umount_begin, */ /* BB finish in the future */
454         .remount_fs = cifs_remount,
455 };
456
457 static struct super_block *
458 cifs_get_sb(struct file_system_type *fs_type,
459             int flags, const char *dev_name, void *data)
460 {
461         int rc;
462         struct super_block *sb = sget(fs_type, NULL, set_anon_super, NULL);
463
464         cFYI(1, ("Devname: %s flags: %d ", dev_name, flags));
465
466         if (IS_ERR(sb))
467                 return sb;
468
469         sb->s_flags = flags;
470
471         rc = cifs_read_super(sb, data, dev_name, flags & MS_VERBOSE ? 1 : 0);
472         if (rc) {
473                 up_write(&sb->s_umount);
474                 deactivate_super(sb);
475                 return ERR_PTR(rc);
476         }
477         sb->s_flags |= MS_ACTIVE;
478         return sb;
479 }
480
481 static ssize_t
482 cifs_read_wrapper(struct file * file, char __user *read_data, size_t read_size,
483           loff_t * poffset)
484 {
485         if(file->f_dentry == NULL)
486                 return -EIO;
487         else if(file->f_dentry->d_inode == NULL)
488                 return -EIO;
489
490         cFYI(1,("In read_wrapper size %zd at %lld",read_size,*poffset));
491
492         if(CIFS_I(file->f_dentry->d_inode)->clientCanCacheRead) {
493                 return generic_file_read(file,read_data,read_size,poffset);
494         } else {
495                 /* BB do we need to lock inode from here until after invalidate? */
496 /*              if(file->f_dentry->d_inode->i_mapping) {
497                         filemap_fdatawrite(file->f_dentry->d_inode->i_mapping);
498                         filemap_fdatawait(file->f_dentry->d_inode->i_mapping);
499                 }*/
500 /*              cifs_revalidate(file->f_dentry);*/ /* BB fixme */
501
502                 /* BB we should make timer configurable - perhaps 
503                    by simply calling cifs_revalidate here */
504                 /* invalidate_remote_inode(file->f_dentry->d_inode);*/
505                 return generic_file_read(file,read_data,read_size,poffset);
506         }
507 }
508
509 static ssize_t
510 cifs_write_wrapper(struct file * file, const char __user *write_data,
511            size_t write_size, loff_t * poffset) 
512 {
513         ssize_t written;
514
515         if(file->f_dentry == NULL)
516                 return -EIO;
517         else if(file->f_dentry->d_inode == NULL)
518                 return -EIO;
519
520         cFYI(1,("In write_wrapper size %zd at %lld",write_size,*poffset));
521
522         written = generic_file_write(file,write_data,write_size,poffset);
523         if(!CIFS_I(file->f_dentry->d_inode)->clientCanCacheAll)  {
524                 if(file->f_dentry->d_inode->i_mapping) {
525                         filemap_fdatawrite(file->f_dentry->d_inode->i_mapping);
526                 }
527         }
528         return written;
529 }
530
531
532 static struct file_system_type cifs_fs_type = {
533         .owner = THIS_MODULE,
534         .name = "cifs",
535         .get_sb = cifs_get_sb,
536         .kill_sb = kill_anon_super,
537         /*  .fs_flags */
538 };
539 struct inode_operations cifs_dir_inode_ops = {
540         .create = cifs_create,
541         .lookup = cifs_lookup,
542         .getattr = cifs_getattr,
543         .unlink = cifs_unlink,
544         .link = cifs_hardlink,
545         .mkdir = cifs_mkdir,
546         .rmdir = cifs_rmdir,
547         .rename = cifs_rename,
548         .permission = cifs_permission,
549 /*      revalidate:cifs_revalidate,   */
550         .setattr = cifs_setattr,
551         .symlink = cifs_symlink,
552         .mknod   = cifs_mknod,
553 #ifdef CONFIG_CIFS_XATTR
554         .setxattr = cifs_setxattr,
555         .getxattr = cifs_getxattr,
556         .listxattr = cifs_listxattr,
557         .removexattr = cifs_removexattr,
558 #endif
559 };
560
561 struct inode_operations cifs_file_inode_ops = {
562 /*      revalidate:cifs_revalidate, */
563         .setattr = cifs_setattr,
564         .getattr = cifs_getattr, /* do we need this anymore? */
565         .rename = cifs_rename,
566         .permission = cifs_permission,
567 #ifdef CONFIG_CIFS_XATTR
568         .setxattr = cifs_setxattr,
569         .getxattr = cifs_getxattr,
570         .listxattr = cifs_listxattr,
571         .removexattr = cifs_removexattr,
572 #endif 
573 };
574
575 struct inode_operations cifs_symlink_inode_ops = {
576         .readlink = generic_readlink, 
577         .follow_link = cifs_follow_link,
578         .put_link = cifs_put_link,
579         .permission = cifs_permission,
580         /* BB add the following two eventually */
581         /* revalidate: cifs_revalidate,
582            setattr:    cifs_notify_change, *//* BB do we need notify change */
583 #ifdef CONFIG_CIFS_XATTR
584         .setxattr = cifs_setxattr,
585         .getxattr = cifs_getxattr,
586         .listxattr = cifs_listxattr,
587         .removexattr = cifs_removexattr,
588 #endif 
589 };
590
591 struct file_operations cifs_file_ops = {
592         .read = cifs_read_wrapper,
593         .write = cifs_write_wrapper, 
594         .open = cifs_open,
595         .release = cifs_close,
596         .lock = cifs_lock,
597         .fsync = cifs_fsync,
598         .flush = cifs_flush,
599         .mmap  = cifs_file_mmap,
600         .sendfile = generic_file_sendfile,
601 #ifdef CONFIG_CIFS_POSIX
602         .ioctl  = cifs_ioctl,
603 #endif /* CONFIG_CIFS_POSIX */
604
605 #ifdef CONFIG_CIFS_EXPERIMENTAL
606         .readv = generic_file_readv,
607         .writev = generic_file_writev,
608         .aio_read = generic_file_aio_read,
609         .aio_write = generic_file_aio_write,
610         .dir_notify = cifs_dir_notify,
611 #endif /* CONFIG_CIFS_EXPERIMENTAL */
612 };
613
614 struct file_operations cifs_file_direct_ops = {
615         /* no mmap, no aio, no readv - 
616            BB reevaluate whether they can be done with directio, no cache */
617         .read = cifs_user_read,
618         .write = cifs_user_write,
619         .open = cifs_open,
620         .release = cifs_close,
621         .lock = cifs_lock,
622         .fsync = cifs_fsync,
623         .flush = cifs_flush,
624         .sendfile = generic_file_sendfile, /* BB removeme BB */
625 #ifdef CONFIG_CIFS_POSIX
626         .ioctl  = cifs_ioctl,
627 #endif /* CONFIG_CIFS_POSIX */
628
629 #ifdef CONFIG_CIFS_EXPERIMENTAL
630         .dir_notify = cifs_dir_notify,
631 #endif /* CONFIG_CIFS_EXPERIMENTAL */
632 };
633
634 struct file_operations cifs_dir_ops = {
635         .readdir = cifs_readdir,
636         .release = cifs_closedir,
637         .read    = generic_read_dir,
638 #ifdef CONFIG_CIFS_EXPERIMENTAL
639         .dir_notify = cifs_dir_notify,
640 #endif /* CONFIG_CIFS_EXPERIMENTAL */
641         .ioctl  = cifs_ioctl,
642 };
643
644 static void
645 cifs_init_once(void *inode, kmem_cache_t * cachep, unsigned long flags)
646 {
647         struct cifsInodeInfo *cifsi = inode;
648
649         if ((flags & (SLAB_CTOR_VERIFY | SLAB_CTOR_CONSTRUCTOR)) ==
650             SLAB_CTOR_CONSTRUCTOR) {
651                 inode_init_once(&cifsi->vfs_inode);
652                 INIT_LIST_HEAD(&cifsi->lockList);
653         }
654 }
655
656 static int
657 cifs_init_inodecache(void)
658 {
659         cifs_inode_cachep = kmem_cache_create("cifs_inode_cache",
660                                               sizeof (struct cifsInodeInfo),
661                                               0, SLAB_RECLAIM_ACCOUNT,
662                                               cifs_init_once, NULL);
663         if (cifs_inode_cachep == NULL)
664                 return -ENOMEM;
665
666         return 0;
667 }
668
669 static void
670 cifs_destroy_inodecache(void)
671 {
672         if (kmem_cache_destroy(cifs_inode_cachep))
673                 printk(KERN_WARNING "cifs_inode_cache: error freeing\n");
674 }
675
676 static int
677 cifs_init_request_bufs(void)
678 {
679         if(CIFSMaxBufSize < 8192) {
680         /* Buffer size can not be smaller than 2 * PATH_MAX since maximum
681         Unicode path name has to fit in any SMB/CIFS path based frames */
682                 CIFSMaxBufSize = 8192;
683         } else if (CIFSMaxBufSize > 1024*127) {
684                 CIFSMaxBufSize = 1024 * 127;
685         } else {
686                 CIFSMaxBufSize &= 0x1FE00; /* Round size to even 512 byte mult*/
687         }
688 /*      cERROR(1,("CIFSMaxBufSize %d 0x%x",CIFSMaxBufSize,CIFSMaxBufSize)); */
689         cifs_req_cachep = kmem_cache_create("cifs_request",
690                                             CIFSMaxBufSize +
691                                             MAX_CIFS_HDR_SIZE, 0,
692                                             SLAB_HWCACHE_ALIGN, NULL, NULL);
693         if (cifs_req_cachep == NULL)
694                 return -ENOMEM;
695
696         if(cifs_min_rcv < 1)
697                 cifs_min_rcv = 1;
698         else if (cifs_min_rcv > 64) {
699                 cifs_min_rcv = 64;
700                 cERROR(1,("cifs_min_rcv set to maximum (64)"));
701         }
702
703         cifs_req_poolp = mempool_create(cifs_min_rcv,
704                                         mempool_alloc_slab,
705                                         mempool_free_slab,
706                                         cifs_req_cachep);
707
708         if(cifs_req_poolp == NULL) {
709                 kmem_cache_destroy(cifs_req_cachep);
710                 return -ENOMEM;
711         }
712         /* 256 (MAX_CIFS_HDR_SIZE bytes is enough for most SMB responses and
713         almost all handle based requests (but not write response, nor is it
714         sufficient for path based requests).  A smaller size would have
715         been more efficient (compacting multiple slab items on one 4k page) 
716         for the case in which debug was on, but this larger size allows
717         more SMBs to use small buffer alloc and is still much more
718         efficient to alloc 1 per page off the slab compared to 17K (5page) 
719         alloc of large cifs buffers even when page debugging is on */
720         cifs_sm_req_cachep = kmem_cache_create("cifs_small_rq",
721                         MAX_CIFS_HDR_SIZE, 0, SLAB_HWCACHE_ALIGN, NULL, NULL);
722         if (cifs_sm_req_cachep == NULL) {
723                 mempool_destroy(cifs_req_poolp);
724                 kmem_cache_destroy(cifs_req_cachep);
725                 return -ENOMEM;              
726         }
727
728         if(cifs_min_small < 2)
729                 cifs_min_small = 2;
730         else if (cifs_min_small > 256) {
731                 cifs_min_small = 256;
732                 cFYI(1,("cifs_min_small set to maximum (256)"));
733         }
734
735         cifs_sm_req_poolp = mempool_create(cifs_min_small,
736                                 mempool_alloc_slab,
737                                 mempool_free_slab,
738                                 cifs_sm_req_cachep);
739
740         if(cifs_sm_req_poolp == NULL) {
741                 mempool_destroy(cifs_req_poolp);
742                 kmem_cache_destroy(cifs_req_cachep);
743                 kmem_cache_destroy(cifs_sm_req_cachep);
744                 return -ENOMEM;
745         }
746
747         return 0;
748 }
749
750 static void
751 cifs_destroy_request_bufs(void)
752 {
753         mempool_destroy(cifs_req_poolp);
754         if (kmem_cache_destroy(cifs_req_cachep))
755                 printk(KERN_WARNING
756                        "cifs_destroy_request_cache: error not all structures were freed\n");
757         mempool_destroy(cifs_sm_req_poolp);
758         if (kmem_cache_destroy(cifs_sm_req_cachep))
759                 printk(KERN_WARNING
760                       "cifs_destroy_request_cache: cifs_small_rq free error\n");
761 }
762
763 static int
764 cifs_init_mids(void)
765 {
766         cifs_mid_cachep = kmem_cache_create("cifs_mpx_ids",
767                                 sizeof (struct mid_q_entry), 0,
768                                 SLAB_HWCACHE_ALIGN, NULL, NULL);
769         if (cifs_mid_cachep == NULL)
770                 return -ENOMEM;
771
772         cifs_mid_poolp = mempool_create(3 /* a reasonable min simultan opers */,
773                                         mempool_alloc_slab,
774                                         mempool_free_slab,
775                                         cifs_mid_cachep);
776         if(cifs_mid_poolp == NULL) {
777                 kmem_cache_destroy(cifs_mid_cachep);
778                 return -ENOMEM;
779         }
780
781         cifs_oplock_cachep = kmem_cache_create("cifs_oplock_structs",
782                                 sizeof (struct oplock_q_entry), 0,
783                                 SLAB_HWCACHE_ALIGN, NULL, NULL);
784         if (cifs_oplock_cachep == NULL) {
785                 kmem_cache_destroy(cifs_mid_cachep);
786                 mempool_destroy(cifs_mid_poolp);
787                 return -ENOMEM;
788         }
789
790         return 0;
791 }
792
793 static void
794 cifs_destroy_mids(void)
795 {
796         mempool_destroy(cifs_mid_poolp);
797         if (kmem_cache_destroy(cifs_mid_cachep))
798                 printk(KERN_WARNING
799                        "cifs_destroy_mids: error not all structures were freed\n");
800
801         if (kmem_cache_destroy(cifs_oplock_cachep))
802                 printk(KERN_WARNING
803                        "error not all oplock structures were freed\n");
804 }
805
806 static int cifs_oplock_thread(void * dummyarg)
807 {
808         struct oplock_q_entry * oplock_item;
809         struct cifsTconInfo *pTcon;
810         struct inode * inode;
811         __u16  netfid;
812         int rc;
813
814         daemonize("cifsoplockd");
815         allow_signal(SIGTERM);
816
817         oplockThread = current;
818         do {
819                 if(try_to_freeze()) 
820                         continue;
821                 
822                 spin_lock(&GlobalMid_Lock);
823                 if(list_empty(&GlobalOplock_Q)) {
824                         spin_unlock(&GlobalMid_Lock);
825                         set_current_state(TASK_INTERRUPTIBLE);
826                         schedule_timeout(39*HZ);
827                 } else {
828                         oplock_item = list_entry(GlobalOplock_Q.next, 
829                                 struct oplock_q_entry, qhead);
830                         if(oplock_item) {
831                                 cFYI(1,("found oplock item to write out")); 
832                                 pTcon = oplock_item->tcon;
833                                 inode = oplock_item->pinode;
834                                 netfid = oplock_item->netfid;
835                                 spin_unlock(&GlobalMid_Lock);
836                                 DeleteOplockQEntry(oplock_item);
837                                 /* can not grab inode sem here since it would
838                                 deadlock when oplock received on delete 
839                                 since vfs_unlink holds the i_sem across
840                                 the call */
841                                 /* down(&inode->i_sem);*/
842                                 if (S_ISREG(inode->i_mode)) {
843                                         rc = filemap_fdatawrite(inode->i_mapping);
844                                         if(CIFS_I(inode)->clientCanCacheRead == 0) {
845                                                 filemap_fdatawait(inode->i_mapping);
846                                                 invalidate_remote_inode(inode);
847                                         }
848                                 } else
849                                         rc = 0;
850                                 /* up(&inode->i_sem);*/
851                                 if (rc)
852                                         CIFS_I(inode)->write_behind_rc = rc;
853                                 cFYI(1,("Oplock flush inode %p rc %d",inode,rc));
854
855                                 /* releasing a stale oplock after recent reconnection 
856                                 of smb session using a now incorrect file 
857                                 handle is not a data integrity issue but do  
858                                 not bother sending an oplock release if session 
859                                 to server still is disconnected since oplock 
860                                 already released by the server in that case */
861                                 if(pTcon->tidStatus != CifsNeedReconnect) {
862                                     rc = CIFSSMBLock(0, pTcon, netfid,
863                                             0 /* len */ , 0 /* offset */, 0, 
864                                             0, LOCKING_ANDX_OPLOCK_RELEASE,
865                                             0 /* wait flag */);
866                                         cFYI(1,("Oplock release rc = %d ",rc));
867                                 }
868                         } else
869                                 spin_unlock(&GlobalMid_Lock);
870                         set_current_state(TASK_INTERRUPTIBLE);
871                         schedule_timeout(1);  /* yield in case q were corrupt */
872                 }
873         } while(!signal_pending(current));
874         oplockThread = NULL;
875         complete_and_exit (&cifs_oplock_exited, 0);
876 }
877
878 static int cifs_dnotify_thread(void * dummyarg)
879 {
880         daemonize("cifsdnotifyd");
881         allow_signal(SIGTERM);
882
883         dnotifyThread = current;
884         do {
885                 if(try_to_freeze())
886                         continue;
887                 set_current_state(TASK_INTERRUPTIBLE);
888                 schedule_timeout(39*HZ);
889         } while(!signal_pending(current));
890         complete_and_exit (&cifs_dnotify_exited, 0);
891 }
892
893 static int __init
894 init_cifs(void)
895 {
896         int rc = 0;
897 #ifdef CONFIG_PROC_FS
898         cifs_proc_init();
899 #endif
900         INIT_LIST_HEAD(&GlobalServerList);      /* BB not implemented yet */
901         INIT_LIST_HEAD(&GlobalSMBSessionList);
902         INIT_LIST_HEAD(&GlobalTreeConnectionList);
903         INIT_LIST_HEAD(&GlobalOplock_Q);
904 #ifdef CONFIG_CIFS_EXPERIMENTAL
905         INIT_LIST_HEAD(&GlobalDnotifyReqList);
906         INIT_LIST_HEAD(&GlobalDnotifyRsp_Q);
907 #endif  
908 /*
909  *  Initialize Global counters
910  */
911         atomic_set(&sesInfoAllocCount, 0);
912         atomic_set(&tconInfoAllocCount, 0);
913         atomic_set(&tcpSesAllocCount,0);
914         atomic_set(&tcpSesReconnectCount, 0);
915         atomic_set(&tconInfoReconnectCount, 0);
916
917         atomic_set(&bufAllocCount, 0);
918         atomic_set(&midCount, 0);
919         GlobalCurrentXid = 0;
920         GlobalTotalActiveXid = 0;
921         GlobalMaxActiveXid = 0;
922         rwlock_init(&GlobalSMBSeslock);
923         spin_lock_init(&GlobalMid_Lock);
924
925         if(cifs_max_pending < 2) {
926                 cifs_max_pending = 2;
927                 cFYI(1,("cifs_max_pending set to min of 2"));
928         } else if(cifs_max_pending > 256) {
929                 cifs_max_pending = 256;
930                 cFYI(1,("cifs_max_pending set to max of 256"));
931         }
932
933         rc = cifs_init_inodecache();
934         if (!rc) {
935                 rc = cifs_init_mids();
936                 if (!rc) {
937                         rc = cifs_init_request_bufs();
938                         if (!rc) {
939                                 rc = register_filesystem(&cifs_fs_type);
940                                 if (!rc) {                
941                                         rc = (int)kernel_thread(cifs_oplock_thread, NULL, 
942                                                 CLONE_FS | CLONE_FILES | CLONE_VM);
943                                         if(rc > 0) {
944                                                 rc = (int)kernel_thread(cifs_dnotify_thread, NULL,
945                                                         CLONE_FS | CLONE_FILES | CLONE_VM);
946                                                 if(rc > 0)
947                                                         return 0;
948                                                 else
949                                                         cERROR(1,("error %d create dnotify thread", rc));
950                                         } else {
951                                                 cERROR(1,("error %d create oplock thread",rc));
952                                         }
953                                 }
954                                 cifs_destroy_request_bufs();
955                         }
956                         cifs_destroy_mids();
957                 }
958                 cifs_destroy_inodecache();
959         }
960 #ifdef CONFIG_PROC_FS
961         cifs_proc_clean();
962 #endif
963         return rc;
964 }
965
966 static void __exit
967 exit_cifs(void)
968 {
969         cFYI(0, ("In unregister ie exit_cifs"));
970 #ifdef CONFIG_PROC_FS
971         cifs_proc_clean();
972 #endif
973         unregister_filesystem(&cifs_fs_type);
974         cifs_destroy_inodecache();
975         cifs_destroy_mids();
976         cifs_destroy_request_bufs();
977         if(oplockThread) {
978                 send_sig(SIGTERM, oplockThread, 1);
979                 wait_for_completion(&cifs_oplock_exited);
980         }
981         if(dnotifyThread) {
982                 send_sig(SIGTERM, dnotifyThread, 1);
983                 wait_for_completion(&cifs_dnotify_exited);
984         }
985 }
986
987 MODULE_AUTHOR("Steve French <sfrench@us.ibm.com>");
988 MODULE_LICENSE("GPL");          /* combination of LGPL + GPL source behaves as GPL */
989 MODULE_DESCRIPTION
990     ("VFS to access servers complying with the SNIA CIFS Specification e.g. Samba and Windows");
991 MODULE_VERSION(CIFS_VERSION);
992 module_init(init_cifs)
993 module_exit(exit_cifs)